blob: 68d56d02075f6a61af66748f367078425a03ca96 [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"
Damien Millerf675fc42004-06-15 10:30:09 +100026RCSID("$OpenBSD: sshconnect2.c,v 1.138 2004/06/13 12:53:24 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"
Darren Tuckere608ca22004-05-13 16:15:47 +100046#include "misc.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;
Damien Millerf675fc42004-06-15 10:30:09 +1000123 kex->kex[KEX_DH_GRP14_SHA1] = kexdh_client;
Damien Miller8e7fb332003-02-24 12:03:03 +1100124 kex->kex[KEX_DH_GEX_SHA1] = kexgex_client;
Ben Lindstrom20d7c7b2001-04-04 01:56:17 +0000125 kex->client_version_string=client_version_string;
126 kex->server_version_string=server_version_string;
Ben Lindstromd6481ea2001-06-25 04:37:41 +0000127 kex->verify_host_key=&verify_host_key_callback;
Damien Miller874d77b2000-10-14 16:23:11 +1100128
Ben Lindstromf28f6342001-04-04 02:03:04 +0000129 xxx_kex = kex;
130
Ben Lindstrombe2cc432001-04-04 23:46:07 +0000131 dispatch_run(DISPATCH_BLOCK, &kex->done, kex);
Damien Miller874d77b2000-10-14 16:23:11 +1100132
Ben Lindstrom2d90e002001-04-04 02:00:54 +0000133 session_id2 = kex->session_id;
134 session_id2_len = kex->session_id_len;
135
Damien Miller874d77b2000-10-14 16:23:11 +1100136#ifdef DEBUG_KEXDH
137 /* send 1st encrypted/maced/compressed message */
138 packet_start(SSH2_MSG_IGNORE);
139 packet_put_cstring("markus");
140 packet_send();
141 packet_write_wait();
142#endif
Damien Millereba71ba2000-04-29 23:57:08 +1000143}
Damien Millerb1715dc2000-05-30 13:44:51 +1000144
Damien Millereba71ba2000-04-29 23:57:08 +1000145/*
146 * Authenticate user
147 */
Damien Miller62cee002000-09-23 17:15:56 +1100148
149typedef struct Authctxt Authctxt;
150typedef struct Authmethod Authmethod;
Damien Miller280ecfb2003-05-14 13:46:00 +1000151typedef struct identity Identity;
152typedef struct idlist Idlist;
Damien Miller62cee002000-09-23 17:15:56 +1100153
Damien Miller280ecfb2003-05-14 13:46:00 +1000154struct identity {
155 TAILQ_ENTRY(identity) next;
156 AuthenticationConnection *ac; /* set if agent supports key */
157 Key *key; /* public/private key */
158 char *filename; /* comment for agent-only keys */
159 int tried;
160 int isprivate; /* key points to the private key */
161};
162TAILQ_HEAD(idlist, identity);
Damien Miller62cee002000-09-23 17:15:56 +1100163
164struct Authctxt {
165 const char *server_user;
Ben Lindstrom5eabda32001-04-12 23:34:34 +0000166 const char *local_user;
Damien Miller62cee002000-09-23 17:15:56 +1100167 const char *host;
168 const char *service;
Damien Miller62cee002000-09-23 17:15:56 +1100169 Authmethod *method;
Damien Miller874d77b2000-10-14 16:23:11 +1100170 int success;
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000171 char *authlist;
Ben Lindstrom5eabda32001-04-12 23:34:34 +0000172 /* pubkey */
Damien Miller280ecfb2003-05-14 13:46:00 +1000173 Idlist keys;
Ben Lindstrom5eabda32001-04-12 23:34:34 +0000174 AuthenticationConnection *agent;
175 /* hostbased */
Ben Lindstrom1bad2562002-06-06 19:57:33 +0000176 Sensitive *sensitive;
Ben Lindstrom7d199962001-09-12 18:29:00 +0000177 /* kbd-interactive */
178 int info_req_seen;
Darren Tucker0efd1552003-08-26 11:49:55 +1000179 /* generic */
180 void *methoddata;
Damien Miller62cee002000-09-23 17:15:56 +1100181};
182struct Authmethod {
183 char *name; /* string to compare against server's list */
184 int (*userauth)(Authctxt *authctxt);
185 int *enabled; /* flag in option struct that enables method */
186 int *batch_flag; /* flag in option struct that disables method */
187};
188
Damien Miller630d6f42002-01-22 23:17:30 +1100189void input_userauth_success(int, u_int32_t, void *);
190void input_userauth_failure(int, u_int32_t, void *);
191void input_userauth_banner(int, u_int32_t, void *);
192void input_userauth_error(int, u_int32_t, void *);
193void input_userauth_info_req(int, u_int32_t, void *);
194void input_userauth_pk_ok(int, u_int32_t, void *);
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000195void input_userauth_passwd_changereq(int, u_int32_t, void *);
Damien Miller874d77b2000-10-14 16:23:11 +1100196
Ben Lindstrom3c36bb22001-12-06 17:55:26 +0000197int userauth_none(Authctxt *);
198int userauth_pubkey(Authctxt *);
199int userauth_passwd(Authctxt *);
200int userauth_kbdint(Authctxt *);
201int userauth_hostbased(Authctxt *);
Damien Miller3ab496b2003-05-14 13:47:37 +1000202int userauth_kerberos(Authctxt *);
Damien Miller62cee002000-09-23 17:15:56 +1100203
Darren Tucker0efd1552003-08-26 11:49:55 +1000204#ifdef GSSAPI
205int userauth_gssapi(Authctxt *authctxt);
206void input_gssapi_response(int type, u_int32_t, void *);
207void input_gssapi_token(int type, u_int32_t, void *);
208void input_gssapi_hash(int type, u_int32_t, void *);
209void input_gssapi_error(int, u_int32_t, void *);
210void input_gssapi_errtok(int, u_int32_t, void *);
211#endif
212
Ben Lindstrom3c36bb22001-12-06 17:55:26 +0000213void userauth(Authctxt *, char *);
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000214
Damien Miller280ecfb2003-05-14 13:46:00 +1000215static int sign_and_send_pubkey(Authctxt *, Identity *);
Damien Miller280ecfb2003-05-14 13:46:00 +1000216static void pubkey_prepare(Authctxt *);
217static void pubkey_cleanup(Authctxt *);
218static Key *load_identity_file(char *);
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000219
Ben Lindstrombba81212001-06-25 05:01:22 +0000220static Authmethod *authmethod_get(char *authlist);
221static Authmethod *authmethod_lookup(const char *name);
222static char *authmethods_get(void);
Damien Miller62cee002000-09-23 17:15:56 +1100223
224Authmethod authmethods[] = {
Darren Tucker0efd1552003-08-26 11:49:55 +1000225#ifdef GSSAPI
Damien Miller0425d402003-11-17 22:18:21 +1100226 {"gssapi-with-mic",
Darren Tucker0efd1552003-08-26 11:49:55 +1000227 userauth_gssapi,
228 &options.gss_authentication,
229 NULL},
230#endif
Ben Lindstrom1bfe2912001-06-05 19:37:25 +0000231 {"hostbased",
232 userauth_hostbased,
233 &options.hostbased_authentication,
234 NULL},
Ben Lindstrom45350e82001-08-06 20:57:11 +0000235 {"publickey",
236 userauth_pubkey,
237 &options.pubkey_authentication,
238 NULL},
Damien Miller874d77b2000-10-14 16:23:11 +1100239 {"keyboard-interactive",
240 userauth_kbdint,
241 &options.kbd_interactive_authentication,
242 &options.batch_mode},
Ben Lindstrom45350e82001-08-06 20:57:11 +0000243 {"password",
244 userauth_passwd,
245 &options.password_authentication,
246 &options.batch_mode},
Damien Miller874d77b2000-10-14 16:23:11 +1100247 {"none",
248 userauth_none,
249 NULL,
250 NULL},
Damien Miller62cee002000-09-23 17:15:56 +1100251 {NULL, NULL, NULL, NULL}
252};
253
254void
Ben Lindstrom5eabda32001-04-12 23:34:34 +0000255ssh_userauth2(const char *local_user, const char *server_user, char *host,
Ben Lindstrom1bad2562002-06-06 19:57:33 +0000256 Sensitive *sensitive)
Damien Miller62cee002000-09-23 17:15:56 +1100257{
258 Authctxt authctxt;
259 int type;
Damien Miller62cee002000-09-23 17:15:56 +1100260
Ben Lindstrom551ea372001-06-05 18:56:16 +0000261 if (options.challenge_response_authentication)
Ben Lindstrom95fb2dd2001-01-23 03:12:10 +0000262 options.kbd_interactive_authentication = 1;
263
Damien Miller62cee002000-09-23 17:15:56 +1100264 packet_start(SSH2_MSG_SERVICE_REQUEST);
265 packet_put_cstring("ssh-userauth");
266 packet_send();
Ben Lindstrom064496f2002-12-23 02:04:22 +0000267 debug("SSH2_MSG_SERVICE_REQUEST sent");
Damien Miller62cee002000-09-23 17:15:56 +1100268 packet_write_wait();
Damien Millerdff50992002-01-22 23:16:32 +1100269 type = packet_read();
Ben Lindstrom064496f2002-12-23 02:04:22 +0000270 if (type != SSH2_MSG_SERVICE_ACCEPT)
271 fatal("Server denied authentication request: %d", type);
Damien Miller62cee002000-09-23 17:15:56 +1100272 if (packet_remaining() > 0) {
Damien Millerdff50992002-01-22 23:16:32 +1100273 char *reply = packet_get_string(NULL);
Ben Lindstrom064496f2002-12-23 02:04:22 +0000274 debug2("service_accept: %s", reply);
Damien Miller62cee002000-09-23 17:15:56 +1100275 xfree(reply);
Damien Miller62cee002000-09-23 17:15:56 +1100276 } else {
Ben Lindstrom1d568f92002-12-23 02:44:36 +0000277 debug2("buggy server: service_accept w/o service");
Damien Miller62cee002000-09-23 17:15:56 +1100278 }
Damien Miller48b03fc2002-01-22 23:11:40 +1100279 packet_check_eom();
Ben Lindstrom064496f2002-12-23 02:04:22 +0000280 debug("SSH2_MSG_SERVICE_ACCEPT received");
Damien Miller62cee002000-09-23 17:15:56 +1100281
Ben Lindstromb9be60a2001-03-11 01:49:19 +0000282 if (options.preferred_authentications == NULL)
283 options.preferred_authentications = authmethods_get();
284
Damien Miller62cee002000-09-23 17:15:56 +1100285 /* setup authentication context */
Ben Lindstrom7d199962001-09-12 18:29:00 +0000286 memset(&authctxt, 0, sizeof(authctxt));
Damien Miller280ecfb2003-05-14 13:46:00 +1000287 pubkey_prepare(&authctxt);
Damien Miller62cee002000-09-23 17:15:56 +1100288 authctxt.server_user = server_user;
Ben Lindstrom5eabda32001-04-12 23:34:34 +0000289 authctxt.local_user = local_user;
Damien Miller62cee002000-09-23 17:15:56 +1100290 authctxt.host = host;
291 authctxt.service = "ssh-connection"; /* service name */
292 authctxt.success = 0;
Damien Miller874d77b2000-10-14 16:23:11 +1100293 authctxt.method = authmethod_lookup("none");
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000294 authctxt.authlist = NULL;
Darren Tucker0efd1552003-08-26 11:49:55 +1000295 authctxt.methoddata = NULL;
Ben Lindstrom1bad2562002-06-06 19:57:33 +0000296 authctxt.sensitive = sensitive;
Ben Lindstrom7d199962001-09-12 18:29:00 +0000297 authctxt.info_req_seen = 0;
Damien Miller874d77b2000-10-14 16:23:11 +1100298 if (authctxt.method == NULL)
299 fatal("ssh_userauth2: internal error: cannot send userauth none request");
Damien Miller62cee002000-09-23 17:15:56 +1100300
301 /* initial userauth request */
Damien Miller874d77b2000-10-14 16:23:11 +1100302 userauth_none(&authctxt);
Damien Miller62cee002000-09-23 17:15:56 +1100303
Ben Lindstrom8ac91062001-04-04 17:57:54 +0000304 dispatch_init(&input_userauth_error);
Damien Miller62cee002000-09-23 17:15:56 +1100305 dispatch_set(SSH2_MSG_USERAUTH_SUCCESS, &input_userauth_success);
306 dispatch_set(SSH2_MSG_USERAUTH_FAILURE, &input_userauth_failure);
Ben Lindstromd26dcf32001-01-06 15:18:16 +0000307 dispatch_set(SSH2_MSG_USERAUTH_BANNER, &input_userauth_banner);
Damien Miller62cee002000-09-23 17:15:56 +1100308 dispatch_run(DISPATCH_BLOCK, &authctxt.success, &authctxt); /* loop until success */
309
Damien Miller280ecfb2003-05-14 13:46:00 +1000310 pubkey_cleanup(&authctxt);
Damien Millerf842fcb2003-05-15 12:01:28 +1000311 dispatch_range(SSH2_MSG_USERAUTH_MIN, SSH2_MSG_USERAUTH_MAX, NULL);
312
Ben Lindstrom1d568f92002-12-23 02:44:36 +0000313 debug("Authentication succeeded (%s).", authctxt.method->name);
Damien Miller62cee002000-09-23 17:15:56 +1100314}
Damien Millerf842fcb2003-05-15 12:01:28 +1000315
Damien Miller62cee002000-09-23 17:15:56 +1100316void
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000317userauth(Authctxt *authctxt, char *authlist)
318{
Darren Tucker0efd1552003-08-26 11:49:55 +1000319 if (authctxt->methoddata) {
320 xfree(authctxt->methoddata);
321 authctxt->methoddata = NULL;
322 }
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000323 if (authlist == NULL) {
324 authlist = authctxt->authlist;
325 } else {
326 if (authctxt->authlist)
327 xfree(authctxt->authlist);
328 authctxt->authlist = authlist;
329 }
330 for (;;) {
331 Authmethod *method = authmethod_get(authlist);
332 if (method == NULL)
333 fatal("Permission denied (%s).", authlist);
334 authctxt->method = method;
Damien Millerf842fcb2003-05-15 12:01:28 +1000335
336 /* reset the per method handler */
337 dispatch_range(SSH2_MSG_USERAUTH_PER_METHOD_MIN,
338 SSH2_MSG_USERAUTH_PER_METHOD_MAX, NULL);
339
340 /* and try new method */
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000341 if (method->userauth(authctxt) != 0) {
342 debug2("we sent a %s packet, wait for reply", method->name);
343 break;
344 } else {
345 debug2("we did not send a packet, disable method");
346 method->enabled = NULL;
347 }
348 }
349}
Ben Lindstrom5c385522002-06-23 21:23:20 +0000350
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000351void
Damien Miller630d6f42002-01-22 23:17:30 +1100352input_userauth_error(int type, u_int32_t seq, void *ctxt)
Damien Miller62cee002000-09-23 17:15:56 +1100353{
Ben Lindstromd26dcf32001-01-06 15:18:16 +0000354 fatal("input_userauth_error: bad message during authentication: "
355 "type %d", type);
356}
Ben Lindstrom5c385522002-06-23 21:23:20 +0000357
Ben Lindstromd26dcf32001-01-06 15:18:16 +0000358void
Damien Miller630d6f42002-01-22 23:17:30 +1100359input_userauth_banner(int type, u_int32_t seq, void *ctxt)
Ben Lindstromd26dcf32001-01-06 15:18:16 +0000360{
361 char *msg, *lang;
Darren Tucker79644822003-10-08 17:37:58 +1000362
Ben Lindstromd26dcf32001-01-06 15:18:16 +0000363 debug3("input_userauth_banner");
364 msg = packet_get_string(NULL);
365 lang = packet_get_string(NULL);
Darren Tucker046dff22003-10-08 17:32:02 +1000366 if (options.log_level > SYSLOG_LEVEL_QUIET)
367 fprintf(stderr, "%s", msg);
Ben Lindstromd26dcf32001-01-06 15:18:16 +0000368 xfree(msg);
369 xfree(lang);
Damien Miller62cee002000-09-23 17:15:56 +1100370}
Ben Lindstrom5c385522002-06-23 21:23:20 +0000371
Damien Miller62cee002000-09-23 17:15:56 +1100372void
Damien Miller630d6f42002-01-22 23:17:30 +1100373input_userauth_success(int type, u_int32_t seq, void *ctxt)
Damien Miller62cee002000-09-23 17:15:56 +1100374{
375 Authctxt *authctxt = ctxt;
376 if (authctxt == NULL)
377 fatal("input_userauth_success: no authentication context");
Darren Tucker79644822003-10-08 17:37:58 +1000378 if (authctxt->authlist) {
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000379 xfree(authctxt->authlist);
Darren Tucker79644822003-10-08 17:37:58 +1000380 authctxt->authlist = NULL;
381 }
382 if (authctxt->methoddata) {
Darren Tucker0efd1552003-08-26 11:49:55 +1000383 xfree(authctxt->methoddata);
Darren Tucker79644822003-10-08 17:37:58 +1000384 authctxt->methoddata = NULL;
385 }
Damien Miller62cee002000-09-23 17:15:56 +1100386 authctxt->success = 1; /* break out */
387}
Ben Lindstrom5c385522002-06-23 21:23:20 +0000388
Damien Miller62cee002000-09-23 17:15:56 +1100389void
Damien Miller630d6f42002-01-22 23:17:30 +1100390input_userauth_failure(int type, u_int32_t seq, void *ctxt)
Damien Miller62cee002000-09-23 17:15:56 +1100391{
Damien Miller62cee002000-09-23 17:15:56 +1100392 Authctxt *authctxt = ctxt;
393 char *authlist = NULL;
394 int partial;
Damien Miller62cee002000-09-23 17:15:56 +1100395
396 if (authctxt == NULL)
397 fatal("input_userauth_failure: no authentication context");
398
Damien Miller874d77b2000-10-14 16:23:11 +1100399 authlist = packet_get_string(NULL);
Damien Miller62cee002000-09-23 17:15:56 +1100400 partial = packet_get_char();
Damien Miller48b03fc2002-01-22 23:11:40 +1100401 packet_check_eom();
Damien Miller62cee002000-09-23 17:15:56 +1100402
403 if (partial != 0)
Damien Miller996acd22003-04-09 20:59:48 +1000404 logit("Authenticated with partial success.");
Ben Lindstrom1d568f92002-12-23 02:44:36 +0000405 debug("Authentications that can continue: %s", authlist);
Damien Miller62cee002000-09-23 17:15:56 +1100406
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000407 userauth(authctxt, authlist);
408}
409void
Damien Miller630d6f42002-01-22 23:17:30 +1100410input_userauth_pk_ok(int type, u_int32_t seq, void *ctxt)
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000411{
412 Authctxt *authctxt = ctxt;
413 Key *key = NULL;
Damien Miller280ecfb2003-05-14 13:46:00 +1000414 Identity *id = NULL;
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000415 Buffer b;
Ben Lindstrom90fd8142002-02-26 18:09:42 +0000416 int pktype, sent = 0;
417 u_int alen, blen;
418 char *pkalg, *fp;
419 u_char *pkblob;
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000420
421 if (authctxt == NULL)
422 fatal("input_userauth_pk_ok: no authentication context");
423 if (datafellows & SSH_BUG_PKOK) {
424 /* this is similar to SSH_BUG_PKAUTH */
425 debug2("input_userauth_pk_ok: SSH_BUG_PKOK");
426 pkblob = packet_get_string(&blen);
427 buffer_init(&b);
428 buffer_append(&b, pkblob, blen);
429 pkalg = buffer_get_string(&b, &alen);
430 buffer_free(&b);
431 } else {
432 pkalg = packet_get_string(&alen);
433 pkblob = packet_get_string(&blen);
Kevin Stevesef4eea92001-02-05 12:42:17 +0000434 }
Damien Miller48b03fc2002-01-22 23:11:40 +1100435 packet_check_eom();
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000436
Damien Miller280ecfb2003-05-14 13:46:00 +1000437 debug("Server accepts key: pkalg %s blen %u", pkalg, blen);
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000438
Damien Miller280ecfb2003-05-14 13:46:00 +1000439 if ((pktype = key_type_from_name(pkalg)) == KEY_UNSPEC) {
440 debug("unknown pkalg %s", pkalg);
441 goto done;
442 }
443 if ((key = key_from_blob(pkblob, blen)) == NULL) {
444 debug("no key from blob. pkalg %s", pkalg);
445 goto done;
446 }
447 if (key->type != pktype) {
448 error("input_userauth_pk_ok: type mismatch "
449 "for decoded key (received %d, expected %d)",
450 key->type, pktype);
451 goto done;
452 }
453 fp = key_fingerprint(key, SSH_FP_MD5, SSH_FP_HEX);
454 debug2("input_userauth_pk_ok: fp %s", fp);
455 xfree(fp);
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000456
Darren Tuckerd05b6012003-10-15 15:55:59 +1000457 /*
458 * search keys in the reverse order, because last candidate has been
459 * moved to the end of the queue. this also avoids confusion by
460 * duplicate keys
461 */
Damien Miller0b51a522004-04-20 20:07:19 +1000462 TAILQ_FOREACH_REVERSE(id, &authctxt->keys, idlist, next) {
Damien Miller280ecfb2003-05-14 13:46:00 +1000463 if (key_equal(key, id->key)) {
464 sent = sign_and_send_pubkey(authctxt, id);
465 break;
466 }
467 }
468done:
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000469 if (key != NULL)
470 key_free(key);
471 xfree(pkalg);
472 xfree(pkblob);
473
Ben Lindstroma962c2f2002-07-04 00:14:17 +0000474 /* try another method if we did not send a packet */
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000475 if (sent == 0)
476 userauth(authctxt, NULL);
Damien Miller62cee002000-09-23 17:15:56 +1100477}
478
Darren Tucker0efd1552003-08-26 11:49:55 +1000479#ifdef GSSAPI
Damien Millera8e06ce2003-11-21 23:48:55 +1100480int
Darren Tucker0efd1552003-08-26 11:49:55 +1000481userauth_gssapi(Authctxt *authctxt)
482{
483 Gssctxt *gssctxt = NULL;
Darren Tucker56afe142003-11-03 20:06:14 +1100484 static gss_OID_set gss_supported = NULL;
Darren Tucker0efd1552003-08-26 11:49:55 +1000485 static int mech = 0;
486 OM_uint32 min;
487 int ok = 0;
488
489 /* Try one GSSAPI method at a time, rather than sending them all at
490 * once. */
491
Darren Tucker56afe142003-11-03 20:06:14 +1100492 if (gss_supported == NULL)
493 gss_indicate_mechs(&min, &gss_supported);
Darren Tucker0efd1552003-08-26 11:49:55 +1000494
495 /* Check to see if the mechanism is usable before we offer it */
Darren Tucker56afe142003-11-03 20:06:14 +1100496 while (mech < gss_supported->count && !ok) {
Darren Tucker0efd1552003-08-26 11:49:55 +1000497 if (gssctxt)
498 ssh_gssapi_delete_ctx(&gssctxt);
499 ssh_gssapi_build_ctx(&gssctxt);
Darren Tucker56afe142003-11-03 20:06:14 +1100500 ssh_gssapi_set_oid(gssctxt, &gss_supported->elements[mech]);
Darren Tucker0efd1552003-08-26 11:49:55 +1000501
502 /* My DER encoding requires length<128 */
Darren Tucker56afe142003-11-03 20:06:14 +1100503 if (gss_supported->elements[mech].length < 128 &&
Darren Tucker0efd1552003-08-26 11:49:55 +1000504 !GSS_ERROR(ssh_gssapi_import_name(gssctxt,
505 authctxt->host))) {
506 ok = 1; /* Mechanism works */
507 } else {
508 mech++;
509 }
510 }
511
512 if (!ok) return 0;
513
514 authctxt->methoddata=(void *)gssctxt;
515
516 packet_start(SSH2_MSG_USERAUTH_REQUEST);
517 packet_put_cstring(authctxt->server_user);
518 packet_put_cstring(authctxt->service);
519 packet_put_cstring(authctxt->method->name);
520
521 packet_put_int(1);
522
Darren Tucker655a5e02003-11-03 20:09:03 +1100523 packet_put_int((gss_supported->elements[mech].length) + 2);
524 packet_put_char(SSH_GSS_OIDTYPE);
525 packet_put_char(gss_supported->elements[mech].length);
526 packet_put_raw(gss_supported->elements[mech].elements,
527 gss_supported->elements[mech].length);
Darren Tucker0efd1552003-08-26 11:49:55 +1000528
529 packet_send();
530
531 dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_RESPONSE, &input_gssapi_response);
532 dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, &input_gssapi_token);
533 dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERROR, &input_gssapi_error);
534 dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK, &input_gssapi_errtok);
535
536 mech++; /* Move along to next candidate */
537
538 return 1;
539}
540
Damien Miller91c6aa42003-11-17 21:20:18 +1100541static OM_uint32
542process_gssapi_token(void *ctxt, gss_buffer_t recv_tok)
543{
544 Authctxt *authctxt = ctxt;
545 Gssctxt *gssctxt = authctxt->methoddata;
546 gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
Damien Miller0425d402003-11-17 22:18:21 +1100547 gss_buffer_desc gssbuf, mic;
548 OM_uint32 status, ms, flags;
549 Buffer b;
Damien Miller787b2ec2003-11-21 23:56:47 +1100550
Damien Miller91c6aa42003-11-17 21:20:18 +1100551 status = ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
Damien Miller0425d402003-11-17 22:18:21 +1100552 recv_tok, &send_tok, &flags);
Damien Miller91c6aa42003-11-17 21:20:18 +1100553
554 if (send_tok.length > 0) {
555 if (GSS_ERROR(status))
556 packet_start(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK);
557 else
558 packet_start(SSH2_MSG_USERAUTH_GSSAPI_TOKEN);
Damien Miller787b2ec2003-11-21 23:56:47 +1100559
Damien Miller91c6aa42003-11-17 21:20:18 +1100560 packet_put_string(send_tok.value, send_tok.length);
561 packet_send();
562 gss_release_buffer(&ms, &send_tok);
563 }
Damien Miller787b2ec2003-11-21 23:56:47 +1100564
Damien Miller91c6aa42003-11-17 21:20:18 +1100565 if (status == GSS_S_COMPLETE) {
Damien Miller0425d402003-11-17 22:18:21 +1100566 /* send either complete or MIC, depending on mechanism */
567 if (!(flags & GSS_C_INTEG_FLAG)) {
568 packet_start(SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE);
569 packet_send();
570 } else {
571 ssh_gssapi_buildmic(&b, authctxt->server_user,
572 authctxt->service, "gssapi-with-mic");
573
574 gssbuf.value = buffer_ptr(&b);
575 gssbuf.length = buffer_len(&b);
Damien Miller787b2ec2003-11-21 23:56:47 +1100576
Damien Miller0425d402003-11-17 22:18:21 +1100577 status = ssh_gssapi_sign(gssctxt, &gssbuf, &mic);
Damien Miller787b2ec2003-11-21 23:56:47 +1100578
Damien Miller0425d402003-11-17 22:18:21 +1100579 if (!GSS_ERROR(status)) {
580 packet_start(SSH2_MSG_USERAUTH_GSSAPI_MIC);
581 packet_put_string(mic.value, mic.length);
Damien Miller787b2ec2003-11-21 23:56:47 +1100582
Damien Miller0425d402003-11-17 22:18:21 +1100583 packet_send();
584 }
Damien Miller787b2ec2003-11-21 23:56:47 +1100585
Damien Miller0425d402003-11-17 22:18:21 +1100586 buffer_free(&b);
587 gss_release_buffer(&ms, &mic);
Damien Miller787b2ec2003-11-21 23:56:47 +1100588 }
Damien Miller91c6aa42003-11-17 21:20:18 +1100589 }
Damien Miller787b2ec2003-11-21 23:56:47 +1100590
Damien Miller91c6aa42003-11-17 21:20:18 +1100591 return status;
592}
593
Darren Tucker0efd1552003-08-26 11:49:55 +1000594void
595input_gssapi_response(int type, u_int32_t plen, void *ctxt)
596{
597 Authctxt *authctxt = ctxt;
598 Gssctxt *gssctxt;
Darren Tucker0efd1552003-08-26 11:49:55 +1000599 int oidlen;
600 char *oidv;
Darren Tucker0efd1552003-08-26 11:49:55 +1000601
602 if (authctxt == NULL)
603 fatal("input_gssapi_response: no authentication context");
604 gssctxt = authctxt->methoddata;
605
606 /* Setup our OID */
607 oidv = packet_get_string(&oidlen);
608
Darren Tucker655a5e02003-11-03 20:09:03 +1100609 if (oidlen <= 2 ||
610 oidv[0] != SSH_GSS_OIDTYPE ||
611 oidv[1] != oidlen - 2) {
Damien Miller91c6aa42003-11-17 21:20:18 +1100612 xfree(oidv);
Darren Tucker655a5e02003-11-03 20:09:03 +1100613 debug("Badly encoded mechanism OID received");
614 userauth(authctxt, NULL);
Darren Tucker655a5e02003-11-03 20:09:03 +1100615 return;
Darren Tucker0efd1552003-08-26 11:49:55 +1000616 }
617
Darren Tucker655a5e02003-11-03 20:09:03 +1100618 if (!ssh_gssapi_check_oid(gssctxt, oidv + 2, oidlen - 2))
619 fatal("Server returned different OID than expected");
620
Darren Tucker0efd1552003-08-26 11:49:55 +1000621 packet_check_eom();
622
623 xfree(oidv);
624
Damien Miller91c6aa42003-11-17 21:20:18 +1100625 if (GSS_ERROR(process_gssapi_token(ctxt, GSS_C_NO_BUFFER))) {
Darren Tucker0efd1552003-08-26 11:49:55 +1000626 /* Start again with next method on list */
627 debug("Trying to start again");
628 userauth(authctxt, NULL);
629 return;
630 }
Darren Tucker0efd1552003-08-26 11:49:55 +1000631}
632
633void
634input_gssapi_token(int type, u_int32_t plen, void *ctxt)
635{
636 Authctxt *authctxt = ctxt;
Darren Tucker0efd1552003-08-26 11:49:55 +1000637 gss_buffer_desc recv_tok;
Damien Miller91c6aa42003-11-17 21:20:18 +1100638 OM_uint32 status;
Darren Tucker0efd1552003-08-26 11:49:55 +1000639 u_int slen;
640
641 if (authctxt == NULL)
642 fatal("input_gssapi_response: no authentication context");
Darren Tucker0efd1552003-08-26 11:49:55 +1000643
644 recv_tok.value = packet_get_string(&slen);
645 recv_tok.length = slen; /* safe typecast */
646
647 packet_check_eom();
648
Damien Miller91c6aa42003-11-17 21:20:18 +1100649 status = process_gssapi_token(ctxt, &recv_tok);
Darren Tucker0efd1552003-08-26 11:49:55 +1000650
651 xfree(recv_tok.value);
652
653 if (GSS_ERROR(status)) {
Darren Tucker0efd1552003-08-26 11:49:55 +1000654 /* Start again with the next method in the list */
655 userauth(authctxt, NULL);
656 return;
657 }
Darren Tucker0efd1552003-08-26 11:49:55 +1000658}
659
660void
661input_gssapi_errtok(int type, u_int32_t plen, void *ctxt)
662{
663 Authctxt *authctxt = ctxt;
664 Gssctxt *gssctxt;
665 gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
666 gss_buffer_desc recv_tok;
667 OM_uint32 status, ms;
Darren Tucker600ad8d2003-08-26 12:10:48 +1000668 u_int len;
Darren Tucker0efd1552003-08-26 11:49:55 +1000669
670 if (authctxt == NULL)
671 fatal("input_gssapi_response: no authentication context");
672 gssctxt = authctxt->methoddata;
673
Darren Tucker600ad8d2003-08-26 12:10:48 +1000674 recv_tok.value = packet_get_string(&len);
675 recv_tok.length = len;
Darren Tucker0efd1552003-08-26 11:49:55 +1000676
677 packet_check_eom();
678
679 /* Stick it into GSSAPI and see what it says */
680 status = ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
681 &recv_tok, &send_tok, NULL);
682
683 xfree(recv_tok.value);
684 gss_release_buffer(&ms, &send_tok);
685
686 /* Server will be returning a failed packet after this one */
687}
688
689void
690input_gssapi_error(int type, u_int32_t plen, void *ctxt)
691{
692 OM_uint32 maj, min;
693 char *msg;
694 char *lang;
695
696 maj=packet_get_int();
697 min=packet_get_int();
698 msg=packet_get_string(NULL);
699 lang=packet_get_string(NULL);
700
701 packet_check_eom();
702
703 debug("Server GSSAPI Error:\n%s\n", msg);
704 xfree(msg);
705 xfree(lang);
706}
707#endif /* GSSAPI */
708
Damien Millereba71ba2000-04-29 23:57:08 +1000709int
Damien Miller874d77b2000-10-14 16:23:11 +1100710userauth_none(Authctxt *authctxt)
711{
712 /* initial userauth request */
713 packet_start(SSH2_MSG_USERAUTH_REQUEST);
714 packet_put_cstring(authctxt->server_user);
715 packet_put_cstring(authctxt->service);
716 packet_put_cstring(authctxt->method->name);
717 packet_send();
Damien Miller874d77b2000-10-14 16:23:11 +1100718 return 1;
719}
720
721int
Damien Miller62cee002000-09-23 17:15:56 +1100722userauth_passwd(Authctxt *authctxt)
Damien Millereba71ba2000-04-29 23:57:08 +1000723{
Damien Millere247cc42000-05-07 12:03:14 +1000724 static int attempt = 0;
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000725 char prompt[150];
Damien Millereba71ba2000-04-29 23:57:08 +1000726 char *password;
727
Damien Millerd3a18572000-06-07 19:55:44 +1000728 if (attempt++ >= options.number_of_password_prompts)
Damien Millere247cc42000-05-07 12:03:14 +1000729 return 0;
730
Ben Lindstrom1c37c6a2001-12-06 18:00:18 +0000731 if (attempt != 1)
Damien Millerd3a18572000-06-07 19:55:44 +1000732 error("Permission denied, please try again.");
733
Ben Lindstrom03df5bd2001-02-10 22:16:41 +0000734 snprintf(prompt, sizeof(prompt), "%.30s@%.128s's password: ",
Damien Miller62cee002000-09-23 17:15:56 +1100735 authctxt->server_user, authctxt->host);
Damien Millereba71ba2000-04-29 23:57:08 +1000736 password = read_passphrase(prompt, 0);
737 packet_start(SSH2_MSG_USERAUTH_REQUEST);
Damien Miller62cee002000-09-23 17:15:56 +1100738 packet_put_cstring(authctxt->server_user);
739 packet_put_cstring(authctxt->service);
Damien Miller874d77b2000-10-14 16:23:11 +1100740 packet_put_cstring(authctxt->method->name);
Damien Millereba71ba2000-04-29 23:57:08 +1000741 packet_put_char(0);
Ben Lindstrom5699c5f2001-03-05 06:17:49 +0000742 packet_put_cstring(password);
Damien Millereba71ba2000-04-29 23:57:08 +1000743 memset(password, 0, strlen(password));
744 xfree(password);
Damien Miller9f643902001-11-12 11:02:52 +1100745 packet_add_padding(64);
Damien Millereba71ba2000-04-29 23:57:08 +1000746 packet_send();
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000747
Ben Lindstromcb72e4f2002-06-21 00:41:51 +0000748 dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000749 &input_userauth_passwd_changereq);
750
Damien Millereba71ba2000-04-29 23:57:08 +1000751 return 1;
752}
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000753/*
754 * parse PASSWD_CHANGEREQ, prompt user and send SSH2_MSG_USERAUTH_REQUEST
755 */
756void
Tim Ricec8549622002-03-31 12:49:38 -0800757input_userauth_passwd_changereq(int type, u_int32_t seqnr, void *ctxt)
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000758{
759 Authctxt *authctxt = ctxt;
760 char *info, *lang, *password = NULL, *retype = NULL;
761 char prompt[150];
762
763 debug2("input_userauth_passwd_changereq");
764
765 if (authctxt == NULL)
766 fatal("input_userauth_passwd_changereq: "
767 "no authentication context");
768
769 info = packet_get_string(NULL);
770 lang = packet_get_string(NULL);
771 if (strlen(info) > 0)
Damien Miller996acd22003-04-09 20:59:48 +1000772 logit("%s", info);
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000773 xfree(info);
774 xfree(lang);
775 packet_start(SSH2_MSG_USERAUTH_REQUEST);
776 packet_put_cstring(authctxt->server_user);
777 packet_put_cstring(authctxt->service);
778 packet_put_cstring(authctxt->method->name);
779 packet_put_char(1); /* additional info */
Ben Lindstromcb72e4f2002-06-21 00:41:51 +0000780 snprintf(prompt, sizeof(prompt),
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000781 "Enter %.30s@%.128s's old password: ",
782 authctxt->server_user, authctxt->host);
783 password = read_passphrase(prompt, 0);
784 packet_put_cstring(password);
785 memset(password, 0, strlen(password));
786 xfree(password);
787 password = NULL;
788 while (password == NULL) {
Ben Lindstromcb72e4f2002-06-21 00:41:51 +0000789 snprintf(prompt, sizeof(prompt),
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000790 "Enter %.30s@%.128s's new password: ",
791 authctxt->server_user, authctxt->host);
792 password = read_passphrase(prompt, RP_ALLOW_EOF);
793 if (password == NULL) {
794 /* bail out */
795 return;
796 }
Ben Lindstromcb72e4f2002-06-21 00:41:51 +0000797 snprintf(prompt, sizeof(prompt),
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000798 "Retype %.30s@%.128s's new password: ",
799 authctxt->server_user, authctxt->host);
800 retype = read_passphrase(prompt, 0);
801 if (strcmp(password, retype) != 0) {
802 memset(password, 0, strlen(password));
803 xfree(password);
Damien Miller996acd22003-04-09 20:59:48 +1000804 logit("Mismatch; try again, EOF to quit.");
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000805 password = NULL;
806 }
807 memset(retype, 0, strlen(retype));
808 xfree(retype);
809 }
810 packet_put_cstring(password);
811 memset(password, 0, strlen(password));
812 xfree(password);
813 packet_add_padding(64);
814 packet_send();
Ben Lindstromcb72e4f2002-06-21 00:41:51 +0000815
816 dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000817 &input_userauth_passwd_changereq);
818}
Damien Millereba71ba2000-04-29 23:57:08 +1000819
Ben Lindstrombba81212001-06-25 05:01:22 +0000820static int
Damien Miller280ecfb2003-05-14 13:46:00 +1000821identity_sign(Identity *id, u_char **sigp, u_int *lenp,
822 u_char *data, u_int datalen)
823{
824 Key *prv;
825 int ret;
826
827 /* the agent supports this key */
828 if (id->ac)
829 return (ssh_agent_sign(id->ac, id->key, sigp, lenp,
830 data, datalen));
831 /*
832 * we have already loaded the private key or
833 * the private key is stored in external hardware
834 */
835 if (id->isprivate || (id->key->flags & KEY_FLAG_EXT))
836 return (key_sign(id->key, sigp, lenp, data, datalen));
837 /* load the private key from the file */
838 if ((prv = load_identity_file(id->filename)) == NULL)
839 return (-1);
840 ret = key_sign(prv, sigp, lenp, data, datalen);
841 key_free(prv);
842 return (ret);
843}
844
845static int
846sign_and_send_pubkey(Authctxt *authctxt, Identity *id)
Damien Millereba71ba2000-04-29 23:57:08 +1000847{
848 Buffer b;
Ben Lindstrom46c16222000-12-22 01:43:59 +0000849 u_char *blob, *signature;
Ben Lindstrom90fd8142002-02-26 18:09:42 +0000850 u_int bloblen, slen;
Darren Tucker502d3842003-06-28 12:38:01 +1000851 u_int skip = 0;
Damien Millerad833b32000-08-23 10:46:23 +1000852 int ret = -1;
Damien Miller874d77b2000-10-14 16:23:11 +1100853 int have_sig = 1;
Damien Millereba71ba2000-04-29 23:57:08 +1000854
Ben Lindstromd121f612000-12-03 17:00:47 +0000855 debug3("sign_and_send_pubkey");
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000856
Damien Miller280ecfb2003-05-14 13:46:00 +1000857 if (key_to_blob(id->key, &blob, &bloblen) == 0) {
Damien Miller0bc1bd82000-11-13 22:57:25 +1100858 /* we cannot handle this key */
Ben Lindstromd121f612000-12-03 17:00:47 +0000859 debug3("sign_and_send_pubkey: cannot handle key");
Damien Miller0bc1bd82000-11-13 22:57:25 +1100860 return 0;
861 }
Damien Millereba71ba2000-04-29 23:57:08 +1000862 /* data to be signed */
863 buffer_init(&b);
Damien Miller50a41ed2000-10-16 12:14:42 +1100864 if (datafellows & SSH_OLD_SESSIONID) {
Damien Miller6536c7d2000-06-22 21:32:31 +1000865 buffer_append(&b, session_id2, session_id2_len);
Kevin Stevesef4eea92001-02-05 12:42:17 +0000866 skip = session_id2_len;
Damien Miller50a41ed2000-10-16 12:14:42 +1100867 } else {
868 buffer_put_string(&b, session_id2, session_id2_len);
869 skip = buffer_len(&b);
Damien Miller6536c7d2000-06-22 21:32:31 +1000870 }
Damien Millereba71ba2000-04-29 23:57:08 +1000871 buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
Damien Miller62cee002000-09-23 17:15:56 +1100872 buffer_put_cstring(&b, authctxt->server_user);
Damien Miller30c3d422000-05-09 11:02:59 +1000873 buffer_put_cstring(&b,
Ben Lindstromd121f612000-12-03 17:00:47 +0000874 datafellows & SSH_BUG_PKSERVICE ?
Damien Miller30c3d422000-05-09 11:02:59 +1000875 "ssh-userauth" :
Damien Miller62cee002000-09-23 17:15:56 +1100876 authctxt->service);
Ben Lindstromd121f612000-12-03 17:00:47 +0000877 if (datafellows & SSH_BUG_PKAUTH) {
878 buffer_put_char(&b, have_sig);
879 } else {
880 buffer_put_cstring(&b, authctxt->method->name);
881 buffer_put_char(&b, have_sig);
Damien Miller280ecfb2003-05-14 13:46:00 +1000882 buffer_put_cstring(&b, key_ssh_name(id->key));
Ben Lindstromd121f612000-12-03 17:00:47 +0000883 }
Damien Millereba71ba2000-04-29 23:57:08 +1000884 buffer_put_string(&b, blob, bloblen);
Damien Millereba71ba2000-04-29 23:57:08 +1000885
886 /* generate signature */
Damien Miller280ecfb2003-05-14 13:46:00 +1000887 ret = identity_sign(id, &signature, &slen,
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000888 buffer_ptr(&b), buffer_len(&b));
Damien Millerad833b32000-08-23 10:46:23 +1000889 if (ret == -1) {
890 xfree(blob);
891 buffer_free(&b);
892 return 0;
893 }
Damien Miller0bc1bd82000-11-13 22:57:25 +1100894#ifdef DEBUG_PK
Damien Millereba71ba2000-04-29 23:57:08 +1000895 buffer_dump(&b);
896#endif
Ben Lindstromd121f612000-12-03 17:00:47 +0000897 if (datafellows & SSH_BUG_PKSERVICE) {
Damien Miller30c3d422000-05-09 11:02:59 +1000898 buffer_clear(&b);
899 buffer_append(&b, session_id2, session_id2_len);
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000900 skip = session_id2_len;
Damien Miller30c3d422000-05-09 11:02:59 +1000901 buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
Damien Miller62cee002000-09-23 17:15:56 +1100902 buffer_put_cstring(&b, authctxt->server_user);
903 buffer_put_cstring(&b, authctxt->service);
Damien Miller874d77b2000-10-14 16:23:11 +1100904 buffer_put_cstring(&b, authctxt->method->name);
905 buffer_put_char(&b, have_sig);
Ben Lindstromd121f612000-12-03 17:00:47 +0000906 if (!(datafellows & SSH_BUG_PKAUTH))
Damien Miller280ecfb2003-05-14 13:46:00 +1000907 buffer_put_cstring(&b, key_ssh_name(id->key));
Damien Miller30c3d422000-05-09 11:02:59 +1000908 buffer_put_string(&b, blob, bloblen);
909 }
910 xfree(blob);
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000911
Damien Millereba71ba2000-04-29 23:57:08 +1000912 /* append signature */
913 buffer_put_string(&b, signature, slen);
914 xfree(signature);
915
916 /* skip session id and packet type */
Damien Miller6536c7d2000-06-22 21:32:31 +1000917 if (buffer_len(&b) < skip + 1)
Damien Miller62cee002000-09-23 17:15:56 +1100918 fatal("userauth_pubkey: internal error");
Damien Miller6536c7d2000-06-22 21:32:31 +1000919 buffer_consume(&b, skip + 1);
Damien Millereba71ba2000-04-29 23:57:08 +1000920
921 /* put remaining data from buffer into packet */
922 packet_start(SSH2_MSG_USERAUTH_REQUEST);
923 packet_put_raw(buffer_ptr(&b), buffer_len(&b));
924 buffer_free(&b);
Damien Millereba71ba2000-04-29 23:57:08 +1000925 packet_send();
Damien Millerad833b32000-08-23 10:46:23 +1000926
927 return 1;
Damien Miller994cf142000-07-21 10:19:44 +1000928}
929
Ben Lindstrombba81212001-06-25 05:01:22 +0000930static int
Damien Miller280ecfb2003-05-14 13:46:00 +1000931send_pubkey_test(Authctxt *authctxt, Identity *id)
Damien Miller994cf142000-07-21 10:19:44 +1000932{
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000933 u_char *blob;
Ben Lindstromc58ab022002-02-26 18:15:09 +0000934 u_int bloblen, have_sig = 0;
Damien Miller994cf142000-07-21 10:19:44 +1000935
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000936 debug3("send_pubkey_test");
937
Damien Miller280ecfb2003-05-14 13:46:00 +1000938 if (key_to_blob(id->key, &blob, &bloblen) == 0) {
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000939 /* we cannot handle this key */
940 debug3("send_pubkey_test: cannot handle key");
Damien Miller994cf142000-07-21 10:19:44 +1000941 return 0;
942 }
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000943 /* register callback for USERAUTH_PK_OK message */
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000944 dispatch_set(SSH2_MSG_USERAUTH_PK_OK, &input_userauth_pk_ok);
Damien Miller994cf142000-07-21 10:19:44 +1000945
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000946 packet_start(SSH2_MSG_USERAUTH_REQUEST);
947 packet_put_cstring(authctxt->server_user);
948 packet_put_cstring(authctxt->service);
949 packet_put_cstring(authctxt->method->name);
950 packet_put_char(have_sig);
951 if (!(datafellows & SSH_BUG_PKAUTH))
Damien Miller280ecfb2003-05-14 13:46:00 +1000952 packet_put_cstring(key_ssh_name(id->key));
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000953 packet_put_string(blob, bloblen);
954 xfree(blob);
955 packet_send();
956 return 1;
957}
958
Ben Lindstrombba81212001-06-25 05:01:22 +0000959static Key *
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000960load_identity_file(char *filename)
961{
962 Key *private;
963 char prompt[300], *passphrase;
Ben Lindstromd0fca422001-03-26 13:44:06 +0000964 int quit, i;
Ben Lindstrom329782e2001-03-10 17:08:59 +0000965 struct stat st;
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000966
Ben Lindstrom329782e2001-03-10 17:08:59 +0000967 if (stat(filename, &st) < 0) {
968 debug3("no such identity: %s", filename);
969 return NULL;
970 }
Ben Lindstromd0fca422001-03-26 13:44:06 +0000971 private = key_load_private_type(KEY_UNSPEC, filename, "", NULL);
972 if (private == NULL) {
973 if (options.batch_mode)
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000974 return NULL;
Damien Miller994cf142000-07-21 10:19:44 +1000975 snprintf(prompt, sizeof prompt,
Damien Miller9f0f5c62001-12-21 14:45:46 +1100976 "Enter passphrase for key '%.100s': ", filename);
Damien Miller62cee002000-09-23 17:15:56 +1100977 for (i = 0; i < options.number_of_password_prompts; i++) {
978 passphrase = read_passphrase(prompt, 0);
979 if (strcmp(passphrase, "") != 0) {
Ben Lindstromd0fca422001-03-26 13:44:06 +0000980 private = key_load_private_type(KEY_UNSPEC, filename,
981 passphrase, NULL);
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000982 quit = 0;
Damien Miller62cee002000-09-23 17:15:56 +1100983 } else {
984 debug2("no passphrase given, try next key");
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000985 quit = 1;
Damien Miller62cee002000-09-23 17:15:56 +1100986 }
987 memset(passphrase, 0, strlen(passphrase));
988 xfree(passphrase);
Ben Lindstromd0fca422001-03-26 13:44:06 +0000989 if (private != NULL || quit)
Damien Miller62cee002000-09-23 17:15:56 +1100990 break;
991 debug2("bad passphrase given, try again...");
992 }
Damien Miller994cf142000-07-21 10:19:44 +1000993 }
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000994 return private;
995}
996
Damien Miller280ecfb2003-05-14 13:46:00 +1000997/*
998 * try keys in the following order:
999 * 1. agent keys that are found in the config file
1000 * 2. other agent keys
1001 * 3. keys that are only listed in the config file
1002 */
1003static void
1004pubkey_prepare(Authctxt *authctxt)
Ben Lindstrom266dfdf2001-03-09 00:12:22 +00001005{
Damien Miller280ecfb2003-05-14 13:46:00 +10001006 Identity *id;
1007 Idlist agent, files, *preferred;
1008 Key *key;
1009 AuthenticationConnection *ac;
Damien Millerad833b32000-08-23 10:46:23 +10001010 char *comment;
Damien Miller280ecfb2003-05-14 13:46:00 +10001011 int i, found;
Damien Millerad833b32000-08-23 10:46:23 +10001012
Damien Miller280ecfb2003-05-14 13:46:00 +10001013 TAILQ_INIT(&agent); /* keys from the agent */
1014 TAILQ_INIT(&files); /* keys from the config file */
1015 preferred = &authctxt->keys;
1016 TAILQ_INIT(preferred); /* preferred order of keys */
1017
1018 /* list of keys stored in the filesystem */
1019 for (i = 0; i < options.num_identity_files; i++) {
1020 key = options.identity_keys[i];
1021 if (key && key->type == KEY_RSA1)
1022 continue;
1023 options.identity_keys[i] = NULL;
1024 id = xmalloc(sizeof(*id));
1025 memset(id, 0, sizeof(*id));
1026 id->key = key;
1027 id->filename = xstrdup(options.identity_files[i]);
1028 TAILQ_INSERT_TAIL(&files, id, next);
Damien Millerad833b32000-08-23 10:46:23 +10001029 }
Damien Miller280ecfb2003-05-14 13:46:00 +10001030 /* list of keys supported by the agent */
1031 if ((ac = ssh_get_authentication_connection())) {
1032 for (key = ssh_get_first_identity(ac, &comment, 2);
1033 key != NULL;
1034 key = ssh_get_next_identity(ac, &comment, 2)) {
1035 found = 0;
1036 TAILQ_FOREACH(id, &files, next) {
Damien Millera8e06ce2003-11-21 23:48:55 +11001037 /* agent keys from the config file are preferred */
Damien Miller280ecfb2003-05-14 13:46:00 +10001038 if (key_equal(key, id->key)) {
1039 key_free(key);
1040 xfree(comment);
1041 TAILQ_REMOVE(&files, id, next);
1042 TAILQ_INSERT_TAIL(preferred, id, next);
1043 id->ac = ac;
1044 found = 1;
1045 break;
1046 }
1047 }
Damien Millerbd394c32004-03-08 23:12:36 +11001048 if (!found && !options.identities_only) {
Damien Miller280ecfb2003-05-14 13:46:00 +10001049 id = xmalloc(sizeof(*id));
1050 memset(id, 0, sizeof(*id));
1051 id->key = key;
1052 id->filename = comment;
1053 id->ac = ac;
1054 TAILQ_INSERT_TAIL(&agent, id, next);
1055 }
1056 }
1057 /* append remaining agent keys */
1058 for (id = TAILQ_FIRST(&agent); id; id = TAILQ_FIRST(&agent)) {
1059 TAILQ_REMOVE(&agent, id, next);
1060 TAILQ_INSERT_TAIL(preferred, id, next);
1061 }
1062 authctxt->agent = ac;
Damien Miller62cee002000-09-23 17:15:56 +11001063 }
Damien Miller280ecfb2003-05-14 13:46:00 +10001064 /* append remaining keys from the config file */
1065 for (id = TAILQ_FIRST(&files); id; id = TAILQ_FIRST(&files)) {
1066 TAILQ_REMOVE(&files, id, next);
1067 TAILQ_INSERT_TAIL(preferred, id, next);
1068 }
1069 TAILQ_FOREACH(id, preferred, next) {
1070 debug2("key: %s (%p)", id->filename, id->key);
1071 }
1072}
1073
1074static void
1075pubkey_cleanup(Authctxt *authctxt)
1076{
1077 Identity *id;
1078
1079 if (authctxt->agent != NULL)
1080 ssh_close_authentication_connection(authctxt->agent);
1081 for (id = TAILQ_FIRST(&authctxt->keys); id;
1082 id = TAILQ_FIRST(&authctxt->keys)) {
1083 TAILQ_REMOVE(&authctxt->keys, id, next);
1084 if (id->key)
1085 key_free(id->key);
1086 if (id->filename)
1087 xfree(id->filename);
1088 xfree(id);
1089 }
Damien Millereba71ba2000-04-29 23:57:08 +10001090}
1091
Damien Miller62cee002000-09-23 17:15:56 +11001092int
1093userauth_pubkey(Authctxt *authctxt)
Damien Millereba71ba2000-04-29 23:57:08 +10001094{
Damien Miller280ecfb2003-05-14 13:46:00 +10001095 Identity *id;
Damien Miller62cee002000-09-23 17:15:56 +11001096 int sent = 0;
Damien Millereba71ba2000-04-29 23:57:08 +10001097
Damien Miller280ecfb2003-05-14 13:46:00 +10001098 while ((id = TAILQ_FIRST(&authctxt->keys))) {
1099 if (id->tried++)
1100 return (0);
Darren Tuckerd05b6012003-10-15 15:55:59 +10001101 /* move key to the end of the queue */
Damien Miller280ecfb2003-05-14 13:46:00 +10001102 TAILQ_REMOVE(&authctxt->keys, id, next);
1103 TAILQ_INSERT_TAIL(&authctxt->keys, id, next);
1104 /*
1105 * send a test message if we have the public key. for
1106 * encrypted keys we cannot do this and have to load the
1107 * private key instead
1108 */
1109 if (id->key && id->key->type != KEY_RSA1) {
1110 debug("Offering public key: %s", id->filename);
1111 sent = send_pubkey_test(authctxt, id);
1112 } else if (id->key == NULL) {
1113 debug("Trying private key: %s", id->filename);
1114 id->key = load_identity_file(id->filename);
1115 if (id->key != NULL) {
1116 id->isprivate = 1;
1117 sent = sign_and_send_pubkey(authctxt, id);
1118 key_free(id->key);
1119 id->key = NULL;
Ben Lindstrom266dfdf2001-03-09 00:12:22 +00001120 }
Ben Lindstrom266dfdf2001-03-09 00:12:22 +00001121 }
Damien Miller280ecfb2003-05-14 13:46:00 +10001122 if (sent)
1123 return (sent);
Damien Miller0bc1bd82000-11-13 22:57:25 +11001124 }
Damien Miller280ecfb2003-05-14 13:46:00 +10001125 return (0);
Damien Miller62cee002000-09-23 17:15:56 +11001126}
Damien Millereba71ba2000-04-29 23:57:08 +10001127
Damien Miller874d77b2000-10-14 16:23:11 +11001128/*
1129 * Send userauth request message specifying keyboard-interactive method.
1130 */
1131int
1132userauth_kbdint(Authctxt *authctxt)
1133{
1134 static int attempt = 0;
1135
1136 if (attempt++ >= options.number_of_password_prompts)
1137 return 0;
Ben Lindstrom7d199962001-09-12 18:29:00 +00001138 /* disable if no SSH2_MSG_USERAUTH_INFO_REQUEST has been seen */
1139 if (attempt > 1 && !authctxt->info_req_seen) {
1140 debug3("userauth_kbdint: disable: no info_req_seen");
1141 dispatch_set(SSH2_MSG_USERAUTH_INFO_REQUEST, NULL);
1142 return 0;
1143 }
Damien Miller874d77b2000-10-14 16:23:11 +11001144
1145 debug2("userauth_kbdint");
1146 packet_start(SSH2_MSG_USERAUTH_REQUEST);
1147 packet_put_cstring(authctxt->server_user);
1148 packet_put_cstring(authctxt->service);
1149 packet_put_cstring(authctxt->method->name);
1150 packet_put_cstring(""); /* lang */
1151 packet_put_cstring(options.kbd_interactive_devices ?
1152 options.kbd_interactive_devices : "");
1153 packet_send();
Damien Miller874d77b2000-10-14 16:23:11 +11001154
1155 dispatch_set(SSH2_MSG_USERAUTH_INFO_REQUEST, &input_userauth_info_req);
1156 return 1;
1157}
1158
1159/*
Ben Lindstrom03df5bd2001-02-10 22:16:41 +00001160 * parse INFO_REQUEST, prompt user and send INFO_RESPONSE
Damien Miller874d77b2000-10-14 16:23:11 +11001161 */
1162void
Damien Miller630d6f42002-01-22 23:17:30 +11001163input_userauth_info_req(int type, u_int32_t seq, void *ctxt)
Damien Miller874d77b2000-10-14 16:23:11 +11001164{
1165 Authctxt *authctxt = ctxt;
Ben Lindstrom03df5bd2001-02-10 22:16:41 +00001166 char *name, *inst, *lang, *prompt, *response;
Ben Lindstrom46c16222000-12-22 01:43:59 +00001167 u_int num_prompts, i;
Damien Miller874d77b2000-10-14 16:23:11 +11001168 int echo = 0;
1169
1170 debug2("input_userauth_info_req");
1171
1172 if (authctxt == NULL)
1173 fatal("input_userauth_info_req: no authentication context");
1174
Ben Lindstrom7d199962001-09-12 18:29:00 +00001175 authctxt->info_req_seen = 1;
1176
Damien Miller874d77b2000-10-14 16:23:11 +11001177 name = packet_get_string(NULL);
1178 inst = packet_get_string(NULL);
1179 lang = packet_get_string(NULL);
Damien Miller874d77b2000-10-14 16:23:11 +11001180 if (strlen(name) > 0)
Damien Miller996acd22003-04-09 20:59:48 +10001181 logit("%s", name);
Damien Miller874d77b2000-10-14 16:23:11 +11001182 if (strlen(inst) > 0)
Damien Miller996acd22003-04-09 20:59:48 +10001183 logit("%s", inst);
Ben Lindstrom03df5bd2001-02-10 22:16:41 +00001184 xfree(name);
Damien Miller874d77b2000-10-14 16:23:11 +11001185 xfree(inst);
Ben Lindstrom03df5bd2001-02-10 22:16:41 +00001186 xfree(lang);
Damien Miller874d77b2000-10-14 16:23:11 +11001187
1188 num_prompts = packet_get_int();
1189 /*
1190 * Begin to build info response packet based on prompts requested.
1191 * We commit to providing the correct number of responses, so if
1192 * further on we run into a problem that prevents this, we have to
1193 * be sure and clean this up and send a correct error response.
1194 */
1195 packet_start(SSH2_MSG_USERAUTH_INFO_RESPONSE);
1196 packet_put_int(num_prompts);
1197
Ben Lindstrom551ea372001-06-05 18:56:16 +00001198 debug2("input_userauth_info_req: num_prompts %d", num_prompts);
Damien Miller874d77b2000-10-14 16:23:11 +11001199 for (i = 0; i < num_prompts; i++) {
1200 prompt = packet_get_string(NULL);
1201 echo = packet_get_char();
1202
Ben Lindstrom949974b2001-06-25 05:20:31 +00001203 response = read_passphrase(prompt, echo ? RP_ECHO : 0);
Damien Miller874d77b2000-10-14 16:23:11 +11001204
Ben Lindstrom5699c5f2001-03-05 06:17:49 +00001205 packet_put_cstring(response);
Damien Miller874d77b2000-10-14 16:23:11 +11001206 memset(response, 0, strlen(response));
1207 xfree(response);
1208 xfree(prompt);
1209 }
Damien Miller48b03fc2002-01-22 23:11:40 +11001210 packet_check_eom(); /* done with parsing incoming message. */
Damien Miller874d77b2000-10-14 16:23:11 +11001211
Damien Miller9f643902001-11-12 11:02:52 +11001212 packet_add_padding(64);
Damien Miller874d77b2000-10-14 16:23:11 +11001213 packet_send();
Damien Miller874d77b2000-10-14 16:23:11 +11001214}
Damien Miller62cee002000-09-23 17:15:56 +11001215
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001216static int
Ben Lindstrom5c385522002-06-23 21:23:20 +00001217ssh_keysign(Key *key, u_char **sigp, u_int *lenp,
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001218 u_char *data, u_int datalen)
1219{
1220 Buffer b;
Ben Lindstrom5206b952002-06-06 19:59:29 +00001221 struct stat st;
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001222 pid_t pid;
Ben Lindstromcec2ea82002-06-06 20:51:04 +00001223 int to[2], from[2], status, version = 2;
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001224
Ben Lindstrom1d568f92002-12-23 02:44:36 +00001225 debug2("ssh_keysign called");
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001226
Ben Lindstrom5206b952002-06-06 19:59:29 +00001227 if (stat(_PATH_SSH_KEY_SIGN, &st) < 0) {
1228 error("ssh_keysign: no installed: %s", strerror(errno));
1229 return -1;
1230 }
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001231 if (fflush(stdout) != 0)
1232 error("ssh_keysign: fflush: %s", strerror(errno));
1233 if (pipe(to) < 0) {
1234 error("ssh_keysign: pipe: %s", strerror(errno));
1235 return -1;
1236 }
1237 if (pipe(from) < 0) {
1238 error("ssh_keysign: pipe: %s", strerror(errno));
1239 return -1;
1240 }
1241 if ((pid = fork()) < 0) {
1242 error("ssh_keysign: fork: %s", strerror(errno));
1243 return -1;
1244 }
1245 if (pid == 0) {
1246 seteuid(getuid());
1247 setuid(getuid());
1248 close(from[0]);
1249 if (dup2(from[1], STDOUT_FILENO) < 0)
1250 fatal("ssh_keysign: dup2: %s", strerror(errno));
1251 close(to[1]);
1252 if (dup2(to[0], STDIN_FILENO) < 0)
1253 fatal("ssh_keysign: dup2: %s", strerror(errno));
Ben Lindstromcec2ea82002-06-06 20:51:04 +00001254 close(from[1]);
1255 close(to[0]);
Ben Lindstrom4887da22002-06-06 20:05:57 +00001256 execl(_PATH_SSH_KEY_SIGN, _PATH_SSH_KEY_SIGN, (char *) 0);
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001257 fatal("ssh_keysign: exec(%s): %s", _PATH_SSH_KEY_SIGN,
1258 strerror(errno));
1259 }
1260 close(from[1]);
1261 close(to[0]);
1262
1263 buffer_init(&b);
Ben Lindstromcec2ea82002-06-06 20:51:04 +00001264 buffer_put_int(&b, packet_get_connection_in()); /* send # of socket */
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001265 buffer_put_string(&b, data, datalen);
Damien Miller51bf11f2003-11-17 21:20:47 +11001266 if (ssh_msg_send(to[1], version, &b) == -1)
1267 fatal("ssh_keysign: couldn't send request");
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001268
Damien Miller901119b2002-10-04 11:10:04 +10001269 if (ssh_msg_recv(from[0], &b) < 0) {
Ben Lindstrom5206b952002-06-06 19:59:29 +00001270 error("ssh_keysign: no reply");
Damien Millerfb1310e2004-01-21 11:02:50 +11001271 buffer_free(&b);
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001272 return -1;
1273 }
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001274 close(from[0]);
1275 close(to[1]);
1276
Ben Lindstromcec2ea82002-06-06 20:51:04 +00001277 while (waitpid(pid, &status, 0) < 0)
1278 if (errno != EINTR)
1279 break;
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001280
Ben Lindstrom5206b952002-06-06 19:59:29 +00001281 if (buffer_get_char(&b) != version) {
1282 error("ssh_keysign: bad version");
Damien Millerfb1310e2004-01-21 11:02:50 +11001283 buffer_free(&b);
Ben Lindstrom5206b952002-06-06 19:59:29 +00001284 return -1;
1285 }
1286 *sigp = buffer_get_string(&b, lenp);
Damien Millerfb1310e2004-01-21 11:02:50 +11001287 buffer_free(&b);
Ben Lindstrom5206b952002-06-06 19:59:29 +00001288
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001289 return 0;
1290}
1291
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001292int
1293userauth_hostbased(Authctxt *authctxt)
1294{
1295 Key *private = NULL;
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001296 Sensitive *sensitive = authctxt->sensitive;
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001297 Buffer b;
1298 u_char *signature, *blob;
1299 char *chost, *pkalg, *p;
Ben Lindstrom671388f2001-04-19 20:40:45 +00001300 const char *service;
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001301 u_int blen, slen;
Ben Lindstrom2bffd6f2001-04-19 20:35:40 +00001302 int ok, i, len, found = 0;
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001303
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001304 /* check for a useful key */
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001305 for (i = 0; i < sensitive->nkeys; i++) {
1306 private = sensitive->keys[i];
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001307 if (private && private->type != KEY_RSA1) {
1308 found = 1;
1309 /* we take and free the key */
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001310 sensitive->keys[i] = NULL;
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001311 break;
1312 }
1313 }
1314 if (!found) {
Ben Lindstrom1d568f92002-12-23 02:44:36 +00001315 debug("No more client hostkeys for hostbased authentication.");
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001316 return 0;
1317 }
1318 if (key_to_blob(private, &blob, &blen) == 0) {
1319 key_free(private);
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001320 return 0;
1321 }
Damien Miller91c18472001-11-12 11:02:03 +11001322 /* figure out a name for the client host */
1323 p = get_local_name(packet_get_connection_in());
1324 if (p == NULL) {
1325 error("userauth_hostbased: cannot get local ipaddr/name");
1326 key_free(private);
1327 return 0;
1328 }
1329 len = strlen(p) + 2;
1330 chost = xmalloc(len);
1331 strlcpy(chost, p, len);
1332 strlcat(chost, ".", len);
1333 debug2("userauth_hostbased: chost %s", chost);
Damien Miller00111382003-03-10 11:21:17 +11001334 xfree(p);
Damien Miller91c18472001-11-12 11:02:03 +11001335
Ben Lindstrom671388f2001-04-19 20:40:45 +00001336 service = datafellows & SSH_BUG_HBSERVICE ? "ssh-userauth" :
1337 authctxt->service;
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001338 pkalg = xstrdup(key_ssh_name(private));
1339 buffer_init(&b);
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001340 /* construct data */
Ben Lindstrom671388f2001-04-19 20:40:45 +00001341 buffer_put_string(&b, session_id2, session_id2_len);
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001342 buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
1343 buffer_put_cstring(&b, authctxt->server_user);
Ben Lindstrom671388f2001-04-19 20:40:45 +00001344 buffer_put_cstring(&b, service);
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001345 buffer_put_cstring(&b, authctxt->method->name);
1346 buffer_put_cstring(&b, pkalg);
1347 buffer_put_string(&b, blob, blen);
1348 buffer_put_cstring(&b, chost);
1349 buffer_put_cstring(&b, authctxt->local_user);
1350#ifdef DEBUG_PK
1351 buffer_dump(&b);
1352#endif
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001353 if (sensitive->external_keysign)
1354 ok = ssh_keysign(private, &signature, &slen,
1355 buffer_ptr(&b), buffer_len(&b));
1356 else
1357 ok = key_sign(private, &signature, &slen,
1358 buffer_ptr(&b), buffer_len(&b));
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001359 key_free(private);
1360 buffer_free(&b);
1361 if (ok != 0) {
1362 error("key_sign failed");
1363 xfree(chost);
1364 xfree(pkalg);
1365 return 0;
1366 }
1367 packet_start(SSH2_MSG_USERAUTH_REQUEST);
1368 packet_put_cstring(authctxt->server_user);
1369 packet_put_cstring(authctxt->service);
1370 packet_put_cstring(authctxt->method->name);
1371 packet_put_cstring(pkalg);
1372 packet_put_string(blob, blen);
1373 packet_put_cstring(chost);
1374 packet_put_cstring(authctxt->local_user);
1375 packet_put_string(signature, slen);
1376 memset(signature, 's', slen);
1377 xfree(signature);
1378 xfree(chost);
1379 xfree(pkalg);
1380
1381 packet_send();
1382 return 1;
1383}
1384
Damien Miller62cee002000-09-23 17:15:56 +11001385/* find auth method */
1386
Damien Miller62cee002000-09-23 17:15:56 +11001387/*
1388 * given auth method name, if configurable options permit this method fill
1389 * in auth_ident field and return true, otherwise return false.
1390 */
Ben Lindstrombba81212001-06-25 05:01:22 +00001391static int
Damien Miller62cee002000-09-23 17:15:56 +11001392authmethod_is_enabled(Authmethod *method)
1393{
1394 if (method == NULL)
1395 return 0;
1396 /* return false if options indicate this method is disabled */
1397 if (method->enabled == NULL || *method->enabled == 0)
1398 return 0;
1399 /* return false if batch mode is enabled but method needs interactive mode */
1400 if (method->batch_flag != NULL && *method->batch_flag != 0)
1401 return 0;
1402 return 1;
1403}
1404
Ben Lindstrombba81212001-06-25 05:01:22 +00001405static Authmethod *
Damien Miller62cee002000-09-23 17:15:56 +11001406authmethod_lookup(const char *name)
1407{
1408 Authmethod *method = NULL;
1409 if (name != NULL)
1410 for (method = authmethods; method->name != NULL; method++)
1411 if (strcmp(name, method->name) == 0)
1412 return method;
1413 debug2("Unrecognized authentication method name: %s", name ? name : "NULL");
1414 return NULL;
1415}
1416
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001417/* XXX internal state */
1418static Authmethod *current = NULL;
1419static char *supported = NULL;
1420static char *preferred = NULL;
Ben Lindstrom5c385522002-06-23 21:23:20 +00001421
Damien Miller62cee002000-09-23 17:15:56 +11001422/*
1423 * Given the authentication method list sent by the server, return the
1424 * next method we should try. If the server initially sends a nil list,
Ben Lindstroma3700052001-04-05 23:26:32 +00001425 * use a built-in default list.
Kevin Stevesef4eea92001-02-05 12:42:17 +00001426 */
Ben Lindstrombba81212001-06-25 05:01:22 +00001427static Authmethod *
Damien Miller62cee002000-09-23 17:15:56 +11001428authmethod_get(char *authlist)
1429{
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001430 char *name = NULL;
Ben Lindstromc58ab022002-02-26 18:15:09 +00001431 u_int next;
Kevin Stevesef4eea92001-02-05 12:42:17 +00001432
Damien Miller62cee002000-09-23 17:15:56 +11001433 /* Use a suitable default if we're passed a nil list. */
1434 if (authlist == NULL || strlen(authlist) == 0)
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001435 authlist = options.preferred_authentications;
Damien Miller62cee002000-09-23 17:15:56 +11001436
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001437 if (supported == NULL || strcmp(authlist, supported) != 0) {
1438 debug3("start over, passed a different list %s", authlist);
1439 if (supported != NULL)
1440 xfree(supported);
1441 supported = xstrdup(authlist);
1442 preferred = options.preferred_authentications;
1443 debug3("preferred %s", preferred);
1444 current = NULL;
1445 } else if (current != NULL && authmethod_is_enabled(current))
1446 return current;
Damien Millereba71ba2000-04-29 23:57:08 +10001447
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001448 for (;;) {
1449 if ((name = match_list(preferred, supported, &next)) == NULL) {
Ben Lindstrom1d568f92002-12-23 02:44:36 +00001450 debug("No more authentication methods to try.");
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001451 current = NULL;
1452 return NULL;
Damien Miller874d77b2000-10-14 16:23:11 +11001453 }
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001454 preferred += next;
1455 debug3("authmethod_lookup %s", name);
1456 debug3("remaining preferred: %s", preferred);
1457 if ((current = authmethod_lookup(name)) != NULL &&
1458 authmethod_is_enabled(current)) {
1459 debug3("authmethod_is_enabled %s", name);
Ben Lindstrom1d568f92002-12-23 02:44:36 +00001460 debug("Next authentication method: %s", name);
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001461 return current;
1462 }
Damien Millereba71ba2000-04-29 23:57:08 +10001463 }
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001464}
Damien Miller62cee002000-09-23 17:15:56 +11001465
Ben Lindstrom79073822001-07-04 03:42:30 +00001466static char *
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001467authmethods_get(void)
1468{
1469 Authmethod *method = NULL;
Damien Miller0e3b8722002-01-22 23:26:38 +11001470 Buffer b;
1471 char *list;
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001472
Damien Miller0e3b8722002-01-22 23:26:38 +11001473 buffer_init(&b);
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001474 for (method = authmethods; method->name != NULL; method++) {
1475 if (authmethod_is_enabled(method)) {
Damien Miller0e3b8722002-01-22 23:26:38 +11001476 if (buffer_len(&b) > 0)
1477 buffer_append(&b, ",", 1);
1478 buffer_append(&b, method->name, strlen(method->name));
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001479 }
Damien Miller62cee002000-09-23 17:15:56 +11001480 }
Damien Miller0e3b8722002-01-22 23:26:38 +11001481 buffer_append(&b, "\0", 1);
1482 list = xstrdup(buffer_ptr(&b));
1483 buffer_free(&b);
1484 return list;
Damien Millereba71ba2000-04-29 23:57:08 +10001485}