Annotation of src/usr.bin/ssh/sshconnect2.c, Revision 1.326
1.326 ! djm 1: /* $OpenBSD: sshconnect2.c,v 1.325 2020/08/27 01:06:18 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>
1.313 deraadt 38: #include <stdarg.h>
1.160 deraadt 39: #include <signal.h>
40: #include <pwd.h>
1.157 stevesk 41: #include <unistd.h>
1.166 djm 42: #include <vis.h>
1.1 markus 43:
1.160 deraadt 44: #include "xmalloc.h"
1.1 markus 45: #include "ssh.h"
1.37 markus 46: #include "ssh2.h"
1.278 markus 47: #include "sshbuf.h"
1.1 markus 48: #include "packet.h"
49: #include "compat.h"
1.37 markus 50: #include "cipher.h"
1.278 markus 51: #include "sshkey.h"
1.1 markus 52: #include "kex.h"
53: #include "myproposal.h"
54: #include "sshconnect.h"
55: #include "authfile.h"
1.57 provos 56: #include "dh.h"
1.17 markus 57: #include "authfd.h"
1.37 markus 58: #include "log.h"
1.210 millert 59: #include "misc.h"
1.37 markus 60: #include "readconf.h"
1.53 markus 61: #include "match.h"
1.61 markus 62: #include "dispatch.h"
1.68 markus 63: #include "canohost.h"
1.100 markus 64: #include "msg.h"
65: #include "pathnames.h"
1.154 markus 66: #include "uidswap.h"
1.186 djm 67: #include "hostfile.h"
1.214 djm 68: #include "ssherr.h"
1.246 djm 69: #include "utf8.h"
1.309 djm 70: #include "ssh-sk.h"
1.312 djm 71: #include "sk-api.h"
1.22 provos 72:
1.121 markus 73: #ifdef GSSAPI
74: #include "ssh-gss.h"
75: #endif
1.293 djm 76:
1.1 markus 77: /* import */
78: extern char *client_version_string;
79: extern char *server_version_string;
80: extern Options options;
81:
82: /*
83: * SSH2 key exchange
84: */
85:
1.32 markus 86: u_char *session_id2 = NULL;
1.120 markus 87: u_int session_id2_len = 0;
1.1 markus 88:
1.61 markus 89: char *xxx_host;
90: struct sockaddr *xxx_hostaddr;
91:
1.76 itojun 92: static int
1.259 markus 93: verify_host_key_callback(struct sshkey *hostkey, struct ssh *ssh)
1.61 markus 94: {
1.75 markus 95: if (verify_host_key(xxx_host, xxx_hostaddr, hostkey) == -1)
1.83 markus 96: fatal("Host key verification failed.");
1.61 markus 97: return 0;
98: }
99:
1.326 ! djm 100: /* Returns the first item from a comma-separated algorithm list */
! 101: static char *
! 102: first_alg(const char *algs)
! 103: {
! 104: char *ret, *cp;
! 105:
! 106: ret = xstrdup(algs);
! 107: if ((cp = strchr(ret, ',')) != NULL)
! 108: *cp = '\0';
! 109: return ret;
! 110: }
! 111:
1.186 djm 112: static char *
113: order_hostkeyalgs(char *host, struct sockaddr *hostaddr, u_short port)
114: {
1.326 ! djm 115: char *oavail = NULL, *avail = NULL, *first = NULL, *last = NULL;
! 116: char *alg = NULL, *hostname = NULL, *ret = NULL, *best = NULL;
1.186 djm 117: size_t maxlen;
1.326 ! djm 118: struct hostkeys *hostkeys = NULL;
1.186 djm 119: int ktype;
1.188 djm 120: u_int i;
1.186 djm 121:
122: /* Find all hostkeys for this hostname */
123: get_hostfile_hostname_ipaddr(host, hostaddr, port, &hostname, NULL);
124: hostkeys = init_hostkeys();
1.188 djm 125: for (i = 0; i < options.num_user_hostfiles; i++)
126: load_hostkeys(hostkeys, hostname, options.user_hostfiles[i]);
127: for (i = 0; i < options.num_system_hostfiles; i++)
128: load_hostkeys(hostkeys, hostname, options.system_hostfiles[i]);
1.186 djm 129:
1.326 ! djm 130: /*
! 131: * If a plain public key exists that matches the type of the best
! 132: * preference HostkeyAlgorithms, then use the whole list as is.
! 133: * Note that we ignore whether the best preference algorithm is a
! 134: * certificate type, as sshconnect.c will downgrade certs to
! 135: * plain keys if necessary.
! 136: */
! 137: best = first_alg(options.hostkeyalgorithms);
! 138: if (lookup_key_in_hostkeys_by_type(hostkeys,
! 139: sshkey_type_plain(sshkey_type_from_name(best)), NULL)) {
! 140: debug3("%s: have matching best-preference key type %s, "
! 141: "using HostkeyAlgorithms verbatim", __func__, best);
! 142: ret = xstrdup(options.hostkeyalgorithms);
! 143: goto out;
! 144: }
! 145:
! 146: /*
! 147: * Otherwise, prefer the host key algorithms that match known keys
! 148: * while keeping the ordering of HostkeyAlgorithms as much as possible.
! 149: */
1.320 djm 150: oavail = avail = xstrdup(options.hostkeyalgorithms);
1.186 djm 151: maxlen = strlen(avail) + 1;
152: first = xmalloc(maxlen);
153: last = xmalloc(maxlen);
154: *first = *last = '\0';
155:
156: #define ALG_APPEND(to, from) \
157: do { \
158: if (*to != '\0') \
159: strlcat(to, ",", maxlen); \
160: strlcat(to, from, maxlen); \
161: } while (0)
162:
163: while ((alg = strsep(&avail, ",")) && *alg != '\0') {
1.214 djm 164: if ((ktype = sshkey_type_from_name(alg)) == KEY_UNSPEC)
1.186 djm 165: fatal("%s: unknown alg %s", __func__, alg);
1.322 djm 166: /*
167: * If we have a @cert-authority marker in known_hosts then
168: * prefer all certificate algorithms.
169: */
170: if (sshkey_type_is_cert(ktype) &&
171: lookup_marker_in_hostkeys(hostkeys, MRK_CA)) {
172: ALG_APPEND(first, alg);
173: continue;
174: }
175: /* If the key appears in known_hosts then prefer it */
1.186 djm 176: if (lookup_key_in_hostkeys_by_type(hostkeys,
1.322 djm 177: sshkey_type_plain(ktype), NULL)) {
1.186 djm 178: ALG_APPEND(first, alg);
1.322 djm 179: continue;
180: }
181: /* Otherwise, put it last */
182: ALG_APPEND(last, alg);
1.186 djm 183: }
184: #undef ALG_APPEND
1.216 djm 185: xasprintf(&ret, "%s%s%s", first,
186: (*first == '\0' || *last == '\0') ? "" : ",", last);
1.186 djm 187: if (*first != '\0')
188: debug3("%s: prefer hostkeyalgs: %s", __func__, first);
189:
1.326 ! djm 190: out:
! 191: free(best);
1.197 djm 192: free(first);
193: free(last);
194: free(hostname);
195: free(oavail);
1.186 djm 196: free_hostkeys(hostkeys);
197:
198: return ret;
199: }
200:
1.1 markus 201: void
1.291 djm 202: ssh_kex2(struct ssh *ssh, char *host, struct sockaddr *hostaddr, u_short port)
1.22 provos 203: {
1.205 markus 204: char *myproposal[PROPOSAL_MAX] = { KEX_CLIENT };
1.275 djm 205: char *s, *all_key;
1.320 djm 206: int r, use_known_hosts_order = 0;
1.61 markus 207:
208: xxx_host = host;
209: xxx_hostaddr = hostaddr;
1.22 provos 210:
1.320 djm 211: /*
212: * If the user has not specified HostkeyAlgorithms, or has only
213: * appended or removed algorithms from that list then prefer algorithms
214: * that are in the list that are supported by known_hosts keys.
215: */
216: if (options.hostkeyalgorithms == NULL ||
217: options.hostkeyalgorithms[0] == '-' ||
218: options.hostkeyalgorithms[0] == '+')
219: use_known_hosts_order = 1;
220:
221: /* Expand or fill in HostkeyAlgorithms */
222: all_key = sshkey_alg_list(0, 0, 1, ',');
223: if (kex_assemble_names(&options.hostkeyalgorithms,
224: kex_default_pk_alg(), all_key) != 0)
225: fatal("%s: kex_assemble_namelist", __func__);
226: free(all_key);
227:
1.231 markus 228: if ((s = kex_names_cat(options.kex_algorithms, "ext-info-c")) == NULL)
229: fatal("%s: kex_names_cat", __func__);
1.284 djm 230: myproposal[PROPOSAL_KEX_ALGS] = compat_kex_proposal(s);
1.60 stevesk 231: myproposal[PROPOSAL_ENC_ALGS_CTOS] =
1.284 djm 232: compat_cipher_proposal(options.ciphers);
1.60 stevesk 233: myproposal[PROPOSAL_ENC_ALGS_STOC] =
1.284 djm 234: compat_cipher_proposal(options.ciphers);
1.245 dtucker 235: myproposal[PROPOSAL_COMP_ALGS_CTOS] =
1.318 dtucker 236: myproposal[PROPOSAL_COMP_ALGS_STOC] =
237: (char *)compression_alg_list(options.compression);
1.226 djm 238: myproposal[PROPOSAL_MAC_ALGS_CTOS] =
239: myproposal[PROPOSAL_MAC_ALGS_STOC] = options.macs;
1.320 djm 240: if (use_known_hosts_order) {
241: /* Query known_hosts and prefer algorithms that appear there */
1.88 deraadt 242: myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] =
1.320 djm 243: compat_pkalg_proposal(
244: order_hostkeyalgs(host, hostaddr, port));
1.226 djm 245: } else {
1.320 djm 246: /* Use specified HostkeyAlgorithms exactly */
1.186 djm 247: myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] =
1.320 djm 248: compat_pkalg_proposal(options.hostkeyalgorithms);
1.186 djm 249: }
1.115 markus 250:
1.196 dtucker 251: if (options.rekey_limit || options.rekey_interval)
1.294 djm 252: ssh_packet_set_rekey_limits(ssh, options.rekey_limit,
1.254 dtucker 253: options.rekey_interval);
1.22 provos 254:
1.65 markus 255: /* start key exchange */
1.291 djm 256: if ((r = kex_setup(ssh, myproposal)) != 0)
1.221 markus 257: fatal("kex_setup: %s", ssh_err(r));
1.207 markus 258: #ifdef WITH_OPENSSL
1.301 djm 259: ssh->kex->kex[KEX_DH_GRP1_SHA1] = kex_gen_client;
260: ssh->kex->kex[KEX_DH_GRP14_SHA1] = kex_gen_client;
261: ssh->kex->kex[KEX_DH_GRP14_SHA256] = kex_gen_client;
262: ssh->kex->kex[KEX_DH_GRP16_SHA512] = kex_gen_client;
263: ssh->kex->kex[KEX_DH_GRP18_SHA512] = kex_gen_client;
1.291 djm 264: ssh->kex->kex[KEX_DH_GEX_SHA1] = kexgex_client;
265: ssh->kex->kex[KEX_DH_GEX_SHA256] = kexgex_client;
1.301 djm 266: ssh->kex->kex[KEX_ECDH_SHA2] = kex_gen_client;
1.207 markus 267: #endif
1.301 djm 268: ssh->kex->kex[KEX_C25519_SHA256] = kex_gen_client;
269: ssh->kex->kex[KEX_KEM_SNTRUP4591761X25519_SHA512] = kex_gen_client;
1.291 djm 270: ssh->kex->verify_host_key=&verify_host_key_callback;
1.22 provos 271:
1.291 djm 272: ssh_dispatch_run_fatal(ssh, DISPATCH_BLOCK, &ssh->kex->done);
1.173 andreas 273:
1.231 markus 274: /* remove ext-info from the KEX proposals for rekeying */
275: myproposal[PROPOSAL_KEX_ALGS] =
1.284 djm 276: compat_kex_proposal(options.kex_algorithms);
1.291 djm 277: if ((r = kex_prop2buf(ssh->kex->my, myproposal)) != 0)
1.231 markus 278: fatal("kex_prop2buf: %s", ssh_err(r));
1.62 markus 279:
1.291 djm 280: session_id2 = ssh->kex->session_id;
281: session_id2_len = ssh->kex->session_id_len;
1.22 provos 282:
283: #ifdef DEBUG_KEXDH
284: /* send 1st encrypted/maced/compressed message */
1.278 markus 285: if ((r = sshpkt_start(ssh, SSH2_MSG_IGNORE)) != 0 ||
286: (r = sshpkt_put_cstring(ssh, "markus")) != 0 ||
1.280 markus 287: (r = sshpkt_send(ssh)) != 0 ||
288: (r = ssh_packet_write_wait(ssh)) != 0)
1.278 markus 289: fatal("%s: %s", __func__, ssh_err(r));
1.22 provos 290: #endif
1.1 markus 291: }
1.11 markus 292:
1.1 markus 293: /*
294: * Authenticate user
295: */
1.20 markus 296:
1.214 djm 297: typedef struct cauthctxt Authctxt;
298: typedef struct cauthmethod Authmethod;
1.117 markus 299: typedef struct identity Identity;
300: typedef struct idlist Idlist;
1.20 markus 301:
1.117 markus 302: struct identity {
303: TAILQ_ENTRY(identity) next;
1.214 djm 304: int agent_fd; /* >=0 if agent supports key */
305: struct sshkey *key; /* public/private key */
1.117 markus 306: char *filename; /* comment for agent-only keys */
307: int tried;
308: int isprivate; /* key points to the private key */
1.191 dtucker 309: int userprovided;
1.117 markus 310: };
311: TAILQ_HEAD(idlist, identity);
1.20 markus 312:
1.214 djm 313: struct cauthctxt {
1.20 markus 314: const char *server_user;
1.68 markus 315: const char *local_user;
1.20 markus 316: const char *host;
317: const char *service;
1.214 djm 318: struct cauthmethod *method;
1.183 djm 319: sig_atomic_t success;
1.51 markus 320: char *authlist;
1.302 djm 321: #ifdef GSSAPI
322: /* gssapi */
323: gss_OID_set gss_supported_mechs;
324: u_int mech_tried;
325: #endif
1.68 markus 326: /* pubkey */
1.214 djm 327: struct idlist keys;
328: int agent_fd;
1.68 markus 329: /* hostbased */
1.100 markus 330: Sensitive *sensitive;
1.223 djm 331: char *oktypes, *ktypes;
332: const char *active_ktype;
1.82 markus 333: /* kbd-interactive */
334: int info_req_seen;
1.292 djm 335: int attempt_kbdint;
336: /* password */
337: int attempt_passwd;
1.121 markus 338: /* generic */
339: void *methoddata;
1.20 markus 340: };
1.214 djm 341:
342: struct cauthmethod {
1.20 markus 343: char *name; /* string to compare against server's list */
1.295 djm 344: int (*userauth)(struct ssh *ssh);
345: void (*cleanup)(struct ssh *ssh);
1.20 markus 346: int *enabled; /* flag in option struct that enables method */
347: int *batch_flag; /* flag in option struct that disables method */
348: };
349:
1.302 djm 350: static int input_userauth_service_accept(int, u_int32_t, struct ssh *);
351: static int input_userauth_ext_info(int, u_int32_t, struct ssh *);
352: static int input_userauth_success(int, u_int32_t, struct ssh *);
353: static int input_userauth_failure(int, u_int32_t, struct ssh *);
354: static int input_userauth_banner(int, u_int32_t, struct ssh *);
355: static int input_userauth_error(int, u_int32_t, struct ssh *);
356: static int input_userauth_info_req(int, u_int32_t, struct ssh *);
357: static int input_userauth_pk_ok(int, u_int32_t, struct ssh *);
358: static int input_userauth_passwd_changereq(int, u_int32_t, struct ssh *);
359:
360: static int userauth_none(struct ssh *);
361: static int userauth_pubkey(struct ssh *);
362: static int userauth_passwd(struct ssh *);
363: static int userauth_kbdint(struct ssh *);
364: static int userauth_hostbased(struct ssh *);
1.20 markus 365:
1.121 markus 366: #ifdef GSSAPI
1.302 djm 367: static int userauth_gssapi(struct ssh *);
368: static void userauth_gssapi_cleanup(struct ssh *);
369: static int input_gssapi_response(int type, u_int32_t, struct ssh *);
370: static int input_gssapi_token(int type, u_int32_t, struct ssh *);
371: static int input_gssapi_error(int, u_int32_t, struct ssh *);
372: static int input_gssapi_errtok(int, u_int32_t, struct ssh *);
1.121 markus 373: #endif
374:
1.295 djm 375: void userauth(struct ssh *, char *);
1.51 markus 376:
1.303 djm 377: static void pubkey_cleanup(struct ssh *);
1.295 djm 378: static int sign_and_send_pubkey(struct ssh *ssh, Identity *);
1.117 markus 379: static void pubkey_prepare(Authctxt *);
1.251 djm 380: static void pubkey_reset(Authctxt *);
1.259 markus 381: static struct sshkey *load_identity_file(Identity *);
1.76 itojun 382:
383: static Authmethod *authmethod_get(char *authlist);
384: static Authmethod *authmethod_lookup(const char *name);
385: static char *authmethods_get(void);
1.20 markus 386:
387: Authmethod authmethods[] = {
1.121 markus 388: #ifdef GSSAPI
1.132 markus 389: {"gssapi-with-mic",
1.121 markus 390: userauth_gssapi,
1.302 djm 391: userauth_gssapi_cleanup,
1.121 markus 392: &options.gss_authentication,
393: NULL},
394: #endif
1.81 markus 395: {"hostbased",
396: userauth_hostbased,
1.170 djm 397: NULL,
1.81 markus 398: &options.hostbased_authentication,
399: NULL},
1.20 markus 400: {"publickey",
401: userauth_pubkey,
1.303 djm 402: NULL,
1.28 markus 403: &options.pubkey_authentication,
1.20 markus 404: NULL},
1.81 markus 405: {"keyboard-interactive",
406: userauth_kbdint,
1.170 djm 407: NULL,
1.81 markus 408: &options.kbd_interactive_authentication,
409: &options.batch_mode},
1.20 markus 410: {"password",
411: userauth_passwd,
1.170 djm 412: NULL,
1.20 markus 413: &options.password_authentication,
1.23 markus 414: &options.batch_mode},
415: {"none",
416: userauth_none,
417: NULL,
1.170 djm 418: NULL,
1.23 markus 419: NULL},
1.170 djm 420: {NULL, NULL, NULL, NULL, NULL}
1.20 markus 421: };
422:
423: void
1.291 djm 424: ssh_userauth2(struct ssh *ssh, const char *local_user,
425: const char *server_user, char *host, Sensitive *sensitive)
1.20 markus 426: {
427: Authctxt authctxt;
1.231 markus 428: int r;
1.39 markus 429:
1.73 markus 430: if (options.challenge_response_authentication)
1.39 markus 431: options.kbd_interactive_authentication = 1;
1.53 markus 432: if (options.preferred_authentications == NULL)
433: options.preferred_authentications = authmethods_get();
434:
1.20 markus 435: /* setup authentication context */
1.82 markus 436: memset(&authctxt, 0, sizeof(authctxt));
1.20 markus 437: authctxt.server_user = server_user;
1.68 markus 438: authctxt.local_user = local_user;
1.20 markus 439: authctxt.host = host;
440: authctxt.service = "ssh-connection"; /* service name */
441: authctxt.success = 0;
1.23 markus 442: authctxt.method = authmethod_lookup("none");
1.51 markus 443: authctxt.authlist = NULL;
1.121 markus 444: authctxt.methoddata = NULL;
1.100 markus 445: authctxt.sensitive = sensitive;
1.223 djm 446: authctxt.active_ktype = authctxt.oktypes = authctxt.ktypes = NULL;
1.82 markus 447: authctxt.info_req_seen = 0;
1.292 djm 448: authctxt.attempt_kbdint = 0;
449: authctxt.attempt_passwd = 0;
1.302 djm 450: #if GSSAPI
451: authctxt.gss_supported_mechs = NULL;
452: authctxt.mech_tried = 0;
453: #endif
1.215 djm 454: authctxt.agent_fd = -1;
1.289 djm 455: pubkey_prepare(&authctxt);
1.291 djm 456: if (authctxt.method == NULL) {
457: fatal("%s: internal error: cannot send userauth none request",
458: __func__);
459: }
1.20 markus 460:
1.231 markus 461: if ((r = sshpkt_start(ssh, SSH2_MSG_SERVICE_REQUEST)) != 0 ||
462: (r = sshpkt_put_cstring(ssh, "ssh-userauth")) != 0 ||
463: (r = sshpkt_send(ssh)) != 0)
464: fatal("%s: %s", __func__, ssh_err(r));
465:
1.260 markus 466: ssh->authctxt = &authctxt;
1.231 markus 467: ssh_dispatch_init(ssh, &input_userauth_error);
468: ssh_dispatch_set(ssh, SSH2_MSG_EXT_INFO, &input_userauth_ext_info);
469: ssh_dispatch_set(ssh, SSH2_MSG_SERVICE_ACCEPT, &input_userauth_service_accept);
1.263 markus 470: ssh_dispatch_run_fatal(ssh, DISPATCH_BLOCK, &authctxt.success); /* loop until success */
1.303 djm 471: pubkey_cleanup(ssh);
1.260 markus 472: ssh->authctxt = NULL;
1.20 markus 473:
1.231 markus 474: ssh_dispatch_range(ssh, SSH2_MSG_USERAUTH_MIN, SSH2_MSG_USERAUTH_MAX, NULL);
1.119 markus 475:
1.248 dtucker 476: if (!authctxt.success)
477: fatal("Authentication failed.");
1.109 markus 478: debug("Authentication succeeded (%s).", authctxt.method->name);
1.20 markus 479: }
1.119 markus 480:
1.231 markus 481: /* ARGSUSED */
1.302 djm 482: static int
1.261 markus 483: input_userauth_service_accept(int type, u_int32_t seq, struct ssh *ssh)
1.231 markus 484: {
485: int r;
486:
487: if (ssh_packet_remaining(ssh) > 0) {
488: char *reply;
489:
490: if ((r = sshpkt_get_cstring(ssh, &reply, NULL)) != 0)
491: goto out;
492: debug2("service_accept: %s", reply);
493: free(reply);
494: } else {
495: debug2("buggy server: service_accept w/o service");
496: }
497: if ((r = sshpkt_get_end(ssh)) != 0)
498: goto out;
499: debug("SSH2_MSG_SERVICE_ACCEPT received");
500:
501: /* initial userauth request */
1.295 djm 502: userauth_none(ssh);
1.231 markus 503:
504: ssh_dispatch_set(ssh, SSH2_MSG_EXT_INFO, &input_userauth_error);
505: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_SUCCESS, &input_userauth_success);
506: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_FAILURE, &input_userauth_failure);
507: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_BANNER, &input_userauth_banner);
508: r = 0;
509: out:
510: return r;
511: }
512:
513: /* ARGSUSED */
1.302 djm 514: static int
1.261 markus 515: input_userauth_ext_info(int type, u_int32_t seqnr, struct ssh *ssh)
1.231 markus 516: {
1.261 markus 517: return kex_input_ext_info(type, seqnr, ssh);
1.231 markus 518: }
519:
1.20 markus 520: void
1.295 djm 521: userauth(struct ssh *ssh, char *authlist)
1.51 markus 522: {
1.295 djm 523: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.278 markus 524:
1.170 djm 525: if (authctxt->method != NULL && authctxt->method->cleanup != NULL)
1.295 djm 526: authctxt->method->cleanup(ssh);
1.170 djm 527:
1.197 djm 528: free(authctxt->methoddata);
529: authctxt->methoddata = NULL;
1.51 markus 530: if (authlist == NULL) {
531: authlist = authctxt->authlist;
532: } else {
1.197 djm 533: free(authctxt->authlist);
1.51 markus 534: authctxt->authlist = authlist;
535: }
536: for (;;) {
537: Authmethod *method = authmethod_get(authlist);
538: if (method == NULL)
1.264 dtucker 539: fatal("%s@%s: Permission denied (%s).",
540: authctxt->server_user, authctxt->host, authlist);
1.51 markus 541: authctxt->method = method;
1.119 markus 542:
543: /* reset the per method handler */
1.278 markus 544: ssh_dispatch_range(ssh, SSH2_MSG_USERAUTH_PER_METHOD_MIN,
1.119 markus 545: SSH2_MSG_USERAUTH_PER_METHOD_MAX, NULL);
546:
547: /* and try new method */
1.295 djm 548: if (method->userauth(ssh) != 0) {
1.51 markus 549: debug2("we sent a %s packet, wait for reply", method->name);
550: break;
551: } else {
552: debug2("we did not send a packet, disable method");
553: method->enabled = NULL;
554: }
555: }
556: }
1.105 deraadt 557:
1.169 djm 558: /* ARGSUSED */
1.302 djm 559: static int
1.261 markus 560: input_userauth_error(int type, u_int32_t seq, struct ssh *ssh)
1.20 markus 561: {
1.295 djm 562: fatal("%s: bad message during authentication: type %d", __func__, type);
1.218 markus 563: return 0;
1.35 markus 564: }
1.105 deraadt 565:
1.169 djm 566: /* ARGSUSED */
1.302 djm 567: static int
1.261 markus 568: input_userauth_banner(int type, u_int32_t seq, struct ssh *ssh)
1.35 markus 569: {
1.295 djm 570: char *msg = NULL;
1.294 djm 571: size_t len;
572: int r;
1.126 deraadt 573:
1.246 djm 574: debug3("%s", __func__);
1.294 djm 575: if ((r = sshpkt_get_cstring(ssh, &msg, &len)) != 0 ||
1.295 djm 576: (r = sshpkt_get_cstring(ssh, NULL, NULL)) != 0)
1.294 djm 577: goto out;
1.246 djm 578: if (len > 0 && options.log_level >= SYSLOG_LEVEL_INFO)
579: fmprintf(stderr, "%s", msg);
1.294 djm 580: r = 0;
581: out:
1.246 djm 582: free(msg);
1.294 djm 583: return r;
1.20 markus 584: }
1.105 deraadt 585:
1.169 djm 586: /* ARGSUSED */
1.302 djm 587: static int
1.261 markus 588: input_userauth_success(int type, u_int32_t seq, struct ssh *ssh)
1.20 markus 589: {
1.260 markus 590: Authctxt *authctxt = ssh->authctxt;
1.172 djm 591:
1.20 markus 592: if (authctxt == NULL)
1.295 djm 593: fatal("%s: no authentication context", __func__);
1.197 djm 594: free(authctxt->authlist);
595: authctxt->authlist = NULL;
1.172 djm 596: if (authctxt->method != NULL && authctxt->method->cleanup != NULL)
1.295 djm 597: authctxt->method->cleanup(ssh);
1.197 djm 598: free(authctxt->methoddata);
599: authctxt->methoddata = NULL;
1.20 markus 600: authctxt->success = 1; /* break out */
1.218 markus 601: return 0;
1.20 markus 602: }
1.105 deraadt 603:
1.302 djm 604: #if 0
605: static int
1.261 markus 606: input_userauth_success_unexpected(int type, u_int32_t seq, struct ssh *ssh)
1.172 djm 607: {
1.260 markus 608: Authctxt *authctxt = ssh->authctxt;
1.172 djm 609:
610: if (authctxt == NULL)
611: fatal("%s: no authentication context", __func__);
612:
613: fatal("Unexpected authentication success during %s.",
614: authctxt->method->name);
1.218 markus 615: return 0;
1.172 djm 616: }
1.302 djm 617: #endif
1.172 djm 618:
1.169 djm 619: /* ARGSUSED */
1.302 djm 620: static int
1.261 markus 621: input_userauth_failure(int type, u_int32_t seq, struct ssh *ssh)
1.20 markus 622: {
1.260 markus 623: Authctxt *authctxt = ssh->authctxt;
1.20 markus 624: char *authlist = NULL;
1.278 markus 625: u_char partial;
1.20 markus 626:
627: if (authctxt == NULL)
628: fatal("input_userauth_failure: no authentication context");
629:
1.307 dtucker 630: if (sshpkt_get_cstring(ssh, &authlist, NULL) != 0 ||
631: sshpkt_get_u8(ssh, &partial) != 0 ||
632: sshpkt_get_end(ssh) != 0)
1.278 markus 633: goto out;
1.20 markus 634:
1.193 markus 635: if (partial != 0) {
1.247 dtucker 636: verbose("Authenticated with partial success.");
1.193 markus 637: /* reset state */
1.251 djm 638: pubkey_reset(authctxt);
1.193 markus 639: }
1.109 markus 640: debug("Authentications that can continue: %s", authlist);
1.20 markus 641:
1.295 djm 642: userauth(ssh, authlist);
1.278 markus 643: authlist = NULL;
644: out:
645: free(authlist);
1.218 markus 646: return 0;
1.51 markus 647: }
1.169 djm 648:
1.287 djm 649: /*
650: * Format an identity for logging including filename, key type, fingerprint
651: * and location (agent, etc.). Caller must free.
652: */
653: static char *
654: format_identity(Identity *id)
655: {
656: char *fp = NULL, *ret = NULL;
1.309 djm 657: const char *note = "";
1.287 djm 658:
659: if (id->key != NULL) {
660: fp = sshkey_fingerprint(id->key, options.fingerprint_hash,
661: SSH_FP_DEFAULT);
662: }
1.309 djm 663: if (id->key) {
664: if ((id->key->flags & SSHKEY_FLAG_EXT) != 0)
665: note = " token";
1.311 markus 666: else if (sshkey_is_sk(id->key))
1.319 naddy 667: note = " authenticator";
1.309 djm 668: }
1.287 djm 669: xasprintf(&ret, "%s %s%s%s%s%s%s",
670: id->filename,
671: id->key ? sshkey_type(id->key) : "", id->key ? " " : "",
672: fp ? fp : "",
1.309 djm 673: id->userprovided ? " explicit" : "", note,
1.287 djm 674: id->agent_fd != -1 ? " agent" : "");
675: free(fp);
676: return ret;
677: }
678:
1.169 djm 679: /* ARGSUSED */
1.302 djm 680: static int
1.261 markus 681: input_userauth_pk_ok(int type, u_int32_t seq, struct ssh *ssh)
1.51 markus 682: {
1.260 markus 683: Authctxt *authctxt = ssh->authctxt;
1.259 markus 684: struct sshkey *key = NULL;
1.117 markus 685: Identity *id = NULL;
1.287 djm 686: int pktype, found = 0, sent = 0;
1.278 markus 687: size_t blen;
1.287 djm 688: char *pkalg = NULL, *fp = NULL, *ident = NULL;
1.278 markus 689: u_char *pkblob = NULL;
690: int r;
1.51 markus 691:
692: if (authctxt == NULL)
693: fatal("input_userauth_pk_ok: no authentication context");
1.267 djm 694:
1.278 markus 695: if ((r = sshpkt_get_cstring(ssh, &pkalg, NULL)) != 0 ||
696: (r = sshpkt_get_string(ssh, &pkblob, &blen)) != 0 ||
697: (r = sshpkt_get_end(ssh)) != 0)
698: goto done;
1.51 markus 699:
1.278 markus 700: if ((pktype = sshkey_type_from_name(pkalg)) == KEY_UNSPEC) {
1.287 djm 701: debug("%s: server sent unknown pkalg %s", __func__, pkalg);
1.117 markus 702: goto done;
703: }
1.278 markus 704: if ((r = sshkey_from_blob(pkblob, blen, &key)) != 0) {
705: debug("no key from blob. pkalg %s: %s", pkalg, ssh_err(r));
1.117 markus 706: goto done;
707: }
708: if (key->type != pktype) {
709: error("input_userauth_pk_ok: type mismatch "
710: "for decoded key (received %d, expected %d)",
711: key->type, pktype);
712: goto done;
713: }
714:
1.127 markus 715: /*
716: * search keys in the reverse order, because last candidate has been
717: * moved to the end of the queue. this also avoids confusion by
718: * duplicate keys
719: */
1.136 henning 720: TAILQ_FOREACH_REVERSE(id, &authctxt->keys, idlist, next) {
1.278 markus 721: if (sshkey_equal(key, id->key)) {
1.287 djm 722: found = 1;
1.51 markus 723: break;
724: }
1.117 markus 725: }
1.287 djm 726: if (!found || id == NULL) {
727: fp = sshkey_fingerprint(key, options.fingerprint_hash,
728: SSH_FP_DEFAULT);
729: error("%s: server replied with unknown key: %s %s", __func__,
730: sshkey_type(key), fp == NULL ? "<ERROR>" : fp);
731: goto done;
732: }
733: ident = format_identity(id);
734: debug("Server accepts key: %s", ident);
1.295 djm 735: sent = sign_and_send_pubkey(ssh, id);
1.278 markus 736: r = 0;
737: done:
738: sshkey_free(key);
1.287 djm 739: free(ident);
740: free(fp);
1.197 djm 741: free(pkalg);
742: free(pkblob);
1.51 markus 743:
1.106 deraadt 744: /* try another method if we did not send a packet */
1.278 markus 745: if (r == 0 && sent == 0)
1.295 djm 746: userauth(ssh, NULL);
1.278 markus 747: return r;
1.20 markus 748: }
1.121 markus 749:
750: #ifdef GSSAPI
1.302 djm 751: static int
1.295 djm 752: userauth_gssapi(struct ssh *ssh)
1.121 markus 753: {
1.295 djm 754: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.121 markus 755: Gssctxt *gssctxt = NULL;
756: OM_uint32 min;
1.278 markus 757: int r, ok = 0;
1.302 djm 758: gss_OID mech = NULL;
1.121 markus 759:
760: /* Try one GSSAPI method at a time, rather than sending them all at
761: * once. */
762:
1.302 djm 763: if (authctxt->gss_supported_mechs == NULL)
764: gss_indicate_mechs(&min, &authctxt->gss_supported_mechs);
1.121 markus 765:
1.302 djm 766: /* Check to see whether the mechanism is usable before we offer it */
767: while (authctxt->mech_tried < authctxt->gss_supported_mechs->count &&
768: !ok) {
769: mech = &authctxt->gss_supported_mechs->
770: elements[authctxt->mech_tried];
1.121 markus 771: /* My DER encoding requires length<128 */
1.302 djm 772: if (mech->length < 128 && ssh_gssapi_check_mechanism(&gssctxt,
773: mech, authctxt->host)) {
1.121 markus 774: ok = 1; /* Mechanism works */
775: } else {
1.302 djm 776: authctxt->mech_tried++;
1.121 markus 777: }
778: }
779:
1.302 djm 780: if (!ok || mech == NULL)
1.139 djm 781: return 0;
1.121 markus 782:
783: authctxt->methoddata=(void *)gssctxt;
784:
1.278 markus 785: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
786: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
787: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
788: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
789: (r = sshpkt_put_u32(ssh, 1)) != 0 ||
1.302 djm 790: (r = sshpkt_put_u32(ssh, (mech->length) + 2)) != 0 ||
1.278 markus 791: (r = sshpkt_put_u8(ssh, SSH_GSS_OIDTYPE)) != 0 ||
1.302 djm 792: (r = sshpkt_put_u8(ssh, mech->length)) != 0 ||
793: (r = sshpkt_put(ssh, mech->elements, mech->length)) != 0 ||
1.278 markus 794: (r = sshpkt_send(ssh)) != 0)
795: fatal("%s: %s", __func__, ssh_err(r));
796:
797: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_RESPONSE, &input_gssapi_response);
798: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_TOKEN, &input_gssapi_token);
799: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_ERROR, &input_gssapi_error);
800: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_ERRTOK, &input_gssapi_errtok);
1.121 markus 801:
1.302 djm 802: authctxt->mech_tried++; /* Move along to next candidate */
1.121 markus 803:
804: return 1;
805: }
806:
1.302 djm 807: static void
808: userauth_gssapi_cleanup(struct ssh *ssh)
809: {
810: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
811: Gssctxt *gssctxt = (Gssctxt *)authctxt->methoddata;
812:
813: ssh_gssapi_delete_ctx(&gssctxt);
814: authctxt->methoddata = NULL;
815:
816: free(authctxt->gss_supported_mechs);
817: authctxt->gss_supported_mechs = NULL;
818: }
819:
1.130 markus 820: static OM_uint32
1.262 djm 821: process_gssapi_token(struct ssh *ssh, gss_buffer_t recv_tok)
1.130 markus 822: {
1.260 markus 823: Authctxt *authctxt = ssh->authctxt;
1.130 markus 824: Gssctxt *gssctxt = authctxt->methoddata;
825: gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
1.142 djm 826: gss_buffer_desc mic = GSS_C_EMPTY_BUFFER;
827: gss_buffer_desc gssbuf;
1.132 markus 828: OM_uint32 status, ms, flags;
1.278 markus 829: int r;
1.133 djm 830:
1.130 markus 831: status = ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
1.132 markus 832: recv_tok, &send_tok, &flags);
1.130 markus 833:
834: if (send_tok.length > 0) {
1.278 markus 835: u_char type = GSS_ERROR(status) ?
836: SSH2_MSG_USERAUTH_GSSAPI_ERRTOK :
837: SSH2_MSG_USERAUTH_GSSAPI_TOKEN;
838:
839: if ((r = sshpkt_start(ssh, type)) != 0 ||
840: (r = sshpkt_put_string(ssh, send_tok.value,
841: send_tok.length)) != 0 ||
842: (r = sshpkt_send(ssh)) != 0)
843: fatal("%s: %s", __func__, ssh_err(r));
1.133 djm 844:
1.130 markus 845: gss_release_buffer(&ms, &send_tok);
846: }
1.133 djm 847:
1.130 markus 848: if (status == GSS_S_COMPLETE) {
1.132 markus 849: /* send either complete or MIC, depending on mechanism */
850: if (!(flags & GSS_C_INTEG_FLAG)) {
1.278 markus 851: if ((r = sshpkt_start(ssh,
852: SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE)) != 0 ||
853: (r = sshpkt_send(ssh)) != 0)
854: fatal("%s: %s", __func__, ssh_err(r));
1.132 markus 855: } else {
1.278 markus 856: struct sshbuf *b;
857:
858: if ((b = sshbuf_new()) == NULL)
859: fatal("%s: sshbuf_new failed", __func__);
860: ssh_gssapi_buildmic(b, authctxt->server_user,
1.132 markus 861: authctxt->service, "gssapi-with-mic");
862:
1.278 markus 863: if ((gssbuf.value = sshbuf_mutable_ptr(b)) == NULL)
864: fatal("%s: sshbuf_mutable_ptr failed", __func__);
865: gssbuf.length = sshbuf_len(b);
1.133 djm 866:
1.132 markus 867: status = ssh_gssapi_sign(gssctxt, &gssbuf, &mic);
1.133 djm 868:
1.132 markus 869: if (!GSS_ERROR(status)) {
1.278 markus 870: if ((r = sshpkt_start(ssh,
871: SSH2_MSG_USERAUTH_GSSAPI_MIC)) != 0 ||
872: (r = sshpkt_put_string(ssh, mic.value,
873: mic.length)) != 0 ||
874: (r = sshpkt_send(ssh)) != 0)
875: fatal("%s: %s", __func__, ssh_err(r));
1.132 markus 876: }
1.133 djm 877:
1.278 markus 878: sshbuf_free(b);
1.132 markus 879: gss_release_buffer(&ms, &mic);
1.133 djm 880: }
1.130 markus 881: }
1.133 djm 882:
1.130 markus 883: return status;
884: }
885:
1.169 djm 886: /* ARGSUSED */
1.302 djm 887: static int
1.261 markus 888: input_gssapi_response(int type, u_int32_t plen, struct ssh *ssh)
1.121 markus 889: {
1.260 markus 890: Authctxt *authctxt = ssh->authctxt;
1.121 markus 891: Gssctxt *gssctxt;
1.278 markus 892: size_t oidlen;
893: u_char *oidv = NULL;
894: int r;
1.121 markus 895:
896: if (authctxt == NULL)
897: fatal("input_gssapi_response: no authentication context");
898: gssctxt = authctxt->methoddata;
899:
900: /* Setup our OID */
1.278 markus 901: if ((r = sshpkt_get_string(ssh, &oidv, &oidlen)) != 0)
902: goto done;
1.121 markus 903:
1.129 markus 904: if (oidlen <= 2 ||
905: oidv[0] != SSH_GSS_OIDTYPE ||
906: oidv[1] != oidlen - 2) {
907: debug("Badly encoded mechanism OID received");
1.296 djm 908: userauth(ssh, NULL);
1.278 markus 909: goto ok;
1.121 markus 910: }
1.129 markus 911:
912: if (!ssh_gssapi_check_oid(gssctxt, oidv + 2, oidlen - 2))
913: fatal("Server returned different OID than expected");
1.121 markus 914:
1.278 markus 915: if ((r = sshpkt_get_end(ssh)) != 0)
916: goto done;
1.121 markus 917:
1.262 djm 918: if (GSS_ERROR(process_gssapi_token(ssh, GSS_C_NO_BUFFER))) {
1.121 markus 919: /* Start again with next method on list */
920: debug("Trying to start again");
1.296 djm 921: userauth(ssh, NULL);
1.278 markus 922: goto ok;
1.121 markus 923: }
1.278 markus 924: ok:
925: r = 0;
926: done:
927: free(oidv);
928: return r;
1.121 markus 929: }
930:
1.169 djm 931: /* ARGSUSED */
1.302 djm 932: static int
1.261 markus 933: input_gssapi_token(int type, u_int32_t plen, struct ssh *ssh)
1.121 markus 934: {
1.260 markus 935: Authctxt *authctxt = ssh->authctxt;
1.121 markus 936: gss_buffer_desc recv_tok;
1.278 markus 937: u_char *p = NULL;
938: size_t len;
1.130 markus 939: OM_uint32 status;
1.278 markus 940: int r;
1.121 markus 941:
942: if (authctxt == NULL)
943: fatal("input_gssapi_response: no authentication context");
944:
1.278 markus 945: if ((r = sshpkt_get_string(ssh, &p, &len)) != 0 ||
946: (r = sshpkt_get_end(ssh)) != 0)
947: goto out;
1.121 markus 948:
1.278 markus 949: recv_tok.value = p;
950: recv_tok.length = len;
1.262 djm 951: status = process_gssapi_token(ssh, &recv_tok);
1.121 markus 952:
1.278 markus 953: /* Start again with the next method in the list */
1.121 markus 954: if (GSS_ERROR(status)) {
1.296 djm 955: userauth(ssh, NULL);
1.278 markus 956: /* ok */
1.121 markus 957: }
1.278 markus 958: r = 0;
959: out:
960: free(p);
961: return r;
1.121 markus 962: }
963:
1.169 djm 964: /* ARGSUSED */
1.302 djm 965: static int
1.261 markus 966: input_gssapi_errtok(int type, u_int32_t plen, struct ssh *ssh)
1.121 markus 967: {
1.260 markus 968: Authctxt *authctxt = ssh->authctxt;
1.121 markus 969: Gssctxt *gssctxt;
970: gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
971: gss_buffer_desc recv_tok;
1.194 djm 972: OM_uint32 ms;
1.278 markus 973: u_char *p = NULL;
974: size_t len;
975: int r;
1.121 markus 976:
977: if (authctxt == NULL)
978: fatal("input_gssapi_response: no authentication context");
979: gssctxt = authctxt->methoddata;
980:
1.278 markus 981: if ((r = sshpkt_get_string(ssh, &p, &len)) != 0 ||
982: (r = sshpkt_get_end(ssh)) != 0) {
983: free(p);
984: return r;
985: }
1.121 markus 986:
987: /* Stick it into GSSAPI and see what it says */
1.278 markus 988: recv_tok.value = p;
989: recv_tok.length = len;
1.194 djm 990: (void)ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
1.140 djm 991: &recv_tok, &send_tok, NULL);
1.278 markus 992: free(p);
1.121 markus 993: gss_release_buffer(&ms, &send_tok);
994:
995: /* Server will be returning a failed packet after this one */
1.220 djm 996: return 0;
1.121 markus 997: }
998:
1.169 djm 999: /* ARGSUSED */
1.302 djm 1000: static int
1.261 markus 1001: input_gssapi_error(int type, u_int32_t plen, struct ssh *ssh)
1.121 markus 1002: {
1.278 markus 1003: char *msg = NULL;
1004: char *lang = NULL;
1005: int r;
1.121 markus 1006:
1.278 markus 1007: if ((r = sshpkt_get_u32(ssh, NULL)) != 0 || /* maj */
1008: (r = sshpkt_get_u32(ssh, NULL)) != 0 || /* min */
1009: (r = sshpkt_get_cstring(ssh, &msg, NULL)) != 0 ||
1010: (r = sshpkt_get_cstring(ssh, &lang, NULL)) != 0)
1011: goto out;
1012: r = sshpkt_get_end(ssh);
1.143 stevesk 1013: debug("Server GSSAPI Error:\n%s", msg);
1.278 markus 1014: out:
1.197 djm 1015: free(msg);
1016: free(lang);
1.278 markus 1017: return r;
1.121 markus 1018: }
1019: #endif /* GSSAPI */
1.20 markus 1020:
1.302 djm 1021: static int
1.295 djm 1022: userauth_none(struct ssh *ssh)
1.23 markus 1023: {
1.295 djm 1024: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.278 markus 1025: int r;
1026:
1.23 markus 1027: /* initial userauth request */
1.278 markus 1028: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1029: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1030: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1031: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1032: (r = sshpkt_send(ssh)) != 0)
1033: fatal("%s: %s", __func__, ssh_err(r));
1.23 markus 1034: return 1;
1035: }
1036:
1.302 djm 1037: static int
1.295 djm 1038: userauth_passwd(struct ssh *ssh)
1.1 markus 1039: {
1.295 djm 1040: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.290 djm 1041: char *password, *prompt = NULL;
1.175 dtucker 1042: const char *host = options.host_key_alias ? options.host_key_alias :
1043: authctxt->host;
1.278 markus 1044: int r;
1.6 markus 1045:
1.292 djm 1046: if (authctxt->attempt_passwd++ >= options.number_of_password_prompts)
1.6 markus 1047: return 0;
1.13 todd 1048:
1.292 djm 1049: if (authctxt->attempt_passwd != 1)
1.13 todd 1050: error("Permission denied, please try again.");
1.1 markus 1051:
1.290 djm 1052: xasprintf(&prompt, "%s@%s's password: ", authctxt->server_user, host);
1.1 markus 1053: password = read_passphrase(prompt, 0);
1.278 markus 1054: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1055: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1056: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1057: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1058: (r = sshpkt_put_u8(ssh, 0)) != 0 ||
1059: (r = sshpkt_put_cstring(ssh, password)) != 0 ||
1060: (r = sshpkt_add_padding(ssh, 64)) != 0 ||
1061: (r = sshpkt_send(ssh)) != 0)
1062: fatal("%s: %s", __func__, ssh_err(r));
1.99 markus 1063:
1.290 djm 1064: free(prompt);
1065: if (password != NULL)
1.278 markus 1066: freezero(password, strlen(password));
1067:
1068: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
1.99 markus 1069: &input_userauth_passwd_changereq);
1070:
1.1 markus 1071: return 1;
1072: }
1.169 djm 1073:
1.99 markus 1074: /*
1075: * parse PASSWD_CHANGEREQ, prompt user and send SSH2_MSG_USERAUTH_REQUEST
1076: */
1.169 djm 1077: /* ARGSUSED */
1.302 djm 1078: static int
1.261 markus 1079: input_userauth_passwd_changereq(int type, u_int32_t seqnr, struct ssh *ssh)
1.99 markus 1080: {
1.260 markus 1081: Authctxt *authctxt = ssh->authctxt;
1.278 markus 1082: char *info = NULL, *lang = NULL, *password = NULL, *retype = NULL;
1.266 dtucker 1083: char prompt[256];
1.252 djm 1084: const char *host;
1.278 markus 1085: int r;
1.99 markus 1086:
1087: debug2("input_userauth_passwd_changereq");
1088:
1089: if (authctxt == NULL)
1090: fatal("input_userauth_passwd_changereq: "
1091: "no authentication context");
1.252 djm 1092: host = options.host_key_alias ? options.host_key_alias : authctxt->host;
1.99 markus 1093:
1.278 markus 1094: if ((r = sshpkt_get_cstring(ssh, &info, NULL)) != 0 ||
1095: (r = sshpkt_get_cstring(ssh, &lang, NULL)) != 0)
1096: goto out;
1.99 markus 1097: if (strlen(info) > 0)
1.116 itojun 1098: logit("%s", info);
1.278 markus 1099: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1100: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1101: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1102: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1103: (r = sshpkt_put_u8(ssh, 1)) != 0) /* additional info */
1104: goto out;
1105:
1.104 deraadt 1106: snprintf(prompt, sizeof(prompt),
1.99 markus 1107: "Enter %.30s@%.128s's old password: ",
1.175 dtucker 1108: authctxt->server_user, host);
1.99 markus 1109: password = read_passphrase(prompt, 0);
1.278 markus 1110: if ((r = sshpkt_put_cstring(ssh, password)) != 0)
1111: goto out;
1112:
1113: freezero(password, strlen(password));
1.99 markus 1114: password = NULL;
1115: while (password == NULL) {
1.104 deraadt 1116: snprintf(prompt, sizeof(prompt),
1.99 markus 1117: "Enter %.30s@%.128s's new password: ",
1.175 dtucker 1118: authctxt->server_user, host);
1.99 markus 1119: password = read_passphrase(prompt, RP_ALLOW_EOF);
1120: if (password == NULL) {
1121: /* bail out */
1.278 markus 1122: r = 0;
1123: goto out;
1.99 markus 1124: }
1.104 deraadt 1125: snprintf(prompt, sizeof(prompt),
1.99 markus 1126: "Retype %.30s@%.128s's new password: ",
1.175 dtucker 1127: authctxt->server_user, host);
1.99 markus 1128: retype = read_passphrase(prompt, 0);
1129: if (strcmp(password, retype) != 0) {
1.278 markus 1130: freezero(password, strlen(password));
1.116 itojun 1131: logit("Mismatch; try again, EOF to quit.");
1.99 markus 1132: password = NULL;
1133: }
1.278 markus 1134: freezero(retype, strlen(retype));
1.99 markus 1135: }
1.278 markus 1136: if ((r = sshpkt_put_cstring(ssh, password)) != 0 ||
1137: (r = sshpkt_add_padding(ssh, 64)) != 0 ||
1138: (r = sshpkt_send(ssh)) != 0)
1139: goto out;
1.104 deraadt 1140:
1.278 markus 1141: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
1.99 markus 1142: &input_userauth_passwd_changereq);
1.278 markus 1143: r = 0;
1144: out:
1145: if (password)
1146: freezero(password, strlen(password));
1147: free(info);
1148: free(lang);
1149: return r;
1.117 markus 1150: }
1151:
1.272 djm 1152: /*
1153: * Select an algorithm for publickey signatures.
1154: * Returns algorithm (caller must free) or NULL if no mutual algorithm found.
1155: *
1156: * Call with ssh==NULL to ignore server-sig-algs extension list and
1157: * only attempt with the key's base signature type.
1158: */
1159: static char *
1160: key_sig_algorithm(struct ssh *ssh, const struct sshkey *key)
1.231 markus 1161: {
1.274 djm 1162: char *allowed, *oallowed, *cp, *tmp, *alg = NULL;
1.231 markus 1163:
1.272 djm 1164: /*
1165: * The signature algorithm will only differ from the key algorithm
1166: * for RSA keys/certs and when the server advertises support for
1167: * newer (SHA2) algorithms.
1168: */
1169: if (ssh == NULL || ssh->kex->server_sig_algs == NULL ||
1.288 djm 1170: (key->type != KEY_RSA && key->type != KEY_RSA_CERT) ||
1171: (key->type == KEY_RSA_CERT && (datafellows & SSH_BUG_SIGTYPE))) {
1.272 djm 1172: /* Filter base key signature alg against our configuration */
1.279 markus 1173: return match_list(sshkey_ssh_name(key),
1.272 djm 1174: options.pubkey_key_types, NULL);
1.231 markus 1175: }
1176:
1.272 djm 1177: /*
1178: * For RSA keys/certs, since these might have a different sig type:
1179: * find the first entry in PubkeyAcceptedKeyTypes of the right type
1180: * that also appears in the supported signature algorithms list from
1181: * the server.
1182: */
1183: oallowed = allowed = xstrdup(options.pubkey_key_types);
1184: while ((cp = strsep(&allowed, ",")) != NULL) {
1185: if (sshkey_type_from_name(cp) != key->type)
1186: continue;
1.323 djm 1187: tmp = match_list(sshkey_sigalg_by_name(cp),
1188: ssh->kex->server_sig_algs, NULL);
1.274 djm 1189: if (tmp != NULL)
1190: alg = xstrdup(cp);
1191: free(tmp);
1.272 djm 1192: if (alg != NULL)
1193: break;
1.269 djm 1194: }
1.272 djm 1195: free(oallowed);
1196: return alg;
1.269 djm 1197: }
1198:
1.117 markus 1199: static int
1.214 djm 1200: identity_sign(struct identity *id, u_char **sigp, size_t *lenp,
1.272 djm 1201: const u_char *data, size_t datalen, u_int compat, const char *alg)
1.117 markus 1202: {
1.309 djm 1203: struct sshkey *sign_key = NULL, *prv = NULL;
1204: int r = SSH_ERR_INTERNAL_ERROR;
1.312 djm 1205: struct notifier_ctx *notifier = NULL;
1.325 djm 1206: char *fp = NULL, *pin = NULL, *prompt = NULL;
1.309 djm 1207:
1208: *sigp = NULL;
1209: *lenp = 0;
1.99 markus 1210:
1.272 djm 1211: /* The agent supports this key. */
1.269 djm 1212: if (id->key != NULL && id->agent_fd != -1) {
1.272 djm 1213: return ssh_agent_sign(id->agent_fd, id->key, sigp, lenp,
1214: data, datalen, alg, compat);
1.269 djm 1215: }
1.214 djm 1216:
1.117 markus 1217: /*
1.272 djm 1218: * We have already loaded the private key or the private key is
1219: * stored in external hardware.
1.117 markus 1220: */
1.255 djm 1221: if (id->key != NULL &&
1.272 djm 1222: (id->isprivate || (id->key->flags & SSHKEY_FLAG_EXT))) {
1.309 djm 1223: sign_key = id->key;
1224: } else {
1225: /* Load the private key from the file. */
1226: if ((prv = load_identity_file(id)) == NULL)
1227: return SSH_ERR_KEY_NOT_FOUND;
1228: if (id->key != NULL && !sshkey_equal_public(prv, id->key)) {
1229: error("%s: private key %s contents do not match public",
1230: __func__, id->filename);
1231: r = SSH_ERR_KEY_NOT_FOUND;
1232: goto out;
1233: }
1234: sign_key = prv;
1.325 djm 1235: if (sshkey_is_sk(sign_key)) {
1236: if ((sign_key->sk_flags &
1237: SSH_SK_USER_VERIFICATION_REQD)) {
1238: xasprintf(&prompt, "Enter PIN for %s key %s: ",
1239: sshkey_type(sign_key), id->filename);
1240: pin = read_passphrase(prompt, 0);
1241: }
1242: if ((sign_key->sk_flags & SSH_SK_USER_PRESENCE_REQD)) {
1243: /* XXX should batch mode just skip these? */
1244: if ((fp = sshkey_fingerprint(sign_key,
1245: options.fingerprint_hash,
1246: SSH_FP_DEFAULT)) == NULL)
1247: fatal("%s: fingerprint", __func__);
1248: notifier = notify_start(options.batch_mode,
1249: "Confirm user presence for key %s %s",
1250: sshkey_type(sign_key), fp);
1251: free(fp);
1252: }
1.312 djm 1253: }
1.272 djm 1254: }
1.310 djm 1255: if ((r = sshkey_sign(sign_key, sigp, lenp, data, datalen,
1.325 djm 1256: alg, options.sk_provider, pin, compat)) != 0) {
1.309 djm 1257: debug("%s: sshkey_sign: %s", __func__, ssh_err(r));
1258: goto out;
1259: }
1260: /*
1261: * PKCS#11 tokens may not support all signature algorithms,
1262: * so check what we get back.
1263: */
1264: if ((r = sshkey_check_sigtype(*sigp, *lenp, alg)) != 0) {
1265: debug("%s: sshkey_check_sigtype: %s", __func__, ssh_err(r));
1266: goto out;
1.265 djm 1267: }
1.309 djm 1268: /* success */
1269: r = 0;
1270: out:
1.325 djm 1271: free(prompt);
1272: if (pin != NULL)
1273: freezero(pin, strlen(pin));
1.314 djm 1274: notify_complete(notifier);
1.214 djm 1275: sshkey_free(prv);
1.269 djm 1276: return r;
1.51 markus 1277: }
1278:
1.76 itojun 1279: static int
1.255 djm 1280: id_filename_matches(Identity *id, Identity *private_id)
1281: {
1282: const char *suffixes[] = { ".pub", "-cert.pub", NULL };
1283: size_t len = strlen(id->filename), plen = strlen(private_id->filename);
1284: size_t i, slen;
1285:
1286: if (strcmp(id->filename, private_id->filename) == 0)
1287: return 1;
1288: for (i = 0; suffixes[i]; i++) {
1289: slen = strlen(suffixes[i]);
1290: if (len > slen && plen == len - slen &&
1291: strcmp(id->filename + (len - slen), suffixes[i]) == 0 &&
1292: memcmp(id->filename, private_id->filename, plen) == 0)
1293: return 1;
1294: }
1295: return 0;
1296: }
1297:
1298: static int
1.295 djm 1299: sign_and_send_pubkey(struct ssh *ssh, Identity *id)
1.1 markus 1300: {
1.295 djm 1301: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.272 djm 1302: struct sshbuf *b = NULL;
1303: Identity *private_id, *sign_id = NULL;
1304: u_char *signature = NULL;
1305: size_t slen = 0, skip = 0;
1306: int r, fallback_sigtype, sent = 0;
1307: char *alg = NULL, *fp = NULL;
1308: const char *loc = "";
1.1 markus 1309:
1.222 djm 1310: if ((fp = sshkey_fingerprint(id->key, options.fingerprint_hash,
1311: SSH_FP_DEFAULT)) == NULL)
1312: return 0;
1.51 markus 1313:
1.272 djm 1314: debug3("%s: %s %s", __func__, sshkey_type(id->key), fp);
1.1 markus 1315:
1.227 djm 1316: /*
1317: * If the key is an certificate, try to find a matching private key
1318: * and use it to complete the signature.
1.241 djm 1319: * If no such private key exists, fall back to trying the certificate
1320: * key itself in case it has a private half already loaded.
1.272 djm 1321: * This will try to set sign_id to the private key that will perform
1322: * the signature.
1.227 djm 1323: */
1.272 djm 1324: if (sshkey_is_cert(id->key)) {
1.227 djm 1325: TAILQ_FOREACH(private_id, &authctxt->keys, next) {
1326: if (sshkey_equal_public(id->key, private_id->key) &&
1327: id->key->type != private_id->key->type) {
1.272 djm 1328: sign_id = private_id;
1.227 djm 1329: break;
1330: }
1331: }
1.255 djm 1332: /*
1333: * Exact key matches are preferred, but also allow
1334: * filename matches for non-PKCS#11/agent keys that
1335: * didn't load public keys. This supports the case
1336: * of keeping just a private key file and public
1337: * certificate on disk.
1338: */
1.272 djm 1339: if (sign_id == NULL &&
1340: !id->isprivate && id->agent_fd == -1 &&
1.255 djm 1341: (id->key->flags & SSHKEY_FLAG_EXT) == 0) {
1342: TAILQ_FOREACH(private_id, &authctxt->keys, next) {
1343: if (private_id->key == NULL &&
1344: id_filename_matches(id, private_id)) {
1.272 djm 1345: sign_id = private_id;
1.255 djm 1346: break;
1347: }
1348: }
1349: }
1.272 djm 1350: if (sign_id != NULL) {
1.227 djm 1351: debug2("%s: using private key \"%s\"%s for "
1352: "certificate", __func__, id->filename,
1353: id->agent_fd != -1 ? " from agent" : "");
1354: } else {
1.240 djm 1355: debug("%s: no separate private key for certificate "
1.227 djm 1356: "\"%s\"", __func__, id->filename);
1357: }
1358: }
1359:
1.272 djm 1360: /*
1361: * If the above didn't select another identity to do the signing
1362: * then default to the one we started with.
1363: */
1364: if (sign_id == NULL)
1365: sign_id = id;
1366:
1367: /* assemble and sign data */
1368: for (fallback_sigtype = 0; fallback_sigtype <= 1; fallback_sigtype++) {
1369: free(alg);
1370: slen = 0;
1371: signature = NULL;
1372: if ((alg = key_sig_algorithm(fallback_sigtype ? NULL : ssh,
1373: id->key)) == NULL) {
1374: error("%s: no mutual signature supported", __func__);
1375: goto out;
1376: }
1.315 djm 1377: debug3("%s: signing using %s %s", __func__, alg, fp);
1.272 djm 1378:
1379: sshbuf_free(b);
1380: if ((b = sshbuf_new()) == NULL)
1381: fatal("%s: sshbuf_new failed", __func__);
1382: if (datafellows & SSH_OLD_SESSIONID) {
1383: if ((r = sshbuf_put(b, session_id2,
1384: session_id2_len)) != 0) {
1385: fatal("%s: sshbuf_put: %s",
1386: __func__, ssh_err(r));
1387: }
1388: } else {
1389: if ((r = sshbuf_put_string(b, session_id2,
1390: session_id2_len)) != 0) {
1391: fatal("%s: sshbuf_put_string: %s",
1392: __func__, ssh_err(r));
1393: }
1394: }
1.278 markus 1395: skip = sshbuf_len(b);
1.272 djm 1396: if ((r = sshbuf_put_u8(b, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1397: (r = sshbuf_put_cstring(b, authctxt->server_user)) != 0 ||
1398: (r = sshbuf_put_cstring(b, authctxt->service)) != 0 ||
1399: (r = sshbuf_put_cstring(b, authctxt->method->name)) != 0 ||
1400: (r = sshbuf_put_u8(b, 1)) != 0 ||
1401: (r = sshbuf_put_cstring(b, alg)) != 0 ||
1402: (r = sshkey_puts(id->key, b)) != 0) {
1403: fatal("%s: assemble signed data: %s",
1404: __func__, ssh_err(r));
1405: }
1406:
1407: /* generate signature */
1408: r = identity_sign(sign_id, &signature, &slen,
1409: sshbuf_ptr(b), sshbuf_len(b), datafellows, alg);
1410: if (r == 0)
1411: break;
1412: else if (r == SSH_ERR_KEY_NOT_FOUND)
1413: goto out; /* soft failure */
1414: else if (r == SSH_ERR_SIGN_ALG_UNSUPPORTED &&
1415: !fallback_sigtype) {
1416: if (sign_id->agent_fd != -1)
1417: loc = "agent ";
1418: else if ((sign_id->key->flags & SSHKEY_FLAG_EXT) != 0)
1419: loc = "token ";
1420: logit("%skey %s %s returned incorrect signature type",
1421: loc, sshkey_type(id->key), fp);
1422: continue;
1423: }
1.315 djm 1424: error("%s: signing failed for %s \"%s\"%s: %s", __func__,
1425: sshkey_type(sign_id->key), sign_id->filename,
1426: id->agent_fd != -1 ? " from agent" : "", ssh_err(r));
1.272 djm 1427: goto out;
1.17 markus 1428: }
1.272 djm 1429: if (slen == 0 || signature == NULL) /* shouldn't happen */
1430: fatal("%s: no signature", __func__);
1.51 markus 1431:
1.1 markus 1432: /* append signature */
1.272 djm 1433: if ((r = sshbuf_put_string(b, signature, slen)) != 0)
1434: fatal("%s: append signature: %s", __func__, ssh_err(r));
1.1 markus 1435:
1.272 djm 1436: #ifdef DEBUG_PK
1437: sshbuf_dump(b, stderr);
1438: #endif
1.1 markus 1439: /* skip session id and packet type */
1.272 djm 1440: if ((r = sshbuf_consume(b, skip + 1)) != 0)
1441: fatal("%s: consume: %s", __func__, ssh_err(r));
1.1 markus 1442:
1443: /* put remaining data from buffer into packet */
1.272 djm 1444: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1445: (r = sshpkt_putb(ssh, b)) != 0 ||
1446: (r = sshpkt_send(ssh)) != 0)
1447: fatal("%s: enqueue request: %s", __func__, ssh_err(r));
1448:
1449: /* success */
1450: sent = 1;
1.17 markus 1451:
1.272 djm 1452: out:
1453: free(fp);
1454: free(alg);
1455: sshbuf_free(b);
1456: freezero(signature, slen);
1457: return sent;
1.16 markus 1458: }
1459:
1.76 itojun 1460: static int
1.295 djm 1461: send_pubkey_test(struct ssh *ssh, Identity *id)
1.20 markus 1462: {
1.295 djm 1463: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.272 djm 1464: u_char *blob = NULL;
1465: char *alg = NULL;
1.278 markus 1466: size_t bloblen;
1467: u_int have_sig = 0;
1468: int sent = 0, r;
1.20 markus 1469:
1.272 djm 1470: if ((alg = key_sig_algorithm(ssh, id->key)) == NULL) {
1471: debug("%s: no mutual signature algorithm", __func__);
1472: goto out;
1473: }
1.16 markus 1474:
1.278 markus 1475: if ((r = sshkey_to_blob(id->key, &blob, &bloblen)) != 0) {
1.51 markus 1476: /* we cannot handle this key */
1.272 djm 1477: debug3("%s: cannot handle key", __func__);
1478: goto out;
1.16 markus 1479: }
1.51 markus 1480: /* register callback for USERAUTH_PK_OK message */
1.278 markus 1481: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_PK_OK, &input_userauth_pk_ok);
1.51 markus 1482:
1.278 markus 1483: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1484: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1485: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1486: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1487: (r = sshpkt_put_u8(ssh, have_sig)) != 0 ||
1488: (r = sshpkt_put_cstring(ssh, alg)) != 0 ||
1489: (r = sshpkt_put_string(ssh, blob, bloblen)) != 0 ||
1490: (r = sshpkt_send(ssh)) != 0)
1491: fatal("%s: %s", __func__, ssh_err(r));
1.272 djm 1492: sent = 1;
1.278 markus 1493:
1494: out:
1.272 djm 1495: free(alg);
1.197 djm 1496: free(blob);
1.272 djm 1497: return sent;
1.51 markus 1498: }
1499:
1.259 markus 1500: static struct sshkey *
1.229 jcs 1501: load_identity_file(Identity *id)
1.51 markus 1502: {
1.259 markus 1503: struct sshkey *private = NULL;
1.229 jcs 1504: char prompt[300], *passphrase, *comment;
1.308 dtucker 1505: int r, quit = 0, i;
1.52 markus 1506: struct stat st;
1.16 markus 1507:
1.306 deraadt 1508: if (stat(id->filename, &st) == -1) {
1.229 jcs 1509: (id->userprovided ? logit : debug3)("no such identity: %s: %s",
1510: id->filename, strerror(errno));
1.52 markus 1511: return NULL;
1512: }
1.214 djm 1513: snprintf(prompt, sizeof prompt,
1.229 jcs 1514: "Enter passphrase for key '%.100s': ", id->filename);
1.214 djm 1515: for (i = 0; i <= options.number_of_password_prompts; i++) {
1516: if (i == 0)
1517: passphrase = "";
1518: else {
1.20 markus 1519: passphrase = read_passphrase(prompt, 0);
1.214 djm 1520: if (*passphrase == '\0') {
1.20 markus 1521: debug2("no passphrase given, try next key");
1.214 djm 1522: free(passphrase);
1523: break;
1524: }
1525: }
1.229 jcs 1526: switch ((r = sshkey_load_private_type(KEY_UNSPEC, id->filename,
1.308 dtucker 1527: passphrase, &private, &comment))) {
1.214 djm 1528: case 0:
1529: break;
1530: case SSH_ERR_KEY_WRONG_PASSPHRASE:
1531: if (options.batch_mode) {
1532: quit = 1;
1533: break;
1534: }
1.215 djm 1535: if (i != 0)
1536: debug2("bad passphrase given, try again...");
1.214 djm 1537: break;
1538: case SSH_ERR_SYSTEM_ERROR:
1539: if (errno == ENOENT) {
1540: debug2("Load key \"%s\": %s",
1.229 jcs 1541: id->filename, ssh_err(r));
1.51 markus 1542: quit = 1;
1.214 djm 1543: break;
1.20 markus 1544: }
1.214 djm 1545: /* FALLTHROUGH */
1546: default:
1.229 jcs 1547: error("Load key \"%s\": %s", id->filename, ssh_err(r));
1.214 djm 1548: quit = 1;
1549: break;
1550: }
1.311 markus 1551: if (private != NULL && sshkey_is_sk(private) &&
1.309 djm 1552: options.sk_provider == NULL) {
1.319 naddy 1553: debug("key \"%s\" is an authenticator-hosted key, "
1554: "but no provider specified", id->filename);
1.309 djm 1555: sshkey_free(private);
1556: private = NULL;
1557: quit = 1;
1558: }
1.230 djm 1559: if (!quit && private != NULL && id->agent_fd == -1 &&
1.229 jcs 1560: !(id->key && id->isprivate))
1561: maybe_add_key_to_agent(id->filename, private, comment,
1562: passphrase);
1.278 markus 1563: if (i > 0)
1564: freezero(passphrase, strlen(passphrase));
1.232 mmcc 1565: free(comment);
1.214 djm 1566: if (private != NULL || quit)
1567: break;
1.16 markus 1568: }
1.51 markus 1569: return private;
1570: }
1571:
1.272 djm 1572: static int
1573: key_type_allowed_by_config(struct sshkey *key)
1574: {
1575: if (match_pattern_list(sshkey_ssh_name(key),
1576: options.pubkey_key_types, 0) == 1)
1577: return 1;
1578:
1579: /* RSA keys/certs might be allowed by alternate signature types */
1580: switch (key->type) {
1581: case KEY_RSA:
1582: if (match_pattern_list("rsa-sha2-512",
1583: options.pubkey_key_types, 0) == 1)
1584: return 1;
1585: if (match_pattern_list("rsa-sha2-256",
1586: options.pubkey_key_types, 0) == 1)
1587: return 1;
1588: break;
1589: case KEY_RSA_CERT:
1590: if (match_pattern_list("rsa-sha2-512-cert-v01@openssh.com",
1591: options.pubkey_key_types, 0) == 1)
1592: return 1;
1593: if (match_pattern_list("rsa-sha2-256-cert-v01@openssh.com",
1594: options.pubkey_key_types, 0) == 1)
1595: return 1;
1596: break;
1597: }
1598: return 0;
1599: }
1600:
1601:
1.117 markus 1602: /*
1603: * try keys in the following order:
1.227 djm 1604: * 1. certificates listed in the config file
1605: * 2. other input certificates
1606: * 3. agent keys that are found in the config file
1607: * 4. other agent keys
1608: * 5. keys that are only listed in the config file
1.117 markus 1609: */
1610: static void
1611: pubkey_prepare(Authctxt *authctxt)
1.51 markus 1612: {
1.214 djm 1613: struct identity *id, *id2, *tmp;
1614: struct idlist agent, files, *preferred;
1615: struct sshkey *key;
1.230 djm 1616: int agent_fd = -1, i, r, found;
1.214 djm 1617: size_t j;
1618: struct ssh_identitylist *idlist;
1.287 djm 1619: char *ident;
1.51 markus 1620:
1.117 markus 1621: TAILQ_INIT(&agent); /* keys from the agent */
1622: TAILQ_INIT(&files); /* keys from the config file */
1623: preferred = &authctxt->keys;
1624: TAILQ_INIT(preferred); /* preferred order of keys */
1625:
1.190 djm 1626: /* list of keys stored in the filesystem and PKCS#11 */
1.117 markus 1627: for (i = 0; i < options.num_identity_files; i++) {
1628: key = options.identity_keys[i];
1.309 djm 1629: if (key && key->cert &&
1630: key->cert->type != SSH2_CERT_TYPE_USER) {
1631: debug("%s: ignoring certificate %s: not a user "
1632: "certificate", __func__,
1633: options.identity_files[i]);
1634: continue;
1635: }
1.311 markus 1636: if (key && sshkey_is_sk(key) && options.sk_provider == NULL) {
1.319 naddy 1637: debug("%s: ignoring authenticator-hosted key %s as no "
1.309 djm 1638: "SecurityKeyProvider has been specified",
1639: __func__, options.identity_files[i]);
1.117 markus 1640: continue;
1.309 djm 1641: }
1.117 markus 1642: options.identity_keys[i] = NULL;
1.150 djm 1643: id = xcalloc(1, sizeof(*id));
1.230 djm 1644: id->agent_fd = -1;
1.117 markus 1645: id->key = key;
1646: id->filename = xstrdup(options.identity_files[i]);
1.192 dtucker 1647: id->userprovided = options.identity_file_userprovided[i];
1.117 markus 1648: TAILQ_INSERT_TAIL(&files, id, next);
1.190 djm 1649: }
1.227 djm 1650: /* list of certificates specified by user */
1651: for (i = 0; i < options.num_certificate_files; i++) {
1652: key = options.certificates[i];
1.278 markus 1653: if (!sshkey_is_cert(key) || key->cert == NULL ||
1.309 djm 1654: key->cert->type != SSH2_CERT_TYPE_USER) {
1655: debug("%s: ignoring certificate %s: not a user "
1656: "certificate", __func__,
1657: options.identity_files[i]);
1.227 djm 1658: continue;
1.309 djm 1659: }
1.311 markus 1660: if (key && sshkey_is_sk(key) && options.sk_provider == NULL) {
1.319 naddy 1661: debug("%s: ignoring authenticator-hosted key "
1662: "certificate %s as no "
1.309 djm 1663: "SecurityKeyProvider has been specified",
1664: __func__, options.identity_files[i]);
1665: continue;
1666: }
1.227 djm 1667: id = xcalloc(1, sizeof(*id));
1.230 djm 1668: id->agent_fd = -1;
1.227 djm 1669: id->key = key;
1670: id->filename = xstrdup(options.certificate_files[i]);
1671: id->userprovided = options.certificate_file_userprovided[i];
1672: TAILQ_INSERT_TAIL(preferred, id, next);
1.117 markus 1673: }
1674: /* list of keys supported by the agent */
1.214 djm 1675: if ((r = ssh_get_authentication_socket(&agent_fd)) != 0) {
1676: if (r != SSH_ERR_AGENT_NOT_PRESENT)
1677: debug("%s: ssh_get_authentication_socket: %s",
1678: __func__, ssh_err(r));
1.258 naddy 1679: } else if ((r = ssh_fetch_identitylist(agent_fd, &idlist)) != 0) {
1.214 djm 1680: if (r != SSH_ERR_AGENT_NO_IDENTITIES)
1681: debug("%s: ssh_fetch_identitylist: %s",
1682: __func__, ssh_err(r));
1.237 markus 1683: close(agent_fd);
1.214 djm 1684: } else {
1685: for (j = 0; j < idlist->nkeys; j++) {
1.117 markus 1686: found = 0;
1687: TAILQ_FOREACH(id, &files, next) {
1.214 djm 1688: /*
1689: * agent keys from the config file are
1690: * preferred
1691: */
1692: if (sshkey_equal(idlist->keys[j], id->key)) {
1.117 markus 1693: TAILQ_REMOVE(&files, id, next);
1694: TAILQ_INSERT_TAIL(preferred, id, next);
1.214 djm 1695: id->agent_fd = agent_fd;
1.117 markus 1696: found = 1;
1697: break;
1698: }
1699: }
1.135 markus 1700: if (!found && !options.identities_only) {
1.150 djm 1701: id = xcalloc(1, sizeof(*id));
1.214 djm 1702: /* XXX "steals" key/comment from idlist */
1703: id->key = idlist->keys[j];
1704: id->filename = idlist->comments[j];
1705: idlist->keys[j] = NULL;
1706: idlist->comments[j] = NULL;
1707: id->agent_fd = agent_fd;
1.117 markus 1708: TAILQ_INSERT_TAIL(&agent, id, next);
1709: }
1710: }
1.214 djm 1711: ssh_free_identitylist(idlist);
1.117 markus 1712: /* append remaining agent keys */
1.324 bket 1713: TAILQ_CONCAT(preferred, &agent, next);
1.214 djm 1714: authctxt->agent_fd = agent_fd;
1.244 djm 1715: }
1716: /* Prefer PKCS11 keys that are explicitly listed */
1717: TAILQ_FOREACH_SAFE(id, &files, next, tmp) {
1718: if (id->key == NULL || (id->key->flags & SSHKEY_FLAG_EXT) == 0)
1719: continue;
1720: found = 0;
1721: TAILQ_FOREACH(id2, &files, next) {
1722: if (id2->key == NULL ||
1.321 djm 1723: (id2->key->flags & SSHKEY_FLAG_EXT) != 0)
1.244 djm 1724: continue;
1725: if (sshkey_equal(id->key, id2->key)) {
1726: TAILQ_REMOVE(&files, id, next);
1727: TAILQ_INSERT_TAIL(preferred, id, next);
1728: found = 1;
1729: break;
1730: }
1731: }
1732: /* If IdentitiesOnly set and key not found then don't use it */
1733: if (!found && options.identities_only) {
1734: TAILQ_REMOVE(&files, id, next);
1.278 markus 1735: freezero(id, sizeof(*id));
1.244 djm 1736: }
1.117 markus 1737: }
1738: /* append remaining keys from the config file */
1.324 bket 1739: TAILQ_CONCAT(preferred, &files, next);
1.228 djm 1740: /* finally, filter by PubkeyAcceptedKeyTypes */
1741: TAILQ_FOREACH_SAFE(id, preferred, next, id2) {
1.273 djm 1742: if (id->key != NULL && !key_type_allowed_by_config(id->key)) {
1.228 djm 1743: debug("Skipping %s key %s - "
1744: "not in PubkeyAcceptedKeyTypes",
1745: sshkey_ssh_name(id->key), id->filename);
1746: TAILQ_REMOVE(preferred, id, next);
1747: sshkey_free(id->key);
1748: free(id->filename);
1749: memset(id, 0, sizeof(*id));
1750: continue;
1751: }
1.117 markus 1752: }
1.287 djm 1753: /* List the keys we plan on using */
1754: TAILQ_FOREACH_SAFE(id, preferred, next, id2) {
1755: ident = format_identity(id);
1756: debug("Will attempt key: %s", ident);
1757: free(ident);
1758: }
1759: debug2("%s: done", __func__);
1.17 markus 1760: }
1761:
1.117 markus 1762: static void
1.303 djm 1763: pubkey_cleanup(struct ssh *ssh)
1.51 markus 1764: {
1.302 djm 1765: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.117 markus 1766: Identity *id;
1.51 markus 1767:
1.289 djm 1768: if (authctxt->agent_fd != -1) {
1.214 djm 1769: ssh_close_authentication_socket(authctxt->agent_fd);
1.289 djm 1770: authctxt->agent_fd = -1;
1771: }
1.117 markus 1772: for (id = TAILQ_FIRST(&authctxt->keys); id;
1773: id = TAILQ_FIRST(&authctxt->keys)) {
1774: TAILQ_REMOVE(&authctxt->keys, id, next);
1.235 mmcc 1775: sshkey_free(id->key);
1.197 djm 1776: free(id->filename);
1777: free(id);
1.117 markus 1778: }
1.1 markus 1779: }
1780:
1.251 djm 1781: static void
1782: pubkey_reset(Authctxt *authctxt)
1783: {
1784: Identity *id;
1785:
1786: TAILQ_FOREACH(id, &authctxt->keys, next)
1787: id->tried = 0;
1788: }
1789:
1.225 markus 1790: static int
1791: try_identity(Identity *id)
1792: {
1793: if (!id->key)
1794: return (0);
1.279 markus 1795: if (sshkey_type_plain(id->key->type) == KEY_RSA &&
1.225 markus 1796: (datafellows & SSH_BUG_RSASIGMD5) != 0) {
1797: debug("Skipped %s key %s for RSA/MD5 server",
1.279 markus 1798: sshkey_type(id->key), id->filename);
1.225 markus 1799: return (0);
1800: }
1.257 djm 1801: return 1;
1.225 markus 1802: }
1803:
1.302 djm 1804: static int
1.295 djm 1805: userauth_pubkey(struct ssh *ssh)
1.20 markus 1806: {
1.295 djm 1807: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.117 markus 1808: Identity *id;
1.20 markus 1809: int sent = 0;
1.287 djm 1810: char *ident;
1.20 markus 1811:
1.117 markus 1812: while ((id = TAILQ_FIRST(&authctxt->keys))) {
1813: if (id->tried++)
1814: return (0);
1.127 markus 1815: /* move key to the end of the queue */
1.117 markus 1816: TAILQ_REMOVE(&authctxt->keys, id, next);
1817: TAILQ_INSERT_TAIL(&authctxt->keys, id, next);
1818: /*
1819: * send a test message if we have the public key. for
1820: * encrypted keys we cannot do this and have to load the
1821: * private key instead
1822: */
1.200 djm 1823: if (id->key != NULL) {
1.225 markus 1824: if (try_identity(id)) {
1.287 djm 1825: ident = format_identity(id);
1826: debug("Offering public key: %s", ident);
1827: free(ident);
1.295 djm 1828: sent = send_pubkey_test(ssh, id);
1.200 djm 1829: }
1830: } else {
1.117 markus 1831: debug("Trying private key: %s", id->filename);
1.229 jcs 1832: id->key = load_identity_file(id);
1.117 markus 1833: if (id->key != NULL) {
1.225 markus 1834: if (try_identity(id)) {
1835: id->isprivate = 1;
1.295 djm 1836: sent = sign_and_send_pubkey(ssh, id);
1.200 djm 1837: }
1.278 markus 1838: sshkey_free(id->key);
1.117 markus 1839: id->key = NULL;
1.251 djm 1840: id->isprivate = 0;
1.51 markus 1841: }
1842: }
1.117 markus 1843: if (sent)
1844: return (sent);
1.28 markus 1845: }
1.117 markus 1846: return (0);
1.20 markus 1847: }
1848:
1.23 markus 1849: /*
1850: * Send userauth request message specifying keyboard-interactive method.
1851: */
1.302 djm 1852: static int
1.295 djm 1853: userauth_kbdint(struct ssh *ssh)
1.23 markus 1854: {
1.295 djm 1855: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.278 markus 1856: int r;
1.23 markus 1857:
1.292 djm 1858: if (authctxt->attempt_kbdint++ >= options.number_of_password_prompts)
1.23 markus 1859: return 0;
1.82 markus 1860: /* disable if no SSH2_MSG_USERAUTH_INFO_REQUEST has been seen */
1.292 djm 1861: if (authctxt->attempt_kbdint > 1 && !authctxt->info_req_seen) {
1.82 markus 1862: debug3("userauth_kbdint: disable: no info_req_seen");
1.278 markus 1863: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_INFO_REQUEST, NULL);
1.82 markus 1864: return 0;
1865: }
1.23 markus 1866:
1867: debug2("userauth_kbdint");
1.278 markus 1868: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1869: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1870: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1871: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1872: (r = sshpkt_put_cstring(ssh, "")) != 0 || /* lang */
1873: (r = sshpkt_put_cstring(ssh, options.kbd_interactive_devices ?
1874: options.kbd_interactive_devices : "")) != 0 ||
1875: (r = sshpkt_send(ssh)) != 0)
1876: fatal("%s: %s", __func__, ssh_err(r));
1.23 markus 1877:
1.278 markus 1878: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_INFO_REQUEST, &input_userauth_info_req);
1.23 markus 1879: return 1;
1880: }
1881:
1882: /*
1.46 markus 1883: * parse INFO_REQUEST, prompt user and send INFO_RESPONSE
1.23 markus 1884: */
1.302 djm 1885: static int
1.261 markus 1886: input_userauth_info_req(int type, u_int32_t seq, struct ssh *ssh)
1.23 markus 1887: {
1.260 markus 1888: Authctxt *authctxt = ssh->authctxt;
1.278 markus 1889: char *name = NULL, *inst = NULL, *lang = NULL, *prompt = NULL;
1890: char *response = NULL;
1891: u_char echo = 0;
1.32 markus 1892: u_int num_prompts, i;
1.278 markus 1893: int r;
1.23 markus 1894:
1895: debug2("input_userauth_info_req");
1896:
1897: if (authctxt == NULL)
1898: fatal("input_userauth_info_req: no authentication context");
1.82 markus 1899:
1900: authctxt->info_req_seen = 1;
1.23 markus 1901:
1.278 markus 1902: if ((r = sshpkt_get_cstring(ssh, &name, NULL)) != 0 ||
1903: (r = sshpkt_get_cstring(ssh, &inst, NULL)) != 0 ||
1904: (r = sshpkt_get_cstring(ssh, &lang, NULL)) != 0)
1905: goto out;
1.23 markus 1906: if (strlen(name) > 0)
1.116 itojun 1907: logit("%s", name);
1.23 markus 1908: if (strlen(inst) > 0)
1.116 itojun 1909: logit("%s", inst);
1.23 markus 1910:
1.278 markus 1911: if ((r = sshpkt_get_u32(ssh, &num_prompts)) != 0)
1912: goto out;
1.23 markus 1913: /*
1914: * Begin to build info response packet based on prompts requested.
1915: * We commit to providing the correct number of responses, so if
1916: * further on we run into a problem that prevents this, we have to
1917: * be sure and clean this up and send a correct error response.
1918: */
1.278 markus 1919: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_INFO_RESPONSE)) != 0 ||
1920: (r = sshpkt_put_u32(ssh, num_prompts)) != 0)
1921: goto out;
1.23 markus 1922:
1.73 markus 1923: debug2("input_userauth_info_req: num_prompts %d", num_prompts);
1.23 markus 1924: for (i = 0; i < num_prompts; i++) {
1.278 markus 1925: if ((r = sshpkt_get_cstring(ssh, &prompt, NULL)) != 0 ||
1926: (r = sshpkt_get_u8(ssh, &echo)) != 0)
1927: goto out;
1.77 markus 1928: response = read_passphrase(prompt, echo ? RP_ECHO : 0);
1.278 markus 1929: if ((r = sshpkt_put_cstring(ssh, response)) != 0)
1930: goto out;
1931: freezero(response, strlen(response));
1.197 djm 1932: free(prompt);
1.278 markus 1933: response = prompt = NULL;
1.23 markus 1934: }
1.278 markus 1935: /* done with parsing incoming message. */
1936: if ((r = sshpkt_get_end(ssh)) != 0 ||
1937: (r = sshpkt_add_padding(ssh, 64)) != 0)
1938: goto out;
1939: r = sshpkt_send(ssh);
1940: out:
1941: if (response)
1942: freezero(response, strlen(response));
1943: free(prompt);
1944: free(name);
1945: free(inst);
1946: free(lang);
1947: return r;
1.68 markus 1948: }
1949:
1.100 markus 1950: static int
1.294 djm 1951: ssh_keysign(struct ssh *ssh, struct sshkey *key, u_char **sigp, size_t *lenp,
1.223 djm 1952: const u_char *data, size_t datalen)
1.100 markus 1953: {
1.223 djm 1954: struct sshbuf *b;
1.101 markus 1955: struct stat st;
1.100 markus 1956: pid_t pid;
1.304 deraadt 1957: int r, to[2], from[2], status;
1.295 djm 1958: int sock = ssh_packet_get_connection_in(ssh);
1.223 djm 1959: u_char rversion = 0, version = 2;
1960: void (*osigchld)(int);
1.100 markus 1961:
1.223 djm 1962: *sigp = NULL;
1963: *lenp = 0;
1.100 markus 1964:
1.306 deraadt 1965: if (stat(_PATH_SSH_KEY_SIGN, &st) == -1) {
1.223 djm 1966: error("%s: not installed: %s", __func__, strerror(errno));
1967: return -1;
1968: }
1969: if (fflush(stdout) != 0) {
1970: error("%s: fflush: %s", __func__, strerror(errno));
1.101 markus 1971: return -1;
1972: }
1.306 deraadt 1973: if (pipe(to) == -1) {
1.223 djm 1974: error("%s: pipe: %s", __func__, strerror(errno));
1.100 markus 1975: return -1;
1976: }
1.306 deraadt 1977: if (pipe(from) == -1) {
1.223 djm 1978: error("%s: pipe: %s", __func__, strerror(errno));
1.100 markus 1979: return -1;
1980: }
1.306 deraadt 1981: if ((pid = fork()) == -1) {
1.223 djm 1982: error("%s: fork: %s", __func__, strerror(errno));
1.100 markus 1983: return -1;
1984: }
1.317 dtucker 1985: osigchld = ssh_signal(SIGCHLD, SIG_DFL);
1.100 markus 1986: if (pid == 0) {
1987: close(from[0]);
1.306 deraadt 1988: if (dup2(from[1], STDOUT_FILENO) == -1)
1.223 djm 1989: fatal("%s: dup2: %s", __func__, strerror(errno));
1.100 markus 1990: close(to[1]);
1.306 deraadt 1991: if (dup2(to[0], STDIN_FILENO) == -1)
1.223 djm 1992: fatal("%s: dup2: %s", __func__, strerror(errno));
1.103 markus 1993: close(from[1]);
1994: close(to[0]);
1.304 deraadt 1995:
1.306 deraadt 1996: if (dup2(sock, STDERR_FILENO + 1) == -1)
1.304 deraadt 1997: fatal("%s: dup2: %s", __func__, strerror(errno));
1998: sock = STDERR_FILENO + 1;
1999: fcntl(sock, F_SETFD, 0); /* keep the socket on exec */
1.223 djm 2000: closefrom(sock + 1);
1.304 deraadt 2001:
1.223 djm 2002: debug3("%s: [child] pid=%ld, exec %s",
2003: __func__, (long)getpid(), _PATH_SSH_KEY_SIGN);
1.233 mmcc 2004: execl(_PATH_SSH_KEY_SIGN, _PATH_SSH_KEY_SIGN, (char *)NULL);
1.223 djm 2005: fatal("%s: exec(%s): %s", __func__, _PATH_SSH_KEY_SIGN,
1.100 markus 2006: strerror(errno));
2007: }
2008: close(from[1]);
2009: close(to[0]);
1.305 djm 2010: sock = STDERR_FILENO + 1;
1.100 markus 2011:
1.223 djm 2012: if ((b = sshbuf_new()) == NULL)
2013: fatal("%s: sshbuf_new failed", __func__);
2014: /* send # of sock, data to be signed */
1.253 djm 2015: if ((r = sshbuf_put_u32(b, sock)) != 0 ||
1.223 djm 2016: (r = sshbuf_put_string(b, data, datalen)) != 0)
2017: fatal("%s: buffer error: %s", __func__, ssh_err(r));
2018: if (ssh_msg_send(to[1], version, b) == -1)
2019: fatal("%s: couldn't send request", __func__);
2020: sshbuf_reset(b);
2021: r = ssh_msg_recv(from[0], b);
1.101 markus 2022: close(from[0]);
2023: close(to[1]);
1.223 djm 2024: if (r < 0) {
2025: error("%s: no reply", __func__);
2026: goto fail;
2027: }
1.101 markus 2028:
1.223 djm 2029: errno = 0;
1.306 deraadt 2030: while (waitpid(pid, &status, 0) == -1) {
1.223 djm 2031: if (errno != EINTR) {
2032: error("%s: waitpid %ld: %s",
2033: __func__, (long)pid, strerror(errno));
2034: goto fail;
2035: }
2036: }
2037: if (!WIFEXITED(status)) {
2038: error("%s: exited abnormally", __func__);
2039: goto fail;
2040: }
2041: if (WEXITSTATUS(status) != 0) {
2042: error("%s: exited with status %d",
2043: __func__, WEXITSTATUS(status));
2044: goto fail;
2045: }
2046: if ((r = sshbuf_get_u8(b, &rversion)) != 0) {
2047: error("%s: buffer error: %s", __func__, ssh_err(r));
2048: goto fail;
2049: }
2050: if (rversion != version) {
2051: error("%s: bad version", __func__);
2052: goto fail;
2053: }
2054: if ((r = sshbuf_get_string(b, sigp, lenp)) != 0) {
2055: error("%s: buffer error: %s", __func__, ssh_err(r));
2056: fail:
1.317 dtucker 2057: ssh_signal(SIGCHLD, osigchld);
1.223 djm 2058: sshbuf_free(b);
1.100 markus 2059: return -1;
2060: }
1.317 dtucker 2061: ssh_signal(SIGCHLD, osigchld);
1.223 djm 2062: sshbuf_free(b);
1.100 markus 2063:
2064: return 0;
2065: }
2066:
1.302 djm 2067: static int
1.295 djm 2068: userauth_hostbased(struct ssh *ssh)
1.68 markus 2069: {
1.295 djm 2070: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.223 djm 2071: struct sshkey *private = NULL;
2072: struct sshbuf *b = NULL;
2073: u_char *sig = NULL, *keyblob = NULL;
2074: char *fp = NULL, *chost = NULL, *lname = NULL;
2075: size_t siglen = 0, keylen = 0;
2076: int i, r, success = 0;
2077:
2078: if (authctxt->ktypes == NULL) {
2079: authctxt->oktypes = xstrdup(options.hostbased_key_types);
2080: authctxt->ktypes = authctxt->oktypes;
2081: }
1.213 djm 2082:
1.223 djm 2083: /*
2084: * Work through each listed type pattern in HostbasedKeyTypes,
2085: * trying each hostkey that matches the type in turn.
2086: */
2087: for (;;) {
2088: if (authctxt->active_ktype == NULL)
2089: authctxt->active_ktype = strsep(&authctxt->ktypes, ",");
2090: if (authctxt->active_ktype == NULL ||
2091: *authctxt->active_ktype == '\0')
2092: break;
2093: debug3("%s: trying key type %s", __func__,
2094: authctxt->active_ktype);
1.68 markus 2095:
1.223 djm 2096: /* check for a useful key */
2097: private = NULL;
2098: for (i = 0; i < authctxt->sensitive->nkeys; i++) {
2099: if (authctxt->sensitive->keys[i] == NULL ||
2100: authctxt->sensitive->keys[i]->type == KEY_UNSPEC)
2101: continue;
2102: if (match_pattern_list(
2103: sshkey_ssh_name(authctxt->sensitive->keys[i]),
1.224 djm 2104: authctxt->active_ktype, 0) != 1)
1.223 djm 2105: continue;
1.68 markus 2106: /* we take and free the key */
1.223 djm 2107: private = authctxt->sensitive->keys[i];
2108: authctxt->sensitive->keys[i] = NULL;
1.68 markus 2109: break;
2110: }
1.223 djm 2111: /* Found one */
2112: if (private != NULL)
2113: break;
2114: /* No more keys of this type; advance */
2115: authctxt->active_ktype = NULL;
1.68 markus 2116: }
1.223 djm 2117: if (private == NULL) {
2118: free(authctxt->oktypes);
2119: authctxt->oktypes = authctxt->ktypes = NULL;
2120: authctxt->active_ktype = NULL;
1.109 markus 2121: debug("No more client hostkeys for hostbased authentication.");
1.223 djm 2122: goto out;
1.68 markus 2123: }
1.211 djm 2124:
1.223 djm 2125: if ((fp = sshkey_fingerprint(private, options.fingerprint_hash,
2126: SSH_FP_DEFAULT)) == NULL) {
2127: error("%s: sshkey_fingerprint failed", __func__);
2128: goto out;
1.68 markus 2129: }
1.223 djm 2130: debug("%s: trying hostkey %s %s",
2131: __func__, sshkey_ssh_name(private), fp);
1.211 djm 2132:
1.84 markus 2133: /* figure out a name for the client host */
1.295 djm 2134: lname = get_local_name(ssh_packet_get_connection_in(ssh));
2135: if (lname == NULL) {
1.223 djm 2136: error("%s: cannot get local ipaddr/name", __func__);
2137: goto out;
1.84 markus 2138: }
1.223 djm 2139:
2140: /* XXX sshbuf_put_stringf? */
2141: xasprintf(&chost, "%s.", lname);
2142: debug2("%s: chost %s", __func__, chost);
1.84 markus 2143:
1.68 markus 2144: /* construct data */
1.223 djm 2145: if ((b = sshbuf_new()) == NULL) {
2146: error("%s: sshbuf_new failed", __func__);
2147: goto out;
2148: }
2149: if ((r = sshkey_to_blob(private, &keyblob, &keylen)) != 0) {
2150: error("%s: sshkey_to_blob: %s", __func__, ssh_err(r));
2151: goto out;
2152: }
2153: if ((r = sshbuf_put_string(b, session_id2, session_id2_len)) != 0 ||
2154: (r = sshbuf_put_u8(b, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
2155: (r = sshbuf_put_cstring(b, authctxt->server_user)) != 0 ||
1.267 djm 2156: (r = sshbuf_put_cstring(b, authctxt->service)) != 0 ||
1.223 djm 2157: (r = sshbuf_put_cstring(b, authctxt->method->name)) != 0 ||
1.279 markus 2158: (r = sshbuf_put_cstring(b, sshkey_ssh_name(private))) != 0 ||
1.223 djm 2159: (r = sshbuf_put_string(b, keyblob, keylen)) != 0 ||
2160: (r = sshbuf_put_cstring(b, chost)) != 0 ||
2161: (r = sshbuf_put_cstring(b, authctxt->local_user)) != 0) {
2162: error("%s: buffer error: %s", __func__, ssh_err(r));
2163: goto out;
2164: }
2165:
1.68 markus 2166: #ifdef DEBUG_PK
1.223 djm 2167: sshbuf_dump(b, stderr);
1.68 markus 2168: #endif
1.294 djm 2169: if ((r = ssh_keysign(ssh, private, &sig, &siglen,
2170: sshbuf_ptr(b), sshbuf_len(b))) != 0) {
1.223 djm 2171: error("sign using hostkey %s %s failed",
2172: sshkey_ssh_name(private), fp);
2173: goto out;
2174: }
2175: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
2176: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
2177: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
2178: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1.279 markus 2179: (r = sshpkt_put_cstring(ssh, sshkey_ssh_name(private))) != 0 ||
1.223 djm 2180: (r = sshpkt_put_string(ssh, keyblob, keylen)) != 0 ||
2181: (r = sshpkt_put_cstring(ssh, chost)) != 0 ||
2182: (r = sshpkt_put_cstring(ssh, authctxt->local_user)) != 0 ||
2183: (r = sshpkt_put_string(ssh, sig, siglen)) != 0 ||
2184: (r = sshpkt_send(ssh)) != 0) {
2185: error("%s: packet error: %s", __func__, ssh_err(r));
2186: goto out;
2187: }
2188: success = 1;
2189:
2190: out:
1.278 markus 2191: if (sig != NULL)
2192: freezero(sig, siglen);
1.223 djm 2193: free(keyblob);
2194: free(lname);
2195: free(fp);
1.197 djm 2196: free(chost);
1.223 djm 2197: sshkey_free(private);
2198: sshbuf_free(b);
1.68 markus 2199:
1.223 djm 2200: return success;
1.23 markus 2201: }
1.170 djm 2202:
1.20 markus 2203: /* find auth method */
2204:
2205: /*
2206: * given auth method name, if configurable options permit this method fill
2207: * in auth_ident field and return true, otherwise return false.
2208: */
1.76 itojun 2209: static int
1.20 markus 2210: authmethod_is_enabled(Authmethod *method)
2211: {
2212: if (method == NULL)
2213: return 0;
2214: /* return false if options indicate this method is disabled */
2215: if (method->enabled == NULL || *method->enabled == 0)
2216: return 0;
2217: /* return false if batch mode is enabled but method needs interactive mode */
2218: if (method->batch_flag != NULL && *method->batch_flag != 0)
2219: return 0;
2220: return 1;
2221: }
2222:
1.76 itojun 2223: static Authmethod *
1.20 markus 2224: authmethod_lookup(const char *name)
1.1 markus 2225: {
1.20 markus 2226: Authmethod *method = NULL;
2227: if (name != NULL)
2228: for (method = authmethods; method->name != NULL; method++)
2229: if (strcmp(name, method->name) == 0)
2230: return method;
2231: debug2("Unrecognized authentication method name: %s", name ? name : "NULL");
2232: return NULL;
2233: }
1.1 markus 2234:
1.53 markus 2235: /* XXX internal state */
2236: static Authmethod *current = NULL;
2237: static char *supported = NULL;
2238: static char *preferred = NULL;
1.105 deraadt 2239:
1.20 markus 2240: /*
2241: * Given the authentication method list sent by the server, return the
2242: * next method we should try. If the server initially sends a nil list,
1.67 markus 2243: * use a built-in default list.
1.41 stevesk 2244: */
1.76 itojun 2245: static Authmethod *
1.20 markus 2246: authmethod_get(char *authlist)
2247: {
1.53 markus 2248: char *name = NULL;
1.97 markus 2249: u_int next;
1.41 stevesk 2250:
1.20 markus 2251: /* Use a suitable default if we're passed a nil list. */
2252: if (authlist == NULL || strlen(authlist) == 0)
1.53 markus 2253: authlist = options.preferred_authentications;
1.20 markus 2254:
1.53 markus 2255: if (supported == NULL || strcmp(authlist, supported) != 0) {
2256: debug3("start over, passed a different list %s", authlist);
1.197 djm 2257: free(supported);
1.53 markus 2258: supported = xstrdup(authlist);
2259: preferred = options.preferred_authentications;
2260: debug3("preferred %s", preferred);
2261: current = NULL;
2262: } else if (current != NULL && authmethod_is_enabled(current))
2263: return current;
1.20 markus 2264:
1.53 markus 2265: for (;;) {
2266: if ((name = match_list(preferred, supported, &next)) == NULL) {
1.109 markus 2267: debug("No more authentication methods to try.");
1.53 markus 2268: current = NULL;
2269: return NULL;
2270: }
2271: preferred += next;
1.23 markus 2272: debug3("authmethod_lookup %s", name);
1.53 markus 2273: debug3("remaining preferred: %s", preferred);
2274: if ((current = authmethod_lookup(name)) != NULL &&
2275: authmethod_is_enabled(current)) {
1.23 markus 2276: debug3("authmethod_is_enabled %s", name);
1.109 markus 2277: debug("Next authentication method: %s", name);
1.197 djm 2278: free(name);
1.53 markus 2279: return current;
1.23 markus 2280: }
1.198 dtucker 2281: free(name);
1.1 markus 2282: }
1.53 markus 2283: }
1.1 markus 2284:
1.79 stevesk 2285: static char *
1.53 markus 2286: authmethods_get(void)
2287: {
2288: Authmethod *method = NULL;
1.278 markus 2289: struct sshbuf *b;
1.93 markus 2290: char *list;
1.278 markus 2291: int r;
1.27 provos 2292:
1.278 markus 2293: if ((b = sshbuf_new()) == NULL)
2294: fatal("%s: sshbuf_new failed", __func__);
1.53 markus 2295: for (method = authmethods; method->name != NULL; method++) {
2296: if (authmethod_is_enabled(method)) {
1.278 markus 2297: if ((r = sshbuf_putf(b, "%s%s",
2298: sshbuf_len(b) ? "," : "", method->name)) != 0)
2299: fatal("%s: buffer error: %s",
2300: __func__, ssh_err(r));
1.53 markus 2301: }
2302: }
1.278 markus 2303: if ((list = sshbuf_dup_string(b)) == NULL)
1.242 djm 2304: fatal("%s: sshbuf_dup_string failed", __func__);
1.278 markus 2305: sshbuf_free(b);
1.93 markus 2306: return list;
1.1 markus 2307: }
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