Annotation of src/usr.bin/ssh/sshconnect2.c, Revision 1.57
1.1 markus 1: /*
2: * Copyright (c) 2000 Markus Friedl. All rights reserved.
3: *
4: * Redistribution and use in source and binary forms, with or without
5: * modification, are permitted provided that the following conditions
6: * are met:
7: * 1. Redistributions of source code must retain the above copyright
8: * notice, this list of conditions and the following disclaimer.
9: * 2. Redistributions in binary form must reproduce the above copyright
10: * notice, this list of conditions and the following disclaimer in the
11: * documentation and/or other materials provided with the distribution.
12: *
13: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
14: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
15: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
16: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
17: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
18: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
19: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
20: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
21: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
22: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
23: */
24:
25: #include "includes.h"
1.57 ! provos 26: RCSID("$OpenBSD: sshconnect2.c,v 1.56 2001/03/26 08:07:09 markus Exp $");
1.1 markus 27:
28: #include <openssl/bn.h>
29: #include <openssl/md5.h>
30: #include <openssl/dh.h>
31: #include <openssl/hmac.h>
32:
33: #include "ssh.h"
1.37 markus 34: #include "ssh2.h"
1.1 markus 35: #include "xmalloc.h"
36: #include "rsa.h"
37: #include "buffer.h"
38: #include "packet.h"
39: #include "uidswap.h"
40: #include "compat.h"
41: #include "bufaux.h"
1.37 markus 42: #include "cipher.h"
1.1 markus 43: #include "kex.h"
44: #include "myproposal.h"
45: #include "key.h"
46: #include "sshconnect.h"
47: #include "authfile.h"
1.23 markus 48: #include "cli.h"
1.57 ! provos 49: #include "dh.h"
1.20 markus 50: #include "dispatch.h"
1.17 markus 51: #include "authfd.h"
1.37 markus 52: #include "log.h"
53: #include "readconf.h"
54: #include "readpass.h"
1.53 markus 55: #include "match.h"
1.1 markus 56:
1.22 provos 57: void ssh_dh1_client(Kex *, char *, struct sockaddr *, Buffer *, Buffer *);
58: void ssh_dhgex_client(Kex *, char *, struct sockaddr *, Buffer *, Buffer *);
59:
1.1 markus 60: /* import */
61: extern char *client_version_string;
62: extern char *server_version_string;
63: extern Options options;
64:
65: /*
66: * SSH2 key exchange
67: */
68:
1.32 markus 69: u_char *session_id2 = NULL;
1.1 markus 70: int session_id2_len = 0;
71:
72: void
1.22 provos 73: ssh_kex2(char *host, struct sockaddr *hostaddr)
74: {
75: int i, plen;
76: Kex *kex;
77: Buffer *client_kexinit, *server_kexinit;
78: char *sprop[PROPOSAL_MAX];
79:
1.29 markus 80: if (options.ciphers == (char *)-1) {
81: log("No valid ciphers for protocol version 2 given, using defaults.");
82: options.ciphers = NULL;
1.24 markus 83: }
1.22 provos 84: if (options.ciphers != NULL) {
85: myproposal[PROPOSAL_ENC_ALGS_CTOS] =
86: myproposal[PROPOSAL_ENC_ALGS_STOC] = options.ciphers;
87: }
88: if (options.compression) {
1.47 markus 89: myproposal[PROPOSAL_COMP_ALGS_CTOS] =
1.22 provos 90: myproposal[PROPOSAL_COMP_ALGS_STOC] = "zlib";
91: } else {
1.47 markus 92: myproposal[PROPOSAL_COMP_ALGS_CTOS] =
1.22 provos 93: myproposal[PROPOSAL_COMP_ALGS_STOC] = "none";
1.47 markus 94: }
95: if (options.macs != NULL) {
96: myproposal[PROPOSAL_MAC_ALGS_CTOS] =
97: myproposal[PROPOSAL_MAC_ALGS_STOC] = options.macs;
1.22 provos 98: }
1.55 djm 99:
100: myproposal[PROPOSAL_ENC_ALGS_STOC] =
101: compat_cipher_proposal(myproposal[PROPOSAL_ENC_ALGS_STOC]);
1.22 provos 102:
103: /* buffers with raw kexinit messages */
104: server_kexinit = xmalloc(sizeof(*server_kexinit));
105: buffer_init(server_kexinit);
106: client_kexinit = kex_init(myproposal);
107:
108: /* algorithm negotiation */
109: kex_exchange_kexinit(client_kexinit, server_kexinit, sprop);
110: kex = kex_choose_conf(myproposal, sprop, 0);
111: for (i = 0; i < PROPOSAL_MAX; i++)
112: xfree(sprop[i]);
113:
114: /* server authentication and session key agreement */
115: switch(kex->kex_type) {
116: case DH_GRP1_SHA1:
117: ssh_dh1_client(kex, host, hostaddr,
118: client_kexinit, server_kexinit);
119: break;
120: case DH_GEX_SHA1:
121: ssh_dhgex_client(kex, host, hostaddr, client_kexinit,
122: server_kexinit);
123: break;
124: default:
125: fatal("Unsupported key exchange %d", kex->kex_type);
126: }
127:
128: buffer_free(client_kexinit);
129: buffer_free(server_kexinit);
130: xfree(client_kexinit);
131: xfree(server_kexinit);
132:
133: debug("Wait SSH2_MSG_NEWKEYS.");
134: packet_read_expect(&plen, SSH2_MSG_NEWKEYS);
135: packet_done();
136: debug("GOT SSH2_MSG_NEWKEYS.");
137:
138: debug("send SSH2_MSG_NEWKEYS.");
139: packet_start(SSH2_MSG_NEWKEYS);
140: packet_send();
141: packet_write_wait();
142: debug("done: send SSH2_MSG_NEWKEYS.");
143:
144: #ifdef DEBUG_KEXDH
145: /* send 1st encrypted/maced/compressed message */
146: packet_start(SSH2_MSG_IGNORE);
147: packet_put_cstring("markus");
148: packet_send();
149: packet_write_wait();
150: #endif
151: debug("done: KEX2.");
152: }
153:
154: /* diffie-hellman-group1-sha1 */
155:
156: void
1.41 stevesk 157: ssh_dh1_client(Kex *kex, char *host, struct sockaddr *hostaddr,
1.22 provos 158: Buffer *client_kexinit, Buffer *server_kexinit)
1.1 markus 159: {
1.19 markus 160: #ifdef DEBUG_KEXDH
161: int i;
162: #endif
1.11 markus 163: int plen, dlen;
1.32 markus 164: u_int klen, kout;
1.1 markus 165: char *signature = NULL;
1.32 markus 166: u_int slen;
1.1 markus 167: char *server_host_key_blob = NULL;
168: Key *server_host_key;
1.32 markus 169: u_int sbloblen;
1.1 markus 170: DH *dh;
171: BIGNUM *dh_server_pub = 0;
172: BIGNUM *shared_secret = 0;
1.32 markus 173: u_char *kbuf;
174: u_char *hash;
1.1 markus 175:
176: debug("Sending SSH2_MSG_KEXDH_INIT.");
177: /* generate and send 'e', client DH public key */
178: dh = dh_new_group1();
1.50 markus 179: dh_gen_key(dh, kex->we_need * 8);
1.1 markus 180: packet_start(SSH2_MSG_KEXDH_INIT);
181: packet_put_bignum2(dh->pub_key);
182: packet_send();
183: packet_write_wait();
184:
185: #ifdef DEBUG_KEXDH
186: fprintf(stderr, "\np= ");
1.19 markus 187: BN_print_fp(stderr, dh->p);
1.1 markus 188: fprintf(stderr, "\ng= ");
1.19 markus 189: BN_print_fp(stderr, dh->g);
1.1 markus 190: fprintf(stderr, "\npub= ");
1.19 markus 191: BN_print_fp(stderr, dh->pub_key);
1.1 markus 192: fprintf(stderr, "\n");
193: DHparams_print_fp(stderr, dh);
194: #endif
195:
196: debug("Wait SSH2_MSG_KEXDH_REPLY.");
197:
1.11 markus 198: packet_read_expect(&plen, SSH2_MSG_KEXDH_REPLY);
1.1 markus 199:
200: debug("Got SSH2_MSG_KEXDH_REPLY.");
201:
202: /* key, cert */
203: server_host_key_blob = packet_get_string(&sbloblen);
1.28 markus 204: server_host_key = key_from_blob(server_host_key_blob, sbloblen);
1.1 markus 205: if (server_host_key == NULL)
206: fatal("cannot decode server_host_key_blob");
207:
208: check_host_key(host, hostaddr, server_host_key,
1.22 provos 209: options.user_hostfile2, options.system_hostfile2);
1.1 markus 210:
211: /* DH paramter f, server public DH key */
212: dh_server_pub = BN_new();
213: if (dh_server_pub == NULL)
214: fatal("dh_server_pub == NULL");
215: packet_get_bignum2(dh_server_pub, &dlen);
216:
217: #ifdef DEBUG_KEXDH
218: fprintf(stderr, "\ndh_server_pub= ");
1.19 markus 219: BN_print_fp(stderr, dh_server_pub);
1.1 markus 220: fprintf(stderr, "\n");
221: debug("bits %d", BN_num_bits(dh_server_pub));
222: #endif
223:
224: /* signed H */
225: signature = packet_get_string(&slen);
226: packet_done();
227:
228: if (!dh_pub_is_valid(dh, dh_server_pub))
229: packet_disconnect("bad server public DH value");
230:
231: klen = DH_size(dh);
232: kbuf = xmalloc(klen);
233: kout = DH_compute_key(kbuf, dh_server_pub, dh);
234: #ifdef DEBUG_KEXDH
235: debug("shared secret: len %d/%d", klen, kout);
236: fprintf(stderr, "shared secret == ");
237: for (i = 0; i< kout; i++)
238: fprintf(stderr, "%02x", (kbuf[i])&0xff);
239: fprintf(stderr, "\n");
240: #endif
241: shared_secret = BN_new();
242:
243: BN_bin2bn(kbuf, kout, shared_secret);
244: memset(kbuf, 0, klen);
245: xfree(kbuf);
246:
247: /* calc and verify H */
248: hash = kex_hash(
249: client_version_string,
250: server_version_string,
251: buffer_ptr(client_kexinit), buffer_len(client_kexinit),
252: buffer_ptr(server_kexinit), buffer_len(server_kexinit),
253: server_host_key_blob, sbloblen,
254: dh->pub_key,
255: dh_server_pub,
256: shared_secret
257: );
1.3 markus 258: xfree(server_host_key_blob);
1.11 markus 259: DH_free(dh);
1.38 stevesk 260: BN_free(dh_server_pub);
1.1 markus 261: #ifdef DEBUG_KEXDH
262: fprintf(stderr, "hash == ");
263: for (i = 0; i< 20; i++)
264: fprintf(stderr, "%02x", (hash[i])&0xff);
265: fprintf(stderr, "\n");
266: #endif
1.32 markus 267: if (key_verify(server_host_key, (u_char *)signature, slen, hash, 20) != 1)
1.28 markus 268: fatal("key_verify failed for server_host_key");
1.1 markus 269: key_free(server_host_key);
1.38 stevesk 270: xfree(signature);
1.1 markus 271:
272: kex_derive_keys(kex, hash, shared_secret);
1.38 stevesk 273: BN_clear_free(shared_secret);
1.1 markus 274: packet_set_kex(kex);
275:
276: /* save session id */
277: session_id2_len = 20;
278: session_id2 = xmalloc(session_id2_len);
279: memcpy(session_id2, hash, session_id2_len);
1.11 markus 280: }
281:
1.22 provos 282: /* diffie-hellman-group-exchange-sha1 */
283:
284: /*
285: * Estimates the group order for a Diffie-Hellman group that has an
286: * attack complexity approximately the same as O(2**bits). Estimate
287: * with: O(exp(1.9223 * (ln q)^(1/3) (ln ln q)^(2/3)))
288: */
289:
290: int
291: dh_estimate(int bits)
292: {
1.41 stevesk 293:
1.22 provos 294: if (bits < 64)
295: return (512); /* O(2**63) */
296: if (bits < 128)
297: return (1024); /* O(2**86) */
298: if (bits < 192)
299: return (2048); /* O(2**116) */
300: return (4096); /* O(2**156) */
301: }
302:
1.11 markus 303: void
1.22 provos 304: ssh_dhgex_client(Kex *kex, char *host, struct sockaddr *hostaddr,
305: Buffer *client_kexinit, Buffer *server_kexinit)
1.11 markus 306: {
1.22 provos 307: #ifdef DEBUG_KEXDH
308: int i;
309: #endif
310: int plen, dlen;
1.32 markus 311: u_int klen, kout;
1.22 provos 312: char *signature = NULL;
1.57 ! provos 313: u_int slen, nbits, min, max;
1.22 provos 314: char *server_host_key_blob = NULL;
315: Key *server_host_key;
1.32 markus 316: u_int sbloblen;
1.22 provos 317: DH *dh;
318: BIGNUM *dh_server_pub = 0;
319: BIGNUM *shared_secret = 0;
320: BIGNUM *p = 0, *g = 0;
1.32 markus 321: u_char *kbuf;
322: u_char *hash;
1.22 provos 323:
1.50 markus 324: nbits = dh_estimate(kex->we_need * 8);
1.22 provos 325:
1.57 ! provos 326: if (datafellows & SSH_OLD_DHGEX) {
! 327: debug("Sending SSH2_MSG_KEX_DH_GEX_REQUEST_OLD.");
! 328:
! 329: /* Old GEX request */
! 330: packet_start(SSH2_MSG_KEX_DH_GEX_REQUEST_OLD);
! 331: packet_put_int(nbits);
! 332: min = DH_GRP_MIN;
! 333: max = DH_GRP_MAX;
! 334: } else {
! 335: debug("Sending SSH2_MSG_KEX_DH_GEX_REQUEST.");
! 336:
! 337: /* New GEX request */
! 338: min = DH_GRP_MIN;
! 339: max = MIN(DH_GRP_MAX, nbits * 1.25);
! 340:
! 341: packet_start(SSH2_MSG_KEX_DH_GEX_REQUEST);
! 342: packet_put_int(min);
! 343: packet_put_int(nbits);
! 344: packet_put_int(max);
! 345: }
1.22 provos 346: packet_send();
347: packet_write_wait();
1.11 markus 348:
1.22 provos 349: #ifdef DEBUG_KEXDH
1.57 ! provos 350: fprintf(stderr, "\nmin = %d, nbits = %d, max = %d", min, nbits, max);
1.22 provos 351: #endif
1.11 markus 352:
1.22 provos 353: debug("Wait SSH2_MSG_KEX_DH_GEX_GROUP.");
1.11 markus 354:
1.22 provos 355: packet_read_expect(&plen, SSH2_MSG_KEX_DH_GEX_GROUP);
1.11 markus 356:
1.22 provos 357: debug("Got SSH2_MSG_KEX_DH_GEX_GROUP.");
1.11 markus 358:
1.22 provos 359: if ((p = BN_new()) == NULL)
360: fatal("BN_new");
361: packet_get_bignum2(p, &dlen);
362: if ((g = BN_new()) == NULL)
363: fatal("BN_new");
364: packet_get_bignum2(g, &dlen);
1.57 ! provos 365:
! 366: if (BN_num_bits(p) < min || BN_num_bits(p) > max)
! 367: fatal("DH_GEX group out of range: %d !< %d !< %d",
! 368: min, BN_num_bits(p), max);
! 369:
1.36 stevesk 370: dh = dh_new_group(g, p);
1.31 provos 371:
1.50 markus 372: dh_gen_key(dh, kex->we_need * 8);
1.1 markus 373:
1.22 provos 374: #ifdef DEBUG_KEXDH
375: fprintf(stderr, "\np= ");
376: BN_print_fp(stderr, dh->p);
377: fprintf(stderr, "\ng= ");
378: BN_print_fp(stderr, dh->g);
379: fprintf(stderr, "\npub= ");
380: BN_print_fp(stderr, dh->pub_key);
381: fprintf(stderr, "\n");
382: DHparams_print_fp(stderr, dh);
383: #endif
1.1 markus 384:
1.22 provos 385: debug("Sending SSH2_MSG_KEX_DH_GEX_INIT.");
386: /* generate and send 'e', client DH public key */
387: packet_start(SSH2_MSG_KEX_DH_GEX_INIT);
388: packet_put_bignum2(dh->pub_key);
1.1 markus 389: packet_send();
390: packet_write_wait();
391:
1.22 provos 392: debug("Wait SSH2_MSG_KEX_DH_GEX_REPLY.");
393:
394: packet_read_expect(&plen, SSH2_MSG_KEX_DH_GEX_REPLY);
395:
396: debug("Got SSH2_MSG_KEXDH_REPLY.");
397:
398: /* key, cert */
399: server_host_key_blob = packet_get_string(&sbloblen);
1.28 markus 400: server_host_key = key_from_blob(server_host_key_blob, sbloblen);
1.22 provos 401: if (server_host_key == NULL)
402: fatal("cannot decode server_host_key_blob");
403:
404: check_host_key(host, hostaddr, server_host_key,
405: options.user_hostfile2, options.system_hostfile2);
406:
407: /* DH paramter f, server public DH key */
408: dh_server_pub = BN_new();
409: if (dh_server_pub == NULL)
410: fatal("dh_server_pub == NULL");
411: packet_get_bignum2(dh_server_pub, &dlen);
412:
413: #ifdef DEBUG_KEXDH
414: fprintf(stderr, "\ndh_server_pub= ");
415: BN_print_fp(stderr, dh_server_pub);
416: fprintf(stderr, "\n");
417: debug("bits %d", BN_num_bits(dh_server_pub));
418: #endif
419:
420: /* signed H */
421: signature = packet_get_string(&slen);
422: packet_done();
423:
424: if (!dh_pub_is_valid(dh, dh_server_pub))
425: packet_disconnect("bad server public DH value");
426:
427: klen = DH_size(dh);
428: kbuf = xmalloc(klen);
429: kout = DH_compute_key(kbuf, dh_server_pub, dh);
430: #ifdef DEBUG_KEXDH
431: debug("shared secret: len %d/%d", klen, kout);
432: fprintf(stderr, "shared secret == ");
433: for (i = 0; i< kout; i++)
434: fprintf(stderr, "%02x", (kbuf[i])&0xff);
435: fprintf(stderr, "\n");
436: #endif
437: shared_secret = BN_new();
438:
439: BN_bin2bn(kbuf, kout, shared_secret);
440: memset(kbuf, 0, klen);
441: xfree(kbuf);
442:
443: /* calc and verify H */
444: hash = kex_hash_gex(
445: client_version_string,
446: server_version_string,
447: buffer_ptr(client_kexinit), buffer_len(client_kexinit),
448: buffer_ptr(server_kexinit), buffer_len(server_kexinit),
449: server_host_key_blob, sbloblen,
1.41 stevesk 450: nbits, dh->p, dh->g,
1.22 provos 451: dh->pub_key,
452: dh_server_pub,
453: shared_secret
454: );
455: xfree(server_host_key_blob);
456: DH_free(dh);
1.38 stevesk 457: BN_free(dh_server_pub);
1.1 markus 458: #ifdef DEBUG_KEXDH
1.22 provos 459: fprintf(stderr, "hash == ");
460: for (i = 0; i< 20; i++)
461: fprintf(stderr, "%02x", (hash[i])&0xff);
462: fprintf(stderr, "\n");
1.1 markus 463: #endif
1.32 markus 464: if (key_verify(server_host_key, (u_char *)signature, slen, hash, 20) != 1)
1.28 markus 465: fatal("key_verify failed for server_host_key");
1.22 provos 466: key_free(server_host_key);
1.38 stevesk 467: xfree(signature);
1.22 provos 468:
469: kex_derive_keys(kex, hash, shared_secret);
1.38 stevesk 470: BN_clear_free(shared_secret);
1.22 provos 471: packet_set_kex(kex);
472:
473: /* save session id */
474: session_id2_len = 20;
475: session_id2 = xmalloc(session_id2_len);
476: memcpy(session_id2, hash, session_id2_len);
1.1 markus 477: }
1.11 markus 478:
1.1 markus 479: /*
480: * Authenticate user
481: */
1.20 markus 482:
483: typedef struct Authctxt Authctxt;
484: typedef struct Authmethod Authmethod;
485:
486: typedef int sign_cb_fn(
487: Authctxt *authctxt, Key *key,
1.32 markus 488: u_char **sigp, int *lenp, u_char *data, int datalen);
1.20 markus 489:
490: struct Authctxt {
491: const char *server_user;
492: const char *host;
493: const char *service;
494: AuthenticationConnection *agent;
1.23 markus 495: Authmethod *method;
1.20 markus 496: int success;
1.51 markus 497: char *authlist;
498: Key *last_key;
499: sign_cb_fn *last_key_sign;
500: int last_key_hint;
1.20 markus 501: };
502: struct Authmethod {
503: char *name; /* string to compare against server's list */
504: int (*userauth)(Authctxt *authctxt);
505: int *enabled; /* flag in option struct that enables method */
506: int *batch_flag; /* flag in option struct that disables method */
507: };
508:
509: void input_userauth_success(int type, int plen, void *ctxt);
510: void input_userauth_failure(int type, int plen, void *ctxt);
1.35 markus 511: void input_userauth_banner(int type, int plen, void *ctxt);
1.20 markus 512: void input_userauth_error(int type, int plen, void *ctxt);
1.23 markus 513: void input_userauth_info_req(int type, int plen, void *ctxt);
1.51 markus 514: void input_userauth_pk_ok(int type, int plen, void *ctxt);
1.23 markus 515:
516: int userauth_none(Authctxt *authctxt);
1.20 markus 517: int userauth_pubkey(Authctxt *authctxt);
518: int userauth_passwd(Authctxt *authctxt);
1.23 markus 519: int userauth_kbdint(Authctxt *authctxt);
1.20 markus 520:
1.51 markus 521: void userauth(Authctxt *authctxt, char *authlist);
522:
523: int
524: sign_and_send_pubkey(Authctxt *authctxt, Key *k,
525: sign_cb_fn *sign_callback);
526: void clear_auth_state(Authctxt *authctxt);
527:
1.23 markus 528: Authmethod *authmethod_get(char *authlist);
529: Authmethod *authmethod_lookup(const char *name);
1.53 markus 530: char *authmethods_get(void);
1.20 markus 531:
532: Authmethod authmethods[] = {
533: {"publickey",
534: userauth_pubkey,
1.28 markus 535: &options.pubkey_authentication,
1.20 markus 536: NULL},
537: {"password",
538: userauth_passwd,
539: &options.password_authentication,
540: &options.batch_mode},
1.23 markus 541: {"keyboard-interactive",
542: userauth_kbdint,
543: &options.kbd_interactive_authentication,
544: &options.batch_mode},
545: {"none",
546: userauth_none,
547: NULL,
548: NULL},
1.20 markus 549: {NULL, NULL, NULL, NULL}
550: };
551:
552: void
553: ssh_userauth2(const char *server_user, char *host)
554: {
555: Authctxt authctxt;
556: int type;
557: int plen;
1.39 markus 558:
559: if (options.challenge_reponse_authentication)
560: options.kbd_interactive_authentication = 1;
1.20 markus 561:
562: debug("send SSH2_MSG_SERVICE_REQUEST");
563: packet_start(SSH2_MSG_SERVICE_REQUEST);
564: packet_put_cstring("ssh-userauth");
565: packet_send();
566: packet_write_wait();
567: type = packet_read(&plen);
568: if (type != SSH2_MSG_SERVICE_ACCEPT) {
569: fatal("denied SSH2_MSG_SERVICE_ACCEPT: %d", type);
570: }
571: if (packet_remaining() > 0) {
572: char *reply = packet_get_string(&plen);
573: debug("service_accept: %s", reply);
574: xfree(reply);
575: } else {
576: debug("buggy server: service_accept w/o service");
577: }
578: packet_done();
579: debug("got SSH2_MSG_SERVICE_ACCEPT");
580:
1.53 markus 581: if (options.preferred_authentications == NULL)
582: options.preferred_authentications = authmethods_get();
583:
1.20 markus 584: /* setup authentication context */
585: authctxt.agent = ssh_get_authentication_connection();
586: authctxt.server_user = server_user;
587: authctxt.host = host;
588: authctxt.service = "ssh-connection"; /* service name */
589: authctxt.success = 0;
1.23 markus 590: authctxt.method = authmethod_lookup("none");
1.51 markus 591: authctxt.authlist = NULL;
1.23 markus 592: if (authctxt.method == NULL)
593: fatal("ssh_userauth2: internal error: cannot send userauth none request");
1.20 markus 594:
595: /* initial userauth request */
1.23 markus 596: userauth_none(&authctxt);
1.20 markus 597:
598: dispatch_init(&input_userauth_error);
599: dispatch_set(SSH2_MSG_USERAUTH_SUCCESS, &input_userauth_success);
600: dispatch_set(SSH2_MSG_USERAUTH_FAILURE, &input_userauth_failure);
1.35 markus 601: dispatch_set(SSH2_MSG_USERAUTH_BANNER, &input_userauth_banner);
1.20 markus 602: dispatch_run(DISPATCH_BLOCK, &authctxt.success, &authctxt); /* loop until success */
603:
604: if (authctxt.agent != NULL)
605: ssh_close_authentication_connection(authctxt.agent);
606:
1.34 markus 607: debug("ssh-userauth2 successful: method %s", authctxt.method->name);
1.20 markus 608: }
609: void
1.51 markus 610: userauth(Authctxt *authctxt, char *authlist)
611: {
612: if (authlist == NULL) {
613: authlist = authctxt->authlist;
614: } else {
615: if (authctxt->authlist)
616: xfree(authctxt->authlist);
617: authctxt->authlist = authlist;
618: }
619: for (;;) {
620: Authmethod *method = authmethod_get(authlist);
621: if (method == NULL)
622: fatal("Permission denied (%s).", authlist);
623: authctxt->method = method;
624: if (method->userauth(authctxt) != 0) {
625: debug2("we sent a %s packet, wait for reply", method->name);
626: break;
627: } else {
628: debug2("we did not send a packet, disable method");
629: method->enabled = NULL;
630: }
631: }
632: }
633: void
1.20 markus 634: input_userauth_error(int type, int plen, void *ctxt)
635: {
1.35 markus 636: fatal("input_userauth_error: bad message during authentication: "
637: "type %d", type);
638: }
639: void
640: input_userauth_banner(int type, int plen, void *ctxt)
641: {
642: char *msg, *lang;
643: debug3("input_userauth_banner");
644: msg = packet_get_string(NULL);
645: lang = packet_get_string(NULL);
646: fprintf(stderr, "%s", msg);
647: xfree(msg);
648: xfree(lang);
1.20 markus 649: }
650: void
651: input_userauth_success(int type, int plen, void *ctxt)
652: {
653: Authctxt *authctxt = ctxt;
654: if (authctxt == NULL)
655: fatal("input_userauth_success: no authentication context");
1.51 markus 656: if (authctxt->authlist)
657: xfree(authctxt->authlist);
658: clear_auth_state(authctxt);
1.20 markus 659: authctxt->success = 1; /* break out */
660: }
661: void
662: input_userauth_failure(int type, int plen, void *ctxt)
663: {
664: Authctxt *authctxt = ctxt;
665: char *authlist = NULL;
666: int partial;
667:
668: if (authctxt == NULL)
669: fatal("input_userauth_failure: no authentication context");
670:
1.23 markus 671: authlist = packet_get_string(NULL);
1.20 markus 672: partial = packet_get_char();
673: packet_done();
674:
675: if (partial != 0)
1.45 markus 676: log("Authenticated with partial success.");
1.20 markus 677: debug("authentications that can continue: %s", authlist);
678:
1.51 markus 679: clear_auth_state(authctxt);
680: userauth(authctxt, authlist);
681: }
682: void
683: input_userauth_pk_ok(int type, int plen, void *ctxt)
684: {
685: Authctxt *authctxt = ctxt;
686: Key *key = NULL;
687: Buffer b;
688: int alen, blen, pktype, sent = 0;
1.54 markus 689: char *pkalg, *pkblob, *fp;
1.51 markus 690:
691: if (authctxt == NULL)
692: fatal("input_userauth_pk_ok: no authentication context");
693: if (datafellows & SSH_BUG_PKOK) {
694: /* this is similar to SSH_BUG_PKAUTH */
695: debug2("input_userauth_pk_ok: SSH_BUG_PKOK");
696: pkblob = packet_get_string(&blen);
697: buffer_init(&b);
698: buffer_append(&b, pkblob, blen);
699: pkalg = buffer_get_string(&b, &alen);
700: buffer_free(&b);
701: } else {
702: pkalg = packet_get_string(&alen);
703: pkblob = packet_get_string(&blen);
704: }
705: packet_done();
706:
707: debug("input_userauth_pk_ok: pkalg %s blen %d lastkey %p hint %d",
708: pkalg, blen, authctxt->last_key, authctxt->last_key_hint);
709:
710: do {
711: if (authctxt->last_key == NULL ||
712: authctxt->last_key_sign == NULL) {
713: debug("no last key or no sign cb");
714: break;
715: }
716: if ((pktype = key_type_from_name(pkalg)) == KEY_UNSPEC) {
717: debug("unknown pkalg %s", pkalg);
718: break;
719: }
720: if ((key = key_from_blob(pkblob, blen)) == NULL) {
721: debug("no key from blob. pkalg %s", pkalg);
722: break;
723: }
1.54 markus 724: fp = key_fingerprint(key, SSH_FP_MD5, SSH_FP_HEX);
725: debug2("input_userauth_pk_ok: fp %s", fp);
726: xfree(fp);
1.51 markus 727: if (!key_equal(key, authctxt->last_key)) {
728: debug("key != last_key");
1.20 markus 729: break;
730: }
1.51 markus 731: sent = sign_and_send_pubkey(authctxt, key,
732: authctxt->last_key_sign);
733: } while(0);
734:
735: if (key != NULL)
736: key_free(key);
737: xfree(pkalg);
738: xfree(pkblob);
739:
740: /* unregister */
741: clear_auth_state(authctxt);
742: dispatch_set(SSH2_MSG_USERAUTH_PK_OK, NULL);
743:
744: /* try another method if we did not send a packet*/
745: if (sent == 0)
746: userauth(authctxt, NULL);
747:
1.20 markus 748: }
749:
1.1 markus 750: int
1.23 markus 751: userauth_none(Authctxt *authctxt)
752: {
753: /* initial userauth request */
754: packet_start(SSH2_MSG_USERAUTH_REQUEST);
755: packet_put_cstring(authctxt->server_user);
756: packet_put_cstring(authctxt->service);
757: packet_put_cstring(authctxt->method->name);
758: packet_send();
759: return 1;
760: }
761:
762: int
1.20 markus 763: userauth_passwd(Authctxt *authctxt)
1.1 markus 764: {
1.6 markus 765: static int attempt = 0;
1.1 markus 766: char prompt[80];
767: char *password;
1.6 markus 768:
1.13 todd 769: if (attempt++ >= options.number_of_password_prompts)
1.6 markus 770: return 0;
1.13 todd 771:
772: if(attempt != 1)
773: error("Permission denied, please try again.");
1.1 markus 774:
1.43 itojun 775: snprintf(prompt, sizeof(prompt), "%.30s@%.128s's password: ",
1.20 markus 776: authctxt->server_user, authctxt->host);
1.1 markus 777: password = read_passphrase(prompt, 0);
778: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1.20 markus 779: packet_put_cstring(authctxt->server_user);
780: packet_put_cstring(authctxt->service);
1.23 markus 781: packet_put_cstring(authctxt->method->name);
1.1 markus 782: packet_put_char(0);
1.49 markus 783: packet_put_cstring(password);
1.1 markus 784: memset(password, 0, strlen(password));
785: xfree(password);
1.49 markus 786: packet_inject_ignore(64);
1.1 markus 787: packet_send();
788: return 1;
789: }
790:
1.51 markus 791: void
792: clear_auth_state(Authctxt *authctxt)
793: {
794: /* XXX clear authentication state */
795: if (authctxt->last_key != NULL && authctxt->last_key_hint == -1) {
796: debug3("clear_auth_state: key_free %p", authctxt->last_key);
797: key_free(authctxt->last_key);
798: }
799: authctxt->last_key = NULL;
800: authctxt->last_key_hint = -2;
801: authctxt->last_key_sign = NULL;
802: }
803:
1.17 markus 804: int
1.20 markus 805: sign_and_send_pubkey(Authctxt *authctxt, Key *k, sign_cb_fn *sign_callback)
1.1 markus 806: {
807: Buffer b;
1.32 markus 808: u_char *blob, *signature;
1.1 markus 809: int bloblen, slen;
1.14 markus 810: int skip = 0;
1.17 markus 811: int ret = -1;
1.23 markus 812: int have_sig = 1;
1.1 markus 813:
1.30 markus 814: debug3("sign_and_send_pubkey");
1.51 markus 815:
1.28 markus 816: if (key_to_blob(k, &blob, &bloblen) == 0) {
817: /* we cannot handle this key */
1.30 markus 818: debug3("sign_and_send_pubkey: cannot handle key");
1.28 markus 819: return 0;
820: }
1.1 markus 821: /* data to be signed */
822: buffer_init(&b);
1.26 markus 823: if (datafellows & SSH_OLD_SESSIONID) {
824: buffer_append(&b, session_id2, session_id2_len);
1.41 stevesk 825: skip = session_id2_len;
1.26 markus 826: } else {
1.14 markus 827: buffer_put_string(&b, session_id2, session_id2_len);
828: skip = buffer_len(&b);
829: }
1.1 markus 830: buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
1.20 markus 831: buffer_put_cstring(&b, authctxt->server_user);
1.10 markus 832: buffer_put_cstring(&b,
1.30 markus 833: datafellows & SSH_BUG_PKSERVICE ?
1.10 markus 834: "ssh-userauth" :
1.20 markus 835: authctxt->service);
1.30 markus 836: if (datafellows & SSH_BUG_PKAUTH) {
837: buffer_put_char(&b, have_sig);
838: } else {
839: buffer_put_cstring(&b, authctxt->method->name);
840: buffer_put_char(&b, have_sig);
1.41 stevesk 841: buffer_put_cstring(&b, key_ssh_name(k));
1.30 markus 842: }
1.1 markus 843: buffer_put_string(&b, blob, bloblen);
844:
845: /* generate signature */
1.51 markus 846: ret = (*sign_callback)(authctxt, k, &signature, &slen,
847: buffer_ptr(&b), buffer_len(&b));
1.17 markus 848: if (ret == -1) {
849: xfree(blob);
850: buffer_free(&b);
851: return 0;
852: }
1.28 markus 853: #ifdef DEBUG_PK
1.1 markus 854: buffer_dump(&b);
855: #endif
1.30 markus 856: if (datafellows & SSH_BUG_PKSERVICE) {
1.10 markus 857: buffer_clear(&b);
858: buffer_append(&b, session_id2, session_id2_len);
1.51 markus 859: skip = session_id2_len;
1.10 markus 860: buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
1.20 markus 861: buffer_put_cstring(&b, authctxt->server_user);
862: buffer_put_cstring(&b, authctxt->service);
1.23 markus 863: buffer_put_cstring(&b, authctxt->method->name);
864: buffer_put_char(&b, have_sig);
1.30 markus 865: if (!(datafellows & SSH_BUG_PKAUTH))
1.41 stevesk 866: buffer_put_cstring(&b, key_ssh_name(k));
1.10 markus 867: buffer_put_string(&b, blob, bloblen);
868: }
869: xfree(blob);
1.51 markus 870:
1.1 markus 871: /* append signature */
872: buffer_put_string(&b, signature, slen);
873: xfree(signature);
874:
875: /* skip session id and packet type */
1.14 markus 876: if (buffer_len(&b) < skip + 1)
1.20 markus 877: fatal("userauth_pubkey: internal error");
1.14 markus 878: buffer_consume(&b, skip + 1);
1.1 markus 879:
880: /* put remaining data from buffer into packet */
881: packet_start(SSH2_MSG_USERAUTH_REQUEST);
882: packet_put_raw(buffer_ptr(&b), buffer_len(&b));
883: buffer_free(&b);
884: packet_send();
1.17 markus 885:
886: return 1;
1.16 markus 887: }
888:
1.51 markus 889: int
890: send_pubkey_test(Authctxt *authctxt, Key *k, sign_cb_fn *sign_callback,
891: int hint)
1.20 markus 892: {
1.51 markus 893: u_char *blob;
894: int bloblen, have_sig = 0;
1.20 markus 895:
1.51 markus 896: debug3("send_pubkey_test");
1.16 markus 897:
1.51 markus 898: if (key_to_blob(k, &blob, &bloblen) == 0) {
899: /* we cannot handle this key */
900: debug3("send_pubkey_test: cannot handle key");
1.16 markus 901: return 0;
902: }
1.51 markus 903: /* register callback for USERAUTH_PK_OK message */
904: authctxt->last_key_sign = sign_callback;
905: authctxt->last_key_hint = hint;
906: authctxt->last_key = k;
907: dispatch_set(SSH2_MSG_USERAUTH_PK_OK, &input_userauth_pk_ok);
908:
909: packet_start(SSH2_MSG_USERAUTH_REQUEST);
910: packet_put_cstring(authctxt->server_user);
911: packet_put_cstring(authctxt->service);
912: packet_put_cstring(authctxt->method->name);
913: packet_put_char(have_sig);
914: if (!(datafellows & SSH_BUG_PKAUTH))
915: packet_put_cstring(key_ssh_name(k));
916: packet_put_string(blob, bloblen);
917: xfree(blob);
918: packet_send();
919: return 1;
920: }
921:
922: Key *
923: load_identity_file(char *filename)
924: {
925: Key *private;
926: char prompt[300], *passphrase;
1.56 markus 927: int quit, i;
1.52 markus 928: struct stat st;
1.16 markus 929:
1.52 markus 930: if (stat(filename, &st) < 0) {
931: debug3("no such identity: %s", filename);
932: return NULL;
933: }
1.56 markus 934: private = key_load_private_type(KEY_UNSPEC, filename, "", NULL);
935: if (private == NULL) {
936: if (options.batch_mode)
1.51 markus 937: return NULL;
1.16 markus 938: snprintf(prompt, sizeof prompt,
1.28 markus 939: "Enter passphrase for key '%.100s': ", filename);
1.20 markus 940: for (i = 0; i < options.number_of_password_prompts; i++) {
941: passphrase = read_passphrase(prompt, 0);
942: if (strcmp(passphrase, "") != 0) {
1.56 markus 943: private = key_load_private_type(KEY_UNSPEC, filename,
944: passphrase, NULL);
1.51 markus 945: quit = 0;
1.20 markus 946: } else {
947: debug2("no passphrase given, try next key");
1.51 markus 948: quit = 1;
1.20 markus 949: }
950: memset(passphrase, 0, strlen(passphrase));
951: xfree(passphrase);
1.56 markus 952: if (private != NULL || quit)
1.20 markus 953: break;
954: debug2("bad passphrase given, try again...");
1.16 markus 955: }
956: }
1.51 markus 957: return private;
958: }
959:
960: int
961: identity_sign_cb(Authctxt *authctxt, Key *key, u_char **sigp, int *lenp,
962: u_char *data, int datalen)
963: {
964: Key *private;
965: int idx, ret;
966:
967: idx = authctxt->last_key_hint;
968: if (idx < 0)
969: return -1;
970: private = load_identity_file(options.identity_files[idx]);
971: if (private == NULL)
972: return -1;
973: ret = key_sign(private, sigp, lenp, data, datalen);
974: key_free(private);
1.17 markus 975: return ret;
976: }
977:
1.32 markus 978: int agent_sign_cb(Authctxt *authctxt, Key *key, u_char **sigp, int *lenp,
979: u_char *data, int datalen)
1.17 markus 980: {
1.20 markus 981: return ssh_agent_sign(authctxt->agent, key, sigp, lenp, data, datalen);
1.17 markus 982: }
983:
1.51 markus 984: int key_sign_cb(Authctxt *authctxt, Key *key, u_char **sigp, int *lenp,
985: u_char *data, int datalen)
986: {
987: return key_sign(key, sigp, lenp, data, datalen);
988: }
989:
1.17 markus 990: int
1.20 markus 991: userauth_pubkey_agent(Authctxt *authctxt)
1.17 markus 992: {
993: static int called = 0;
1.28 markus 994: int ret = 0;
1.17 markus 995: char *comment;
996: Key *k;
997:
998: if (called == 0) {
1.28 markus 999: if (ssh_get_num_identities(authctxt->agent, 2) == 0)
1000: debug2("userauth_pubkey_agent: no keys at all");
1.20 markus 1001: called = 1;
1.17 markus 1002: }
1.28 markus 1003: k = ssh_get_next_identity(authctxt->agent, &comment, 2);
1.20 markus 1004: if (k == NULL) {
1.28 markus 1005: debug2("userauth_pubkey_agent: no more keys");
1006: } else {
1.51 markus 1007: debug("userauth_pubkey_agent: testing agent key %s", comment);
1.28 markus 1008: xfree(comment);
1.51 markus 1009: ret = send_pubkey_test(authctxt, k, agent_sign_cb, -1);
1010: if (ret == 0)
1011: key_free(k);
1.20 markus 1012: }
1.28 markus 1013: if (ret == 0)
1014: debug2("userauth_pubkey_agent: no message sent");
1.17 markus 1015: return ret;
1.1 markus 1016: }
1017:
1.20 markus 1018: int
1019: userauth_pubkey(Authctxt *authctxt)
1020: {
1021: static int idx = 0;
1022: int sent = 0;
1.51 markus 1023: Key *key;
1024: char *filename;
1.20 markus 1025:
1.28 markus 1026: if (authctxt->agent != NULL) {
1027: do {
1028: sent = userauth_pubkey_agent(authctxt);
1029: } while(!sent && authctxt->agent->howmany > 0);
1030: }
1031: while (!sent && idx < options.num_identity_files) {
1.51 markus 1032: key = options.identity_keys[idx];
1033: filename = options.identity_files[idx];
1034: if (key == NULL) {
1035: debug("try privkey: %s", filename);
1036: key = load_identity_file(filename);
1037: if (key != NULL) {
1038: sent = sign_and_send_pubkey(authctxt, key,
1039: key_sign_cb);
1040: key_free(key);
1041: }
1042: } else if (key->type != KEY_RSA1) {
1043: debug("try pubkey: %s", filename);
1044: sent = send_pubkey_test(authctxt, key,
1045: identity_sign_cb, idx);
1046: }
1.28 markus 1047: idx++;
1048: }
1.20 markus 1049: return sent;
1050: }
1051:
1.23 markus 1052: /*
1053: * Send userauth request message specifying keyboard-interactive method.
1054: */
1055: int
1056: userauth_kbdint(Authctxt *authctxt)
1057: {
1058: static int attempt = 0;
1059:
1060: if (attempt++ >= options.number_of_password_prompts)
1061: return 0;
1062:
1063: debug2("userauth_kbdint");
1064: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1065: packet_put_cstring(authctxt->server_user);
1066: packet_put_cstring(authctxt->service);
1067: packet_put_cstring(authctxt->method->name);
1068: packet_put_cstring(""); /* lang */
1069: packet_put_cstring(options.kbd_interactive_devices ?
1070: options.kbd_interactive_devices : "");
1071: packet_send();
1072:
1073: dispatch_set(SSH2_MSG_USERAUTH_INFO_REQUEST, &input_userauth_info_req);
1074: return 1;
1075: }
1076:
1077: /*
1.46 markus 1078: * parse INFO_REQUEST, prompt user and send INFO_RESPONSE
1.23 markus 1079: */
1080: void
1081: input_userauth_info_req(int type, int plen, void *ctxt)
1082: {
1083: Authctxt *authctxt = ctxt;
1.46 markus 1084: char *name, *inst, *lang, *prompt, *response;
1.32 markus 1085: u_int num_prompts, i;
1.23 markus 1086: int echo = 0;
1087:
1088: debug2("input_userauth_info_req");
1089:
1090: if (authctxt == NULL)
1091: fatal("input_userauth_info_req: no authentication context");
1092:
1093: name = packet_get_string(NULL);
1094: inst = packet_get_string(NULL);
1095: lang = packet_get_string(NULL);
1096: if (strlen(name) > 0)
1097: cli_mesg(name);
1098: if (strlen(inst) > 0)
1099: cli_mesg(inst);
1.46 markus 1100: xfree(name);
1.23 markus 1101: xfree(inst);
1.46 markus 1102: xfree(lang);
1.23 markus 1103:
1104: num_prompts = packet_get_int();
1105: /*
1106: * Begin to build info response packet based on prompts requested.
1107: * We commit to providing the correct number of responses, so if
1108: * further on we run into a problem that prevents this, we have to
1109: * be sure and clean this up and send a correct error response.
1110: */
1111: packet_start(SSH2_MSG_USERAUTH_INFO_RESPONSE);
1112: packet_put_int(num_prompts);
1113:
1114: for (i = 0; i < num_prompts; i++) {
1115: prompt = packet_get_string(NULL);
1116: echo = packet_get_char();
1117:
1118: response = cli_prompt(prompt, echo);
1119:
1.49 markus 1120: packet_put_cstring(response);
1.23 markus 1121: memset(response, 0, strlen(response));
1122: xfree(response);
1123: xfree(prompt);
1124: }
1125: packet_done(); /* done with parsing incoming message. */
1126:
1.49 markus 1127: packet_inject_ignore(64);
1.23 markus 1128: packet_send();
1129: }
1.20 markus 1130:
1131: /* find auth method */
1132:
1133: /*
1134: * given auth method name, if configurable options permit this method fill
1135: * in auth_ident field and return true, otherwise return false.
1136: */
1137: int
1138: authmethod_is_enabled(Authmethod *method)
1139: {
1140: if (method == NULL)
1141: return 0;
1142: /* return false if options indicate this method is disabled */
1143: if (method->enabled == NULL || *method->enabled == 0)
1144: return 0;
1145: /* return false if batch mode is enabled but method needs interactive mode */
1146: if (method->batch_flag != NULL && *method->batch_flag != 0)
1147: return 0;
1148: return 1;
1149: }
1150:
1151: Authmethod *
1152: authmethod_lookup(const char *name)
1.1 markus 1153: {
1.20 markus 1154: Authmethod *method = NULL;
1155: if (name != NULL)
1156: for (method = authmethods; method->name != NULL; method++)
1157: if (strcmp(name, method->name) == 0)
1158: return method;
1159: debug2("Unrecognized authentication method name: %s", name ? name : "NULL");
1160: return NULL;
1161: }
1.1 markus 1162:
1.53 markus 1163: /* XXX internal state */
1164: static Authmethod *current = NULL;
1165: static char *supported = NULL;
1166: static char *preferred = NULL;
1.20 markus 1167: /*
1168: * Given the authentication method list sent by the server, return the
1169: * next method we should try. If the server initially sends a nil list,
1.53 markus 1170: * use a built-in default list.
1.41 stevesk 1171: */
1.20 markus 1172: Authmethod *
1173: authmethod_get(char *authlist)
1174: {
1.53 markus 1175:
1176: char *name = NULL;
1177: int next;
1.41 stevesk 1178:
1.20 markus 1179: /* Use a suitable default if we're passed a nil list. */
1180: if (authlist == NULL || strlen(authlist) == 0)
1.53 markus 1181: authlist = options.preferred_authentications;
1.20 markus 1182:
1.53 markus 1183: if (supported == NULL || strcmp(authlist, supported) != 0) {
1184: debug3("start over, passed a different list %s", authlist);
1185: if (supported != NULL)
1186: xfree(supported);
1187: supported = xstrdup(authlist);
1188: preferred = options.preferred_authentications;
1189: debug3("preferred %s", preferred);
1190: current = NULL;
1191: } else if (current != NULL && authmethod_is_enabled(current))
1192: return current;
1.20 markus 1193:
1.53 markus 1194: for (;;) {
1195: if ((name = match_list(preferred, supported, &next)) == NULL) {
1196: debug("no more auth methods to try");
1197: current = NULL;
1198: return NULL;
1199: }
1200: preferred += next;
1.23 markus 1201: debug3("authmethod_lookup %s", name);
1.53 markus 1202: debug3("remaining preferred: %s", preferred);
1203: if ((current = authmethod_lookup(name)) != NULL &&
1204: authmethod_is_enabled(current)) {
1.23 markus 1205: debug3("authmethod_is_enabled %s", name);
1.53 markus 1206: debug("next auth method to try is %s", name);
1207: return current;
1.23 markus 1208: }
1.1 markus 1209: }
1.53 markus 1210: }
1.1 markus 1211:
1.27 provos 1212:
1.53 markus 1213: #define DELIM ","
1214: char *
1215: authmethods_get(void)
1216: {
1217: Authmethod *method = NULL;
1218: char buf[1024];
1.27 provos 1219:
1.53 markus 1220: buf[0] = '\0';
1221: for (method = authmethods; method->name != NULL; method++) {
1222: if (authmethod_is_enabled(method)) {
1223: if (buf[0] != '\0')
1224: strlcat(buf, DELIM, sizeof buf);
1225: strlcat(buf, method->name, sizeof buf);
1226: }
1227: }
1228: return xstrdup(buf);
1.1 markus 1229: }
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