Annotation of src/usr.bin/ssh/sshconnect2.c, Revision 1.223
1.223 ! djm 1: /* $OpenBSD: sshconnect2.c,v 1.222 2015/01/28 22:36:00 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"
1.1 markus 46: #include "buffer.h"
47: #include "packet.h"
48: #include "compat.h"
1.37 markus 49: #include "cipher.h"
1.160 deraadt 50: #include "key.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"
1.22 provos 68:
1.121 markus 69: #ifdef GSSAPI
70: #include "ssh-gss.h"
71: #endif
72:
1.1 markus 73: /* import */
74: extern char *client_version_string;
75: extern char *server_version_string;
76: extern Options options;
77:
78: /*
79: * SSH2 key exchange
80: */
81:
1.32 markus 82: u_char *session_id2 = NULL;
1.120 markus 83: u_int session_id2_len = 0;
1.1 markus 84:
1.61 markus 85: char *xxx_host;
86: struct sockaddr *xxx_hostaddr;
87:
1.76 itojun 88: static int
1.219 markus 89: verify_host_key_callback(Key *hostkey, struct ssh *ssh)
1.61 markus 90: {
1.75 markus 91: if (verify_host_key(xxx_host, xxx_hostaddr, hostkey) == -1)
1.83 markus 92: fatal("Host key verification failed.");
1.61 markus 93: return 0;
94: }
95:
1.186 djm 96: static char *
97: order_hostkeyalgs(char *host, struct sockaddr *hostaddr, u_short port)
98: {
99: char *oavail, *avail, *first, *last, *alg, *hostname, *ret;
100: size_t maxlen;
101: struct hostkeys *hostkeys;
102: int ktype;
1.188 djm 103: u_int i;
1.186 djm 104:
105: /* Find all hostkeys for this hostname */
106: get_hostfile_hostname_ipaddr(host, hostaddr, port, &hostname, NULL);
107: hostkeys = init_hostkeys();
1.188 djm 108: for (i = 0; i < options.num_user_hostfiles; i++)
109: load_hostkeys(hostkeys, hostname, options.user_hostfiles[i]);
110: for (i = 0; i < options.num_system_hostfiles; i++)
111: load_hostkeys(hostkeys, hostname, options.system_hostfiles[i]);
1.186 djm 112:
113: oavail = avail = xstrdup(KEX_DEFAULT_PK_ALG);
114: maxlen = strlen(avail) + 1;
115: first = xmalloc(maxlen);
116: last = xmalloc(maxlen);
117: *first = *last = '\0';
118:
119: #define ALG_APPEND(to, from) \
120: do { \
121: if (*to != '\0') \
122: strlcat(to, ",", maxlen); \
123: strlcat(to, from, maxlen); \
124: } while (0)
125:
126: while ((alg = strsep(&avail, ",")) && *alg != '\0') {
1.214 djm 127: if ((ktype = sshkey_type_from_name(alg)) == KEY_UNSPEC)
1.186 djm 128: fatal("%s: unknown alg %s", __func__, alg);
129: if (lookup_key_in_hostkeys_by_type(hostkeys,
1.214 djm 130: sshkey_type_plain(ktype), NULL))
1.186 djm 131: ALG_APPEND(first, alg);
132: else
133: ALG_APPEND(last, alg);
134: }
135: #undef ALG_APPEND
1.216 djm 136: xasprintf(&ret, "%s%s%s", first,
137: (*first == '\0' || *last == '\0') ? "" : ",", last);
1.186 djm 138: if (*first != '\0')
139: debug3("%s: prefer hostkeyalgs: %s", __func__, first);
140:
1.197 djm 141: free(first);
142: free(last);
143: free(hostname);
144: free(oavail);
1.186 djm 145: free_hostkeys(hostkeys);
146:
147: return ret;
148: }
149:
1.1 markus 150: void
1.186 djm 151: ssh_kex2(char *host, struct sockaddr *hostaddr, u_short port)
1.22 provos 152: {
1.205 markus 153: char *myproposal[PROPOSAL_MAX] = { KEX_CLIENT };
1.219 markus 154: struct kex *kex;
1.221 markus 155: int r;
1.61 markus 156:
157: xxx_host = host;
158: xxx_hostaddr = hostaddr;
1.22 provos 159:
1.29 markus 160: if (options.ciphers == (char *)-1) {
1.116 itojun 161: logit("No valid ciphers for protocol version 2 given, using defaults.");
1.29 markus 162: options.ciphers = NULL;
1.24 markus 163: }
1.22 provos 164: if (options.ciphers != NULL) {
165: myproposal[PROPOSAL_ENC_ALGS_CTOS] =
166: myproposal[PROPOSAL_ENC_ALGS_STOC] = options.ciphers;
167: }
1.60 stevesk 168: myproposal[PROPOSAL_ENC_ALGS_CTOS] =
169: compat_cipher_proposal(myproposal[PROPOSAL_ENC_ALGS_CTOS]);
170: myproposal[PROPOSAL_ENC_ALGS_STOC] =
171: compat_cipher_proposal(myproposal[PROPOSAL_ENC_ALGS_STOC]);
1.22 provos 172: if (options.compression) {
1.47 markus 173: myproposal[PROPOSAL_COMP_ALGS_CTOS] =
1.141 markus 174: myproposal[PROPOSAL_COMP_ALGS_STOC] = "zlib@openssh.com,zlib,none";
1.22 provos 175: } else {
1.47 markus 176: myproposal[PROPOSAL_COMP_ALGS_CTOS] =
1.141 markus 177: myproposal[PROPOSAL_COMP_ALGS_STOC] = "none,zlib@openssh.com,zlib";
1.47 markus 178: }
179: if (options.macs != NULL) {
180: myproposal[PROPOSAL_MAC_ALGS_CTOS] =
181: myproposal[PROPOSAL_MAC_ALGS_STOC] = options.macs;
1.22 provos 182: }
1.70 markus 183: if (options.hostkeyalgorithms != NULL)
1.88 deraadt 184: myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] =
1.200 djm 185: compat_pkalg_proposal(options.hostkeyalgorithms);
1.186 djm 186: else {
187: /* Prefer algorithms that we already have keys for */
188: myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] =
1.200 djm 189: compat_pkalg_proposal(
190: order_hostkeyalgs(host, hostaddr, port));
1.186 djm 191: }
1.185 djm 192: if (options.kex_algorithms != NULL)
193: myproposal[PROPOSAL_KEX_ALGS] = options.kex_algorithms;
1.206 djm 194: myproposal[PROPOSAL_KEX_ALGS] = compat_kex_proposal(
195: myproposal[PROPOSAL_KEX_ALGS]);
1.115 markus 196:
1.196 dtucker 197: if (options.rekey_limit || options.rekey_interval)
198: packet_set_rekey_limits((u_int32_t)options.rekey_limit,
199: (time_t)options.rekey_interval);
1.22 provos 200:
1.65 markus 201: /* start key exchange */
1.221 markus 202: if ((r = kex_setup(active_state, myproposal)) != 0)
203: fatal("kex_setup: %s", ssh_err(r));
1.219 markus 204: kex = active_state->kex;
1.207 markus 205: #ifdef WITH_OPENSSL
1.111 markus 206: kex->kex[KEX_DH_GRP1_SHA1] = kexdh_client;
1.138 djm 207: kex->kex[KEX_DH_GRP14_SHA1] = kexdh_client;
1.111 markus 208: kex->kex[KEX_DH_GEX_SHA1] = kexgex_client;
1.147 djm 209: kex->kex[KEX_DH_GEX_SHA256] = kexgex_client;
1.184 djm 210: kex->kex[KEX_ECDH_SHA2] = kexecdh_client;
1.207 markus 211: #endif
1.199 markus 212: kex->kex[KEX_C25519_SHA256] = kexc25519_client;
1.61 markus 213: kex->client_version_string=client_version_string;
214: kex->server_version_string=server_version_string;
1.75 markus 215: kex->verify_host_key=&verify_host_key_callback;
1.22 provos 216:
1.219 markus 217: dispatch_run(DISPATCH_BLOCK, &kex->done, active_state);
1.173 andreas 218:
219: if (options.use_roaming && !kex->roaming) {
220: debug("Roaming not allowed by server");
221: options.use_roaming = 0;
222: }
1.62 markus 223:
224: session_id2 = kex->session_id;
225: session_id2_len = kex->session_id_len;
1.22 provos 226:
227: #ifdef DEBUG_KEXDH
228: /* send 1st encrypted/maced/compressed message */
229: packet_start(SSH2_MSG_IGNORE);
230: packet_put_cstring("markus");
231: packet_send();
232: packet_write_wait();
233: #endif
1.1 markus 234: }
1.11 markus 235:
1.1 markus 236: /*
237: * Authenticate user
238: */
1.20 markus 239:
1.214 djm 240: typedef struct cauthctxt Authctxt;
241: typedef struct cauthmethod Authmethod;
1.117 markus 242: typedef struct identity Identity;
243: typedef struct idlist Idlist;
1.20 markus 244:
1.117 markus 245: struct identity {
246: TAILQ_ENTRY(identity) next;
1.214 djm 247: int agent_fd; /* >=0 if agent supports key */
248: struct sshkey *key; /* public/private key */
1.117 markus 249: char *filename; /* comment for agent-only keys */
250: int tried;
251: int isprivate; /* key points to the private key */
1.191 dtucker 252: int userprovided;
1.117 markus 253: };
254: TAILQ_HEAD(idlist, identity);
1.20 markus 255:
1.214 djm 256: struct cauthctxt {
1.20 markus 257: const char *server_user;
1.68 markus 258: const char *local_user;
1.20 markus 259: const char *host;
260: const char *service;
1.214 djm 261: struct cauthmethod *method;
1.183 djm 262: sig_atomic_t success;
1.51 markus 263: char *authlist;
1.214 djm 264: int attempt;
1.68 markus 265: /* pubkey */
1.214 djm 266: struct idlist keys;
267: int agent_fd;
1.68 markus 268: /* hostbased */
1.100 markus 269: Sensitive *sensitive;
1.223 ! djm 270: char *oktypes, *ktypes;
! 271: const char *active_ktype;
1.82 markus 272: /* kbd-interactive */
273: int info_req_seen;
1.121 markus 274: /* generic */
275: void *methoddata;
1.20 markus 276: };
1.214 djm 277:
278: struct cauthmethod {
1.20 markus 279: char *name; /* string to compare against server's list */
280: int (*userauth)(Authctxt *authctxt);
1.170 djm 281: void (*cleanup)(Authctxt *authctxt);
1.20 markus 282: int *enabled; /* flag in option struct that enables method */
283: int *batch_flag; /* flag in option struct that disables method */
284: };
285:
1.218 markus 286: int input_userauth_success(int, u_int32_t, void *);
287: int input_userauth_success_unexpected(int, u_int32_t, void *);
288: int input_userauth_failure(int, u_int32_t, void *);
289: int input_userauth_banner(int, u_int32_t, void *);
290: int input_userauth_error(int, u_int32_t, void *);
291: int input_userauth_info_req(int, u_int32_t, void *);
292: int input_userauth_pk_ok(int, u_int32_t, void *);
293: int input_userauth_passwd_changereq(int, u_int32_t, void *);
1.86 itojun 294:
295: int userauth_none(Authctxt *);
296: int userauth_pubkey(Authctxt *);
297: int userauth_passwd(Authctxt *);
298: int userauth_kbdint(Authctxt *);
299: int userauth_hostbased(Authctxt *);
1.20 markus 300:
1.121 markus 301: #ifdef GSSAPI
302: int userauth_gssapi(Authctxt *authctxt);
1.218 markus 303: int input_gssapi_response(int type, u_int32_t, void *);
304: int input_gssapi_token(int type, u_int32_t, void *);
305: int input_gssapi_hash(int type, u_int32_t, void *);
306: int input_gssapi_error(int, u_int32_t, void *);
307: int input_gssapi_errtok(int, u_int32_t, void *);
1.121 markus 308: #endif
309:
1.86 itojun 310: void userauth(Authctxt *, char *);
1.51 markus 311:
1.117 markus 312: static int sign_and_send_pubkey(Authctxt *, Identity *);
313: static void pubkey_prepare(Authctxt *);
314: static void pubkey_cleanup(Authctxt *);
1.191 dtucker 315: static Key *load_identity_file(char *, int);
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
1.68 markus 358: ssh_userauth2(const char *local_user, const char *server_user, char *host,
1.100 markus 359: Sensitive *sensitive)
1.20 markus 360: {
361: Authctxt authctxt;
362: int type;
1.39 markus 363:
1.73 markus 364: if (options.challenge_response_authentication)
1.39 markus 365: options.kbd_interactive_authentication = 1;
1.20 markus 366:
367: packet_start(SSH2_MSG_SERVICE_REQUEST);
368: packet_put_cstring("ssh-userauth");
369: packet_send();
1.108 markus 370: debug("SSH2_MSG_SERVICE_REQUEST sent");
1.20 markus 371: packet_write_wait();
1.91 markus 372: type = packet_read();
1.108 markus 373: if (type != SSH2_MSG_SERVICE_ACCEPT)
374: fatal("Server denied authentication request: %d", type);
1.20 markus 375: if (packet_remaining() > 0) {
1.91 markus 376: char *reply = packet_get_string(NULL);
1.108 markus 377: debug2("service_accept: %s", reply);
1.197 djm 378: free(reply);
1.20 markus 379: } else {
1.109 markus 380: debug2("buggy server: service_accept w/o service");
1.20 markus 381: }
1.90 markus 382: packet_check_eom();
1.108 markus 383: debug("SSH2_MSG_SERVICE_ACCEPT received");
1.20 markus 384:
1.53 markus 385: if (options.preferred_authentications == NULL)
386: options.preferred_authentications = authmethods_get();
387:
1.20 markus 388: /* setup authentication context */
1.82 markus 389: memset(&authctxt, 0, sizeof(authctxt));
1.117 markus 390: pubkey_prepare(&authctxt);
1.20 markus 391: authctxt.server_user = server_user;
1.68 markus 392: authctxt.local_user = local_user;
1.20 markus 393: authctxt.host = host;
394: authctxt.service = "ssh-connection"; /* service name */
395: authctxt.success = 0;
1.23 markus 396: authctxt.method = authmethod_lookup("none");
1.51 markus 397: authctxt.authlist = NULL;
1.121 markus 398: authctxt.methoddata = NULL;
1.100 markus 399: authctxt.sensitive = sensitive;
1.223 ! djm 400: authctxt.active_ktype = authctxt.oktypes = authctxt.ktypes = NULL;
1.82 markus 401: authctxt.info_req_seen = 0;
1.215 djm 402: authctxt.agent_fd = -1;
1.23 markus 403: if (authctxt.method == NULL)
404: fatal("ssh_userauth2: internal error: cannot send userauth none request");
1.20 markus 405:
406: /* initial userauth request */
1.23 markus 407: userauth_none(&authctxt);
1.20 markus 408:
1.65 markus 409: dispatch_init(&input_userauth_error);
1.20 markus 410: dispatch_set(SSH2_MSG_USERAUTH_SUCCESS, &input_userauth_success);
411: dispatch_set(SSH2_MSG_USERAUTH_FAILURE, &input_userauth_failure);
1.35 markus 412: dispatch_set(SSH2_MSG_USERAUTH_BANNER, &input_userauth_banner);
1.20 markus 413: dispatch_run(DISPATCH_BLOCK, &authctxt.success, &authctxt); /* loop until success */
414:
1.117 markus 415: pubkey_cleanup(&authctxt);
1.119 markus 416: dispatch_range(SSH2_MSG_USERAUTH_MIN, SSH2_MSG_USERAUTH_MAX, NULL);
417:
1.109 markus 418: debug("Authentication succeeded (%s).", authctxt.method->name);
1.20 markus 419: }
1.119 markus 420:
1.20 markus 421: void
1.51 markus 422: userauth(Authctxt *authctxt, char *authlist)
423: {
1.170 djm 424: if (authctxt->method != NULL && authctxt->method->cleanup != NULL)
425: authctxt->method->cleanup(authctxt);
426:
1.197 djm 427: free(authctxt->methoddata);
428: authctxt->methoddata = NULL;
1.51 markus 429: if (authlist == NULL) {
430: authlist = authctxt->authlist;
431: } else {
1.197 djm 432: free(authctxt->authlist);
1.51 markus 433: authctxt->authlist = authlist;
434: }
435: for (;;) {
436: Authmethod *method = authmethod_get(authlist);
437: if (method == NULL)
438: fatal("Permission denied (%s).", authlist);
439: authctxt->method = method;
1.119 markus 440:
441: /* reset the per method handler */
442: dispatch_range(SSH2_MSG_USERAUTH_PER_METHOD_MIN,
443: SSH2_MSG_USERAUTH_PER_METHOD_MAX, NULL);
444:
445: /* and try new method */
1.51 markus 446: if (method->userauth(authctxt) != 0) {
447: debug2("we sent a %s packet, wait for reply", method->name);
448: break;
449: } else {
450: debug2("we did not send a packet, disable method");
451: method->enabled = NULL;
452: }
453: }
454: }
1.105 deraadt 455:
1.169 djm 456: /* ARGSUSED */
1.218 markus 457: int
1.92 markus 458: input_userauth_error(int type, u_int32_t seq, void *ctxt)
1.20 markus 459: {
1.35 markus 460: fatal("input_userauth_error: bad message during authentication: "
1.140 djm 461: "type %d", type);
1.218 markus 462: return 0;
1.35 markus 463: }
1.105 deraadt 464:
1.169 djm 465: /* ARGSUSED */
1.218 markus 466: int
1.92 markus 467: input_userauth_banner(int type, u_int32_t seq, void *ctxt)
1.35 markus 468: {
1.166 djm 469: char *msg, *raw, *lang;
470: u_int len;
1.126 deraadt 471:
1.35 markus 472: debug3("input_userauth_banner");
1.166 djm 473: raw = packet_get_string(&len);
1.35 markus 474: lang = packet_get_string(NULL);
1.167 markus 475: if (len > 0 && options.log_level >= SYSLOG_LEVEL_INFO) {
1.166 djm 476: if (len > 65536)
477: len = 65536;
1.168 deraadt 478: msg = xmalloc(len * 4 + 1); /* max expansion from strnvis() */
1.177 dtucker 479: strnvis(msg, raw, len * 4 + 1, VIS_SAFE|VIS_OCTAL|VIS_NOSLASH);
1.125 dtucker 480: fprintf(stderr, "%s", msg);
1.197 djm 481: free(msg);
1.166 djm 482: }
1.197 djm 483: free(raw);
484: free(lang);
1.218 markus 485: return 0;
1.20 markus 486: }
1.105 deraadt 487:
1.169 djm 488: /* ARGSUSED */
1.218 markus 489: int
1.92 markus 490: input_userauth_success(int type, u_int32_t seq, void *ctxt)
1.20 markus 491: {
492: Authctxt *authctxt = ctxt;
1.172 djm 493:
1.20 markus 494: if (authctxt == NULL)
495: fatal("input_userauth_success: no authentication context");
1.197 djm 496: free(authctxt->authlist);
497: authctxt->authlist = NULL;
1.172 djm 498: if (authctxt->method != NULL && authctxt->method->cleanup != NULL)
499: authctxt->method->cleanup(authctxt);
1.197 djm 500: free(authctxt->methoddata);
501: authctxt->methoddata = NULL;
1.20 markus 502: authctxt->success = 1; /* break out */
1.218 markus 503: return 0;
1.20 markus 504: }
1.105 deraadt 505:
1.218 markus 506: int
1.172 djm 507: input_userauth_success_unexpected(int type, u_int32_t seq, void *ctxt)
508: {
509: Authctxt *authctxt = ctxt;
510:
511: if (authctxt == NULL)
512: fatal("%s: no authentication context", __func__);
513:
514: fatal("Unexpected authentication success during %s.",
515: authctxt->method->name);
1.218 markus 516: return 0;
1.172 djm 517: }
518:
1.169 djm 519: /* ARGSUSED */
1.218 markus 520: int
1.92 markus 521: input_userauth_failure(int type, u_int32_t seq, void *ctxt)
1.20 markus 522: {
523: Authctxt *authctxt = ctxt;
524: char *authlist = NULL;
525: int partial;
526:
527: if (authctxt == NULL)
528: fatal("input_userauth_failure: no authentication context");
529:
1.23 markus 530: authlist = packet_get_string(NULL);
1.20 markus 531: partial = packet_get_char();
1.90 markus 532: packet_check_eom();
1.20 markus 533:
1.193 markus 534: if (partial != 0) {
1.116 itojun 535: logit("Authenticated with partial success.");
1.193 markus 536: /* reset state */
537: pubkey_cleanup(authctxt);
538: pubkey_prepare(authctxt);
539: }
1.109 markus 540: debug("Authentications that can continue: %s", authlist);
1.20 markus 541:
1.51 markus 542: userauth(authctxt, authlist);
1.218 markus 543: return 0;
1.51 markus 544: }
1.169 djm 545:
546: /* ARGSUSED */
1.218 markus 547: int
1.92 markus 548: input_userauth_pk_ok(int type, u_int32_t seq, void *ctxt)
1.51 markus 549: {
550: Authctxt *authctxt = ctxt;
551: Key *key = NULL;
1.117 markus 552: Identity *id = NULL;
1.51 markus 553: Buffer b;
1.96 markus 554: int pktype, sent = 0;
555: u_int alen, blen;
556: char *pkalg, *fp;
557: u_char *pkblob;
1.51 markus 558:
559: if (authctxt == NULL)
560: fatal("input_userauth_pk_ok: no authentication context");
561: if (datafellows & SSH_BUG_PKOK) {
562: /* this is similar to SSH_BUG_PKAUTH */
563: debug2("input_userauth_pk_ok: SSH_BUG_PKOK");
564: pkblob = packet_get_string(&blen);
565: buffer_init(&b);
566: buffer_append(&b, pkblob, blen);
567: pkalg = buffer_get_string(&b, &alen);
568: buffer_free(&b);
569: } else {
570: pkalg = packet_get_string(&alen);
571: pkblob = packet_get_string(&blen);
572: }
1.90 markus 573: packet_check_eom();
1.51 markus 574:
1.117 markus 575: debug("Server accepts key: pkalg %s blen %u", pkalg, blen);
1.51 markus 576:
1.117 markus 577: if ((pktype = key_type_from_name(pkalg)) == KEY_UNSPEC) {
578: debug("unknown pkalg %s", pkalg);
579: goto done;
580: }
581: if ((key = key_from_blob(pkblob, blen)) == NULL) {
582: debug("no key from blob. pkalg %s", pkalg);
583: goto done;
584: }
585: if (key->type != pktype) {
586: error("input_userauth_pk_ok: type mismatch "
587: "for decoded key (received %d, expected %d)",
588: key->type, pktype);
589: goto done;
590: }
1.222 djm 591: if ((fp = sshkey_fingerprint(key, options.fingerprint_hash,
592: SSH_FP_DEFAULT)) == NULL)
593: goto done;
1.117 markus 594: debug2("input_userauth_pk_ok: fp %s", fp);
1.197 djm 595: free(fp);
1.117 markus 596:
1.127 markus 597: /*
598: * search keys in the reverse order, because last candidate has been
599: * moved to the end of the queue. this also avoids confusion by
600: * duplicate keys
601: */
1.136 henning 602: TAILQ_FOREACH_REVERSE(id, &authctxt->keys, idlist, next) {
1.117 markus 603: if (key_equal(key, id->key)) {
604: sent = sign_and_send_pubkey(authctxt, id);
1.51 markus 605: break;
606: }
1.117 markus 607: }
608: done:
1.51 markus 609: if (key != NULL)
610: key_free(key);
1.197 djm 611: free(pkalg);
612: free(pkblob);
1.51 markus 613:
1.106 deraadt 614: /* try another method if we did not send a packet */
1.51 markus 615: if (sent == 0)
616: userauth(authctxt, NULL);
1.218 markus 617: return 0;
1.20 markus 618: }
1.121 markus 619:
620: #ifdef GSSAPI
1.133 djm 621: int
1.121 markus 622: userauth_gssapi(Authctxt *authctxt)
623: {
624: Gssctxt *gssctxt = NULL;
1.128 avsm 625: static gss_OID_set gss_supported = NULL;
1.139 djm 626: static u_int mech = 0;
1.121 markus 627: OM_uint32 min;
628: int ok = 0;
629:
630: /* Try one GSSAPI method at a time, rather than sending them all at
631: * once. */
632:
1.128 avsm 633: if (gss_supported == NULL)
634: gss_indicate_mechs(&min, &gss_supported);
1.121 markus 635:
636: /* Check to see if the mechanism is usable before we offer it */
1.128 avsm 637: while (mech < gss_supported->count && !ok) {
1.121 markus 638: /* My DER encoding requires length<128 */
1.128 avsm 639: if (gss_supported->elements[mech].length < 128 &&
1.161 djm 640: ssh_gssapi_check_mechanism(&gssctxt,
641: &gss_supported->elements[mech], authctxt->host)) {
1.121 markus 642: ok = 1; /* Mechanism works */
643: } else {
644: mech++;
645: }
646: }
647:
1.161 djm 648: if (!ok)
1.139 djm 649: return 0;
1.121 markus 650:
651: authctxt->methoddata=(void *)gssctxt;
652:
653: packet_start(SSH2_MSG_USERAUTH_REQUEST);
654: packet_put_cstring(authctxt->server_user);
655: packet_put_cstring(authctxt->service);
656: packet_put_cstring(authctxt->method->name);
657:
658: packet_put_int(1);
659:
1.129 markus 660: packet_put_int((gss_supported->elements[mech].length) + 2);
661: packet_put_char(SSH_GSS_OIDTYPE);
662: packet_put_char(gss_supported->elements[mech].length);
663: packet_put_raw(gss_supported->elements[mech].elements,
664: gss_supported->elements[mech].length);
1.121 markus 665:
666: packet_send();
667:
668: dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_RESPONSE, &input_gssapi_response);
669: dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, &input_gssapi_token);
670: dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERROR, &input_gssapi_error);
671: dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK, &input_gssapi_errtok);
672:
673: mech++; /* Move along to next candidate */
674:
675: return 1;
676: }
677:
1.130 markus 678: static OM_uint32
679: process_gssapi_token(void *ctxt, gss_buffer_t recv_tok)
680: {
681: Authctxt *authctxt = ctxt;
682: Gssctxt *gssctxt = authctxt->methoddata;
683: gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
1.142 djm 684: gss_buffer_desc mic = GSS_C_EMPTY_BUFFER;
685: gss_buffer_desc gssbuf;
1.132 markus 686: OM_uint32 status, ms, flags;
687: Buffer b;
1.133 djm 688:
1.130 markus 689: status = ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
1.132 markus 690: recv_tok, &send_tok, &flags);
1.130 markus 691:
692: if (send_tok.length > 0) {
693: if (GSS_ERROR(status))
694: packet_start(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK);
695: else
696: packet_start(SSH2_MSG_USERAUTH_GSSAPI_TOKEN);
1.133 djm 697:
1.130 markus 698: packet_put_string(send_tok.value, send_tok.length);
699: packet_send();
700: gss_release_buffer(&ms, &send_tok);
701: }
1.133 djm 702:
1.130 markus 703: if (status == GSS_S_COMPLETE) {
1.132 markus 704: /* send either complete or MIC, depending on mechanism */
705: if (!(flags & GSS_C_INTEG_FLAG)) {
706: packet_start(SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE);
707: packet_send();
708: } else {
709: ssh_gssapi_buildmic(&b, authctxt->server_user,
710: authctxt->service, "gssapi-with-mic");
711:
712: gssbuf.value = buffer_ptr(&b);
713: gssbuf.length = buffer_len(&b);
1.133 djm 714:
1.132 markus 715: status = ssh_gssapi_sign(gssctxt, &gssbuf, &mic);
1.133 djm 716:
1.132 markus 717: if (!GSS_ERROR(status)) {
718: packet_start(SSH2_MSG_USERAUTH_GSSAPI_MIC);
719: packet_put_string(mic.value, mic.length);
1.133 djm 720:
1.132 markus 721: packet_send();
722: }
1.133 djm 723:
1.132 markus 724: buffer_free(&b);
725: gss_release_buffer(&ms, &mic);
1.133 djm 726: }
1.130 markus 727: }
1.133 djm 728:
1.130 markus 729: return status;
730: }
731:
1.169 djm 732: /* ARGSUSED */
1.220 djm 733: int
1.121 markus 734: input_gssapi_response(int type, u_int32_t plen, void *ctxt)
735: {
736: Authctxt *authctxt = ctxt;
737: Gssctxt *gssctxt;
738: int oidlen;
739: char *oidv;
740:
741: if (authctxt == NULL)
742: fatal("input_gssapi_response: no authentication context");
743: gssctxt = authctxt->methoddata;
744:
745: /* Setup our OID */
746: oidv = packet_get_string(&oidlen);
747:
1.129 markus 748: if (oidlen <= 2 ||
749: oidv[0] != SSH_GSS_OIDTYPE ||
750: oidv[1] != oidlen - 2) {
1.197 djm 751: free(oidv);
1.129 markus 752: debug("Badly encoded mechanism OID received");
753: userauth(authctxt, NULL);
1.220 djm 754: return 0;
1.121 markus 755: }
1.129 markus 756:
757: if (!ssh_gssapi_check_oid(gssctxt, oidv + 2, oidlen - 2))
758: fatal("Server returned different OID than expected");
1.121 markus 759:
760: packet_check_eom();
761:
1.197 djm 762: free(oidv);
1.121 markus 763:
1.130 markus 764: if (GSS_ERROR(process_gssapi_token(ctxt, GSS_C_NO_BUFFER))) {
1.121 markus 765: /* Start again with next method on list */
766: debug("Trying to start again");
767: userauth(authctxt, NULL);
1.220 djm 768: return 0;
1.121 markus 769: }
1.220 djm 770: return 0;
1.121 markus 771: }
772:
1.169 djm 773: /* ARGSUSED */
1.220 djm 774: int
1.121 markus 775: input_gssapi_token(int type, u_int32_t plen, void *ctxt)
776: {
777: Authctxt *authctxt = ctxt;
778: gss_buffer_desc recv_tok;
1.130 markus 779: OM_uint32 status;
1.121 markus 780: u_int slen;
781:
782: if (authctxt == NULL)
783: fatal("input_gssapi_response: no authentication context");
784:
785: recv_tok.value = packet_get_string(&slen);
786: recv_tok.length = slen; /* safe typecast */
787:
788: packet_check_eom();
789:
1.130 markus 790: status = process_gssapi_token(ctxt, &recv_tok);
1.121 markus 791:
1.197 djm 792: free(recv_tok.value);
1.121 markus 793:
794: if (GSS_ERROR(status)) {
795: /* Start again with the next method in the list */
796: userauth(authctxt, NULL);
1.220 djm 797: return 0;
1.121 markus 798: }
1.220 djm 799: return 0;
1.121 markus 800: }
801:
1.169 djm 802: /* ARGSUSED */
1.220 djm 803: int
1.121 markus 804: input_gssapi_errtok(int type, u_int32_t plen, void *ctxt)
805: {
806: Authctxt *authctxt = ctxt;
807: Gssctxt *gssctxt;
808: gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
809: gss_buffer_desc recv_tok;
1.194 djm 810: OM_uint32 ms;
1.123 deraadt 811: u_int len;
1.121 markus 812:
813: if (authctxt == NULL)
814: fatal("input_gssapi_response: no authentication context");
815: gssctxt = authctxt->methoddata;
816:
1.123 deraadt 817: recv_tok.value = packet_get_string(&len);
818: recv_tok.length = len;
1.121 markus 819:
820: packet_check_eom();
821:
822: /* Stick it into GSSAPI and see what it says */
1.194 djm 823: (void)ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
1.140 djm 824: &recv_tok, &send_tok, NULL);
1.121 markus 825:
1.197 djm 826: free(recv_tok.value);
1.121 markus 827: gss_release_buffer(&ms, &send_tok);
828:
829: /* Server will be returning a failed packet after this one */
1.220 djm 830: return 0;
1.121 markus 831: }
832:
1.169 djm 833: /* ARGSUSED */
1.220 djm 834: int
1.121 markus 835: input_gssapi_error(int type, u_int32_t plen, void *ctxt)
836: {
837: char *msg;
838: char *lang;
839:
1.194 djm 840: /* maj */(void)packet_get_int();
841: /* min */(void)packet_get_int();
1.121 markus 842: msg=packet_get_string(NULL);
843: lang=packet_get_string(NULL);
844:
845: packet_check_eom();
846:
1.143 stevesk 847: debug("Server GSSAPI Error:\n%s", msg);
1.197 djm 848: free(msg);
849: free(lang);
1.220 djm 850: return 0;
1.121 markus 851: }
852: #endif /* GSSAPI */
1.20 markus 853:
1.1 markus 854: int
1.23 markus 855: userauth_none(Authctxt *authctxt)
856: {
857: /* initial userauth request */
858: packet_start(SSH2_MSG_USERAUTH_REQUEST);
859: packet_put_cstring(authctxt->server_user);
860: packet_put_cstring(authctxt->service);
861: packet_put_cstring(authctxt->method->name);
862: packet_send();
863: return 1;
864: }
865:
866: int
1.20 markus 867: userauth_passwd(Authctxt *authctxt)
1.1 markus 868: {
1.6 markus 869: static int attempt = 0;
1.99 markus 870: char prompt[150];
1.1 markus 871: char *password;
1.175 dtucker 872: const char *host = options.host_key_alias ? options.host_key_alias :
873: authctxt->host;
1.6 markus 874:
1.13 todd 875: if (attempt++ >= options.number_of_password_prompts)
1.6 markus 876: return 0;
1.13 todd 877:
1.87 deraadt 878: if (attempt != 1)
1.13 todd 879: error("Permission denied, please try again.");
1.1 markus 880:
1.43 itojun 881: snprintf(prompt, sizeof(prompt), "%.30s@%.128s's password: ",
1.175 dtucker 882: authctxt->server_user, host);
1.1 markus 883: password = read_passphrase(prompt, 0);
884: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1.20 markus 885: packet_put_cstring(authctxt->server_user);
886: packet_put_cstring(authctxt->service);
1.23 markus 887: packet_put_cstring(authctxt->method->name);
1.1 markus 888: packet_put_char(0);
1.49 markus 889: packet_put_cstring(password);
1.204 djm 890: explicit_bzero(password, strlen(password));
1.197 djm 891: free(password);
1.85 markus 892: packet_add_padding(64);
1.1 markus 893: packet_send();
1.99 markus 894:
1.104 deraadt 895: dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
1.99 markus 896: &input_userauth_passwd_changereq);
897:
1.1 markus 898: return 1;
899: }
1.169 djm 900:
1.99 markus 901: /*
902: * parse PASSWD_CHANGEREQ, prompt user and send SSH2_MSG_USERAUTH_REQUEST
903: */
1.169 djm 904: /* ARGSUSED */
1.218 markus 905: int
1.153 djm 906: input_userauth_passwd_changereq(int type, u_int32_t seqnr, void *ctxt)
1.99 markus 907: {
908: Authctxt *authctxt = ctxt;
909: char *info, *lang, *password = NULL, *retype = NULL;
910: char prompt[150];
1.175 dtucker 911: const char *host = options.host_key_alias ? options.host_key_alias :
912: authctxt->host;
1.99 markus 913:
914: debug2("input_userauth_passwd_changereq");
915:
916: if (authctxt == NULL)
917: fatal("input_userauth_passwd_changereq: "
918: "no authentication context");
919:
920: info = packet_get_string(NULL);
921: lang = packet_get_string(NULL);
922: if (strlen(info) > 0)
1.116 itojun 923: logit("%s", info);
1.197 djm 924: free(info);
925: free(lang);
1.99 markus 926: packet_start(SSH2_MSG_USERAUTH_REQUEST);
927: packet_put_cstring(authctxt->server_user);
928: packet_put_cstring(authctxt->service);
929: packet_put_cstring(authctxt->method->name);
930: packet_put_char(1); /* additional info */
1.104 deraadt 931: snprintf(prompt, sizeof(prompt),
1.99 markus 932: "Enter %.30s@%.128s's old password: ",
1.175 dtucker 933: authctxt->server_user, host);
1.99 markus 934: password = read_passphrase(prompt, 0);
935: packet_put_cstring(password);
1.204 djm 936: explicit_bzero(password, strlen(password));
1.197 djm 937: free(password);
1.99 markus 938: password = NULL;
939: while (password == NULL) {
1.104 deraadt 940: snprintf(prompt, sizeof(prompt),
1.99 markus 941: "Enter %.30s@%.128s's new password: ",
1.175 dtucker 942: authctxt->server_user, host);
1.99 markus 943: password = read_passphrase(prompt, RP_ALLOW_EOF);
944: if (password == NULL) {
945: /* bail out */
1.218 markus 946: return 0;
1.99 markus 947: }
1.104 deraadt 948: snprintf(prompt, sizeof(prompt),
1.99 markus 949: "Retype %.30s@%.128s's new password: ",
1.175 dtucker 950: authctxt->server_user, host);
1.99 markus 951: retype = read_passphrase(prompt, 0);
952: if (strcmp(password, retype) != 0) {
1.204 djm 953: explicit_bzero(password, strlen(password));
1.197 djm 954: free(password);
1.116 itojun 955: logit("Mismatch; try again, EOF to quit.");
1.99 markus 956: password = NULL;
957: }
1.204 djm 958: explicit_bzero(retype, strlen(retype));
1.197 djm 959: free(retype);
1.99 markus 960: }
961: packet_put_cstring(password);
1.204 djm 962: explicit_bzero(password, strlen(password));
1.197 djm 963: free(password);
1.99 markus 964: packet_add_padding(64);
965: packet_send();
1.104 deraadt 966:
967: dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
1.99 markus 968: &input_userauth_passwd_changereq);
1.218 markus 969: return 0;
1.117 markus 970: }
971:
972: static int
1.214 djm 973: identity_sign(struct identity *id, u_char **sigp, size_t *lenp,
974: const u_char *data, size_t datalen, u_int compat)
1.117 markus 975: {
976: Key *prv;
977: int ret;
1.99 markus 978:
1.117 markus 979: /* the agent supports this key */
1.214 djm 980: if (id->agent_fd)
981: return ssh_agent_sign(id->agent_fd, id->key, sigp, lenp,
982: data, datalen, compat);
983:
1.117 markus 984: /*
985: * we have already loaded the private key or
986: * the private key is stored in external hardware
987: */
1.209 djm 988: if (id->isprivate || (id->key->flags & SSHKEY_FLAG_EXT))
1.214 djm 989: return (sshkey_sign(id->key, sigp, lenp, data, datalen,
990: compat));
1.117 markus 991: /* load the private key from the file */
1.191 dtucker 992: if ((prv = load_identity_file(id->filename, id->userprovided)) == NULL)
1.214 djm 993: return (-1); /* XXX return decent error code */
994: ret = sshkey_sign(prv, sigp, lenp, data, datalen, compat);
995: sshkey_free(prv);
1.117 markus 996: return (ret);
1.51 markus 997: }
998:
1.76 itojun 999: static int
1.117 markus 1000: sign_and_send_pubkey(Authctxt *authctxt, Identity *id)
1.1 markus 1001: {
1002: Buffer b;
1.32 markus 1003: u_char *blob, *signature;
1.214 djm 1004: u_int bloblen;
1005: size_t slen;
1.120 markus 1006: u_int skip = 0;
1.17 markus 1007: int ret = -1;
1.23 markus 1008: int have_sig = 1;
1.182 djm 1009: char *fp;
1.1 markus 1010:
1.222 djm 1011: if ((fp = sshkey_fingerprint(id->key, options.fingerprint_hash,
1012: SSH_FP_DEFAULT)) == NULL)
1013: return 0;
1.182 djm 1014: debug3("sign_and_send_pubkey: %s %s", key_type(id->key), fp);
1.197 djm 1015: free(fp);
1.51 markus 1016:
1.117 markus 1017: if (key_to_blob(id->key, &blob, &bloblen) == 0) {
1.28 markus 1018: /* we cannot handle this key */
1.30 markus 1019: debug3("sign_and_send_pubkey: cannot handle key");
1.28 markus 1020: return 0;
1021: }
1.1 markus 1022: /* data to be signed */
1023: buffer_init(&b);
1.26 markus 1024: if (datafellows & SSH_OLD_SESSIONID) {
1025: buffer_append(&b, session_id2, session_id2_len);
1.41 stevesk 1026: skip = session_id2_len;
1.26 markus 1027: } else {
1.14 markus 1028: buffer_put_string(&b, session_id2, session_id2_len);
1029: skip = buffer_len(&b);
1030: }
1.1 markus 1031: buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
1.20 markus 1032: buffer_put_cstring(&b, authctxt->server_user);
1.10 markus 1033: buffer_put_cstring(&b,
1.30 markus 1034: datafellows & SSH_BUG_PKSERVICE ?
1.10 markus 1035: "ssh-userauth" :
1.20 markus 1036: authctxt->service);
1.30 markus 1037: if (datafellows & SSH_BUG_PKAUTH) {
1038: buffer_put_char(&b, have_sig);
1039: } else {
1040: buffer_put_cstring(&b, authctxt->method->name);
1041: buffer_put_char(&b, have_sig);
1.117 markus 1042: buffer_put_cstring(&b, key_ssh_name(id->key));
1.30 markus 1043: }
1.1 markus 1044: buffer_put_string(&b, blob, bloblen);
1045:
1046: /* generate signature */
1.117 markus 1047: ret = identity_sign(id, &signature, &slen,
1.214 djm 1048: buffer_ptr(&b), buffer_len(&b), datafellows);
1049: if (ret != 0) {
1.197 djm 1050: free(blob);
1.17 markus 1051: buffer_free(&b);
1052: return 0;
1053: }
1.28 markus 1054: #ifdef DEBUG_PK
1.1 markus 1055: buffer_dump(&b);
1056: #endif
1.30 markus 1057: if (datafellows & SSH_BUG_PKSERVICE) {
1.10 markus 1058: buffer_clear(&b);
1059: buffer_append(&b, session_id2, session_id2_len);
1.51 markus 1060: skip = session_id2_len;
1.10 markus 1061: buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
1.20 markus 1062: buffer_put_cstring(&b, authctxt->server_user);
1063: buffer_put_cstring(&b, authctxt->service);
1.23 markus 1064: buffer_put_cstring(&b, authctxt->method->name);
1065: buffer_put_char(&b, have_sig);
1.30 markus 1066: if (!(datafellows & SSH_BUG_PKAUTH))
1.117 markus 1067: buffer_put_cstring(&b, key_ssh_name(id->key));
1.10 markus 1068: buffer_put_string(&b, blob, bloblen);
1069: }
1.197 djm 1070: free(blob);
1.51 markus 1071:
1.1 markus 1072: /* append signature */
1073: buffer_put_string(&b, signature, slen);
1.197 djm 1074: free(signature);
1.1 markus 1075:
1076: /* skip session id and packet type */
1.14 markus 1077: if (buffer_len(&b) < skip + 1)
1.20 markus 1078: fatal("userauth_pubkey: internal error");
1.14 markus 1079: buffer_consume(&b, skip + 1);
1.1 markus 1080:
1081: /* put remaining data from buffer into packet */
1082: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1083: packet_put_raw(buffer_ptr(&b), buffer_len(&b));
1084: buffer_free(&b);
1085: packet_send();
1.17 markus 1086:
1087: return 1;
1.16 markus 1088: }
1089:
1.76 itojun 1090: static int
1.117 markus 1091: send_pubkey_test(Authctxt *authctxt, Identity *id)
1.20 markus 1092: {
1.51 markus 1093: u_char *blob;
1.97 markus 1094: u_int bloblen, have_sig = 0;
1.20 markus 1095:
1.51 markus 1096: debug3("send_pubkey_test");
1.16 markus 1097:
1.117 markus 1098: if (key_to_blob(id->key, &blob, &bloblen) == 0) {
1.51 markus 1099: /* we cannot handle this key */
1100: debug3("send_pubkey_test: cannot handle key");
1.16 markus 1101: return 0;
1102: }
1.51 markus 1103: /* register callback for USERAUTH_PK_OK message */
1104: dispatch_set(SSH2_MSG_USERAUTH_PK_OK, &input_userauth_pk_ok);
1105:
1106: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1107: packet_put_cstring(authctxt->server_user);
1108: packet_put_cstring(authctxt->service);
1109: packet_put_cstring(authctxt->method->name);
1110: packet_put_char(have_sig);
1111: if (!(datafellows & SSH_BUG_PKAUTH))
1.117 markus 1112: packet_put_cstring(key_ssh_name(id->key));
1.51 markus 1113: packet_put_string(blob, bloblen);
1.197 djm 1114: free(blob);
1.51 markus 1115: packet_send();
1116: return 1;
1117: }
1118:
1.76 itojun 1119: static Key *
1.191 dtucker 1120: load_identity_file(char *filename, int userprovided)
1.51 markus 1121: {
1122: Key *private;
1123: char prompt[300], *passphrase;
1.215 djm 1124: int r, perm_ok = 0, quit = 0, i;
1.52 markus 1125: struct stat st;
1.16 markus 1126:
1.52 markus 1127: if (stat(filename, &st) < 0) {
1.191 dtucker 1128: (userprovided ? logit : debug3)("no such identity: %s: %s",
1129: filename, strerror(errno));
1.52 markus 1130: return NULL;
1131: }
1.214 djm 1132: snprintf(prompt, sizeof prompt,
1133: "Enter passphrase for key '%.100s': ", filename);
1134: for (i = 0; i <= options.number_of_password_prompts; i++) {
1135: if (i == 0)
1136: passphrase = "";
1137: else {
1.20 markus 1138: passphrase = read_passphrase(prompt, 0);
1.214 djm 1139: if (*passphrase == '\0') {
1.20 markus 1140: debug2("no passphrase given, try next key");
1.214 djm 1141: free(passphrase);
1142: break;
1143: }
1144: }
1145: switch ((r = sshkey_load_private_type(KEY_UNSPEC, filename,
1146: passphrase, &private, NULL, &perm_ok))) {
1147: case 0:
1148: break;
1149: case SSH_ERR_KEY_WRONG_PASSPHRASE:
1150: if (options.batch_mode) {
1151: quit = 1;
1152: break;
1153: }
1.215 djm 1154: if (i != 0)
1155: debug2("bad passphrase given, try again...");
1.214 djm 1156: break;
1157: case SSH_ERR_SYSTEM_ERROR:
1158: if (errno == ENOENT) {
1159: debug2("Load key \"%s\": %s",
1160: filename, ssh_err(r));
1.51 markus 1161: quit = 1;
1.214 djm 1162: break;
1.20 markus 1163: }
1.214 djm 1164: /* FALLTHROUGH */
1165: default:
1166: error("Load key \"%s\": %s", filename, ssh_err(r));
1167: quit = 1;
1168: break;
1169: }
1170: if (i > 0) {
1.204 djm 1171: explicit_bzero(passphrase, strlen(passphrase));
1.197 djm 1172: free(passphrase);
1.16 markus 1173: }
1.214 djm 1174: if (private != NULL || quit)
1175: break;
1.16 markus 1176: }
1.51 markus 1177: return private;
1178: }
1179:
1.117 markus 1180: /*
1181: * try keys in the following order:
1182: * 1. agent keys that are found in the config file
1183: * 2. other agent keys
1184: * 3. keys that are only listed in the config file
1185: */
1186: static void
1187: pubkey_prepare(Authctxt *authctxt)
1.51 markus 1188: {
1.214 djm 1189: struct identity *id, *id2, *tmp;
1190: struct idlist agent, files, *preferred;
1191: struct sshkey *key;
1192: int agent_fd, i, r, found;
1193: size_t j;
1194: struct ssh_identitylist *idlist;
1.51 markus 1195:
1.117 markus 1196: TAILQ_INIT(&agent); /* keys from the agent */
1197: TAILQ_INIT(&files); /* keys from the config file */
1198: preferred = &authctxt->keys;
1199: TAILQ_INIT(preferred); /* preferred order of keys */
1200:
1.190 djm 1201: /* list of keys stored in the filesystem and PKCS#11 */
1.117 markus 1202: for (i = 0; i < options.num_identity_files; i++) {
1203: key = options.identity_keys[i];
1204: if (key && key->type == KEY_RSA1)
1.180 djm 1205: continue;
1206: if (key && key->cert && key->cert->type != SSH2_CERT_TYPE_USER)
1.117 markus 1207: continue;
1208: options.identity_keys[i] = NULL;
1.150 djm 1209: id = xcalloc(1, sizeof(*id));
1.117 markus 1210: id->key = key;
1211: id->filename = xstrdup(options.identity_files[i]);
1.192 dtucker 1212: id->userprovided = options.identity_file_userprovided[i];
1.117 markus 1213: TAILQ_INSERT_TAIL(&files, id, next);
1.190 djm 1214: }
1215: /* Prefer PKCS11 keys that are explicitly listed */
1216: TAILQ_FOREACH_SAFE(id, &files, next, tmp) {
1.209 djm 1217: if (id->key == NULL || (id->key->flags & SSHKEY_FLAG_EXT) == 0)
1.190 djm 1218: continue;
1219: found = 0;
1220: TAILQ_FOREACH(id2, &files, next) {
1221: if (id2->key == NULL ||
1.209 djm 1222: (id2->key->flags & SSHKEY_FLAG_EXT) == 0)
1.190 djm 1223: continue;
1.214 djm 1224: if (sshkey_equal(id->key, id2->key)) {
1.190 djm 1225: TAILQ_REMOVE(&files, id, next);
1226: TAILQ_INSERT_TAIL(preferred, id, next);
1227: found = 1;
1228: break;
1229: }
1230: }
1231: /* If IdentitiesOnly set and key not found then don't use it */
1232: if (!found && options.identities_only) {
1233: TAILQ_REMOVE(&files, id, next);
1.203 tedu 1234: explicit_bzero(id, sizeof(*id));
1.190 djm 1235: free(id);
1236: }
1.117 markus 1237: }
1238: /* list of keys supported by the agent */
1.214 djm 1239: if ((r = ssh_get_authentication_socket(&agent_fd)) != 0) {
1240: if (r != SSH_ERR_AGENT_NOT_PRESENT)
1241: debug("%s: ssh_get_authentication_socket: %s",
1242: __func__, ssh_err(r));
1243: } else if ((r = ssh_fetch_identitylist(agent_fd, 2, &idlist)) != 0) {
1244: if (r != SSH_ERR_AGENT_NO_IDENTITIES)
1245: debug("%s: ssh_fetch_identitylist: %s",
1246: __func__, ssh_err(r));
1247: } else {
1248: for (j = 0; j < idlist->nkeys; j++) {
1.117 markus 1249: found = 0;
1250: TAILQ_FOREACH(id, &files, next) {
1.214 djm 1251: /*
1252: * agent keys from the config file are
1253: * preferred
1254: */
1255: if (sshkey_equal(idlist->keys[j], id->key)) {
1.117 markus 1256: TAILQ_REMOVE(&files, id, next);
1257: TAILQ_INSERT_TAIL(preferred, id, next);
1.214 djm 1258: id->agent_fd = agent_fd;
1.117 markus 1259: found = 1;
1260: break;
1261: }
1262: }
1.135 markus 1263: if (!found && !options.identities_only) {
1.150 djm 1264: id = xcalloc(1, sizeof(*id));
1.214 djm 1265: /* XXX "steals" key/comment from idlist */
1266: id->key = idlist->keys[j];
1267: id->filename = idlist->comments[j];
1268: idlist->keys[j] = NULL;
1269: idlist->comments[j] = NULL;
1270: id->agent_fd = agent_fd;
1.117 markus 1271: TAILQ_INSERT_TAIL(&agent, id, next);
1272: }
1273: }
1.214 djm 1274: ssh_free_identitylist(idlist);
1.117 markus 1275: /* append remaining agent keys */
1276: for (id = TAILQ_FIRST(&agent); id; id = TAILQ_FIRST(&agent)) {
1277: TAILQ_REMOVE(&agent, id, next);
1278: TAILQ_INSERT_TAIL(preferred, id, next);
1279: }
1.214 djm 1280: authctxt->agent_fd = agent_fd;
1.117 markus 1281: }
1282: /* append remaining keys from the config file */
1283: for (id = TAILQ_FIRST(&files); id; id = TAILQ_FIRST(&files)) {
1284: TAILQ_REMOVE(&files, id, next);
1285: TAILQ_INSERT_TAIL(preferred, id, next);
1286: }
1287: TAILQ_FOREACH(id, preferred, next) {
1.191 dtucker 1288: debug2("key: %s (%p),%s", id->filename, id->key,
1289: id->userprovided ? " explicit" : "");
1.117 markus 1290: }
1.17 markus 1291: }
1292:
1.117 markus 1293: static void
1294: pubkey_cleanup(Authctxt *authctxt)
1.51 markus 1295: {
1.117 markus 1296: Identity *id;
1.51 markus 1297:
1.214 djm 1298: if (authctxt->agent_fd != -1)
1299: ssh_close_authentication_socket(authctxt->agent_fd);
1.117 markus 1300: for (id = TAILQ_FIRST(&authctxt->keys); id;
1301: id = TAILQ_FIRST(&authctxt->keys)) {
1302: TAILQ_REMOVE(&authctxt->keys, id, next);
1303: if (id->key)
1.214 djm 1304: sshkey_free(id->key);
1.197 djm 1305: free(id->filename);
1306: free(id);
1.117 markus 1307: }
1.1 markus 1308: }
1309:
1.20 markus 1310: int
1311: userauth_pubkey(Authctxt *authctxt)
1312: {
1.117 markus 1313: Identity *id;
1.20 markus 1314: int sent = 0;
1315:
1.117 markus 1316: while ((id = TAILQ_FIRST(&authctxt->keys))) {
1317: if (id->tried++)
1318: return (0);
1.127 markus 1319: /* move key to the end of the queue */
1.117 markus 1320: TAILQ_REMOVE(&authctxt->keys, id, next);
1321: TAILQ_INSERT_TAIL(&authctxt->keys, id, next);
1322: /*
1323: * send a test message if we have the public key. for
1324: * encrypted keys we cannot do this and have to load the
1325: * private key instead
1326: */
1.200 djm 1327: if (id->key != NULL) {
1328: if (key_type_plain(id->key->type) == KEY_RSA &&
1329: (datafellows & SSH_BUG_RSASIGMD5) != 0) {
1330: debug("Skipped %s key %s for RSA/MD5 server",
1331: key_type(id->key), id->filename);
1332: } else if (id->key->type != KEY_RSA1) {
1333: debug("Offering %s public key: %s",
1334: key_type(id->key), id->filename);
1335: sent = send_pubkey_test(authctxt, id);
1336: }
1337: } else {
1.117 markus 1338: debug("Trying private key: %s", id->filename);
1.191 dtucker 1339: id->key = load_identity_file(id->filename,
1340: id->userprovided);
1.117 markus 1341: if (id->key != NULL) {
1342: id->isprivate = 1;
1.200 djm 1343: if (key_type_plain(id->key->type) == KEY_RSA &&
1344: (datafellows & SSH_BUG_RSASIGMD5) != 0) {
1345: debug("Skipped %s key %s for RSA/MD5 "
1346: "server", key_type(id->key),
1347: id->filename);
1348: } else {
1349: sent = sign_and_send_pubkey(
1350: authctxt, id);
1351: }
1.117 markus 1352: key_free(id->key);
1353: id->key = NULL;
1.51 markus 1354: }
1355: }
1.117 markus 1356: if (sent)
1357: return (sent);
1.28 markus 1358: }
1.117 markus 1359: return (0);
1.20 markus 1360: }
1361:
1.23 markus 1362: /*
1363: * Send userauth request message specifying keyboard-interactive method.
1364: */
1365: int
1366: userauth_kbdint(Authctxt *authctxt)
1367: {
1368: static int attempt = 0;
1369:
1370: if (attempt++ >= options.number_of_password_prompts)
1371: return 0;
1.82 markus 1372: /* disable if no SSH2_MSG_USERAUTH_INFO_REQUEST has been seen */
1373: if (attempt > 1 && !authctxt->info_req_seen) {
1374: debug3("userauth_kbdint: disable: no info_req_seen");
1375: dispatch_set(SSH2_MSG_USERAUTH_INFO_REQUEST, NULL);
1376: return 0;
1377: }
1.23 markus 1378:
1379: debug2("userauth_kbdint");
1380: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1381: packet_put_cstring(authctxt->server_user);
1382: packet_put_cstring(authctxt->service);
1383: packet_put_cstring(authctxt->method->name);
1384: packet_put_cstring(""); /* lang */
1385: packet_put_cstring(options.kbd_interactive_devices ?
1386: options.kbd_interactive_devices : "");
1387: packet_send();
1388:
1389: dispatch_set(SSH2_MSG_USERAUTH_INFO_REQUEST, &input_userauth_info_req);
1390: return 1;
1391: }
1392:
1393: /*
1.46 markus 1394: * parse INFO_REQUEST, prompt user and send INFO_RESPONSE
1.23 markus 1395: */
1.218 markus 1396: int
1.92 markus 1397: input_userauth_info_req(int type, u_int32_t seq, void *ctxt)
1.23 markus 1398: {
1399: Authctxt *authctxt = ctxt;
1.46 markus 1400: char *name, *inst, *lang, *prompt, *response;
1.32 markus 1401: u_int num_prompts, i;
1.23 markus 1402: int echo = 0;
1403:
1404: debug2("input_userauth_info_req");
1405:
1406: if (authctxt == NULL)
1407: fatal("input_userauth_info_req: no authentication context");
1.82 markus 1408:
1409: authctxt->info_req_seen = 1;
1.23 markus 1410:
1411: name = packet_get_string(NULL);
1412: inst = packet_get_string(NULL);
1413: lang = packet_get_string(NULL);
1414: if (strlen(name) > 0)
1.116 itojun 1415: logit("%s", name);
1.23 markus 1416: if (strlen(inst) > 0)
1.116 itojun 1417: logit("%s", inst);
1.197 djm 1418: free(name);
1419: free(inst);
1420: free(lang);
1.23 markus 1421:
1422: num_prompts = packet_get_int();
1423: /*
1424: * Begin to build info response packet based on prompts requested.
1425: * We commit to providing the correct number of responses, so if
1426: * further on we run into a problem that prevents this, we have to
1427: * be sure and clean this up and send a correct error response.
1428: */
1429: packet_start(SSH2_MSG_USERAUTH_INFO_RESPONSE);
1430: packet_put_int(num_prompts);
1431:
1.73 markus 1432: debug2("input_userauth_info_req: num_prompts %d", num_prompts);
1.23 markus 1433: for (i = 0; i < num_prompts; i++) {
1434: prompt = packet_get_string(NULL);
1435: echo = packet_get_char();
1436:
1.77 markus 1437: response = read_passphrase(prompt, echo ? RP_ECHO : 0);
1.23 markus 1438:
1.49 markus 1439: packet_put_cstring(response);
1.204 djm 1440: explicit_bzero(response, strlen(response));
1.197 djm 1441: free(response);
1442: free(prompt);
1.23 markus 1443: }
1.90 markus 1444: packet_check_eom(); /* done with parsing incoming message. */
1.23 markus 1445:
1.85 markus 1446: packet_add_padding(64);
1.23 markus 1447: packet_send();
1.218 markus 1448: return 0;
1.68 markus 1449: }
1450:
1.100 markus 1451: static int
1.223 ! djm 1452: ssh_keysign(struct sshkey *key, u_char **sigp, size_t *lenp,
! 1453: const u_char *data, size_t datalen)
1.100 markus 1454: {
1.223 ! djm 1455: struct sshbuf *b;
1.101 markus 1456: struct stat st;
1.100 markus 1457: pid_t pid;
1.223 ! djm 1458: int i, r, to[2], from[2], status, sock = packet_get_connection_in();
! 1459: u_char rversion = 0, version = 2;
! 1460: void (*osigchld)(int);
1.100 markus 1461:
1.223 ! djm 1462: *sigp = NULL;
! 1463: *lenp = 0;
1.100 markus 1464:
1.101 markus 1465: if (stat(_PATH_SSH_KEY_SIGN, &st) < 0) {
1.223 ! djm 1466: error("%s: not installed: %s", __func__, strerror(errno));
! 1467: return -1;
! 1468: }
! 1469: if (fflush(stdout) != 0) {
! 1470: error("%s: fflush: %s", __func__, strerror(errno));
1.101 markus 1471: return -1;
1472: }
1.100 markus 1473: if (pipe(to) < 0) {
1.223 ! djm 1474: error("%s: pipe: %s", __func__, strerror(errno));
1.100 markus 1475: return -1;
1476: }
1477: if (pipe(from) < 0) {
1.223 ! djm 1478: error("%s: pipe: %s", __func__, strerror(errno));
1.100 markus 1479: return -1;
1480: }
1481: if ((pid = fork()) < 0) {
1.223 ! djm 1482: error("%s: fork: %s", __func__, strerror(errno));
1.100 markus 1483: return -1;
1484: }
1.223 ! djm 1485: osigchld = signal(SIGCHLD, SIG_DFL);
1.100 markus 1486: if (pid == 0) {
1.174 dtucker 1487: /* keep the socket on exec */
1.223 ! djm 1488: fcntl(sock, F_SETFD, 0);
1.155 markus 1489: permanently_drop_suid(getuid());
1.100 markus 1490: close(from[0]);
1491: if (dup2(from[1], STDOUT_FILENO) < 0)
1.223 ! djm 1492: fatal("%s: dup2: %s", __func__, strerror(errno));
1.100 markus 1493: close(to[1]);
1494: if (dup2(to[0], STDIN_FILENO) < 0)
1.223 ! djm 1495: fatal("%s: dup2: %s", __func__, strerror(errno));
1.103 markus 1496: close(from[1]);
1497: close(to[0]);
1.223 ! djm 1498: /* Close everything but stdio and the socket */
! 1499: for (i = STDERR_FILENO + 1; i < sock; i++)
! 1500: close(i);
! 1501: closefrom(sock + 1);
! 1502: debug3("%s: [child] pid=%ld, exec %s",
! 1503: __func__, (long)getpid(), _PATH_SSH_KEY_SIGN);
1.102 markus 1504: execl(_PATH_SSH_KEY_SIGN, _PATH_SSH_KEY_SIGN, (char *) 0);
1.223 ! djm 1505: fatal("%s: exec(%s): %s", __func__, _PATH_SSH_KEY_SIGN,
1.100 markus 1506: strerror(errno));
1507: }
1508: close(from[1]);
1509: close(to[0]);
1510:
1.223 ! djm 1511: if ((b = sshbuf_new()) == NULL)
! 1512: fatal("%s: sshbuf_new failed", __func__);
! 1513: /* send # of sock, data to be signed */
! 1514: if ((r = sshbuf_put_u32(b, sock) != 0) ||
! 1515: (r = sshbuf_put_string(b, data, datalen)) != 0)
! 1516: fatal("%s: buffer error: %s", __func__, ssh_err(r));
! 1517: if (ssh_msg_send(to[1], version, b) == -1)
! 1518: fatal("%s: couldn't send request", __func__);
! 1519: sshbuf_reset(b);
! 1520: r = ssh_msg_recv(from[0], b);
1.101 markus 1521: close(from[0]);
1522: close(to[1]);
1.223 ! djm 1523: if (r < 0) {
! 1524: error("%s: no reply", __func__);
! 1525: goto fail;
! 1526: }
1.101 markus 1527:
1.223 ! djm 1528: errno = 0;
! 1529: while (waitpid(pid, &status, 0) < 0) {
! 1530: if (errno != EINTR) {
! 1531: error("%s: waitpid %ld: %s",
! 1532: __func__, (long)pid, strerror(errno));
! 1533: goto fail;
! 1534: }
! 1535: }
! 1536: if (!WIFEXITED(status)) {
! 1537: error("%s: exited abnormally", __func__);
! 1538: goto fail;
! 1539: }
! 1540: if (WEXITSTATUS(status) != 0) {
! 1541: error("%s: exited with status %d",
! 1542: __func__, WEXITSTATUS(status));
! 1543: goto fail;
! 1544: }
! 1545: if ((r = sshbuf_get_u8(b, &rversion)) != 0) {
! 1546: error("%s: buffer error: %s", __func__, ssh_err(r));
! 1547: goto fail;
! 1548: }
! 1549: if (rversion != version) {
! 1550: error("%s: bad version", __func__);
! 1551: goto fail;
! 1552: }
! 1553: if ((r = sshbuf_get_string(b, sigp, lenp)) != 0) {
! 1554: error("%s: buffer error: %s", __func__, ssh_err(r));
! 1555: fail:
! 1556: signal(SIGCHLD, osigchld);
! 1557: sshbuf_free(b);
1.100 markus 1558: return -1;
1559: }
1.223 ! djm 1560: signal(SIGCHLD, osigchld);
! 1561: sshbuf_free(b);
1.100 markus 1562:
1563: return 0;
1564: }
1565:
1.68 markus 1566: int
1567: userauth_hostbased(Authctxt *authctxt)
1568: {
1.223 ! djm 1569: struct ssh *ssh = active_state;
! 1570: struct sshkey *private = NULL;
! 1571: struct sshbuf *b = NULL;
1.72 markus 1572: const char *service;
1.223 ! djm 1573: u_char *sig = NULL, *keyblob = NULL;
! 1574: char *fp = NULL, *chost = NULL, *lname = NULL;
! 1575: size_t siglen = 0, keylen = 0;
! 1576: int i, r, success = 0;
! 1577:
! 1578: if (authctxt->ktypes == NULL) {
! 1579: authctxt->oktypes = xstrdup(options.hostbased_key_types);
! 1580: authctxt->ktypes = authctxt->oktypes;
! 1581: }
1.213 djm 1582:
1.223 ! djm 1583: /*
! 1584: * Work through each listed type pattern in HostbasedKeyTypes,
! 1585: * trying each hostkey that matches the type in turn.
! 1586: */
! 1587: for (;;) {
! 1588: if (authctxt->active_ktype == NULL)
! 1589: authctxt->active_ktype = strsep(&authctxt->ktypes, ",");
! 1590: if (authctxt->active_ktype == NULL ||
! 1591: *authctxt->active_ktype == '\0')
! 1592: break;
! 1593: debug3("%s: trying key type %s", __func__,
! 1594: authctxt->active_ktype);
1.68 markus 1595:
1.223 ! djm 1596: /* check for a useful key */
! 1597: private = NULL;
! 1598: for (i = 0; i < authctxt->sensitive->nkeys; i++) {
! 1599: if (authctxt->sensitive->keys[i] == NULL ||
! 1600: authctxt->sensitive->keys[i]->type == KEY_RSA1 ||
! 1601: authctxt->sensitive->keys[i]->type == KEY_UNSPEC)
! 1602: continue;
! 1603: if (match_pattern_list(
! 1604: sshkey_ssh_name(authctxt->sensitive->keys[i]),
! 1605: authctxt->active_ktype,
! 1606: strlen(authctxt->active_ktype), 0) != 1)
! 1607: continue;
1.68 markus 1608: /* we take and free the key */
1.223 ! djm 1609: private = authctxt->sensitive->keys[i];
! 1610: authctxt->sensitive->keys[i] = NULL;
1.68 markus 1611: break;
1612: }
1.223 ! djm 1613: /* Found one */
! 1614: if (private != NULL)
! 1615: break;
! 1616: /* No more keys of this type; advance */
! 1617: authctxt->active_ktype = NULL;
1.68 markus 1618: }
1.223 ! djm 1619: if (private == NULL) {
! 1620: free(authctxt->oktypes);
! 1621: authctxt->oktypes = authctxt->ktypes = NULL;
! 1622: authctxt->active_ktype = NULL;
1.109 markus 1623: debug("No more client hostkeys for hostbased authentication.");
1.223 ! djm 1624: goto out;
1.68 markus 1625: }
1.211 djm 1626:
1.223 ! djm 1627: if ((fp = sshkey_fingerprint(private, options.fingerprint_hash,
! 1628: SSH_FP_DEFAULT)) == NULL) {
! 1629: error("%s: sshkey_fingerprint failed", __func__);
! 1630: goto out;
1.68 markus 1631: }
1.223 ! djm 1632: debug("%s: trying hostkey %s %s",
! 1633: __func__, sshkey_ssh_name(private), fp);
1.211 djm 1634:
1.84 markus 1635: /* figure out a name for the client host */
1.223 ! djm 1636: if ((lname = get_local_name(packet_get_connection_in())) == NULL) {
! 1637: error("%s: cannot get local ipaddr/name", __func__);
! 1638: goto out;
1.84 markus 1639: }
1.223 ! djm 1640:
! 1641: /* XXX sshbuf_put_stringf? */
! 1642: xasprintf(&chost, "%s.", lname);
! 1643: debug2("%s: chost %s", __func__, chost);
1.84 markus 1644:
1.72 markus 1645: service = datafellows & SSH_BUG_HBSERVICE ? "ssh-userauth" :
1646: authctxt->service;
1.223 ! djm 1647:
1.68 markus 1648: /* construct data */
1.223 ! djm 1649: if ((b = sshbuf_new()) == NULL) {
! 1650: error("%s: sshbuf_new failed", __func__);
! 1651: goto out;
! 1652: }
! 1653: if ((r = sshkey_to_blob(private, &keyblob, &keylen)) != 0) {
! 1654: error("%s: sshkey_to_blob: %s", __func__, ssh_err(r));
! 1655: goto out;
! 1656: }
! 1657: if ((r = sshbuf_put_string(b, session_id2, session_id2_len)) != 0 ||
! 1658: (r = sshbuf_put_u8(b, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
! 1659: (r = sshbuf_put_cstring(b, authctxt->server_user)) != 0 ||
! 1660: (r = sshbuf_put_cstring(b, service)) != 0 ||
! 1661: (r = sshbuf_put_cstring(b, authctxt->method->name)) != 0 ||
! 1662: (r = sshbuf_put_cstring(b, key_ssh_name(private))) != 0 ||
! 1663: (r = sshbuf_put_string(b, keyblob, keylen)) != 0 ||
! 1664: (r = sshbuf_put_cstring(b, chost)) != 0 ||
! 1665: (r = sshbuf_put_cstring(b, authctxt->local_user)) != 0) {
! 1666: error("%s: buffer error: %s", __func__, ssh_err(r));
! 1667: goto out;
! 1668: }
! 1669:
1.68 markus 1670: #ifdef DEBUG_PK
1.223 ! djm 1671: sshbuf_dump(b, stderr);
1.68 markus 1672: #endif
1.223 ! djm 1673: if (authctxt->sensitive->external_keysign)
! 1674: r = ssh_keysign(private, &sig, &siglen,
! 1675: sshbuf_ptr(b), sshbuf_len(b));
! 1676: else if ((r = sshkey_sign(private, &sig, &siglen,
! 1677: sshbuf_ptr(b), sshbuf_len(b), datafellows)) != 0)
! 1678: debug("%s: sshkey_sign: %s", __func__, ssh_err(r));
! 1679: if (r != 0) {
! 1680: error("sign using hostkey %s %s failed",
! 1681: sshkey_ssh_name(private), fp);
! 1682: goto out;
! 1683: }
! 1684: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
! 1685: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
! 1686: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
! 1687: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
! 1688: (r = sshpkt_put_cstring(ssh, key_ssh_name(private))) != 0 ||
! 1689: (r = sshpkt_put_string(ssh, keyblob, keylen)) != 0 ||
! 1690: (r = sshpkt_put_cstring(ssh, chost)) != 0 ||
! 1691: (r = sshpkt_put_cstring(ssh, authctxt->local_user)) != 0 ||
! 1692: (r = sshpkt_put_string(ssh, sig, siglen)) != 0 ||
! 1693: (r = sshpkt_send(ssh)) != 0) {
! 1694: error("%s: packet error: %s", __func__, ssh_err(r));
! 1695: goto out;
! 1696: }
! 1697: success = 1;
! 1698:
! 1699: out:
! 1700: if (sig != NULL) {
! 1701: explicit_bzero(sig, siglen);
! 1702: free(sig);
1.68 markus 1703: }
1.223 ! djm 1704: free(keyblob);
! 1705: free(lname);
! 1706: free(fp);
1.197 djm 1707: free(chost);
1.223 ! djm 1708: sshkey_free(private);
! 1709: sshbuf_free(b);
1.68 markus 1710:
1.223 ! djm 1711: return success;
1.23 markus 1712: }
1.170 djm 1713:
1.20 markus 1714: /* find auth method */
1715:
1716: /*
1717: * given auth method name, if configurable options permit this method fill
1718: * in auth_ident field and return true, otherwise return false.
1719: */
1.76 itojun 1720: static int
1.20 markus 1721: authmethod_is_enabled(Authmethod *method)
1722: {
1723: if (method == NULL)
1724: return 0;
1725: /* return false if options indicate this method is disabled */
1726: if (method->enabled == NULL || *method->enabled == 0)
1727: return 0;
1728: /* return false if batch mode is enabled but method needs interactive mode */
1729: if (method->batch_flag != NULL && *method->batch_flag != 0)
1730: return 0;
1731: return 1;
1732: }
1733:
1.76 itojun 1734: static Authmethod *
1.20 markus 1735: authmethod_lookup(const char *name)
1.1 markus 1736: {
1.20 markus 1737: Authmethod *method = NULL;
1738: if (name != NULL)
1739: for (method = authmethods; method->name != NULL; method++)
1740: if (strcmp(name, method->name) == 0)
1741: return method;
1742: debug2("Unrecognized authentication method name: %s", name ? name : "NULL");
1743: return NULL;
1744: }
1.1 markus 1745:
1.53 markus 1746: /* XXX internal state */
1747: static Authmethod *current = NULL;
1748: static char *supported = NULL;
1749: static char *preferred = NULL;
1.105 deraadt 1750:
1.20 markus 1751: /*
1752: * Given the authentication method list sent by the server, return the
1753: * next method we should try. If the server initially sends a nil list,
1.67 markus 1754: * use a built-in default list.
1.41 stevesk 1755: */
1.76 itojun 1756: static Authmethod *
1.20 markus 1757: authmethod_get(char *authlist)
1758: {
1.53 markus 1759: char *name = NULL;
1.97 markus 1760: u_int next;
1.41 stevesk 1761:
1.20 markus 1762: /* Use a suitable default if we're passed a nil list. */
1763: if (authlist == NULL || strlen(authlist) == 0)
1.53 markus 1764: authlist = options.preferred_authentications;
1.20 markus 1765:
1.53 markus 1766: if (supported == NULL || strcmp(authlist, supported) != 0) {
1767: debug3("start over, passed a different list %s", authlist);
1.197 djm 1768: free(supported);
1.53 markus 1769: supported = xstrdup(authlist);
1770: preferred = options.preferred_authentications;
1771: debug3("preferred %s", preferred);
1772: current = NULL;
1773: } else if (current != NULL && authmethod_is_enabled(current))
1774: return current;
1.20 markus 1775:
1.53 markus 1776: for (;;) {
1777: if ((name = match_list(preferred, supported, &next)) == NULL) {
1.109 markus 1778: debug("No more authentication methods to try.");
1.53 markus 1779: current = NULL;
1780: return NULL;
1781: }
1782: preferred += next;
1.23 markus 1783: debug3("authmethod_lookup %s", name);
1.53 markus 1784: debug3("remaining preferred: %s", preferred);
1785: if ((current = authmethod_lookup(name)) != NULL &&
1786: authmethod_is_enabled(current)) {
1.23 markus 1787: debug3("authmethod_is_enabled %s", name);
1.109 markus 1788: debug("Next authentication method: %s", name);
1.197 djm 1789: free(name);
1.53 markus 1790: return current;
1.23 markus 1791: }
1.198 dtucker 1792: free(name);
1.1 markus 1793: }
1.53 markus 1794: }
1.1 markus 1795:
1.79 stevesk 1796: static char *
1.53 markus 1797: authmethods_get(void)
1798: {
1799: Authmethod *method = NULL;
1.93 markus 1800: Buffer b;
1801: char *list;
1.27 provos 1802:
1.93 markus 1803: buffer_init(&b);
1.53 markus 1804: for (method = authmethods; method->name != NULL; method++) {
1805: if (authmethod_is_enabled(method)) {
1.93 markus 1806: if (buffer_len(&b) > 0)
1807: buffer_append(&b, ",", 1);
1808: buffer_append(&b, method->name, strlen(method->name));
1.53 markus 1809: }
1810: }
1.93 markus 1811: buffer_append(&b, "\0", 1);
1812: list = xstrdup(buffer_ptr(&b));
1813: buffer_free(&b);
1814: return list;
1.1 markus 1815: }
1.170 djm 1816:
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