blob: 44764289535e9d93bcd58f2f137a01a9953f9192 [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 Miller0b51a522004-04-20 20:07:19 +100026RCSID("$OpenBSD: sshconnect2.c,v 1.136 2004/04/08 16:08:21 henning 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
Damien Miller0425d402003-11-17 22:18:21 +1100225 {"gssapi-with-mic",
Darren Tucker0efd1552003-08-26 11:49:55 +1000226 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;
Darren Tucker79644822003-10-08 17:37:58 +1000361
Ben Lindstromd26dcf32001-01-06 15:18:16 +0000362 debug3("input_userauth_banner");
363 msg = packet_get_string(NULL);
364 lang = packet_get_string(NULL);
Darren Tucker046dff22003-10-08 17:32:02 +1000365 if (options.log_level > SYSLOG_LEVEL_QUIET)
366 fprintf(stderr, "%s", msg);
Ben Lindstromd26dcf32001-01-06 15:18:16 +0000367 xfree(msg);
368 xfree(lang);
Damien Miller62cee002000-09-23 17:15:56 +1100369}
Ben Lindstrom5c385522002-06-23 21:23:20 +0000370
Damien Miller62cee002000-09-23 17:15:56 +1100371void
Damien Miller630d6f42002-01-22 23:17:30 +1100372input_userauth_success(int type, u_int32_t seq, void *ctxt)
Damien Miller62cee002000-09-23 17:15:56 +1100373{
374 Authctxt *authctxt = ctxt;
375 if (authctxt == NULL)
376 fatal("input_userauth_success: no authentication context");
Darren Tucker79644822003-10-08 17:37:58 +1000377 if (authctxt->authlist) {
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000378 xfree(authctxt->authlist);
Darren Tucker79644822003-10-08 17:37:58 +1000379 authctxt->authlist = NULL;
380 }
381 if (authctxt->methoddata) {
Darren Tucker0efd1552003-08-26 11:49:55 +1000382 xfree(authctxt->methoddata);
Darren Tucker79644822003-10-08 17:37:58 +1000383 authctxt->methoddata = NULL;
384 }
Damien Miller62cee002000-09-23 17:15:56 +1100385 authctxt->success = 1; /* break out */
386}
Ben Lindstrom5c385522002-06-23 21:23:20 +0000387
Damien Miller62cee002000-09-23 17:15:56 +1100388void
Damien Miller630d6f42002-01-22 23:17:30 +1100389input_userauth_failure(int type, u_int32_t seq, void *ctxt)
Damien Miller62cee002000-09-23 17:15:56 +1100390{
Damien Miller62cee002000-09-23 17:15:56 +1100391 Authctxt *authctxt = ctxt;
392 char *authlist = NULL;
393 int partial;
Damien Miller62cee002000-09-23 17:15:56 +1100394
395 if (authctxt == NULL)
396 fatal("input_userauth_failure: no authentication context");
397
Damien Miller874d77b2000-10-14 16:23:11 +1100398 authlist = packet_get_string(NULL);
Damien Miller62cee002000-09-23 17:15:56 +1100399 partial = packet_get_char();
Damien Miller48b03fc2002-01-22 23:11:40 +1100400 packet_check_eom();
Damien Miller62cee002000-09-23 17:15:56 +1100401
402 if (partial != 0)
Damien Miller996acd22003-04-09 20:59:48 +1000403 logit("Authenticated with partial success.");
Ben Lindstrom1d568f92002-12-23 02:44:36 +0000404 debug("Authentications that can continue: %s", authlist);
Damien Miller62cee002000-09-23 17:15:56 +1100405
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000406 userauth(authctxt, authlist);
407}
408void
Damien Miller630d6f42002-01-22 23:17:30 +1100409input_userauth_pk_ok(int type, u_int32_t seq, void *ctxt)
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000410{
411 Authctxt *authctxt = ctxt;
412 Key *key = NULL;
Damien Miller280ecfb2003-05-14 13:46:00 +1000413 Identity *id = NULL;
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000414 Buffer b;
Ben Lindstrom90fd8142002-02-26 18:09:42 +0000415 int pktype, sent = 0;
416 u_int alen, blen;
417 char *pkalg, *fp;
418 u_char *pkblob;
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000419
420 if (authctxt == NULL)
421 fatal("input_userauth_pk_ok: no authentication context");
422 if (datafellows & SSH_BUG_PKOK) {
423 /* this is similar to SSH_BUG_PKAUTH */
424 debug2("input_userauth_pk_ok: SSH_BUG_PKOK");
425 pkblob = packet_get_string(&blen);
426 buffer_init(&b);
427 buffer_append(&b, pkblob, blen);
428 pkalg = buffer_get_string(&b, &alen);
429 buffer_free(&b);
430 } else {
431 pkalg = packet_get_string(&alen);
432 pkblob = packet_get_string(&blen);
Kevin Stevesef4eea92001-02-05 12:42:17 +0000433 }
Damien Miller48b03fc2002-01-22 23:11:40 +1100434 packet_check_eom();
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000435
Damien Miller280ecfb2003-05-14 13:46:00 +1000436 debug("Server accepts key: pkalg %s blen %u", pkalg, blen);
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000437
Damien Miller280ecfb2003-05-14 13:46:00 +1000438 if ((pktype = key_type_from_name(pkalg)) == KEY_UNSPEC) {
439 debug("unknown pkalg %s", pkalg);
440 goto done;
441 }
442 if ((key = key_from_blob(pkblob, blen)) == NULL) {
443 debug("no key from blob. pkalg %s", pkalg);
444 goto done;
445 }
446 if (key->type != pktype) {
447 error("input_userauth_pk_ok: type mismatch "
448 "for decoded key (received %d, expected %d)",
449 key->type, pktype);
450 goto done;
451 }
452 fp = key_fingerprint(key, SSH_FP_MD5, SSH_FP_HEX);
453 debug2("input_userauth_pk_ok: fp %s", fp);
454 xfree(fp);
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000455
Darren Tuckerd05b6012003-10-15 15:55:59 +1000456 /*
457 * search keys in the reverse order, because last candidate has been
458 * moved to the end of the queue. this also avoids confusion by
459 * duplicate keys
460 */
Damien Miller0b51a522004-04-20 20:07:19 +1000461 TAILQ_FOREACH_REVERSE(id, &authctxt->keys, idlist, next) {
Damien Miller280ecfb2003-05-14 13:46:00 +1000462 if (key_equal(key, id->key)) {
463 sent = sign_and_send_pubkey(authctxt, id);
464 break;
465 }
466 }
467done:
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000468 if (key != NULL)
469 key_free(key);
470 xfree(pkalg);
471 xfree(pkblob);
472
Ben Lindstroma962c2f2002-07-04 00:14:17 +0000473 /* try another method if we did not send a packet */
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000474 if (sent == 0)
475 userauth(authctxt, NULL);
Damien Miller62cee002000-09-23 17:15:56 +1100476}
477
Darren Tucker0efd1552003-08-26 11:49:55 +1000478#ifdef GSSAPI
Damien Millera8e06ce2003-11-21 23:48:55 +1100479int
Darren Tucker0efd1552003-08-26 11:49:55 +1000480userauth_gssapi(Authctxt *authctxt)
481{
482 Gssctxt *gssctxt = NULL;
Darren Tucker56afe142003-11-03 20:06:14 +1100483 static gss_OID_set gss_supported = NULL;
Darren Tucker0efd1552003-08-26 11:49:55 +1000484 static int mech = 0;
485 OM_uint32 min;
486 int ok = 0;
487
488 /* Try one GSSAPI method at a time, rather than sending them all at
489 * once. */
490
Darren Tucker56afe142003-11-03 20:06:14 +1100491 if (gss_supported == NULL)
492 gss_indicate_mechs(&min, &gss_supported);
Darren Tucker0efd1552003-08-26 11:49:55 +1000493
494 /* Check to see if the mechanism is usable before we offer it */
Darren Tucker56afe142003-11-03 20:06:14 +1100495 while (mech < gss_supported->count && !ok) {
Darren Tucker0efd1552003-08-26 11:49:55 +1000496 if (gssctxt)
497 ssh_gssapi_delete_ctx(&gssctxt);
498 ssh_gssapi_build_ctx(&gssctxt);
Darren Tucker56afe142003-11-03 20:06:14 +1100499 ssh_gssapi_set_oid(gssctxt, &gss_supported->elements[mech]);
Darren Tucker0efd1552003-08-26 11:49:55 +1000500
501 /* My DER encoding requires length<128 */
Darren Tucker56afe142003-11-03 20:06:14 +1100502 if (gss_supported->elements[mech].length < 128 &&
Darren Tucker0efd1552003-08-26 11:49:55 +1000503 !GSS_ERROR(ssh_gssapi_import_name(gssctxt,
504 authctxt->host))) {
505 ok = 1; /* Mechanism works */
506 } else {
507 mech++;
508 }
509 }
510
511 if (!ok) return 0;
512
513 authctxt->methoddata=(void *)gssctxt;
514
515 packet_start(SSH2_MSG_USERAUTH_REQUEST);
516 packet_put_cstring(authctxt->server_user);
517 packet_put_cstring(authctxt->service);
518 packet_put_cstring(authctxt->method->name);
519
520 packet_put_int(1);
521
Darren Tucker655a5e02003-11-03 20:09:03 +1100522 packet_put_int((gss_supported->elements[mech].length) + 2);
523 packet_put_char(SSH_GSS_OIDTYPE);
524 packet_put_char(gss_supported->elements[mech].length);
525 packet_put_raw(gss_supported->elements[mech].elements,
526 gss_supported->elements[mech].length);
Darren Tucker0efd1552003-08-26 11:49:55 +1000527
528 packet_send();
529
530 dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_RESPONSE, &input_gssapi_response);
531 dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, &input_gssapi_token);
532 dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERROR, &input_gssapi_error);
533 dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK, &input_gssapi_errtok);
534
535 mech++; /* Move along to next candidate */
536
537 return 1;
538}
539
Damien Miller91c6aa42003-11-17 21:20:18 +1100540static OM_uint32
541process_gssapi_token(void *ctxt, gss_buffer_t recv_tok)
542{
543 Authctxt *authctxt = ctxt;
544 Gssctxt *gssctxt = authctxt->methoddata;
545 gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
Damien Miller0425d402003-11-17 22:18:21 +1100546 gss_buffer_desc gssbuf, mic;
547 OM_uint32 status, ms, flags;
548 Buffer b;
Damien Miller787b2ec2003-11-21 23:56:47 +1100549
Damien Miller91c6aa42003-11-17 21:20:18 +1100550 status = ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
Damien Miller0425d402003-11-17 22:18:21 +1100551 recv_tok, &send_tok, &flags);
Damien Miller91c6aa42003-11-17 21:20:18 +1100552
553 if (send_tok.length > 0) {
554 if (GSS_ERROR(status))
555 packet_start(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK);
556 else
557 packet_start(SSH2_MSG_USERAUTH_GSSAPI_TOKEN);
Damien Miller787b2ec2003-11-21 23:56:47 +1100558
Damien Miller91c6aa42003-11-17 21:20:18 +1100559 packet_put_string(send_tok.value, send_tok.length);
560 packet_send();
561 gss_release_buffer(&ms, &send_tok);
562 }
Damien Miller787b2ec2003-11-21 23:56:47 +1100563
Damien Miller91c6aa42003-11-17 21:20:18 +1100564 if (status == GSS_S_COMPLETE) {
Damien Miller0425d402003-11-17 22:18:21 +1100565 /* send either complete or MIC, depending on mechanism */
566 if (!(flags & GSS_C_INTEG_FLAG)) {
567 packet_start(SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE);
568 packet_send();
569 } else {
570 ssh_gssapi_buildmic(&b, authctxt->server_user,
571 authctxt->service, "gssapi-with-mic");
572
573 gssbuf.value = buffer_ptr(&b);
574 gssbuf.length = buffer_len(&b);
Damien Miller787b2ec2003-11-21 23:56:47 +1100575
Damien Miller0425d402003-11-17 22:18:21 +1100576 status = ssh_gssapi_sign(gssctxt, &gssbuf, &mic);
Damien Miller787b2ec2003-11-21 23:56:47 +1100577
Damien Miller0425d402003-11-17 22:18:21 +1100578 if (!GSS_ERROR(status)) {
579 packet_start(SSH2_MSG_USERAUTH_GSSAPI_MIC);
580 packet_put_string(mic.value, mic.length);
Damien Miller787b2ec2003-11-21 23:56:47 +1100581
Damien Miller0425d402003-11-17 22:18:21 +1100582 packet_send();
583 }
Damien Miller787b2ec2003-11-21 23:56:47 +1100584
Damien Miller0425d402003-11-17 22:18:21 +1100585 buffer_free(&b);
586 gss_release_buffer(&ms, &mic);
Damien Miller787b2ec2003-11-21 23:56:47 +1100587 }
Damien Miller91c6aa42003-11-17 21:20:18 +1100588 }
Damien Miller787b2ec2003-11-21 23:56:47 +1100589
Damien Miller91c6aa42003-11-17 21:20:18 +1100590 return status;
591}
592
Darren Tucker0efd1552003-08-26 11:49:55 +1000593void
594input_gssapi_response(int type, u_int32_t plen, void *ctxt)
595{
596 Authctxt *authctxt = ctxt;
597 Gssctxt *gssctxt;
Darren Tucker0efd1552003-08-26 11:49:55 +1000598 int oidlen;
599 char *oidv;
Darren Tucker0efd1552003-08-26 11:49:55 +1000600
601 if (authctxt == NULL)
602 fatal("input_gssapi_response: no authentication context");
603 gssctxt = authctxt->methoddata;
604
605 /* Setup our OID */
606 oidv = packet_get_string(&oidlen);
607
Darren Tucker655a5e02003-11-03 20:09:03 +1100608 if (oidlen <= 2 ||
609 oidv[0] != SSH_GSS_OIDTYPE ||
610 oidv[1] != oidlen - 2) {
Damien Miller91c6aa42003-11-17 21:20:18 +1100611 xfree(oidv);
Darren Tucker655a5e02003-11-03 20:09:03 +1100612 debug("Badly encoded mechanism OID received");
613 userauth(authctxt, NULL);
Darren Tucker655a5e02003-11-03 20:09:03 +1100614 return;
Darren Tucker0efd1552003-08-26 11:49:55 +1000615 }
616
Darren Tucker655a5e02003-11-03 20:09:03 +1100617 if (!ssh_gssapi_check_oid(gssctxt, oidv + 2, oidlen - 2))
618 fatal("Server returned different OID than expected");
619
Darren Tucker0efd1552003-08-26 11:49:55 +1000620 packet_check_eom();
621
622 xfree(oidv);
623
Damien Miller91c6aa42003-11-17 21:20:18 +1100624 if (GSS_ERROR(process_gssapi_token(ctxt, GSS_C_NO_BUFFER))) {
Darren Tucker0efd1552003-08-26 11:49:55 +1000625 /* Start again with next method on list */
626 debug("Trying to start again");
627 userauth(authctxt, NULL);
628 return;
629 }
Darren Tucker0efd1552003-08-26 11:49:55 +1000630}
631
632void
633input_gssapi_token(int type, u_int32_t plen, void *ctxt)
634{
635 Authctxt *authctxt = ctxt;
Darren Tucker0efd1552003-08-26 11:49:55 +1000636 gss_buffer_desc recv_tok;
Damien Miller91c6aa42003-11-17 21:20:18 +1100637 OM_uint32 status;
Darren Tucker0efd1552003-08-26 11:49:55 +1000638 u_int slen;
639
640 if (authctxt == NULL)
641 fatal("input_gssapi_response: no authentication context");
Darren Tucker0efd1552003-08-26 11:49:55 +1000642
643 recv_tok.value = packet_get_string(&slen);
644 recv_tok.length = slen; /* safe typecast */
645
646 packet_check_eom();
647
Damien Miller91c6aa42003-11-17 21:20:18 +1100648 status = process_gssapi_token(ctxt, &recv_tok);
Darren Tucker0efd1552003-08-26 11:49:55 +1000649
650 xfree(recv_tok.value);
651
652 if (GSS_ERROR(status)) {
Darren Tucker0efd1552003-08-26 11:49:55 +1000653 /* Start again with the next method in the list */
654 userauth(authctxt, NULL);
655 return;
656 }
Darren Tucker0efd1552003-08-26 11:49:55 +1000657}
658
659void
660input_gssapi_errtok(int type, u_int32_t plen, void *ctxt)
661{
662 Authctxt *authctxt = ctxt;
663 Gssctxt *gssctxt;
664 gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
665 gss_buffer_desc recv_tok;
666 OM_uint32 status, ms;
Darren Tucker600ad8d2003-08-26 12:10:48 +1000667 u_int len;
Darren Tucker0efd1552003-08-26 11:49:55 +1000668
669 if (authctxt == NULL)
670 fatal("input_gssapi_response: no authentication context");
671 gssctxt = authctxt->methoddata;
672
Darren Tucker600ad8d2003-08-26 12:10:48 +1000673 recv_tok.value = packet_get_string(&len);
674 recv_tok.length = len;
Darren Tucker0efd1552003-08-26 11:49:55 +1000675
676 packet_check_eom();
677
678 /* Stick it into GSSAPI and see what it says */
679 status = ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
680 &recv_tok, &send_tok, NULL);
681
682 xfree(recv_tok.value);
683 gss_release_buffer(&ms, &send_tok);
684
685 /* Server will be returning a failed packet after this one */
686}
687
688void
689input_gssapi_error(int type, u_int32_t plen, void *ctxt)
690{
691 OM_uint32 maj, min;
692 char *msg;
693 char *lang;
694
695 maj=packet_get_int();
696 min=packet_get_int();
697 msg=packet_get_string(NULL);
698 lang=packet_get_string(NULL);
699
700 packet_check_eom();
701
702 debug("Server GSSAPI Error:\n%s\n", msg);
703 xfree(msg);
704 xfree(lang);
705}
706#endif /* GSSAPI */
707
Damien Millereba71ba2000-04-29 23:57:08 +1000708int
Damien Miller874d77b2000-10-14 16:23:11 +1100709userauth_none(Authctxt *authctxt)
710{
711 /* initial userauth request */
712 packet_start(SSH2_MSG_USERAUTH_REQUEST);
713 packet_put_cstring(authctxt->server_user);
714 packet_put_cstring(authctxt->service);
715 packet_put_cstring(authctxt->method->name);
716 packet_send();
Damien Miller874d77b2000-10-14 16:23:11 +1100717 return 1;
718}
719
720int
Damien Miller62cee002000-09-23 17:15:56 +1100721userauth_passwd(Authctxt *authctxt)
Damien Millereba71ba2000-04-29 23:57:08 +1000722{
Damien Millere247cc42000-05-07 12:03:14 +1000723 static int attempt = 0;
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000724 char prompt[150];
Damien Millereba71ba2000-04-29 23:57:08 +1000725 char *password;
726
Damien Millerd3a18572000-06-07 19:55:44 +1000727 if (attempt++ >= options.number_of_password_prompts)
Damien Millere247cc42000-05-07 12:03:14 +1000728 return 0;
729
Ben Lindstrom1c37c6a2001-12-06 18:00:18 +0000730 if (attempt != 1)
Damien Millerd3a18572000-06-07 19:55:44 +1000731 error("Permission denied, please try again.");
732
Ben Lindstrom03df5bd2001-02-10 22:16:41 +0000733 snprintf(prompt, sizeof(prompt), "%.30s@%.128s's password: ",
Damien Miller62cee002000-09-23 17:15:56 +1100734 authctxt->server_user, authctxt->host);
Damien Millereba71ba2000-04-29 23:57:08 +1000735 password = read_passphrase(prompt, 0);
736 packet_start(SSH2_MSG_USERAUTH_REQUEST);
Damien Miller62cee002000-09-23 17:15:56 +1100737 packet_put_cstring(authctxt->server_user);
738 packet_put_cstring(authctxt->service);
Damien Miller874d77b2000-10-14 16:23:11 +1100739 packet_put_cstring(authctxt->method->name);
Damien Millereba71ba2000-04-29 23:57:08 +1000740 packet_put_char(0);
Ben Lindstrom5699c5f2001-03-05 06:17:49 +0000741 packet_put_cstring(password);
Damien Millereba71ba2000-04-29 23:57:08 +1000742 memset(password, 0, strlen(password));
743 xfree(password);
Damien Miller9f643902001-11-12 11:02:52 +1100744 packet_add_padding(64);
Damien Millereba71ba2000-04-29 23:57:08 +1000745 packet_send();
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000746
Ben Lindstromcb72e4f2002-06-21 00:41:51 +0000747 dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000748 &input_userauth_passwd_changereq);
749
Damien Millereba71ba2000-04-29 23:57:08 +1000750 return 1;
751}
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000752/*
753 * parse PASSWD_CHANGEREQ, prompt user and send SSH2_MSG_USERAUTH_REQUEST
754 */
755void
Tim Ricec8549622002-03-31 12:49:38 -0800756input_userauth_passwd_changereq(int type, u_int32_t seqnr, void *ctxt)
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000757{
758 Authctxt *authctxt = ctxt;
759 char *info, *lang, *password = NULL, *retype = NULL;
760 char prompt[150];
761
762 debug2("input_userauth_passwd_changereq");
763
764 if (authctxt == NULL)
765 fatal("input_userauth_passwd_changereq: "
766 "no authentication context");
767
768 info = packet_get_string(NULL);
769 lang = packet_get_string(NULL);
770 if (strlen(info) > 0)
Damien Miller996acd22003-04-09 20:59:48 +1000771 logit("%s", info);
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000772 xfree(info);
773 xfree(lang);
774 packet_start(SSH2_MSG_USERAUTH_REQUEST);
775 packet_put_cstring(authctxt->server_user);
776 packet_put_cstring(authctxt->service);
777 packet_put_cstring(authctxt->method->name);
778 packet_put_char(1); /* additional info */
Ben Lindstromcb72e4f2002-06-21 00:41:51 +0000779 snprintf(prompt, sizeof(prompt),
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000780 "Enter %.30s@%.128s's old password: ",
781 authctxt->server_user, authctxt->host);
782 password = read_passphrase(prompt, 0);
783 packet_put_cstring(password);
784 memset(password, 0, strlen(password));
785 xfree(password);
786 password = NULL;
787 while (password == NULL) {
Ben Lindstromcb72e4f2002-06-21 00:41:51 +0000788 snprintf(prompt, sizeof(prompt),
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000789 "Enter %.30s@%.128s's new password: ",
790 authctxt->server_user, authctxt->host);
791 password = read_passphrase(prompt, RP_ALLOW_EOF);
792 if (password == NULL) {
793 /* bail out */
794 return;
795 }
Ben Lindstromcb72e4f2002-06-21 00:41:51 +0000796 snprintf(prompt, sizeof(prompt),
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000797 "Retype %.30s@%.128s's new password: ",
798 authctxt->server_user, authctxt->host);
799 retype = read_passphrase(prompt, 0);
800 if (strcmp(password, retype) != 0) {
801 memset(password, 0, strlen(password));
802 xfree(password);
Damien Miller996acd22003-04-09 20:59:48 +1000803 logit("Mismatch; try again, EOF to quit.");
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000804 password = NULL;
805 }
806 memset(retype, 0, strlen(retype));
807 xfree(retype);
808 }
809 packet_put_cstring(password);
810 memset(password, 0, strlen(password));
811 xfree(password);
812 packet_add_padding(64);
813 packet_send();
Ben Lindstromcb72e4f2002-06-21 00:41:51 +0000814
815 dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
Ben Lindstrom38a69e62002-03-27 17:28:46 +0000816 &input_userauth_passwd_changereq);
817}
Damien Millereba71ba2000-04-29 23:57:08 +1000818
Ben Lindstrombba81212001-06-25 05:01:22 +0000819static int
Damien Miller280ecfb2003-05-14 13:46:00 +1000820identity_sign(Identity *id, u_char **sigp, u_int *lenp,
821 u_char *data, u_int datalen)
822{
823 Key *prv;
824 int ret;
825
826 /* the agent supports this key */
827 if (id->ac)
828 return (ssh_agent_sign(id->ac, id->key, sigp, lenp,
829 data, datalen));
830 /*
831 * we have already loaded the private key or
832 * the private key is stored in external hardware
833 */
834 if (id->isprivate || (id->key->flags & KEY_FLAG_EXT))
835 return (key_sign(id->key, sigp, lenp, data, datalen));
836 /* load the private key from the file */
837 if ((prv = load_identity_file(id->filename)) == NULL)
838 return (-1);
839 ret = key_sign(prv, sigp, lenp, data, datalen);
840 key_free(prv);
841 return (ret);
842}
843
844static int
845sign_and_send_pubkey(Authctxt *authctxt, Identity *id)
Damien Millereba71ba2000-04-29 23:57:08 +1000846{
847 Buffer b;
Ben Lindstrom46c16222000-12-22 01:43:59 +0000848 u_char *blob, *signature;
Ben Lindstrom90fd8142002-02-26 18:09:42 +0000849 u_int bloblen, slen;
Darren Tucker502d3842003-06-28 12:38:01 +1000850 u_int skip = 0;
Damien Millerad833b32000-08-23 10:46:23 +1000851 int ret = -1;
Damien Miller874d77b2000-10-14 16:23:11 +1100852 int have_sig = 1;
Damien Millereba71ba2000-04-29 23:57:08 +1000853
Ben Lindstromd121f612000-12-03 17:00:47 +0000854 debug3("sign_and_send_pubkey");
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000855
Damien Miller280ecfb2003-05-14 13:46:00 +1000856 if (key_to_blob(id->key, &blob, &bloblen) == 0) {
Damien Miller0bc1bd82000-11-13 22:57:25 +1100857 /* we cannot handle this key */
Ben Lindstromd121f612000-12-03 17:00:47 +0000858 debug3("sign_and_send_pubkey: cannot handle key");
Damien Miller0bc1bd82000-11-13 22:57:25 +1100859 return 0;
860 }
Damien Millereba71ba2000-04-29 23:57:08 +1000861 /* data to be signed */
862 buffer_init(&b);
Damien Miller50a41ed2000-10-16 12:14:42 +1100863 if (datafellows & SSH_OLD_SESSIONID) {
Damien Miller6536c7d2000-06-22 21:32:31 +1000864 buffer_append(&b, session_id2, session_id2_len);
Kevin Stevesef4eea92001-02-05 12:42:17 +0000865 skip = session_id2_len;
Damien Miller50a41ed2000-10-16 12:14:42 +1100866 } else {
867 buffer_put_string(&b, session_id2, session_id2_len);
868 skip = buffer_len(&b);
Damien Miller6536c7d2000-06-22 21:32:31 +1000869 }
Damien Millereba71ba2000-04-29 23:57:08 +1000870 buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
Damien Miller62cee002000-09-23 17:15:56 +1100871 buffer_put_cstring(&b, authctxt->server_user);
Damien Miller30c3d422000-05-09 11:02:59 +1000872 buffer_put_cstring(&b,
Ben Lindstromd121f612000-12-03 17:00:47 +0000873 datafellows & SSH_BUG_PKSERVICE ?
Damien Miller30c3d422000-05-09 11:02:59 +1000874 "ssh-userauth" :
Damien Miller62cee002000-09-23 17:15:56 +1100875 authctxt->service);
Ben Lindstromd121f612000-12-03 17:00:47 +0000876 if (datafellows & SSH_BUG_PKAUTH) {
877 buffer_put_char(&b, have_sig);
878 } else {
879 buffer_put_cstring(&b, authctxt->method->name);
880 buffer_put_char(&b, have_sig);
Damien Miller280ecfb2003-05-14 13:46:00 +1000881 buffer_put_cstring(&b, key_ssh_name(id->key));
Ben Lindstromd121f612000-12-03 17:00:47 +0000882 }
Damien Millereba71ba2000-04-29 23:57:08 +1000883 buffer_put_string(&b, blob, bloblen);
Damien Millereba71ba2000-04-29 23:57:08 +1000884
885 /* generate signature */
Damien Miller280ecfb2003-05-14 13:46:00 +1000886 ret = identity_sign(id, &signature, &slen,
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000887 buffer_ptr(&b), buffer_len(&b));
Damien Millerad833b32000-08-23 10:46:23 +1000888 if (ret == -1) {
889 xfree(blob);
890 buffer_free(&b);
891 return 0;
892 }
Damien Miller0bc1bd82000-11-13 22:57:25 +1100893#ifdef DEBUG_PK
Damien Millereba71ba2000-04-29 23:57:08 +1000894 buffer_dump(&b);
895#endif
Ben Lindstromd121f612000-12-03 17:00:47 +0000896 if (datafellows & SSH_BUG_PKSERVICE) {
Damien Miller30c3d422000-05-09 11:02:59 +1000897 buffer_clear(&b);
898 buffer_append(&b, session_id2, session_id2_len);
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000899 skip = session_id2_len;
Damien Miller30c3d422000-05-09 11:02:59 +1000900 buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
Damien Miller62cee002000-09-23 17:15:56 +1100901 buffer_put_cstring(&b, authctxt->server_user);
902 buffer_put_cstring(&b, authctxt->service);
Damien Miller874d77b2000-10-14 16:23:11 +1100903 buffer_put_cstring(&b, authctxt->method->name);
904 buffer_put_char(&b, have_sig);
Ben Lindstromd121f612000-12-03 17:00:47 +0000905 if (!(datafellows & SSH_BUG_PKAUTH))
Damien Miller280ecfb2003-05-14 13:46:00 +1000906 buffer_put_cstring(&b, key_ssh_name(id->key));
Damien Miller30c3d422000-05-09 11:02:59 +1000907 buffer_put_string(&b, blob, bloblen);
908 }
909 xfree(blob);
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000910
Damien Millereba71ba2000-04-29 23:57:08 +1000911 /* append signature */
912 buffer_put_string(&b, signature, slen);
913 xfree(signature);
914
915 /* skip session id and packet type */
Damien Miller6536c7d2000-06-22 21:32:31 +1000916 if (buffer_len(&b) < skip + 1)
Damien Miller62cee002000-09-23 17:15:56 +1100917 fatal("userauth_pubkey: internal error");
Damien Miller6536c7d2000-06-22 21:32:31 +1000918 buffer_consume(&b, skip + 1);
Damien Millereba71ba2000-04-29 23:57:08 +1000919
920 /* put remaining data from buffer into packet */
921 packet_start(SSH2_MSG_USERAUTH_REQUEST);
922 packet_put_raw(buffer_ptr(&b), buffer_len(&b));
923 buffer_free(&b);
Damien Millereba71ba2000-04-29 23:57:08 +1000924 packet_send();
Damien Millerad833b32000-08-23 10:46:23 +1000925
926 return 1;
Damien Miller994cf142000-07-21 10:19:44 +1000927}
928
Ben Lindstrombba81212001-06-25 05:01:22 +0000929static int
Damien Miller280ecfb2003-05-14 13:46:00 +1000930send_pubkey_test(Authctxt *authctxt, Identity *id)
Damien Miller994cf142000-07-21 10:19:44 +1000931{
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000932 u_char *blob;
Ben Lindstromc58ab022002-02-26 18:15:09 +0000933 u_int bloblen, have_sig = 0;
Damien Miller994cf142000-07-21 10:19:44 +1000934
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000935 debug3("send_pubkey_test");
936
Damien Miller280ecfb2003-05-14 13:46:00 +1000937 if (key_to_blob(id->key, &blob, &bloblen) == 0) {
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000938 /* we cannot handle this key */
939 debug3("send_pubkey_test: cannot handle key");
Damien Miller994cf142000-07-21 10:19:44 +1000940 return 0;
941 }
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000942 /* register callback for USERAUTH_PK_OK message */
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000943 dispatch_set(SSH2_MSG_USERAUTH_PK_OK, &input_userauth_pk_ok);
Damien Miller994cf142000-07-21 10:19:44 +1000944
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000945 packet_start(SSH2_MSG_USERAUTH_REQUEST);
946 packet_put_cstring(authctxt->server_user);
947 packet_put_cstring(authctxt->service);
948 packet_put_cstring(authctxt->method->name);
949 packet_put_char(have_sig);
950 if (!(datafellows & SSH_BUG_PKAUTH))
Damien Miller280ecfb2003-05-14 13:46:00 +1000951 packet_put_cstring(key_ssh_name(id->key));
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000952 packet_put_string(blob, bloblen);
953 xfree(blob);
954 packet_send();
955 return 1;
956}
957
Ben Lindstrombba81212001-06-25 05:01:22 +0000958static Key *
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000959load_identity_file(char *filename)
960{
961 Key *private;
962 char prompt[300], *passphrase;
Ben Lindstromd0fca422001-03-26 13:44:06 +0000963 int quit, i;
Ben Lindstrom329782e2001-03-10 17:08:59 +0000964 struct stat st;
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000965
Ben Lindstrom329782e2001-03-10 17:08:59 +0000966 if (stat(filename, &st) < 0) {
967 debug3("no such identity: %s", filename);
968 return NULL;
969 }
Ben Lindstromd0fca422001-03-26 13:44:06 +0000970 private = key_load_private_type(KEY_UNSPEC, filename, "", NULL);
971 if (private == NULL) {
972 if (options.batch_mode)
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000973 return NULL;
Damien Miller994cf142000-07-21 10:19:44 +1000974 snprintf(prompt, sizeof prompt,
Damien Miller9f0f5c62001-12-21 14:45:46 +1100975 "Enter passphrase for key '%.100s': ", filename);
Damien Miller62cee002000-09-23 17:15:56 +1100976 for (i = 0; i < options.number_of_password_prompts; i++) {
977 passphrase = read_passphrase(prompt, 0);
978 if (strcmp(passphrase, "") != 0) {
Ben Lindstromd0fca422001-03-26 13:44:06 +0000979 private = key_load_private_type(KEY_UNSPEC, filename,
980 passphrase, NULL);
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000981 quit = 0;
Damien Miller62cee002000-09-23 17:15:56 +1100982 } else {
983 debug2("no passphrase given, try next key");
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000984 quit = 1;
Damien Miller62cee002000-09-23 17:15:56 +1100985 }
986 memset(passphrase, 0, strlen(passphrase));
987 xfree(passphrase);
Ben Lindstromd0fca422001-03-26 13:44:06 +0000988 if (private != NULL || quit)
Damien Miller62cee002000-09-23 17:15:56 +1100989 break;
990 debug2("bad passphrase given, try again...");
991 }
Damien Miller994cf142000-07-21 10:19:44 +1000992 }
Ben Lindstrom266dfdf2001-03-09 00:12:22 +0000993 return private;
994}
995
Damien Miller280ecfb2003-05-14 13:46:00 +1000996/*
997 * try keys in the following order:
998 * 1. agent keys that are found in the config file
999 * 2. other agent keys
1000 * 3. keys that are only listed in the config file
1001 */
1002static void
1003pubkey_prepare(Authctxt *authctxt)
Ben Lindstrom266dfdf2001-03-09 00:12:22 +00001004{
Damien Miller280ecfb2003-05-14 13:46:00 +10001005 Identity *id;
1006 Idlist agent, files, *preferred;
1007 Key *key;
1008 AuthenticationConnection *ac;
Damien Millerad833b32000-08-23 10:46:23 +10001009 char *comment;
Damien Miller280ecfb2003-05-14 13:46:00 +10001010 int i, found;
Damien Millerad833b32000-08-23 10:46:23 +10001011
Damien Miller280ecfb2003-05-14 13:46:00 +10001012 TAILQ_INIT(&agent); /* keys from the agent */
1013 TAILQ_INIT(&files); /* keys from the config file */
1014 preferred = &authctxt->keys;
1015 TAILQ_INIT(preferred); /* preferred order of keys */
1016
1017 /* list of keys stored in the filesystem */
1018 for (i = 0; i < options.num_identity_files; i++) {
1019 key = options.identity_keys[i];
1020 if (key && key->type == KEY_RSA1)
1021 continue;
1022 options.identity_keys[i] = NULL;
1023 id = xmalloc(sizeof(*id));
1024 memset(id, 0, sizeof(*id));
1025 id->key = key;
1026 id->filename = xstrdup(options.identity_files[i]);
1027 TAILQ_INSERT_TAIL(&files, id, next);
Damien Millerad833b32000-08-23 10:46:23 +10001028 }
Damien Miller280ecfb2003-05-14 13:46:00 +10001029 /* list of keys supported by the agent */
1030 if ((ac = ssh_get_authentication_connection())) {
1031 for (key = ssh_get_first_identity(ac, &comment, 2);
1032 key != NULL;
1033 key = ssh_get_next_identity(ac, &comment, 2)) {
1034 found = 0;
1035 TAILQ_FOREACH(id, &files, next) {
Damien Millera8e06ce2003-11-21 23:48:55 +11001036 /* agent keys from the config file are preferred */
Damien Miller280ecfb2003-05-14 13:46:00 +10001037 if (key_equal(key, id->key)) {
1038 key_free(key);
1039 xfree(comment);
1040 TAILQ_REMOVE(&files, id, next);
1041 TAILQ_INSERT_TAIL(preferred, id, next);
1042 id->ac = ac;
1043 found = 1;
1044 break;
1045 }
1046 }
Damien Millerbd394c32004-03-08 23:12:36 +11001047 if (!found && !options.identities_only) {
Damien Miller280ecfb2003-05-14 13:46:00 +10001048 id = xmalloc(sizeof(*id));
1049 memset(id, 0, sizeof(*id));
1050 id->key = key;
1051 id->filename = comment;
1052 id->ac = ac;
1053 TAILQ_INSERT_TAIL(&agent, id, next);
1054 }
1055 }
1056 /* append remaining agent keys */
1057 for (id = TAILQ_FIRST(&agent); id; id = TAILQ_FIRST(&agent)) {
1058 TAILQ_REMOVE(&agent, id, next);
1059 TAILQ_INSERT_TAIL(preferred, id, next);
1060 }
1061 authctxt->agent = ac;
Damien Miller62cee002000-09-23 17:15:56 +11001062 }
Damien Miller280ecfb2003-05-14 13:46:00 +10001063 /* append remaining keys from the config file */
1064 for (id = TAILQ_FIRST(&files); id; id = TAILQ_FIRST(&files)) {
1065 TAILQ_REMOVE(&files, id, next);
1066 TAILQ_INSERT_TAIL(preferred, id, next);
1067 }
1068 TAILQ_FOREACH(id, preferred, next) {
1069 debug2("key: %s (%p)", id->filename, id->key);
1070 }
1071}
1072
1073static void
1074pubkey_cleanup(Authctxt *authctxt)
1075{
1076 Identity *id;
1077
1078 if (authctxt->agent != NULL)
1079 ssh_close_authentication_connection(authctxt->agent);
1080 for (id = TAILQ_FIRST(&authctxt->keys); id;
1081 id = TAILQ_FIRST(&authctxt->keys)) {
1082 TAILQ_REMOVE(&authctxt->keys, id, next);
1083 if (id->key)
1084 key_free(id->key);
1085 if (id->filename)
1086 xfree(id->filename);
1087 xfree(id);
1088 }
Damien Millereba71ba2000-04-29 23:57:08 +10001089}
1090
Damien Miller62cee002000-09-23 17:15:56 +11001091int
1092userauth_pubkey(Authctxt *authctxt)
Damien Millereba71ba2000-04-29 23:57:08 +10001093{
Damien Miller280ecfb2003-05-14 13:46:00 +10001094 Identity *id;
Damien Miller62cee002000-09-23 17:15:56 +11001095 int sent = 0;
Damien Millereba71ba2000-04-29 23:57:08 +10001096
Damien Miller280ecfb2003-05-14 13:46:00 +10001097 while ((id = TAILQ_FIRST(&authctxt->keys))) {
1098 if (id->tried++)
1099 return (0);
Darren Tuckerd05b6012003-10-15 15:55:59 +10001100 /* move key to the end of the queue */
Damien Miller280ecfb2003-05-14 13:46:00 +10001101 TAILQ_REMOVE(&authctxt->keys, id, next);
1102 TAILQ_INSERT_TAIL(&authctxt->keys, id, next);
1103 /*
1104 * send a test message if we have the public key. for
1105 * encrypted keys we cannot do this and have to load the
1106 * private key instead
1107 */
1108 if (id->key && id->key->type != KEY_RSA1) {
1109 debug("Offering public key: %s", id->filename);
1110 sent = send_pubkey_test(authctxt, id);
1111 } else if (id->key == NULL) {
1112 debug("Trying private key: %s", id->filename);
1113 id->key = load_identity_file(id->filename);
1114 if (id->key != NULL) {
1115 id->isprivate = 1;
1116 sent = sign_and_send_pubkey(authctxt, id);
1117 key_free(id->key);
1118 id->key = NULL;
Ben Lindstrom266dfdf2001-03-09 00:12:22 +00001119 }
Ben Lindstrom266dfdf2001-03-09 00:12:22 +00001120 }
Damien Miller280ecfb2003-05-14 13:46:00 +10001121 if (sent)
1122 return (sent);
Damien Miller0bc1bd82000-11-13 22:57:25 +11001123 }
Damien Miller280ecfb2003-05-14 13:46:00 +10001124 return (0);
Damien Miller62cee002000-09-23 17:15:56 +11001125}
Damien Millereba71ba2000-04-29 23:57:08 +10001126
Damien Miller874d77b2000-10-14 16:23:11 +11001127/*
1128 * Send userauth request message specifying keyboard-interactive method.
1129 */
1130int
1131userauth_kbdint(Authctxt *authctxt)
1132{
1133 static int attempt = 0;
1134
1135 if (attempt++ >= options.number_of_password_prompts)
1136 return 0;
Ben Lindstrom7d199962001-09-12 18:29:00 +00001137 /* disable if no SSH2_MSG_USERAUTH_INFO_REQUEST has been seen */
1138 if (attempt > 1 && !authctxt->info_req_seen) {
1139 debug3("userauth_kbdint: disable: no info_req_seen");
1140 dispatch_set(SSH2_MSG_USERAUTH_INFO_REQUEST, NULL);
1141 return 0;
1142 }
Damien Miller874d77b2000-10-14 16:23:11 +11001143
1144 debug2("userauth_kbdint");
1145 packet_start(SSH2_MSG_USERAUTH_REQUEST);
1146 packet_put_cstring(authctxt->server_user);
1147 packet_put_cstring(authctxt->service);
1148 packet_put_cstring(authctxt->method->name);
1149 packet_put_cstring(""); /* lang */
1150 packet_put_cstring(options.kbd_interactive_devices ?
1151 options.kbd_interactive_devices : "");
1152 packet_send();
Damien Miller874d77b2000-10-14 16:23:11 +11001153
1154 dispatch_set(SSH2_MSG_USERAUTH_INFO_REQUEST, &input_userauth_info_req);
1155 return 1;
1156}
1157
1158/*
Ben Lindstrom03df5bd2001-02-10 22:16:41 +00001159 * parse INFO_REQUEST, prompt user and send INFO_RESPONSE
Damien Miller874d77b2000-10-14 16:23:11 +11001160 */
1161void
Damien Miller630d6f42002-01-22 23:17:30 +11001162input_userauth_info_req(int type, u_int32_t seq, void *ctxt)
Damien Miller874d77b2000-10-14 16:23:11 +11001163{
1164 Authctxt *authctxt = ctxt;
Ben Lindstrom03df5bd2001-02-10 22:16:41 +00001165 char *name, *inst, *lang, *prompt, *response;
Ben Lindstrom46c16222000-12-22 01:43:59 +00001166 u_int num_prompts, i;
Damien Miller874d77b2000-10-14 16:23:11 +11001167 int echo = 0;
1168
1169 debug2("input_userauth_info_req");
1170
1171 if (authctxt == NULL)
1172 fatal("input_userauth_info_req: no authentication context");
1173
Ben Lindstrom7d199962001-09-12 18:29:00 +00001174 authctxt->info_req_seen = 1;
1175
Damien Miller874d77b2000-10-14 16:23:11 +11001176 name = packet_get_string(NULL);
1177 inst = packet_get_string(NULL);
1178 lang = packet_get_string(NULL);
Damien Miller874d77b2000-10-14 16:23:11 +11001179 if (strlen(name) > 0)
Damien Miller996acd22003-04-09 20:59:48 +10001180 logit("%s", name);
Damien Miller874d77b2000-10-14 16:23:11 +11001181 if (strlen(inst) > 0)
Damien Miller996acd22003-04-09 20:59:48 +10001182 logit("%s", inst);
Ben Lindstrom03df5bd2001-02-10 22:16:41 +00001183 xfree(name);
Damien Miller874d77b2000-10-14 16:23:11 +11001184 xfree(inst);
Ben Lindstrom03df5bd2001-02-10 22:16:41 +00001185 xfree(lang);
Damien Miller874d77b2000-10-14 16:23:11 +11001186
1187 num_prompts = packet_get_int();
1188 /*
1189 * Begin to build info response packet based on prompts requested.
1190 * We commit to providing the correct number of responses, so if
1191 * further on we run into a problem that prevents this, we have to
1192 * be sure and clean this up and send a correct error response.
1193 */
1194 packet_start(SSH2_MSG_USERAUTH_INFO_RESPONSE);
1195 packet_put_int(num_prompts);
1196
Ben Lindstrom551ea372001-06-05 18:56:16 +00001197 debug2("input_userauth_info_req: num_prompts %d", num_prompts);
Damien Miller874d77b2000-10-14 16:23:11 +11001198 for (i = 0; i < num_prompts; i++) {
1199 prompt = packet_get_string(NULL);
1200 echo = packet_get_char();
1201
Ben Lindstrom949974b2001-06-25 05:20:31 +00001202 response = read_passphrase(prompt, echo ? RP_ECHO : 0);
Damien Miller874d77b2000-10-14 16:23:11 +11001203
Ben Lindstrom5699c5f2001-03-05 06:17:49 +00001204 packet_put_cstring(response);
Damien Miller874d77b2000-10-14 16:23:11 +11001205 memset(response, 0, strlen(response));
1206 xfree(response);
1207 xfree(prompt);
1208 }
Damien Miller48b03fc2002-01-22 23:11:40 +11001209 packet_check_eom(); /* done with parsing incoming message. */
Damien Miller874d77b2000-10-14 16:23:11 +11001210
Damien Miller9f643902001-11-12 11:02:52 +11001211 packet_add_padding(64);
Damien Miller874d77b2000-10-14 16:23:11 +11001212 packet_send();
Damien Miller874d77b2000-10-14 16:23:11 +11001213}
Damien Miller62cee002000-09-23 17:15:56 +11001214
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001215static int
Ben Lindstrom5c385522002-06-23 21:23:20 +00001216ssh_keysign(Key *key, u_char **sigp, u_int *lenp,
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001217 u_char *data, u_int datalen)
1218{
1219 Buffer b;
Ben Lindstrom5206b952002-06-06 19:59:29 +00001220 struct stat st;
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001221 pid_t pid;
Ben Lindstromcec2ea82002-06-06 20:51:04 +00001222 int to[2], from[2], status, version = 2;
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001223
Ben Lindstrom1d568f92002-12-23 02:44:36 +00001224 debug2("ssh_keysign called");
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001225
Ben Lindstrom5206b952002-06-06 19:59:29 +00001226 if (stat(_PATH_SSH_KEY_SIGN, &st) < 0) {
1227 error("ssh_keysign: no installed: %s", strerror(errno));
1228 return -1;
1229 }
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001230 if (fflush(stdout) != 0)
1231 error("ssh_keysign: fflush: %s", strerror(errno));
1232 if (pipe(to) < 0) {
1233 error("ssh_keysign: pipe: %s", strerror(errno));
1234 return -1;
1235 }
1236 if (pipe(from) < 0) {
1237 error("ssh_keysign: pipe: %s", strerror(errno));
1238 return -1;
1239 }
1240 if ((pid = fork()) < 0) {
1241 error("ssh_keysign: fork: %s", strerror(errno));
1242 return -1;
1243 }
1244 if (pid == 0) {
1245 seteuid(getuid());
1246 setuid(getuid());
1247 close(from[0]);
1248 if (dup2(from[1], STDOUT_FILENO) < 0)
1249 fatal("ssh_keysign: dup2: %s", strerror(errno));
1250 close(to[1]);
1251 if (dup2(to[0], STDIN_FILENO) < 0)
1252 fatal("ssh_keysign: dup2: %s", strerror(errno));
Ben Lindstromcec2ea82002-06-06 20:51:04 +00001253 close(from[1]);
1254 close(to[0]);
Ben Lindstrom4887da22002-06-06 20:05:57 +00001255 execl(_PATH_SSH_KEY_SIGN, _PATH_SSH_KEY_SIGN, (char *) 0);
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001256 fatal("ssh_keysign: exec(%s): %s", _PATH_SSH_KEY_SIGN,
1257 strerror(errno));
1258 }
1259 close(from[1]);
1260 close(to[0]);
1261
1262 buffer_init(&b);
Ben Lindstromcec2ea82002-06-06 20:51:04 +00001263 buffer_put_int(&b, packet_get_connection_in()); /* send # of socket */
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001264 buffer_put_string(&b, data, datalen);
Damien Miller51bf11f2003-11-17 21:20:47 +11001265 if (ssh_msg_send(to[1], version, &b) == -1)
1266 fatal("ssh_keysign: couldn't send request");
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001267
Damien Miller901119b2002-10-04 11:10:04 +10001268 if (ssh_msg_recv(from[0], &b) < 0) {
Ben Lindstrom5206b952002-06-06 19:59:29 +00001269 error("ssh_keysign: no reply");
Damien Millerfb1310e2004-01-21 11:02:50 +11001270 buffer_free(&b);
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001271 return -1;
1272 }
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001273 close(from[0]);
1274 close(to[1]);
1275
Ben Lindstromcec2ea82002-06-06 20:51:04 +00001276 while (waitpid(pid, &status, 0) < 0)
1277 if (errno != EINTR)
1278 break;
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001279
Ben Lindstrom5206b952002-06-06 19:59:29 +00001280 if (buffer_get_char(&b) != version) {
1281 error("ssh_keysign: bad version");
Damien Millerfb1310e2004-01-21 11:02:50 +11001282 buffer_free(&b);
Ben Lindstrom5206b952002-06-06 19:59:29 +00001283 return -1;
1284 }
1285 *sigp = buffer_get_string(&b, lenp);
Damien Millerfb1310e2004-01-21 11:02:50 +11001286 buffer_free(&b);
Ben Lindstrom5206b952002-06-06 19:59:29 +00001287
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001288 return 0;
1289}
1290
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001291int
1292userauth_hostbased(Authctxt *authctxt)
1293{
1294 Key *private = NULL;
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001295 Sensitive *sensitive = authctxt->sensitive;
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001296 Buffer b;
1297 u_char *signature, *blob;
1298 char *chost, *pkalg, *p;
Ben Lindstrom671388f2001-04-19 20:40:45 +00001299 const char *service;
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001300 u_int blen, slen;
Ben Lindstrom2bffd6f2001-04-19 20:35:40 +00001301 int ok, i, len, found = 0;
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001302
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001303 /* check for a useful key */
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001304 for (i = 0; i < sensitive->nkeys; i++) {
1305 private = sensitive->keys[i];
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001306 if (private && private->type != KEY_RSA1) {
1307 found = 1;
1308 /* we take and free the key */
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001309 sensitive->keys[i] = NULL;
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001310 break;
1311 }
1312 }
1313 if (!found) {
Ben Lindstrom1d568f92002-12-23 02:44:36 +00001314 debug("No more client hostkeys for hostbased authentication.");
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001315 return 0;
1316 }
1317 if (key_to_blob(private, &blob, &blen) == 0) {
1318 key_free(private);
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001319 return 0;
1320 }
Damien Miller91c18472001-11-12 11:02:03 +11001321 /* figure out a name for the client host */
1322 p = get_local_name(packet_get_connection_in());
1323 if (p == NULL) {
1324 error("userauth_hostbased: cannot get local ipaddr/name");
1325 key_free(private);
1326 return 0;
1327 }
1328 len = strlen(p) + 2;
1329 chost = xmalloc(len);
1330 strlcpy(chost, p, len);
1331 strlcat(chost, ".", len);
1332 debug2("userauth_hostbased: chost %s", chost);
Damien Miller00111382003-03-10 11:21:17 +11001333 xfree(p);
Damien Miller91c18472001-11-12 11:02:03 +11001334
Ben Lindstrom671388f2001-04-19 20:40:45 +00001335 service = datafellows & SSH_BUG_HBSERVICE ? "ssh-userauth" :
1336 authctxt->service;
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001337 pkalg = xstrdup(key_ssh_name(private));
1338 buffer_init(&b);
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001339 /* construct data */
Ben Lindstrom671388f2001-04-19 20:40:45 +00001340 buffer_put_string(&b, session_id2, session_id2_len);
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001341 buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
1342 buffer_put_cstring(&b, authctxt->server_user);
Ben Lindstrom671388f2001-04-19 20:40:45 +00001343 buffer_put_cstring(&b, service);
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001344 buffer_put_cstring(&b, authctxt->method->name);
1345 buffer_put_cstring(&b, pkalg);
1346 buffer_put_string(&b, blob, blen);
1347 buffer_put_cstring(&b, chost);
1348 buffer_put_cstring(&b, authctxt->local_user);
1349#ifdef DEBUG_PK
1350 buffer_dump(&b);
1351#endif
Ben Lindstrom1bad2562002-06-06 19:57:33 +00001352 if (sensitive->external_keysign)
1353 ok = ssh_keysign(private, &signature, &slen,
1354 buffer_ptr(&b), buffer_len(&b));
1355 else
1356 ok = key_sign(private, &signature, &slen,
1357 buffer_ptr(&b), buffer_len(&b));
Ben Lindstrom5eabda32001-04-12 23:34:34 +00001358 key_free(private);
1359 buffer_free(&b);
1360 if (ok != 0) {
1361 error("key_sign failed");
1362 xfree(chost);
1363 xfree(pkalg);
1364 return 0;
1365 }
1366 packet_start(SSH2_MSG_USERAUTH_REQUEST);
1367 packet_put_cstring(authctxt->server_user);
1368 packet_put_cstring(authctxt->service);
1369 packet_put_cstring(authctxt->method->name);
1370 packet_put_cstring(pkalg);
1371 packet_put_string(blob, blen);
1372 packet_put_cstring(chost);
1373 packet_put_cstring(authctxt->local_user);
1374 packet_put_string(signature, slen);
1375 memset(signature, 's', slen);
1376 xfree(signature);
1377 xfree(chost);
1378 xfree(pkalg);
1379
1380 packet_send();
1381 return 1;
1382}
1383
Damien Miller62cee002000-09-23 17:15:56 +11001384/* find auth method */
1385
Damien Miller62cee002000-09-23 17:15:56 +11001386/*
1387 * given auth method name, if configurable options permit this method fill
1388 * in auth_ident field and return true, otherwise return false.
1389 */
Ben Lindstrombba81212001-06-25 05:01:22 +00001390static int
Damien Miller62cee002000-09-23 17:15:56 +11001391authmethod_is_enabled(Authmethod *method)
1392{
1393 if (method == NULL)
1394 return 0;
1395 /* return false if options indicate this method is disabled */
1396 if (method->enabled == NULL || *method->enabled == 0)
1397 return 0;
1398 /* return false if batch mode is enabled but method needs interactive mode */
1399 if (method->batch_flag != NULL && *method->batch_flag != 0)
1400 return 0;
1401 return 1;
1402}
1403
Ben Lindstrombba81212001-06-25 05:01:22 +00001404static Authmethod *
Damien Miller62cee002000-09-23 17:15:56 +11001405authmethod_lookup(const char *name)
1406{
1407 Authmethod *method = NULL;
1408 if (name != NULL)
1409 for (method = authmethods; method->name != NULL; method++)
1410 if (strcmp(name, method->name) == 0)
1411 return method;
1412 debug2("Unrecognized authentication method name: %s", name ? name : "NULL");
1413 return NULL;
1414}
1415
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001416/* XXX internal state */
1417static Authmethod *current = NULL;
1418static char *supported = NULL;
1419static char *preferred = NULL;
Ben Lindstrom5c385522002-06-23 21:23:20 +00001420
Damien Miller62cee002000-09-23 17:15:56 +11001421/*
1422 * Given the authentication method list sent by the server, return the
1423 * next method we should try. If the server initially sends a nil list,
Ben Lindstroma3700052001-04-05 23:26:32 +00001424 * use a built-in default list.
Kevin Stevesef4eea92001-02-05 12:42:17 +00001425 */
Ben Lindstrombba81212001-06-25 05:01:22 +00001426static Authmethod *
Damien Miller62cee002000-09-23 17:15:56 +11001427authmethod_get(char *authlist)
1428{
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001429 char *name = NULL;
Ben Lindstromc58ab022002-02-26 18:15:09 +00001430 u_int next;
Kevin Stevesef4eea92001-02-05 12:42:17 +00001431
Damien Miller62cee002000-09-23 17:15:56 +11001432 /* Use a suitable default if we're passed a nil list. */
1433 if (authlist == NULL || strlen(authlist) == 0)
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001434 authlist = options.preferred_authentications;
Damien Miller62cee002000-09-23 17:15:56 +11001435
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001436 if (supported == NULL || strcmp(authlist, supported) != 0) {
1437 debug3("start over, passed a different list %s", authlist);
1438 if (supported != NULL)
1439 xfree(supported);
1440 supported = xstrdup(authlist);
1441 preferred = options.preferred_authentications;
1442 debug3("preferred %s", preferred);
1443 current = NULL;
1444 } else if (current != NULL && authmethod_is_enabled(current))
1445 return current;
Damien Millereba71ba2000-04-29 23:57:08 +10001446
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001447 for (;;) {
1448 if ((name = match_list(preferred, supported, &next)) == NULL) {
Ben Lindstrom1d568f92002-12-23 02:44:36 +00001449 debug("No more authentication methods to try.");
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001450 current = NULL;
1451 return NULL;
Damien Miller874d77b2000-10-14 16:23:11 +11001452 }
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001453 preferred += next;
1454 debug3("authmethod_lookup %s", name);
1455 debug3("remaining preferred: %s", preferred);
1456 if ((current = authmethod_lookup(name)) != NULL &&
1457 authmethod_is_enabled(current)) {
1458 debug3("authmethod_is_enabled %s", name);
Ben Lindstrom1d568f92002-12-23 02:44:36 +00001459 debug("Next authentication method: %s", name);
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001460 return current;
1461 }
Damien Millereba71ba2000-04-29 23:57:08 +10001462 }
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001463}
Damien Miller62cee002000-09-23 17:15:56 +11001464
Ben Lindstrom79073822001-07-04 03:42:30 +00001465static char *
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001466authmethods_get(void)
1467{
1468 Authmethod *method = NULL;
Damien Miller0e3b8722002-01-22 23:26:38 +11001469 Buffer b;
1470 char *list;
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001471
Damien Miller0e3b8722002-01-22 23:26:38 +11001472 buffer_init(&b);
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001473 for (method = authmethods; method->name != NULL; method++) {
1474 if (authmethod_is_enabled(method)) {
Damien Miller0e3b8722002-01-22 23:26:38 +11001475 if (buffer_len(&b) > 0)
1476 buffer_append(&b, ",", 1);
1477 buffer_append(&b, method->name, strlen(method->name));
Ben Lindstromb9be60a2001-03-11 01:49:19 +00001478 }
Damien Miller62cee002000-09-23 17:15:56 +11001479 }
Damien Miller0e3b8722002-01-22 23:26:38 +11001480 buffer_append(&b, "\0", 1);
1481 list = xstrdup(buffer_ptr(&b));
1482 buffer_free(&b);
1483 return list;
Damien Millereba71ba2000-04-29 23:57:08 +10001484}