Annotation of src/usr.bin/ssh/sshconnect2.c, Revision 1.187
1.187 ! djm 1: /* $OpenBSD: sshconnect2.c,v 1.186 2010/11/29 23:45:51 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"
58: #include "readconf.h"
1.137 djm 59: #include "misc.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"
1.171 djm 67: #include "schnorr.h"
1.170 djm 68: #include "jpake.h"
1.22 provos 69:
1.121 markus 70: #ifdef GSSAPI
71: #include "ssh-gss.h"
72: #endif
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:
1.63 markus 89: Kex *xxx_kex = NULL;
90:
1.76 itojun 91: static int
1.75 markus 92: verify_host_key_callback(Key *hostkey)
1.61 markus 93: {
1.75 markus 94: if (verify_host_key(xxx_host, xxx_hostaddr, hostkey) == -1)
1.83 markus 95: fatal("Host key verification failed.");
1.61 markus 96: return 0;
97: }
98:
1.186 djm 99: static char *
100: order_hostkeyalgs(char *host, struct sockaddr *hostaddr, u_short port)
101: {
102: char *oavail, *avail, *first, *last, *alg, *hostname, *ret;
103: size_t maxlen;
104: struct hostkeys *hostkeys;
105: int ktype;
106:
107: /* Find all hostkeys for this hostname */
108: get_hostfile_hostname_ipaddr(host, hostaddr, port, &hostname, NULL);
109: hostkeys = init_hostkeys();
110: load_hostkeys(hostkeys, hostname, options.user_hostfile2);
111: load_hostkeys(hostkeys, hostname, options.system_hostfile2);
112: load_hostkeys(hostkeys, hostname, options.user_hostfile);
113: load_hostkeys(hostkeys, hostname, options.system_hostfile);
114:
115: oavail = avail = xstrdup(KEX_DEFAULT_PK_ALG);
116: maxlen = strlen(avail) + 1;
117: first = xmalloc(maxlen);
118: last = xmalloc(maxlen);
119: *first = *last = '\0';
120:
121: #define ALG_APPEND(to, from) \
122: do { \
123: if (*to != '\0') \
124: strlcat(to, ",", maxlen); \
125: strlcat(to, from, maxlen); \
126: } while (0)
127:
128: while ((alg = strsep(&avail, ",")) && *alg != '\0') {
129: if ((ktype = key_type_from_name(alg)) == KEY_UNSPEC)
130: fatal("%s: unknown alg %s", __func__, alg);
131: if (lookup_key_in_hostkeys_by_type(hostkeys,
132: key_type_plain(ktype), NULL))
133: ALG_APPEND(first, alg);
134: else
135: ALG_APPEND(last, alg);
136: }
137: #undef ALG_APPEND
138: xasprintf(&ret, "%s%s%s", first, *first == '\0' ? "" : ",", last);
139: if (*first != '\0')
140: debug3("%s: prefer hostkeyalgs: %s", __func__, first);
141:
142: xfree(first);
143: xfree(last);
144: xfree(hostname);
145: xfree(oavail);
146: free_hostkeys(hostkeys);
147:
148: return ret;
149: }
150:
1.1 markus 151: void
1.186 djm 152: ssh_kex2(char *host, struct sockaddr *hostaddr, u_short port)
1.22 provos 153: {
154: Kex *kex;
1.61 markus 155:
156: xxx_host = host;
157: xxx_hostaddr = hostaddr;
1.22 provos 158:
1.29 markus 159: if (options.ciphers == (char *)-1) {
1.116 itojun 160: logit("No valid ciphers for protocol version 2 given, using defaults.");
1.29 markus 161: options.ciphers = NULL;
1.24 markus 162: }
1.22 provos 163: if (options.ciphers != NULL) {
164: myproposal[PROPOSAL_ENC_ALGS_CTOS] =
165: myproposal[PROPOSAL_ENC_ALGS_STOC] = options.ciphers;
166: }
1.60 stevesk 167: myproposal[PROPOSAL_ENC_ALGS_CTOS] =
168: compat_cipher_proposal(myproposal[PROPOSAL_ENC_ALGS_CTOS]);
169: myproposal[PROPOSAL_ENC_ALGS_STOC] =
170: compat_cipher_proposal(myproposal[PROPOSAL_ENC_ALGS_STOC]);
1.22 provos 171: if (options.compression) {
1.47 markus 172: myproposal[PROPOSAL_COMP_ALGS_CTOS] =
1.141 markus 173: myproposal[PROPOSAL_COMP_ALGS_STOC] = "zlib@openssh.com,zlib,none";
1.22 provos 174: } else {
1.47 markus 175: myproposal[PROPOSAL_COMP_ALGS_CTOS] =
1.141 markus 176: myproposal[PROPOSAL_COMP_ALGS_STOC] = "none,zlib@openssh.com,zlib";
1.47 markus 177: }
178: if (options.macs != NULL) {
179: myproposal[PROPOSAL_MAC_ALGS_CTOS] =
180: myproposal[PROPOSAL_MAC_ALGS_STOC] = options.macs;
1.22 provos 181: }
1.70 markus 182: if (options.hostkeyalgorithms != NULL)
1.88 deraadt 183: myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] =
1.70 markus 184: options.hostkeyalgorithms;
1.186 djm 185: else {
186: /* Prefer algorithms that we already have keys for */
187: myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] =
188: order_hostkeyalgs(host, hostaddr, port);
189: }
1.185 djm 190: if (options.kex_algorithms != NULL)
191: myproposal[PROPOSAL_KEX_ALGS] = options.kex_algorithms;
1.115 markus 192:
193: if (options.rekey_limit)
1.165 djm 194: packet_set_rekey_limit((u_int32_t)options.rekey_limit);
1.22 provos 195:
1.65 markus 196: /* start key exchange */
1.64 markus 197: kex = kex_setup(myproposal);
1.111 markus 198: kex->kex[KEX_DH_GRP1_SHA1] = kexdh_client;
1.138 djm 199: kex->kex[KEX_DH_GRP14_SHA1] = kexdh_client;
1.111 markus 200: kex->kex[KEX_DH_GEX_SHA1] = kexgex_client;
1.147 djm 201: kex->kex[KEX_DH_GEX_SHA256] = kexgex_client;
1.184 djm 202: kex->kex[KEX_ECDH_SHA2] = kexecdh_client;
1.61 markus 203: kex->client_version_string=client_version_string;
204: kex->server_version_string=server_version_string;
1.75 markus 205: kex->verify_host_key=&verify_host_key_callback;
1.63 markus 206:
207: xxx_kex = kex;
1.22 provos 208:
1.66 markus 209: dispatch_run(DISPATCH_BLOCK, &kex->done, kex);
1.173 andreas 210:
211: if (options.use_roaming && !kex->roaming) {
212: debug("Roaming not allowed by server");
213: options.use_roaming = 0;
214: }
1.62 markus 215:
216: session_id2 = kex->session_id;
217: session_id2_len = kex->session_id_len;
1.22 provos 218:
219: #ifdef DEBUG_KEXDH
220: /* send 1st encrypted/maced/compressed message */
221: packet_start(SSH2_MSG_IGNORE);
222: packet_put_cstring("markus");
223: packet_send();
224: packet_write_wait();
225: #endif
1.1 markus 226: }
1.11 markus 227:
1.1 markus 228: /*
229: * Authenticate user
230: */
1.20 markus 231:
232: typedef struct Authctxt Authctxt;
233: typedef struct Authmethod Authmethod;
1.117 markus 234: typedef struct identity Identity;
235: typedef struct idlist Idlist;
1.20 markus 236:
1.117 markus 237: struct identity {
238: TAILQ_ENTRY(identity) next;
239: AuthenticationConnection *ac; /* set if agent supports key */
240: Key *key; /* public/private key */
241: char *filename; /* comment for agent-only keys */
242: int tried;
243: int isprivate; /* key points to the private key */
244: };
245: TAILQ_HEAD(idlist, identity);
1.20 markus 246:
247: struct Authctxt {
248: const char *server_user;
1.68 markus 249: const char *local_user;
1.20 markus 250: const char *host;
251: const char *service;
1.23 markus 252: Authmethod *method;
1.183 djm 253: sig_atomic_t success;
1.51 markus 254: char *authlist;
1.68 markus 255: /* pubkey */
1.117 markus 256: Idlist keys;
1.68 markus 257: AuthenticationConnection *agent;
258: /* hostbased */
1.100 markus 259: Sensitive *sensitive;
1.82 markus 260: /* kbd-interactive */
261: int info_req_seen;
1.121 markus 262: /* generic */
263: void *methoddata;
1.20 markus 264: };
265: struct Authmethod {
266: char *name; /* string to compare against server's list */
267: int (*userauth)(Authctxt *authctxt);
1.170 djm 268: void (*cleanup)(Authctxt *authctxt);
1.20 markus 269: int *enabled; /* flag in option struct that enables method */
270: int *batch_flag; /* flag in option struct that disables method */
271: };
272:
1.92 markus 273: void input_userauth_success(int, u_int32_t, void *);
1.172 djm 274: void input_userauth_success_unexpected(int, u_int32_t, void *);
1.92 markus 275: void input_userauth_failure(int, u_int32_t, void *);
276: void input_userauth_banner(int, u_int32_t, void *);
277: void input_userauth_error(int, u_int32_t, void *);
278: void input_userauth_info_req(int, u_int32_t, void *);
279: void input_userauth_pk_ok(int, u_int32_t, void *);
1.99 markus 280: void input_userauth_passwd_changereq(int, u_int32_t, void *);
1.170 djm 281: void input_userauth_jpake_server_step1(int, u_int32_t, void *);
282: void input_userauth_jpake_server_step2(int, u_int32_t, void *);
283: void input_userauth_jpake_server_confirm(int, u_int32_t, void *);
1.86 itojun 284:
285: int userauth_none(Authctxt *);
286: int userauth_pubkey(Authctxt *);
287: int userauth_passwd(Authctxt *);
288: int userauth_kbdint(Authctxt *);
289: int userauth_hostbased(Authctxt *);
1.170 djm 290: int userauth_jpake(Authctxt *);
291:
292: void userauth_jpake_cleanup(Authctxt *);
1.20 markus 293:
1.121 markus 294: #ifdef GSSAPI
295: int userauth_gssapi(Authctxt *authctxt);
296: void input_gssapi_response(int type, u_int32_t, void *);
297: void input_gssapi_token(int type, u_int32_t, void *);
298: void input_gssapi_hash(int type, u_int32_t, void *);
299: void input_gssapi_error(int, u_int32_t, void *);
300: void input_gssapi_errtok(int, u_int32_t, void *);
301: #endif
302:
1.86 itojun 303: void userauth(Authctxt *, char *);
1.51 markus 304:
1.117 markus 305: static int sign_and_send_pubkey(Authctxt *, Identity *);
306: static void pubkey_prepare(Authctxt *);
307: static void pubkey_cleanup(Authctxt *);
308: static Key *load_identity_file(char *);
1.76 itojun 309:
310: static Authmethod *authmethod_get(char *authlist);
311: static Authmethod *authmethod_lookup(const char *name);
312: static char *authmethods_get(void);
1.20 markus 313:
314: Authmethod authmethods[] = {
1.121 markus 315: #ifdef GSSAPI
1.132 markus 316: {"gssapi-with-mic",
1.121 markus 317: userauth_gssapi,
1.170 djm 318: NULL,
1.121 markus 319: &options.gss_authentication,
320: NULL},
321: #endif
1.81 markus 322: {"hostbased",
323: userauth_hostbased,
1.170 djm 324: NULL,
1.81 markus 325: &options.hostbased_authentication,
326: NULL},
1.20 markus 327: {"publickey",
328: userauth_pubkey,
1.170 djm 329: NULL,
1.28 markus 330: &options.pubkey_authentication,
1.20 markus 331: NULL},
1.170 djm 332: #ifdef JPAKE
333: {"jpake-01@openssh.com",
334: userauth_jpake,
335: userauth_jpake_cleanup,
336: &options.zero_knowledge_password_authentication,
337: &options.batch_mode},
338: #endif
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);
1.20 markus 378: xfree(reply);
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;
1.82 markus 400: authctxt.info_req_seen = 0;
1.23 markus 401: if (authctxt.method == NULL)
402: fatal("ssh_userauth2: internal error: cannot send userauth none request");
1.20 markus 403:
404: /* initial userauth request */
1.23 markus 405: userauth_none(&authctxt);
1.20 markus 406:
1.65 markus 407: dispatch_init(&input_userauth_error);
1.20 markus 408: dispatch_set(SSH2_MSG_USERAUTH_SUCCESS, &input_userauth_success);
409: dispatch_set(SSH2_MSG_USERAUTH_FAILURE, &input_userauth_failure);
1.35 markus 410: dispatch_set(SSH2_MSG_USERAUTH_BANNER, &input_userauth_banner);
1.20 markus 411: dispatch_run(DISPATCH_BLOCK, &authctxt.success, &authctxt); /* loop until success */
412:
1.117 markus 413: pubkey_cleanup(&authctxt);
1.119 markus 414: dispatch_range(SSH2_MSG_USERAUTH_MIN, SSH2_MSG_USERAUTH_MAX, NULL);
415:
1.109 markus 416: debug("Authentication succeeded (%s).", authctxt.method->name);
1.20 markus 417: }
1.119 markus 418:
1.20 markus 419: void
1.51 markus 420: userauth(Authctxt *authctxt, char *authlist)
421: {
1.170 djm 422: if (authctxt->method != NULL && authctxt->method->cleanup != NULL)
423: authctxt->method->cleanup(authctxt);
424:
1.121 markus 425: if (authctxt->methoddata) {
426: xfree(authctxt->methoddata);
427: authctxt->methoddata = NULL;
428: }
1.51 markus 429: if (authlist == NULL) {
430: authlist = authctxt->authlist;
431: } else {
432: if (authctxt->authlist)
433: xfree(authctxt->authlist);
434: authctxt->authlist = authlist;
435: }
436: for (;;) {
437: Authmethod *method = authmethod_get(authlist);
438: if (method == NULL)
439: fatal("Permission denied (%s).", authlist);
440: authctxt->method = method;
1.119 markus 441:
442: /* reset the per method handler */
443: dispatch_range(SSH2_MSG_USERAUTH_PER_METHOD_MIN,
444: SSH2_MSG_USERAUTH_PER_METHOD_MAX, NULL);
445:
446: /* and try new method */
1.51 markus 447: if (method->userauth(authctxt) != 0) {
448: debug2("we sent a %s packet, wait for reply", method->name);
449: break;
450: } else {
451: debug2("we did not send a packet, disable method");
452: method->enabled = NULL;
453: }
454: }
455: }
1.105 deraadt 456:
1.169 djm 457: /* ARGSUSED */
1.51 markus 458: void
1.92 markus 459: input_userauth_error(int type, u_int32_t seq, void *ctxt)
1.20 markus 460: {
1.35 markus 461: fatal("input_userauth_error: bad message during authentication: "
1.140 djm 462: "type %d", type);
1.35 markus 463: }
1.105 deraadt 464:
1.169 djm 465: /* ARGSUSED */
1.35 markus 466: void
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);
1.166 djm 481: xfree(msg);
482: }
483: xfree(raw);
1.35 markus 484: xfree(lang);
1.20 markus 485: }
1.105 deraadt 486:
1.169 djm 487: /* ARGSUSED */
1.20 markus 488: void
1.92 markus 489: input_userauth_success(int type, u_int32_t seq, void *ctxt)
1.20 markus 490: {
491: Authctxt *authctxt = ctxt;
1.172 djm 492:
1.20 markus 493: if (authctxt == NULL)
494: fatal("input_userauth_success: no authentication context");
1.126 deraadt 495: if (authctxt->authlist) {
1.51 markus 496: xfree(authctxt->authlist);
1.126 deraadt 497: authctxt->authlist = NULL;
498: }
1.172 djm 499: if (authctxt->method != NULL && authctxt->method->cleanup != NULL)
500: authctxt->method->cleanup(authctxt);
1.126 deraadt 501: if (authctxt->methoddata) {
1.121 markus 502: xfree(authctxt->methoddata);
1.126 deraadt 503: authctxt->methoddata = NULL;
504: }
1.20 markus 505: authctxt->success = 1; /* break out */
506: }
1.105 deraadt 507:
1.172 djm 508: void
509: input_userauth_success_unexpected(int type, u_int32_t seq, void *ctxt)
510: {
511: Authctxt *authctxt = ctxt;
512:
513: if (authctxt == NULL)
514: fatal("%s: no authentication context", __func__);
515:
516: fatal("Unexpected authentication success during %s.",
517: authctxt->method->name);
518: }
519:
1.169 djm 520: /* ARGSUSED */
1.20 markus 521: void
1.92 markus 522: input_userauth_failure(int type, u_int32_t seq, void *ctxt)
1.20 markus 523: {
524: Authctxt *authctxt = ctxt;
525: char *authlist = NULL;
526: int partial;
527:
528: if (authctxt == NULL)
529: fatal("input_userauth_failure: no authentication context");
530:
1.23 markus 531: authlist = packet_get_string(NULL);
1.20 markus 532: partial = packet_get_char();
1.90 markus 533: packet_check_eom();
1.20 markus 534:
535: if (partial != 0)
1.116 itojun 536: logit("Authenticated with partial success.");
1.109 markus 537: debug("Authentications that can continue: %s", authlist);
1.20 markus 538:
1.51 markus 539: userauth(authctxt, authlist);
540: }
1.169 djm 541:
542: /* ARGSUSED */
1.51 markus 543: void
1.92 markus 544: input_userauth_pk_ok(int type, u_int32_t seq, void *ctxt)
1.51 markus 545: {
546: Authctxt *authctxt = ctxt;
547: Key *key = NULL;
1.117 markus 548: Identity *id = NULL;
1.51 markus 549: Buffer b;
1.96 markus 550: int pktype, sent = 0;
551: u_int alen, blen;
552: char *pkalg, *fp;
553: u_char *pkblob;
1.51 markus 554:
555: if (authctxt == NULL)
556: fatal("input_userauth_pk_ok: no authentication context");
557: if (datafellows & SSH_BUG_PKOK) {
558: /* this is similar to SSH_BUG_PKAUTH */
559: debug2("input_userauth_pk_ok: SSH_BUG_PKOK");
560: pkblob = packet_get_string(&blen);
561: buffer_init(&b);
562: buffer_append(&b, pkblob, blen);
563: pkalg = buffer_get_string(&b, &alen);
564: buffer_free(&b);
565: } else {
566: pkalg = packet_get_string(&alen);
567: pkblob = packet_get_string(&blen);
568: }
1.90 markus 569: packet_check_eom();
1.51 markus 570:
1.117 markus 571: debug("Server accepts key: pkalg %s blen %u", pkalg, blen);
1.51 markus 572:
1.117 markus 573: if ((pktype = key_type_from_name(pkalg)) == KEY_UNSPEC) {
574: debug("unknown pkalg %s", pkalg);
575: goto done;
576: }
577: if ((key = key_from_blob(pkblob, blen)) == NULL) {
578: debug("no key from blob. pkalg %s", pkalg);
579: goto done;
580: }
581: if (key->type != pktype) {
582: error("input_userauth_pk_ok: type mismatch "
583: "for decoded key (received %d, expected %d)",
584: key->type, pktype);
585: goto done;
586: }
587: fp = key_fingerprint(key, SSH_FP_MD5, SSH_FP_HEX);
588: debug2("input_userauth_pk_ok: fp %s", fp);
589: xfree(fp);
590:
1.127 markus 591: /*
592: * search keys in the reverse order, because last candidate has been
593: * moved to the end of the queue. this also avoids confusion by
594: * duplicate keys
595: */
1.136 henning 596: TAILQ_FOREACH_REVERSE(id, &authctxt->keys, idlist, next) {
1.117 markus 597: if (key_equal(key, id->key)) {
598: sent = sign_and_send_pubkey(authctxt, id);
1.51 markus 599: break;
600: }
1.117 markus 601: }
602: done:
1.51 markus 603: if (key != NULL)
604: key_free(key);
605: xfree(pkalg);
606: xfree(pkblob);
607:
1.106 deraadt 608: /* try another method if we did not send a packet */
1.51 markus 609: if (sent == 0)
610: userauth(authctxt, NULL);
1.20 markus 611: }
1.121 markus 612:
613: #ifdef GSSAPI
1.133 djm 614: int
1.121 markus 615: userauth_gssapi(Authctxt *authctxt)
616: {
617: Gssctxt *gssctxt = NULL;
1.128 avsm 618: static gss_OID_set gss_supported = NULL;
1.139 djm 619: static u_int mech = 0;
1.121 markus 620: OM_uint32 min;
621: int ok = 0;
622:
623: /* Try one GSSAPI method at a time, rather than sending them all at
624: * once. */
625:
1.128 avsm 626: if (gss_supported == NULL)
627: gss_indicate_mechs(&min, &gss_supported);
1.121 markus 628:
629: /* Check to see if the mechanism is usable before we offer it */
1.128 avsm 630: while (mech < gss_supported->count && !ok) {
1.121 markus 631: /* My DER encoding requires length<128 */
1.128 avsm 632: if (gss_supported->elements[mech].length < 128 &&
1.161 djm 633: ssh_gssapi_check_mechanism(&gssctxt,
634: &gss_supported->elements[mech], authctxt->host)) {
1.121 markus 635: ok = 1; /* Mechanism works */
636: } else {
637: mech++;
638: }
639: }
640:
1.161 djm 641: if (!ok)
1.139 djm 642: return 0;
1.121 markus 643:
644: authctxt->methoddata=(void *)gssctxt;
645:
646: packet_start(SSH2_MSG_USERAUTH_REQUEST);
647: packet_put_cstring(authctxt->server_user);
648: packet_put_cstring(authctxt->service);
649: packet_put_cstring(authctxt->method->name);
650:
651: packet_put_int(1);
652:
1.129 markus 653: packet_put_int((gss_supported->elements[mech].length) + 2);
654: packet_put_char(SSH_GSS_OIDTYPE);
655: packet_put_char(gss_supported->elements[mech].length);
656: packet_put_raw(gss_supported->elements[mech].elements,
657: gss_supported->elements[mech].length);
1.121 markus 658:
659: packet_send();
660:
661: dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_RESPONSE, &input_gssapi_response);
662: dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, &input_gssapi_token);
663: dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERROR, &input_gssapi_error);
664: dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK, &input_gssapi_errtok);
665:
666: mech++; /* Move along to next candidate */
667:
668: return 1;
669: }
670:
1.130 markus 671: static OM_uint32
672: process_gssapi_token(void *ctxt, gss_buffer_t recv_tok)
673: {
674: Authctxt *authctxt = ctxt;
675: Gssctxt *gssctxt = authctxt->methoddata;
676: gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
1.142 djm 677: gss_buffer_desc mic = GSS_C_EMPTY_BUFFER;
678: gss_buffer_desc gssbuf;
1.132 markus 679: OM_uint32 status, ms, flags;
680: Buffer b;
1.133 djm 681:
1.130 markus 682: status = ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
1.132 markus 683: recv_tok, &send_tok, &flags);
1.130 markus 684:
685: if (send_tok.length > 0) {
686: if (GSS_ERROR(status))
687: packet_start(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK);
688: else
689: packet_start(SSH2_MSG_USERAUTH_GSSAPI_TOKEN);
1.133 djm 690:
1.130 markus 691: packet_put_string(send_tok.value, send_tok.length);
692: packet_send();
693: gss_release_buffer(&ms, &send_tok);
694: }
1.133 djm 695:
1.130 markus 696: if (status == GSS_S_COMPLETE) {
1.132 markus 697: /* send either complete or MIC, depending on mechanism */
698: if (!(flags & GSS_C_INTEG_FLAG)) {
699: packet_start(SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE);
700: packet_send();
701: } else {
702: ssh_gssapi_buildmic(&b, authctxt->server_user,
703: authctxt->service, "gssapi-with-mic");
704:
705: gssbuf.value = buffer_ptr(&b);
706: gssbuf.length = buffer_len(&b);
1.133 djm 707:
1.132 markus 708: status = ssh_gssapi_sign(gssctxt, &gssbuf, &mic);
1.133 djm 709:
1.132 markus 710: if (!GSS_ERROR(status)) {
711: packet_start(SSH2_MSG_USERAUTH_GSSAPI_MIC);
712: packet_put_string(mic.value, mic.length);
1.133 djm 713:
1.132 markus 714: packet_send();
715: }
1.133 djm 716:
1.132 markus 717: buffer_free(&b);
718: gss_release_buffer(&ms, &mic);
1.133 djm 719: }
1.130 markus 720: }
1.133 djm 721:
1.130 markus 722: return status;
723: }
724:
1.169 djm 725: /* ARGSUSED */
1.121 markus 726: void
727: input_gssapi_response(int type, u_int32_t plen, void *ctxt)
728: {
729: Authctxt *authctxt = ctxt;
730: Gssctxt *gssctxt;
731: int oidlen;
732: char *oidv;
733:
734: if (authctxt == NULL)
735: fatal("input_gssapi_response: no authentication context");
736: gssctxt = authctxt->methoddata;
737:
738: /* Setup our OID */
739: oidv = packet_get_string(&oidlen);
740:
1.129 markus 741: if (oidlen <= 2 ||
742: oidv[0] != SSH_GSS_OIDTYPE ||
743: oidv[1] != oidlen - 2) {
1.130 markus 744: xfree(oidv);
1.129 markus 745: debug("Badly encoded mechanism OID received");
746: userauth(authctxt, NULL);
747: return;
1.121 markus 748: }
1.129 markus 749:
750: if (!ssh_gssapi_check_oid(gssctxt, oidv + 2, oidlen - 2))
751: fatal("Server returned different OID than expected");
1.121 markus 752:
753: packet_check_eom();
754:
755: xfree(oidv);
756:
1.130 markus 757: if (GSS_ERROR(process_gssapi_token(ctxt, GSS_C_NO_BUFFER))) {
1.121 markus 758: /* Start again with next method on list */
759: debug("Trying to start again");
760: userauth(authctxt, NULL);
761: return;
762: }
763: }
764:
1.169 djm 765: /* ARGSUSED */
1.121 markus 766: void
767: input_gssapi_token(int type, u_int32_t plen, void *ctxt)
768: {
769: Authctxt *authctxt = ctxt;
770: gss_buffer_desc recv_tok;
1.130 markus 771: OM_uint32 status;
1.121 markus 772: u_int slen;
773:
774: if (authctxt == NULL)
775: fatal("input_gssapi_response: no authentication context");
776:
777: recv_tok.value = packet_get_string(&slen);
778: recv_tok.length = slen; /* safe typecast */
779:
780: packet_check_eom();
781:
1.130 markus 782: status = process_gssapi_token(ctxt, &recv_tok);
1.121 markus 783:
784: xfree(recv_tok.value);
785:
786: if (GSS_ERROR(status)) {
787: /* Start again with the next method in the list */
788: userauth(authctxt, NULL);
789: return;
790: }
791: }
792:
1.169 djm 793: /* ARGSUSED */
1.121 markus 794: void
795: input_gssapi_errtok(int type, u_int32_t plen, void *ctxt)
796: {
797: Authctxt *authctxt = ctxt;
798: Gssctxt *gssctxt;
799: gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
800: gss_buffer_desc recv_tok;
801: OM_uint32 status, ms;
1.123 deraadt 802: u_int len;
1.121 markus 803:
804: if (authctxt == NULL)
805: fatal("input_gssapi_response: no authentication context");
806: gssctxt = authctxt->methoddata;
807:
1.123 deraadt 808: recv_tok.value = packet_get_string(&len);
809: recv_tok.length = len;
1.121 markus 810:
811: packet_check_eom();
812:
813: /* Stick it into GSSAPI and see what it says */
814: status = ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
1.140 djm 815: &recv_tok, &send_tok, NULL);
1.121 markus 816:
817: xfree(recv_tok.value);
818: gss_release_buffer(&ms, &send_tok);
819:
820: /* Server will be returning a failed packet after this one */
821: }
822:
1.169 djm 823: /* ARGSUSED */
1.121 markus 824: void
825: input_gssapi_error(int type, u_int32_t plen, void *ctxt)
826: {
827: OM_uint32 maj, min;
828: char *msg;
829: char *lang;
830:
831: maj=packet_get_int();
832: min=packet_get_int();
833: msg=packet_get_string(NULL);
834: lang=packet_get_string(NULL);
835:
836: packet_check_eom();
837:
1.143 stevesk 838: debug("Server GSSAPI Error:\n%s", msg);
1.121 markus 839: xfree(msg);
840: xfree(lang);
841: }
842: #endif /* GSSAPI */
1.20 markus 843:
1.1 markus 844: int
1.23 markus 845: userauth_none(Authctxt *authctxt)
846: {
847: /* initial userauth request */
848: packet_start(SSH2_MSG_USERAUTH_REQUEST);
849: packet_put_cstring(authctxt->server_user);
850: packet_put_cstring(authctxt->service);
851: packet_put_cstring(authctxt->method->name);
852: packet_send();
853: return 1;
854: }
855:
856: int
1.20 markus 857: userauth_passwd(Authctxt *authctxt)
1.1 markus 858: {
1.6 markus 859: static int attempt = 0;
1.99 markus 860: char prompt[150];
1.1 markus 861: char *password;
1.175 dtucker 862: const char *host = options.host_key_alias ? options.host_key_alias :
863: authctxt->host;
1.6 markus 864:
1.13 todd 865: if (attempt++ >= options.number_of_password_prompts)
1.6 markus 866: return 0;
1.13 todd 867:
1.87 deraadt 868: if (attempt != 1)
1.13 todd 869: error("Permission denied, please try again.");
1.1 markus 870:
1.43 itojun 871: snprintf(prompt, sizeof(prompt), "%.30s@%.128s's password: ",
1.175 dtucker 872: authctxt->server_user, host);
1.1 markus 873: password = read_passphrase(prompt, 0);
874: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1.20 markus 875: packet_put_cstring(authctxt->server_user);
876: packet_put_cstring(authctxt->service);
1.23 markus 877: packet_put_cstring(authctxt->method->name);
1.1 markus 878: packet_put_char(0);
1.49 markus 879: packet_put_cstring(password);
1.1 markus 880: memset(password, 0, strlen(password));
881: xfree(password);
1.85 markus 882: packet_add_padding(64);
1.1 markus 883: packet_send();
1.99 markus 884:
1.104 deraadt 885: dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
1.99 markus 886: &input_userauth_passwd_changereq);
887:
1.1 markus 888: return 1;
889: }
1.169 djm 890:
1.99 markus 891: /*
892: * parse PASSWD_CHANGEREQ, prompt user and send SSH2_MSG_USERAUTH_REQUEST
893: */
1.169 djm 894: /* ARGSUSED */
1.99 markus 895: void
1.153 djm 896: input_userauth_passwd_changereq(int type, u_int32_t seqnr, void *ctxt)
1.99 markus 897: {
898: Authctxt *authctxt = ctxt;
899: char *info, *lang, *password = NULL, *retype = NULL;
900: char prompt[150];
1.175 dtucker 901: const char *host = options.host_key_alias ? options.host_key_alias :
902: authctxt->host;
1.99 markus 903:
904: debug2("input_userauth_passwd_changereq");
905:
906: if (authctxt == NULL)
907: fatal("input_userauth_passwd_changereq: "
908: "no authentication context");
909:
910: info = packet_get_string(NULL);
911: lang = packet_get_string(NULL);
912: if (strlen(info) > 0)
1.116 itojun 913: logit("%s", info);
1.99 markus 914: xfree(info);
915: xfree(lang);
916: packet_start(SSH2_MSG_USERAUTH_REQUEST);
917: packet_put_cstring(authctxt->server_user);
918: packet_put_cstring(authctxt->service);
919: packet_put_cstring(authctxt->method->name);
920: packet_put_char(1); /* additional info */
1.104 deraadt 921: snprintf(prompt, sizeof(prompt),
1.99 markus 922: "Enter %.30s@%.128s's old password: ",
1.175 dtucker 923: authctxt->server_user, host);
1.99 markus 924: password = read_passphrase(prompt, 0);
925: packet_put_cstring(password);
926: memset(password, 0, strlen(password));
927: xfree(password);
928: password = NULL;
929: while (password == NULL) {
1.104 deraadt 930: snprintf(prompt, sizeof(prompt),
1.99 markus 931: "Enter %.30s@%.128s's new password: ",
1.175 dtucker 932: authctxt->server_user, host);
1.99 markus 933: password = read_passphrase(prompt, RP_ALLOW_EOF);
934: if (password == NULL) {
935: /* bail out */
936: return;
937: }
1.104 deraadt 938: snprintf(prompt, sizeof(prompt),
1.99 markus 939: "Retype %.30s@%.128s's new password: ",
1.175 dtucker 940: authctxt->server_user, host);
1.99 markus 941: retype = read_passphrase(prompt, 0);
942: if (strcmp(password, retype) != 0) {
943: memset(password, 0, strlen(password));
944: xfree(password);
1.116 itojun 945: logit("Mismatch; try again, EOF to quit.");
1.99 markus 946: password = NULL;
947: }
948: memset(retype, 0, strlen(retype));
949: xfree(retype);
950: }
951: packet_put_cstring(password);
952: memset(password, 0, strlen(password));
953: xfree(password);
954: packet_add_padding(64);
955: packet_send();
1.104 deraadt 956:
957: dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
1.99 markus 958: &input_userauth_passwd_changereq);
1.117 markus 959: }
960:
1.170 djm 961: #ifdef JPAKE
962: static char *
963: pw_encrypt(const char *password, const char *crypt_scheme, const char *salt)
964: {
965: /* OpenBSD crypt(3) handles all of these */
966: if (strcmp(crypt_scheme, "crypt") == 0 ||
967: strcmp(crypt_scheme, "bcrypt") == 0 ||
968: strcmp(crypt_scheme, "md5crypt") == 0 ||
969: strcmp(crypt_scheme, "crypt-extended") == 0)
970: return xstrdup(crypt(password, salt));
971: error("%s: unsupported password encryption scheme \"%.100s\"",
972: __func__, crypt_scheme);
973: return NULL;
974: }
975:
976: static BIGNUM *
977: jpake_password_to_secret(Authctxt *authctxt, const char *crypt_scheme,
978: const char *salt)
979: {
980: char prompt[256], *password, *crypted;
981: u_char *secret;
982: u_int secret_len;
983: BIGNUM *ret;
984:
985: snprintf(prompt, sizeof(prompt), "%.30s@%.128s's password (JPAKE): ",
986: authctxt->server_user, authctxt->host);
987: password = read_passphrase(prompt, 0);
988:
989: if ((crypted = pw_encrypt(password, crypt_scheme, salt)) == NULL) {
990: logit("Disabling %s authentication", authctxt->method->name);
991: authctxt->method->enabled = NULL;
992: /* Continue with an empty password to fail gracefully */
993: crypted = xstrdup("");
994: }
995:
996: #ifdef JPAKE_DEBUG
997: debug3("%s: salt = %s", __func__, salt);
998: debug3("%s: scheme = %s", __func__, crypt_scheme);
999: debug3("%s: crypted = %s", __func__, crypted);
1000: #endif
1001:
1002: if (hash_buffer(crypted, strlen(crypted), EVP_sha256(),
1003: &secret, &secret_len) != 0)
1004: fatal("%s: hash_buffer", __func__);
1005:
1006: bzero(password, strlen(password));
1007: bzero(crypted, strlen(crypted));
1008: xfree(password);
1009: xfree(crypted);
1010:
1011: if ((ret = BN_bin2bn(secret, secret_len, NULL)) == NULL)
1012: fatal("%s: BN_bin2bn (secret)", __func__);
1013: bzero(secret, secret_len);
1014: xfree(secret);
1015:
1016: return ret;
1017: }
1018:
1019: /* ARGSUSED */
1020: void
1021: input_userauth_jpake_server_step1(int type, u_int32_t seq, void *ctxt)
1022: {
1023: Authctxt *authctxt = ctxt;
1024: struct jpake_ctx *pctx = authctxt->methoddata;
1025: u_char *x3_proof, *x4_proof, *x2_s_proof;
1026: u_int x3_proof_len, x4_proof_len, x2_s_proof_len;
1027: char *crypt_scheme, *salt;
1028:
1029: /* Disable this message */
1030: dispatch_set(SSH2_MSG_USERAUTH_JPAKE_SERVER_STEP1, NULL);
1031:
1032: if ((pctx->g_x3 = BN_new()) == NULL ||
1033: (pctx->g_x4 = BN_new()) == NULL)
1034: fatal("%s: BN_new", __func__);
1035:
1036: /* Fetch step 1 values */
1037: crypt_scheme = packet_get_string(NULL);
1038: salt = packet_get_string(NULL);
1039: pctx->server_id = packet_get_string(&pctx->server_id_len);
1040: packet_get_bignum2(pctx->g_x3);
1041: packet_get_bignum2(pctx->g_x4);
1042: x3_proof = packet_get_string(&x3_proof_len);
1043: x4_proof = packet_get_string(&x4_proof_len);
1044: packet_check_eom();
1045:
1046: JPAKE_DEBUG_CTX((pctx, "step 1 received in %s", __func__));
1047:
1048: /* Obtain password and derive secret */
1049: pctx->s = jpake_password_to_secret(authctxt, crypt_scheme, salt);
1050: bzero(crypt_scheme, strlen(crypt_scheme));
1051: bzero(salt, strlen(salt));
1052: xfree(crypt_scheme);
1053: xfree(salt);
1054: JPAKE_DEBUG_BN((pctx->s, "%s: s = ", __func__));
1055:
1056: /* Calculate step 2 values */
1057: jpake_step2(pctx->grp, pctx->s, pctx->g_x1,
1058: pctx->g_x3, pctx->g_x4, pctx->x2,
1059: pctx->server_id, pctx->server_id_len,
1060: pctx->client_id, pctx->client_id_len,
1061: x3_proof, x3_proof_len,
1062: x4_proof, x4_proof_len,
1063: &pctx->a,
1064: &x2_s_proof, &x2_s_proof_len);
1065:
1066: bzero(x3_proof, x3_proof_len);
1067: bzero(x4_proof, x4_proof_len);
1068: xfree(x3_proof);
1069: xfree(x4_proof);
1070:
1071: JPAKE_DEBUG_CTX((pctx, "step 2 sending in %s", __func__));
1072:
1073: /* Send values for step 2 */
1074: packet_start(SSH2_MSG_USERAUTH_JPAKE_CLIENT_STEP2);
1075: packet_put_bignum2(pctx->a);
1076: packet_put_string(x2_s_proof, x2_s_proof_len);
1077: packet_send();
1078:
1079: bzero(x2_s_proof, x2_s_proof_len);
1080: xfree(x2_s_proof);
1081:
1082: /* Expect step 2 packet from peer */
1083: dispatch_set(SSH2_MSG_USERAUTH_JPAKE_SERVER_STEP2,
1084: input_userauth_jpake_server_step2);
1085: }
1086:
1087: /* ARGSUSED */
1088: void
1089: input_userauth_jpake_server_step2(int type, u_int32_t seq, void *ctxt)
1090: {
1091: Authctxt *authctxt = ctxt;
1092: struct jpake_ctx *pctx = authctxt->methoddata;
1093: u_char *x4_s_proof;
1094: u_int x4_s_proof_len;
1095:
1096: /* Disable this message */
1097: dispatch_set(SSH2_MSG_USERAUTH_JPAKE_SERVER_STEP2, NULL);
1098:
1099: if ((pctx->b = BN_new()) == NULL)
1100: fatal("%s: BN_new", __func__);
1101:
1102: /* Fetch step 2 values */
1103: packet_get_bignum2(pctx->b);
1104: x4_s_proof = packet_get_string(&x4_s_proof_len);
1105: packet_check_eom();
1106:
1107: JPAKE_DEBUG_CTX((pctx, "step 2 received in %s", __func__));
1108:
1109: /* Derive shared key and calculate confirmation hash */
1110: jpake_key_confirm(pctx->grp, pctx->s, pctx->b,
1111: pctx->x2, pctx->g_x1, pctx->g_x2, pctx->g_x3, pctx->g_x4,
1112: pctx->client_id, pctx->client_id_len,
1113: pctx->server_id, pctx->server_id_len,
1114: session_id2, session_id2_len,
1115: x4_s_proof, x4_s_proof_len,
1116: &pctx->k,
1117: &pctx->h_k_cid_sessid, &pctx->h_k_cid_sessid_len);
1118:
1119: bzero(x4_s_proof, x4_s_proof_len);
1120: xfree(x4_s_proof);
1121:
1122: JPAKE_DEBUG_CTX((pctx, "confirm sending in %s", __func__));
1123:
1124: /* Send key confirmation proof */
1125: packet_start(SSH2_MSG_USERAUTH_JPAKE_CLIENT_CONFIRM);
1126: packet_put_string(pctx->h_k_cid_sessid, pctx->h_k_cid_sessid_len);
1127: packet_send();
1128:
1129: /* Expect confirmation from peer */
1130: dispatch_set(SSH2_MSG_USERAUTH_JPAKE_SERVER_CONFIRM,
1131: input_userauth_jpake_server_confirm);
1132: }
1133:
1134: /* ARGSUSED */
1135: void
1136: input_userauth_jpake_server_confirm(int type, u_int32_t seq, void *ctxt)
1137: {
1138: Authctxt *authctxt = ctxt;
1139: struct jpake_ctx *pctx = authctxt->methoddata;
1140:
1141: /* Disable this message */
1142: dispatch_set(SSH2_MSG_USERAUTH_JPAKE_SERVER_CONFIRM, NULL);
1143:
1144: pctx->h_k_sid_sessid = packet_get_string(&pctx->h_k_sid_sessid_len);
1145: packet_check_eom();
1146:
1147: JPAKE_DEBUG_CTX((pctx, "confirm received in %s", __func__));
1148:
1149: /* Verify expected confirmation hash */
1150: if (jpake_check_confirm(pctx->k,
1151: pctx->server_id, pctx->server_id_len,
1152: session_id2, session_id2_len,
1153: pctx->h_k_sid_sessid, pctx->h_k_sid_sessid_len) == 1)
1154: debug("%s: %s success", __func__, authctxt->method->name);
1155: else {
1156: debug("%s: confirmation mismatch", __func__);
1157: /* XXX stash this so if auth succeeds then we can warn/kill */
1158: }
1159:
1160: userauth_jpake_cleanup(authctxt);
1161: }
1162: #endif /* JPAKE */
1163:
1.117 markus 1164: static int
1165: identity_sign(Identity *id, u_char **sigp, u_int *lenp,
1166: u_char *data, u_int datalen)
1167: {
1168: Key *prv;
1169: int ret;
1.99 markus 1170:
1.117 markus 1171: /* the agent supports this key */
1172: if (id->ac)
1173: return (ssh_agent_sign(id->ac, id->key, sigp, lenp,
1174: data, datalen));
1175: /*
1176: * we have already loaded the private key or
1177: * the private key is stored in external hardware
1178: */
1179: if (id->isprivate || (id->key->flags & KEY_FLAG_EXT))
1180: return (key_sign(id->key, sigp, lenp, data, datalen));
1181: /* load the private key from the file */
1182: if ((prv = load_identity_file(id->filename)) == NULL)
1183: return (-1);
1184: ret = key_sign(prv, sigp, lenp, data, datalen);
1185: key_free(prv);
1186: return (ret);
1.51 markus 1187: }
1188:
1.76 itojun 1189: static int
1.117 markus 1190: sign_and_send_pubkey(Authctxt *authctxt, Identity *id)
1.1 markus 1191: {
1192: Buffer b;
1.32 markus 1193: u_char *blob, *signature;
1.96 markus 1194: u_int bloblen, slen;
1.120 markus 1195: u_int skip = 0;
1.17 markus 1196: int ret = -1;
1.23 markus 1197: int have_sig = 1;
1.182 djm 1198: char *fp;
1.1 markus 1199:
1.182 djm 1200: fp = key_fingerprint(id->key, SSH_FP_MD5, SSH_FP_HEX);
1201: debug3("sign_and_send_pubkey: %s %s", key_type(id->key), fp);
1202: xfree(fp);
1.51 markus 1203:
1.117 markus 1204: if (key_to_blob(id->key, &blob, &bloblen) == 0) {
1.28 markus 1205: /* we cannot handle this key */
1.30 markus 1206: debug3("sign_and_send_pubkey: cannot handle key");
1.28 markus 1207: return 0;
1208: }
1.1 markus 1209: /* data to be signed */
1210: buffer_init(&b);
1.26 markus 1211: if (datafellows & SSH_OLD_SESSIONID) {
1212: buffer_append(&b, session_id2, session_id2_len);
1.41 stevesk 1213: skip = session_id2_len;
1.26 markus 1214: } else {
1.14 markus 1215: buffer_put_string(&b, session_id2, session_id2_len);
1216: skip = buffer_len(&b);
1217: }
1.1 markus 1218: buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
1.20 markus 1219: buffer_put_cstring(&b, authctxt->server_user);
1.10 markus 1220: buffer_put_cstring(&b,
1.30 markus 1221: datafellows & SSH_BUG_PKSERVICE ?
1.10 markus 1222: "ssh-userauth" :
1.20 markus 1223: authctxt->service);
1.30 markus 1224: if (datafellows & SSH_BUG_PKAUTH) {
1225: buffer_put_char(&b, have_sig);
1226: } else {
1227: buffer_put_cstring(&b, authctxt->method->name);
1228: buffer_put_char(&b, have_sig);
1.117 markus 1229: buffer_put_cstring(&b, key_ssh_name(id->key));
1.30 markus 1230: }
1.1 markus 1231: buffer_put_string(&b, blob, bloblen);
1232:
1233: /* generate signature */
1.117 markus 1234: ret = identity_sign(id, &signature, &slen,
1.51 markus 1235: buffer_ptr(&b), buffer_len(&b));
1.17 markus 1236: if (ret == -1) {
1237: xfree(blob);
1238: buffer_free(&b);
1239: return 0;
1240: }
1.28 markus 1241: #ifdef DEBUG_PK
1.1 markus 1242: buffer_dump(&b);
1243: #endif
1.30 markus 1244: if (datafellows & SSH_BUG_PKSERVICE) {
1.10 markus 1245: buffer_clear(&b);
1246: buffer_append(&b, session_id2, session_id2_len);
1.51 markus 1247: skip = session_id2_len;
1.10 markus 1248: buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
1.20 markus 1249: buffer_put_cstring(&b, authctxt->server_user);
1250: buffer_put_cstring(&b, authctxt->service);
1.23 markus 1251: buffer_put_cstring(&b, authctxt->method->name);
1252: buffer_put_char(&b, have_sig);
1.30 markus 1253: if (!(datafellows & SSH_BUG_PKAUTH))
1.117 markus 1254: buffer_put_cstring(&b, key_ssh_name(id->key));
1.10 markus 1255: buffer_put_string(&b, blob, bloblen);
1256: }
1257: xfree(blob);
1.51 markus 1258:
1.1 markus 1259: /* append signature */
1260: buffer_put_string(&b, signature, slen);
1261: xfree(signature);
1262:
1263: /* skip session id and packet type */
1.14 markus 1264: if (buffer_len(&b) < skip + 1)
1.20 markus 1265: fatal("userauth_pubkey: internal error");
1.14 markus 1266: buffer_consume(&b, skip + 1);
1.1 markus 1267:
1268: /* put remaining data from buffer into packet */
1269: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1270: packet_put_raw(buffer_ptr(&b), buffer_len(&b));
1271: buffer_free(&b);
1272: packet_send();
1.17 markus 1273:
1274: return 1;
1.16 markus 1275: }
1276:
1.76 itojun 1277: static int
1.117 markus 1278: send_pubkey_test(Authctxt *authctxt, Identity *id)
1.20 markus 1279: {
1.51 markus 1280: u_char *blob;
1.97 markus 1281: u_int bloblen, have_sig = 0;
1.20 markus 1282:
1.51 markus 1283: debug3("send_pubkey_test");
1.16 markus 1284:
1.117 markus 1285: if (key_to_blob(id->key, &blob, &bloblen) == 0) {
1.51 markus 1286: /* we cannot handle this key */
1287: debug3("send_pubkey_test: cannot handle key");
1.16 markus 1288: return 0;
1289: }
1.51 markus 1290: /* register callback for USERAUTH_PK_OK message */
1291: dispatch_set(SSH2_MSG_USERAUTH_PK_OK, &input_userauth_pk_ok);
1292:
1293: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1294: packet_put_cstring(authctxt->server_user);
1295: packet_put_cstring(authctxt->service);
1296: packet_put_cstring(authctxt->method->name);
1297: packet_put_char(have_sig);
1298: if (!(datafellows & SSH_BUG_PKAUTH))
1.117 markus 1299: packet_put_cstring(key_ssh_name(id->key));
1.51 markus 1300: packet_put_string(blob, bloblen);
1301: xfree(blob);
1302: packet_send();
1303: return 1;
1304: }
1305:
1.76 itojun 1306: static Key *
1.51 markus 1307: load_identity_file(char *filename)
1308: {
1309: Key *private;
1310: char prompt[300], *passphrase;
1.178 dtucker 1311: int perm_ok = 0, quit, i;
1.52 markus 1312: struct stat st;
1.16 markus 1313:
1.52 markus 1314: if (stat(filename, &st) < 0) {
1315: debug3("no such identity: %s", filename);
1316: return NULL;
1317: }
1.152 dtucker 1318: private = key_load_private_type(KEY_UNSPEC, filename, "", NULL, &perm_ok);
1319: if (!perm_ok)
1320: return NULL;
1.56 markus 1321: if (private == NULL) {
1322: if (options.batch_mode)
1.51 markus 1323: return NULL;
1.16 markus 1324: snprintf(prompt, sizeof prompt,
1.88 deraadt 1325: "Enter passphrase for key '%.100s': ", filename);
1.20 markus 1326: for (i = 0; i < options.number_of_password_prompts; i++) {
1327: passphrase = read_passphrase(prompt, 0);
1328: if (strcmp(passphrase, "") != 0) {
1.152 dtucker 1329: private = key_load_private_type(KEY_UNSPEC,
1330: filename, passphrase, NULL, NULL);
1.51 markus 1331: quit = 0;
1.20 markus 1332: } else {
1333: debug2("no passphrase given, try next key");
1.51 markus 1334: quit = 1;
1.20 markus 1335: }
1336: memset(passphrase, 0, strlen(passphrase));
1337: xfree(passphrase);
1.56 markus 1338: if (private != NULL || quit)
1.20 markus 1339: break;
1340: debug2("bad passphrase given, try again...");
1.16 markus 1341: }
1342: }
1.51 markus 1343: return private;
1344: }
1345:
1.117 markus 1346: /*
1347: * try keys in the following order:
1348: * 1. agent keys that are found in the config file
1349: * 2. other agent keys
1350: * 3. keys that are only listed in the config file
1351: */
1352: static void
1353: pubkey_prepare(Authctxt *authctxt)
1.51 markus 1354: {
1.117 markus 1355: Identity *id;
1356: Idlist agent, files, *preferred;
1357: Key *key;
1358: AuthenticationConnection *ac;
1359: char *comment;
1360: int i, found;
1.51 markus 1361:
1.117 markus 1362: TAILQ_INIT(&agent); /* keys from the agent */
1363: TAILQ_INIT(&files); /* keys from the config file */
1364: preferred = &authctxt->keys;
1365: TAILQ_INIT(preferred); /* preferred order of keys */
1366:
1367: /* list of keys stored in the filesystem */
1368: for (i = 0; i < options.num_identity_files; i++) {
1369: key = options.identity_keys[i];
1370: if (key && key->type == KEY_RSA1)
1.180 djm 1371: continue;
1372: if (key && key->cert && key->cert->type != SSH2_CERT_TYPE_USER)
1.117 markus 1373: continue;
1374: options.identity_keys[i] = NULL;
1.150 djm 1375: id = xcalloc(1, sizeof(*id));
1.117 markus 1376: id->key = key;
1377: id->filename = xstrdup(options.identity_files[i]);
1378: TAILQ_INSERT_TAIL(&files, id, next);
1379: }
1380: /* list of keys supported by the agent */
1381: if ((ac = ssh_get_authentication_connection())) {
1382: for (key = ssh_get_first_identity(ac, &comment, 2);
1383: key != NULL;
1384: key = ssh_get_next_identity(ac, &comment, 2)) {
1385: found = 0;
1386: TAILQ_FOREACH(id, &files, next) {
1.133 djm 1387: /* agent keys from the config file are preferred */
1.117 markus 1388: if (key_equal(key, id->key)) {
1389: key_free(key);
1390: xfree(comment);
1391: TAILQ_REMOVE(&files, id, next);
1392: TAILQ_INSERT_TAIL(preferred, id, next);
1393: id->ac = ac;
1394: found = 1;
1395: break;
1396: }
1397: }
1.135 markus 1398: if (!found && !options.identities_only) {
1.150 djm 1399: id = xcalloc(1, sizeof(*id));
1.117 markus 1400: id->key = key;
1401: id->filename = comment;
1402: id->ac = ac;
1403: TAILQ_INSERT_TAIL(&agent, id, next);
1404: }
1405: }
1406: /* append remaining agent keys */
1407: for (id = TAILQ_FIRST(&agent); id; id = TAILQ_FIRST(&agent)) {
1408: TAILQ_REMOVE(&agent, id, next);
1409: TAILQ_INSERT_TAIL(preferred, id, next);
1410: }
1411: authctxt->agent = ac;
1412: }
1413: /* append remaining keys from the config file */
1414: for (id = TAILQ_FIRST(&files); id; id = TAILQ_FIRST(&files)) {
1415: TAILQ_REMOVE(&files, id, next);
1416: TAILQ_INSERT_TAIL(preferred, id, next);
1417: }
1418: TAILQ_FOREACH(id, preferred, next) {
1419: debug2("key: %s (%p)", id->filename, id->key);
1420: }
1.17 markus 1421: }
1422:
1.117 markus 1423: static void
1424: pubkey_cleanup(Authctxt *authctxt)
1.51 markus 1425: {
1.117 markus 1426: Identity *id;
1.51 markus 1427:
1.117 markus 1428: if (authctxt->agent != NULL)
1429: ssh_close_authentication_connection(authctxt->agent);
1430: for (id = TAILQ_FIRST(&authctxt->keys); id;
1431: id = TAILQ_FIRST(&authctxt->keys)) {
1432: TAILQ_REMOVE(&authctxt->keys, id, next);
1433: if (id->key)
1434: key_free(id->key);
1435: if (id->filename)
1436: xfree(id->filename);
1437: xfree(id);
1438: }
1.1 markus 1439: }
1440:
1.20 markus 1441: int
1442: userauth_pubkey(Authctxt *authctxt)
1443: {
1.117 markus 1444: Identity *id;
1.20 markus 1445: int sent = 0;
1446:
1.117 markus 1447: while ((id = TAILQ_FIRST(&authctxt->keys))) {
1448: if (id->tried++)
1449: return (0);
1.127 markus 1450: /* move key to the end of the queue */
1.117 markus 1451: TAILQ_REMOVE(&authctxt->keys, id, next);
1452: TAILQ_INSERT_TAIL(&authctxt->keys, id, next);
1453: /*
1454: * send a test message if we have the public key. for
1455: * encrypted keys we cannot do this and have to load the
1456: * private key instead
1457: */
1458: if (id->key && id->key->type != KEY_RSA1) {
1.181 djm 1459: debug("Offering %s public key: %s", key_type(id->key),
1460: id->filename);
1.117 markus 1461: sent = send_pubkey_test(authctxt, id);
1462: } else if (id->key == NULL) {
1463: debug("Trying private key: %s", id->filename);
1464: id->key = load_identity_file(id->filename);
1465: if (id->key != NULL) {
1466: id->isprivate = 1;
1467: sent = sign_and_send_pubkey(authctxt, id);
1468: key_free(id->key);
1469: id->key = NULL;
1.51 markus 1470: }
1471: }
1.117 markus 1472: if (sent)
1473: return (sent);
1.28 markus 1474: }
1.117 markus 1475: return (0);
1.20 markus 1476: }
1477:
1.23 markus 1478: /*
1479: * Send userauth request message specifying keyboard-interactive method.
1480: */
1481: int
1482: userauth_kbdint(Authctxt *authctxt)
1483: {
1484: static int attempt = 0;
1485:
1486: if (attempt++ >= options.number_of_password_prompts)
1487: return 0;
1.82 markus 1488: /* disable if no SSH2_MSG_USERAUTH_INFO_REQUEST has been seen */
1489: if (attempt > 1 && !authctxt->info_req_seen) {
1490: debug3("userauth_kbdint: disable: no info_req_seen");
1491: dispatch_set(SSH2_MSG_USERAUTH_INFO_REQUEST, NULL);
1492: return 0;
1493: }
1.23 markus 1494:
1495: debug2("userauth_kbdint");
1496: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1497: packet_put_cstring(authctxt->server_user);
1498: packet_put_cstring(authctxt->service);
1499: packet_put_cstring(authctxt->method->name);
1500: packet_put_cstring(""); /* lang */
1501: packet_put_cstring(options.kbd_interactive_devices ?
1502: options.kbd_interactive_devices : "");
1503: packet_send();
1504:
1505: dispatch_set(SSH2_MSG_USERAUTH_INFO_REQUEST, &input_userauth_info_req);
1506: return 1;
1507: }
1508:
1509: /*
1.46 markus 1510: * parse INFO_REQUEST, prompt user and send INFO_RESPONSE
1.23 markus 1511: */
1512: void
1.92 markus 1513: input_userauth_info_req(int type, u_int32_t seq, void *ctxt)
1.23 markus 1514: {
1515: Authctxt *authctxt = ctxt;
1.46 markus 1516: char *name, *inst, *lang, *prompt, *response;
1.32 markus 1517: u_int num_prompts, i;
1.23 markus 1518: int echo = 0;
1519:
1520: debug2("input_userauth_info_req");
1521:
1522: if (authctxt == NULL)
1523: fatal("input_userauth_info_req: no authentication context");
1.82 markus 1524:
1525: authctxt->info_req_seen = 1;
1.23 markus 1526:
1527: name = packet_get_string(NULL);
1528: inst = packet_get_string(NULL);
1529: lang = packet_get_string(NULL);
1530: if (strlen(name) > 0)
1.116 itojun 1531: logit("%s", name);
1.23 markus 1532: if (strlen(inst) > 0)
1.116 itojun 1533: logit("%s", inst);
1.46 markus 1534: xfree(name);
1.23 markus 1535: xfree(inst);
1.46 markus 1536: xfree(lang);
1.23 markus 1537:
1538: num_prompts = packet_get_int();
1539: /*
1540: * Begin to build info response packet based on prompts requested.
1541: * We commit to providing the correct number of responses, so if
1542: * further on we run into a problem that prevents this, we have to
1543: * be sure and clean this up and send a correct error response.
1544: */
1545: packet_start(SSH2_MSG_USERAUTH_INFO_RESPONSE);
1546: packet_put_int(num_prompts);
1547:
1.73 markus 1548: debug2("input_userauth_info_req: num_prompts %d", num_prompts);
1.23 markus 1549: for (i = 0; i < num_prompts; i++) {
1550: prompt = packet_get_string(NULL);
1551: echo = packet_get_char();
1552:
1.77 markus 1553: response = read_passphrase(prompt, echo ? RP_ECHO : 0);
1.23 markus 1554:
1.49 markus 1555: packet_put_cstring(response);
1.23 markus 1556: memset(response, 0, strlen(response));
1557: xfree(response);
1558: xfree(prompt);
1559: }
1.90 markus 1560: packet_check_eom(); /* done with parsing incoming message. */
1.23 markus 1561:
1.85 markus 1562: packet_add_padding(64);
1.23 markus 1563: packet_send();
1.68 markus 1564: }
1565:
1.100 markus 1566: static int
1.105 deraadt 1567: ssh_keysign(Key *key, u_char **sigp, u_int *lenp,
1.100 markus 1568: u_char *data, u_int datalen)
1569: {
1570: Buffer b;
1.101 markus 1571: struct stat st;
1.100 markus 1572: pid_t pid;
1.103 markus 1573: int to[2], from[2], status, version = 2;
1.100 markus 1574:
1.109 markus 1575: debug2("ssh_keysign called");
1.100 markus 1576:
1.101 markus 1577: if (stat(_PATH_SSH_KEY_SIGN, &st) < 0) {
1.179 dtucker 1578: error("ssh_keysign: not installed: %s", strerror(errno));
1.101 markus 1579: return -1;
1580: }
1.100 markus 1581: if (fflush(stdout) != 0)
1582: error("ssh_keysign: fflush: %s", strerror(errno));
1583: if (pipe(to) < 0) {
1584: error("ssh_keysign: pipe: %s", strerror(errno));
1585: return -1;
1586: }
1587: if (pipe(from) < 0) {
1588: error("ssh_keysign: pipe: %s", strerror(errno));
1589: return -1;
1590: }
1591: if ((pid = fork()) < 0) {
1592: error("ssh_keysign: fork: %s", strerror(errno));
1593: return -1;
1594: }
1595: if (pid == 0) {
1.174 dtucker 1596: /* keep the socket on exec */
1597: fcntl(packet_get_connection_in(), F_SETFD, 0);
1.155 markus 1598: permanently_drop_suid(getuid());
1.100 markus 1599: close(from[0]);
1600: if (dup2(from[1], STDOUT_FILENO) < 0)
1601: fatal("ssh_keysign: dup2: %s", strerror(errno));
1602: close(to[1]);
1603: if (dup2(to[0], STDIN_FILENO) < 0)
1604: fatal("ssh_keysign: dup2: %s", strerror(errno));
1.103 markus 1605: close(from[1]);
1606: close(to[0]);
1.102 markus 1607: execl(_PATH_SSH_KEY_SIGN, _PATH_SSH_KEY_SIGN, (char *) 0);
1.100 markus 1608: fatal("ssh_keysign: exec(%s): %s", _PATH_SSH_KEY_SIGN,
1609: strerror(errno));
1610: }
1611: close(from[1]);
1612: close(to[0]);
1613:
1614: buffer_init(&b);
1.103 markus 1615: buffer_put_int(&b, packet_get_connection_in()); /* send # of socket */
1.100 markus 1616: buffer_put_string(&b, data, datalen);
1.131 djm 1617: if (ssh_msg_send(to[1], version, &b) == -1)
1618: fatal("ssh_keysign: couldn't send request");
1.100 markus 1619:
1.110 djm 1620: if (ssh_msg_recv(from[0], &b) < 0) {
1.101 markus 1621: error("ssh_keysign: no reply");
1.134 markus 1622: buffer_free(&b);
1.100 markus 1623: return -1;
1624: }
1.101 markus 1625: close(from[0]);
1626: close(to[1]);
1627:
1.103 markus 1628: while (waitpid(pid, &status, 0) < 0)
1629: if (errno != EINTR)
1630: break;
1.101 markus 1631:
1.100 markus 1632: if (buffer_get_char(&b) != version) {
1.101 markus 1633: error("ssh_keysign: bad version");
1.134 markus 1634: buffer_free(&b);
1.100 markus 1635: return -1;
1636: }
1637: *sigp = buffer_get_string(&b, lenp);
1.134 markus 1638: buffer_free(&b);
1.100 markus 1639:
1640: return 0;
1641: }
1642:
1.68 markus 1643: int
1644: userauth_hostbased(Authctxt *authctxt)
1645: {
1646: Key *private = NULL;
1.100 markus 1647: Sensitive *sensitive = authctxt->sensitive;
1.68 markus 1648: Buffer b;
1649: u_char *signature, *blob;
1.179 dtucker 1650: char *chost, *pkalg, *p;
1.72 markus 1651: const char *service;
1.68 markus 1652: u_int blen, slen;
1.176 dtucker 1653: int ok, i, found = 0;
1.68 markus 1654:
1655: /* check for a useful key */
1.100 markus 1656: for (i = 0; i < sensitive->nkeys; i++) {
1657: private = sensitive->keys[i];
1.68 markus 1658: if (private && private->type != KEY_RSA1) {
1659: found = 1;
1660: /* we take and free the key */
1.100 markus 1661: sensitive->keys[i] = NULL;
1.68 markus 1662: break;
1663: }
1664: }
1665: if (!found) {
1.109 markus 1666: debug("No more client hostkeys for hostbased authentication.");
1.68 markus 1667: return 0;
1668: }
1669: if (key_to_blob(private, &blob, &blen) == 0) {
1670: key_free(private);
1671: return 0;
1672: }
1.84 markus 1673: /* figure out a name for the client host */
1.179 dtucker 1674: p = get_local_name(packet_get_connection_in());
1.84 markus 1675: if (p == NULL) {
1676: error("userauth_hostbased: cannot get local ipaddr/name");
1677: key_free(private);
1.148 djm 1678: xfree(blob);
1.84 markus 1679: return 0;
1680: }
1.150 djm 1681: xasprintf(&chost, "%s.", p);
1.84 markus 1682: debug2("userauth_hostbased: chost %s", chost);
1.112 markus 1683: xfree(p);
1.84 markus 1684:
1.72 markus 1685: service = datafellows & SSH_BUG_HBSERVICE ? "ssh-userauth" :
1686: authctxt->service;
1.68 markus 1687: pkalg = xstrdup(key_ssh_name(private));
1688: buffer_init(&b);
1689: /* construct data */
1.72 markus 1690: buffer_put_string(&b, session_id2, session_id2_len);
1.68 markus 1691: buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
1692: buffer_put_cstring(&b, authctxt->server_user);
1.72 markus 1693: buffer_put_cstring(&b, service);
1.68 markus 1694: buffer_put_cstring(&b, authctxt->method->name);
1695: buffer_put_cstring(&b, pkalg);
1696: buffer_put_string(&b, blob, blen);
1697: buffer_put_cstring(&b, chost);
1698: buffer_put_cstring(&b, authctxt->local_user);
1699: #ifdef DEBUG_PK
1700: buffer_dump(&b);
1701: #endif
1.100 markus 1702: if (sensitive->external_keysign)
1703: ok = ssh_keysign(private, &signature, &slen,
1704: buffer_ptr(&b), buffer_len(&b));
1705: else
1706: ok = key_sign(private, &signature, &slen,
1707: buffer_ptr(&b), buffer_len(&b));
1.68 markus 1708: key_free(private);
1709: buffer_free(&b);
1710: if (ok != 0) {
1711: error("key_sign failed");
1712: xfree(chost);
1713: xfree(pkalg);
1.148 djm 1714: xfree(blob);
1.68 markus 1715: return 0;
1716: }
1717: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1718: packet_put_cstring(authctxt->server_user);
1719: packet_put_cstring(authctxt->service);
1720: packet_put_cstring(authctxt->method->name);
1721: packet_put_cstring(pkalg);
1722: packet_put_string(blob, blen);
1723: packet_put_cstring(chost);
1724: packet_put_cstring(authctxt->local_user);
1725: packet_put_string(signature, slen);
1726: memset(signature, 's', slen);
1727: xfree(signature);
1728: xfree(chost);
1729: xfree(pkalg);
1.148 djm 1730: xfree(blob);
1.68 markus 1731:
1732: packet_send();
1733: return 1;
1.23 markus 1734: }
1.20 markus 1735:
1.170 djm 1736: #ifdef JPAKE
1737: int
1738: userauth_jpake(Authctxt *authctxt)
1739: {
1740: struct jpake_ctx *pctx;
1741: u_char *x1_proof, *x2_proof;
1742: u_int x1_proof_len, x2_proof_len;
1743: static int attempt = 0; /* XXX share with userauth_password's? */
1744:
1745: if (attempt++ >= options.number_of_password_prompts)
1746: return 0;
1747: if (attempt != 1)
1748: error("Permission denied, please try again.");
1749:
1750: if (authctxt->methoddata != NULL)
1751: fatal("%s: authctxt->methoddata already set (%p)",
1752: __func__, authctxt->methoddata);
1753:
1754: authctxt->methoddata = pctx = jpake_new();
1755:
1756: /*
1757: * Send request immediately, to get the protocol going while
1758: * we do the initial computations.
1759: */
1760: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1761: packet_put_cstring(authctxt->server_user);
1762: packet_put_cstring(authctxt->service);
1763: packet_put_cstring(authctxt->method->name);
1764: packet_send();
1765: packet_write_wait();
1766:
1767: jpake_step1(pctx->grp,
1768: &pctx->client_id, &pctx->client_id_len,
1769: &pctx->x1, &pctx->x2, &pctx->g_x1, &pctx->g_x2,
1770: &x1_proof, &x1_proof_len,
1771: &x2_proof, &x2_proof_len);
1772:
1773: JPAKE_DEBUG_CTX((pctx, "step 1 sending in %s", __func__));
1774:
1775: packet_start(SSH2_MSG_USERAUTH_JPAKE_CLIENT_STEP1);
1776: packet_put_string(pctx->client_id, pctx->client_id_len);
1777: packet_put_bignum2(pctx->g_x1);
1778: packet_put_bignum2(pctx->g_x2);
1779: packet_put_string(x1_proof, x1_proof_len);
1780: packet_put_string(x2_proof, x2_proof_len);
1781: packet_send();
1782:
1783: bzero(x1_proof, x1_proof_len);
1784: bzero(x2_proof, x2_proof_len);
1785: xfree(x1_proof);
1786: xfree(x2_proof);
1787:
1788: /* Expect step 1 packet from peer */
1789: dispatch_set(SSH2_MSG_USERAUTH_JPAKE_SERVER_STEP1,
1790: input_userauth_jpake_server_step1);
1.172 djm 1791: dispatch_set(SSH2_MSG_USERAUTH_SUCCESS,
1792: &input_userauth_success_unexpected);
1.170 djm 1793:
1794: return 1;
1795: }
1796:
1797: void
1798: userauth_jpake_cleanup(Authctxt *authctxt)
1799: {
1800: debug3("%s: clean up", __func__);
1801: if (authctxt->methoddata != NULL) {
1802: jpake_free(authctxt->methoddata);
1803: authctxt->methoddata = NULL;
1804: }
1.172 djm 1805: dispatch_set(SSH2_MSG_USERAUTH_SUCCESS, &input_userauth_success);
1.170 djm 1806: }
1807: #endif /* JPAKE */
1808:
1.20 markus 1809: /* find auth method */
1810:
1811: /*
1812: * given auth method name, if configurable options permit this method fill
1813: * in auth_ident field and return true, otherwise return false.
1814: */
1.76 itojun 1815: static int
1.20 markus 1816: authmethod_is_enabled(Authmethod *method)
1817: {
1818: if (method == NULL)
1819: return 0;
1820: /* return false if options indicate this method is disabled */
1821: if (method->enabled == NULL || *method->enabled == 0)
1822: return 0;
1823: /* return false if batch mode is enabled but method needs interactive mode */
1824: if (method->batch_flag != NULL && *method->batch_flag != 0)
1825: return 0;
1826: return 1;
1827: }
1828:
1.76 itojun 1829: static Authmethod *
1.20 markus 1830: authmethod_lookup(const char *name)
1.1 markus 1831: {
1.20 markus 1832: Authmethod *method = NULL;
1833: if (name != NULL)
1834: for (method = authmethods; method->name != NULL; method++)
1835: if (strcmp(name, method->name) == 0)
1836: return method;
1837: debug2("Unrecognized authentication method name: %s", name ? name : "NULL");
1838: return NULL;
1839: }
1.1 markus 1840:
1.53 markus 1841: /* XXX internal state */
1842: static Authmethod *current = NULL;
1843: static char *supported = NULL;
1844: static char *preferred = NULL;
1.105 deraadt 1845:
1.20 markus 1846: /*
1847: * Given the authentication method list sent by the server, return the
1848: * next method we should try. If the server initially sends a nil list,
1.67 markus 1849: * use a built-in default list.
1.41 stevesk 1850: */
1.76 itojun 1851: static Authmethod *
1.20 markus 1852: authmethod_get(char *authlist)
1853: {
1.53 markus 1854: char *name = NULL;
1.97 markus 1855: u_int next;
1.41 stevesk 1856:
1.20 markus 1857: /* Use a suitable default if we're passed a nil list. */
1858: if (authlist == NULL || strlen(authlist) == 0)
1.53 markus 1859: authlist = options.preferred_authentications;
1.20 markus 1860:
1.53 markus 1861: if (supported == NULL || strcmp(authlist, supported) != 0) {
1862: debug3("start over, passed a different list %s", authlist);
1863: if (supported != NULL)
1864: xfree(supported);
1865: supported = xstrdup(authlist);
1866: preferred = options.preferred_authentications;
1867: debug3("preferred %s", preferred);
1868: current = NULL;
1869: } else if (current != NULL && authmethod_is_enabled(current))
1870: return current;
1.20 markus 1871:
1.53 markus 1872: for (;;) {
1873: if ((name = match_list(preferred, supported, &next)) == NULL) {
1.109 markus 1874: debug("No more authentication methods to try.");
1.53 markus 1875: current = NULL;
1876: return NULL;
1877: }
1878: preferred += next;
1.23 markus 1879: debug3("authmethod_lookup %s", name);
1.53 markus 1880: debug3("remaining preferred: %s", preferred);
1881: if ((current = authmethod_lookup(name)) != NULL &&
1882: authmethod_is_enabled(current)) {
1.23 markus 1883: debug3("authmethod_is_enabled %s", name);
1.109 markus 1884: debug("Next authentication method: %s", name);
1.187 ! djm 1885: xfree(name);
1.53 markus 1886: return current;
1.23 markus 1887: }
1.1 markus 1888: }
1.187 ! djm 1889: if (name != NULL)
! 1890: xfree(name);
1.53 markus 1891: }
1.1 markus 1892:
1.79 stevesk 1893: static char *
1.53 markus 1894: authmethods_get(void)
1895: {
1896: Authmethod *method = NULL;
1.93 markus 1897: Buffer b;
1898: char *list;
1.27 provos 1899:
1.93 markus 1900: buffer_init(&b);
1.53 markus 1901: for (method = authmethods; method->name != NULL; method++) {
1902: if (authmethod_is_enabled(method)) {
1.93 markus 1903: if (buffer_len(&b) > 0)
1904: buffer_append(&b, ",", 1);
1905: buffer_append(&b, method->name, strlen(method->name));
1.53 markus 1906: }
1907: }
1.93 markus 1908: buffer_append(&b, "\0", 1);
1909: list = xstrdup(buffer_ptr(&b));
1910: buffer_free(&b);
1911: return list;
1.1 markus 1912: }
1.170 djm 1913:
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