Annotation of src/usr.bin/ssh/sshconnect2.c, Revision 1.219
1.219 ! markus 1: /* $OpenBSD: sshconnect2.c,v 1.218 2015/01/19 20:07:45 markus Exp $ */
1.1 markus 2: /*
3: * Copyright (c) 2000 Markus Friedl. All rights reserved.
1.170 djm 4: * Copyright (c) 2008 Damien Miller. All rights reserved.
1.1 markus 5: *
6: * Redistribution and use in source and binary forms, with or without
7: * modification, are permitted provided that the following conditions
8: * are met:
9: * 1. Redistributions of source code must retain the above copyright
10: * notice, this list of conditions and the following disclaimer.
11: * 2. Redistributions in binary form must reproduce the above copyright
12: * notice, this list of conditions and the following disclaimer in the
13: * documentation and/or other materials provided with the distribution.
14: *
15: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25: */
26:
1.145 stevesk 27: #include <sys/types.h>
1.160 deraadt 28: #include <sys/socket.h>
1.145 stevesk 29: #include <sys/wait.h>
1.144 stevesk 30: #include <sys/queue.h>
1.146 stevesk 31: #include <sys/stat.h>
1.156 stevesk 32:
33: #include <errno.h>
1.174 dtucker 34: #include <fcntl.h>
1.164 jolan 35: #include <netdb.h>
1.159 stevesk 36: #include <stdio.h>
1.158 stevesk 37: #include <string.h>
1.160 deraadt 38: #include <signal.h>
39: #include <pwd.h>
1.157 stevesk 40: #include <unistd.h>
1.166 djm 41: #include <vis.h>
1.1 markus 42:
1.160 deraadt 43: #include "xmalloc.h"
1.1 markus 44: #include "ssh.h"
1.37 markus 45: #include "ssh2.h"
1.1 markus 46: #include "buffer.h"
47: #include "packet.h"
48: #include "compat.h"
1.37 markus 49: #include "cipher.h"
1.160 deraadt 50: #include "key.h"
1.1 markus 51: #include "kex.h"
52: #include "myproposal.h"
53: #include "sshconnect.h"
54: #include "authfile.h"
1.57 provos 55: #include "dh.h"
1.17 markus 56: #include "authfd.h"
1.37 markus 57: #include "log.h"
1.210 millert 58: #include "misc.h"
1.37 markus 59: #include "readconf.h"
1.53 markus 60: #include "match.h"
1.61 markus 61: #include "dispatch.h"
1.68 markus 62: #include "canohost.h"
1.100 markus 63: #include "msg.h"
64: #include "pathnames.h"
1.154 markus 65: #include "uidswap.h"
1.186 djm 66: #include "hostfile.h"
1.214 djm 67: #include "ssherr.h"
1.22 provos 68:
1.121 markus 69: #ifdef GSSAPI
70: #include "ssh-gss.h"
71: #endif
72:
1.1 markus 73: /* import */
74: extern char *client_version_string;
75: extern char *server_version_string;
76: extern Options options;
77:
78: /*
79: * SSH2 key exchange
80: */
81:
1.32 markus 82: u_char *session_id2 = NULL;
1.120 markus 83: u_int session_id2_len = 0;
1.1 markus 84:
1.61 markus 85: char *xxx_host;
86: struct sockaddr *xxx_hostaddr;
87:
1.76 itojun 88: static int
1.219 ! markus 89: verify_host_key_callback(Key *hostkey, struct ssh *ssh)
1.61 markus 90: {
1.75 markus 91: if (verify_host_key(xxx_host, xxx_hostaddr, hostkey) == -1)
1.83 markus 92: fatal("Host key verification failed.");
1.61 markus 93: return 0;
94: }
95:
1.186 djm 96: static char *
97: order_hostkeyalgs(char *host, struct sockaddr *hostaddr, u_short port)
98: {
99: char *oavail, *avail, *first, *last, *alg, *hostname, *ret;
100: size_t maxlen;
101: struct hostkeys *hostkeys;
102: int ktype;
1.188 djm 103: u_int i;
1.186 djm 104:
105: /* Find all hostkeys for this hostname */
106: get_hostfile_hostname_ipaddr(host, hostaddr, port, &hostname, NULL);
107: hostkeys = init_hostkeys();
1.188 djm 108: for (i = 0; i < options.num_user_hostfiles; i++)
109: load_hostkeys(hostkeys, hostname, options.user_hostfiles[i]);
110: for (i = 0; i < options.num_system_hostfiles; i++)
111: load_hostkeys(hostkeys, hostname, options.system_hostfiles[i]);
1.186 djm 112:
113: oavail = avail = xstrdup(KEX_DEFAULT_PK_ALG);
114: maxlen = strlen(avail) + 1;
115: first = xmalloc(maxlen);
116: last = xmalloc(maxlen);
117: *first = *last = '\0';
118:
119: #define ALG_APPEND(to, from) \
120: do { \
121: if (*to != '\0') \
122: strlcat(to, ",", maxlen); \
123: strlcat(to, from, maxlen); \
124: } while (0)
125:
126: while ((alg = strsep(&avail, ",")) && *alg != '\0') {
1.214 djm 127: if ((ktype = sshkey_type_from_name(alg)) == KEY_UNSPEC)
1.186 djm 128: fatal("%s: unknown alg %s", __func__, alg);
129: if (lookup_key_in_hostkeys_by_type(hostkeys,
1.214 djm 130: sshkey_type_plain(ktype), NULL))
1.186 djm 131: ALG_APPEND(first, alg);
132: else
133: ALG_APPEND(last, alg);
134: }
135: #undef ALG_APPEND
1.216 djm 136: xasprintf(&ret, "%s%s%s", first,
137: (*first == '\0' || *last == '\0') ? "" : ",", last);
1.186 djm 138: if (*first != '\0')
139: debug3("%s: prefer hostkeyalgs: %s", __func__, first);
140:
1.197 djm 141: free(first);
142: free(last);
143: free(hostname);
144: free(oavail);
1.186 djm 145: free_hostkeys(hostkeys);
146:
147: return ret;
148: }
149:
1.1 markus 150: void
1.186 djm 151: ssh_kex2(char *host, struct sockaddr *hostaddr, u_short port)
1.22 provos 152: {
1.205 markus 153: char *myproposal[PROPOSAL_MAX] = { KEX_CLIENT };
1.219 ! markus 154: struct kex *kex;
1.61 markus 155:
156: xxx_host = host;
157: xxx_hostaddr = hostaddr;
1.22 provos 158:
1.29 markus 159: if (options.ciphers == (char *)-1) {
1.116 itojun 160: logit("No valid ciphers for protocol version 2 given, using defaults.");
1.29 markus 161: options.ciphers = NULL;
1.24 markus 162: }
1.22 provos 163: if (options.ciphers != NULL) {
164: myproposal[PROPOSAL_ENC_ALGS_CTOS] =
165: myproposal[PROPOSAL_ENC_ALGS_STOC] = options.ciphers;
166: }
1.60 stevesk 167: myproposal[PROPOSAL_ENC_ALGS_CTOS] =
168: compat_cipher_proposal(myproposal[PROPOSAL_ENC_ALGS_CTOS]);
169: myproposal[PROPOSAL_ENC_ALGS_STOC] =
170: compat_cipher_proposal(myproposal[PROPOSAL_ENC_ALGS_STOC]);
1.22 provos 171: if (options.compression) {
1.47 markus 172: myproposal[PROPOSAL_COMP_ALGS_CTOS] =
1.141 markus 173: myproposal[PROPOSAL_COMP_ALGS_STOC] = "zlib@openssh.com,zlib,none";
1.22 provos 174: } else {
1.47 markus 175: myproposal[PROPOSAL_COMP_ALGS_CTOS] =
1.141 markus 176: myproposal[PROPOSAL_COMP_ALGS_STOC] = "none,zlib@openssh.com,zlib";
1.47 markus 177: }
178: if (options.macs != NULL) {
179: myproposal[PROPOSAL_MAC_ALGS_CTOS] =
180: myproposal[PROPOSAL_MAC_ALGS_STOC] = options.macs;
1.22 provos 181: }
1.70 markus 182: if (options.hostkeyalgorithms != NULL)
1.88 deraadt 183: myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] =
1.200 djm 184: compat_pkalg_proposal(options.hostkeyalgorithms);
1.186 djm 185: else {
186: /* Prefer algorithms that we already have keys for */
187: myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] =
1.200 djm 188: compat_pkalg_proposal(
189: order_hostkeyalgs(host, hostaddr, port));
1.186 djm 190: }
1.185 djm 191: if (options.kex_algorithms != NULL)
192: myproposal[PROPOSAL_KEX_ALGS] = options.kex_algorithms;
1.206 djm 193: myproposal[PROPOSAL_KEX_ALGS] = compat_kex_proposal(
194: myproposal[PROPOSAL_KEX_ALGS]);
1.115 markus 195:
1.196 dtucker 196: if (options.rekey_limit || options.rekey_interval)
197: packet_set_rekey_limits((u_int32_t)options.rekey_limit,
198: (time_t)options.rekey_interval);
1.22 provos 199:
1.65 markus 200: /* start key exchange */
1.219 ! markus 201: kex_setup(active_state, myproposal);
! 202: kex = active_state->kex;
1.207 markus 203: #ifdef WITH_OPENSSL
1.111 markus 204: kex->kex[KEX_DH_GRP1_SHA1] = kexdh_client;
1.138 djm 205: kex->kex[KEX_DH_GRP14_SHA1] = kexdh_client;
1.111 markus 206: kex->kex[KEX_DH_GEX_SHA1] = kexgex_client;
1.147 djm 207: kex->kex[KEX_DH_GEX_SHA256] = kexgex_client;
1.184 djm 208: kex->kex[KEX_ECDH_SHA2] = kexecdh_client;
1.207 markus 209: #endif
1.199 markus 210: kex->kex[KEX_C25519_SHA256] = kexc25519_client;
1.61 markus 211: kex->client_version_string=client_version_string;
212: kex->server_version_string=server_version_string;
1.75 markus 213: kex->verify_host_key=&verify_host_key_callback;
1.22 provos 214:
1.219 ! markus 215: dispatch_run(DISPATCH_BLOCK, &kex->done, active_state);
1.173 andreas 216:
217: if (options.use_roaming && !kex->roaming) {
218: debug("Roaming not allowed by server");
219: options.use_roaming = 0;
220: }
1.62 markus 221:
222: session_id2 = kex->session_id;
223: session_id2_len = kex->session_id_len;
1.22 provos 224:
225: #ifdef DEBUG_KEXDH
226: /* send 1st encrypted/maced/compressed message */
227: packet_start(SSH2_MSG_IGNORE);
228: packet_put_cstring("markus");
229: packet_send();
230: packet_write_wait();
231: #endif
1.1 markus 232: }
1.11 markus 233:
1.1 markus 234: /*
235: * Authenticate user
236: */
1.20 markus 237:
1.214 djm 238: typedef struct cauthctxt Authctxt;
239: typedef struct cauthmethod Authmethod;
1.117 markus 240: typedef struct identity Identity;
241: typedef struct idlist Idlist;
1.20 markus 242:
1.117 markus 243: struct identity {
244: TAILQ_ENTRY(identity) next;
1.214 djm 245: int agent_fd; /* >=0 if agent supports key */
246: struct sshkey *key; /* public/private key */
1.117 markus 247: char *filename; /* comment for agent-only keys */
248: int tried;
249: int isprivate; /* key points to the private key */
1.191 dtucker 250: int userprovided;
1.117 markus 251: };
252: TAILQ_HEAD(idlist, identity);
1.20 markus 253:
1.214 djm 254: struct cauthctxt {
1.20 markus 255: const char *server_user;
1.68 markus 256: const char *local_user;
1.20 markus 257: const char *host;
258: const char *service;
1.214 djm 259: struct cauthmethod *method;
1.183 djm 260: sig_atomic_t success;
1.51 markus 261: char *authlist;
1.214 djm 262: int attempt;
1.68 markus 263: /* pubkey */
1.214 djm 264: struct idlist keys;
265: int agent_fd;
1.68 markus 266: /* hostbased */
1.100 markus 267: Sensitive *sensitive;
1.82 markus 268: /* kbd-interactive */
269: int info_req_seen;
1.121 markus 270: /* generic */
271: void *methoddata;
1.20 markus 272: };
1.214 djm 273:
274: struct cauthmethod {
1.20 markus 275: char *name; /* string to compare against server's list */
276: int (*userauth)(Authctxt *authctxt);
1.170 djm 277: void (*cleanup)(Authctxt *authctxt);
1.20 markus 278: int *enabled; /* flag in option struct that enables method */
279: int *batch_flag; /* flag in option struct that disables method */
280: };
281:
1.218 markus 282: int input_userauth_success(int, u_int32_t, void *);
283: int input_userauth_success_unexpected(int, u_int32_t, void *);
284: int input_userauth_failure(int, u_int32_t, void *);
285: int input_userauth_banner(int, u_int32_t, void *);
286: int input_userauth_error(int, u_int32_t, void *);
287: int input_userauth_info_req(int, u_int32_t, void *);
288: int input_userauth_pk_ok(int, u_int32_t, void *);
289: int input_userauth_passwd_changereq(int, u_int32_t, void *);
1.86 itojun 290:
291: int userauth_none(Authctxt *);
292: int userauth_pubkey(Authctxt *);
293: int userauth_passwd(Authctxt *);
294: int userauth_kbdint(Authctxt *);
295: int userauth_hostbased(Authctxt *);
1.20 markus 296:
1.121 markus 297: #ifdef GSSAPI
298: int userauth_gssapi(Authctxt *authctxt);
1.218 markus 299: int input_gssapi_response(int type, u_int32_t, void *);
300: int input_gssapi_token(int type, u_int32_t, void *);
301: int input_gssapi_hash(int type, u_int32_t, void *);
302: int input_gssapi_error(int, u_int32_t, void *);
303: int input_gssapi_errtok(int, u_int32_t, void *);
1.121 markus 304: #endif
305:
1.86 itojun 306: void userauth(Authctxt *, char *);
1.51 markus 307:
1.117 markus 308: static int sign_and_send_pubkey(Authctxt *, Identity *);
309: static void pubkey_prepare(Authctxt *);
310: static void pubkey_cleanup(Authctxt *);
1.191 dtucker 311: static Key *load_identity_file(char *, int);
1.76 itojun 312:
313: static Authmethod *authmethod_get(char *authlist);
314: static Authmethod *authmethod_lookup(const char *name);
315: static char *authmethods_get(void);
1.20 markus 316:
317: Authmethod authmethods[] = {
1.121 markus 318: #ifdef GSSAPI
1.132 markus 319: {"gssapi-with-mic",
1.121 markus 320: userauth_gssapi,
1.170 djm 321: NULL,
1.121 markus 322: &options.gss_authentication,
323: NULL},
324: #endif
1.81 markus 325: {"hostbased",
326: userauth_hostbased,
1.170 djm 327: NULL,
1.81 markus 328: &options.hostbased_authentication,
329: NULL},
1.20 markus 330: {"publickey",
331: userauth_pubkey,
1.170 djm 332: NULL,
1.28 markus 333: &options.pubkey_authentication,
1.20 markus 334: NULL},
1.81 markus 335: {"keyboard-interactive",
336: userauth_kbdint,
1.170 djm 337: NULL,
1.81 markus 338: &options.kbd_interactive_authentication,
339: &options.batch_mode},
1.20 markus 340: {"password",
341: userauth_passwd,
1.170 djm 342: NULL,
1.20 markus 343: &options.password_authentication,
1.23 markus 344: &options.batch_mode},
345: {"none",
346: userauth_none,
347: NULL,
1.170 djm 348: NULL,
1.23 markus 349: NULL},
1.170 djm 350: {NULL, NULL, NULL, NULL, NULL}
1.20 markus 351: };
352:
353: void
1.68 markus 354: ssh_userauth2(const char *local_user, const char *server_user, char *host,
1.100 markus 355: Sensitive *sensitive)
1.20 markus 356: {
357: Authctxt authctxt;
358: int type;
1.39 markus 359:
1.73 markus 360: if (options.challenge_response_authentication)
1.39 markus 361: options.kbd_interactive_authentication = 1;
1.20 markus 362:
363: packet_start(SSH2_MSG_SERVICE_REQUEST);
364: packet_put_cstring("ssh-userauth");
365: packet_send();
1.108 markus 366: debug("SSH2_MSG_SERVICE_REQUEST sent");
1.20 markus 367: packet_write_wait();
1.91 markus 368: type = packet_read();
1.108 markus 369: if (type != SSH2_MSG_SERVICE_ACCEPT)
370: fatal("Server denied authentication request: %d", type);
1.20 markus 371: if (packet_remaining() > 0) {
1.91 markus 372: char *reply = packet_get_string(NULL);
1.108 markus 373: debug2("service_accept: %s", reply);
1.197 djm 374: free(reply);
1.20 markus 375: } else {
1.109 markus 376: debug2("buggy server: service_accept w/o service");
1.20 markus 377: }
1.90 markus 378: packet_check_eom();
1.108 markus 379: debug("SSH2_MSG_SERVICE_ACCEPT received");
1.20 markus 380:
1.53 markus 381: if (options.preferred_authentications == NULL)
382: options.preferred_authentications = authmethods_get();
383:
1.20 markus 384: /* setup authentication context */
1.82 markus 385: memset(&authctxt, 0, sizeof(authctxt));
1.117 markus 386: pubkey_prepare(&authctxt);
1.20 markus 387: authctxt.server_user = server_user;
1.68 markus 388: authctxt.local_user = local_user;
1.20 markus 389: authctxt.host = host;
390: authctxt.service = "ssh-connection"; /* service name */
391: authctxt.success = 0;
1.23 markus 392: authctxt.method = authmethod_lookup("none");
1.51 markus 393: authctxt.authlist = NULL;
1.121 markus 394: authctxt.methoddata = NULL;
1.100 markus 395: authctxt.sensitive = sensitive;
1.82 markus 396: authctxt.info_req_seen = 0;
1.215 djm 397: authctxt.agent_fd = -1;
1.23 markus 398: if (authctxt.method == NULL)
399: fatal("ssh_userauth2: internal error: cannot send userauth none request");
1.20 markus 400:
401: /* initial userauth request */
1.23 markus 402: userauth_none(&authctxt);
1.20 markus 403:
1.65 markus 404: dispatch_init(&input_userauth_error);
1.20 markus 405: dispatch_set(SSH2_MSG_USERAUTH_SUCCESS, &input_userauth_success);
406: dispatch_set(SSH2_MSG_USERAUTH_FAILURE, &input_userauth_failure);
1.35 markus 407: dispatch_set(SSH2_MSG_USERAUTH_BANNER, &input_userauth_banner);
1.20 markus 408: dispatch_run(DISPATCH_BLOCK, &authctxt.success, &authctxt); /* loop until success */
409:
1.117 markus 410: pubkey_cleanup(&authctxt);
1.119 markus 411: dispatch_range(SSH2_MSG_USERAUTH_MIN, SSH2_MSG_USERAUTH_MAX, NULL);
412:
1.109 markus 413: debug("Authentication succeeded (%s).", authctxt.method->name);
1.20 markus 414: }
1.119 markus 415:
1.20 markus 416: void
1.51 markus 417: userauth(Authctxt *authctxt, char *authlist)
418: {
1.170 djm 419: if (authctxt->method != NULL && authctxt->method->cleanup != NULL)
420: authctxt->method->cleanup(authctxt);
421:
1.197 djm 422: free(authctxt->methoddata);
423: authctxt->methoddata = NULL;
1.51 markus 424: if (authlist == NULL) {
425: authlist = authctxt->authlist;
426: } else {
1.197 djm 427: free(authctxt->authlist);
1.51 markus 428: authctxt->authlist = authlist;
429: }
430: for (;;) {
431: Authmethod *method = authmethod_get(authlist);
432: if (method == NULL)
433: fatal("Permission denied (%s).", authlist);
434: authctxt->method = method;
1.119 markus 435:
436: /* reset the per method handler */
437: dispatch_range(SSH2_MSG_USERAUTH_PER_METHOD_MIN,
438: SSH2_MSG_USERAUTH_PER_METHOD_MAX, NULL);
439:
440: /* and try new method */
1.51 markus 441: if (method->userauth(authctxt) != 0) {
442: debug2("we sent a %s packet, wait for reply", method->name);
443: break;
444: } else {
445: debug2("we did not send a packet, disable method");
446: method->enabled = NULL;
447: }
448: }
449: }
1.105 deraadt 450:
1.169 djm 451: /* ARGSUSED */
1.218 markus 452: int
1.92 markus 453: input_userauth_error(int type, u_int32_t seq, void *ctxt)
1.20 markus 454: {
1.35 markus 455: fatal("input_userauth_error: bad message during authentication: "
1.140 djm 456: "type %d", type);
1.218 markus 457: return 0;
1.35 markus 458: }
1.105 deraadt 459:
1.169 djm 460: /* ARGSUSED */
1.218 markus 461: int
1.92 markus 462: input_userauth_banner(int type, u_int32_t seq, void *ctxt)
1.35 markus 463: {
1.166 djm 464: char *msg, *raw, *lang;
465: u_int len;
1.126 deraadt 466:
1.35 markus 467: debug3("input_userauth_banner");
1.166 djm 468: raw = packet_get_string(&len);
1.35 markus 469: lang = packet_get_string(NULL);
1.167 markus 470: if (len > 0 && options.log_level >= SYSLOG_LEVEL_INFO) {
1.166 djm 471: if (len > 65536)
472: len = 65536;
1.168 deraadt 473: msg = xmalloc(len * 4 + 1); /* max expansion from strnvis() */
1.177 dtucker 474: strnvis(msg, raw, len * 4 + 1, VIS_SAFE|VIS_OCTAL|VIS_NOSLASH);
1.125 dtucker 475: fprintf(stderr, "%s", msg);
1.197 djm 476: free(msg);
1.166 djm 477: }
1.197 djm 478: free(raw);
479: free(lang);
1.218 markus 480: return 0;
1.20 markus 481: }
1.105 deraadt 482:
1.169 djm 483: /* ARGSUSED */
1.218 markus 484: int
1.92 markus 485: input_userauth_success(int type, u_int32_t seq, void *ctxt)
1.20 markus 486: {
487: Authctxt *authctxt = ctxt;
1.172 djm 488:
1.20 markus 489: if (authctxt == NULL)
490: fatal("input_userauth_success: no authentication context");
1.197 djm 491: free(authctxt->authlist);
492: authctxt->authlist = NULL;
1.172 djm 493: if (authctxt->method != NULL && authctxt->method->cleanup != NULL)
494: authctxt->method->cleanup(authctxt);
1.197 djm 495: free(authctxt->methoddata);
496: authctxt->methoddata = NULL;
1.20 markus 497: authctxt->success = 1; /* break out */
1.218 markus 498: return 0;
1.20 markus 499: }
1.105 deraadt 500:
1.218 markus 501: int
1.172 djm 502: input_userauth_success_unexpected(int type, u_int32_t seq, void *ctxt)
503: {
504: Authctxt *authctxt = ctxt;
505:
506: if (authctxt == NULL)
507: fatal("%s: no authentication context", __func__);
508:
509: fatal("Unexpected authentication success during %s.",
510: authctxt->method->name);
1.218 markus 511: return 0;
1.172 djm 512: }
513:
1.169 djm 514: /* ARGSUSED */
1.218 markus 515: int
1.92 markus 516: input_userauth_failure(int type, u_int32_t seq, void *ctxt)
1.20 markus 517: {
518: Authctxt *authctxt = ctxt;
519: char *authlist = NULL;
520: int partial;
521:
522: if (authctxt == NULL)
523: fatal("input_userauth_failure: no authentication context");
524:
1.23 markus 525: authlist = packet_get_string(NULL);
1.20 markus 526: partial = packet_get_char();
1.90 markus 527: packet_check_eom();
1.20 markus 528:
1.193 markus 529: if (partial != 0) {
1.116 itojun 530: logit("Authenticated with partial success.");
1.193 markus 531: /* reset state */
532: pubkey_cleanup(authctxt);
533: pubkey_prepare(authctxt);
534: }
1.109 markus 535: debug("Authentications that can continue: %s", authlist);
1.20 markus 536:
1.51 markus 537: userauth(authctxt, authlist);
1.218 markus 538: return 0;
1.51 markus 539: }
1.169 djm 540:
541: /* ARGSUSED */
1.218 markus 542: int
1.92 markus 543: input_userauth_pk_ok(int type, u_int32_t seq, void *ctxt)
1.51 markus 544: {
545: Authctxt *authctxt = ctxt;
546: Key *key = NULL;
1.117 markus 547: Identity *id = NULL;
1.51 markus 548: Buffer b;
1.96 markus 549: int pktype, sent = 0;
550: u_int alen, blen;
551: char *pkalg, *fp;
552: u_char *pkblob;
1.51 markus 553:
554: if (authctxt == NULL)
555: fatal("input_userauth_pk_ok: no authentication context");
556: if (datafellows & SSH_BUG_PKOK) {
557: /* this is similar to SSH_BUG_PKAUTH */
558: debug2("input_userauth_pk_ok: SSH_BUG_PKOK");
559: pkblob = packet_get_string(&blen);
560: buffer_init(&b);
561: buffer_append(&b, pkblob, blen);
562: pkalg = buffer_get_string(&b, &alen);
563: buffer_free(&b);
564: } else {
565: pkalg = packet_get_string(&alen);
566: pkblob = packet_get_string(&blen);
567: }
1.90 markus 568: packet_check_eom();
1.51 markus 569:
1.117 markus 570: debug("Server accepts key: pkalg %s blen %u", pkalg, blen);
1.51 markus 571:
1.117 markus 572: if ((pktype = key_type_from_name(pkalg)) == KEY_UNSPEC) {
573: debug("unknown pkalg %s", pkalg);
574: goto done;
575: }
576: if ((key = key_from_blob(pkblob, blen)) == NULL) {
577: debug("no key from blob. pkalg %s", pkalg);
578: goto done;
579: }
580: if (key->type != pktype) {
581: error("input_userauth_pk_ok: type mismatch "
582: "for decoded key (received %d, expected %d)",
583: key->type, pktype);
584: goto done;
585: }
1.214 djm 586: fp = sshkey_fingerprint(key, options.fingerprint_hash, SSH_FP_DEFAULT);
1.117 markus 587: debug2("input_userauth_pk_ok: fp %s", fp);
1.197 djm 588: free(fp);
1.117 markus 589:
1.127 markus 590: /*
591: * search keys in the reverse order, because last candidate has been
592: * moved to the end of the queue. this also avoids confusion by
593: * duplicate keys
594: */
1.136 henning 595: TAILQ_FOREACH_REVERSE(id, &authctxt->keys, idlist, next) {
1.117 markus 596: if (key_equal(key, id->key)) {
597: sent = sign_and_send_pubkey(authctxt, id);
1.51 markus 598: break;
599: }
1.117 markus 600: }
601: done:
1.51 markus 602: if (key != NULL)
603: key_free(key);
1.197 djm 604: free(pkalg);
605: free(pkblob);
1.51 markus 606:
1.106 deraadt 607: /* try another method if we did not send a packet */
1.51 markus 608: if (sent == 0)
609: userauth(authctxt, NULL);
1.218 markus 610: return 0;
1.20 markus 611: }
1.121 markus 612:
613: #ifdef GSSAPI
1.133 djm 614: int
1.121 markus 615: userauth_gssapi(Authctxt *authctxt)
616: {
617: Gssctxt *gssctxt = NULL;
1.128 avsm 618: static gss_OID_set gss_supported = NULL;
1.139 djm 619: static u_int mech = 0;
1.121 markus 620: OM_uint32 min;
621: int ok = 0;
622:
623: /* Try one GSSAPI method at a time, rather than sending them all at
624: * once. */
625:
1.128 avsm 626: if (gss_supported == NULL)
627: gss_indicate_mechs(&min, &gss_supported);
1.121 markus 628:
629: /* Check to see if the mechanism is usable before we offer it */
1.128 avsm 630: while (mech < gss_supported->count && !ok) {
1.121 markus 631: /* My DER encoding requires length<128 */
1.128 avsm 632: if (gss_supported->elements[mech].length < 128 &&
1.161 djm 633: ssh_gssapi_check_mechanism(&gssctxt,
634: &gss_supported->elements[mech], authctxt->host)) {
1.121 markus 635: ok = 1; /* Mechanism works */
636: } else {
637: mech++;
638: }
639: }
640:
1.161 djm 641: if (!ok)
1.139 djm 642: return 0;
1.121 markus 643:
644: authctxt->methoddata=(void *)gssctxt;
645:
646: packet_start(SSH2_MSG_USERAUTH_REQUEST);
647: packet_put_cstring(authctxt->server_user);
648: packet_put_cstring(authctxt->service);
649: packet_put_cstring(authctxt->method->name);
650:
651: packet_put_int(1);
652:
1.129 markus 653: packet_put_int((gss_supported->elements[mech].length) + 2);
654: packet_put_char(SSH_GSS_OIDTYPE);
655: packet_put_char(gss_supported->elements[mech].length);
656: packet_put_raw(gss_supported->elements[mech].elements,
657: gss_supported->elements[mech].length);
1.121 markus 658:
659: packet_send();
660:
661: dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_RESPONSE, &input_gssapi_response);
662: dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, &input_gssapi_token);
663: dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERROR, &input_gssapi_error);
664: dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK, &input_gssapi_errtok);
665:
666: mech++; /* Move along to next candidate */
667:
668: return 1;
669: }
670:
1.130 markus 671: static OM_uint32
672: process_gssapi_token(void *ctxt, gss_buffer_t recv_tok)
673: {
674: Authctxt *authctxt = ctxt;
675: Gssctxt *gssctxt = authctxt->methoddata;
676: gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
1.142 djm 677: gss_buffer_desc mic = GSS_C_EMPTY_BUFFER;
678: gss_buffer_desc gssbuf;
1.132 markus 679: OM_uint32 status, ms, flags;
680: Buffer b;
1.133 djm 681:
1.130 markus 682: status = ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
1.132 markus 683: recv_tok, &send_tok, &flags);
1.130 markus 684:
685: if (send_tok.length > 0) {
686: if (GSS_ERROR(status))
687: packet_start(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK);
688: else
689: packet_start(SSH2_MSG_USERAUTH_GSSAPI_TOKEN);
1.133 djm 690:
1.130 markus 691: packet_put_string(send_tok.value, send_tok.length);
692: packet_send();
693: gss_release_buffer(&ms, &send_tok);
694: }
1.133 djm 695:
1.130 markus 696: if (status == GSS_S_COMPLETE) {
1.132 markus 697: /* send either complete or MIC, depending on mechanism */
698: if (!(flags & GSS_C_INTEG_FLAG)) {
699: packet_start(SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE);
700: packet_send();
701: } else {
702: ssh_gssapi_buildmic(&b, authctxt->server_user,
703: authctxt->service, "gssapi-with-mic");
704:
705: gssbuf.value = buffer_ptr(&b);
706: gssbuf.length = buffer_len(&b);
1.133 djm 707:
1.132 markus 708: status = ssh_gssapi_sign(gssctxt, &gssbuf, &mic);
1.133 djm 709:
1.132 markus 710: if (!GSS_ERROR(status)) {
711: packet_start(SSH2_MSG_USERAUTH_GSSAPI_MIC);
712: packet_put_string(mic.value, mic.length);
1.133 djm 713:
1.132 markus 714: packet_send();
715: }
1.133 djm 716:
1.132 markus 717: buffer_free(&b);
718: gss_release_buffer(&ms, &mic);
1.133 djm 719: }
1.130 markus 720: }
1.133 djm 721:
1.130 markus 722: return status;
723: }
724:
1.169 djm 725: /* ARGSUSED */
1.121 markus 726: void
727: input_gssapi_response(int type, u_int32_t plen, void *ctxt)
728: {
729: Authctxt *authctxt = ctxt;
730: Gssctxt *gssctxt;
731: int oidlen;
732: char *oidv;
733:
734: if (authctxt == NULL)
735: fatal("input_gssapi_response: no authentication context");
736: gssctxt = authctxt->methoddata;
737:
738: /* Setup our OID */
739: oidv = packet_get_string(&oidlen);
740:
1.129 markus 741: if (oidlen <= 2 ||
742: oidv[0] != SSH_GSS_OIDTYPE ||
743: oidv[1] != oidlen - 2) {
1.197 djm 744: free(oidv);
1.129 markus 745: debug("Badly encoded mechanism OID received");
746: userauth(authctxt, NULL);
747: return;
1.121 markus 748: }
1.129 markus 749:
750: if (!ssh_gssapi_check_oid(gssctxt, oidv + 2, oidlen - 2))
751: fatal("Server returned different OID than expected");
1.121 markus 752:
753: packet_check_eom();
754:
1.197 djm 755: free(oidv);
1.121 markus 756:
1.130 markus 757: if (GSS_ERROR(process_gssapi_token(ctxt, GSS_C_NO_BUFFER))) {
1.121 markus 758: /* Start again with next method on list */
759: debug("Trying to start again");
760: userauth(authctxt, NULL);
761: return;
762: }
763: }
764:
1.169 djm 765: /* ARGSUSED */
1.121 markus 766: void
767: input_gssapi_token(int type, u_int32_t plen, void *ctxt)
768: {
769: Authctxt *authctxt = ctxt;
770: gss_buffer_desc recv_tok;
1.130 markus 771: OM_uint32 status;
1.121 markus 772: u_int slen;
773:
774: if (authctxt == NULL)
775: fatal("input_gssapi_response: no authentication context");
776:
777: recv_tok.value = packet_get_string(&slen);
778: recv_tok.length = slen; /* safe typecast */
779:
780: packet_check_eom();
781:
1.130 markus 782: status = process_gssapi_token(ctxt, &recv_tok);
1.121 markus 783:
1.197 djm 784: free(recv_tok.value);
1.121 markus 785:
786: if (GSS_ERROR(status)) {
787: /* Start again with the next method in the list */
788: userauth(authctxt, NULL);
789: return;
790: }
791: }
792:
1.169 djm 793: /* ARGSUSED */
1.121 markus 794: void
795: input_gssapi_errtok(int type, u_int32_t plen, void *ctxt)
796: {
797: Authctxt *authctxt = ctxt;
798: Gssctxt *gssctxt;
799: gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
800: gss_buffer_desc recv_tok;
1.194 djm 801: OM_uint32 ms;
1.123 deraadt 802: u_int len;
1.121 markus 803:
804: if (authctxt == NULL)
805: fatal("input_gssapi_response: no authentication context");
806: gssctxt = authctxt->methoddata;
807:
1.123 deraadt 808: recv_tok.value = packet_get_string(&len);
809: recv_tok.length = len;
1.121 markus 810:
811: packet_check_eom();
812:
813: /* Stick it into GSSAPI and see what it says */
1.194 djm 814: (void)ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
1.140 djm 815: &recv_tok, &send_tok, NULL);
1.121 markus 816:
1.197 djm 817: free(recv_tok.value);
1.121 markus 818: gss_release_buffer(&ms, &send_tok);
819:
820: /* Server will be returning a failed packet after this one */
821: }
822:
1.169 djm 823: /* ARGSUSED */
1.121 markus 824: void
825: input_gssapi_error(int type, u_int32_t plen, void *ctxt)
826: {
827: char *msg;
828: char *lang;
829:
1.194 djm 830: /* maj */(void)packet_get_int();
831: /* min */(void)packet_get_int();
1.121 markus 832: msg=packet_get_string(NULL);
833: lang=packet_get_string(NULL);
834:
835: packet_check_eom();
836:
1.143 stevesk 837: debug("Server GSSAPI Error:\n%s", msg);
1.197 djm 838: free(msg);
839: free(lang);
1.121 markus 840: }
841: #endif /* GSSAPI */
1.20 markus 842:
1.1 markus 843: int
1.23 markus 844: userauth_none(Authctxt *authctxt)
845: {
846: /* initial userauth request */
847: packet_start(SSH2_MSG_USERAUTH_REQUEST);
848: packet_put_cstring(authctxt->server_user);
849: packet_put_cstring(authctxt->service);
850: packet_put_cstring(authctxt->method->name);
851: packet_send();
852: return 1;
853: }
854:
855: int
1.20 markus 856: userauth_passwd(Authctxt *authctxt)
1.1 markus 857: {
1.6 markus 858: static int attempt = 0;
1.99 markus 859: char prompt[150];
1.1 markus 860: char *password;
1.175 dtucker 861: const char *host = options.host_key_alias ? options.host_key_alias :
862: authctxt->host;
1.6 markus 863:
1.13 todd 864: if (attempt++ >= options.number_of_password_prompts)
1.6 markus 865: return 0;
1.13 todd 866:
1.87 deraadt 867: if (attempt != 1)
1.13 todd 868: error("Permission denied, please try again.");
1.1 markus 869:
1.43 itojun 870: snprintf(prompt, sizeof(prompt), "%.30s@%.128s's password: ",
1.175 dtucker 871: authctxt->server_user, host);
1.1 markus 872: password = read_passphrase(prompt, 0);
873: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1.20 markus 874: packet_put_cstring(authctxt->server_user);
875: packet_put_cstring(authctxt->service);
1.23 markus 876: packet_put_cstring(authctxt->method->name);
1.1 markus 877: packet_put_char(0);
1.49 markus 878: packet_put_cstring(password);
1.204 djm 879: explicit_bzero(password, strlen(password));
1.197 djm 880: free(password);
1.85 markus 881: packet_add_padding(64);
1.1 markus 882: packet_send();
1.99 markus 883:
1.104 deraadt 884: dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
1.99 markus 885: &input_userauth_passwd_changereq);
886:
1.1 markus 887: return 1;
888: }
1.169 djm 889:
1.99 markus 890: /*
891: * parse PASSWD_CHANGEREQ, prompt user and send SSH2_MSG_USERAUTH_REQUEST
892: */
1.169 djm 893: /* ARGSUSED */
1.218 markus 894: int
1.153 djm 895: input_userauth_passwd_changereq(int type, u_int32_t seqnr, void *ctxt)
1.99 markus 896: {
897: Authctxt *authctxt = ctxt;
898: char *info, *lang, *password = NULL, *retype = NULL;
899: char prompt[150];
1.175 dtucker 900: const char *host = options.host_key_alias ? options.host_key_alias :
901: authctxt->host;
1.99 markus 902:
903: debug2("input_userauth_passwd_changereq");
904:
905: if (authctxt == NULL)
906: fatal("input_userauth_passwd_changereq: "
907: "no authentication context");
908:
909: info = packet_get_string(NULL);
910: lang = packet_get_string(NULL);
911: if (strlen(info) > 0)
1.116 itojun 912: logit("%s", info);
1.197 djm 913: free(info);
914: free(lang);
1.99 markus 915: packet_start(SSH2_MSG_USERAUTH_REQUEST);
916: packet_put_cstring(authctxt->server_user);
917: packet_put_cstring(authctxt->service);
918: packet_put_cstring(authctxt->method->name);
919: packet_put_char(1); /* additional info */
1.104 deraadt 920: snprintf(prompt, sizeof(prompt),
1.99 markus 921: "Enter %.30s@%.128s's old password: ",
1.175 dtucker 922: authctxt->server_user, host);
1.99 markus 923: password = read_passphrase(prompt, 0);
924: packet_put_cstring(password);
1.204 djm 925: explicit_bzero(password, strlen(password));
1.197 djm 926: free(password);
1.99 markus 927: password = NULL;
928: while (password == NULL) {
1.104 deraadt 929: snprintf(prompt, sizeof(prompt),
1.99 markus 930: "Enter %.30s@%.128s's new password: ",
1.175 dtucker 931: authctxt->server_user, host);
1.99 markus 932: password = read_passphrase(prompt, RP_ALLOW_EOF);
933: if (password == NULL) {
934: /* bail out */
1.218 markus 935: return 0;
1.99 markus 936: }
1.104 deraadt 937: snprintf(prompt, sizeof(prompt),
1.99 markus 938: "Retype %.30s@%.128s's new password: ",
1.175 dtucker 939: authctxt->server_user, host);
1.99 markus 940: retype = read_passphrase(prompt, 0);
941: if (strcmp(password, retype) != 0) {
1.204 djm 942: explicit_bzero(password, strlen(password));
1.197 djm 943: free(password);
1.116 itojun 944: logit("Mismatch; try again, EOF to quit.");
1.99 markus 945: password = NULL;
946: }
1.204 djm 947: explicit_bzero(retype, strlen(retype));
1.197 djm 948: free(retype);
1.99 markus 949: }
950: packet_put_cstring(password);
1.204 djm 951: explicit_bzero(password, strlen(password));
1.197 djm 952: free(password);
1.99 markus 953: packet_add_padding(64);
954: packet_send();
1.104 deraadt 955:
956: dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
1.99 markus 957: &input_userauth_passwd_changereq);
1.218 markus 958: return 0;
1.117 markus 959: }
960:
961: static int
1.214 djm 962: identity_sign(struct identity *id, u_char **sigp, size_t *lenp,
963: const u_char *data, size_t datalen, u_int compat)
1.117 markus 964: {
965: Key *prv;
966: int ret;
1.99 markus 967:
1.117 markus 968: /* the agent supports this key */
1.214 djm 969: if (id->agent_fd)
970: return ssh_agent_sign(id->agent_fd, id->key, sigp, lenp,
971: data, datalen, compat);
972:
1.117 markus 973: /*
974: * we have already loaded the private key or
975: * the private key is stored in external hardware
976: */
1.209 djm 977: if (id->isprivate || (id->key->flags & SSHKEY_FLAG_EXT))
1.214 djm 978: return (sshkey_sign(id->key, sigp, lenp, data, datalen,
979: compat));
1.117 markus 980: /* load the private key from the file */
1.191 dtucker 981: if ((prv = load_identity_file(id->filename, id->userprovided)) == NULL)
1.214 djm 982: return (-1); /* XXX return decent error code */
983: ret = sshkey_sign(prv, sigp, lenp, data, datalen, compat);
984: sshkey_free(prv);
1.117 markus 985: return (ret);
1.51 markus 986: }
987:
1.76 itojun 988: static int
1.117 markus 989: sign_and_send_pubkey(Authctxt *authctxt, Identity *id)
1.1 markus 990: {
991: Buffer b;
1.32 markus 992: u_char *blob, *signature;
1.214 djm 993: u_int bloblen;
994: size_t slen;
1.120 markus 995: u_int skip = 0;
1.17 markus 996: int ret = -1;
1.23 markus 997: int have_sig = 1;
1.182 djm 998: char *fp;
1.1 markus 999:
1.212 djm 1000: fp = key_fingerprint(id->key, options.fingerprint_hash, SSH_FP_DEFAULT);
1.182 djm 1001: debug3("sign_and_send_pubkey: %s %s", key_type(id->key), fp);
1.197 djm 1002: free(fp);
1.51 markus 1003:
1.117 markus 1004: if (key_to_blob(id->key, &blob, &bloblen) == 0) {
1.28 markus 1005: /* we cannot handle this key */
1.30 markus 1006: debug3("sign_and_send_pubkey: cannot handle key");
1.28 markus 1007: return 0;
1008: }
1.1 markus 1009: /* data to be signed */
1010: buffer_init(&b);
1.26 markus 1011: if (datafellows & SSH_OLD_SESSIONID) {
1012: buffer_append(&b, session_id2, session_id2_len);
1.41 stevesk 1013: skip = session_id2_len;
1.26 markus 1014: } else {
1.14 markus 1015: buffer_put_string(&b, session_id2, session_id2_len);
1016: skip = buffer_len(&b);
1017: }
1.1 markus 1018: buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
1.20 markus 1019: buffer_put_cstring(&b, authctxt->server_user);
1.10 markus 1020: buffer_put_cstring(&b,
1.30 markus 1021: datafellows & SSH_BUG_PKSERVICE ?
1.10 markus 1022: "ssh-userauth" :
1.20 markus 1023: authctxt->service);
1.30 markus 1024: if (datafellows & SSH_BUG_PKAUTH) {
1025: buffer_put_char(&b, have_sig);
1026: } else {
1027: buffer_put_cstring(&b, authctxt->method->name);
1028: buffer_put_char(&b, have_sig);
1.117 markus 1029: buffer_put_cstring(&b, key_ssh_name(id->key));
1.30 markus 1030: }
1.1 markus 1031: buffer_put_string(&b, blob, bloblen);
1032:
1033: /* generate signature */
1.117 markus 1034: ret = identity_sign(id, &signature, &slen,
1.214 djm 1035: buffer_ptr(&b), buffer_len(&b), datafellows);
1036: if (ret != 0) {
1.197 djm 1037: free(blob);
1.17 markus 1038: buffer_free(&b);
1039: return 0;
1040: }
1.28 markus 1041: #ifdef DEBUG_PK
1.1 markus 1042: buffer_dump(&b);
1043: #endif
1.30 markus 1044: if (datafellows & SSH_BUG_PKSERVICE) {
1.10 markus 1045: buffer_clear(&b);
1046: buffer_append(&b, session_id2, session_id2_len);
1.51 markus 1047: skip = session_id2_len;
1.10 markus 1048: buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
1.20 markus 1049: buffer_put_cstring(&b, authctxt->server_user);
1050: buffer_put_cstring(&b, authctxt->service);
1.23 markus 1051: buffer_put_cstring(&b, authctxt->method->name);
1052: buffer_put_char(&b, have_sig);
1.30 markus 1053: if (!(datafellows & SSH_BUG_PKAUTH))
1.117 markus 1054: buffer_put_cstring(&b, key_ssh_name(id->key));
1.10 markus 1055: buffer_put_string(&b, blob, bloblen);
1056: }
1.197 djm 1057: free(blob);
1.51 markus 1058:
1.1 markus 1059: /* append signature */
1060: buffer_put_string(&b, signature, slen);
1.197 djm 1061: free(signature);
1.1 markus 1062:
1063: /* skip session id and packet type */
1.14 markus 1064: if (buffer_len(&b) < skip + 1)
1.20 markus 1065: fatal("userauth_pubkey: internal error");
1.14 markus 1066: buffer_consume(&b, skip + 1);
1.1 markus 1067:
1068: /* put remaining data from buffer into packet */
1069: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1070: packet_put_raw(buffer_ptr(&b), buffer_len(&b));
1071: buffer_free(&b);
1072: packet_send();
1.17 markus 1073:
1074: return 1;
1.16 markus 1075: }
1076:
1.76 itojun 1077: static int
1.117 markus 1078: send_pubkey_test(Authctxt *authctxt, Identity *id)
1.20 markus 1079: {
1.51 markus 1080: u_char *blob;
1.97 markus 1081: u_int bloblen, have_sig = 0;
1.20 markus 1082:
1.51 markus 1083: debug3("send_pubkey_test");
1.16 markus 1084:
1.117 markus 1085: if (key_to_blob(id->key, &blob, &bloblen) == 0) {
1.51 markus 1086: /* we cannot handle this key */
1087: debug3("send_pubkey_test: cannot handle key");
1.16 markus 1088: return 0;
1089: }
1.51 markus 1090: /* register callback for USERAUTH_PK_OK message */
1091: dispatch_set(SSH2_MSG_USERAUTH_PK_OK, &input_userauth_pk_ok);
1092:
1093: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1094: packet_put_cstring(authctxt->server_user);
1095: packet_put_cstring(authctxt->service);
1096: packet_put_cstring(authctxt->method->name);
1097: packet_put_char(have_sig);
1098: if (!(datafellows & SSH_BUG_PKAUTH))
1.117 markus 1099: packet_put_cstring(key_ssh_name(id->key));
1.51 markus 1100: packet_put_string(blob, bloblen);
1.197 djm 1101: free(blob);
1.51 markus 1102: packet_send();
1103: return 1;
1104: }
1105:
1.76 itojun 1106: static Key *
1.191 dtucker 1107: load_identity_file(char *filename, int userprovided)
1.51 markus 1108: {
1109: Key *private;
1110: char prompt[300], *passphrase;
1.215 djm 1111: int r, perm_ok = 0, quit = 0, i;
1.52 markus 1112: struct stat st;
1.16 markus 1113:
1.52 markus 1114: if (stat(filename, &st) < 0) {
1.191 dtucker 1115: (userprovided ? logit : debug3)("no such identity: %s: %s",
1116: filename, strerror(errno));
1.52 markus 1117: return NULL;
1118: }
1.214 djm 1119: snprintf(prompt, sizeof prompt,
1120: "Enter passphrase for key '%.100s': ", filename);
1121: for (i = 0; i <= options.number_of_password_prompts; i++) {
1122: if (i == 0)
1123: passphrase = "";
1124: else {
1.20 markus 1125: passphrase = read_passphrase(prompt, 0);
1.214 djm 1126: if (*passphrase == '\0') {
1.20 markus 1127: debug2("no passphrase given, try next key");
1.214 djm 1128: free(passphrase);
1129: break;
1130: }
1131: }
1132: switch ((r = sshkey_load_private_type(KEY_UNSPEC, filename,
1133: passphrase, &private, NULL, &perm_ok))) {
1134: case 0:
1135: break;
1136: case SSH_ERR_KEY_WRONG_PASSPHRASE:
1137: if (options.batch_mode) {
1138: quit = 1;
1139: break;
1140: }
1.215 djm 1141: if (i != 0)
1142: debug2("bad passphrase given, try again...");
1.214 djm 1143: break;
1144: case SSH_ERR_SYSTEM_ERROR:
1145: if (errno == ENOENT) {
1146: debug2("Load key \"%s\": %s",
1147: filename, ssh_err(r));
1.51 markus 1148: quit = 1;
1.214 djm 1149: break;
1.20 markus 1150: }
1.214 djm 1151: /* FALLTHROUGH */
1152: default:
1153: error("Load key \"%s\": %s", filename, ssh_err(r));
1154: quit = 1;
1155: break;
1156: }
1157: if (i > 0) {
1.204 djm 1158: explicit_bzero(passphrase, strlen(passphrase));
1.197 djm 1159: free(passphrase);
1.16 markus 1160: }
1.214 djm 1161: if (private != NULL || quit)
1162: break;
1.16 markus 1163: }
1.51 markus 1164: return private;
1165: }
1166:
1.117 markus 1167: /*
1168: * try keys in the following order:
1169: * 1. agent keys that are found in the config file
1170: * 2. other agent keys
1171: * 3. keys that are only listed in the config file
1172: */
1173: static void
1174: pubkey_prepare(Authctxt *authctxt)
1.51 markus 1175: {
1.214 djm 1176: struct identity *id, *id2, *tmp;
1177: struct idlist agent, files, *preferred;
1178: struct sshkey *key;
1179: int agent_fd, i, r, found;
1180: size_t j;
1181: struct ssh_identitylist *idlist;
1.51 markus 1182:
1.117 markus 1183: TAILQ_INIT(&agent); /* keys from the agent */
1184: TAILQ_INIT(&files); /* keys from the config file */
1185: preferred = &authctxt->keys;
1186: TAILQ_INIT(preferred); /* preferred order of keys */
1187:
1.190 djm 1188: /* list of keys stored in the filesystem and PKCS#11 */
1.117 markus 1189: for (i = 0; i < options.num_identity_files; i++) {
1190: key = options.identity_keys[i];
1191: if (key && key->type == KEY_RSA1)
1.180 djm 1192: continue;
1193: if (key && key->cert && key->cert->type != SSH2_CERT_TYPE_USER)
1.117 markus 1194: continue;
1195: options.identity_keys[i] = NULL;
1.150 djm 1196: id = xcalloc(1, sizeof(*id));
1.117 markus 1197: id->key = key;
1198: id->filename = xstrdup(options.identity_files[i]);
1.192 dtucker 1199: id->userprovided = options.identity_file_userprovided[i];
1.117 markus 1200: TAILQ_INSERT_TAIL(&files, id, next);
1.190 djm 1201: }
1202: /* Prefer PKCS11 keys that are explicitly listed */
1203: TAILQ_FOREACH_SAFE(id, &files, next, tmp) {
1.209 djm 1204: if (id->key == NULL || (id->key->flags & SSHKEY_FLAG_EXT) == 0)
1.190 djm 1205: continue;
1206: found = 0;
1207: TAILQ_FOREACH(id2, &files, next) {
1208: if (id2->key == NULL ||
1.209 djm 1209: (id2->key->flags & SSHKEY_FLAG_EXT) == 0)
1.190 djm 1210: continue;
1.214 djm 1211: if (sshkey_equal(id->key, id2->key)) {
1.190 djm 1212: TAILQ_REMOVE(&files, id, next);
1213: TAILQ_INSERT_TAIL(preferred, id, next);
1214: found = 1;
1215: break;
1216: }
1217: }
1218: /* If IdentitiesOnly set and key not found then don't use it */
1219: if (!found && options.identities_only) {
1220: TAILQ_REMOVE(&files, id, next);
1.203 tedu 1221: explicit_bzero(id, sizeof(*id));
1.190 djm 1222: free(id);
1223: }
1.117 markus 1224: }
1225: /* list of keys supported by the agent */
1.214 djm 1226: if ((r = ssh_get_authentication_socket(&agent_fd)) != 0) {
1227: if (r != SSH_ERR_AGENT_NOT_PRESENT)
1228: debug("%s: ssh_get_authentication_socket: %s",
1229: __func__, ssh_err(r));
1230: } else if ((r = ssh_fetch_identitylist(agent_fd, 2, &idlist)) != 0) {
1231: if (r != SSH_ERR_AGENT_NO_IDENTITIES)
1232: debug("%s: ssh_fetch_identitylist: %s",
1233: __func__, ssh_err(r));
1234: } else {
1235: for (j = 0; j < idlist->nkeys; j++) {
1.117 markus 1236: found = 0;
1237: TAILQ_FOREACH(id, &files, next) {
1.214 djm 1238: /*
1239: * agent keys from the config file are
1240: * preferred
1241: */
1242: if (sshkey_equal(idlist->keys[j], id->key)) {
1.117 markus 1243: TAILQ_REMOVE(&files, id, next);
1244: TAILQ_INSERT_TAIL(preferred, id, next);
1.214 djm 1245: id->agent_fd = agent_fd;
1.117 markus 1246: found = 1;
1247: break;
1248: }
1249: }
1.135 markus 1250: if (!found && !options.identities_only) {
1.150 djm 1251: id = xcalloc(1, sizeof(*id));
1.214 djm 1252: /* XXX "steals" key/comment from idlist */
1253: id->key = idlist->keys[j];
1254: id->filename = idlist->comments[j];
1255: idlist->keys[j] = NULL;
1256: idlist->comments[j] = NULL;
1257: id->agent_fd = agent_fd;
1.117 markus 1258: TAILQ_INSERT_TAIL(&agent, id, next);
1259: }
1260: }
1.214 djm 1261: ssh_free_identitylist(idlist);
1.117 markus 1262: /* append remaining agent keys */
1263: for (id = TAILQ_FIRST(&agent); id; id = TAILQ_FIRST(&agent)) {
1264: TAILQ_REMOVE(&agent, id, next);
1265: TAILQ_INSERT_TAIL(preferred, id, next);
1266: }
1.214 djm 1267: authctxt->agent_fd = agent_fd;
1.117 markus 1268: }
1269: /* append remaining keys from the config file */
1270: for (id = TAILQ_FIRST(&files); id; id = TAILQ_FIRST(&files)) {
1271: TAILQ_REMOVE(&files, id, next);
1272: TAILQ_INSERT_TAIL(preferred, id, next);
1273: }
1274: TAILQ_FOREACH(id, preferred, next) {
1.191 dtucker 1275: debug2("key: %s (%p),%s", id->filename, id->key,
1276: id->userprovided ? " explicit" : "");
1.117 markus 1277: }
1.17 markus 1278: }
1279:
1.117 markus 1280: static void
1281: pubkey_cleanup(Authctxt *authctxt)
1.51 markus 1282: {
1.117 markus 1283: Identity *id;
1.51 markus 1284:
1.214 djm 1285: if (authctxt->agent_fd != -1)
1286: ssh_close_authentication_socket(authctxt->agent_fd);
1.117 markus 1287: for (id = TAILQ_FIRST(&authctxt->keys); id;
1288: id = TAILQ_FIRST(&authctxt->keys)) {
1289: TAILQ_REMOVE(&authctxt->keys, id, next);
1290: if (id->key)
1.214 djm 1291: sshkey_free(id->key);
1.197 djm 1292: free(id->filename);
1293: free(id);
1.117 markus 1294: }
1.1 markus 1295: }
1296:
1.20 markus 1297: int
1298: userauth_pubkey(Authctxt *authctxt)
1299: {
1.117 markus 1300: Identity *id;
1.20 markus 1301: int sent = 0;
1302:
1.117 markus 1303: while ((id = TAILQ_FIRST(&authctxt->keys))) {
1304: if (id->tried++)
1305: return (0);
1.127 markus 1306: /* move key to the end of the queue */
1.117 markus 1307: TAILQ_REMOVE(&authctxt->keys, id, next);
1308: TAILQ_INSERT_TAIL(&authctxt->keys, id, next);
1309: /*
1310: * send a test message if we have the public key. for
1311: * encrypted keys we cannot do this and have to load the
1312: * private key instead
1313: */
1.200 djm 1314: if (id->key != NULL) {
1315: if (key_type_plain(id->key->type) == KEY_RSA &&
1316: (datafellows & SSH_BUG_RSASIGMD5) != 0) {
1317: debug("Skipped %s key %s for RSA/MD5 server",
1318: key_type(id->key), id->filename);
1319: } else if (id->key->type != KEY_RSA1) {
1320: debug("Offering %s public key: %s",
1321: key_type(id->key), id->filename);
1322: sent = send_pubkey_test(authctxt, id);
1323: }
1324: } else {
1.117 markus 1325: debug("Trying private key: %s", id->filename);
1.191 dtucker 1326: id->key = load_identity_file(id->filename,
1327: id->userprovided);
1.117 markus 1328: if (id->key != NULL) {
1329: id->isprivate = 1;
1.200 djm 1330: if (key_type_plain(id->key->type) == KEY_RSA &&
1331: (datafellows & SSH_BUG_RSASIGMD5) != 0) {
1332: debug("Skipped %s key %s for RSA/MD5 "
1333: "server", key_type(id->key),
1334: id->filename);
1335: } else {
1336: sent = sign_and_send_pubkey(
1337: authctxt, id);
1338: }
1.117 markus 1339: key_free(id->key);
1340: id->key = NULL;
1.51 markus 1341: }
1342: }
1.117 markus 1343: if (sent)
1344: return (sent);
1.28 markus 1345: }
1.117 markus 1346: return (0);
1.20 markus 1347: }
1348:
1.23 markus 1349: /*
1350: * Send userauth request message specifying keyboard-interactive method.
1351: */
1352: int
1353: userauth_kbdint(Authctxt *authctxt)
1354: {
1355: static int attempt = 0;
1356:
1357: if (attempt++ >= options.number_of_password_prompts)
1358: return 0;
1.82 markus 1359: /* disable if no SSH2_MSG_USERAUTH_INFO_REQUEST has been seen */
1360: if (attempt > 1 && !authctxt->info_req_seen) {
1361: debug3("userauth_kbdint: disable: no info_req_seen");
1362: dispatch_set(SSH2_MSG_USERAUTH_INFO_REQUEST, NULL);
1363: return 0;
1364: }
1.23 markus 1365:
1366: debug2("userauth_kbdint");
1367: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1368: packet_put_cstring(authctxt->server_user);
1369: packet_put_cstring(authctxt->service);
1370: packet_put_cstring(authctxt->method->name);
1371: packet_put_cstring(""); /* lang */
1372: packet_put_cstring(options.kbd_interactive_devices ?
1373: options.kbd_interactive_devices : "");
1374: packet_send();
1375:
1376: dispatch_set(SSH2_MSG_USERAUTH_INFO_REQUEST, &input_userauth_info_req);
1377: return 1;
1378: }
1379:
1380: /*
1.46 markus 1381: * parse INFO_REQUEST, prompt user and send INFO_RESPONSE
1.23 markus 1382: */
1.218 markus 1383: int
1.92 markus 1384: input_userauth_info_req(int type, u_int32_t seq, void *ctxt)
1.23 markus 1385: {
1386: Authctxt *authctxt = ctxt;
1.46 markus 1387: char *name, *inst, *lang, *prompt, *response;
1.32 markus 1388: u_int num_prompts, i;
1.23 markus 1389: int echo = 0;
1390:
1391: debug2("input_userauth_info_req");
1392:
1393: if (authctxt == NULL)
1394: fatal("input_userauth_info_req: no authentication context");
1.82 markus 1395:
1396: authctxt->info_req_seen = 1;
1.23 markus 1397:
1398: name = packet_get_string(NULL);
1399: inst = packet_get_string(NULL);
1400: lang = packet_get_string(NULL);
1401: if (strlen(name) > 0)
1.116 itojun 1402: logit("%s", name);
1.23 markus 1403: if (strlen(inst) > 0)
1.116 itojun 1404: logit("%s", inst);
1.197 djm 1405: free(name);
1406: free(inst);
1407: free(lang);
1.23 markus 1408:
1409: num_prompts = packet_get_int();
1410: /*
1411: * Begin to build info response packet based on prompts requested.
1412: * We commit to providing the correct number of responses, so if
1413: * further on we run into a problem that prevents this, we have to
1414: * be sure and clean this up and send a correct error response.
1415: */
1416: packet_start(SSH2_MSG_USERAUTH_INFO_RESPONSE);
1417: packet_put_int(num_prompts);
1418:
1.73 markus 1419: debug2("input_userauth_info_req: num_prompts %d", num_prompts);
1.23 markus 1420: for (i = 0; i < num_prompts; i++) {
1421: prompt = packet_get_string(NULL);
1422: echo = packet_get_char();
1423:
1.77 markus 1424: response = read_passphrase(prompt, echo ? RP_ECHO : 0);
1.23 markus 1425:
1.49 markus 1426: packet_put_cstring(response);
1.204 djm 1427: explicit_bzero(response, strlen(response));
1.197 djm 1428: free(response);
1429: free(prompt);
1.23 markus 1430: }
1.90 markus 1431: packet_check_eom(); /* done with parsing incoming message. */
1.23 markus 1432:
1.85 markus 1433: packet_add_padding(64);
1.23 markus 1434: packet_send();
1.218 markus 1435: return 0;
1.68 markus 1436: }
1437:
1.100 markus 1438: static int
1.105 deraadt 1439: ssh_keysign(Key *key, u_char **sigp, u_int *lenp,
1.100 markus 1440: u_char *data, u_int datalen)
1441: {
1442: Buffer b;
1.101 markus 1443: struct stat st;
1.100 markus 1444: pid_t pid;
1.103 markus 1445: int to[2], from[2], status, version = 2;
1.100 markus 1446:
1.109 markus 1447: debug2("ssh_keysign called");
1.100 markus 1448:
1.101 markus 1449: if (stat(_PATH_SSH_KEY_SIGN, &st) < 0) {
1.179 dtucker 1450: error("ssh_keysign: not installed: %s", strerror(errno));
1.101 markus 1451: return -1;
1452: }
1.100 markus 1453: if (fflush(stdout) != 0)
1454: error("ssh_keysign: fflush: %s", strerror(errno));
1455: if (pipe(to) < 0) {
1456: error("ssh_keysign: pipe: %s", strerror(errno));
1457: return -1;
1458: }
1459: if (pipe(from) < 0) {
1460: error("ssh_keysign: pipe: %s", strerror(errno));
1461: return -1;
1462: }
1463: if ((pid = fork()) < 0) {
1464: error("ssh_keysign: fork: %s", strerror(errno));
1465: return -1;
1466: }
1467: if (pid == 0) {
1.174 dtucker 1468: /* keep the socket on exec */
1469: fcntl(packet_get_connection_in(), F_SETFD, 0);
1.155 markus 1470: permanently_drop_suid(getuid());
1.100 markus 1471: close(from[0]);
1472: if (dup2(from[1], STDOUT_FILENO) < 0)
1473: fatal("ssh_keysign: dup2: %s", strerror(errno));
1474: close(to[1]);
1475: if (dup2(to[0], STDIN_FILENO) < 0)
1476: fatal("ssh_keysign: dup2: %s", strerror(errno));
1.103 markus 1477: close(from[1]);
1478: close(to[0]);
1.102 markus 1479: execl(_PATH_SSH_KEY_SIGN, _PATH_SSH_KEY_SIGN, (char *) 0);
1.100 markus 1480: fatal("ssh_keysign: exec(%s): %s", _PATH_SSH_KEY_SIGN,
1481: strerror(errno));
1482: }
1483: close(from[1]);
1484: close(to[0]);
1485:
1486: buffer_init(&b);
1.103 markus 1487: buffer_put_int(&b, packet_get_connection_in()); /* send # of socket */
1.100 markus 1488: buffer_put_string(&b, data, datalen);
1.131 djm 1489: if (ssh_msg_send(to[1], version, &b) == -1)
1490: fatal("ssh_keysign: couldn't send request");
1.100 markus 1491:
1.110 djm 1492: if (ssh_msg_recv(from[0], &b) < 0) {
1.101 markus 1493: error("ssh_keysign: no reply");
1.134 markus 1494: buffer_free(&b);
1.100 markus 1495: return -1;
1496: }
1.101 markus 1497: close(from[0]);
1498: close(to[1]);
1499:
1.103 markus 1500: while (waitpid(pid, &status, 0) < 0)
1501: if (errno != EINTR)
1502: break;
1.101 markus 1503:
1.100 markus 1504: if (buffer_get_char(&b) != version) {
1.101 markus 1505: error("ssh_keysign: bad version");
1.134 markus 1506: buffer_free(&b);
1.100 markus 1507: return -1;
1508: }
1509: *sigp = buffer_get_string(&b, lenp);
1.134 markus 1510: buffer_free(&b);
1.100 markus 1511:
1512: return 0;
1513: }
1514:
1.68 markus 1515: int
1516: userauth_hostbased(Authctxt *authctxt)
1517: {
1518: Key *private = NULL;
1.100 markus 1519: Sensitive *sensitive = authctxt->sensitive;
1.68 markus 1520: Buffer b;
1521: u_char *signature, *blob;
1.179 dtucker 1522: char *chost, *pkalg, *p;
1.72 markus 1523: const char *service;
1.68 markus 1524: u_int blen, slen;
1.176 dtucker 1525: int ok, i, found = 0;
1.213 djm 1526:
1527: /* XXX provide some way to allow user to specify key types attempted */
1.68 markus 1528:
1529: /* check for a useful key */
1.100 markus 1530: for (i = 0; i < sensitive->nkeys; i++) {
1531: private = sensitive->keys[i];
1.68 markus 1532: if (private && private->type != KEY_RSA1) {
1533: found = 1;
1534: /* we take and free the key */
1.100 markus 1535: sensitive->keys[i] = NULL;
1.68 markus 1536: break;
1537: }
1538: }
1539: if (!found) {
1.109 markus 1540: debug("No more client hostkeys for hostbased authentication.");
1.68 markus 1541: return 0;
1542: }
1.211 djm 1543:
1544: debug("%s: trying hostkey type %s", __func__, key_type(private));
1545:
1.68 markus 1546: if (key_to_blob(private, &blob, &blen) == 0) {
1547: key_free(private);
1548: return 0;
1549: }
1.211 djm 1550:
1.84 markus 1551: /* figure out a name for the client host */
1.179 dtucker 1552: p = get_local_name(packet_get_connection_in());
1.84 markus 1553: if (p == NULL) {
1554: error("userauth_hostbased: cannot get local ipaddr/name");
1555: key_free(private);
1.197 djm 1556: free(blob);
1.84 markus 1557: return 0;
1558: }
1.150 djm 1559: xasprintf(&chost, "%s.", p);
1.84 markus 1560: debug2("userauth_hostbased: chost %s", chost);
1.197 djm 1561: free(p);
1.84 markus 1562:
1.72 markus 1563: service = datafellows & SSH_BUG_HBSERVICE ? "ssh-userauth" :
1564: authctxt->service;
1.68 markus 1565: pkalg = xstrdup(key_ssh_name(private));
1566: buffer_init(&b);
1567: /* construct data */
1.72 markus 1568: buffer_put_string(&b, session_id2, session_id2_len);
1.68 markus 1569: buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
1570: buffer_put_cstring(&b, authctxt->server_user);
1.72 markus 1571: buffer_put_cstring(&b, service);
1.68 markus 1572: buffer_put_cstring(&b, authctxt->method->name);
1573: buffer_put_cstring(&b, pkalg);
1574: buffer_put_string(&b, blob, blen);
1575: buffer_put_cstring(&b, chost);
1576: buffer_put_cstring(&b, authctxt->local_user);
1577: #ifdef DEBUG_PK
1578: buffer_dump(&b);
1579: #endif
1.100 markus 1580: if (sensitive->external_keysign)
1581: ok = ssh_keysign(private, &signature, &slen,
1582: buffer_ptr(&b), buffer_len(&b));
1583: else
1584: ok = key_sign(private, &signature, &slen,
1585: buffer_ptr(&b), buffer_len(&b));
1.68 markus 1586: key_free(private);
1587: buffer_free(&b);
1588: if (ok != 0) {
1589: error("key_sign failed");
1.197 djm 1590: free(chost);
1591: free(pkalg);
1592: free(blob);
1.68 markus 1593: return 0;
1594: }
1595: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1596: packet_put_cstring(authctxt->server_user);
1597: packet_put_cstring(authctxt->service);
1598: packet_put_cstring(authctxt->method->name);
1599: packet_put_cstring(pkalg);
1600: packet_put_string(blob, blen);
1601: packet_put_cstring(chost);
1602: packet_put_cstring(authctxt->local_user);
1603: packet_put_string(signature, slen);
1.204 djm 1604: explicit_bzero(signature, slen);
1.197 djm 1605: free(signature);
1606: free(chost);
1607: free(pkalg);
1608: free(blob);
1.68 markus 1609:
1610: packet_send();
1611: return 1;
1.23 markus 1612: }
1.170 djm 1613:
1.20 markus 1614: /* find auth method */
1615:
1616: /*
1617: * given auth method name, if configurable options permit this method fill
1618: * in auth_ident field and return true, otherwise return false.
1619: */
1.76 itojun 1620: static int
1.20 markus 1621: authmethod_is_enabled(Authmethod *method)
1622: {
1623: if (method == NULL)
1624: return 0;
1625: /* return false if options indicate this method is disabled */
1626: if (method->enabled == NULL || *method->enabled == 0)
1627: return 0;
1628: /* return false if batch mode is enabled but method needs interactive mode */
1629: if (method->batch_flag != NULL && *method->batch_flag != 0)
1630: return 0;
1631: return 1;
1632: }
1633:
1.76 itojun 1634: static Authmethod *
1.20 markus 1635: authmethod_lookup(const char *name)
1.1 markus 1636: {
1.20 markus 1637: Authmethod *method = NULL;
1638: if (name != NULL)
1639: for (method = authmethods; method->name != NULL; method++)
1640: if (strcmp(name, method->name) == 0)
1641: return method;
1642: debug2("Unrecognized authentication method name: %s", name ? name : "NULL");
1643: return NULL;
1644: }
1.1 markus 1645:
1.53 markus 1646: /* XXX internal state */
1647: static Authmethod *current = NULL;
1648: static char *supported = NULL;
1649: static char *preferred = NULL;
1.105 deraadt 1650:
1.20 markus 1651: /*
1652: * Given the authentication method list sent by the server, return the
1653: * next method we should try. If the server initially sends a nil list,
1.67 markus 1654: * use a built-in default list.
1.41 stevesk 1655: */
1.76 itojun 1656: static Authmethod *
1.20 markus 1657: authmethod_get(char *authlist)
1658: {
1.53 markus 1659: char *name = NULL;
1.97 markus 1660: u_int next;
1.41 stevesk 1661:
1.20 markus 1662: /* Use a suitable default if we're passed a nil list. */
1663: if (authlist == NULL || strlen(authlist) == 0)
1.53 markus 1664: authlist = options.preferred_authentications;
1.20 markus 1665:
1.53 markus 1666: if (supported == NULL || strcmp(authlist, supported) != 0) {
1667: debug3("start over, passed a different list %s", authlist);
1.197 djm 1668: free(supported);
1.53 markus 1669: supported = xstrdup(authlist);
1670: preferred = options.preferred_authentications;
1671: debug3("preferred %s", preferred);
1672: current = NULL;
1673: } else if (current != NULL && authmethod_is_enabled(current))
1674: return current;
1.20 markus 1675:
1.53 markus 1676: for (;;) {
1677: if ((name = match_list(preferred, supported, &next)) == NULL) {
1.109 markus 1678: debug("No more authentication methods to try.");
1.53 markus 1679: current = NULL;
1680: return NULL;
1681: }
1682: preferred += next;
1.23 markus 1683: debug3("authmethod_lookup %s", name);
1.53 markus 1684: debug3("remaining preferred: %s", preferred);
1685: if ((current = authmethod_lookup(name)) != NULL &&
1686: authmethod_is_enabled(current)) {
1.23 markus 1687: debug3("authmethod_is_enabled %s", name);
1.109 markus 1688: debug("Next authentication method: %s", name);
1.197 djm 1689: free(name);
1.53 markus 1690: return current;
1.23 markus 1691: }
1.198 dtucker 1692: free(name);
1.1 markus 1693: }
1.53 markus 1694: }
1.1 markus 1695:
1.79 stevesk 1696: static char *
1.53 markus 1697: authmethods_get(void)
1698: {
1699: Authmethod *method = NULL;
1.93 markus 1700: Buffer b;
1701: char *list;
1.27 provos 1702:
1.93 markus 1703: buffer_init(&b);
1.53 markus 1704: for (method = authmethods; method->name != NULL; method++) {
1705: if (authmethod_is_enabled(method)) {
1.93 markus 1706: if (buffer_len(&b) > 0)
1707: buffer_append(&b, ",", 1);
1708: buffer_append(&b, method->name, strlen(method->name));
1.53 markus 1709: }
1710: }
1.93 markus 1711: buffer_append(&b, "\0", 1);
1712: list = xstrdup(buffer_ptr(&b));
1713: buffer_free(&b);
1714: return list;
1.1 markus 1715: }
1.170 djm 1716:
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