Damien Miller | 0b4d48b | 2008-07-05 09:44:53 +1000 | [diff] [blame^] | 1 | /* $OpenBSD: auth2.c,v 1.119 2008/07/04 23:30:16 djm Exp $ */ |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 2 | /* |
| 3 | * Copyright (c) 2000 Markus Friedl. All rights reserved. |
| 4 | * |
| 5 | * Redistribution and use in source and binary forms, with or without |
| 6 | * modification, are permitted provided that the following conditions |
| 7 | * are met: |
| 8 | * 1. Redistributions of source code must retain the above copyright |
| 9 | * notice, this list of conditions and the following disclaimer. |
| 10 | * 2. Redistributions in binary form must reproduce the above copyright |
| 11 | * notice, this list of conditions and the following disclaimer in the |
| 12 | * documentation and/or other materials provided with the distribution. |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 13 | * |
| 14 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
| 15 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| 16 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| 17 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
| 18 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| 19 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| 20 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| 21 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 22 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| 23 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 24 | */ |
Damien Miller | e4340be | 2000-09-16 13:29:08 +1100 | [diff] [blame] | 25 | |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 26 | #include "includes.h" |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 27 | |
Damien Miller | 9f2abc4 | 2006-07-10 20:53:08 +1000 | [diff] [blame] | 28 | #include <sys/types.h> |
Darren Tucker | 4230a5d | 2008-07-02 22:56:09 +1000 | [diff] [blame] | 29 | #include <sys/stat.h> |
| 30 | #include <sys/uio.h> |
Damien Miller | 9f2abc4 | 2006-07-10 20:53:08 +1000 | [diff] [blame] | 31 | |
Darren Tucker | 4230a5d | 2008-07-02 22:56:09 +1000 | [diff] [blame] | 32 | #include <fcntl.h> |
Damien Miller | 9f2abc4 | 2006-07-10 20:53:08 +1000 | [diff] [blame] | 33 | #include <pwd.h> |
Damien Miller | d783435 | 2006-08-05 12:39:39 +1000 | [diff] [blame] | 34 | #include <stdarg.h> |
Damien Miller | e3476ed | 2006-07-24 14:13:33 +1000 | [diff] [blame] | 35 | #include <string.h> |
Darren Tucker | 4230a5d | 2008-07-02 22:56:09 +1000 | [diff] [blame] | 36 | #include <unistd.h> |
Damien Miller | 9f2abc4 | 2006-07-10 20:53:08 +1000 | [diff] [blame] | 37 | |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 38 | #include "xmalloc.h" |
Damien Miller | 0b4d48b | 2008-07-05 09:44:53 +1000 | [diff] [blame^] | 39 | #include "atomicio.h" |
Damien Miller | d783435 | 2006-08-05 12:39:39 +1000 | [diff] [blame] | 40 | #include "ssh2.h" |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 41 | #include "packet.h" |
Ben Lindstrom | 226cfa0 | 2001-01-22 05:34:40 +0000 | [diff] [blame] | 42 | #include "log.h" |
Damien Miller | d783435 | 2006-08-05 12:39:39 +1000 | [diff] [blame] | 43 | #include "buffer.h" |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 44 | #include "servconf.h" |
| 45 | #include "compat.h" |
Damien Miller | d783435 | 2006-08-05 12:39:39 +1000 | [diff] [blame] | 46 | #include "key.h" |
| 47 | #include "hostfile.h" |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 48 | #include "auth.h" |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 49 | #include "dispatch.h" |
Ben Lindstrom | 226cfa0 | 2001-01-22 05:34:40 +0000 | [diff] [blame] | 50 | #include "pathnames.h" |
Darren Tucker | 77fc29e | 2004-09-11 23:07:03 +1000 | [diff] [blame] | 51 | #include "buffer.h" |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 52 | |
Darren Tucker | 0efd155 | 2003-08-26 11:49:55 +1000 | [diff] [blame] | 53 | #ifdef GSSAPI |
| 54 | #include "ssh-gss.h" |
| 55 | #endif |
Damien Miller | d783435 | 2006-08-05 12:39:39 +1000 | [diff] [blame] | 56 | #include "monitor_wrap.h" |
Darren Tucker | 0efd155 | 2003-08-26 11:49:55 +1000 | [diff] [blame] | 57 | |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 58 | /* import */ |
| 59 | extern ServerOptions options; |
Ben Lindstrom | 46c1622 | 2000-12-22 01:43:59 +0000 | [diff] [blame] | 60 | extern u_char *session_id2; |
Darren Tucker | 502d384 | 2003-06-28 12:38:01 +1000 | [diff] [blame] | 61 | extern u_int session_id2_len; |
Darren Tucker | 77fc29e | 2004-09-11 23:07:03 +1000 | [diff] [blame] | 62 | extern Buffer loginmsg; |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 63 | |
Ben Lindstrom | 511bb24 | 2002-06-06 20:52:37 +0000 | [diff] [blame] | 64 | /* methods */ |
| 65 | |
| 66 | extern Authmethod method_none; |
| 67 | extern Authmethod method_pubkey; |
| 68 | extern Authmethod method_passwd; |
| 69 | extern Authmethod method_kbdint; |
| 70 | extern Authmethod method_hostbased; |
Darren Tucker | 0efd155 | 2003-08-26 11:49:55 +1000 | [diff] [blame] | 71 | #ifdef GSSAPI |
| 72 | extern Authmethod method_gssapi; |
| 73 | #endif |
Ben Lindstrom | 511bb24 | 2002-06-06 20:52:37 +0000 | [diff] [blame] | 74 | |
| 75 | Authmethod *authmethods[] = { |
| 76 | &method_none, |
| 77 | &method_pubkey, |
Darren Tucker | 0efd155 | 2003-08-26 11:49:55 +1000 | [diff] [blame] | 78 | #ifdef GSSAPI |
| 79 | &method_gssapi, |
| 80 | #endif |
Ben Lindstrom | 511bb24 | 2002-06-06 20:52:37 +0000 | [diff] [blame] | 81 | &method_passwd, |
| 82 | &method_kbdint, |
| 83 | &method_hostbased, |
| 84 | NULL |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 85 | }; |
| 86 | |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 87 | /* protocol */ |
| 88 | |
Damien Miller | 630d6f4 | 2002-01-22 23:17:30 +1100 | [diff] [blame] | 89 | static void input_service_request(int, u_int32_t, void *); |
| 90 | static void input_userauth_request(int, u_int32_t, void *); |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 91 | |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 92 | /* helper */ |
Ben Lindstrom | bba8121 | 2001-06-25 05:01:22 +0000 | [diff] [blame] | 93 | static Authmethod *authmethod_lookup(const char *); |
Ben Lindstrom | 7907382 | 2001-07-04 03:42:30 +0000 | [diff] [blame] | 94 | static char *authmethods_get(void); |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 95 | |
Darren Tucker | 4230a5d | 2008-07-02 22:56:09 +1000 | [diff] [blame] | 96 | char * |
| 97 | auth2_read_banner(void) |
| 98 | { |
| 99 | struct stat st; |
| 100 | char *banner = NULL; |
| 101 | size_t len, n; |
| 102 | int fd; |
| 103 | |
| 104 | if ((fd = open(options.banner, O_RDONLY)) == -1) |
| 105 | return (NULL); |
| 106 | if (fstat(fd, &st) == -1) { |
| 107 | close(fd); |
| 108 | return (NULL); |
| 109 | } |
| 110 | if (st.st_size > 1*1024*1024) { |
| 111 | close(fd); |
| 112 | return (NULL); |
| 113 | } |
| 114 | |
| 115 | len = (size_t)st.st_size; /* truncate */ |
| 116 | banner = xmalloc(len + 1); |
| 117 | n = atomicio(read, fd, banner, len); |
| 118 | close(fd); |
| 119 | |
| 120 | if (n != len) { |
| 121 | xfree(banner); |
| 122 | return (NULL); |
| 123 | } |
| 124 | banner[n] = '\0'; |
| 125 | |
| 126 | return (banner); |
| 127 | } |
| 128 | |
| 129 | void |
| 130 | userauth_send_banner(const char *msg) |
| 131 | { |
| 132 | if (datafellows & SSH_BUG_BANNER) |
| 133 | return; |
| 134 | |
| 135 | packet_start(SSH2_MSG_USERAUTH_BANNER); |
| 136 | packet_put_cstring(msg); |
| 137 | packet_put_cstring(""); /* language, unused */ |
| 138 | packet_send(); |
| 139 | debug("%s: sent", __func__); |
| 140 | } |
| 141 | |
| 142 | static void |
| 143 | userauth_banner(void) |
| 144 | { |
| 145 | char *banner = NULL; |
| 146 | |
| 147 | if (options.banner == NULL || |
| 148 | strcasecmp(options.banner, "none") == 0 || |
| 149 | (datafellows & SSH_BUG_BANNER) != 0) |
| 150 | return; |
| 151 | |
| 152 | if ((banner = PRIVSEP(auth2_read_banner())) == NULL) |
| 153 | goto done; |
| 154 | userauth_send_banner(banner); |
| 155 | |
| 156 | done: |
| 157 | if (banner) |
| 158 | xfree(banner); |
| 159 | } |
| 160 | |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 161 | /* |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 162 | * loop until authctxt->success == TRUE |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 163 | */ |
Darren Tucker | 3e33cec | 2003-10-02 16:12:36 +1000 | [diff] [blame] | 164 | void |
| 165 | do_authentication2(Authctxt *authctxt) |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 166 | { |
Damien Miller | 7d05339 | 2002-01-22 23:24:13 +1100 | [diff] [blame] | 167 | dispatch_init(&dispatch_protocol_error); |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 168 | dispatch_set(SSH2_MSG_SERVICE_REQUEST, &input_service_request); |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 169 | dispatch_run(DISPATCH_BLOCK, &authctxt->success, authctxt); |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 170 | } |
| 171 | |
Damien Miller | 91d4b12 | 2006-03-26 14:05:20 +1100 | [diff] [blame] | 172 | /*ARGSUSED*/ |
Ben Lindstrom | bba8121 | 2001-06-25 05:01:22 +0000 | [diff] [blame] | 173 | static void |
Damien Miller | 630d6f4 | 2002-01-22 23:17:30 +1100 | [diff] [blame] | 174 | input_service_request(int type, u_int32_t seq, void *ctxt) |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 175 | { |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 176 | Authctxt *authctxt = ctxt; |
Ben Lindstrom | 46c1622 | 2000-12-22 01:43:59 +0000 | [diff] [blame] | 177 | u_int len; |
Ben Lindstrom | 5a9d0ea | 2002-07-04 00:12:53 +0000 | [diff] [blame] | 178 | int acceptit = 0; |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 179 | char *service = packet_get_string(&len); |
Damien Miller | 48b03fc | 2002-01-22 23:11:40 +1100 | [diff] [blame] | 180 | packet_check_eom(); |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 181 | |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 182 | if (authctxt == NULL) |
| 183 | fatal("input_service_request: no authctxt"); |
| 184 | |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 185 | if (strcmp(service, "ssh-userauth") == 0) { |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 186 | if (!authctxt->success) { |
Ben Lindstrom | 5a9d0ea | 2002-07-04 00:12:53 +0000 | [diff] [blame] | 187 | acceptit = 1; |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 188 | /* now we can handle user-auth requests */ |
| 189 | dispatch_set(SSH2_MSG_USERAUTH_REQUEST, &input_userauth_request); |
| 190 | } |
| 191 | } |
| 192 | /* XXX all other service requests are denied */ |
| 193 | |
Ben Lindstrom | 5a9d0ea | 2002-07-04 00:12:53 +0000 | [diff] [blame] | 194 | if (acceptit) { |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 195 | packet_start(SSH2_MSG_SERVICE_ACCEPT); |
| 196 | packet_put_cstring(service); |
| 197 | packet_send(); |
| 198 | packet_write_wait(); |
| 199 | } else { |
| 200 | debug("bad service request %s", service); |
| 201 | packet_disconnect("bad service request %s", service); |
| 202 | } |
| 203 | xfree(service); |
| 204 | } |
| 205 | |
Damien Miller | 91d4b12 | 2006-03-26 14:05:20 +1100 | [diff] [blame] | 206 | /*ARGSUSED*/ |
Ben Lindstrom | bba8121 | 2001-06-25 05:01:22 +0000 | [diff] [blame] | 207 | static void |
Damien Miller | 630d6f4 | 2002-01-22 23:17:30 +1100 | [diff] [blame] | 208 | input_userauth_request(int type, u_int32_t seq, void *ctxt) |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 209 | { |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 210 | Authctxt *authctxt = ctxt; |
| 211 | Authmethod *m = NULL; |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 212 | char *user, *service, *method, *style = NULL; |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 213 | int authenticated = 0; |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 214 | |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 215 | if (authctxt == NULL) |
| 216 | fatal("input_userauth_request: no authctxt"); |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 217 | |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 218 | user = packet_get_string(NULL); |
| 219 | service = packet_get_string(NULL); |
| 220 | method = packet_get_string(NULL); |
| 221 | debug("userauth-request for user %s service %s method %s", user, service, method); |
Ben Lindstrom | 4dccfa5 | 2000-12-28 16:40:05 +0000 | [diff] [blame] | 222 | debug("attempt %d failures %d", authctxt->attempt, authctxt->failures); |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 223 | |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 224 | if ((style = strchr(user, ':')) != NULL) |
| 225 | *style++ = 0; |
| 226 | |
Kevin Steves | ef4eea9 | 2001-02-05 12:42:17 +0000 | [diff] [blame] | 227 | if (authctxt->attempt++ == 0) { |
Damien Miller | 3a5b023 | 2002-03-13 13:19:42 +1100 | [diff] [blame] | 228 | /* setup auth context */ |
Kevin Steves | 205cc1e | 2002-03-22 20:43:05 +0000 | [diff] [blame] | 229 | authctxt->pw = PRIVSEP(getpwnamallow(user)); |
Darren Tucker | dbf7a74 | 2004-03-08 23:04:06 +1100 | [diff] [blame] | 230 | authctxt->user = xstrdup(user); |
Kevin Steves | 205cc1e | 2002-03-22 20:43:05 +0000 | [diff] [blame] | 231 | if (authctxt->pw && strcmp(service, "ssh-connection")==0) { |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 232 | authctxt->valid = 1; |
| 233 | debug2("input_userauth_request: setting up authctxt for %s", user); |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 234 | } else { |
Darren Tucker | 5cb30ad | 2004-08-12 22:40:24 +1000 | [diff] [blame] | 235 | logit("input_userauth_request: invalid user %s", user); |
Damien Miller | 856f0be | 2003-09-03 07:32:45 +1000 | [diff] [blame] | 236 | authctxt->pw = fakepw(); |
Darren Tucker | 2e0cf0d | 2005-02-08 21:52:47 +1100 | [diff] [blame] | 237 | #ifdef SSH_AUDIT_EVENTS |
| 238 | PRIVSEP(audit_event(SSH_INVALID_USER)); |
Darren Tucker | 269a1ea | 2005-02-03 00:20:53 +1100 | [diff] [blame] | 239 | #endif |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 240 | } |
Darren Tucker | d3eff2b | 2005-09-24 12:43:51 +1000 | [diff] [blame] | 241 | #ifdef USE_PAM |
| 242 | if (options.use_pam) |
| 243 | PRIVSEP(start_pam(authctxt)); |
| 244 | #endif |
Damien Miller | 30d1f84 | 2004-07-21 20:48:53 +1000 | [diff] [blame] | 245 | setproctitle("%s%s", authctxt->valid ? user : "unknown", |
Ben Lindstrom | 7a2073c | 2002-03-22 02:30:41 +0000 | [diff] [blame] | 246 | use_privsep ? " [net]" : ""); |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 247 | authctxt->service = xstrdup(service); |
Ben Lindstrom | 9d0c066 | 2001-06-09 01:40:00 +0000 | [diff] [blame] | 248 | authctxt->style = style ? xstrdup(style) : NULL; |
Ben Lindstrom | 7a2073c | 2002-03-22 02:30:41 +0000 | [diff] [blame] | 249 | if (use_privsep) |
| 250 | mm_inform_authserv(service, style); |
Darren Tucker | 4230a5d | 2008-07-02 22:56:09 +1000 | [diff] [blame] | 251 | userauth_banner(); |
Ben Lindstrom | 9d0c066 | 2001-06-09 01:40:00 +0000 | [diff] [blame] | 252 | } else if (strcmp(user, authctxt->user) != 0 || |
| 253 | strcmp(service, authctxt->service) != 0) { |
| 254 | packet_disconnect("Change of username or service not allowed: " |
| 255 | "(%s,%s) -> (%s,%s)", |
| 256 | authctxt->user, authctxt->service, user, service); |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 257 | } |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 258 | /* reset state */ |
Damien Miller | ee11625 | 2001-12-21 12:42:34 +1100 | [diff] [blame] | 259 | auth2_challenge_stop(authctxt); |
Darren Tucker | 0efd155 | 2003-08-26 11:49:55 +1000 | [diff] [blame] | 260 | |
| 261 | #ifdef GSSAPI |
| 262 | dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, NULL); |
| 263 | dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE, NULL); |
| 264 | #endif |
| 265 | |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 266 | authctxt->postponed = 0; |
Damien Miller | b70b61f | 2000-09-16 16:25:12 +1100 | [diff] [blame] | 267 | |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 268 | /* try to authenticate user */ |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 269 | m = authmethod_lookup(method); |
Darren Tucker | 4230a5d | 2008-07-02 22:56:09 +1000 | [diff] [blame] | 270 | if (m != NULL && authctxt->failures < options.max_authtries) { |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 271 | debug2("input_userauth_request: try method %s", method); |
| 272 | authenticated = m->userauth(authctxt); |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 273 | } |
Damien Miller | 5d57e50 | 2001-03-30 10:48:31 +1000 | [diff] [blame] | 274 | userauth_finish(authctxt, authenticated, method); |
| 275 | |
| 276 | xfree(service); |
| 277 | xfree(user); |
| 278 | xfree(method); |
| 279 | } |
| 280 | |
| 281 | void |
| 282 | userauth_finish(Authctxt *authctxt, int authenticated, char *method) |
| 283 | { |
Ben Lindstrom | cd4349f | 2001-06-09 00:23:17 +0000 | [diff] [blame] | 284 | char *methods; |
| 285 | |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 286 | if (!authctxt->valid && authenticated) |
| 287 | fatal("INTERNAL ERROR: authenticated invalid user %s", |
| 288 | authctxt->user); |
Damien Miller | b70b61f | 2000-09-16 16:25:12 +1100 | [diff] [blame] | 289 | |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 290 | /* Special handling for root */ |
Damien Miller | 556f931 | 2003-02-24 11:59:26 +1100 | [diff] [blame] | 291 | if (authenticated && authctxt->pw->pw_uid == 0 && |
Darren Tucker | 269a1ea | 2005-02-03 00:20:53 +1100 | [diff] [blame] | 292 | !auth_root_allowed(method)) { |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 293 | authenticated = 0; |
Darren Tucker | 2e0cf0d | 2005-02-08 21:52:47 +1100 | [diff] [blame] | 294 | #ifdef SSH_AUDIT_EVENTS |
| 295 | PRIVSEP(audit_event(SSH_LOGIN_ROOT_DENIED)); |
Darren Tucker | 269a1ea | 2005-02-03 00:20:53 +1100 | [diff] [blame] | 296 | #endif |
| 297 | } |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 298 | |
Damien Miller | 1f499fd | 2003-08-25 13:08:49 +1000 | [diff] [blame] | 299 | #ifdef USE_PAM |
Darren Tucker | 77fc29e | 2004-09-11 23:07:03 +1000 | [diff] [blame] | 300 | if (options.use_pam && authenticated) { |
| 301 | if (!PRIVSEP(do_pam_account())) { |
Darren Tucker | 77fc29e | 2004-09-11 23:07:03 +1000 | [diff] [blame] | 302 | /* if PAM returned a message, send it to the user */ |
| 303 | if (buffer_len(&loginmsg) > 0) { |
| 304 | buffer_append(&loginmsg, "\0", 1); |
| 305 | userauth_send_banner(buffer_ptr(&loginmsg)); |
Darren Tucker | c138667 | 2004-12-03 14:33:47 +1100 | [diff] [blame] | 306 | packet_write_wait(); |
Darren Tucker | 77fc29e | 2004-09-11 23:07:03 +1000 | [diff] [blame] | 307 | } |
Darren Tucker | c138667 | 2004-12-03 14:33:47 +1100 | [diff] [blame] | 308 | fatal("Access denied for user %s by PAM account " |
Damien Miller | b6f72f5 | 2005-07-17 17:26:43 +1000 | [diff] [blame] | 309 | "configuration", authctxt->user); |
Darren Tucker | 77fc29e | 2004-09-11 23:07:03 +1000 | [diff] [blame] | 310 | } |
| 311 | } |
Damien Miller | 1f499fd | 2003-08-25 13:08:49 +1000 | [diff] [blame] | 312 | #endif |
| 313 | |
Tim Rice | 81ed518 | 2002-09-25 17:38:46 -0700 | [diff] [blame] | 314 | #ifdef _UNICOS |
| 315 | if (authenticated && cray_access_denied(authctxt->user)) { |
| 316 | authenticated = 0; |
| 317 | fatal("Access denied for user %s.",authctxt->user); |
| 318 | } |
| 319 | #endif /* _UNICOS */ |
| 320 | |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 321 | /* Log before sending the reply */ |
Ben Lindstrom | db65e8f | 2001-01-19 04:26:52 +0000 | [diff] [blame] | 322 | auth_log(authctxt, authenticated, method, " ssh2"); |
| 323 | |
Ben Lindstrom | cd4349f | 2001-06-09 00:23:17 +0000 | [diff] [blame] | 324 | if (authctxt->postponed) |
| 325 | return; |
| 326 | |
| 327 | /* XXX todo: check if multiple auth methods are needed */ |
| 328 | if (authenticated == 1) { |
| 329 | /* turn off userauth */ |
Damien Miller | 7d05339 | 2002-01-22 23:24:13 +1100 | [diff] [blame] | 330 | dispatch_set(SSH2_MSG_USERAUTH_REQUEST, &dispatch_protocol_ignore); |
Ben Lindstrom | cd4349f | 2001-06-09 00:23:17 +0000 | [diff] [blame] | 331 | packet_start(SSH2_MSG_USERAUTH_SUCCESS); |
| 332 | packet_send(); |
| 333 | packet_write_wait(); |
| 334 | /* now we can break out */ |
| 335 | authctxt->success = 1; |
| 336 | } else { |
Damien Miller | 0b4d48b | 2008-07-05 09:44:53 +1000 | [diff] [blame^] | 337 | |
| 338 | /* Allow initial try of "none" auth without failure penalty */ |
| 339 | if (authctxt->attempt > 1 || strcmp(method, "none") != 0) |
| 340 | authctxt->failures++; |
| 341 | if (authctxt->failures >= options.max_authtries) { |
Darren Tucker | 2e0cf0d | 2005-02-08 21:52:47 +1100 | [diff] [blame] | 342 | #ifdef SSH_AUDIT_EVENTS |
| 343 | PRIVSEP(audit_event(SSH_LOGIN_EXCEED_MAXTRIES)); |
Darren Tucker | 269a1ea | 2005-02-03 00:20:53 +1100 | [diff] [blame] | 344 | #endif |
Ben Lindstrom | cd4349f | 2001-06-09 00:23:17 +0000 | [diff] [blame] | 345 | packet_disconnect(AUTH_FAIL_MSG, authctxt->user); |
Darren Tucker | 269a1ea | 2005-02-03 00:20:53 +1100 | [diff] [blame] | 346 | } |
Ben Lindstrom | cd4349f | 2001-06-09 00:23:17 +0000 | [diff] [blame] | 347 | methods = authmethods_get(); |
| 348 | packet_start(SSH2_MSG_USERAUTH_FAILURE); |
| 349 | packet_put_cstring(methods); |
| 350 | packet_put_char(0); /* XXX partial success, unused */ |
| 351 | packet_send(); |
| 352 | packet_write_wait(); |
| 353 | xfree(methods); |
| 354 | } |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 355 | } |
| 356 | |
Ben Lindstrom | 7907382 | 2001-07-04 03:42:30 +0000 | [diff] [blame] | 357 | static char * |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 358 | authmethods_get(void) |
| 359 | { |
Damien Miller | 0e3b872 | 2002-01-22 23:26:38 +1100 | [diff] [blame] | 360 | Buffer b; |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 361 | char *list; |
Ben Lindstrom | 511bb24 | 2002-06-06 20:52:37 +0000 | [diff] [blame] | 362 | int i; |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 363 | |
Damien Miller | 0e3b872 | 2002-01-22 23:26:38 +1100 | [diff] [blame] | 364 | buffer_init(&b); |
Ben Lindstrom | 511bb24 | 2002-06-06 20:52:37 +0000 | [diff] [blame] | 365 | for (i = 0; authmethods[i] != NULL; i++) { |
| 366 | if (strcmp(authmethods[i]->name, "none") == 0) |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 367 | continue; |
Ben Lindstrom | 511bb24 | 2002-06-06 20:52:37 +0000 | [diff] [blame] | 368 | if (authmethods[i]->enabled != NULL && |
| 369 | *(authmethods[i]->enabled) != 0) { |
Damien Miller | 0e3b872 | 2002-01-22 23:26:38 +1100 | [diff] [blame] | 370 | if (buffer_len(&b) > 0) |
| 371 | buffer_append(&b, ",", 1); |
Ben Lindstrom | 511bb24 | 2002-06-06 20:52:37 +0000 | [diff] [blame] | 372 | buffer_append(&b, authmethods[i]->name, |
| 373 | strlen(authmethods[i]->name)); |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 374 | } |
| 375 | } |
Damien Miller | 0e3b872 | 2002-01-22 23:26:38 +1100 | [diff] [blame] | 376 | buffer_append(&b, "\0", 1); |
| 377 | list = xstrdup(buffer_ptr(&b)); |
| 378 | buffer_free(&b); |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 379 | return list; |
| 380 | } |
| 381 | |
Ben Lindstrom | bba8121 | 2001-06-25 05:01:22 +0000 | [diff] [blame] | 382 | static Authmethod * |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 383 | authmethod_lookup(const char *name) |
| 384 | { |
Ben Lindstrom | 511bb24 | 2002-06-06 20:52:37 +0000 | [diff] [blame] | 385 | int i; |
| 386 | |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 387 | if (name != NULL) |
Ben Lindstrom | 511bb24 | 2002-06-06 20:52:37 +0000 | [diff] [blame] | 388 | for (i = 0; authmethods[i] != NULL; i++) |
| 389 | if (authmethods[i]->enabled != NULL && |
| 390 | *(authmethods[i]->enabled) != 0 && |
| 391 | strcmp(name, authmethods[i]->name) == 0) |
| 392 | return authmethods[i]; |
| 393 | debug2("Unrecognized authentication method name: %s", |
| 394 | name ? name : "NULL"); |
Damien Miller | 874d77b | 2000-10-14 16:23:11 +1100 | [diff] [blame] | 395 | return NULL; |
Damien Miller | eba71ba | 2000-04-29 23:57:08 +1000 | [diff] [blame] | 396 | } |
Darren Tucker | 4230a5d | 2008-07-02 22:56:09 +1000 | [diff] [blame] | 397 | |