+/* $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 1.56 2003/08/28 12:54:34 markus Exp $");
+
+#include <sys/types.h>
+#include <sys/socket.h>
#include <openssl/bn.h>
#include <openssl/md5.h>
+#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.");
/* 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.");
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 GSSAPI
-#ifdef GSI
-static gss_OID_desc gsioid={9, "\x2B\x06\x01\x04\x01\x9B\x50\x01\x01"};
-char * get_gsi_name()
-{
- gss_name_t pname = GSS_C_NO_NAME;
- gss_buffer_desc tmpname;
- gss_buffer_t tmpnamed = &tmpname;
- char *retname=NULL;
- gss_OID_set oidset;
- gss_cred_id_t gss_cred = GSS_C_NO_CREDENTIAL;
- Gssctxt *ctx = NULL;
-
- ssh_gssapi_build_ctx(&ctx);
-
- gss_create_empty_oid_set(&ctx->minor,&oidset);
- gss_add_oid_set_member(&ctx->minor,&gsioid,&oidset);
- ssh_gssapi_set_oid(ctx,&gsioid);
- ctx->major = gss_acquire_cred(&ctx->minor,
- GSS_C_NO_NAME,
- GSS_C_INDEFINITE,
- oidset,
- GSS_C_INITIATE,
- &gss_cred,
- NULL,
- NULL);
-
- if (ctx->major != GSS_S_COMPLETE) {
- goto cleanup;
- }
-
- debug("calling gss_inquire_cred");
- ctx->major = gss_inquire_cred(&ctx->minor,
- gss_cred,
- &pname,
- NULL,
- NULL,
- NULL);
- if (ctx->major != GSS_S_COMPLETE) {
- goto cleanup;
- }
-
- ctx->major = gss_display_name(&ctx->minor,
- pname,
- tmpnamed,
- NULL);
- if (ctx->major != GSS_S_COMPLETE) {
- goto cleanup;
- }
- debug("gss_display_name finsished");
- retname = xmalloc(tmpname.length + 1);
- memcpy(retname, tmpname.value, tmpname.length);
- retname[tmpname.length] = '\0';
-
- gss_release_name(&ctx->minor, &pname);
- gss_release_buffer(&ctx->minor, tmpnamed);
-
- cleanup:
- if (!retname) {
- debug("Failed to set GSI username from credentials");
- ssh_gssapi_error(ctx);
- }
- if (ctx) ssh_gssapi_delete_ctx(&ctx);
- 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;
- 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;
-
- ssh_gssapi_build_ctx(&ctx);
-
- xhost = xstrdup(get_canonical_hostname(1));
- resolve_localhost(&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? */
- if(options->gss_deleg_creds) {
- debug("Delegating GSSAPI credentials");
- req_flags |= GSS_C_DELEG_FLAG;
- }
-
- debug("req_flags = %u", (unsigned int)req_flags);
-
- name_tok.value = service_name;
- name_tok.length = strlen(service_name) + 1;
- ctx->major = gss_import_name(&ctx->minor, &name_tok,
- name_type, &target_name);
-
- free(service_name);
- service_name = NULL;
-
- if (ctx->major != GSS_S_COMPLETE) {
- ssh_gssapi_error(ctx);
- goto cleanup;
- }
-
- ctx->major = gss_indicate_mechs(&ctx->minor, &gss_mechs);
-
- if (ctx->major != GSS_S_COMPLETE) {
- ssh_gssapi_error(ctx);
- 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. */
- ctx->major = gss_create_empty_oid_set(&ctx->minor, &my_mechs);
- for (i=0; i<gss_mechs->count; i++) {
- if (ssh_gssapi_check_mechanism(&(gss_mechs->elements[i]), host)) {
- ctx->major = gss_add_oid_set_member(&ctx->minor,
- &(gss_mechs->elements[i]),
- &my_mechs);
- }
- }
-
- if (my_mechs->count == 0) {
- debug("No GSSAPI mechanisms.");
- goto cleanup;
- }
-
- /*
- * 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
- {
- int present;
- /* Send GSI before Kerberos, because if GSI fails, we can always
- fall back and try regular Kerberos authentication with our
- Kerberos cred. */
- ctx->major = gss_test_oid_set_member(&ctx->minor, &gsioid,
- my_mechs, &present);
- if (present) {
- packet_put_string(gsioid.elements,gsioid.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 ==
- gsioid.length) &&
- memcmp(my_mechs->elements[my_mech_num].elements,
- gsioid.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:
- case SSH_SMSG_FAILURE:
- 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();
-
- ssh_gssapi_set_oid(ctx, &mech_oid);
-
- /*
- * 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 {
- ctx->major =
- gss_init_sec_context(&ctx->minor,
- GSS_C_NO_CREDENTIAL,
- &gss_context,
- target_name,
- ctx->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(&ctx->minor, &recv_tok);
-
- if (ctx->major != GSS_S_COMPLETE && ctx->major != GSS_S_CONTINUE_NEEDED) {
- ssh_gssapi_error(ctx);
-
- /* 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(&ctx->minor, &send_tok);
- }
-
- if (ctx->major == 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:
- case SSH_SMSG_FAILURE:
- 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 (ctx->major == 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 || type == SSH_SMSG_FAILURE) {
- 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();
-
- ctx->major = gss_unwrap(&ctx->minor,
- gss_context,
- &wrapped_buf,
- &unwrapped_buf,
- &conf_state,
- &qop_state);
-
- if (ctx->major != GSS_S_COMPLETE) {
- ssh_gssapi_error(ctx);
- 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(&ctx->minor, &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(&ctx->minor, &target_name);
- if (ctx)
- ssh_gssapi_delete_ctx(&ctx);
-
- 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.");
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))) {
logit("No valid SSH1 cipher, using %.100s instead.",
cipher_name(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 */
-
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)
- {
- char *canonhost;
- int gssapi_succeeded;
- debug("Trying GSSAPI authentication...");
- canonhost = xstrdup(get_canonical_hostname(1));
- resolve_localhost(&canonhost);
- gssapi_succeeded = try_gssapi_authentication(canonhost, &options);
- xfree(canonhost);
- canonhost=NULL;
-
- if (gssapi_succeeded) {
- type = packet_read();
- if (type == SSH_SMSG_SUCCESS)
- goto success;
- if (type != SSH_SMSG_FAILURE)
- packet_disconnect("Protocol error: got %d in response to GSSAPI auth", type);
- }
-
- debug("GSSAPI authentication failed");
- }
-#endif /* GSSAPI */
-
/*
* Try .rhosts or /etc/hosts.equiv authentication with RSA host
* authentication.
andersk / gssapi-openssh.git / blobdiff