Annotation of src/usr.bin/ssh/sshconnect2.c, Revision 1.197
1.197 ! djm 1: /* $OpenBSD: sshconnect2.c,v 1.196 2013/05/16 02:00:34 dtucker 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;
1.188 djm 106: u_int i;
1.186 djm 107:
108: /* Find all hostkeys for this hostname */
109: get_hostfile_hostname_ipaddr(host, hostaddr, port, &hostname, NULL);
110: hostkeys = init_hostkeys();
1.188 djm 111: for (i = 0; i < options.num_user_hostfiles; i++)
112: load_hostkeys(hostkeys, hostname, options.user_hostfiles[i]);
113: for (i = 0; i < options.num_system_hostfiles; i++)
114: load_hostkeys(hostkeys, hostname, options.system_hostfiles[i]);
1.186 djm 115:
116: oavail = avail = xstrdup(KEX_DEFAULT_PK_ALG);
117: maxlen = strlen(avail) + 1;
118: first = xmalloc(maxlen);
119: last = xmalloc(maxlen);
120: *first = *last = '\0';
121:
122: #define ALG_APPEND(to, from) \
123: do { \
124: if (*to != '\0') \
125: strlcat(to, ",", maxlen); \
126: strlcat(to, from, maxlen); \
127: } while (0)
128:
129: while ((alg = strsep(&avail, ",")) && *alg != '\0') {
130: if ((ktype = key_type_from_name(alg)) == KEY_UNSPEC)
131: fatal("%s: unknown alg %s", __func__, alg);
132: if (lookup_key_in_hostkeys_by_type(hostkeys,
133: key_type_plain(ktype), NULL))
134: ALG_APPEND(first, alg);
135: else
136: ALG_APPEND(last, alg);
137: }
138: #undef ALG_APPEND
139: xasprintf(&ret, "%s%s%s", first, *first == '\0' ? "" : ",", last);
140: if (*first != '\0')
141: debug3("%s: prefer hostkeyalgs: %s", __func__, first);
142:
1.197 ! djm 143: free(first);
! 144: free(last);
! 145: free(hostname);
! 146: free(oavail);
1.186 djm 147: free_hostkeys(hostkeys);
148:
149: return ret;
150: }
151:
1.1 markus 152: void
1.186 djm 153: ssh_kex2(char *host, struct sockaddr *hostaddr, u_short port)
1.22 provos 154: {
155: Kex *kex;
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] =
1.70 markus 185: options.hostkeyalgorithms;
1.186 djm 186: else {
187: /* Prefer algorithms that we already have keys for */
188: myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] =
189: order_hostkeyalgs(host, hostaddr, port);
190: }
1.185 djm 191: if (options.kex_algorithms != NULL)
192: myproposal[PROPOSAL_KEX_ALGS] = options.kex_algorithms;
1.115 markus 193:
1.196 dtucker 194: if (options.rekey_limit || options.rekey_interval)
195: packet_set_rekey_limits((u_int32_t)options.rekey_limit,
196: (time_t)options.rekey_interval);
1.22 provos 197:
1.65 markus 198: /* start key exchange */
1.64 markus 199: kex = kex_setup(myproposal);
1.111 markus 200: kex->kex[KEX_DH_GRP1_SHA1] = kexdh_client;
1.138 djm 201: kex->kex[KEX_DH_GRP14_SHA1] = kexdh_client;
1.111 markus 202: kex->kex[KEX_DH_GEX_SHA1] = kexgex_client;
1.147 djm 203: kex->kex[KEX_DH_GEX_SHA256] = kexgex_client;
1.184 djm 204: kex->kex[KEX_ECDH_SHA2] = kexecdh_client;
1.61 markus 205: kex->client_version_string=client_version_string;
206: kex->server_version_string=server_version_string;
1.75 markus 207: kex->verify_host_key=&verify_host_key_callback;
1.63 markus 208:
209: xxx_kex = kex;
1.22 provos 210:
1.66 markus 211: dispatch_run(DISPATCH_BLOCK, &kex->done, kex);
1.173 andreas 212:
213: if (options.use_roaming && !kex->roaming) {
214: debug("Roaming not allowed by server");
215: options.use_roaming = 0;
216: }
1.62 markus 217:
218: session_id2 = kex->session_id;
219: session_id2_len = kex->session_id_len;
1.22 provos 220:
221: #ifdef DEBUG_KEXDH
222: /* send 1st encrypted/maced/compressed message */
223: packet_start(SSH2_MSG_IGNORE);
224: packet_put_cstring("markus");
225: packet_send();
226: packet_write_wait();
227: #endif
1.1 markus 228: }
1.11 markus 229:
1.1 markus 230: /*
231: * Authenticate user
232: */
1.20 markus 233:
234: typedef struct Authctxt Authctxt;
235: typedef struct Authmethod Authmethod;
1.117 markus 236: typedef struct identity Identity;
237: typedef struct idlist Idlist;
1.20 markus 238:
1.117 markus 239: struct identity {
240: TAILQ_ENTRY(identity) next;
241: AuthenticationConnection *ac; /* set if agent supports key */
242: Key *key; /* public/private key */
243: char *filename; /* comment for agent-only keys */
244: int tried;
245: int isprivate; /* key points to the private key */
1.191 dtucker 246: int userprovided;
1.117 markus 247: };
248: TAILQ_HEAD(idlist, identity);
1.20 markus 249:
250: struct Authctxt {
251: const char *server_user;
1.68 markus 252: const char *local_user;
1.20 markus 253: const char *host;
254: const char *service;
1.23 markus 255: Authmethod *method;
1.183 djm 256: sig_atomic_t success;
1.51 markus 257: char *authlist;
1.68 markus 258: /* pubkey */
1.117 markus 259: Idlist keys;
1.68 markus 260: AuthenticationConnection *agent;
261: /* hostbased */
1.100 markus 262: Sensitive *sensitive;
1.82 markus 263: /* kbd-interactive */
264: int info_req_seen;
1.121 markus 265: /* generic */
266: void *methoddata;
1.20 markus 267: };
268: struct Authmethod {
269: char *name; /* string to compare against server's list */
270: int (*userauth)(Authctxt *authctxt);
1.170 djm 271: void (*cleanup)(Authctxt *authctxt);
1.20 markus 272: int *enabled; /* flag in option struct that enables method */
273: int *batch_flag; /* flag in option struct that disables method */
274: };
275:
1.92 markus 276: void input_userauth_success(int, u_int32_t, void *);
1.172 djm 277: void input_userauth_success_unexpected(int, u_int32_t, void *);
1.92 markus 278: void input_userauth_failure(int, u_int32_t, void *);
279: void input_userauth_banner(int, u_int32_t, void *);
280: void input_userauth_error(int, u_int32_t, void *);
281: void input_userauth_info_req(int, u_int32_t, void *);
282: void input_userauth_pk_ok(int, u_int32_t, void *);
1.99 markus 283: void input_userauth_passwd_changereq(int, u_int32_t, void *);
1.170 djm 284: void input_userauth_jpake_server_step1(int, u_int32_t, void *);
285: void input_userauth_jpake_server_step2(int, u_int32_t, void *);
286: void input_userauth_jpake_server_confirm(int, u_int32_t, void *);
1.86 itojun 287:
288: int userauth_none(Authctxt *);
289: int userauth_pubkey(Authctxt *);
290: int userauth_passwd(Authctxt *);
291: int userauth_kbdint(Authctxt *);
292: int userauth_hostbased(Authctxt *);
1.170 djm 293: int userauth_jpake(Authctxt *);
294:
295: void userauth_jpake_cleanup(Authctxt *);
1.20 markus 296:
1.121 markus 297: #ifdef GSSAPI
298: int userauth_gssapi(Authctxt *authctxt);
299: void input_gssapi_response(int type, u_int32_t, void *);
300: void input_gssapi_token(int type, u_int32_t, void *);
301: void input_gssapi_hash(int type, u_int32_t, void *);
302: void input_gssapi_error(int, u_int32_t, void *);
303: void input_gssapi_errtok(int, u_int32_t, void *);
304: #endif
305:
1.86 itojun 306: void userauth(Authctxt *, char *);
1.51 markus 307:
1.117 markus 308: static int sign_and_send_pubkey(Authctxt *, Identity *);
309: static void pubkey_prepare(Authctxt *);
310: static void pubkey_cleanup(Authctxt *);
1.191 dtucker 311: static Key *load_identity_file(char *, int);
1.76 itojun 312:
313: static Authmethod *authmethod_get(char *authlist);
314: static Authmethod *authmethod_lookup(const char *name);
315: static char *authmethods_get(void);
1.20 markus 316:
317: Authmethod authmethods[] = {
1.121 markus 318: #ifdef GSSAPI
1.132 markus 319: {"gssapi-with-mic",
1.121 markus 320: userauth_gssapi,
1.170 djm 321: NULL,
1.121 markus 322: &options.gss_authentication,
323: NULL},
324: #endif
1.81 markus 325: {"hostbased",
326: userauth_hostbased,
1.170 djm 327: NULL,
1.81 markus 328: &options.hostbased_authentication,
329: NULL},
1.20 markus 330: {"publickey",
331: userauth_pubkey,
1.170 djm 332: NULL,
1.28 markus 333: &options.pubkey_authentication,
1.20 markus 334: NULL},
1.170 djm 335: #ifdef JPAKE
336: {"jpake-01@openssh.com",
337: userauth_jpake,
338: userauth_jpake_cleanup,
339: &options.zero_knowledge_password_authentication,
340: &options.batch_mode},
341: #endif
1.81 markus 342: {"keyboard-interactive",
343: userauth_kbdint,
1.170 djm 344: NULL,
1.81 markus 345: &options.kbd_interactive_authentication,
346: &options.batch_mode},
1.20 markus 347: {"password",
348: userauth_passwd,
1.170 djm 349: NULL,
1.20 markus 350: &options.password_authentication,
1.23 markus 351: &options.batch_mode},
352: {"none",
353: userauth_none,
354: NULL,
1.170 djm 355: NULL,
1.23 markus 356: NULL},
1.170 djm 357: {NULL, NULL, NULL, NULL, NULL}
1.20 markus 358: };
359:
360: void
1.68 markus 361: ssh_userauth2(const char *local_user, const char *server_user, char *host,
1.100 markus 362: Sensitive *sensitive)
1.20 markus 363: {
364: Authctxt authctxt;
365: int type;
1.39 markus 366:
1.73 markus 367: if (options.challenge_response_authentication)
1.39 markus 368: options.kbd_interactive_authentication = 1;
1.20 markus 369:
370: packet_start(SSH2_MSG_SERVICE_REQUEST);
371: packet_put_cstring("ssh-userauth");
372: packet_send();
1.108 markus 373: debug("SSH2_MSG_SERVICE_REQUEST sent");
1.20 markus 374: packet_write_wait();
1.91 markus 375: type = packet_read();
1.108 markus 376: if (type != SSH2_MSG_SERVICE_ACCEPT)
377: fatal("Server denied authentication request: %d", type);
1.20 markus 378: if (packet_remaining() > 0) {
1.91 markus 379: char *reply = packet_get_string(NULL);
1.108 markus 380: debug2("service_accept: %s", reply);
1.197 ! djm 381: free(reply);
1.20 markus 382: } else {
1.109 markus 383: debug2("buggy server: service_accept w/o service");
1.20 markus 384: }
1.90 markus 385: packet_check_eom();
1.108 markus 386: debug("SSH2_MSG_SERVICE_ACCEPT received");
1.20 markus 387:
1.53 markus 388: if (options.preferred_authentications == NULL)
389: options.preferred_authentications = authmethods_get();
390:
1.20 markus 391: /* setup authentication context */
1.82 markus 392: memset(&authctxt, 0, sizeof(authctxt));
1.117 markus 393: pubkey_prepare(&authctxt);
1.20 markus 394: authctxt.server_user = server_user;
1.68 markus 395: authctxt.local_user = local_user;
1.20 markus 396: authctxt.host = host;
397: authctxt.service = "ssh-connection"; /* service name */
398: authctxt.success = 0;
1.23 markus 399: authctxt.method = authmethod_lookup("none");
1.51 markus 400: authctxt.authlist = NULL;
1.121 markus 401: authctxt.methoddata = NULL;
1.100 markus 402: authctxt.sensitive = sensitive;
1.82 markus 403: authctxt.info_req_seen = 0;
1.23 markus 404: if (authctxt.method == NULL)
405: fatal("ssh_userauth2: internal error: cannot send userauth none request");
1.20 markus 406:
407: /* initial userauth request */
1.23 markus 408: userauth_none(&authctxt);
1.20 markus 409:
1.65 markus 410: dispatch_init(&input_userauth_error);
1.20 markus 411: dispatch_set(SSH2_MSG_USERAUTH_SUCCESS, &input_userauth_success);
412: dispatch_set(SSH2_MSG_USERAUTH_FAILURE, &input_userauth_failure);
1.35 markus 413: dispatch_set(SSH2_MSG_USERAUTH_BANNER, &input_userauth_banner);
1.20 markus 414: dispatch_run(DISPATCH_BLOCK, &authctxt.success, &authctxt); /* loop until success */
415:
1.117 markus 416: pubkey_cleanup(&authctxt);
1.119 markus 417: dispatch_range(SSH2_MSG_USERAUTH_MIN, SSH2_MSG_USERAUTH_MAX, NULL);
418:
1.109 markus 419: debug("Authentication succeeded (%s).", authctxt.method->name);
1.20 markus 420: }
1.119 markus 421:
1.20 markus 422: void
1.51 markus 423: userauth(Authctxt *authctxt, char *authlist)
424: {
1.170 djm 425: if (authctxt->method != NULL && authctxt->method->cleanup != NULL)
426: authctxt->method->cleanup(authctxt);
427:
1.197 ! djm 428: free(authctxt->methoddata);
! 429: authctxt->methoddata = NULL;
1.51 markus 430: if (authlist == NULL) {
431: authlist = authctxt->authlist;
432: } else {
1.197 ! djm 433: free(authctxt->authlist);
1.51 markus 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);
1.197 ! djm 481: free(msg);
1.166 djm 482: }
1.197 ! djm 483: free(raw);
! 484: free(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");
1.197 ! djm 495: free(authctxt->authlist);
! 496: authctxt->authlist = NULL;
1.172 djm 497: if (authctxt->method != NULL && authctxt->method->cleanup != NULL)
498: authctxt->method->cleanup(authctxt);
1.197 ! djm 499: free(authctxt->methoddata);
! 500: authctxt->methoddata = NULL;
1.20 markus 501: authctxt->success = 1; /* break out */
502: }
1.105 deraadt 503:
1.172 djm 504: void
505: input_userauth_success_unexpected(int type, u_int32_t seq, void *ctxt)
506: {
507: Authctxt *authctxt = ctxt;
508:
509: if (authctxt == NULL)
510: fatal("%s: no authentication context", __func__);
511:
512: fatal("Unexpected authentication success during %s.",
513: authctxt->method->name);
514: }
515:
1.169 djm 516: /* ARGSUSED */
1.20 markus 517: void
1.92 markus 518: input_userauth_failure(int type, u_int32_t seq, void *ctxt)
1.20 markus 519: {
520: Authctxt *authctxt = ctxt;
521: char *authlist = NULL;
522: int partial;
523:
524: if (authctxt == NULL)
525: fatal("input_userauth_failure: no authentication context");
526:
1.23 markus 527: authlist = packet_get_string(NULL);
1.20 markus 528: partial = packet_get_char();
1.90 markus 529: packet_check_eom();
1.20 markus 530:
1.193 markus 531: if (partial != 0) {
1.116 itojun 532: logit("Authenticated with partial success.");
1.193 markus 533: /* reset state */
534: pubkey_cleanup(authctxt);
535: pubkey_prepare(authctxt);
536: }
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);
1.197 ! djm 589: free(fp);
1.117 markus 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);
1.197 ! djm 605: free(pkalg);
! 606: free(pkblob);
1.51 markus 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) {
1.197 ! djm 744: free(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:
1.197 ! djm 755: free(oidv);
1.121 markus 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:
1.197 ! djm 784: free(recv_tok.value);
1.121 markus 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;
1.194 djm 801: OM_uint32 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 */
1.194 djm 814: (void)ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
1.140 djm 815: &recv_tok, &send_tok, NULL);
1.121 markus 816:
1.197 ! djm 817: free(recv_tok.value);
1.121 markus 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: char *msg;
828: char *lang;
829:
1.194 djm 830: /* maj */(void)packet_get_int();
831: /* min */(void)packet_get_int();
1.121 markus 832: msg=packet_get_string(NULL);
833: lang=packet_get_string(NULL);
834:
835: packet_check_eom();
836:
1.143 stevesk 837: debug("Server GSSAPI Error:\n%s", msg);
1.197 ! djm 838: free(msg);
! 839: free(lang);
1.121 markus 840: }
841: #endif /* GSSAPI */
1.20 markus 842:
1.1 markus 843: int
1.23 markus 844: userauth_none(Authctxt *authctxt)
845: {
846: /* initial userauth request */
847: packet_start(SSH2_MSG_USERAUTH_REQUEST);
848: packet_put_cstring(authctxt->server_user);
849: packet_put_cstring(authctxt->service);
850: packet_put_cstring(authctxt->method->name);
851: packet_send();
852: return 1;
853: }
854:
855: int
1.20 markus 856: userauth_passwd(Authctxt *authctxt)
1.1 markus 857: {
1.6 markus 858: static int attempt = 0;
1.99 markus 859: char prompt[150];
1.1 markus 860: char *password;
1.175 dtucker 861: const char *host = options.host_key_alias ? options.host_key_alias :
862: authctxt->host;
1.6 markus 863:
1.13 todd 864: if (attempt++ >= options.number_of_password_prompts)
1.6 markus 865: return 0;
1.13 todd 866:
1.87 deraadt 867: if (attempt != 1)
1.13 todd 868: error("Permission denied, please try again.");
1.1 markus 869:
1.43 itojun 870: snprintf(prompt, sizeof(prompt), "%.30s@%.128s's password: ",
1.175 dtucker 871: authctxt->server_user, host);
1.1 markus 872: password = read_passphrase(prompt, 0);
873: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1.20 markus 874: packet_put_cstring(authctxt->server_user);
875: packet_put_cstring(authctxt->service);
1.23 markus 876: packet_put_cstring(authctxt->method->name);
1.1 markus 877: packet_put_char(0);
1.49 markus 878: packet_put_cstring(password);
1.1 markus 879: memset(password, 0, strlen(password));
1.197 ! djm 880: free(password);
1.85 markus 881: packet_add_padding(64);
1.1 markus 882: packet_send();
1.99 markus 883:
1.104 deraadt 884: dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
1.99 markus 885: &input_userauth_passwd_changereq);
886:
1.1 markus 887: return 1;
888: }
1.169 djm 889:
1.99 markus 890: /*
891: * parse PASSWD_CHANGEREQ, prompt user and send SSH2_MSG_USERAUTH_REQUEST
892: */
1.169 djm 893: /* ARGSUSED */
1.99 markus 894: void
1.153 djm 895: input_userauth_passwd_changereq(int type, u_int32_t seqnr, void *ctxt)
1.99 markus 896: {
897: Authctxt *authctxt = ctxt;
898: char *info, *lang, *password = NULL, *retype = NULL;
899: char prompt[150];
1.175 dtucker 900: const char *host = options.host_key_alias ? options.host_key_alias :
901: authctxt->host;
1.99 markus 902:
903: debug2("input_userauth_passwd_changereq");
904:
905: if (authctxt == NULL)
906: fatal("input_userauth_passwd_changereq: "
907: "no authentication context");
908:
909: info = packet_get_string(NULL);
910: lang = packet_get_string(NULL);
911: if (strlen(info) > 0)
1.116 itojun 912: logit("%s", info);
1.197 ! djm 913: free(info);
! 914: free(lang);
1.99 markus 915: packet_start(SSH2_MSG_USERAUTH_REQUEST);
916: packet_put_cstring(authctxt->server_user);
917: packet_put_cstring(authctxt->service);
918: packet_put_cstring(authctxt->method->name);
919: packet_put_char(1); /* additional info */
1.104 deraadt 920: snprintf(prompt, sizeof(prompt),
1.99 markus 921: "Enter %.30s@%.128s's old password: ",
1.175 dtucker 922: authctxt->server_user, host);
1.99 markus 923: password = read_passphrase(prompt, 0);
924: packet_put_cstring(password);
925: memset(password, 0, strlen(password));
1.197 ! djm 926: free(password);
1.99 markus 927: password = NULL;
928: while (password == NULL) {
1.104 deraadt 929: snprintf(prompt, sizeof(prompt),
1.99 markus 930: "Enter %.30s@%.128s's new password: ",
1.175 dtucker 931: authctxt->server_user, host);
1.99 markus 932: password = read_passphrase(prompt, RP_ALLOW_EOF);
933: if (password == NULL) {
934: /* bail out */
935: return;
936: }
1.104 deraadt 937: snprintf(prompt, sizeof(prompt),
1.99 markus 938: "Retype %.30s@%.128s's new password: ",
1.175 dtucker 939: authctxt->server_user, host);
1.99 markus 940: retype = read_passphrase(prompt, 0);
941: if (strcmp(password, retype) != 0) {
942: memset(password, 0, strlen(password));
1.197 ! djm 943: free(password);
1.116 itojun 944: logit("Mismatch; try again, EOF to quit.");
1.99 markus 945: password = NULL;
946: }
947: memset(retype, 0, strlen(retype));
1.197 ! djm 948: free(retype);
1.99 markus 949: }
950: packet_put_cstring(password);
951: memset(password, 0, strlen(password));
1.197 ! djm 952: free(password);
1.99 markus 953: packet_add_padding(64);
954: packet_send();
1.104 deraadt 955:
956: dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
1.99 markus 957: &input_userauth_passwd_changereq);
1.117 markus 958: }
959:
1.170 djm 960: #ifdef JPAKE
961: static char *
962: pw_encrypt(const char *password, const char *crypt_scheme, const char *salt)
963: {
964: /* OpenBSD crypt(3) handles all of these */
965: if (strcmp(crypt_scheme, "crypt") == 0 ||
966: strcmp(crypt_scheme, "bcrypt") == 0 ||
967: strcmp(crypt_scheme, "md5crypt") == 0 ||
968: strcmp(crypt_scheme, "crypt-extended") == 0)
969: return xstrdup(crypt(password, salt));
970: error("%s: unsupported password encryption scheme \"%.100s\"",
971: __func__, crypt_scheme);
972: return NULL;
973: }
974:
975: static BIGNUM *
976: jpake_password_to_secret(Authctxt *authctxt, const char *crypt_scheme,
977: const char *salt)
978: {
979: char prompt[256], *password, *crypted;
980: u_char *secret;
981: u_int secret_len;
982: BIGNUM *ret;
983:
984: snprintf(prompt, sizeof(prompt), "%.30s@%.128s's password (JPAKE): ",
985: authctxt->server_user, authctxt->host);
986: password = read_passphrase(prompt, 0);
987:
988: if ((crypted = pw_encrypt(password, crypt_scheme, salt)) == NULL) {
989: logit("Disabling %s authentication", authctxt->method->name);
990: authctxt->method->enabled = NULL;
991: /* Continue with an empty password to fail gracefully */
992: crypted = xstrdup("");
993: }
994:
995: #ifdef JPAKE_DEBUG
996: debug3("%s: salt = %s", __func__, salt);
997: debug3("%s: scheme = %s", __func__, crypt_scheme);
998: debug3("%s: crypted = %s", __func__, crypted);
999: #endif
1000:
1001: if (hash_buffer(crypted, strlen(crypted), EVP_sha256(),
1002: &secret, &secret_len) != 0)
1003: fatal("%s: hash_buffer", __func__);
1004:
1005: bzero(password, strlen(password));
1006: bzero(crypted, strlen(crypted));
1.197 ! djm 1007: free(password);
! 1008: free(crypted);
1.170 djm 1009:
1010: if ((ret = BN_bin2bn(secret, secret_len, NULL)) == NULL)
1011: fatal("%s: BN_bin2bn (secret)", __func__);
1012: bzero(secret, secret_len);
1.197 ! djm 1013: free(secret);
1.170 djm 1014:
1015: return ret;
1016: }
1017:
1018: /* ARGSUSED */
1019: void
1020: input_userauth_jpake_server_step1(int type, u_int32_t seq, void *ctxt)
1021: {
1022: Authctxt *authctxt = ctxt;
1023: struct jpake_ctx *pctx = authctxt->methoddata;
1024: u_char *x3_proof, *x4_proof, *x2_s_proof;
1025: u_int x3_proof_len, x4_proof_len, x2_s_proof_len;
1026: char *crypt_scheme, *salt;
1027:
1028: /* Disable this message */
1029: dispatch_set(SSH2_MSG_USERAUTH_JPAKE_SERVER_STEP1, NULL);
1030:
1031: if ((pctx->g_x3 = BN_new()) == NULL ||
1032: (pctx->g_x4 = BN_new()) == NULL)
1033: fatal("%s: BN_new", __func__);
1034:
1035: /* Fetch step 1 values */
1036: crypt_scheme = packet_get_string(NULL);
1037: salt = packet_get_string(NULL);
1038: pctx->server_id = packet_get_string(&pctx->server_id_len);
1039: packet_get_bignum2(pctx->g_x3);
1040: packet_get_bignum2(pctx->g_x4);
1041: x3_proof = packet_get_string(&x3_proof_len);
1042: x4_proof = packet_get_string(&x4_proof_len);
1043: packet_check_eom();
1044:
1045: JPAKE_DEBUG_CTX((pctx, "step 1 received in %s", __func__));
1046:
1047: /* Obtain password and derive secret */
1048: pctx->s = jpake_password_to_secret(authctxt, crypt_scheme, salt);
1049: bzero(crypt_scheme, strlen(crypt_scheme));
1050: bzero(salt, strlen(salt));
1.197 ! djm 1051: free(crypt_scheme);
! 1052: free(salt);
1.170 djm 1053: JPAKE_DEBUG_BN((pctx->s, "%s: s = ", __func__));
1054:
1055: /* Calculate step 2 values */
1056: jpake_step2(pctx->grp, pctx->s, pctx->g_x1,
1057: pctx->g_x3, pctx->g_x4, pctx->x2,
1058: pctx->server_id, pctx->server_id_len,
1059: pctx->client_id, pctx->client_id_len,
1060: x3_proof, x3_proof_len,
1061: x4_proof, x4_proof_len,
1062: &pctx->a,
1063: &x2_s_proof, &x2_s_proof_len);
1064:
1065: bzero(x3_proof, x3_proof_len);
1066: bzero(x4_proof, x4_proof_len);
1.197 ! djm 1067: free(x3_proof);
! 1068: free(x4_proof);
1.170 djm 1069:
1070: JPAKE_DEBUG_CTX((pctx, "step 2 sending in %s", __func__));
1071:
1072: /* Send values for step 2 */
1073: packet_start(SSH2_MSG_USERAUTH_JPAKE_CLIENT_STEP2);
1074: packet_put_bignum2(pctx->a);
1075: packet_put_string(x2_s_proof, x2_s_proof_len);
1076: packet_send();
1077:
1078: bzero(x2_s_proof, x2_s_proof_len);
1.197 ! djm 1079: free(x2_s_proof);
1.170 djm 1080:
1081: /* Expect step 2 packet from peer */
1082: dispatch_set(SSH2_MSG_USERAUTH_JPAKE_SERVER_STEP2,
1083: input_userauth_jpake_server_step2);
1084: }
1085:
1086: /* ARGSUSED */
1087: void
1088: input_userauth_jpake_server_step2(int type, u_int32_t seq, void *ctxt)
1089: {
1090: Authctxt *authctxt = ctxt;
1091: struct jpake_ctx *pctx = authctxt->methoddata;
1092: u_char *x4_s_proof;
1093: u_int x4_s_proof_len;
1094:
1095: /* Disable this message */
1096: dispatch_set(SSH2_MSG_USERAUTH_JPAKE_SERVER_STEP2, NULL);
1097:
1098: if ((pctx->b = BN_new()) == NULL)
1099: fatal("%s: BN_new", __func__);
1100:
1101: /* Fetch step 2 values */
1102: packet_get_bignum2(pctx->b);
1103: x4_s_proof = packet_get_string(&x4_s_proof_len);
1104: packet_check_eom();
1105:
1106: JPAKE_DEBUG_CTX((pctx, "step 2 received in %s", __func__));
1107:
1108: /* Derive shared key and calculate confirmation hash */
1109: jpake_key_confirm(pctx->grp, pctx->s, pctx->b,
1110: pctx->x2, pctx->g_x1, pctx->g_x2, pctx->g_x3, pctx->g_x4,
1111: pctx->client_id, pctx->client_id_len,
1112: pctx->server_id, pctx->server_id_len,
1113: session_id2, session_id2_len,
1114: x4_s_proof, x4_s_proof_len,
1115: &pctx->k,
1116: &pctx->h_k_cid_sessid, &pctx->h_k_cid_sessid_len);
1117:
1118: bzero(x4_s_proof, x4_s_proof_len);
1.197 ! djm 1119: free(x4_s_proof);
1.170 djm 1120:
1121: JPAKE_DEBUG_CTX((pctx, "confirm sending in %s", __func__));
1122:
1123: /* Send key confirmation proof */
1124: packet_start(SSH2_MSG_USERAUTH_JPAKE_CLIENT_CONFIRM);
1125: packet_put_string(pctx->h_k_cid_sessid, pctx->h_k_cid_sessid_len);
1126: packet_send();
1127:
1128: /* Expect confirmation from peer */
1129: dispatch_set(SSH2_MSG_USERAUTH_JPAKE_SERVER_CONFIRM,
1130: input_userauth_jpake_server_confirm);
1131: }
1132:
1133: /* ARGSUSED */
1134: void
1135: input_userauth_jpake_server_confirm(int type, u_int32_t seq, void *ctxt)
1136: {
1137: Authctxt *authctxt = ctxt;
1138: struct jpake_ctx *pctx = authctxt->methoddata;
1139:
1140: /* Disable this message */
1141: dispatch_set(SSH2_MSG_USERAUTH_JPAKE_SERVER_CONFIRM, NULL);
1142:
1143: pctx->h_k_sid_sessid = packet_get_string(&pctx->h_k_sid_sessid_len);
1144: packet_check_eom();
1145:
1146: JPAKE_DEBUG_CTX((pctx, "confirm received in %s", __func__));
1147:
1148: /* Verify expected confirmation hash */
1149: if (jpake_check_confirm(pctx->k,
1150: pctx->server_id, pctx->server_id_len,
1151: session_id2, session_id2_len,
1152: pctx->h_k_sid_sessid, pctx->h_k_sid_sessid_len) == 1)
1153: debug("%s: %s success", __func__, authctxt->method->name);
1154: else {
1155: debug("%s: confirmation mismatch", __func__);
1156: /* XXX stash this so if auth succeeds then we can warn/kill */
1157: }
1158:
1159: userauth_jpake_cleanup(authctxt);
1160: }
1161: #endif /* JPAKE */
1162:
1.117 markus 1163: static int
1164: identity_sign(Identity *id, u_char **sigp, u_int *lenp,
1165: u_char *data, u_int datalen)
1166: {
1167: Key *prv;
1168: int ret;
1.99 markus 1169:
1.117 markus 1170: /* the agent supports this key */
1171: if (id->ac)
1172: return (ssh_agent_sign(id->ac, id->key, sigp, lenp,
1173: data, datalen));
1174: /*
1175: * we have already loaded the private key or
1176: * the private key is stored in external hardware
1177: */
1178: if (id->isprivate || (id->key->flags & KEY_FLAG_EXT))
1179: return (key_sign(id->key, sigp, lenp, data, datalen));
1180: /* load the private key from the file */
1.191 dtucker 1181: if ((prv = load_identity_file(id->filename, id->userprovided)) == NULL)
1.117 markus 1182: return (-1);
1183: ret = key_sign(prv, sigp, lenp, data, datalen);
1184: key_free(prv);
1185: return (ret);
1.51 markus 1186: }
1187:
1.76 itojun 1188: static int
1.117 markus 1189: sign_and_send_pubkey(Authctxt *authctxt, Identity *id)
1.1 markus 1190: {
1191: Buffer b;
1.32 markus 1192: u_char *blob, *signature;
1.96 markus 1193: u_int bloblen, slen;
1.120 markus 1194: u_int skip = 0;
1.17 markus 1195: int ret = -1;
1.23 markus 1196: int have_sig = 1;
1.182 djm 1197: char *fp;
1.1 markus 1198:
1.182 djm 1199: fp = key_fingerprint(id->key, SSH_FP_MD5, SSH_FP_HEX);
1200: debug3("sign_and_send_pubkey: %s %s", key_type(id->key), fp);
1.197 ! djm 1201: free(fp);
1.51 markus 1202:
1.117 markus 1203: if (key_to_blob(id->key, &blob, &bloblen) == 0) {
1.28 markus 1204: /* we cannot handle this key */
1.30 markus 1205: debug3("sign_and_send_pubkey: cannot handle key");
1.28 markus 1206: return 0;
1207: }
1.1 markus 1208: /* data to be signed */
1209: buffer_init(&b);
1.26 markus 1210: if (datafellows & SSH_OLD_SESSIONID) {
1211: buffer_append(&b, session_id2, session_id2_len);
1.41 stevesk 1212: skip = session_id2_len;
1.26 markus 1213: } else {
1.14 markus 1214: buffer_put_string(&b, session_id2, session_id2_len);
1215: skip = buffer_len(&b);
1216: }
1.1 markus 1217: buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
1.20 markus 1218: buffer_put_cstring(&b, authctxt->server_user);
1.10 markus 1219: buffer_put_cstring(&b,
1.30 markus 1220: datafellows & SSH_BUG_PKSERVICE ?
1.10 markus 1221: "ssh-userauth" :
1.20 markus 1222: authctxt->service);
1.30 markus 1223: if (datafellows & SSH_BUG_PKAUTH) {
1224: buffer_put_char(&b, have_sig);
1225: } else {
1226: buffer_put_cstring(&b, authctxt->method->name);
1227: buffer_put_char(&b, have_sig);
1.117 markus 1228: buffer_put_cstring(&b, key_ssh_name(id->key));
1.30 markus 1229: }
1.1 markus 1230: buffer_put_string(&b, blob, bloblen);
1231:
1232: /* generate signature */
1.117 markus 1233: ret = identity_sign(id, &signature, &slen,
1.51 markus 1234: buffer_ptr(&b), buffer_len(&b));
1.17 markus 1235: if (ret == -1) {
1.197 ! djm 1236: free(blob);
1.17 markus 1237: buffer_free(&b);
1238: return 0;
1239: }
1.28 markus 1240: #ifdef DEBUG_PK
1.1 markus 1241: buffer_dump(&b);
1242: #endif
1.30 markus 1243: if (datafellows & SSH_BUG_PKSERVICE) {
1.10 markus 1244: buffer_clear(&b);
1245: buffer_append(&b, session_id2, session_id2_len);
1.51 markus 1246: skip = session_id2_len;
1.10 markus 1247: buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
1.20 markus 1248: buffer_put_cstring(&b, authctxt->server_user);
1249: buffer_put_cstring(&b, authctxt->service);
1.23 markus 1250: buffer_put_cstring(&b, authctxt->method->name);
1251: buffer_put_char(&b, have_sig);
1.30 markus 1252: if (!(datafellows & SSH_BUG_PKAUTH))
1.117 markus 1253: buffer_put_cstring(&b, key_ssh_name(id->key));
1.10 markus 1254: buffer_put_string(&b, blob, bloblen);
1255: }
1.197 ! djm 1256: free(blob);
1.51 markus 1257:
1.1 markus 1258: /* append signature */
1259: buffer_put_string(&b, signature, slen);
1.197 ! djm 1260: free(signature);
1.1 markus 1261:
1262: /* skip session id and packet type */
1.14 markus 1263: if (buffer_len(&b) < skip + 1)
1.20 markus 1264: fatal("userauth_pubkey: internal error");
1.14 markus 1265: buffer_consume(&b, skip + 1);
1.1 markus 1266:
1267: /* put remaining data from buffer into packet */
1268: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1269: packet_put_raw(buffer_ptr(&b), buffer_len(&b));
1270: buffer_free(&b);
1271: packet_send();
1.17 markus 1272:
1273: return 1;
1.16 markus 1274: }
1275:
1.76 itojun 1276: static int
1.117 markus 1277: send_pubkey_test(Authctxt *authctxt, Identity *id)
1.20 markus 1278: {
1.51 markus 1279: u_char *blob;
1.97 markus 1280: u_int bloblen, have_sig = 0;
1.20 markus 1281:
1.51 markus 1282: debug3("send_pubkey_test");
1.16 markus 1283:
1.117 markus 1284: if (key_to_blob(id->key, &blob, &bloblen) == 0) {
1.51 markus 1285: /* we cannot handle this key */
1286: debug3("send_pubkey_test: cannot handle key");
1.16 markus 1287: return 0;
1288: }
1.51 markus 1289: /* register callback for USERAUTH_PK_OK message */
1290: dispatch_set(SSH2_MSG_USERAUTH_PK_OK, &input_userauth_pk_ok);
1291:
1292: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1293: packet_put_cstring(authctxt->server_user);
1294: packet_put_cstring(authctxt->service);
1295: packet_put_cstring(authctxt->method->name);
1296: packet_put_char(have_sig);
1297: if (!(datafellows & SSH_BUG_PKAUTH))
1.117 markus 1298: packet_put_cstring(key_ssh_name(id->key));
1.51 markus 1299: packet_put_string(blob, bloblen);
1.197 ! djm 1300: free(blob);
1.51 markus 1301: packet_send();
1302: return 1;
1303: }
1304:
1.76 itojun 1305: static Key *
1.191 dtucker 1306: load_identity_file(char *filename, int userprovided)
1.51 markus 1307: {
1308: Key *private;
1309: char prompt[300], *passphrase;
1.178 dtucker 1310: int perm_ok = 0, quit, i;
1.52 markus 1311: struct stat st;
1.16 markus 1312:
1.52 markus 1313: if (stat(filename, &st) < 0) {
1.191 dtucker 1314: (userprovided ? logit : debug3)("no such identity: %s: %s",
1315: filename, strerror(errno));
1.52 markus 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));
1.197 ! djm 1337: free(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: {
1.190 djm 1355: Identity *id, *id2, *tmp;
1.117 markus 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:
1.190 djm 1367: /* list of keys stored in the filesystem and PKCS#11 */
1.117 markus 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]);
1.192 dtucker 1378: id->userprovided = options.identity_file_userprovided[i];
1.117 markus 1379: TAILQ_INSERT_TAIL(&files, id, next);
1.190 djm 1380: }
1381: /* Prefer PKCS11 keys that are explicitly listed */
1382: TAILQ_FOREACH_SAFE(id, &files, next, tmp) {
1383: if (id->key == NULL || (id->key->flags & KEY_FLAG_EXT) == 0)
1384: continue;
1385: found = 0;
1386: TAILQ_FOREACH(id2, &files, next) {
1387: if (id2->key == NULL ||
1388: (id2->key->flags & KEY_FLAG_EXT) != 0)
1389: continue;
1390: if (key_equal(id->key, id2->key)) {
1391: TAILQ_REMOVE(&files, id, next);
1392: TAILQ_INSERT_TAIL(preferred, id, next);
1393: found = 1;
1394: break;
1395: }
1396: }
1397: /* If IdentitiesOnly set and key not found then don't use it */
1398: if (!found && options.identities_only) {
1399: TAILQ_REMOVE(&files, id, next);
1.195 djm 1400: bzero(id, sizeof(*id));
1.190 djm 1401: free(id);
1402: }
1.117 markus 1403: }
1404: /* list of keys supported by the agent */
1405: if ((ac = ssh_get_authentication_connection())) {
1406: for (key = ssh_get_first_identity(ac, &comment, 2);
1407: key != NULL;
1408: key = ssh_get_next_identity(ac, &comment, 2)) {
1409: found = 0;
1410: TAILQ_FOREACH(id, &files, next) {
1.133 djm 1411: /* agent keys from the config file are preferred */
1.117 markus 1412: if (key_equal(key, id->key)) {
1413: key_free(key);
1.197 ! djm 1414: free(comment);
1.117 markus 1415: TAILQ_REMOVE(&files, id, next);
1416: TAILQ_INSERT_TAIL(preferred, id, next);
1417: id->ac = ac;
1418: found = 1;
1419: break;
1420: }
1421: }
1.135 markus 1422: if (!found && !options.identities_only) {
1.150 djm 1423: id = xcalloc(1, sizeof(*id));
1.117 markus 1424: id->key = key;
1425: id->filename = comment;
1426: id->ac = ac;
1427: TAILQ_INSERT_TAIL(&agent, id, next);
1428: }
1429: }
1430: /* append remaining agent keys */
1431: for (id = TAILQ_FIRST(&agent); id; id = TAILQ_FIRST(&agent)) {
1432: TAILQ_REMOVE(&agent, id, next);
1433: TAILQ_INSERT_TAIL(preferred, id, next);
1434: }
1435: authctxt->agent = ac;
1436: }
1437: /* append remaining keys from the config file */
1438: for (id = TAILQ_FIRST(&files); id; id = TAILQ_FIRST(&files)) {
1439: TAILQ_REMOVE(&files, id, next);
1440: TAILQ_INSERT_TAIL(preferred, id, next);
1441: }
1442: TAILQ_FOREACH(id, preferred, next) {
1.191 dtucker 1443: debug2("key: %s (%p),%s", id->filename, id->key,
1444: id->userprovided ? " explicit" : "");
1.117 markus 1445: }
1.17 markus 1446: }
1447:
1.117 markus 1448: static void
1449: pubkey_cleanup(Authctxt *authctxt)
1.51 markus 1450: {
1.117 markus 1451: Identity *id;
1.51 markus 1452:
1.117 markus 1453: if (authctxt->agent != NULL)
1454: ssh_close_authentication_connection(authctxt->agent);
1455: for (id = TAILQ_FIRST(&authctxt->keys); id;
1456: id = TAILQ_FIRST(&authctxt->keys)) {
1457: TAILQ_REMOVE(&authctxt->keys, id, next);
1458: if (id->key)
1459: key_free(id->key);
1.197 ! djm 1460: free(id->filename);
! 1461: free(id);
1.117 markus 1462: }
1.1 markus 1463: }
1464:
1.20 markus 1465: int
1466: userauth_pubkey(Authctxt *authctxt)
1467: {
1.117 markus 1468: Identity *id;
1.20 markus 1469: int sent = 0;
1470:
1.117 markus 1471: while ((id = TAILQ_FIRST(&authctxt->keys))) {
1472: if (id->tried++)
1473: return (0);
1.127 markus 1474: /* move key to the end of the queue */
1.117 markus 1475: TAILQ_REMOVE(&authctxt->keys, id, next);
1476: TAILQ_INSERT_TAIL(&authctxt->keys, id, next);
1477: /*
1478: * send a test message if we have the public key. for
1479: * encrypted keys we cannot do this and have to load the
1480: * private key instead
1481: */
1482: if (id->key && id->key->type != KEY_RSA1) {
1.181 djm 1483: debug("Offering %s public key: %s", key_type(id->key),
1484: id->filename);
1.117 markus 1485: sent = send_pubkey_test(authctxt, id);
1486: } else if (id->key == NULL) {
1487: debug("Trying private key: %s", id->filename);
1.191 dtucker 1488: id->key = load_identity_file(id->filename,
1489: id->userprovided);
1.117 markus 1490: if (id->key != NULL) {
1491: id->isprivate = 1;
1492: sent = sign_and_send_pubkey(authctxt, id);
1493: key_free(id->key);
1494: id->key = NULL;
1.51 markus 1495: }
1496: }
1.117 markus 1497: if (sent)
1498: return (sent);
1.28 markus 1499: }
1.117 markus 1500: return (0);
1.20 markus 1501: }
1502:
1.23 markus 1503: /*
1504: * Send userauth request message specifying keyboard-interactive method.
1505: */
1506: int
1507: userauth_kbdint(Authctxt *authctxt)
1508: {
1509: static int attempt = 0;
1510:
1511: if (attempt++ >= options.number_of_password_prompts)
1512: return 0;
1.82 markus 1513: /* disable if no SSH2_MSG_USERAUTH_INFO_REQUEST has been seen */
1514: if (attempt > 1 && !authctxt->info_req_seen) {
1515: debug3("userauth_kbdint: disable: no info_req_seen");
1516: dispatch_set(SSH2_MSG_USERAUTH_INFO_REQUEST, NULL);
1517: return 0;
1518: }
1.23 markus 1519:
1520: debug2("userauth_kbdint");
1521: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1522: packet_put_cstring(authctxt->server_user);
1523: packet_put_cstring(authctxt->service);
1524: packet_put_cstring(authctxt->method->name);
1525: packet_put_cstring(""); /* lang */
1526: packet_put_cstring(options.kbd_interactive_devices ?
1527: options.kbd_interactive_devices : "");
1528: packet_send();
1529:
1530: dispatch_set(SSH2_MSG_USERAUTH_INFO_REQUEST, &input_userauth_info_req);
1531: return 1;
1532: }
1533:
1534: /*
1.46 markus 1535: * parse INFO_REQUEST, prompt user and send INFO_RESPONSE
1.23 markus 1536: */
1537: void
1.92 markus 1538: input_userauth_info_req(int type, u_int32_t seq, void *ctxt)
1.23 markus 1539: {
1540: Authctxt *authctxt = ctxt;
1.46 markus 1541: char *name, *inst, *lang, *prompt, *response;
1.32 markus 1542: u_int num_prompts, i;
1.23 markus 1543: int echo = 0;
1544:
1545: debug2("input_userauth_info_req");
1546:
1547: if (authctxt == NULL)
1548: fatal("input_userauth_info_req: no authentication context");
1.82 markus 1549:
1550: authctxt->info_req_seen = 1;
1.23 markus 1551:
1552: name = packet_get_string(NULL);
1553: inst = packet_get_string(NULL);
1554: lang = packet_get_string(NULL);
1555: if (strlen(name) > 0)
1.116 itojun 1556: logit("%s", name);
1.23 markus 1557: if (strlen(inst) > 0)
1.116 itojun 1558: logit("%s", inst);
1.197 ! djm 1559: free(name);
! 1560: free(inst);
! 1561: free(lang);
1.23 markus 1562:
1563: num_prompts = packet_get_int();
1564: /*
1565: * Begin to build info response packet based on prompts requested.
1566: * We commit to providing the correct number of responses, so if
1567: * further on we run into a problem that prevents this, we have to
1568: * be sure and clean this up and send a correct error response.
1569: */
1570: packet_start(SSH2_MSG_USERAUTH_INFO_RESPONSE);
1571: packet_put_int(num_prompts);
1572:
1.73 markus 1573: debug2("input_userauth_info_req: num_prompts %d", num_prompts);
1.23 markus 1574: for (i = 0; i < num_prompts; i++) {
1575: prompt = packet_get_string(NULL);
1576: echo = packet_get_char();
1577:
1.77 markus 1578: response = read_passphrase(prompt, echo ? RP_ECHO : 0);
1.23 markus 1579:
1.49 markus 1580: packet_put_cstring(response);
1.23 markus 1581: memset(response, 0, strlen(response));
1.197 ! djm 1582: free(response);
! 1583: free(prompt);
1.23 markus 1584: }
1.90 markus 1585: packet_check_eom(); /* done with parsing incoming message. */
1.23 markus 1586:
1.85 markus 1587: packet_add_padding(64);
1.23 markus 1588: packet_send();
1.68 markus 1589: }
1590:
1.100 markus 1591: static int
1.105 deraadt 1592: ssh_keysign(Key *key, u_char **sigp, u_int *lenp,
1.100 markus 1593: u_char *data, u_int datalen)
1594: {
1595: Buffer b;
1.101 markus 1596: struct stat st;
1.100 markus 1597: pid_t pid;
1.103 markus 1598: int to[2], from[2], status, version = 2;
1.100 markus 1599:
1.109 markus 1600: debug2("ssh_keysign called");
1.100 markus 1601:
1.101 markus 1602: if (stat(_PATH_SSH_KEY_SIGN, &st) < 0) {
1.179 dtucker 1603: error("ssh_keysign: not installed: %s", strerror(errno));
1.101 markus 1604: return -1;
1605: }
1.100 markus 1606: if (fflush(stdout) != 0)
1607: error("ssh_keysign: fflush: %s", strerror(errno));
1608: if (pipe(to) < 0) {
1609: error("ssh_keysign: pipe: %s", strerror(errno));
1610: return -1;
1611: }
1612: if (pipe(from) < 0) {
1613: error("ssh_keysign: pipe: %s", strerror(errno));
1614: return -1;
1615: }
1616: if ((pid = fork()) < 0) {
1617: error("ssh_keysign: fork: %s", strerror(errno));
1618: return -1;
1619: }
1620: if (pid == 0) {
1.174 dtucker 1621: /* keep the socket on exec */
1622: fcntl(packet_get_connection_in(), F_SETFD, 0);
1.155 markus 1623: permanently_drop_suid(getuid());
1.100 markus 1624: close(from[0]);
1625: if (dup2(from[1], STDOUT_FILENO) < 0)
1626: fatal("ssh_keysign: dup2: %s", strerror(errno));
1627: close(to[1]);
1628: if (dup2(to[0], STDIN_FILENO) < 0)
1629: fatal("ssh_keysign: dup2: %s", strerror(errno));
1.103 markus 1630: close(from[1]);
1631: close(to[0]);
1.102 markus 1632: execl(_PATH_SSH_KEY_SIGN, _PATH_SSH_KEY_SIGN, (char *) 0);
1.100 markus 1633: fatal("ssh_keysign: exec(%s): %s", _PATH_SSH_KEY_SIGN,
1634: strerror(errno));
1635: }
1636: close(from[1]);
1637: close(to[0]);
1638:
1639: buffer_init(&b);
1.103 markus 1640: buffer_put_int(&b, packet_get_connection_in()); /* send # of socket */
1.100 markus 1641: buffer_put_string(&b, data, datalen);
1.131 djm 1642: if (ssh_msg_send(to[1], version, &b) == -1)
1643: fatal("ssh_keysign: couldn't send request");
1.100 markus 1644:
1.110 djm 1645: if (ssh_msg_recv(from[0], &b) < 0) {
1.101 markus 1646: error("ssh_keysign: no reply");
1.134 markus 1647: buffer_free(&b);
1.100 markus 1648: return -1;
1649: }
1.101 markus 1650: close(from[0]);
1651: close(to[1]);
1652:
1.103 markus 1653: while (waitpid(pid, &status, 0) < 0)
1654: if (errno != EINTR)
1655: break;
1.101 markus 1656:
1.100 markus 1657: if (buffer_get_char(&b) != version) {
1.101 markus 1658: error("ssh_keysign: bad version");
1.134 markus 1659: buffer_free(&b);
1.100 markus 1660: return -1;
1661: }
1662: *sigp = buffer_get_string(&b, lenp);
1.134 markus 1663: buffer_free(&b);
1.100 markus 1664:
1665: return 0;
1666: }
1667:
1.68 markus 1668: int
1669: userauth_hostbased(Authctxt *authctxt)
1670: {
1671: Key *private = NULL;
1.100 markus 1672: Sensitive *sensitive = authctxt->sensitive;
1.68 markus 1673: Buffer b;
1674: u_char *signature, *blob;
1.179 dtucker 1675: char *chost, *pkalg, *p;
1.72 markus 1676: const char *service;
1.68 markus 1677: u_int blen, slen;
1.176 dtucker 1678: int ok, i, found = 0;
1.68 markus 1679:
1680: /* check for a useful key */
1.100 markus 1681: for (i = 0; i < sensitive->nkeys; i++) {
1682: private = sensitive->keys[i];
1.68 markus 1683: if (private && private->type != KEY_RSA1) {
1684: found = 1;
1685: /* we take and free the key */
1.100 markus 1686: sensitive->keys[i] = NULL;
1.68 markus 1687: break;
1688: }
1689: }
1690: if (!found) {
1.109 markus 1691: debug("No more client hostkeys for hostbased authentication.");
1.68 markus 1692: return 0;
1693: }
1694: if (key_to_blob(private, &blob, &blen) == 0) {
1695: key_free(private);
1696: return 0;
1697: }
1.84 markus 1698: /* figure out a name for the client host */
1.179 dtucker 1699: p = get_local_name(packet_get_connection_in());
1.84 markus 1700: if (p == NULL) {
1701: error("userauth_hostbased: cannot get local ipaddr/name");
1702: key_free(private);
1.197 ! djm 1703: free(blob);
1.84 markus 1704: return 0;
1705: }
1.150 djm 1706: xasprintf(&chost, "%s.", p);
1.84 markus 1707: debug2("userauth_hostbased: chost %s", chost);
1.197 ! djm 1708: free(p);
1.84 markus 1709:
1.72 markus 1710: service = datafellows & SSH_BUG_HBSERVICE ? "ssh-userauth" :
1711: authctxt->service;
1.68 markus 1712: pkalg = xstrdup(key_ssh_name(private));
1713: buffer_init(&b);
1714: /* construct data */
1.72 markus 1715: buffer_put_string(&b, session_id2, session_id2_len);
1.68 markus 1716: buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
1717: buffer_put_cstring(&b, authctxt->server_user);
1.72 markus 1718: buffer_put_cstring(&b, service);
1.68 markus 1719: buffer_put_cstring(&b, authctxt->method->name);
1720: buffer_put_cstring(&b, pkalg);
1721: buffer_put_string(&b, blob, blen);
1722: buffer_put_cstring(&b, chost);
1723: buffer_put_cstring(&b, authctxt->local_user);
1724: #ifdef DEBUG_PK
1725: buffer_dump(&b);
1726: #endif
1.100 markus 1727: if (sensitive->external_keysign)
1728: ok = ssh_keysign(private, &signature, &slen,
1729: buffer_ptr(&b), buffer_len(&b));
1730: else
1731: ok = key_sign(private, &signature, &slen,
1732: buffer_ptr(&b), buffer_len(&b));
1.68 markus 1733: key_free(private);
1734: buffer_free(&b);
1735: if (ok != 0) {
1736: error("key_sign failed");
1.197 ! djm 1737: free(chost);
! 1738: free(pkalg);
! 1739: free(blob);
1.68 markus 1740: return 0;
1741: }
1742: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1743: packet_put_cstring(authctxt->server_user);
1744: packet_put_cstring(authctxt->service);
1745: packet_put_cstring(authctxt->method->name);
1746: packet_put_cstring(pkalg);
1747: packet_put_string(blob, blen);
1748: packet_put_cstring(chost);
1749: packet_put_cstring(authctxt->local_user);
1750: packet_put_string(signature, slen);
1751: memset(signature, 's', slen);
1.197 ! djm 1752: free(signature);
! 1753: free(chost);
! 1754: free(pkalg);
! 1755: free(blob);
1.68 markus 1756:
1757: packet_send();
1758: return 1;
1.23 markus 1759: }
1.20 markus 1760:
1.170 djm 1761: #ifdef JPAKE
1762: int
1763: userauth_jpake(Authctxt *authctxt)
1764: {
1765: struct jpake_ctx *pctx;
1766: u_char *x1_proof, *x2_proof;
1767: u_int x1_proof_len, x2_proof_len;
1768: static int attempt = 0; /* XXX share with userauth_password's? */
1769:
1770: if (attempt++ >= options.number_of_password_prompts)
1771: return 0;
1772: if (attempt != 1)
1773: error("Permission denied, please try again.");
1774:
1775: if (authctxt->methoddata != NULL)
1776: fatal("%s: authctxt->methoddata already set (%p)",
1777: __func__, authctxt->methoddata);
1778:
1779: authctxt->methoddata = pctx = jpake_new();
1780:
1781: /*
1782: * Send request immediately, to get the protocol going while
1783: * we do the initial computations.
1784: */
1785: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1786: packet_put_cstring(authctxt->server_user);
1787: packet_put_cstring(authctxt->service);
1788: packet_put_cstring(authctxt->method->name);
1789: packet_send();
1790: packet_write_wait();
1791:
1792: jpake_step1(pctx->grp,
1793: &pctx->client_id, &pctx->client_id_len,
1794: &pctx->x1, &pctx->x2, &pctx->g_x1, &pctx->g_x2,
1795: &x1_proof, &x1_proof_len,
1796: &x2_proof, &x2_proof_len);
1797:
1798: JPAKE_DEBUG_CTX((pctx, "step 1 sending in %s", __func__));
1799:
1800: packet_start(SSH2_MSG_USERAUTH_JPAKE_CLIENT_STEP1);
1801: packet_put_string(pctx->client_id, pctx->client_id_len);
1802: packet_put_bignum2(pctx->g_x1);
1803: packet_put_bignum2(pctx->g_x2);
1804: packet_put_string(x1_proof, x1_proof_len);
1805: packet_put_string(x2_proof, x2_proof_len);
1806: packet_send();
1807:
1808: bzero(x1_proof, x1_proof_len);
1809: bzero(x2_proof, x2_proof_len);
1.197 ! djm 1810: free(x1_proof);
! 1811: free(x2_proof);
1.170 djm 1812:
1813: /* Expect step 1 packet from peer */
1814: dispatch_set(SSH2_MSG_USERAUTH_JPAKE_SERVER_STEP1,
1815: input_userauth_jpake_server_step1);
1.172 djm 1816: dispatch_set(SSH2_MSG_USERAUTH_SUCCESS,
1817: &input_userauth_success_unexpected);
1.170 djm 1818:
1819: return 1;
1820: }
1821:
1822: void
1823: userauth_jpake_cleanup(Authctxt *authctxt)
1824: {
1825: debug3("%s: clean up", __func__);
1826: if (authctxt->methoddata != NULL) {
1827: jpake_free(authctxt->methoddata);
1828: authctxt->methoddata = NULL;
1829: }
1.172 djm 1830: dispatch_set(SSH2_MSG_USERAUTH_SUCCESS, &input_userauth_success);
1.170 djm 1831: }
1832: #endif /* JPAKE */
1833:
1.20 markus 1834: /* find auth method */
1835:
1836: /*
1837: * given auth method name, if configurable options permit this method fill
1838: * in auth_ident field and return true, otherwise return false.
1839: */
1.76 itojun 1840: static int
1.20 markus 1841: authmethod_is_enabled(Authmethod *method)
1842: {
1843: if (method == NULL)
1844: return 0;
1845: /* return false if options indicate this method is disabled */
1846: if (method->enabled == NULL || *method->enabled == 0)
1847: return 0;
1848: /* return false if batch mode is enabled but method needs interactive mode */
1849: if (method->batch_flag != NULL && *method->batch_flag != 0)
1850: return 0;
1851: return 1;
1852: }
1853:
1.76 itojun 1854: static Authmethod *
1.20 markus 1855: authmethod_lookup(const char *name)
1.1 markus 1856: {
1.20 markus 1857: Authmethod *method = NULL;
1858: if (name != NULL)
1859: for (method = authmethods; method->name != NULL; method++)
1860: if (strcmp(name, method->name) == 0)
1861: return method;
1862: debug2("Unrecognized authentication method name: %s", name ? name : "NULL");
1863: return NULL;
1864: }
1.1 markus 1865:
1.53 markus 1866: /* XXX internal state */
1867: static Authmethod *current = NULL;
1868: static char *supported = NULL;
1869: static char *preferred = NULL;
1.105 deraadt 1870:
1.20 markus 1871: /*
1872: * Given the authentication method list sent by the server, return the
1873: * next method we should try. If the server initially sends a nil list,
1.67 markus 1874: * use a built-in default list.
1.41 stevesk 1875: */
1.76 itojun 1876: static Authmethod *
1.20 markus 1877: authmethod_get(char *authlist)
1878: {
1.53 markus 1879: char *name = NULL;
1.97 markus 1880: u_int next;
1.41 stevesk 1881:
1.20 markus 1882: /* Use a suitable default if we're passed a nil list. */
1883: if (authlist == NULL || strlen(authlist) == 0)
1.53 markus 1884: authlist = options.preferred_authentications;
1.20 markus 1885:
1.53 markus 1886: if (supported == NULL || strcmp(authlist, supported) != 0) {
1887: debug3("start over, passed a different list %s", authlist);
1.197 ! djm 1888: free(supported);
1.53 markus 1889: supported = xstrdup(authlist);
1890: preferred = options.preferred_authentications;
1891: debug3("preferred %s", preferred);
1892: current = NULL;
1893: } else if (current != NULL && authmethod_is_enabled(current))
1894: return current;
1.20 markus 1895:
1.53 markus 1896: for (;;) {
1897: if ((name = match_list(preferred, supported, &next)) == NULL) {
1.109 markus 1898: debug("No more authentication methods to try.");
1.53 markus 1899: current = NULL;
1900: return NULL;
1901: }
1902: preferred += next;
1.23 markus 1903: debug3("authmethod_lookup %s", name);
1.53 markus 1904: debug3("remaining preferred: %s", preferred);
1905: if ((current = authmethod_lookup(name)) != NULL &&
1906: authmethod_is_enabled(current)) {
1.23 markus 1907: debug3("authmethod_is_enabled %s", name);
1.109 markus 1908: debug("Next authentication method: %s", name);
1.197 ! djm 1909: free(name);
1.53 markus 1910: return current;
1.23 markus 1911: }
1.1 markus 1912: }
1.53 markus 1913: }
1.1 markus 1914:
1.79 stevesk 1915: static char *
1.53 markus 1916: authmethods_get(void)
1917: {
1918: Authmethod *method = NULL;
1.93 markus 1919: Buffer b;
1920: char *list;
1.27 provos 1921:
1.93 markus 1922: buffer_init(&b);
1.53 markus 1923: for (method = authmethods; method->name != NULL; method++) {
1924: if (authmethod_is_enabled(method)) {
1.93 markus 1925: if (buffer_len(&b) > 0)
1926: buffer_append(&b, ",", 1);
1927: buffer_append(&b, method->name, strlen(method->name));
1.53 markus 1928: }
1929: }
1.93 markus 1930: buffer_append(&b, "\0", 1);
1931: list = xstrdup(buffer_ptr(&b));
1932: buffer_free(&b);
1933: return list;
1.1 markus 1934: }
1.170 djm 1935:
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