Annotation of src/usr.bin/ssh/sshconnect2.c, Revision 1.220
1.220 ! djm 1: /* $OpenBSD: sshconnect2.c,v 1.219 2015/01/19 20:16:15 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 */
1.220 ! djm 726: int
1.121 markus 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);
1.220 ! djm 747: return 0;
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);
1.220 ! djm 761: return 0;
1.121 markus 762: }
1.220 ! djm 763: return 0;
1.121 markus 764: }
765:
1.169 djm 766: /* ARGSUSED */
1.220 ! djm 767: int
1.121 markus 768: input_gssapi_token(int type, u_int32_t plen, void *ctxt)
769: {
770: Authctxt *authctxt = ctxt;
771: gss_buffer_desc recv_tok;
1.130 markus 772: OM_uint32 status;
1.121 markus 773: u_int slen;
774:
775: if (authctxt == NULL)
776: fatal("input_gssapi_response: no authentication context");
777:
778: recv_tok.value = packet_get_string(&slen);
779: recv_tok.length = slen; /* safe typecast */
780:
781: packet_check_eom();
782:
1.130 markus 783: status = process_gssapi_token(ctxt, &recv_tok);
1.121 markus 784:
1.197 djm 785: free(recv_tok.value);
1.121 markus 786:
787: if (GSS_ERROR(status)) {
788: /* Start again with the next method in the list */
789: userauth(authctxt, NULL);
1.220 ! djm 790: return 0;
1.121 markus 791: }
1.220 ! djm 792: return 0;
1.121 markus 793: }
794:
1.169 djm 795: /* ARGSUSED */
1.220 ! djm 796: int
1.121 markus 797: input_gssapi_errtok(int type, u_int32_t plen, void *ctxt)
798: {
799: Authctxt *authctxt = ctxt;
800: Gssctxt *gssctxt;
801: gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
802: gss_buffer_desc recv_tok;
1.194 djm 803: OM_uint32 ms;
1.123 deraadt 804: u_int len;
1.121 markus 805:
806: if (authctxt == NULL)
807: fatal("input_gssapi_response: no authentication context");
808: gssctxt = authctxt->methoddata;
809:
1.123 deraadt 810: recv_tok.value = packet_get_string(&len);
811: recv_tok.length = len;
1.121 markus 812:
813: packet_check_eom();
814:
815: /* Stick it into GSSAPI and see what it says */
1.194 djm 816: (void)ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
1.140 djm 817: &recv_tok, &send_tok, NULL);
1.121 markus 818:
1.197 djm 819: free(recv_tok.value);
1.121 markus 820: gss_release_buffer(&ms, &send_tok);
821:
822: /* Server will be returning a failed packet after this one */
1.220 ! djm 823: return 0;
1.121 markus 824: }
825:
1.169 djm 826: /* ARGSUSED */
1.220 ! djm 827: int
1.121 markus 828: input_gssapi_error(int type, u_int32_t plen, void *ctxt)
829: {
830: char *msg;
831: char *lang;
832:
1.194 djm 833: /* maj */(void)packet_get_int();
834: /* min */(void)packet_get_int();
1.121 markus 835: msg=packet_get_string(NULL);
836: lang=packet_get_string(NULL);
837:
838: packet_check_eom();
839:
1.143 stevesk 840: debug("Server GSSAPI Error:\n%s", msg);
1.197 djm 841: free(msg);
842: free(lang);
1.220 ! djm 843: return 0;
1.121 markus 844: }
845: #endif /* GSSAPI */
1.20 markus 846:
1.1 markus 847: int
1.23 markus 848: userauth_none(Authctxt *authctxt)
849: {
850: /* initial userauth request */
851: packet_start(SSH2_MSG_USERAUTH_REQUEST);
852: packet_put_cstring(authctxt->server_user);
853: packet_put_cstring(authctxt->service);
854: packet_put_cstring(authctxt->method->name);
855: packet_send();
856: return 1;
857: }
858:
859: int
1.20 markus 860: userauth_passwd(Authctxt *authctxt)
1.1 markus 861: {
1.6 markus 862: static int attempt = 0;
1.99 markus 863: char prompt[150];
1.1 markus 864: char *password;
1.175 dtucker 865: const char *host = options.host_key_alias ? options.host_key_alias :
866: authctxt->host;
1.6 markus 867:
1.13 todd 868: if (attempt++ >= options.number_of_password_prompts)
1.6 markus 869: return 0;
1.13 todd 870:
1.87 deraadt 871: if (attempt != 1)
1.13 todd 872: error("Permission denied, please try again.");
1.1 markus 873:
1.43 itojun 874: snprintf(prompt, sizeof(prompt), "%.30s@%.128s's password: ",
1.175 dtucker 875: authctxt->server_user, host);
1.1 markus 876: password = read_passphrase(prompt, 0);
877: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1.20 markus 878: packet_put_cstring(authctxt->server_user);
879: packet_put_cstring(authctxt->service);
1.23 markus 880: packet_put_cstring(authctxt->method->name);
1.1 markus 881: packet_put_char(0);
1.49 markus 882: packet_put_cstring(password);
1.204 djm 883: explicit_bzero(password, strlen(password));
1.197 djm 884: free(password);
1.85 markus 885: packet_add_padding(64);
1.1 markus 886: packet_send();
1.99 markus 887:
1.104 deraadt 888: dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
1.99 markus 889: &input_userauth_passwd_changereq);
890:
1.1 markus 891: return 1;
892: }
1.169 djm 893:
1.99 markus 894: /*
895: * parse PASSWD_CHANGEREQ, prompt user and send SSH2_MSG_USERAUTH_REQUEST
896: */
1.169 djm 897: /* ARGSUSED */
1.218 markus 898: int
1.153 djm 899: input_userauth_passwd_changereq(int type, u_int32_t seqnr, void *ctxt)
1.99 markus 900: {
901: Authctxt *authctxt = ctxt;
902: char *info, *lang, *password = NULL, *retype = NULL;
903: char prompt[150];
1.175 dtucker 904: const char *host = options.host_key_alias ? options.host_key_alias :
905: authctxt->host;
1.99 markus 906:
907: debug2("input_userauth_passwd_changereq");
908:
909: if (authctxt == NULL)
910: fatal("input_userauth_passwd_changereq: "
911: "no authentication context");
912:
913: info = packet_get_string(NULL);
914: lang = packet_get_string(NULL);
915: if (strlen(info) > 0)
1.116 itojun 916: logit("%s", info);
1.197 djm 917: free(info);
918: free(lang);
1.99 markus 919: packet_start(SSH2_MSG_USERAUTH_REQUEST);
920: packet_put_cstring(authctxt->server_user);
921: packet_put_cstring(authctxt->service);
922: packet_put_cstring(authctxt->method->name);
923: packet_put_char(1); /* additional info */
1.104 deraadt 924: snprintf(prompt, sizeof(prompt),
1.99 markus 925: "Enter %.30s@%.128s's old password: ",
1.175 dtucker 926: authctxt->server_user, host);
1.99 markus 927: password = read_passphrase(prompt, 0);
928: packet_put_cstring(password);
1.204 djm 929: explicit_bzero(password, strlen(password));
1.197 djm 930: free(password);
1.99 markus 931: password = NULL;
932: while (password == NULL) {
1.104 deraadt 933: snprintf(prompt, sizeof(prompt),
1.99 markus 934: "Enter %.30s@%.128s's new password: ",
1.175 dtucker 935: authctxt->server_user, host);
1.99 markus 936: password = read_passphrase(prompt, RP_ALLOW_EOF);
937: if (password == NULL) {
938: /* bail out */
1.218 markus 939: return 0;
1.99 markus 940: }
1.104 deraadt 941: snprintf(prompt, sizeof(prompt),
1.99 markus 942: "Retype %.30s@%.128s's new password: ",
1.175 dtucker 943: authctxt->server_user, host);
1.99 markus 944: retype = read_passphrase(prompt, 0);
945: if (strcmp(password, retype) != 0) {
1.204 djm 946: explicit_bzero(password, strlen(password));
1.197 djm 947: free(password);
1.116 itojun 948: logit("Mismatch; try again, EOF to quit.");
1.99 markus 949: password = NULL;
950: }
1.204 djm 951: explicit_bzero(retype, strlen(retype));
1.197 djm 952: free(retype);
1.99 markus 953: }
954: packet_put_cstring(password);
1.204 djm 955: explicit_bzero(password, strlen(password));
1.197 djm 956: free(password);
1.99 markus 957: packet_add_padding(64);
958: packet_send();
1.104 deraadt 959:
960: dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
1.99 markus 961: &input_userauth_passwd_changereq);
1.218 markus 962: return 0;
1.117 markus 963: }
964:
965: static int
1.214 djm 966: identity_sign(struct identity *id, u_char **sigp, size_t *lenp,
967: const u_char *data, size_t datalen, u_int compat)
1.117 markus 968: {
969: Key *prv;
970: int ret;
1.99 markus 971:
1.117 markus 972: /* the agent supports this key */
1.214 djm 973: if (id->agent_fd)
974: return ssh_agent_sign(id->agent_fd, id->key, sigp, lenp,
975: data, datalen, compat);
976:
1.117 markus 977: /*
978: * we have already loaded the private key or
979: * the private key is stored in external hardware
980: */
1.209 djm 981: if (id->isprivate || (id->key->flags & SSHKEY_FLAG_EXT))
1.214 djm 982: return (sshkey_sign(id->key, sigp, lenp, data, datalen,
983: compat));
1.117 markus 984: /* load the private key from the file */
1.191 dtucker 985: if ((prv = load_identity_file(id->filename, id->userprovided)) == NULL)
1.214 djm 986: return (-1); /* XXX return decent error code */
987: ret = sshkey_sign(prv, sigp, lenp, data, datalen, compat);
988: sshkey_free(prv);
1.117 markus 989: return (ret);
1.51 markus 990: }
991:
1.76 itojun 992: static int
1.117 markus 993: sign_and_send_pubkey(Authctxt *authctxt, Identity *id)
1.1 markus 994: {
995: Buffer b;
1.32 markus 996: u_char *blob, *signature;
1.214 djm 997: u_int bloblen;
998: size_t slen;
1.120 markus 999: u_int skip = 0;
1.17 markus 1000: int ret = -1;
1.23 markus 1001: int have_sig = 1;
1.182 djm 1002: char *fp;
1.1 markus 1003:
1.212 djm 1004: fp = key_fingerprint(id->key, options.fingerprint_hash, SSH_FP_DEFAULT);
1.182 djm 1005: debug3("sign_and_send_pubkey: %s %s", key_type(id->key), fp);
1.197 djm 1006: free(fp);
1.51 markus 1007:
1.117 markus 1008: if (key_to_blob(id->key, &blob, &bloblen) == 0) {
1.28 markus 1009: /* we cannot handle this key */
1.30 markus 1010: debug3("sign_and_send_pubkey: cannot handle key");
1.28 markus 1011: return 0;
1012: }
1.1 markus 1013: /* data to be signed */
1014: buffer_init(&b);
1.26 markus 1015: if (datafellows & SSH_OLD_SESSIONID) {
1016: buffer_append(&b, session_id2, session_id2_len);
1.41 stevesk 1017: skip = session_id2_len;
1.26 markus 1018: } else {
1.14 markus 1019: buffer_put_string(&b, session_id2, session_id2_len);
1020: skip = buffer_len(&b);
1021: }
1.1 markus 1022: buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
1.20 markus 1023: buffer_put_cstring(&b, authctxt->server_user);
1.10 markus 1024: buffer_put_cstring(&b,
1.30 markus 1025: datafellows & SSH_BUG_PKSERVICE ?
1.10 markus 1026: "ssh-userauth" :
1.20 markus 1027: authctxt->service);
1.30 markus 1028: if (datafellows & SSH_BUG_PKAUTH) {
1029: buffer_put_char(&b, have_sig);
1030: } else {
1031: buffer_put_cstring(&b, authctxt->method->name);
1032: buffer_put_char(&b, have_sig);
1.117 markus 1033: buffer_put_cstring(&b, key_ssh_name(id->key));
1.30 markus 1034: }
1.1 markus 1035: buffer_put_string(&b, blob, bloblen);
1036:
1037: /* generate signature */
1.117 markus 1038: ret = identity_sign(id, &signature, &slen,
1.214 djm 1039: buffer_ptr(&b), buffer_len(&b), datafellows);
1040: if (ret != 0) {
1.197 djm 1041: free(blob);
1.17 markus 1042: buffer_free(&b);
1043: return 0;
1044: }
1.28 markus 1045: #ifdef DEBUG_PK
1.1 markus 1046: buffer_dump(&b);
1047: #endif
1.30 markus 1048: if (datafellows & SSH_BUG_PKSERVICE) {
1.10 markus 1049: buffer_clear(&b);
1050: buffer_append(&b, session_id2, session_id2_len);
1.51 markus 1051: skip = session_id2_len;
1.10 markus 1052: buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
1.20 markus 1053: buffer_put_cstring(&b, authctxt->server_user);
1054: buffer_put_cstring(&b, authctxt->service);
1.23 markus 1055: buffer_put_cstring(&b, authctxt->method->name);
1056: buffer_put_char(&b, have_sig);
1.30 markus 1057: if (!(datafellows & SSH_BUG_PKAUTH))
1.117 markus 1058: buffer_put_cstring(&b, key_ssh_name(id->key));
1.10 markus 1059: buffer_put_string(&b, blob, bloblen);
1060: }
1.197 djm 1061: free(blob);
1.51 markus 1062:
1.1 markus 1063: /* append signature */
1064: buffer_put_string(&b, signature, slen);
1.197 djm 1065: free(signature);
1.1 markus 1066:
1067: /* skip session id and packet type */
1.14 markus 1068: if (buffer_len(&b) < skip + 1)
1.20 markus 1069: fatal("userauth_pubkey: internal error");
1.14 markus 1070: buffer_consume(&b, skip + 1);
1.1 markus 1071:
1072: /* put remaining data from buffer into packet */
1073: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1074: packet_put_raw(buffer_ptr(&b), buffer_len(&b));
1075: buffer_free(&b);
1076: packet_send();
1.17 markus 1077:
1078: return 1;
1.16 markus 1079: }
1080:
1.76 itojun 1081: static int
1.117 markus 1082: send_pubkey_test(Authctxt *authctxt, Identity *id)
1.20 markus 1083: {
1.51 markus 1084: u_char *blob;
1.97 markus 1085: u_int bloblen, have_sig = 0;
1.20 markus 1086:
1.51 markus 1087: debug3("send_pubkey_test");
1.16 markus 1088:
1.117 markus 1089: if (key_to_blob(id->key, &blob, &bloblen) == 0) {
1.51 markus 1090: /* we cannot handle this key */
1091: debug3("send_pubkey_test: cannot handle key");
1.16 markus 1092: return 0;
1093: }
1.51 markus 1094: /* register callback for USERAUTH_PK_OK message */
1095: dispatch_set(SSH2_MSG_USERAUTH_PK_OK, &input_userauth_pk_ok);
1096:
1097: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1098: packet_put_cstring(authctxt->server_user);
1099: packet_put_cstring(authctxt->service);
1100: packet_put_cstring(authctxt->method->name);
1101: packet_put_char(have_sig);
1102: if (!(datafellows & SSH_BUG_PKAUTH))
1.117 markus 1103: packet_put_cstring(key_ssh_name(id->key));
1.51 markus 1104: packet_put_string(blob, bloblen);
1.197 djm 1105: free(blob);
1.51 markus 1106: packet_send();
1107: return 1;
1108: }
1109:
1.76 itojun 1110: static Key *
1.191 dtucker 1111: load_identity_file(char *filename, int userprovided)
1.51 markus 1112: {
1113: Key *private;
1114: char prompt[300], *passphrase;
1.215 djm 1115: int r, perm_ok = 0, quit = 0, i;
1.52 markus 1116: struct stat st;
1.16 markus 1117:
1.52 markus 1118: if (stat(filename, &st) < 0) {
1.191 dtucker 1119: (userprovided ? logit : debug3)("no such identity: %s: %s",
1120: filename, strerror(errno));
1.52 markus 1121: return NULL;
1122: }
1.214 djm 1123: snprintf(prompt, sizeof prompt,
1124: "Enter passphrase for key '%.100s': ", filename);
1125: for (i = 0; i <= options.number_of_password_prompts; i++) {
1126: if (i == 0)
1127: passphrase = "";
1128: else {
1.20 markus 1129: passphrase = read_passphrase(prompt, 0);
1.214 djm 1130: if (*passphrase == '\0') {
1.20 markus 1131: debug2("no passphrase given, try next key");
1.214 djm 1132: free(passphrase);
1133: break;
1134: }
1135: }
1136: switch ((r = sshkey_load_private_type(KEY_UNSPEC, filename,
1137: passphrase, &private, NULL, &perm_ok))) {
1138: case 0:
1139: break;
1140: case SSH_ERR_KEY_WRONG_PASSPHRASE:
1141: if (options.batch_mode) {
1142: quit = 1;
1143: break;
1144: }
1.215 djm 1145: if (i != 0)
1146: debug2("bad passphrase given, try again...");
1.214 djm 1147: break;
1148: case SSH_ERR_SYSTEM_ERROR:
1149: if (errno == ENOENT) {
1150: debug2("Load key \"%s\": %s",
1151: filename, ssh_err(r));
1.51 markus 1152: quit = 1;
1.214 djm 1153: break;
1.20 markus 1154: }
1.214 djm 1155: /* FALLTHROUGH */
1156: default:
1157: error("Load key \"%s\": %s", filename, ssh_err(r));
1158: quit = 1;
1159: break;
1160: }
1161: if (i > 0) {
1.204 djm 1162: explicit_bzero(passphrase, strlen(passphrase));
1.197 djm 1163: free(passphrase);
1.16 markus 1164: }
1.214 djm 1165: if (private != NULL || quit)
1166: break;
1.16 markus 1167: }
1.51 markus 1168: return private;
1169: }
1170:
1.117 markus 1171: /*
1172: * try keys in the following order:
1173: * 1. agent keys that are found in the config file
1174: * 2. other agent keys
1175: * 3. keys that are only listed in the config file
1176: */
1177: static void
1178: pubkey_prepare(Authctxt *authctxt)
1.51 markus 1179: {
1.214 djm 1180: struct identity *id, *id2, *tmp;
1181: struct idlist agent, files, *preferred;
1182: struct sshkey *key;
1183: int agent_fd, i, r, found;
1184: size_t j;
1185: struct ssh_identitylist *idlist;
1.51 markus 1186:
1.117 markus 1187: TAILQ_INIT(&agent); /* keys from the agent */
1188: TAILQ_INIT(&files); /* keys from the config file */
1189: preferred = &authctxt->keys;
1190: TAILQ_INIT(preferred); /* preferred order of keys */
1191:
1.190 djm 1192: /* list of keys stored in the filesystem and PKCS#11 */
1.117 markus 1193: for (i = 0; i < options.num_identity_files; i++) {
1194: key = options.identity_keys[i];
1195: if (key && key->type == KEY_RSA1)
1.180 djm 1196: continue;
1197: if (key && key->cert && key->cert->type != SSH2_CERT_TYPE_USER)
1.117 markus 1198: continue;
1199: options.identity_keys[i] = NULL;
1.150 djm 1200: id = xcalloc(1, sizeof(*id));
1.117 markus 1201: id->key = key;
1202: id->filename = xstrdup(options.identity_files[i]);
1.192 dtucker 1203: id->userprovided = options.identity_file_userprovided[i];
1.117 markus 1204: TAILQ_INSERT_TAIL(&files, id, next);
1.190 djm 1205: }
1206: /* Prefer PKCS11 keys that are explicitly listed */
1207: TAILQ_FOREACH_SAFE(id, &files, next, tmp) {
1.209 djm 1208: if (id->key == NULL || (id->key->flags & SSHKEY_FLAG_EXT) == 0)
1.190 djm 1209: continue;
1210: found = 0;
1211: TAILQ_FOREACH(id2, &files, next) {
1212: if (id2->key == NULL ||
1.209 djm 1213: (id2->key->flags & SSHKEY_FLAG_EXT) == 0)
1.190 djm 1214: continue;
1.214 djm 1215: if (sshkey_equal(id->key, id2->key)) {
1.190 djm 1216: TAILQ_REMOVE(&files, id, next);
1217: TAILQ_INSERT_TAIL(preferred, id, next);
1218: found = 1;
1219: break;
1220: }
1221: }
1222: /* If IdentitiesOnly set and key not found then don't use it */
1223: if (!found && options.identities_only) {
1224: TAILQ_REMOVE(&files, id, next);
1.203 tedu 1225: explicit_bzero(id, sizeof(*id));
1.190 djm 1226: free(id);
1227: }
1.117 markus 1228: }
1229: /* list of keys supported by the agent */
1.214 djm 1230: if ((r = ssh_get_authentication_socket(&agent_fd)) != 0) {
1231: if (r != SSH_ERR_AGENT_NOT_PRESENT)
1232: debug("%s: ssh_get_authentication_socket: %s",
1233: __func__, ssh_err(r));
1234: } else if ((r = ssh_fetch_identitylist(agent_fd, 2, &idlist)) != 0) {
1235: if (r != SSH_ERR_AGENT_NO_IDENTITIES)
1236: debug("%s: ssh_fetch_identitylist: %s",
1237: __func__, ssh_err(r));
1238: } else {
1239: for (j = 0; j < idlist->nkeys; j++) {
1.117 markus 1240: found = 0;
1241: TAILQ_FOREACH(id, &files, next) {
1.214 djm 1242: /*
1243: * agent keys from the config file are
1244: * preferred
1245: */
1246: if (sshkey_equal(idlist->keys[j], id->key)) {
1.117 markus 1247: TAILQ_REMOVE(&files, id, next);
1248: TAILQ_INSERT_TAIL(preferred, id, next);
1.214 djm 1249: id->agent_fd = agent_fd;
1.117 markus 1250: found = 1;
1251: break;
1252: }
1253: }
1.135 markus 1254: if (!found && !options.identities_only) {
1.150 djm 1255: id = xcalloc(1, sizeof(*id));
1.214 djm 1256: /* XXX "steals" key/comment from idlist */
1257: id->key = idlist->keys[j];
1258: id->filename = idlist->comments[j];
1259: idlist->keys[j] = NULL;
1260: idlist->comments[j] = NULL;
1261: id->agent_fd = agent_fd;
1.117 markus 1262: TAILQ_INSERT_TAIL(&agent, id, next);
1263: }
1264: }
1.214 djm 1265: ssh_free_identitylist(idlist);
1.117 markus 1266: /* append remaining agent keys */
1267: for (id = TAILQ_FIRST(&agent); id; id = TAILQ_FIRST(&agent)) {
1268: TAILQ_REMOVE(&agent, id, next);
1269: TAILQ_INSERT_TAIL(preferred, id, next);
1270: }
1.214 djm 1271: authctxt->agent_fd = agent_fd;
1.117 markus 1272: }
1273: /* append remaining keys from the config file */
1274: for (id = TAILQ_FIRST(&files); id; id = TAILQ_FIRST(&files)) {
1275: TAILQ_REMOVE(&files, id, next);
1276: TAILQ_INSERT_TAIL(preferred, id, next);
1277: }
1278: TAILQ_FOREACH(id, preferred, next) {
1.191 dtucker 1279: debug2("key: %s (%p),%s", id->filename, id->key,
1280: id->userprovided ? " explicit" : "");
1.117 markus 1281: }
1.17 markus 1282: }
1283:
1.117 markus 1284: static void
1285: pubkey_cleanup(Authctxt *authctxt)
1.51 markus 1286: {
1.117 markus 1287: Identity *id;
1.51 markus 1288:
1.214 djm 1289: if (authctxt->agent_fd != -1)
1290: ssh_close_authentication_socket(authctxt->agent_fd);
1.117 markus 1291: for (id = TAILQ_FIRST(&authctxt->keys); id;
1292: id = TAILQ_FIRST(&authctxt->keys)) {
1293: TAILQ_REMOVE(&authctxt->keys, id, next);
1294: if (id->key)
1.214 djm 1295: sshkey_free(id->key);
1.197 djm 1296: free(id->filename);
1297: free(id);
1.117 markus 1298: }
1.1 markus 1299: }
1300:
1.20 markus 1301: int
1302: userauth_pubkey(Authctxt *authctxt)
1303: {
1.117 markus 1304: Identity *id;
1.20 markus 1305: int sent = 0;
1306:
1.117 markus 1307: while ((id = TAILQ_FIRST(&authctxt->keys))) {
1308: if (id->tried++)
1309: return (0);
1.127 markus 1310: /* move key to the end of the queue */
1.117 markus 1311: TAILQ_REMOVE(&authctxt->keys, id, next);
1312: TAILQ_INSERT_TAIL(&authctxt->keys, id, next);
1313: /*
1314: * send a test message if we have the public key. for
1315: * encrypted keys we cannot do this and have to load the
1316: * private key instead
1317: */
1.200 djm 1318: if (id->key != NULL) {
1319: if (key_type_plain(id->key->type) == KEY_RSA &&
1320: (datafellows & SSH_BUG_RSASIGMD5) != 0) {
1321: debug("Skipped %s key %s for RSA/MD5 server",
1322: key_type(id->key), id->filename);
1323: } else if (id->key->type != KEY_RSA1) {
1324: debug("Offering %s public key: %s",
1325: key_type(id->key), id->filename);
1326: sent = send_pubkey_test(authctxt, id);
1327: }
1328: } else {
1.117 markus 1329: debug("Trying private key: %s", id->filename);
1.191 dtucker 1330: id->key = load_identity_file(id->filename,
1331: id->userprovided);
1.117 markus 1332: if (id->key != NULL) {
1333: id->isprivate = 1;
1.200 djm 1334: if (key_type_plain(id->key->type) == KEY_RSA &&
1335: (datafellows & SSH_BUG_RSASIGMD5) != 0) {
1336: debug("Skipped %s key %s for RSA/MD5 "
1337: "server", key_type(id->key),
1338: id->filename);
1339: } else {
1340: sent = sign_and_send_pubkey(
1341: authctxt, id);
1342: }
1.117 markus 1343: key_free(id->key);
1344: id->key = NULL;
1.51 markus 1345: }
1346: }
1.117 markus 1347: if (sent)
1348: return (sent);
1.28 markus 1349: }
1.117 markus 1350: return (0);
1.20 markus 1351: }
1352:
1.23 markus 1353: /*
1354: * Send userauth request message specifying keyboard-interactive method.
1355: */
1356: int
1357: userauth_kbdint(Authctxt *authctxt)
1358: {
1359: static int attempt = 0;
1360:
1361: if (attempt++ >= options.number_of_password_prompts)
1362: return 0;
1.82 markus 1363: /* disable if no SSH2_MSG_USERAUTH_INFO_REQUEST has been seen */
1364: if (attempt > 1 && !authctxt->info_req_seen) {
1365: debug3("userauth_kbdint: disable: no info_req_seen");
1366: dispatch_set(SSH2_MSG_USERAUTH_INFO_REQUEST, NULL);
1367: return 0;
1368: }
1.23 markus 1369:
1370: debug2("userauth_kbdint");
1371: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1372: packet_put_cstring(authctxt->server_user);
1373: packet_put_cstring(authctxt->service);
1374: packet_put_cstring(authctxt->method->name);
1375: packet_put_cstring(""); /* lang */
1376: packet_put_cstring(options.kbd_interactive_devices ?
1377: options.kbd_interactive_devices : "");
1378: packet_send();
1379:
1380: dispatch_set(SSH2_MSG_USERAUTH_INFO_REQUEST, &input_userauth_info_req);
1381: return 1;
1382: }
1383:
1384: /*
1.46 markus 1385: * parse INFO_REQUEST, prompt user and send INFO_RESPONSE
1.23 markus 1386: */
1.218 markus 1387: int
1.92 markus 1388: input_userauth_info_req(int type, u_int32_t seq, void *ctxt)
1.23 markus 1389: {
1390: Authctxt *authctxt = ctxt;
1.46 markus 1391: char *name, *inst, *lang, *prompt, *response;
1.32 markus 1392: u_int num_prompts, i;
1.23 markus 1393: int echo = 0;
1394:
1395: debug2("input_userauth_info_req");
1396:
1397: if (authctxt == NULL)
1398: fatal("input_userauth_info_req: no authentication context");
1.82 markus 1399:
1400: authctxt->info_req_seen = 1;
1.23 markus 1401:
1402: name = packet_get_string(NULL);
1403: inst = packet_get_string(NULL);
1404: lang = packet_get_string(NULL);
1405: if (strlen(name) > 0)
1.116 itojun 1406: logit("%s", name);
1.23 markus 1407: if (strlen(inst) > 0)
1.116 itojun 1408: logit("%s", inst);
1.197 djm 1409: free(name);
1410: free(inst);
1411: free(lang);
1.23 markus 1412:
1413: num_prompts = packet_get_int();
1414: /*
1415: * Begin to build info response packet based on prompts requested.
1416: * We commit to providing the correct number of responses, so if
1417: * further on we run into a problem that prevents this, we have to
1418: * be sure and clean this up and send a correct error response.
1419: */
1420: packet_start(SSH2_MSG_USERAUTH_INFO_RESPONSE);
1421: packet_put_int(num_prompts);
1422:
1.73 markus 1423: debug2("input_userauth_info_req: num_prompts %d", num_prompts);
1.23 markus 1424: for (i = 0; i < num_prompts; i++) {
1425: prompt = packet_get_string(NULL);
1426: echo = packet_get_char();
1427:
1.77 markus 1428: response = read_passphrase(prompt, echo ? RP_ECHO : 0);
1.23 markus 1429:
1.49 markus 1430: packet_put_cstring(response);
1.204 djm 1431: explicit_bzero(response, strlen(response));
1.197 djm 1432: free(response);
1433: free(prompt);
1.23 markus 1434: }
1.90 markus 1435: packet_check_eom(); /* done with parsing incoming message. */
1.23 markus 1436:
1.85 markus 1437: packet_add_padding(64);
1.23 markus 1438: packet_send();
1.218 markus 1439: return 0;
1.68 markus 1440: }
1441:
1.100 markus 1442: static int
1.105 deraadt 1443: ssh_keysign(Key *key, u_char **sigp, u_int *lenp,
1.100 markus 1444: u_char *data, u_int datalen)
1445: {
1446: Buffer b;
1.101 markus 1447: struct stat st;
1.100 markus 1448: pid_t pid;
1.103 markus 1449: int to[2], from[2], status, version = 2;
1.100 markus 1450:
1.109 markus 1451: debug2("ssh_keysign called");
1.100 markus 1452:
1.101 markus 1453: if (stat(_PATH_SSH_KEY_SIGN, &st) < 0) {
1.179 dtucker 1454: error("ssh_keysign: not installed: %s", strerror(errno));
1.101 markus 1455: return -1;
1456: }
1.100 markus 1457: if (fflush(stdout) != 0)
1458: error("ssh_keysign: fflush: %s", strerror(errno));
1459: if (pipe(to) < 0) {
1460: error("ssh_keysign: pipe: %s", strerror(errno));
1461: return -1;
1462: }
1463: if (pipe(from) < 0) {
1464: error("ssh_keysign: pipe: %s", strerror(errno));
1465: return -1;
1466: }
1467: if ((pid = fork()) < 0) {
1468: error("ssh_keysign: fork: %s", strerror(errno));
1469: return -1;
1470: }
1471: if (pid == 0) {
1.174 dtucker 1472: /* keep the socket on exec */
1473: fcntl(packet_get_connection_in(), F_SETFD, 0);
1.155 markus 1474: permanently_drop_suid(getuid());
1.100 markus 1475: close(from[0]);
1476: if (dup2(from[1], STDOUT_FILENO) < 0)
1477: fatal("ssh_keysign: dup2: %s", strerror(errno));
1478: close(to[1]);
1479: if (dup2(to[0], STDIN_FILENO) < 0)
1480: fatal("ssh_keysign: dup2: %s", strerror(errno));
1.103 markus 1481: close(from[1]);
1482: close(to[0]);
1.102 markus 1483: execl(_PATH_SSH_KEY_SIGN, _PATH_SSH_KEY_SIGN, (char *) 0);
1.100 markus 1484: fatal("ssh_keysign: exec(%s): %s", _PATH_SSH_KEY_SIGN,
1485: strerror(errno));
1486: }
1487: close(from[1]);
1488: close(to[0]);
1489:
1490: buffer_init(&b);
1.103 markus 1491: buffer_put_int(&b, packet_get_connection_in()); /* send # of socket */
1.100 markus 1492: buffer_put_string(&b, data, datalen);
1.131 djm 1493: if (ssh_msg_send(to[1], version, &b) == -1)
1494: fatal("ssh_keysign: couldn't send request");
1.100 markus 1495:
1.110 djm 1496: if (ssh_msg_recv(from[0], &b) < 0) {
1.101 markus 1497: error("ssh_keysign: no reply");
1.134 markus 1498: buffer_free(&b);
1.100 markus 1499: return -1;
1500: }
1.101 markus 1501: close(from[0]);
1502: close(to[1]);
1503:
1.103 markus 1504: while (waitpid(pid, &status, 0) < 0)
1505: if (errno != EINTR)
1506: break;
1.101 markus 1507:
1.100 markus 1508: if (buffer_get_char(&b) != version) {
1.101 markus 1509: error("ssh_keysign: bad version");
1.134 markus 1510: buffer_free(&b);
1.100 markus 1511: return -1;
1512: }
1513: *sigp = buffer_get_string(&b, lenp);
1.134 markus 1514: buffer_free(&b);
1.100 markus 1515:
1516: return 0;
1517: }
1518:
1.68 markus 1519: int
1520: userauth_hostbased(Authctxt *authctxt)
1521: {
1522: Key *private = NULL;
1.100 markus 1523: Sensitive *sensitive = authctxt->sensitive;
1.68 markus 1524: Buffer b;
1525: u_char *signature, *blob;
1.179 dtucker 1526: char *chost, *pkalg, *p;
1.72 markus 1527: const char *service;
1.68 markus 1528: u_int blen, slen;
1.176 dtucker 1529: int ok, i, found = 0;
1.213 djm 1530:
1531: /* XXX provide some way to allow user to specify key types attempted */
1.68 markus 1532:
1533: /* check for a useful key */
1.100 markus 1534: for (i = 0; i < sensitive->nkeys; i++) {
1535: private = sensitive->keys[i];
1.68 markus 1536: if (private && private->type != KEY_RSA1) {
1537: found = 1;
1538: /* we take and free the key */
1.100 markus 1539: sensitive->keys[i] = NULL;
1.68 markus 1540: break;
1541: }
1542: }
1543: if (!found) {
1.109 markus 1544: debug("No more client hostkeys for hostbased authentication.");
1.68 markus 1545: return 0;
1546: }
1.211 djm 1547:
1548: debug("%s: trying hostkey type %s", __func__, key_type(private));
1549:
1.68 markus 1550: if (key_to_blob(private, &blob, &blen) == 0) {
1551: key_free(private);
1552: return 0;
1553: }
1.211 djm 1554:
1.84 markus 1555: /* figure out a name for the client host */
1.179 dtucker 1556: p = get_local_name(packet_get_connection_in());
1.84 markus 1557: if (p == NULL) {
1558: error("userauth_hostbased: cannot get local ipaddr/name");
1559: key_free(private);
1.197 djm 1560: free(blob);
1.84 markus 1561: return 0;
1562: }
1.150 djm 1563: xasprintf(&chost, "%s.", p);
1.84 markus 1564: debug2("userauth_hostbased: chost %s", chost);
1.197 djm 1565: free(p);
1.84 markus 1566:
1.72 markus 1567: service = datafellows & SSH_BUG_HBSERVICE ? "ssh-userauth" :
1568: authctxt->service;
1.68 markus 1569: pkalg = xstrdup(key_ssh_name(private));
1570: buffer_init(&b);
1571: /* construct data */
1.72 markus 1572: buffer_put_string(&b, session_id2, session_id2_len);
1.68 markus 1573: buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
1574: buffer_put_cstring(&b, authctxt->server_user);
1.72 markus 1575: buffer_put_cstring(&b, service);
1.68 markus 1576: buffer_put_cstring(&b, authctxt->method->name);
1577: buffer_put_cstring(&b, pkalg);
1578: buffer_put_string(&b, blob, blen);
1579: buffer_put_cstring(&b, chost);
1580: buffer_put_cstring(&b, authctxt->local_user);
1581: #ifdef DEBUG_PK
1582: buffer_dump(&b);
1583: #endif
1.100 markus 1584: if (sensitive->external_keysign)
1585: ok = ssh_keysign(private, &signature, &slen,
1586: buffer_ptr(&b), buffer_len(&b));
1587: else
1588: ok = key_sign(private, &signature, &slen,
1589: buffer_ptr(&b), buffer_len(&b));
1.68 markus 1590: key_free(private);
1591: buffer_free(&b);
1592: if (ok != 0) {
1593: error("key_sign failed");
1.197 djm 1594: free(chost);
1595: free(pkalg);
1596: free(blob);
1.68 markus 1597: return 0;
1598: }
1599: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1600: packet_put_cstring(authctxt->server_user);
1601: packet_put_cstring(authctxt->service);
1602: packet_put_cstring(authctxt->method->name);
1603: packet_put_cstring(pkalg);
1604: packet_put_string(blob, blen);
1605: packet_put_cstring(chost);
1606: packet_put_cstring(authctxt->local_user);
1607: packet_put_string(signature, slen);
1.204 djm 1608: explicit_bzero(signature, slen);
1.197 djm 1609: free(signature);
1610: free(chost);
1611: free(pkalg);
1612: free(blob);
1.68 markus 1613:
1614: packet_send();
1615: return 1;
1.23 markus 1616: }
1.170 djm 1617:
1.20 markus 1618: /* find auth method */
1619:
1620: /*
1621: * given auth method name, if configurable options permit this method fill
1622: * in auth_ident field and return true, otherwise return false.
1623: */
1.76 itojun 1624: static int
1.20 markus 1625: authmethod_is_enabled(Authmethod *method)
1626: {
1627: if (method == NULL)
1628: return 0;
1629: /* return false if options indicate this method is disabled */
1630: if (method->enabled == NULL || *method->enabled == 0)
1631: return 0;
1632: /* return false if batch mode is enabled but method needs interactive mode */
1633: if (method->batch_flag != NULL && *method->batch_flag != 0)
1634: return 0;
1635: return 1;
1636: }
1637:
1.76 itojun 1638: static Authmethod *
1.20 markus 1639: authmethod_lookup(const char *name)
1.1 markus 1640: {
1.20 markus 1641: Authmethod *method = NULL;
1642: if (name != NULL)
1643: for (method = authmethods; method->name != NULL; method++)
1644: if (strcmp(name, method->name) == 0)
1645: return method;
1646: debug2("Unrecognized authentication method name: %s", name ? name : "NULL");
1647: return NULL;
1648: }
1.1 markus 1649:
1.53 markus 1650: /* XXX internal state */
1651: static Authmethod *current = NULL;
1652: static char *supported = NULL;
1653: static char *preferred = NULL;
1.105 deraadt 1654:
1.20 markus 1655: /*
1656: * Given the authentication method list sent by the server, return the
1657: * next method we should try. If the server initially sends a nil list,
1.67 markus 1658: * use a built-in default list.
1.41 stevesk 1659: */
1.76 itojun 1660: static Authmethod *
1.20 markus 1661: authmethod_get(char *authlist)
1662: {
1.53 markus 1663: char *name = NULL;
1.97 markus 1664: u_int next;
1.41 stevesk 1665:
1.20 markus 1666: /* Use a suitable default if we're passed a nil list. */
1667: if (authlist == NULL || strlen(authlist) == 0)
1.53 markus 1668: authlist = options.preferred_authentications;
1.20 markus 1669:
1.53 markus 1670: if (supported == NULL || strcmp(authlist, supported) != 0) {
1671: debug3("start over, passed a different list %s", authlist);
1.197 djm 1672: free(supported);
1.53 markus 1673: supported = xstrdup(authlist);
1674: preferred = options.preferred_authentications;
1675: debug3("preferred %s", preferred);
1676: current = NULL;
1677: } else if (current != NULL && authmethod_is_enabled(current))
1678: return current;
1.20 markus 1679:
1.53 markus 1680: for (;;) {
1681: if ((name = match_list(preferred, supported, &next)) == NULL) {
1.109 markus 1682: debug("No more authentication methods to try.");
1.53 markus 1683: current = NULL;
1684: return NULL;
1685: }
1686: preferred += next;
1.23 markus 1687: debug3("authmethod_lookup %s", name);
1.53 markus 1688: debug3("remaining preferred: %s", preferred);
1689: if ((current = authmethod_lookup(name)) != NULL &&
1690: authmethod_is_enabled(current)) {
1.23 markus 1691: debug3("authmethod_is_enabled %s", name);
1.109 markus 1692: debug("Next authentication method: %s", name);
1.197 djm 1693: free(name);
1.53 markus 1694: return current;
1.23 markus 1695: }
1.198 dtucker 1696: free(name);
1.1 markus 1697: }
1.53 markus 1698: }
1.1 markus 1699:
1.79 stevesk 1700: static char *
1.53 markus 1701: authmethods_get(void)
1702: {
1703: Authmethod *method = NULL;
1.93 markus 1704: Buffer b;
1705: char *list;
1.27 provos 1706:
1.93 markus 1707: buffer_init(&b);
1.53 markus 1708: for (method = authmethods; method->name != NULL; method++) {
1709: if (authmethod_is_enabled(method)) {
1.93 markus 1710: if (buffer_len(&b) > 0)
1711: buffer_append(&b, ",", 1);
1712: buffer_append(&b, method->name, strlen(method->name));
1.53 markus 1713: }
1714: }
1.93 markus 1715: buffer_append(&b, "\0", 1);
1716: list = xstrdup(buffer_ptr(&b));
1717: buffer_free(&b);
1718: return list;
1.1 markus 1719: }
1.170 djm 1720:
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