+20000401
+ - Big OpenBSD CVS update (mainly beginnings of SSH2 infrastructure)
+ - [auth.c session.c sshd.c auth.h]
+ split sshd.c -> auth.c session.c sshd.c plus cleanup and goto-removal
+ - [bufaux.c bufaux.h]
+ support ssh2 bignums
+ - [channels.c channels.h clientloop.c sshd.c nchan.c nchan.h packet.c]
+ [readconf.c ssh.c ssh.h serverloop.c]
+ replace big switch() with function tables (prepare for ssh2)
+ - [ssh2.h]
+ ssh2 message type codes
+ - [sshd.8]
+ reorder Xr to avoid cutting
+ - [serverloop.c]
+ close(fdin) if fdin != fdout, shutdown otherwise, ok theo@
+ - [channels.c]
+ missing close
+ allow bigger packets
+ - [cipher.c cipher.h]
+ support ssh2 ciphers
+ - [compress.c]
+ cleanup, less code
+ - [dispatch.c dispatch.h]
+ function tables for different message types
+ - [log-server.c]
+ do not log() if debuggin to stderr
+ rename a cpp symbol, to avoid param.h collision
+ - [mpaux.c]
+ KNF
+ - [nchan.c]
+ sync w/ channels.c
+
20000326
- Better tests for OpenSSL w/ RSAref
- Added replacement setenv() function from OpenBSD libc. Suggested by
TARGETS=ssh sshd ssh-add ssh-keygen ssh-agent scp $(EXTRA_TARGETS)
-LIBOBJS= atomicio.o authfd.o authfile.o bsd-bindresvport.o bsd-daemon.o bsd-misc.o bsd-mktemp.o bsd-rresvport.o bsd-setenv.o bsd-snprintf.o bsd-strlcat.o bsd-strlcpy.o bufaux.o buffer.o canohost.o channels.o cipher.o compat.o compress.o crc32.o deattack.o fake-getaddrinfo.o fake-getnameinfo.o fingerprint.o hostfile.o key.o log.o match.o mpaux.o nchan.o packet.o radix.o random.o readpass.o rsa.o tildexpand.o ttymodes.o uidswap.o xmalloc.o
+LIBOBJS= atomicio.o authfd.o authfile.o bsd-bindresvport.o bsd-daemon.o bsd-misc.o bsd-mktemp.o bsd-rresvport.o bsd-setenv.o bsd-snprintf.o bsd-strlcat.o bsd-strlcpy.o bufaux.o buffer.o canohost.o channels.o cipher.o compat.o compress.o crc32.o deattack.o dispatch.o fake-getaddrinfo.o fake-getnameinfo.o fingerprint.o hostfile.o key.o log.o match.o mpaux.o nchan.o packet.o radix.o random.o readpass.o rsa.o tildexpand.o ttymodes.o uidswap.o xmalloc.o
SSHOBJS= ssh.o sshconnect.o log-client.o readconf.o clientloop.o
-SSHDOBJS= sshd.o auth-rhosts.o auth-krb4.o auth-pam.o auth-passwd.o auth-rsa.o auth-rh-rsa.o pty.o log-server.o login.o servconf.o serverloop.o bsd-login.o md5crypt.o
+SSHDOBJS= sshd.o auth-rhosts.o auth-krb4.o auth-pam.o auth-passwd.o auth-rsa.o auth-rh-rsa.o pty.o log-server.o login.o servconf.o serverloop.o bsd-login.o md5crypt.o session.o auth.o
TROFFMAN = scp.1 ssh-add.1 ssh-agent.1 ssh-keygen.1 ssh.1 sshd.8
CATMAN = scp.0 ssh-add.0 ssh-agent.0 ssh-keygen.0 ssh.0 sshd.0
--- /dev/null
+/*
+ * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
+ * All rights reserved
+ */
+
+#include "includes.h"
+RCSID("$OpenBSD: auth.c,v 1.1 2000/03/28 21:15:45 markus Exp $");
+
+#include "xmalloc.h"
+#include "rsa.h"
+#include "ssh.h"
+#include "pty.h"
+#include "packet.h"
+#include "buffer.h"
+#include "cipher.h"
+#include "mpaux.h"
+#include "servconf.h"
+#include "channels.h"
+#include "match.h"
+
+#include "session.h"
+#include "dispatch.h"
+
+/* import */
+extern ServerOptions options;
+extern char *forced_command;
+
+/*
+ * Check if the user is allowed to log in via ssh. If user is listed in
+ * DenyUsers or user's primary group is listed in DenyGroups, false will
+ * be returned. If AllowUsers isn't empty and user isn't listed there, or
+ * if AllowGroups isn't empty and user isn't listed there, false will be
+ * returned.
+ * If the user's shell is not executable, false will be returned.
+ * Otherwise true is returned.
+ */
+static int
+allowed_user(struct passwd * pw)
+{
+ struct stat st;
+ struct group *grp;
+ int i;
+#ifdef WITH_AIXAUTHENTICATE
+ char *loginmsg;
+#endif /* WITH_AIXAUTHENTICATE */
+
+ /* Shouldn't be called if pw is NULL, but better safe than sorry... */
+ if (!pw)
+ return 0;
+
+ /* deny if shell does not exists or is not executable */
+ if (stat(pw->pw_shell, &st) != 0)
+ return 0;
+ if (!((st.st_mode & S_IFREG) && (st.st_mode & (S_IXOTH|S_IXUSR|S_IXGRP))))
+ return 0;
+
+ /* Return false if user is listed in DenyUsers */
+ if (options.num_deny_users > 0) {
+ if (!pw->pw_name)
+ return 0;
+ for (i = 0; i < options.num_deny_users; i++)
+ if (match_pattern(pw->pw_name, options.deny_users[i]))
+ return 0;
+ }
+ /* Return false if AllowUsers isn't empty and user isn't listed there */
+ if (options.num_allow_users > 0) {
+ if (!pw->pw_name)
+ return 0;
+ for (i = 0; i < options.num_allow_users; i++)
+ if (match_pattern(pw->pw_name, options.allow_users[i]))
+ break;
+ /* i < options.num_allow_users iff we break for loop */
+ if (i >= options.num_allow_users)
+ return 0;
+ }
+ /* Get the primary group name if we need it. Return false if it fails */
+ if (options.num_deny_groups > 0 || options.num_allow_groups > 0) {
+ grp = getgrgid(pw->pw_gid);
+ if (!grp)
+ return 0;
+
+ /* Return false if user's group is listed in DenyGroups */
+ if (options.num_deny_groups > 0) {
+ if (!grp->gr_name)
+ return 0;
+ for (i = 0; i < options.num_deny_groups; i++)
+ if (match_pattern(grp->gr_name, options.deny_groups[i]))
+ return 0;
+ }
+ /*
+ * Return false if AllowGroups isn't empty and user's group
+ * isn't listed there
+ */
+ if (options.num_allow_groups > 0) {
+ if (!grp->gr_name)
+ return 0;
+ for (i = 0; i < options.num_allow_groups; i++)
+ if (match_pattern(grp->gr_name, options.allow_groups[i]))
+ break;
+ /* i < options.num_allow_groups iff we break for
+ loop */
+ if (i >= options.num_allow_groups)
+ return 0;
+ }
+ }
+
+#ifdef WITH_AIXAUTHENTICATE
+ if (loginrestrictions(pw->pw_name,S_LOGIN,NULL,&loginmsg) != 0)
+ return 0;
+#endif /* WITH_AIXAUTHENTICATE */
+
+ /* We found no reason not to let this user try to log on... */
+ return 1;
+}
+
+/*
+ * convert ssh auth msg type into description
+ */
+char *
+get_authname(int type)
+{
+ static char buf[1024];
+ switch (type) {
+ case SSH_CMSG_AUTH_PASSWORD:
+ return "password";
+ case SSH_CMSG_AUTH_RSA:
+ return "rsa";
+ case SSH_CMSG_AUTH_RHOSTS_RSA:
+ return "rhosts-rsa";
+ case SSH_CMSG_AUTH_RHOSTS:
+ return "rhosts";
+#ifdef KRB4
+ case SSH_CMSG_AUTH_KERBEROS:
+ return "kerberos";
+#endif
+#ifdef SKEY
+ case SSH_CMSG_AUTH_TIS_RESPONSE:
+ return "s/key";
+#endif
+ }
+ snprintf(buf, sizeof buf, "bad-auth-msg-%d", type);
+ return buf;
+}
+
+#define AUTH_FAIL_MAX 6
+#define AUTH_FAIL_LOG (AUTH_FAIL_MAX/2)
+#define AUTH_FAIL_MSG "Too many authentication failures for %.100s"
+
+/*
+ * The user does not exist or access is denied,
+ * but fake indication that authentication is needed.
+ */
+void
+do_fake_authloop1(char *user)
+{
+ int attempt = 0;
+
+ log("Faking authloop for illegal user %.200s from %.200s port %d",
+ user,
+ get_remote_ipaddr(),
+ get_remote_port());
+
+#ifdef WITH_AIXAUTHENTICATE
+ if (strncmp(get_authname(type),"password",
+ strlen(get_authname(type))) == 0)
+ loginfailed(pw->pw_name,get_canonical_hostname(),"ssh");
+#endif /* WITH_AIXAUTHENTICATE */
+
+ /* Indicate that authentication is needed. */
+ packet_start(SSH_SMSG_FAILURE);
+ packet_send();
+ packet_write_wait();
+
+ /*
+ * Keep reading packets, and always respond with a failure. This is
+ * to avoid disclosing whether such a user really exists.
+ */
+ for (attempt = 1;; attempt++) {
+ /* Read a packet. This will not return if the client disconnects. */
+ int plen;
+#ifndef SKEY
+ (void)packet_read(&plen);
+#else /* SKEY */
+ int type = packet_read(&plen);
+ unsigned int dlen;
+ char *password, *skeyinfo;
+ /* Try to send a fake s/key challenge. */
+ if (options.skey_authentication == 1 &&
+ (skeyinfo = skey_fake_keyinfo(user)) != NULL) {
+ password = NULL;
+ if (type == SSH_CMSG_AUTH_TIS) {
+ packet_start(SSH_SMSG_AUTH_TIS_CHALLENGE);
+ packet_put_string(skeyinfo, strlen(skeyinfo));
+ packet_send();
+ packet_write_wait();
+ continue;
+ } else if (type == SSH_CMSG_AUTH_PASSWORD &&
+ options.password_authentication &&
+ (password = packet_get_string(&dlen)) != NULL &&
+ dlen == 5 &&
+ strncasecmp(password, "s/key", 5) == 0 ) {
+ packet_send_debug(skeyinfo);
+ }
+ if (password != NULL)
+ xfree(password);
+ }
+#endif
+ if (attempt > AUTH_FAIL_MAX)
+ packet_disconnect(AUTH_FAIL_MSG, user);
+
+ /*
+ * Send failure. This should be indistinguishable from a
+ * failed authentication.
+ */
+ packet_start(SSH_SMSG_FAILURE);
+ packet_send();
+ packet_write_wait();
+ }
+ /* NOTREACHED */
+ abort();
+}
+
+/*
+ * read packets and try to authenticate local user *pw.
+ * return if authentication is successfull
+ */
+void
+do_authloop(struct passwd * pw)
+{
+ int attempt = 0;
+ unsigned int bits;
+ RSA *client_host_key;
+ BIGNUM *n;
+ char *client_user = NULL, *password = NULL;
+ char user[1024];
+ unsigned int dlen;
+ int plen, nlen, elen;
+ unsigned int ulen;
+ int type = 0;
+ void (*authlog) (const char *fmt,...) = verbose;
+
+ /* Indicate that authentication is needed. */
+ packet_start(SSH_SMSG_FAILURE);
+ packet_send();
+ packet_write_wait();
+
+ for (attempt = 1;; attempt++) {
+ int authenticated = 0;
+ strlcpy(user, "", sizeof user);
+
+ /* Get a packet from the client. */
+ type = packet_read(&plen);
+
+ /* Process the packet. */
+ switch (type) {
+#ifdef AFS
+ case SSH_CMSG_HAVE_KERBEROS_TGT:
+ if (!options.kerberos_tgt_passing) {
+ /* packet_get_all(); */
+ verbose("Kerberos tgt passing disabled.");
+ break;
+ } else {
+ /* Accept Kerberos tgt. */
+ char *tgt = packet_get_string(&dlen);
+ packet_integrity_check(plen, 4 + dlen, type);
+ if (!auth_kerberos_tgt(pw, tgt))
+ verbose("Kerberos tgt REFUSED for %s", pw->pw_name);
+ xfree(tgt);
+ }
+ continue;
+
+ case SSH_CMSG_HAVE_AFS_TOKEN:
+ if (!options.afs_token_passing || !k_hasafs()) {
+ /* packet_get_all(); */
+ verbose("AFS token passing disabled.");
+ break;
+ } else {
+ /* Accept AFS token. */
+ char *token_string = packet_get_string(&dlen);
+ packet_integrity_check(plen, 4 + dlen, type);
+ if (!auth_afs_token(pw, token_string))
+ verbose("AFS token REFUSED for %s", pw->pw_name);
+ xfree(token_string);
+ }
+ continue;
+#endif /* AFS */
+#ifdef KRB4
+ case SSH_CMSG_AUTH_KERBEROS:
+ if (!options.kerberos_authentication) {
+ /* packet_get_all(); */
+ verbose("Kerberos authentication disabled.");
+ break;
+ } else {
+ /* Try Kerberos v4 authentication. */
+ KTEXT_ST auth;
+ char *tkt_user = NULL;
+ char *kdata = packet_get_string((unsigned int *) &auth.length);
+ packet_integrity_check(plen, 4 + auth.length, type);
+
+ if (auth.length < MAX_KTXT_LEN)
+ memcpy(auth.dat, kdata, auth.length);
+ xfree(kdata);
+
+ authenticated = auth_krb4(pw->pw_name, &auth, &tkt_user);
+
+ if (authenticated) {
+ snprintf(user, sizeof user, " tktuser %s", tkt_user);
+ xfree(tkt_user);
+ }
+ }
+ break;
+#endif /* KRB4 */
+
+ case SSH_CMSG_AUTH_RHOSTS:
+ if (!options.rhosts_authentication) {
+ verbose("Rhosts authentication disabled.");
+ break;
+ }
+ /*
+ * Get client user name. Note that we just have to
+ * trust the client; this is one reason why rhosts
+ * authentication is insecure. (Another is
+ * IP-spoofing on a local network.)
+ */
+ client_user = packet_get_string(&ulen);
+ packet_integrity_check(plen, 4 + ulen, type);
+
+ /* Try to authenticate using /etc/hosts.equiv and
+ .rhosts. */
+ authenticated = auth_rhosts(pw, client_user);
+
+ snprintf(user, sizeof user, " ruser %s", client_user);
+ break;
+
+ case SSH_CMSG_AUTH_RHOSTS_RSA:
+ if (!options.rhosts_rsa_authentication) {
+ verbose("Rhosts with RSA authentication disabled.");
+ break;
+ }
+ /*
+ * Get client user name. Note that we just have to
+ * trust the client; root on the client machine can
+ * claim to be any user.
+ */
+ client_user = packet_get_string(&ulen);
+
+ /* Get the client host key. */
+ client_host_key = RSA_new();
+ if (client_host_key == NULL)
+ fatal("RSA_new failed");
+ client_host_key->e = BN_new();
+ client_host_key->n = BN_new();
+ if (client_host_key->e == NULL || client_host_key->n == NULL)
+ fatal("BN_new failed");
+ bits = packet_get_int();
+ packet_get_bignum(client_host_key->e, &elen);
+ packet_get_bignum(client_host_key->n, &nlen);
+
+ if (bits != BN_num_bits(client_host_key->n))
+ error("Warning: keysize mismatch for client_host_key: "
+ "actual %d, announced %d", BN_num_bits(client_host_key->n), bits);
+ packet_integrity_check(plen, (4 + ulen) + 4 + elen + nlen, type);
+
+ authenticated = auth_rhosts_rsa(pw, client_user, client_host_key);
+ RSA_free(client_host_key);
+
+ snprintf(user, sizeof user, " ruser %s", client_user);
+ break;
+
+ case SSH_CMSG_AUTH_RSA:
+ if (!options.rsa_authentication) {
+ verbose("RSA authentication disabled.");
+ break;
+ }
+ /* RSA authentication requested. */
+ n = BN_new();
+ packet_get_bignum(n, &nlen);
+ packet_integrity_check(plen, nlen, type);
+ authenticated = auth_rsa(pw, n);
+ BN_clear_free(n);
+ break;
+
+ case SSH_CMSG_AUTH_PASSWORD:
+ if (!options.password_authentication) {
+ verbose("Password authentication disabled.");
+ break;
+ }
+ /*
+ * Read user password. It is in plain text, but was
+ * transmitted over the encrypted channel so it is
+ * not visible to an outside observer.
+ */
+ password = packet_get_string(&dlen);
+ packet_integrity_check(plen, 4 + dlen, type);
+
+#ifdef USE_PAM
+ /* Do PAM auth with password */
+ authenticated = auth_pam_password(pw, password);
+#else /* USE_PAM */
+ /* Try authentication with the password. */
+ authenticated = auth_password(pw, password);
+#endif /* USE_PAM */
+ memset(password, 0, strlen(password));
+ xfree(password);
+ break;
+
+#ifdef SKEY
+ case SSH_CMSG_AUTH_TIS:
+ debug("rcvd SSH_CMSG_AUTH_TIS");
+ if (options.skey_authentication == 1) {
+ char *skeyinfo = skey_keyinfo(pw->pw_name);
+ if (skeyinfo == NULL) {
+ debug("generating fake skeyinfo for %.100s.", pw->pw_name);
+ skeyinfo = skey_fake_keyinfo(pw->pw_name);
+ }
+ if (skeyinfo != NULL) {
+ /* we send our s/key- in tis-challenge messages */
+ debug("sending challenge '%s'", skeyinfo);
+ packet_start(SSH_SMSG_AUTH_TIS_CHALLENGE);
+ packet_put_string(skeyinfo, strlen(skeyinfo));
+ packet_send();
+ packet_write_wait();
+ continue;
+ }
+ }
+ break;
+ case SSH_CMSG_AUTH_TIS_RESPONSE:
+ debug("rcvd SSH_CMSG_AUTH_TIS_RESPONSE");
+ if (options.skey_authentication == 1) {
+ char *response = packet_get_string(&dlen);
+ debug("skey response == '%s'", response);
+ packet_integrity_check(plen, 4 + dlen, type);
+ authenticated = (skey_haskey(pw->pw_name) == 0 &&
+ skey_passcheck(pw->pw_name, response) != -1);
+ xfree(response);
+ }
+ break;
+#else
+ case SSH_CMSG_AUTH_TIS:
+ /* TIS Authentication is unsupported */
+ log("TIS authentication unsupported.");
+ break;
+#endif
+
+ default:
+ /*
+ * Any unknown messages will be ignored (and failure
+ * returned) during authentication.
+ */
+ log("Unknown message during authentication: type %d", type);
+ break;
+ }
+
+ /*
+ * Check if the user is logging in as root and root logins
+ * are disallowed.
+ * Note that root login is allowed for forced commands.
+ */
+ if (authenticated && pw->pw_uid == 0 && !options.permit_root_login) {
+ if (forced_command) {
+ log("Root login accepted for forced command.");
+ } else {
+ authenticated = 0;
+ log("ROOT LOGIN REFUSED FROM %.200s",
+ get_canonical_hostname());
+ }
+ }
+
+ /* Raise logging level */
+ if (authenticated ||
+ attempt == AUTH_FAIL_LOG ||
+ type == SSH_CMSG_AUTH_PASSWORD)
+ authlog = log;
+
+ authlog("%s %s for %.200s from %.200s port %d%s",
+ authenticated ? "Accepted" : "Failed",
+ get_authname(type),
+ pw->pw_uid == 0 ? "ROOT" : pw->pw_name,
+ get_remote_ipaddr(),
+ get_remote_port(),
+ user);
+
+#ifdef USE_PAM
+ if (authenticated) {
+ if (!do_pam_account(pw->pw_name, client_user)) {
+ if (client_user != NULL) {
+ xfree(client_user);
+ client_user = NULL;
+ }
+ do_fake_authloop1(pw->pw_name);
+ }
+ return;
+ }
+#else /* USE_PAM */
+ if (authenticated) {
+ return;
+ }
+#endif /* USE_PAM */
+
+ if (client_user != NULL) {
+ xfree(client_user);
+ client_user = NULL;
+ }
+
+ if (attempt > AUTH_FAIL_MAX)
+ packet_disconnect(AUTH_FAIL_MSG, pw->pw_name);
+
+ /* Send a message indicating that the authentication attempt failed. */
+ packet_start(SSH_SMSG_FAILURE);
+ packet_send();
+ packet_write_wait();
+ }
+}
+
+/*
+ * Performs authentication of an incoming connection. Session key has already
+ * been exchanged and encryption is enabled.
+ */
+void
+do_authentication()
+{
+ struct passwd *pw, pwcopy;
+ int plen;
+ unsigned int ulen;
+ char *user;
+#ifdef WITH_AIXAUTHENTICATE
+ char *loginmsg;
+#endif /* WITH_AIXAUTHENTICATE */
+
+ /* Get the name of the user that we wish to log in as. */
+ packet_read_expect(&plen, SSH_CMSG_USER);
+
+ /* Get the user name. */
+ user = packet_get_string(&ulen);
+ packet_integrity_check(plen, (4 + ulen), SSH_CMSG_USER);
+
+ setproctitle("%s", user);
+
+#ifdef AFS
+ /* If machine has AFS, set process authentication group. */
+ if (k_hasafs()) {
+ k_setpag();
+ k_unlog();
+ }
+#endif /* AFS */
+
+ /* Verify that the user is a valid user. */
+ pw = getpwnam(user);
+ if (!pw || !allowed_user(pw))
+ do_fake_authloop1(user);
+ xfree(user);
+
+ /* Take a copy of the returned structure. */
+ memset(&pwcopy, 0, sizeof(pwcopy));
+ pwcopy.pw_name = xstrdup(pw->pw_name);
+ pwcopy.pw_passwd = xstrdup(pw->pw_passwd);
+ pwcopy.pw_uid = pw->pw_uid;
+ pwcopy.pw_gid = pw->pw_gid;
+ pwcopy.pw_dir = xstrdup(pw->pw_dir);
+ pwcopy.pw_shell = xstrdup(pw->pw_shell);
+ pw = &pwcopy;
+
+#ifdef USE_PAM
+ start_pam(pw);
+#endif
+
+ /*
+ * If we are not running as root, the user must have the same uid as
+ * the server.
+ */
+ if (getuid() != 0 && pw->pw_uid != getuid())
+ packet_disconnect("Cannot change user when server not running as root.");
+
+ debug("Attempting authentication for %.100s.", pw->pw_name);
+
+ /* If the user has no password, accept authentication immediately. */
+ if (options.password_authentication &&
+#ifdef KRB4
+ (!options.kerberos_authentication || options.kerberos_or_local_passwd) &&
+#endif /* KRB4 */
+#ifdef USE_PAM
+ auth_pam_password(pw, "")) {
+#else /* USE_PAM */
+ auth_password(pw, "")) {
+#endif /* USE_PAM */
+ /* Authentication with empty password succeeded. */
+ log("Login for user %s from %.100s, accepted without authentication.",
+ pw->pw_name, get_remote_ipaddr());
+ } else {
+ /* Loop until the user has been authenticated or the
+ connection is closed, do_authloop() returns only if
+ authentication is successfull */
+ do_authloop(pw);
+ }
+
+ /* The user has been authenticated and accepted. */
+#ifdef WITH_AIXAUTHENTICATE
+ loginsuccess(user,get_canonical_hostname(),"ssh",&loginmsg);
+#endif /* WITH_AIXAUTHENTICATE */
+ packet_start(SSH_SMSG_SUCCESS);
+ packet_send();
+ packet_write_wait();
+
+ /* Perform session preparation. */
+ do_authenticated(pw);
+}
--- /dev/null
+#ifndef AUTH_H
+#define AUTH_H
+
+void do_authentication(void);
+
+#endif
* Auxiliary functions for storing and retrieving various data types to/from
* Buffers.
*
+ * SSH2 packet format added by Markus Friedl
+ *
*/
#include "includes.h"
return 2 + bytes;
}
+/*
+ * Stores an BIGNUM in the buffer in SSH2 format.
+ */
+void
+buffer_put_bignum2(Buffer *buffer, BIGNUM *value)
+{
+ int bytes = BN_num_bytes(value) + 1;
+ unsigned char *buf = xmalloc(bytes);
+ int oi;
+ int hasnohigh = 0;
+ buf[0] = '\0';
+ /* Get the value of in binary */
+ oi = BN_bn2bin(value, buf+1);
+ if (oi != bytes-1)
+ fatal("buffer_put_bignum: BN_bn2bin() failed: oi %d != bin_size %d",
+ oi, bytes);
+ hasnohigh = (buf[1] & 0x80) ? 0 : 1;
+ if (value->neg) {
+ /**XXX should be two's-complement */
+ int i, carry;
+ unsigned char *uc = buf;
+ log("negativ!");
+ for(i = bytes-1, carry = 1; i>=0; i--) {
+ uc[i] ^= 0xff;
+ if(carry)
+ carry = !++uc[i];
+ }
+ }
+ buffer_put_string(buffer, buf+hasnohigh, bytes-hasnohigh);
+ memset(buf, 0, bytes);
+ xfree(buf);
+}
+
+int
+buffer_get_bignum2(Buffer *buffer, BIGNUM *value)
+{
+ /**XXX should be two's-complement */
+ int len;
+ unsigned char *bin = (unsigned char *)buffer_get_string(buffer, (unsigned int *)&len);
+ BN_bin2bn(bin, len, value);
+ xfree(bin);
+ return len;
+}
+
/*
* Returns an integer from the buffer (4 bytes, msb first).
*/
buffer_put_int(buffer, len);
buffer_append(buffer, buf, len);
}
+void
+buffer_put_cstring(Buffer *buffer, const char *s)
+{
+ buffer_put_string(buffer, s, strlen(s));
+}
/*
* Returns a character from the buffer (0 - 255).
* by (bits+7)/8 bytes of binary data, msb first.
*/
void buffer_put_bignum(Buffer * buffer, BIGNUM * value);
+void buffer_put_bignum2(Buffer * buffer, BIGNUM * value);
/* Retrieves an BIGNUM from the buffer. */
int buffer_get_bignum(Buffer * buffer, BIGNUM * value);
+int buffer_get_bignum2(Buffer *buffer, BIGNUM * value);
/* Returns an integer from the buffer (4 bytes, msb first). */
unsigned int buffer_get_int(Buffer * buffer);
/* Stores and arbitrary binary string in the buffer. */
void buffer_put_string(Buffer * buffer, const void *buf, unsigned int len);
+void buffer_put_cstring(Buffer *buffer, const char *s);
#endif /* BUFAUX_H */
/* Max len of agent socket */
#define MAX_SOCKET_NAME 100
+/* default buffer for tcp-fwd-channel */
+#define CHAN_WINDOW_DEFAULT (8*1024)
+#define CHAN_PACKET_DEFAULT (CHAN_WINDOW_DEFAULT/2)
+
/*
* Pointer to an array containing all allocated channels. The array is
* dynamically extended as needed.
* network (which might be behind a firewall).
*/
typedef struct {
- char *host; /* Host name. */
- u_short port; /* Port number. */
+ char *host_to_connect; /* Connect to 'host'. */
+ u_short port_to_connect; /* Connect to 'port'. */
+ u_short listen_port; /* Remote side should listen port number. */
} ForwardPermission;
/* List of all permitted host/port pairs to connect. */
all_opens_permitted = 1;
}
+/* lookup channel by id */
+
+Channel *
+channel_lookup(int id)
+{
+ Channel *c;
+ if (id < 0 && id > channels_alloc) {
+ log("channel_lookup: %d: bad id", id);
+ return NULL;
+ }
+ c = &channels[id];
+ if (c->type == SSH_CHANNEL_FREE) {
+ log("channel_lookup: %d: bad id: channel free", id);
+ return NULL;
+ }
+ return c;
+}
+
/*
* Allocate a new channel object and set its type and socket. This will cause
* remote_name to be freed.
*/
int
-channel_allocate(int type, int sock, char *remote_name)
+channel_new(char *ctype, int type, int rfd, int wfd, int efd,
+ int window, int maxpack, int extended_usage, char *remote_name)
{
int i, found;
Channel *c;
/* Update the maximum file descriptor value. */
- if (sock > channel_max_fd_value)
- channel_max_fd_value = sock;
+ if (rfd > channel_max_fd_value)
+ channel_max_fd_value = rfd;
+ if (wfd > channel_max_fd_value)
+ channel_max_fd_value = wfd;
+ if (efd > channel_max_fd_value)
+ channel_max_fd_value = efd;
/* XXX set close-on-exec -markus */
/* Do initial allocation if this is the first call. */
c = &channels[found];
buffer_init(&c->input);
buffer_init(&c->output);
+ buffer_init(&c->extended);
chan_init_iostates(c);
c->self = found;
c->type = type;
- c->sock = sock;
+ c->ctype = ctype;
+ c->local_window = window;
+ c->local_window_max = window;
+ c->local_consumed = 0;
+ c->local_maxpacket = maxpack;
+ c->remote_window = 0;
+ c->remote_maxpacket = 0;
+ c->rfd = rfd;
+ c->wfd = wfd;
+ c->sock = (rfd == wfd) ? rfd : -1;
+ c->efd = efd;
+ c->extended_usage = extended_usage;
c->remote_id = -1;
c->remote_name = remote_name;
+ c->remote_window = 0;
+ c->remote_maxpacket = 0;
+ c->cb_fn = NULL;
+ c->cb_arg = NULL;
+ c->cb_event = 0;
+ c->dettach_user = NULL;
debug("channel %d: new [%s]", found, remote_name);
return found;
}
+int
+channel_allocate(int type, int sock, char *remote_name)
+{
+ return channel_new("", type, sock, sock, -1, 0, 0, 0, remote_name);
+}
/* Free the channel and close its socket. */
void
-channel_free(int channel)
+channel_free(int id)
{
- if (channel < 0 || channel >= channels_alloc ||
- channels[channel].type == SSH_CHANNEL_FREE)
- packet_disconnect("channel free: bad local channel %d", channel);
-
- if (compat13)
- shutdown(channels[channel].sock, SHUT_RDWR);
- close(channels[channel].sock);
- buffer_free(&channels[channel].input);
- buffer_free(&channels[channel].output);
- channels[channel].type = SSH_CHANNEL_FREE;
- if (channels[channel].remote_name) {
- xfree(channels[channel].remote_name);
- channels[channel].remote_name = NULL;
+ Channel *c = channel_lookup(id);
+ if (c == NULL)
+ packet_disconnect("channel free: bad local channel %d", id);
+ debug("channel_free: channel %d: status: %s", id, channel_open_message());
+ if (c->sock != -1) {
+ shutdown(c->sock, SHUT_RDWR);
+ close(c->sock);
+ }
+ buffer_free(&c->input);
+ buffer_free(&c->output);
+ buffer_free(&c->extended);
+ c->type = SSH_CHANNEL_FREE;
+ if (c->remote_name) {
+ xfree(c->remote_name);
+ c->remote_name = NULL;
}
}
/*
- * This is called just before select() to add any bits relevant to channels
- * in the select bitmasks.
+ * 'channel_pre*' are called just before select() to add any bits relevant to
+ * channels in the select bitmasks.
+ */
+/*
+ * 'channel_post*': perform any appropriate operations for channels which
+ * have events pending.
*/
+typedef void chan_fn(Channel *c, fd_set * readset, fd_set * writeset);
+chan_fn *channel_pre[SSH_CHANNEL_MAX_TYPE];
+chan_fn *channel_post[SSH_CHANNEL_MAX_TYPE];
-void
-channel_prepare_select(fd_set * readset, fd_set * writeset)
+void
+channel_pre_listener(Channel *c, fd_set * readset, fd_set * writeset)
{
- int i;
- Channel *ch;
- unsigned char *ucp;
- unsigned int proto_len, data_len;
+ FD_SET(c->sock, readset);
+}
- for (i = 0; i < channels_alloc; i++) {
- ch = &channels[i];
-redo:
- switch (ch->type) {
- case SSH_CHANNEL_X11_LISTENER:
- case SSH_CHANNEL_PORT_LISTENER:
- case SSH_CHANNEL_AUTH_SOCKET:
- FD_SET(ch->sock, readset);
- break;
+void
+channel_pre_open_13(Channel *c, fd_set * readset, fd_set * writeset)
+{
+ if (buffer_len(&c->input) < packet_get_maxsize())
+ FD_SET(c->sock, readset);
+ if (buffer_len(&c->output) > 0)
+ FD_SET(c->sock, writeset);
+}
- case SSH_CHANNEL_OPEN:
- if (compat13) {
- if (buffer_len(&ch->input) < packet_get_maxsize())
- FD_SET(ch->sock, readset);
- if (buffer_len(&ch->output) > 0)
- FD_SET(ch->sock, writeset);
- break;
- }
- /* test whether sockets are 'alive' for read/write */
- if (ch->istate == CHAN_INPUT_OPEN)
- if (buffer_len(&ch->input) < packet_get_maxsize())
- FD_SET(ch->sock, readset);
- if (ch->ostate == CHAN_OUTPUT_OPEN ||
- ch->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
- if (buffer_len(&ch->output) > 0) {
- FD_SET(ch->sock, writeset);
- } else if (ch->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
- chan_obuf_empty(ch);
- }
- }
- break;
+void
+channel_pre_open_15(Channel *c, fd_set * readset, fd_set * writeset)
+{
+ /* test whether sockets are 'alive' for read/write */
+ if (c->istate == CHAN_INPUT_OPEN)
+ if (buffer_len(&c->input) < packet_get_maxsize())
+ FD_SET(c->sock, readset);
+ if (c->ostate == CHAN_OUTPUT_OPEN ||
+ c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
+ if (buffer_len(&c->output) > 0) {
+ FD_SET(c->sock, writeset);
+ } else if (c->ostate == CHAN_OUTPUT_WAIT_DRAIN) {
+ chan_obuf_empty(c);
+ }
+ }
+}
- case SSH_CHANNEL_INPUT_DRAINING:
- if (!compat13)
- fatal("cannot happen: IN_DRAIN");
- if (buffer_len(&ch->input) == 0) {
- packet_start(SSH_MSG_CHANNEL_CLOSE);
- packet_put_int(ch->remote_id);
- packet_send();
- ch->type = SSH_CHANNEL_CLOSED;
- debug("Closing channel %d after input drain.", ch->self);
- break;
- }
- break;
+void
+channel_pre_input_draining(Channel *c, fd_set * readset, fd_set * writeset)
+{
+ if (buffer_len(&c->input) == 0) {
+ packet_start(SSH_MSG_CHANNEL_CLOSE);
+ packet_put_int(c->remote_id);
+ packet_send();
+ c->type = SSH_CHANNEL_CLOSED;
+ debug("Closing channel %d after input drain.", c->self);
+ }
+}
- case SSH_CHANNEL_OUTPUT_DRAINING:
- if (!compat13)
- fatal("cannot happen: OUT_DRAIN");
- if (buffer_len(&ch->output) == 0) {
- channel_free(i);
- break;
- }
- FD_SET(ch->sock, writeset);
- break;
+void
+channel_pre_output_draining(Channel *c, fd_set * readset, fd_set * writeset)
+{
+ if (buffer_len(&c->output) == 0)
+ channel_free(c->self);
+ else
+ FD_SET(c->sock, writeset);
+}
- case SSH_CHANNEL_X11_OPEN:
- /*
- * This is a special state for X11 authentication
- * spoofing. An opened X11 connection (when
- * authentication spoofing is being done) remains in
- * this state until the first packet has been
- * completely read. The authentication data in that
- * packet is then substituted by the real data if it
- * matches the fake data, and the channel is put into
- * normal mode.
- */
- /* Check if the fixed size part of the packet is in buffer. */
- if (buffer_len(&ch->output) < 12)
- break;
+/*
+ * This is a special state for X11 authentication spoofing. An opened X11
+ * connection (when authentication spoofing is being done) remains in this
+ * state until the first packet has been completely read. The authentication
+ * data in that packet is then substituted by the real data if it matches the
+ * fake data, and the channel is put into normal mode.
+ */
+int
+x11_open_helper(Channel *c)
+{
+ unsigned char *ucp;
+ unsigned int proto_len, data_len;
- /* Parse the lengths of variable-length fields. */
- ucp = (unsigned char *) buffer_ptr(&ch->output);
- if (ucp[0] == 0x42) { /* Byte order MSB first. */
- proto_len = 256 * ucp[6] + ucp[7];
- data_len = 256 * ucp[8] + ucp[9];
- } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
- proto_len = ucp[6] + 256 * ucp[7];
- data_len = ucp[8] + 256 * ucp[9];
- } else {
- debug("Initial X11 packet contains bad byte order byte: 0x%x",
- ucp[0]);
- ch->type = SSH_CHANNEL_OPEN;
- goto reject;
- }
+ /* Check if the fixed size part of the packet is in buffer. */
+ if (buffer_len(&c->output) < 12)
+ return 0;
+
+ /* Parse the lengths of variable-length fields. */
+ ucp = (unsigned char *) buffer_ptr(&c->output);
+ if (ucp[0] == 0x42) { /* Byte order MSB first. */
+ proto_len = 256 * ucp[6] + ucp[7];
+ data_len = 256 * ucp[8] + ucp[9];
+ } else if (ucp[0] == 0x6c) { /* Byte order LSB first. */
+ proto_len = ucp[6] + 256 * ucp[7];
+ data_len = ucp[8] + 256 * ucp[9];
+ } else {
+ debug("Initial X11 packet contains bad byte order byte: 0x%x",
+ ucp[0]);
+ return -1;
+ }
- /* Check if the whole packet is in buffer. */
- if (buffer_len(&ch->output) <
- 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
- break;
+ /* Check if the whole packet is in buffer. */
+ if (buffer_len(&c->output) <
+ 12 + ((proto_len + 3) & ~3) + ((data_len + 3) & ~3))
+ return 0;
- /* Check if authentication protocol matches. */
- if (proto_len != strlen(x11_saved_proto) ||
- memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) {
- debug("X11 connection uses different authentication protocol.");
- ch->type = SSH_CHANNEL_OPEN;
- goto reject;
- }
- /* Check if authentication data matches our fake data. */
- if (data_len != x11_fake_data_len ||
- memcmp(ucp + 12 + ((proto_len + 3) & ~3),
- x11_fake_data, x11_fake_data_len) != 0) {
- debug("X11 auth data does not match fake data.");
- ch->type = SSH_CHANNEL_OPEN;
- goto reject;
- }
- /* Check fake data length */
- if (x11_fake_data_len != x11_saved_data_len) {
- error("X11 fake_data_len %d != saved_data_len %d",
- x11_fake_data_len, x11_saved_data_len);
- ch->type = SSH_CHANNEL_OPEN;
- goto reject;
- }
- /*
- * Received authentication protocol and data match
- * our fake data. Substitute the fake data with real
- * data.
- */
- memcpy(ucp + 12 + ((proto_len + 3) & ~3),
- x11_saved_data, x11_saved_data_len);
+ /* Check if authentication protocol matches. */
+ if (proto_len != strlen(x11_saved_proto) ||
+ memcmp(ucp + 12, x11_saved_proto, proto_len) != 0) {
+ debug("X11 connection uses different authentication protocol.");
+ return -1;
+ }
+ /* Check if authentication data matches our fake data. */
+ if (data_len != x11_fake_data_len ||
+ memcmp(ucp + 12 + ((proto_len + 3) & ~3),
+ x11_fake_data, x11_fake_data_len) != 0) {
+ debug("X11 auth data does not match fake data.");
+ return -1;
+ }
+ /* Check fake data length */
+ if (x11_fake_data_len != x11_saved_data_len) {
+ error("X11 fake_data_len %d != saved_data_len %d",
+ x11_fake_data_len, x11_saved_data_len);
+ return -1;
+ }
+ /*
+ * Received authentication protocol and data match
+ * our fake data. Substitute the fake data with real
+ * data.
+ */
+ memcpy(ucp + 12 + ((proto_len + 3) & ~3),
+ x11_saved_data, x11_saved_data_len);
+ return 1;
+}
- /* Start normal processing for the channel. */
- ch->type = SSH_CHANNEL_OPEN;
- goto redo;
+void
+channel_pre_x11_open_13(Channel *c, fd_set * readset, fd_set * writeset)
+{
+ int ret = x11_open_helper(c);
+ if (ret == 1) {
+ /* Start normal processing for the channel. */
+ c->type = SSH_CHANNEL_OPEN;
+ } else if (ret == -1) {
+ /*
+ * We have received an X11 connection that has bad
+ * authentication information.
+ */
+ log("X11 connection rejected because of wrong authentication.\r\n");
+ buffer_clear(&c->input);
+ buffer_clear(&c->output);
+ close(c->sock);
+ c->sock = -1;
+ c->type = SSH_CHANNEL_CLOSED;
+ packet_start(SSH_MSG_CHANNEL_CLOSE);
+ packet_put_int(c->remote_id);
+ packet_send();
+ }
+}
- reject:
- /*
- * We have received an X11 connection that has bad
- * authentication information.
- */
- log("X11 connection rejected because of wrong authentication.\r\n");
- buffer_clear(&ch->input);
- buffer_clear(&ch->output);
- if (compat13) {
- close(ch->sock);
- ch->sock = -1;
- ch->type = SSH_CHANNEL_CLOSED;
- packet_start(SSH_MSG_CHANNEL_CLOSE);
- packet_put_int(ch->remote_id);
- packet_send();
- } else {
- debug("X11 rejected %d i%d/o%d", ch->self, ch->istate, ch->ostate);
- chan_read_failed(ch);
- chan_write_failed(ch);
- debug("X11 rejected %d i%d/o%d", ch->self, ch->istate, ch->ostate);
- }
- break;
+void
+channel_pre_x11_open_15(Channel *c, fd_set * readset, fd_set * writeset)
+{
+ int ret = x11_open_helper(c);
+ if (ret == 1) {
+ c->type = SSH_CHANNEL_OPEN;
+ } else if (ret == -1) {
+ debug("X11 rejected %d i%d/o%d", c->self, c->istate, c->ostate);
+ chan_read_failed(c);
+ chan_write_failed(c);
+ debug("X11 closed %d i%d/o%d", c->self, c->istate, c->ostate);
+ }
+}
- case SSH_CHANNEL_FREE:
- default:
- continue;
+/* This is our fake X11 server socket. */
+void
+channel_post_x11_listener(Channel *c, fd_set * readset, fd_set * writeset)
+{
+ struct sockaddr addr;
+ int newsock, newch;
+ socklen_t addrlen;
+ char buf[16384], *remote_hostname;
+
+ if (FD_ISSET(c->sock, readset)) {
+ debug("X11 connection requested.");
+ addrlen = sizeof(addr);
+ newsock = accept(c->sock, &addr, &addrlen);
+ if (newsock < 0) {
+ error("accept: %.100s", strerror(errno));
+ return;
}
+ remote_hostname = get_remote_hostname(newsock);
+ snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
+ remote_hostname, get_peer_port(newsock));
+ xfree(remote_hostname);
+ newch = channel_allocate(SSH_CHANNEL_OPENING, newsock,
+ xstrdup(buf));
+ packet_start(SSH_SMSG_X11_OPEN);
+ packet_put_int(newch);
+ if (have_hostname_in_open)
+ packet_put_string(buf, strlen(buf));
+ packet_send();
}
}
/*
- * After select, perform any appropriate operations for channels which have
- * events pending.
+ * This socket is listening for connections to a forwarded TCP/IP port.
*/
+void
+channel_post_port_listener(Channel *c, fd_set * readset, fd_set * writeset)
+{
+ struct sockaddr addr;
+ int newsock, newch;
+ socklen_t addrlen;
+ char buf[1024], *remote_hostname;
+ int remote_port;
+
+ if (FD_ISSET(c->sock, readset)) {
+ debug("Connection to port %d forwarding "
+ "to %.100s port %d requested.",
+ c->listening_port, c->path, c->host_port);
+ addrlen = sizeof(addr);
+ newsock = accept(c->sock, &addr, &addrlen);
+ if (newsock < 0) {
+ error("accept: %.100s", strerror(errno));
+ return;
+ }
+ remote_hostname = get_remote_hostname(newsock);
+ remote_port = get_peer_port(newsock);
+ snprintf(buf, sizeof buf,
+ "listen port %d for %.100s port %d, "
+ "connect from %.200s port %d",
+ c->listening_port, c->path, c->host_port,
+ remote_hostname, remote_port);
+ newch = channel_new("direct-tcpip",
+ SSH_CHANNEL_OPENING, newsock, newsock, -1,
+ c->local_window_max, c->local_maxpacket,
+ 0, xstrdup(buf));
+
+ packet_start(SSH_MSG_PORT_OPEN);
+ packet_put_int(newch);
+ packet_put_string(c->path, strlen(c->path));
+ packet_put_int(c->host_port);
+ if (have_hostname_in_open) {
+ packet_put_string(buf, strlen(buf));
+ }
+ packet_send();
+ xfree(remote_hostname);
+ }
+}
-void
-channel_after_select(fd_set * readset, fd_set * writeset)
+/*
+ * This is the authentication agent socket listening for connections from
+ * clients.
+ */
+void
+channel_post_auth_listener(Channel *c, fd_set * readset, fd_set * writeset)
{
struct sockaddr addr;
- int newsock, i, newch, len;
+ int newsock, newch;
socklen_t addrlen;
- Channel *ch;
- char buf[16384], *remote_hostname;
- /* Loop over all channels... */
- for (i = 0; i < channels_alloc; i++) {
- ch = &channels[i];
- switch (ch->type) {
- case SSH_CHANNEL_X11_LISTENER:
- /* This is our fake X11 server socket. */
- if (FD_ISSET(ch->sock, readset)) {
- debug("X11 connection requested.");
- addrlen = sizeof(addr);
- newsock = accept(ch->sock, &addr, &addrlen);
- if (newsock < 0) {
- error("accept: %.100s", strerror(errno));
- break;
- }
- remote_hostname = get_remote_hostname(newsock);
- snprintf(buf, sizeof buf, "X11 connection from %.200s port %d",
- remote_hostname, get_peer_port(newsock));
- xfree(remote_hostname);
- newch = channel_allocate(SSH_CHANNEL_OPENING, newsock,
- xstrdup(buf));
- packet_start(SSH_SMSG_X11_OPEN);
- packet_put_int(newch);
- if (have_hostname_in_open)
- packet_put_string(buf, strlen(buf));
- packet_send();
- }
- break;
+ if (FD_ISSET(c->sock, readset)) {
+ addrlen = sizeof(addr);
+ newsock = accept(c->sock, &addr, &addrlen);
+ if (newsock < 0) {
+ error("accept from auth socket: %.100s", strerror(errno));
+ return;
+ }
+ newch = channel_allocate(SSH_CHANNEL_OPENING, newsock,
+ xstrdup("accepted auth socket"));
+ packet_start(SSH_SMSG_AGENT_OPEN);
+ packet_put_int(newch);
+ packet_send();
+ }
+}
- case SSH_CHANNEL_PORT_LISTENER:
- /*
- * This socket is listening for connections to a
- * forwarded TCP/IP port.
- */
- if (FD_ISSET(ch->sock, readset)) {
- debug("Connection to port %d forwarding to %.100s port %d requested.",
- ch->listening_port, ch->path, ch->host_port);
- addrlen = sizeof(addr);
- newsock = accept(ch->sock, &addr, &addrlen);
- if (newsock < 0) {
- error("accept: %.100s", strerror(errno));
- break;
- }
- remote_hostname = get_remote_hostname(newsock);
- snprintf(buf, sizeof buf, "listen port %d for %.100s port %d, connect from %.200s port %d",
- ch->listening_port, ch->path, ch->host_port,
- remote_hostname, get_peer_port(newsock));
- xfree(remote_hostname);
- newch = channel_allocate(SSH_CHANNEL_OPENING, newsock,
- xstrdup(buf));
- packet_start(SSH_MSG_PORT_OPEN);
- packet_put_int(newch);
- packet_put_string(ch->path, strlen(ch->path));
- packet_put_int(ch->host_port);
- if (have_hostname_in_open)
- packet_put_string(buf, strlen(buf));
- packet_send();
+int
+channel_handle_rfd(Channel *c, fd_set * readset, fd_set * writeset)
+{
+ char buf[16*1024];
+ int len;
+
+ if (c->rfd != -1 &&
+ FD_ISSET(c->rfd, readset)) {
+ len = read(c->rfd, buf, sizeof(buf));
+ if (len <= 0) {
+ debug("channel %d: read<0 rfd %d len %d",
+ c->self, c->rfd, len);
+ if (compat13) {
+ buffer_consume(&c->output, buffer_len(&c->output));
+ c->type = SSH_CHANNEL_INPUT_DRAINING;
+ debug("Channel %d status set to input draining.", c->self);
+ } else {
+ chan_read_failed(c);
}
- break;
-
- case SSH_CHANNEL_AUTH_SOCKET:
- /*
- * This is the authentication agent socket listening
- * for connections from clients.
- */
- if (FD_ISSET(ch->sock, readset)) {
- addrlen = sizeof(addr);
- newsock = accept(ch->sock, &addr, &addrlen);
- if (newsock < 0) {
- error("accept from auth socket: %.100s", strerror(errno));
- break;
- }
- newch = channel_allocate(SSH_CHANNEL_OPENING, newsock,
- xstrdup("accepted auth socket"));
- packet_start(SSH_SMSG_AGENT_OPEN);
- packet_put_int(newch);
- packet_send();
+ return -1;
+ }
+ buffer_append(&c->input, buf, len);
+ }
+ return 1;
+}
+int
+channel_handle_wfd(Channel *c, fd_set * readset, fd_set * writeset)
+{
+ int len;
+
+ /* Send buffered output data to the socket. */
+ if (c->wfd != -1 &&
+ FD_ISSET(c->wfd, writeset) &&
+ buffer_len(&c->output) > 0) {
+ len = write(c->wfd, buffer_ptr(&c->output),
+ buffer_len(&c->output));
+ if (len <= 0) {
+ if (compat13) {
+ buffer_consume(&c->output, buffer_len(&c->output));
+ debug("Channel %d status set to input draining.", c->self);
+ c->type = SSH_CHANNEL_INPUT_DRAINING;
+ } else {
+ chan_write_failed(c);
}
- break;
+ return -1;
+ }
+ buffer_consume(&c->output, len);
+ }
+ return 1;
+}
- case SSH_CHANNEL_OPEN:
- /*
- * This is an open two-way communication channel. It
- * is not of interest to us at this point what kind
- * of data is being transmitted.
- */
+void
+channel_post_open_1(Channel *c, fd_set * readset, fd_set * writeset)
+{
+ channel_handle_rfd(c, readset, writeset);
+ channel_handle_wfd(c, readset, writeset);
+}
- /*
- * Read available incoming data and append it to
- * buffer; shutdown socket, if read or write failes
- */
- if (FD_ISSET(ch->sock, readset)) {
- len = read(ch->sock, buf, sizeof(buf));
- if (len <= 0) {
- if (compat13) {
- buffer_consume(&ch->output, buffer_len(&ch->output));
- ch->type = SSH_CHANNEL_INPUT_DRAINING;
- debug("Channel %d status set to input draining.", i);
- } else {
- chan_read_failed(ch);
- }
- break;
- }
- buffer_append(&ch->input, buf, len);
- }
- /* Send buffered output data to the socket. */
- if (FD_ISSET(ch->sock, writeset) && buffer_len(&ch->output) > 0) {
- len = write(ch->sock, buffer_ptr(&ch->output),
- buffer_len(&ch->output));
- if (len <= 0) {
- if (compat13) {
- buffer_consume(&ch->output, buffer_len(&ch->output));
- debug("Channel %d status set to input draining.", i);
- ch->type = SSH_CHANNEL_INPUT_DRAINING;
- } else {
- chan_write_failed(ch);
- }
- break;
- }
- buffer_consume(&ch->output, len);
- }
- break;
+void
+channel_post_output_drain_13(Channel *c, fd_set * readset, fd_set * writeset)
+{
+ int len;
+ /* Send buffered output data to the socket. */
+ if (FD_ISSET(c->sock, writeset) && buffer_len(&c->output) > 0) {
+ len = write(c->sock, buffer_ptr(&c->output),
+ buffer_len(&c->output));
+ if (len <= 0)
+ buffer_consume(&c->output, buffer_len(&c->output));
+ else
+ buffer_consume(&c->output, len);
+ }
+}
- case SSH_CHANNEL_OUTPUT_DRAINING:
- if (!compat13)
- fatal("cannot happen: OUT_DRAIN");
- /* Send buffered output data to the socket. */
- if (FD_ISSET(ch->sock, writeset) && buffer_len(&ch->output) > 0) {
- len = write(ch->sock, buffer_ptr(&ch->output),
- buffer_len(&ch->output));
- if (len <= 0)
- buffer_consume(&ch->output, buffer_len(&ch->output));
- else
- buffer_consume(&ch->output, len);
- }
- break;
+void
+channel_handler_init_13(void)
+{
+ channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_13;
+ channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_13;
+ channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
+ channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
+ channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
+ channel_pre[SSH_CHANNEL_INPUT_DRAINING] = &channel_pre_input_draining;
+ channel_pre[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_pre_output_draining;
+
+ channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_1;
+ channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
+ channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
+ channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
+ channel_post[SSH_CHANNEL_OUTPUT_DRAINING] = &channel_post_output_drain_13;
+}
- case SSH_CHANNEL_X11_OPEN:
- case SSH_CHANNEL_FREE:
- default:
+void
+channel_handler_init_15(void)
+{
+ channel_pre[SSH_CHANNEL_OPEN] = &channel_pre_open_15;
+ channel_pre[SSH_CHANNEL_X11_OPEN] = &channel_pre_x11_open_15;
+ channel_pre[SSH_CHANNEL_X11_LISTENER] = &channel_pre_listener;
+ channel_pre[SSH_CHANNEL_PORT_LISTENER] = &channel_pre_listener;
+ channel_pre[SSH_CHANNEL_AUTH_SOCKET] = &channel_pre_listener;
+
+ channel_post[SSH_CHANNEL_X11_LISTENER] = &channel_post_x11_listener;
+ channel_post[SSH_CHANNEL_PORT_LISTENER] = &channel_post_port_listener;
+ channel_post[SSH_CHANNEL_AUTH_SOCKET] = &channel_post_auth_listener;
+ channel_post[SSH_CHANNEL_OPEN] = &channel_post_open_1;
+}
+
+void
+channel_handler_init(void)
+{
+ int i;
+ for(i = 0; i < SSH_CHANNEL_MAX_TYPE; i++) {
+ channel_pre[i] = NULL;
+ channel_post[i] = NULL;
+ }
+ if (compat13)
+ channel_handler_init_13();
+ else
+ channel_handler_init_15();
+}
+
+void
+channel_handler(chan_fn *ftab[], fd_set * readset, fd_set * writeset)
+{
+ static int did_init = 0;
+ int i;
+ Channel *c;
+
+ if (!did_init) {
+ channel_handler_init();
+ did_init = 1;
+ }
+ for (i = 0; i < channels_alloc; i++) {
+ c = &channels[i];
+ if (c->type == SSH_CHANNEL_FREE)
continue;
- }
+ if (ftab[c->type] == NULL)
+ continue;
+ (*ftab[c->type])(c, readset, writeset);
+ if (!compat13)
+ chan_delete_if_full_closed(c);
}
}
+void
+channel_prepare_select(fd_set * readset, fd_set * writeset)
+{
+ channel_handler(channel_pre, readset, writeset);
+}
+
+void
+channel_after_select(fd_set * readset, fd_set * writeset)
+{
+ channel_handler(channel_post, readset, writeset);
+}
+
/* If there is data to send to the connection, send some of it now. */
void
channel_output_poll()
{
int len, i;
- Channel *ch;
+ Channel *c;
for (i = 0; i < channels_alloc; i++) {
- ch = &channels[i];
+ c = &channels[i];
/* We are only interested in channels that can have buffered incoming data. */
if (compat13) {
- if (ch->type != SSH_CHANNEL_OPEN &&
- ch->type != SSH_CHANNEL_INPUT_DRAINING)
+ if (c->type != SSH_CHANNEL_OPEN &&
+ c->type != SSH_CHANNEL_INPUT_DRAINING)
continue;
} else {
- if (ch->type != SSH_CHANNEL_OPEN)
+ if (c->type != SSH_CHANNEL_OPEN)
continue;
- if (ch->istate != CHAN_INPUT_OPEN &&
- ch->istate != CHAN_INPUT_WAIT_DRAIN)
+ if (c->istate != CHAN_INPUT_OPEN &&
+ c->istate != CHAN_INPUT_WAIT_DRAIN)
continue;
}
/* Get the amount of buffered data for this channel. */
- len = buffer_len(&ch->input);
+ len = buffer_len(&c->input);
if (len > 0) {
/* Send some data for the other side over the secure connection. */
if (packet_is_interactive()) {
len = 512;
} else {
/* Keep the packets at reasonable size. */
- if (len > packet_get_maxsize()/2)
+ if (len > packet_get_maxsize())
len = packet_get_maxsize()/2;
}
- packet_start(SSH_MSG_CHANNEL_DATA);
- packet_put_int(ch->remote_id);
- packet_put_string(buffer_ptr(&ch->input), len);
- packet_send();
- buffer_consume(&ch->input, len);
- } else if (ch->istate == CHAN_INPUT_WAIT_DRAIN) {
+ if (len > 0) {
+ packet_start(SSH_MSG_CHANNEL_DATA);
+ packet_put_int(c->remote_id);
+ packet_put_string(buffer_ptr(&c->input), len);
+ packet_send();
+ buffer_consume(&c->input, len);
+ c->remote_window -= len;
+debug("channel %d: send data len %d", c->self, len);
+ }
+ } else if (c->istate == CHAN_INPUT_WAIT_DRAIN) {
if (compat13)
fatal("cannot happen: istate == INPUT_WAIT_DRAIN for proto 1.3");
/*
* input-buffer is empty and read-socket shutdown:
* tell peer, that we will not send more data: send IEOF
*/
- chan_ibuf_empty(ch);
+ chan_ibuf_empty(c);
}
}
}
*/
void
-channel_input_data(int payload_len)
+channel_input_data(int type, int plen)
{
int id;
char *data;
unsigned int data_len;
- Channel *ch;
+ Channel *c;
/* Get the channel number and verify it. */
id = packet_get_int();
- if (id < 0 || id >= channels_alloc)
+ c = channel_lookup(id);
+ if (c == NULL)
packet_disconnect("Received data for nonexistent channel %d.", id);
- ch = &channels[id];
-
- if (ch->type == SSH_CHANNEL_FREE)
- packet_disconnect("Received data for free channel %d.", ch->self);
/* Ignore any data for non-open channels (might happen on close) */
- if (ch->type != SSH_CHANNEL_OPEN &&
- ch->type != SSH_CHANNEL_X11_OPEN)
+ if (c->type != SSH_CHANNEL_OPEN &&
+ c->type != SSH_CHANNEL_X11_OPEN)
return;
/* same for protocol 1.5 if output end is no longer open */
- if (!compat13 && ch->ostate != CHAN_OUTPUT_OPEN)
+ if (!compat13 && c->ostate != CHAN_OUTPUT_OPEN)
return;
/* Get the data. */
data = packet_get_string(&data_len);
- packet_integrity_check(payload_len, 4 + 4 + data_len, SSH_MSG_CHANNEL_DATA);
- buffer_append(&ch->output, data, data_len);
+
+ packet_integrity_check(plen, 4 + 4 + data_len, SSH_MSG_CHANNEL_DATA);
+ buffer_append(&c->output, data, data_len);
xfree(data);
}
channel_not_very_much_buffered_data()
{
unsigned int i;
- Channel *ch;
+ Channel *c;
for (i = 0; i < channels_alloc; i++) {
- ch = &channels[i];
- if (ch->type == SSH_CHANNEL_OPEN) {
- if (buffer_len(&ch->input) > packet_get_maxsize())
+ c = &channels[i];
+ if (c->type == SSH_CHANNEL_OPEN) {
+ if (buffer_len(&c->input) > packet_get_maxsize()) {
+ debug("channel %d: big input buffer %d",
+ c->self, buffer_len(&c->input));
return 0;
- if (buffer_len(&ch->output) > packet_get_maxsize())
+ }
+ if (buffer_len(&c->output) > packet_get_maxsize()) {
+ debug("channel %d: big output buffer %d",
+ c->self, buffer_len(&c->output));
return 0;
+ }
}
}
return 1;
}
-/* This is called after receiving CHANNEL_CLOSE/IEOF. */
+void
+channel_input_ieof(int type, int plen)
+{
+ int id;
+ Channel *c;
+
+ packet_integrity_check(plen, 4, type);
+
+ id = packet_get_int();
+ c = channel_lookup(id);
+ if (c == NULL)
+ packet_disconnect("Received ieof for nonexistent channel %d.", id);
+ chan_rcvd_ieof(c);
+}
void
-channel_input_close()
+channel_input_close(int type, int plen)
{
- int channel;
+ int id;
+ Channel *c;
- /* Get the channel number and verify it. */
- channel = packet_get_int();
- if (channel < 0 || channel >= channels_alloc ||
- channels[channel].type == SSH_CHANNEL_FREE)
- packet_disconnect("Received data for nonexistent channel %d.", channel);
-
- if (!compat13) {
- /* proto version 1.5 overloads CLOSE with IEOF */
- chan_rcvd_ieof(&channels[channel]);
- return;
- }
+ packet_integrity_check(plen, 4, type);
+
+ id = packet_get_int();
+ c = channel_lookup(id);
+ if (c == NULL)
+ packet_disconnect("Received close for nonexistent channel %d.", id);
/*
* Send a confirmation that we have closed the channel and no more
* data is coming for it.
*/
packet_start(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION);
- packet_put_int(channels[channel].remote_id);
+ packet_put_int(c->remote_id);
packet_send();
/*
* no-one to receive the confirmation. The channel gets freed when
* the confirmation arrives.
*/
- if (channels[channel].type != SSH_CHANNEL_CLOSED) {
+ if (c->type != SSH_CHANNEL_CLOSED) {
/*
* Not a closed channel - mark it as draining, which will
* cause it to be freed later.
*/
- buffer_consume(&channels[channel].input,
- buffer_len(&channels[channel].input));
- channels[channel].type = SSH_CHANNEL_OUTPUT_DRAINING;
+ buffer_consume(&c->input, buffer_len(&c->input));
+ c->type = SSH_CHANNEL_OUTPUT_DRAINING;
}
}
-/* This is called after receiving CHANNEL_CLOSE_CONFIRMATION/OCLOSE. */
-
+/* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */
void
-channel_input_close_confirmation()
+channel_input_oclose(int type, int plen)
{
- int channel;
-
- /* Get the channel number and verify it. */
- channel = packet_get_int();
- if (channel < 0 || channel >= channels_alloc)
- packet_disconnect("Received close confirmation for out-of-range channel %d.",
- channel);
-
- if (!compat13) {
- /* proto version 1.5 overloads CLOSE_CONFIRMATION with OCLOSE */
- chan_rcvd_oclose(&channels[channel]);
- return;
- }
- if (channels[channel].type != SSH_CHANNEL_CLOSED)
- packet_disconnect("Received close confirmation for non-closed channel %d (type %d).",
- channel, channels[channel].type);
-
- /* Free the channel. */
- channel_free(channel);
+ int id = packet_get_int();
+ Channel *c = channel_lookup(id);
+ packet_integrity_check(plen, 4, type);
+ if (c == NULL)
+ packet_disconnect("Received oclose for nonexistent channel %d.", id);
+ chan_rcvd_oclose(c);
}
-/* This is called after receiving CHANNEL_OPEN_CONFIRMATION. */
+void
+channel_input_close_confirmation(int type, int plen)
+{
+ int id = packet_get_int();
+ Channel *c = channel_lookup(id);
+
+ if (c == NULL)
+ packet_disconnect("Received close confirmation for "
+ "out-of-range channel %d.", id);
+ if (c->type != SSH_CHANNEL_CLOSED)
+ packet_disconnect("Received close confirmation for "
+ "non-closed channel %d (type %d).", id, c->type);
+ channel_free(c->self);
+}
void
-channel_input_open_confirmation()
+channel_input_open_confirmation(int type, int plen)
{
- int channel, remote_channel;
+ int id, remote_id;
+ Channel *c;
- /* Get the channel number and verify it. */
- channel = packet_get_int();
- if (channel < 0 || channel >= channels_alloc ||
- channels[channel].type != SSH_CHANNEL_OPENING)
- packet_disconnect("Received open confirmation for non-opening channel %d.",
- channel);
+ packet_integrity_check(plen, 4 + 4, type);
- /* Get remote side's id for this channel. */
- remote_channel = packet_get_int();
+ id = packet_get_int();
+ c = channel_lookup(id);
+ if (c==NULL || c->type != SSH_CHANNEL_OPENING)
+ packet_disconnect("Received open confirmation for "
+ "non-opening channel %d.", id);
+ remote_id = packet_get_int();
/* Record the remote channel number and mark that the channel is now open. */
- channels[channel].remote_id = remote_channel;
- channels[channel].type = SSH_CHANNEL_OPEN;
+ c->remote_id = remote_id;
+ c->type = SSH_CHANNEL_OPEN;
}
-/* This is called after receiving CHANNEL_OPEN_FAILURE from the other side. */
-
void
-channel_input_open_failure()
+channel_input_open_failure(int type, int plen)
{
- int channel;
+ int id;
+ Channel *c;
- /* Get the channel number and verify it. */
- channel = packet_get_int();
- if (channel < 0 || channel >= channels_alloc ||
- channels[channel].type != SSH_CHANNEL_OPENING)
- packet_disconnect("Received open failure for non-opening channel %d.",
- channel);
+ packet_integrity_check(plen, 4, type);
+
+ id = packet_get_int();
+ c = channel_lookup(id);
+
+ if (c==NULL || c->type != SSH_CHANNEL_OPENING)
+ packet_disconnect("Received open failure for "
+ "non-opening channel %d.", id);
/* Free the channel. This will also close the socket. */
- channel_free(channel);
+ channel_free(id);
}
/*
case SSH_CHANNEL_X11_OPEN:
case SSH_CHANNEL_INPUT_DRAINING:
case SSH_CHANNEL_OUTPUT_DRAINING:
- snprintf(buf, sizeof buf, " #%d %.300s (t%d r%d i%d/%d o%d/%d)\r\n",
+ snprintf(buf, sizeof buf, " #%d %.300s (t%d r%d i%d/%d o%d/%d fd %d/%d)\r\n",
c->self, c->remote_name,
c->type, c->remote_id,
c->istate, buffer_len(&c->input),
- c->ostate, buffer_len(&c->output));
+ c->ostate, buffer_len(&c->output),
+ c->rfd, c->wfd);
buffer_append(&buffer, buf, strlen(buf));
continue;
default:
- fatal("channel_still_open: bad channel type %d", c->type);
+ fatal("channel_open_message: bad channel type %d", c->type);
/* NOTREACHED */
}
}
continue;
}
/* Allocate a channel number for the socket. */
- ch = channel_allocate(SSH_CHANNEL_PORT_LISTENER, sock,
- xstrdup("port listener"));
+ ch = channel_new(
+ "port listener", SSH_CHANNEL_PORT_LISTENER,
+ sock, sock, -1,
+ CHAN_WINDOW_DEFAULT, CHAN_PACKET_DEFAULT,
+ 0, xstrdup("port listener"));
strlcpy(channels[ch].path, host, sizeof(channels[ch].path));
channels[ch].host_port = host_port;
channels[ch].listening_port = port;
*/
void
-channel_request_remote_forwarding(u_short port, const char *host,
- u_short remote_port)
+channel_request_remote_forwarding(u_short listen_port, const char *host_to_connect,
+ u_short port_to_connect)
{
int payload_len;
/* Record locally that connection to this host/port is permitted. */
if (num_permitted_opens >= SSH_MAX_FORWARDS_PER_DIRECTION)
fatal("channel_request_remote_forwarding: too many forwards");
- permitted_opens[num_permitted_opens].host = xstrdup(host);
- permitted_opens[num_permitted_opens].port = remote_port;
+ permitted_opens[num_permitted_opens].host_to_connect = xstrdup(host_to_connect);
+ permitted_opens[num_permitted_opens].port_to_connect = port_to_connect;
+ permitted_opens[num_permitted_opens].listen_port = listen_port;
num_permitted_opens++;
/* Send the forward request to the remote side. */
packet_start(SSH_CMSG_PORT_FORWARD_REQUEST);
- packet_put_int(port);
- packet_put_string(host, strlen(host));
- packet_put_int(remote_port);
+ packet_put_int(port_to_connect);
+ packet_put_string(host_to_connect, strlen(host_to_connect));
+ packet_put_int(listen_port);
packet_send();
packet_write_wait();
-
/*
* Wait for response from the remote side. It will send a disconnect
* message on failure, and we will never see it here.
xfree(hostname);
}
-/*
- * This is called after receiving PORT_OPEN message. This attempts to
- * connect to the given host:port, and sends back CHANNEL_OPEN_CONFIRMATION
- * or CHANNEL_OPEN_FAILURE.
- */
-
-void
-channel_input_port_open(int payload_len)
+/* XXX move to aux.c */
+int
+channel_connect_to(const char *host, u_short host_port)
{
- int remote_channel, sock = 0, newch, i;
- u_short host_port;
- char *host, *originator_string;
- unsigned int host_len, originator_len;
struct addrinfo hints, *ai, *aitop;
char ntop[NI_MAXHOST], strport[NI_MAXSERV];
int gaierr;
-
- /* Get remote channel number. */
- remote_channel = packet_get_int();
-
- /* Get host name to connect to. */
- host = packet_get_string(&host_len);
-
- /* Get port to connect to. */
- host_port = packet_get_int();
-
- /* Get remote originator name. */
- if (have_hostname_in_open) {
- originator_string = packet_get_string(&originator_len);
- originator_len += 4; /* size of packet_int */
- } else {
- originator_string = xstrdup("unknown (remote did not supply name)");
- originator_len = 0; /* no originator supplied */
- }
-
- packet_integrity_check(payload_len,
- 4 + 4 + host_len + 4 + originator_len,
- SSH_MSG_PORT_OPEN);
-
- /* Check if opening that port is permitted. */
- if (!all_opens_permitted) {
- /* Go trough all permitted ports. */
- for (i = 0; i < num_permitted_opens; i++)
- if (permitted_opens[i].port == host_port &&
- strcmp(permitted_opens[i].host, host) == 0)
- break;
-
- /* Check if we found the requested port among those permitted. */
- if (i >= num_permitted_opens) {
- /* The port is not permitted. */
- log("Received request to connect to %.100s:%d, but the request was denied.",
- host, host_port);
- packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
- packet_put_int(remote_channel);
- packet_send();
- }
- }
+ int sock = -1;
memset(&hints, 0, sizeof(hints));
hints.ai_family = IPv4or6;
snprintf(strport, sizeof strport, "%d", host_port);
if ((gaierr = getaddrinfo(host, strport, &hints, &aitop)) != 0) {
error("%.100s: unknown host (%s)", host, gai_strerror(gaierr));
- goto fail;
+ return -1;
}
-
for (ai = aitop; ai; ai = ai->ai_next) {
if (ai->ai_family != AF_INET && ai->ai_family != AF_INET6)
continue;
if (getnameinfo(ai->ai_addr, ai->ai_addrlen, ntop, sizeof(ntop),
strport, sizeof(strport), NI_NUMERICHOST|NI_NUMERICSERV) != 0) {
- error("channel_input_port_open: getnameinfo failed");
+ error("channel_connect_to: getnameinfo failed");
continue;
}
/* Create the socket. */
}
freeaddrinfo(aitop);
-
if (!ai) {
error("connect %.100s port %d: failed.", host, host_port);
- goto fail;
+ return -1;
}
+ /* success */
+ return sock;
+}
- /* Successful connection. */
+/*
+ * This is called after receiving PORT_OPEN message. This attempts to
+ * connect to the given host:port, and sends back CHANNEL_OPEN_CONFIRMATION
+ * or CHANNEL_OPEN_FAILURE.
+ */
- /* Allocate a channel for this connection. */
- newch = channel_allocate(SSH_CHANNEL_OPEN, sock, originator_string);
- channels[newch].remote_id = remote_channel;
+void
+channel_input_port_open(int type, int plen)
+{
+ u_short host_port;
+ char *host, *originator_string;
+ int remote_channel, sock = -1, newch, i, denied;
+ unsigned int host_len, originator_len;
- /* Send a confirmation to the remote host. */
- packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
- packet_put_int(remote_channel);
- packet_put_int(newch);
- packet_send();
+ /* Get remote channel number. */
+ remote_channel = packet_get_int();
- /* Free the argument string. */
- xfree(host);
+ /* Get host name to connect to. */
+ host = packet_get_string(&host_len);
- return;
+ /* Get port to connect to. */
+ host_port = packet_get_int();
-fail:
- /* Free the argument string. */
- xfree(host);
+ /* Get remote originator name. */
+ if (have_hostname_in_open) {
+ originator_string = packet_get_string(&originator_len);
+ originator_len += 4; /* size of packet_int */
+ } else {
+ originator_string = xstrdup("unknown (remote did not supply name)");
+ originator_len = 0; /* no originator supplied */
+ }
- /* Send refusal to the remote host. */
- packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
- packet_put_int(remote_channel);
- packet_send();
+ packet_integrity_check(plen,
+ 4 + 4 + host_len + 4 + originator_len, SSH_MSG_PORT_OPEN);
+
+ /* Check if opening that port is permitted. */
+ denied = 0;
+ if (!all_opens_permitted) {
+ /* Go trough all permitted ports. */
+ for (i = 0; i < num_permitted_opens; i++)
+ if (permitted_opens[i].port_to_connect == host_port &&
+ strcmp(permitted_opens[i].host_to_connect, host) == 0)
+ break;
+
+ /* Check if we found the requested port among those permitted. */
+ if (i >= num_permitted_opens) {
+ /* The port is not permitted. */
+ log("Received request to connect to %.100s:%d, but the request was denied.",
+ host, host_port);
+ denied = 1;
+ }
+ }
+ sock = denied ? -1 : channel_connect_to(host, host_port);
+ if (sock > 0) {
+ /* Allocate a channel for this connection. */
+ newch = channel_allocate(SSH_CHANNEL_OPEN, sock, originator_string);
+ channels[newch].remote_id = remote_channel;
+
+ packet_start(SSH_MSG_CHANNEL_OPEN_CONFIRMATION);
+ packet_put_int(remote_channel);
+ packet_put_int(newch);
+ packet_send();
+ } else {
+ packet_start(SSH_MSG_CHANNEL_OPEN_FAILURE);
+ packet_put_int(remote_channel);
+ packet_send();
+ }
+ xfree(host);
}
/*
*/
void
-x11_input_open(int payload_len)
+x11_input_open(int type, int plen)
{
int remote_channel, display_number, sock = 0, newch;
const char *display;
}
debug("Received X11 open request.");
- packet_integrity_check(payload_len, 4 + remote_len, SSH_SMSG_X11_OPEN);
+ packet_integrity_check(plen, 4 + remote_len, SSH_SMSG_X11_OPEN);
/* Try to open a socket for the local X server. */
display = getenv("DISPLAY");
sock = socket(ai->ai_family, SOCK_STREAM, 0);
if (sock < 0) {
debug("socket: %.100s", strerror(errno));
- continue;
- }
- /* Connect it to the display. */
- if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
- debug("connect %.100s port %d: %.100s", buf, 6000 + display_number,
- strerror(errno));
- close(sock);
- continue;
+ continue;
+ }
+ /* Connect it to the display. */
+ if (connect(sock, ai->ai_addr, ai->ai_addrlen) < 0) {
+ debug("connect %.100s port %d: %.100s", buf,
+ 6000 + display_number, strerror(errno));
+ close(sock);
+ continue;
+ }
+ /* Success */
+ break;
}
- /* Success */
- break;
-
- } /* (ai = aitop, ai; ai = ai->ai_next) */
freeaddrinfo(aitop);
if (!ai) {
error("connect %.100s port %d: %.100s", buf, 6000 + display_number,
/* This is called to process an SSH_SMSG_AGENT_OPEN message. */
void
-auth_input_open_request()
+auth_input_open_request(int type, int plen)
{
int remch, sock, newch;
char *dummyname;
+ packet_integrity_check(plen, 4, type);
+
/* Read the remote channel number from the message. */
remch = packet_get_int();
#define SSH_CHANNEL_OPENING 3 /* waiting for confirmation */
#define SSH_CHANNEL_OPEN 4 /* normal open two-way channel */
#define SSH_CHANNEL_CLOSED 5 /* waiting for close confirmation */
-/* SSH_CHANNEL_AUTH_FD 6 authentication fd */
-#define SSH_CHANNEL_AUTH_SOCKET 7 /* authentication socket */
-/* SSH_CHANNEL_AUTH_SOCKET_FD 8 connection to auth socket */
-#define SSH_CHANNEL_X11_OPEN 9 /* reading first X11 packet */
-#define SSH_CHANNEL_INPUT_DRAINING 10 /* sending remaining data to conn */
-#define SSH_CHANNEL_OUTPUT_DRAINING 11 /* sending remaining data to app */
+#define SSH_CHANNEL_AUTH_SOCKET 6 /* authentication socket */
+#define SSH_CHANNEL_X11_OPEN 7 /* reading first X11 packet */
+#define SSH_CHANNEL_INPUT_DRAINING 8 /* sending remaining data to conn */
+#define SSH_CHANNEL_OUTPUT_DRAINING 9 /* sending remaining data to app */
+#define SSH_CHANNEL_LARVAL 10 /* larval session */
+#define SSH_CHANNEL_MAX_TYPE 11
/*
* Data structure for channel data. This is iniailized in channel_allocate
* and cleared in channel_free.
*/
+typedef void channel_callback_fn(int id, void *arg);
typedef struct Channel {
int type; /* channel type/state */
/* peer can be reached over encrypted connection, via packet-sent */
int istate; /* input from channel (state of receive half) */
int ostate; /* output to channel (state of transmit half) */
- int sock; /* data socket, linked to this channel */
+ int rfd; /* read fd */
+ int wfd; /* write fd */
+ int efd; /* extended fd */
+ int sock; /* sock fd */
Buffer input; /* data read from socket, to be sent over
* encrypted connection */
Buffer output; /* data received over encrypted connection for
* send on socket */
+ Buffer extended;
char path[200]; /* path for unix domain sockets, or host name
* for forwards */
int listening_port; /* port being listened for forwards */
int host_port; /* remote port to connect for forwards */
char *remote_name; /* remote hostname */
+
+ int remote_window;
+ int remote_maxpacket;
+ int local_window;
+ int local_window_max;
+ int local_consumed;
+ int local_maxpacket;
+ int extended_usage;
+
+ char *ctype; /* type */
+
+ // callback
+ channel_callback_fn *cb_fn;
+ void *cb_arg;
+ int cb_event;
+ channel_callback_fn *dettach_user;
} Channel;
+
+#define CHAN_EXTENDED_IGNORE 0
+#define CHAN_EXTENDED_READ 1
+#define CHAN_EXTENDED_WRITE 2
+
+void channel_open(int id);
+Channel *channel_lookup(int id);
+
+int
+channel_new(char *ctype, int type, int rfd, int wfd, int efd,
+ int window, int maxpack, int extended_usage, char *remote_name);
+
+void channel_input_close(int type, int plen);
+void channel_input_close_confirmation(int type, int plen);
+void channel_input_data(int type, int plen);
+void channel_input_ieof(int type, int plen);
+void channel_input_oclose(int type, int plen);
+void channel_input_open_confirmation(int type, int plen);
+void channel_input_open_failure(int type, int plen);
+void channel_input_port_open(int type, int plen);
+void channel_input_open(int type, int plen);
+
+/* Sets specific protocol options. */
+void channel_set_options(int hostname_in_open);
+
+/*
+ * Allocate a new channel object and set its type and socket. Remote_name
+ * must have been allocated with xmalloc; this will free it when the channel
+ * is freed.
+ */
+int channel_allocate(int type, int sock, char *remote_name);
+
+/* Free the channel and close its socket. */
+void channel_free(int channel);
+
+/* Add any bits relevant to channels in select bitmasks. */
+void channel_prepare_select(fd_set * readset, fd_set * writeset);
+
+/*
+ * After select, perform any appropriate operations for channels which have
+ * events pending.
+ */
+void channel_after_select(fd_set * readset, fd_set * writeset);
+
+/* If there is data to send to the connection, send some of it now. */
+void channel_output_poll(void);
+
+/* Returns true if no channel has too much buffered data. */
+int channel_not_very_much_buffered_data(void);
+
+/* This closes any sockets that are listening for connections; this removes
+ any unix domain sockets. */
+void channel_stop_listening(void);
+
+/*
+ * Closes the sockets of all channels. This is used to close extra file
+ * descriptors after a fork.
+ */
+void channel_close_all(void);
+
+/* Returns the maximum file descriptor number used by the channels. */
+int channel_max_fd(void);
+
+/* Returns true if there is still an open channel over the connection. */
+int channel_still_open(void);
+
+/*
+ * Returns a string containing a list of all open channels. The list is
+ * suitable for displaying to the user. It uses crlf instead of newlines.
+ * The caller should free the string with xfree.
+ */
+char *channel_open_message(void);
+
+/*
+ * Initiate forwarding of connections to local port "port" through the secure
+ * channel to host:port from remote side. This never returns if there was an
+ * error.
+ */
+void
+channel_request_local_forwarding(u_short port, const char *host,
+ u_short remote_port, int gateway_ports);
+
+/*
+ * Initiate forwarding of connections to port "port" on remote host through
+ * the secure channel to host:port from local side. This never returns if
+ * there was an error. This registers that open requests for that port are
+ * permitted.
+ */
+void
+channel_request_remote_forwarding(u_short port, const char *host,
+ u_short remote_port);
+
+/*
+ * Permits opening to any host/port in SSH_MSG_PORT_OPEN. This is usually
+ * called by the server, because the user could connect to any port anyway,
+ * and the server has no way to know but to trust the client anyway.
+ */
+void channel_permit_all_opens(void);
+
+/*
+ * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates
+ * listening for the port, and sends back a success reply (or disconnect
+ * message if there was an error). This never returns if there was an error.
+ */
+void channel_input_port_forward_request(int is_root);
+
+/*
+ * Creates a port for X11 connections, and starts listening for it. Returns
+ * the display name, or NULL if an error was encountered.
+ */
+char *x11_create_display(int screen);
+
+/*
+ * Creates an internet domain socket for listening for X11 connections.
+ * Returns a suitable value for the DISPLAY variable, or NULL if an error
+ * occurs.
+ */
+char *x11_create_display_inet(int screen, int x11_display_offset);
+
+/*
+ * This is called when SSH_SMSG_X11_OPEN is received. The packet contains
+ * the remote channel number. We should do whatever we want, and respond
+ * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE.
+ */
+void x11_input_open(int type, int plen);
+
+/*
+ * Requests forwarding of X11 connections. This should be called on the
+ * client only.
+ */
+void x11_request_forwarding(void);
+
+/*
+ * Requests forwarding for X11 connections, with authentication spoofing.
+ * This should be called in the client only.
+ */
+void x11_request_forwarding_with_spoofing(const char *proto, const char *data);
+
+/* Sends a message to the server to request authentication fd forwarding. */
+void auth_request_forwarding(void);
+
+/*
+ * Returns the name of the forwarded authentication socket. Returns NULL if
+ * there is no forwarded authentication socket. The returned value points to
+ * a static buffer.
+ */
+char *auth_get_socket_name(void);
+
+/*
+ * This if called to process SSH_CMSG_AGENT_REQUEST_FORWARDING on the server.
+ * This starts forwarding authentication requests.
+ */
+void auth_input_request_forwarding(struct passwd * pw);
+
+/* This is called to process an SSH_SMSG_AGENT_OPEN message. */
+void auth_input_open_request(int type, int plen);
+
#endif
"3des",
"tss",
"rc4",
- "blowfish"
+ "blowfish",
+ "reserved",
+ "blowfish-cbc",
+ "3des-cbc",
+ "arcfour",
+ "cast128-cbc"
};
/*
unsigned int mask = 0;
mask |= 1 << SSH_CIPHER_3DES; /* Mandatory */
mask |= 1 << SSH_CIPHER_BLOWFISH;
+ mask |= 1 << SSH_CIPHER_BLOWFISH_CBC;
+ mask |= 1 << SSH_CIPHER_3DES_CBC;
+ mask |= 1 << SSH_CIPHER_ARCFOUR;
+ mask |= 1 << SSH_CIPHER_CAST128_CBC;
return mask;
}
break;
case SSH_CIPHER_BLOWFISH:
+ if (keylen < 16)
+ error("Key length %d is insufficient for blowfish.", keylen);
BF_set_key(&context->u.bf.key, keylen, padded);
memset(context->u.bf.iv, 0, 8);
break;
+ case SSH_CIPHER_3DES_CBC:
+ case SSH_CIPHER_BLOWFISH_CBC:
+ case SSH_CIPHER_ARCFOUR:
+ case SSH_CIPHER_CAST128_CBC:
+ fatal("cipher_set_key: illegal cipher: %s", cipher_name(cipher));
+ break;
+
default:
fatal("cipher_set_key: unknown cipher: %s", cipher_name(cipher));
}
memset(padded, 0, sizeof(padded));
}
+
+void
+cipher_set_key_iv(CipherContext * context, int cipher,
+ const unsigned char *key, int keylen,
+ const unsigned char *iv, int ivlen)
+{
+ /* Set cipher type. */
+ context->type = cipher;
+
+ /* Initialize the initialization vector. */
+ switch (cipher) {
+ case SSH_CIPHER_NONE:
+ break;
+
+ case SSH_CIPHER_3DES:
+ case SSH_CIPHER_BLOWFISH:
+ fatal("cipher_set_key_iv: illegal cipher: %s", cipher_name(cipher));
+ break;
+
+ case SSH_CIPHER_3DES_CBC:
+ if (keylen < 24)
+ error("Key length %d is insufficient for 3des-cbc.", keylen);
+ des_set_key((void *) key, context->u.des3.key1);
+ des_set_key((void *) (key+8), context->u.des3.key2);
+ des_set_key((void *) (key+16), context->u.des3.key3);
+ if (ivlen < 8)
+ error("IV length %d is insufficient for 3des-cbc.", ivlen);
+ memcpy(context->u.des3.iv3, (char *)iv, 8);
+ break;
+
+ case SSH_CIPHER_BLOWFISH_CBC:
+ if (keylen < 16)
+ error("Key length %d is insufficient for blowfish.", keylen);
+ if (ivlen < 8)
+ error("IV length %d is insufficient for blowfish.", ivlen);
+ BF_set_key(&context->u.bf.key, keylen, (unsigned char *)key);
+ memcpy(context->u.bf.iv, (char *)iv, 8);
+ break;
+
+ case SSH_CIPHER_ARCFOUR:
+ if (keylen < 16)
+ error("Key length %d is insufficient for arcfour.", keylen);
+ RC4_set_key(&context->u.rc4, keylen, (unsigned char *)key);
+ break;
+
+ case SSH_CIPHER_CAST128_CBC:
+ if (keylen < 16)
+ error("Key length %d is insufficient for cast128.", keylen);
+ if (ivlen < 8)
+ error("IV length %d is insufficient for cast128.", ivlen);
+ CAST_set_key(&context->u.cast.key, keylen, (unsigned char *) key);
+ memcpy(context->u.cast.iv, (char *)iv, 8);
+ break;
+
+ default:
+ fatal("cipher_set_key: unknown cipher: %s", cipher_name(cipher));
+ }
+}
+
/* Encrypts data using the cipher. */
void
swap_bytes(dest, dest, len);
break;
+ case SSH_CIPHER_BLOWFISH_CBC:
+ BF_cbc_encrypt((void *)src, dest, len,
+ &context->u.bf.key, context->u.bf.iv,
+ BF_ENCRYPT);
+ break;
+
+ case SSH_CIPHER_3DES_CBC:
+ des_ede3_cbc_encrypt(src, dest, len,
+ context->u.des3.key1, context->u.des3.key2,
+ context->u.des3.key3, &context->u.des3.iv3, DES_ENCRYPT);
+ break;
+
+ case SSH_CIPHER_ARCFOUR:
+ RC4(&context->u.rc4, len, (unsigned char *)src, dest);
+ break;
+
+ case SSH_CIPHER_CAST128_CBC:
+ CAST_cbc_encrypt(src, dest, len,
+ &context->u.cast.key, context->u.cast.iv, CAST_ENCRYPT);
+ break;
+
default:
fatal("cipher_encrypt: unknown cipher: %s", cipher_name(context->type));
}
swap_bytes(dest, dest, len);
break;
+ case SSH_CIPHER_BLOWFISH_CBC:
+ BF_cbc_encrypt((void *) src, dest, len,
+ &context->u.bf.key, context->u.bf.iv,
+ BF_DECRYPT);
+ break;
+
+ case SSH_CIPHER_3DES_CBC:
+ des_ede3_cbc_encrypt(src, dest, len,
+ context->u.des3.key1, context->u.des3.key2,
+ context->u.des3.key3, &context->u.des3.iv3, DES_DECRYPT);
+ break;
+
+ case SSH_CIPHER_ARCFOUR:
+ RC4(&context->u.rc4, len, (unsigned char *)src, dest);
+ break;
+
+ case SSH_CIPHER_CAST128_CBC:
+ CAST_cbc_encrypt(src, dest, len,
+ &context->u.cast.key, context->u.cast.iv, CAST_DECRYPT);
+ break;
+
default:
fatal("cipher_decrypt: unknown cipher: %s", cipher_name(context->type));
}
#ifdef HAVE_OPENSSL
#include <openssl/des.h>
#include <openssl/blowfish.h>
+#include <openssl/rc4.h>
+#include <openssl/cast.h>
#endif
#ifdef HAVE_SSL
#include <ssl/des.h>
#include <ssl/blowfish.h>
+#include <ssl/rc4.h>
+#include <ssl/cast.h>
#endif
/* Cipher types. New types can be added, but old types should not be removed
#define SSH_CIPHER_BROKEN_TSS 4 /* TRI's Simple Stream encryption CBC */
#define SSH_CIPHER_BROKEN_RC4 5 /* Alleged RC4 */
#define SSH_CIPHER_BLOWFISH 6
+#define SSH_CIPHER_RESERVED 7
+
+/* these ciphers are used in SSH2: */
+#define SSH_CIPHER_BLOWFISH_CBC 8
+#define SSH_CIPHER_3DES_CBC 9
+#define SSH_CIPHER_ARCFOUR 10 /* Alleged RC4 */
+#define SSH_CIPHER_CAST128_CBC 11
typedef struct {
unsigned int type;
struct bf_key_st key;
unsigned char iv[8];
} bf;
+ struct {
+ CAST_KEY key;
+ unsigned char iv[8];
+ } cast;
+ RC4_KEY rc4;
} u;
} CipherContext;
/*
void
cipher_set_key(CipherContext * context, int cipher,
const unsigned char *key, int keylen, int for_encryption);
+void
+cipher_set_key_iv(CipherContext * context, int cipher,
+ const unsigned char *key, int keylen,
+ const unsigned char *iv, int ivlen);
/*
* Sets key for the cipher by computing the MD5 checksum of the passphrase,
#include "authfd.h"
#include "readconf.h"
+#include "compat.h"
+#include "channels.h"
+#include "dispatch.h"
+
+
/* Flag indicating that stdin should be redirected from /dev/null. */
extern int stdin_null_flag;
}
}
-/*
- * Get packets from the connection input buffer, and process them as long as
- * there are packets available.
- */
-
-void
-client_process_buffered_input_packets()
-{
- int type;
- char *data;
- unsigned int data_len;
- int payload_len;
-
- /* Process any buffered packets from the server. */
- while (!quit_pending &&
- (type = packet_read_poll(&payload_len)) != SSH_MSG_NONE) {
- switch (type) {
-
- case SSH_SMSG_STDOUT_DATA:
- data = packet_get_string(&data_len);
- packet_integrity_check(payload_len, 4 + data_len, type);
- buffer_append(&stdout_buffer, data, data_len);
- stdout_bytes += data_len;
- memset(data, 0, data_len);
- xfree(data);
- break;
-
- case SSH_SMSG_STDERR_DATA:
- data = packet_get_string(&data_len);
- packet_integrity_check(payload_len, 4 + data_len, type);
- buffer_append(&stderr_buffer, data, data_len);
- stdout_bytes += data_len;
- memset(data, 0, data_len);
- xfree(data);
- break;
-
- case SSH_SMSG_EXITSTATUS:
- packet_integrity_check(payload_len, 4, type);
- exit_status = packet_get_int();
- /* Acknowledge the exit. */
- packet_start(SSH_CMSG_EXIT_CONFIRMATION);
- packet_send();
- /*
- * Must wait for packet to be sent since we are
- * exiting the loop.
- */
- packet_write_wait();
- /* Flag that we want to exit. */
- quit_pending = 1;
- break;
-
- case SSH_SMSG_X11_OPEN:
- x11_input_open(payload_len);
- break;
-
- case SSH_MSG_PORT_OPEN:
- channel_input_port_open(payload_len);
- break;
-
- case SSH_SMSG_AGENT_OPEN:
- packet_integrity_check(payload_len, 4, type);
- auth_input_open_request();
- break;
-
- case SSH_MSG_CHANNEL_OPEN_CONFIRMATION:
- packet_integrity_check(payload_len, 4 + 4, type);
- channel_input_open_confirmation();
- break;
-
- case SSH_MSG_CHANNEL_OPEN_FAILURE:
- packet_integrity_check(payload_len, 4, type);
- channel_input_open_failure();
- break;
-
- case SSH_MSG_CHANNEL_DATA:
- channel_input_data(payload_len);
- break;
-
- case SSH_MSG_CHANNEL_CLOSE:
- packet_integrity_check(payload_len, 4, type);
- channel_input_close();
- break;
-
- case SSH_MSG_CHANNEL_CLOSE_CONFIRMATION:
- packet_integrity_check(payload_len, 4, type);
- channel_input_close_confirmation();
- break;
-
- default:
- /*
- * Any unknown packets received during the actual
- * session cause the session to terminate. This is
- * intended to make debugging easier since no
- * confirmations are sent. Any compatible protocol
- * extensions must be negotiated during the
- * preparatory phase.
- */
- packet_disconnect("Protocol error during session: type %d",
- type);
- }
- }
-}
/*
* Make packets from buffered stdin data, and buffer them for sending to the
}
}
+/*
+ * Get packets from the connection input buffer, and process them as long as
+ * there are packets available.
+ *
+ * Any unknown packets received during the actual
+ * session cause the session to terminate. This is
+ * intended to make debugging easier since no
+ * confirmations are sent. Any compatible protocol
+ * extensions must be negotiated during the
+ * preparatory phase.
+ */
+
+void
+client_process_buffered_input_packets()
+{
+ dispatch_run(DISPATCH_NONBLOCK, &quit_pending);
+}
+
/*
* Implements the interactive session with the server. This is called after
* the user has been authenticated, and a command has been started on the
* character for terminating or suspending the session.
*/
+void client_init_dispatch(void);
+
int
client_loop(int have_pty, int escape_char_arg)
{
buffer_init(&stdout_buffer);
buffer_init(&stderr_buffer);
+ client_init_dispatch();
+
/* Set signal handlers to restore non-blocking mode. */
signal(SIGINT, signal_handler);
signal(SIGQUIT, signal_handler);
debug("Exit status %d", exit_status);
return exit_status;
}
+
+/*********/
+
+void
+client_input_stdout_data(int type, int plen)
+{
+ unsigned int data_len;
+ char *data = packet_get_string(&data_len);
+ packet_integrity_check(plen, 4 + data_len, type);
+ buffer_append(&stdout_buffer, data, data_len);
+ stdout_bytes += data_len;
+ memset(data, 0, data_len);
+ xfree(data);
+}
+void
+client_input_stderr_data(int type, int plen)
+{
+ unsigned int data_len;
+ char *data = packet_get_string(&data_len);
+ packet_integrity_check(plen, 4 + data_len, type);
+ buffer_append(&stderr_buffer, data, data_len);
+ stdout_bytes += data_len;
+ memset(data, 0, data_len);
+ xfree(data);
+}
+void
+client_input_exit_status(int type, int plen)
+{
+ packet_integrity_check(plen, 4, type);
+ exit_status = packet_get_int();
+ /* Acknowledge the exit. */
+ packet_start(SSH_CMSG_EXIT_CONFIRMATION);
+ packet_send();
+ /*
+ * Must wait for packet to be sent since we are
+ * exiting the loop.
+ */
+ packet_write_wait();
+ /* Flag that we want to exit. */
+ quit_pending = 1;
+}
+
+void
+client_init_dispatch_13()
+{
+ dispatch_init(NULL);
+ dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close);
+ dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation);
+ dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data);
+ dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data);
+ dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
+ dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
+ dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open);
+ dispatch_set(SSH_SMSG_AGENT_OPEN, &auth_input_open_request);
+ dispatch_set(SSH_SMSG_EXITSTATUS, &client_input_exit_status);
+ dispatch_set(SSH_SMSG_STDERR_DATA, &client_input_stderr_data);
+ dispatch_set(SSH_SMSG_STDOUT_DATA, &client_input_stdout_data);
+ dispatch_set(SSH_SMSG_X11_OPEN, &x11_input_open);
+}
+void
+client_init_dispatch_15()
+{
+ client_init_dispatch_13();
+ dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof);
+ dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, & channel_input_oclose);
+}
+void
+client_init_dispatch()
+{
+ if (compat13)
+ client_init_dispatch_13();
+ else
+ client_init_dispatch_15();
+}
case Z_OK:
/* Append compressed data to output_buffer. */
buffer_append(output_buffer, buf,
- sizeof(buf) - outgoing_stream.avail_out);
+ sizeof(buf) - outgoing_stream.avail_out);
break;
- case Z_STREAM_END:
- fatal("buffer_compress: deflate returned Z_STREAM_END");
- /* NOTREACHED */
- case Z_STREAM_ERROR:
- fatal("buffer_compress: deflate returned Z_STREAM_ERROR");
- /* NOTREACHED */
- case Z_BUF_ERROR:
- fatal("buffer_compress: deflate returned Z_BUF_ERROR");
- /* NOTREACHED */
default:
fatal("buffer_compress: deflate returned %d", status);
/* NOTREACHED */
}
- }
- while (outgoing_stream.avail_out == 0);
+ } while (outgoing_stream.avail_out == 0);
}
/*
incoming_stream.next_in = (unsigned char *) buffer_ptr(input_buffer);
incoming_stream.avail_in = buffer_len(input_buffer);
- incoming_stream.next_out = (unsigned char *) buf;
- incoming_stream.avail_out = sizeof(buf);
-
for (;;) {
+ /* Set up fixed-size output buffer. */
+ incoming_stream.next_out = (unsigned char *) buf;
+ incoming_stream.avail_out = sizeof(buf);
+
status = inflate(&incoming_stream, Z_PARTIAL_FLUSH);
switch (status) {
case Z_OK:
buffer_append(output_buffer, buf,
- sizeof(buf) - incoming_stream.avail_out);
- incoming_stream.next_out = (unsigned char *) buf;
- incoming_stream.avail_out = sizeof(buf);
+ sizeof(buf) - incoming_stream.avail_out);
break;
- case Z_STREAM_END:
- fatal("buffer_uncompress: inflate returned Z_STREAM_END");
- /* NOTREACHED */
- case Z_DATA_ERROR:
- fatal("buffer_uncompress: inflate returned Z_DATA_ERROR");
- /* NOTREACHED */
- case Z_STREAM_ERROR:
- fatal("buffer_uncompress: inflate returned Z_STREAM_ERROR");
- /* NOTREACHED */
case Z_BUF_ERROR:
/*
* Comments in zlib.h say that we should keep calling
* be the error that we get.
*/
return;
- case Z_MEM_ERROR:
- fatal("buffer_uncompress: inflate returned Z_MEM_ERROR");
- /* NOTREACHED */
default:
fatal("buffer_uncompress: inflate returned %d", status);
+ /* NOTREACHED */
}
}
}
--- /dev/null
+/*
+ * Copyright (c) 2000 Markus Friedl. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ * notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ * notice, this list of conditions and the following disclaimer in the
+ * documentation and/or other materials provided with the distribution.
+ * 3. All advertising materials mentioning features or use of this software
+ * must display the following acknowledgement:
+ * This product includes software developed by Markus Friedl.
+ * 4. The name of the author may not be used to endorse or promote products
+ * derived from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
+ * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
+ * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
+ * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
+ * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
+ * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+#include "includes.h"
+RCSID("$Id$");
+#include "ssh.h"
+#include "dispatch.h"
+#include "packet.h"
+
+#define DISPATCH_MIN 0
+#define DISPATCH_MAX 255
+
+dispatch_fn *dispatch[DISPATCH_MAX];
+
+void
+dispatch_protocol_error(int type, int plen)
+{
+ error("Hm, dispatch protocol error: type %d plen %d", type, plen);
+}
+void
+dispatch_init(dispatch_fn *dflt)
+{
+ int i;
+ for (i = 0; i < DISPATCH_MAX; i++)
+ dispatch[i] = dflt;
+}
+void
+dispatch_set(int type, dispatch_fn *fn)
+{
+ dispatch[type] = fn;
+}
+void
+dispatch_run(int mode, int *done)
+{
+ for (;;) {
+ int plen;
+ int type;
+
+ if (mode == DISPATCH_BLOCK) {
+ type = packet_read(&plen);
+ } else {
+ type = packet_read_poll(&plen);
+ if (type == SSH_MSG_NONE)
+ return;
+ }
+ if (type > 0 && type < DISPATCH_MAX && dispatch[type] != NULL)
+ (*dispatch[type])(type, plen);
+ else
+ packet_disconnect("protocol error: rcvd type %d", type);
+ if (done != NULL && *done)
+ return;
+ }
+}
--- /dev/null
+enum {
+ DISPATCH_BLOCK,
+ DISPATCH_NONBLOCK
+};
+
+typedef void dispatch_fn(int type, int plen);
+
+void dispatch_init(dispatch_fn *dflt);
+void dispatch_set(int type, dispatch_fn *fn);
+void dispatch_run(int mode, int *done);
+void dispatch_protocol_error(int type, int plen);
} else {
vsnprintf(msgbuf, sizeof(msgbuf), fmt, args);
}
- if (log_on_stderr)
+ if (log_on_stderr) {
fprintf(stderr, "%s\n", msgbuf);
- openlog(__progname, LOG_PID, log_facility);
- syslog(pri, "%.500s", msgbuf);
- closelog();
+ } else {
+ openlog(__progname, LOG_PID, log_facility);
+ syslog(pri, "%.500s", msgbuf);
+ closelog();
+ }
}
void
compute_session_id(unsigned char session_id[16],
- unsigned char cookie[8],
- BIGNUM* host_key_n,
- BIGNUM* session_key_n)
+ unsigned char cookie[8],
+ BIGNUM* host_key_n,
+ BIGNUM* session_key_n)
{
unsigned int host_key_bytes = BN_num_bytes(host_key_n);
unsigned int session_key_bytes = BN_num_bytes(session_key_n);
static void chan_send_oclose(Channel *c);
static void chan_shutdown_write(Channel *c);
static void chan_shutdown_read(Channel *c);
-static void chan_delete_if_full_closed(Channel *c);
/*
* EVENTS update channel input/output states execute ACTIONS
error("protocol error: chan_rcvd_oclose %d for istate %d", c->self, c->istate);
return;
}
- chan_delete_if_full_closed(c);
}
void
chan_read_failed(Channel *c)
case CHAN_OUTPUT_WAIT_IEOF:
debug("channel %d: OUTPUT_WAIT_IEOF -> OUTPUT_CLOSED [rvcd IEOF]", c->self);
c->ostate = CHAN_OUTPUT_CLOSED;
- chan_delete_if_full_closed(c);
break;
default:
error("protocol error: chan_rcvd_ieof %d for ostate %d", c->self, c->ostate);
debug("channel %d: OUTPUT_WAIT_DRAIN -> OUTPUT_CLOSED [write failed]", c->self);
chan_send_oclose(c);
c->ostate = CHAN_OUTPUT_CLOSED;
- chan_delete_if_full_closed(c);
break;
default:
error("internal error: chan_write_failed %d for ostate %d", c->self, c->ostate);
debug("channel %d: OUTPUT_WAIT_DRAIN -> OUTPUT_CLOSED [obuf empty, send OCLOSE]", c->self);
chan_send_oclose(c);
c->ostate = CHAN_OUTPUT_CLOSED;
- chan_delete_if_full_closed(c);
break;
default:
error("internal error: chan_obuf_empty %d for ostate %d", c->self, c->ostate);
error("chan_shutdown_read failed for #%d/fd%d [i%d o%d]: %.100s",
c->self, c->sock, c->istate, c->ostate, strerror(errno));
}
-static void
+void
chan_delete_if_full_closed(Channel *c)
{
if (c->istate == CHAN_INPUT_CLOSED && c->ostate == CHAN_OUTPUT_CLOSED) {
void chan_obuf_empty(Channel * c);
void chan_init_iostates(Channel * c);
+
+void chan_delete_if_full_closed(Channel *c);
#endif
#include "compress.h"
#include "deattack.h"
+#include "channels.h"
/*
* This variable contains the file descriptors used for communicating with
void pty_setowner(struct passwd *pw, const char *ttyname);
-void pty_setowner(struct passwd *pw, const char *ttyname);
-
#endif /* PTY_H */
#include "ssh.h"
#include "cipher.h"
#include "readconf.h"
+#include "match.h"
#include "xmalloc.h"
/* Format of the configuration file:
#include "buffer.h"
#include "servconf.h"
#include "pty.h"
+#include "channels.h"
+
+#include "compat.h"
+#include "dispatch.h"
static Buffer stdin_buffer; /* Buffer for stdin data. */
static Buffer stdout_buffer; /* Buffer for stdout data. */
static volatile int child_has_selected; /* Child has had chance to drain. */
static volatile int child_wait_status; /* Status from wait(). */
+void server_init_dispatch(void);
+
void
sigchld_handler(int sig)
{
errno = save_errno;
}
-/*
- * Process any buffered packets that have been received from the client.
- */
-void
-process_buffered_input_packets()
-{
- int type;
- char *data;
- unsigned int data_len;
- int row, col, xpixel, ypixel;
- int payload_len;
-
- /* Process buffered packets from the client. */
- while ((type = packet_read_poll(&payload_len)) != SSH_MSG_NONE) {
- switch (type) {
- case SSH_CMSG_STDIN_DATA:
- /* Stdin data from the client. Append it to the buffer. */
- /* Ignore any data if the client has closed stdin. */
- if (fdin == -1)
- break;
- data = packet_get_string(&data_len);
- packet_integrity_check(payload_len, (4 + data_len), type);
- buffer_append(&stdin_buffer, data, data_len);
- memset(data, 0, data_len);
- xfree(data);
- break;
-
- case SSH_CMSG_EOF:
- /*
- * Eof from the client. The stdin descriptor to the
- * program will be closed when all buffered data has
- * drained.
- */
- debug("EOF received for stdin.");
- packet_integrity_check(payload_len, 0, type);
- stdin_eof = 1;
- break;
-
- case SSH_CMSG_WINDOW_SIZE:
- debug("Window change received.");
- packet_integrity_check(payload_len, 4 * 4, type);
- row = packet_get_int();
- col = packet_get_int();
- xpixel = packet_get_int();
- ypixel = packet_get_int();
- if (fdin != -1)
- pty_change_window_size(fdin, row, col, xpixel, ypixel);
- break;
-
- case SSH_MSG_PORT_OPEN:
- debug("Received port open request.");
- channel_input_port_open(payload_len);
- break;
-
- case SSH_MSG_CHANNEL_OPEN_CONFIRMATION:
- debug("Received channel open confirmation.");
- packet_integrity_check(payload_len, 4 + 4, type);
- channel_input_open_confirmation();
- break;
-
- case SSH_MSG_CHANNEL_OPEN_FAILURE:
- debug("Received channel open failure.");
- packet_integrity_check(payload_len, 4, type);
- channel_input_open_failure();
- break;
-
- case SSH_MSG_CHANNEL_DATA:
- channel_input_data(payload_len);
- break;
-
- case SSH_MSG_CHANNEL_CLOSE:
- debug("Received channel close.");
- packet_integrity_check(payload_len, 4, type);
- channel_input_close();
- break;
-
- case SSH_MSG_CHANNEL_CLOSE_CONFIRMATION:
- debug("Received channel close confirmation.");
- packet_integrity_check(payload_len, 4, type);
- channel_input_close_confirmation();
- break;
-
- default:
- /*
- * In this phase, any unexpected messages cause a
- * protocol error. This is to ease debugging; also,
- * since no confirmations are sent messages,
- * unprocessed unknown messages could cause strange
- * problems. Any compatible protocol extensions must
- * be negotiated before entering the interactive
- * session.
- */
- packet_disconnect("Protocol error during session: type %d",
- type);
- }
- }
-}
-
/*
* Make packets from buffered stderr data, and buffer it for sending
* to the client.
#ifdef USE_PIPES
close(fdin);
#else
- if (fdout == -1)
+ if (fdin != fdout)
close(fdin);
else
shutdown(fdin, SHUT_WR); /* We will no longer send. */
packet_write_wait();
}
+void
+process_buffered_input_packets()
+{
+ dispatch_run(DISPATCH_NONBLOCK, NULL);
+}
+
/*
* Performs the interactive session. This handles data transmission between
* the client and the program. Note that the notion of stdin, stdout, and
if (fderr == -1)
fderr_eof = 1;
+ server_init_dispatch();
+
/* Main loop of the server for the interactive session mode. */
for (;;) {
fd_set readset, writeset;
#ifdef USE_PIPES
close(fdin);
#else
- if (fdout == -1)
+ if (fdin != fdout)
close(fdin);
else
shutdown(fdin, SHUT_WR); /* We will no longer send. */
(buffer_len(&stdout_buffer) == 0) &&
(buffer_len(&stderr_buffer) == 0)) {
if (!channel_still_open())
- goto quit;
+ break;
if (!waiting_termination) {
const char *s = "Waiting for forwarded connections to terminate...\r\n";
char *cp;
process_output(&writeset);
}
-quit:
/* Cleanup and termination code. */
/* Wait until all output has been sent to the client. */
packet_disconnect("wait returned status %04x.", wait_status);
/* NOTREACHED */
}
+
+void
+server_input_stdin_data(int type, int plen)
+{
+ char *data;
+ unsigned int data_len;
+
+ /* Stdin data from the client. Append it to the buffer. */
+ /* Ignore any data if the client has closed stdin. */
+ if (fdin == -1)
+ return;
+ data = packet_get_string(&data_len);
+ packet_integrity_check(plen, (4 + data_len), type);
+ buffer_append(&stdin_buffer, data, data_len);
+ memset(data, 0, data_len);
+ xfree(data);
+}
+
+void
+server_input_eof(int type, int plen)
+{
+ /*
+ * Eof from the client. The stdin descriptor to the
+ * program will be closed when all buffered data has
+ * drained.
+ */
+ debug("EOF received for stdin.");
+ packet_integrity_check(plen, 0, type);
+ stdin_eof = 1;
+}
+
+void
+server_input_window_size(int type, int plen)
+{
+ int row = packet_get_int();
+ int col = packet_get_int();
+ int xpixel = packet_get_int();
+ int ypixel = packet_get_int();
+
+ debug("Window change received.");
+ packet_integrity_check(plen, 4 * 4, type);
+ if (fdin != -1)
+ pty_change_window_size(fdin, row, col, xpixel, ypixel);
+}
+
+void
+server_init_dispatch_13()
+{
+ debug("server_init_dispatch_13");
+ dispatch_init(NULL);
+ dispatch_set(SSH_CMSG_EOF, &server_input_eof);
+ dispatch_set(SSH_CMSG_STDIN_DATA, &server_input_stdin_data);
+ dispatch_set(SSH_CMSG_WINDOW_SIZE, &server_input_window_size);
+ dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_close);
+ dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_close_confirmation);
+ dispatch_set(SSH_MSG_CHANNEL_DATA, &channel_input_data);
+ dispatch_set(SSH_MSG_CHANNEL_OPEN_CONFIRMATION, &channel_input_open_confirmation);
+ dispatch_set(SSH_MSG_CHANNEL_OPEN_FAILURE, &channel_input_open_failure);
+ dispatch_set(SSH_MSG_PORT_OPEN, &channel_input_port_open);
+}
+void
+server_init_dispatch_15()
+{
+ server_init_dispatch_13();
+ debug("server_init_dispatch_15");
+ dispatch_set(SSH_MSG_CHANNEL_CLOSE, &channel_input_ieof);
+ dispatch_set(SSH_MSG_CHANNEL_CLOSE_CONFIRMATION, &channel_input_oclose);
+}
+void
+server_init_dispatch()
+{
+ if (compat13)
+ server_init_dispatch_13();
+ else
+ server_init_dispatch_15();
+}
--- /dev/null
+/*
+ * Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
+ * All rights reserved
+ */
+
+#include "includes.h"
+RCSID("$OpenBSD: session.c,v 1.1 2000/03/28 21:15:45 markus Exp $");
+
+#include "xmalloc.h"
+#include "ssh.h"
+#include "pty.h"
+#include "packet.h"
+#include "buffer.h"
+#include "cipher.h"
+#include "mpaux.h"
+#include "servconf.h"
+#include "uidswap.h"
+#include "compat.h"
+#include "channels.h"
+#include "nchan.h"
+
+/* types */
+
+#define TTYSZ 64
+typedef struct Session Session;
+struct Session {
+ int used;
+ int self;
+ struct passwd *pw;
+ pid_t pid;
+ /* tty */
+ char *term;
+ int ptyfd, ttyfd, ptymaster;
+ int row, col, xpixel, ypixel;
+ char tty[TTYSZ];
+ /* X11 */
+ char *display;
+ int screen;
+ char *auth_proto;
+ char *auth_data;
+ /* proto 2 */
+ int chanid;
+};
+
+/* func */
+
+Session *session_new(void);
+void session_set_fds(Session *s, int fdin, int fdout, int fderr);
+void session_pty_cleanup(Session *s);
+void do_exec_pty(Session *s, const char *command, struct passwd * pw);
+void do_exec_no_pty(Session *s, const char *command, struct passwd * pw);
+
+void
+do_child(const char *command, struct passwd * pw, const char *term,
+ const char *display, const char *auth_proto,
+ const char *auth_data, const char *ttyname);
+
+/* import */
+extern ServerOptions options;
+extern char *__progname;
+extern int log_stderr;
+extern int debug_flag;
+
+/* Local Xauthority file. */
+static char *xauthfile;
+
+/* data */
+#define MAX_SESSIONS 10
+Session sessions[MAX_SESSIONS];
+
+/* Flags set in auth-rsa from authorized_keys flags. These are set in auth-rsa.c. */
+int no_port_forwarding_flag = 0;
+int no_agent_forwarding_flag = 0;
+int no_x11_forwarding_flag = 0;
+int no_pty_flag = 0;
+
+/* RSA authentication "command=" option. */
+char *forced_command = NULL;
+
+/* RSA authentication "environment=" options. */
+struct envstring *custom_environment = NULL;
+
+/*
+ * Remove local Xauthority file.
+ */
+void
+xauthfile_cleanup_proc(void *ignore)
+{
+ debug("xauthfile_cleanup_proc called");
+
+ if (xauthfile != NULL) {
+ char *p;
+ unlink(xauthfile);
+ p = strrchr(xauthfile, '/');
+ if (p != NULL) {
+ *p = '\0';
+ rmdir(xauthfile);
+ }
+ xfree(xauthfile);
+ xauthfile = NULL;
+ }
+}
+
+/*
+ * Function to perform cleanup if we get aborted abnormally (e.g., due to a
+ * dropped connection).
+ */
+void
+pty_cleanup_proc(void *session)
+{
+ Session *s=session;
+ if (s == NULL)
+ fatal("pty_cleanup_proc: no session");
+ debug("pty_cleanup_proc: %s", s->tty);
+
+ if (s->pid != 0) {
+ /* Record that the user has logged out. */
+ record_logout(s->pid, s->tty);
+ }
+
+ /* Release the pseudo-tty. */
+ pty_release(s->tty);
+}
+
+/*
+ * Prepares for an interactive session. This is called after the user has
+ * been successfully authenticated. During this message exchange, pseudo
+ * terminals are allocated, X11, TCP/IP, and authentication agent forwardings
+ * are requested, etc.
+ */
+void
+do_authenticated(struct passwd * pw)
+{
+ Session *s;
+ int type;
+ int compression_level = 0, enable_compression_after_reply = 0;
+ int have_pty = 0;
+ char *command;
+ int n_bytes;
+ int plen;
+ unsigned int proto_len, data_len, dlen;
+
+ /*
+ * Cancel the alarm we set to limit the time taken for
+ * authentication.
+ */
+ alarm(0);
+
+ /*
+ * Inform the channel mechanism that we are the server side and that
+ * the client may request to connect to any port at all. (The user
+ * could do it anyway, and we wouldn\'t know what is permitted except
+ * by the client telling us, so we can equally well trust the client
+ * not to request anything bogus.)
+ */
+ if (!no_port_forwarding_flag)
+ channel_permit_all_opens();
+
+ s = session_new();
+
+ /*
+ * We stay in this loop until the client requests to execute a shell
+ * or a command.
+ */
+ for (;;) {
+ int success = 0;
+
+ /* Get a packet from the client. */
+ type = packet_read(&plen);
+
+ /* Process the packet. */
+ switch (type) {
+ case SSH_CMSG_REQUEST_COMPRESSION:
+ packet_integrity_check(plen, 4, type);
+ compression_level = packet_get_int();
+ if (compression_level < 1 || compression_level > 9) {
+ packet_send_debug("Received illegal compression level %d.",
+ compression_level);
+ break;
+ }
+ /* Enable compression after we have responded with SUCCESS. */
+ enable_compression_after_reply = 1;
+ success = 1;
+ break;
+
+ case SSH_CMSG_REQUEST_PTY:
+ if (no_pty_flag) {
+ debug("Allocating a pty not permitted for this authentication.");
+ break;
+ }
+ if (have_pty)
+ packet_disconnect("Protocol error: you already have a pty.");
+
+ debug("Allocating pty.");
+
+ /* Allocate a pty and open it. */
+ if (!pty_allocate(&s->ptyfd, &s->ttyfd, s->tty,
+ sizeof(s->tty))) {
+ error("Failed to allocate pty.");
+ break;
+ }
+ fatal_add_cleanup(pty_cleanup_proc, (void *)s);
+ pty_setowner(pw, s->tty);
+
+ /* Get TERM from the packet. Note that the value may be of arbitrary length. */
+ s->term = packet_get_string(&dlen);
+ packet_integrity_check(dlen, strlen(s->term), type);
+ /* packet_integrity_check(plen, 4 + dlen + 4*4 + n_bytes, type); */
+ /* Remaining bytes */
+ n_bytes = plen - (4 + dlen + 4 * 4);
+
+ if (strcmp(s->term, "") == 0) {
+ xfree(s->term);
+ s->term = NULL;
+ }
+ /* Get window size from the packet. */
+ s->row = packet_get_int();
+ s->col = packet_get_int();
+ s->xpixel = packet_get_int();
+ s->ypixel = packet_get_int();
+ pty_change_window_size(s->ptyfd, s->row, s->col, s->xpixel, s->ypixel);
+
+ /* Get tty modes from the packet. */
+ tty_parse_modes(s->ttyfd, &n_bytes);
+ packet_integrity_check(plen, 4 + dlen + 4 * 4 + n_bytes, type);
+
+ /* Indicate that we now have a pty. */
+ success = 1;
+ have_pty = 1;
+ break;
+
+ case SSH_CMSG_X11_REQUEST_FORWARDING:
+ if (!options.x11_forwarding) {
+ packet_send_debug("X11 forwarding disabled in server configuration file.");
+ break;
+ }
+#ifdef XAUTH_PATH
+ if (no_x11_forwarding_flag) {
+ packet_send_debug("X11 forwarding not permitted for this authentication.");
+ break;
+ }
+ debug("Received request for X11 forwarding with auth spoofing.");
+ if (s->display != NULL)
+ packet_disconnect("Protocol error: X11 display already set.");
+
+ s->auth_proto = packet_get_string(&proto_len);
+ s->auth_data = packet_get_string(&data_len);
+ packet_integrity_check(plen, 4 + proto_len + 4 + data_len + 4, type);
+
+ if (packet_get_protocol_flags() & SSH_PROTOFLAG_SCREEN_NUMBER)
+ s->screen = packet_get_int();
+ else
+ s->screen = 0;
+ s->display = x11_create_display_inet(s->screen, options.x11_display_offset);
+
+ if (s->display == NULL)
+ break;
+
+ /* Setup to always have a local .Xauthority. */
+ xauthfile = xmalloc(MAXPATHLEN);
+ strlcpy(xauthfile, "/tmp/ssh-XXXXXXXX", MAXPATHLEN);
+ temporarily_use_uid(pw->pw_uid);
+ if (mkdtemp(xauthfile) == NULL) {
+ restore_uid();
+ error("private X11 dir: mkdtemp %s failed: %s",
+ xauthfile, strerror(errno));
+ xfree(xauthfile);
+ xauthfile = NULL;
+ break;
+ }
+ strlcat(xauthfile, "/cookies", MAXPATHLEN);
+ open(xauthfile, O_RDWR|O_CREAT|O_EXCL, 0600);
+ restore_uid();
+ fatal_add_cleanup(xauthfile_cleanup_proc, NULL);
+ success = 1;
+ break;
+#else /* XAUTH_PATH */
+ packet_send_debug("No xauth program; cannot forward with spoofing.");
+ break;
+#endif /* XAUTH_PATH */
+
+ case SSH_CMSG_AGENT_REQUEST_FORWARDING:
+ if (no_agent_forwarding_flag || compat13) {
+ debug("Authentication agent forwarding not permitted for this authentication.");
+ break;
+ }
+ debug("Received authentication agent forwarding request.");
+ auth_input_request_forwarding(pw);
+ success = 1;
+ break;
+
+ case SSH_CMSG_PORT_FORWARD_REQUEST:
+ if (no_port_forwarding_flag) {
+ debug("Port forwarding not permitted for this authentication.");
+ break;
+ }
+ debug("Received TCP/IP port forwarding request.");
+ channel_input_port_forward_request(pw->pw_uid == 0);
+ success = 1;
+ break;
+
+ case SSH_CMSG_MAX_PACKET_SIZE:
+ if (packet_set_maxsize(packet_get_int()) > 0)
+ success = 1;
+ break;
+
+ case SSH_CMSG_EXEC_SHELL:
+ case SSH_CMSG_EXEC_CMD:
+ /* Set interactive/non-interactive mode. */
+ packet_set_interactive(have_pty || s->display != NULL,
+ options.keepalives);
+
+ if (type == SSH_CMSG_EXEC_CMD) {
+ command = packet_get_string(&dlen);
+ debug("Exec command '%.500s'", command);
+ packet_integrity_check(plen, 4 + dlen, type);
+ } else {
+ command = NULL;
+ packet_integrity_check(plen, 0, type);
+ }
+ if (forced_command != NULL) {
+ command = forced_command;
+ debug("Forced command '%.500s'", forced_command);
+ }
+ if (have_pty)
+ do_exec_pty(s, command, pw);
+ else
+ do_exec_no_pty(s, command, pw);
+
+ if (command != NULL)
+ xfree(command);
+ /* Cleanup user's local Xauthority file. */
+ if (xauthfile)
+ xauthfile_cleanup_proc(NULL);
+ return;
+
+ default:
+ /*
+ * Any unknown messages in this phase are ignored,
+ * and a failure message is returned.
+ */
+ log("Unknown packet type received after authentication: %d", type);
+ }
+ packet_start(success ? SSH_SMSG_SUCCESS : SSH_SMSG_FAILURE);
+ packet_send();
+ packet_write_wait();
+
+ /* Enable compression now that we have replied if appropriate. */
+ if (enable_compression_after_reply) {
+ enable_compression_after_reply = 0;
+ packet_start_compression(compression_level);
+ }
+ }
+}
+
+/*
+ * This is called to fork and execute a command when we have no tty. This
+ * will call do_child from the child, and server_loop from the parent after
+ * setting up file descriptors and such.
+ */
+void
+do_exec_no_pty(Session *s, const char *command, struct passwd * pw)
+{
+ int pid;
+
+#ifdef USE_PIPES
+ int pin[2], pout[2], perr[2];
+ /* Allocate pipes for communicating with the program. */
+ if (pipe(pin) < 0 || pipe(pout) < 0 || pipe(perr) < 0)
+ packet_disconnect("Could not create pipes: %.100s",
+ strerror(errno));
+#else /* USE_PIPES */
+ int inout[2], err[2];
+ /* Uses socket pairs to communicate with the program. */
+ if (socketpair(AF_UNIX, SOCK_STREAM, 0, inout) < 0 ||
+ socketpair(AF_UNIX, SOCK_STREAM, 0, err) < 0)
+ packet_disconnect("Could not create socket pairs: %.100s",
+ strerror(errno));
+#endif /* USE_PIPES */
+ if (s == NULL)
+ fatal("do_exec_no_pty: no session");
+
+ setproctitle("%s@notty", pw->pw_name);
+
+#ifdef USE_PAM
+ do_pam_setcred();
+#endif /* USE_PAM */
+
+ /* Fork the child. */
+ if ((pid = fork()) == 0) {
+ /* Child. Reinitialize the log since the pid has changed. */
+ log_init(__progname, options.log_level, options.log_facility, log_stderr);
+
+ /*
+ * Create a new session and process group since the 4.4BSD
+ * setlogin() affects the entire process group.
+ */
+ if (setsid() < 0)
+ error("setsid failed: %.100s", strerror(errno));
+
+#ifdef USE_PIPES
+ /*
+ * Redirect stdin. We close the parent side of the socket
+ * pair, and make the child side the standard input.
+ */
+ close(pin[1]);
+ if (dup2(pin[0], 0) < 0)
+ perror("dup2 stdin");
+ close(pin[0]);
+
+ /* Redirect stdout. */
+ close(pout[0]);
+ if (dup2(pout[1], 1) < 0)
+ perror("dup2 stdout");
+ close(pout[1]);
+
+ /* Redirect stderr. */
+ close(perr[0]);
+ if (dup2(perr[1], 2) < 0)
+ perror("dup2 stderr");
+ close(perr[1]);
+#else /* USE_PIPES */
+ /*
+ * Redirect stdin, stdout, and stderr. Stdin and stdout will
+ * use the same socket, as some programs (particularly rdist)
+ * seem to depend on it.
+ */
+ close(inout[1]);
+ close(err[1]);
+ if (dup2(inout[0], 0) < 0) /* stdin */
+ perror("dup2 stdin");
+ if (dup2(inout[0], 1) < 0) /* stdout. Note: same socket as stdin. */
+ perror("dup2 stdout");
+ if (dup2(err[0], 2) < 0) /* stderr */
+ perror("dup2 stderr");
+#endif /* USE_PIPES */
+
+ /* Do processing for the child (exec command etc). */
+ do_child(command, pw, NULL, s->display, s->auth_proto, s->auth_data, NULL);
+ /* NOTREACHED */
+ }
+ if (pid < 0)
+ packet_disconnect("fork failed: %.100s", strerror(errno));
+ s->pid = pid;
+#ifdef USE_PIPES
+ /* We are the parent. Close the child sides of the pipes. */
+ close(pin[0]);
+ close(pout[1]);
+ close(perr[1]);
+
+ /* Enter the interactive session. */
+ server_loop(pid, pin[1], pout[0], perr[0]);
+ /* server_loop has closed pin[1], pout[1], and perr[1]. */
+#else /* USE_PIPES */
+ /* We are the parent. Close the child sides of the socket pairs. */
+ close(inout[0]);
+ close(err[0]);
+
+ /*
+ * Enter the interactive session. Note: server_loop must be able to
+ * handle the case that fdin and fdout are the same.
+ */
+ server_loop(pid, inout[1], inout[1], err[1]);
+ /* server_loop has closed inout[1] and err[1]. */
+#endif /* USE_PIPES */
+}
+
+/*
+ * This is called to fork and execute a command when we have a tty. This
+ * will call do_child from the child, and server_loop from the parent after
+ * setting up file descriptors, controlling tty, updating wtmp, utmp,
+ * lastlog, and other such operations.
+ */
+void
+do_exec_pty(Session *s, const char *command, struct passwd * pw)
+{
+ FILE *f;
+ char buf[100], *time_string;
+ char line[256];
+ const char *hostname;
+ int fdout, ptyfd, ttyfd, ptymaster;
+ int quiet_login;
+ pid_t pid;
+ socklen_t fromlen;
+ struct sockaddr_storage from;
+ struct stat st;
+ time_t last_login_time;
+
+ if (s == NULL)
+ fatal("do_exec_pty: no session");
+ ptyfd = s->ptyfd;
+ ttyfd = s->ttyfd;
+
+ /* Get remote host name. */
+ hostname = get_canonical_hostname();
+
+ /*
+ * Get the time when the user last logged in. Buf will be set to
+ * contain the hostname the last login was from.
+ */
+ if (!options.use_login) {
+ last_login_time = get_last_login_time(pw->pw_uid, pw->pw_name,
+ buf, sizeof(buf));
+ }
+ setproctitle("%s@%s", pw->pw_name, strrchr(s->tty, '/') + 1);
+
+#ifdef USE_PAM
+ do_pam_session(pw->pw_name, s->tty);
+ do_pam_setcred();
+#endif /* USE_PAM */
+
+ /* Fork the child. */
+ if ((pid = fork()) == 0) {
+ pid = getpid();
+
+ /* Child. Reinitialize the log because the pid has
+ changed. */
+ log_init(__progname, options.log_level, options.log_facility, log_stderr);
+
+ /* Close the master side of the pseudo tty. */
+ close(ptyfd);
+
+ /* Make the pseudo tty our controlling tty. */
+ pty_make_controlling_tty(&ttyfd, s->tty);
+
+ /* Redirect stdin from the pseudo tty. */
+ if (dup2(ttyfd, fileno(stdin)) < 0)
+ error("dup2 stdin failed: %.100s", strerror(errno));
+
+ /* Redirect stdout to the pseudo tty. */
+ if (dup2(ttyfd, fileno(stdout)) < 0)
+ error("dup2 stdin failed: %.100s", strerror(errno));
+
+ /* Redirect stderr to the pseudo tty. */
+ if (dup2(ttyfd, fileno(stderr)) < 0)
+ error("dup2 stdin failed: %.100s", strerror(errno));
+
+ /* Close the extra descriptor for the pseudo tty. */
+ close(ttyfd);
+
+///XXXX ? move to do_child() ??
+ /*
+ * Get IP address of client. This is needed because we want
+ * to record where the user logged in from. If the
+ * connection is not a socket, let the ip address be 0.0.0.0.
+ */
+ memset(&from, 0, sizeof(from));
+ if (packet_connection_is_on_socket()) {
+ fromlen = sizeof(from);
+ if (getpeername(packet_get_connection_in(),
+ (struct sockaddr *) & from, &fromlen) < 0) {
+ debug("getpeername: %.100s", strerror(errno));
+ fatal_cleanup();
+ }
+ }
+ /* Record that there was a login on that terminal. */
+ record_login(pid, s->tty, pw->pw_name, pw->pw_uid, hostname,
+ (struct sockaddr *)&from);
+
+ /* Check if .hushlogin exists. */
+ snprintf(line, sizeof line, "%.200s/.hushlogin", pw->pw_dir);
+ quiet_login = stat(line, &st) >= 0;
+
+#ifdef USE_PAM
+ if (!quiet_login)
+ print_pam_messages();
+#endif /* USE_PAM */
+
+ /*
+ * If the user has logged in before, display the time of last
+ * login. However, don't display anything extra if a command
+ * has been specified (so that ssh can be used to execute
+ * commands on a remote machine without users knowing they
+ * are going to another machine). Login(1) will do this for
+ * us as well, so check if login(1) is used
+ */
+ if (command == NULL && last_login_time != 0 && !quiet_login &&
+ !options.use_login) {
+ /* Convert the date to a string. */
+ time_string = ctime(&last_login_time);
+ /* Remove the trailing newline. */
+ if (strchr(time_string, '\n'))
+ *strchr(time_string, '\n') = 0;
+ /* Display the last login time. Host if displayed
+ if known. */
+ if (strcmp(buf, "") == 0)
+ printf("Last login: %s\r\n", time_string);
+ else
+ printf("Last login: %s from %s\r\n", time_string, buf);
+ }
+ /*
+ * Print /etc/motd unless a command was specified or printing
+ * it was disabled in server options or login(1) will be
+ * used. Note that some machines appear to print it in
+ * /etc/profile or similar.
+ */
+ if (command == NULL && options.print_motd && !quiet_login &&
+ !options.use_login) {
+ /* Print /etc/motd if it exists. */
+ f = fopen("/etc/motd", "r");
+ if (f) {
+ while (fgets(line, sizeof(line), f))
+ fputs(line, stdout);
+ fclose(f);
+ }
+ }
+ /* Do common processing for the child, such as execing the command. */
+ do_child(command, pw, s->term, s->display, s->auth_proto, s->auth_data, s->tty);
+ /* NOTREACHED */
+ }
+ if (pid < 0)
+ packet_disconnect("fork failed: %.100s", strerror(errno));
+ s->pid = pid;
+
+ /* Parent. Close the slave side of the pseudo tty. */
+ close(ttyfd);
+
+ /*
+ * Create another descriptor of the pty master side for use as the
+ * standard input. We could use the original descriptor, but this
+ * simplifies code in server_loop. The descriptor is bidirectional.
+ */
+ fdout = dup(ptyfd);
+ if (fdout < 0)
+ packet_disconnect("dup #1 failed: %.100s", strerror(errno));
+
+ /* we keep a reference to the pty master */
+ ptymaster = dup(ptyfd);
+ if (ptymaster < 0)
+ packet_disconnect("dup #2 failed: %.100s", strerror(errno));
+ s->ptymaster = ptymaster;
+
+ /* Enter interactive session. */
+ server_loop(pid, ptyfd, fdout, -1);
+ /* server_loop _has_ closed ptyfd and fdout. */
+ session_pty_cleanup(s);
+}
+
+/*
+ * Sets the value of the given variable in the environment. If the variable
+ * already exists, its value is overriden.
+ */
+void
+child_set_env(char ***envp, unsigned int *envsizep, const char *name,
+ const char *value)
+{
+ unsigned int i, namelen;
+ char **env;
+
+ /*
+ * Find the slot where the value should be stored. If the variable
+ * already exists, we reuse the slot; otherwise we append a new slot
+ * at the end of the array, expanding if necessary.
+ */
+ env = *envp;
+ namelen = strlen(name);
+ for (i = 0; env[i]; i++)
+ if (strncmp(env[i], name, namelen) == 0 && env[i][namelen] == '=')
+ break;
+ if (env[i]) {
+ /* Reuse the slot. */
+ xfree(env[i]);
+ } else {
+ /* New variable. Expand if necessary. */
+ if (i >= (*envsizep) - 1) {
+ (*envsizep) += 50;
+ env = (*envp) = xrealloc(env, (*envsizep) * sizeof(char *));
+ }
+ /* Need to set the NULL pointer at end of array beyond the new slot. */
+ env[i + 1] = NULL;
+ }
+
+ /* Allocate space and format the variable in the appropriate slot. */
+ env[i] = xmalloc(strlen(name) + 1 + strlen(value) + 1);
+ snprintf(env[i], strlen(name) + 1 + strlen(value) + 1, "%s=%s", name, value);
+}
+
+/*
+ * Reads environment variables from the given file and adds/overrides them
+ * into the environment. If the file does not exist, this does nothing.
+ * Otherwise, it must consist of empty lines, comments (line starts with '#')
+ * and assignments of the form name=value. No other forms are allowed.
+ */
+void
+read_environment_file(char ***env, unsigned int *envsize,
+ const char *filename)
+{
+ FILE *f;
+ char buf[4096];
+ char *cp, *value;
+
+ f = fopen(filename, "r");
+ if (!f)
+ return;
+
+ while (fgets(buf, sizeof(buf), f)) {
+ for (cp = buf; *cp == ' ' || *cp == '\t'; cp++)
+ ;
+ if (!*cp || *cp == '#' || *cp == '\n')
+ continue;
+ if (strchr(cp, '\n'))
+ *strchr(cp, '\n') = '\0';
+ value = strchr(cp, '=');
+ if (value == NULL) {
+ fprintf(stderr, "Bad line in %.100s: %.200s\n", filename, buf);
+ continue;
+ }
+ /* Replace the equals sign by nul, and advance value to the value string. */
+ *value = '\0';
+ value++;
+ child_set_env(env, envsize, cp, value);
+ }
+ fclose(f);
+}
+
+#ifdef USE_PAM
+/*
+ * Sets any environment variables which have been specified by PAM
+ */
+void do_pam_environment(char ***env, int *envsize)
+{
+ char *equals, var_name[512], var_val[512];
+ char **pam_env;
+ int i;
+
+ if ((pam_env = fetch_pam_environment()) == NULL)
+ return;
+
+ for(i = 0; pam_env[i] != NULL; i++) {
+ if ((equals = strstr(pam_env[i], "=")) == NULL)
+ continue;
+
+ if (strlen(pam_env[i]) < (sizeof(var_name) - 1)) {
+ memset(var_name, '\0', sizeof(var_name));
+ memset(var_val, '\0', sizeof(var_val));
+
+ strncpy(var_name, pam_env[i], equals - pam_env[i]);
+ strcpy(var_val, equals + 1);
+
+ debug("PAM environment: %s=%s", var_name, var_val);
+
+ child_set_env(env, envsize, var_name, var_val);
+ }
+ }
+}
+#endif /* USE_PAM */
+
+/*
+ * Performs common processing for the child, such as setting up the
+ * environment, closing extra file descriptors, setting the user and group
+ * ids, and executing the command or shell.
+ */
+void
+do_child(const char *command, struct passwd * pw, const char *term,
+ const char *display, const char *auth_proto,
+ const char *auth_data, const char *ttyname)
+{
+ const char *shell, *cp = NULL;
+ char buf[256];
+ FILE *f;
+ unsigned int envsize, i;
+ char **env;
+ extern char **environ;
+ struct stat st;
+ char *argv[10];
+
+#ifndef USE_PAM /* pam_nologin handles this */
+ f = fopen("/etc/nologin", "r");
+ if (f) {
+ /* /etc/nologin exists. Print its contents and exit. */
+ while (fgets(buf, sizeof(buf), f))
+ fputs(buf, stderr);
+ fclose(f);
+ if (pw->pw_uid != 0)
+ exit(254);
+ }
+#endif /* USE_PAM */
+
+ /* Set login name in the kernel. */
+ if (setlogin(pw->pw_name) < 0)
+ error("setlogin failed: %s", strerror(errno));
+
+ /* Set uid, gid, and groups. */
+ /* Login(1) does this as well, and it needs uid 0 for the "-h"
+ switch, so we let login(1) to this for us. */
+ if (!options.use_login) {
+ if (getuid() == 0 || geteuid() == 0) {
+ if (setgid(pw->pw_gid) < 0) {
+ perror("setgid");
+ exit(1);
+ }
+ /* Initialize the group list. */
+ if (initgroups(pw->pw_name, pw->pw_gid) < 0) {
+ perror("initgroups");
+ exit(1);
+ }
+ endgrent();
+
+ /* Permanently switch to the desired uid. */
+ permanently_set_uid(pw->pw_uid);
+ }
+ if (getuid() != pw->pw_uid || geteuid() != pw->pw_uid)
+ fatal("Failed to set uids to %d.", (int) pw->pw_uid);
+ }
+ /*
+ * Get the shell from the password data. An empty shell field is
+ * legal, and means /bin/sh.
+ */
+ shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell;
+
+#ifdef AFS
+ /* Try to get AFS tokens for the local cell. */
+ if (k_hasafs()) {
+ char cell[64];
+
+ if (k_afs_cell_of_file(pw->pw_dir, cell, sizeof(cell)) == 0)
+ krb_afslog(cell, 0);
+
+ krb_afslog(0, 0);
+ }
+#endif /* AFS */
+
+ /* Initialize the environment. */
+ envsize = 100;
+ env = xmalloc(envsize * sizeof(char *));
+ env[0] = NULL;
+
+ if (!options.use_login) {
+ /* Set basic environment. */
+ child_set_env(&env, &envsize, "USER", pw->pw_name);
+ child_set_env(&env, &envsize, "LOGNAME", pw->pw_name);
+ child_set_env(&env, &envsize, "HOME", pw->pw_dir);
+ child_set_env(&env, &envsize, "PATH", _PATH_STDPATH);
+
+ snprintf(buf, sizeof buf, "%.200s/%.50s",
+ _PATH_MAILDIR, pw->pw_name);
+ child_set_env(&env, &envsize, "MAIL", buf);
+
+ /* Normal systems set SHELL by default. */
+ child_set_env(&env, &envsize, "SHELL", shell);
+ }
+ if (getenv("TZ"))
+ child_set_env(&env, &envsize, "TZ", getenv("TZ"));
+
+ /* Set custom environment options from RSA authentication. */
+ while (custom_environment) {
+ struct envstring *ce = custom_environment;
+ char *s = ce->s;
+ int i;
+ for (i = 0; s[i] != '=' && s[i]; i++);
+ if (s[i] == '=') {
+ s[i] = 0;
+ child_set_env(&env, &envsize, s, s + i + 1);
+ }
+ custom_environment = ce->next;
+ xfree(ce->s);
+ xfree(ce);
+ }
+
+ snprintf(buf, sizeof buf, "%.50s %d %d",
+ get_remote_ipaddr(), get_remote_port(), get_local_port());
+ child_set_env(&env, &envsize, "SSH_CLIENT", buf);
+
+ if (ttyname)
+ child_set_env(&env, &envsize, "SSH_TTY", ttyname);
+ if (term)
+ child_set_env(&env, &envsize, "TERM", term);
+ if (display)
+ child_set_env(&env, &envsize, "DISPLAY", display);
+
+#ifdef _AIX
+ {
+ char *authstate,*krb5cc;
+
+ if ((authstate = getenv("AUTHSTATE")) != NULL)
+ child_set_env(&env,&envsize,"AUTHSTATE",authstate);
+
+ if ((krb5cc = getenv("KRB5CCNAME")) != NULL)
+ child_set_env(&env,&envsize,"KRB5CCNAME",krb5cc);
+ }
+#endif
+
+#ifdef KRB4
+ {
+ extern char *ticket;
+
+ if (ticket)
+ child_set_env(&env, &envsize, "KRBTKFILE", ticket);
+ }
+#endif /* KRB4 */
+
+#ifdef USE_PAM
+ /* Pull in any environment variables that may have been set by PAM. */
+ do_pam_environment(&env, &envsize);
+#endif /* USE_PAM */
+
+ read_environment_file(&env,&envsize,"/etc/environment");
+
+ if (xauthfile)
+ child_set_env(&env, &envsize, "XAUTHORITY", xauthfile);
+ if (auth_get_socket_name() != NULL)
+ child_set_env(&env, &envsize, SSH_AUTHSOCKET_ENV_NAME,
+ auth_get_socket_name());
+
+ /* read $HOME/.ssh/environment. */
+ if (!options.use_login) {
+ snprintf(buf, sizeof buf, "%.200s/.ssh/environment", pw->pw_dir);
+ read_environment_file(&env, &envsize, buf);
+ }
+ if (debug_flag) {
+ /* dump the environment */
+ fprintf(stderr, "Environment:\n");
+ for (i = 0; env[i]; i++)
+ fprintf(stderr, " %.200s\n", env[i]);
+ }
+ /*
+ * Close the connection descriptors; note that this is the child, and
+ * the server will still have the socket open, and it is important
+ * that we do not shutdown it. Note that the descriptors cannot be
+ * closed before building the environment, as we call
+ * get_remote_ipaddr there.
+ */
+ if (packet_get_connection_in() == packet_get_connection_out())
+ close(packet_get_connection_in());
+ else {
+ close(packet_get_connection_in());
+ close(packet_get_connection_out());
+ }
+ /*
+ * Close all descriptors related to channels. They will still remain
+ * open in the parent.
+ */
+ /* XXX better use close-on-exec? -markus */
+ channel_close_all();
+
+ /*
+ * Close any extra file descriptors. Note that there may still be
+ * descriptors left by system functions. They will be closed later.
+ */
+ endpwent();
+
+ /*
+ * Close any extra open file descriptors so that we don\'t have them
+ * hanging around in clients. Note that we want to do this after
+ * initgroups, because at least on Solaris 2.3 it leaves file
+ * descriptors open.
+ */
+ for (i = 3; i < 64; i++)
+ close(i);
+
+ /* Change current directory to the user\'s home directory. */
+ if (chdir(pw->pw_dir) < 0)
+ fprintf(stderr, "Could not chdir to home directory %s: %s\n",
+ pw->pw_dir, strerror(errno));
+
+ /*
+ * Must take new environment into use so that .ssh/rc, /etc/sshrc and
+ * xauth are run in the proper environment.
+ */
+ environ = env;
+
+ /*
+ * Run $HOME/.ssh/rc, /etc/sshrc, or xauth (whichever is found first
+ * in this order).
+ */
+ if (!options.use_login) {
+ if (stat(SSH_USER_RC, &st) >= 0) {
+ if (debug_flag)
+ fprintf(stderr, "Running /bin/sh %s\n", SSH_USER_RC);
+
+ f = popen("/bin/sh " SSH_USER_RC, "w");
+ if (f) {
+ if (auth_proto != NULL && auth_data != NULL)
+ fprintf(f, "%s %s\n", auth_proto, auth_data);
+ pclose(f);
+ } else
+ fprintf(stderr, "Could not run %s\n", SSH_USER_RC);
+ } else if (stat(SSH_SYSTEM_RC, &st) >= 0) {
+ if (debug_flag)
+ fprintf(stderr, "Running /bin/sh %s\n", SSH_SYSTEM_RC);
+
+ f = popen("/bin/sh " SSH_SYSTEM_RC, "w");
+ if (f) {
+ if (auth_proto != NULL && auth_data != NULL)
+ fprintf(f, "%s %s\n", auth_proto, auth_data);
+ pclose(f);
+ } else
+ fprintf(stderr, "Could not run %s\n", SSH_SYSTEM_RC);
+ }
+#ifdef XAUTH_PATH
+ else {
+ /* Add authority data to .Xauthority if appropriate. */
+ if (auth_proto != NULL && auth_data != NULL) {
+ if (debug_flag)
+ fprintf(stderr, "Running %.100s add %.100s %.100s %.100s\n",
+ XAUTH_PATH, display, auth_proto, auth_data);
+
+ f = popen(XAUTH_PATH " -q -", "w");
+ if (f) {
+ fprintf(f, "add %s %s %s\n", display, auth_proto, auth_data);
+ pclose(f);
+ } else
+ fprintf(stderr, "Could not run %s -q -\n", XAUTH_PATH);
+ }
+ }
+#endif /* XAUTH_PATH */
+
+ /* Get the last component of the shell name. */
+ cp = strrchr(shell, '/');
+ if (cp)
+ cp++;
+ else
+ cp = shell;
+ }
+ /*
+ * If we have no command, execute the shell. In this case, the shell
+ * name to be passed in argv[0] is preceded by '-' to indicate that
+ * this is a login shell.
+ */
+ if (!command) {
+ if (!options.use_login) {
+ char buf[256];
+
+ /*
+ * Check for mail if we have a tty and it was enabled
+ * in server options.
+ */
+ if (ttyname && options.check_mail) {
+ char *mailbox;
+ struct stat mailstat;
+ mailbox = getenv("MAIL");
+ if (mailbox != NULL) {
+ if (stat(mailbox, &mailstat) != 0 || mailstat.st_size == 0)
+ printf("No mail.\n");
+ else if (mailstat.st_mtime < mailstat.st_atime)
+ printf("You have mail.\n");
+ else
+ printf("You have new mail.\n");
+ }
+ }
+ /* Start the shell. Set initial character to '-'. */
+ buf[0] = '-';
+ strncpy(buf + 1, cp, sizeof(buf) - 1);
+ buf[sizeof(buf) - 1] = 0;
+
+ /* Execute the shell. */
+ argv[0] = buf;
+ argv[1] = NULL;
+ execve(shell, argv, env);
+
+ /* Executing the shell failed. */
+ perror(shell);
+ exit(1);
+
+ } else {
+ /* Launch login(1). */
+
+ execl("/usr/bin/login", "login", "-h", get_remote_ipaddr(),
+ "-p", "-f", "--", pw->pw_name, NULL);
+
+ /* Login couldn't be executed, die. */
+
+ perror("login");
+ exit(1);
+ }
+ }
+ /*
+ * Execute the command using the user's shell. This uses the -c
+ * option to execute the command.
+ */
+ argv[0] = (char *) cp;
+ argv[1] = "-c";
+ argv[2] = (char *) command;
+ argv[3] = NULL;
+ execve(shell, argv, env);
+ perror(shell);
+ exit(1);
+}
+
+Session *
+session_new(void)
+{
+ int i;
+ static int did_init = 0;
+ if (!did_init) {
+ debug("session_new: init");
+ for(i = 0; i < MAX_SESSIONS; i++) {
+ sessions[i].used = 0;
+ sessions[i].self = i;
+ }
+ did_init = 1;
+ }
+ for(i = 0; i < MAX_SESSIONS; i++) {
+ Session *s = &sessions[i];
+ if (! s->used) {
+ s->pid = 0;
+ s->chanid = -1;
+ s->ptyfd = -1;
+ s->ttyfd = -1;
+ s->term = NULL;
+ s->pw = NULL;
+ s->display = NULL;
+ s->screen = 0;
+ s->auth_data = NULL;
+ s->auth_proto = NULL;
+ s->used = 1;
+ debug("session_new: session %d", i);
+ return s;
+ }
+ }
+ return NULL;
+}
+
+void
+session_dump(void)
+{
+ int i;
+ for(i = 0; i < MAX_SESSIONS; i++) {
+ Session *s = &sessions[i];
+ debug("dump: used %d session %d %p channel %d pid %d",
+ s->used,
+ s->self,
+ s,
+ s->chanid,
+ s->pid);
+ }
+}
+
+void
+session_pty_cleanup(Session *s)
+{
+ if (s == NULL || s->ttyfd == -1)
+ return;
+
+ debug("session_pty_cleanup: session %i release %s", s->self, s->tty);
+
+ /* Cancel the cleanup function. */
+ fatal_remove_cleanup(pty_cleanup_proc, (void *)s);
+
+ /* Record that the user has logged out. */
+ record_logout(s->pid, s->tty);
+
+ /* Release the pseudo-tty. */
+ pty_release(s->tty);
+
+ /*
+ * Close the server side of the socket pairs. We must do this after
+ * the pty cleanup, so that another process doesn't get this pty
+ * while we're still cleaning up.
+ */
+ if (close(s->ptymaster) < 0)
+ error("close(s->ptymaster): %s", strerror(errno));
+}
--- /dev/null
+#ifndef SESSION_H
+#define SESSION_H
+
+/* SSH1 */
+void do_authenticated(struct passwd * pw);
+
+#endif
#include "authfd.h"
#include "readconf.h"
#include "uidswap.h"
+#include "channels.h"
#ifdef HAVE___PROGNAME
extern char *__progname;
/* Removes a cleanup function to be called at fatal(). */
void fatal_remove_cleanup(void (*proc) (void *context), void *context);
-/*---------------- definitions for channels ------------------*/
-
-/* Sets specific protocol options. */
-void channel_set_options(int hostname_in_open);
-
-/*
- * Allocate a new channel object and set its type and socket. Remote_name
- * must have been allocated with xmalloc; this will free it when the channel
- * is freed.
- */
-int channel_allocate(int type, int sock, char *remote_name);
-
-/* Free the channel and close its socket. */
-void channel_free(int channel);
-
-/* Add any bits relevant to channels in select bitmasks. */
-void channel_prepare_select(fd_set * readset, fd_set * writeset);
-
-/*
- * After select, perform any appropriate operations for channels which have
- * events pending.
- */
-void channel_after_select(fd_set * readset, fd_set * writeset);
-
-/* If there is data to send to the connection, send some of it now. */
-void channel_output_poll(void);
-
-/*
- * This is called when a packet of type CHANNEL_DATA has just been received.
- * The message type has already been consumed, but channel number and data is
- * still there.
- */
-void channel_input_data(int payload_len);
-
-/* Returns true if no channel has too much buffered data. */
-int channel_not_very_much_buffered_data(void);
-
-/* This is called after receiving CHANNEL_CLOSE. */
-void channel_input_close(void);
-
-/* This is called after receiving CHANNEL_CLOSE_CONFIRMATION. */
-void channel_input_close_confirmation(void);
-
-/* This is called after receiving CHANNEL_OPEN_CONFIRMATION. */
-void channel_input_open_confirmation(void);
-
-/* This is called after receiving CHANNEL_OPEN_FAILURE from the other side. */
-void channel_input_open_failure(void);
-
-/* This closes any sockets that are listening for connections; this removes
- any unix domain sockets. */
-void channel_stop_listening(void);
-
-/*
- * Closes the sockets of all channels. This is used to close extra file
- * descriptors after a fork.
- */
-void channel_close_all(void);
-
-/* Returns the maximum file descriptor number used by the channels. */
-int channel_max_fd(void);
-
-/* Returns true if there is still an open channel over the connection. */
-int channel_still_open(void);
-
-/*
- * Returns a string containing a list of all open channels. The list is
- * suitable for displaying to the user. It uses crlf instead of newlines.
- * The caller should free the string with xfree.
- */
-char *channel_open_message(void);
-
-/*
- * Initiate forwarding of connections to local port "port" through the secure
- * channel to host:port from remote side. This never returns if there was an
- * error.
- */
-void
-channel_request_local_forwarding(u_short port, const char *host,
- u_short remote_port, int gateway_ports);
-
-/*
- * Initiate forwarding of connections to port "port" on remote host through
- * the secure channel to host:port from local side. This never returns if
- * there was an error. This registers that open requests for that port are
- * permitted.
- */
-void
-channel_request_remote_forwarding(u_short port, const char *host,
- u_short remote_port);
-
-/*
- * Permits opening to any host/port in SSH_MSG_PORT_OPEN. This is usually
- * called by the server, because the user could connect to any port anyway,
- * and the server has no way to know but to trust the client anyway.
- */
-void channel_permit_all_opens(void);
-
-/*
- * This is called after receiving CHANNEL_FORWARDING_REQUEST. This initates
- * listening for the port, and sends back a success reply (or disconnect
- * message if there was an error). This never returns if there was an error.
- */
-void channel_input_port_forward_request(int is_root);
-
-/*
- * This is called after receiving PORT_OPEN message. This attempts to
- * connect to the given host:port, and sends back CHANNEL_OPEN_CONFIRMATION
- * or CHANNEL_OPEN_FAILURE.
- */
-void channel_input_port_open(int payload_len);
-
-/*
- * Creates a port for X11 connections, and starts listening for it. Returns
- * the display name, or NULL if an error was encountered.
- */
-char *x11_create_display(int screen);
-
-/*
- * Creates an internet domain socket for listening for X11 connections.
- * Returns a suitable value for the DISPLAY variable, or NULL if an error
- * occurs.
- */
-char *x11_create_display_inet(int screen, int x11_display_offset);
-
-/*
- * This is called when SSH_SMSG_X11_OPEN is received. The packet contains
- * the remote channel number. We should do whatever we want, and respond
- * with either SSH_MSG_OPEN_CONFIRMATION or SSH_MSG_OPEN_FAILURE.
- */
-void x11_input_open(int payload_len);
-
-/*
- * Requests forwarding of X11 connections. This should be called on the
- * client only.
- */
-void x11_request_forwarding(void);
-
-/*
- * Requests forwarding for X11 connections, with authentication spoofing.
- * This should be called in the client only.
- */
-void x11_request_forwarding_with_spoofing(const char *proto, const char *data);
-
-/* Sends a message to the server to request authentication fd forwarding. */
-void auth_request_forwarding(void);
-
-/*
- * Returns the name of the forwarded authentication socket. Returns NULL if
- * there is no forwarded authentication socket. The returned value points to
- * a static buffer.
- */
-char *auth_get_socket_name(void);
-
-/*
- * This if called to process SSH_CMSG_AGENT_REQUEST_FORWARDING on the server.
- * This starts forwarding authentication requests.
- */
-void auth_input_request_forwarding(struct passwd * pw);
-
-/* This is called to process an SSH_SMSG_AGENT_OPEN message. */
-void auth_input_open_request(void);
-
-/*
- * Returns true if the given string matches the pattern (which may contain ?
- * and * as wildcards), and zero if it does not match.
- */
-int match_pattern(const char *s, const char *pattern);
-
/*
* Expands tildes in the file name. Returns data allocated by xmalloc.
* Warning: this calls getpw*.
--- /dev/null
+/*
+ * draft-ietf-secsh-architecture-04.txt
+ *
+ * Transport layer protocol:
+ *
+ * 1-19 Transport layer generic (e.g. disconnect, ignore, debug,
+ * etc)
+ * 20-29 Algorithm negotiation
+ * 30-49 Key exchange method specific (numbers can be reused for
+ * different authentication methods)
+ *
+ * User authentication protocol:
+ *
+ * 50-59 User authentication generic
+ * 60-79 User authentication method specific (numbers can be reused
+ * for different authentication methods)
+ *
+ * Connection protocol:
+ *
+ * 80-89 Connection protocol generic
+ * 90-127 Channel related messages
+ *
+ * Reserved for client protocols:
+ *
+ * 128-191 Reserved
+ *
+ * Local extensions:
+ *
+ * 192-255 Local extensions
+ */
+
+/* transport layer: generic */
+
+#define SSH2_MSG_DISCONNECT 1
+#define SSH2_MSG_IGNORE 2
+#define SSH2_MSG_UNIMPLEMENTED 3
+#define SSH2_MSG_DEBUG 4
+#define SSH2_MSG_SERVICE_REQUEST 5
+#define SSH2_MSG_SERVICE_ACCEPT 6
+
+/* transport layer: alg negotiation */
+
+#define SSH2_MSG_KEXINIT 20
+#define SSH2_MSG_NEWKEYS 21
+
+/* transport layer: kex specific messages, can be reused */
+
+#define SSH2_MSG_KEXDH_INIT 30
+#define SSH2_MSG_KEXDH_REPLY 31
+
+/* user authentication: generic */
+
+#define SSH2_MSG_USERAUTH_REQUEST 50
+#define SSH2_MSG_USERAUTH_FAILURE 51
+#define SSH2_MSG_USERAUTH_SUCCESS 52
+#define SSH2_MSG_USERAUTH_BANNER 53
+
+/* user authentication: method specific, can be reused */
+
+#define SSH2_MSG_USERAUTH_PK_OK 60
+#define SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ 60
+#define SSH2_MSG_USERAUTH_INFO_REQUEST 60
+#define SSH2_MSG_USERAUTH_INFO_RESPONSE 61
+
+/* connection protocol: generic */
+
+#define SSH2_MSG_GLOBAL_REQUEST 80
+#define SSH2_MSG_REQUEST_SUCCESS 81
+#define SSH2_MSG_REQUEST_FAILURE 82
+
+/* channel related messages */
+
+#define SSH2_MSG_CHANNEL_OPEN 90
+#define SSH2_MSG_CHANNEL_OPEN_CONFIRMATION 91
+#define SSH2_MSG_CHANNEL_OPEN_FAILURE 92
+#define SSH2_MSG_CHANNEL_WINDOW_ADJUST 93
+#define SSH2_MSG_CHANNEL_DATA 94
+#define SSH2_MSG_CHANNEL_EXTENDED_DATA 95
+#define SSH2_MSG_CHANNEL_EOF 96
+#define SSH2_MSG_CHANNEL_CLOSE 97
+#define SSH2_MSG_CHANNEL_REQUEST 98
+#define SSH2_MSG_CHANNEL_SUCCESS 99
+#define SSH2_MSG_CHANNEL_FAILURE 100
+
+/* disconnect reason code */
+
+#define SSH2_DISCONNECT_HOST_NOT_ALLOWED_TO_CONNECT 1
+#define SSH2_DISCONNECT_PROTOCOL_ERROR 2
+#define SSH2_DISCONNECT_KEY_EXCHANGE_FAILED 3
+#define SSH2_DISCONNECT_HOST_AUTHENTICATION_FAILED 4
+#define SSH2_DISCONNECT_MAC_ERROR 5
+#define SSH2_DISCONNECT_COMPRESSION_ERROR 6
+#define SSH2_DISCONNECT_SERVICE_NOT_AVAILABLE 7
+#define SSH2_DISCONNECT_PROTOCOL_VERSION_NOT_SUPPORTED 8
+#define SSH2_DISCONNECT_HOST_KEY_NOT_VERIFIABLE 9
+#define SSH2_DISCONNECT_CONNECTION_LOST 10
+#define SSH2_DISCONNECT_BY_APPLICATION 11
+
+/* misc */
+
+#define SSH2_OPEN_ADMINISTRATIVELY_PROHIBITED 1
+#define SSH2_OPEN_CONNECT_FAILED 2
+#define SSH2_OPEN_UNKNOWN_CHANNEL_TYPE 3
+#define SSH2_OPEN_RESOURCE_SHORTAGE 4
+
+#define SSH2_EXTENDED_DATA_STDERR 1
communications in the session.
The rest of the session is encrypted
using a conventional cipher, currently Blowfish and 3DES, with 3DES
-being is used by default.
+being used by default.
The client selects the encryption algorithm
to use from those offered by the server.
.Pp
.Xr ssl 8
are required for proper operation.
.Sh SEE ALSO
-.Xr rlogin 1 ,
-.Xr rsh 1 ,
.Xr scp 1 ,
.Xr ssh 1 ,
.Xr ssh-add 1 ,
.Xr ssh-agent 1 ,
.Xr ssh-keygen 1 ,
-.Xr ssl 8
+.Xr ssl 8 ,
+.Xr rlogin 1 ,
+.Xr rsh 1
*/
#include "includes.h"
-RCSID("$OpenBSD: sshd.c,v 1.94 2000/03/23 22:15:34 markus Exp $");
+RCSID("$OpenBSD: sshd.c,v 1.96 2000/03/28 21:15:45 markus Exp $");
#include "xmalloc.h"
#include "rsa.h"
#include "ssh.h"
#include "pty.h"
#include "packet.h"
-#include "buffer.h"
#include "cipher.h"
#include "mpaux.h"
#include "servconf.h"
#include "uidswap.h"
#include "compat.h"
+#include "buffer.h"
+
+#ifdef HAVE_OPENSSL
+# include <openssl/dh.h>
+# include <openssl/bn.h>
+# include <openssl/hmac.h>
+# include <openssl/dsa.h>
+# include <openssl/rsa.h>
+#endif
+#ifdef HAVE_SSL
+# include <ssl/dh.h>
+# include <ssl/bn.h>
+# include <ssl/hmac.h>
+# include <ssl/dsa.h>
+# include <ssl/rsa.h>
+#endif
+#include "key.h"
+
+#include "auth.h"
#ifdef LIBWRAP
#include <tcpd.h>
#define O_NOCTTY 0
#endif
-/* Local Xauthority file. */
-static char *xauthfile = NULL;
-
/* Server configuration options. */
ServerOptions options;
* sshd will skip the version-number exchange
*/
char *client_version_string = NULL;
-
-/* Flags set in auth-rsa from authorized_keys flags. These are set in auth-rsa.c. */
-int no_port_forwarding_flag = 0;
-int no_agent_forwarding_flag = 0;
-int no_x11_forwarding_flag = 0;
-int no_pty_flag = 0;
-
-/* RSA authentication "command=" option. */
-char *forced_command = NULL;
-
-/* RSA authentication "environment=" options. */
-struct envstring *custom_environment = NULL;
-
-/* Session id for the current session. */
-unsigned char session_id[16];
+char *server_version_string = NULL;
/*
* Any really sensitive data in the application is contained in this
the private key. */
RSA *public_key;
-/* Prototypes for various functions defined later in this file. */
-void do_ssh_kex();
-void do_authentication();
-void do_authloop(struct passwd * pw);
-void do_fake_authloop(char *user);
-void do_authenticated(struct passwd * pw);
-void do_exec_pty(const char *command, int ptyfd, int ttyfd,
- const char *ttyname, struct passwd * pw, const char *term,
- const char *display, const char *auth_proto,
- const char *auth_data);
-void do_exec_no_pty(const char *command, struct passwd * pw,
- const char *display, const char *auth_proto,
- const char *auth_data);
-void do_child(const char *command, struct passwd * pw, const char *term,
- const char *display, const char *auth_proto,
- const char *auth_data, const char *ttyname);
+/* session identifier, used by RSA-auth */
+unsigned char session_id[16];
-/*
- * Remove local Xauthority file.
- */
-void
-xauthfile_cleanup_proc(void *ignore)
-{
- debug("xauthfile_cleanup_proc called");
-
- if (xauthfile != NULL) {
- char *p;
- unlink(xauthfile);
- p = strrchr(xauthfile, '/');
- if (p != NULL) {
- *p = '\0';
- rmdir(xauthfile);
- }
- xfree(xauthfile);
- xauthfile = NULL;
- }
-}
+/* Prototypes for various functions defined later in this file. */
+void do_ssh1_kex();
/*
* Close all listening sockets
fatal("Timeout before authentication for %s.", get_remote_ipaddr());
}
-/*
- * convert ssh auth msg type into description
- */
-char *
-get_authname(int type)
-{
- static char buf[1024];
- switch (type) {
- case SSH_CMSG_AUTH_PASSWORD:
- return "password";
- case SSH_CMSG_AUTH_RSA:
- return "rsa";
- case SSH_CMSG_AUTH_RHOSTS_RSA:
- return "rhosts-rsa";
- case SSH_CMSG_AUTH_RHOSTS:
- return "rhosts";
-#ifdef KRB4
- case SSH_CMSG_AUTH_KERBEROS:
- return "kerberos";
-#endif
-#ifdef SKEY
- case SSH_CMSG_AUTH_TIS_RESPONSE:
- return "s/key";
-#endif
- }
- snprintf(buf, sizeof buf, "bad-auth-msg-%d", type);
- return buf;
-}
-
/*
* Signal handler for the key regeneration alarm. Note that this
* alarm only occurs in the daemon waiting for connections, and it does not
errno = save_errno;
}
+void
+sshd_exchange_identification(int sock_in, int sock_out)
+{
+ int i;
+ int remote_major, remote_minor;
+ char *s;
+ char buf[256]; /* Must not be larger than remote_version. */
+ char remote_version[256]; /* Must be at least as big as buf. */
+
+ snprintf(buf, sizeof buf, "SSH-%d.%d-%.100s\n",
+ PROTOCOL_MAJOR, PROTOCOL_MINOR, SSH_VERSION);
+ server_version_string = xstrdup(buf);
+
+ if (client_version_string == NULL) {
+ /* Send our protocol version identification. */
+ if (atomicio(write, sock_out, server_version_string, strlen(server_version_string))
+ != strlen(server_version_string)) {
+ log("Could not write ident string to %s.", get_remote_ipaddr());
+ fatal_cleanup();
+ }
+
+ /* Read other side\'s version identification. */
+ for (i = 0; i < sizeof(buf) - 1; i++) {
+ if (read(sock_in, &buf[i], 1) != 1) {
+ log("Did not receive ident string from %s.", get_remote_ipaddr());
+ fatal_cleanup();
+ }
+ if (buf[i] == '\r') {
+ buf[i] = '\n';
+ buf[i + 1] = 0;
+ continue;
+ /*break; XXX eat \r */
+ }
+ if (buf[i] == '\n') {
+ /* buf[i] == '\n' */
+ buf[i + 1] = 0;
+ break;
+ }
+ }
+ buf[sizeof(buf) - 1] = 0;
+ client_version_string = xstrdup(buf);
+ }
+
+ /*
+ * Check that the versions match. In future this might accept
+ * several versions and set appropriate flags to handle them.
+ */
+ if (sscanf(client_version_string, "SSH-%d.%d-%[^\n]\n",
+ &remote_major, &remote_minor, remote_version) != 3) {
+ s = "Protocol mismatch.\n";
+ (void) atomicio(write, sock_out, s, strlen(s));
+ close(sock_in);
+ close(sock_out);
+ log("Bad protocol version identification '%.100s' from %s",
+ client_version_string, get_remote_ipaddr());
+ fatal_cleanup();
+ }
+ debug("Client protocol version %d.%d; client software version %.100s",
+ remote_major, remote_minor, remote_version);
+
+ switch(remote_major) {
+ case 1:
+ if (remote_minor < 3) {
+ packet_disconnect("Your ssh version is too old and"
+ "is no longer supported. Please install a newer version.");
+ } else if (remote_minor == 3) {
+ /* note that this disables agent-forwarding */
+ enable_compat13();
+ }
+ break;
+ default:
+ s = "Protocol major versions differ.\n";
+ (void) atomicio(write, sock_out, s, strlen(s));
+ close(sock_in);
+ close(sock_out);
+ log("Protocol major versions differ for %s: %d vs. %d",
+ get_remote_ipaddr(), PROTOCOL_MAJOR, remote_major);
+ fatal_cleanup();
+ break;
+ }
+}
+
/*
* Main program for the daemon.
*/
extern int optind;
int opt, sock_in = 0, sock_out = 0, newsock, i, fdsetsz, pid, on = 1;
socklen_t fromlen;
- int remote_major, remote_minor;
int silentrsa = 0;
fd_set *fdset;
struct sockaddr_storage from;
- char buf[100]; /* Must not be larger than remote_version. */
- char remote_version[100]; /* Must be at least as big as buf. */
const char *remote_ip;
int remote_port;
char *comment;
if (!debug_flag)
alarm(options.login_grace_time);
- if (client_version_string != NULL) {
- /* we are exec'ed by sshd2, so skip exchange of protocol version */
- strlcpy(buf, client_version_string, sizeof(buf));
- } else {
- /* Send our protocol version identification. */
- snprintf(buf, sizeof buf, "SSH-%d.%d-%.100s\n",
- PROTOCOL_MAJOR, PROTOCOL_MINOR, SSH_VERSION);
- if (atomicio(write, sock_out, buf, strlen(buf)) != strlen(buf)) {
- log("Could not write ident string to %s.", remote_ip);
- fatal_cleanup();
- }
-
- /* Read other side\'s version identification. */
- for (i = 0; i < sizeof(buf) - 1; i++) {
- if (read(sock_in, &buf[i], 1) != 1) {
- log("Did not receive ident string from %s.", remote_ip);
- fatal_cleanup();
- }
- if (buf[i] == '\r') {
- buf[i] = '\n';
- buf[i + 1] = 0;
- break;
- }
- if (buf[i] == '\n') {
- /* buf[i] == '\n' */
- buf[i + 1] = 0;
- break;
- }
- }
- buf[sizeof(buf) - 1] = 0;
- }
-
- /*
- * Check that the versions match. In future this might accept
- * several versions and set appropriate flags to handle them.
- */
- if (sscanf(buf, "SSH-%d.%d-%[^\n]\n", &remote_major, &remote_minor,
- remote_version) != 3) {
- char *s = "Protocol mismatch.\n";
-
- (void) atomicio(write, sock_out, s, strlen(s));
- close(sock_in);
- close(sock_out);
- log("Bad protocol version identification '%.100s' from %s",
- buf, remote_ip);
- fatal_cleanup();
- }
- debug("Client protocol version %d.%d; client software version %.100s",
- remote_major, remote_minor, remote_version);
- if (remote_major != PROTOCOL_MAJOR) {
- char *s = "Protocol major versions differ.\n";
-
- (void) atomicio(write, sock_out, s, strlen(s));
- close(sock_in);
- close(sock_out);
- log("Protocol major versions differ for %s: %d vs. %d",
- remote_ip, PROTOCOL_MAJOR, remote_major);
- fatal_cleanup();
- }
- /* Check that the client has sufficiently high software version. */
- if (remote_major == 1 && remote_minor < 3)
- packet_disconnect("Your ssh version is too old and is no longer supported. Please install a newer version.");
-
- if (remote_major == 1 && remote_minor == 3) {
- /* note that this disables agent-forwarding */
- enable_compat13();
- }
+ sshd_exchange_identification(sock_in, sock_out);
/*
* Check that the connection comes from a privileged port. Rhosts-
* and Rhosts-RSA-Authentication only make sense from priviledged
packet_set_nonblocking();
/* perform the key exchange */
- do_ssh_kex();
-
+ do_ssh1_kex();
/* authenticate user and start session */
do_authentication();
(void) dest_tkt();
#endif /* KRB4 */
- /* Cleanup user's local Xauthority file. */
- if (xauthfile)
- xauthfile_cleanup_proc(NULL);
-
/* The connection has been terminated. */
verbose("Closing connection to %.100s", remote_ip);
* SSH1 key exchange
*/
void
-do_ssh_kex()
+do_ssh1_kex()
{
int i, len;
int plen, slen;
packet_send();
packet_write_wait();
}
-
-
-/*
- * Check if the user is allowed to log in via ssh. If user is listed in
- * DenyUsers or user's primary group is listed in DenyGroups, false will
- * be returned. If AllowUsers isn't empty and user isn't listed there, or
- * if AllowGroups isn't empty and user isn't listed there, false will be
- * returned.
- * If the user's shell is not executable, false will be returned.
- * Otherwise true is returned.
- */
-static int
-allowed_user(struct passwd * pw)
-{
- struct stat st;
- struct group *grp;
- int i;
-#ifdef WITH_AIXAUTHENTICATE
- char *loginmsg;
-#endif /* WITH_AIXAUTHENTICATE */
-
- /* Shouldn't be called if pw is NULL, but better safe than sorry... */
- if (!pw)
- return 0;
-
- /* deny if shell does not exists or is not executable */
- if (stat(pw->pw_shell, &st) != 0)
- return 0;
- if (!((st.st_mode & S_IFREG) && (st.st_mode & (S_IXOTH|S_IXUSR|S_IXGRP))))
- return 0;
-
- /* Return false if user is listed in DenyUsers */
- if (options.num_deny_users > 0) {
- if (!pw->pw_name)
- return 0;
- for (i = 0; i < options.num_deny_users; i++)
- if (match_pattern(pw->pw_name, options.deny_users[i]))
- return 0;
- }
- /* Return false if AllowUsers isn't empty and user isn't listed there */
- if (options.num_allow_users > 0) {
- if (!pw->pw_name)
- return 0;
- for (i = 0; i < options.num_allow_users; i++)
- if (match_pattern(pw->pw_name, options.allow_users[i]))
- break;
- /* i < options.num_allow_users iff we break for loop */
- if (i >= options.num_allow_users)
- return 0;
- }
- /* Get the primary group name if we need it. Return false if it fails */
- if (options.num_deny_groups > 0 || options.num_allow_groups > 0) {
- grp = getgrgid(pw->pw_gid);
- if (!grp)
- return 0;
-
- /* Return false if user's group is listed in DenyGroups */
- if (options.num_deny_groups > 0) {
- if (!grp->gr_name)
- return 0;
- for (i = 0; i < options.num_deny_groups; i++)
- if (match_pattern(grp->gr_name, options.deny_groups[i]))
- return 0;
- }
- /*
- * Return false if AllowGroups isn't empty and user's group
- * isn't listed there
- */
- if (options.num_allow_groups > 0) {
- if (!grp->gr_name)
- return 0;
- for (i = 0; i < options.num_allow_groups; i++)
- if (match_pattern(grp->gr_name, options.allow_groups[i]))
- break;
- /* i < options.num_allow_groups iff we break for
- loop */
- if (i >= options.num_allow_groups)
- return 0;
- }
- }
-
-#ifdef WITH_AIXAUTHENTICATE
- if (loginrestrictions(pw->pw_name,S_LOGIN,NULL,&loginmsg) != 0)
- return 0;
-#endif /* WITH_AIXAUTHENTICATE */
-
- /* We found no reason not to let this user try to log on... */
- return 1;
-}
-
-/*
- * Performs authentication of an incoming connection. Session key has already
- * been exchanged and encryption is enabled.
- */
-void
-do_authentication()
-{
- struct passwd *pw, pwcopy;
- int plen;
- unsigned int ulen;
- char *user;
-
- /* Get the name of the user that we wish to log in as. */
- packet_read_expect(&plen, SSH_CMSG_USER);
-
- /* Get the user name. */
- user = packet_get_string(&ulen);
- packet_integrity_check(plen, (4 + ulen), SSH_CMSG_USER);
-
- setproctitle("%s", user);
-
-#ifdef WITH_AIXAUTHENTICATE
- char *loginmsg;
-#endif /* WITH_AIXAUTHENTICATE */
-
-#ifdef AFS
- /* If machine has AFS, set process authentication group. */
- if (k_hasafs()) {
- k_setpag();
- k_unlog();
- }
-#endif /* AFS */
-
- /* Verify that the user is a valid user. */
- pw = getpwnam(user);
- if (!pw || !allowed_user(pw))
- do_fake_authloop(user);
- xfree(user);
-
- /* Take a copy of the returned structure. */
- memset(&pwcopy, 0, sizeof(pwcopy));
- pwcopy.pw_name = xstrdup(pw->pw_name);
- pwcopy.pw_passwd = xstrdup(pw->pw_passwd);
- pwcopy.pw_uid = pw->pw_uid;
- pwcopy.pw_gid = pw->pw_gid;
- pwcopy.pw_dir = xstrdup(pw->pw_dir);
- pwcopy.pw_shell = xstrdup(pw->pw_shell);
- pw = &pwcopy;
-
-#ifdef USE_PAM
- start_pam(pw);
-#endif
-
- /*
- * If we are not running as root, the user must have the same uid as
- * the server.
- */
- if (getuid() != 0 && pw->pw_uid != getuid())
- packet_disconnect("Cannot change user when server not running as root.");
-
- debug("Attempting authentication for %.100s.", pw->pw_name);
-
- /* If the user has no password, accept authentication immediately. */
- if (options.password_authentication &&
-#ifdef KRB4
- (!options.kerberos_authentication || options.kerberos_or_local_passwd) &&
-#endif /* KRB4 */
-#ifdef USE_PAM
- auth_pam_password(pw, "")) {
-#else /* USE_PAM */
- auth_password(pw, "")) {
-#endif /* USE_PAM */
- /* Authentication with empty password succeeded. */
- log("Login for user %s from %.100s, accepted without authentication.",
- pw->pw_name, get_remote_ipaddr());
- } else {
- /* Loop until the user has been authenticated or the
- connection is closed, do_authloop() returns only if
- authentication is successfull */
- do_authloop(pw);
- }
-
- /* The user has been authenticated and accepted. */
-#ifdef WITH_AIXAUTHENTICATE
- loginsuccess(user,get_canonical_hostname(),"ssh",&loginmsg);
-#endif /* WITH_AIXAUTHENTICATE */
- packet_start(SSH_SMSG_SUCCESS);
- packet_send();
- packet_write_wait();
-
- /* Perform session preparation. */
- do_authenticated(pw);
-}
-
-#define AUTH_FAIL_MAX 6
-#define AUTH_FAIL_LOG (AUTH_FAIL_MAX/2)
-#define AUTH_FAIL_MSG "Too many authentication failures for %.100s"
-
-/*
- * read packets and try to authenticate local user *pw.
- * return if authentication is successfull
- */
-void
-do_authloop(struct passwd * pw)
-{
- int attempt = 0;
- unsigned int bits;
- RSA *client_host_key;
- BIGNUM *n;
- char *client_user = NULL, *password = NULL;
- char user[1024];
- unsigned int dlen;
- int plen, nlen, elen;
- unsigned int ulen;
- int type = 0;
- void (*authlog) (const char *fmt,...) = verbose;
-
- /* Indicate that authentication is needed. */
- packet_start(SSH_SMSG_FAILURE);
- packet_send();
- packet_write_wait();
-
- for (attempt = 1;; attempt++) {
- int authenticated = 0;
- strlcpy(user, "", sizeof user);
-
- /* Get a packet from the client. */
- type = packet_read(&plen);
-
- /* Process the packet. */
- switch (type) {
-#ifdef AFS
- case SSH_CMSG_HAVE_KERBEROS_TGT:
- if (!options.kerberos_tgt_passing) {
- /* packet_get_all(); */
- verbose("Kerberos tgt passing disabled.");
- break;
- } else {
- /* Accept Kerberos tgt. */
- char *tgt = packet_get_string(&dlen);
- packet_integrity_check(plen, 4 + dlen, type);
- if (!auth_kerberos_tgt(pw, tgt))
- verbose("Kerberos tgt REFUSED for %s", pw->pw_name);
- xfree(tgt);
- }
- continue;
-
- case SSH_CMSG_HAVE_AFS_TOKEN:
- if (!options.afs_token_passing || !k_hasafs()) {
- /* packet_get_all(); */
- verbose("AFS token passing disabled.");
- break;
- } else {
- /* Accept AFS token. */
- char *token_string = packet_get_string(&dlen);
- packet_integrity_check(plen, 4 + dlen, type);
- if (!auth_afs_token(pw, token_string))
- verbose("AFS token REFUSED for %s", pw->pw_name);
- xfree(token_string);
- }
- continue;
-#endif /* AFS */
-#ifdef KRB4
- case SSH_CMSG_AUTH_KERBEROS:
- if (!options.kerberos_authentication) {
- /* packet_get_all(); */
- verbose("Kerberos authentication disabled.");
- break;
- } else {
- /* Try Kerberos v4 authentication. */
- KTEXT_ST auth;
- char *tkt_user = NULL;
- char *kdata = packet_get_string((unsigned int *) &auth.length);
- packet_integrity_check(plen, 4 + auth.length, type);
-
- if (auth.length < MAX_KTXT_LEN)
- memcpy(auth.dat, kdata, auth.length);
- xfree(kdata);
-
- authenticated = auth_krb4(pw->pw_name, &auth, &tkt_user);
-
- if (authenticated) {
- snprintf(user, sizeof user, " tktuser %s", tkt_user);
- xfree(tkt_user);
- }
- }
- break;
-#endif /* KRB4 */
-
- case SSH_CMSG_AUTH_RHOSTS:
- if (!options.rhosts_authentication) {
- verbose("Rhosts authentication disabled.");
- break;
- }
- /*
- * Get client user name. Note that we just have to
- * trust the client; this is one reason why rhosts
- * authentication is insecure. (Another is
- * IP-spoofing on a local network.)
- */
- client_user = packet_get_string(&ulen);
- packet_integrity_check(plen, 4 + ulen, type);
-
- /* Try to authenticate using /etc/hosts.equiv and
- .rhosts. */
- authenticated = auth_rhosts(pw, client_user);
-
- snprintf(user, sizeof user, " ruser %s", client_user);
- break;
-
- case SSH_CMSG_AUTH_RHOSTS_RSA:
- if (!options.rhosts_rsa_authentication) {
- verbose("Rhosts with RSA authentication disabled.");
- break;
- }
- /*
- * Get client user name. Note that we just have to
- * trust the client; root on the client machine can
- * claim to be any user.
- */
- client_user = packet_get_string(&ulen);
-
- /* Get the client host key. */
- client_host_key = RSA_new();
- if (client_host_key == NULL)
- fatal("RSA_new failed");
- client_host_key->e = BN_new();
- client_host_key->n = BN_new();
- if (client_host_key->e == NULL || client_host_key->n == NULL)
- fatal("BN_new failed");
- bits = packet_get_int();
- packet_get_bignum(client_host_key->e, &elen);
- packet_get_bignum(client_host_key->n, &nlen);
-
- if (bits != BN_num_bits(client_host_key->n))
- error("Warning: keysize mismatch for client_host_key: "
- "actual %d, announced %d", BN_num_bits(client_host_key->n), bits);
- packet_integrity_check(plen, (4 + ulen) + 4 + elen + nlen, type);
-
- authenticated = auth_rhosts_rsa(pw, client_user, client_host_key);
- RSA_free(client_host_key);
-
- snprintf(user, sizeof user, " ruser %s", client_user);
- break;
-
- case SSH_CMSG_AUTH_RSA:
- if (!options.rsa_authentication) {
- verbose("RSA authentication disabled.");
- break;
- }
- /* RSA authentication requested. */
- n = BN_new();
- packet_get_bignum(n, &nlen);
- packet_integrity_check(plen, nlen, type);
- authenticated = auth_rsa(pw, n);
- BN_clear_free(n);
- break;
-
- case SSH_CMSG_AUTH_PASSWORD:
- if (!options.password_authentication) {
- verbose("Password authentication disabled.");
- break;
- }
- /*
- * Read user password. It is in plain text, but was
- * transmitted over the encrypted channel so it is
- * not visible to an outside observer.
- */
- password = packet_get_string(&dlen);
- packet_integrity_check(plen, 4 + dlen, type);
-
-#ifdef USE_PAM
- /* Do PAM auth with password */
- authenticated = auth_pam_password(pw, password);
-#else /* USE_PAM */
- /* Try authentication with the password. */
- authenticated = auth_password(pw, password);
-#endif /* USE_PAM */
- memset(password, 0, strlen(password));
- xfree(password);
- break;
-
-#ifdef SKEY
- case SSH_CMSG_AUTH_TIS:
- debug("rcvd SSH_CMSG_AUTH_TIS");
- if (options.skey_authentication == 1) {
- char *skeyinfo = skey_keyinfo(pw->pw_name);
- if (skeyinfo == NULL) {
- debug("generating fake skeyinfo for %.100s.", pw->pw_name);
- skeyinfo = skey_fake_keyinfo(pw->pw_name);
- }
- if (skeyinfo != NULL) {
- /* we send our s/key- in tis-challenge messages */
- debug("sending challenge '%s'", skeyinfo);
- packet_start(SSH_SMSG_AUTH_TIS_CHALLENGE);
- packet_put_string(skeyinfo, strlen(skeyinfo));
- packet_send();
- packet_write_wait();
- continue;
- }
- }
- break;
- case SSH_CMSG_AUTH_TIS_RESPONSE:
- debug("rcvd SSH_CMSG_AUTH_TIS_RESPONSE");
- if (options.skey_authentication == 1) {
- char *response = packet_get_string(&dlen);
- debug("skey response == '%s'", response);
- packet_integrity_check(plen, 4 + dlen, type);
- authenticated = (skey_haskey(pw->pw_name) == 0 &&
- skey_passcheck(pw->pw_name, response) != -1);
- xfree(response);
- }
- break;
-#else
- case SSH_CMSG_AUTH_TIS:
- /* TIS Authentication is unsupported */
- log("TIS authentication unsupported.");
- break;
-#endif
-
- default:
- /*
- * Any unknown messages will be ignored (and failure
- * returned) during authentication.
- */
- log("Unknown message during authentication: type %d", type);
- break;
- }
-
- /*
- * Check if the user is logging in as root and root logins
- * are disallowed.
- * Note that root login is allowed for forced commands.
- */
- if (authenticated && pw->pw_uid == 0 && !options.permit_root_login) {
- if (forced_command) {
- log("Root login accepted for forced command.");
- } else {
- authenticated = 0;
- log("ROOT LOGIN REFUSED FROM %.200s",
- get_canonical_hostname());
- }
- }
-
- /* Raise logging level */
- if (authenticated ||
- attempt == AUTH_FAIL_LOG ||
- type == SSH_CMSG_AUTH_PASSWORD)
- authlog = log;
-
- authlog("%s %s for %.200s from %.200s port %d%s",
- authenticated ? "Accepted" : "Failed",
- get_authname(type),
- pw->pw_uid == 0 ? "ROOT" : pw->pw_name,
- get_remote_ipaddr(),
- get_remote_port(),
- user);
-
-#ifdef USE_PAM
- if (authenticated) {
- if (!do_pam_account(pw->pw_name, client_user)) {
- if (client_user != NULL) {
- xfree(client_user);
- client_user = NULL;
- }
- do_fake_authloop(pw->pw_name);
- }
- return;
- }
-#else /* USE_PAM */
- if (authenticated) {
- return;
- }
-#endif /* USE_PAM */
-
- if (client_user != NULL) {
- xfree(client_user);
- client_user = NULL;
- }
-
- if (attempt > AUTH_FAIL_MAX)
- packet_disconnect(AUTH_FAIL_MSG, pw->pw_name);
-
- /* Send a message indicating that the authentication attempt failed. */
- packet_start(SSH_SMSG_FAILURE);
- packet_send();
- packet_write_wait();
- }
-}
-
-/*
- * The user does not exist or access is denied,
- * but fake indication that authentication is needed.
- */
-void
-do_fake_authloop(char *user)
-{
- int attempt = 0;
-
- log("Faking authloop for illegal user %.200s from %.200s port %d",
- user,
- get_remote_ipaddr(),
- get_remote_port());
-
- /* Indicate that authentication is needed. */
- packet_start(SSH_SMSG_FAILURE);
- packet_send();
- packet_write_wait();
-
- /*
- * Keep reading packets, and always respond with a failure. This is
- * to avoid disclosing whether such a user really exists.
- */
- for (attempt = 1;; attempt++) {
- /* Read a packet. This will not return if the client disconnects. */
- int plen;
-#ifndef SKEY
- (void)packet_read(&plen);
-#else /* SKEY */
- int type = packet_read(&plen);
- unsigned int dlen;
- char *password, *skeyinfo;
- /* Try to send a fake s/key challenge. */
- if (options.skey_authentication == 1 &&
- (skeyinfo = skey_fake_keyinfo(user)) != NULL) {
- password = NULL;
- if (type == SSH_CMSG_AUTH_TIS) {
- packet_start(SSH_SMSG_AUTH_TIS_CHALLENGE);
- packet_put_string(skeyinfo, strlen(skeyinfo));
- packet_send();
- packet_write_wait();
- continue;
- } else if (type == SSH_CMSG_AUTH_PASSWORD &&
- options.password_authentication &&
- (password = packet_get_string(&dlen)) != NULL &&
- dlen == 5 &&
- strncasecmp(password, "s/key", 5) == 0 ) {
- packet_send_debug(skeyinfo);
- }
- if (password != NULL)
- xfree(password);
- }
-#endif
- if (attempt > AUTH_FAIL_MAX)
- packet_disconnect(AUTH_FAIL_MSG, user);
-
- /*
- * Send failure. This should be indistinguishable from a
- * failed authentication.
- */
- packet_start(SSH_SMSG_FAILURE);
- packet_send();
- packet_write_wait();
-#ifdef WITH_AIXAUTHENTICATE
- if (strncmp(get_authname(type),"password",
- strlen(get_authname(type))) == 0)
- loginfailed(pw->pw_name,get_canonical_hostname(),"ssh");
-#endif /* WITH_AIXAUTHENTICATE */
- }
- /* NOTREACHED */
- abort();
-}
-
-struct pty_cleanup_context {
- const char *ttyname;
- int pid;
-};
-
-/*
- * Function to perform cleanup if we get aborted abnormally (e.g., due to a
- * dropped connection).
- */
-void
-pty_cleanup_proc(void *context)
-{
- struct pty_cleanup_context *cu = context;
-
- debug("pty_cleanup_proc called");
-
- /* Record that the user has logged out. */
- record_logout(cu->pid, cu->ttyname);
-
- /* Release the pseudo-tty. */
- pty_release(cu->ttyname);
-}
-
-/* simple cleanup: chown tty slave back to root */
-static void
-pty_release_proc(void *tty)
-{
- char *ttyname = tty;
- pty_release(ttyname);
-}
-
-/*
- * Prepares for an interactive session. This is called after the user has
- * been successfully authenticated. During this message exchange, pseudo
- * terminals are allocated, X11, TCP/IP, and authentication agent forwardings
- * are requested, etc.
- */
-void
-do_authenticated(struct passwd * pw)
-{
- int type;
- int compression_level = 0, enable_compression_after_reply = 0;
- int have_pty = 0, ptyfd = -1, ttyfd = -1;
- int row, col, xpixel, ypixel, screen;
- char ttyname[64];
- char *command, *term = NULL, *display = NULL, *proto = NULL, *data = NULL;
- int plen;
- unsigned int dlen;
- int n_bytes;
-
- /*
- * Cancel the alarm we set to limit the time taken for
- * authentication.
- */
- alarm(0);
-
- /*
- * Inform the channel mechanism that we are the server side and that
- * the client may request to connect to any port at all. (The user
- * could do it anyway, and we wouldn\'t know what is permitted except
- * by the client telling us, so we can equally well trust the client
- * not to request anything bogus.)
- */
- if (!no_port_forwarding_flag)
- channel_permit_all_opens();
-
- /*
- * We stay in this loop until the client requests to execute a shell
- * or a command.
- */
- while (1) {
-
- /* Get a packet from the client. */
- type = packet_read(&plen);
-
- /* Process the packet. */
- switch (type) {
- case SSH_CMSG_REQUEST_COMPRESSION:
- packet_integrity_check(plen, 4, type);
- compression_level = packet_get_int();
- if (compression_level < 1 || compression_level > 9) {
- packet_send_debug("Received illegal compression level %d.",
- compression_level);
- goto fail;
- }
- /* Enable compression after we have responded with SUCCESS. */
- enable_compression_after_reply = 1;
- break;
-
- case SSH_CMSG_REQUEST_PTY:
- if (no_pty_flag) {
- debug("Allocating a pty not permitted for this authentication.");
- goto fail;
- }
- if (have_pty)
- packet_disconnect("Protocol error: you already have a pty.");
-
- debug("Allocating pty.");
-
- /* Allocate a pty and open it. */
- if (!pty_allocate(&ptyfd, &ttyfd, ttyname,
- sizeof(ttyname))) {
- error("Failed to allocate pty.");
- goto fail;
- }
- fatal_add_cleanup(pty_release_proc, (void *)ttyname);
- pty_setowner(pw, ttyname);
-
- /* Get TERM from the packet. Note that the value may be of arbitrary length. */
- term = packet_get_string(&dlen);
- packet_integrity_check(dlen, strlen(term), type);
-
- /* Remaining bytes */
- n_bytes = plen - (4 + dlen + 4 * 4);
-
- if (strcmp(term, "") == 0) {
- xfree(term);
- term = NULL;
- }
-
- /* Get window size from the packet. */
- row = packet_get_int();
- col = packet_get_int();
- xpixel = packet_get_int();
- ypixel = packet_get_int();
- pty_change_window_size(ptyfd, row, col, xpixel, ypixel);
-
- /* Get tty modes from the packet. */
- tty_parse_modes(ttyfd, &n_bytes);
- packet_integrity_check(plen, 4 + dlen + 4 * 4 + n_bytes, type);
-
- /* Indicate that we now have a pty. */
- have_pty = 1;
- break;
-
- case SSH_CMSG_X11_REQUEST_FORWARDING:
- if (!options.x11_forwarding) {
- packet_send_debug("X11 forwarding disabled in server configuration file.");
- goto fail;
- }
-#ifdef XAUTH_PATH
- if (no_x11_forwarding_flag) {
- packet_send_debug("X11 forwarding not permitted for this authentication.");
- goto fail;
- }
- debug("Received request for X11 forwarding with auth spoofing.");
- if (display)
- packet_disconnect("Protocol error: X11 display already set.");
- {
- unsigned int proto_len, data_len;
- proto = packet_get_string(&proto_len);
- data = packet_get_string(&data_len);
- packet_integrity_check(plen, 4 + proto_len + 4 + data_len + 4, type);
- }
- if (packet_get_protocol_flags() & SSH_PROTOFLAG_SCREEN_NUMBER)
- screen = packet_get_int();
- else
- screen = 0;
- display = x11_create_display_inet(screen, options.x11_display_offset);
- if (!display)
- goto fail;
-
- /* Setup to always have a local .Xauthority. */
- xauthfile = xmalloc(MAXPATHLEN);
- strlcpy(xauthfile, "/tmp/ssh-XXXXXXXX", MAXPATHLEN);
- temporarily_use_uid(pw->pw_uid);
- if (mkdtemp(xauthfile) == NULL) {
- restore_uid();
- error("private X11 dir: mkdtemp %s failed: %s",
- xauthfile, strerror(errno));
- xfree(xauthfile);
- xauthfile = NULL;
- goto fail;
- }
- strlcat(xauthfile, "/cookies", MAXPATHLEN);
- open(xauthfile, O_RDWR|O_CREAT|O_EXCL, 0600);
- restore_uid();
- fatal_add_cleanup(xauthfile_cleanup_proc, NULL);
- break;
-#else /* XAUTH_PATH */
- packet_send_debug("No xauth program; cannot forward with spoofing.");
- goto fail;
-#endif /* XAUTH_PATH */
-
- case SSH_CMSG_AGENT_REQUEST_FORWARDING:
- if (no_agent_forwarding_flag || compat13) {
- debug("Authentication agent forwarding not permitted for this authentication.");
- goto fail;
- }
- debug("Received authentication agent forwarding request.");
- auth_input_request_forwarding(pw);
- break;
-
- case SSH_CMSG_PORT_FORWARD_REQUEST:
- if (no_port_forwarding_flag) {
- debug("Port forwarding not permitted for this authentication.");
- goto fail;
- }
- debug("Received TCP/IP port forwarding request.");
- channel_input_port_forward_request(pw->pw_uid == 0);
- break;
-
- case SSH_CMSG_MAX_PACKET_SIZE:
- if (packet_set_maxsize(packet_get_int()) < 0)
- goto fail;
- break;
-
- case SSH_CMSG_EXEC_SHELL:
- /* Set interactive/non-interactive mode. */
- packet_set_interactive(have_pty || display != NULL,
- options.keepalives);
-
- if (forced_command != NULL)
- goto do_forced_command;
- debug("Forking shell.");
- packet_integrity_check(plen, 0, type);
- if (have_pty)
- do_exec_pty(NULL, ptyfd, ttyfd, ttyname, pw, term, display, proto, data);
- else
- do_exec_no_pty(NULL, pw, display, proto, data);
- return;
-
- case SSH_CMSG_EXEC_CMD:
- /* Set interactive/non-interactive mode. */
- packet_set_interactive(have_pty || display != NULL,
- options.keepalives);
-
- if (forced_command != NULL)
- goto do_forced_command;
- /* Get command from the packet. */
- {
- unsigned int dlen;
- command = packet_get_string(&dlen);
- debug("Executing command '%.500s'", command);
- packet_integrity_check(plen, 4 + dlen, type);
- }
- if (have_pty)
- do_exec_pty(command, ptyfd, ttyfd, ttyname, pw, term, display, proto, data);
- else
- do_exec_no_pty(command, pw, display, proto, data);
- xfree(command);
- return;
-
- default:
- /*
- * Any unknown messages in this phase are ignored,
- * and a failure message is returned.
- */
- log("Unknown packet type received after authentication: %d", type);
- goto fail;
- }
-
- /* The request was successfully processed. */
- packet_start(SSH_SMSG_SUCCESS);
- packet_send();
- packet_write_wait();
-
- /* Enable compression now that we have replied if appropriate. */
- if (enable_compression_after_reply) {
- enable_compression_after_reply = 0;
- packet_start_compression(compression_level);
- }
- continue;
-
-fail:
- /* The request failed. */
- packet_start(SSH_SMSG_FAILURE);
- packet_send();
- packet_write_wait();
- continue;
-
-do_forced_command:
- /*
- * There is a forced command specified for this login.
- * Execute it.
- */
- debug("Executing forced command: %.900s", forced_command);
- if (have_pty)
- do_exec_pty(forced_command, ptyfd, ttyfd, ttyname, pw, term, display, proto, data);
- else
- do_exec_no_pty(forced_command, pw, display, proto, data);
- return;
- }
-}
-
-/*
- * This is called to fork and execute a command when we have no tty. This
- * will call do_child from the child, and server_loop from the parent after
- * setting up file descriptors and such.
- */
-void
-do_exec_no_pty(const char *command, struct passwd * pw,
- const char *display, const char *auth_proto,
- const char *auth_data)
-{
- int pid;
-
-#ifdef USE_PIPES
- int pin[2], pout[2], perr[2];
- /* Allocate pipes for communicating with the program. */
- if (pipe(pin) < 0 || pipe(pout) < 0 || pipe(perr) < 0)
- packet_disconnect("Could not create pipes: %.100s",
- strerror(errno));
-#else /* USE_PIPES */
- int inout[2], err[2];
- /* Uses socket pairs to communicate with the program. */
- if (socketpair(AF_UNIX, SOCK_STREAM, 0, inout) < 0 ||
- socketpair(AF_UNIX, SOCK_STREAM, 0, err) < 0)
- packet_disconnect("Could not create socket pairs: %.100s",
- strerror(errno));
-#endif /* USE_PIPES */
-
- setproctitle("%s@notty", pw->pw_name);
-
-#ifdef USE_PAM
- do_pam_setcred();
-#endif /* USE_PAM */
-
- /* Fork the child. */
- if ((pid = fork()) == 0) {
- /* Child. Reinitialize the log since the pid has changed. */
- log_init(av0, options.log_level, options.log_facility, log_stderr);
-
- /*
- * Create a new session and process group since the 4.4BSD
- * setlogin() affects the entire process group.
- */
- if (setsid() < 0)
- error("setsid failed: %.100s", strerror(errno));
-
-#ifdef USE_PIPES
- /*
- * Redirect stdin. We close the parent side of the socket
- * pair, and make the child side the standard input.
- */
- close(pin[1]);
- if (dup2(pin[0], 0) < 0)
- perror("dup2 stdin");
- close(pin[0]);
-
- /* Redirect stdout. */
- close(pout[0]);
- if (dup2(pout[1], 1) < 0)
- perror("dup2 stdout");
- close(pout[1]);
-
- /* Redirect stderr. */
- close(perr[0]);
- if (dup2(perr[1], 2) < 0)
- perror("dup2 stderr");
- close(perr[1]);
-#else /* USE_PIPES */
- /*
- * Redirect stdin, stdout, and stderr. Stdin and stdout will
- * use the same socket, as some programs (particularly rdist)
- * seem to depend on it.
- */
- close(inout[1]);
- close(err[1]);
- if (dup2(inout[0], 0) < 0) /* stdin */
- perror("dup2 stdin");
- if (dup2(inout[0], 1) < 0) /* stdout. Note: same socket as stdin. */
- perror("dup2 stdout");
- if (dup2(err[0], 2) < 0) /* stderr */
- perror("dup2 stderr");
-#endif /* USE_PIPES */
-
- /* Do processing for the child (exec command etc). */
- do_child(command, pw, NULL, display, auth_proto, auth_data, NULL);
- /* NOTREACHED */
- }
- if (pid < 0)
- packet_disconnect("fork failed: %.100s", strerror(errno));
-#ifdef USE_PIPES
- /* We are the parent. Close the child sides of the pipes. */
- close(pin[0]);
- close(pout[1]);
- close(perr[1]);
-
- /* Enter the interactive session. */
- server_loop(pid, pin[1], pout[0], perr[0]);
- /* server_loop has closed pin[1], pout[1], and perr[1]. */
-#else /* USE_PIPES */
- /* We are the parent. Close the child sides of the socket pairs. */
- close(inout[0]);
- close(err[0]);
-
- /*
- * Enter the interactive session. Note: server_loop must be able to
- * handle the case that fdin and fdout are the same.
- */
- server_loop(pid, inout[1], inout[1], err[1]);
- /* server_loop has closed inout[1] and err[1]. */
-#endif /* USE_PIPES */
-}
-
-/*
- * This is called to fork and execute a command when we have a tty. This
- * will call do_child from the child, and server_loop from the parent after
- * setting up file descriptors, controlling tty, updating wtmp, utmp,
- * lastlog, and other such operations.
- */
-void
-do_exec_pty(const char *command, int ptyfd, int ttyfd,
- const char *ttyname, struct passwd * pw, const char *term,
- const char *display, const char *auth_proto,
- const char *auth_data)
-{
- int pid, fdout;
- int ptymaster;
- const char *hostname;
- time_t last_login_time;
- char buf[100], *time_string;
- FILE *f;
- char line[256];
- struct stat st;
- int quiet_login;
- struct sockaddr_storage from;
- socklen_t fromlen;
- struct pty_cleanup_context cleanup_context;
-
- /* Get remote host name. */
- hostname = get_canonical_hostname();
-
- /*
- * Get the time when the user last logged in. Buf will be set to
- * contain the hostname the last login was from.
- */
- if (!options.use_login) {
- last_login_time = get_last_login_time(pw->pw_uid, pw->pw_name,
- buf, sizeof(buf));
- }
- setproctitle("%s@%s", pw->pw_name, strrchr(ttyname, '/') + 1);
-
-#ifdef USE_PAM
- do_pam_session(pw->pw_name, ttyname);
- do_pam_setcred();
-#endif /* USE_PAM */
-
- /* Fork the child. */
- if ((pid = fork()) == 0) {
- pid = getpid();
-
- /* Child. Reinitialize the log because the pid has
- changed. */
- log_init(av0, options.log_level, options.log_facility, log_stderr);
-
- /* Close the master side of the pseudo tty. */
- close(ptyfd);
-
- /* Make the pseudo tty our controlling tty. */
- pty_make_controlling_tty(&ttyfd, ttyname);
-
- /* Redirect stdin from the pseudo tty. */
- if (dup2(ttyfd, fileno(stdin)) < 0)
- error("dup2 stdin failed: %.100s", strerror(errno));
-
- /* Redirect stdout to the pseudo tty. */
- if (dup2(ttyfd, fileno(stdout)) < 0)
- error("dup2 stdin failed: %.100s", strerror(errno));
-
- /* Redirect stderr to the pseudo tty. */
- if (dup2(ttyfd, fileno(stderr)) < 0)
- error("dup2 stdin failed: %.100s", strerror(errno));
-
- /* Close the extra descriptor for the pseudo tty. */
- close(ttyfd);
-
- /*
- * Get IP address of client. This is needed because we want
- * to record where the user logged in from. If the
- * connection is not a socket, let the ip address be 0.0.0.0.
- */
- memset(&from, 0, sizeof(from));
- if (packet_get_connection_in() == packet_get_connection_out()) {
- fromlen = sizeof(from);
- if (getpeername(packet_get_connection_in(),
- (struct sockaddr *) & from, &fromlen) < 0) {
- debug("getpeername: %.100s", strerror(errno));
- fatal_cleanup();
- }
- }
- /* Record that there was a login on that terminal. */
- record_login(pid, ttyname, pw->pw_name, pw->pw_uid, hostname,
- (struct sockaddr *)&from);
-
- /* Check if .hushlogin exists. */
- snprintf(line, sizeof line, "%.200s/.hushlogin", pw->pw_dir);
- quiet_login = stat(line, &st) >= 0;
-
-#ifdef USE_PAM
- if (!quiet_login)
- print_pam_messages();
-#endif /* USE_PAM */
-
- /*
- * If the user has logged in before, display the time of last
- * login. However, don't display anything extra if a command
- * has been specified (so that ssh can be used to execute
- * commands on a remote machine without users knowing they
- * are going to another machine). Login(1) will do this for
- * us as well, so check if login(1) is used
- */
- if (command == NULL && last_login_time != 0 && !quiet_login &&
- !options.use_login) {
- /* Convert the date to a string. */
- time_string = ctime(&last_login_time);
- /* Remove the trailing newline. */
- if (strchr(time_string, '\n'))
- *strchr(time_string, '\n') = 0;
- /* Display the last login time. Host if displayed
- if known. */
- if (strcmp(buf, "") == 0)
- printf("Last login: %s\r\n", time_string);
- else
- printf("Last login: %s from %s\r\n", time_string, buf);
- }
- /*
- * Print /etc/motd unless a command was specified or printing
- * it was disabled in server options or login(1) will be
- * used. Note that some machines appear to print it in
- * /etc/profile or similar.
- */
- if (command == NULL && options.print_motd && !quiet_login &&
- !options.use_login) {
- /* Print /etc/motd if it exists. */
- f = fopen("/etc/motd", "r");
- if (f) {
- while (fgets(line, sizeof(line), f))
- fputs(line, stdout);
- fclose(f);
- }
- }
- /* Do common processing for the child, such as execing the command. */
- do_child(command, pw, term, display, auth_proto, auth_data, ttyname);
- /* NOTREACHED */
- }
- if (pid < 0)
- packet_disconnect("fork failed: %.100s", strerror(errno));
- /* Parent. Close the slave side of the pseudo tty. */
- close(ttyfd);
-
- /*
- * Add a cleanup function to clear the utmp entry and record logout
- * time in case we call fatal() (e.g., the connection gets closed).
- */
- cleanup_context.pid = pid;
- cleanup_context.ttyname = ttyname;
- fatal_add_cleanup(pty_cleanup_proc, (void *) &cleanup_context);
- fatal_remove_cleanup(pty_release_proc, (void *) ttyname);
-
- /*
- * Create another descriptor of the pty master side for use as the
- * standard input. We could use the original descriptor, but this
- * simplifies code in server_loop. The descriptor is bidirectional.
- */
- fdout = dup(ptyfd);
- if (fdout < 0)
- packet_disconnect("dup #1 failed: %.100s", strerror(errno));
-
- /* we keep a reference to the pty master */
- ptymaster = dup(ptyfd);
- if (ptymaster < 0)
- packet_disconnect("dup #2 failed: %.100s", strerror(errno));
-
- /* Enter interactive session. */
- server_loop(pid, ptyfd, fdout, -1);
- /* server_loop _has_ closed ptyfd and fdout. */
-
- /* Cancel the cleanup function. */
- fatal_remove_cleanup(pty_cleanup_proc, (void *) &cleanup_context);
-
- /* Record that the user has logged out. */
- record_logout(pid, ttyname);
-
- /* Release the pseudo-tty. */
- pty_release(ttyname);
-
- /*
- * Close the server side of the socket pairs. We must do this after
- * the pty cleanup, so that another process doesn't get this pty
- * while we're still cleaning up.
- */
- if (close(ptymaster) < 0)
- error("close(ptymaster): %s", strerror(errno));
-}
-
-/*
- * Sets the value of the given variable in the environment. If the variable
- * already exists, its value is overriden.
- */
-void
-child_set_env(char ***envp, unsigned int *envsizep, const char *name,
- const char *value)
-{
- unsigned int i, namelen;
- char **env;
-
- /*
- * Find the slot where the value should be stored. If the variable
- * already exists, we reuse the slot; otherwise we append a new slot
- * at the end of the array, expanding if necessary.
- */
- env = *envp;
- namelen = strlen(name);
- for (i = 0; env[i]; i++)
- if (strncmp(env[i], name, namelen) == 0 && env[i][namelen] == '=')
- break;
- if (env[i]) {
- /* Reuse the slot. */
- xfree(env[i]);
- } else {
- /* New variable. Expand if necessary. */
- if (i >= (*envsizep) - 1) {
- (*envsizep) += 50;
- env = (*envp) = xrealloc(env, (*envsizep) * sizeof(char *));
- }
- /* Need to set the NULL pointer at end of array beyond the new slot. */
- env[i + 1] = NULL;
- }
-
- /* Allocate space and format the variable in the appropriate slot. */
- env[i] = xmalloc(strlen(name) + 1 + strlen(value) + 1);
- snprintf(env[i], strlen(name) + 1 + strlen(value) + 1, "%s=%s", name, value);
-}
-
-/*
- * Reads environment variables from the given file and adds/overrides them
- * into the environment. If the file does not exist, this does nothing.
- * Otherwise, it must consist of empty lines, comments (line starts with '#')
- * and assignments of the form name=value. No other forms are allowed.
- */
-void
-read_environment_file(char ***env, unsigned int *envsize,
- const char *filename)
-{
- FILE *f;
- char buf[4096];
- char *cp, *value;
-
- f = fopen(filename, "r");
- if (!f)
- return;
-
- while (fgets(buf, sizeof(buf), f)) {
- for (cp = buf; *cp == ' ' || *cp == '\t'; cp++)
- ;
- if (!*cp || *cp == '#' || *cp == '\n')
- continue;
- if (strchr(cp, '\n'))
- *strchr(cp, '\n') = '\0';
- value = strchr(cp, '=');
- if (value == NULL) {
- fprintf(stderr, "Bad line in %.100s: %.200s\n", filename, buf);
- continue;
- }
- /* Replace the equals sign by nul, and advance value to the value string. */
- *value = '\0';
- value++;
- child_set_env(env, envsize, cp, value);
- }
- fclose(f);
-}
-
-#ifdef USE_PAM
-/*
- * Sets any environment variables which have been specified by PAM
- */
-void do_pam_environment(char ***env, int *envsize)
-{
- char *equals, var_name[512], var_val[512];
- char **pam_env;
- int i;
-
- if ((pam_env = fetch_pam_environment()) == NULL)
- return;
-
- for(i = 0; pam_env[i] != NULL; i++) {
- if ((equals = strstr(pam_env[i], "=")) == NULL)
- continue;
-
- if (strlen(pam_env[i]) < (sizeof(var_name) - 1))
- {
- memset(var_name, '\0', sizeof(var_name));
- memset(var_val, '\0', sizeof(var_val));
-
- strncpy(var_name, pam_env[i], equals - pam_env[i]);
- strcpy(var_val, equals + 1);
-
- debug("PAM environment: %s=%s", var_name, var_val);
-
- child_set_env(env, envsize, var_name, var_val);
- }
- }
-}
-#endif /* USE_PAM */
-
-/*
- * Performs common processing for the child, such as setting up the
- * environment, closing extra file descriptors, setting the user and group
- * ids, and executing the command or shell.
- */
-void
-do_child(const char *command, struct passwd * pw, const char *term,
- const char *display, const char *auth_proto,
- const char *auth_data, const char *ttyname)
-{
- const char *shell, *cp = NULL;
- char buf[256];
- FILE *f;
- unsigned int envsize, i;
- char **env;
- extern char **environ;
- struct stat st;
- char *argv[10];
-
-#ifndef USE_PAM /* pam_nologin handles this */
- /* Check /etc/nologin. */
- f = fopen("/etc/nologin", "r");
- if (f) {
- /* /etc/nologin exists. Print its contents and exit. */
- while (fgets(buf, sizeof(buf), f))
- fputs(buf, stderr);
- fclose(f);
- if (pw->pw_uid != 0)
- exit(254);
- }
-#endif /* USE_PAM */
-
- /* Set login name in the kernel. */
- if (setlogin(pw->pw_name) < 0)
- error("setlogin failed: %s", strerror(errno));
-
- /* Set uid, gid, and groups. */
- /* Login(1) does this as well, and it needs uid 0 for the "-h"
- switch, so we let login(1) to this for us. */
- if (!options.use_login) {
- if (getuid() == 0 || geteuid() == 0) {
- if (setgid(pw->pw_gid) < 0) {
- perror("setgid");
- exit(1);
- }
- /* Initialize the group list. */
- if (initgroups(pw->pw_name, pw->pw_gid) < 0) {
- perror("initgroups");
- exit(1);
- }
- endgrent();
-
- /* Permanently switch to the desired uid. */
- permanently_set_uid(pw->pw_uid);
- }
- if (getuid() != pw->pw_uid || geteuid() != pw->pw_uid)
- fatal("Failed to set uids to %d.", (int) pw->pw_uid);
- }
- /*
- * Get the shell from the password data. An empty shell field is
- * legal, and means /bin/sh.
- */
- shell = (pw->pw_shell[0] == '\0') ? _PATH_BSHELL : pw->pw_shell;
-
-#ifdef AFS
- /* Try to get AFS tokens for the local cell. */
- if (k_hasafs()) {
- char cell[64];
-
- if (k_afs_cell_of_file(pw->pw_dir, cell, sizeof(cell)) == 0)
- krb_afslog(cell, 0);
-
- krb_afslog(0, 0);
- }
-#endif /* AFS */
-
- /* Initialize the environment. */
- envsize = 100;
- env = xmalloc(envsize * sizeof(char *));
- env[0] = NULL;
-
- if (!options.use_login) {
- /* Set basic environment. */
- child_set_env(&env, &envsize, "USER", pw->pw_name);
- child_set_env(&env, &envsize, "LOGNAME", pw->pw_name);
- child_set_env(&env, &envsize, "HOME", pw->pw_dir);
- child_set_env(&env, &envsize, "PATH", _PATH_STDPATH);
-
- snprintf(buf, sizeof buf, "%.200s/%.50s",
- _PATH_MAILDIR, pw->pw_name);
- child_set_env(&env, &envsize, "MAIL", buf);
-
- /* Normal systems set SHELL by default. */
- child_set_env(&env, &envsize, "SHELL", shell);
- }
- if (getenv("TZ"))
- child_set_env(&env, &envsize, "TZ", getenv("TZ"));
-
- /* Set custom environment options from RSA authentication. */
- while (custom_environment) {
- struct envstring *ce = custom_environment;
- char *s = ce->s;
- int i;
- for (i = 0; s[i] != '=' && s[i]; i++);
- if (s[i] == '=') {
- s[i] = 0;
- child_set_env(&env, &envsize, s, s + i + 1);
- }
- custom_environment = ce->next;
- xfree(ce->s);
- xfree(ce);
- }
-
- snprintf(buf, sizeof buf, "%.50s %d %d",
- get_remote_ipaddr(), get_remote_port(), get_local_port());
- child_set_env(&env, &envsize, "SSH_CLIENT", buf);
-
- if (ttyname)
- child_set_env(&env, &envsize, "SSH_TTY", ttyname);
- if (term)
- child_set_env(&env, &envsize, "TERM", term);
- if (display)
- child_set_env(&env, &envsize, "DISPLAY", display);
-
-#ifdef _AIX
- {
- char *authstate,*krb5cc;
-
- if ((authstate = getenv("AUTHSTATE")) != NULL)
- child_set_env(&env,&envsize,"AUTHSTATE",authstate);
-
- if ((krb5cc = getenv("KRB5CCNAME")) != NULL)
- child_set_env(&env,&envsize,"KRB5CCNAME",krb5cc);
- }
-#endif
-
-#ifdef KRB4
- {
- extern char *ticket;
-
- if (ticket)
- child_set_env(&env, &envsize, "KRBTKFILE", ticket);
- }
-#endif /* KRB4 */
-
-#ifdef USE_PAM
- /* Pull in any environment variables that may have been set by PAM. */
- do_pam_environment(&env, &envsize);
-#endif /* USE_PAM */
-
- if (xauthfile)
- child_set_env(&env, &envsize, "XAUTHORITY", xauthfile);
-
- if (auth_get_socket_name() != NULL)
- child_set_env(&env, &envsize, SSH_AUTHSOCKET_ENV_NAME,
- auth_get_socket_name());
-
- read_environment_file(&env,&envsize,"/etc/environment");
-
- /* read $HOME/.ssh/environment. */
- if (!options.use_login) {
- snprintf(buf, sizeof buf, "%.200s/.ssh/environment", pw->pw_dir);
- read_environment_file(&env, &envsize, buf);
- }
- if (debug_flag) {
- /* dump the environment */
- fprintf(stderr, "Environment:\n");
- for (i = 0; env[i]; i++)
- fprintf(stderr, " %.200s\n", env[i]);
- }
- /*
- * Close the connection descriptors; note that this is the child, and
- * the server will still have the socket open, and it is important
- * that we do not shutdown it. Note that the descriptors cannot be
- * closed before building the environment, as we call
- * get_remote_ipaddr there.
- */
- if (packet_get_connection_in() == packet_get_connection_out())
- close(packet_get_connection_in());
- else {
- close(packet_get_connection_in());
- close(packet_get_connection_out());
- }
- /*
- * Close all descriptors related to channels. They will still remain
- * open in the parent.
- */
- /* XXX better use close-on-exec? -markus */
- channel_close_all();
-
- /*
- * Close any extra file descriptors. Note that there may still be
- * descriptors left by system functions. They will be closed later.
- */
- endpwent();
-
- /*
- * Close any extra open file descriptors so that we don\'t have them
- * hanging around in clients. Note that we want to do this after
- * initgroups, because at least on Solaris 2.3 it leaves file
- * descriptors open.
- */
- for (i = 3; i < 64; i++)
- close(i);
-
- /* Change current directory to the user\'s home directory. */
- if (chdir(pw->pw_dir) < 0)
- fprintf(stderr, "Could not chdir to home directory %s: %s\n",
- pw->pw_dir, strerror(errno));
-
- /*
- * Must take new environment into use so that .ssh/rc, /etc/sshrc and
- * xauth are run in the proper environment.
- */
- environ = env;
-
- /*
- * Run $HOME/.ssh/rc, /etc/sshrc, or xauth (whichever is found first
- * in this order).
- */
- if (!options.use_login) {
- if (stat(SSH_USER_RC, &st) >= 0) {
- if (debug_flag)
- fprintf(stderr, "Running /bin/sh %s\n", SSH_USER_RC);
-
- f = popen("/bin/sh " SSH_USER_RC, "w");
- if (f) {
- if (auth_proto != NULL && auth_data != NULL)
- fprintf(f, "%s %s\n", auth_proto, auth_data);
- pclose(f);
- } else
- fprintf(stderr, "Could not run %s\n", SSH_USER_RC);
- } else if (stat(SSH_SYSTEM_RC, &st) >= 0) {
- if (debug_flag)
- fprintf(stderr, "Running /bin/sh %s\n", SSH_SYSTEM_RC);
-
- f = popen("/bin/sh " SSH_SYSTEM_RC, "w");
- if (f) {
- if (auth_proto != NULL && auth_data != NULL)
- fprintf(f, "%s %s\n", auth_proto, auth_data);
- pclose(f);
- } else
- fprintf(stderr, "Could not run %s\n", SSH_SYSTEM_RC);
- }
-#ifdef XAUTH_PATH
- else {
- /* Add authority data to .Xauthority if appropriate. */
- if (auth_proto != NULL && auth_data != NULL) {
- if (debug_flag)
- fprintf(stderr, "Running %.100s add %.100s %.100s %.100s\n",
- XAUTH_PATH, display, auth_proto, auth_data);
-
- f = popen(XAUTH_PATH " -q -", "w");
- if (f) {
- fprintf(f, "add %s %s %s\n", display, auth_proto, auth_data);
- pclose(f);
- } else
- fprintf(stderr, "Could not run %s -q -\n", XAUTH_PATH);
- }
- }
-#endif /* XAUTH_PATH */
-
- /* Get the last component of the shell name. */
- cp = strrchr(shell, '/');
- if (cp)
- cp++;
- else
- cp = shell;
- }
- /*
- * If we have no command, execute the shell. In this case, the shell
- * name to be passed in argv[0] is preceded by '-' to indicate that
- * this is a login shell.
- */
- if (!command) {
- if (!options.use_login) {
- char buf[256];
-
- /*
- * Check for mail if we have a tty and it was enabled
- * in server options.
- */
- if (ttyname && options.check_mail) {
- char *mailbox;
- struct stat mailstat;
- mailbox = getenv("MAIL");
- if (mailbox != NULL) {
- if (stat(mailbox, &mailstat) != 0 || mailstat.st_size == 0)
- printf("No mail.\n");
- else if (mailstat.st_mtime < mailstat.st_atime)
- printf("You have mail.\n");
- else
- printf("You have new mail.\n");
- }
- }
- /* Start the shell. Set initial character to '-'. */
- buf[0] = '-';
- strncpy(buf + 1, cp, sizeof(buf) - 1);
- buf[sizeof(buf) - 1] = 0;
-
- /* Execute the shell. */
- argv[0] = buf;
- argv[1] = NULL;
- execve(shell, argv, env);
-
- /* Executing the shell failed. */
- perror(shell);
- exit(1);
-
- } else {
- /* Launch login(1). */
-
- execl(LOGIN_PROGRAM, "login", "-h", get_remote_ipaddr(),
- "-p", "-f", "--", pw->pw_name, NULL);
-
- /* Login couldn't be executed, die. */
-
- perror("login");
- exit(1);
- }
- }
- /*
- * Execute the command using the user's shell. This uses the -c
- * option to execute the command.
- */
- argv[0] = (char *) cp;
- argv[1] = "-c";
- argv[2] = (char *) command;
- argv[3] = NULL;
- execve(shell, argv, env);
- perror(shell);
- exit(1);
-}
andersk / openssh.git / commitdiff
