Annotation of src/usr.bin/ssh/sshconnect2.c, Revision 1.183
1.183 ! djm 1: /* $OpenBSD: sshconnect2.c,v 1.182 2010/04/16 01:47:26 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"
1.171 djm 66: #include "schnorr.h"
1.170 djm 67: #include "jpake.h"
1.22 provos 68:
1.121 markus 69: #ifdef GSSAPI
70: #include "ssh-gss.h"
71: #endif
72:
1.1 markus 73: /* import */
74: extern char *client_version_string;
75: extern char *server_version_string;
76: extern Options options;
77:
78: /*
79: * SSH2 key exchange
80: */
81:
1.32 markus 82: u_char *session_id2 = NULL;
1.120 markus 83: u_int session_id2_len = 0;
1.1 markus 84:
1.61 markus 85: char *xxx_host;
86: struct sockaddr *xxx_hostaddr;
87:
1.63 markus 88: Kex *xxx_kex = NULL;
89:
1.76 itojun 90: static int
1.75 markus 91: verify_host_key_callback(Key *hostkey)
1.61 markus 92: {
1.75 markus 93: if (verify_host_key(xxx_host, xxx_hostaddr, hostkey) == -1)
1.83 markus 94: fatal("Host key verification failed.");
1.61 markus 95: return 0;
96: }
97:
1.1 markus 98: void
1.22 provos 99: ssh_kex2(char *host, struct sockaddr *hostaddr)
100: {
101: Kex *kex;
1.61 markus 102:
103: xxx_host = host;
104: xxx_hostaddr = hostaddr;
1.22 provos 105:
1.29 markus 106: if (options.ciphers == (char *)-1) {
1.116 itojun 107: logit("No valid ciphers for protocol version 2 given, using defaults.");
1.29 markus 108: options.ciphers = NULL;
1.24 markus 109: }
1.22 provos 110: if (options.ciphers != NULL) {
111: myproposal[PROPOSAL_ENC_ALGS_CTOS] =
112: myproposal[PROPOSAL_ENC_ALGS_STOC] = options.ciphers;
113: }
1.60 stevesk 114: myproposal[PROPOSAL_ENC_ALGS_CTOS] =
115: compat_cipher_proposal(myproposal[PROPOSAL_ENC_ALGS_CTOS]);
116: myproposal[PROPOSAL_ENC_ALGS_STOC] =
117: compat_cipher_proposal(myproposal[PROPOSAL_ENC_ALGS_STOC]);
1.22 provos 118: if (options.compression) {
1.47 markus 119: myproposal[PROPOSAL_COMP_ALGS_CTOS] =
1.141 markus 120: myproposal[PROPOSAL_COMP_ALGS_STOC] = "zlib@openssh.com,zlib,none";
1.22 provos 121: } else {
1.47 markus 122: myproposal[PROPOSAL_COMP_ALGS_CTOS] =
1.141 markus 123: myproposal[PROPOSAL_COMP_ALGS_STOC] = "none,zlib@openssh.com,zlib";
1.47 markus 124: }
125: if (options.macs != NULL) {
126: myproposal[PROPOSAL_MAC_ALGS_CTOS] =
127: myproposal[PROPOSAL_MAC_ALGS_STOC] = options.macs;
1.22 provos 128: }
1.70 markus 129: if (options.hostkeyalgorithms != NULL)
1.88 deraadt 130: myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] =
1.70 markus 131: options.hostkeyalgorithms;
1.115 markus 132:
133: if (options.rekey_limit)
1.165 djm 134: packet_set_rekey_limit((u_int32_t)options.rekey_limit);
1.22 provos 135:
1.65 markus 136: /* start key exchange */
1.64 markus 137: kex = kex_setup(myproposal);
1.111 markus 138: kex->kex[KEX_DH_GRP1_SHA1] = kexdh_client;
1.138 djm 139: kex->kex[KEX_DH_GRP14_SHA1] = kexdh_client;
1.111 markus 140: kex->kex[KEX_DH_GEX_SHA1] = kexgex_client;
1.147 djm 141: kex->kex[KEX_DH_GEX_SHA256] = kexgex_client;
1.61 markus 142: kex->client_version_string=client_version_string;
143: kex->server_version_string=server_version_string;
1.75 markus 144: kex->verify_host_key=&verify_host_key_callback;
1.63 markus 145:
146: xxx_kex = kex;
1.22 provos 147:
1.66 markus 148: dispatch_run(DISPATCH_BLOCK, &kex->done, kex);
1.173 andreas 149:
150: if (options.use_roaming && !kex->roaming) {
151: debug("Roaming not allowed by server");
152: options.use_roaming = 0;
153: }
1.62 markus 154:
155: session_id2 = kex->session_id;
156: session_id2_len = kex->session_id_len;
1.22 provos 157:
158: #ifdef DEBUG_KEXDH
159: /* send 1st encrypted/maced/compressed message */
160: packet_start(SSH2_MSG_IGNORE);
161: packet_put_cstring("markus");
162: packet_send();
163: packet_write_wait();
164: #endif
1.1 markus 165: }
1.11 markus 166:
1.1 markus 167: /*
168: * Authenticate user
169: */
1.20 markus 170:
171: typedef struct Authctxt Authctxt;
172: typedef struct Authmethod Authmethod;
1.117 markus 173: typedef struct identity Identity;
174: typedef struct idlist Idlist;
1.20 markus 175:
1.117 markus 176: struct identity {
177: TAILQ_ENTRY(identity) next;
178: AuthenticationConnection *ac; /* set if agent supports key */
179: Key *key; /* public/private key */
180: char *filename; /* comment for agent-only keys */
181: int tried;
182: int isprivate; /* key points to the private key */
183: };
184: TAILQ_HEAD(idlist, identity);
1.20 markus 185:
186: struct Authctxt {
187: const char *server_user;
1.68 markus 188: const char *local_user;
1.20 markus 189: const char *host;
190: const char *service;
1.23 markus 191: Authmethod *method;
1.183 ! djm 192: sig_atomic_t success;
1.51 markus 193: char *authlist;
1.68 markus 194: /* pubkey */
1.117 markus 195: Idlist keys;
1.68 markus 196: AuthenticationConnection *agent;
197: /* hostbased */
1.100 markus 198: Sensitive *sensitive;
1.82 markus 199: /* kbd-interactive */
200: int info_req_seen;
1.121 markus 201: /* generic */
202: void *methoddata;
1.20 markus 203: };
204: struct Authmethod {
205: char *name; /* string to compare against server's list */
206: int (*userauth)(Authctxt *authctxt);
1.170 djm 207: void (*cleanup)(Authctxt *authctxt);
1.20 markus 208: int *enabled; /* flag in option struct that enables method */
209: int *batch_flag; /* flag in option struct that disables method */
210: };
211:
1.92 markus 212: void input_userauth_success(int, u_int32_t, void *);
1.172 djm 213: void input_userauth_success_unexpected(int, u_int32_t, void *);
1.92 markus 214: void input_userauth_failure(int, u_int32_t, void *);
215: void input_userauth_banner(int, u_int32_t, void *);
216: void input_userauth_error(int, u_int32_t, void *);
217: void input_userauth_info_req(int, u_int32_t, void *);
218: void input_userauth_pk_ok(int, u_int32_t, void *);
1.99 markus 219: void input_userauth_passwd_changereq(int, u_int32_t, void *);
1.170 djm 220: void input_userauth_jpake_server_step1(int, u_int32_t, void *);
221: void input_userauth_jpake_server_step2(int, u_int32_t, void *);
222: void input_userauth_jpake_server_confirm(int, u_int32_t, void *);
1.86 itojun 223:
224: int userauth_none(Authctxt *);
225: int userauth_pubkey(Authctxt *);
226: int userauth_passwd(Authctxt *);
227: int userauth_kbdint(Authctxt *);
228: int userauth_hostbased(Authctxt *);
1.170 djm 229: int userauth_jpake(Authctxt *);
230:
231: void userauth_jpake_cleanup(Authctxt *);
1.20 markus 232:
1.121 markus 233: #ifdef GSSAPI
234: int userauth_gssapi(Authctxt *authctxt);
235: void input_gssapi_response(int type, u_int32_t, void *);
236: void input_gssapi_token(int type, u_int32_t, void *);
237: void input_gssapi_hash(int type, u_int32_t, void *);
238: void input_gssapi_error(int, u_int32_t, void *);
239: void input_gssapi_errtok(int, u_int32_t, void *);
240: #endif
241:
1.86 itojun 242: void userauth(Authctxt *, char *);
1.51 markus 243:
1.117 markus 244: static int sign_and_send_pubkey(Authctxt *, Identity *);
245: static void pubkey_prepare(Authctxt *);
246: static void pubkey_cleanup(Authctxt *);
247: static Key *load_identity_file(char *);
1.76 itojun 248:
249: static Authmethod *authmethod_get(char *authlist);
250: static Authmethod *authmethod_lookup(const char *name);
251: static char *authmethods_get(void);
1.20 markus 252:
253: Authmethod authmethods[] = {
1.121 markus 254: #ifdef GSSAPI
1.132 markus 255: {"gssapi-with-mic",
1.121 markus 256: userauth_gssapi,
1.170 djm 257: NULL,
1.121 markus 258: &options.gss_authentication,
259: NULL},
260: #endif
1.81 markus 261: {"hostbased",
262: userauth_hostbased,
1.170 djm 263: NULL,
1.81 markus 264: &options.hostbased_authentication,
265: NULL},
1.20 markus 266: {"publickey",
267: userauth_pubkey,
1.170 djm 268: NULL,
1.28 markus 269: &options.pubkey_authentication,
1.20 markus 270: NULL},
1.170 djm 271: #ifdef JPAKE
272: {"jpake-01@openssh.com",
273: userauth_jpake,
274: userauth_jpake_cleanup,
275: &options.zero_knowledge_password_authentication,
276: &options.batch_mode},
277: #endif
1.81 markus 278: {"keyboard-interactive",
279: userauth_kbdint,
1.170 djm 280: NULL,
1.81 markus 281: &options.kbd_interactive_authentication,
282: &options.batch_mode},
1.20 markus 283: {"password",
284: userauth_passwd,
1.170 djm 285: NULL,
1.20 markus 286: &options.password_authentication,
1.23 markus 287: &options.batch_mode},
288: {"none",
289: userauth_none,
290: NULL,
1.170 djm 291: NULL,
1.23 markus 292: NULL},
1.170 djm 293: {NULL, NULL, NULL, NULL, NULL}
1.20 markus 294: };
295:
296: void
1.68 markus 297: ssh_userauth2(const char *local_user, const char *server_user, char *host,
1.100 markus 298: Sensitive *sensitive)
1.20 markus 299: {
300: Authctxt authctxt;
301: int type;
1.39 markus 302:
1.73 markus 303: if (options.challenge_response_authentication)
1.39 markus 304: options.kbd_interactive_authentication = 1;
1.20 markus 305:
306: packet_start(SSH2_MSG_SERVICE_REQUEST);
307: packet_put_cstring("ssh-userauth");
308: packet_send();
1.108 markus 309: debug("SSH2_MSG_SERVICE_REQUEST sent");
1.20 markus 310: packet_write_wait();
1.91 markus 311: type = packet_read();
1.108 markus 312: if (type != SSH2_MSG_SERVICE_ACCEPT)
313: fatal("Server denied authentication request: %d", type);
1.20 markus 314: if (packet_remaining() > 0) {
1.91 markus 315: char *reply = packet_get_string(NULL);
1.108 markus 316: debug2("service_accept: %s", reply);
1.20 markus 317: xfree(reply);
318: } else {
1.109 markus 319: debug2("buggy server: service_accept w/o service");
1.20 markus 320: }
1.90 markus 321: packet_check_eom();
1.108 markus 322: debug("SSH2_MSG_SERVICE_ACCEPT received");
1.20 markus 323:
1.53 markus 324: if (options.preferred_authentications == NULL)
325: options.preferred_authentications = authmethods_get();
326:
1.20 markus 327: /* setup authentication context */
1.82 markus 328: memset(&authctxt, 0, sizeof(authctxt));
1.117 markus 329: pubkey_prepare(&authctxt);
1.20 markus 330: authctxt.server_user = server_user;
1.68 markus 331: authctxt.local_user = local_user;
1.20 markus 332: authctxt.host = host;
333: authctxt.service = "ssh-connection"; /* service name */
334: authctxt.success = 0;
1.23 markus 335: authctxt.method = authmethod_lookup("none");
1.51 markus 336: authctxt.authlist = NULL;
1.121 markus 337: authctxt.methoddata = NULL;
1.100 markus 338: authctxt.sensitive = sensitive;
1.82 markus 339: authctxt.info_req_seen = 0;
1.23 markus 340: if (authctxt.method == NULL)
341: fatal("ssh_userauth2: internal error: cannot send userauth none request");
1.20 markus 342:
343: /* initial userauth request */
1.23 markus 344: userauth_none(&authctxt);
1.20 markus 345:
1.65 markus 346: dispatch_init(&input_userauth_error);
1.20 markus 347: dispatch_set(SSH2_MSG_USERAUTH_SUCCESS, &input_userauth_success);
348: dispatch_set(SSH2_MSG_USERAUTH_FAILURE, &input_userauth_failure);
1.35 markus 349: dispatch_set(SSH2_MSG_USERAUTH_BANNER, &input_userauth_banner);
1.20 markus 350: dispatch_run(DISPATCH_BLOCK, &authctxt.success, &authctxt); /* loop until success */
351:
1.117 markus 352: pubkey_cleanup(&authctxt);
1.119 markus 353: dispatch_range(SSH2_MSG_USERAUTH_MIN, SSH2_MSG_USERAUTH_MAX, NULL);
354:
1.109 markus 355: debug("Authentication succeeded (%s).", authctxt.method->name);
1.20 markus 356: }
1.119 markus 357:
1.20 markus 358: void
1.51 markus 359: userauth(Authctxt *authctxt, char *authlist)
360: {
1.170 djm 361: if (authctxt->method != NULL && authctxt->method->cleanup != NULL)
362: authctxt->method->cleanup(authctxt);
363:
1.121 markus 364: if (authctxt->methoddata) {
365: xfree(authctxt->methoddata);
366: authctxt->methoddata = NULL;
367: }
1.51 markus 368: if (authlist == NULL) {
369: authlist = authctxt->authlist;
370: } else {
371: if (authctxt->authlist)
372: xfree(authctxt->authlist);
373: authctxt->authlist = authlist;
374: }
375: for (;;) {
376: Authmethod *method = authmethod_get(authlist);
377: if (method == NULL)
378: fatal("Permission denied (%s).", authlist);
379: authctxt->method = method;
1.119 markus 380:
381: /* reset the per method handler */
382: dispatch_range(SSH2_MSG_USERAUTH_PER_METHOD_MIN,
383: SSH2_MSG_USERAUTH_PER_METHOD_MAX, NULL);
384:
385: /* and try new method */
1.51 markus 386: if (method->userauth(authctxt) != 0) {
387: debug2("we sent a %s packet, wait for reply", method->name);
388: break;
389: } else {
390: debug2("we did not send a packet, disable method");
391: method->enabled = NULL;
392: }
393: }
394: }
1.105 deraadt 395:
1.169 djm 396: /* ARGSUSED */
1.51 markus 397: void
1.92 markus 398: input_userauth_error(int type, u_int32_t seq, void *ctxt)
1.20 markus 399: {
1.35 markus 400: fatal("input_userauth_error: bad message during authentication: "
1.140 djm 401: "type %d", type);
1.35 markus 402: }
1.105 deraadt 403:
1.169 djm 404: /* ARGSUSED */
1.35 markus 405: void
1.92 markus 406: input_userauth_banner(int type, u_int32_t seq, void *ctxt)
1.35 markus 407: {
1.166 djm 408: char *msg, *raw, *lang;
409: u_int len;
1.126 deraadt 410:
1.35 markus 411: debug3("input_userauth_banner");
1.166 djm 412: raw = packet_get_string(&len);
1.35 markus 413: lang = packet_get_string(NULL);
1.167 markus 414: if (len > 0 && options.log_level >= SYSLOG_LEVEL_INFO) {
1.166 djm 415: if (len > 65536)
416: len = 65536;
1.168 deraadt 417: msg = xmalloc(len * 4 + 1); /* max expansion from strnvis() */
1.177 dtucker 418: strnvis(msg, raw, len * 4 + 1, VIS_SAFE|VIS_OCTAL|VIS_NOSLASH);
1.125 dtucker 419: fprintf(stderr, "%s", msg);
1.166 djm 420: xfree(msg);
421: }
422: xfree(raw);
1.35 markus 423: xfree(lang);
1.20 markus 424: }
1.105 deraadt 425:
1.169 djm 426: /* ARGSUSED */
1.20 markus 427: void
1.92 markus 428: input_userauth_success(int type, u_int32_t seq, void *ctxt)
1.20 markus 429: {
430: Authctxt *authctxt = ctxt;
1.172 djm 431:
1.20 markus 432: if (authctxt == NULL)
433: fatal("input_userauth_success: no authentication context");
1.126 deraadt 434: if (authctxt->authlist) {
1.51 markus 435: xfree(authctxt->authlist);
1.126 deraadt 436: authctxt->authlist = NULL;
437: }
1.172 djm 438: if (authctxt->method != NULL && authctxt->method->cleanup != NULL)
439: authctxt->method->cleanup(authctxt);
1.126 deraadt 440: if (authctxt->methoddata) {
1.121 markus 441: xfree(authctxt->methoddata);
1.126 deraadt 442: authctxt->methoddata = NULL;
443: }
1.20 markus 444: authctxt->success = 1; /* break out */
445: }
1.105 deraadt 446:
1.172 djm 447: void
448: input_userauth_success_unexpected(int type, u_int32_t seq, void *ctxt)
449: {
450: Authctxt *authctxt = ctxt;
451:
452: if (authctxt == NULL)
453: fatal("%s: no authentication context", __func__);
454:
455: fatal("Unexpected authentication success during %s.",
456: authctxt->method->name);
457: }
458:
1.169 djm 459: /* ARGSUSED */
1.20 markus 460: void
1.92 markus 461: input_userauth_failure(int type, u_int32_t seq, void *ctxt)
1.20 markus 462: {
463: Authctxt *authctxt = ctxt;
464: char *authlist = NULL;
465: int partial;
466:
467: if (authctxt == NULL)
468: fatal("input_userauth_failure: no authentication context");
469:
1.23 markus 470: authlist = packet_get_string(NULL);
1.20 markus 471: partial = packet_get_char();
1.90 markus 472: packet_check_eom();
1.20 markus 473:
474: if (partial != 0)
1.116 itojun 475: logit("Authenticated with partial success.");
1.109 markus 476: debug("Authentications that can continue: %s", authlist);
1.20 markus 477:
1.51 markus 478: userauth(authctxt, authlist);
479: }
1.169 djm 480:
481: /* ARGSUSED */
1.51 markus 482: void
1.92 markus 483: input_userauth_pk_ok(int type, u_int32_t seq, void *ctxt)
1.51 markus 484: {
485: Authctxt *authctxt = ctxt;
486: Key *key = NULL;
1.117 markus 487: Identity *id = NULL;
1.51 markus 488: Buffer b;
1.96 markus 489: int pktype, sent = 0;
490: u_int alen, blen;
491: char *pkalg, *fp;
492: u_char *pkblob;
1.51 markus 493:
494: if (authctxt == NULL)
495: fatal("input_userauth_pk_ok: no authentication context");
496: if (datafellows & SSH_BUG_PKOK) {
497: /* this is similar to SSH_BUG_PKAUTH */
498: debug2("input_userauth_pk_ok: SSH_BUG_PKOK");
499: pkblob = packet_get_string(&blen);
500: buffer_init(&b);
501: buffer_append(&b, pkblob, blen);
502: pkalg = buffer_get_string(&b, &alen);
503: buffer_free(&b);
504: } else {
505: pkalg = packet_get_string(&alen);
506: pkblob = packet_get_string(&blen);
507: }
1.90 markus 508: packet_check_eom();
1.51 markus 509:
1.117 markus 510: debug("Server accepts key: pkalg %s blen %u", pkalg, blen);
1.51 markus 511:
1.117 markus 512: if ((pktype = key_type_from_name(pkalg)) == KEY_UNSPEC) {
513: debug("unknown pkalg %s", pkalg);
514: goto done;
515: }
516: if ((key = key_from_blob(pkblob, blen)) == NULL) {
517: debug("no key from blob. pkalg %s", pkalg);
518: goto done;
519: }
520: if (key->type != pktype) {
521: error("input_userauth_pk_ok: type mismatch "
522: "for decoded key (received %d, expected %d)",
523: key->type, pktype);
524: goto done;
525: }
526: fp = key_fingerprint(key, SSH_FP_MD5, SSH_FP_HEX);
527: debug2("input_userauth_pk_ok: fp %s", fp);
528: xfree(fp);
529:
1.127 markus 530: /*
531: * search keys in the reverse order, because last candidate has been
532: * moved to the end of the queue. this also avoids confusion by
533: * duplicate keys
534: */
1.136 henning 535: TAILQ_FOREACH_REVERSE(id, &authctxt->keys, idlist, next) {
1.117 markus 536: if (key_equal(key, id->key)) {
537: sent = sign_and_send_pubkey(authctxt, id);
1.51 markus 538: break;
539: }
1.117 markus 540: }
541: done:
1.51 markus 542: if (key != NULL)
543: key_free(key);
544: xfree(pkalg);
545: xfree(pkblob);
546:
1.106 deraadt 547: /* try another method if we did not send a packet */
1.51 markus 548: if (sent == 0)
549: userauth(authctxt, NULL);
1.20 markus 550: }
1.121 markus 551:
552: #ifdef GSSAPI
1.133 djm 553: int
1.121 markus 554: userauth_gssapi(Authctxt *authctxt)
555: {
556: Gssctxt *gssctxt = NULL;
1.128 avsm 557: static gss_OID_set gss_supported = NULL;
1.139 djm 558: static u_int mech = 0;
1.121 markus 559: OM_uint32 min;
560: int ok = 0;
561:
562: /* Try one GSSAPI method at a time, rather than sending them all at
563: * once. */
564:
1.128 avsm 565: if (gss_supported == NULL)
566: gss_indicate_mechs(&min, &gss_supported);
1.121 markus 567:
568: /* Check to see if the mechanism is usable before we offer it */
1.128 avsm 569: while (mech < gss_supported->count && !ok) {
1.121 markus 570: /* My DER encoding requires length<128 */
1.128 avsm 571: if (gss_supported->elements[mech].length < 128 &&
1.161 djm 572: ssh_gssapi_check_mechanism(&gssctxt,
573: &gss_supported->elements[mech], authctxt->host)) {
1.121 markus 574: ok = 1; /* Mechanism works */
575: } else {
576: mech++;
577: }
578: }
579:
1.161 djm 580: if (!ok)
1.139 djm 581: return 0;
1.121 markus 582:
583: authctxt->methoddata=(void *)gssctxt;
584:
585: packet_start(SSH2_MSG_USERAUTH_REQUEST);
586: packet_put_cstring(authctxt->server_user);
587: packet_put_cstring(authctxt->service);
588: packet_put_cstring(authctxt->method->name);
589:
590: packet_put_int(1);
591:
1.129 markus 592: packet_put_int((gss_supported->elements[mech].length) + 2);
593: packet_put_char(SSH_GSS_OIDTYPE);
594: packet_put_char(gss_supported->elements[mech].length);
595: packet_put_raw(gss_supported->elements[mech].elements,
596: gss_supported->elements[mech].length);
1.121 markus 597:
598: packet_send();
599:
600: dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_RESPONSE, &input_gssapi_response);
601: dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, &input_gssapi_token);
602: dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERROR, &input_gssapi_error);
603: dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK, &input_gssapi_errtok);
604:
605: mech++; /* Move along to next candidate */
606:
607: return 1;
608: }
609:
1.130 markus 610: static OM_uint32
611: process_gssapi_token(void *ctxt, gss_buffer_t recv_tok)
612: {
613: Authctxt *authctxt = ctxt;
614: Gssctxt *gssctxt = authctxt->methoddata;
615: gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
1.142 djm 616: gss_buffer_desc mic = GSS_C_EMPTY_BUFFER;
617: gss_buffer_desc gssbuf;
1.132 markus 618: OM_uint32 status, ms, flags;
619: Buffer b;
1.133 djm 620:
1.130 markus 621: status = ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
1.132 markus 622: recv_tok, &send_tok, &flags);
1.130 markus 623:
624: if (send_tok.length > 0) {
625: if (GSS_ERROR(status))
626: packet_start(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK);
627: else
628: packet_start(SSH2_MSG_USERAUTH_GSSAPI_TOKEN);
1.133 djm 629:
1.130 markus 630: packet_put_string(send_tok.value, send_tok.length);
631: packet_send();
632: gss_release_buffer(&ms, &send_tok);
633: }
1.133 djm 634:
1.130 markus 635: if (status == GSS_S_COMPLETE) {
1.132 markus 636: /* send either complete or MIC, depending on mechanism */
637: if (!(flags & GSS_C_INTEG_FLAG)) {
638: packet_start(SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE);
639: packet_send();
640: } else {
641: ssh_gssapi_buildmic(&b, authctxt->server_user,
642: authctxt->service, "gssapi-with-mic");
643:
644: gssbuf.value = buffer_ptr(&b);
645: gssbuf.length = buffer_len(&b);
1.133 djm 646:
1.132 markus 647: status = ssh_gssapi_sign(gssctxt, &gssbuf, &mic);
1.133 djm 648:
1.132 markus 649: if (!GSS_ERROR(status)) {
650: packet_start(SSH2_MSG_USERAUTH_GSSAPI_MIC);
651: packet_put_string(mic.value, mic.length);
1.133 djm 652:
1.132 markus 653: packet_send();
654: }
1.133 djm 655:
1.132 markus 656: buffer_free(&b);
657: gss_release_buffer(&ms, &mic);
1.133 djm 658: }
1.130 markus 659: }
1.133 djm 660:
1.130 markus 661: return status;
662: }
663:
1.169 djm 664: /* ARGSUSED */
1.121 markus 665: void
666: input_gssapi_response(int type, u_int32_t plen, void *ctxt)
667: {
668: Authctxt *authctxt = ctxt;
669: Gssctxt *gssctxt;
670: int oidlen;
671: char *oidv;
672:
673: if (authctxt == NULL)
674: fatal("input_gssapi_response: no authentication context");
675: gssctxt = authctxt->methoddata;
676:
677: /* Setup our OID */
678: oidv = packet_get_string(&oidlen);
679:
1.129 markus 680: if (oidlen <= 2 ||
681: oidv[0] != SSH_GSS_OIDTYPE ||
682: oidv[1] != oidlen - 2) {
1.130 markus 683: xfree(oidv);
1.129 markus 684: debug("Badly encoded mechanism OID received");
685: userauth(authctxt, NULL);
686: return;
1.121 markus 687: }
1.129 markus 688:
689: if (!ssh_gssapi_check_oid(gssctxt, oidv + 2, oidlen - 2))
690: fatal("Server returned different OID than expected");
1.121 markus 691:
692: packet_check_eom();
693:
694: xfree(oidv);
695:
1.130 markus 696: if (GSS_ERROR(process_gssapi_token(ctxt, GSS_C_NO_BUFFER))) {
1.121 markus 697: /* Start again with next method on list */
698: debug("Trying to start again");
699: userauth(authctxt, NULL);
700: return;
701: }
702: }
703:
1.169 djm 704: /* ARGSUSED */
1.121 markus 705: void
706: input_gssapi_token(int type, u_int32_t plen, void *ctxt)
707: {
708: Authctxt *authctxt = ctxt;
709: gss_buffer_desc recv_tok;
1.130 markus 710: OM_uint32 status;
1.121 markus 711: u_int slen;
712:
713: if (authctxt == NULL)
714: fatal("input_gssapi_response: no authentication context");
715:
716: recv_tok.value = packet_get_string(&slen);
717: recv_tok.length = slen; /* safe typecast */
718:
719: packet_check_eom();
720:
1.130 markus 721: status = process_gssapi_token(ctxt, &recv_tok);
1.121 markus 722:
723: xfree(recv_tok.value);
724:
725: if (GSS_ERROR(status)) {
726: /* Start again with the next method in the list */
727: userauth(authctxt, NULL);
728: return;
729: }
730: }
731:
1.169 djm 732: /* ARGSUSED */
1.121 markus 733: void
734: input_gssapi_errtok(int type, u_int32_t plen, void *ctxt)
735: {
736: Authctxt *authctxt = ctxt;
737: Gssctxt *gssctxt;
738: gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
739: gss_buffer_desc recv_tok;
740: OM_uint32 status, ms;
1.123 deraadt 741: u_int len;
1.121 markus 742:
743: if (authctxt == NULL)
744: fatal("input_gssapi_response: no authentication context");
745: gssctxt = authctxt->methoddata;
746:
1.123 deraadt 747: recv_tok.value = packet_get_string(&len);
748: recv_tok.length = len;
1.121 markus 749:
750: packet_check_eom();
751:
752: /* Stick it into GSSAPI and see what it says */
753: status = ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
1.140 djm 754: &recv_tok, &send_tok, NULL);
1.121 markus 755:
756: xfree(recv_tok.value);
757: gss_release_buffer(&ms, &send_tok);
758:
759: /* Server will be returning a failed packet after this one */
760: }
761:
1.169 djm 762: /* ARGSUSED */
1.121 markus 763: void
764: input_gssapi_error(int type, u_int32_t plen, void *ctxt)
765: {
766: OM_uint32 maj, min;
767: char *msg;
768: char *lang;
769:
770: maj=packet_get_int();
771: min=packet_get_int();
772: msg=packet_get_string(NULL);
773: lang=packet_get_string(NULL);
774:
775: packet_check_eom();
776:
1.143 stevesk 777: debug("Server GSSAPI Error:\n%s", msg);
1.121 markus 778: xfree(msg);
779: xfree(lang);
780: }
781: #endif /* GSSAPI */
1.20 markus 782:
1.1 markus 783: int
1.23 markus 784: userauth_none(Authctxt *authctxt)
785: {
786: /* initial userauth request */
787: packet_start(SSH2_MSG_USERAUTH_REQUEST);
788: packet_put_cstring(authctxt->server_user);
789: packet_put_cstring(authctxt->service);
790: packet_put_cstring(authctxt->method->name);
791: packet_send();
792: return 1;
793: }
794:
795: int
1.20 markus 796: userauth_passwd(Authctxt *authctxt)
1.1 markus 797: {
1.6 markus 798: static int attempt = 0;
1.99 markus 799: char prompt[150];
1.1 markus 800: char *password;
1.175 dtucker 801: const char *host = options.host_key_alias ? options.host_key_alias :
802: authctxt->host;
1.6 markus 803:
1.13 todd 804: if (attempt++ >= options.number_of_password_prompts)
1.6 markus 805: return 0;
1.13 todd 806:
1.87 deraadt 807: if (attempt != 1)
1.13 todd 808: error("Permission denied, please try again.");
1.1 markus 809:
1.43 itojun 810: snprintf(prompt, sizeof(prompt), "%.30s@%.128s's password: ",
1.175 dtucker 811: authctxt->server_user, host);
1.1 markus 812: password = read_passphrase(prompt, 0);
813: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1.20 markus 814: packet_put_cstring(authctxt->server_user);
815: packet_put_cstring(authctxt->service);
1.23 markus 816: packet_put_cstring(authctxt->method->name);
1.1 markus 817: packet_put_char(0);
1.49 markus 818: packet_put_cstring(password);
1.1 markus 819: memset(password, 0, strlen(password));
820: xfree(password);
1.85 markus 821: packet_add_padding(64);
1.1 markus 822: packet_send();
1.99 markus 823:
1.104 deraadt 824: dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
1.99 markus 825: &input_userauth_passwd_changereq);
826:
1.1 markus 827: return 1;
828: }
1.169 djm 829:
1.99 markus 830: /*
831: * parse PASSWD_CHANGEREQ, prompt user and send SSH2_MSG_USERAUTH_REQUEST
832: */
1.169 djm 833: /* ARGSUSED */
1.99 markus 834: void
1.153 djm 835: input_userauth_passwd_changereq(int type, u_int32_t seqnr, void *ctxt)
1.99 markus 836: {
837: Authctxt *authctxt = ctxt;
838: char *info, *lang, *password = NULL, *retype = NULL;
839: char prompt[150];
1.175 dtucker 840: const char *host = options.host_key_alias ? options.host_key_alias :
841: authctxt->host;
1.99 markus 842:
843: debug2("input_userauth_passwd_changereq");
844:
845: if (authctxt == NULL)
846: fatal("input_userauth_passwd_changereq: "
847: "no authentication context");
848:
849: info = packet_get_string(NULL);
850: lang = packet_get_string(NULL);
851: if (strlen(info) > 0)
1.116 itojun 852: logit("%s", info);
1.99 markus 853: xfree(info);
854: xfree(lang);
855: packet_start(SSH2_MSG_USERAUTH_REQUEST);
856: packet_put_cstring(authctxt->server_user);
857: packet_put_cstring(authctxt->service);
858: packet_put_cstring(authctxt->method->name);
859: packet_put_char(1); /* additional info */
1.104 deraadt 860: snprintf(prompt, sizeof(prompt),
1.99 markus 861: "Enter %.30s@%.128s's old password: ",
1.175 dtucker 862: authctxt->server_user, host);
1.99 markus 863: password = read_passphrase(prompt, 0);
864: packet_put_cstring(password);
865: memset(password, 0, strlen(password));
866: xfree(password);
867: password = NULL;
868: while (password == NULL) {
1.104 deraadt 869: snprintf(prompt, sizeof(prompt),
1.99 markus 870: "Enter %.30s@%.128s's new password: ",
1.175 dtucker 871: authctxt->server_user, host);
1.99 markus 872: password = read_passphrase(prompt, RP_ALLOW_EOF);
873: if (password == NULL) {
874: /* bail out */
875: return;
876: }
1.104 deraadt 877: snprintf(prompt, sizeof(prompt),
1.99 markus 878: "Retype %.30s@%.128s's new password: ",
1.175 dtucker 879: authctxt->server_user, host);
1.99 markus 880: retype = read_passphrase(prompt, 0);
881: if (strcmp(password, retype) != 0) {
882: memset(password, 0, strlen(password));
883: xfree(password);
1.116 itojun 884: logit("Mismatch; try again, EOF to quit.");
1.99 markus 885: password = NULL;
886: }
887: memset(retype, 0, strlen(retype));
888: xfree(retype);
889: }
890: packet_put_cstring(password);
891: memset(password, 0, strlen(password));
892: xfree(password);
893: packet_add_padding(64);
894: packet_send();
1.104 deraadt 895:
896: dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
1.99 markus 897: &input_userauth_passwd_changereq);
1.117 markus 898: }
899:
1.170 djm 900: #ifdef JPAKE
901: static char *
902: pw_encrypt(const char *password, const char *crypt_scheme, const char *salt)
903: {
904: /* OpenBSD crypt(3) handles all of these */
905: if (strcmp(crypt_scheme, "crypt") == 0 ||
906: strcmp(crypt_scheme, "bcrypt") == 0 ||
907: strcmp(crypt_scheme, "md5crypt") == 0 ||
908: strcmp(crypt_scheme, "crypt-extended") == 0)
909: return xstrdup(crypt(password, salt));
910: error("%s: unsupported password encryption scheme \"%.100s\"",
911: __func__, crypt_scheme);
912: return NULL;
913: }
914:
915: static BIGNUM *
916: jpake_password_to_secret(Authctxt *authctxt, const char *crypt_scheme,
917: const char *salt)
918: {
919: char prompt[256], *password, *crypted;
920: u_char *secret;
921: u_int secret_len;
922: BIGNUM *ret;
923:
924: snprintf(prompt, sizeof(prompt), "%.30s@%.128s's password (JPAKE): ",
925: authctxt->server_user, authctxt->host);
926: password = read_passphrase(prompt, 0);
927:
928: if ((crypted = pw_encrypt(password, crypt_scheme, salt)) == NULL) {
929: logit("Disabling %s authentication", authctxt->method->name);
930: authctxt->method->enabled = NULL;
931: /* Continue with an empty password to fail gracefully */
932: crypted = xstrdup("");
933: }
934:
935: #ifdef JPAKE_DEBUG
936: debug3("%s: salt = %s", __func__, salt);
937: debug3("%s: scheme = %s", __func__, crypt_scheme);
938: debug3("%s: crypted = %s", __func__, crypted);
939: #endif
940:
941: if (hash_buffer(crypted, strlen(crypted), EVP_sha256(),
942: &secret, &secret_len) != 0)
943: fatal("%s: hash_buffer", __func__);
944:
945: bzero(password, strlen(password));
946: bzero(crypted, strlen(crypted));
947: xfree(password);
948: xfree(crypted);
949:
950: if ((ret = BN_bin2bn(secret, secret_len, NULL)) == NULL)
951: fatal("%s: BN_bin2bn (secret)", __func__);
952: bzero(secret, secret_len);
953: xfree(secret);
954:
955: return ret;
956: }
957:
958: /* ARGSUSED */
959: void
960: input_userauth_jpake_server_step1(int type, u_int32_t seq, void *ctxt)
961: {
962: Authctxt *authctxt = ctxt;
963: struct jpake_ctx *pctx = authctxt->methoddata;
964: u_char *x3_proof, *x4_proof, *x2_s_proof;
965: u_int x3_proof_len, x4_proof_len, x2_s_proof_len;
966: char *crypt_scheme, *salt;
967:
968: /* Disable this message */
969: dispatch_set(SSH2_MSG_USERAUTH_JPAKE_SERVER_STEP1, NULL);
970:
971: if ((pctx->g_x3 = BN_new()) == NULL ||
972: (pctx->g_x4 = BN_new()) == NULL)
973: fatal("%s: BN_new", __func__);
974:
975: /* Fetch step 1 values */
976: crypt_scheme = packet_get_string(NULL);
977: salt = packet_get_string(NULL);
978: pctx->server_id = packet_get_string(&pctx->server_id_len);
979: packet_get_bignum2(pctx->g_x3);
980: packet_get_bignum2(pctx->g_x4);
981: x3_proof = packet_get_string(&x3_proof_len);
982: x4_proof = packet_get_string(&x4_proof_len);
983: packet_check_eom();
984:
985: JPAKE_DEBUG_CTX((pctx, "step 1 received in %s", __func__));
986:
987: /* Obtain password and derive secret */
988: pctx->s = jpake_password_to_secret(authctxt, crypt_scheme, salt);
989: bzero(crypt_scheme, strlen(crypt_scheme));
990: bzero(salt, strlen(salt));
991: xfree(crypt_scheme);
992: xfree(salt);
993: JPAKE_DEBUG_BN((pctx->s, "%s: s = ", __func__));
994:
995: /* Calculate step 2 values */
996: jpake_step2(pctx->grp, pctx->s, pctx->g_x1,
997: pctx->g_x3, pctx->g_x4, pctx->x2,
998: pctx->server_id, pctx->server_id_len,
999: pctx->client_id, pctx->client_id_len,
1000: x3_proof, x3_proof_len,
1001: x4_proof, x4_proof_len,
1002: &pctx->a,
1003: &x2_s_proof, &x2_s_proof_len);
1004:
1005: bzero(x3_proof, x3_proof_len);
1006: bzero(x4_proof, x4_proof_len);
1007: xfree(x3_proof);
1008: xfree(x4_proof);
1009:
1010: JPAKE_DEBUG_CTX((pctx, "step 2 sending in %s", __func__));
1011:
1012: /* Send values for step 2 */
1013: packet_start(SSH2_MSG_USERAUTH_JPAKE_CLIENT_STEP2);
1014: packet_put_bignum2(pctx->a);
1015: packet_put_string(x2_s_proof, x2_s_proof_len);
1016: packet_send();
1017:
1018: bzero(x2_s_proof, x2_s_proof_len);
1019: xfree(x2_s_proof);
1020:
1021: /* Expect step 2 packet from peer */
1022: dispatch_set(SSH2_MSG_USERAUTH_JPAKE_SERVER_STEP2,
1023: input_userauth_jpake_server_step2);
1024: }
1025:
1026: /* ARGSUSED */
1027: void
1028: input_userauth_jpake_server_step2(int type, u_int32_t seq, void *ctxt)
1029: {
1030: Authctxt *authctxt = ctxt;
1031: struct jpake_ctx *pctx = authctxt->methoddata;
1032: u_char *x4_s_proof;
1033: u_int x4_s_proof_len;
1034:
1035: /* Disable this message */
1036: dispatch_set(SSH2_MSG_USERAUTH_JPAKE_SERVER_STEP2, NULL);
1037:
1038: if ((pctx->b = BN_new()) == NULL)
1039: fatal("%s: BN_new", __func__);
1040:
1041: /* Fetch step 2 values */
1042: packet_get_bignum2(pctx->b);
1043: x4_s_proof = packet_get_string(&x4_s_proof_len);
1044: packet_check_eom();
1045:
1046: JPAKE_DEBUG_CTX((pctx, "step 2 received in %s", __func__));
1047:
1048: /* Derive shared key and calculate confirmation hash */
1049: jpake_key_confirm(pctx->grp, pctx->s, pctx->b,
1050: pctx->x2, pctx->g_x1, pctx->g_x2, pctx->g_x3, pctx->g_x4,
1051: pctx->client_id, pctx->client_id_len,
1052: pctx->server_id, pctx->server_id_len,
1053: session_id2, session_id2_len,
1054: x4_s_proof, x4_s_proof_len,
1055: &pctx->k,
1056: &pctx->h_k_cid_sessid, &pctx->h_k_cid_sessid_len);
1057:
1058: bzero(x4_s_proof, x4_s_proof_len);
1059: xfree(x4_s_proof);
1060:
1061: JPAKE_DEBUG_CTX((pctx, "confirm sending in %s", __func__));
1062:
1063: /* Send key confirmation proof */
1064: packet_start(SSH2_MSG_USERAUTH_JPAKE_CLIENT_CONFIRM);
1065: packet_put_string(pctx->h_k_cid_sessid, pctx->h_k_cid_sessid_len);
1066: packet_send();
1067:
1068: /* Expect confirmation from peer */
1069: dispatch_set(SSH2_MSG_USERAUTH_JPAKE_SERVER_CONFIRM,
1070: input_userauth_jpake_server_confirm);
1071: }
1072:
1073: /* ARGSUSED */
1074: void
1075: input_userauth_jpake_server_confirm(int type, u_int32_t seq, void *ctxt)
1076: {
1077: Authctxt *authctxt = ctxt;
1078: struct jpake_ctx *pctx = authctxt->methoddata;
1079:
1080: /* Disable this message */
1081: dispatch_set(SSH2_MSG_USERAUTH_JPAKE_SERVER_CONFIRM, NULL);
1082:
1083: pctx->h_k_sid_sessid = packet_get_string(&pctx->h_k_sid_sessid_len);
1084: packet_check_eom();
1085:
1086: JPAKE_DEBUG_CTX((pctx, "confirm received in %s", __func__));
1087:
1088: /* Verify expected confirmation hash */
1089: if (jpake_check_confirm(pctx->k,
1090: pctx->server_id, pctx->server_id_len,
1091: session_id2, session_id2_len,
1092: pctx->h_k_sid_sessid, pctx->h_k_sid_sessid_len) == 1)
1093: debug("%s: %s success", __func__, authctxt->method->name);
1094: else {
1095: debug("%s: confirmation mismatch", __func__);
1096: /* XXX stash this so if auth succeeds then we can warn/kill */
1097: }
1098:
1099: userauth_jpake_cleanup(authctxt);
1100: }
1101: #endif /* JPAKE */
1102:
1.117 markus 1103: static int
1104: identity_sign(Identity *id, u_char **sigp, u_int *lenp,
1105: u_char *data, u_int datalen)
1106: {
1107: Key *prv;
1108: int ret;
1.99 markus 1109:
1.117 markus 1110: /* the agent supports this key */
1111: if (id->ac)
1112: return (ssh_agent_sign(id->ac, id->key, sigp, lenp,
1113: data, datalen));
1114: /*
1115: * we have already loaded the private key or
1116: * the private key is stored in external hardware
1117: */
1118: if (id->isprivate || (id->key->flags & KEY_FLAG_EXT))
1119: return (key_sign(id->key, sigp, lenp, data, datalen));
1120: /* load the private key from the file */
1121: if ((prv = load_identity_file(id->filename)) == NULL)
1122: return (-1);
1123: ret = key_sign(prv, sigp, lenp, data, datalen);
1124: key_free(prv);
1125: return (ret);
1.51 markus 1126: }
1127:
1.76 itojun 1128: static int
1.117 markus 1129: sign_and_send_pubkey(Authctxt *authctxt, Identity *id)
1.1 markus 1130: {
1131: Buffer b;
1.32 markus 1132: u_char *blob, *signature;
1.96 markus 1133: u_int bloblen, slen;
1.120 markus 1134: u_int skip = 0;
1.17 markus 1135: int ret = -1;
1.23 markus 1136: int have_sig = 1;
1.182 djm 1137: char *fp;
1.1 markus 1138:
1.182 djm 1139: fp = key_fingerprint(id->key, SSH_FP_MD5, SSH_FP_HEX);
1140: debug3("sign_and_send_pubkey: %s %s", key_type(id->key), fp);
1141: xfree(fp);
1.51 markus 1142:
1.117 markus 1143: if (key_to_blob(id->key, &blob, &bloblen) == 0) {
1.28 markus 1144: /* we cannot handle this key */
1.30 markus 1145: debug3("sign_and_send_pubkey: cannot handle key");
1.28 markus 1146: return 0;
1147: }
1.1 markus 1148: /* data to be signed */
1149: buffer_init(&b);
1.26 markus 1150: if (datafellows & SSH_OLD_SESSIONID) {
1151: buffer_append(&b, session_id2, session_id2_len);
1.41 stevesk 1152: skip = session_id2_len;
1.26 markus 1153: } else {
1.14 markus 1154: buffer_put_string(&b, session_id2, session_id2_len);
1155: skip = buffer_len(&b);
1156: }
1.1 markus 1157: buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
1.20 markus 1158: buffer_put_cstring(&b, authctxt->server_user);
1.10 markus 1159: buffer_put_cstring(&b,
1.30 markus 1160: datafellows & SSH_BUG_PKSERVICE ?
1.10 markus 1161: "ssh-userauth" :
1.20 markus 1162: authctxt->service);
1.30 markus 1163: if (datafellows & SSH_BUG_PKAUTH) {
1164: buffer_put_char(&b, have_sig);
1165: } else {
1166: buffer_put_cstring(&b, authctxt->method->name);
1167: buffer_put_char(&b, have_sig);
1.117 markus 1168: buffer_put_cstring(&b, key_ssh_name(id->key));
1.30 markus 1169: }
1.1 markus 1170: buffer_put_string(&b, blob, bloblen);
1171:
1172: /* generate signature */
1.117 markus 1173: ret = identity_sign(id, &signature, &slen,
1.51 markus 1174: buffer_ptr(&b), buffer_len(&b));
1.17 markus 1175: if (ret == -1) {
1176: xfree(blob);
1177: buffer_free(&b);
1178: return 0;
1179: }
1.28 markus 1180: #ifdef DEBUG_PK
1.1 markus 1181: buffer_dump(&b);
1182: #endif
1.30 markus 1183: if (datafellows & SSH_BUG_PKSERVICE) {
1.10 markus 1184: buffer_clear(&b);
1185: buffer_append(&b, session_id2, session_id2_len);
1.51 markus 1186: skip = session_id2_len;
1.10 markus 1187: buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
1.20 markus 1188: buffer_put_cstring(&b, authctxt->server_user);
1189: buffer_put_cstring(&b, authctxt->service);
1.23 markus 1190: buffer_put_cstring(&b, authctxt->method->name);
1191: buffer_put_char(&b, have_sig);
1.30 markus 1192: if (!(datafellows & SSH_BUG_PKAUTH))
1.117 markus 1193: buffer_put_cstring(&b, key_ssh_name(id->key));
1.10 markus 1194: buffer_put_string(&b, blob, bloblen);
1195: }
1196: xfree(blob);
1.51 markus 1197:
1.1 markus 1198: /* append signature */
1199: buffer_put_string(&b, signature, slen);
1200: xfree(signature);
1201:
1202: /* skip session id and packet type */
1.14 markus 1203: if (buffer_len(&b) < skip + 1)
1.20 markus 1204: fatal("userauth_pubkey: internal error");
1.14 markus 1205: buffer_consume(&b, skip + 1);
1.1 markus 1206:
1207: /* put remaining data from buffer into packet */
1208: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1209: packet_put_raw(buffer_ptr(&b), buffer_len(&b));
1210: buffer_free(&b);
1211: packet_send();
1.17 markus 1212:
1213: return 1;
1.16 markus 1214: }
1215:
1.76 itojun 1216: static int
1.117 markus 1217: send_pubkey_test(Authctxt *authctxt, Identity *id)
1.20 markus 1218: {
1.51 markus 1219: u_char *blob;
1.97 markus 1220: u_int bloblen, have_sig = 0;
1.20 markus 1221:
1.51 markus 1222: debug3("send_pubkey_test");
1.16 markus 1223:
1.117 markus 1224: if (key_to_blob(id->key, &blob, &bloblen) == 0) {
1.51 markus 1225: /* we cannot handle this key */
1226: debug3("send_pubkey_test: cannot handle key");
1.16 markus 1227: return 0;
1228: }
1.51 markus 1229: /* register callback for USERAUTH_PK_OK message */
1230: dispatch_set(SSH2_MSG_USERAUTH_PK_OK, &input_userauth_pk_ok);
1231:
1232: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1233: packet_put_cstring(authctxt->server_user);
1234: packet_put_cstring(authctxt->service);
1235: packet_put_cstring(authctxt->method->name);
1236: packet_put_char(have_sig);
1237: if (!(datafellows & SSH_BUG_PKAUTH))
1.117 markus 1238: packet_put_cstring(key_ssh_name(id->key));
1.51 markus 1239: packet_put_string(blob, bloblen);
1240: xfree(blob);
1241: packet_send();
1242: return 1;
1243: }
1244:
1.76 itojun 1245: static Key *
1.51 markus 1246: load_identity_file(char *filename)
1247: {
1248: Key *private;
1249: char prompt[300], *passphrase;
1.178 dtucker 1250: int perm_ok = 0, quit, i;
1.52 markus 1251: struct stat st;
1.16 markus 1252:
1.52 markus 1253: if (stat(filename, &st) < 0) {
1254: debug3("no such identity: %s", filename);
1255: return NULL;
1256: }
1.152 dtucker 1257: private = key_load_private_type(KEY_UNSPEC, filename, "", NULL, &perm_ok);
1258: if (!perm_ok)
1259: return NULL;
1.56 markus 1260: if (private == NULL) {
1261: if (options.batch_mode)
1.51 markus 1262: return NULL;
1.16 markus 1263: snprintf(prompt, sizeof prompt,
1.88 deraadt 1264: "Enter passphrase for key '%.100s': ", filename);
1.20 markus 1265: for (i = 0; i < options.number_of_password_prompts; i++) {
1266: passphrase = read_passphrase(prompt, 0);
1267: if (strcmp(passphrase, "") != 0) {
1.152 dtucker 1268: private = key_load_private_type(KEY_UNSPEC,
1269: filename, passphrase, NULL, NULL);
1.51 markus 1270: quit = 0;
1.20 markus 1271: } else {
1272: debug2("no passphrase given, try next key");
1.51 markus 1273: quit = 1;
1.20 markus 1274: }
1275: memset(passphrase, 0, strlen(passphrase));
1276: xfree(passphrase);
1.56 markus 1277: if (private != NULL || quit)
1.20 markus 1278: break;
1279: debug2("bad passphrase given, try again...");
1.16 markus 1280: }
1281: }
1.51 markus 1282: return private;
1283: }
1284:
1.117 markus 1285: /*
1286: * try keys in the following order:
1287: * 1. agent keys that are found in the config file
1288: * 2. other agent keys
1289: * 3. keys that are only listed in the config file
1290: */
1291: static void
1292: pubkey_prepare(Authctxt *authctxt)
1.51 markus 1293: {
1.117 markus 1294: Identity *id;
1295: Idlist agent, files, *preferred;
1296: Key *key;
1297: AuthenticationConnection *ac;
1298: char *comment;
1299: int i, found;
1.51 markus 1300:
1.117 markus 1301: TAILQ_INIT(&agent); /* keys from the agent */
1302: TAILQ_INIT(&files); /* keys from the config file */
1303: preferred = &authctxt->keys;
1304: TAILQ_INIT(preferred); /* preferred order of keys */
1305:
1306: /* list of keys stored in the filesystem */
1307: for (i = 0; i < options.num_identity_files; i++) {
1308: key = options.identity_keys[i];
1309: if (key && key->type == KEY_RSA1)
1.180 djm 1310: continue;
1311: if (key && key->cert && key->cert->type != SSH2_CERT_TYPE_USER)
1.117 markus 1312: continue;
1313: options.identity_keys[i] = NULL;
1.150 djm 1314: id = xcalloc(1, sizeof(*id));
1.117 markus 1315: id->key = key;
1316: id->filename = xstrdup(options.identity_files[i]);
1317: TAILQ_INSERT_TAIL(&files, id, next);
1318: }
1319: /* list of keys supported by the agent */
1320: if ((ac = ssh_get_authentication_connection())) {
1321: for (key = ssh_get_first_identity(ac, &comment, 2);
1322: key != NULL;
1323: key = ssh_get_next_identity(ac, &comment, 2)) {
1324: found = 0;
1325: TAILQ_FOREACH(id, &files, next) {
1.133 djm 1326: /* agent keys from the config file are preferred */
1.117 markus 1327: if (key_equal(key, id->key)) {
1328: key_free(key);
1329: xfree(comment);
1330: TAILQ_REMOVE(&files, id, next);
1331: TAILQ_INSERT_TAIL(preferred, id, next);
1332: id->ac = ac;
1333: found = 1;
1334: break;
1335: }
1336: }
1.135 markus 1337: if (!found && !options.identities_only) {
1.150 djm 1338: id = xcalloc(1, sizeof(*id));
1.117 markus 1339: id->key = key;
1340: id->filename = comment;
1341: id->ac = ac;
1342: TAILQ_INSERT_TAIL(&agent, id, next);
1343: }
1344: }
1345: /* append remaining agent keys */
1346: for (id = TAILQ_FIRST(&agent); id; id = TAILQ_FIRST(&agent)) {
1347: TAILQ_REMOVE(&agent, id, next);
1348: TAILQ_INSERT_TAIL(preferred, id, next);
1349: }
1350: authctxt->agent = ac;
1351: }
1352: /* append remaining keys from the config file */
1353: for (id = TAILQ_FIRST(&files); id; id = TAILQ_FIRST(&files)) {
1354: TAILQ_REMOVE(&files, id, next);
1355: TAILQ_INSERT_TAIL(preferred, id, next);
1356: }
1357: TAILQ_FOREACH(id, preferred, next) {
1358: debug2("key: %s (%p)", id->filename, id->key);
1359: }
1.17 markus 1360: }
1361:
1.117 markus 1362: static void
1363: pubkey_cleanup(Authctxt *authctxt)
1.51 markus 1364: {
1.117 markus 1365: Identity *id;
1.51 markus 1366:
1.117 markus 1367: if (authctxt->agent != NULL)
1368: ssh_close_authentication_connection(authctxt->agent);
1369: for (id = TAILQ_FIRST(&authctxt->keys); id;
1370: id = TAILQ_FIRST(&authctxt->keys)) {
1371: TAILQ_REMOVE(&authctxt->keys, id, next);
1372: if (id->key)
1373: key_free(id->key);
1374: if (id->filename)
1375: xfree(id->filename);
1376: xfree(id);
1377: }
1.1 markus 1378: }
1379:
1.20 markus 1380: int
1381: userauth_pubkey(Authctxt *authctxt)
1382: {
1.117 markus 1383: Identity *id;
1.20 markus 1384: int sent = 0;
1385:
1.117 markus 1386: while ((id = TAILQ_FIRST(&authctxt->keys))) {
1387: if (id->tried++)
1388: return (0);
1.127 markus 1389: /* move key to the end of the queue */
1.117 markus 1390: TAILQ_REMOVE(&authctxt->keys, id, next);
1391: TAILQ_INSERT_TAIL(&authctxt->keys, id, next);
1392: /*
1393: * send a test message if we have the public key. for
1394: * encrypted keys we cannot do this and have to load the
1395: * private key instead
1396: */
1397: if (id->key && id->key->type != KEY_RSA1) {
1.181 djm 1398: debug("Offering %s public key: %s", key_type(id->key),
1399: id->filename);
1.117 markus 1400: sent = send_pubkey_test(authctxt, id);
1401: } else if (id->key == NULL) {
1402: debug("Trying private key: %s", id->filename);
1403: id->key = load_identity_file(id->filename);
1404: if (id->key != NULL) {
1405: id->isprivate = 1;
1406: sent = sign_and_send_pubkey(authctxt, id);
1407: key_free(id->key);
1408: id->key = NULL;
1.51 markus 1409: }
1410: }
1.117 markus 1411: if (sent)
1412: return (sent);
1.28 markus 1413: }
1.117 markus 1414: return (0);
1.20 markus 1415: }
1416:
1.23 markus 1417: /*
1418: * Send userauth request message specifying keyboard-interactive method.
1419: */
1420: int
1421: userauth_kbdint(Authctxt *authctxt)
1422: {
1423: static int attempt = 0;
1424:
1425: if (attempt++ >= options.number_of_password_prompts)
1426: return 0;
1.82 markus 1427: /* disable if no SSH2_MSG_USERAUTH_INFO_REQUEST has been seen */
1428: if (attempt > 1 && !authctxt->info_req_seen) {
1429: debug3("userauth_kbdint: disable: no info_req_seen");
1430: dispatch_set(SSH2_MSG_USERAUTH_INFO_REQUEST, NULL);
1431: return 0;
1432: }
1.23 markus 1433:
1434: debug2("userauth_kbdint");
1435: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1436: packet_put_cstring(authctxt->server_user);
1437: packet_put_cstring(authctxt->service);
1438: packet_put_cstring(authctxt->method->name);
1439: packet_put_cstring(""); /* lang */
1440: packet_put_cstring(options.kbd_interactive_devices ?
1441: options.kbd_interactive_devices : "");
1442: packet_send();
1443:
1444: dispatch_set(SSH2_MSG_USERAUTH_INFO_REQUEST, &input_userauth_info_req);
1445: return 1;
1446: }
1447:
1448: /*
1.46 markus 1449: * parse INFO_REQUEST, prompt user and send INFO_RESPONSE
1.23 markus 1450: */
1451: void
1.92 markus 1452: input_userauth_info_req(int type, u_int32_t seq, void *ctxt)
1.23 markus 1453: {
1454: Authctxt *authctxt = ctxt;
1.46 markus 1455: char *name, *inst, *lang, *prompt, *response;
1.32 markus 1456: u_int num_prompts, i;
1.23 markus 1457: int echo = 0;
1458:
1459: debug2("input_userauth_info_req");
1460:
1461: if (authctxt == NULL)
1462: fatal("input_userauth_info_req: no authentication context");
1.82 markus 1463:
1464: authctxt->info_req_seen = 1;
1.23 markus 1465:
1466: name = packet_get_string(NULL);
1467: inst = packet_get_string(NULL);
1468: lang = packet_get_string(NULL);
1469: if (strlen(name) > 0)
1.116 itojun 1470: logit("%s", name);
1.23 markus 1471: if (strlen(inst) > 0)
1.116 itojun 1472: logit("%s", inst);
1.46 markus 1473: xfree(name);
1.23 markus 1474: xfree(inst);
1.46 markus 1475: xfree(lang);
1.23 markus 1476:
1477: num_prompts = packet_get_int();
1478: /*
1479: * Begin to build info response packet based on prompts requested.
1480: * We commit to providing the correct number of responses, so if
1481: * further on we run into a problem that prevents this, we have to
1482: * be sure and clean this up and send a correct error response.
1483: */
1484: packet_start(SSH2_MSG_USERAUTH_INFO_RESPONSE);
1485: packet_put_int(num_prompts);
1486:
1.73 markus 1487: debug2("input_userauth_info_req: num_prompts %d", num_prompts);
1.23 markus 1488: for (i = 0; i < num_prompts; i++) {
1489: prompt = packet_get_string(NULL);
1490: echo = packet_get_char();
1491:
1.77 markus 1492: response = read_passphrase(prompt, echo ? RP_ECHO : 0);
1.23 markus 1493:
1.49 markus 1494: packet_put_cstring(response);
1.23 markus 1495: memset(response, 0, strlen(response));
1496: xfree(response);
1497: xfree(prompt);
1498: }
1.90 markus 1499: packet_check_eom(); /* done with parsing incoming message. */
1.23 markus 1500:
1.85 markus 1501: packet_add_padding(64);
1.23 markus 1502: packet_send();
1.68 markus 1503: }
1504:
1.100 markus 1505: static int
1.105 deraadt 1506: ssh_keysign(Key *key, u_char **sigp, u_int *lenp,
1.100 markus 1507: u_char *data, u_int datalen)
1508: {
1509: Buffer b;
1.101 markus 1510: struct stat st;
1.100 markus 1511: pid_t pid;
1.103 markus 1512: int to[2], from[2], status, version = 2;
1.100 markus 1513:
1.109 markus 1514: debug2("ssh_keysign called");
1.100 markus 1515:
1.101 markus 1516: if (stat(_PATH_SSH_KEY_SIGN, &st) < 0) {
1.179 dtucker 1517: error("ssh_keysign: not installed: %s", strerror(errno));
1.101 markus 1518: return -1;
1519: }
1.100 markus 1520: if (fflush(stdout) != 0)
1521: error("ssh_keysign: fflush: %s", strerror(errno));
1522: if (pipe(to) < 0) {
1523: error("ssh_keysign: pipe: %s", strerror(errno));
1524: return -1;
1525: }
1526: if (pipe(from) < 0) {
1527: error("ssh_keysign: pipe: %s", strerror(errno));
1528: return -1;
1529: }
1530: if ((pid = fork()) < 0) {
1531: error("ssh_keysign: fork: %s", strerror(errno));
1532: return -1;
1533: }
1534: if (pid == 0) {
1.174 dtucker 1535: /* keep the socket on exec */
1536: fcntl(packet_get_connection_in(), F_SETFD, 0);
1.155 markus 1537: permanently_drop_suid(getuid());
1.100 markus 1538: close(from[0]);
1539: if (dup2(from[1], STDOUT_FILENO) < 0)
1540: fatal("ssh_keysign: dup2: %s", strerror(errno));
1541: close(to[1]);
1542: if (dup2(to[0], STDIN_FILENO) < 0)
1543: fatal("ssh_keysign: dup2: %s", strerror(errno));
1.103 markus 1544: close(from[1]);
1545: close(to[0]);
1.102 markus 1546: execl(_PATH_SSH_KEY_SIGN, _PATH_SSH_KEY_SIGN, (char *) 0);
1.100 markus 1547: fatal("ssh_keysign: exec(%s): %s", _PATH_SSH_KEY_SIGN,
1548: strerror(errno));
1549: }
1550: close(from[1]);
1551: close(to[0]);
1552:
1553: buffer_init(&b);
1.103 markus 1554: buffer_put_int(&b, packet_get_connection_in()); /* send # of socket */
1.100 markus 1555: buffer_put_string(&b, data, datalen);
1.131 djm 1556: if (ssh_msg_send(to[1], version, &b) == -1)
1557: fatal("ssh_keysign: couldn't send request");
1.100 markus 1558:
1.110 djm 1559: if (ssh_msg_recv(from[0], &b) < 0) {
1.101 markus 1560: error("ssh_keysign: no reply");
1.134 markus 1561: buffer_free(&b);
1.100 markus 1562: return -1;
1563: }
1.101 markus 1564: close(from[0]);
1565: close(to[1]);
1566:
1.103 markus 1567: while (waitpid(pid, &status, 0) < 0)
1568: if (errno != EINTR)
1569: break;
1.101 markus 1570:
1.100 markus 1571: if (buffer_get_char(&b) != version) {
1.101 markus 1572: error("ssh_keysign: bad version");
1.134 markus 1573: buffer_free(&b);
1.100 markus 1574: return -1;
1575: }
1576: *sigp = buffer_get_string(&b, lenp);
1.134 markus 1577: buffer_free(&b);
1.100 markus 1578:
1579: return 0;
1580: }
1581:
1.68 markus 1582: int
1583: userauth_hostbased(Authctxt *authctxt)
1584: {
1585: Key *private = NULL;
1.100 markus 1586: Sensitive *sensitive = authctxt->sensitive;
1.68 markus 1587: Buffer b;
1588: u_char *signature, *blob;
1.179 dtucker 1589: char *chost, *pkalg, *p;
1.72 markus 1590: const char *service;
1.68 markus 1591: u_int blen, slen;
1.176 dtucker 1592: int ok, i, found = 0;
1.68 markus 1593:
1594: /* check for a useful key */
1.100 markus 1595: for (i = 0; i < sensitive->nkeys; i++) {
1596: private = sensitive->keys[i];
1.68 markus 1597: if (private && private->type != KEY_RSA1) {
1598: found = 1;
1599: /* we take and free the key */
1.100 markus 1600: sensitive->keys[i] = NULL;
1.68 markus 1601: break;
1602: }
1603: }
1604: if (!found) {
1.109 markus 1605: debug("No more client hostkeys for hostbased authentication.");
1.68 markus 1606: return 0;
1607: }
1608: if (key_to_blob(private, &blob, &blen) == 0) {
1609: key_free(private);
1610: return 0;
1611: }
1.84 markus 1612: /* figure out a name for the client host */
1.179 dtucker 1613: p = get_local_name(packet_get_connection_in());
1.84 markus 1614: if (p == NULL) {
1615: error("userauth_hostbased: cannot get local ipaddr/name");
1616: key_free(private);
1.148 djm 1617: xfree(blob);
1.84 markus 1618: return 0;
1619: }
1.150 djm 1620: xasprintf(&chost, "%s.", p);
1.84 markus 1621: debug2("userauth_hostbased: chost %s", chost);
1.112 markus 1622: xfree(p);
1.84 markus 1623:
1.72 markus 1624: service = datafellows & SSH_BUG_HBSERVICE ? "ssh-userauth" :
1625: authctxt->service;
1.68 markus 1626: pkalg = xstrdup(key_ssh_name(private));
1627: buffer_init(&b);
1628: /* construct data */
1.72 markus 1629: buffer_put_string(&b, session_id2, session_id2_len);
1.68 markus 1630: buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
1631: buffer_put_cstring(&b, authctxt->server_user);
1.72 markus 1632: buffer_put_cstring(&b, service);
1.68 markus 1633: buffer_put_cstring(&b, authctxt->method->name);
1634: buffer_put_cstring(&b, pkalg);
1635: buffer_put_string(&b, blob, blen);
1636: buffer_put_cstring(&b, chost);
1637: buffer_put_cstring(&b, authctxt->local_user);
1638: #ifdef DEBUG_PK
1639: buffer_dump(&b);
1640: #endif
1.100 markus 1641: if (sensitive->external_keysign)
1642: ok = ssh_keysign(private, &signature, &slen,
1643: buffer_ptr(&b), buffer_len(&b));
1644: else
1645: ok = key_sign(private, &signature, &slen,
1646: buffer_ptr(&b), buffer_len(&b));
1.68 markus 1647: key_free(private);
1648: buffer_free(&b);
1649: if (ok != 0) {
1650: error("key_sign failed");
1651: xfree(chost);
1652: xfree(pkalg);
1.148 djm 1653: xfree(blob);
1.68 markus 1654: return 0;
1655: }
1656: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1657: packet_put_cstring(authctxt->server_user);
1658: packet_put_cstring(authctxt->service);
1659: packet_put_cstring(authctxt->method->name);
1660: packet_put_cstring(pkalg);
1661: packet_put_string(blob, blen);
1662: packet_put_cstring(chost);
1663: packet_put_cstring(authctxt->local_user);
1664: packet_put_string(signature, slen);
1665: memset(signature, 's', slen);
1666: xfree(signature);
1667: xfree(chost);
1668: xfree(pkalg);
1.148 djm 1669: xfree(blob);
1.68 markus 1670:
1671: packet_send();
1672: return 1;
1.23 markus 1673: }
1.20 markus 1674:
1.170 djm 1675: #ifdef JPAKE
1676: int
1677: userauth_jpake(Authctxt *authctxt)
1678: {
1679: struct jpake_ctx *pctx;
1680: u_char *x1_proof, *x2_proof;
1681: u_int x1_proof_len, x2_proof_len;
1682: static int attempt = 0; /* XXX share with userauth_password's? */
1683:
1684: if (attempt++ >= options.number_of_password_prompts)
1685: return 0;
1686: if (attempt != 1)
1687: error("Permission denied, please try again.");
1688:
1689: if (authctxt->methoddata != NULL)
1690: fatal("%s: authctxt->methoddata already set (%p)",
1691: __func__, authctxt->methoddata);
1692:
1693: authctxt->methoddata = pctx = jpake_new();
1694:
1695: /*
1696: * Send request immediately, to get the protocol going while
1697: * we do the initial computations.
1698: */
1699: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1700: packet_put_cstring(authctxt->server_user);
1701: packet_put_cstring(authctxt->service);
1702: packet_put_cstring(authctxt->method->name);
1703: packet_send();
1704: packet_write_wait();
1705:
1706: jpake_step1(pctx->grp,
1707: &pctx->client_id, &pctx->client_id_len,
1708: &pctx->x1, &pctx->x2, &pctx->g_x1, &pctx->g_x2,
1709: &x1_proof, &x1_proof_len,
1710: &x2_proof, &x2_proof_len);
1711:
1712: JPAKE_DEBUG_CTX((pctx, "step 1 sending in %s", __func__));
1713:
1714: packet_start(SSH2_MSG_USERAUTH_JPAKE_CLIENT_STEP1);
1715: packet_put_string(pctx->client_id, pctx->client_id_len);
1716: packet_put_bignum2(pctx->g_x1);
1717: packet_put_bignum2(pctx->g_x2);
1718: packet_put_string(x1_proof, x1_proof_len);
1719: packet_put_string(x2_proof, x2_proof_len);
1720: packet_send();
1721:
1722: bzero(x1_proof, x1_proof_len);
1723: bzero(x2_proof, x2_proof_len);
1724: xfree(x1_proof);
1725: xfree(x2_proof);
1726:
1727: /* Expect step 1 packet from peer */
1728: dispatch_set(SSH2_MSG_USERAUTH_JPAKE_SERVER_STEP1,
1729: input_userauth_jpake_server_step1);
1.172 djm 1730: dispatch_set(SSH2_MSG_USERAUTH_SUCCESS,
1731: &input_userauth_success_unexpected);
1.170 djm 1732:
1733: return 1;
1734: }
1735:
1736: void
1737: userauth_jpake_cleanup(Authctxt *authctxt)
1738: {
1739: debug3("%s: clean up", __func__);
1740: if (authctxt->methoddata != NULL) {
1741: jpake_free(authctxt->methoddata);
1742: authctxt->methoddata = NULL;
1743: }
1.172 djm 1744: dispatch_set(SSH2_MSG_USERAUTH_SUCCESS, &input_userauth_success);
1.170 djm 1745: }
1746: #endif /* JPAKE */
1747:
1.20 markus 1748: /* find auth method */
1749:
1750: /*
1751: * given auth method name, if configurable options permit this method fill
1752: * in auth_ident field and return true, otherwise return false.
1753: */
1.76 itojun 1754: static int
1.20 markus 1755: authmethod_is_enabled(Authmethod *method)
1756: {
1757: if (method == NULL)
1758: return 0;
1759: /* return false if options indicate this method is disabled */
1760: if (method->enabled == NULL || *method->enabled == 0)
1761: return 0;
1762: /* return false if batch mode is enabled but method needs interactive mode */
1763: if (method->batch_flag != NULL && *method->batch_flag != 0)
1764: return 0;
1765: return 1;
1766: }
1767:
1.76 itojun 1768: static Authmethod *
1.20 markus 1769: authmethod_lookup(const char *name)
1.1 markus 1770: {
1.20 markus 1771: Authmethod *method = NULL;
1772: if (name != NULL)
1773: for (method = authmethods; method->name != NULL; method++)
1774: if (strcmp(name, method->name) == 0)
1775: return method;
1776: debug2("Unrecognized authentication method name: %s", name ? name : "NULL");
1777: return NULL;
1778: }
1.1 markus 1779:
1.53 markus 1780: /* XXX internal state */
1781: static Authmethod *current = NULL;
1782: static char *supported = NULL;
1783: static char *preferred = NULL;
1.105 deraadt 1784:
1.20 markus 1785: /*
1786: * Given the authentication method list sent by the server, return the
1787: * next method we should try. If the server initially sends a nil list,
1.67 markus 1788: * use a built-in default list.
1.41 stevesk 1789: */
1.76 itojun 1790: static Authmethod *
1.20 markus 1791: authmethod_get(char *authlist)
1792: {
1.53 markus 1793: char *name = NULL;
1.97 markus 1794: u_int next;
1.41 stevesk 1795:
1.20 markus 1796: /* Use a suitable default if we're passed a nil list. */
1797: if (authlist == NULL || strlen(authlist) == 0)
1.53 markus 1798: authlist = options.preferred_authentications;
1.20 markus 1799:
1.53 markus 1800: if (supported == NULL || strcmp(authlist, supported) != 0) {
1801: debug3("start over, passed a different list %s", authlist);
1802: if (supported != NULL)
1803: xfree(supported);
1804: supported = xstrdup(authlist);
1805: preferred = options.preferred_authentications;
1806: debug3("preferred %s", preferred);
1807: current = NULL;
1808: } else if (current != NULL && authmethod_is_enabled(current))
1809: return current;
1.20 markus 1810:
1.53 markus 1811: for (;;) {
1812: if ((name = match_list(preferred, supported, &next)) == NULL) {
1.109 markus 1813: debug("No more authentication methods to try.");
1.53 markus 1814: current = NULL;
1815: return NULL;
1816: }
1817: preferred += next;
1.23 markus 1818: debug3("authmethod_lookup %s", name);
1.53 markus 1819: debug3("remaining preferred: %s", preferred);
1820: if ((current = authmethod_lookup(name)) != NULL &&
1821: authmethod_is_enabled(current)) {
1.23 markus 1822: debug3("authmethod_is_enabled %s", name);
1.109 markus 1823: debug("Next authentication method: %s", name);
1.53 markus 1824: return current;
1.23 markus 1825: }
1.1 markus 1826: }
1.53 markus 1827: }
1.1 markus 1828:
1.79 stevesk 1829: static char *
1.53 markus 1830: authmethods_get(void)
1831: {
1832: Authmethod *method = NULL;
1.93 markus 1833: Buffer b;
1834: char *list;
1.27 provos 1835:
1.93 markus 1836: buffer_init(&b);
1.53 markus 1837: for (method = authmethods; method->name != NULL; method++) {
1838: if (authmethod_is_enabled(method)) {
1.93 markus 1839: if (buffer_len(&b) > 0)
1840: buffer_append(&b, ",", 1);
1841: buffer_append(&b, method->name, strlen(method->name));
1.53 markus 1842: }
1843: }
1.93 markus 1844: buffer_append(&b, "\0", 1);
1845: list = xstrdup(buffer_ptr(&b));
1846: buffer_free(&b);
1847: return list;
1.1 markus 1848: }
1.170 djm 1849: