blob: 933c223eccef11aab4f6cb7c0774fd8b59f66f7a [file] [log] [blame]
Damien Millereba71ba2000-04-29 23:57:08 +10001/*
2 * Copyright (c) 2000 Markus Friedl. All rights reserved.
3 *
4 * Redistribution and use in source and binary forms, with or without
5 * modification, are permitted provided that the following conditions
6 * are met:
7 * 1. Redistributions of source code must retain the above copyright
8 * notice, this list of conditions and the following disclaimer.
9 * 2. Redistributions in binary form must reproduce the above copyright
10 * notice, this list of conditions and the following disclaimer in the
11 * documentation and/or other materials provided with the distribution.
Damien Millereba71ba2000-04-29 23:57:08 +100012 *
13 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
14 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
15 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
16 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
17 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
18 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
19 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
20 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
21 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
22 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
23 */
24
25#include "includes.h"
Darren Tucker08bbb2f2003-08-26 12:14:05 +100026RCSID("$OpenBSD: sshconnect2.c,v 1.124 2003/08/25 10:33:33 djm Exp $");
Damien Millereba71ba2000-04-29 23:57:08 +100027
Damien Miller9c617692003-05-14 14:31:11 +100028#include "openbsd-compat/sys-queue.h"
29
Damien Millereba71ba2000-04-29 23:57:08 +100030#include "ssh.h"
Ben Lindstrom226cfa02001-01-22 05:34:40 +000031#include "ssh2.h"
Damien Millereba71ba2000-04-29 23:57:08 +100032#include "xmalloc.h"
Damien Millereba71ba2000-04-29 23:57:08 +100033#include "buffer.h"
34#include "packet.h"
Damien Millereba71ba2000-04-29 23:57:08 +100035#include "compat.h"
Damien Millereba71ba2000-04-29 23:57:08 +100036#include "bufaux.h"
Ben Lindstrom226cfa02001-01-22 05:34:40 +000037#include "cipher.h"
Damien Millereba71ba2000-04-29 23:57:08 +100038#include "kex.h"
39#include "myproposal.h"
Damien Millereba71ba2000-04-29 23:57:08 +100040#include "sshconnect.h"
41#include "authfile.h"
Ben Lindstromdf221392001-03-29 00:36:16 +000042#include "dh.h"
Damien Millerad833b32000-08-23 10:46:23 +100043#include "authfd.h"
Ben Lindstrom226cfa02001-01-22 05:34:40 +000044#include "log.h"
45#include "readconf.h"
46#include "readpass.h"
Ben Lindstromb9be60a2001-03-11 01:49:19 +000047#include "match.h"
Ben Lindstrom20d7c7b2001-04-04 01:56:17 +000048#include "dispatch.h"
Ben Lindstrom5eabda32001-04-12 23:34:34 +000049#include "canohost.h"
Ben Lindstrom1bad2562002-06-06 19:57:33 +000050#include "msg.h"
51#include "pathnames.h"
Damien Miller874d77b2000-10-14 16:23:11 +110052
Darren Tucker0efd1552003-08-26 11:49:55 +100053#ifdef GSSAPI
54#include "ssh-gss.h"
55#endif
56
Damien Millereba71ba2000-04-29 23:57:08 +100057/* import */
58extern char *client_version_string;
59extern char *server_version_string;
60extern Options options;
61
62/*
63 * SSH2 key exchange
64 */
65
Ben Lindstrom46c16222000-12-22 01:43:59 +000066u_char *session_id2 = NULL;
Darren Tucker502d3842003-06-28 12:38:01 +100067u_int session_id2_len = 0;
Damien Millereba71ba2000-04-29 23:57:08 +100068
Ben Lindstrom20d7c7b2001-04-04 01:56:17 +000069char *xxx_host;
70struct sockaddr *xxx_hostaddr;
71
Ben Lindstromf28f6342001-04-04 02:03:04 +000072Kex *xxx_kex = NULL;
73
Ben Lindstrombba81212001-06-25 05:01:22 +000074static int
Ben Lindstromd6481ea2001-06-25 04:37:41 +000075verify_host_key_callback(Key *hostkey)
Ben Lindstrom20d7c7b2001-04-04 01:56:17 +000076{
Ben Lindstromd6481ea2001-06-25 04:37:41 +000077 if (verify_host_key(xxx_host, xxx_hostaddr, hostkey) == -1)
Damien Miller59d9fb92001-10-10 15:03:11 +100078 fatal("Host key verification failed.");
Ben Lindstrom20d7c7b2001-04-04 01:56:17 +000079 return 0;
80}
81
Damien Millereba71ba2000-04-29 23:57:08 +100082void
Damien Miller874d77b2000-10-14 16:23:11 +110083ssh_kex2(char *host, struct sockaddr *hostaddr)
84{
Damien Miller874d77b2000-10-14 16:23:11 +110085 Kex *kex;
Ben Lindstrom20d7c7b2001-04-04 01:56:17 +000086
87 xxx_host = host;
88 xxx_hostaddr = hostaddr;
Damien Miller874d77b2000-10-14 16:23:11 +110089
Damien Millere39cacc2000-11-29 12:18:44 +110090 if (options.ciphers == (char *)-1) {
Damien Miller996acd22003-04-09 20:59:48 +100091 logit("No valid ciphers for protocol version 2 given, using defaults.");
Damien Millere39cacc2000-11-29 12:18:44 +110092 options.ciphers = NULL;
Damien Miller874d77b2000-10-14 16:23:11 +110093 }
94 if (options.ciphers != NULL) {
95 myproposal[PROPOSAL_ENC_ALGS_CTOS] =
96 myproposal[PROPOSAL_ENC_ALGS_STOC] = options.ciphers;
97 }
Damien Millera0ff4662001-03-30 10:49:35 +100098 myproposal[PROPOSAL_ENC_ALGS_CTOS] =
99 compat_cipher_proposal(myproposal[PROPOSAL_ENC_ALGS_CTOS]);
100 myproposal[PROPOSAL_ENC_ALGS_STOC] =
101 compat_cipher_proposal(myproposal[PROPOSAL_ENC_ALGS_STOC]);
Damien Miller874d77b2000-10-14 16:23:11 +1100102 if (options.compression) {
Ben Lindstrom06b33aa2001-02-15 03:01:59 +0000103 myproposal[PROPOSAL_COMP_ALGS_CTOS] =
Ben Lindstrom343010a2002-07-04 00:16:25 +0000104 myproposal[PROPOSAL_COMP_ALGS_STOC] = "zlib,none";
Damien Miller874d77b2000-10-14 16:23:11 +1100105 } else {
Ben Lindstrom06b33aa2001-02-15 03:01:59 +0000106 myproposal[PROPOSAL_COMP_ALGS_CTOS] =
Ben Lindstrom343010a2002-07-04 00:16:25 +0000107 myproposal[PROPOSAL_COMP_ALGS_STOC] = "none,zlib";
Damien Miller874d77b2000-10-14 16:23:11 +1100108 }
Ben Lindstrom06b33aa2001-02-15 03:01:59 +0000109 if (options.macs != NULL) {
110 myproposal[PROPOSAL_MAC_ALGS_CTOS] =
111 myproposal[PROPOSAL_MAC_ALGS_STOC] = options.macs;
112 }
Ben Lindstrom982dbbc2001-04-17 18:11:36 +0000113 if (options.hostkeyalgorithms != NULL)
Damien Miller9f0f5c62001-12-21 14:45:46 +1100114 myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] =
Ben Lindstrom982dbbc2001-04-17 18:11:36 +0000115 options.hostkeyalgorithms;
Damien Miller874d77b2000-10-14 16:23:11 +1100116
Damien Millera5539d22003-04-09 20:50:06 +1000117 if (options.rekey_limit)
118 packet_set_rekey_limit(options.rekey_limit);
119
Ben Lindstrom8ac91062001-04-04 17:57:54 +0000120 /* start key exchange */
Ben Lindstrom238abf62001-04-04 17:52:53 +0000121 kex = kex_setup(myproposal);
Damien Miller8e7fb332003-02-24 12:03:03 +1100122 kex->kex[KEX_DH_GRP1_SHA1] = kexdh_client;
123 kex->kex[KEX_DH_GEX_SHA1] = kexgex_client;
Ben Lindstrom20d7c7b2001-04-04 01:56:17 +0000124 kex->client_version_string=client_version_string;
125 kex->server_version_string=server_version_string;
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000126 kex->verify_host_key=&verify_host_key_callback;
Damien Miller874d77b2000-10-14 16:23:11 +1100127
Ben Lindstromf28f6342001-04-04 02:03:04 +0000128 xxx_kex = kex;
129
Ben Lindstrombe2cc432001-04-04 23:46:07 +0000130 dispatch_run(DISPATCH_BLOCK, &kex->done, kex);
Damien Miller874d77b2000-10-14 16:23:11 +1100131
Ben Lindstrom2d90e002001-04-04 02:00:54 +0000132 session_id2 = kex->session_id;
133 session_id2_len = kex->session_id_len;
134
Damien Miller874d77b2000-10-14 16:23:11 +1100135#ifdef DEBUG_KEXDH
136 /* send 1st encrypted/maced/compressed message */
137 packet_start(SSH2_MSG_IGNORE);
138 packet_put_cstring("markus");
139 packet_send();
140 packet_write_wait();
141#endif
Damien Millereba71ba2000-04-29 23:57:08 +1000142}
Damien Millerb1715dc2000-05-30 13:44:51 +1000143
Damien Millereba71ba2000-04-29 23:57:08 +1000144/*
145 * Authenticate user
146 */
Damien Miller62cee002000-09-23 17:15:56 +1100147
148typedef struct Authctxt Authctxt;
149typedef struct Authmethod Authmethod;
Damien Miller280ecfb2003-05-14 13:46:00 +1000150typedef struct identity Identity;
151typedef struct idlist Idlist;
Damien Miller62cee002000-09-23 17:15:56 +1100152
Damien Miller280ecfb2003-05-14 13:46:00 +1000153struct identity {
154 TAILQ_ENTRY(identity) next;
155 AuthenticationConnection *ac; /* set if agent supports key */
156 Key *key; /* public/private key */
157 char *filename; /* comment for agent-only keys */
158 int tried;
159 int isprivate; /* key points to the private key */
160};
161TAILQ_HEAD(idlist, identity);
Damien Miller62cee002000-09-23 17:15:56 +1100162
163struct Authctxt {
164 const char *server_user;
Ben Lindstrom5eabda32001-04-12 23:34:34 +0000165 const char *local_user;
Damien Miller62cee002000-09-23 17:15:56 +1100166 const char *host;
167 const char *service;
Damien Miller62cee002000-09-23 17:15:56 +1100168 Authmethod *method;
Damien Miller874d77b2000-10-14 16:23:11 +1100169 int success;
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000170 char *authlist;
Ben Lindstrom5eabda32001-04-12 23:34:34 +0000171 /* pubkey */
Damien Miller280ecfb2003-05-14 13:46:00 +1000172 Idlist keys;
Ben Lindstrom5eabda32001-04-12 23:34:34 +0000173 AuthenticationConnection *agent;
174 /* hostbased */
Ben Lindstrom1bad2562002-06-06 19:57:33 +0000175 Sensitive *sensitive;
Ben Lindstrom7d199962001-09-12 18:29:00 +0000176 /* kbd-interactive */
177 int info_req_seen;
Darren Tucker0efd1552003-08-26 11:49:55 +1000178 /* generic */
179 void *methoddata;
Damien Miller62cee002000-09-23 17:15:56 +1100180};
181struct Authmethod {
182 char *name; /* string to compare against server's list */
183 int (*userauth)(Authctxt *authctxt);
184 int *enabled; /* flag in option struct that enables method */
185 int *batch_flag; /* flag in option struct that disables method */
186};
187
Damien Miller630d6f42002-01-22 23:17:30 +1100188void input_userauth_success(int, u_int32_t, void *);
189void input_userauth_failure(int, u_int32_t, void *);
190void input_userauth_banner(int, u_int32_t, void *);
191void input_userauth_error(int, u_int32_t, void *);
192void input_userauth_info_req(int, u_int32_t, void *);
193void input_userauth_pk_ok(int, u_int32_t, void *);
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000194void input_userauth_passwd_changereq(int, u_int32_t, void *);
Damien Miller874d77b2000-10-14 16:23:11 +1100195
Ben Lindstrom3c36bb22001-12-06 17:55:26 +0000196int userauth_none(Authctxt *);
197int userauth_pubkey(Authctxt *);
198int userauth_passwd(Authctxt *);
199int userauth_kbdint(Authctxt *);
200int userauth_hostbased(Authctxt *);
Damien Miller3ab496b2003-05-14 13:47:37 +1000201int userauth_kerberos(Authctxt *);
Damien Miller62cee002000-09-23 17:15:56 +1100202
Darren Tucker0efd1552003-08-26 11:49:55 +1000203#ifdef GSSAPI
204int userauth_gssapi(Authctxt *authctxt);
205void input_gssapi_response(int type, u_int32_t, void *);
206void input_gssapi_token(int type, u_int32_t, void *);
207void input_gssapi_hash(int type, u_int32_t, void *);
208void input_gssapi_error(int, u_int32_t, void *);
209void input_gssapi_errtok(int, u_int32_t, void *);
210#endif
211
Ben Lindstrom3c36bb22001-12-06 17:55:26 +0000212void userauth(Authctxt *, char *);
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000213
Damien Miller280ecfb2003-05-14 13:46:00 +1000214static int sign_and_send_pubkey(Authctxt *, Identity *);
Damien Miller280ecfb2003-05-14 13:46:00 +1000215static void pubkey_prepare(Authctxt *);
216static void pubkey_cleanup(Authctxt *);
217static Key *load_identity_file(char *);
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000218
Ben Lindstrombba81212001-06-25 05:01:22 +0000219static Authmethod *authmethod_get(char *authlist);
220static Authmethod *authmethod_lookup(const char *name);
221static char *authmethods_get(void);
Damien Miller62cee002000-09-23 17:15:56 +1100222
223Authmethod authmethods[] = {
Darren Tucker0efd1552003-08-26 11:49:55 +1000224#ifdef GSSAPI
225 {"gssapi",
226 userauth_gssapi,
227 &options.gss_authentication,
228 NULL},
229#endif
Ben Lindstrom1bfe2912001-06-05 19:37:25 +0000230 {"hostbased",
231 userauth_hostbased,
232 &options.hostbased_authentication,
233 NULL},
Ben Lindstrom45350e82001-08-06 20:57:11 +0000234 {"publickey",
235 userauth_pubkey,
236 &options.pubkey_authentication,
237 NULL},
Damien Miller874d77b2000-10-14 16:23:11 +1100238 {"keyboard-interactive",
239 userauth_kbdint,
240 &options.kbd_interactive_authentication,
241 &options.batch_mode},
Ben Lindstrom45350e82001-08-06 20:57:11 +0000242 {"password",
243 userauth_passwd,
244 &options.password_authentication,
245 &options.batch_mode},
Damien Miller874d77b2000-10-14 16:23:11 +1100246 {"none",
247 userauth_none,
248 NULL,
249 NULL},
Damien Miller62cee002000-09-23 17:15:56 +1100250 {NULL, NULL, NULL, NULL}
251};
252
253void
Ben Lindstrom5eabda32001-04-12 23:34:34 +0000254ssh_userauth2(const char *local_user, const char *server_user, char *host,
Ben Lindstrom1bad2562002-06-06 19:57:33 +0000255 Sensitive *sensitive)
Damien Miller62cee002000-09-23 17:15:56 +1100256{
257 Authctxt authctxt;
258 int type;
Damien Miller62cee002000-09-23 17:15:56 +1100259
Ben Lindstrom551ea372001-06-05 18:56:16 +0000260 if (options.challenge_response_authentication)
Ben Lindstrom95fb2dd2001-01-23 03:12:10 +0000261 options.kbd_interactive_authentication = 1;
262
Damien Miller62cee002000-09-23 17:15:56 +1100263 packet_start(SSH2_MSG_SERVICE_REQUEST);
264 packet_put_cstring("ssh-userauth");
265 packet_send();
Ben Lindstrom064496f2002-12-23 02:04:22 +0000266 debug("SSH2_MSG_SERVICE_REQUEST sent");
Damien Miller62cee002000-09-23 17:15:56 +1100267 packet_write_wait();
Damien Millerdff50992002-01-22 23:16:32 +1100268 type = packet_read();
Ben Lindstrom064496f2002-12-23 02:04:22 +0000269 if (type != SSH2_MSG_SERVICE_ACCEPT)
270 fatal("Server denied authentication request: %d", type);
Damien Miller62cee002000-09-23 17:15:56 +1100271 if (packet_remaining() > 0) {
Damien Millerdff50992002-01-22 23:16:32 +1100272 char *reply = packet_get_string(NULL);
Ben Lindstrom064496f2002-12-23 02:04:22 +0000273 debug2("service_accept: %s", reply);
Damien Miller62cee002000-09-23 17:15:56 +1100274 xfree(reply);
Damien Miller62cee002000-09-23 17:15:56 +1100275 } else {
Ben Lindstrom1d568f92002-12-23 02:44:36 +0000276 debug2("buggy server: service_accept w/o service");
Damien Miller62cee002000-09-23 17:15:56 +1100277 }
Damien Miller48b03fc2002-01-22 23:11:40 +1100278 packet_check_eom();
Ben Lindstrom064496f2002-12-23 02:04:22 +0000279 debug("SSH2_MSG_SERVICE_ACCEPT received");
Damien Miller62cee002000-09-23 17:15:56 +1100280
Ben Lindstromb9be60a2001-03-11 01:49:19 +0000281 if (options.preferred_authentications == NULL)
282 options.preferred_authentications = authmethods_get();
283
Damien Miller62cee002000-09-23 17:15:56 +1100284 /* setup authentication context */
Ben Lindstrom7d199962001-09-12 18:29:00 +0000285 memset(&authctxt, 0, sizeof(authctxt));
Damien Miller280ecfb2003-05-14 13:46:00 +1000286 pubkey_prepare(&authctxt);
Damien Miller62cee002000-09-23 17:15:56 +1100287 authctxt.server_user = server_user;
Ben Lindstrom5eabda32001-04-12 23:34:34 +0000288 authctxt.local_user = local_user;
Damien Miller62cee002000-09-23 17:15:56 +1100289 authctxt.host = host;
290 authctxt.service = "ssh-connection"; /* service name */
291 authctxt.success = 0;
Damien Miller874d77b2000-10-14 16:23:11 +1100292 authctxt.method = authmethod_lookup("none");
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000293 authctxt.authlist = NULL;
Darren Tucker0efd1552003-08-26 11:49:55 +1000294 authctxt.methoddata = NULL;
Ben Lindstrom1bad2562002-06-06 19:57:33 +0000295 authctxt.sensitive = sensitive;
Ben Lindstrom7d199962001-09-12 18:29:00 +0000296 authctxt.info_req_seen = 0;
Damien Miller874d77b2000-10-14 16:23:11 +1100297 if (authctxt.method == NULL)
298 fatal("ssh_userauth2: internal error: cannot send userauth none request");
Damien Miller62cee002000-09-23 17:15:56 +1100299
300 /* initial userauth request */
Damien Miller874d77b2000-10-14 16:23:11 +1100301 userauth_none(&authctxt);
Damien Miller62cee002000-09-23 17:15:56 +1100302
Ben Lindstrom8ac91062001-04-04 17:57:54 +0000303 dispatch_init(&input_userauth_error);
Damien Miller62cee002000-09-23 17:15:56 +1100304 dispatch_set(SSH2_MSG_USERAUTH_SUCCESS, &input_userauth_success);
305 dispatch_set(SSH2_MSG_USERAUTH_FAILURE, &input_userauth_failure);
Ben Lindstromd26dcf32001-01-06 15:18:16 +0000306 dispatch_set(SSH2_MSG_USERAUTH_BANNER, &input_userauth_banner);
Damien Miller62cee002000-09-23 17:15:56 +1100307 dispatch_run(DISPATCH_BLOCK, &authctxt.success, &authctxt); /* loop until success */
308
Damien Miller280ecfb2003-05-14 13:46:00 +1000309 pubkey_cleanup(&authctxt);
Damien Millerf842fcb2003-05-15 12:01:28 +1000310 dispatch_range(SSH2_MSG_USERAUTH_MIN, SSH2_MSG_USERAUTH_MAX, NULL);
311
Ben Lindstrom1d568f92002-12-23 02:44:36 +0000312 debug("Authentication succeeded (%s).", authctxt.method->name);
Damien Miller62cee002000-09-23 17:15:56 +1100313}
Damien Millerf842fcb2003-05-15 12:01:28 +1000314
Damien Miller62cee002000-09-23 17:15:56 +1100315void
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000316userauth(Authctxt *authctxt, char *authlist)
317{
Darren Tucker0efd1552003-08-26 11:49:55 +1000318 if (authctxt->methoddata) {
319 xfree(authctxt->methoddata);
320 authctxt->methoddata = NULL;
321 }
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000322 if (authlist == NULL) {
323 authlist = authctxt->authlist;
324 } else {
325 if (authctxt->authlist)
326 xfree(authctxt->authlist);
327 authctxt->authlist = authlist;
328 }
329 for (;;) {
330 Authmethod *method = authmethod_get(authlist);
331 if (method == NULL)
332 fatal("Permission denied (%s).", authlist);
333 authctxt->method = method;
Damien Millerf842fcb2003-05-15 12:01:28 +1000334
335 /* reset the per method handler */
336 dispatch_range(SSH2_MSG_USERAUTH_PER_METHOD_MIN,
337 SSH2_MSG_USERAUTH_PER_METHOD_MAX, NULL);
338
339 /* and try new method */
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000340 if (method->userauth(authctxt) != 0) {
341 debug2("we sent a %s packet, wait for reply", method->name);
342 break;
343 } else {
344 debug2("we did not send a packet, disable method");
345 method->enabled = NULL;
346 }
347 }
348}
Ben Lindstrom5c385522002-06-23 21:23:20 +0000349
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000350void
Damien Miller630d6f42002-01-22 23:17:30 +1100351input_userauth_error(int type, u_int32_t seq, void *ctxt)
Damien Miller62cee002000-09-23 17:15:56 +1100352{
Ben Lindstromd26dcf32001-01-06 15:18:16 +0000353 fatal("input_userauth_error: bad message during authentication: "
354 "type %d", type);
355}
Ben Lindstrom5c385522002-06-23 21:23:20 +0000356
Ben Lindstromd26dcf32001-01-06 15:18:16 +0000357void
Damien Miller630d6f42002-01-22 23:17:30 +1100358input_userauth_banner(int type, u_int32_t seq, void *ctxt)
Ben Lindstromd26dcf32001-01-06 15:18:16 +0000359{
360 char *msg, *lang;
361 debug3("input_userauth_banner");
362 msg = packet_get_string(NULL);
363 lang = packet_get_string(NULL);
Darren Tucker08bbb2f2003-08-26 12:14:05 +1000364 logit("%s", msg);
Ben Lindstromd26dcf32001-01-06 15:18:16 +0000365 xfree(msg);
366 xfree(lang);
Damien Miller62cee002000-09-23 17:15:56 +1100367}
Ben Lindstrom5c385522002-06-23 21:23:20 +0000368
Damien Miller62cee002000-09-23 17:15:56 +1100369void
Damien Miller630d6f42002-01-22 23:17:30 +1100370input_userauth_success(int type, u_int32_t seq, void *ctxt)
Damien Miller62cee002000-09-23 17:15:56 +1100371{
372 Authctxt *authctxt = ctxt;
373 if (authctxt == NULL)
374 fatal("input_userauth_success: no authentication context");
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000375 if (authctxt->authlist)
376 xfree(authctxt->authlist);
Darren Tucker0efd1552003-08-26 11:49:55 +1000377 if (authctxt->methoddata)
378 xfree(authctxt->methoddata);
Damien Miller62cee002000-09-23 17:15:56 +1100379 authctxt->success = 1; /* break out */
380}
Ben Lindstrom5c385522002-06-23 21:23:20 +0000381
Damien Miller62cee002000-09-23 17:15:56 +1100382void
Damien Miller630d6f42002-01-22 23:17:30 +1100383input_userauth_failure(int type, u_int32_t seq, void *ctxt)
Damien Miller62cee002000-09-23 17:15:56 +1100384{
Damien Miller62cee002000-09-23 17:15:56 +1100385 Authctxt *authctxt = ctxt;
386 char *authlist = NULL;
387 int partial;
Damien Miller62cee002000-09-23 17:15:56 +1100388
389 if (authctxt == NULL)
390 fatal("input_userauth_failure: no authentication context");
391
Damien Miller874d77b2000-10-14 16:23:11 +1100392 authlist = packet_get_string(NULL);
Damien Miller62cee002000-09-23 17:15:56 +1100393 partial = packet_get_char();
Damien Miller48b03fc2002-01-22 23:11:40 +1100394 packet_check_eom();
Damien Miller62cee002000-09-23 17:15:56 +1100395
396 if (partial != 0)
Damien Miller996acd22003-04-09 20:59:48 +1000397 logit("Authenticated with partial success.");
Ben Lindstrom1d568f92002-12-23 02:44:36 +0000398 debug("Authentications that can continue: %s", authlist);
Damien Miller62cee002000-09-23 17:15:56 +1100399
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000400 userauth(authctxt, authlist);
401}
402void
Damien Miller630d6f42002-01-22 23:17:30 +1100403input_userauth_pk_ok(int type, u_int32_t seq, void *ctxt)
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000404{
405 Authctxt *authctxt = ctxt;
406 Key *key = NULL;
Damien Miller280ecfb2003-05-14 13:46:00 +1000407 Identity *id = NULL;
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000408 Buffer b;
Ben Lindstrom90fd8142002-02-26 18:09:42 +0000409 int pktype, sent = 0;
410 u_int alen, blen;
411 char *pkalg, *fp;
412 u_char *pkblob;
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000413
414 if (authctxt == NULL)
415 fatal("input_userauth_pk_ok: no authentication context");
416 if (datafellows & SSH_BUG_PKOK) {
417 /* this is similar to SSH_BUG_PKAUTH */
418 debug2("input_userauth_pk_ok: SSH_BUG_PKOK");
419 pkblob = packet_get_string(&blen);
420 buffer_init(&b);
421 buffer_append(&b, pkblob, blen);
422 pkalg = buffer_get_string(&b, &alen);
423 buffer_free(&b);
424 } else {
425 pkalg = packet_get_string(&alen);
426 pkblob = packet_get_string(&blen);
Kevin Stevesef4eea92001-02-05 12:42:17 +0000427 }
Damien Miller48b03fc2002-01-22 23:11:40 +1100428 packet_check_eom();
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000429
Damien Miller280ecfb2003-05-14 13:46:00 +1000430 debug("Server accepts key: pkalg %s blen %u", pkalg, blen);
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000431
Damien Miller280ecfb2003-05-14 13:46:00 +1000432 if ((pktype = key_type_from_name(pkalg)) == KEY_UNSPEC) {
433 debug("unknown pkalg %s", pkalg);
434 goto done;
435 }
436 if ((key = key_from_blob(pkblob, blen)) == NULL) {
437 debug("no key from blob. pkalg %s", pkalg);
438 goto done;
439 }
440 if (key->type != pktype) {
441 error("input_userauth_pk_ok: type mismatch "
442 "for decoded key (received %d, expected %d)",
443 key->type, pktype);
444 goto done;
445 }
446 fp = key_fingerprint(key, SSH_FP_MD5, SSH_FP_HEX);
447 debug2("input_userauth_pk_ok: fp %s", fp);
448 xfree(fp);
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000449
Damien Miller280ecfb2003-05-14 13:46:00 +1000450 TAILQ_FOREACH(id, &authctxt->keys, next) {
451 if (key_equal(key, id->key)) {
452 sent = sign_and_send_pubkey(authctxt, id);
453 break;
454 }
455 }
456done:
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000457 if (key != NULL)
458 key_free(key);
459 xfree(pkalg);
460 xfree(pkblob);
461
Ben Lindstroma962c2f2002-07-04 00:14:17 +0000462 /* try another method if we did not send a packet */
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000463 if (sent == 0)
464 userauth(authctxt, NULL);
Damien Miller62cee002000-09-23 17:15:56 +1100465}
466
Darren Tucker0efd1552003-08-26 11:49:55 +1000467#ifdef GSSAPI
468int
469userauth_gssapi(Authctxt *authctxt)
470{
471 Gssctxt *gssctxt = NULL;
472 static gss_OID_set supported = NULL;
473 static int mech = 0;
474 OM_uint32 min;
475 int ok = 0;
476
477 /* Try one GSSAPI method at a time, rather than sending them all at
478 * once. */
479
480 if (supported == NULL)
481 gss_indicate_mechs(&min, &supported);
482
483 /* Check to see if the mechanism is usable before we offer it */
484 while (mech<supported->count && !ok) {
485 if (gssctxt)
486 ssh_gssapi_delete_ctx(&gssctxt);
487 ssh_gssapi_build_ctx(&gssctxt);
488 ssh_gssapi_set_oid(gssctxt, &supported->elements[mech]);
489
490 /* My DER encoding requires length<128 */
491 if (supported->elements[mech].length < 128 &&
492 !GSS_ERROR(ssh_gssapi_import_name(gssctxt,
493 authctxt->host))) {
494 ok = 1; /* Mechanism works */
495 } else {
496 mech++;
497 }
498 }
499
500 if (!ok) return 0;
501
502 authctxt->methoddata=(void *)gssctxt;
503
504 packet_start(SSH2_MSG_USERAUTH_REQUEST);
505 packet_put_cstring(authctxt->server_user);
506 packet_put_cstring(authctxt->service);
507 packet_put_cstring(authctxt->method->name);
508
509 packet_put_int(1);
510
511 /* Some servers encode the OID incorrectly (as we used to) */
512 if (datafellows & SSH_BUG_GSSAPI_BER) {
513 packet_put_string(supported->elements[mech].elements,
514 supported->elements[mech].length);
515 } else {
516 packet_put_int((supported->elements[mech].length)+2);
517 packet_put_char(SSH_GSS_OIDTYPE);
518 packet_put_char(supported->elements[mech].length);
519 packet_put_raw(supported->elements[mech].elements,
520 supported->elements[mech].length);
521 }
522
523 packet_send();
524
525 dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_RESPONSE, &input_gssapi_response);
526 dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, &input_gssapi_token);
527 dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERROR, &input_gssapi_error);
528 dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK, &input_gssapi_errtok);
529
530 mech++; /* Move along to next candidate */
531
532 return 1;
533}
534
535void
536input_gssapi_response(int type, u_int32_t plen, void *ctxt)
537{
538 Authctxt *authctxt = ctxt;
539 Gssctxt *gssctxt;
540 OM_uint32 status, ms;
541 int oidlen;
542 char *oidv;
543 gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
544
545 if (authctxt == NULL)
546 fatal("input_gssapi_response: no authentication context");
547 gssctxt = authctxt->methoddata;
548
549 /* Setup our OID */
550 oidv = packet_get_string(&oidlen);
551
552 if (datafellows & SSH_BUG_GSSAPI_BER) {
553 if (!ssh_gssapi_check_oid(gssctxt, oidv, oidlen))
554 fatal("Server returned different OID than expected");
555 } else {
556 if(oidv[0] != SSH_GSS_OIDTYPE || oidv[1] != oidlen-2) {
557 debug("Badly encoded mechanism OID received");
558 userauth(authctxt, NULL);
559 xfree(oidv);
560 return;
561 }
562 if (!ssh_gssapi_check_oid(gssctxt, oidv+2, oidlen-2))
563 fatal("Server returned different OID than expected");
564 }
565
566 packet_check_eom();
567
568 xfree(oidv);
569
570 status = ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
571 GSS_C_NO_BUFFER, &send_tok, NULL);
572 if (GSS_ERROR(status)) {
573 if (send_tok.length > 0) {
574 packet_start(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK);
575 packet_put_string(send_tok.value, send_tok.length);
576 packet_send();
577 gss_release_buffer(&ms, &send_tok);
578 }
579 /* Start again with next method on list */
580 debug("Trying to start again");
581 userauth(authctxt, NULL);
582 return;
583 }
584
585 /* We must have data to send */
586 packet_start(SSH2_MSG_USERAUTH_GSSAPI_TOKEN);
587 packet_put_string(send_tok.value, send_tok.length);
588 packet_send();
589 gss_release_buffer(&ms, &send_tok);
590}
591
592void
593input_gssapi_token(int type, u_int32_t plen, void *ctxt)
594{
595 Authctxt *authctxt = ctxt;
596 Gssctxt *gssctxt;
597 gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
598 gss_buffer_desc recv_tok;
599 OM_uint32 status, ms;
600 u_int slen;
601
602 if (authctxt == NULL)
603 fatal("input_gssapi_response: no authentication context");
604 gssctxt = authctxt->methoddata;
605
606 recv_tok.value = packet_get_string(&slen);
607 recv_tok.length = slen; /* safe typecast */
608
609 packet_check_eom();
610
611 status=ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
612 &recv_tok, &send_tok, NULL);
613
614 xfree(recv_tok.value);
615
616 if (GSS_ERROR(status)) {
617 if (send_tok.length > 0) {
618 packet_start(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK);
619 packet_put_string(send_tok.value, send_tok.length);
620 packet_send();
621 gss_release_buffer(&ms, &send_tok);
622 }
623 /* Start again with the next method in the list */
624 userauth(authctxt, NULL);
625 return;
626 }
627
628 if (send_tok.length > 0) {
629 packet_start(SSH2_MSG_USERAUTH_GSSAPI_TOKEN);
630 packet_put_string(send_tok.value, send_tok.length);
631 packet_send();
632 gss_release_buffer(&ms, &send_tok);
633 }
634
635 if (status == GSS_S_COMPLETE) {
636 /* If that succeeded, send a exchange complete message */
637 packet_start(SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE);
638 packet_send();
639 }
640}
641
642void
643input_gssapi_errtok(int type, u_int32_t plen, void *ctxt)
644{
645 Authctxt *authctxt = ctxt;
646 Gssctxt *gssctxt;
647 gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
648 gss_buffer_desc recv_tok;
649 OM_uint32 status, ms;
Darren Tucker600ad8d2003-08-26 12:10:48 +1000650 u_int len;
Darren Tucker0efd1552003-08-26 11:49:55 +1000651
652 if (authctxt == NULL)
653 fatal("input_gssapi_response: no authentication context");
654 gssctxt = authctxt->methoddata;
655
Darren Tucker600ad8d2003-08-26 12:10:48 +1000656 recv_tok.value = packet_get_string(&len);
657 recv_tok.length = len;
Darren Tucker0efd1552003-08-26 11:49:55 +1000658
659 packet_check_eom();
660
661 /* Stick it into GSSAPI and see what it says */
662 status = ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
663 &recv_tok, &send_tok, NULL);
664
665 xfree(recv_tok.value);
666 gss_release_buffer(&ms, &send_tok);
667
668 /* Server will be returning a failed packet after this one */
669}
670
671void
672input_gssapi_error(int type, u_int32_t plen, void *ctxt)
673{
674 OM_uint32 maj, min;
675 char *msg;
676 char *lang;
677
678 maj=packet_get_int();
679 min=packet_get_int();
680 msg=packet_get_string(NULL);
681 lang=packet_get_string(NULL);
682
683 packet_check_eom();
684
685 debug("Server GSSAPI Error:\n%s\n", msg);
686 xfree(msg);
687 xfree(lang);
688}
689#endif /* GSSAPI */
690
Damien Millereba71ba2000-04-29 23:57:08 +1000691int
Damien Miller874d77b2000-10-14 16:23:11 +1100692userauth_none(Authctxt *authctxt)
693{
694 /* initial userauth request */
695 packet_start(SSH2_MSG_USERAUTH_REQUEST);
696 packet_put_cstring(authctxt->server_user);
697 packet_put_cstring(authctxt->service);
698 packet_put_cstring(authctxt->method->name);
699 packet_send();
Damien Miller874d77b2000-10-14 16:23:11 +1100700 return 1;
701}
702
703int
Damien Miller62cee002000-09-23 17:15:56 +1100704userauth_passwd(Authctxt *authctxt)
Damien Millereba71ba2000-04-29 23:57:08 +1000705{
Damien Millere247cc42000-05-07 12:03:14 +1000706 static int attempt = 0;
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000707 char prompt[150];
Damien Millereba71ba2000-04-29 23:57:08 +1000708 char *password;
709
Damien Millerd3a18572000-06-07 19:55:44 +1000710 if (attempt++ >= options.number_of_password_prompts)
Damien Millere247cc42000-05-07 12:03:14 +1000711 return 0;
712
Ben Lindstrom1c37c6a2001-12-06 18:00:18 +0000713 if (attempt != 1)
Damien Millerd3a18572000-06-07 19:55:44 +1000714 error("Permission denied, please try again.");
715
Ben Lindstrom03df5bd2001-02-10 22:16:41 +0000716 snprintf(prompt, sizeof(prompt), "%.30s@%.128s's password: ",
Damien Miller62cee002000-09-23 17:15:56 +1100717 authctxt->server_user, authctxt->host);
Damien Millereba71ba2000-04-29 23:57:08 +1000718 password = read_passphrase(prompt, 0);
719 packet_start(SSH2_MSG_USERAUTH_REQUEST);
Damien Miller62cee002000-09-23 17:15:56 +1100720 packet_put_cstring(authctxt->server_user);
721 packet_put_cstring(authctxt->service);
Damien Miller874d77b2000-10-14 16:23:11 +1100722 packet_put_cstring(authctxt->method->name);
Damien Millereba71ba2000-04-29 23:57:08 +1000723 packet_put_char(0);
Ben Lindstrom5699c5f2001-03-05 06:17:49 +0000724 packet_put_cstring(password);
Damien Millereba71ba2000-04-29 23:57:08 +1000725 memset(password, 0, strlen(password));
726 xfree(password);
Damien Miller9f643902001-11-12 11:02:52 +1100727 packet_add_padding(64);
Damien Millereba71ba2000-04-29 23:57:08 +1000728 packet_send();
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000729
Ben Lindstromcb72e4f2002-06-21 00:41:51 +0000730 dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000731 &input_userauth_passwd_changereq);
732
Damien Millereba71ba2000-04-29 23:57:08 +1000733 return 1;
734}
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000735/*
736 * parse PASSWD_CHANGEREQ, prompt user and send SSH2_MSG_USERAUTH_REQUEST
737 */
738void
Tim Ricec8549622002-03-31 12:49:38 -0800739input_userauth_passwd_changereq(int type, u_int32_t seqnr, void *ctxt)
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000740{
741 Authctxt *authctxt = ctxt;
742 char *info, *lang, *password = NULL, *retype = NULL;
743 char prompt[150];
744
745 debug2("input_userauth_passwd_changereq");
746
747 if (authctxt == NULL)
748 fatal("input_userauth_passwd_changereq: "
749 "no authentication context");
750
751 info = packet_get_string(NULL);
752 lang = packet_get_string(NULL);
753 if (strlen(info) > 0)
Damien Miller996acd22003-04-09 20:59:48 +1000754 logit("%s", info);
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000755 xfree(info);
756 xfree(lang);
757 packet_start(SSH2_MSG_USERAUTH_REQUEST);
758 packet_put_cstring(authctxt->server_user);
759 packet_put_cstring(authctxt->service);
760 packet_put_cstring(authctxt->method->name);
761 packet_put_char(1); /* additional info */
Ben Lindstromcb72e4f2002-06-21 00:41:51 +0000762 snprintf(prompt, sizeof(prompt),
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000763 "Enter %.30s@%.128s's old password: ",
764 authctxt->server_user, authctxt->host);
765 password = read_passphrase(prompt, 0);
766 packet_put_cstring(password);
767 memset(password, 0, strlen(password));
768 xfree(password);
769 password = NULL;
770 while (password == NULL) {
Ben Lindstromcb72e4f2002-06-21 00:41:51 +0000771 snprintf(prompt, sizeof(prompt),
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000772 "Enter %.30s@%.128s's new password: ",
773 authctxt->server_user, authctxt->host);
774 password = read_passphrase(prompt, RP_ALLOW_EOF);
775 if (password == NULL) {
776 /* bail out */
777 return;
778 }
Ben Lindstromcb72e4f2002-06-21 00:41:51 +0000779 snprintf(prompt, sizeof(prompt),
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000780 "Retype %.30s@%.128s's new password: ",
781 authctxt->server_user, authctxt->host);
782 retype = read_passphrase(prompt, 0);
783 if (strcmp(password, retype) != 0) {
784 memset(password, 0, strlen(password));
785 xfree(password);
Damien Miller996acd22003-04-09 20:59:48 +1000786 logit("Mismatch; try again, EOF to quit.");
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000787 password = NULL;
788 }
789 memset(retype, 0, strlen(retype));
790 xfree(retype);
791 }
792 packet_put_cstring(password);
793 memset(password, 0, strlen(password));
794 xfree(password);
795 packet_add_padding(64);
796 packet_send();
Ben Lindstromcb72e4f2002-06-21 00:41:51 +0000797
798 dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000799 &input_userauth_passwd_changereq);
800}
Damien Millereba71ba2000-04-29 23:57:08 +1000801
Ben Lindstrombba81212001-06-25 05:01:22 +0000802static int
Damien Miller280ecfb2003-05-14 13:46:00 +1000803identity_sign(Identity *id, u_char **sigp, u_int *lenp,
804 u_char *data, u_int datalen)
805{
806 Key *prv;
807 int ret;
808
809 /* the agent supports this key */
810 if (id->ac)
811 return (ssh_agent_sign(id->ac, id->key, sigp, lenp,
812 data, datalen));
813 /*
814 * we have already loaded the private key or
815 * the private key is stored in external hardware
816 */
817 if (id->isprivate || (id->key->flags & KEY_FLAG_EXT))
818 return (key_sign(id->key, sigp, lenp, data, datalen));
819 /* load the private key from the file */
820 if ((prv = load_identity_file(id->filename)) == NULL)
821 return (-1);
822 ret = key_sign(prv, sigp, lenp, data, datalen);
823 key_free(prv);
824 return (ret);
825}
826
827static int
828sign_and_send_pubkey(Authctxt *authctxt, Identity *id)
Damien Millereba71ba2000-04-29 23:57:08 +1000829{
830 Buffer b;
Ben Lindstrom46c16222000-12-22 01:43:59 +0000831 u_char *blob, *signature;
Ben Lindstrom90fd8142002-02-26 18:09:42 +0000832 u_int bloblen, slen;
Darren Tucker502d3842003-06-28 12:38:01 +1000833 u_int skip = 0;
Damien Millerad833b32000-08-23 10:46:23 +1000834 int ret = -1;
Damien Miller874d77b2000-10-14 16:23:11 +1100835 int have_sig = 1;
Damien Millereba71ba2000-04-29 23:57:08 +1000836
Ben Lindstromd121f612000-12-03 17:00:47 +0000837 debug3("sign_and_send_pubkey");
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000838
Damien Miller280ecfb2003-05-14 13:46:00 +1000839 if (key_to_blob(id->key, &blob, &bloblen) == 0) {
Damien Miller0bc1bd82000-11-13 22:57:25 +1100840 /* we cannot handle this key */
Ben Lindstromd121f612000-12-03 17:00:47 +0000841 debug3("sign_and_send_pubkey: cannot handle key");
Damien Miller0bc1bd82000-11-13 22:57:25 +1100842 return 0;
843 }
Damien Millereba71ba2000-04-29 23:57:08 +1000844 /* data to be signed */
845 buffer_init(&b);
Damien Miller50a41ed2000-10-16 12:14:42 +1100846 if (datafellows & SSH_OLD_SESSIONID) {
Damien Miller6536c7d2000-06-22 21:32:31 +1000847 buffer_append(&b, session_id2, session_id2_len);
Kevin Stevesef4eea92001-02-05 12:42:17 +0000848 skip = session_id2_len;
Damien Miller50a41ed2000-10-16 12:14:42 +1100849 } else {
850 buffer_put_string(&b, session_id2, session_id2_len);
851 skip = buffer_len(&b);
Damien Miller6536c7d2000-06-22 21:32:31 +1000852 }
Damien Millereba71ba2000-04-29 23:57:08 +1000853 buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
Damien Miller62cee002000-09-23 17:15:56 +1100854 buffer_put_cstring(&b, authctxt->server_user);
Damien Miller30c3d422000-05-09 11:02:59 +1000855 buffer_put_cstring(&b,
Ben Lindstromd121f612000-12-03 17:00:47 +0000856 datafellows & SSH_BUG_PKSERVICE ?
Damien Miller30c3d422000-05-09 11:02:59 +1000857 "ssh-userauth" :
Damien Miller62cee002000-09-23 17:15:56 +1100858 authctxt->service);
Ben Lindstromd121f612000-12-03 17:00:47 +0000859 if (datafellows & SSH_BUG_PKAUTH) {
860 buffer_put_char(&b, have_sig);
861 } else {
862 buffer_put_cstring(&b, authctxt->method->name);
863 buffer_put_char(&b, have_sig);
Damien Miller280ecfb2003-05-14 13:46:00 +1000864 buffer_put_cstring(&b, key_ssh_name(id->key));
Ben Lindstromd121f612000-12-03 17:00:47 +0000865 }
Damien Millereba71ba2000-04-29 23:57:08 +1000866 buffer_put_string(&b, blob, bloblen);
Damien Millereba71ba2000-04-29 23:57:08 +1000867
868 /* generate signature */
Damien Miller280ecfb2003-05-14 13:46:00 +1000869 ret = identity_sign(id, &signature, &slen,
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000870 buffer_ptr(&b), buffer_len(&b));
Damien Millerad833b32000-08-23 10:46:23 +1000871 if (ret == -1) {
872 xfree(blob);
873 buffer_free(&b);
874 return 0;
875 }
Damien Miller0bc1bd82000-11-13 22:57:25 +1100876#ifdef DEBUG_PK
Damien Millereba71ba2000-04-29 23:57:08 +1000877 buffer_dump(&b);
878#endif
Ben Lindstromd121f612000-12-03 17:00:47 +0000879 if (datafellows & SSH_BUG_PKSERVICE) {
Damien Miller30c3d422000-05-09 11:02:59 +1000880 buffer_clear(&b);
881 buffer_append(&b, session_id2, session_id2_len);
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000882 skip = session_id2_len;
Damien Miller30c3d422000-05-09 11:02:59 +1000883 buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
Damien Miller62cee002000-09-23 17:15:56 +1100884 buffer_put_cstring(&b, authctxt->server_user);
885 buffer_put_cstring(&b, authctxt->service);
Damien Miller874d77b2000-10-14 16:23:11 +1100886 buffer_put_cstring(&b, authctxt->method->name);
887 buffer_put_char(&b, have_sig);
Ben Lindstromd121f612000-12-03 17:00:47 +0000888 if (!(datafellows & SSH_BUG_PKAUTH))
Damien Miller280ecfb2003-05-14 13:46:00 +1000889 buffer_put_cstring(&b, key_ssh_name(id->key));
Damien Miller30c3d422000-05-09 11:02:59 +1000890 buffer_put_string(&b, blob, bloblen);
891 }
892 xfree(blob);
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000893
Damien Millereba71ba2000-04-29 23:57:08 +1000894 /* append signature */
895 buffer_put_string(&b, signature, slen);
896 xfree(signature);
897
898 /* skip session id and packet type */
Damien Miller6536c7d2000-06-22 21:32:31 +1000899 if (buffer_len(&b) < skip + 1)
Damien Miller62cee002000-09-23 17:15:56 +1100900 fatal("userauth_pubkey: internal error");
Damien Miller6536c7d2000-06-22 21:32:31 +1000901 buffer_consume(&b, skip + 1);
Damien Millereba71ba2000-04-29 23:57:08 +1000902
903 /* put remaining data from buffer into packet */
904 packet_start(SSH2_MSG_USERAUTH_REQUEST);
905 packet_put_raw(buffer_ptr(&b), buffer_len(&b));
906 buffer_free(&b);
Damien Millereba71ba2000-04-29 23:57:08 +1000907 packet_send();
Damien Millerad833b32000-08-23 10:46:23 +1000908
909 return 1;
Damien Miller994cf142000-07-21 10:19:44 +1000910}
911
Ben Lindstrombba81212001-06-25 05:01:22 +0000912static int
Damien Miller280ecfb2003-05-14 13:46:00 +1000913send_pubkey_test(Authctxt *authctxt, Identity *id)
Damien Miller994cf142000-07-21 10:19:44 +1000914{
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000915 u_char *blob;
Ben Lindstromc58ab022002-02-26 18:15:09 +0000916 u_int bloblen, have_sig = 0;
Damien Miller994cf142000-07-21 10:19:44 +1000917
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000918 debug3("send_pubkey_test");
919
Damien Miller280ecfb2003-05-14 13:46:00 +1000920 if (key_to_blob(id->key, &blob, &bloblen) == 0) {
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000921 /* we cannot handle this key */
922 debug3("send_pubkey_test: cannot handle key");
Damien Miller994cf142000-07-21 10:19:44 +1000923 return 0;
924 }
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000925 /* register callback for USERAUTH_PK_OK message */
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000926 dispatch_set(SSH2_MSG_USERAUTH_PK_OK, &input_userauth_pk_ok);
Damien Miller994cf142000-07-21 10:19:44 +1000927
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000928 packet_start(SSH2_MSG_USERAUTH_REQUEST);
929 packet_put_cstring(authctxt->server_user);
930 packet_put_cstring(authctxt->service);
931 packet_put_cstring(authctxt->method->name);
932 packet_put_char(have_sig);
933 if (!(datafellows & SSH_BUG_PKAUTH))
Damien Miller280ecfb2003-05-14 13:46:00 +1000934 packet_put_cstring(key_ssh_name(id->key));
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000935 packet_put_string(blob, bloblen);
936 xfree(blob);
937 packet_send();
938 return 1;
939}
940
Ben Lindstrombba81212001-06-25 05:01:22 +0000941static Key *
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000942load_identity_file(char *filename)
943{
944 Key *private;
945 char prompt[300], *passphrase;
Ben Lindstromd0fca422001-03-26 13:44:06 +0000946 int quit, i;
Ben Lindstrom329782e2001-03-10 17:08:59 +0000947 struct stat st;
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000948
Ben Lindstrom329782e2001-03-10 17:08:59 +0000949 if (stat(filename, &st) < 0) {
950 debug3("no such identity: %s", filename);
951 return NULL;
952 }
Ben Lindstromd0fca422001-03-26 13:44:06 +0000953 private = key_load_private_type(KEY_UNSPEC, filename, "", NULL);
954 if (private == NULL) {
955 if (options.batch_mode)
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000956 return NULL;
Damien Miller994cf142000-07-21 10:19:44 +1000957 snprintf(prompt, sizeof prompt,
Damien Miller9f0f5c62001-12-21 14:45:46 +1100958 "Enter passphrase for key '%.100s': ", filename);
Damien Miller62cee002000-09-23 17:15:56 +1100959 for (i = 0; i < options.number_of_password_prompts; i++) {
960 passphrase = read_passphrase(prompt, 0);
961 if (strcmp(passphrase, "") != 0) {
Ben Lindstromd0fca422001-03-26 13:44:06 +0000962 private = key_load_private_type(KEY_UNSPEC, filename,
963 passphrase, NULL);
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000964 quit = 0;
Damien Miller62cee002000-09-23 17:15:56 +1100965 } else {
966 debug2("no passphrase given, try next key");
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000967 quit = 1;
Damien Miller62cee002000-09-23 17:15:56 +1100968 }
969 memset(passphrase, 0, strlen(passphrase));
970 xfree(passphrase);
Ben Lindstromd0fca422001-03-26 13:44:06 +0000971 if (private != NULL || quit)
Damien Miller62cee002000-09-23 17:15:56 +1100972 break;
973 debug2("bad passphrase given, try again...");
974 }
Damien Miller994cf142000-07-21 10:19:44 +1000975 }
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000976 return private;
977}
978
Damien Miller280ecfb2003-05-14 13:46:00 +1000979/*
980 * try keys in the following order:
981 * 1. agent keys that are found in the config file
982 * 2. other agent keys
983 * 3. keys that are only listed in the config file
984 */
985static void
986pubkey_prepare(Authctxt *authctxt)
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000987{
Damien Miller280ecfb2003-05-14 13:46:00 +1000988 Identity *id;
989 Idlist agent, files, *preferred;
990 Key *key;
991 AuthenticationConnection *ac;
Damien Millerad833b32000-08-23 10:46:23 +1000992 char *comment;
Damien Miller280ecfb2003-05-14 13:46:00 +1000993 int i, found;
Damien Millerad833b32000-08-23 10:46:23 +1000994
Damien Miller280ecfb2003-05-14 13:46:00 +1000995 TAILQ_INIT(&agent); /* keys from the agent */
996 TAILQ_INIT(&files); /* keys from the config file */
997 preferred = &authctxt->keys;
998 TAILQ_INIT(preferred); /* preferred order of keys */
999
1000 /* list of keys stored in the filesystem */
1001 for (i = 0; i < options.num_identity_files; i++) {
1002 key = options.identity_keys[i];
1003 if (key && key->type == KEY_RSA1)
1004 continue;
1005 options.identity_keys[i] = NULL;
1006 id = xmalloc(sizeof(*id));
1007 memset(id, 0, sizeof(*id));
1008 id->key = key;
1009 id->filename = xstrdup(options.identity_files[i]);
1010 TAILQ_INSERT_TAIL(&files, id, next);
Damien Millerad833b32000-08-23 10:46:23 +10001011 }
Damien Miller280ecfb2003-05-14 13:46:00 +10001012 /* list of keys supported by the agent */
1013 if ((ac = ssh_get_authentication_connection())) {
1014 for (key = ssh_get_first_identity(ac, &comment, 2);
1015 key != NULL;
1016 key = ssh_get_next_identity(ac, &comment, 2)) {
1017 found = 0;
1018 TAILQ_FOREACH(id, &files, next) {
1019 /* agent keys from the config file are preferred */
1020 if (key_equal(key, id->key)) {
1021 key_free(key);
1022 xfree(comment);
1023 TAILQ_REMOVE(&files, id, next);
1024 TAILQ_INSERT_TAIL(preferred, id, next);
1025 id->ac = ac;
1026 found = 1;
1027 break;
1028 }
1029 }
1030 if (!found) {
1031 id = xmalloc(sizeof(*id));
1032 memset(id, 0, sizeof(*id));
1033 id->key = key;
1034 id->filename = comment;
1035 id->ac = ac;
1036 TAILQ_INSERT_TAIL(&agent, id, next);
1037 }
1038 }
1039 /* append remaining agent keys */
1040 for (id = TAILQ_FIRST(&agent); id; id = TAILQ_FIRST(&agent)) {
1041 TAILQ_REMOVE(&agent, id, next);
1042 TAILQ_INSERT_TAIL(preferred, id, next);
1043 }
1044 authctxt->agent = ac;
Damien Miller62cee002000-09-23 17:15:56 +11001045 }
Damien Miller280ecfb2003-05-14 13:46:00 +10001046 /* append remaining keys from the config file */
1047 for (id = TAILQ_FIRST(&files); id; id = TAILQ_FIRST(&files)) {
1048 TAILQ_REMOVE(&files, id, next);
1049 TAILQ_INSERT_TAIL(preferred, id, next);
1050 }
1051 TAILQ_FOREACH(id, preferred, next) {
1052 debug2("key: %s (%p)", id->filename, id->key);
1053 }
1054}
1055
1056static void
1057pubkey_cleanup(Authctxt *authctxt)
1058{
1059 Identity *id;
1060
1061 if (authctxt->agent != NULL)
1062 ssh_close_authentication_connection(authctxt->agent);
1063 for (id = TAILQ_FIRST(&authctxt->keys); id;
1064 id = TAILQ_FIRST(&authctxt->keys)) {
1065 TAILQ_REMOVE(&authctxt->keys, id, next);
1066 if (id->key)
1067 key_free(id->key);
1068 if (id->filename)
1069 xfree(id->filename);
1070 xfree(id);
1071 }
Damien Millereba71ba2000-04-29 23:57:08 +10001072}
1073
Damien Miller62cee002000-09-23 17:15:56 +11001074int
1075userauth_pubkey(Authctxt *authctxt)
Damien Millereba71ba2000-04-29 23:57:08 +10001076{
Damien Miller280ecfb2003-05-14 13:46:00 +10001077 Identity *id;
Damien Miller62cee002000-09-23 17:15:56 +11001078 int sent = 0;
Damien Millereba71ba2000-04-29 23:57:08 +10001079
Damien Miller280ecfb2003-05-14 13:46:00 +10001080 while ((id = TAILQ_FIRST(&authctxt->keys))) {
1081 if (id->tried++)
1082 return (0);
1083 TAILQ_REMOVE(&authctxt->keys, id, next);
1084 TAILQ_INSERT_TAIL(&authctxt->keys, id, next);
1085 /*
1086 * send a test message if we have the public key. for
1087 * encrypted keys we cannot do this and have to load the
1088 * private key instead
1089 */
1090 if (id->key && id->key->type != KEY_RSA1) {
1091 debug("Offering public key: %s", id->filename);
1092 sent = send_pubkey_test(authctxt, id);
1093 } else if (id->key == NULL) {
1094 debug("Trying private key: %s", id->filename);
1095 id->key = load_identity_file(id->filename);
1096 if (id->key != NULL) {
1097 id->isprivate = 1;
1098 sent = sign_and_send_pubkey(authctxt, id);
1099 key_free(id->key);
1100 id->key = NULL;
Ben Lindstrom266dfdf2001-03-09 00:12:22 +00001101 }
Ben Lindstrom266dfdf2001-03-09 00:12:22 +00001102 }
Damien Miller280ecfb2003-05-14 13:46:00 +10001103 if (sent)
1104 return (sent);
Damien Miller0bc1bd82000-11-13 22:57:25 +11001105 }
Damien Miller280ecfb2003-05-14 13:46:00 +10001106 return (0);
Damien Miller62cee002000-09-23 17:15:56 +11001107}
Damien Millereba71ba2000-04-29 23:57:08 +10001108
Damien Miller874d77b2000-10-14 16:23:11 +11001109/*
1110 * Send userauth request message specifying keyboard-interactive method.
1111 */
1112int
1113userauth_kbdint(Authctxt *authctxt)
1114{
1115 static int attempt = 0;
1116
1117 if (attempt++ >= options.number_of_password_prompts)
1118 return 0;
Ben Lindstrom7d199962001-09-12 18:29:00 +00001119 /* disable if no SSH2_MSG_USERAUTH_INFO_REQUEST has been seen */
1120 if (attempt > 1 && !authctxt->info_req_seen) {
1121 debug3("userauth_kbdint: disable: no info_req_seen");
1122 dispatch_set(SSH2_MSG_USERAUTH_INFO_REQUEST, NULL);
1123 return 0;
1124 }
Damien Miller874d77b2000-10-14 16:23:11 +11001125
1126 debug2("userauth_kbdint");
1127 packet_start(SSH2_MSG_USERAUTH_REQUEST);
1128 packet_put_cstring(authctxt->server_user);
1129 packet_put_cstring(authctxt->service);
1130 packet_put_cstring(authctxt->method->name);
1131 packet_put_cstring(""); /* lang */
1132 packet_put_cstring(options.kbd_interactive_devices ?
1133 options.kbd_interactive_devices : "");
1134 packet_send();
Damien Miller874d77b2000-10-14 16:23:11 +11001135
1136 dispatch_set(SSH2_MSG_USERAUTH_INFO_REQUEST, &input_userauth_info_req);
1137 return 1;
1138}
1139
1140/*
Ben Lindstrom03df5bd2001-02-10 22:16:41 +00001141 * parse INFO_REQUEST, prompt user and send INFO_RESPONSE
Damien Miller874d77b2000-10-14 16:23:11 +11001142 */
1143void
Damien Miller630d6f42002-01-22 23:17:30 +11001144input_userauth_info_req(int type, u_int32_t seq, void *ctxt)
Damien Miller874d77b2000-10-14 16:23:11 +11001145{
1146 Authctxt *authctxt = ctxt;
Ben Lindstrom03df5bd2001-02-10 22:16:41 +00001147 char *name, *inst, *lang, *prompt, *response;
Ben Lindstrom46c16222000-12-22 01:43:59 +00001148 u_int num_prompts, i;
Damien Miller874d77b2000-10-14 16:23:11 +11001149 int echo = 0;
1150
1151 debug2("input_userauth_info_req");
1152
1153 if (authctxt == NULL)
1154 fatal("input_userauth_info_req: no authentication context");
1155
Ben Lindstrom7d199962001-09-12 18:29:00 +00001156 authctxt->info_req_seen = 1;
1157
Damien Miller874d77b2000-10-14 16:23:11 +11001158 name = packet_get_string(NULL);
1159 inst = packet_get_string(NULL);
1160 lang = packet_get_string(NULL);
Damien Miller874d77b2000-10-14 16:23:11 +11001161 if (strlen(name) > 0)
Damien Miller996acd22003-04-09 20:59:48 +10001162 logit("%s", name);
Damien Miller874d77b2000-10-14 16:23:11 +11001163 if (strlen(inst) > 0)
Damien Miller996acd22003-04-09 20:59:48 +10001164 logit("%s", inst);
Ben Lindstrom03df5bd2001-02-10 22:16:41 +00001165 xfree(name);
Damien Miller874d77b2000-10-14 16:23:11 +11001166 xfree(inst);
Ben Lindstrom03df5bd2001-02-10 22:16:41 +00001167 xfree(lang);
Damien Miller874d77b2000-10-14 16:23:11 +11001168
1169 num_prompts = packet_get_int();
1170 /*
1171 * Begin to build info response packet based on prompts requested.
1172 * We commit to providing the correct number of responses, so if
1173 * further on we run into a problem that prevents this, we have to
1174 * be sure and clean this up and send a correct error response.
1175 */
1176 packet_start(SSH2_MSG_USERAUTH_INFO_RESPONSE);
1177 packet_put_int(num_prompts);
1178
Ben Lindstrom551ea372001-06-05 18:56:16 +00001179 debug2("input_userauth_info_req: num_prompts %d", num_prompts);
Damien Miller874d77b2000-10-14 16:23:11 +11001180 for (i = 0; i < num_prompts; i++) {
1181 prompt = packet_get_string(NULL);
1182 echo = packet_get_char();
1183
Ben Lindstrom949974b2001-06-25 05:20:31 +00001184 response = read_passphrase(prompt, echo ? RP_ECHO : 0);
Damien Miller874d77b2000-10-14 16:23:11 +11001185
Ben Lindstrom5699c5f2001-03-05 06:17:49 +00001186 packet_put_cstring(response);
Damien Miller874d77b2000-10-14 16:23:11 +11001187 memset(response, 0, strlen(response));
1188 xfree(response);
1189 xfree(prompt);
1190 }
Damien Miller48b03fc2002-01-22 23:11:40 +11001191 packet_check_eom(); /* done with parsing incoming message. */
Damien Miller874d77b2000-10-14 16:23:11 +11001192
Damien Miller9f643902001-11-12 11:02:52 +11001193 packet_add_padding(64);
Damien Miller874d77b2000-10-14 16:23:11 +11001194 packet_send();
Damien Miller874d77b2000-10-14 16:23:11 +11001195}
Damien Miller62cee002000-09-23 17:15:56 +11001196
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001197static int
Ben Lindstrom5c385522002-06-23 21:23:20 +00001198ssh_keysign(Key *key, u_char **sigp, u_int *lenp,
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001199 u_char *data, u_int datalen)
1200{
1201 Buffer b;
Ben Lindstrom5206b952002-06-06 19:59:29 +00001202 struct stat st;
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001203 pid_t pid;
Ben Lindstromcec2ea82002-06-06 20:51:04 +00001204 int to[2], from[2], status, version = 2;
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001205
Ben Lindstrom1d568f92002-12-23 02:44:36 +00001206 debug2("ssh_keysign called");
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001207
Ben Lindstrom5206b952002-06-06 19:59:29 +00001208 if (stat(_PATH_SSH_KEY_SIGN, &st) < 0) {
1209 error("ssh_keysign: no installed: %s", strerror(errno));
1210 return -1;
1211 }
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001212 if (fflush(stdout) != 0)
1213 error("ssh_keysign: fflush: %s", strerror(errno));
1214 if (pipe(to) < 0) {
1215 error("ssh_keysign: pipe: %s", strerror(errno));
1216 return -1;
1217 }
1218 if (pipe(from) < 0) {
1219 error("ssh_keysign: pipe: %s", strerror(errno));
1220 return -1;
1221 }
1222 if ((pid = fork()) < 0) {
1223 error("ssh_keysign: fork: %s", strerror(errno));
1224 return -1;
1225 }
1226 if (pid == 0) {
1227 seteuid(getuid());
1228 setuid(getuid());
1229 close(from[0]);
1230 if (dup2(from[1], STDOUT_FILENO) < 0)
1231 fatal("ssh_keysign: dup2: %s", strerror(errno));
1232 close(to[1]);
1233 if (dup2(to[0], STDIN_FILENO) < 0)
1234 fatal("ssh_keysign: dup2: %s", strerror(errno));
Ben Lindstromcec2ea82002-06-06 20:51:04 +00001235 close(from[1]);
1236 close(to[0]);
Ben Lindstrom4887da22002-06-06 20:05:57 +00001237 execl(_PATH_SSH_KEY_SIGN, _PATH_SSH_KEY_SIGN, (char *) 0);
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001238 fatal("ssh_keysign: exec(%s): %s", _PATH_SSH_KEY_SIGN,
1239 strerror(errno));
1240 }
1241 close(from[1]);
1242 close(to[0]);
1243
1244 buffer_init(&b);
Ben Lindstromcec2ea82002-06-06 20:51:04 +00001245 buffer_put_int(&b, packet_get_connection_in()); /* send # of socket */
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001246 buffer_put_string(&b, data, datalen);
Damien Miller901119b2002-10-04 11:10:04 +10001247 ssh_msg_send(to[1], version, &b);
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001248
Damien Miller901119b2002-10-04 11:10:04 +10001249 if (ssh_msg_recv(from[0], &b) < 0) {
Ben Lindstrom5206b952002-06-06 19:59:29 +00001250 error("ssh_keysign: no reply");
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001251 buffer_clear(&b);
1252 return -1;
1253 }
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001254 close(from[0]);
1255 close(to[1]);
1256
Ben Lindstromcec2ea82002-06-06 20:51:04 +00001257 while (waitpid(pid, &status, 0) < 0)
1258 if (errno != EINTR)
1259 break;
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001260
Ben Lindstrom5206b952002-06-06 19:59:29 +00001261 if (buffer_get_char(&b) != version) {
1262 error("ssh_keysign: bad version");
1263 buffer_clear(&b);
1264 return -1;
1265 }
1266 *sigp = buffer_get_string(&b, lenp);
1267 buffer_clear(&b);
1268
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001269 return 0;
1270}
1271
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001272int
1273userauth_hostbased(Authctxt *authctxt)
1274{
1275 Key *private = NULL;
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001276 Sensitive *sensitive = authctxt->sensitive;
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001277 Buffer b;
1278 u_char *signature, *blob;
1279 char *chost, *pkalg, *p;
Ben Lindstrom671388f2001-04-19 20:40:45 +00001280 const char *service;
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001281 u_int blen, slen;
Ben Lindstrom2bffd6f2001-04-19 20:35:40 +00001282 int ok, i, len, found = 0;
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001283
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001284 /* check for a useful key */
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001285 for (i = 0; i < sensitive->nkeys; i++) {
1286 private = sensitive->keys[i];
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001287 if (private && private->type != KEY_RSA1) {
1288 found = 1;
1289 /* we take and free the key */
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001290 sensitive->keys[i] = NULL;
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001291 break;
1292 }
1293 }
1294 if (!found) {
Ben Lindstrom1d568f92002-12-23 02:44:36 +00001295 debug("No more client hostkeys for hostbased authentication.");
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001296 return 0;
1297 }
1298 if (key_to_blob(private, &blob, &blen) == 0) {
1299 key_free(private);
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001300 return 0;
1301 }
Damien Miller91c18472001-11-12 11:02:03 +11001302 /* figure out a name for the client host */
1303 p = get_local_name(packet_get_connection_in());
1304 if (p == NULL) {
1305 error("userauth_hostbased: cannot get local ipaddr/name");
1306 key_free(private);
1307 return 0;
1308 }
1309 len = strlen(p) + 2;
1310 chost = xmalloc(len);
1311 strlcpy(chost, p, len);
1312 strlcat(chost, ".", len);
1313 debug2("userauth_hostbased: chost %s", chost);
Damien Miller00111382003-03-10 11:21:17 +11001314 xfree(p);
Damien Miller91c18472001-11-12 11:02:03 +11001315
Ben Lindstrom671388f2001-04-19 20:40:45 +00001316 service = datafellows & SSH_BUG_HBSERVICE ? "ssh-userauth" :
1317 authctxt->service;
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001318 pkalg = xstrdup(key_ssh_name(private));
1319 buffer_init(&b);
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001320 /* construct data */
Ben Lindstrom671388f2001-04-19 20:40:45 +00001321 buffer_put_string(&b, session_id2, session_id2_len);
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001322 buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
1323 buffer_put_cstring(&b, authctxt->server_user);
Ben Lindstrom671388f2001-04-19 20:40:45 +00001324 buffer_put_cstring(&b, service);
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001325 buffer_put_cstring(&b, authctxt->method->name);
1326 buffer_put_cstring(&b, pkalg);
1327 buffer_put_string(&b, blob, blen);
1328 buffer_put_cstring(&b, chost);
1329 buffer_put_cstring(&b, authctxt->local_user);
1330#ifdef DEBUG_PK
1331 buffer_dump(&b);
1332#endif
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001333 if (sensitive->external_keysign)
1334 ok = ssh_keysign(private, &signature, &slen,
1335 buffer_ptr(&b), buffer_len(&b));
1336 else
1337 ok = key_sign(private, &signature, &slen,
1338 buffer_ptr(&b), buffer_len(&b));
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001339 key_free(private);
1340 buffer_free(&b);
1341 if (ok != 0) {
1342 error("key_sign failed");
1343 xfree(chost);
1344 xfree(pkalg);
1345 return 0;
1346 }
1347 packet_start(SSH2_MSG_USERAUTH_REQUEST);
1348 packet_put_cstring(authctxt->server_user);
1349 packet_put_cstring(authctxt->service);
1350 packet_put_cstring(authctxt->method->name);
1351 packet_put_cstring(pkalg);
1352 packet_put_string(blob, blen);
1353 packet_put_cstring(chost);
1354 packet_put_cstring(authctxt->local_user);
1355 packet_put_string(signature, slen);
1356 memset(signature, 's', slen);
1357 xfree(signature);
1358 xfree(chost);
1359 xfree(pkalg);
1360
1361 packet_send();
1362 return 1;
1363}
1364
Damien Miller62cee002000-09-23 17:15:56 +11001365/* find auth method */
1366
Damien Miller62cee002000-09-23 17:15:56 +11001367/*
1368 * given auth method name, if configurable options permit this method fill
1369 * in auth_ident field and return true, otherwise return false.
1370 */
Ben Lindstrombba81212001-06-25 05:01:22 +00001371static int
Damien Miller62cee002000-09-23 17:15:56 +11001372authmethod_is_enabled(Authmethod *method)
1373{
1374 if (method == NULL)
1375 return 0;
1376 /* return false if options indicate this method is disabled */
1377 if (method->enabled == NULL || *method->enabled == 0)
1378 return 0;
1379 /* return false if batch mode is enabled but method needs interactive mode */
1380 if (method->batch_flag != NULL && *method->batch_flag != 0)
1381 return 0;
1382 return 1;
1383}
1384
Ben Lindstrombba81212001-06-25 05:01:22 +00001385static Authmethod *
Damien Miller62cee002000-09-23 17:15:56 +11001386authmethod_lookup(const char *name)
1387{
1388 Authmethod *method = NULL;
1389 if (name != NULL)
1390 for (method = authmethods; method->name != NULL; method++)
1391 if (strcmp(name, method->name) == 0)
1392 return method;
1393 debug2("Unrecognized authentication method name: %s", name ? name : "NULL");
1394 return NULL;
1395}
1396
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001397/* XXX internal state */
1398static Authmethod *current = NULL;
1399static char *supported = NULL;
1400static char *preferred = NULL;
Ben Lindstrom5c385522002-06-23 21:23:20 +00001401
Damien Miller62cee002000-09-23 17:15:56 +11001402/*
1403 * Given the authentication method list sent by the server, return the
1404 * next method we should try. If the server initially sends a nil list,
Ben Lindstroma3700052001-04-05 23:26:32 +00001405 * use a built-in default list.
Kevin Stevesef4eea92001-02-05 12:42:17 +00001406 */
Ben Lindstrombba81212001-06-25 05:01:22 +00001407static Authmethod *
Damien Miller62cee002000-09-23 17:15:56 +11001408authmethod_get(char *authlist)
1409{
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001410 char *name = NULL;
Ben Lindstromc58ab022002-02-26 18:15:09 +00001411 u_int next;
Kevin Stevesef4eea92001-02-05 12:42:17 +00001412
Damien Miller62cee002000-09-23 17:15:56 +11001413 /* Use a suitable default if we're passed a nil list. */
1414 if (authlist == NULL || strlen(authlist) == 0)
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001415 authlist = options.preferred_authentications;
Damien Miller62cee002000-09-23 17:15:56 +11001416
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001417 if (supported == NULL || strcmp(authlist, supported) != 0) {
1418 debug3("start over, passed a different list %s", authlist);
1419 if (supported != NULL)
1420 xfree(supported);
1421 supported = xstrdup(authlist);
1422 preferred = options.preferred_authentications;
1423 debug3("preferred %s", preferred);
1424 current = NULL;
1425 } else if (current != NULL && authmethod_is_enabled(current))
1426 return current;
Damien Millereba71ba2000-04-29 23:57:08 +10001427
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001428 for (;;) {
1429 if ((name = match_list(preferred, supported, &next)) == NULL) {
Ben Lindstrom1d568f92002-12-23 02:44:36 +00001430 debug("No more authentication methods to try.");
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001431 current = NULL;
1432 return NULL;
Damien Miller874d77b2000-10-14 16:23:11 +11001433 }
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001434 preferred += next;
1435 debug3("authmethod_lookup %s", name);
1436 debug3("remaining preferred: %s", preferred);
1437 if ((current = authmethod_lookup(name)) != NULL &&
1438 authmethod_is_enabled(current)) {
1439 debug3("authmethod_is_enabled %s", name);
Ben Lindstrom1d568f92002-12-23 02:44:36 +00001440 debug("Next authentication method: %s", name);
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001441 return current;
1442 }
Damien Millereba71ba2000-04-29 23:57:08 +10001443 }
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001444}
Damien Miller62cee002000-09-23 17:15:56 +11001445
Ben Lindstrom79073822001-07-04 03:42:30 +00001446static char *
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001447authmethods_get(void)
1448{
1449 Authmethod *method = NULL;
Damien Miller0e3b8722002-01-22 23:26:38 +11001450 Buffer b;
1451 char *list;
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001452
Damien Miller0e3b8722002-01-22 23:26:38 +11001453 buffer_init(&b);
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001454 for (method = authmethods; method->name != NULL; method++) {
1455 if (authmethod_is_enabled(method)) {
Damien Miller0e3b8722002-01-22 23:26:38 +11001456 if (buffer_len(&b) > 0)
1457 buffer_append(&b, ",", 1);
1458 buffer_append(&b, method->name, strlen(method->name));
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001459 }
Damien Miller62cee002000-09-23 17:15:56 +11001460 }
Damien Miller0e3b8722002-01-22 23:26:38 +11001461 buffer_append(&b, "\0", 1);
1462 list = xstrdup(buffer_ptr(&b));
1463 buffer_free(&b);
1464 return list;
Damien Millereba71ba2000-04-29 23:57:08 +10001465}