Annotation of src/usr.bin/ssh/sshconnect2.c, Revision 1.296
1.296 ! djm 1: /* $OpenBSD: sshconnect2.c,v 1.295 2019/01/19 21:40:21 djm Exp $ */
1.1 markus 2: /*
3: * Copyright (c) 2000 Markus Friedl. All rights reserved.
1.170 djm 4: * Copyright (c) 2008 Damien Miller. All rights reserved.
1.1 markus 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:
1.145 stevesk 27: #include <sys/types.h>
1.160 deraadt 28: #include <sys/socket.h>
1.145 stevesk 29: #include <sys/wait.h>
1.144 stevesk 30: #include <sys/queue.h>
1.146 stevesk 31: #include <sys/stat.h>
1.156 stevesk 32:
33: #include <errno.h>
1.174 dtucker 34: #include <fcntl.h>
1.164 jolan 35: #include <netdb.h>
1.159 stevesk 36: #include <stdio.h>
1.158 stevesk 37: #include <string.h>
1.160 deraadt 38: #include <signal.h>
39: #include <pwd.h>
1.157 stevesk 40: #include <unistd.h>
1.166 djm 41: #include <vis.h>
1.1 markus 42:
1.160 deraadt 43: #include "xmalloc.h"
1.1 markus 44: #include "ssh.h"
1.37 markus 45: #include "ssh2.h"
1.278 markus 46: #include "sshbuf.h"
1.1 markus 47: #include "packet.h"
48: #include "compat.h"
1.37 markus 49: #include "cipher.h"
1.278 markus 50: #include "sshkey.h"
1.1 markus 51: #include "kex.h"
52: #include "myproposal.h"
53: #include "sshconnect.h"
54: #include "authfile.h"
1.57 provos 55: #include "dh.h"
1.17 markus 56: #include "authfd.h"
1.37 markus 57: #include "log.h"
1.210 millert 58: #include "misc.h"
1.37 markus 59: #include "readconf.h"
1.53 markus 60: #include "match.h"
1.61 markus 61: #include "dispatch.h"
1.68 markus 62: #include "canohost.h"
1.100 markus 63: #include "msg.h"
64: #include "pathnames.h"
1.154 markus 65: #include "uidswap.h"
1.186 djm 66: #include "hostfile.h"
1.214 djm 67: #include "ssherr.h"
1.246 djm 68: #include "utf8.h"
1.22 provos 69:
1.121 markus 70: #ifdef GSSAPI
71: #include "ssh-gss.h"
72: #endif
1.293 djm 73:
1.1 markus 74: /* import */
75: extern char *client_version_string;
76: extern char *server_version_string;
77: extern Options options;
78:
79: /*
80: * SSH2 key exchange
81: */
82:
1.32 markus 83: u_char *session_id2 = NULL;
1.120 markus 84: u_int session_id2_len = 0;
1.1 markus 85:
1.61 markus 86: char *xxx_host;
87: struct sockaddr *xxx_hostaddr;
88:
1.76 itojun 89: static int
1.259 markus 90: verify_host_key_callback(struct sshkey *hostkey, struct ssh *ssh)
1.61 markus 91: {
1.75 markus 92: if (verify_host_key(xxx_host, xxx_hostaddr, hostkey) == -1)
1.83 markus 93: fatal("Host key verification failed.");
1.61 markus 94: return 0;
95: }
96:
1.186 djm 97: static char *
98: order_hostkeyalgs(char *host, struct sockaddr *hostaddr, u_short port)
99: {
100: char *oavail, *avail, *first, *last, *alg, *hostname, *ret;
101: size_t maxlen;
102: struct hostkeys *hostkeys;
103: int ktype;
1.188 djm 104: u_int i;
1.186 djm 105:
106: /* Find all hostkeys for this hostname */
107: get_hostfile_hostname_ipaddr(host, hostaddr, port, &hostname, NULL);
108: hostkeys = init_hostkeys();
1.188 djm 109: for (i = 0; i < options.num_user_hostfiles; i++)
110: load_hostkeys(hostkeys, hostname, options.user_hostfiles[i]);
111: for (i = 0; i < options.num_system_hostfiles; i++)
112: load_hostkeys(hostkeys, hostname, options.system_hostfiles[i]);
1.186 djm 113:
114: oavail = avail = xstrdup(KEX_DEFAULT_PK_ALG);
115: maxlen = strlen(avail) + 1;
116: first = xmalloc(maxlen);
117: last = xmalloc(maxlen);
118: *first = *last = '\0';
119:
120: #define ALG_APPEND(to, from) \
121: do { \
122: if (*to != '\0') \
123: strlcat(to, ",", maxlen); \
124: strlcat(to, from, maxlen); \
125: } while (0)
126:
127: while ((alg = strsep(&avail, ",")) && *alg != '\0') {
1.214 djm 128: if ((ktype = sshkey_type_from_name(alg)) == KEY_UNSPEC)
1.186 djm 129: fatal("%s: unknown alg %s", __func__, alg);
130: if (lookup_key_in_hostkeys_by_type(hostkeys,
1.214 djm 131: sshkey_type_plain(ktype), NULL))
1.186 djm 132: ALG_APPEND(first, alg);
133: else
134: ALG_APPEND(last, alg);
135: }
136: #undef ALG_APPEND
1.216 djm 137: xasprintf(&ret, "%s%s%s", first,
138: (*first == '\0' || *last == '\0') ? "" : ",", last);
1.186 djm 139: if (*first != '\0')
140: debug3("%s: prefer hostkeyalgs: %s", __func__, first);
141:
1.197 djm 142: free(first);
143: free(last);
144: free(hostname);
145: free(oavail);
1.186 djm 146: free_hostkeys(hostkeys);
147:
148: return ret;
149: }
150:
1.1 markus 151: void
1.291 djm 152: ssh_kex2(struct ssh *ssh, char *host, struct sockaddr *hostaddr, u_short port)
1.22 provos 153: {
1.205 markus 154: char *myproposal[PROPOSAL_MAX] = { KEX_CLIENT };
1.275 djm 155: char *s, *all_key;
1.221 markus 156: int r;
1.61 markus 157:
158: xxx_host = host;
159: xxx_hostaddr = hostaddr;
1.22 provos 160:
1.231 markus 161: if ((s = kex_names_cat(options.kex_algorithms, "ext-info-c")) == NULL)
162: fatal("%s: kex_names_cat", __func__);
1.284 djm 163: myproposal[PROPOSAL_KEX_ALGS] = compat_kex_proposal(s);
1.60 stevesk 164: myproposal[PROPOSAL_ENC_ALGS_CTOS] =
1.284 djm 165: compat_cipher_proposal(options.ciphers);
1.60 stevesk 166: myproposal[PROPOSAL_ENC_ALGS_STOC] =
1.284 djm 167: compat_cipher_proposal(options.ciphers);
1.245 dtucker 168: myproposal[PROPOSAL_COMP_ALGS_CTOS] =
169: myproposal[PROPOSAL_COMP_ALGS_STOC] = options.compression ?
1.277 sf 170: "zlib@openssh.com,zlib,none" : "none,zlib@openssh.com,zlib";
1.226 djm 171: myproposal[PROPOSAL_MAC_ALGS_CTOS] =
172: myproposal[PROPOSAL_MAC_ALGS_STOC] = options.macs;
173: if (options.hostkeyalgorithms != NULL) {
1.275 djm 174: all_key = sshkey_alg_list(0, 0, 1, ',');
175: if (kex_assemble_names(&options.hostkeyalgorithms,
176: KEX_DEFAULT_PK_ALG, all_key) != 0)
1.226 djm 177: fatal("%s: kex_assemble_namelist", __func__);
1.275 djm 178: free(all_key);
1.88 deraadt 179: myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] =
1.284 djm 180: compat_pkalg_proposal(options.hostkeyalgorithms);
1.226 djm 181: } else {
1.225 markus 182: /* Enforce default */
183: options.hostkeyalgorithms = xstrdup(KEX_DEFAULT_PK_ALG);
1.186 djm 184: /* Prefer algorithms that we already have keys for */
185: myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] =
1.200 djm 186: compat_pkalg_proposal(
1.284 djm 187: order_hostkeyalgs(host, hostaddr, port));
1.186 djm 188: }
1.115 markus 189:
1.196 dtucker 190: if (options.rekey_limit || options.rekey_interval)
1.294 djm 191: ssh_packet_set_rekey_limits(ssh, options.rekey_limit,
1.254 dtucker 192: options.rekey_interval);
1.22 provos 193:
1.65 markus 194: /* start key exchange */
1.291 djm 195: if ((r = kex_setup(ssh, myproposal)) != 0)
1.221 markus 196: fatal("kex_setup: %s", ssh_err(r));
1.207 markus 197: #ifdef WITH_OPENSSL
1.291 djm 198: ssh->kex->kex[KEX_DH_GRP1_SHA1] = kexdh_client;
199: ssh->kex->kex[KEX_DH_GRP14_SHA1] = kexdh_client;
200: ssh->kex->kex[KEX_DH_GRP14_SHA256] = kexdh_client;
201: ssh->kex->kex[KEX_DH_GRP16_SHA512] = kexdh_client;
202: ssh->kex->kex[KEX_DH_GRP18_SHA512] = kexdh_client;
203: ssh->kex->kex[KEX_DH_GEX_SHA1] = kexgex_client;
204: ssh->kex->kex[KEX_DH_GEX_SHA256] = kexgex_client;
205: ssh->kex->kex[KEX_ECDH_SHA2] = kexecdh_client;
1.207 markus 206: #endif
1.291 djm 207: ssh->kex->kex[KEX_C25519_SHA256] = kexc25519_client;
208: ssh->kex->verify_host_key=&verify_host_key_callback;
1.22 provos 209:
1.291 djm 210: ssh_dispatch_run_fatal(ssh, DISPATCH_BLOCK, &ssh->kex->done);
1.173 andreas 211:
1.231 markus 212: /* remove ext-info from the KEX proposals for rekeying */
213: myproposal[PROPOSAL_KEX_ALGS] =
1.284 djm 214: compat_kex_proposal(options.kex_algorithms);
1.291 djm 215: if ((r = kex_prop2buf(ssh->kex->my, myproposal)) != 0)
1.231 markus 216: fatal("kex_prop2buf: %s", ssh_err(r));
1.62 markus 217:
1.291 djm 218: session_id2 = ssh->kex->session_id;
219: session_id2_len = ssh->kex->session_id_len;
1.22 provos 220:
221: #ifdef DEBUG_KEXDH
222: /* send 1st encrypted/maced/compressed message */
1.278 markus 223: if ((r = sshpkt_start(ssh, SSH2_MSG_IGNORE)) != 0 ||
224: (r = sshpkt_put_cstring(ssh, "markus")) != 0 ||
1.280 markus 225: (r = sshpkt_send(ssh)) != 0 ||
226: (r = ssh_packet_write_wait(ssh)) != 0)
1.278 markus 227: fatal("%s: %s", __func__, ssh_err(r));
1.22 provos 228: #endif
1.1 markus 229: }
1.11 markus 230:
1.1 markus 231: /*
232: * Authenticate user
233: */
1.20 markus 234:
1.214 djm 235: typedef struct cauthctxt Authctxt;
236: typedef struct cauthmethod Authmethod;
1.117 markus 237: typedef struct identity Identity;
238: typedef struct idlist Idlist;
1.20 markus 239:
1.117 markus 240: struct identity {
241: TAILQ_ENTRY(identity) next;
1.214 djm 242: int agent_fd; /* >=0 if agent supports key */
243: struct sshkey *key; /* public/private key */
1.117 markus 244: char *filename; /* comment for agent-only keys */
245: int tried;
246: int isprivate; /* key points to the private key */
1.191 dtucker 247: int userprovided;
1.117 markus 248: };
249: TAILQ_HEAD(idlist, identity);
1.20 markus 250:
1.214 djm 251: struct cauthctxt {
1.20 markus 252: const char *server_user;
1.68 markus 253: const char *local_user;
1.20 markus 254: const char *host;
255: const char *service;
1.214 djm 256: struct cauthmethod *method;
1.183 djm 257: sig_atomic_t success;
1.51 markus 258: char *authlist;
1.68 markus 259: /* pubkey */
1.214 djm 260: struct idlist keys;
261: int agent_fd;
1.68 markus 262: /* hostbased */
1.100 markus 263: Sensitive *sensitive;
1.223 djm 264: char *oktypes, *ktypes;
265: const char *active_ktype;
1.82 markus 266: /* kbd-interactive */
267: int info_req_seen;
1.292 djm 268: int attempt_kbdint;
269: /* password */
270: int attempt_passwd;
1.121 markus 271: /* generic */
272: void *methoddata;
1.20 markus 273: };
1.214 djm 274:
275: struct cauthmethod {
1.20 markus 276: char *name; /* string to compare against server's list */
1.295 djm 277: int (*userauth)(struct ssh *ssh);
278: void (*cleanup)(struct ssh *ssh);
1.20 markus 279: int *enabled; /* flag in option struct that enables method */
280: int *batch_flag; /* flag in option struct that disables method */
281: };
282:
1.261 markus 283: int input_userauth_service_accept(int, u_int32_t, struct ssh *);
284: int input_userauth_ext_info(int, u_int32_t, struct ssh *);
285: int input_userauth_success(int, u_int32_t, struct ssh *);
286: int input_userauth_success_unexpected(int, u_int32_t, struct ssh *);
287: int input_userauth_failure(int, u_int32_t, struct ssh *);
288: int input_userauth_banner(int, u_int32_t, struct ssh *);
289: int input_userauth_error(int, u_int32_t, struct ssh *);
290: int input_userauth_info_req(int, u_int32_t, struct ssh *);
291: int input_userauth_pk_ok(int, u_int32_t, struct ssh *);
292: int input_userauth_passwd_changereq(int, u_int32_t, struct ssh *);
1.86 itojun 293:
1.295 djm 294: int userauth_none(struct ssh *);
295: int userauth_pubkey(struct ssh *);
296: int userauth_passwd(struct ssh *);
297: int userauth_kbdint(struct ssh *);
298: int userauth_hostbased(struct ssh *);
1.20 markus 299:
1.121 markus 300: #ifdef GSSAPI
1.295 djm 301: int userauth_gssapi(struct ssh *);
1.261 markus 302: int input_gssapi_response(int type, u_int32_t, struct ssh *);
303: int input_gssapi_token(int type, u_int32_t, struct ssh *);
304: int input_gssapi_hash(int type, u_int32_t, struct ssh *);
305: int input_gssapi_error(int, u_int32_t, struct ssh *);
306: int input_gssapi_errtok(int, u_int32_t, struct ssh *);
1.121 markus 307: #endif
308:
1.295 djm 309: void userauth(struct ssh *, char *);
1.51 markus 310:
1.295 djm 311: static int sign_and_send_pubkey(struct ssh *ssh, Identity *);
1.117 markus 312: static void pubkey_prepare(Authctxt *);
313: static void pubkey_cleanup(Authctxt *);
1.251 djm 314: static void pubkey_reset(Authctxt *);
1.259 markus 315: static struct sshkey *load_identity_file(Identity *);
1.76 itojun 316:
317: static Authmethod *authmethod_get(char *authlist);
318: static Authmethod *authmethod_lookup(const char *name);
319: static char *authmethods_get(void);
1.20 markus 320:
321: Authmethod authmethods[] = {
1.121 markus 322: #ifdef GSSAPI
1.132 markus 323: {"gssapi-with-mic",
1.121 markus 324: userauth_gssapi,
1.170 djm 325: NULL,
1.121 markus 326: &options.gss_authentication,
327: NULL},
328: #endif
1.81 markus 329: {"hostbased",
330: userauth_hostbased,
1.170 djm 331: NULL,
1.81 markus 332: &options.hostbased_authentication,
333: NULL},
1.20 markus 334: {"publickey",
335: userauth_pubkey,
1.170 djm 336: NULL,
1.28 markus 337: &options.pubkey_authentication,
1.20 markus 338: NULL},
1.81 markus 339: {"keyboard-interactive",
340: userauth_kbdint,
1.170 djm 341: NULL,
1.81 markus 342: &options.kbd_interactive_authentication,
343: &options.batch_mode},
1.20 markus 344: {"password",
345: userauth_passwd,
1.170 djm 346: NULL,
1.20 markus 347: &options.password_authentication,
1.23 markus 348: &options.batch_mode},
349: {"none",
350: userauth_none,
351: NULL,
1.170 djm 352: NULL,
1.23 markus 353: NULL},
1.170 djm 354: {NULL, NULL, NULL, NULL, NULL}
1.20 markus 355: };
356:
357: void
1.291 djm 358: ssh_userauth2(struct ssh *ssh, const char *local_user,
359: const char *server_user, char *host, Sensitive *sensitive)
1.20 markus 360: {
361: Authctxt authctxt;
1.231 markus 362: int r;
1.39 markus 363:
1.73 markus 364: if (options.challenge_response_authentication)
1.39 markus 365: options.kbd_interactive_authentication = 1;
1.53 markus 366: if (options.preferred_authentications == NULL)
367: options.preferred_authentications = authmethods_get();
368:
1.20 markus 369: /* setup authentication context */
1.82 markus 370: memset(&authctxt, 0, sizeof(authctxt));
1.20 markus 371: authctxt.server_user = server_user;
1.68 markus 372: authctxt.local_user = local_user;
1.20 markus 373: authctxt.host = host;
374: authctxt.service = "ssh-connection"; /* service name */
375: authctxt.success = 0;
1.23 markus 376: authctxt.method = authmethod_lookup("none");
1.51 markus 377: authctxt.authlist = NULL;
1.121 markus 378: authctxt.methoddata = NULL;
1.100 markus 379: authctxt.sensitive = sensitive;
1.223 djm 380: authctxt.active_ktype = authctxt.oktypes = authctxt.ktypes = NULL;
1.82 markus 381: authctxt.info_req_seen = 0;
1.292 djm 382: authctxt.attempt_kbdint = 0;
383: authctxt.attempt_passwd = 0;
1.215 djm 384: authctxt.agent_fd = -1;
1.289 djm 385: pubkey_prepare(&authctxt);
1.291 djm 386: if (authctxt.method == NULL) {
387: fatal("%s: internal error: cannot send userauth none request",
388: __func__);
389: }
1.20 markus 390:
1.231 markus 391: if ((r = sshpkt_start(ssh, SSH2_MSG_SERVICE_REQUEST)) != 0 ||
392: (r = sshpkt_put_cstring(ssh, "ssh-userauth")) != 0 ||
393: (r = sshpkt_send(ssh)) != 0)
394: fatal("%s: %s", __func__, ssh_err(r));
395:
1.260 markus 396: ssh->authctxt = &authctxt;
1.231 markus 397: ssh_dispatch_init(ssh, &input_userauth_error);
398: ssh_dispatch_set(ssh, SSH2_MSG_EXT_INFO, &input_userauth_ext_info);
399: ssh_dispatch_set(ssh, SSH2_MSG_SERVICE_ACCEPT, &input_userauth_service_accept);
1.263 markus 400: ssh_dispatch_run_fatal(ssh, DISPATCH_BLOCK, &authctxt.success); /* loop until success */
1.260 markus 401: ssh->authctxt = NULL;
1.20 markus 402:
1.117 markus 403: pubkey_cleanup(&authctxt);
1.231 markus 404: ssh_dispatch_range(ssh, SSH2_MSG_USERAUTH_MIN, SSH2_MSG_USERAUTH_MAX, NULL);
1.119 markus 405:
1.248 dtucker 406: if (!authctxt.success)
407: fatal("Authentication failed.");
1.109 markus 408: debug("Authentication succeeded (%s).", authctxt.method->name);
1.20 markus 409: }
1.119 markus 410:
1.231 markus 411: /* ARGSUSED */
412: int
1.261 markus 413: input_userauth_service_accept(int type, u_int32_t seq, struct ssh *ssh)
1.231 markus 414: {
415: int r;
416:
417: if (ssh_packet_remaining(ssh) > 0) {
418: char *reply;
419:
420: if ((r = sshpkt_get_cstring(ssh, &reply, NULL)) != 0)
421: goto out;
422: debug2("service_accept: %s", reply);
423: free(reply);
424: } else {
425: debug2("buggy server: service_accept w/o service");
426: }
427: if ((r = sshpkt_get_end(ssh)) != 0)
428: goto out;
429: debug("SSH2_MSG_SERVICE_ACCEPT received");
430:
431: /* initial userauth request */
1.295 djm 432: userauth_none(ssh);
1.231 markus 433:
434: ssh_dispatch_set(ssh, SSH2_MSG_EXT_INFO, &input_userauth_error);
435: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_SUCCESS, &input_userauth_success);
436: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_FAILURE, &input_userauth_failure);
437: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_BANNER, &input_userauth_banner);
438: r = 0;
439: out:
440: return r;
441: }
442:
443: /* ARGSUSED */
444: int
1.261 markus 445: input_userauth_ext_info(int type, u_int32_t seqnr, struct ssh *ssh)
1.231 markus 446: {
1.261 markus 447: return kex_input_ext_info(type, seqnr, ssh);
1.231 markus 448: }
449:
1.20 markus 450: void
1.295 djm 451: userauth(struct ssh *ssh, char *authlist)
1.51 markus 452: {
1.295 djm 453: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.278 markus 454:
1.170 djm 455: if (authctxt->method != NULL && authctxt->method->cleanup != NULL)
1.295 djm 456: authctxt->method->cleanup(ssh);
1.170 djm 457:
1.197 djm 458: free(authctxt->methoddata);
459: authctxt->methoddata = NULL;
1.51 markus 460: if (authlist == NULL) {
461: authlist = authctxt->authlist;
462: } else {
1.197 djm 463: free(authctxt->authlist);
1.51 markus 464: authctxt->authlist = authlist;
465: }
466: for (;;) {
467: Authmethod *method = authmethod_get(authlist);
468: if (method == NULL)
1.264 dtucker 469: fatal("%s@%s: Permission denied (%s).",
470: authctxt->server_user, authctxt->host, authlist);
1.51 markus 471: authctxt->method = method;
1.119 markus 472:
473: /* reset the per method handler */
1.278 markus 474: ssh_dispatch_range(ssh, SSH2_MSG_USERAUTH_PER_METHOD_MIN,
1.119 markus 475: SSH2_MSG_USERAUTH_PER_METHOD_MAX, NULL);
476:
477: /* and try new method */
1.295 djm 478: if (method->userauth(ssh) != 0) {
1.51 markus 479: debug2("we sent a %s packet, wait for reply", method->name);
480: break;
481: } else {
482: debug2("we did not send a packet, disable method");
483: method->enabled = NULL;
484: }
485: }
486: }
1.105 deraadt 487:
1.169 djm 488: /* ARGSUSED */
1.218 markus 489: int
1.261 markus 490: input_userauth_error(int type, u_int32_t seq, struct ssh *ssh)
1.20 markus 491: {
1.295 djm 492: fatal("%s: bad message during authentication: type %d", __func__, type);
1.218 markus 493: return 0;
1.35 markus 494: }
1.105 deraadt 495:
1.169 djm 496: /* ARGSUSED */
1.218 markus 497: int
1.261 markus 498: input_userauth_banner(int type, u_int32_t seq, struct ssh *ssh)
1.35 markus 499: {
1.295 djm 500: char *msg = NULL;
1.294 djm 501: size_t len;
502: int r;
1.126 deraadt 503:
1.246 djm 504: debug3("%s", __func__);
1.294 djm 505: if ((r = sshpkt_get_cstring(ssh, &msg, &len)) != 0 ||
1.295 djm 506: (r = sshpkt_get_cstring(ssh, NULL, NULL)) != 0)
1.294 djm 507: goto out;
1.246 djm 508: if (len > 0 && options.log_level >= SYSLOG_LEVEL_INFO)
509: fmprintf(stderr, "%s", msg);
1.294 djm 510: r = 0;
511: out:
1.246 djm 512: free(msg);
1.294 djm 513: return r;
1.20 markus 514: }
1.105 deraadt 515:
1.169 djm 516: /* ARGSUSED */
1.218 markus 517: int
1.261 markus 518: input_userauth_success(int type, u_int32_t seq, struct ssh *ssh)
1.20 markus 519: {
1.260 markus 520: Authctxt *authctxt = ssh->authctxt;
1.172 djm 521:
1.20 markus 522: if (authctxt == NULL)
1.295 djm 523: fatal("%s: no authentication context", __func__);
1.197 djm 524: free(authctxt->authlist);
525: authctxt->authlist = NULL;
1.172 djm 526: if (authctxt->method != NULL && authctxt->method->cleanup != NULL)
1.295 djm 527: authctxt->method->cleanup(ssh);
1.197 djm 528: free(authctxt->methoddata);
529: authctxt->methoddata = NULL;
1.20 markus 530: authctxt->success = 1; /* break out */
1.218 markus 531: return 0;
1.20 markus 532: }
1.105 deraadt 533:
1.218 markus 534: int
1.261 markus 535: input_userauth_success_unexpected(int type, u_int32_t seq, struct ssh *ssh)
1.172 djm 536: {
1.260 markus 537: Authctxt *authctxt = ssh->authctxt;
1.172 djm 538:
539: if (authctxt == NULL)
540: fatal("%s: no authentication context", __func__);
541:
542: fatal("Unexpected authentication success during %s.",
543: authctxt->method->name);
1.218 markus 544: return 0;
1.172 djm 545: }
546:
1.169 djm 547: /* ARGSUSED */
1.218 markus 548: int
1.261 markus 549: input_userauth_failure(int type, u_int32_t seq, struct ssh *ssh)
1.20 markus 550: {
1.260 markus 551: Authctxt *authctxt = ssh->authctxt;
1.20 markus 552: char *authlist = NULL;
1.278 markus 553: u_char partial;
554: int r;
1.20 markus 555:
556: if (authctxt == NULL)
557: fatal("input_userauth_failure: no authentication context");
558:
1.278 markus 559: if ((r = sshpkt_get_cstring(ssh, &authlist, NULL)) != 0 ||
560: (r = sshpkt_get_u8(ssh, &partial)) != 0 ||
561: (r = sshpkt_get_end(ssh)) != 0)
562: goto out;
1.20 markus 563:
1.193 markus 564: if (partial != 0) {
1.247 dtucker 565: verbose("Authenticated with partial success.");
1.193 markus 566: /* reset state */
1.251 djm 567: pubkey_reset(authctxt);
1.193 markus 568: }
1.109 markus 569: debug("Authentications that can continue: %s", authlist);
1.20 markus 570:
1.295 djm 571: userauth(ssh, authlist);
1.278 markus 572: authlist = NULL;
573: out:
574: free(authlist);
1.218 markus 575: return 0;
1.51 markus 576: }
1.169 djm 577:
1.287 djm 578: /*
579: * Format an identity for logging including filename, key type, fingerprint
580: * and location (agent, etc.). Caller must free.
581: */
582: static char *
583: format_identity(Identity *id)
584: {
585: char *fp = NULL, *ret = NULL;
586:
587: if (id->key != NULL) {
588: fp = sshkey_fingerprint(id->key, options.fingerprint_hash,
589: SSH_FP_DEFAULT);
590: }
591: xasprintf(&ret, "%s %s%s%s%s%s%s",
592: id->filename,
593: id->key ? sshkey_type(id->key) : "", id->key ? " " : "",
594: fp ? fp : "",
595: id->userprovided ? " explicit" : "",
596: (id->key && (id->key->flags & SSHKEY_FLAG_EXT)) ? " token" : "",
597: id->agent_fd != -1 ? " agent" : "");
598: free(fp);
599: return ret;
600: }
601:
1.169 djm 602: /* ARGSUSED */
1.218 markus 603: int
1.261 markus 604: input_userauth_pk_ok(int type, u_int32_t seq, struct ssh *ssh)
1.51 markus 605: {
1.260 markus 606: Authctxt *authctxt = ssh->authctxt;
1.259 markus 607: struct sshkey *key = NULL;
1.117 markus 608: Identity *id = NULL;
1.287 djm 609: int pktype, found = 0, sent = 0;
1.278 markus 610: size_t blen;
1.287 djm 611: char *pkalg = NULL, *fp = NULL, *ident = NULL;
1.278 markus 612: u_char *pkblob = NULL;
613: int r;
1.51 markus 614:
615: if (authctxt == NULL)
616: fatal("input_userauth_pk_ok: no authentication context");
1.267 djm 617:
1.278 markus 618: if ((r = sshpkt_get_cstring(ssh, &pkalg, NULL)) != 0 ||
619: (r = sshpkt_get_string(ssh, &pkblob, &blen)) != 0 ||
620: (r = sshpkt_get_end(ssh)) != 0)
621: goto done;
1.51 markus 622:
1.278 markus 623: if ((pktype = sshkey_type_from_name(pkalg)) == KEY_UNSPEC) {
1.287 djm 624: debug("%s: server sent unknown pkalg %s", __func__, pkalg);
1.117 markus 625: goto done;
626: }
1.278 markus 627: if ((r = sshkey_from_blob(pkblob, blen, &key)) != 0) {
628: debug("no key from blob. pkalg %s: %s", pkalg, ssh_err(r));
1.117 markus 629: goto done;
630: }
631: if (key->type != pktype) {
632: error("input_userauth_pk_ok: type mismatch "
633: "for decoded key (received %d, expected %d)",
634: key->type, pktype);
635: goto done;
636: }
637:
1.127 markus 638: /*
639: * search keys in the reverse order, because last candidate has been
640: * moved to the end of the queue. this also avoids confusion by
641: * duplicate keys
642: */
1.136 henning 643: TAILQ_FOREACH_REVERSE(id, &authctxt->keys, idlist, next) {
1.278 markus 644: if (sshkey_equal(key, id->key)) {
1.287 djm 645: found = 1;
1.51 markus 646: break;
647: }
1.117 markus 648: }
1.287 djm 649: if (!found || id == NULL) {
650: fp = sshkey_fingerprint(key, options.fingerprint_hash,
651: SSH_FP_DEFAULT);
652: error("%s: server replied with unknown key: %s %s", __func__,
653: sshkey_type(key), fp == NULL ? "<ERROR>" : fp);
654: goto done;
655: }
656: ident = format_identity(id);
657: debug("Server accepts key: %s", ident);
1.295 djm 658: sent = sign_and_send_pubkey(ssh, id);
1.278 markus 659: r = 0;
660: done:
661: sshkey_free(key);
1.287 djm 662: free(ident);
663: free(fp);
1.197 djm 664: free(pkalg);
665: free(pkblob);
1.51 markus 666:
1.106 deraadt 667: /* try another method if we did not send a packet */
1.278 markus 668: if (r == 0 && sent == 0)
1.295 djm 669: userauth(ssh, NULL);
1.278 markus 670: return r;
1.20 markus 671: }
1.121 markus 672:
673: #ifdef GSSAPI
1.133 djm 674: int
1.295 djm 675: userauth_gssapi(struct ssh *ssh)
1.121 markus 676: {
1.295 djm 677: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.121 markus 678: Gssctxt *gssctxt = NULL;
1.128 avsm 679: static gss_OID_set gss_supported = NULL;
1.139 djm 680: static u_int mech = 0;
1.121 markus 681: OM_uint32 min;
1.278 markus 682: int r, ok = 0;
1.121 markus 683:
684: /* Try one GSSAPI method at a time, rather than sending them all at
685: * once. */
686:
1.128 avsm 687: if (gss_supported == NULL)
688: gss_indicate_mechs(&min, &gss_supported);
1.121 markus 689:
690: /* Check to see if the mechanism is usable before we offer it */
1.128 avsm 691: while (mech < gss_supported->count && !ok) {
1.121 markus 692: /* My DER encoding requires length<128 */
1.128 avsm 693: if (gss_supported->elements[mech].length < 128 &&
1.271 djm 694: ssh_gssapi_check_mechanism(&gssctxt,
1.161 djm 695: &gss_supported->elements[mech], authctxt->host)) {
1.121 markus 696: ok = 1; /* Mechanism works */
697: } else {
698: mech++;
699: }
700: }
701:
1.161 djm 702: if (!ok)
1.139 djm 703: return 0;
1.121 markus 704:
705: authctxt->methoddata=(void *)gssctxt;
706:
1.278 markus 707: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
708: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
709: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
710: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
711: (r = sshpkt_put_u32(ssh, 1)) != 0 ||
712: (r = sshpkt_put_u32(ssh,
713: (gss_supported->elements[mech].length) + 2)) != 0 ||
714: (r = sshpkt_put_u8(ssh, SSH_GSS_OIDTYPE)) != 0 ||
715: (r = sshpkt_put_u8(ssh,
716: gss_supported->elements[mech].length)) != 0 ||
717: (r = sshpkt_put(ssh,
718: gss_supported->elements[mech].elements,
719: gss_supported->elements[mech].length)) != 0 ||
720: (r = sshpkt_send(ssh)) != 0)
721: fatal("%s: %s", __func__, ssh_err(r));
722:
723: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_RESPONSE, &input_gssapi_response);
724: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_TOKEN, &input_gssapi_token);
725: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_ERROR, &input_gssapi_error);
726: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_ERRTOK, &input_gssapi_errtok);
1.121 markus 727:
728: mech++; /* Move along to next candidate */
729:
730: return 1;
731: }
732:
1.130 markus 733: static OM_uint32
1.262 djm 734: process_gssapi_token(struct ssh *ssh, gss_buffer_t recv_tok)
1.130 markus 735: {
1.260 markus 736: Authctxt *authctxt = ssh->authctxt;
1.130 markus 737: Gssctxt *gssctxt = authctxt->methoddata;
738: gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
1.142 djm 739: gss_buffer_desc mic = GSS_C_EMPTY_BUFFER;
740: gss_buffer_desc gssbuf;
1.132 markus 741: OM_uint32 status, ms, flags;
1.278 markus 742: int r;
1.133 djm 743:
1.130 markus 744: status = ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
1.132 markus 745: recv_tok, &send_tok, &flags);
1.130 markus 746:
747: if (send_tok.length > 0) {
1.278 markus 748: u_char type = GSS_ERROR(status) ?
749: SSH2_MSG_USERAUTH_GSSAPI_ERRTOK :
750: SSH2_MSG_USERAUTH_GSSAPI_TOKEN;
751:
752: if ((r = sshpkt_start(ssh, type)) != 0 ||
753: (r = sshpkt_put_string(ssh, send_tok.value,
754: send_tok.length)) != 0 ||
755: (r = sshpkt_send(ssh)) != 0)
756: fatal("%s: %s", __func__, ssh_err(r));
1.133 djm 757:
1.130 markus 758: gss_release_buffer(&ms, &send_tok);
759: }
1.133 djm 760:
1.130 markus 761: if (status == GSS_S_COMPLETE) {
1.132 markus 762: /* send either complete or MIC, depending on mechanism */
763: if (!(flags & GSS_C_INTEG_FLAG)) {
1.278 markus 764: if ((r = sshpkt_start(ssh,
765: SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE)) != 0 ||
766: (r = sshpkt_send(ssh)) != 0)
767: fatal("%s: %s", __func__, ssh_err(r));
1.132 markus 768: } else {
1.278 markus 769: struct sshbuf *b;
770:
771: if ((b = sshbuf_new()) == NULL)
772: fatal("%s: sshbuf_new failed", __func__);
773: ssh_gssapi_buildmic(b, authctxt->server_user,
1.132 markus 774: authctxt->service, "gssapi-with-mic");
775:
1.278 markus 776: if ((gssbuf.value = sshbuf_mutable_ptr(b)) == NULL)
777: fatal("%s: sshbuf_mutable_ptr failed", __func__);
778: gssbuf.length = sshbuf_len(b);
1.133 djm 779:
1.132 markus 780: status = ssh_gssapi_sign(gssctxt, &gssbuf, &mic);
1.133 djm 781:
1.132 markus 782: if (!GSS_ERROR(status)) {
1.278 markus 783: if ((r = sshpkt_start(ssh,
784: SSH2_MSG_USERAUTH_GSSAPI_MIC)) != 0 ||
785: (r = sshpkt_put_string(ssh, mic.value,
786: mic.length)) != 0 ||
787: (r = sshpkt_send(ssh)) != 0)
788: fatal("%s: %s", __func__, ssh_err(r));
1.132 markus 789: }
1.133 djm 790:
1.278 markus 791: sshbuf_free(b);
1.132 markus 792: gss_release_buffer(&ms, &mic);
1.133 djm 793: }
1.130 markus 794: }
1.133 djm 795:
1.130 markus 796: return status;
797: }
798:
1.169 djm 799: /* ARGSUSED */
1.220 djm 800: int
1.261 markus 801: input_gssapi_response(int type, u_int32_t plen, struct ssh *ssh)
1.121 markus 802: {
1.260 markus 803: Authctxt *authctxt = ssh->authctxt;
1.121 markus 804: Gssctxt *gssctxt;
1.278 markus 805: size_t oidlen;
806: u_char *oidv = NULL;
807: int r;
1.121 markus 808:
809: if (authctxt == NULL)
810: fatal("input_gssapi_response: no authentication context");
811: gssctxt = authctxt->methoddata;
812:
813: /* Setup our OID */
1.278 markus 814: if ((r = sshpkt_get_string(ssh, &oidv, &oidlen)) != 0)
815: goto done;
1.121 markus 816:
1.129 markus 817: if (oidlen <= 2 ||
818: oidv[0] != SSH_GSS_OIDTYPE ||
819: oidv[1] != oidlen - 2) {
820: debug("Badly encoded mechanism OID received");
1.296 ! djm 821: userauth(ssh, NULL);
1.278 markus 822: goto ok;
1.121 markus 823: }
1.129 markus 824:
825: if (!ssh_gssapi_check_oid(gssctxt, oidv + 2, oidlen - 2))
826: fatal("Server returned different OID than expected");
1.121 markus 827:
1.278 markus 828: if ((r = sshpkt_get_end(ssh)) != 0)
829: goto done;
1.121 markus 830:
1.262 djm 831: if (GSS_ERROR(process_gssapi_token(ssh, GSS_C_NO_BUFFER))) {
1.121 markus 832: /* Start again with next method on list */
833: debug("Trying to start again");
1.296 ! djm 834: userauth(ssh, NULL);
1.278 markus 835: goto ok;
1.121 markus 836: }
1.278 markus 837: ok:
838: r = 0;
839: done:
840: free(oidv);
841: return r;
1.121 markus 842: }
843:
1.169 djm 844: /* ARGSUSED */
1.220 djm 845: int
1.261 markus 846: input_gssapi_token(int type, u_int32_t plen, struct ssh *ssh)
1.121 markus 847: {
1.260 markus 848: Authctxt *authctxt = ssh->authctxt;
1.121 markus 849: gss_buffer_desc recv_tok;
1.278 markus 850: u_char *p = NULL;
851: size_t len;
1.130 markus 852: OM_uint32 status;
1.278 markus 853: int r;
1.121 markus 854:
855: if (authctxt == NULL)
856: fatal("input_gssapi_response: no authentication context");
857:
1.278 markus 858: if ((r = sshpkt_get_string(ssh, &p, &len)) != 0 ||
859: (r = sshpkt_get_end(ssh)) != 0)
860: goto out;
1.121 markus 861:
1.278 markus 862: recv_tok.value = p;
863: recv_tok.length = len;
1.262 djm 864: status = process_gssapi_token(ssh, &recv_tok);
1.121 markus 865:
1.278 markus 866: /* Start again with the next method in the list */
1.121 markus 867: if (GSS_ERROR(status)) {
1.296 ! djm 868: userauth(ssh, NULL);
1.278 markus 869: /* ok */
1.121 markus 870: }
1.278 markus 871: r = 0;
872: out:
873: free(p);
874: return r;
1.121 markus 875: }
876:
1.169 djm 877: /* ARGSUSED */
1.220 djm 878: int
1.261 markus 879: input_gssapi_errtok(int type, u_int32_t plen, struct ssh *ssh)
1.121 markus 880: {
1.260 markus 881: Authctxt *authctxt = ssh->authctxt;
1.121 markus 882: Gssctxt *gssctxt;
883: gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
884: gss_buffer_desc recv_tok;
1.194 djm 885: OM_uint32 ms;
1.278 markus 886: u_char *p = NULL;
887: size_t len;
888: int r;
1.121 markus 889:
890: if (authctxt == NULL)
891: fatal("input_gssapi_response: no authentication context");
892: gssctxt = authctxt->methoddata;
893:
1.278 markus 894: if ((r = sshpkt_get_string(ssh, &p, &len)) != 0 ||
895: (r = sshpkt_get_end(ssh)) != 0) {
896: free(p);
897: return r;
898: }
1.121 markus 899:
900: /* Stick it into GSSAPI and see what it says */
1.278 markus 901: recv_tok.value = p;
902: recv_tok.length = len;
1.194 djm 903: (void)ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
1.140 djm 904: &recv_tok, &send_tok, NULL);
1.278 markus 905: free(p);
1.121 markus 906: gss_release_buffer(&ms, &send_tok);
907:
908: /* Server will be returning a failed packet after this one */
1.220 djm 909: return 0;
1.121 markus 910: }
911:
1.169 djm 912: /* ARGSUSED */
1.220 djm 913: int
1.261 markus 914: input_gssapi_error(int type, u_int32_t plen, struct ssh *ssh)
1.121 markus 915: {
1.278 markus 916: char *msg = NULL;
917: char *lang = NULL;
918: int r;
1.121 markus 919:
1.278 markus 920: if ((r = sshpkt_get_u32(ssh, NULL)) != 0 || /* maj */
921: (r = sshpkt_get_u32(ssh, NULL)) != 0 || /* min */
922: (r = sshpkt_get_cstring(ssh, &msg, NULL)) != 0 ||
923: (r = sshpkt_get_cstring(ssh, &lang, NULL)) != 0)
924: goto out;
925: r = sshpkt_get_end(ssh);
1.143 stevesk 926: debug("Server GSSAPI Error:\n%s", msg);
1.278 markus 927: out:
1.197 djm 928: free(msg);
929: free(lang);
1.278 markus 930: return r;
1.121 markus 931: }
932: #endif /* GSSAPI */
1.20 markus 933:
1.1 markus 934: int
1.295 djm 935: userauth_none(struct ssh *ssh)
1.23 markus 936: {
1.295 djm 937: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.278 markus 938: int r;
939:
1.23 markus 940: /* initial userauth request */
1.278 markus 941: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
942: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
943: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
944: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
945: (r = sshpkt_send(ssh)) != 0)
946: fatal("%s: %s", __func__, ssh_err(r));
1.23 markus 947: return 1;
948: }
949:
950: int
1.295 djm 951: userauth_passwd(struct ssh *ssh)
1.1 markus 952: {
1.295 djm 953: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.290 djm 954: char *password, *prompt = NULL;
1.175 dtucker 955: const char *host = options.host_key_alias ? options.host_key_alias :
956: authctxt->host;
1.278 markus 957: int r;
1.6 markus 958:
1.292 djm 959: if (authctxt->attempt_passwd++ >= options.number_of_password_prompts)
1.6 markus 960: return 0;
1.13 todd 961:
1.292 djm 962: if (authctxt->attempt_passwd != 1)
1.13 todd 963: error("Permission denied, please try again.");
1.1 markus 964:
1.290 djm 965: xasprintf(&prompt, "%s@%s's password: ", authctxt->server_user, host);
1.1 markus 966: password = read_passphrase(prompt, 0);
1.278 markus 967: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
968: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
969: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
970: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
971: (r = sshpkt_put_u8(ssh, 0)) != 0 ||
972: (r = sshpkt_put_cstring(ssh, password)) != 0 ||
973: (r = sshpkt_add_padding(ssh, 64)) != 0 ||
974: (r = sshpkt_send(ssh)) != 0)
975: fatal("%s: %s", __func__, ssh_err(r));
1.99 markus 976:
1.290 djm 977: free(prompt);
978: if (password != NULL)
1.278 markus 979: freezero(password, strlen(password));
980:
981: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
1.99 markus 982: &input_userauth_passwd_changereq);
983:
1.1 markus 984: return 1;
985: }
1.169 djm 986:
1.99 markus 987: /*
988: * parse PASSWD_CHANGEREQ, prompt user and send SSH2_MSG_USERAUTH_REQUEST
989: */
1.169 djm 990: /* ARGSUSED */
1.218 markus 991: int
1.261 markus 992: input_userauth_passwd_changereq(int type, u_int32_t seqnr, struct ssh *ssh)
1.99 markus 993: {
1.260 markus 994: Authctxt *authctxt = ssh->authctxt;
1.278 markus 995: char *info = NULL, *lang = NULL, *password = NULL, *retype = NULL;
1.266 dtucker 996: char prompt[256];
1.252 djm 997: const char *host;
1.278 markus 998: int r;
1.99 markus 999:
1000: debug2("input_userauth_passwd_changereq");
1001:
1002: if (authctxt == NULL)
1003: fatal("input_userauth_passwd_changereq: "
1004: "no authentication context");
1.252 djm 1005: host = options.host_key_alias ? options.host_key_alias : authctxt->host;
1.99 markus 1006:
1.278 markus 1007: if ((r = sshpkt_get_cstring(ssh, &info, NULL)) != 0 ||
1008: (r = sshpkt_get_cstring(ssh, &lang, NULL)) != 0)
1009: goto out;
1.99 markus 1010: if (strlen(info) > 0)
1.116 itojun 1011: logit("%s", info);
1.278 markus 1012: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1013: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1014: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1015: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1016: (r = sshpkt_put_u8(ssh, 1)) != 0) /* additional info */
1017: goto out;
1018:
1.104 deraadt 1019: snprintf(prompt, sizeof(prompt),
1.99 markus 1020: "Enter %.30s@%.128s's old password: ",
1.175 dtucker 1021: authctxt->server_user, host);
1.99 markus 1022: password = read_passphrase(prompt, 0);
1.278 markus 1023: if ((r = sshpkt_put_cstring(ssh, password)) != 0)
1024: goto out;
1025:
1026: freezero(password, strlen(password));
1.99 markus 1027: password = NULL;
1028: while (password == NULL) {
1.104 deraadt 1029: snprintf(prompt, sizeof(prompt),
1.99 markus 1030: "Enter %.30s@%.128s's new password: ",
1.175 dtucker 1031: authctxt->server_user, host);
1.99 markus 1032: password = read_passphrase(prompt, RP_ALLOW_EOF);
1033: if (password == NULL) {
1034: /* bail out */
1.278 markus 1035: r = 0;
1036: goto out;
1.99 markus 1037: }
1.104 deraadt 1038: snprintf(prompt, sizeof(prompt),
1.99 markus 1039: "Retype %.30s@%.128s's new password: ",
1.175 dtucker 1040: authctxt->server_user, host);
1.99 markus 1041: retype = read_passphrase(prompt, 0);
1042: if (strcmp(password, retype) != 0) {
1.278 markus 1043: freezero(password, strlen(password));
1.116 itojun 1044: logit("Mismatch; try again, EOF to quit.");
1.99 markus 1045: password = NULL;
1046: }
1.278 markus 1047: freezero(retype, strlen(retype));
1.99 markus 1048: }
1.278 markus 1049: if ((r = sshpkt_put_cstring(ssh, password)) != 0 ||
1050: (r = sshpkt_add_padding(ssh, 64)) != 0 ||
1051: (r = sshpkt_send(ssh)) != 0)
1052: goto out;
1.104 deraadt 1053:
1.278 markus 1054: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
1.99 markus 1055: &input_userauth_passwd_changereq);
1.278 markus 1056: r = 0;
1057: out:
1058: if (password)
1059: freezero(password, strlen(password));
1060: free(info);
1061: free(lang);
1062: return r;
1.117 markus 1063: }
1064:
1.272 djm 1065: /*
1066: * Select an algorithm for publickey signatures.
1067: * Returns algorithm (caller must free) or NULL if no mutual algorithm found.
1068: *
1069: * Call with ssh==NULL to ignore server-sig-algs extension list and
1070: * only attempt with the key's base signature type.
1071: */
1072: static char *
1073: key_sig_algorithm(struct ssh *ssh, const struct sshkey *key)
1.231 markus 1074: {
1.274 djm 1075: char *allowed, *oallowed, *cp, *tmp, *alg = NULL;
1.231 markus 1076:
1.272 djm 1077: /*
1078: * The signature algorithm will only differ from the key algorithm
1079: * for RSA keys/certs and when the server advertises support for
1080: * newer (SHA2) algorithms.
1081: */
1082: if (ssh == NULL || ssh->kex->server_sig_algs == NULL ||
1.288 djm 1083: (key->type != KEY_RSA && key->type != KEY_RSA_CERT) ||
1084: (key->type == KEY_RSA_CERT && (datafellows & SSH_BUG_SIGTYPE))) {
1.272 djm 1085: /* Filter base key signature alg against our configuration */
1.279 markus 1086: return match_list(sshkey_ssh_name(key),
1.272 djm 1087: options.pubkey_key_types, NULL);
1.231 markus 1088: }
1089:
1.272 djm 1090: /*
1091: * For RSA keys/certs, since these might have a different sig type:
1092: * find the first entry in PubkeyAcceptedKeyTypes of the right type
1093: * that also appears in the supported signature algorithms list from
1094: * the server.
1095: */
1096: oallowed = allowed = xstrdup(options.pubkey_key_types);
1097: while ((cp = strsep(&allowed, ",")) != NULL) {
1098: if (sshkey_type_from_name(cp) != key->type)
1099: continue;
1.274 djm 1100: tmp = match_list(sshkey_sigalg_by_name(cp), ssh->kex->server_sig_algs, NULL);
1101: if (tmp != NULL)
1102: alg = xstrdup(cp);
1103: free(tmp);
1.272 djm 1104: if (alg != NULL)
1105: break;
1.269 djm 1106: }
1.272 djm 1107: free(oallowed);
1108: return alg;
1.269 djm 1109: }
1110:
1.117 markus 1111: static int
1.214 djm 1112: identity_sign(struct identity *id, u_char **sigp, size_t *lenp,
1.272 djm 1113: const u_char *data, size_t datalen, u_int compat, const char *alg)
1.117 markus 1114: {
1.259 markus 1115: struct sshkey *prv;
1.269 djm 1116: int r;
1.99 markus 1117:
1.272 djm 1118: /* The agent supports this key. */
1.269 djm 1119: if (id->key != NULL && id->agent_fd != -1) {
1.272 djm 1120: return ssh_agent_sign(id->agent_fd, id->key, sigp, lenp,
1121: data, datalen, alg, compat);
1.269 djm 1122: }
1.214 djm 1123:
1.117 markus 1124: /*
1.272 djm 1125: * We have already loaded the private key or the private key is
1126: * stored in external hardware.
1.117 markus 1127: */
1.255 djm 1128: if (id->key != NULL &&
1.272 djm 1129: (id->isprivate || (id->key->flags & SSHKEY_FLAG_EXT))) {
1130: if ((r = sshkey_sign(id->key, sigp, lenp, data, datalen,
1131: alg, compat)) != 0)
1132: return r;
1133: /*
1134: * PKCS#11 tokens may not support all signature algorithms,
1135: * so check what we get back.
1136: */
1137: if ((r = sshkey_check_sigtype(*sigp, *lenp, alg)) != 0)
1138: return r;
1139: return 0;
1140: }
1.255 djm 1141:
1.272 djm 1142: /* Load the private key from the file. */
1.229 jcs 1143: if ((prv = load_identity_file(id)) == NULL)
1.239 djm 1144: return SSH_ERR_KEY_NOT_FOUND;
1.265 djm 1145: if (id->key != NULL && !sshkey_equal_public(prv, id->key)) {
1146: error("%s: private key %s contents do not match public",
1147: __func__, id->filename);
1148: return SSH_ERR_KEY_NOT_FOUND;
1149: }
1.272 djm 1150: r = sshkey_sign(prv, sigp, lenp, data, datalen, alg, compat);
1.214 djm 1151: sshkey_free(prv);
1.269 djm 1152: return r;
1.51 markus 1153: }
1154:
1.76 itojun 1155: static int
1.255 djm 1156: id_filename_matches(Identity *id, Identity *private_id)
1157: {
1158: const char *suffixes[] = { ".pub", "-cert.pub", NULL };
1159: size_t len = strlen(id->filename), plen = strlen(private_id->filename);
1160: size_t i, slen;
1161:
1162: if (strcmp(id->filename, private_id->filename) == 0)
1163: return 1;
1164: for (i = 0; suffixes[i]; i++) {
1165: slen = strlen(suffixes[i]);
1166: if (len > slen && plen == len - slen &&
1167: strcmp(id->filename + (len - slen), suffixes[i]) == 0 &&
1168: memcmp(id->filename, private_id->filename, plen) == 0)
1169: return 1;
1170: }
1171: return 0;
1172: }
1173:
1174: static int
1.295 djm 1175: sign_and_send_pubkey(struct ssh *ssh, Identity *id)
1.1 markus 1176: {
1.295 djm 1177: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.272 djm 1178: struct sshbuf *b = NULL;
1179: Identity *private_id, *sign_id = NULL;
1180: u_char *signature = NULL;
1181: size_t slen = 0, skip = 0;
1182: int r, fallback_sigtype, sent = 0;
1183: char *alg = NULL, *fp = NULL;
1184: const char *loc = "";
1.1 markus 1185:
1.222 djm 1186: if ((fp = sshkey_fingerprint(id->key, options.fingerprint_hash,
1187: SSH_FP_DEFAULT)) == NULL)
1188: return 0;
1.51 markus 1189:
1.272 djm 1190: debug3("%s: %s %s", __func__, sshkey_type(id->key), fp);
1.1 markus 1191:
1.227 djm 1192: /*
1193: * If the key is an certificate, try to find a matching private key
1194: * and use it to complete the signature.
1.241 djm 1195: * If no such private key exists, fall back to trying the certificate
1196: * key itself in case it has a private half already loaded.
1.272 djm 1197: * This will try to set sign_id to the private key that will perform
1198: * the signature.
1.227 djm 1199: */
1.272 djm 1200: if (sshkey_is_cert(id->key)) {
1.227 djm 1201: TAILQ_FOREACH(private_id, &authctxt->keys, next) {
1202: if (sshkey_equal_public(id->key, private_id->key) &&
1203: id->key->type != private_id->key->type) {
1.272 djm 1204: sign_id = private_id;
1.227 djm 1205: break;
1206: }
1207: }
1.255 djm 1208: /*
1209: * Exact key matches are preferred, but also allow
1210: * filename matches for non-PKCS#11/agent keys that
1211: * didn't load public keys. This supports the case
1212: * of keeping just a private key file and public
1213: * certificate on disk.
1214: */
1.272 djm 1215: if (sign_id == NULL &&
1216: !id->isprivate && id->agent_fd == -1 &&
1.255 djm 1217: (id->key->flags & SSHKEY_FLAG_EXT) == 0) {
1218: TAILQ_FOREACH(private_id, &authctxt->keys, next) {
1219: if (private_id->key == NULL &&
1220: id_filename_matches(id, private_id)) {
1.272 djm 1221: sign_id = private_id;
1.255 djm 1222: break;
1223: }
1224: }
1225: }
1.272 djm 1226: if (sign_id != NULL) {
1.227 djm 1227: debug2("%s: using private key \"%s\"%s for "
1228: "certificate", __func__, id->filename,
1229: id->agent_fd != -1 ? " from agent" : "");
1230: } else {
1.240 djm 1231: debug("%s: no separate private key for certificate "
1.227 djm 1232: "\"%s\"", __func__, id->filename);
1233: }
1234: }
1235:
1.272 djm 1236: /*
1237: * If the above didn't select another identity to do the signing
1238: * then default to the one we started with.
1239: */
1240: if (sign_id == NULL)
1241: sign_id = id;
1242:
1243: /* assemble and sign data */
1244: for (fallback_sigtype = 0; fallback_sigtype <= 1; fallback_sigtype++) {
1245: free(alg);
1246: slen = 0;
1247: signature = NULL;
1248: if ((alg = key_sig_algorithm(fallback_sigtype ? NULL : ssh,
1249: id->key)) == NULL) {
1250: error("%s: no mutual signature supported", __func__);
1251: goto out;
1252: }
1253: debug3("%s: signing using %s", __func__, alg);
1254:
1255: sshbuf_free(b);
1256: if ((b = sshbuf_new()) == NULL)
1257: fatal("%s: sshbuf_new failed", __func__);
1258: if (datafellows & SSH_OLD_SESSIONID) {
1259: if ((r = sshbuf_put(b, session_id2,
1260: session_id2_len)) != 0) {
1261: fatal("%s: sshbuf_put: %s",
1262: __func__, ssh_err(r));
1263: }
1264: } else {
1265: if ((r = sshbuf_put_string(b, session_id2,
1266: session_id2_len)) != 0) {
1267: fatal("%s: sshbuf_put_string: %s",
1268: __func__, ssh_err(r));
1269: }
1270: }
1.278 markus 1271: skip = sshbuf_len(b);
1.272 djm 1272: if ((r = sshbuf_put_u8(b, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1273: (r = sshbuf_put_cstring(b, authctxt->server_user)) != 0 ||
1274: (r = sshbuf_put_cstring(b, authctxt->service)) != 0 ||
1275: (r = sshbuf_put_cstring(b, authctxt->method->name)) != 0 ||
1276: (r = sshbuf_put_u8(b, 1)) != 0 ||
1277: (r = sshbuf_put_cstring(b, alg)) != 0 ||
1278: (r = sshkey_puts(id->key, b)) != 0) {
1279: fatal("%s: assemble signed data: %s",
1280: __func__, ssh_err(r));
1281: }
1282:
1283: /* generate signature */
1284: r = identity_sign(sign_id, &signature, &slen,
1285: sshbuf_ptr(b), sshbuf_len(b), datafellows, alg);
1286: if (r == 0)
1287: break;
1288: else if (r == SSH_ERR_KEY_NOT_FOUND)
1289: goto out; /* soft failure */
1290: else if (r == SSH_ERR_SIGN_ALG_UNSUPPORTED &&
1291: !fallback_sigtype) {
1292: if (sign_id->agent_fd != -1)
1293: loc = "agent ";
1294: else if ((sign_id->key->flags & SSHKEY_FLAG_EXT) != 0)
1295: loc = "token ";
1296: logit("%skey %s %s returned incorrect signature type",
1297: loc, sshkey_type(id->key), fp);
1298: continue;
1299: }
1300: error("%s: signing failed: %s", __func__, ssh_err(r));
1301: goto out;
1.17 markus 1302: }
1.272 djm 1303: if (slen == 0 || signature == NULL) /* shouldn't happen */
1304: fatal("%s: no signature", __func__);
1.51 markus 1305:
1.1 markus 1306: /* append signature */
1.272 djm 1307: if ((r = sshbuf_put_string(b, signature, slen)) != 0)
1308: fatal("%s: append signature: %s", __func__, ssh_err(r));
1.1 markus 1309:
1.272 djm 1310: #ifdef DEBUG_PK
1311: sshbuf_dump(b, stderr);
1312: #endif
1.1 markus 1313: /* skip session id and packet type */
1.272 djm 1314: if ((r = sshbuf_consume(b, skip + 1)) != 0)
1315: fatal("%s: consume: %s", __func__, ssh_err(r));
1.1 markus 1316:
1317: /* put remaining data from buffer into packet */
1.272 djm 1318: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1319: (r = sshpkt_putb(ssh, b)) != 0 ||
1320: (r = sshpkt_send(ssh)) != 0)
1321: fatal("%s: enqueue request: %s", __func__, ssh_err(r));
1322:
1323: /* success */
1324: sent = 1;
1.17 markus 1325:
1.272 djm 1326: out:
1327: free(fp);
1328: free(alg);
1329: sshbuf_free(b);
1330: freezero(signature, slen);
1331: return sent;
1.16 markus 1332: }
1333:
1.76 itojun 1334: static int
1.295 djm 1335: send_pubkey_test(struct ssh *ssh, Identity *id)
1.20 markus 1336: {
1.295 djm 1337: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.272 djm 1338: u_char *blob = NULL;
1339: char *alg = NULL;
1.278 markus 1340: size_t bloblen;
1341: u_int have_sig = 0;
1342: int sent = 0, r;
1.20 markus 1343:
1.272 djm 1344: if ((alg = key_sig_algorithm(ssh, id->key)) == NULL) {
1345: debug("%s: no mutual signature algorithm", __func__);
1346: goto out;
1347: }
1.16 markus 1348:
1.278 markus 1349: if ((r = sshkey_to_blob(id->key, &blob, &bloblen)) != 0) {
1.51 markus 1350: /* we cannot handle this key */
1.272 djm 1351: debug3("%s: cannot handle key", __func__);
1352: goto out;
1.16 markus 1353: }
1.51 markus 1354: /* register callback for USERAUTH_PK_OK message */
1.278 markus 1355: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_PK_OK, &input_userauth_pk_ok);
1.51 markus 1356:
1.278 markus 1357: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1358: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1359: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1360: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1361: (r = sshpkt_put_u8(ssh, have_sig)) != 0 ||
1362: (r = sshpkt_put_cstring(ssh, alg)) != 0 ||
1363: (r = sshpkt_put_string(ssh, blob, bloblen)) != 0 ||
1364: (r = sshpkt_send(ssh)) != 0)
1365: fatal("%s: %s", __func__, ssh_err(r));
1.272 djm 1366: sent = 1;
1.278 markus 1367:
1368: out:
1.272 djm 1369: free(alg);
1.197 djm 1370: free(blob);
1.272 djm 1371: return sent;
1.51 markus 1372: }
1373:
1.259 markus 1374: static struct sshkey *
1.229 jcs 1375: load_identity_file(Identity *id)
1.51 markus 1376: {
1.259 markus 1377: struct sshkey *private = NULL;
1.229 jcs 1378: char prompt[300], *passphrase, *comment;
1.215 djm 1379: int r, perm_ok = 0, quit = 0, i;
1.52 markus 1380: struct stat st;
1.16 markus 1381:
1.229 jcs 1382: if (stat(id->filename, &st) < 0) {
1383: (id->userprovided ? logit : debug3)("no such identity: %s: %s",
1384: id->filename, strerror(errno));
1.52 markus 1385: return NULL;
1386: }
1.214 djm 1387: snprintf(prompt, sizeof prompt,
1.229 jcs 1388: "Enter passphrase for key '%.100s': ", id->filename);
1.214 djm 1389: for (i = 0; i <= options.number_of_password_prompts; i++) {
1390: if (i == 0)
1391: passphrase = "";
1392: else {
1.20 markus 1393: passphrase = read_passphrase(prompt, 0);
1.214 djm 1394: if (*passphrase == '\0') {
1.20 markus 1395: debug2("no passphrase given, try next key");
1.214 djm 1396: free(passphrase);
1397: break;
1398: }
1399: }
1.229 jcs 1400: switch ((r = sshkey_load_private_type(KEY_UNSPEC, id->filename,
1401: passphrase, &private, &comment, &perm_ok))) {
1.214 djm 1402: case 0:
1403: break;
1404: case SSH_ERR_KEY_WRONG_PASSPHRASE:
1405: if (options.batch_mode) {
1406: quit = 1;
1407: break;
1408: }
1.215 djm 1409: if (i != 0)
1410: debug2("bad passphrase given, try again...");
1.214 djm 1411: break;
1412: case SSH_ERR_SYSTEM_ERROR:
1413: if (errno == ENOENT) {
1414: debug2("Load key \"%s\": %s",
1.229 jcs 1415: id->filename, ssh_err(r));
1.51 markus 1416: quit = 1;
1.214 djm 1417: break;
1.20 markus 1418: }
1.214 djm 1419: /* FALLTHROUGH */
1420: default:
1.229 jcs 1421: error("Load key \"%s\": %s", id->filename, ssh_err(r));
1.214 djm 1422: quit = 1;
1423: break;
1424: }
1.230 djm 1425: if (!quit && private != NULL && id->agent_fd == -1 &&
1.229 jcs 1426: !(id->key && id->isprivate))
1427: maybe_add_key_to_agent(id->filename, private, comment,
1428: passphrase);
1.278 markus 1429: if (i > 0)
1430: freezero(passphrase, strlen(passphrase));
1.232 mmcc 1431: free(comment);
1.214 djm 1432: if (private != NULL || quit)
1433: break;
1.16 markus 1434: }
1.51 markus 1435: return private;
1436: }
1437:
1.272 djm 1438: static int
1439: key_type_allowed_by_config(struct sshkey *key)
1440: {
1441: if (match_pattern_list(sshkey_ssh_name(key),
1442: options.pubkey_key_types, 0) == 1)
1443: return 1;
1444:
1445: /* RSA keys/certs might be allowed by alternate signature types */
1446: switch (key->type) {
1447: case KEY_RSA:
1448: if (match_pattern_list("rsa-sha2-512",
1449: options.pubkey_key_types, 0) == 1)
1450: return 1;
1451: if (match_pattern_list("rsa-sha2-256",
1452: options.pubkey_key_types, 0) == 1)
1453: return 1;
1454: break;
1455: case KEY_RSA_CERT:
1456: if (match_pattern_list("rsa-sha2-512-cert-v01@openssh.com",
1457: options.pubkey_key_types, 0) == 1)
1458: return 1;
1459: if (match_pattern_list("rsa-sha2-256-cert-v01@openssh.com",
1460: options.pubkey_key_types, 0) == 1)
1461: return 1;
1462: break;
1463: }
1464: return 0;
1465: }
1466:
1467:
1.117 markus 1468: /*
1469: * try keys in the following order:
1.227 djm 1470: * 1. certificates listed in the config file
1471: * 2. other input certificates
1472: * 3. agent keys that are found in the config file
1473: * 4. other agent keys
1474: * 5. keys that are only listed in the config file
1.117 markus 1475: */
1476: static void
1477: pubkey_prepare(Authctxt *authctxt)
1.51 markus 1478: {
1.214 djm 1479: struct identity *id, *id2, *tmp;
1480: struct idlist agent, files, *preferred;
1481: struct sshkey *key;
1.230 djm 1482: int agent_fd = -1, i, r, found;
1.214 djm 1483: size_t j;
1484: struct ssh_identitylist *idlist;
1.287 djm 1485: char *ident;
1.51 markus 1486:
1.117 markus 1487: TAILQ_INIT(&agent); /* keys from the agent */
1488: TAILQ_INIT(&files); /* keys from the config file */
1489: preferred = &authctxt->keys;
1490: TAILQ_INIT(preferred); /* preferred order of keys */
1491:
1.190 djm 1492: /* list of keys stored in the filesystem and PKCS#11 */
1.117 markus 1493: for (i = 0; i < options.num_identity_files; i++) {
1494: key = options.identity_keys[i];
1.180 djm 1495: if (key && key->cert && key->cert->type != SSH2_CERT_TYPE_USER)
1.117 markus 1496: continue;
1497: options.identity_keys[i] = NULL;
1.150 djm 1498: id = xcalloc(1, sizeof(*id));
1.230 djm 1499: id->agent_fd = -1;
1.117 markus 1500: id->key = key;
1501: id->filename = xstrdup(options.identity_files[i]);
1.192 dtucker 1502: id->userprovided = options.identity_file_userprovided[i];
1.117 markus 1503: TAILQ_INSERT_TAIL(&files, id, next);
1.190 djm 1504: }
1.227 djm 1505: /* list of certificates specified by user */
1506: for (i = 0; i < options.num_certificate_files; i++) {
1507: key = options.certificates[i];
1.278 markus 1508: if (!sshkey_is_cert(key) || key->cert == NULL ||
1.227 djm 1509: key->cert->type != SSH2_CERT_TYPE_USER)
1510: continue;
1511: id = xcalloc(1, sizeof(*id));
1.230 djm 1512: id->agent_fd = -1;
1.227 djm 1513: id->key = key;
1514: id->filename = xstrdup(options.certificate_files[i]);
1515: id->userprovided = options.certificate_file_userprovided[i];
1516: TAILQ_INSERT_TAIL(preferred, id, next);
1.117 markus 1517: }
1518: /* list of keys supported by the agent */
1.214 djm 1519: if ((r = ssh_get_authentication_socket(&agent_fd)) != 0) {
1520: if (r != SSH_ERR_AGENT_NOT_PRESENT)
1521: debug("%s: ssh_get_authentication_socket: %s",
1522: __func__, ssh_err(r));
1.258 naddy 1523: } else if ((r = ssh_fetch_identitylist(agent_fd, &idlist)) != 0) {
1.214 djm 1524: if (r != SSH_ERR_AGENT_NO_IDENTITIES)
1525: debug("%s: ssh_fetch_identitylist: %s",
1526: __func__, ssh_err(r));
1.237 markus 1527: close(agent_fd);
1.214 djm 1528: } else {
1529: for (j = 0; j < idlist->nkeys; j++) {
1.117 markus 1530: found = 0;
1531: TAILQ_FOREACH(id, &files, next) {
1.214 djm 1532: /*
1533: * agent keys from the config file are
1534: * preferred
1535: */
1536: if (sshkey_equal(idlist->keys[j], id->key)) {
1.117 markus 1537: TAILQ_REMOVE(&files, id, next);
1538: TAILQ_INSERT_TAIL(preferred, id, next);
1.214 djm 1539: id->agent_fd = agent_fd;
1.117 markus 1540: found = 1;
1541: break;
1542: }
1543: }
1.135 markus 1544: if (!found && !options.identities_only) {
1.150 djm 1545: id = xcalloc(1, sizeof(*id));
1.214 djm 1546: /* XXX "steals" key/comment from idlist */
1547: id->key = idlist->keys[j];
1548: id->filename = idlist->comments[j];
1549: idlist->keys[j] = NULL;
1550: idlist->comments[j] = NULL;
1551: id->agent_fd = agent_fd;
1.117 markus 1552: TAILQ_INSERT_TAIL(&agent, id, next);
1553: }
1554: }
1.214 djm 1555: ssh_free_identitylist(idlist);
1.117 markus 1556: /* append remaining agent keys */
1557: for (id = TAILQ_FIRST(&agent); id; id = TAILQ_FIRST(&agent)) {
1558: TAILQ_REMOVE(&agent, id, next);
1559: TAILQ_INSERT_TAIL(preferred, id, next);
1560: }
1.214 djm 1561: authctxt->agent_fd = agent_fd;
1.244 djm 1562: }
1563: /* Prefer PKCS11 keys that are explicitly listed */
1564: TAILQ_FOREACH_SAFE(id, &files, next, tmp) {
1565: if (id->key == NULL || (id->key->flags & SSHKEY_FLAG_EXT) == 0)
1566: continue;
1567: found = 0;
1568: TAILQ_FOREACH(id2, &files, next) {
1569: if (id2->key == NULL ||
1570: (id2->key->flags & SSHKEY_FLAG_EXT) == 0)
1571: continue;
1572: if (sshkey_equal(id->key, id2->key)) {
1573: TAILQ_REMOVE(&files, id, next);
1574: TAILQ_INSERT_TAIL(preferred, id, next);
1575: found = 1;
1576: break;
1577: }
1578: }
1579: /* If IdentitiesOnly set and key not found then don't use it */
1580: if (!found && options.identities_only) {
1581: TAILQ_REMOVE(&files, id, next);
1.278 markus 1582: freezero(id, sizeof(*id));
1.244 djm 1583: }
1.117 markus 1584: }
1585: /* append remaining keys from the config file */
1586: for (id = TAILQ_FIRST(&files); id; id = TAILQ_FIRST(&files)) {
1587: TAILQ_REMOVE(&files, id, next);
1588: TAILQ_INSERT_TAIL(preferred, id, next);
1589: }
1.228 djm 1590: /* finally, filter by PubkeyAcceptedKeyTypes */
1591: TAILQ_FOREACH_SAFE(id, preferred, next, id2) {
1.273 djm 1592: if (id->key != NULL && !key_type_allowed_by_config(id->key)) {
1.228 djm 1593: debug("Skipping %s key %s - "
1594: "not in PubkeyAcceptedKeyTypes",
1595: sshkey_ssh_name(id->key), id->filename);
1596: TAILQ_REMOVE(preferred, id, next);
1597: sshkey_free(id->key);
1598: free(id->filename);
1599: memset(id, 0, sizeof(*id));
1600: continue;
1601: }
1.117 markus 1602: }
1.287 djm 1603: /* List the keys we plan on using */
1604: TAILQ_FOREACH_SAFE(id, preferred, next, id2) {
1605: ident = format_identity(id);
1606: debug("Will attempt key: %s", ident);
1607: free(ident);
1608: }
1609: debug2("%s: done", __func__);
1.17 markus 1610: }
1611:
1.117 markus 1612: static void
1613: pubkey_cleanup(Authctxt *authctxt)
1.51 markus 1614: {
1.117 markus 1615: Identity *id;
1.51 markus 1616:
1.289 djm 1617: if (authctxt->agent_fd != -1) {
1.214 djm 1618: ssh_close_authentication_socket(authctxt->agent_fd);
1.289 djm 1619: authctxt->agent_fd = -1;
1620: }
1.117 markus 1621: for (id = TAILQ_FIRST(&authctxt->keys); id;
1622: id = TAILQ_FIRST(&authctxt->keys)) {
1623: TAILQ_REMOVE(&authctxt->keys, id, next);
1.235 mmcc 1624: sshkey_free(id->key);
1.197 djm 1625: free(id->filename);
1626: free(id);
1.117 markus 1627: }
1.1 markus 1628: }
1629:
1.251 djm 1630: static void
1631: pubkey_reset(Authctxt *authctxt)
1632: {
1633: Identity *id;
1634:
1635: TAILQ_FOREACH(id, &authctxt->keys, next)
1636: id->tried = 0;
1637: }
1638:
1.225 markus 1639: static int
1640: try_identity(Identity *id)
1641: {
1642: if (!id->key)
1643: return (0);
1.279 markus 1644: if (sshkey_type_plain(id->key->type) == KEY_RSA &&
1.225 markus 1645: (datafellows & SSH_BUG_RSASIGMD5) != 0) {
1646: debug("Skipped %s key %s for RSA/MD5 server",
1.279 markus 1647: sshkey_type(id->key), id->filename);
1.225 markus 1648: return (0);
1649: }
1.257 djm 1650: return 1;
1.225 markus 1651: }
1652:
1.20 markus 1653: int
1.295 djm 1654: userauth_pubkey(struct ssh *ssh)
1.20 markus 1655: {
1.295 djm 1656: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.117 markus 1657: Identity *id;
1.20 markus 1658: int sent = 0;
1.287 djm 1659: char *ident;
1.20 markus 1660:
1.117 markus 1661: while ((id = TAILQ_FIRST(&authctxt->keys))) {
1662: if (id->tried++)
1663: return (0);
1.127 markus 1664: /* move key to the end of the queue */
1.117 markus 1665: TAILQ_REMOVE(&authctxt->keys, id, next);
1666: TAILQ_INSERT_TAIL(&authctxt->keys, id, next);
1667: /*
1668: * send a test message if we have the public key. for
1669: * encrypted keys we cannot do this and have to load the
1670: * private key instead
1671: */
1.200 djm 1672: if (id->key != NULL) {
1.225 markus 1673: if (try_identity(id)) {
1.287 djm 1674: ident = format_identity(id);
1675: debug("Offering public key: %s", ident);
1676: free(ident);
1.295 djm 1677: sent = send_pubkey_test(ssh, id);
1.200 djm 1678: }
1679: } else {
1.117 markus 1680: debug("Trying private key: %s", id->filename);
1.229 jcs 1681: id->key = load_identity_file(id);
1.117 markus 1682: if (id->key != NULL) {
1.225 markus 1683: if (try_identity(id)) {
1684: id->isprivate = 1;
1.295 djm 1685: sent = sign_and_send_pubkey(ssh, id);
1.200 djm 1686: }
1.278 markus 1687: sshkey_free(id->key);
1.117 markus 1688: id->key = NULL;
1.251 djm 1689: id->isprivate = 0;
1.51 markus 1690: }
1691: }
1.117 markus 1692: if (sent)
1693: return (sent);
1.28 markus 1694: }
1.117 markus 1695: return (0);
1.20 markus 1696: }
1697:
1.23 markus 1698: /*
1699: * Send userauth request message specifying keyboard-interactive method.
1700: */
1701: int
1.295 djm 1702: userauth_kbdint(struct ssh *ssh)
1.23 markus 1703: {
1.295 djm 1704: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.278 markus 1705: int r;
1.23 markus 1706:
1.292 djm 1707: if (authctxt->attempt_kbdint++ >= options.number_of_password_prompts)
1.23 markus 1708: return 0;
1.82 markus 1709: /* disable if no SSH2_MSG_USERAUTH_INFO_REQUEST has been seen */
1.292 djm 1710: if (authctxt->attempt_kbdint > 1 && !authctxt->info_req_seen) {
1.82 markus 1711: debug3("userauth_kbdint: disable: no info_req_seen");
1.278 markus 1712: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_INFO_REQUEST, NULL);
1.82 markus 1713: return 0;
1714: }
1.23 markus 1715:
1716: debug2("userauth_kbdint");
1.278 markus 1717: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1718: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1719: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1720: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1721: (r = sshpkt_put_cstring(ssh, "")) != 0 || /* lang */
1722: (r = sshpkt_put_cstring(ssh, options.kbd_interactive_devices ?
1723: options.kbd_interactive_devices : "")) != 0 ||
1724: (r = sshpkt_send(ssh)) != 0)
1725: fatal("%s: %s", __func__, ssh_err(r));
1.23 markus 1726:
1.278 markus 1727: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_INFO_REQUEST, &input_userauth_info_req);
1.23 markus 1728: return 1;
1729: }
1730:
1731: /*
1.46 markus 1732: * parse INFO_REQUEST, prompt user and send INFO_RESPONSE
1.23 markus 1733: */
1.218 markus 1734: int
1.261 markus 1735: input_userauth_info_req(int type, u_int32_t seq, struct ssh *ssh)
1.23 markus 1736: {
1.260 markus 1737: Authctxt *authctxt = ssh->authctxt;
1.278 markus 1738: char *name = NULL, *inst = NULL, *lang = NULL, *prompt = NULL;
1739: char *response = NULL;
1740: u_char echo = 0;
1.32 markus 1741: u_int num_prompts, i;
1.278 markus 1742: int r;
1.23 markus 1743:
1744: debug2("input_userauth_info_req");
1745:
1746: if (authctxt == NULL)
1747: fatal("input_userauth_info_req: no authentication context");
1.82 markus 1748:
1749: authctxt->info_req_seen = 1;
1.23 markus 1750:
1.278 markus 1751: if ((r = sshpkt_get_cstring(ssh, &name, NULL)) != 0 ||
1752: (r = sshpkt_get_cstring(ssh, &inst, NULL)) != 0 ||
1753: (r = sshpkt_get_cstring(ssh, &lang, NULL)) != 0)
1754: goto out;
1.23 markus 1755: if (strlen(name) > 0)
1.116 itojun 1756: logit("%s", name);
1.23 markus 1757: if (strlen(inst) > 0)
1.116 itojun 1758: logit("%s", inst);
1.23 markus 1759:
1.278 markus 1760: if ((r = sshpkt_get_u32(ssh, &num_prompts)) != 0)
1761: goto out;
1.23 markus 1762: /*
1763: * Begin to build info response packet based on prompts requested.
1764: * We commit to providing the correct number of responses, so if
1765: * further on we run into a problem that prevents this, we have to
1766: * be sure and clean this up and send a correct error response.
1767: */
1.278 markus 1768: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_INFO_RESPONSE)) != 0 ||
1769: (r = sshpkt_put_u32(ssh, num_prompts)) != 0)
1770: goto out;
1.23 markus 1771:
1.73 markus 1772: debug2("input_userauth_info_req: num_prompts %d", num_prompts);
1.23 markus 1773: for (i = 0; i < num_prompts; i++) {
1.278 markus 1774: if ((r = sshpkt_get_cstring(ssh, &prompt, NULL)) != 0 ||
1775: (r = sshpkt_get_u8(ssh, &echo)) != 0)
1776: goto out;
1.77 markus 1777: response = read_passphrase(prompt, echo ? RP_ECHO : 0);
1.278 markus 1778: if ((r = sshpkt_put_cstring(ssh, response)) != 0)
1779: goto out;
1780: freezero(response, strlen(response));
1.197 djm 1781: free(prompt);
1.278 markus 1782: response = prompt = NULL;
1.23 markus 1783: }
1.278 markus 1784: /* done with parsing incoming message. */
1785: if ((r = sshpkt_get_end(ssh)) != 0 ||
1786: (r = sshpkt_add_padding(ssh, 64)) != 0)
1787: goto out;
1788: r = sshpkt_send(ssh);
1789: out:
1790: if (response)
1791: freezero(response, strlen(response));
1792: free(prompt);
1793: free(name);
1794: free(inst);
1795: free(lang);
1796: return r;
1.68 markus 1797: }
1798:
1.100 markus 1799: static int
1.294 djm 1800: ssh_keysign(struct ssh *ssh, struct sshkey *key, u_char **sigp, size_t *lenp,
1.223 djm 1801: const u_char *data, size_t datalen)
1.100 markus 1802: {
1.223 djm 1803: struct sshbuf *b;
1.101 markus 1804: struct stat st;
1.100 markus 1805: pid_t pid;
1.295 djm 1806: int i, r, to[2], from[2], status;
1807: int sock = ssh_packet_get_connection_in(ssh);
1.223 djm 1808: u_char rversion = 0, version = 2;
1809: void (*osigchld)(int);
1.100 markus 1810:
1.223 djm 1811: *sigp = NULL;
1812: *lenp = 0;
1.100 markus 1813:
1.101 markus 1814: if (stat(_PATH_SSH_KEY_SIGN, &st) < 0) {
1.223 djm 1815: error("%s: not installed: %s", __func__, strerror(errno));
1816: return -1;
1817: }
1818: if (fflush(stdout) != 0) {
1819: error("%s: fflush: %s", __func__, strerror(errno));
1.101 markus 1820: return -1;
1821: }
1.100 markus 1822: if (pipe(to) < 0) {
1.223 djm 1823: error("%s: pipe: %s", __func__, strerror(errno));
1.100 markus 1824: return -1;
1825: }
1826: if (pipe(from) < 0) {
1.223 djm 1827: error("%s: pipe: %s", __func__, strerror(errno));
1.100 markus 1828: return -1;
1829: }
1830: if ((pid = fork()) < 0) {
1.223 djm 1831: error("%s: fork: %s", __func__, strerror(errno));
1.100 markus 1832: return -1;
1833: }
1.223 djm 1834: osigchld = signal(SIGCHLD, SIG_DFL);
1.100 markus 1835: if (pid == 0) {
1.174 dtucker 1836: /* keep the socket on exec */
1.223 djm 1837: fcntl(sock, F_SETFD, 0);
1.100 markus 1838: close(from[0]);
1839: if (dup2(from[1], STDOUT_FILENO) < 0)
1.223 djm 1840: fatal("%s: dup2: %s", __func__, strerror(errno));
1.100 markus 1841: close(to[1]);
1842: if (dup2(to[0], STDIN_FILENO) < 0)
1.223 djm 1843: fatal("%s: dup2: %s", __func__, strerror(errno));
1.103 markus 1844: close(from[1]);
1845: close(to[0]);
1.223 djm 1846: /* Close everything but stdio and the socket */
1847: for (i = STDERR_FILENO + 1; i < sock; i++)
1848: close(i);
1849: closefrom(sock + 1);
1850: debug3("%s: [child] pid=%ld, exec %s",
1851: __func__, (long)getpid(), _PATH_SSH_KEY_SIGN);
1.233 mmcc 1852: execl(_PATH_SSH_KEY_SIGN, _PATH_SSH_KEY_SIGN, (char *)NULL);
1.223 djm 1853: fatal("%s: exec(%s): %s", __func__, _PATH_SSH_KEY_SIGN,
1.100 markus 1854: strerror(errno));
1855: }
1856: close(from[1]);
1857: close(to[0]);
1858:
1.223 djm 1859: if ((b = sshbuf_new()) == NULL)
1860: fatal("%s: sshbuf_new failed", __func__);
1861: /* send # of sock, data to be signed */
1.253 djm 1862: if ((r = sshbuf_put_u32(b, sock)) != 0 ||
1.223 djm 1863: (r = sshbuf_put_string(b, data, datalen)) != 0)
1864: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1865: if (ssh_msg_send(to[1], version, b) == -1)
1866: fatal("%s: couldn't send request", __func__);
1867: sshbuf_reset(b);
1868: r = ssh_msg_recv(from[0], b);
1.101 markus 1869: close(from[0]);
1870: close(to[1]);
1.223 djm 1871: if (r < 0) {
1872: error("%s: no reply", __func__);
1873: goto fail;
1874: }
1.101 markus 1875:
1.223 djm 1876: errno = 0;
1877: while (waitpid(pid, &status, 0) < 0) {
1878: if (errno != EINTR) {
1879: error("%s: waitpid %ld: %s",
1880: __func__, (long)pid, strerror(errno));
1881: goto fail;
1882: }
1883: }
1884: if (!WIFEXITED(status)) {
1885: error("%s: exited abnormally", __func__);
1886: goto fail;
1887: }
1888: if (WEXITSTATUS(status) != 0) {
1889: error("%s: exited with status %d",
1890: __func__, WEXITSTATUS(status));
1891: goto fail;
1892: }
1893: if ((r = sshbuf_get_u8(b, &rversion)) != 0) {
1894: error("%s: buffer error: %s", __func__, ssh_err(r));
1895: goto fail;
1896: }
1897: if (rversion != version) {
1898: error("%s: bad version", __func__);
1899: goto fail;
1900: }
1901: if ((r = sshbuf_get_string(b, sigp, lenp)) != 0) {
1902: error("%s: buffer error: %s", __func__, ssh_err(r));
1903: fail:
1904: signal(SIGCHLD, osigchld);
1905: sshbuf_free(b);
1.100 markus 1906: return -1;
1907: }
1.223 djm 1908: signal(SIGCHLD, osigchld);
1909: sshbuf_free(b);
1.100 markus 1910:
1911: return 0;
1912: }
1913:
1.68 markus 1914: int
1.295 djm 1915: userauth_hostbased(struct ssh *ssh)
1.68 markus 1916: {
1.295 djm 1917: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.223 djm 1918: struct sshkey *private = NULL;
1919: struct sshbuf *b = NULL;
1920: u_char *sig = NULL, *keyblob = NULL;
1921: char *fp = NULL, *chost = NULL, *lname = NULL;
1922: size_t siglen = 0, keylen = 0;
1923: int i, r, success = 0;
1924:
1925: if (authctxt->ktypes == NULL) {
1926: authctxt->oktypes = xstrdup(options.hostbased_key_types);
1927: authctxt->ktypes = authctxt->oktypes;
1928: }
1.213 djm 1929:
1.223 djm 1930: /*
1931: * Work through each listed type pattern in HostbasedKeyTypes,
1932: * trying each hostkey that matches the type in turn.
1933: */
1934: for (;;) {
1935: if (authctxt->active_ktype == NULL)
1936: authctxt->active_ktype = strsep(&authctxt->ktypes, ",");
1937: if (authctxt->active_ktype == NULL ||
1938: *authctxt->active_ktype == '\0')
1939: break;
1940: debug3("%s: trying key type %s", __func__,
1941: authctxt->active_ktype);
1.68 markus 1942:
1.223 djm 1943: /* check for a useful key */
1944: private = NULL;
1945: for (i = 0; i < authctxt->sensitive->nkeys; i++) {
1946: if (authctxt->sensitive->keys[i] == NULL ||
1947: authctxt->sensitive->keys[i]->type == KEY_UNSPEC)
1948: continue;
1949: if (match_pattern_list(
1950: sshkey_ssh_name(authctxt->sensitive->keys[i]),
1.224 djm 1951: authctxt->active_ktype, 0) != 1)
1.223 djm 1952: continue;
1.68 markus 1953: /* we take and free the key */
1.223 djm 1954: private = authctxt->sensitive->keys[i];
1955: authctxt->sensitive->keys[i] = NULL;
1.68 markus 1956: break;
1957: }
1.223 djm 1958: /* Found one */
1959: if (private != NULL)
1960: break;
1961: /* No more keys of this type; advance */
1962: authctxt->active_ktype = NULL;
1.68 markus 1963: }
1.223 djm 1964: if (private == NULL) {
1965: free(authctxt->oktypes);
1966: authctxt->oktypes = authctxt->ktypes = NULL;
1967: authctxt->active_ktype = NULL;
1.109 markus 1968: debug("No more client hostkeys for hostbased authentication.");
1.223 djm 1969: goto out;
1.68 markus 1970: }
1.211 djm 1971:
1.223 djm 1972: if ((fp = sshkey_fingerprint(private, options.fingerprint_hash,
1973: SSH_FP_DEFAULT)) == NULL) {
1974: error("%s: sshkey_fingerprint failed", __func__);
1975: goto out;
1.68 markus 1976: }
1.223 djm 1977: debug("%s: trying hostkey %s %s",
1978: __func__, sshkey_ssh_name(private), fp);
1.211 djm 1979:
1.84 markus 1980: /* figure out a name for the client host */
1.295 djm 1981: lname = get_local_name(ssh_packet_get_connection_in(ssh));
1982: if (lname == NULL) {
1.223 djm 1983: error("%s: cannot get local ipaddr/name", __func__);
1984: goto out;
1.84 markus 1985: }
1.223 djm 1986:
1987: /* XXX sshbuf_put_stringf? */
1988: xasprintf(&chost, "%s.", lname);
1989: debug2("%s: chost %s", __func__, chost);
1.84 markus 1990:
1.68 markus 1991: /* construct data */
1.223 djm 1992: if ((b = sshbuf_new()) == NULL) {
1993: error("%s: sshbuf_new failed", __func__);
1994: goto out;
1995: }
1996: if ((r = sshkey_to_blob(private, &keyblob, &keylen)) != 0) {
1997: error("%s: sshkey_to_blob: %s", __func__, ssh_err(r));
1998: goto out;
1999: }
2000: if ((r = sshbuf_put_string(b, session_id2, session_id2_len)) != 0 ||
2001: (r = sshbuf_put_u8(b, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
2002: (r = sshbuf_put_cstring(b, authctxt->server_user)) != 0 ||
1.267 djm 2003: (r = sshbuf_put_cstring(b, authctxt->service)) != 0 ||
1.223 djm 2004: (r = sshbuf_put_cstring(b, authctxt->method->name)) != 0 ||
1.279 markus 2005: (r = sshbuf_put_cstring(b, sshkey_ssh_name(private))) != 0 ||
1.223 djm 2006: (r = sshbuf_put_string(b, keyblob, keylen)) != 0 ||
2007: (r = sshbuf_put_cstring(b, chost)) != 0 ||
2008: (r = sshbuf_put_cstring(b, authctxt->local_user)) != 0) {
2009: error("%s: buffer error: %s", __func__, ssh_err(r));
2010: goto out;
2011: }
2012:
1.68 markus 2013: #ifdef DEBUG_PK
1.223 djm 2014: sshbuf_dump(b, stderr);
1.68 markus 2015: #endif
1.294 djm 2016: if ((r = ssh_keysign(ssh, private, &sig, &siglen,
2017: sshbuf_ptr(b), sshbuf_len(b))) != 0) {
1.223 djm 2018: error("sign using hostkey %s %s failed",
2019: sshkey_ssh_name(private), fp);
2020: goto out;
2021: }
2022: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
2023: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
2024: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
2025: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1.279 markus 2026: (r = sshpkt_put_cstring(ssh, sshkey_ssh_name(private))) != 0 ||
1.223 djm 2027: (r = sshpkt_put_string(ssh, keyblob, keylen)) != 0 ||
2028: (r = sshpkt_put_cstring(ssh, chost)) != 0 ||
2029: (r = sshpkt_put_cstring(ssh, authctxt->local_user)) != 0 ||
2030: (r = sshpkt_put_string(ssh, sig, siglen)) != 0 ||
2031: (r = sshpkt_send(ssh)) != 0) {
2032: error("%s: packet error: %s", __func__, ssh_err(r));
2033: goto out;
2034: }
2035: success = 1;
2036:
2037: out:
1.278 markus 2038: if (sig != NULL)
2039: freezero(sig, siglen);
1.223 djm 2040: free(keyblob);
2041: free(lname);
2042: free(fp);
1.197 djm 2043: free(chost);
1.223 djm 2044: sshkey_free(private);
2045: sshbuf_free(b);
1.68 markus 2046:
1.223 djm 2047: return success;
1.23 markus 2048: }
1.170 djm 2049:
1.20 markus 2050: /* find auth method */
2051:
2052: /*
2053: * given auth method name, if configurable options permit this method fill
2054: * in auth_ident field and return true, otherwise return false.
2055: */
1.76 itojun 2056: static int
1.20 markus 2057: authmethod_is_enabled(Authmethod *method)
2058: {
2059: if (method == NULL)
2060: return 0;
2061: /* return false if options indicate this method is disabled */
2062: if (method->enabled == NULL || *method->enabled == 0)
2063: return 0;
2064: /* return false if batch mode is enabled but method needs interactive mode */
2065: if (method->batch_flag != NULL && *method->batch_flag != 0)
2066: return 0;
2067: return 1;
2068: }
2069:
1.76 itojun 2070: static Authmethod *
1.20 markus 2071: authmethod_lookup(const char *name)
1.1 markus 2072: {
1.20 markus 2073: Authmethod *method = NULL;
2074: if (name != NULL)
2075: for (method = authmethods; method->name != NULL; method++)
2076: if (strcmp(name, method->name) == 0)
2077: return method;
2078: debug2("Unrecognized authentication method name: %s", name ? name : "NULL");
2079: return NULL;
2080: }
1.1 markus 2081:
1.53 markus 2082: /* XXX internal state */
2083: static Authmethod *current = NULL;
2084: static char *supported = NULL;
2085: static char *preferred = NULL;
1.105 deraadt 2086:
1.20 markus 2087: /*
2088: * Given the authentication method list sent by the server, return the
2089: * next method we should try. If the server initially sends a nil list,
1.67 markus 2090: * use a built-in default list.
1.41 stevesk 2091: */
1.76 itojun 2092: static Authmethod *
1.20 markus 2093: authmethod_get(char *authlist)
2094: {
1.53 markus 2095: char *name = NULL;
1.97 markus 2096: u_int next;
1.41 stevesk 2097:
1.20 markus 2098: /* Use a suitable default if we're passed a nil list. */
2099: if (authlist == NULL || strlen(authlist) == 0)
1.53 markus 2100: authlist = options.preferred_authentications;
1.20 markus 2101:
1.53 markus 2102: if (supported == NULL || strcmp(authlist, supported) != 0) {
2103: debug3("start over, passed a different list %s", authlist);
1.197 djm 2104: free(supported);
1.53 markus 2105: supported = xstrdup(authlist);
2106: preferred = options.preferred_authentications;
2107: debug3("preferred %s", preferred);
2108: current = NULL;
2109: } else if (current != NULL && authmethod_is_enabled(current))
2110: return current;
1.20 markus 2111:
1.53 markus 2112: for (;;) {
2113: if ((name = match_list(preferred, supported, &next)) == NULL) {
1.109 markus 2114: debug("No more authentication methods to try.");
1.53 markus 2115: current = NULL;
2116: return NULL;
2117: }
2118: preferred += next;
1.23 markus 2119: debug3("authmethod_lookup %s", name);
1.53 markus 2120: debug3("remaining preferred: %s", preferred);
2121: if ((current = authmethod_lookup(name)) != NULL &&
2122: authmethod_is_enabled(current)) {
1.23 markus 2123: debug3("authmethod_is_enabled %s", name);
1.109 markus 2124: debug("Next authentication method: %s", name);
1.197 djm 2125: free(name);
1.53 markus 2126: return current;
1.23 markus 2127: }
1.198 dtucker 2128: free(name);
1.1 markus 2129: }
1.53 markus 2130: }
1.1 markus 2131:
1.79 stevesk 2132: static char *
1.53 markus 2133: authmethods_get(void)
2134: {
2135: Authmethod *method = NULL;
1.278 markus 2136: struct sshbuf *b;
1.93 markus 2137: char *list;
1.278 markus 2138: int r;
1.27 provos 2139:
1.278 markus 2140: if ((b = sshbuf_new()) == NULL)
2141: fatal("%s: sshbuf_new failed", __func__);
1.53 markus 2142: for (method = authmethods; method->name != NULL; method++) {
2143: if (authmethod_is_enabled(method)) {
1.278 markus 2144: if ((r = sshbuf_putf(b, "%s%s",
2145: sshbuf_len(b) ? "," : "", method->name)) != 0)
2146: fatal("%s: buffer error: %s",
2147: __func__, ssh_err(r));
1.53 markus 2148: }
2149: }
1.278 markus 2150: if ((list = sshbuf_dup_string(b)) == NULL)
1.242 djm 2151: fatal("%s: sshbuf_dup_string failed", __func__);
1.278 markus 2152: sshbuf_free(b);
1.93 markus 2153: return list;
1.1 markus 2154: }