Annotation of src/usr.bin/ssh/sshconnect2.c, Revision 1.221
1.221 ! markus 1: /* $OpenBSD: sshconnect2.c,v 1.220 2015/01/20 07:56:44 djm Exp $ */
1.1 markus 2: /*
3: * Copyright (c) 2000 Markus Friedl. All rights reserved.
1.170 djm 4: * Copyright (c) 2008 Damien Miller. All rights reserved.
1.1 markus 5: *
6: * Redistribution and use in source and binary forms, with or without
7: * modification, are permitted provided that the following conditions
8: * are met:
9: * 1. Redistributions of source code must retain the above copyright
10: * notice, this list of conditions and the following disclaimer.
11: * 2. Redistributions in binary form must reproduce the above copyright
12: * notice, this list of conditions and the following disclaimer in the
13: * documentation and/or other materials provided with the distribution.
14: *
15: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25: */
26:
1.145 stevesk 27: #include <sys/types.h>
1.160 deraadt 28: #include <sys/socket.h>
1.145 stevesk 29: #include <sys/wait.h>
1.144 stevesk 30: #include <sys/queue.h>
1.146 stevesk 31: #include <sys/stat.h>
1.156 stevesk 32:
33: #include <errno.h>
1.174 dtucker 34: #include <fcntl.h>
1.164 jolan 35: #include <netdb.h>
1.159 stevesk 36: #include <stdio.h>
1.158 stevesk 37: #include <string.h>
1.160 deraadt 38: #include <signal.h>
39: #include <pwd.h>
1.157 stevesk 40: #include <unistd.h>
1.166 djm 41: #include <vis.h>
1.1 markus 42:
1.160 deraadt 43: #include "xmalloc.h"
1.1 markus 44: #include "ssh.h"
1.37 markus 45: #include "ssh2.h"
1.1 markus 46: #include "buffer.h"
47: #include "packet.h"
48: #include "compat.h"
1.37 markus 49: #include "cipher.h"
1.160 deraadt 50: #include "key.h"
1.1 markus 51: #include "kex.h"
52: #include "myproposal.h"
53: #include "sshconnect.h"
54: #include "authfile.h"
1.57 provos 55: #include "dh.h"
1.17 markus 56: #include "authfd.h"
1.37 markus 57: #include "log.h"
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;
1.221 ! markus 155: int r;
1.61 markus 156:
157: xxx_host = host;
158: xxx_hostaddr = hostaddr;
1.22 provos 159:
1.29 markus 160: if (options.ciphers == (char *)-1) {
1.116 itojun 161: logit("No valid ciphers for protocol version 2 given, using defaults.");
1.29 markus 162: options.ciphers = NULL;
1.24 markus 163: }
1.22 provos 164: if (options.ciphers != NULL) {
165: myproposal[PROPOSAL_ENC_ALGS_CTOS] =
166: myproposal[PROPOSAL_ENC_ALGS_STOC] = options.ciphers;
167: }
1.60 stevesk 168: myproposal[PROPOSAL_ENC_ALGS_CTOS] =
169: compat_cipher_proposal(myproposal[PROPOSAL_ENC_ALGS_CTOS]);
170: myproposal[PROPOSAL_ENC_ALGS_STOC] =
171: compat_cipher_proposal(myproposal[PROPOSAL_ENC_ALGS_STOC]);
1.22 provos 172: if (options.compression) {
1.47 markus 173: myproposal[PROPOSAL_COMP_ALGS_CTOS] =
1.141 markus 174: myproposal[PROPOSAL_COMP_ALGS_STOC] = "zlib@openssh.com,zlib,none";
1.22 provos 175: } else {
1.47 markus 176: myproposal[PROPOSAL_COMP_ALGS_CTOS] =
1.141 markus 177: myproposal[PROPOSAL_COMP_ALGS_STOC] = "none,zlib@openssh.com,zlib";
1.47 markus 178: }
179: if (options.macs != NULL) {
180: myproposal[PROPOSAL_MAC_ALGS_CTOS] =
181: myproposal[PROPOSAL_MAC_ALGS_STOC] = options.macs;
1.22 provos 182: }
1.70 markus 183: if (options.hostkeyalgorithms != NULL)
1.88 deraadt 184: myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] =
1.200 djm 185: compat_pkalg_proposal(options.hostkeyalgorithms);
1.186 djm 186: else {
187: /* Prefer algorithms that we already have keys for */
188: myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] =
1.200 djm 189: compat_pkalg_proposal(
190: order_hostkeyalgs(host, hostaddr, port));
1.186 djm 191: }
1.185 djm 192: if (options.kex_algorithms != NULL)
193: myproposal[PROPOSAL_KEX_ALGS] = options.kex_algorithms;
1.206 djm 194: myproposal[PROPOSAL_KEX_ALGS] = compat_kex_proposal(
195: myproposal[PROPOSAL_KEX_ALGS]);
1.115 markus 196:
1.196 dtucker 197: if (options.rekey_limit || options.rekey_interval)
198: packet_set_rekey_limits((u_int32_t)options.rekey_limit,
199: (time_t)options.rekey_interval);
1.22 provos 200:
1.65 markus 201: /* start key exchange */
1.221 ! markus 202: if ((r = kex_setup(active_state, myproposal)) != 0)
! 203: fatal("kex_setup: %s", ssh_err(r));
1.219 markus 204: kex = active_state->kex;
1.207 markus 205: #ifdef WITH_OPENSSL
1.111 markus 206: kex->kex[KEX_DH_GRP1_SHA1] = kexdh_client;
1.138 djm 207: kex->kex[KEX_DH_GRP14_SHA1] = kexdh_client;
1.111 markus 208: kex->kex[KEX_DH_GEX_SHA1] = kexgex_client;
1.147 djm 209: kex->kex[KEX_DH_GEX_SHA256] = kexgex_client;
1.184 djm 210: kex->kex[KEX_ECDH_SHA2] = kexecdh_client;
1.207 markus 211: #endif
1.199 markus 212: kex->kex[KEX_C25519_SHA256] = kexc25519_client;
1.61 markus 213: kex->client_version_string=client_version_string;
214: kex->server_version_string=server_version_string;
1.75 markus 215: kex->verify_host_key=&verify_host_key_callback;
1.22 provos 216:
1.219 markus 217: dispatch_run(DISPATCH_BLOCK, &kex->done, active_state);
1.173 andreas 218:
219: if (options.use_roaming && !kex->roaming) {
220: debug("Roaming not allowed by server");
221: options.use_roaming = 0;
222: }
1.62 markus 223:
224: session_id2 = kex->session_id;
225: session_id2_len = kex->session_id_len;
1.22 provos 226:
227: #ifdef DEBUG_KEXDH
228: /* send 1st encrypted/maced/compressed message */
229: packet_start(SSH2_MSG_IGNORE);
230: packet_put_cstring("markus");
231: packet_send();
232: packet_write_wait();
233: #endif
1.1 markus 234: }
1.11 markus 235:
1.1 markus 236: /*
237: * Authenticate user
238: */
1.20 markus 239:
1.214 djm 240: typedef struct cauthctxt Authctxt;
241: typedef struct cauthmethod Authmethod;
1.117 markus 242: typedef struct identity Identity;
243: typedef struct idlist Idlist;
1.20 markus 244:
1.117 markus 245: struct identity {
246: TAILQ_ENTRY(identity) next;
1.214 djm 247: int agent_fd; /* >=0 if agent supports key */
248: struct sshkey *key; /* public/private key */
1.117 markus 249: char *filename; /* comment for agent-only keys */
250: int tried;
251: int isprivate; /* key points to the private key */
1.191 dtucker 252: int userprovided;
1.117 markus 253: };
254: TAILQ_HEAD(idlist, identity);
1.20 markus 255:
1.214 djm 256: struct cauthctxt {
1.20 markus 257: const char *server_user;
1.68 markus 258: const char *local_user;
1.20 markus 259: const char *host;
260: const char *service;
1.214 djm 261: struct cauthmethod *method;
1.183 djm 262: sig_atomic_t success;
1.51 markus 263: char *authlist;
1.214 djm 264: int attempt;
1.68 markus 265: /* pubkey */
1.214 djm 266: struct idlist keys;
267: int agent_fd;
1.68 markus 268: /* hostbased */
1.100 markus 269: Sensitive *sensitive;
1.82 markus 270: /* kbd-interactive */
271: int info_req_seen;
1.121 markus 272: /* generic */
273: void *methoddata;
1.20 markus 274: };
1.214 djm 275:
276: struct cauthmethod {
1.20 markus 277: char *name; /* string to compare against server's list */
278: int (*userauth)(Authctxt *authctxt);
1.170 djm 279: void (*cleanup)(Authctxt *authctxt);
1.20 markus 280: int *enabled; /* flag in option struct that enables method */
281: int *batch_flag; /* flag in option struct that disables method */
282: };
283:
1.218 markus 284: int input_userauth_success(int, u_int32_t, void *);
285: int input_userauth_success_unexpected(int, u_int32_t, void *);
286: int input_userauth_failure(int, u_int32_t, void *);
287: int input_userauth_banner(int, u_int32_t, void *);
288: int input_userauth_error(int, u_int32_t, void *);
289: int input_userauth_info_req(int, u_int32_t, void *);
290: int input_userauth_pk_ok(int, u_int32_t, void *);
291: int input_userauth_passwd_changereq(int, u_int32_t, void *);
1.86 itojun 292:
293: int userauth_none(Authctxt *);
294: int userauth_pubkey(Authctxt *);
295: int userauth_passwd(Authctxt *);
296: int userauth_kbdint(Authctxt *);
297: int userauth_hostbased(Authctxt *);
1.20 markus 298:
1.121 markus 299: #ifdef GSSAPI
300: int userauth_gssapi(Authctxt *authctxt);
1.218 markus 301: int input_gssapi_response(int type, u_int32_t, void *);
302: int input_gssapi_token(int type, u_int32_t, void *);
303: int input_gssapi_hash(int type, u_int32_t, void *);
304: int input_gssapi_error(int, u_int32_t, void *);
305: int input_gssapi_errtok(int, u_int32_t, void *);
1.121 markus 306: #endif
307:
1.86 itojun 308: void userauth(Authctxt *, char *);
1.51 markus 309:
1.117 markus 310: static int sign_and_send_pubkey(Authctxt *, Identity *);
311: static void pubkey_prepare(Authctxt *);
312: static void pubkey_cleanup(Authctxt *);
1.191 dtucker 313: static Key *load_identity_file(char *, int);
1.76 itojun 314:
315: static Authmethod *authmethod_get(char *authlist);
316: static Authmethod *authmethod_lookup(const char *name);
317: static char *authmethods_get(void);
1.20 markus 318:
319: Authmethod authmethods[] = {
1.121 markus 320: #ifdef GSSAPI
1.132 markus 321: {"gssapi-with-mic",
1.121 markus 322: userauth_gssapi,
1.170 djm 323: NULL,
1.121 markus 324: &options.gss_authentication,
325: NULL},
326: #endif
1.81 markus 327: {"hostbased",
328: userauth_hostbased,
1.170 djm 329: NULL,
1.81 markus 330: &options.hostbased_authentication,
331: NULL},
1.20 markus 332: {"publickey",
333: userauth_pubkey,
1.170 djm 334: NULL,
1.28 markus 335: &options.pubkey_authentication,
1.20 markus 336: NULL},
1.81 markus 337: {"keyboard-interactive",
338: userauth_kbdint,
1.170 djm 339: NULL,
1.81 markus 340: &options.kbd_interactive_authentication,
341: &options.batch_mode},
1.20 markus 342: {"password",
343: userauth_passwd,
1.170 djm 344: NULL,
1.20 markus 345: &options.password_authentication,
1.23 markus 346: &options.batch_mode},
347: {"none",
348: userauth_none,
349: NULL,
1.170 djm 350: NULL,
1.23 markus 351: NULL},
1.170 djm 352: {NULL, NULL, NULL, NULL, NULL}
1.20 markus 353: };
354:
355: void
1.68 markus 356: ssh_userauth2(const char *local_user, const char *server_user, char *host,
1.100 markus 357: Sensitive *sensitive)
1.20 markus 358: {
359: Authctxt authctxt;
360: int type;
1.39 markus 361:
1.73 markus 362: if (options.challenge_response_authentication)
1.39 markus 363: options.kbd_interactive_authentication = 1;
1.20 markus 364:
365: packet_start(SSH2_MSG_SERVICE_REQUEST);
366: packet_put_cstring("ssh-userauth");
367: packet_send();
1.108 markus 368: debug("SSH2_MSG_SERVICE_REQUEST sent");
1.20 markus 369: packet_write_wait();
1.91 markus 370: type = packet_read();
1.108 markus 371: if (type != SSH2_MSG_SERVICE_ACCEPT)
372: fatal("Server denied authentication request: %d", type);
1.20 markus 373: if (packet_remaining() > 0) {
1.91 markus 374: char *reply = packet_get_string(NULL);
1.108 markus 375: debug2("service_accept: %s", reply);
1.197 djm 376: free(reply);
1.20 markus 377: } else {
1.109 markus 378: debug2("buggy server: service_accept w/o service");
1.20 markus 379: }
1.90 markus 380: packet_check_eom();
1.108 markus 381: debug("SSH2_MSG_SERVICE_ACCEPT received");
1.20 markus 382:
1.53 markus 383: if (options.preferred_authentications == NULL)
384: options.preferred_authentications = authmethods_get();
385:
1.20 markus 386: /* setup authentication context */
1.82 markus 387: memset(&authctxt, 0, sizeof(authctxt));
1.117 markus 388: pubkey_prepare(&authctxt);
1.20 markus 389: authctxt.server_user = server_user;
1.68 markus 390: authctxt.local_user = local_user;
1.20 markus 391: authctxt.host = host;
392: authctxt.service = "ssh-connection"; /* service name */
393: authctxt.success = 0;
1.23 markus 394: authctxt.method = authmethod_lookup("none");
1.51 markus 395: authctxt.authlist = NULL;
1.121 markus 396: authctxt.methoddata = NULL;
1.100 markus 397: authctxt.sensitive = sensitive;
1.82 markus 398: authctxt.info_req_seen = 0;
1.215 djm 399: authctxt.agent_fd = -1;
1.23 markus 400: if (authctxt.method == NULL)
401: fatal("ssh_userauth2: internal error: cannot send userauth none request");
1.20 markus 402:
403: /* initial userauth request */
1.23 markus 404: userauth_none(&authctxt);
1.20 markus 405:
1.65 markus 406: dispatch_init(&input_userauth_error);
1.20 markus 407: dispatch_set(SSH2_MSG_USERAUTH_SUCCESS, &input_userauth_success);
408: dispatch_set(SSH2_MSG_USERAUTH_FAILURE, &input_userauth_failure);
1.35 markus 409: dispatch_set(SSH2_MSG_USERAUTH_BANNER, &input_userauth_banner);
1.20 markus 410: dispatch_run(DISPATCH_BLOCK, &authctxt.success, &authctxt); /* loop until success */
411:
1.117 markus 412: pubkey_cleanup(&authctxt);
1.119 markus 413: dispatch_range(SSH2_MSG_USERAUTH_MIN, SSH2_MSG_USERAUTH_MAX, NULL);
414:
1.109 markus 415: debug("Authentication succeeded (%s).", authctxt.method->name);
1.20 markus 416: }
1.119 markus 417:
1.20 markus 418: void
1.51 markus 419: userauth(Authctxt *authctxt, char *authlist)
420: {
1.170 djm 421: if (authctxt->method != NULL && authctxt->method->cleanup != NULL)
422: authctxt->method->cleanup(authctxt);
423:
1.197 djm 424: free(authctxt->methoddata);
425: authctxt->methoddata = NULL;
1.51 markus 426: if (authlist == NULL) {
427: authlist = authctxt->authlist;
428: } else {
1.197 djm 429: free(authctxt->authlist);
1.51 markus 430: authctxt->authlist = authlist;
431: }
432: for (;;) {
433: Authmethod *method = authmethod_get(authlist);
434: if (method == NULL)
435: fatal("Permission denied (%s).", authlist);
436: authctxt->method = method;
1.119 markus 437:
438: /* reset the per method handler */
439: dispatch_range(SSH2_MSG_USERAUTH_PER_METHOD_MIN,
440: SSH2_MSG_USERAUTH_PER_METHOD_MAX, NULL);
441:
442: /* and try new method */
1.51 markus 443: if (method->userauth(authctxt) != 0) {
444: debug2("we sent a %s packet, wait for reply", method->name);
445: break;
446: } else {
447: debug2("we did not send a packet, disable method");
448: method->enabled = NULL;
449: }
450: }
451: }
1.105 deraadt 452:
1.169 djm 453: /* ARGSUSED */
1.218 markus 454: int
1.92 markus 455: input_userauth_error(int type, u_int32_t seq, void *ctxt)
1.20 markus 456: {
1.35 markus 457: fatal("input_userauth_error: bad message during authentication: "
1.140 djm 458: "type %d", type);
1.218 markus 459: return 0;
1.35 markus 460: }
1.105 deraadt 461:
1.169 djm 462: /* ARGSUSED */
1.218 markus 463: int
1.92 markus 464: input_userauth_banner(int type, u_int32_t seq, void *ctxt)
1.35 markus 465: {
1.166 djm 466: char *msg, *raw, *lang;
467: u_int len;
1.126 deraadt 468:
1.35 markus 469: debug3("input_userauth_banner");
1.166 djm 470: raw = packet_get_string(&len);
1.35 markus 471: lang = packet_get_string(NULL);
1.167 markus 472: if (len > 0 && options.log_level >= SYSLOG_LEVEL_INFO) {
1.166 djm 473: if (len > 65536)
474: len = 65536;
1.168 deraadt 475: msg = xmalloc(len * 4 + 1); /* max expansion from strnvis() */
1.177 dtucker 476: strnvis(msg, raw, len * 4 + 1, VIS_SAFE|VIS_OCTAL|VIS_NOSLASH);
1.125 dtucker 477: fprintf(stderr, "%s", msg);
1.197 djm 478: free(msg);
1.166 djm 479: }
1.197 djm 480: free(raw);
481: free(lang);
1.218 markus 482: return 0;
1.20 markus 483: }
1.105 deraadt 484:
1.169 djm 485: /* ARGSUSED */
1.218 markus 486: int
1.92 markus 487: input_userauth_success(int type, u_int32_t seq, void *ctxt)
1.20 markus 488: {
489: Authctxt *authctxt = ctxt;
1.172 djm 490:
1.20 markus 491: if (authctxt == NULL)
492: fatal("input_userauth_success: no authentication context");
1.197 djm 493: free(authctxt->authlist);
494: authctxt->authlist = NULL;
1.172 djm 495: if (authctxt->method != NULL && authctxt->method->cleanup != NULL)
496: authctxt->method->cleanup(authctxt);
1.197 djm 497: free(authctxt->methoddata);
498: authctxt->methoddata = NULL;
1.20 markus 499: authctxt->success = 1; /* break out */
1.218 markus 500: return 0;
1.20 markus 501: }
1.105 deraadt 502:
1.218 markus 503: int
1.172 djm 504: input_userauth_success_unexpected(int type, u_int32_t seq, void *ctxt)
505: {
506: Authctxt *authctxt = ctxt;
507:
508: if (authctxt == NULL)
509: fatal("%s: no authentication context", __func__);
510:
511: fatal("Unexpected authentication success during %s.",
512: authctxt->method->name);
1.218 markus 513: return 0;
1.172 djm 514: }
515:
1.169 djm 516: /* ARGSUSED */
1.218 markus 517: int
1.92 markus 518: input_userauth_failure(int type, u_int32_t seq, void *ctxt)
1.20 markus 519: {
520: Authctxt *authctxt = ctxt;
521: char *authlist = NULL;
522: int partial;
523:
524: if (authctxt == NULL)
525: fatal("input_userauth_failure: no authentication context");
526:
1.23 markus 527: authlist = packet_get_string(NULL);
1.20 markus 528: partial = packet_get_char();
1.90 markus 529: packet_check_eom();
1.20 markus 530:
1.193 markus 531: if (partial != 0) {
1.116 itojun 532: logit("Authenticated with partial success.");
1.193 markus 533: /* reset state */
534: pubkey_cleanup(authctxt);
535: pubkey_prepare(authctxt);
536: }
1.109 markus 537: debug("Authentications that can continue: %s", authlist);
1.20 markus 538:
1.51 markus 539: userauth(authctxt, authlist);
1.218 markus 540: return 0;
1.51 markus 541: }
1.169 djm 542:
543: /* ARGSUSED */
1.218 markus 544: int
1.92 markus 545: input_userauth_pk_ok(int type, u_int32_t seq, void *ctxt)
1.51 markus 546: {
547: Authctxt *authctxt = ctxt;
548: Key *key = NULL;
1.117 markus 549: Identity *id = NULL;
1.51 markus 550: Buffer b;
1.96 markus 551: int pktype, sent = 0;
552: u_int alen, blen;
553: char *pkalg, *fp;
554: u_char *pkblob;
1.51 markus 555:
556: if (authctxt == NULL)
557: fatal("input_userauth_pk_ok: no authentication context");
558: if (datafellows & SSH_BUG_PKOK) {
559: /* this is similar to SSH_BUG_PKAUTH */
560: debug2("input_userauth_pk_ok: SSH_BUG_PKOK");
561: pkblob = packet_get_string(&blen);
562: buffer_init(&b);
563: buffer_append(&b, pkblob, blen);
564: pkalg = buffer_get_string(&b, &alen);
565: buffer_free(&b);
566: } else {
567: pkalg = packet_get_string(&alen);
568: pkblob = packet_get_string(&blen);
569: }
1.90 markus 570: packet_check_eom();
1.51 markus 571:
1.117 markus 572: debug("Server accepts key: pkalg %s blen %u", pkalg, blen);
1.51 markus 573:
1.117 markus 574: if ((pktype = key_type_from_name(pkalg)) == KEY_UNSPEC) {
575: debug("unknown pkalg %s", pkalg);
576: goto done;
577: }
578: if ((key = key_from_blob(pkblob, blen)) == NULL) {
579: debug("no key from blob. pkalg %s", pkalg);
580: goto done;
581: }
582: if (key->type != pktype) {
583: error("input_userauth_pk_ok: type mismatch "
584: "for decoded key (received %d, expected %d)",
585: key->type, pktype);
586: goto done;
587: }
1.214 djm 588: fp = sshkey_fingerprint(key, options.fingerprint_hash, SSH_FP_DEFAULT);
1.117 markus 589: debug2("input_userauth_pk_ok: fp %s", fp);
1.197 djm 590: free(fp);
1.117 markus 591:
1.127 markus 592: /*
593: * search keys in the reverse order, because last candidate has been
594: * moved to the end of the queue. this also avoids confusion by
595: * duplicate keys
596: */
1.136 henning 597: TAILQ_FOREACH_REVERSE(id, &authctxt->keys, idlist, next) {
1.117 markus 598: if (key_equal(key, id->key)) {
599: sent = sign_and_send_pubkey(authctxt, id);
1.51 markus 600: break;
601: }
1.117 markus 602: }
603: done:
1.51 markus 604: if (key != NULL)
605: key_free(key);
1.197 djm 606: free(pkalg);
607: free(pkblob);
1.51 markus 608:
1.106 deraadt 609: /* try another method if we did not send a packet */
1.51 markus 610: if (sent == 0)
611: userauth(authctxt, NULL);
1.218 markus 612: return 0;
1.20 markus 613: }
1.121 markus 614:
615: #ifdef GSSAPI
1.133 djm 616: int
1.121 markus 617: userauth_gssapi(Authctxt *authctxt)
618: {
619: Gssctxt *gssctxt = NULL;
1.128 avsm 620: static gss_OID_set gss_supported = NULL;
1.139 djm 621: static u_int mech = 0;
1.121 markus 622: OM_uint32 min;
623: int ok = 0;
624:
625: /* Try one GSSAPI method at a time, rather than sending them all at
626: * once. */
627:
1.128 avsm 628: if (gss_supported == NULL)
629: gss_indicate_mechs(&min, &gss_supported);
1.121 markus 630:
631: /* Check to see if the mechanism is usable before we offer it */
1.128 avsm 632: while (mech < gss_supported->count && !ok) {
1.121 markus 633: /* My DER encoding requires length<128 */
1.128 avsm 634: if (gss_supported->elements[mech].length < 128 &&
1.161 djm 635: ssh_gssapi_check_mechanism(&gssctxt,
636: &gss_supported->elements[mech], authctxt->host)) {
1.121 markus 637: ok = 1; /* Mechanism works */
638: } else {
639: mech++;
640: }
641: }
642:
1.161 djm 643: if (!ok)
1.139 djm 644: return 0;
1.121 markus 645:
646: authctxt->methoddata=(void *)gssctxt;
647:
648: packet_start(SSH2_MSG_USERAUTH_REQUEST);
649: packet_put_cstring(authctxt->server_user);
650: packet_put_cstring(authctxt->service);
651: packet_put_cstring(authctxt->method->name);
652:
653: packet_put_int(1);
654:
1.129 markus 655: packet_put_int((gss_supported->elements[mech].length) + 2);
656: packet_put_char(SSH_GSS_OIDTYPE);
657: packet_put_char(gss_supported->elements[mech].length);
658: packet_put_raw(gss_supported->elements[mech].elements,
659: gss_supported->elements[mech].length);
1.121 markus 660:
661: packet_send();
662:
663: dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_RESPONSE, &input_gssapi_response);
664: dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_TOKEN, &input_gssapi_token);
665: dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERROR, &input_gssapi_error);
666: dispatch_set(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK, &input_gssapi_errtok);
667:
668: mech++; /* Move along to next candidate */
669:
670: return 1;
671: }
672:
1.130 markus 673: static OM_uint32
674: process_gssapi_token(void *ctxt, gss_buffer_t recv_tok)
675: {
676: Authctxt *authctxt = ctxt;
677: Gssctxt *gssctxt = authctxt->methoddata;
678: gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
1.142 djm 679: gss_buffer_desc mic = GSS_C_EMPTY_BUFFER;
680: gss_buffer_desc gssbuf;
1.132 markus 681: OM_uint32 status, ms, flags;
682: Buffer b;
1.133 djm 683:
1.130 markus 684: status = ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
1.132 markus 685: recv_tok, &send_tok, &flags);
1.130 markus 686:
687: if (send_tok.length > 0) {
688: if (GSS_ERROR(status))
689: packet_start(SSH2_MSG_USERAUTH_GSSAPI_ERRTOK);
690: else
691: packet_start(SSH2_MSG_USERAUTH_GSSAPI_TOKEN);
1.133 djm 692:
1.130 markus 693: packet_put_string(send_tok.value, send_tok.length);
694: packet_send();
695: gss_release_buffer(&ms, &send_tok);
696: }
1.133 djm 697:
1.130 markus 698: if (status == GSS_S_COMPLETE) {
1.132 markus 699: /* send either complete or MIC, depending on mechanism */
700: if (!(flags & GSS_C_INTEG_FLAG)) {
701: packet_start(SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE);
702: packet_send();
703: } else {
704: ssh_gssapi_buildmic(&b, authctxt->server_user,
705: authctxt->service, "gssapi-with-mic");
706:
707: gssbuf.value = buffer_ptr(&b);
708: gssbuf.length = buffer_len(&b);
1.133 djm 709:
1.132 markus 710: status = ssh_gssapi_sign(gssctxt, &gssbuf, &mic);
1.133 djm 711:
1.132 markus 712: if (!GSS_ERROR(status)) {
713: packet_start(SSH2_MSG_USERAUTH_GSSAPI_MIC);
714: packet_put_string(mic.value, mic.length);
1.133 djm 715:
1.132 markus 716: packet_send();
717: }
1.133 djm 718:
1.132 markus 719: buffer_free(&b);
720: gss_release_buffer(&ms, &mic);
1.133 djm 721: }
1.130 markus 722: }
1.133 djm 723:
1.130 markus 724: return status;
725: }
726:
1.169 djm 727: /* ARGSUSED */
1.220 djm 728: int
1.121 markus 729: input_gssapi_response(int type, u_int32_t plen, void *ctxt)
730: {
731: Authctxt *authctxt = ctxt;
732: Gssctxt *gssctxt;
733: int oidlen;
734: char *oidv;
735:
736: if (authctxt == NULL)
737: fatal("input_gssapi_response: no authentication context");
738: gssctxt = authctxt->methoddata;
739:
740: /* Setup our OID */
741: oidv = packet_get_string(&oidlen);
742:
1.129 markus 743: if (oidlen <= 2 ||
744: oidv[0] != SSH_GSS_OIDTYPE ||
745: oidv[1] != oidlen - 2) {
1.197 djm 746: free(oidv);
1.129 markus 747: debug("Badly encoded mechanism OID received");
748: userauth(authctxt, NULL);
1.220 djm 749: return 0;
1.121 markus 750: }
1.129 markus 751:
752: if (!ssh_gssapi_check_oid(gssctxt, oidv + 2, oidlen - 2))
753: fatal("Server returned different OID than expected");
1.121 markus 754:
755: packet_check_eom();
756:
1.197 djm 757: free(oidv);
1.121 markus 758:
1.130 markus 759: if (GSS_ERROR(process_gssapi_token(ctxt, GSS_C_NO_BUFFER))) {
1.121 markus 760: /* Start again with next method on list */
761: debug("Trying to start again");
762: userauth(authctxt, NULL);
1.220 djm 763: return 0;
1.121 markus 764: }
1.220 djm 765: return 0;
1.121 markus 766: }
767:
1.169 djm 768: /* ARGSUSED */
1.220 djm 769: int
1.121 markus 770: input_gssapi_token(int type, u_int32_t plen, void *ctxt)
771: {
772: Authctxt *authctxt = ctxt;
773: gss_buffer_desc recv_tok;
1.130 markus 774: OM_uint32 status;
1.121 markus 775: u_int slen;
776:
777: if (authctxt == NULL)
778: fatal("input_gssapi_response: no authentication context");
779:
780: recv_tok.value = packet_get_string(&slen);
781: recv_tok.length = slen; /* safe typecast */
782:
783: packet_check_eom();
784:
1.130 markus 785: status = process_gssapi_token(ctxt, &recv_tok);
1.121 markus 786:
1.197 djm 787: free(recv_tok.value);
1.121 markus 788:
789: if (GSS_ERROR(status)) {
790: /* Start again with the next method in the list */
791: userauth(authctxt, NULL);
1.220 djm 792: return 0;
1.121 markus 793: }
1.220 djm 794: return 0;
1.121 markus 795: }
796:
1.169 djm 797: /* ARGSUSED */
1.220 djm 798: int
1.121 markus 799: input_gssapi_errtok(int type, u_int32_t plen, void *ctxt)
800: {
801: Authctxt *authctxt = ctxt;
802: Gssctxt *gssctxt;
803: gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
804: gss_buffer_desc recv_tok;
1.194 djm 805: OM_uint32 ms;
1.123 deraadt 806: u_int len;
1.121 markus 807:
808: if (authctxt == NULL)
809: fatal("input_gssapi_response: no authentication context");
810: gssctxt = authctxt->methoddata;
811:
1.123 deraadt 812: recv_tok.value = packet_get_string(&len);
813: recv_tok.length = len;
1.121 markus 814:
815: packet_check_eom();
816:
817: /* Stick it into GSSAPI and see what it says */
1.194 djm 818: (void)ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
1.140 djm 819: &recv_tok, &send_tok, NULL);
1.121 markus 820:
1.197 djm 821: free(recv_tok.value);
1.121 markus 822: gss_release_buffer(&ms, &send_tok);
823:
824: /* Server will be returning a failed packet after this one */
1.220 djm 825: return 0;
1.121 markus 826: }
827:
1.169 djm 828: /* ARGSUSED */
1.220 djm 829: int
1.121 markus 830: input_gssapi_error(int type, u_int32_t plen, void *ctxt)
831: {
832: char *msg;
833: char *lang;
834:
1.194 djm 835: /* maj */(void)packet_get_int();
836: /* min */(void)packet_get_int();
1.121 markus 837: msg=packet_get_string(NULL);
838: lang=packet_get_string(NULL);
839:
840: packet_check_eom();
841:
1.143 stevesk 842: debug("Server GSSAPI Error:\n%s", msg);
1.197 djm 843: free(msg);
844: free(lang);
1.220 djm 845: return 0;
1.121 markus 846: }
847: #endif /* GSSAPI */
1.20 markus 848:
1.1 markus 849: int
1.23 markus 850: userauth_none(Authctxt *authctxt)
851: {
852: /* initial userauth request */
853: packet_start(SSH2_MSG_USERAUTH_REQUEST);
854: packet_put_cstring(authctxt->server_user);
855: packet_put_cstring(authctxt->service);
856: packet_put_cstring(authctxt->method->name);
857: packet_send();
858: return 1;
859: }
860:
861: int
1.20 markus 862: userauth_passwd(Authctxt *authctxt)
1.1 markus 863: {
1.6 markus 864: static int attempt = 0;
1.99 markus 865: char prompt[150];
1.1 markus 866: char *password;
1.175 dtucker 867: const char *host = options.host_key_alias ? options.host_key_alias :
868: authctxt->host;
1.6 markus 869:
1.13 todd 870: if (attempt++ >= options.number_of_password_prompts)
1.6 markus 871: return 0;
1.13 todd 872:
1.87 deraadt 873: if (attempt != 1)
1.13 todd 874: error("Permission denied, please try again.");
1.1 markus 875:
1.43 itojun 876: snprintf(prompt, sizeof(prompt), "%.30s@%.128s's password: ",
1.175 dtucker 877: authctxt->server_user, host);
1.1 markus 878: password = read_passphrase(prompt, 0);
879: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1.20 markus 880: packet_put_cstring(authctxt->server_user);
881: packet_put_cstring(authctxt->service);
1.23 markus 882: packet_put_cstring(authctxt->method->name);
1.1 markus 883: packet_put_char(0);
1.49 markus 884: packet_put_cstring(password);
1.204 djm 885: explicit_bzero(password, strlen(password));
1.197 djm 886: free(password);
1.85 markus 887: packet_add_padding(64);
1.1 markus 888: packet_send();
1.99 markus 889:
1.104 deraadt 890: dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
1.99 markus 891: &input_userauth_passwd_changereq);
892:
1.1 markus 893: return 1;
894: }
1.169 djm 895:
1.99 markus 896: /*
897: * parse PASSWD_CHANGEREQ, prompt user and send SSH2_MSG_USERAUTH_REQUEST
898: */
1.169 djm 899: /* ARGSUSED */
1.218 markus 900: int
1.153 djm 901: input_userauth_passwd_changereq(int type, u_int32_t seqnr, void *ctxt)
1.99 markus 902: {
903: Authctxt *authctxt = ctxt;
904: char *info, *lang, *password = NULL, *retype = NULL;
905: char prompt[150];
1.175 dtucker 906: const char *host = options.host_key_alias ? options.host_key_alias :
907: authctxt->host;
1.99 markus 908:
909: debug2("input_userauth_passwd_changereq");
910:
911: if (authctxt == NULL)
912: fatal("input_userauth_passwd_changereq: "
913: "no authentication context");
914:
915: info = packet_get_string(NULL);
916: lang = packet_get_string(NULL);
917: if (strlen(info) > 0)
1.116 itojun 918: logit("%s", info);
1.197 djm 919: free(info);
920: free(lang);
1.99 markus 921: packet_start(SSH2_MSG_USERAUTH_REQUEST);
922: packet_put_cstring(authctxt->server_user);
923: packet_put_cstring(authctxt->service);
924: packet_put_cstring(authctxt->method->name);
925: packet_put_char(1); /* additional info */
1.104 deraadt 926: snprintf(prompt, sizeof(prompt),
1.99 markus 927: "Enter %.30s@%.128s's old password: ",
1.175 dtucker 928: authctxt->server_user, host);
1.99 markus 929: password = read_passphrase(prompt, 0);
930: packet_put_cstring(password);
1.204 djm 931: explicit_bzero(password, strlen(password));
1.197 djm 932: free(password);
1.99 markus 933: password = NULL;
934: while (password == NULL) {
1.104 deraadt 935: snprintf(prompt, sizeof(prompt),
1.99 markus 936: "Enter %.30s@%.128s's new password: ",
1.175 dtucker 937: authctxt->server_user, host);
1.99 markus 938: password = read_passphrase(prompt, RP_ALLOW_EOF);
939: if (password == NULL) {
940: /* bail out */
1.218 markus 941: return 0;
1.99 markus 942: }
1.104 deraadt 943: snprintf(prompt, sizeof(prompt),
1.99 markus 944: "Retype %.30s@%.128s's new password: ",
1.175 dtucker 945: authctxt->server_user, host);
1.99 markus 946: retype = read_passphrase(prompt, 0);
947: if (strcmp(password, retype) != 0) {
1.204 djm 948: explicit_bzero(password, strlen(password));
1.197 djm 949: free(password);
1.116 itojun 950: logit("Mismatch; try again, EOF to quit.");
1.99 markus 951: password = NULL;
952: }
1.204 djm 953: explicit_bzero(retype, strlen(retype));
1.197 djm 954: free(retype);
1.99 markus 955: }
956: packet_put_cstring(password);
1.204 djm 957: explicit_bzero(password, strlen(password));
1.197 djm 958: free(password);
1.99 markus 959: packet_add_padding(64);
960: packet_send();
1.104 deraadt 961:
962: dispatch_set(SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
1.99 markus 963: &input_userauth_passwd_changereq);
1.218 markus 964: return 0;
1.117 markus 965: }
966:
967: static int
1.214 djm 968: identity_sign(struct identity *id, u_char **sigp, size_t *lenp,
969: const u_char *data, size_t datalen, u_int compat)
1.117 markus 970: {
971: Key *prv;
972: int ret;
1.99 markus 973:
1.117 markus 974: /* the agent supports this key */
1.214 djm 975: if (id->agent_fd)
976: return ssh_agent_sign(id->agent_fd, id->key, sigp, lenp,
977: data, datalen, compat);
978:
1.117 markus 979: /*
980: * we have already loaded the private key or
981: * the private key is stored in external hardware
982: */
1.209 djm 983: if (id->isprivate || (id->key->flags & SSHKEY_FLAG_EXT))
1.214 djm 984: return (sshkey_sign(id->key, sigp, lenp, data, datalen,
985: compat));
1.117 markus 986: /* load the private key from the file */
1.191 dtucker 987: if ((prv = load_identity_file(id->filename, id->userprovided)) == NULL)
1.214 djm 988: return (-1); /* XXX return decent error code */
989: ret = sshkey_sign(prv, sigp, lenp, data, datalen, compat);
990: sshkey_free(prv);
1.117 markus 991: return (ret);
1.51 markus 992: }
993:
1.76 itojun 994: static int
1.117 markus 995: sign_and_send_pubkey(Authctxt *authctxt, Identity *id)
1.1 markus 996: {
997: Buffer b;
1.32 markus 998: u_char *blob, *signature;
1.214 djm 999: u_int bloblen;
1000: size_t slen;
1.120 markus 1001: u_int skip = 0;
1.17 markus 1002: int ret = -1;
1.23 markus 1003: int have_sig = 1;
1.182 djm 1004: char *fp;
1.1 markus 1005:
1.212 djm 1006: fp = key_fingerprint(id->key, options.fingerprint_hash, SSH_FP_DEFAULT);
1.182 djm 1007: debug3("sign_and_send_pubkey: %s %s", key_type(id->key), fp);
1.197 djm 1008: free(fp);
1.51 markus 1009:
1.117 markus 1010: if (key_to_blob(id->key, &blob, &bloblen) == 0) {
1.28 markus 1011: /* we cannot handle this key */
1.30 markus 1012: debug3("sign_and_send_pubkey: cannot handle key");
1.28 markus 1013: return 0;
1014: }
1.1 markus 1015: /* data to be signed */
1016: buffer_init(&b);
1.26 markus 1017: if (datafellows & SSH_OLD_SESSIONID) {
1018: buffer_append(&b, session_id2, session_id2_len);
1.41 stevesk 1019: skip = session_id2_len;
1.26 markus 1020: } else {
1.14 markus 1021: buffer_put_string(&b, session_id2, session_id2_len);
1022: skip = buffer_len(&b);
1023: }
1.1 markus 1024: buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
1.20 markus 1025: buffer_put_cstring(&b, authctxt->server_user);
1.10 markus 1026: buffer_put_cstring(&b,
1.30 markus 1027: datafellows & SSH_BUG_PKSERVICE ?
1.10 markus 1028: "ssh-userauth" :
1.20 markus 1029: authctxt->service);
1.30 markus 1030: if (datafellows & SSH_BUG_PKAUTH) {
1031: buffer_put_char(&b, have_sig);
1032: } else {
1033: buffer_put_cstring(&b, authctxt->method->name);
1034: buffer_put_char(&b, have_sig);
1.117 markus 1035: buffer_put_cstring(&b, key_ssh_name(id->key));
1.30 markus 1036: }
1.1 markus 1037: buffer_put_string(&b, blob, bloblen);
1038:
1039: /* generate signature */
1.117 markus 1040: ret = identity_sign(id, &signature, &slen,
1.214 djm 1041: buffer_ptr(&b), buffer_len(&b), datafellows);
1042: if (ret != 0) {
1.197 djm 1043: free(blob);
1.17 markus 1044: buffer_free(&b);
1045: return 0;
1046: }
1.28 markus 1047: #ifdef DEBUG_PK
1.1 markus 1048: buffer_dump(&b);
1049: #endif
1.30 markus 1050: if (datafellows & SSH_BUG_PKSERVICE) {
1.10 markus 1051: buffer_clear(&b);
1052: buffer_append(&b, session_id2, session_id2_len);
1.51 markus 1053: skip = session_id2_len;
1.10 markus 1054: buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
1.20 markus 1055: buffer_put_cstring(&b, authctxt->server_user);
1056: buffer_put_cstring(&b, authctxt->service);
1.23 markus 1057: buffer_put_cstring(&b, authctxt->method->name);
1058: buffer_put_char(&b, have_sig);
1.30 markus 1059: if (!(datafellows & SSH_BUG_PKAUTH))
1.117 markus 1060: buffer_put_cstring(&b, key_ssh_name(id->key));
1.10 markus 1061: buffer_put_string(&b, blob, bloblen);
1062: }
1.197 djm 1063: free(blob);
1.51 markus 1064:
1.1 markus 1065: /* append signature */
1066: buffer_put_string(&b, signature, slen);
1.197 djm 1067: free(signature);
1.1 markus 1068:
1069: /* skip session id and packet type */
1.14 markus 1070: if (buffer_len(&b) < skip + 1)
1.20 markus 1071: fatal("userauth_pubkey: internal error");
1.14 markus 1072: buffer_consume(&b, skip + 1);
1.1 markus 1073:
1074: /* put remaining data from buffer into packet */
1075: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1076: packet_put_raw(buffer_ptr(&b), buffer_len(&b));
1077: buffer_free(&b);
1078: packet_send();
1.17 markus 1079:
1080: return 1;
1.16 markus 1081: }
1082:
1.76 itojun 1083: static int
1.117 markus 1084: send_pubkey_test(Authctxt *authctxt, Identity *id)
1.20 markus 1085: {
1.51 markus 1086: u_char *blob;
1.97 markus 1087: u_int bloblen, have_sig = 0;
1.20 markus 1088:
1.51 markus 1089: debug3("send_pubkey_test");
1.16 markus 1090:
1.117 markus 1091: if (key_to_blob(id->key, &blob, &bloblen) == 0) {
1.51 markus 1092: /* we cannot handle this key */
1093: debug3("send_pubkey_test: cannot handle key");
1.16 markus 1094: return 0;
1095: }
1.51 markus 1096: /* register callback for USERAUTH_PK_OK message */
1097: dispatch_set(SSH2_MSG_USERAUTH_PK_OK, &input_userauth_pk_ok);
1098:
1099: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1100: packet_put_cstring(authctxt->server_user);
1101: packet_put_cstring(authctxt->service);
1102: packet_put_cstring(authctxt->method->name);
1103: packet_put_char(have_sig);
1104: if (!(datafellows & SSH_BUG_PKAUTH))
1.117 markus 1105: packet_put_cstring(key_ssh_name(id->key));
1.51 markus 1106: packet_put_string(blob, bloblen);
1.197 djm 1107: free(blob);
1.51 markus 1108: packet_send();
1109: return 1;
1110: }
1111:
1.76 itojun 1112: static Key *
1.191 dtucker 1113: load_identity_file(char *filename, int userprovided)
1.51 markus 1114: {
1115: Key *private;
1116: char prompt[300], *passphrase;
1.215 djm 1117: int r, perm_ok = 0, quit = 0, i;
1.52 markus 1118: struct stat st;
1.16 markus 1119:
1.52 markus 1120: if (stat(filename, &st) < 0) {
1.191 dtucker 1121: (userprovided ? logit : debug3)("no such identity: %s: %s",
1122: filename, strerror(errno));
1.52 markus 1123: return NULL;
1124: }
1.214 djm 1125: snprintf(prompt, sizeof prompt,
1126: "Enter passphrase for key '%.100s': ", filename);
1127: for (i = 0; i <= options.number_of_password_prompts; i++) {
1128: if (i == 0)
1129: passphrase = "";
1130: else {
1.20 markus 1131: passphrase = read_passphrase(prompt, 0);
1.214 djm 1132: if (*passphrase == '\0') {
1.20 markus 1133: debug2("no passphrase given, try next key");
1.214 djm 1134: free(passphrase);
1135: break;
1136: }
1137: }
1138: switch ((r = sshkey_load_private_type(KEY_UNSPEC, filename,
1139: passphrase, &private, NULL, &perm_ok))) {
1140: case 0:
1141: break;
1142: case SSH_ERR_KEY_WRONG_PASSPHRASE:
1143: if (options.batch_mode) {
1144: quit = 1;
1145: break;
1146: }
1.215 djm 1147: if (i != 0)
1148: debug2("bad passphrase given, try again...");
1.214 djm 1149: break;
1150: case SSH_ERR_SYSTEM_ERROR:
1151: if (errno == ENOENT) {
1152: debug2("Load key \"%s\": %s",
1153: filename, ssh_err(r));
1.51 markus 1154: quit = 1;
1.214 djm 1155: break;
1.20 markus 1156: }
1.214 djm 1157: /* FALLTHROUGH */
1158: default:
1159: error("Load key \"%s\": %s", filename, ssh_err(r));
1160: quit = 1;
1161: break;
1162: }
1163: if (i > 0) {
1.204 djm 1164: explicit_bzero(passphrase, strlen(passphrase));
1.197 djm 1165: free(passphrase);
1.16 markus 1166: }
1.214 djm 1167: if (private != NULL || quit)
1168: break;
1.16 markus 1169: }
1.51 markus 1170: return private;
1171: }
1172:
1.117 markus 1173: /*
1174: * try keys in the following order:
1175: * 1. agent keys that are found in the config file
1176: * 2. other agent keys
1177: * 3. keys that are only listed in the config file
1178: */
1179: static void
1180: pubkey_prepare(Authctxt *authctxt)
1.51 markus 1181: {
1.214 djm 1182: struct identity *id, *id2, *tmp;
1183: struct idlist agent, files, *preferred;
1184: struct sshkey *key;
1185: int agent_fd, i, r, found;
1186: size_t j;
1187: struct ssh_identitylist *idlist;
1.51 markus 1188:
1.117 markus 1189: TAILQ_INIT(&agent); /* keys from the agent */
1190: TAILQ_INIT(&files); /* keys from the config file */
1191: preferred = &authctxt->keys;
1192: TAILQ_INIT(preferred); /* preferred order of keys */
1193:
1.190 djm 1194: /* list of keys stored in the filesystem and PKCS#11 */
1.117 markus 1195: for (i = 0; i < options.num_identity_files; i++) {
1196: key = options.identity_keys[i];
1197: if (key && key->type == KEY_RSA1)
1.180 djm 1198: continue;
1199: if (key && key->cert && key->cert->type != SSH2_CERT_TYPE_USER)
1.117 markus 1200: continue;
1201: options.identity_keys[i] = NULL;
1.150 djm 1202: id = xcalloc(1, sizeof(*id));
1.117 markus 1203: id->key = key;
1204: id->filename = xstrdup(options.identity_files[i]);
1.192 dtucker 1205: id->userprovided = options.identity_file_userprovided[i];
1.117 markus 1206: TAILQ_INSERT_TAIL(&files, id, next);
1.190 djm 1207: }
1208: /* Prefer PKCS11 keys that are explicitly listed */
1209: TAILQ_FOREACH_SAFE(id, &files, next, tmp) {
1.209 djm 1210: if (id->key == NULL || (id->key->flags & SSHKEY_FLAG_EXT) == 0)
1.190 djm 1211: continue;
1212: found = 0;
1213: TAILQ_FOREACH(id2, &files, next) {
1214: if (id2->key == NULL ||
1.209 djm 1215: (id2->key->flags & SSHKEY_FLAG_EXT) == 0)
1.190 djm 1216: continue;
1.214 djm 1217: if (sshkey_equal(id->key, id2->key)) {
1.190 djm 1218: TAILQ_REMOVE(&files, id, next);
1219: TAILQ_INSERT_TAIL(preferred, id, next);
1220: found = 1;
1221: break;
1222: }
1223: }
1224: /* If IdentitiesOnly set and key not found then don't use it */
1225: if (!found && options.identities_only) {
1226: TAILQ_REMOVE(&files, id, next);
1.203 tedu 1227: explicit_bzero(id, sizeof(*id));
1.190 djm 1228: free(id);
1229: }
1.117 markus 1230: }
1231: /* list of keys supported by the agent */
1.214 djm 1232: if ((r = ssh_get_authentication_socket(&agent_fd)) != 0) {
1233: if (r != SSH_ERR_AGENT_NOT_PRESENT)
1234: debug("%s: ssh_get_authentication_socket: %s",
1235: __func__, ssh_err(r));
1236: } else if ((r = ssh_fetch_identitylist(agent_fd, 2, &idlist)) != 0) {
1237: if (r != SSH_ERR_AGENT_NO_IDENTITIES)
1238: debug("%s: ssh_fetch_identitylist: %s",
1239: __func__, ssh_err(r));
1240: } else {
1241: for (j = 0; j < idlist->nkeys; j++) {
1.117 markus 1242: found = 0;
1243: TAILQ_FOREACH(id, &files, next) {
1.214 djm 1244: /*
1245: * agent keys from the config file are
1246: * preferred
1247: */
1248: if (sshkey_equal(idlist->keys[j], id->key)) {
1.117 markus 1249: TAILQ_REMOVE(&files, id, next);
1250: TAILQ_INSERT_TAIL(preferred, id, next);
1.214 djm 1251: id->agent_fd = agent_fd;
1.117 markus 1252: found = 1;
1253: break;
1254: }
1255: }
1.135 markus 1256: if (!found && !options.identities_only) {
1.150 djm 1257: id = xcalloc(1, sizeof(*id));
1.214 djm 1258: /* XXX "steals" key/comment from idlist */
1259: id->key = idlist->keys[j];
1260: id->filename = idlist->comments[j];
1261: idlist->keys[j] = NULL;
1262: idlist->comments[j] = NULL;
1263: id->agent_fd = agent_fd;
1.117 markus 1264: TAILQ_INSERT_TAIL(&agent, id, next);
1265: }
1266: }
1.214 djm 1267: ssh_free_identitylist(idlist);
1.117 markus 1268: /* append remaining agent keys */
1269: for (id = TAILQ_FIRST(&agent); id; id = TAILQ_FIRST(&agent)) {
1270: TAILQ_REMOVE(&agent, id, next);
1271: TAILQ_INSERT_TAIL(preferred, id, next);
1272: }
1.214 djm 1273: authctxt->agent_fd = agent_fd;
1.117 markus 1274: }
1275: /* append remaining keys from the config file */
1276: for (id = TAILQ_FIRST(&files); id; id = TAILQ_FIRST(&files)) {
1277: TAILQ_REMOVE(&files, id, next);
1278: TAILQ_INSERT_TAIL(preferred, id, next);
1279: }
1280: TAILQ_FOREACH(id, preferred, next) {
1.191 dtucker 1281: debug2("key: %s (%p),%s", id->filename, id->key,
1282: id->userprovided ? " explicit" : "");
1.117 markus 1283: }
1.17 markus 1284: }
1285:
1.117 markus 1286: static void
1287: pubkey_cleanup(Authctxt *authctxt)
1.51 markus 1288: {
1.117 markus 1289: Identity *id;
1.51 markus 1290:
1.214 djm 1291: if (authctxt->agent_fd != -1)
1292: ssh_close_authentication_socket(authctxt->agent_fd);
1.117 markus 1293: for (id = TAILQ_FIRST(&authctxt->keys); id;
1294: id = TAILQ_FIRST(&authctxt->keys)) {
1295: TAILQ_REMOVE(&authctxt->keys, id, next);
1296: if (id->key)
1.214 djm 1297: sshkey_free(id->key);
1.197 djm 1298: free(id->filename);
1299: free(id);
1.117 markus 1300: }
1.1 markus 1301: }
1302:
1.20 markus 1303: int
1304: userauth_pubkey(Authctxt *authctxt)
1305: {
1.117 markus 1306: Identity *id;
1.20 markus 1307: int sent = 0;
1308:
1.117 markus 1309: while ((id = TAILQ_FIRST(&authctxt->keys))) {
1310: if (id->tried++)
1311: return (0);
1.127 markus 1312: /* move key to the end of the queue */
1.117 markus 1313: TAILQ_REMOVE(&authctxt->keys, id, next);
1314: TAILQ_INSERT_TAIL(&authctxt->keys, id, next);
1315: /*
1316: * send a test message if we have the public key. for
1317: * encrypted keys we cannot do this and have to load the
1318: * private key instead
1319: */
1.200 djm 1320: if (id->key != NULL) {
1321: if (key_type_plain(id->key->type) == KEY_RSA &&
1322: (datafellows & SSH_BUG_RSASIGMD5) != 0) {
1323: debug("Skipped %s key %s for RSA/MD5 server",
1324: key_type(id->key), id->filename);
1325: } else if (id->key->type != KEY_RSA1) {
1326: debug("Offering %s public key: %s",
1327: key_type(id->key), id->filename);
1328: sent = send_pubkey_test(authctxt, id);
1329: }
1330: } else {
1.117 markus 1331: debug("Trying private key: %s", id->filename);
1.191 dtucker 1332: id->key = load_identity_file(id->filename,
1333: id->userprovided);
1.117 markus 1334: if (id->key != NULL) {
1335: id->isprivate = 1;
1.200 djm 1336: if (key_type_plain(id->key->type) == KEY_RSA &&
1337: (datafellows & SSH_BUG_RSASIGMD5) != 0) {
1338: debug("Skipped %s key %s for RSA/MD5 "
1339: "server", key_type(id->key),
1340: id->filename);
1341: } else {
1342: sent = sign_and_send_pubkey(
1343: authctxt, id);
1344: }
1.117 markus 1345: key_free(id->key);
1346: id->key = NULL;
1.51 markus 1347: }
1348: }
1.117 markus 1349: if (sent)
1350: return (sent);
1.28 markus 1351: }
1.117 markus 1352: return (0);
1.20 markus 1353: }
1354:
1.23 markus 1355: /*
1356: * Send userauth request message specifying keyboard-interactive method.
1357: */
1358: int
1359: userauth_kbdint(Authctxt *authctxt)
1360: {
1361: static int attempt = 0;
1362:
1363: if (attempt++ >= options.number_of_password_prompts)
1364: return 0;
1.82 markus 1365: /* disable if no SSH2_MSG_USERAUTH_INFO_REQUEST has been seen */
1366: if (attempt > 1 && !authctxt->info_req_seen) {
1367: debug3("userauth_kbdint: disable: no info_req_seen");
1368: dispatch_set(SSH2_MSG_USERAUTH_INFO_REQUEST, NULL);
1369: return 0;
1370: }
1.23 markus 1371:
1372: debug2("userauth_kbdint");
1373: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1374: packet_put_cstring(authctxt->server_user);
1375: packet_put_cstring(authctxt->service);
1376: packet_put_cstring(authctxt->method->name);
1377: packet_put_cstring(""); /* lang */
1378: packet_put_cstring(options.kbd_interactive_devices ?
1379: options.kbd_interactive_devices : "");
1380: packet_send();
1381:
1382: dispatch_set(SSH2_MSG_USERAUTH_INFO_REQUEST, &input_userauth_info_req);
1383: return 1;
1384: }
1385:
1386: /*
1.46 markus 1387: * parse INFO_REQUEST, prompt user and send INFO_RESPONSE
1.23 markus 1388: */
1.218 markus 1389: int
1.92 markus 1390: input_userauth_info_req(int type, u_int32_t seq, void *ctxt)
1.23 markus 1391: {
1392: Authctxt *authctxt = ctxt;
1.46 markus 1393: char *name, *inst, *lang, *prompt, *response;
1.32 markus 1394: u_int num_prompts, i;
1.23 markus 1395: int echo = 0;
1396:
1397: debug2("input_userauth_info_req");
1398:
1399: if (authctxt == NULL)
1400: fatal("input_userauth_info_req: no authentication context");
1.82 markus 1401:
1402: authctxt->info_req_seen = 1;
1.23 markus 1403:
1404: name = packet_get_string(NULL);
1405: inst = packet_get_string(NULL);
1406: lang = packet_get_string(NULL);
1407: if (strlen(name) > 0)
1.116 itojun 1408: logit("%s", name);
1.23 markus 1409: if (strlen(inst) > 0)
1.116 itojun 1410: logit("%s", inst);
1.197 djm 1411: free(name);
1412: free(inst);
1413: free(lang);
1.23 markus 1414:
1415: num_prompts = packet_get_int();
1416: /*
1417: * Begin to build info response packet based on prompts requested.
1418: * We commit to providing the correct number of responses, so if
1419: * further on we run into a problem that prevents this, we have to
1420: * be sure and clean this up and send a correct error response.
1421: */
1422: packet_start(SSH2_MSG_USERAUTH_INFO_RESPONSE);
1423: packet_put_int(num_prompts);
1424:
1.73 markus 1425: debug2("input_userauth_info_req: num_prompts %d", num_prompts);
1.23 markus 1426: for (i = 0; i < num_prompts; i++) {
1427: prompt = packet_get_string(NULL);
1428: echo = packet_get_char();
1429:
1.77 markus 1430: response = read_passphrase(prompt, echo ? RP_ECHO : 0);
1.23 markus 1431:
1.49 markus 1432: packet_put_cstring(response);
1.204 djm 1433: explicit_bzero(response, strlen(response));
1.197 djm 1434: free(response);
1435: free(prompt);
1.23 markus 1436: }
1.90 markus 1437: packet_check_eom(); /* done with parsing incoming message. */
1.23 markus 1438:
1.85 markus 1439: packet_add_padding(64);
1.23 markus 1440: packet_send();
1.218 markus 1441: return 0;
1.68 markus 1442: }
1443:
1.100 markus 1444: static int
1.105 deraadt 1445: ssh_keysign(Key *key, u_char **sigp, u_int *lenp,
1.100 markus 1446: u_char *data, u_int datalen)
1447: {
1448: Buffer b;
1.101 markus 1449: struct stat st;
1.100 markus 1450: pid_t pid;
1.103 markus 1451: int to[2], from[2], status, version = 2;
1.100 markus 1452:
1.109 markus 1453: debug2("ssh_keysign called");
1.100 markus 1454:
1.101 markus 1455: if (stat(_PATH_SSH_KEY_SIGN, &st) < 0) {
1.179 dtucker 1456: error("ssh_keysign: not installed: %s", strerror(errno));
1.101 markus 1457: return -1;
1458: }
1.100 markus 1459: if (fflush(stdout) != 0)
1460: error("ssh_keysign: fflush: %s", strerror(errno));
1461: if (pipe(to) < 0) {
1462: error("ssh_keysign: pipe: %s", strerror(errno));
1463: return -1;
1464: }
1465: if (pipe(from) < 0) {
1466: error("ssh_keysign: pipe: %s", strerror(errno));
1467: return -1;
1468: }
1469: if ((pid = fork()) < 0) {
1470: error("ssh_keysign: fork: %s", strerror(errno));
1471: return -1;
1472: }
1473: if (pid == 0) {
1.174 dtucker 1474: /* keep the socket on exec */
1475: fcntl(packet_get_connection_in(), F_SETFD, 0);
1.155 markus 1476: permanently_drop_suid(getuid());
1.100 markus 1477: close(from[0]);
1478: if (dup2(from[1], STDOUT_FILENO) < 0)
1479: fatal("ssh_keysign: dup2: %s", strerror(errno));
1480: close(to[1]);
1481: if (dup2(to[0], STDIN_FILENO) < 0)
1482: fatal("ssh_keysign: dup2: %s", strerror(errno));
1.103 markus 1483: close(from[1]);
1484: close(to[0]);
1.102 markus 1485: execl(_PATH_SSH_KEY_SIGN, _PATH_SSH_KEY_SIGN, (char *) 0);
1.100 markus 1486: fatal("ssh_keysign: exec(%s): %s", _PATH_SSH_KEY_SIGN,
1487: strerror(errno));
1488: }
1489: close(from[1]);
1490: close(to[0]);
1491:
1492: buffer_init(&b);
1.103 markus 1493: buffer_put_int(&b, packet_get_connection_in()); /* send # of socket */
1.100 markus 1494: buffer_put_string(&b, data, datalen);
1.131 djm 1495: if (ssh_msg_send(to[1], version, &b) == -1)
1496: fatal("ssh_keysign: couldn't send request");
1.100 markus 1497:
1.110 djm 1498: if (ssh_msg_recv(from[0], &b) < 0) {
1.101 markus 1499: error("ssh_keysign: no reply");
1.134 markus 1500: buffer_free(&b);
1.100 markus 1501: return -1;
1502: }
1.101 markus 1503: close(from[0]);
1504: close(to[1]);
1505:
1.103 markus 1506: while (waitpid(pid, &status, 0) < 0)
1507: if (errno != EINTR)
1508: break;
1.101 markus 1509:
1.100 markus 1510: if (buffer_get_char(&b) != version) {
1.101 markus 1511: error("ssh_keysign: bad version");
1.134 markus 1512: buffer_free(&b);
1.100 markus 1513: return -1;
1514: }
1515: *sigp = buffer_get_string(&b, lenp);
1.134 markus 1516: buffer_free(&b);
1.100 markus 1517:
1518: return 0;
1519: }
1520:
1.68 markus 1521: int
1522: userauth_hostbased(Authctxt *authctxt)
1523: {
1524: Key *private = NULL;
1.100 markus 1525: Sensitive *sensitive = authctxt->sensitive;
1.68 markus 1526: Buffer b;
1527: u_char *signature, *blob;
1.179 dtucker 1528: char *chost, *pkalg, *p;
1.72 markus 1529: const char *service;
1.68 markus 1530: u_int blen, slen;
1.176 dtucker 1531: int ok, i, found = 0;
1.213 djm 1532:
1533: /* XXX provide some way to allow user to specify key types attempted */
1.68 markus 1534:
1535: /* check for a useful key */
1.100 markus 1536: for (i = 0; i < sensitive->nkeys; i++) {
1537: private = sensitive->keys[i];
1.68 markus 1538: if (private && private->type != KEY_RSA1) {
1539: found = 1;
1540: /* we take and free the key */
1.100 markus 1541: sensitive->keys[i] = NULL;
1.68 markus 1542: break;
1543: }
1544: }
1545: if (!found) {
1.109 markus 1546: debug("No more client hostkeys for hostbased authentication.");
1.68 markus 1547: return 0;
1548: }
1.211 djm 1549:
1550: debug("%s: trying hostkey type %s", __func__, key_type(private));
1551:
1.68 markus 1552: if (key_to_blob(private, &blob, &blen) == 0) {
1553: key_free(private);
1554: return 0;
1555: }
1.211 djm 1556:
1.84 markus 1557: /* figure out a name for the client host */
1.179 dtucker 1558: p = get_local_name(packet_get_connection_in());
1.84 markus 1559: if (p == NULL) {
1560: error("userauth_hostbased: cannot get local ipaddr/name");
1561: key_free(private);
1.197 djm 1562: free(blob);
1.84 markus 1563: return 0;
1564: }
1.150 djm 1565: xasprintf(&chost, "%s.", p);
1.84 markus 1566: debug2("userauth_hostbased: chost %s", chost);
1.197 djm 1567: free(p);
1.84 markus 1568:
1.72 markus 1569: service = datafellows & SSH_BUG_HBSERVICE ? "ssh-userauth" :
1570: authctxt->service;
1.68 markus 1571: pkalg = xstrdup(key_ssh_name(private));
1572: buffer_init(&b);
1573: /* construct data */
1.72 markus 1574: buffer_put_string(&b, session_id2, session_id2_len);
1.68 markus 1575: buffer_put_char(&b, SSH2_MSG_USERAUTH_REQUEST);
1576: buffer_put_cstring(&b, authctxt->server_user);
1.72 markus 1577: buffer_put_cstring(&b, service);
1.68 markus 1578: buffer_put_cstring(&b, authctxt->method->name);
1579: buffer_put_cstring(&b, pkalg);
1580: buffer_put_string(&b, blob, blen);
1581: buffer_put_cstring(&b, chost);
1582: buffer_put_cstring(&b, authctxt->local_user);
1583: #ifdef DEBUG_PK
1584: buffer_dump(&b);
1585: #endif
1.100 markus 1586: if (sensitive->external_keysign)
1587: ok = ssh_keysign(private, &signature, &slen,
1588: buffer_ptr(&b), buffer_len(&b));
1589: else
1590: ok = key_sign(private, &signature, &slen,
1591: buffer_ptr(&b), buffer_len(&b));
1.68 markus 1592: key_free(private);
1593: buffer_free(&b);
1594: if (ok != 0) {
1595: error("key_sign failed");
1.197 djm 1596: free(chost);
1597: free(pkalg);
1598: free(blob);
1.68 markus 1599: return 0;
1600: }
1601: packet_start(SSH2_MSG_USERAUTH_REQUEST);
1602: packet_put_cstring(authctxt->server_user);
1603: packet_put_cstring(authctxt->service);
1604: packet_put_cstring(authctxt->method->name);
1605: packet_put_cstring(pkalg);
1606: packet_put_string(blob, blen);
1607: packet_put_cstring(chost);
1608: packet_put_cstring(authctxt->local_user);
1609: packet_put_string(signature, slen);
1.204 djm 1610: explicit_bzero(signature, slen);
1.197 djm 1611: free(signature);
1612: free(chost);
1613: free(pkalg);
1614: free(blob);
1.68 markus 1615:
1616: packet_send();
1617: return 1;
1.23 markus 1618: }
1.170 djm 1619:
1.20 markus 1620: /* find auth method */
1621:
1622: /*
1623: * given auth method name, if configurable options permit this method fill
1624: * in auth_ident field and return true, otherwise return false.
1625: */
1.76 itojun 1626: static int
1.20 markus 1627: authmethod_is_enabled(Authmethod *method)
1628: {
1629: if (method == NULL)
1630: return 0;
1631: /* return false if options indicate this method is disabled */
1632: if (method->enabled == NULL || *method->enabled == 0)
1633: return 0;
1634: /* return false if batch mode is enabled but method needs interactive mode */
1635: if (method->batch_flag != NULL && *method->batch_flag != 0)
1636: return 0;
1637: return 1;
1638: }
1639:
1.76 itojun 1640: static Authmethod *
1.20 markus 1641: authmethod_lookup(const char *name)
1.1 markus 1642: {
1.20 markus 1643: Authmethod *method = NULL;
1644: if (name != NULL)
1645: for (method = authmethods; method->name != NULL; method++)
1646: if (strcmp(name, method->name) == 0)
1647: return method;
1648: debug2("Unrecognized authentication method name: %s", name ? name : "NULL");
1649: return NULL;
1650: }
1.1 markus 1651:
1.53 markus 1652: /* XXX internal state */
1653: static Authmethod *current = NULL;
1654: static char *supported = NULL;
1655: static char *preferred = NULL;
1.105 deraadt 1656:
1.20 markus 1657: /*
1658: * Given the authentication method list sent by the server, return the
1659: * next method we should try. If the server initially sends a nil list,
1.67 markus 1660: * use a built-in default list.
1.41 stevesk 1661: */
1.76 itojun 1662: static Authmethod *
1.20 markus 1663: authmethod_get(char *authlist)
1664: {
1.53 markus 1665: char *name = NULL;
1.97 markus 1666: u_int next;
1.41 stevesk 1667:
1.20 markus 1668: /* Use a suitable default if we're passed a nil list. */
1669: if (authlist == NULL || strlen(authlist) == 0)
1.53 markus 1670: authlist = options.preferred_authentications;
1.20 markus 1671:
1.53 markus 1672: if (supported == NULL || strcmp(authlist, supported) != 0) {
1673: debug3("start over, passed a different list %s", authlist);
1.197 djm 1674: free(supported);
1.53 markus 1675: supported = xstrdup(authlist);
1676: preferred = options.preferred_authentications;
1677: debug3("preferred %s", preferred);
1678: current = NULL;
1679: } else if (current != NULL && authmethod_is_enabled(current))
1680: return current;
1.20 markus 1681:
1.53 markus 1682: for (;;) {
1683: if ((name = match_list(preferred, supported, &next)) == NULL) {
1.109 markus 1684: debug("No more authentication methods to try.");
1.53 markus 1685: current = NULL;
1686: return NULL;
1687: }
1688: preferred += next;
1.23 markus 1689: debug3("authmethod_lookup %s", name);
1.53 markus 1690: debug3("remaining preferred: %s", preferred);
1691: if ((current = authmethod_lookup(name)) != NULL &&
1692: authmethod_is_enabled(current)) {
1.23 markus 1693: debug3("authmethod_is_enabled %s", name);
1.109 markus 1694: debug("Next authentication method: %s", name);
1.197 djm 1695: free(name);
1.53 markus 1696: return current;
1.23 markus 1697: }
1.198 dtucker 1698: free(name);
1.1 markus 1699: }
1.53 markus 1700: }
1.1 markus 1701:
1.79 stevesk 1702: static char *
1.53 markus 1703: authmethods_get(void)
1704: {
1705: Authmethod *method = NULL;
1.93 markus 1706: Buffer b;
1707: char *list;
1.27 provos 1708:
1.93 markus 1709: buffer_init(&b);
1.53 markus 1710: for (method = authmethods; method->name != NULL; method++) {
1711: if (authmethod_is_enabled(method)) {
1.93 markus 1712: if (buffer_len(&b) > 0)
1713: buffer_append(&b, ",", 1);
1714: buffer_append(&b, method->name, strlen(method->name));
1.53 markus 1715: }
1716: }
1.93 markus 1717: buffer_append(&b, "\0", 1);
1718: list = xstrdup(buffer_ptr(&b));
1719: buffer_free(&b);
1720: return list;
1.1 markus 1721: }
1.170 djm 1722:
![[BACK]](/icons/back.gif){kind=icon}
Return to sshconnect2.c CVS log ![[TXT]](/icons/text.gif){kind=icon}
![[DIR]](/icons/dir.gif){kind=icon}
Up to [local] / src / usr.bin / ssh