Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1 | /* $OpenBSD: sshconnect2.c,v 1.223 2015/01/30 11:43:14 djm Exp $ */ |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 2 | /* |
| 3 | * Copyright (c) 2000 Markus Friedl. All rights reserved. |
| 4 | * Copyright (c) 2008 Damien Miller. All rights reserved. |
| 5 | * |
| 6 | * Redistribution and use in source and binary forms, with or without |
| 7 | * modification, are permitted provided that the following conditions |
| 8 | * are met: |
| 9 | * 1. Redistributions of source code must retain the above copyright |
| 10 | * notice, this list of conditions and the following disclaimer. |
| 11 | * 2. Redistributions in binary form must reproduce the above copyright |
| 12 | * notice, this list of conditions and the following disclaimer in the |
| 13 | * documentation and/or other materials provided with the distribution. |
| 14 | * |
| 15 | * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
| 16 | * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| 17 | * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| 18 | * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
| 19 | * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| 20 | * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| 21 | * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| 22 | * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| 23 | * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| 24 | * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| 25 | */ |
| 26 | |
| 27 | #include "includes.h" |
| 28 | |
| 29 | #include <sys/types.h> |
| 30 | #include <sys/socket.h> |
| 31 | #include <sys/wait.h> |
| 32 | #include <sys/stat.h> |
| 33 | |
| 34 | #include <errno.h> |
| 35 | #include <fcntl.h> |
| 36 | #include <netdb.h> |
| 37 | #include <pwd.h> |
| 38 | #include <signal.h> |
| 39 | #include <stdarg.h> |
| 40 | #include <stdio.h> |
| 41 | #include <string.h> |
| 42 | #include <unistd.h> |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 43 | #if defined(HAVE_STRNVIS) && defined(HAVE_VIS_H) && !defined(BROKEN_STRNVIS) |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 44 | #include <vis.h> |
| 45 | #endif |
| 46 | |
| 47 | #include "openbsd-compat/sys-queue.h" |
| 48 | |
| 49 | #include "xmalloc.h" |
| 50 | #include "ssh.h" |
| 51 | #include "ssh2.h" |
| 52 | #include "buffer.h" |
| 53 | #include "packet.h" |
| 54 | #include "compat.h" |
| 55 | #include "cipher.h" |
| 56 | #include "key.h" |
| 57 | #include "kex.h" |
| 58 | #include "myproposal.h" |
| 59 | #include "sshconnect.h" |
| 60 | #include "authfile.h" |
| 61 | #include "dh.h" |
| 62 | #include "authfd.h" |
| 63 | #include "log.h" |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 64 | #include "misc.h" |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 65 | #include "readconf.h" |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 66 | #include "match.h" |
| 67 | #include "dispatch.h" |
| 68 | #include "canohost.h" |
| 69 | #include "msg.h" |
| 70 | #include "pathnames.h" |
| 71 | #include "uidswap.h" |
| 72 | #include "hostfile.h" |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 73 | #include "ssherr.h" |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 74 | |
| 75 | #ifdef GSSAPI |
| 76 | #include "ssh-gss.h" |
| 77 | #endif |
| 78 | |
| 79 | /* import */ |
| 80 | extern char *client_version_string; |
| 81 | extern char *server_version_string; |
| 82 | extern Options options; |
| 83 | |
| 84 | /* |
| 85 | * SSH2 key exchange |
| 86 | */ |
| 87 | |
| 88 | u_char *session_id2 = NULL; |
| 89 | u_int session_id2_len = 0; |
| 90 | |
| 91 | char *xxx_host; |
| 92 | struct sockaddr *xxx_hostaddr; |
| 93 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 94 | static int |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 95 | verify_host_key_callback(Key *hostkey, struct ssh *ssh) |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 96 | { |
| 97 | if (verify_host_key(xxx_host, xxx_hostaddr, hostkey) == -1) |
| 98 | fatal("Host key verification failed."); |
| 99 | return 0; |
| 100 | } |
| 101 | |
| 102 | static char * |
| 103 | order_hostkeyalgs(char *host, struct sockaddr *hostaddr, u_short port) |
| 104 | { |
| 105 | char *oavail, *avail, *first, *last, *alg, *hostname, *ret; |
| 106 | size_t maxlen; |
| 107 | struct hostkeys *hostkeys; |
| 108 | int ktype; |
| 109 | u_int i; |
| 110 | |
| 111 | /* Find all hostkeys for this hostname */ |
| 112 | get_hostfile_hostname_ipaddr(host, hostaddr, port, &hostname, NULL); |
| 113 | hostkeys = init_hostkeys(); |
| 114 | for (i = 0; i < options.num_user_hostfiles; i++) |
| 115 | load_hostkeys(hostkeys, hostname, options.user_hostfiles[i]); |
| 116 | for (i = 0; i < options.num_system_hostfiles; i++) |
| 117 | load_hostkeys(hostkeys, hostname, options.system_hostfiles[i]); |
| 118 | |
| 119 | oavail = avail = xstrdup(KEX_DEFAULT_PK_ALG); |
| 120 | maxlen = strlen(avail) + 1; |
| 121 | first = xmalloc(maxlen); |
| 122 | last = xmalloc(maxlen); |
| 123 | *first = *last = '\0'; |
| 124 | |
| 125 | #define ALG_APPEND(to, from) \ |
| 126 | do { \ |
| 127 | if (*to != '\0') \ |
| 128 | strlcat(to, ",", maxlen); \ |
| 129 | strlcat(to, from, maxlen); \ |
| 130 | } while (0) |
| 131 | |
| 132 | while ((alg = strsep(&avail, ",")) && *alg != '\0') { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 133 | if ((ktype = sshkey_type_from_name(alg)) == KEY_UNSPEC) |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 134 | fatal("%s: unknown alg %s", __func__, alg); |
| 135 | if (lookup_key_in_hostkeys_by_type(hostkeys, |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 136 | sshkey_type_plain(ktype), NULL)) |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 137 | ALG_APPEND(first, alg); |
| 138 | else |
| 139 | ALG_APPEND(last, alg); |
| 140 | } |
| 141 | #undef ALG_APPEND |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 142 | xasprintf(&ret, "%s%s%s", first, |
| 143 | (*first == '\0' || *last == '\0') ? "" : ",", last); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 144 | if (*first != '\0') |
| 145 | debug3("%s: prefer hostkeyalgs: %s", __func__, first); |
| 146 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 147 | free(first); |
| 148 | free(last); |
| 149 | free(hostname); |
| 150 | free(oavail); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 151 | free_hostkeys(hostkeys); |
| 152 | |
| 153 | return ret; |
| 154 | } |
| 155 | |
| 156 | void |
| 157 | ssh_kex2(char *host, struct sockaddr *hostaddr, u_short port) |
| 158 | { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 159 | char *myproposal[PROPOSAL_MAX] = { KEX_CLIENT }; |
| 160 | struct kex *kex; |
| 161 | int r; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 162 | |
| 163 | xxx_host = host; |
| 164 | xxx_hostaddr = hostaddr; |
| 165 | |
| 166 | if (options.ciphers == (char *)-1) { |
| 167 | logit("No valid ciphers for protocol version 2 given, using defaults."); |
| 168 | options.ciphers = NULL; |
| 169 | } |
| 170 | if (options.ciphers != NULL) { |
| 171 | myproposal[PROPOSAL_ENC_ALGS_CTOS] = |
| 172 | myproposal[PROPOSAL_ENC_ALGS_STOC] = options.ciphers; |
| 173 | } |
| 174 | myproposal[PROPOSAL_ENC_ALGS_CTOS] = |
| 175 | compat_cipher_proposal(myproposal[PROPOSAL_ENC_ALGS_CTOS]); |
| 176 | myproposal[PROPOSAL_ENC_ALGS_STOC] = |
| 177 | compat_cipher_proposal(myproposal[PROPOSAL_ENC_ALGS_STOC]); |
| 178 | if (options.compression) { |
| 179 | myproposal[PROPOSAL_COMP_ALGS_CTOS] = |
| 180 | myproposal[PROPOSAL_COMP_ALGS_STOC] = "zlib@openssh.com,zlib,none"; |
| 181 | } else { |
| 182 | myproposal[PROPOSAL_COMP_ALGS_CTOS] = |
| 183 | myproposal[PROPOSAL_COMP_ALGS_STOC] = "none,zlib@openssh.com,zlib"; |
| 184 | } |
| 185 | if (options.macs != NULL) { |
| 186 | myproposal[PROPOSAL_MAC_ALGS_CTOS] = |
| 187 | myproposal[PROPOSAL_MAC_ALGS_STOC] = options.macs; |
| 188 | } |
| 189 | if (options.hostkeyalgorithms != NULL) |
| 190 | myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] = |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 191 | compat_pkalg_proposal(options.hostkeyalgorithms); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 192 | else { |
| 193 | /* Prefer algorithms that we already have keys for */ |
| 194 | myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] = |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 195 | compat_pkalg_proposal( |
| 196 | order_hostkeyalgs(host, hostaddr, port)); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 197 | } |
| 198 | if (options.kex_algorithms != NULL) |
| 199 | myproposal[PROPOSAL_KEX_ALGS] = options.kex_algorithms; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 200 | myproposal[PROPOSAL_KEX_ALGS] = compat_kex_proposal( |
| 201 | myproposal[PROPOSAL_KEX_ALGS]); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 202 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 203 | if (options.rekey_limit || options.rekey_interval) |
| 204 | packet_set_rekey_limits((u_int32_t)options.rekey_limit, |
| 205 | (time_t)options.rekey_interval); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 206 | |
| 207 | /* start key exchange */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 208 | if ((r = kex_setup(active_state, myproposal)) != 0) |
| 209 | fatal("kex_setup: %s", ssh_err(r)); |
| 210 | kex = active_state->kex; |
| 211 | #ifdef WITH_OPENSSL |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 212 | kex->kex[KEX_DH_GRP1_SHA1] = kexdh_client; |
| 213 | kex->kex[KEX_DH_GRP14_SHA1] = kexdh_client; |
| 214 | kex->kex[KEX_DH_GEX_SHA1] = kexgex_client; |
| 215 | kex->kex[KEX_DH_GEX_SHA256] = kexgex_client; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 216 | # ifdef OPENSSL_HAS_ECC |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 217 | kex->kex[KEX_ECDH_SHA2] = kexecdh_client; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 218 | # endif |
| 219 | #endif |
| 220 | kex->kex[KEX_C25519_SHA256] = kexc25519_client; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 221 | kex->client_version_string=client_version_string; |
| 222 | kex->server_version_string=server_version_string; |
| 223 | kex->verify_host_key=&verify_host_key_callback; |
| 224 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 225 | dispatch_run(DISPATCH_BLOCK, &kex->done, active_state); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 226 | |
| 227 | if (options.use_roaming && !kex->roaming) { |
| 228 | debug("Roaming not allowed by server"); |
| 229 | options.use_roaming = 0; |
| 230 | } |
| 231 | |
| 232 | session_id2 = kex->session_id; |
| 233 | session_id2_len = kex->session_id_len; |
| 234 | |
| 235 | #ifdef DEBUG_KEXDH |
| 236 | /* send 1st encrypted/maced/compressed message */ |
| 237 | packet_start(SSH2_MSG_IGNORE); |
| 238 | packet_put_cstring("markus"); |
| 239 | packet_send(); |
| 240 | packet_write_wait(); |
| 241 | #endif |
| 242 | } |
| 243 | |
| 244 | /* |
| 245 | * Authenticate user |
| 246 | */ |
| 247 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 248 | typedef struct cauthctxt Authctxt; |
| 249 | typedef struct cauthmethod Authmethod; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 250 | typedef struct identity Identity; |
| 251 | typedef struct idlist Idlist; |
| 252 | |
| 253 | struct identity { |
| 254 | TAILQ_ENTRY(identity) next; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 255 | int agent_fd; /* >=0 if agent supports key */ |
| 256 | struct sshkey *key; /* public/private key */ |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 257 | char *filename; /* comment for agent-only keys */ |
| 258 | int tried; |
| 259 | int isprivate; /* key points to the private key */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 260 | int userprovided; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 261 | }; |
| 262 | TAILQ_HEAD(idlist, identity); |
| 263 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 264 | struct cauthctxt { |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 265 | const char *server_user; |
| 266 | const char *local_user; |
| 267 | const char *host; |
| 268 | const char *service; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 269 | struct cauthmethod *method; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 270 | sig_atomic_t success; |
| 271 | char *authlist; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 272 | int attempt; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 273 | /* pubkey */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 274 | struct idlist keys; |
| 275 | int agent_fd; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 276 | /* hostbased */ |
| 277 | Sensitive *sensitive; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 278 | char *oktypes, *ktypes; |
| 279 | const char *active_ktype; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 280 | /* kbd-interactive */ |
| 281 | int info_req_seen; |
| 282 | /* generic */ |
| 283 | void *methoddata; |
| 284 | }; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 285 | |
| 286 | struct cauthmethod { |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 287 | char *name; /* string to compare against server's list */ |
| 288 | int (*userauth)(Authctxt *authctxt); |
| 289 | void (*cleanup)(Authctxt *authctxt); |
| 290 | int *enabled; /* flag in option struct that enables method */ |
| 291 | int *batch_flag; /* flag in option struct that disables method */ |
| 292 | }; |
| 293 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 294 | int input_userauth_success(int, u_int32_t, void *); |
| 295 | int input_userauth_success_unexpected(int, u_int32_t, void *); |
| 296 | int input_userauth_failure(int, u_int32_t, void *); |
| 297 | int input_userauth_banner(int, u_int32_t, void *); |
| 298 | int input_userauth_error(int, u_int32_t, void *); |
| 299 | int input_userauth_info_req(int, u_int32_t, void *); |
| 300 | int input_userauth_pk_ok(int, u_int32_t, void *); |
| 301 | int input_userauth_passwd_changereq(int, u_int32_t, void *); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 302 | |
| 303 | int userauth_none(Authctxt *); |
| 304 | int userauth_pubkey(Authctxt *); |
| 305 | int userauth_passwd(Authctxt *); |
| 306 | int userauth_kbdint(Authctxt *); |
| 307 | int userauth_hostbased(Authctxt *); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 308 | |
| 309 | #ifdef GSSAPI |
| 310 | int userauth_gssapi(Authctxt *authctxt); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 311 | int input_gssapi_response(int type, u_int32_t, void *); |
| 312 | int input_gssapi_token(int type, u_int32_t, void *); |
| 313 | int input_gssapi_hash(int type, u_int32_t, void *); |
| 314 | int input_gssapi_error(int, u_int32_t, void *); |
| 315 | int input_gssapi_errtok(int, u_int32_t, void *); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 316 | #endif |
| 317 | |
| 318 | void userauth(Authctxt *, char *); |
| 319 | |
| 320 | static int sign_and_send_pubkey(Authctxt *, Identity *); |
| 321 | static void pubkey_prepare(Authctxt *); |
| 322 | static void pubkey_cleanup(Authctxt *); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 323 | static Key *load_identity_file(char *, int); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 324 | |
| 325 | static Authmethod *authmethod_get(char *authlist); |
| 326 | static Authmethod *authmethod_lookup(const char *name); |
| 327 | static char *authmethods_get(void); |
| 328 | |
| 329 | Authmethod authmethods[] = { |
| 330 | #ifdef GSSAPI |
| 331 | {"gssapi-with-mic", |
| 332 | userauth_gssapi, |
| 333 | NULL, |
| 334 | &options.gss_authentication, |
| 335 | NULL}, |
| 336 | #endif |
| 337 | {"hostbased", |
| 338 | userauth_hostbased, |
| 339 | NULL, |
| 340 | &options.hostbased_authentication, |
| 341 | NULL}, |
| 342 | {"publickey", |
| 343 | userauth_pubkey, |
| 344 | NULL, |
| 345 | &options.pubkey_authentication, |
| 346 | NULL}, |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 347 | {"keyboard-interactive", |
| 348 | userauth_kbdint, |
| 349 | NULL, |
| 350 | &options.kbd_interactive_authentication, |
| 351 | &options.batch_mode}, |
| 352 | {"password", |
| 353 | userauth_passwd, |
| 354 | NULL, |
| 355 | &options.password_authentication, |
| 356 | &options.batch_mode}, |
| 357 | {"none", |
| 358 | userauth_none, |
| 359 | NULL, |
| 360 | NULL, |
| 361 | NULL}, |
| 362 | {NULL, NULL, NULL, NULL, NULL} |
| 363 | }; |
| 364 | |
| 365 | void |
| 366 | ssh_userauth2(const char *local_user, const char *server_user, char *host, |
| 367 | Sensitive *sensitive) |
| 368 | { |
| 369 | Authctxt authctxt; |
| 370 | int type; |
| 371 | |
| 372 | if (options.challenge_response_authentication) |
| 373 | options.kbd_interactive_authentication = 1; |
| 374 | |
| 375 | packet_start(SSH2_MSG_SERVICE_REQUEST); |
| 376 | packet_put_cstring("ssh-userauth"); |
| 377 | packet_send(); |
| 378 | debug("SSH2_MSG_SERVICE_REQUEST sent"); |
| 379 | packet_write_wait(); |
| 380 | type = packet_read(); |
| 381 | if (type != SSH2_MSG_SERVICE_ACCEPT) |
| 382 | fatal("Server denied authentication request: %d", type); |
| 383 | if (packet_remaining() > 0) { |
| 384 | char *reply = packet_get_string(NULL); |
| 385 | debug2("service_accept: %s", reply); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 386 | free(reply); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 387 | } else { |
| 388 | debug2("buggy server: service_accept w/o service"); |
| 389 | } |
| 390 | packet_check_eom(); |
| 391 | debug("SSH2_MSG_SERVICE_ACCEPT received"); |
| 392 | |
| 393 | if (options.preferred_authentications == NULL) |
| 394 | options.preferred_authentications = authmethods_get(); |
| 395 | |
| 396 | /* setup authentication context */ |
| 397 | memset(&authctxt, 0, sizeof(authctxt)); |
| 398 | pubkey_prepare(&authctxt); |
| 399 | authctxt.server_user = server_user; |
| 400 | authctxt.local_user = local_user; |
| 401 | authctxt.host = host; |
| 402 | authctxt.service = "ssh-connection"; /* service name */ |
| 403 | authctxt.success = 0; |
| 404 | authctxt.method = authmethod_lookup("none"); |
| 405 | authctxt.authlist = NULL; |
| 406 | authctxt.methoddata = NULL; |
| 407 | authctxt.sensitive = sensitive; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 408 | authctxt.active_ktype = authctxt.oktypes = authctxt.ktypes = NULL; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 409 | authctxt.info_req_seen = 0; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 410 | authctxt.agent_fd = -1; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 411 | if (authctxt.method == NULL) |
| 412 | fatal("ssh_userauth2: internal error: cannot send userauth none request"); |
| 413 | |
| 414 | /* initial userauth request */ |
| 415 | userauth_none(&authctxt); |
| 416 | |
| 417 | dispatch_init(&input_userauth_error); |
| 418 | dispatch_set(SSH2_MSG_USERAUTH_SUCCESS, &input_userauth_success); |
| 419 | dispatch_set(SSH2_MSG_USERAUTH_FAILURE, &input_userauth_failure); |
| 420 | dispatch_set(SSH2_MSG_USERAUTH_BANNER, &input_userauth_banner); |
| 421 | dispatch_run(DISPATCH_BLOCK, &authctxt.success, &authctxt); /* loop until success */ |
| 422 | |
| 423 | pubkey_cleanup(&authctxt); |
| 424 | dispatch_range(SSH2_MSG_USERAUTH_MIN, SSH2_MSG_USERAUTH_MAX, NULL); |
| 425 | |
| 426 | debug("Authentication succeeded (%s).", authctxt.method->name); |
| 427 | } |
| 428 | |
| 429 | void |
| 430 | userauth(Authctxt *authctxt, char *authlist) |
| 431 | { |
| 432 | if (authctxt->method != NULL && authctxt->method->cleanup != NULL) |
| 433 | authctxt->method->cleanup(authctxt); |
| 434 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 435 | free(authctxt->methoddata); |
| 436 | authctxt->methoddata = NULL; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 437 | if (authlist == NULL) { |
| 438 | authlist = authctxt->authlist; |
| 439 | } else { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 440 | free(authctxt->authlist); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 441 | authctxt->authlist = authlist; |
| 442 | } |
| 443 | for (;;) { |
| 444 | Authmethod *method = authmethod_get(authlist); |
| 445 | if (method == NULL) |
| 446 | fatal("Permission denied (%s).", authlist); |
| 447 | authctxt->method = method; |
| 448 | |
| 449 | /* reset the per method handler */ |
| 450 | dispatch_range(SSH2_MSG_USERAUTH_PER_METHOD_MIN, |
| 451 | SSH2_MSG_USERAUTH_PER_METHOD_MAX, NULL); |
| 452 | |
| 453 | /* and try new method */ |
| 454 | if (method->userauth(authctxt) != 0) { |
| 455 | debug2("we sent a %s packet, wait for reply", method->name); |
| 456 | break; |
| 457 | } else { |
| 458 | debug2("we did not send a packet, disable method"); |
| 459 | method->enabled = NULL; |
| 460 | } |
| 461 | } |
| 462 | } |
| 463 | |
| 464 | /* ARGSUSED */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 465 | int |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 466 | input_userauth_error(int type, u_int32_t seq, void *ctxt) |
| 467 | { |
| 468 | fatal("input_userauth_error: bad message during authentication: " |
| 469 | "type %d", type); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 470 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 471 | } |
| 472 | |
| 473 | /* ARGSUSED */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 474 | int |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 475 | input_userauth_banner(int type, u_int32_t seq, void *ctxt) |
| 476 | { |
| 477 | char *msg, *raw, *lang; |
| 478 | u_int len; |
| 479 | |
| 480 | debug3("input_userauth_banner"); |
| 481 | raw = packet_get_string(&len); |
| 482 | lang = packet_get_string(NULL); |
| 483 | if (len > 0 && options.log_level >= SYSLOG_LEVEL_INFO) { |
| 484 | if (len > 65536) |
| 485 | len = 65536; |
| 486 | msg = xmalloc(len * 4 + 1); /* max expansion from strnvis() */ |
| 487 | strnvis(msg, raw, len * 4 + 1, VIS_SAFE|VIS_OCTAL|VIS_NOSLASH); |
| 488 | fprintf(stderr, "%s", msg); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 489 | free(msg); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 490 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 491 | free(raw); |
| 492 | free(lang); |
| 493 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 494 | } |
| 495 | |
| 496 | /* ARGSUSED */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 497 | int |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 498 | input_userauth_success(int type, u_int32_t seq, void *ctxt) |
| 499 | { |
| 500 | Authctxt *authctxt = ctxt; |
| 501 | |
| 502 | if (authctxt == NULL) |
| 503 | fatal("input_userauth_success: no authentication context"); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 504 | free(authctxt->authlist); |
| 505 | authctxt->authlist = NULL; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 506 | if (authctxt->method != NULL && authctxt->method->cleanup != NULL) |
| 507 | authctxt->method->cleanup(authctxt); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 508 | free(authctxt->methoddata); |
| 509 | authctxt->methoddata = NULL; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 510 | authctxt->success = 1; /* break out */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 511 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 512 | } |
| 513 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 514 | int |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 515 | input_userauth_success_unexpected(int type, u_int32_t seq, void *ctxt) |
| 516 | { |
| 517 | Authctxt *authctxt = ctxt; |
| 518 | |
| 519 | if (authctxt == NULL) |
| 520 | fatal("%s: no authentication context", __func__); |
| 521 | |
| 522 | fatal("Unexpected authentication success during %s.", |
| 523 | authctxt->method->name); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 524 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 525 | } |
| 526 | |
| 527 | /* ARGSUSED */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 528 | int |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 529 | input_userauth_failure(int type, u_int32_t seq, void *ctxt) |
| 530 | { |
| 531 | Authctxt *authctxt = ctxt; |
| 532 | char *authlist = NULL; |
| 533 | int partial; |
| 534 | |
| 535 | if (authctxt == NULL) |
| 536 | fatal("input_userauth_failure: no authentication context"); |
| 537 | |
| 538 | authlist = packet_get_string(NULL); |
| 539 | partial = packet_get_char(); |
| 540 | packet_check_eom(); |
| 541 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 542 | if (partial != 0) { |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 543 | logit("Authenticated with partial success."); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 544 | /* reset state */ |
| 545 | pubkey_cleanup(authctxt); |
| 546 | pubkey_prepare(authctxt); |
| 547 | } |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 548 | debug("Authentications that can continue: %s", authlist); |
| 549 | |
| 550 | userauth(authctxt, authlist); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 551 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 552 | } |
| 553 | |
| 554 | /* ARGSUSED */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 555 | int |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 556 | input_userauth_pk_ok(int type, u_int32_t seq, void *ctxt) |
| 557 | { |
| 558 | Authctxt *authctxt = ctxt; |
| 559 | Key *key = NULL; |
| 560 | Identity *id = NULL; |
| 561 | Buffer b; |
| 562 | int pktype, sent = 0; |
| 563 | u_int alen, blen; |
| 564 | char *pkalg, *fp; |
| 565 | u_char *pkblob; |
| 566 | |
| 567 | if (authctxt == NULL) |
| 568 | fatal("input_userauth_pk_ok: no authentication context"); |
| 569 | if (datafellows & SSH_BUG_PKOK) { |
| 570 | /* this is similar to SSH_BUG_PKAUTH */ |
| 571 | debug2("input_userauth_pk_ok: SSH_BUG_PKOK"); |
| 572 | pkblob = packet_get_string(&blen); |
| 573 | buffer_init(&b); |
| 574 | buffer_append(&b, pkblob, blen); |
| 575 | pkalg = buffer_get_string(&b, &alen); |
| 576 | buffer_free(&b); |
| 577 | } else { |
| 578 | pkalg = packet_get_string(&alen); |
| 579 | pkblob = packet_get_string(&blen); |
| 580 | } |
| 581 | packet_check_eom(); |
| 582 | |
| 583 | debug("Server accepts key: pkalg %s blen %u", pkalg, blen); |
| 584 | |
| 585 | if ((pktype = key_type_from_name(pkalg)) == KEY_UNSPEC) { |
| 586 | debug("unknown pkalg %s", pkalg); |
| 587 | goto done; |
| 588 | } |
| 589 | if ((key = key_from_blob(pkblob, blen)) == NULL) { |
| 590 | debug("no key from blob. pkalg %s", pkalg); |
| 591 | goto done; |
| 592 | } |
| 593 | if (key->type != pktype) { |
| 594 | error("input_userauth_pk_ok: type mismatch " |
| 595 | "for decoded key (received %d, expected %d)", |
| 596 | key->type, pktype); |
| 597 | goto done; |
| 598 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 599 | if ((fp = sshkey_fingerprint(key, options.fingerprint_hash, |
| 600 | SSH_FP_DEFAULT)) == NULL) |
| 601 | goto done; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 602 | debug2("input_userauth_pk_ok: fp %s", fp); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 603 | free(fp); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 604 | |
| 605 | /* |
| 606 | * search keys in the reverse order, because last candidate has been |
| 607 | * moved to the end of the queue. this also avoids confusion by |
| 608 | * duplicate keys |
| 609 | */ |
| 610 | TAILQ_FOREACH_REVERSE(id, &authctxt->keys, idlist, next) { |
| 611 | if (key_equal(key, id->key)) { |
| 612 | sent = sign_and_send_pubkey(authctxt, id); |
| 613 | break; |
| 614 | } |
| 615 | } |
| 616 | done: |
| 617 | if (key != NULL) |
| 618 | key_free(key); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 619 | free(pkalg); |
| 620 | free(pkblob); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 621 | |
| 622 | /* try another method if we did not send a packet */ |
| 623 | if (sent == 0) |
| 624 | userauth(authctxt, NULL); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 625 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 626 | } |
| 627 | |
| 628 | #ifdef GSSAPI |
| 629 | int |
| 630 | userauth_gssapi(Authctxt *authctxt) |
| 631 | { |
| 632 | Gssctxt *gssctxt = NULL; |
| 633 | static gss_OID_set gss_supported = NULL; |
| 634 | static u_int mech = 0; |
| 635 | OM_uint32 min; |
| 636 | int ok = 0; |
| 637 | |
| 638 | /* Try one GSSAPI method at a time, rather than sending them all at |
| 639 | * once. */ |
| 640 | |
| 641 | if (gss_supported == NULL) |
| 642 | gss_indicate_mechs(&min, &gss_supported); |
| 643 | |
| 644 | /* Check to see if the mechanism is usable before we offer it */ |
| 645 | while (mech < gss_supported->count && !ok) { |
| 646 | /* My DER encoding requires length<128 */ |
| 647 | if (gss_supported->elements[mech].length < 128 && |
| 648 | ssh_gssapi_check_mechanism(&gssctxt, |
| 649 | &gss_supported->elements[mech], authctxt->host)) { |
| 650 | ok = 1; /* Mechanism works */ |
| 651 | } else { |
| 652 | mech++; |
| 653 | } |
| 654 | } |
| 655 | |
| 656 | if (!ok) |
| 657 | return 0; |
| 658 | |
| 659 | authctxt->methoddata=(void *)gssctxt; |
| 660 | |
| 661 | packet_start(SSH2_MSG_USERAUTH_REQUEST); |
| 662 | packet_put_cstring(authctxt->server_user); |
| 663 | packet_put_cstring(authctxt->service); |
| 664 | packet_put_cstring(authctxt->method->name); |
| 665 | |
| 666 | packet_put_int(1); |
| 667 | |
| 668 | packet_put_int((gss_supported->elements[mech].length) + 2); |
| 669 | packet_put_char(SSH_GSS_OIDTYPE); |
| 670 | packet_put_char(gss_supported->elements[mech].length); |
| 671 | packet_put_raw(gss_supported->elements[mech].elements, |
| 672 | gss_supported->elements[mech].length); |
| 673 | |
| 674 | packet_send(); |
| 675 | |
| 676 | dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_RESPONSE, &input_gssapi_response); |
| 677 | dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, &input_gssapi_token); |
| 678 | dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERROR, &input_gssapi_error); |
| 679 | dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK, &input_gssapi_errtok); |
| 680 | |
| 681 | mech++; /* Move along to next candidate */ |
| 682 | |
| 683 | return 1; |
| 684 | } |
| 685 | |
| 686 | static OM_uint32 |
| 687 | process_gssapi_token(void *ctxt, gss_buffer_t recv_tok) |
| 688 | { |
| 689 | Authctxt *authctxt = ctxt; |
| 690 | Gssctxt *gssctxt = authctxt->methoddata; |
| 691 | gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER; |
| 692 | gss_buffer_desc mic = GSS_C_EMPTY_BUFFER; |
| 693 | gss_buffer_desc gssbuf; |
| 694 | OM_uint32 status, ms, flags; |
| 695 | Buffer b; |
| 696 | |
| 697 | status = ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds, |
| 698 | recv_tok, &send_tok, &flags); |
| 699 | |
| 700 | if (send_tok.length > 0) { |
| 701 | if (GSS_ERROR(status)) |
| 702 | packet_start(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK); |
| 703 | else |
| 704 | packet_start(SSH2_MSG_USERAUTH_GSSAPI_TOKEN); |
| 705 | |
| 706 | packet_put_string(send_tok.value, send_tok.length); |
| 707 | packet_send(); |
| 708 | gss_release_buffer(&ms, &send_tok); |
| 709 | } |
| 710 | |
| 711 | if (status == GSS_S_COMPLETE) { |
| 712 | /* send either complete or MIC, depending on mechanism */ |
| 713 | if (!(flags & GSS_C_INTEG_FLAG)) { |
| 714 | packet_start(SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE); |
| 715 | packet_send(); |
| 716 | } else { |
| 717 | ssh_gssapi_buildmic(&b, authctxt->server_user, |
| 718 | authctxt->service, "gssapi-with-mic"); |
| 719 | |
| 720 | gssbuf.value = buffer_ptr(&b); |
| 721 | gssbuf.length = buffer_len(&b); |
| 722 | |
| 723 | status = ssh_gssapi_sign(gssctxt, &gssbuf, &mic); |
| 724 | |
| 725 | if (!GSS_ERROR(status)) { |
| 726 | packet_start(SSH2_MSG_USERAUTH_GSSAPI_MIC); |
| 727 | packet_put_string(mic.value, mic.length); |
| 728 | |
| 729 | packet_send(); |
| 730 | } |
| 731 | |
| 732 | buffer_free(&b); |
| 733 | gss_release_buffer(&ms, &mic); |
| 734 | } |
| 735 | } |
| 736 | |
| 737 | return status; |
| 738 | } |
| 739 | |
| 740 | /* ARGSUSED */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 741 | int |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 742 | input_gssapi_response(int type, u_int32_t plen, void *ctxt) |
| 743 | { |
| 744 | Authctxt *authctxt = ctxt; |
| 745 | Gssctxt *gssctxt; |
| 746 | int oidlen; |
| 747 | char *oidv; |
| 748 | |
| 749 | if (authctxt == NULL) |
| 750 | fatal("input_gssapi_response: no authentication context"); |
| 751 | gssctxt = authctxt->methoddata; |
| 752 | |
| 753 | /* Setup our OID */ |
| 754 | oidv = packet_get_string(&oidlen); |
| 755 | |
| 756 | if (oidlen <= 2 || |
| 757 | oidv[0] != SSH_GSS_OIDTYPE || |
| 758 | oidv[1] != oidlen - 2) { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 759 | free(oidv); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 760 | debug("Badly encoded mechanism OID received"); |
| 761 | userauth(authctxt, NULL); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 762 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 763 | } |
| 764 | |
| 765 | if (!ssh_gssapi_check_oid(gssctxt, oidv + 2, oidlen - 2)) |
| 766 | fatal("Server returned different OID than expected"); |
| 767 | |
| 768 | packet_check_eom(); |
| 769 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 770 | free(oidv); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 771 | |
| 772 | if (GSS_ERROR(process_gssapi_token(ctxt, GSS_C_NO_BUFFER))) { |
| 773 | /* Start again with next method on list */ |
| 774 | debug("Trying to start again"); |
| 775 | userauth(authctxt, NULL); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 776 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 777 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 778 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 779 | } |
| 780 | |
| 781 | /* ARGSUSED */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 782 | int |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 783 | input_gssapi_token(int type, u_int32_t plen, void *ctxt) |
| 784 | { |
| 785 | Authctxt *authctxt = ctxt; |
| 786 | gss_buffer_desc recv_tok; |
| 787 | OM_uint32 status; |
| 788 | u_int slen; |
| 789 | |
| 790 | if (authctxt == NULL) |
| 791 | fatal("input_gssapi_response: no authentication context"); |
| 792 | |
| 793 | recv_tok.value = packet_get_string(&slen); |
| 794 | recv_tok.length = slen; /* safe typecast */ |
| 795 | |
| 796 | packet_check_eom(); |
| 797 | |
| 798 | status = process_gssapi_token(ctxt, &recv_tok); |
| 799 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 800 | free(recv_tok.value); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 801 | |
| 802 | if (GSS_ERROR(status)) { |
| 803 | /* Start again with the next method in the list */ |
| 804 | userauth(authctxt, NULL); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 805 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 806 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 807 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 808 | } |
| 809 | |
| 810 | /* ARGSUSED */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 811 | int |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 812 | input_gssapi_errtok(int type, u_int32_t plen, void *ctxt) |
| 813 | { |
| 814 | Authctxt *authctxt = ctxt; |
| 815 | Gssctxt *gssctxt; |
| 816 | gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER; |
| 817 | gss_buffer_desc recv_tok; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 818 | OM_uint32 ms; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 819 | u_int len; |
| 820 | |
| 821 | if (authctxt == NULL) |
| 822 | fatal("input_gssapi_response: no authentication context"); |
| 823 | gssctxt = authctxt->methoddata; |
| 824 | |
| 825 | recv_tok.value = packet_get_string(&len); |
| 826 | recv_tok.length = len; |
| 827 | |
| 828 | packet_check_eom(); |
| 829 | |
| 830 | /* Stick it into GSSAPI and see what it says */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 831 | (void)ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds, |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 832 | &recv_tok, &send_tok, NULL); |
| 833 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 834 | free(recv_tok.value); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 835 | gss_release_buffer(&ms, &send_tok); |
| 836 | |
| 837 | /* Server will be returning a failed packet after this one */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 838 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 839 | } |
| 840 | |
| 841 | /* ARGSUSED */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 842 | int |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 843 | input_gssapi_error(int type, u_int32_t plen, void *ctxt) |
| 844 | { |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 845 | char *msg; |
| 846 | char *lang; |
| 847 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 848 | /* maj */(void)packet_get_int(); |
| 849 | /* min */(void)packet_get_int(); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 850 | msg=packet_get_string(NULL); |
| 851 | lang=packet_get_string(NULL); |
| 852 | |
| 853 | packet_check_eom(); |
| 854 | |
| 855 | debug("Server GSSAPI Error:\n%s", msg); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 856 | free(msg); |
| 857 | free(lang); |
| 858 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 859 | } |
| 860 | #endif /* GSSAPI */ |
| 861 | |
| 862 | int |
| 863 | userauth_none(Authctxt *authctxt) |
| 864 | { |
| 865 | /* initial userauth request */ |
| 866 | packet_start(SSH2_MSG_USERAUTH_REQUEST); |
| 867 | packet_put_cstring(authctxt->server_user); |
| 868 | packet_put_cstring(authctxt->service); |
| 869 | packet_put_cstring(authctxt->method->name); |
| 870 | packet_send(); |
| 871 | return 1; |
| 872 | } |
| 873 | |
| 874 | int |
| 875 | userauth_passwd(Authctxt *authctxt) |
| 876 | { |
| 877 | static int attempt = 0; |
| 878 | char prompt[150]; |
| 879 | char *password; |
| 880 | const char *host = options.host_key_alias ? options.host_key_alias : |
| 881 | authctxt->host; |
| 882 | |
| 883 | if (attempt++ >= options.number_of_password_prompts) |
| 884 | return 0; |
| 885 | |
| 886 | if (attempt != 1) |
| 887 | error("Permission denied, please try again."); |
| 888 | |
| 889 | snprintf(prompt, sizeof(prompt), "%.30s@%.128s's password: ", |
| 890 | authctxt->server_user, host); |
| 891 | password = read_passphrase(prompt, 0); |
| 892 | packet_start(SSH2_MSG_USERAUTH_REQUEST); |
| 893 | packet_put_cstring(authctxt->server_user); |
| 894 | packet_put_cstring(authctxt->service); |
| 895 | packet_put_cstring(authctxt->method->name); |
| 896 | packet_put_char(0); |
| 897 | packet_put_cstring(password); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 898 | explicit_bzero(password, strlen(password)); |
| 899 | free(password); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 900 | packet_add_padding(64); |
| 901 | packet_send(); |
| 902 | |
| 903 | dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ, |
| 904 | &input_userauth_passwd_changereq); |
| 905 | |
| 906 | return 1; |
| 907 | } |
| 908 | |
| 909 | /* |
| 910 | * parse PASSWD_CHANGEREQ, prompt user and send SSH2_MSG_USERAUTH_REQUEST |
| 911 | */ |
| 912 | /* ARGSUSED */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 913 | int |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 914 | input_userauth_passwd_changereq(int type, u_int32_t seqnr, void *ctxt) |
| 915 | { |
| 916 | Authctxt *authctxt = ctxt; |
| 917 | char *info, *lang, *password = NULL, *retype = NULL; |
| 918 | char prompt[150]; |
| 919 | const char *host = options.host_key_alias ? options.host_key_alias : |
| 920 | authctxt->host; |
| 921 | |
| 922 | debug2("input_userauth_passwd_changereq"); |
| 923 | |
| 924 | if (authctxt == NULL) |
| 925 | fatal("input_userauth_passwd_changereq: " |
| 926 | "no authentication context"); |
| 927 | |
| 928 | info = packet_get_string(NULL); |
| 929 | lang = packet_get_string(NULL); |
| 930 | if (strlen(info) > 0) |
| 931 | logit("%s", info); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 932 | free(info); |
| 933 | free(lang); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 934 | packet_start(SSH2_MSG_USERAUTH_REQUEST); |
| 935 | packet_put_cstring(authctxt->server_user); |
| 936 | packet_put_cstring(authctxt->service); |
| 937 | packet_put_cstring(authctxt->method->name); |
| 938 | packet_put_char(1); /* additional info */ |
| 939 | snprintf(prompt, sizeof(prompt), |
| 940 | "Enter %.30s@%.128s's old password: ", |
| 941 | authctxt->server_user, host); |
| 942 | password = read_passphrase(prompt, 0); |
| 943 | packet_put_cstring(password); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 944 | explicit_bzero(password, strlen(password)); |
| 945 | free(password); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 946 | password = NULL; |
| 947 | while (password == NULL) { |
| 948 | snprintf(prompt, sizeof(prompt), |
| 949 | "Enter %.30s@%.128s's new password: ", |
| 950 | authctxt->server_user, host); |
| 951 | password = read_passphrase(prompt, RP_ALLOW_EOF); |
| 952 | if (password == NULL) { |
| 953 | /* bail out */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 954 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 955 | } |
| 956 | snprintf(prompt, sizeof(prompt), |
| 957 | "Retype %.30s@%.128s's new password: ", |
| 958 | authctxt->server_user, host); |
| 959 | retype = read_passphrase(prompt, 0); |
| 960 | if (strcmp(password, retype) != 0) { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 961 | explicit_bzero(password, strlen(password)); |
| 962 | free(password); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 963 | logit("Mismatch; try again, EOF to quit."); |
| 964 | password = NULL; |
| 965 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 966 | explicit_bzero(retype, strlen(retype)); |
| 967 | free(retype); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 968 | } |
| 969 | packet_put_cstring(password); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 970 | explicit_bzero(password, strlen(password)); |
| 971 | free(password); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 972 | packet_add_padding(64); |
| 973 | packet_send(); |
| 974 | |
| 975 | dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ, |
| 976 | &input_userauth_passwd_changereq); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 977 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 978 | } |
| 979 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 980 | static int |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 981 | identity_sign(struct identity *id, u_char **sigp, size_t *lenp, |
| 982 | const u_char *data, size_t datalen, u_int compat) |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 983 | { |
| 984 | Key *prv; |
| 985 | int ret; |
| 986 | |
| 987 | /* the agent supports this key */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 988 | if (id->agent_fd) |
| 989 | return ssh_agent_sign(id->agent_fd, id->key, sigp, lenp, |
| 990 | data, datalen, compat); |
| 991 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 992 | /* |
| 993 | * we have already loaded the private key or |
| 994 | * the private key is stored in external hardware |
| 995 | */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 996 | if (id->isprivate || (id->key->flags & SSHKEY_FLAG_EXT)) |
| 997 | return (sshkey_sign(id->key, sigp, lenp, data, datalen, |
| 998 | compat)); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 999 | /* load the private key from the file */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1000 | if ((prv = load_identity_file(id->filename, id->userprovided)) == NULL) |
| 1001 | return (-1); /* XXX return decent error code */ |
| 1002 | ret = sshkey_sign(prv, sigp, lenp, data, datalen, compat); |
| 1003 | sshkey_free(prv); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1004 | return (ret); |
| 1005 | } |
| 1006 | |
| 1007 | static int |
| 1008 | sign_and_send_pubkey(Authctxt *authctxt, Identity *id) |
| 1009 | { |
| 1010 | Buffer b; |
| 1011 | u_char *blob, *signature; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1012 | u_int bloblen; |
| 1013 | size_t slen; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1014 | u_int skip = 0; |
| 1015 | int ret = -1; |
| 1016 | int have_sig = 1; |
| 1017 | char *fp; |
| 1018 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1019 | if ((fp = sshkey_fingerprint(id->key, options.fingerprint_hash, |
| 1020 | SSH_FP_DEFAULT)) == NULL) |
| 1021 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1022 | debug3("sign_and_send_pubkey: %s %s", key_type(id->key), fp); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1023 | free(fp); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1024 | |
| 1025 | if (key_to_blob(id->key, &blob, &bloblen) == 0) { |
| 1026 | /* we cannot handle this key */ |
| 1027 | debug3("sign_and_send_pubkey: cannot handle key"); |
| 1028 | return 0; |
| 1029 | } |
| 1030 | /* data to be signed */ |
| 1031 | buffer_init(&b); |
| 1032 | if (datafellows & SSH_OLD_SESSIONID) { |
| 1033 | buffer_append(&b, session_id2, session_id2_len); |
| 1034 | skip = session_id2_len; |
| 1035 | } else { |
| 1036 | buffer_put_string(&b, session_id2, session_id2_len); |
| 1037 | skip = buffer_len(&b); |
| 1038 | } |
| 1039 | buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST); |
| 1040 | buffer_put_cstring(&b, authctxt->server_user); |
| 1041 | buffer_put_cstring(&b, |
| 1042 | datafellows & SSH_BUG_PKSERVICE ? |
| 1043 | "ssh-userauth" : |
| 1044 | authctxt->service); |
| 1045 | if (datafellows & SSH_BUG_PKAUTH) { |
| 1046 | buffer_put_char(&b, have_sig); |
| 1047 | } else { |
| 1048 | buffer_put_cstring(&b, authctxt->method->name); |
| 1049 | buffer_put_char(&b, have_sig); |
| 1050 | buffer_put_cstring(&b, key_ssh_name(id->key)); |
| 1051 | } |
| 1052 | buffer_put_string(&b, blob, bloblen); |
| 1053 | |
| 1054 | /* generate signature */ |
| 1055 | ret = identity_sign(id, &signature, &slen, |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1056 | buffer_ptr(&b), buffer_len(&b), datafellows); |
| 1057 | if (ret != 0) { |
| 1058 | free(blob); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1059 | buffer_free(&b); |
| 1060 | return 0; |
| 1061 | } |
| 1062 | #ifdef DEBUG_PK |
| 1063 | buffer_dump(&b); |
| 1064 | #endif |
| 1065 | if (datafellows & SSH_BUG_PKSERVICE) { |
| 1066 | buffer_clear(&b); |
| 1067 | buffer_append(&b, session_id2, session_id2_len); |
| 1068 | skip = session_id2_len; |
| 1069 | buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST); |
| 1070 | buffer_put_cstring(&b, authctxt->server_user); |
| 1071 | buffer_put_cstring(&b, authctxt->service); |
| 1072 | buffer_put_cstring(&b, authctxt->method->name); |
| 1073 | buffer_put_char(&b, have_sig); |
| 1074 | if (!(datafellows & SSH_BUG_PKAUTH)) |
| 1075 | buffer_put_cstring(&b, key_ssh_name(id->key)); |
| 1076 | buffer_put_string(&b, blob, bloblen); |
| 1077 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1078 | free(blob); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1079 | |
| 1080 | /* append signature */ |
| 1081 | buffer_put_string(&b, signature, slen); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1082 | free(signature); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1083 | |
| 1084 | /* skip session id and packet type */ |
| 1085 | if (buffer_len(&b) < skip + 1) |
| 1086 | fatal("userauth_pubkey: internal error"); |
| 1087 | buffer_consume(&b, skip + 1); |
| 1088 | |
| 1089 | /* put remaining data from buffer into packet */ |
| 1090 | packet_start(SSH2_MSG_USERAUTH_REQUEST); |
| 1091 | packet_put_raw(buffer_ptr(&b), buffer_len(&b)); |
| 1092 | buffer_free(&b); |
| 1093 | packet_send(); |
| 1094 | |
| 1095 | return 1; |
| 1096 | } |
| 1097 | |
| 1098 | static int |
| 1099 | send_pubkey_test(Authctxt *authctxt, Identity *id) |
| 1100 | { |
| 1101 | u_char *blob; |
| 1102 | u_int bloblen, have_sig = 0; |
| 1103 | |
| 1104 | debug3("send_pubkey_test"); |
| 1105 | |
| 1106 | if (key_to_blob(id->key, &blob, &bloblen) == 0) { |
| 1107 | /* we cannot handle this key */ |
| 1108 | debug3("send_pubkey_test: cannot handle key"); |
| 1109 | return 0; |
| 1110 | } |
| 1111 | /* register callback for USERAUTH_PK_OK message */ |
| 1112 | dispatch_set(SSH2_MSG_USERAUTH_PK_OK, &input_userauth_pk_ok); |
| 1113 | |
| 1114 | packet_start(SSH2_MSG_USERAUTH_REQUEST); |
| 1115 | packet_put_cstring(authctxt->server_user); |
| 1116 | packet_put_cstring(authctxt->service); |
| 1117 | packet_put_cstring(authctxt->method->name); |
| 1118 | packet_put_char(have_sig); |
| 1119 | if (!(datafellows & SSH_BUG_PKAUTH)) |
| 1120 | packet_put_cstring(key_ssh_name(id->key)); |
| 1121 | packet_put_string(blob, bloblen); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1122 | free(blob); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1123 | packet_send(); |
| 1124 | return 1; |
| 1125 | } |
| 1126 | |
| 1127 | static Key * |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1128 | load_identity_file(char *filename, int userprovided) |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1129 | { |
| 1130 | Key *private; |
| 1131 | char prompt[300], *passphrase; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1132 | int r, perm_ok = 0, quit = 0, i; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1133 | struct stat st; |
| 1134 | |
| 1135 | if (stat(filename, &st) < 0) { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1136 | (userprovided ? logit : debug3)("no such identity: %s: %s", |
| 1137 | filename, strerror(errno)); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1138 | return NULL; |
| 1139 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1140 | snprintf(prompt, sizeof prompt, |
| 1141 | "Enter passphrase for key '%.100s': ", filename); |
| 1142 | for (i = 0; i <= options.number_of_password_prompts; i++) { |
| 1143 | if (i == 0) |
| 1144 | passphrase = ""; |
| 1145 | else { |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1146 | passphrase = read_passphrase(prompt, 0); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1147 | if (*passphrase == '\0') { |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1148 | debug2("no passphrase given, try next key"); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1149 | free(passphrase); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1150 | break; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1151 | } |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1152 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1153 | switch ((r = sshkey_load_private_type(KEY_UNSPEC, filename, |
| 1154 | passphrase, &private, NULL, &perm_ok))) { |
| 1155 | case 0: |
| 1156 | break; |
| 1157 | case SSH_ERR_KEY_WRONG_PASSPHRASE: |
| 1158 | if (options.batch_mode) { |
| 1159 | quit = 1; |
| 1160 | break; |
| 1161 | } |
| 1162 | if (i != 0) |
| 1163 | debug2("bad passphrase given, try again..."); |
| 1164 | break; |
| 1165 | case SSH_ERR_SYSTEM_ERROR: |
| 1166 | if (errno == ENOENT) { |
| 1167 | debug2("Load key \"%s\": %s", |
| 1168 | filename, ssh_err(r)); |
| 1169 | quit = 1; |
| 1170 | break; |
| 1171 | } |
| 1172 | /* FALLTHROUGH */ |
| 1173 | default: |
| 1174 | error("Load key \"%s\": %s", filename, ssh_err(r)); |
| 1175 | quit = 1; |
| 1176 | break; |
| 1177 | } |
| 1178 | if (i > 0) { |
| 1179 | explicit_bzero(passphrase, strlen(passphrase)); |
| 1180 | free(passphrase); |
| 1181 | } |
| 1182 | if (private != NULL || quit) |
| 1183 | break; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1184 | } |
| 1185 | return private; |
| 1186 | } |
| 1187 | |
| 1188 | /* |
| 1189 | * try keys in the following order: |
| 1190 | * 1. agent keys that are found in the config file |
| 1191 | * 2. other agent keys |
| 1192 | * 3. keys that are only listed in the config file |
| 1193 | */ |
| 1194 | static void |
| 1195 | pubkey_prepare(Authctxt *authctxt) |
| 1196 | { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1197 | struct identity *id, *id2, *tmp; |
| 1198 | struct idlist agent, files, *preferred; |
| 1199 | struct sshkey *key; |
| 1200 | int agent_fd, i, r, found; |
| 1201 | size_t j; |
| 1202 | struct ssh_identitylist *idlist; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1203 | |
| 1204 | TAILQ_INIT(&agent); /* keys from the agent */ |
| 1205 | TAILQ_INIT(&files); /* keys from the config file */ |
| 1206 | preferred = &authctxt->keys; |
| 1207 | TAILQ_INIT(preferred); /* preferred order of keys */ |
| 1208 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1209 | /* list of keys stored in the filesystem and PKCS#11 */ |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1210 | for (i = 0; i < options.num_identity_files; i++) { |
| 1211 | key = options.identity_keys[i]; |
| 1212 | if (key && key->type == KEY_RSA1) |
| 1213 | continue; |
| 1214 | if (key && key->cert && key->cert->type != SSH2_CERT_TYPE_USER) |
| 1215 | continue; |
| 1216 | options.identity_keys[i] = NULL; |
| 1217 | id = xcalloc(1, sizeof(*id)); |
| 1218 | id->key = key; |
| 1219 | id->filename = xstrdup(options.identity_files[i]); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1220 | id->userprovided = options.identity_file_userprovided[i]; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1221 | TAILQ_INSERT_TAIL(&files, id, next); |
| 1222 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1223 | /* Prefer PKCS11 keys that are explicitly listed */ |
| 1224 | TAILQ_FOREACH_SAFE(id, &files, next, tmp) { |
| 1225 | if (id->key == NULL || (id->key->flags & SSHKEY_FLAG_EXT) == 0) |
| 1226 | continue; |
| 1227 | found = 0; |
| 1228 | TAILQ_FOREACH(id2, &files, next) { |
| 1229 | if (id2->key == NULL || |
| 1230 | (id2->key->flags & SSHKEY_FLAG_EXT) == 0) |
| 1231 | continue; |
| 1232 | if (sshkey_equal(id->key, id2->key)) { |
| 1233 | TAILQ_REMOVE(&files, id, next); |
| 1234 | TAILQ_INSERT_TAIL(preferred, id, next); |
| 1235 | found = 1; |
| 1236 | break; |
| 1237 | } |
| 1238 | } |
| 1239 | /* If IdentitiesOnly set and key not found then don't use it */ |
| 1240 | if (!found && options.identities_only) { |
| 1241 | TAILQ_REMOVE(&files, id, next); |
| 1242 | explicit_bzero(id, sizeof(*id)); |
| 1243 | free(id); |
| 1244 | } |
| 1245 | } |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1246 | /* list of keys supported by the agent */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1247 | if ((r = ssh_get_authentication_socket(&agent_fd)) != 0) { |
| 1248 | if (r != SSH_ERR_AGENT_NOT_PRESENT) |
| 1249 | debug("%s: ssh_get_authentication_socket: %s", |
| 1250 | __func__, ssh_err(r)); |
| 1251 | } else if ((r = ssh_fetch_identitylist(agent_fd, 2, &idlist)) != 0) { |
| 1252 | if (r != SSH_ERR_AGENT_NO_IDENTITIES) |
| 1253 | debug("%s: ssh_fetch_identitylist: %s", |
| 1254 | __func__, ssh_err(r)); |
| 1255 | } else { |
| 1256 | for (j = 0; j < idlist->nkeys; j++) { |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1257 | found = 0; |
| 1258 | TAILQ_FOREACH(id, &files, next) { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1259 | /* |
| 1260 | * agent keys from the config file are |
| 1261 | * preferred |
| 1262 | */ |
| 1263 | if (sshkey_equal(idlist->keys[j], id->key)) { |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1264 | TAILQ_REMOVE(&files, id, next); |
| 1265 | TAILQ_INSERT_TAIL(preferred, id, next); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1266 | id->agent_fd = agent_fd; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1267 | found = 1; |
| 1268 | break; |
| 1269 | } |
| 1270 | } |
| 1271 | if (!found && !options.identities_only) { |
| 1272 | id = xcalloc(1, sizeof(*id)); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1273 | /* XXX "steals" key/comment from idlist */ |
| 1274 | id->key = idlist->keys[j]; |
| 1275 | id->filename = idlist->comments[j]; |
| 1276 | idlist->keys[j] = NULL; |
| 1277 | idlist->comments[j] = NULL; |
| 1278 | id->agent_fd = agent_fd; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1279 | TAILQ_INSERT_TAIL(&agent, id, next); |
| 1280 | } |
| 1281 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1282 | ssh_free_identitylist(idlist); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1283 | /* append remaining agent keys */ |
| 1284 | for (id = TAILQ_FIRST(&agent); id; id = TAILQ_FIRST(&agent)) { |
| 1285 | TAILQ_REMOVE(&agent, id, next); |
| 1286 | TAILQ_INSERT_TAIL(preferred, id, next); |
| 1287 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1288 | authctxt->agent_fd = agent_fd; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1289 | } |
| 1290 | /* append remaining keys from the config file */ |
| 1291 | for (id = TAILQ_FIRST(&files); id; id = TAILQ_FIRST(&files)) { |
| 1292 | TAILQ_REMOVE(&files, id, next); |
| 1293 | TAILQ_INSERT_TAIL(preferred, id, next); |
| 1294 | } |
| 1295 | TAILQ_FOREACH(id, preferred, next) { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1296 | debug2("key: %s (%p),%s", id->filename, id->key, |
| 1297 | id->userprovided ? " explicit" : ""); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1298 | } |
| 1299 | } |
| 1300 | |
| 1301 | static void |
| 1302 | pubkey_cleanup(Authctxt *authctxt) |
| 1303 | { |
| 1304 | Identity *id; |
| 1305 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1306 | if (authctxt->agent_fd != -1) |
| 1307 | ssh_close_authentication_socket(authctxt->agent_fd); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1308 | for (id = TAILQ_FIRST(&authctxt->keys); id; |
| 1309 | id = TAILQ_FIRST(&authctxt->keys)) { |
| 1310 | TAILQ_REMOVE(&authctxt->keys, id, next); |
| 1311 | if (id->key) |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1312 | sshkey_free(id->key); |
| 1313 | free(id->filename); |
| 1314 | free(id); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1315 | } |
| 1316 | } |
| 1317 | |
| 1318 | int |
| 1319 | userauth_pubkey(Authctxt *authctxt) |
| 1320 | { |
| 1321 | Identity *id; |
| 1322 | int sent = 0; |
| 1323 | |
| 1324 | while ((id = TAILQ_FIRST(&authctxt->keys))) { |
| 1325 | if (id->tried++) |
| 1326 | return (0); |
| 1327 | /* move key to the end of the queue */ |
| 1328 | TAILQ_REMOVE(&authctxt->keys, id, next); |
| 1329 | TAILQ_INSERT_TAIL(&authctxt->keys, id, next); |
| 1330 | /* |
| 1331 | * send a test message if we have the public key. for |
| 1332 | * encrypted keys we cannot do this and have to load the |
| 1333 | * private key instead |
| 1334 | */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1335 | if (id->key != NULL) { |
| 1336 | if (key_type_plain(id->key->type) == KEY_RSA && |
| 1337 | (datafellows & SSH_BUG_RSASIGMD5) != 0) { |
| 1338 | debug("Skipped %s key %s for RSA/MD5 server", |
| 1339 | key_type(id->key), id->filename); |
| 1340 | } else if (id->key->type != KEY_RSA1) { |
| 1341 | debug("Offering %s public key: %s", |
| 1342 | key_type(id->key), id->filename); |
| 1343 | sent = send_pubkey_test(authctxt, id); |
| 1344 | } |
| 1345 | } else { |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1346 | debug("Trying private key: %s", id->filename); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1347 | id->key = load_identity_file(id->filename, |
| 1348 | id->userprovided); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1349 | if (id->key != NULL) { |
| 1350 | id->isprivate = 1; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1351 | if (key_type_plain(id->key->type) == KEY_RSA && |
| 1352 | (datafellows & SSH_BUG_RSASIGMD5) != 0) { |
| 1353 | debug("Skipped %s key %s for RSA/MD5 " |
| 1354 | "server", key_type(id->key), |
| 1355 | id->filename); |
| 1356 | } else { |
| 1357 | sent = sign_and_send_pubkey( |
| 1358 | authctxt, id); |
| 1359 | } |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1360 | key_free(id->key); |
| 1361 | id->key = NULL; |
| 1362 | } |
| 1363 | } |
| 1364 | if (sent) |
| 1365 | return (sent); |
| 1366 | } |
| 1367 | return (0); |
| 1368 | } |
| 1369 | |
| 1370 | /* |
| 1371 | * Send userauth request message specifying keyboard-interactive method. |
| 1372 | */ |
| 1373 | int |
| 1374 | userauth_kbdint(Authctxt *authctxt) |
| 1375 | { |
| 1376 | static int attempt = 0; |
| 1377 | |
| 1378 | if (attempt++ >= options.number_of_password_prompts) |
| 1379 | return 0; |
| 1380 | /* disable if no SSH2_MSG_USERAUTH_INFO_REQUEST has been seen */ |
| 1381 | if (attempt > 1 && !authctxt->info_req_seen) { |
| 1382 | debug3("userauth_kbdint: disable: no info_req_seen"); |
| 1383 | dispatch_set(SSH2_MSG_USERAUTH_INFO_REQUEST, NULL); |
| 1384 | return 0; |
| 1385 | } |
| 1386 | |
| 1387 | debug2("userauth_kbdint"); |
| 1388 | packet_start(SSH2_MSG_USERAUTH_REQUEST); |
| 1389 | packet_put_cstring(authctxt->server_user); |
| 1390 | packet_put_cstring(authctxt->service); |
| 1391 | packet_put_cstring(authctxt->method->name); |
| 1392 | packet_put_cstring(""); /* lang */ |
| 1393 | packet_put_cstring(options.kbd_interactive_devices ? |
| 1394 | options.kbd_interactive_devices : ""); |
| 1395 | packet_send(); |
| 1396 | |
| 1397 | dispatch_set(SSH2_MSG_USERAUTH_INFO_REQUEST, &input_userauth_info_req); |
| 1398 | return 1; |
| 1399 | } |
| 1400 | |
| 1401 | /* |
| 1402 | * parse INFO_REQUEST, prompt user and send INFO_RESPONSE |
| 1403 | */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1404 | int |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1405 | input_userauth_info_req(int type, u_int32_t seq, void *ctxt) |
| 1406 | { |
| 1407 | Authctxt *authctxt = ctxt; |
| 1408 | char *name, *inst, *lang, *prompt, *response; |
| 1409 | u_int num_prompts, i; |
| 1410 | int echo = 0; |
| 1411 | |
| 1412 | debug2("input_userauth_info_req"); |
| 1413 | |
| 1414 | if (authctxt == NULL) |
| 1415 | fatal("input_userauth_info_req: no authentication context"); |
| 1416 | |
| 1417 | authctxt->info_req_seen = 1; |
| 1418 | |
| 1419 | name = packet_get_string(NULL); |
| 1420 | inst = packet_get_string(NULL); |
| 1421 | lang = packet_get_string(NULL); |
| 1422 | if (strlen(name) > 0) |
| 1423 | logit("%s", name); |
| 1424 | if (strlen(inst) > 0) |
| 1425 | logit("%s", inst); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1426 | free(name); |
| 1427 | free(inst); |
| 1428 | free(lang); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1429 | |
| 1430 | num_prompts = packet_get_int(); |
| 1431 | /* |
| 1432 | * Begin to build info response packet based on prompts requested. |
| 1433 | * We commit to providing the correct number of responses, so if |
| 1434 | * further on we run into a problem that prevents this, we have to |
| 1435 | * be sure and clean this up and send a correct error response. |
| 1436 | */ |
| 1437 | packet_start(SSH2_MSG_USERAUTH_INFO_RESPONSE); |
| 1438 | packet_put_int(num_prompts); |
| 1439 | |
| 1440 | debug2("input_userauth_info_req: num_prompts %d", num_prompts); |
| 1441 | for (i = 0; i < num_prompts; i++) { |
| 1442 | prompt = packet_get_string(NULL); |
| 1443 | echo = packet_get_char(); |
| 1444 | |
| 1445 | response = read_passphrase(prompt, echo ? RP_ECHO : 0); |
| 1446 | |
| 1447 | packet_put_cstring(response); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1448 | explicit_bzero(response, strlen(response)); |
| 1449 | free(response); |
| 1450 | free(prompt); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1451 | } |
| 1452 | packet_check_eom(); /* done with parsing incoming message. */ |
| 1453 | |
| 1454 | packet_add_padding(64); |
| 1455 | packet_send(); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1456 | return 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1457 | } |
| 1458 | |
| 1459 | static int |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1460 | ssh_keysign(struct sshkey *key, u_char **sigp, size_t *lenp, |
| 1461 | const u_char *data, size_t datalen) |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1462 | { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1463 | struct sshbuf *b; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1464 | struct stat st; |
| 1465 | pid_t pid; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1466 | int i, r, to[2], from[2], status, sock = packet_get_connection_in(); |
| 1467 | u_char rversion = 0, version = 2; |
| 1468 | void (*osigchld)(int); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1469 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1470 | *sigp = NULL; |
| 1471 | *lenp = 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1472 | |
| 1473 | if (stat(_PATH_SSH_KEY_SIGN, &st) < 0) { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1474 | error("%s: not installed: %s", __func__, strerror(errno)); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1475 | return -1; |
| 1476 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1477 | if (fflush(stdout) != 0) { |
| 1478 | error("%s: fflush: %s", __func__, strerror(errno)); |
| 1479 | return -1; |
| 1480 | } |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1481 | if (pipe(to) < 0) { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1482 | error("%s: pipe: %s", __func__, strerror(errno)); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1483 | return -1; |
| 1484 | } |
| 1485 | if (pipe(from) < 0) { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1486 | error("%s: pipe: %s", __func__, strerror(errno)); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1487 | return -1; |
| 1488 | } |
| 1489 | if ((pid = fork()) < 0) { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1490 | error("%s: fork: %s", __func__, strerror(errno)); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1491 | return -1; |
| 1492 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1493 | osigchld = signal(SIGCHLD, SIG_DFL); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1494 | if (pid == 0) { |
| 1495 | /* keep the socket on exec */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1496 | fcntl(sock, F_SETFD, 0); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1497 | permanently_drop_suid(getuid()); |
| 1498 | close(from[0]); |
| 1499 | if (dup2(from[1], STDOUT_FILENO) < 0) |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1500 | fatal("%s: dup2: %s", __func__, strerror(errno)); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1501 | close(to[1]); |
| 1502 | if (dup2(to[0], STDIN_FILENO) < 0) |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1503 | fatal("%s: dup2: %s", __func__, strerror(errno)); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1504 | close(from[1]); |
| 1505 | close(to[0]); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1506 | /* Close everything but stdio and the socket */ |
| 1507 | for (i = STDERR_FILENO + 1; i < sock; i++) |
| 1508 | close(i); |
| 1509 | closefrom(sock + 1); |
| 1510 | debug3("%s: [child] pid=%ld, exec %s", |
| 1511 | __func__, (long)getpid(), _PATH_SSH_KEY_SIGN); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1512 | execl(_PATH_SSH_KEY_SIGN, _PATH_SSH_KEY_SIGN, (char *) 0); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1513 | fatal("%s: exec(%s): %s", __func__, _PATH_SSH_KEY_SIGN, |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1514 | strerror(errno)); |
| 1515 | } |
| 1516 | close(from[1]); |
| 1517 | close(to[0]); |
| 1518 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1519 | if ((b = sshbuf_new()) == NULL) |
| 1520 | fatal("%s: sshbuf_new failed", __func__); |
| 1521 | /* send # of sock, data to be signed */ |
| 1522 | if ((r = sshbuf_put_u32(b, sock) != 0) || |
| 1523 | (r = sshbuf_put_string(b, data, datalen)) != 0) |
| 1524 | fatal("%s: buffer error: %s", __func__, ssh_err(r)); |
| 1525 | if (ssh_msg_send(to[1], version, b) == -1) |
| 1526 | fatal("%s: couldn't send request", __func__); |
| 1527 | sshbuf_reset(b); |
| 1528 | r = ssh_msg_recv(from[0], b); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1529 | close(from[0]); |
| 1530 | close(to[1]); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1531 | if (r < 0) { |
| 1532 | error("%s: no reply", __func__); |
| 1533 | goto fail; |
| 1534 | } |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1535 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1536 | errno = 0; |
| 1537 | while (waitpid(pid, &status, 0) < 0) { |
| 1538 | if (errno != EINTR) { |
| 1539 | error("%s: waitpid %ld: %s", |
| 1540 | __func__, (long)pid, strerror(errno)); |
| 1541 | goto fail; |
| 1542 | } |
| 1543 | } |
| 1544 | if (!WIFEXITED(status)) { |
| 1545 | error("%s: exited abnormally", __func__); |
| 1546 | goto fail; |
| 1547 | } |
| 1548 | if (WEXITSTATUS(status) != 0) { |
| 1549 | error("%s: exited with status %d", |
| 1550 | __func__, WEXITSTATUS(status)); |
| 1551 | goto fail; |
| 1552 | } |
| 1553 | if ((r = sshbuf_get_u8(b, &rversion)) != 0) { |
| 1554 | error("%s: buffer error: %s", __func__, ssh_err(r)); |
| 1555 | goto fail; |
| 1556 | } |
| 1557 | if (rversion != version) { |
| 1558 | error("%s: bad version", __func__); |
| 1559 | goto fail; |
| 1560 | } |
| 1561 | if ((r = sshbuf_get_string(b, sigp, lenp)) != 0) { |
| 1562 | error("%s: buffer error: %s", __func__, ssh_err(r)); |
| 1563 | fail: |
| 1564 | signal(SIGCHLD, osigchld); |
| 1565 | sshbuf_free(b); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1566 | return -1; |
| 1567 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1568 | signal(SIGCHLD, osigchld); |
| 1569 | sshbuf_free(b); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1570 | |
| 1571 | return 0; |
| 1572 | } |
| 1573 | |
| 1574 | int |
| 1575 | userauth_hostbased(Authctxt *authctxt) |
| 1576 | { |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1577 | struct ssh *ssh = active_state; |
| 1578 | struct sshkey *private = NULL; |
| 1579 | struct sshbuf *b = NULL; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1580 | const char *service; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1581 | u_char *sig = NULL, *keyblob = NULL; |
| 1582 | char *fp = NULL, *chost = NULL, *lname = NULL; |
| 1583 | size_t siglen = 0, keylen = 0; |
| 1584 | int i, r, success = 0; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1585 | |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1586 | if (authctxt->ktypes == NULL) { |
| 1587 | authctxt->oktypes = xstrdup(options.hostbased_key_types); |
| 1588 | authctxt->ktypes = authctxt->oktypes; |
| 1589 | } |
| 1590 | |
| 1591 | /* |
| 1592 | * Work through each listed type pattern in HostbasedKeyTypes, |
| 1593 | * trying each hostkey that matches the type in turn. |
| 1594 | */ |
| 1595 | for (;;) { |
| 1596 | if (authctxt->active_ktype == NULL) |
| 1597 | authctxt->active_ktype = strsep(&authctxt->ktypes, ","); |
| 1598 | if (authctxt->active_ktype == NULL || |
| 1599 | *authctxt->active_ktype == '\0') |
| 1600 | break; |
| 1601 | debug3("%s: trying key type %s", __func__, |
| 1602 | authctxt->active_ktype); |
| 1603 | |
| 1604 | /* check for a useful key */ |
| 1605 | private = NULL; |
| 1606 | for (i = 0; i < authctxt->sensitive->nkeys; i++) { |
| 1607 | if (authctxt->sensitive->keys[i] == NULL || |
| 1608 | authctxt->sensitive->keys[i]->type == KEY_RSA1 || |
| 1609 | authctxt->sensitive->keys[i]->type == KEY_UNSPEC) |
| 1610 | continue; |
| 1611 | if (match_pattern_list( |
| 1612 | sshkey_ssh_name(authctxt->sensitive->keys[i]), |
| 1613 | authctxt->active_ktype, |
| 1614 | strlen(authctxt->active_ktype), 0) != 1) |
| 1615 | continue; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1616 | /* we take and free the key */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1617 | private = authctxt->sensitive->keys[i]; |
| 1618 | authctxt->sensitive->keys[i] = NULL; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1619 | break; |
| 1620 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1621 | /* Found one */ |
| 1622 | if (private != NULL) |
| 1623 | break; |
| 1624 | /* No more keys of this type; advance */ |
| 1625 | authctxt->active_ktype = NULL; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1626 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1627 | if (private == NULL) { |
| 1628 | free(authctxt->oktypes); |
| 1629 | authctxt->oktypes = authctxt->ktypes = NULL; |
| 1630 | authctxt->active_ktype = NULL; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1631 | debug("No more client hostkeys for hostbased authentication."); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1632 | goto out; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1633 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1634 | |
| 1635 | if ((fp = sshkey_fingerprint(private, options.fingerprint_hash, |
| 1636 | SSH_FP_DEFAULT)) == NULL) { |
| 1637 | error("%s: sshkey_fingerprint failed", __func__); |
| 1638 | goto out; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1639 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1640 | debug("%s: trying hostkey %s %s", |
| 1641 | __func__, sshkey_ssh_name(private), fp); |
| 1642 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1643 | /* figure out a name for the client host */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1644 | if ((lname = get_local_name(packet_get_connection_in())) == NULL) { |
| 1645 | error("%s: cannot get local ipaddr/name", __func__); |
| 1646 | goto out; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1647 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1648 | |
| 1649 | /* XXX sshbuf_put_stringf? */ |
| 1650 | xasprintf(&chost, "%s.", lname); |
| 1651 | debug2("%s: chost %s", __func__, chost); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1652 | |
| 1653 | service = datafellows & SSH_BUG_HBSERVICE ? "ssh-userauth" : |
| 1654 | authctxt->service; |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1655 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1656 | /* construct data */ |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1657 | if ((b = sshbuf_new()) == NULL) { |
| 1658 | error("%s: sshbuf_new failed", __func__); |
| 1659 | goto out; |
| 1660 | } |
| 1661 | if ((r = sshkey_to_blob(private, &keyblob, &keylen)) != 0) { |
| 1662 | error("%s: sshkey_to_blob: %s", __func__, ssh_err(r)); |
| 1663 | goto out; |
| 1664 | } |
| 1665 | if ((r = sshbuf_put_string(b, session_id2, session_id2_len)) != 0 || |
| 1666 | (r = sshbuf_put_u8(b, SSH2_MSG_USERAUTH_REQUEST)) != 0 || |
| 1667 | (r = sshbuf_put_cstring(b, authctxt->server_user)) != 0 || |
| 1668 | (r = sshbuf_put_cstring(b, service)) != 0 || |
| 1669 | (r = sshbuf_put_cstring(b, authctxt->method->name)) != 0 || |
| 1670 | (r = sshbuf_put_cstring(b, key_ssh_name(private))) != 0 || |
| 1671 | (r = sshbuf_put_string(b, keyblob, keylen)) != 0 || |
| 1672 | (r = sshbuf_put_cstring(b, chost)) != 0 || |
| 1673 | (r = sshbuf_put_cstring(b, authctxt->local_user)) != 0) { |
| 1674 | error("%s: buffer error: %s", __func__, ssh_err(r)); |
| 1675 | goto out; |
| 1676 | } |
| 1677 | |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1678 | #ifdef DEBUG_PK |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1679 | sshbuf_dump(b, stderr); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1680 | #endif |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1681 | if (authctxt->sensitive->external_keysign) |
| 1682 | r = ssh_keysign(private, &sig, &siglen, |
| 1683 | sshbuf_ptr(b), sshbuf_len(b)); |
| 1684 | else if ((r = sshkey_sign(private, &sig, &siglen, |
| 1685 | sshbuf_ptr(b), sshbuf_len(b), datafellows)) != 0) |
| 1686 | debug("%s: sshkey_sign: %s", __func__, ssh_err(r)); |
| 1687 | if (r != 0) { |
| 1688 | error("sign using hostkey %s %s failed", |
| 1689 | sshkey_ssh_name(private), fp); |
| 1690 | goto out; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1691 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1692 | if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 || |
| 1693 | (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 || |
| 1694 | (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 || |
| 1695 | (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 || |
| 1696 | (r = sshpkt_put_cstring(ssh, key_ssh_name(private))) != 0 || |
| 1697 | (r = sshpkt_put_string(ssh, keyblob, keylen)) != 0 || |
| 1698 | (r = sshpkt_put_cstring(ssh, chost)) != 0 || |
| 1699 | (r = sshpkt_put_cstring(ssh, authctxt->local_user)) != 0 || |
| 1700 | (r = sshpkt_put_string(ssh, sig, siglen)) != 0 || |
| 1701 | (r = sshpkt_send(ssh)) != 0) { |
| 1702 | error("%s: packet error: %s", __func__, ssh_err(r)); |
| 1703 | goto out; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1704 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1705 | success = 1; |
| 1706 | |
| 1707 | out: |
| 1708 | if (sig != NULL) { |
| 1709 | explicit_bzero(sig, siglen); |
| 1710 | free(sig); |
| 1711 | } |
| 1712 | free(keyblob); |
| 1713 | free(lname); |
| 1714 | free(fp); |
| 1715 | free(chost); |
| 1716 | sshkey_free(private); |
| 1717 | sshbuf_free(b); |
| 1718 | |
| 1719 | return success; |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1720 | } |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1721 | |
| 1722 | /* find auth method */ |
| 1723 | |
| 1724 | /* |
| 1725 | * given auth method name, if configurable options permit this method fill |
| 1726 | * in auth_ident field and return true, otherwise return false. |
| 1727 | */ |
| 1728 | static int |
| 1729 | authmethod_is_enabled(Authmethod *method) |
| 1730 | { |
| 1731 | if (method == NULL) |
| 1732 | return 0; |
| 1733 | /* return false if options indicate this method is disabled */ |
| 1734 | if (method->enabled == NULL || *method->enabled == 0) |
| 1735 | return 0; |
| 1736 | /* return false if batch mode is enabled but method needs interactive mode */ |
| 1737 | if (method->batch_flag != NULL && *method->batch_flag != 0) |
| 1738 | return 0; |
| 1739 | return 1; |
| 1740 | } |
| 1741 | |
| 1742 | static Authmethod * |
| 1743 | authmethod_lookup(const char *name) |
| 1744 | { |
| 1745 | Authmethod *method = NULL; |
| 1746 | if (name != NULL) |
| 1747 | for (method = authmethods; method->name != NULL; method++) |
| 1748 | if (strcmp(name, method->name) == 0) |
| 1749 | return method; |
| 1750 | debug2("Unrecognized authentication method name: %s", name ? name : "NULL"); |
| 1751 | return NULL; |
| 1752 | } |
| 1753 | |
| 1754 | /* XXX internal state */ |
| 1755 | static Authmethod *current = NULL; |
| 1756 | static char *supported = NULL; |
| 1757 | static char *preferred = NULL; |
| 1758 | |
| 1759 | /* |
| 1760 | * Given the authentication method list sent by the server, return the |
| 1761 | * next method we should try. If the server initially sends a nil list, |
| 1762 | * use a built-in default list. |
| 1763 | */ |
| 1764 | static Authmethod * |
| 1765 | authmethod_get(char *authlist) |
| 1766 | { |
| 1767 | char *name = NULL; |
| 1768 | u_int next; |
| 1769 | |
| 1770 | /* Use a suitable default if we're passed a nil list. */ |
| 1771 | if (authlist == NULL || strlen(authlist) == 0) |
| 1772 | authlist = options.preferred_authentications; |
| 1773 | |
| 1774 | if (supported == NULL || strcmp(authlist, supported) != 0) { |
| 1775 | debug3("start over, passed a different list %s", authlist); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1776 | free(supported); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1777 | supported = xstrdup(authlist); |
| 1778 | preferred = options.preferred_authentications; |
| 1779 | debug3("preferred %s", preferred); |
| 1780 | current = NULL; |
| 1781 | } else if (current != NULL && authmethod_is_enabled(current)) |
| 1782 | return current; |
| 1783 | |
| 1784 | for (;;) { |
| 1785 | if ((name = match_list(preferred, supported, &next)) == NULL) { |
| 1786 | debug("No more authentication methods to try."); |
| 1787 | current = NULL; |
| 1788 | return NULL; |
| 1789 | } |
| 1790 | preferred += next; |
| 1791 | debug3("authmethod_lookup %s", name); |
| 1792 | debug3("remaining preferred: %s", preferred); |
| 1793 | if ((current = authmethod_lookup(name)) != NULL && |
| 1794 | authmethod_is_enabled(current)) { |
| 1795 | debug3("authmethod_is_enabled %s", name); |
| 1796 | debug("Next authentication method: %s", name); |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1797 | free(name); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1798 | return current; |
| 1799 | } |
Adam Langley | d059297 | 2015-03-30 14:49:51 -0700 | [diff] [blame] | 1800 | free(name); |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1801 | } |
Greg Hartman | bd77cf7 | 2015-02-25 13:21:06 -0800 | [diff] [blame] | 1802 | } |
| 1803 | |
| 1804 | static char * |
| 1805 | authmethods_get(void) |
| 1806 | { |
| 1807 | Authmethod *method = NULL; |
| 1808 | Buffer b; |
| 1809 | char *list; |
| 1810 | |
| 1811 | buffer_init(&b); |
| 1812 | for (method = authmethods; method->name != NULL; method++) { |
| 1813 | if (authmethod_is_enabled(method)) { |
| 1814 | if (buffer_len(&b) > 0) |
| 1815 | buffer_append(&b, ",", 1); |
| 1816 | buffer_append(&b, method->name, strlen(method->name)); |
| 1817 | } |
| 1818 | } |
| 1819 | buffer_append(&b, "\0", 1); |
| 1820 | list = xstrdup(buffer_ptr(&b)); |
| 1821 | buffer_free(&b); |
| 1822 | return list; |
| 1823 | } |
| 1824 | |