+/* $OpenBSD: sshconnect1.c,v 1.70 2006/11/06 21:25:28 markus Exp $ */
/*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
*/
#include "includes.h"
-RCSID("$OpenBSD: sshconnect1.c,v 1.51 2002/05/23 19:24:30 markus Exp $");
+
+#include <sys/types.h>
+#include <sys/socket.h>
#include <openssl/bn.h>
#include <openssl/md5.h>
-#ifdef KRB4
-#include <krb.h>
-#endif
-#ifdef KRB5
-#include <krb5.h>
-#ifndef HEIMDAL
-#define krb5_get_err_text(context,code) error_message(code)
-#endif /* !HEIMDAL */
-#endif
-#ifdef AFS
-#include <kafs.h>
-#include "radix.h"
-#endif
+#include <stdarg.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <signal.h>
+#include <pwd.h>
+#include "xmalloc.h"
#include "ssh.h"
#include "ssh1.h"
-#include "xmalloc.h"
#include "rsa.h"
#include "buffer.h"
#include "packet.h"
-#include "mpaux.h"
+#include "key.h"
+#include "cipher.h"
+#include "kex.h"
#include "uidswap.h"
#include "log.h"
#include "readconf.h"
-#include "key.h"
#include "authfd.h"
#include "sshconnect.h"
#include "authfile.h"
-#include "readpass.h"
-#include "cipher.h"
+#include "misc.h"
#include "canohost.h"
+#include "hostfile.h"
#include "auth.h"
-#ifdef GSSAPI
-#include "ssh-gss.h"
-#include "bufaux.h"
-
-/*
- * MD5 hash of host and session keys for verification. This is filled
- * in in ssh_login() and then checked in try_gssapi_authentication().
- */
-unsigned char ssh_key_digest[16];
-#endif /* GSSAPI */
-
/* Session id for the current session. */
u_char session_id[16];
u_int supported_authentications = 0;
/* Wait for server's response. */
type = packet_read();
- /* The server sends failure if it doesn\'t like our key or
+ /* The server sends failure if it doesn't like our key or
does not support RSA authentication. */
if (type == SSH_SMSG_FAILURE) {
debug("Server refused our key.");
* although it advertised it supports this. Just
* return a wrong value.
*/
- log("Authentication agent failed to decrypt challenge.");
+ logit("Authentication agent failed to decrypt challenge.");
memset(response, 0, sizeof(response));
}
key_free(key);
/* Compute the response. */
/* The response is MD5 of decrypted challenge plus session id. */
len = BN_num_bytes(challenge);
- if (len <= 0 || len > sizeof(buf))
+ if (len <= 0 || (u_int)len > sizeof(buf))
packet_disconnect(
"respond_to_rsa_challenge: bad challenge length %d", len);
BIGNUM *challenge;
Key *public, *private;
char buf[300], *passphrase, *comment, *authfile;
- int i, type, quit;
+ int i, perm_ok = 1, type, quit;
public = options.identity_keys[idx];
authfile = options.identity_files[idx];
type = packet_read();
/*
- * The server responds with failure if it doesn\'t like our key or
- * doesn\'t support RSA authentication.
+ * The server responds with failure if it doesn't like our key or
+ * doesn't support RSA authentication.
*/
if (type == SSH_SMSG_FAILURE) {
debug("Server refused our key.");
* load the private key. Try first with empty passphrase; if it
* fails, ask for a passphrase.
*/
- if (public->flags && KEY_FLAG_EXT)
+ if (public->flags & KEY_FLAG_EXT)
private = public;
else
- private = key_load_private_type(KEY_RSA1, authfile, "", NULL);
- if (private == NULL && !options.batch_mode) {
+ private = key_load_private_type(KEY_RSA1, authfile, "", NULL,
+ &perm_ok);
+ if (private == NULL && !options.batch_mode && perm_ok) {
snprintf(buf, sizeof(buf),
"Enter passphrase for RSA key '%.100s': ", comment);
for (i = 0; i < options.number_of_password_prompts; i++) {
passphrase = read_passphrase(buf, 0);
if (strcmp(passphrase, "") != 0) {
private = key_load_private_type(KEY_RSA1,
- authfile, passphrase, NULL);
+ authfile, passphrase, NULL, NULL);
quit = 0;
} else {
debug2("no passphrase given, try next key");
xfree(comment);
if (private == NULL) {
- if (!options.batch_mode)
+ if (!options.batch_mode && perm_ok)
error("Bad passphrase.");
/* Send a dummy response packet to avoid protocol error. */
return 0;
}
-#ifdef KRB4
-static int
-try_krb4_authentication(void)
-{
- KTEXT_ST auth; /* Kerberos data */
- char *reply;
- char inst[INST_SZ];
- char *realm;
- CREDENTIALS cred;
- int r, type;
- socklen_t slen;
- Key_schedule schedule;
- u_long checksum, cksum;
- MSG_DAT msg_data;
- struct sockaddr_in local, foreign;
- struct stat st;
-
- /* Don't do anything if we don't have any tickets. */
- if (stat(tkt_string(), &st) < 0)
- return 0;
-
- strlcpy(inst, (char *)krb_get_phost(get_canonical_hostname(1)),
- INST_SZ);
-
- realm = (char *)krb_realmofhost(get_canonical_hostname(1));
- if (!realm) {
- debug("Kerberos v4: no realm for %s", get_canonical_hostname(1));
- return 0;
- }
- /* This can really be anything. */
- checksum = (u_long)getpid();
-
- r = krb_mk_req(&auth, KRB4_SERVICE_NAME, inst, realm, checksum);
- if (r != KSUCCESS) {
- debug("Kerberos v4 krb_mk_req failed: %s", krb_err_txt[r]);
- return 0;
- }
- /* Get session key to decrypt the server's reply with. */
- r = krb_get_cred(KRB4_SERVICE_NAME, inst, realm, &cred);
- if (r != KSUCCESS) {
- debug("get_cred failed: %s", krb_err_txt[r]);
- return 0;
- }
- des_key_sched((des_cblock *) cred.session, schedule);
-
- /* Send authentication info to server. */
- packet_start(SSH_CMSG_AUTH_KERBEROS);
- packet_put_string((char *) auth.dat, auth.length);
- packet_send();
- packet_write_wait();
-
- /* Zero the buffer. */
- (void) memset(auth.dat, 0, MAX_KTXT_LEN);
-
- slen = sizeof(local);
- memset(&local, 0, sizeof(local));
- if (getsockname(packet_get_connection_in(),
- (struct sockaddr *)&local, &slen) < 0)
- debug("getsockname failed: %s", strerror(errno));
-
- slen = sizeof(foreign);
- memset(&foreign, 0, sizeof(foreign));
- if (getpeername(packet_get_connection_in(),
- (struct sockaddr *)&foreign, &slen) < 0) {
- debug("getpeername failed: %s", strerror(errno));
- fatal_cleanup();
- }
- /* Get server reply. */
- type = packet_read();
- switch (type) {
- case SSH_SMSG_FAILURE:
- /* Should really be SSH_SMSG_AUTH_KERBEROS_FAILURE */
- debug("Kerberos v4 authentication failed.");
- return 0;
- break;
-
- case SSH_SMSG_AUTH_KERBEROS_RESPONSE:
- /* SSH_SMSG_AUTH_KERBEROS_SUCCESS */
- debug("Kerberos v4 authentication accepted.");
-
- /* Get server's response. */
- reply = packet_get_string((u_int *) &auth.length);
- if (auth.length >= MAX_KTXT_LEN)
- fatal("Kerberos v4: Malformed response from server");
- memcpy(auth.dat, reply, auth.length);
- xfree(reply);
-
- packet_check_eom();
-
- /*
- * If his response isn't properly encrypted with the session
- * key, and the decrypted checksum fails to match, he's
- * bogus. Bail out.
- */
- r = krb_rd_priv(auth.dat, auth.length, schedule, &cred.session,
- &foreign, &local, &msg_data);
- if (r != KSUCCESS) {
- debug("Kerberos v4 krb_rd_priv failed: %s",
- krb_err_txt[r]);
- packet_disconnect("Kerberos v4 challenge failed!");
- }
- /* Fetch the (incremented) checksum that we supplied in the request. */
- memcpy((char *)&cksum, (char *)msg_data.app_data,
- sizeof(cksum));
- cksum = ntohl(cksum);
-
- /* If it matches, we're golden. */
- if (cksum == checksum + 1) {
- debug("Kerberos v4 challenge successful.");
- return 1;
- } else
- packet_disconnect("Kerberos v4 challenge failed!");
- break;
-
- default:
- packet_disconnect("Protocol error on Kerberos v4 response: %d", type);
- }
- return 0;
-}
-
-#endif /* KRB4 */
-
-#ifdef KRB5
-static int
-try_krb5_authentication(krb5_context *context, krb5_auth_context *auth_context)
-{
- krb5_error_code problem;
- const char *tkfile;
- struct stat buf;
- krb5_ccache ccache = NULL;
- const char *remotehost;
- krb5_data ap;
- int type;
- krb5_ap_rep_enc_part *reply = NULL;
- int ret;
-
- memset(&ap, 0, sizeof(ap));
-
- problem = krb5_init_context(context);
- if (problem) {
- debug("Kerberos v5: krb5_init_context failed");
- ret = 0;
- goto out;
- }
-
- problem = krb5_auth_con_init(*context, auth_context);
- if (problem) {
- debug("Kerberos v5: krb5_auth_con_init failed");
- ret = 0;
- goto out;
- }
-
-#ifndef HEIMDAL
- problem = krb5_auth_con_setflags(*context, *auth_context,
- KRB5_AUTH_CONTEXT_RET_TIME);
- if (problem) {
- debug("Keberos v5: krb5_auth_con_setflags failed");
- ret = 0;
- goto out;
- }
-#endif
-
- tkfile = krb5_cc_default_name(*context);
- if (strncmp(tkfile, "FILE:", 5) == 0)
- tkfile += 5;
-
- if (stat(tkfile, &buf) == 0 && getuid() != buf.st_uid) {
- debug("Kerberos v5: could not get default ccache (permission denied).");
- ret = 0;
- goto out;
- }
-
- problem = krb5_cc_default(*context, &ccache);
- if (problem) {
- debug("Kerberos v5: krb5_cc_default failed: %s",
- krb5_get_err_text(*context, problem));
- ret = 0;
- goto out;
- }
-
- remotehost = get_canonical_hostname(1);
-
- problem = krb5_mk_req(*context, auth_context, AP_OPTS_MUTUAL_REQUIRED,
- "host", remotehost, NULL, ccache, &ap);
- if (problem) {
- debug("Kerberos v5: krb5_mk_req failed: %s",
- krb5_get_err_text(*context, problem));
- ret = 0;
- goto out;
- }
-
- packet_start(SSH_CMSG_AUTH_KERBEROS);
- packet_put_string((char *) ap.data, ap.length);
- packet_send();
- packet_write_wait();
-
- xfree(ap.data);
- ap.length = 0;
-
- type = packet_read();
- switch (type) {
- case SSH_SMSG_FAILURE:
- /* Should really be SSH_SMSG_AUTH_KERBEROS_FAILURE */
- debug("Kerberos v5 authentication failed.");
- ret = 0;
- break;
-
- case SSH_SMSG_AUTH_KERBEROS_RESPONSE:
- /* SSH_SMSG_AUTH_KERBEROS_SUCCESS */
- debug("Kerberos v5 authentication accepted.");
-
- /* Get server's response. */
- ap.data = packet_get_string((unsigned int *) &ap.length);
- packet_check_eom();
- /* XXX je to dobre? */
-
- problem = krb5_rd_rep(*context, *auth_context, &ap, &reply);
- if (problem) {
- ret = 0;
- }
- ret = 1;
- break;
-
- default:
- packet_disconnect("Protocol error on Kerberos v5 response: %d",
- type);
- ret = 0;
- break;
-
- }
-
- out:
- if (ccache != NULL)
- krb5_cc_close(*context, ccache);
- if (reply != NULL)
- krb5_free_ap_rep_enc_part(*context, reply);
- if (ap.length > 0)
-#ifdef HEIMDAL
- krb5_data_free(&ap);
-#else
- krb5_free_data_contents(*context, &ap);
-#endif
-
- return (ret);
-}
-
-static void
-send_krb5_tgt(krb5_context context, krb5_auth_context auth_context)
-{
- int fd, type;
- krb5_error_code problem;
- krb5_data outbuf;
- krb5_ccache ccache = NULL;
- krb5_creds creds;
-#ifdef HEIMDAL
- krb5_kdc_flags flags;
-#else
- int forwardable;
-#endif
- const char *remotehost;
-
- memset(&creds, 0, sizeof(creds));
- memset(&outbuf, 0, sizeof(outbuf));
-
- fd = packet_get_connection_in();
-
-#ifdef HEIMDAL
- problem = krb5_auth_con_setaddrs_from_fd(context, auth_context, &fd);
-#else
- problem = krb5_auth_con_genaddrs(context, auth_context, fd,
- KRB5_AUTH_CONTEXT_GENERATE_REMOTE_FULL_ADDR |
- KRB5_AUTH_CONTEXT_GENERATE_LOCAL_FULL_ADDR);
-#endif
- if (problem)
- goto out;
-
- problem = krb5_cc_default(context, &ccache);
- if (problem)
- goto out;
-
- problem = krb5_cc_get_principal(context, ccache, &creds.client);
- if (problem)
- goto out;
-
- remotehost = get_canonical_hostname(1);
-
-#ifdef HEIMDAL
- problem = krb5_build_principal(context, &creds.server,
- strlen(creds.client->realm), creds.client->realm,
- "krbtgt", creds.client->realm, NULL);
-#else
- problem = krb5_build_principal(context, &creds.server,
- creds.client->realm.length, creds.client->realm.data,
- "host", remotehost, NULL);
-#endif
- if (problem)
- goto out;
-
- creds.times.endtime = 0;
-
-#ifdef HEIMDAL
- flags.i = 0;
- flags.b.forwarded = 1;
- flags.b.forwardable = krb5_config_get_bool(context, NULL,
- "libdefaults", "forwardable", NULL);
- problem = krb5_get_forwarded_creds(context, auth_context,
- ccache, flags.i, remotehost, &creds, &outbuf);
-#else
- forwardable = 1;
- problem = krb5_fwd_tgt_creds(context, auth_context, remotehost,
- creds.client, creds.server, ccache, forwardable, &outbuf);
-#endif
-
- if (problem)
- goto out;
-
- packet_start(SSH_CMSG_HAVE_KERBEROS_TGT);
- packet_put_string((char *)outbuf.data, outbuf.length);
- packet_send();
- packet_write_wait();
-
- type = packet_read();
-
- if (type == SSH_SMSG_SUCCESS) {
- char *pname;
-
- krb5_unparse_name(context, creds.client, &pname);
- debug("Kerberos v5 TGT forwarded (%s).", pname);
- xfree(pname);
- } else
- debug("Kerberos v5 TGT forwarding failed.");
-
- return;
-
- out:
- if (problem)
- debug("Kerberos v5 TGT forwarding failed: %s",
- krb5_get_err_text(context, problem));
- if (creds.client)
- krb5_free_principal(context, creds.client);
- if (creds.server)
- krb5_free_principal(context, creds.server);
- if (ccache)
- krb5_cc_close(context, ccache);
- if (outbuf.data)
- xfree(outbuf.data);
-}
-#endif /* KRB5 */
-
-#ifdef AFS
-static void
-send_krb4_tgt(void)
-{
- CREDENTIALS *creds;
- struct stat st;
- char buffer[4096], pname[ANAME_SZ], pinst[INST_SZ], prealm[REALM_SZ];
- int problem, type;
-
- /* Don't do anything if we don't have any tickets. */
- if (stat(tkt_string(), &st) < 0)
- return;
-
- creds = xmalloc(sizeof(*creds));
-
- problem = krb_get_tf_fullname(TKT_FILE, pname, pinst, prealm);
- if (problem)
- goto out;
-
- problem = krb_get_cred("krbtgt", prealm, prealm, creds);
- if (problem)
- goto out;
-
- if (time(0) > krb_life_to_time(creds->issue_date, creds->lifetime)) {
- problem = RD_AP_EXP;
- goto out;
- }
- creds_to_radix(creds, (u_char *)buffer, sizeof(buffer));
-
- packet_start(SSH_CMSG_HAVE_KERBEROS_TGT);
- packet_put_cstring(buffer);
- packet_send();
- packet_write_wait();
-
- type = packet_read();
-
- if (type == SSH_SMSG_SUCCESS)
- debug("Kerberos v4 TGT forwarded (%s%s%s@%s).",
- creds->pname, creds->pinst[0] ? "." : "",
- creds->pinst, creds->realm);
- else
- debug("Kerberos v4 TGT rejected.");
-
- xfree(creds);
- return;
-
- out:
- debug("Kerberos v4 TGT passing failed: %s", krb_err_txt[problem]);
- xfree(creds);
-}
-
-static void
-send_afs_tokens(void)
-{
- CREDENTIALS creds;
- struct ViceIoctl parms;
- struct ClearToken ct;
- int i, type, len;
- char buf[2048], *p, *server_cell;
- char buffer[8192];
-
- /* Move over ktc_GetToken, here's something leaner. */
- for (i = 0; i < 100; i++) { /* just in case */
- parms.in = (char *) &i;
- parms.in_size = sizeof(i);
- parms.out = buf;
- parms.out_size = sizeof(buf);
- if (k_pioctl(0, VIOCGETTOK, &parms, 0) != 0)
- break;
- p = buf;
-
- /* Get secret token. */
- memcpy(&creds.ticket_st.length, p, sizeof(u_int));
- if (creds.ticket_st.length > MAX_KTXT_LEN)
- break;
- p += sizeof(u_int);
- memcpy(creds.ticket_st.dat, p, creds.ticket_st.length);
- p += creds.ticket_st.length;
-
- /* Get clear token. */
- memcpy(&len, p, sizeof(len));
- if (len != sizeof(struct ClearToken))
- break;
- p += sizeof(len);
- memcpy(&ct, p, len);
- p += len;
- p += sizeof(len); /* primary flag */
- server_cell = p;
-
- /* Flesh out our credentials. */
- strlcpy(creds.service, "afs", sizeof(creds.service));
- creds.instance[0] = '\0';
- strlcpy(creds.realm, server_cell, REALM_SZ);
- memcpy(creds.session, ct.HandShakeKey, DES_KEY_SZ);
- creds.issue_date = ct.BeginTimestamp;
- creds.lifetime = krb_time_to_life(creds.issue_date,
- ct.EndTimestamp);
- creds.kvno = ct.AuthHandle;
- snprintf(creds.pname, sizeof(creds.pname), "AFS ID %d", ct.ViceId);
- creds.pinst[0] = '\0';
-
- /* Encode token, ship it off. */
- if (creds_to_radix(&creds, (u_char *)buffer,
- sizeof(buffer)) <= 0)
- break;
- packet_start(SSH_CMSG_HAVE_AFS_TOKEN);
- packet_put_cstring(buffer);
- packet_send();
- packet_write_wait();
-
- /* Roger, Roger. Clearance, Clarence. What's your vector,
- Victor? */
- type = packet_read();
-
- if (type == SSH_SMSG_FAILURE)
- debug("AFS token for cell %s rejected.", server_cell);
- else if (type != SSH_SMSG_SUCCESS)
- packet_disconnect("Protocol error on AFS token response: %d", type);
- }
-}
-
-#endif /* AFS */
-
/*
* Tries to authenticate with any string-based challenge/response system.
* Note that the client code is not tied to s/key or TIS.
if (i != 0)
error("Permission denied, please try again.");
if (options.cipher == SSH_CIPHER_NONE)
- log("WARNING: Encryption is disabled! "
+ logit("WARNING: Encryption is disabled! "
"Response will be transmitted in clear text.");
response = read_passphrase(prompt, 0);
if (strcmp(response, "") == 0) {
debug("Doing password authentication.");
if (options.cipher == SSH_CIPHER_NONE)
- log("WARNING: Encryption is disabled! Password will be transmitted in clear text.");
+ logit("WARNING: Encryption is disabled! Password will be transmitted in clear text.");
for (i = 0; i < options.number_of_password_prompts; i++) {
if (i != 0)
error("Permission denied, please try again.");
return 0;
}
-#ifdef GSSAPI
-/*
- * This code stolen from the gss-client.c sample program from MIT's
- * kerberos 5 distribution.
- */
-
-static void display_status_1(m, code, type)
- char *m;
- OM_uint32 code;
- int type;
-{
- OM_uint32 maj_stat, min_stat;
- gss_buffer_desc msg;
- OM_uint32 msg_ctx;
-
- msg_ctx = 0;
- while (1) {
- maj_stat = gss_display_status(&min_stat, code,
- type, GSS_C_NULL_OID,
- &msg_ctx, &msg);
- debug("GSS-API error %s: %s", m, (char *)msg.value);
- (void) gss_release_buffer(&min_stat, &msg);
-
- if (!msg_ctx)
- break;
- }
-}
-
-static void display_gssapi_status(msg, maj_stat, min_stat)
- char *msg;
- OM_uint32 maj_stat;
- OM_uint32 min_stat;
-{
- display_status_1(msg, maj_stat, GSS_C_GSS_CODE);
- display_status_1(msg, min_stat, GSS_C_MECH_CODE);
-}
-
-#ifdef GSI
-char * get_gsi_name()
-{
- OM_uint32 maj_stat;
- OM_uint32 min_stat;
- gss_name_t pname = GSS_C_NO_NAME;
- gss_buffer_desc tmpname;
- gss_buffer_t tmpnamed = &tmpname;
- char *retname;
- gss_OID_set oidset;
- gss_cred_id_t gss_cred = GSS_C_NO_CREDENTIAL;
-
- debug("calling gss_acquire_cred");
- gss_create_empty_oid_set(&min_stat,&oidset);
- gss_add_oid_set_member(&min_stat,&supported_mechs[GSI].oid,&oidset);
- maj_stat = gss_acquire_cred(&min_stat,
- GSS_C_NO_NAME,
- GSS_C_INDEFINITE,
- oidset,
- GSS_C_INITIATE,
- &gss_cred,
- NULL,
- NULL);
-
- if (maj_stat != GSS_S_COMPLETE) {
- display_gssapi_status("Failuring acquiring GSSAPI credentials",
- maj_stat, min_stat);
- gss_cred = GSS_C_NO_CREDENTIAL; /* should not be needed */
- return 0;
- }
-
- debug("calling gss_inquire_cred");
- maj_stat = gss_inquire_cred(&min_stat,
- gss_cred,
- &pname,
- NULL,
- NULL,
- NULL);
- if (maj_stat != GSS_S_COMPLETE) {
- return NULL;
- }
-
- maj_stat = gss_display_name(&min_stat,
- pname,
- tmpnamed,
- NULL);
- if (maj_stat != GSS_S_COMPLETE) {
- return NULL;
- }
- debug("gss_display_name finsished");
- retname = (char *)malloc(tmpname.length + 1);
- if (!retname) {
- return NULL;
- }
- memcpy(retname, tmpname.value, tmpname.length);
- retname[tmpname.length] = '\0';
-
- gss_release_name(&min_stat, &pname);
- gss_release_buffer(&min_stat, tmpnamed);
-
- return retname;
-}
-#endif /* GSI */
-
-int try_gssapi_authentication(char *host, Options *options)
-{
- char *service_name = NULL;
- gss_buffer_desc name_tok;
- gss_buffer_desc send_tok;
- gss_buffer_desc recv_tok;
- gss_buffer_desc *token_ptr;
- gss_name_t target_name = NULL;
- gss_ctx_id_t gss_context;
- gss_OID_desc mech_oid;
- gss_OID name_type;
- gss_OID_set gss_mechs, my_mechs;
- int my_mech_num, i, present;
- OM_uint32 maj_stat;
- OM_uint32 min_stat;
- int ret_stat = 0; /* 1 == success */
- OM_uint32 req_flags = 0;
- OM_uint32 ret_flags;
- int type;
- char *xhost;
- unsigned int slen;
- Gssctxt *ctx = NULL;
-
- /* Make a copy of the host name, in case it was returned by a
- * previous call to gethostbyname(). */
- xhost = xstrdup(host);
-
- /* If xhost is the loopback interface, switch it to our
- true local hostname. */
- resolve_localhost(&xhost);
-
- /* Make sure we have the FQHN. Some GSSAPI implementations don't do
- * this for us themselves */
- make_fqhn(&xhost);
-
- /*
- * Default flags
- */
- req_flags |= GSS_C_REPLAY_FLAG;
-
- /* Do mutual authentication */
- req_flags |= GSS_C_MUTUAL_FLAG;
-
- service_name = (char *) xmalloc(strlen("host") +
- strlen(xhost) +
- 2 /* 1 for '@', 1 for NUL */);
-
- sprintf(service_name, "host@%s", xhost);
-
- xfree(xhost);
- xhost = NULL;
-
- name_type = GSS_C_NT_HOSTBASED_SERVICE;
-
- debug("Service name is %s", service_name);
-
- /* Forward credentials? */
-
-#ifdef GSSAPI
- if(options->gss_deleg_creds) {
- debug("Delegating GSSAPI credentials");
- req_flags |= GSS_C_DELEG_FLAG;
- }
-#endif /* GSSAPI */
-
- debug("req_flags = %u", (unsigned int)req_flags);
-
- name_tok.value = service_name;
- name_tok.length = strlen(service_name) + 1;
- maj_stat = gss_import_name(&min_stat, &name_tok,
- name_type, &target_name);
-
- free(service_name);
- service_name = NULL;
-
- if (maj_stat != GSS_S_COMPLETE) {
- display_gssapi_status("importing service name", maj_stat, min_stat);
- goto cleanup;
- }
-
- maj_stat = gss_indicate_mechs(&min_stat, &gss_mechs);
-
- if (maj_stat != GSS_S_COMPLETE) {
- display_gssapi_status("indicating mechs", maj_stat, min_stat);
- goto cleanup;
- }
-
- /* The GSSAPI supports the mechs in gss_mechs, but which ones do
- we have credentials for? We only get one try, so we don't want
- to propose a mechanism we know is going to fail. */
- maj_stat = gss_create_empty_oid_set(&min_stat, &my_mechs);
- for (i=0; supported_mechs[i].name != NULL; i++) {
- maj_stat = gss_test_oid_set_member(&min_stat, &supported_mechs[i].oid,
- gss_mechs, &present);
- if (present) {
- if (!GSS_ERROR(ssh_gssapi_client_ctx(&ctx, &supported_mechs[i].oid,
- host))) {
- maj_stat = gss_add_oid_set_member(&min_stat,
- &supported_mechs[i].oid,
- &my_mechs);
- debug("GSSAPI mechanism %s supported", supported_mechs[i].name);
- } else {
- debug("no credentials for GSSAPI mechanism %s",
- supported_mechs[i].name);
- }
- } else {
- debug("GSSAPI mechanism %s not supported", supported_mechs[i].name);
- }
- }
-
- /*
- * Send over a packet to the daemon, letting it know we're doing
- * GSSAPI and our mech_oid(s).
- */
- debug("Sending mech oid(s) to server");
- packet_start(SSH_CMSG_AUTH_GSSAPI);
- packet_put_int(my_mechs->count); /* Number of mechs we're sending */
-#ifdef GSI
- /* Send GSI before Kerberos, because if GSI fails, we can always fall
- back and try regular Kerberos authentication with our Kerberos cred. */
- maj_stat = gss_test_oid_set_member(&min_stat, &supported_mechs[GSI].oid,
- my_mechs, &present);
- if (present) {
- packet_put_string(supported_mechs[GSI].oid.elements,
- supported_mechs[GSI].oid.length);
- }
-#endif
- for (my_mech_num = 0; my_mech_num < my_mechs->count; my_mech_num++) {
-#ifdef GSI
- /* Skip GSI. We already sent it above. */
- if ((my_mechs->elements[my_mech_num].length ==
- supported_mechs[GSI].oid.length) &&
- memcmp(my_mechs->elements[my_mech_num].elements,
- supported_mechs[GSI].oid.elements,
- my_mechs->elements[my_mech_num].length) == 0) {
- continue;
- }
-#endif
- packet_put_string(my_mechs->elements[my_mech_num].elements,
- my_mechs->elements[my_mech_num].length);
- }
- packet_send();
- packet_write_wait();
-
- /*
- * Get reply from the daemon to see if our mech was acceptable
- */
- type = packet_read();
-
- switch (type) {
- case SSH_SMSG_AUTH_GSSAPI_RESPONSE:
- debug("Server accepted mechanism");
- /* Successful negotiation */
- break;
-
- case SSH_MSG_AUTH_GSSAPI_ABORT:
- debug("Unable to negotiate GSSAPI mechanism type with server");
- packet_get_all();
- goto cleanup;
-
- default:
- packet_disconnect("Protocol error during GSSAPI authentication:"
- " packet type %d received",
- type);
- /* Does not return */
- }
-
- /* Read the mechanism the server returned */
- mech_oid.elements = packet_get_string(&slen);
- mech_oid.length = slen; /* safe typecast */
- packet_get_all();
-
- /*
- * Perform the context-establishement loop.
- *
- * On each pass through the loop, token_ptr points to the token
- * to send to the server (or GSS_C_NO_BUFFER on the first pass).
- * Every generated token is stored in send_tok which is then
- * transmitted to the server; every received token is stored in
- * recv_tok, which token_ptr is then set to, to be processed by
- * the next call to gss_init_sec_context.
- *
- * GSS-API guarantees that send_tok's length will be non-zero
- * if and only if the server is expecting another token from us,
- * and that gss_init_sec_context returns GSS_S_CONTINUE_NEEDED if
- * and only if the server has another token to send us.
- */
-
- token_ptr = GSS_C_NO_BUFFER;
- gss_context = GSS_C_NO_CONTEXT;
-
- do {
- maj_stat =
- gss_init_sec_context(&min_stat,
- GSS_C_NO_CREDENTIAL,
- &gss_context,
- target_name,
- &mech_oid,
- req_flags,
- 0,
- NULL, /* no channel bindings */
- token_ptr,
- NULL, /* ignore mech type */
- &send_tok,
- &ret_flags,
- NULL); /* ignore time_rec */
-
- if (token_ptr != GSS_C_NO_BUFFER)
- (void) gss_release_buffer(&min_stat, &recv_tok);
-
- if (maj_stat != GSS_S_COMPLETE && maj_stat != GSS_S_CONTINUE_NEEDED) {
- display_gssapi_status("initializing context", maj_stat, min_stat);
-
- /* Send an abort message */
- packet_start(SSH_MSG_AUTH_GSSAPI_ABORT);
- packet_send();
- packet_write_wait();
-
- goto cleanup;
- }
-
- if (send_tok.length != 0) {
- debug("Sending authenticaton token...");
- packet_start(SSH_MSG_AUTH_GSSAPI_TOKEN);
- packet_put_string((char *) send_tok.value, send_tok.length);
- packet_send();
- packet_write_wait();
-
- (void) gss_release_buffer(&min_stat, &send_tok);
- }
-
- if (maj_stat == GSS_S_CONTINUE_NEEDED) {
-
- debug("Continue needed. Reading response...");
-
- type = packet_read();
-
- switch(type) {
-
- case SSH_MSG_AUTH_GSSAPI_TOKEN:
- /* This is what we expected */
- break;
-
- case SSH_MSG_AUTH_GSSAPI_ABORT:
- debug("Server aborted GSSAPI authentication.");
- packet_get_all();
- goto cleanup;
-
- default:
- packet_disconnect("Protocol error during GSSAPI authentication:"
- " packet type %d received",
- type);
- /* Does not return */
- }
-
- recv_tok.value = packet_get_string(&slen);
- recv_tok.length=slen; /* safe typecast */
- packet_get_all();
- token_ptr = &recv_tok;
- }
- } while (maj_stat == GSS_S_CONTINUE_NEEDED);
-
- /* Success */
- ret_stat = 1;
-
- debug("GSSAPI authentication successful");
-
- /*
- * Read hash of host and server keys and make sure it
- * matches what we got earlier.
- */
- debug("Reading hash of server and host keys...");
- type = packet_read();
-
- if (type == SSH_MSG_AUTH_GSSAPI_ABORT) {
- debug("Server aborted GSSAPI authentication.");
- packet_get_all();
- ret_stat = 0;
- goto cleanup;
-
- } else if (type == SSH_SMSG_AUTH_GSSAPI_HASH) {
- gss_buffer_desc wrapped_buf;
- gss_buffer_desc unwrapped_buf;
- int conf_state;
- gss_qop_t qop_state;
-
-
- wrapped_buf.value = packet_get_string(&slen);
- wrapped_buf.length=slen; /* safe typecast */
- packet_get_all();
-
- maj_stat = gss_unwrap(&min_stat,
- gss_context,
- &wrapped_buf,
- &unwrapped_buf,
- &conf_state,
- &qop_state);
-
- if (maj_stat != GSS_S_COMPLETE) {
- display_gssapi_status("unwraping SSHD key hash",
- maj_stat, min_stat);
- packet_disconnect("Verification of SSHD keys through GSSAPI-secured channel failed: "
- "Unwrapping of hash failed.");
- }
-
- if (unwrapped_buf.length != sizeof(ssh_key_digest)) {
- packet_disconnect("Verification of SSHD keys through GSSAPI-secured channel failed: "
- "Size of key hashes do not match (%d != %d)!",
- (int)unwrapped_buf.length,
- (int)sizeof(ssh_key_digest));
- }
-
- if (memcmp(ssh_key_digest, unwrapped_buf.value, sizeof(ssh_key_digest)) != 0) {
- packet_disconnect("Verification of SSHD keys through GSSAPI-secured channel failed: "
- "Hashes don't match!");
- }
-
- debug("Verified SSHD keys through GSSAPI-secured channel.");
-
- gss_release_buffer(&min_stat, &unwrapped_buf);
-
- } else {
- packet_disconnect("Protocol error during GSSAPI authentication:"
- "packet type %d received", type);
- /* Does not return */
- }
-
-
- cleanup:
- if (target_name != NULL)
- (void) gss_release_name(&min_stat, &target_name);
-
- return ret_stat;
-}
-
-#endif /* GSSAPI */
-
-
/*
* SSH1 key exchange
*/
u_char cookie[8];
u_int supported_ciphers;
u_int server_flags, client_flags;
- u_int32_t rand = 0;
+ u_int32_t rnd = 0;
debug("Waiting for server public key.");
rbits = BN_num_bits(server_key->rsa->n);
if (bits != rbits) {
- log("Warning: Server lies about size of server public key: "
+ logit("Warning: Server lies about size of server public key: "
"actual size is %d bits vs. announced %d.", rbits, bits);
- log("Warning: This may be due to an old implementation of ssh.");
+ logit("Warning: This may be due to an old implementation of ssh.");
}
/* Get the host key. */
host_key = key_new(KEY_RSA1);
rbits = BN_num_bits(host_key->rsa->n);
if (bits != rbits) {
- log("Warning: Server lies about size of server host key: "
+ logit("Warning: Server lies about size of server host key: "
"actual size is %d bits vs. announced %d.", rbits, bits);
- log("Warning: This may be due to an old implementation of ssh.");
+ logit("Warning: This may be due to an old implementation of ssh.");
}
-#ifdef GSSAPI
- {
- MD5_CTX md5context;
- Buffer buf;
- unsigned char *data;
- unsigned int data_len;
-
- /*
- * Hash the server and host keys. Later we will check them against
- * a hash sent over a secure channel to make sure they are legit.
- */
- debug("Calculating MD5 hash of server and host keys...");
-
- /* Write all the keys to a temporary buffer */
- buffer_init(&buf);
-
- /* Server key */
- buffer_put_bignum(&buf, server_key->rsa->e);
- buffer_put_bignum(&buf, server_key->rsa->n);
-
- /* Host key */
- buffer_put_bignum(&buf, host_key->rsa->e);
- buffer_put_bignum(&buf, host_key->rsa->n);
-
- /* Get the resulting data */
- data = (unsigned char *) buffer_ptr(&buf);
- data_len = buffer_len(&buf);
-
- /* And hash it */
- MD5_Init(&md5context);
- MD5_Update(&md5context, data, data_len);
- MD5_Final(ssh_key_digest, &md5context);
-
- /* Clean up */
- buffer_clear(&buf);
- buffer_free(&buf);
- }
-#endif /* GSSAPI */
-
/* Get protocol flags. */
server_flags = packet_get_int();
packet_set_protocol_flags(server_flags);
client_flags = SSH_PROTOFLAG_SCREEN_NUMBER | SSH_PROTOFLAG_HOST_IN_FWD_OPEN;
- compute_session_id(session_id, cookie, host_key->rsa->n, server_key->rsa->n);
+ derive_ssh1_session_id(host_key->rsa->n, server_key->rsa->n, cookie, session_id);
/* Generate a session key. */
arc4random_stir();
*/
for (i = 0; i < 32; i++) {
if (i % 4 == 0)
- rand = arc4random();
- session_key[i] = rand & 0xff;
- rand >>= 8;
+ rnd = arc4random();
+ session_key[i] = rnd & 0xff;
+ rnd >>= 8;
}
/*
* the first 16 bytes of the session id.
*/
if ((key = BN_new()) == NULL)
- fatal("respond_to_rsa_challenge: BN_new failed");
- BN_set_word(key, 0);
+ fatal("ssh_kex: BN_new failed");
+ if (BN_set_word(key, 0) == 0)
+ fatal("ssh_kex: BN_set_word failed");
for (i = 0; i < SSH_SESSION_KEY_LENGTH; i++) {
- BN_lshift(key, key, 8);
- if (i < 16)
- BN_add_word(key, session_key[i] ^ session_id[i]);
- else
- BN_add_word(key, session_key[i]);
+ if (BN_lshift(key, key, 8) == 0)
+ fatal("ssh_kex: BN_lshift failed");
+ if (i < 16) {
+ if (BN_add_word(key, session_key[i] ^ session_id[i])
+ == 0)
+ fatal("ssh_kex: BN_add_word failed");
+ } else {
+ if (BN_add_word(key, session_key[i]) == 0)
+ fatal("ssh_kex: BN_add_word failed");
+ }
}
/*
if (options.cipher == SSH_CIPHER_NOT_SET) {
if (cipher_mask_ssh1(1) & supported_ciphers & (1 << ssh_cipher_default))
options.cipher = ssh_cipher_default;
- } else if (options.cipher == SSH_CIPHER_ILLEGAL ||
+ } else if (options.cipher == SSH_CIPHER_INVALID ||
!(cipher_mask_ssh1(1) & (1 << options.cipher))) {
- log("No valid SSH1 cipher, using %.100s instead.",
+ logit("No valid SSH1 cipher, using %.100s instead.",
cipher_name(ssh_cipher_default));
options.cipher = ssh_cipher_default;
}
ssh_userauth1(const char *local_user, const char *server_user, char *host,
Sensitive *sensitive)
{
-#ifdef GSSAPI
-#ifdef GSI
- const char *save_server_user = NULL;
-#endif /* GSI */
-#endif /* GSSAPI */
-
-#ifdef KRB5
- krb5_context context = NULL;
- krb5_auth_context auth_context = NULL;
-#endif
int i, type;
if (supported_authentications == 0)
fatal("ssh_userauth1: server supports no auth methods");
-#ifdef GSSAPI
-#ifdef GSI
- /* if no user given, tack on the subject name after the server_user.
- * This will allow us to run gridmap early to get real user
- * This name will start with /C=
- */
- if ((supported_authentications & (1 << SSH_AUTH_GSSAPI)) &&
- options.gss_authentication) {
- char * retname;
- char * newname;
-
-
- save_server_user = server_user;
-
- retname = get_gsi_name();
-
- if (retname) {
- debug("passing gssapi name '%s'", retname);
- if (server_user) {
- newname = (char *) malloc(strlen(retname) + strlen(server_user) + 4);
- if (newname) {
- strcpy(newname, server_user);
- if(options.implicit) {
- strcat(newname,":i:");
- } else {
- strcat(newname,":x:");
- }
- strcat(newname, retname);
- server_user = newname;
- free(retname);
- }
- }
- }
- debug("server_user %s", server_user);
- }
-#endif /* GSI */
-#endif /* GSSAPI */
-
/* Send the name of the user to log in as on the server. */
packet_start(SSH_CMSG_USER);
packet_put_cstring(server_user);
packet_send();
packet_write_wait();
-#if defined(GSI)
- if(save_server_user)
- {
- server_user = save_server_user;
- }
-#endif
/*
* The server should respond with success if no authentication is
* needed (the user has no password). Otherwise the server responds
if (type != SSH_SMSG_FAILURE)
packet_disconnect("Protocol error: got %d in response to SSH_CMSG_USER", type);
-#ifdef GSSAPI
- /* Try GSSAPI authentication */
- if ((supported_authentications & (1 << SSH_AUTH_GSSAPI)) &&
- options.gss_authentication)
- {
- debug("Trying GSSAPI authentication...");
- try_gssapi_authentication(host, &options);
-
- /*
- * XXX Hmmm. Kerberos authentication only reads a packet if it thinks
- * the authentication went OK, but the server seems to always send
- * a packet back. So I'm not sure if I'm missing something or
- * the Kerberos code is broken. - vwelch 1/27/99
- */
-
- type = packet_read();
- if (type == SSH_SMSG_SUCCESS)
- return; /* Successful connection. */
- if (type != SSH_SMSG_FAILURE)
- packet_disconnect("Protocol error: got %d in response to Kerberos auth", type);
-
- debug("GSSAPI authentication failed");
- }
-#endif /* GSSAPI */
-
-#ifdef KRB5
- if ((supported_authentications & (1 << SSH_AUTH_KERBEROS)) &&
- options.kerberos_authentication) {
- debug("Trying Kerberos v5 authentication.");
-
- if (try_krb5_authentication(&context, &auth_context)) {
- type = packet_read();
- if (type == SSH_SMSG_SUCCESS)
- goto success;
- if (type != SSH_SMSG_FAILURE)
- packet_disconnect("Protocol error: got %d in response to Kerberos v5 auth", type);
- }
- }
-#endif /* KRB5 */
-
-#ifdef KRB4
- if ((supported_authentications & (1 << SSH_AUTH_KERBEROS)) &&
- options.kerberos_authentication) {
- debug("Trying Kerberos v4 authentication.");
-
- if (try_krb4_authentication()) {
- type = packet_read();
- if (type == SSH_SMSG_SUCCESS)
- goto success;
- if (type != SSH_SMSG_FAILURE)
- packet_disconnect("Protocol error: got %d in response to Kerberos v4 auth", type);
- }
- }
-#endif /* KRB4 */
-
- /*
- * Use rhosts authentication if running in privileged socket and we
- * do not wish to remain anonymous.
- */
- if ((supported_authentications & (1 << SSH_AUTH_RHOSTS)) &&
- options.rhosts_authentication) {
- debug("Trying rhosts authentication.");
- packet_start(SSH_CMSG_AUTH_RHOSTS);
- packet_put_cstring(local_user);
- packet_send();
- packet_write_wait();
-
- /* The server should respond with success or failure. */
- type = packet_read();
- if (type == SSH_SMSG_SUCCESS)
- goto success;
- if (type != SSH_SMSG_FAILURE)
- packet_disconnect("Protocol error: got %d in response to rhosts auth",
- type);
- }
/*
* Try .rhosts or /etc/hosts.equiv authentication with RSA host
* authentication.
/* NOTREACHED */
success:
-#ifdef KRB5
- /* Try Kerberos v5 TGT passing. */
- if ((supported_authentications & (1 << SSH_PASS_KERBEROS_TGT)) &&
- options.kerberos_tgt_passing && context && auth_context) {
- if (options.cipher == SSH_CIPHER_NONE)
- log("WARNING: Encryption is disabled! Ticket will be transmitted in the clear!");
- send_krb5_tgt(context, auth_context);
- }
- if (auth_context)
- krb5_auth_con_free(context, auth_context);
- if (context)
- krb5_free_context(context);
-#endif
-
-#ifdef AFS
- /* Try Kerberos v4 TGT passing if the server supports it. */
- if ((supported_authentications & (1 << SSH_PASS_KERBEROS_TGT)) &&
- options.kerberos_tgt_passing) {
- if (options.cipher == SSH_CIPHER_NONE)
- log("WARNING: Encryption is disabled! Ticket will be transmitted in the clear!");
- send_krb4_tgt();
- }
- /* Try AFS token passing if the server supports it. */
- if ((supported_authentications & (1 << SSH_PASS_AFS_TOKEN)) &&
- options.afs_token_passing && k_hasafs()) {
- if (options.cipher == SSH_CIPHER_NONE)
- log("WARNING: Encryption is disabled! Token will be transmitted in the clear!");
- send_afs_tokens();
- }
-#endif /* AFS */
-
return; /* need statement after label */
}
andersk / gssapi-openssh.git / blobdiff