Annotation of src/usr.bin/ssh/sshconnect2.c, Revision 1.350
1.350 ! dtucker 1: /* $OpenBSD: sshconnect2.c,v 1.349 2021/06/07 03:38:38 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>
1.336 djm 35: #include <limits.h>
1.164 jolan 36: #include <netdb.h>
1.159 stevesk 37: #include <stdio.h>
1.158 stevesk 38: #include <string.h>
1.313 deraadt 39: #include <stdarg.h>
1.160 deraadt 40: #include <signal.h>
41: #include <pwd.h>
1.157 stevesk 42: #include <unistd.h>
1.166 djm 43: #include <vis.h>
1.1 markus 44:
1.160 deraadt 45: #include "xmalloc.h"
1.1 markus 46: #include "ssh.h"
1.37 markus 47: #include "ssh2.h"
1.278 markus 48: #include "sshbuf.h"
1.1 markus 49: #include "packet.h"
50: #include "compat.h"
1.37 markus 51: #include "cipher.h"
1.278 markus 52: #include "sshkey.h"
1.1 markus 53: #include "kex.h"
54: #include "myproposal.h"
55: #include "sshconnect.h"
56: #include "authfile.h"
1.57 provos 57: #include "dh.h"
1.17 markus 58: #include "authfd.h"
1.37 markus 59: #include "log.h"
1.210 millert 60: #include "misc.h"
1.37 markus 61: #include "readconf.h"
1.53 markus 62: #include "match.h"
1.61 markus 63: #include "dispatch.h"
1.68 markus 64: #include "canohost.h"
1.100 markus 65: #include "msg.h"
66: #include "pathnames.h"
1.154 markus 67: #include "uidswap.h"
1.186 djm 68: #include "hostfile.h"
1.214 djm 69: #include "ssherr.h"
1.246 djm 70: #include "utf8.h"
1.309 djm 71: #include "ssh-sk.h"
1.312 djm 72: #include "sk-api.h"
1.22 provos 73:
1.121 markus 74: #ifdef GSSAPI
75: #include "ssh-gss.h"
76: #endif
1.293 djm 77:
1.1 markus 78: /* import */
79: extern char *client_version_string;
80: extern char *server_version_string;
81: extern Options options;
82:
83: /*
84: * SSH2 key exchange
85: */
86:
1.338 djm 87: static char *xxx_host;
88: static struct sockaddr *xxx_hostaddr;
89: static const struct ssh_conn_info *xxx_conn_info;
1.61 markus 90:
1.76 itojun 91: static int
1.259 markus 92: verify_host_key_callback(struct sshkey *hostkey, struct ssh *ssh)
1.61 markus 93: {
1.338 djm 94: if (verify_host_key(xxx_host, xxx_hostaddr, hostkey,
95: xxx_conn_info) == -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 *
1.338 djm 113: order_hostkeyalgs(char *host, struct sockaddr *hostaddr, u_short port,
114: const struct ssh_conn_info *cinfo)
1.186 djm 115: {
1.326 djm 116: char *oavail = NULL, *avail = NULL, *first = NULL, *last = NULL;
117: char *alg = NULL, *hostname = NULL, *ret = NULL, *best = NULL;
1.186 djm 118: size_t maxlen;
1.326 djm 119: struct hostkeys *hostkeys = NULL;
1.186 djm 120: int ktype;
1.188 djm 121: u_int i;
1.186 djm 122:
123: /* Find all hostkeys for this hostname */
124: get_hostfile_hostname_ipaddr(host, hostaddr, port, &hostname, NULL);
125: hostkeys = init_hostkeys();
1.188 djm 126: for (i = 0; i < options.num_user_hostfiles; i++)
1.337 djm 127: load_hostkeys(hostkeys, hostname, options.user_hostfiles[i], 0);
128: for (i = 0; i < options.num_system_hostfiles; i++) {
129: load_hostkeys(hostkeys, hostname,
130: options.system_hostfiles[i], 0);
131: }
1.339 djm 132: if (options.known_hosts_command != NULL) {
133: load_hostkeys_command(hostkeys, options.known_hosts_command,
134: "ORDER", cinfo, NULL, host);
135: }
1.326 djm 136: /*
137: * If a plain public key exists that matches the type of the best
138: * preference HostkeyAlgorithms, then use the whole list as is.
139: * Note that we ignore whether the best preference algorithm is a
140: * certificate type, as sshconnect.c will downgrade certs to
141: * plain keys if necessary.
142: */
143: best = first_alg(options.hostkeyalgorithms);
144: if (lookup_key_in_hostkeys_by_type(hostkeys,
1.328 djm 145: sshkey_type_plain(sshkey_type_from_name(best)),
146: sshkey_ecdsa_nid_from_name(best), NULL)) {
1.331 djm 147: debug3_f("have matching best-preference key type %s, "
148: "using HostkeyAlgorithms verbatim", best);
1.326 djm 149: ret = xstrdup(options.hostkeyalgorithms);
150: goto out;
151: }
152:
153: /*
154: * Otherwise, prefer the host key algorithms that match known keys
155: * while keeping the ordering of HostkeyAlgorithms as much as possible.
156: */
1.320 djm 157: oavail = avail = xstrdup(options.hostkeyalgorithms);
1.186 djm 158: maxlen = strlen(avail) + 1;
159: first = xmalloc(maxlen);
160: last = xmalloc(maxlen);
161: *first = *last = '\0';
162:
163: #define ALG_APPEND(to, from) \
164: do { \
165: if (*to != '\0') \
166: strlcat(to, ",", maxlen); \
167: strlcat(to, from, maxlen); \
168: } while (0)
169:
170: while ((alg = strsep(&avail, ",")) && *alg != '\0') {
1.214 djm 171: if ((ktype = sshkey_type_from_name(alg)) == KEY_UNSPEC)
1.331 djm 172: fatal_f("unknown alg %s", alg);
1.322 djm 173: /*
174: * If we have a @cert-authority marker in known_hosts then
175: * prefer all certificate algorithms.
176: */
177: if (sshkey_type_is_cert(ktype) &&
178: lookup_marker_in_hostkeys(hostkeys, MRK_CA)) {
179: ALG_APPEND(first, alg);
180: continue;
181: }
182: /* If the key appears in known_hosts then prefer it */
1.186 djm 183: if (lookup_key_in_hostkeys_by_type(hostkeys,
1.328 djm 184: sshkey_type_plain(ktype),
185: sshkey_ecdsa_nid_from_name(alg), NULL)) {
1.186 djm 186: ALG_APPEND(first, alg);
1.322 djm 187: continue;
188: }
189: /* Otherwise, put it last */
190: ALG_APPEND(last, alg);
1.186 djm 191: }
192: #undef ALG_APPEND
1.216 djm 193: xasprintf(&ret, "%s%s%s", first,
194: (*first == '\0' || *last == '\0') ? "" : ",", last);
1.186 djm 195: if (*first != '\0')
1.331 djm 196: debug3_f("prefer hostkeyalgs: %s", first);
1.339 djm 197: else
198: debug3_f("no algorithms matched; accept original");
1.326 djm 199: out:
200: free(best);
1.197 djm 201: free(first);
202: free(last);
203: free(hostname);
204: free(oavail);
1.186 djm 205: free_hostkeys(hostkeys);
206:
207: return ret;
208: }
209:
1.1 markus 210: void
1.338 djm 211: ssh_kex2(struct ssh *ssh, char *host, struct sockaddr *hostaddr, u_short port,
212: const struct ssh_conn_info *cinfo)
1.22 provos 213: {
1.205 markus 214: char *myproposal[PROPOSAL_MAX] = { KEX_CLIENT };
1.275 djm 215: char *s, *all_key;
1.320 djm 216: int r, use_known_hosts_order = 0;
1.61 markus 217:
218: xxx_host = host;
219: xxx_hostaddr = hostaddr;
1.338 djm 220: xxx_conn_info = cinfo;
1.22 provos 221:
1.320 djm 222: /*
223: * If the user has not specified HostkeyAlgorithms, or has only
224: * appended or removed algorithms from that list then prefer algorithms
225: * that are in the list that are supported by known_hosts keys.
226: */
227: if (options.hostkeyalgorithms == NULL ||
228: options.hostkeyalgorithms[0] == '-' ||
229: options.hostkeyalgorithms[0] == '+')
230: use_known_hosts_order = 1;
231:
232: /* Expand or fill in HostkeyAlgorithms */
233: all_key = sshkey_alg_list(0, 0, 1, ',');
1.333 djm 234: if ((r = kex_assemble_names(&options.hostkeyalgorithms,
235: kex_default_pk_alg(), all_key)) != 0)
236: fatal_fr(r, "kex_assemble_namelist");
1.320 djm 237: free(all_key);
238:
1.231 markus 239: if ((s = kex_names_cat(options.kex_algorithms, "ext-info-c")) == NULL)
1.331 djm 240: fatal_f("kex_names_cat");
1.345 djm 241: myproposal[PROPOSAL_KEX_ALGS] = compat_kex_proposal(ssh, s);
1.60 stevesk 242: myproposal[PROPOSAL_ENC_ALGS_CTOS] =
1.345 djm 243: compat_cipher_proposal(ssh, options.ciphers);
1.60 stevesk 244: myproposal[PROPOSAL_ENC_ALGS_STOC] =
1.345 djm 245: compat_cipher_proposal(ssh, options.ciphers);
1.245 dtucker 246: myproposal[PROPOSAL_COMP_ALGS_CTOS] =
1.318 dtucker 247: myproposal[PROPOSAL_COMP_ALGS_STOC] =
248: (char *)compression_alg_list(options.compression);
1.226 djm 249: myproposal[PROPOSAL_MAC_ALGS_CTOS] =
250: myproposal[PROPOSAL_MAC_ALGS_STOC] = options.macs;
1.320 djm 251: if (use_known_hosts_order) {
252: /* Query known_hosts and prefer algorithms that appear there */
1.88 deraadt 253: myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] =
1.345 djm 254: compat_pkalg_proposal(ssh,
1.338 djm 255: order_hostkeyalgs(host, hostaddr, port, cinfo));
1.226 djm 256: } else {
1.320 djm 257: /* Use specified HostkeyAlgorithms exactly */
1.186 djm 258: myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] =
1.345 djm 259: compat_pkalg_proposal(ssh, options.hostkeyalgorithms);
1.186 djm 260: }
1.115 markus 261:
1.196 dtucker 262: if (options.rekey_limit || options.rekey_interval)
1.294 djm 263: ssh_packet_set_rekey_limits(ssh, options.rekey_limit,
1.254 dtucker 264: options.rekey_interval);
1.22 provos 265:
1.65 markus 266: /* start key exchange */
1.291 djm 267: if ((r = kex_setup(ssh, myproposal)) != 0)
1.331 djm 268: fatal_r(r, "kex_setup");
1.207 markus 269: #ifdef WITH_OPENSSL
1.301 djm 270: ssh->kex->kex[KEX_DH_GRP1_SHA1] = kex_gen_client;
271: ssh->kex->kex[KEX_DH_GRP14_SHA1] = kex_gen_client;
272: ssh->kex->kex[KEX_DH_GRP14_SHA256] = kex_gen_client;
273: ssh->kex->kex[KEX_DH_GRP16_SHA512] = kex_gen_client;
274: ssh->kex->kex[KEX_DH_GRP18_SHA512] = kex_gen_client;
1.291 djm 275: ssh->kex->kex[KEX_DH_GEX_SHA1] = kexgex_client;
276: ssh->kex->kex[KEX_DH_GEX_SHA256] = kexgex_client;
1.301 djm 277: ssh->kex->kex[KEX_ECDH_SHA2] = kex_gen_client;
1.207 markus 278: #endif
1.301 djm 279: ssh->kex->kex[KEX_C25519_SHA256] = kex_gen_client;
1.340 djm 280: ssh->kex->kex[KEX_KEM_SNTRUP761X25519_SHA512] = kex_gen_client;
1.291 djm 281: ssh->kex->verify_host_key=&verify_host_key_callback;
1.22 provos 282:
1.291 djm 283: ssh_dispatch_run_fatal(ssh, DISPATCH_BLOCK, &ssh->kex->done);
1.173 andreas 284:
1.231 markus 285: /* remove ext-info from the KEX proposals for rekeying */
286: myproposal[PROPOSAL_KEX_ALGS] =
1.345 djm 287: compat_kex_proposal(ssh, options.kex_algorithms);
1.291 djm 288: if ((r = kex_prop2buf(ssh->kex->my, myproposal)) != 0)
1.331 djm 289: fatal_r(r, "kex_prop2buf");
1.62 markus 290:
1.22 provos 291: #ifdef DEBUG_KEXDH
292: /* send 1st encrypted/maced/compressed message */
1.278 markus 293: if ((r = sshpkt_start(ssh, SSH2_MSG_IGNORE)) != 0 ||
294: (r = sshpkt_put_cstring(ssh, "markus")) != 0 ||
1.280 markus 295: (r = sshpkt_send(ssh)) != 0 ||
296: (r = ssh_packet_write_wait(ssh)) != 0)
1.331 djm 297: fatal_fr(r, "send packet");
1.22 provos 298: #endif
1.1 markus 299: }
1.11 markus 300:
1.1 markus 301: /*
302: * Authenticate user
303: */
1.20 markus 304:
1.214 djm 305: typedef struct cauthctxt Authctxt;
306: typedef struct cauthmethod Authmethod;
1.117 markus 307: typedef struct identity Identity;
308: typedef struct idlist Idlist;
1.20 markus 309:
1.117 markus 310: struct identity {
311: TAILQ_ENTRY(identity) next;
1.214 djm 312: int agent_fd; /* >=0 if agent supports key */
313: struct sshkey *key; /* public/private key */
1.117 markus 314: char *filename; /* comment for agent-only keys */
315: int tried;
316: int isprivate; /* key points to the private key */
1.191 dtucker 317: int userprovided;
1.117 markus 318: };
319: TAILQ_HEAD(idlist, identity);
1.20 markus 320:
1.214 djm 321: struct cauthctxt {
1.20 markus 322: const char *server_user;
1.68 markus 323: const char *local_user;
1.20 markus 324: const char *host;
325: const char *service;
1.214 djm 326: struct cauthmethod *method;
1.183 djm 327: sig_atomic_t success;
1.51 markus 328: char *authlist;
1.302 djm 329: #ifdef GSSAPI
330: /* gssapi */
331: gss_OID_set gss_supported_mechs;
332: u_int mech_tried;
333: #endif
1.68 markus 334: /* pubkey */
1.214 djm 335: struct idlist keys;
336: int agent_fd;
1.68 markus 337: /* hostbased */
1.100 markus 338: Sensitive *sensitive;
1.223 djm 339: char *oktypes, *ktypes;
340: const char *active_ktype;
1.82 markus 341: /* kbd-interactive */
342: int info_req_seen;
1.292 djm 343: int attempt_kbdint;
344: /* password */
345: int attempt_passwd;
1.121 markus 346: /* generic */
347: void *methoddata;
1.20 markus 348: };
1.214 djm 349:
350: struct cauthmethod {
1.20 markus 351: char *name; /* string to compare against server's list */
1.295 djm 352: int (*userauth)(struct ssh *ssh);
353: void (*cleanup)(struct ssh *ssh);
1.20 markus 354: int *enabled; /* flag in option struct that enables method */
355: int *batch_flag; /* flag in option struct that disables method */
356: };
357:
1.302 djm 358: static int input_userauth_service_accept(int, u_int32_t, struct ssh *);
359: static int input_userauth_ext_info(int, u_int32_t, struct ssh *);
360: static int input_userauth_success(int, u_int32_t, struct ssh *);
361: static int input_userauth_failure(int, u_int32_t, struct ssh *);
362: static int input_userauth_banner(int, u_int32_t, struct ssh *);
363: static int input_userauth_error(int, u_int32_t, struct ssh *);
364: static int input_userauth_info_req(int, u_int32_t, struct ssh *);
365: static int input_userauth_pk_ok(int, u_int32_t, struct ssh *);
366: static int input_userauth_passwd_changereq(int, u_int32_t, struct ssh *);
367:
368: static int userauth_none(struct ssh *);
369: static int userauth_pubkey(struct ssh *);
370: static int userauth_passwd(struct ssh *);
371: static int userauth_kbdint(struct ssh *);
372: static int userauth_hostbased(struct ssh *);
1.20 markus 373:
1.121 markus 374: #ifdef GSSAPI
1.302 djm 375: static int userauth_gssapi(struct ssh *);
376: static void userauth_gssapi_cleanup(struct ssh *);
377: static int input_gssapi_response(int type, u_int32_t, struct ssh *);
378: static int input_gssapi_token(int type, u_int32_t, struct ssh *);
379: static int input_gssapi_error(int, u_int32_t, struct ssh *);
380: static int input_gssapi_errtok(int, u_int32_t, struct ssh *);
1.121 markus 381: #endif
382:
1.295 djm 383: void userauth(struct ssh *, char *);
1.51 markus 384:
1.303 djm 385: static void pubkey_cleanup(struct ssh *);
1.295 djm 386: static int sign_and_send_pubkey(struct ssh *ssh, Identity *);
1.117 markus 387: static void pubkey_prepare(Authctxt *);
1.251 djm 388: static void pubkey_reset(Authctxt *);
1.259 markus 389: static struct sshkey *load_identity_file(Identity *);
1.76 itojun 390:
391: static Authmethod *authmethod_get(char *authlist);
392: static Authmethod *authmethod_lookup(const char *name);
393: static char *authmethods_get(void);
1.20 markus 394:
395: Authmethod authmethods[] = {
1.121 markus 396: #ifdef GSSAPI
1.132 markus 397: {"gssapi-with-mic",
1.121 markus 398: userauth_gssapi,
1.302 djm 399: userauth_gssapi_cleanup,
1.121 markus 400: &options.gss_authentication,
401: NULL},
402: #endif
1.81 markus 403: {"hostbased",
404: userauth_hostbased,
1.170 djm 405: NULL,
1.81 markus 406: &options.hostbased_authentication,
407: NULL},
1.20 markus 408: {"publickey",
409: userauth_pubkey,
1.303 djm 410: NULL,
1.28 markus 411: &options.pubkey_authentication,
1.20 markus 412: NULL},
1.81 markus 413: {"keyboard-interactive",
414: userauth_kbdint,
1.170 djm 415: NULL,
1.81 markus 416: &options.kbd_interactive_authentication,
417: &options.batch_mode},
1.20 markus 418: {"password",
419: userauth_passwd,
1.170 djm 420: NULL,
1.20 markus 421: &options.password_authentication,
1.23 markus 422: &options.batch_mode},
423: {"none",
424: userauth_none,
425: NULL,
1.170 djm 426: NULL,
1.23 markus 427: NULL},
1.170 djm 428: {NULL, NULL, NULL, NULL, NULL}
1.20 markus 429: };
430:
431: void
1.291 djm 432: ssh_userauth2(struct ssh *ssh, const char *local_user,
433: const char *server_user, char *host, Sensitive *sensitive)
1.20 markus 434: {
435: Authctxt authctxt;
1.231 markus 436: int r;
1.39 markus 437:
1.53 markus 438: if (options.preferred_authentications == NULL)
439: options.preferred_authentications = authmethods_get();
440:
1.20 markus 441: /* setup authentication context */
1.82 markus 442: memset(&authctxt, 0, sizeof(authctxt));
1.20 markus 443: authctxt.server_user = server_user;
1.68 markus 444: authctxt.local_user = local_user;
1.20 markus 445: authctxt.host = host;
446: authctxt.service = "ssh-connection"; /* service name */
447: authctxt.success = 0;
1.23 markus 448: authctxt.method = authmethod_lookup("none");
1.51 markus 449: authctxt.authlist = NULL;
1.121 markus 450: authctxt.methoddata = NULL;
1.100 markus 451: authctxt.sensitive = sensitive;
1.223 djm 452: authctxt.active_ktype = authctxt.oktypes = authctxt.ktypes = NULL;
1.82 markus 453: authctxt.info_req_seen = 0;
1.292 djm 454: authctxt.attempt_kbdint = 0;
455: authctxt.attempt_passwd = 0;
1.302 djm 456: #if GSSAPI
457: authctxt.gss_supported_mechs = NULL;
458: authctxt.mech_tried = 0;
459: #endif
1.215 djm 460: authctxt.agent_fd = -1;
1.289 djm 461: pubkey_prepare(&authctxt);
1.291 djm 462: if (authctxt.method == NULL) {
1.331 djm 463: fatal_f("internal error: cannot send userauth none request");
1.291 djm 464: }
1.20 markus 465:
1.231 markus 466: if ((r = sshpkt_start(ssh, SSH2_MSG_SERVICE_REQUEST)) != 0 ||
467: (r = sshpkt_put_cstring(ssh, "ssh-userauth")) != 0 ||
468: (r = sshpkt_send(ssh)) != 0)
1.331 djm 469: fatal_fr(r, "send packet");
1.231 markus 470:
1.260 markus 471: ssh->authctxt = &authctxt;
1.231 markus 472: ssh_dispatch_init(ssh, &input_userauth_error);
473: ssh_dispatch_set(ssh, SSH2_MSG_EXT_INFO, &input_userauth_ext_info);
474: ssh_dispatch_set(ssh, SSH2_MSG_SERVICE_ACCEPT, &input_userauth_service_accept);
1.263 markus 475: ssh_dispatch_run_fatal(ssh, DISPATCH_BLOCK, &authctxt.success); /* loop until success */
1.303 djm 476: pubkey_cleanup(ssh);
1.260 markus 477: ssh->authctxt = NULL;
1.20 markus 478:
1.231 markus 479: ssh_dispatch_range(ssh, SSH2_MSG_USERAUTH_MIN, SSH2_MSG_USERAUTH_MAX, NULL);
1.119 markus 480:
1.248 dtucker 481: if (!authctxt.success)
482: fatal("Authentication failed.");
1.109 markus 483: debug("Authentication succeeded (%s).", authctxt.method->name);
1.20 markus 484: }
1.119 markus 485:
1.231 markus 486: /* ARGSUSED */
1.302 djm 487: static int
1.261 markus 488: input_userauth_service_accept(int type, u_int32_t seq, struct ssh *ssh)
1.231 markus 489: {
490: int r;
491:
492: if (ssh_packet_remaining(ssh) > 0) {
493: char *reply;
494:
495: if ((r = sshpkt_get_cstring(ssh, &reply, NULL)) != 0)
496: goto out;
497: debug2("service_accept: %s", reply);
498: free(reply);
499: } else {
500: debug2("buggy server: service_accept w/o service");
501: }
502: if ((r = sshpkt_get_end(ssh)) != 0)
503: goto out;
504: debug("SSH2_MSG_SERVICE_ACCEPT received");
505:
506: /* initial userauth request */
1.295 djm 507: userauth_none(ssh);
1.231 markus 508:
509: ssh_dispatch_set(ssh, SSH2_MSG_EXT_INFO, &input_userauth_error);
510: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_SUCCESS, &input_userauth_success);
511: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_FAILURE, &input_userauth_failure);
512: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_BANNER, &input_userauth_banner);
513: r = 0;
514: out:
515: return r;
516: }
517:
518: /* ARGSUSED */
1.302 djm 519: static int
1.261 markus 520: input_userauth_ext_info(int type, u_int32_t seqnr, struct ssh *ssh)
1.231 markus 521: {
1.261 markus 522: return kex_input_ext_info(type, seqnr, ssh);
1.231 markus 523: }
524:
1.20 markus 525: void
1.295 djm 526: userauth(struct ssh *ssh, char *authlist)
1.51 markus 527: {
1.295 djm 528: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.278 markus 529:
1.170 djm 530: if (authctxt->method != NULL && authctxt->method->cleanup != NULL)
1.295 djm 531: authctxt->method->cleanup(ssh);
1.170 djm 532:
1.197 djm 533: free(authctxt->methoddata);
534: authctxt->methoddata = NULL;
1.51 markus 535: if (authlist == NULL) {
536: authlist = authctxt->authlist;
537: } else {
1.197 djm 538: free(authctxt->authlist);
1.51 markus 539: authctxt->authlist = authlist;
540: }
541: for (;;) {
542: Authmethod *method = authmethod_get(authlist);
543: if (method == NULL)
1.264 dtucker 544: fatal("%s@%s: Permission denied (%s).",
545: authctxt->server_user, authctxt->host, authlist);
1.51 markus 546: authctxt->method = method;
1.119 markus 547:
548: /* reset the per method handler */
1.278 markus 549: ssh_dispatch_range(ssh, SSH2_MSG_USERAUTH_PER_METHOD_MIN,
1.119 markus 550: SSH2_MSG_USERAUTH_PER_METHOD_MAX, NULL);
551:
552: /* and try new method */
1.295 djm 553: if (method->userauth(ssh) != 0) {
1.51 markus 554: debug2("we sent a %s packet, wait for reply", method->name);
555: break;
556: } else {
557: debug2("we did not send a packet, disable method");
558: method->enabled = NULL;
559: }
560: }
561: }
1.105 deraadt 562:
1.169 djm 563: /* ARGSUSED */
1.302 djm 564: static int
1.261 markus 565: input_userauth_error(int type, u_int32_t seq, struct ssh *ssh)
1.20 markus 566: {
1.331 djm 567: fatal_f("bad message during authentication: type %d", type);
1.218 markus 568: return 0;
1.35 markus 569: }
1.105 deraadt 570:
1.169 djm 571: /* ARGSUSED */
1.302 djm 572: static int
1.261 markus 573: input_userauth_banner(int type, u_int32_t seq, struct ssh *ssh)
1.35 markus 574: {
1.295 djm 575: char *msg = NULL;
1.294 djm 576: size_t len;
577: int r;
1.126 deraadt 578:
1.331 djm 579: debug3_f("entering");
1.294 djm 580: if ((r = sshpkt_get_cstring(ssh, &msg, &len)) != 0 ||
1.295 djm 581: (r = sshpkt_get_cstring(ssh, NULL, NULL)) != 0)
1.294 djm 582: goto out;
1.246 djm 583: if (len > 0 && options.log_level >= SYSLOG_LEVEL_INFO)
584: fmprintf(stderr, "%s", msg);
1.294 djm 585: r = 0;
586: out:
1.246 djm 587: free(msg);
1.294 djm 588: return r;
1.20 markus 589: }
1.105 deraadt 590:
1.169 djm 591: /* ARGSUSED */
1.302 djm 592: static int
1.261 markus 593: input_userauth_success(int type, u_int32_t seq, struct ssh *ssh)
1.20 markus 594: {
1.260 markus 595: Authctxt *authctxt = ssh->authctxt;
1.172 djm 596:
1.20 markus 597: if (authctxt == NULL)
1.331 djm 598: fatal_f("no authentication context");
1.197 djm 599: free(authctxt->authlist);
600: authctxt->authlist = NULL;
1.172 djm 601: if (authctxt->method != NULL && authctxt->method->cleanup != NULL)
1.295 djm 602: authctxt->method->cleanup(ssh);
1.197 djm 603: free(authctxt->methoddata);
604: authctxt->methoddata = NULL;
1.20 markus 605: authctxt->success = 1; /* break out */
1.218 markus 606: return 0;
1.20 markus 607: }
1.105 deraadt 608:
1.302 djm 609: #if 0
610: static int
1.261 markus 611: input_userauth_success_unexpected(int type, u_int32_t seq, struct ssh *ssh)
1.172 djm 612: {
1.260 markus 613: Authctxt *authctxt = ssh->authctxt;
1.172 djm 614:
615: if (authctxt == NULL)
1.331 djm 616: fatal_f("no authentication context");
1.172 djm 617:
618: fatal("Unexpected authentication success during %s.",
619: authctxt->method->name);
1.218 markus 620: return 0;
1.172 djm 621: }
1.302 djm 622: #endif
1.172 djm 623:
1.169 djm 624: /* ARGSUSED */
1.302 djm 625: static int
1.261 markus 626: input_userauth_failure(int type, u_int32_t seq, struct ssh *ssh)
1.20 markus 627: {
1.260 markus 628: Authctxt *authctxt = ssh->authctxt;
1.20 markus 629: char *authlist = NULL;
1.278 markus 630: u_char partial;
1.20 markus 631:
632: if (authctxt == NULL)
633: fatal("input_userauth_failure: no authentication context");
634:
1.307 dtucker 635: if (sshpkt_get_cstring(ssh, &authlist, NULL) != 0 ||
636: sshpkt_get_u8(ssh, &partial) != 0 ||
637: sshpkt_get_end(ssh) != 0)
1.278 markus 638: goto out;
1.20 markus 639:
1.193 markus 640: if (partial != 0) {
1.247 dtucker 641: verbose("Authenticated with partial success.");
1.193 markus 642: /* reset state */
1.251 djm 643: pubkey_reset(authctxt);
1.193 markus 644: }
1.109 markus 645: debug("Authentications that can continue: %s", authlist);
1.20 markus 646:
1.295 djm 647: userauth(ssh, authlist);
1.278 markus 648: authlist = NULL;
649: out:
650: free(authlist);
1.218 markus 651: return 0;
1.51 markus 652: }
1.169 djm 653:
1.287 djm 654: /*
655: * Format an identity for logging including filename, key type, fingerprint
656: * and location (agent, etc.). Caller must free.
657: */
658: static char *
659: format_identity(Identity *id)
660: {
661: char *fp = NULL, *ret = NULL;
1.309 djm 662: const char *note = "";
1.287 djm 663:
664: if (id->key != NULL) {
1.347 djm 665: fp = sshkey_fingerprint(id->key, options.fingerprint_hash,
1.287 djm 666: SSH_FP_DEFAULT);
667: }
1.309 djm 668: if (id->key) {
669: if ((id->key->flags & SSHKEY_FLAG_EXT) != 0)
670: note = " token";
1.311 markus 671: else if (sshkey_is_sk(id->key))
1.319 naddy 672: note = " authenticator";
1.309 djm 673: }
1.287 djm 674: xasprintf(&ret, "%s %s%s%s%s%s%s",
675: id->filename,
676: id->key ? sshkey_type(id->key) : "", id->key ? " " : "",
677: fp ? fp : "",
1.309 djm 678: id->userprovided ? " explicit" : "", note,
1.287 djm 679: id->agent_fd != -1 ? " agent" : "");
680: free(fp);
681: return ret;
682: }
683:
1.169 djm 684: /* ARGSUSED */
1.302 djm 685: static int
1.261 markus 686: input_userauth_pk_ok(int type, u_int32_t seq, struct ssh *ssh)
1.51 markus 687: {
1.260 markus 688: Authctxt *authctxt = ssh->authctxt;
1.259 markus 689: struct sshkey *key = NULL;
1.117 markus 690: Identity *id = NULL;
1.287 djm 691: int pktype, found = 0, sent = 0;
1.278 markus 692: size_t blen;
1.287 djm 693: char *pkalg = NULL, *fp = NULL, *ident = NULL;
1.278 markus 694: u_char *pkblob = NULL;
695: int r;
1.51 markus 696:
697: if (authctxt == NULL)
698: fatal("input_userauth_pk_ok: no authentication context");
1.267 djm 699:
1.278 markus 700: if ((r = sshpkt_get_cstring(ssh, &pkalg, NULL)) != 0 ||
701: (r = sshpkt_get_string(ssh, &pkblob, &blen)) != 0 ||
702: (r = sshpkt_get_end(ssh)) != 0)
703: goto done;
1.51 markus 704:
1.278 markus 705: if ((pktype = sshkey_type_from_name(pkalg)) == KEY_UNSPEC) {
1.331 djm 706: debug_f("server sent unknown pkalg %s", pkalg);
1.117 markus 707: goto done;
708: }
1.278 markus 709: if ((r = sshkey_from_blob(pkblob, blen, &key)) != 0) {
1.331 djm 710: debug_r(r, "no key from blob. pkalg %s", pkalg);
1.117 markus 711: goto done;
712: }
713: if (key->type != pktype) {
714: error("input_userauth_pk_ok: type mismatch "
715: "for decoded key (received %d, expected %d)",
716: key->type, pktype);
717: goto done;
718: }
719:
1.127 markus 720: /*
721: * search keys in the reverse order, because last candidate has been
722: * moved to the end of the queue. this also avoids confusion by
723: * duplicate keys
724: */
1.136 henning 725: TAILQ_FOREACH_REVERSE(id, &authctxt->keys, idlist, next) {
1.278 markus 726: if (sshkey_equal(key, id->key)) {
1.287 djm 727: found = 1;
1.51 markus 728: break;
729: }
1.117 markus 730: }
1.287 djm 731: if (!found || id == NULL) {
732: fp = sshkey_fingerprint(key, options.fingerprint_hash,
733: SSH_FP_DEFAULT);
1.331 djm 734: error_f("server replied with unknown key: %s %s",
1.287 djm 735: sshkey_type(key), fp == NULL ? "<ERROR>" : fp);
736: goto done;
737: }
738: ident = format_identity(id);
739: debug("Server accepts key: %s", ident);
1.295 djm 740: sent = sign_and_send_pubkey(ssh, id);
1.278 markus 741: r = 0;
742: done:
743: sshkey_free(key);
1.287 djm 744: free(ident);
745: free(fp);
1.197 djm 746: free(pkalg);
747: free(pkblob);
1.51 markus 748:
1.106 deraadt 749: /* try another method if we did not send a packet */
1.278 markus 750: if (r == 0 && sent == 0)
1.295 djm 751: userauth(ssh, NULL);
1.278 markus 752: return r;
1.20 markus 753: }
1.121 markus 754:
755: #ifdef GSSAPI
1.302 djm 756: static int
1.295 djm 757: userauth_gssapi(struct ssh *ssh)
1.121 markus 758: {
1.295 djm 759: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.121 markus 760: Gssctxt *gssctxt = NULL;
761: OM_uint32 min;
1.278 markus 762: int r, ok = 0;
1.302 djm 763: gss_OID mech = NULL;
1.121 markus 764:
765: /* Try one GSSAPI method at a time, rather than sending them all at
766: * once. */
767:
1.302 djm 768: if (authctxt->gss_supported_mechs == NULL)
769: gss_indicate_mechs(&min, &authctxt->gss_supported_mechs);
1.121 markus 770:
1.302 djm 771: /* Check to see whether the mechanism is usable before we offer it */
772: while (authctxt->mech_tried < authctxt->gss_supported_mechs->count &&
773: !ok) {
774: mech = &authctxt->gss_supported_mechs->
775: elements[authctxt->mech_tried];
1.121 markus 776: /* My DER encoding requires length<128 */
1.302 djm 777: if (mech->length < 128 && ssh_gssapi_check_mechanism(&gssctxt,
778: mech, authctxt->host)) {
1.121 markus 779: ok = 1; /* Mechanism works */
780: } else {
1.302 djm 781: authctxt->mech_tried++;
1.121 markus 782: }
783: }
784:
1.302 djm 785: if (!ok || mech == NULL)
1.139 djm 786: return 0;
1.121 markus 787:
788: authctxt->methoddata=(void *)gssctxt;
789:
1.278 markus 790: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
791: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
792: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
793: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
794: (r = sshpkt_put_u32(ssh, 1)) != 0 ||
1.302 djm 795: (r = sshpkt_put_u32(ssh, (mech->length) + 2)) != 0 ||
1.278 markus 796: (r = sshpkt_put_u8(ssh, SSH_GSS_OIDTYPE)) != 0 ||
1.302 djm 797: (r = sshpkt_put_u8(ssh, mech->length)) != 0 ||
798: (r = sshpkt_put(ssh, mech->elements, mech->length)) != 0 ||
1.278 markus 799: (r = sshpkt_send(ssh)) != 0)
1.331 djm 800: fatal_fr(r, "send packet");
1.278 markus 801:
802: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_RESPONSE, &input_gssapi_response);
803: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_TOKEN, &input_gssapi_token);
804: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_ERROR, &input_gssapi_error);
805: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_ERRTOK, &input_gssapi_errtok);
1.121 markus 806:
1.302 djm 807: authctxt->mech_tried++; /* Move along to next candidate */
1.121 markus 808:
809: return 1;
810: }
811:
1.302 djm 812: static void
813: userauth_gssapi_cleanup(struct ssh *ssh)
814: {
815: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
816: Gssctxt *gssctxt = (Gssctxt *)authctxt->methoddata;
817:
818: ssh_gssapi_delete_ctx(&gssctxt);
819: authctxt->methoddata = NULL;
820:
821: free(authctxt->gss_supported_mechs);
822: authctxt->gss_supported_mechs = NULL;
823: }
824:
1.130 markus 825: static OM_uint32
1.262 djm 826: process_gssapi_token(struct ssh *ssh, gss_buffer_t recv_tok)
1.130 markus 827: {
1.260 markus 828: Authctxt *authctxt = ssh->authctxt;
1.130 markus 829: Gssctxt *gssctxt = authctxt->methoddata;
830: gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
1.142 djm 831: gss_buffer_desc mic = GSS_C_EMPTY_BUFFER;
832: gss_buffer_desc gssbuf;
1.132 markus 833: OM_uint32 status, ms, flags;
1.278 markus 834: int r;
1.133 djm 835:
1.130 markus 836: status = ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
1.132 markus 837: recv_tok, &send_tok, &flags);
1.130 markus 838:
839: if (send_tok.length > 0) {
1.278 markus 840: u_char type = GSS_ERROR(status) ?
841: SSH2_MSG_USERAUTH_GSSAPI_ERRTOK :
842: SSH2_MSG_USERAUTH_GSSAPI_TOKEN;
843:
844: if ((r = sshpkt_start(ssh, type)) != 0 ||
845: (r = sshpkt_put_string(ssh, send_tok.value,
846: send_tok.length)) != 0 ||
847: (r = sshpkt_send(ssh)) != 0)
1.331 djm 848: fatal_fr(r, "send %u packet", type);
1.133 djm 849:
1.130 markus 850: gss_release_buffer(&ms, &send_tok);
851: }
1.133 djm 852:
1.130 markus 853: if (status == GSS_S_COMPLETE) {
1.132 markus 854: /* send either complete or MIC, depending on mechanism */
855: if (!(flags & GSS_C_INTEG_FLAG)) {
1.278 markus 856: if ((r = sshpkt_start(ssh,
857: SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE)) != 0 ||
858: (r = sshpkt_send(ssh)) != 0)
1.331 djm 859: fatal_fr(r, "send completion");
1.132 markus 860: } else {
1.278 markus 861: struct sshbuf *b;
862:
863: if ((b = sshbuf_new()) == NULL)
1.331 djm 864: fatal_f("sshbuf_new failed");
1.278 markus 865: ssh_gssapi_buildmic(b, authctxt->server_user,
1.346 djm 866: authctxt->service, "gssapi-with-mic",
867: ssh->kex->session_id);
1.132 markus 868:
1.278 markus 869: if ((gssbuf.value = sshbuf_mutable_ptr(b)) == NULL)
1.331 djm 870: fatal_f("sshbuf_mutable_ptr failed");
1.278 markus 871: gssbuf.length = sshbuf_len(b);
1.133 djm 872:
1.132 markus 873: status = ssh_gssapi_sign(gssctxt, &gssbuf, &mic);
1.133 djm 874:
1.132 markus 875: if (!GSS_ERROR(status)) {
1.278 markus 876: if ((r = sshpkt_start(ssh,
877: SSH2_MSG_USERAUTH_GSSAPI_MIC)) != 0 ||
878: (r = sshpkt_put_string(ssh, mic.value,
879: mic.length)) != 0 ||
880: (r = sshpkt_send(ssh)) != 0)
1.331 djm 881: fatal_fr(r, "send MIC");
1.132 markus 882: }
1.133 djm 883:
1.278 markus 884: sshbuf_free(b);
1.132 markus 885: gss_release_buffer(&ms, &mic);
1.133 djm 886: }
1.130 markus 887: }
1.133 djm 888:
1.130 markus 889: return status;
890: }
891:
1.169 djm 892: /* ARGSUSED */
1.302 djm 893: static int
1.261 markus 894: input_gssapi_response(int type, u_int32_t plen, struct ssh *ssh)
1.121 markus 895: {
1.260 markus 896: Authctxt *authctxt = ssh->authctxt;
1.121 markus 897: Gssctxt *gssctxt;
1.278 markus 898: size_t oidlen;
899: u_char *oidv = NULL;
900: int r;
1.121 markus 901:
902: if (authctxt == NULL)
903: fatal("input_gssapi_response: no authentication context");
904: gssctxt = authctxt->methoddata;
905:
906: /* Setup our OID */
1.278 markus 907: if ((r = sshpkt_get_string(ssh, &oidv, &oidlen)) != 0)
908: goto done;
1.121 markus 909:
1.129 markus 910: if (oidlen <= 2 ||
911: oidv[0] != SSH_GSS_OIDTYPE ||
912: oidv[1] != oidlen - 2) {
913: debug("Badly encoded mechanism OID received");
1.296 djm 914: userauth(ssh, NULL);
1.278 markus 915: goto ok;
1.121 markus 916: }
1.129 markus 917:
918: if (!ssh_gssapi_check_oid(gssctxt, oidv + 2, oidlen - 2))
919: fatal("Server returned different OID than expected");
1.121 markus 920:
1.278 markus 921: if ((r = sshpkt_get_end(ssh)) != 0)
922: goto done;
1.121 markus 923:
1.262 djm 924: if (GSS_ERROR(process_gssapi_token(ssh, GSS_C_NO_BUFFER))) {
1.121 markus 925: /* Start again with next method on list */
926: debug("Trying to start again");
1.296 djm 927: userauth(ssh, NULL);
1.278 markus 928: goto ok;
1.121 markus 929: }
1.278 markus 930: ok:
931: r = 0;
932: done:
933: free(oidv);
934: return r;
1.121 markus 935: }
936:
1.169 djm 937: /* ARGSUSED */
1.302 djm 938: static int
1.261 markus 939: input_gssapi_token(int type, u_int32_t plen, struct ssh *ssh)
1.121 markus 940: {
1.260 markus 941: Authctxt *authctxt = ssh->authctxt;
1.121 markus 942: gss_buffer_desc recv_tok;
1.278 markus 943: u_char *p = NULL;
944: size_t len;
1.130 markus 945: OM_uint32 status;
1.278 markus 946: int r;
1.121 markus 947:
948: if (authctxt == NULL)
949: fatal("input_gssapi_response: no authentication context");
950:
1.278 markus 951: if ((r = sshpkt_get_string(ssh, &p, &len)) != 0 ||
952: (r = sshpkt_get_end(ssh)) != 0)
953: goto out;
1.121 markus 954:
1.278 markus 955: recv_tok.value = p;
956: recv_tok.length = len;
1.262 djm 957: status = process_gssapi_token(ssh, &recv_tok);
1.121 markus 958:
1.278 markus 959: /* Start again with the next method in the list */
1.121 markus 960: if (GSS_ERROR(status)) {
1.296 djm 961: userauth(ssh, NULL);
1.278 markus 962: /* ok */
1.121 markus 963: }
1.278 markus 964: r = 0;
965: out:
966: free(p);
967: return r;
1.121 markus 968: }
969:
1.169 djm 970: /* ARGSUSED */
1.302 djm 971: static int
1.261 markus 972: input_gssapi_errtok(int type, u_int32_t plen, struct ssh *ssh)
1.121 markus 973: {
1.260 markus 974: Authctxt *authctxt = ssh->authctxt;
1.121 markus 975: Gssctxt *gssctxt;
976: gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
977: gss_buffer_desc recv_tok;
1.194 djm 978: OM_uint32 ms;
1.278 markus 979: u_char *p = NULL;
980: size_t len;
981: int r;
1.121 markus 982:
983: if (authctxt == NULL)
984: fatal("input_gssapi_response: no authentication context");
985: gssctxt = authctxt->methoddata;
986:
1.278 markus 987: if ((r = sshpkt_get_string(ssh, &p, &len)) != 0 ||
988: (r = sshpkt_get_end(ssh)) != 0) {
989: free(p);
990: return r;
991: }
1.121 markus 992:
993: /* Stick it into GSSAPI and see what it says */
1.278 markus 994: recv_tok.value = p;
995: recv_tok.length = len;
1.194 djm 996: (void)ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
1.140 djm 997: &recv_tok, &send_tok, NULL);
1.278 markus 998: free(p);
1.121 markus 999: gss_release_buffer(&ms, &send_tok);
1000:
1001: /* Server will be returning a failed packet after this one */
1.220 djm 1002: return 0;
1.121 markus 1003: }
1004:
1.169 djm 1005: /* ARGSUSED */
1.302 djm 1006: static int
1.261 markus 1007: input_gssapi_error(int type, u_int32_t plen, struct ssh *ssh)
1.121 markus 1008: {
1.278 markus 1009: char *msg = NULL;
1010: char *lang = NULL;
1011: int r;
1.121 markus 1012:
1.278 markus 1013: if ((r = sshpkt_get_u32(ssh, NULL)) != 0 || /* maj */
1014: (r = sshpkt_get_u32(ssh, NULL)) != 0 || /* min */
1015: (r = sshpkt_get_cstring(ssh, &msg, NULL)) != 0 ||
1016: (r = sshpkt_get_cstring(ssh, &lang, NULL)) != 0)
1017: goto out;
1018: r = sshpkt_get_end(ssh);
1.143 stevesk 1019: debug("Server GSSAPI Error:\n%s", msg);
1.278 markus 1020: out:
1.197 djm 1021: free(msg);
1022: free(lang);
1.278 markus 1023: return r;
1.121 markus 1024: }
1025: #endif /* GSSAPI */
1.20 markus 1026:
1.302 djm 1027: static int
1.295 djm 1028: userauth_none(struct ssh *ssh)
1.23 markus 1029: {
1.295 djm 1030: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.278 markus 1031: int r;
1032:
1.23 markus 1033: /* initial userauth request */
1.278 markus 1034: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1035: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1036: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1037: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1038: (r = sshpkt_send(ssh)) != 0)
1.331 djm 1039: fatal_fr(r, "send packet");
1.23 markus 1040: return 1;
1041: }
1042:
1.302 djm 1043: static int
1.295 djm 1044: userauth_passwd(struct ssh *ssh)
1.1 markus 1045: {
1.295 djm 1046: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.290 djm 1047: char *password, *prompt = NULL;
1.175 dtucker 1048: const char *host = options.host_key_alias ? options.host_key_alias :
1049: authctxt->host;
1.278 markus 1050: int r;
1.6 markus 1051:
1.292 djm 1052: if (authctxt->attempt_passwd++ >= options.number_of_password_prompts)
1.6 markus 1053: return 0;
1.13 todd 1054:
1.292 djm 1055: if (authctxt->attempt_passwd != 1)
1.13 todd 1056: error("Permission denied, please try again.");
1.1 markus 1057:
1.290 djm 1058: xasprintf(&prompt, "%s@%s's password: ", authctxt->server_user, host);
1.1 markus 1059: password = read_passphrase(prompt, 0);
1.278 markus 1060: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1061: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1062: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1063: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1064: (r = sshpkt_put_u8(ssh, 0)) != 0 ||
1065: (r = sshpkt_put_cstring(ssh, password)) != 0 ||
1066: (r = sshpkt_add_padding(ssh, 64)) != 0 ||
1067: (r = sshpkt_send(ssh)) != 0)
1.331 djm 1068: fatal_fr(r, "send packet");
1.99 markus 1069:
1.290 djm 1070: free(prompt);
1071: if (password != NULL)
1.278 markus 1072: freezero(password, strlen(password));
1073:
1074: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
1.99 markus 1075: &input_userauth_passwd_changereq);
1076:
1.1 markus 1077: return 1;
1078: }
1.169 djm 1079:
1.99 markus 1080: /*
1081: * parse PASSWD_CHANGEREQ, prompt user and send SSH2_MSG_USERAUTH_REQUEST
1082: */
1.169 djm 1083: /* ARGSUSED */
1.302 djm 1084: static int
1.261 markus 1085: input_userauth_passwd_changereq(int type, u_int32_t seqnr, struct ssh *ssh)
1.99 markus 1086: {
1.260 markus 1087: Authctxt *authctxt = ssh->authctxt;
1.278 markus 1088: char *info = NULL, *lang = NULL, *password = NULL, *retype = NULL;
1.266 dtucker 1089: char prompt[256];
1.252 djm 1090: const char *host;
1.278 markus 1091: int r;
1.99 markus 1092:
1093: debug2("input_userauth_passwd_changereq");
1094:
1095: if (authctxt == NULL)
1096: fatal("input_userauth_passwd_changereq: "
1097: "no authentication context");
1.252 djm 1098: host = options.host_key_alias ? options.host_key_alias : authctxt->host;
1.99 markus 1099:
1.278 markus 1100: if ((r = sshpkt_get_cstring(ssh, &info, NULL)) != 0 ||
1101: (r = sshpkt_get_cstring(ssh, &lang, NULL)) != 0)
1102: goto out;
1.99 markus 1103: if (strlen(info) > 0)
1.116 itojun 1104: logit("%s", info);
1.278 markus 1105: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1106: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1107: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1108: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1109: (r = sshpkt_put_u8(ssh, 1)) != 0) /* additional info */
1110: goto out;
1111:
1.104 deraadt 1112: snprintf(prompt, sizeof(prompt),
1.99 markus 1113: "Enter %.30s@%.128s's old password: ",
1.175 dtucker 1114: authctxt->server_user, host);
1.99 markus 1115: password = read_passphrase(prompt, 0);
1.278 markus 1116: if ((r = sshpkt_put_cstring(ssh, password)) != 0)
1117: goto out;
1118:
1119: freezero(password, strlen(password));
1.99 markus 1120: password = NULL;
1121: while (password == NULL) {
1.104 deraadt 1122: snprintf(prompt, sizeof(prompt),
1.99 markus 1123: "Enter %.30s@%.128s's new password: ",
1.175 dtucker 1124: authctxt->server_user, host);
1.99 markus 1125: password = read_passphrase(prompt, RP_ALLOW_EOF);
1126: if (password == NULL) {
1127: /* bail out */
1.278 markus 1128: r = 0;
1129: goto out;
1.99 markus 1130: }
1.104 deraadt 1131: snprintf(prompt, sizeof(prompt),
1.99 markus 1132: "Retype %.30s@%.128s's new password: ",
1.175 dtucker 1133: authctxt->server_user, host);
1.99 markus 1134: retype = read_passphrase(prompt, 0);
1135: if (strcmp(password, retype) != 0) {
1.278 markus 1136: freezero(password, strlen(password));
1.116 itojun 1137: logit("Mismatch; try again, EOF to quit.");
1.99 markus 1138: password = NULL;
1139: }
1.278 markus 1140: freezero(retype, strlen(retype));
1.99 markus 1141: }
1.278 markus 1142: if ((r = sshpkt_put_cstring(ssh, password)) != 0 ||
1143: (r = sshpkt_add_padding(ssh, 64)) != 0 ||
1144: (r = sshpkt_send(ssh)) != 0)
1145: goto out;
1.104 deraadt 1146:
1.278 markus 1147: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
1.99 markus 1148: &input_userauth_passwd_changereq);
1.278 markus 1149: r = 0;
1150: out:
1151: if (password)
1152: freezero(password, strlen(password));
1153: free(info);
1154: free(lang);
1155: return r;
1.117 markus 1156: }
1157:
1.272 djm 1158: /*
1159: * Select an algorithm for publickey signatures.
1160: * Returns algorithm (caller must free) or NULL if no mutual algorithm found.
1161: *
1162: * Call with ssh==NULL to ignore server-sig-algs extension list and
1163: * only attempt with the key's base signature type.
1164: */
1165: static char *
1166: key_sig_algorithm(struct ssh *ssh, const struct sshkey *key)
1.231 markus 1167: {
1.274 djm 1168: char *allowed, *oallowed, *cp, *tmp, *alg = NULL;
1.348 djm 1169: const char *server_sig_algs;
1.231 markus 1170:
1.272 djm 1171: /*
1172: * The signature algorithm will only differ from the key algorithm
1173: * for RSA keys/certs and when the server advertises support for
1174: * newer (SHA2) algorithms.
1175: */
1176: if (ssh == NULL || ssh->kex->server_sig_algs == NULL ||
1.288 djm 1177: (key->type != KEY_RSA && key->type != KEY_RSA_CERT) ||
1.345 djm 1178: (key->type == KEY_RSA_CERT && (ssh->compat & SSH_BUG_SIGTYPE))) {
1.272 djm 1179: /* Filter base key signature alg against our configuration */
1.279 markus 1180: return match_list(sshkey_ssh_name(key),
1.342 dtucker 1181: options.pubkey_accepted_algos, NULL);
1.231 markus 1182: }
1183:
1.272 djm 1184: /*
1.348 djm 1185: * Workaround OpenSSH 7.4 bug: this version supports RSA/SHA-2 but
1186: * fails to advertise it via SSH2_MSG_EXT_INFO.
1187: */
1188: server_sig_algs = ssh->kex->server_sig_algs;
1189: if (key->type == KEY_RSA && (ssh->compat & SSH_BUG_SIGTYPE74))
1190: server_sig_algs = "rsa-sha2-256,rsa-sha2-512";
1191:
1192: /*
1.272 djm 1193: * For RSA keys/certs, since these might have a different sig type:
1.342 dtucker 1194: * find the first entry in PubkeyAcceptedAlgorithms of the right type
1.272 djm 1195: * that also appears in the supported signature algorithms list from
1196: * the server.
1197: */
1.342 dtucker 1198: oallowed = allowed = xstrdup(options.pubkey_accepted_algos);
1.272 djm 1199: while ((cp = strsep(&allowed, ",")) != NULL) {
1200: if (sshkey_type_from_name(cp) != key->type)
1201: continue;
1.323 djm 1202: tmp = match_list(sshkey_sigalg_by_name(cp),
1.348 djm 1203: server_sig_algs, NULL);
1.274 djm 1204: if (tmp != NULL)
1205: alg = xstrdup(cp);
1206: free(tmp);
1.272 djm 1207: if (alg != NULL)
1208: break;
1.269 djm 1209: }
1.272 djm 1210: free(oallowed);
1211: return alg;
1.269 djm 1212: }
1213:
1.117 markus 1214: static int
1.214 djm 1215: identity_sign(struct identity *id, u_char **sigp, size_t *lenp,
1.272 djm 1216: const u_char *data, size_t datalen, u_int compat, const char *alg)
1.117 markus 1217: {
1.309 djm 1218: struct sshkey *sign_key = NULL, *prv = NULL;
1.341 djm 1219: int retried = 0, r = SSH_ERR_INTERNAL_ERROR;
1.312 djm 1220: struct notifier_ctx *notifier = NULL;
1.325 djm 1221: char *fp = NULL, *pin = NULL, *prompt = NULL;
1.309 djm 1222:
1223: *sigp = NULL;
1224: *lenp = 0;
1.99 markus 1225:
1.272 djm 1226: /* The agent supports this key. */
1.269 djm 1227: if (id->key != NULL && id->agent_fd != -1) {
1.272 djm 1228: return ssh_agent_sign(id->agent_fd, id->key, sigp, lenp,
1229: data, datalen, alg, compat);
1.269 djm 1230: }
1.214 djm 1231:
1.117 markus 1232: /*
1.272 djm 1233: * We have already loaded the private key or the private key is
1234: * stored in external hardware.
1.117 markus 1235: */
1.255 djm 1236: if (id->key != NULL &&
1.272 djm 1237: (id->isprivate || (id->key->flags & SSHKEY_FLAG_EXT))) {
1.309 djm 1238: sign_key = id->key;
1239: } else {
1240: /* Load the private key from the file. */
1241: if ((prv = load_identity_file(id)) == NULL)
1242: return SSH_ERR_KEY_NOT_FOUND;
1243: if (id->key != NULL && !sshkey_equal_public(prv, id->key)) {
1.331 djm 1244: error_f("private key %s contents do not match public",
1.347 djm 1245: id->filename);
1.309 djm 1246: r = SSH_ERR_KEY_NOT_FOUND;
1247: goto out;
1248: }
1249: sign_key = prv;
1.325 djm 1250: if (sshkey_is_sk(sign_key)) {
1251: if ((sign_key->sk_flags &
1252: SSH_SK_USER_VERIFICATION_REQD)) {
1.341 djm 1253: retry_pin:
1.325 djm 1254: xasprintf(&prompt, "Enter PIN for %s key %s: ",
1255: sshkey_type(sign_key), id->filename);
1256: pin = read_passphrase(prompt, 0);
1257: }
1258: if ((sign_key->sk_flags & SSH_SK_USER_PRESENCE_REQD)) {
1259: /* XXX should batch mode just skip these? */
1260: if ((fp = sshkey_fingerprint(sign_key,
1261: options.fingerprint_hash,
1262: SSH_FP_DEFAULT)) == NULL)
1.331 djm 1263: fatal_f("fingerprint failed");
1.325 djm 1264: notifier = notify_start(options.batch_mode,
1265: "Confirm user presence for key %s %s",
1266: sshkey_type(sign_key), fp);
1267: free(fp);
1268: }
1.312 djm 1269: }
1.272 djm 1270: }
1.310 djm 1271: if ((r = sshkey_sign(sign_key, sigp, lenp, data, datalen,
1.325 djm 1272: alg, options.sk_provider, pin, compat)) != 0) {
1.331 djm 1273: debug_fr(r, "sshkey_sign");
1.341 djm 1274: if (pin == NULL && !retried && sshkey_is_sk(sign_key) &&
1275: r == SSH_ERR_KEY_WRONG_PASSPHRASE) {
1276: notify_complete(notifier, NULL);
1277: notifier = NULL;
1278: retried = 1;
1279: goto retry_pin;
1280: }
1.309 djm 1281: goto out;
1282: }
1.341 djm 1283:
1.309 djm 1284: /*
1285: * PKCS#11 tokens may not support all signature algorithms,
1286: * so check what we get back.
1287: */
1288: if ((r = sshkey_check_sigtype(*sigp, *lenp, alg)) != 0) {
1.331 djm 1289: debug_fr(r, "sshkey_check_sigtype");
1.309 djm 1290: goto out;
1.265 djm 1291: }
1.309 djm 1292: /* success */
1293: r = 0;
1294: out:
1.325 djm 1295: free(prompt);
1296: if (pin != NULL)
1297: freezero(pin, strlen(pin));
1.341 djm 1298: notify_complete(notifier, r == 0 ? "User presence confirmed" : NULL);
1.214 djm 1299: sshkey_free(prv);
1.269 djm 1300: return r;
1.51 markus 1301: }
1302:
1.76 itojun 1303: static int
1.255 djm 1304: id_filename_matches(Identity *id, Identity *private_id)
1305: {
1306: const char *suffixes[] = { ".pub", "-cert.pub", NULL };
1307: size_t len = strlen(id->filename), plen = strlen(private_id->filename);
1308: size_t i, slen;
1309:
1310: if (strcmp(id->filename, private_id->filename) == 0)
1311: return 1;
1312: for (i = 0; suffixes[i]; i++) {
1313: slen = strlen(suffixes[i]);
1314: if (len > slen && plen == len - slen &&
1315: strcmp(id->filename + (len - slen), suffixes[i]) == 0 &&
1316: memcmp(id->filename, private_id->filename, plen) == 0)
1317: return 1;
1318: }
1319: return 0;
1320: }
1321:
1322: static int
1.295 djm 1323: sign_and_send_pubkey(struct ssh *ssh, Identity *id)
1.1 markus 1324: {
1.295 djm 1325: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.272 djm 1326: struct sshbuf *b = NULL;
1327: Identity *private_id, *sign_id = NULL;
1328: u_char *signature = NULL;
1329: size_t slen = 0, skip = 0;
1330: int r, fallback_sigtype, sent = 0;
1331: char *alg = NULL, *fp = NULL;
1332: const char *loc = "";
1.1 markus 1333:
1.222 djm 1334: if ((fp = sshkey_fingerprint(id->key, options.fingerprint_hash,
1335: SSH_FP_DEFAULT)) == NULL)
1336: return 0;
1.51 markus 1337:
1.331 djm 1338: debug3_f("%s %s", sshkey_type(id->key), fp);
1.1 markus 1339:
1.227 djm 1340: /*
1341: * If the key is an certificate, try to find a matching private key
1342: * and use it to complete the signature.
1.241 djm 1343: * If no such private key exists, fall back to trying the certificate
1344: * key itself in case it has a private half already loaded.
1.272 djm 1345: * This will try to set sign_id to the private key that will perform
1346: * the signature.
1.227 djm 1347: */
1.272 djm 1348: if (sshkey_is_cert(id->key)) {
1.227 djm 1349: TAILQ_FOREACH(private_id, &authctxt->keys, next) {
1350: if (sshkey_equal_public(id->key, private_id->key) &&
1351: id->key->type != private_id->key->type) {
1.272 djm 1352: sign_id = private_id;
1.227 djm 1353: break;
1354: }
1355: }
1.255 djm 1356: /*
1357: * Exact key matches are preferred, but also allow
1358: * filename matches for non-PKCS#11/agent keys that
1359: * didn't load public keys. This supports the case
1360: * of keeping just a private key file and public
1361: * certificate on disk.
1362: */
1.272 djm 1363: if (sign_id == NULL &&
1364: !id->isprivate && id->agent_fd == -1 &&
1.255 djm 1365: (id->key->flags & SSHKEY_FLAG_EXT) == 0) {
1366: TAILQ_FOREACH(private_id, &authctxt->keys, next) {
1367: if (private_id->key == NULL &&
1368: id_filename_matches(id, private_id)) {
1.272 djm 1369: sign_id = private_id;
1.255 djm 1370: break;
1371: }
1372: }
1373: }
1.272 djm 1374: if (sign_id != NULL) {
1.331 djm 1375: debug2_f("using private key \"%s\"%s for "
1.349 djm 1376: "certificate", sign_id->filename,
1377: sign_id->agent_fd != -1 ? " from agent" : "");
1.227 djm 1378: } else {
1.331 djm 1379: debug_f("no separate private key for certificate "
1380: "\"%s\"", id->filename);
1.227 djm 1381: }
1382: }
1383:
1.272 djm 1384: /*
1385: * If the above didn't select another identity to do the signing
1386: * then default to the one we started with.
1387: */
1388: if (sign_id == NULL)
1389: sign_id = id;
1390:
1391: /* assemble and sign data */
1392: for (fallback_sigtype = 0; fallback_sigtype <= 1; fallback_sigtype++) {
1393: free(alg);
1394: slen = 0;
1395: signature = NULL;
1396: if ((alg = key_sig_algorithm(fallback_sigtype ? NULL : ssh,
1397: id->key)) == NULL) {
1.331 djm 1398: error_f("no mutual signature supported");
1.272 djm 1399: goto out;
1400: }
1.331 djm 1401: debug3_f("signing using %s %s", alg, fp);
1.272 djm 1402:
1403: sshbuf_free(b);
1404: if ((b = sshbuf_new()) == NULL)
1.331 djm 1405: fatal_f("sshbuf_new failed");
1.345 djm 1406: if (ssh->compat & SSH_OLD_SESSIONID) {
1.346 djm 1407: if ((r = sshbuf_putb(b, ssh->kex->session_id)) != 0)
1408: fatal_fr(r, "sshbuf_putb");
1.272 djm 1409: } else {
1.346 djm 1410: if ((r = sshbuf_put_stringb(b,
1411: ssh->kex->session_id)) != 0)
1412: fatal_fr(r, "sshbuf_put_stringb");
1.272 djm 1413: }
1.278 markus 1414: skip = sshbuf_len(b);
1.272 djm 1415: if ((r = sshbuf_put_u8(b, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1416: (r = sshbuf_put_cstring(b, authctxt->server_user)) != 0 ||
1417: (r = sshbuf_put_cstring(b, authctxt->service)) != 0 ||
1418: (r = sshbuf_put_cstring(b, authctxt->method->name)) != 0 ||
1419: (r = sshbuf_put_u8(b, 1)) != 0 ||
1420: (r = sshbuf_put_cstring(b, alg)) != 0 ||
1421: (r = sshkey_puts(id->key, b)) != 0) {
1.331 djm 1422: fatal_fr(r, "assemble signed data");
1.272 djm 1423: }
1424:
1425: /* generate signature */
1426: r = identity_sign(sign_id, &signature, &slen,
1.345 djm 1427: sshbuf_ptr(b), sshbuf_len(b), ssh->compat, alg);
1.272 djm 1428: if (r == 0)
1429: break;
1430: else if (r == SSH_ERR_KEY_NOT_FOUND)
1431: goto out; /* soft failure */
1432: else if (r == SSH_ERR_SIGN_ALG_UNSUPPORTED &&
1433: !fallback_sigtype) {
1434: if (sign_id->agent_fd != -1)
1435: loc = "agent ";
1436: else if ((sign_id->key->flags & SSHKEY_FLAG_EXT) != 0)
1437: loc = "token ";
1438: logit("%skey %s %s returned incorrect signature type",
1439: loc, sshkey_type(id->key), fp);
1440: continue;
1441: }
1.331 djm 1442: error_fr(r, "signing failed for %s \"%s\"%s",
1.315 djm 1443: sshkey_type(sign_id->key), sign_id->filename,
1.331 djm 1444: id->agent_fd != -1 ? " from agent" : "");
1.272 djm 1445: goto out;
1.17 markus 1446: }
1.272 djm 1447: if (slen == 0 || signature == NULL) /* shouldn't happen */
1.331 djm 1448: fatal_f("no signature");
1.51 markus 1449:
1.1 markus 1450: /* append signature */
1.272 djm 1451: if ((r = sshbuf_put_string(b, signature, slen)) != 0)
1.331 djm 1452: fatal_fr(r, "append signature");
1.1 markus 1453:
1.272 djm 1454: #ifdef DEBUG_PK
1455: sshbuf_dump(b, stderr);
1456: #endif
1.1 markus 1457: /* skip session id and packet type */
1.272 djm 1458: if ((r = sshbuf_consume(b, skip + 1)) != 0)
1.331 djm 1459: fatal_fr(r, "consume");
1.1 markus 1460:
1461: /* put remaining data from buffer into packet */
1.272 djm 1462: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1463: (r = sshpkt_putb(ssh, b)) != 0 ||
1464: (r = sshpkt_send(ssh)) != 0)
1.331 djm 1465: fatal_fr(r, "enqueue request");
1.272 djm 1466:
1467: /* success */
1468: sent = 1;
1.17 markus 1469:
1.272 djm 1470: out:
1471: free(fp);
1472: free(alg);
1473: sshbuf_free(b);
1474: freezero(signature, slen);
1475: return sent;
1.16 markus 1476: }
1477:
1.76 itojun 1478: static int
1.295 djm 1479: send_pubkey_test(struct ssh *ssh, Identity *id)
1.20 markus 1480: {
1.295 djm 1481: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.272 djm 1482: u_char *blob = NULL;
1483: char *alg = NULL;
1.278 markus 1484: size_t bloblen;
1485: u_int have_sig = 0;
1486: int sent = 0, r;
1.20 markus 1487:
1.272 djm 1488: if ((alg = key_sig_algorithm(ssh, id->key)) == NULL) {
1.331 djm 1489: debug_f("no mutual signature algorithm");
1.272 djm 1490: goto out;
1491: }
1.16 markus 1492:
1.278 markus 1493: if ((r = sshkey_to_blob(id->key, &blob, &bloblen)) != 0) {
1.51 markus 1494: /* we cannot handle this key */
1.331 djm 1495: debug3_f("cannot handle key");
1.272 djm 1496: goto out;
1.16 markus 1497: }
1.51 markus 1498: /* register callback for USERAUTH_PK_OK message */
1.278 markus 1499: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_PK_OK, &input_userauth_pk_ok);
1.51 markus 1500:
1.278 markus 1501: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1502: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1503: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1504: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1505: (r = sshpkt_put_u8(ssh, have_sig)) != 0 ||
1506: (r = sshpkt_put_cstring(ssh, alg)) != 0 ||
1507: (r = sshpkt_put_string(ssh, blob, bloblen)) != 0 ||
1508: (r = sshpkt_send(ssh)) != 0)
1.331 djm 1509: fatal_fr(r, "send packet");
1.272 djm 1510: sent = 1;
1.278 markus 1511:
1512: out:
1.272 djm 1513: free(alg);
1.197 djm 1514: free(blob);
1.272 djm 1515: return sent;
1.51 markus 1516: }
1517:
1.259 markus 1518: static struct sshkey *
1.229 jcs 1519: load_identity_file(Identity *id)
1.51 markus 1520: {
1.259 markus 1521: struct sshkey *private = NULL;
1.229 jcs 1522: char prompt[300], *passphrase, *comment;
1.308 dtucker 1523: int r, quit = 0, i;
1.52 markus 1524: struct stat st;
1.16 markus 1525:
1.306 deraadt 1526: if (stat(id->filename, &st) == -1) {
1.330 djm 1527: do_log2(id->userprovided ?
1528: SYSLOG_LEVEL_INFO : SYSLOG_LEVEL_DEBUG3,
1529: "no such identity: %s: %s", id->filename, strerror(errno));
1.52 markus 1530: return NULL;
1531: }
1.214 djm 1532: snprintf(prompt, sizeof prompt,
1.229 jcs 1533: "Enter passphrase for key '%.100s': ", id->filename);
1.214 djm 1534: for (i = 0; i <= options.number_of_password_prompts; i++) {
1535: if (i == 0)
1536: passphrase = "";
1537: else {
1.20 markus 1538: passphrase = read_passphrase(prompt, 0);
1.214 djm 1539: if (*passphrase == '\0') {
1.20 markus 1540: debug2("no passphrase given, try next key");
1.214 djm 1541: free(passphrase);
1542: break;
1543: }
1544: }
1.229 jcs 1545: switch ((r = sshkey_load_private_type(KEY_UNSPEC, id->filename,
1.308 dtucker 1546: passphrase, &private, &comment))) {
1.214 djm 1547: case 0:
1548: break;
1549: case SSH_ERR_KEY_WRONG_PASSPHRASE:
1550: if (options.batch_mode) {
1551: quit = 1;
1552: break;
1553: }
1.215 djm 1554: if (i != 0)
1555: debug2("bad passphrase given, try again...");
1.214 djm 1556: break;
1557: case SSH_ERR_SYSTEM_ERROR:
1558: if (errno == ENOENT) {
1.331 djm 1559: debug2_r(r, "Load key \"%s\"", id->filename);
1.51 markus 1560: quit = 1;
1.214 djm 1561: break;
1.20 markus 1562: }
1.214 djm 1563: /* FALLTHROUGH */
1564: default:
1.331 djm 1565: error_r(r, "Load key \"%s\"", id->filename);
1.214 djm 1566: quit = 1;
1567: break;
1568: }
1.311 markus 1569: if (private != NULL && sshkey_is_sk(private) &&
1.309 djm 1570: options.sk_provider == NULL) {
1.319 naddy 1571: debug("key \"%s\" is an authenticator-hosted key, "
1572: "but no provider specified", id->filename);
1.309 djm 1573: sshkey_free(private);
1574: private = NULL;
1575: quit = 1;
1576: }
1.230 djm 1577: if (!quit && private != NULL && id->agent_fd == -1 &&
1.229 jcs 1578: !(id->key && id->isprivate))
1579: maybe_add_key_to_agent(id->filename, private, comment,
1580: passphrase);
1.278 markus 1581: if (i > 0)
1582: freezero(passphrase, strlen(passphrase));
1.232 mmcc 1583: free(comment);
1.214 djm 1584: if (private != NULL || quit)
1585: break;
1.16 markus 1586: }
1.51 markus 1587: return private;
1588: }
1589:
1.272 djm 1590: static int
1591: key_type_allowed_by_config(struct sshkey *key)
1592: {
1593: if (match_pattern_list(sshkey_ssh_name(key),
1.342 dtucker 1594: options.pubkey_accepted_algos, 0) == 1)
1.272 djm 1595: return 1;
1596:
1597: /* RSA keys/certs might be allowed by alternate signature types */
1598: switch (key->type) {
1599: case KEY_RSA:
1600: if (match_pattern_list("rsa-sha2-512",
1.342 dtucker 1601: options.pubkey_accepted_algos, 0) == 1)
1.272 djm 1602: return 1;
1603: if (match_pattern_list("rsa-sha2-256",
1.342 dtucker 1604: options.pubkey_accepted_algos, 0) == 1)
1.272 djm 1605: return 1;
1606: break;
1607: case KEY_RSA_CERT:
1608: if (match_pattern_list("rsa-sha2-512-cert-v01@openssh.com",
1.342 dtucker 1609: options.pubkey_accepted_algos, 0) == 1)
1.272 djm 1610: return 1;
1611: if (match_pattern_list("rsa-sha2-256-cert-v01@openssh.com",
1.342 dtucker 1612: options.pubkey_accepted_algos, 0) == 1)
1.272 djm 1613: return 1;
1614: break;
1615: }
1616: return 0;
1617: }
1618:
1619:
1.117 markus 1620: /*
1621: * try keys in the following order:
1.332 djm 1622: * 1. certificates listed in the config file
1623: * 2. other input certificates
1.227 djm 1624: * 3. agent keys that are found in the config file
1625: * 4. other agent keys
1626: * 5. keys that are only listed in the config file
1.117 markus 1627: */
1628: static void
1629: pubkey_prepare(Authctxt *authctxt)
1.51 markus 1630: {
1.214 djm 1631: struct identity *id, *id2, *tmp;
1632: struct idlist agent, files, *preferred;
1633: struct sshkey *key;
1.230 djm 1634: int agent_fd = -1, i, r, found;
1.214 djm 1635: size_t j;
1636: struct ssh_identitylist *idlist;
1.287 djm 1637: char *ident;
1.51 markus 1638:
1.117 markus 1639: TAILQ_INIT(&agent); /* keys from the agent */
1640: TAILQ_INIT(&files); /* keys from the config file */
1641: preferred = &authctxt->keys;
1642: TAILQ_INIT(preferred); /* preferred order of keys */
1643:
1.190 djm 1644: /* list of keys stored in the filesystem and PKCS#11 */
1.117 markus 1645: for (i = 0; i < options.num_identity_files; i++) {
1646: key = options.identity_keys[i];
1.309 djm 1647: if (key && key->cert &&
1648: key->cert->type != SSH2_CERT_TYPE_USER) {
1.331 djm 1649: debug_f("ignoring certificate %s: not a user "
1650: "certificate", options.identity_files[i]);
1.309 djm 1651: continue;
1652: }
1.311 markus 1653: if (key && sshkey_is_sk(key) && options.sk_provider == NULL) {
1.331 djm 1654: debug_f("ignoring authenticator-hosted key %s as no "
1.309 djm 1655: "SecurityKeyProvider has been specified",
1.331 djm 1656: options.identity_files[i]);
1.117 markus 1657: continue;
1.309 djm 1658: }
1.117 markus 1659: options.identity_keys[i] = NULL;
1.150 djm 1660: id = xcalloc(1, sizeof(*id));
1.230 djm 1661: id->agent_fd = -1;
1.117 markus 1662: id->key = key;
1663: id->filename = xstrdup(options.identity_files[i]);
1.192 dtucker 1664: id->userprovided = options.identity_file_userprovided[i];
1.117 markus 1665: TAILQ_INSERT_TAIL(&files, id, next);
1.190 djm 1666: }
1.227 djm 1667: /* list of certificates specified by user */
1668: for (i = 0; i < options.num_certificate_files; i++) {
1669: key = options.certificates[i];
1.278 markus 1670: if (!sshkey_is_cert(key) || key->cert == NULL ||
1.309 djm 1671: key->cert->type != SSH2_CERT_TYPE_USER) {
1.331 djm 1672: debug_f("ignoring certificate %s: not a user "
1673: "certificate", options.identity_files[i]);
1.227 djm 1674: continue;
1.309 djm 1675: }
1.311 markus 1676: if (key && sshkey_is_sk(key) && options.sk_provider == NULL) {
1.331 djm 1677: debug_f("ignoring authenticator-hosted key "
1.319 naddy 1678: "certificate %s as no "
1.309 djm 1679: "SecurityKeyProvider has been specified",
1.331 djm 1680: options.identity_files[i]);
1.309 djm 1681: continue;
1682: }
1.227 djm 1683: id = xcalloc(1, sizeof(*id));
1.230 djm 1684: id->agent_fd = -1;
1.227 djm 1685: id->key = key;
1686: id->filename = xstrdup(options.certificate_files[i]);
1687: id->userprovided = options.certificate_file_userprovided[i];
1688: TAILQ_INSERT_TAIL(preferred, id, next);
1.117 markus 1689: }
1690: /* list of keys supported by the agent */
1.214 djm 1691: if ((r = ssh_get_authentication_socket(&agent_fd)) != 0) {
1692: if (r != SSH_ERR_AGENT_NOT_PRESENT)
1.331 djm 1693: debug_fr(r, "ssh_get_authentication_socket");
1.258 naddy 1694: } else if ((r = ssh_fetch_identitylist(agent_fd, &idlist)) != 0) {
1.214 djm 1695: if (r != SSH_ERR_AGENT_NO_IDENTITIES)
1.331 djm 1696: debug_fr(r, "ssh_fetch_identitylist");
1.237 markus 1697: close(agent_fd);
1.214 djm 1698: } else {
1699: for (j = 0; j < idlist->nkeys; j++) {
1.117 markus 1700: found = 0;
1701: TAILQ_FOREACH(id, &files, next) {
1.214 djm 1702: /*
1703: * agent keys from the config file are
1704: * preferred
1705: */
1706: if (sshkey_equal(idlist->keys[j], id->key)) {
1.117 markus 1707: TAILQ_REMOVE(&files, id, next);
1708: TAILQ_INSERT_TAIL(preferred, id, next);
1.214 djm 1709: id->agent_fd = agent_fd;
1.117 markus 1710: found = 1;
1711: break;
1712: }
1713: }
1.135 markus 1714: if (!found && !options.identities_only) {
1.150 djm 1715: id = xcalloc(1, sizeof(*id));
1.214 djm 1716: /* XXX "steals" key/comment from idlist */
1717: id->key = idlist->keys[j];
1718: id->filename = idlist->comments[j];
1719: idlist->keys[j] = NULL;
1720: idlist->comments[j] = NULL;
1721: id->agent_fd = agent_fd;
1.117 markus 1722: TAILQ_INSERT_TAIL(&agent, id, next);
1723: }
1724: }
1.214 djm 1725: ssh_free_identitylist(idlist);
1.117 markus 1726: /* append remaining agent keys */
1.324 bket 1727: TAILQ_CONCAT(preferred, &agent, next);
1.214 djm 1728: authctxt->agent_fd = agent_fd;
1.244 djm 1729: }
1730: /* Prefer PKCS11 keys that are explicitly listed */
1731: TAILQ_FOREACH_SAFE(id, &files, next, tmp) {
1732: if (id->key == NULL || (id->key->flags & SSHKEY_FLAG_EXT) == 0)
1733: continue;
1734: found = 0;
1735: TAILQ_FOREACH(id2, &files, next) {
1736: if (id2->key == NULL ||
1.321 djm 1737: (id2->key->flags & SSHKEY_FLAG_EXT) != 0)
1.244 djm 1738: continue;
1739: if (sshkey_equal(id->key, id2->key)) {
1740: TAILQ_REMOVE(&files, id, next);
1741: TAILQ_INSERT_TAIL(preferred, id, next);
1742: found = 1;
1743: break;
1744: }
1745: }
1746: /* If IdentitiesOnly set and key not found then don't use it */
1747: if (!found && options.identities_only) {
1748: TAILQ_REMOVE(&files, id, next);
1.278 markus 1749: freezero(id, sizeof(*id));
1.244 djm 1750: }
1.117 markus 1751: }
1752: /* append remaining keys from the config file */
1.324 bket 1753: TAILQ_CONCAT(preferred, &files, next);
1.342 dtucker 1754: /* finally, filter by PubkeyAcceptedAlgorithms */
1.228 djm 1755: TAILQ_FOREACH_SAFE(id, preferred, next, id2) {
1.273 djm 1756: if (id->key != NULL && !key_type_allowed_by_config(id->key)) {
1.228 djm 1757: debug("Skipping %s key %s - "
1.342 dtucker 1758: "corresponding algo not in PubkeyAcceptedAlgorithms",
1.228 djm 1759: sshkey_ssh_name(id->key), id->filename);
1760: TAILQ_REMOVE(preferred, id, next);
1761: sshkey_free(id->key);
1762: free(id->filename);
1763: memset(id, 0, sizeof(*id));
1764: continue;
1765: }
1.117 markus 1766: }
1.287 djm 1767: /* List the keys we plan on using */
1768: TAILQ_FOREACH_SAFE(id, preferred, next, id2) {
1769: ident = format_identity(id);
1770: debug("Will attempt key: %s", ident);
1771: free(ident);
1772: }
1.331 djm 1773: debug2_f("done");
1.17 markus 1774: }
1775:
1.117 markus 1776: static void
1.303 djm 1777: pubkey_cleanup(struct ssh *ssh)
1.51 markus 1778: {
1.302 djm 1779: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.117 markus 1780: Identity *id;
1.51 markus 1781:
1.289 djm 1782: if (authctxt->agent_fd != -1) {
1.214 djm 1783: ssh_close_authentication_socket(authctxt->agent_fd);
1.289 djm 1784: authctxt->agent_fd = -1;
1785: }
1.117 markus 1786: for (id = TAILQ_FIRST(&authctxt->keys); id;
1787: id = TAILQ_FIRST(&authctxt->keys)) {
1788: TAILQ_REMOVE(&authctxt->keys, id, next);
1.235 mmcc 1789: sshkey_free(id->key);
1.197 djm 1790: free(id->filename);
1791: free(id);
1.117 markus 1792: }
1.1 markus 1793: }
1794:
1.251 djm 1795: static void
1796: pubkey_reset(Authctxt *authctxt)
1797: {
1798: Identity *id;
1799:
1800: TAILQ_FOREACH(id, &authctxt->keys, next)
1801: id->tried = 0;
1802: }
1803:
1.225 markus 1804: static int
1.345 djm 1805: try_identity(struct ssh *ssh, Identity *id)
1.225 markus 1806: {
1807: if (!id->key)
1808: return (0);
1.279 markus 1809: if (sshkey_type_plain(id->key->type) == KEY_RSA &&
1.345 djm 1810: (ssh->compat & SSH_BUG_RSASIGMD5) != 0) {
1.225 markus 1811: debug("Skipped %s key %s for RSA/MD5 server",
1.279 markus 1812: sshkey_type(id->key), id->filename);
1.225 markus 1813: return (0);
1814: }
1.257 djm 1815: return 1;
1.225 markus 1816: }
1817:
1.302 djm 1818: static int
1.295 djm 1819: userauth_pubkey(struct ssh *ssh)
1.20 markus 1820: {
1.295 djm 1821: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.117 markus 1822: Identity *id;
1.20 markus 1823: int sent = 0;
1.287 djm 1824: char *ident;
1.20 markus 1825:
1.117 markus 1826: while ((id = TAILQ_FIRST(&authctxt->keys))) {
1827: if (id->tried++)
1828: return (0);
1.127 markus 1829: /* move key to the end of the queue */
1.117 markus 1830: TAILQ_REMOVE(&authctxt->keys, id, next);
1831: TAILQ_INSERT_TAIL(&authctxt->keys, id, next);
1832: /*
1833: * send a test message if we have the public key. for
1834: * encrypted keys we cannot do this and have to load the
1835: * private key instead
1836: */
1.200 djm 1837: if (id->key != NULL) {
1.345 djm 1838: if (try_identity(ssh, id)) {
1.287 djm 1839: ident = format_identity(id);
1840: debug("Offering public key: %s", ident);
1841: free(ident);
1.295 djm 1842: sent = send_pubkey_test(ssh, id);
1.200 djm 1843: }
1844: } else {
1.117 markus 1845: debug("Trying private key: %s", id->filename);
1.229 jcs 1846: id->key = load_identity_file(id);
1.117 markus 1847: if (id->key != NULL) {
1.345 djm 1848: if (try_identity(ssh, id)) {
1.225 markus 1849: id->isprivate = 1;
1.295 djm 1850: sent = sign_and_send_pubkey(ssh, id);
1.200 djm 1851: }
1.278 markus 1852: sshkey_free(id->key);
1.117 markus 1853: id->key = NULL;
1.251 djm 1854: id->isprivate = 0;
1.51 markus 1855: }
1856: }
1.117 markus 1857: if (sent)
1858: return (sent);
1.28 markus 1859: }
1.117 markus 1860: return (0);
1.20 markus 1861: }
1862:
1.23 markus 1863: /*
1864: * Send userauth request message specifying keyboard-interactive method.
1865: */
1.302 djm 1866: static int
1.295 djm 1867: userauth_kbdint(struct ssh *ssh)
1.23 markus 1868: {
1.295 djm 1869: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.278 markus 1870: int r;
1.23 markus 1871:
1.292 djm 1872: if (authctxt->attempt_kbdint++ >= options.number_of_password_prompts)
1.23 markus 1873: return 0;
1.82 markus 1874: /* disable if no SSH2_MSG_USERAUTH_INFO_REQUEST has been seen */
1.292 djm 1875: if (authctxt->attempt_kbdint > 1 && !authctxt->info_req_seen) {
1.82 markus 1876: debug3("userauth_kbdint: disable: no info_req_seen");
1.278 markus 1877: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_INFO_REQUEST, NULL);
1.82 markus 1878: return 0;
1879: }
1.23 markus 1880:
1881: debug2("userauth_kbdint");
1.278 markus 1882: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1883: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1884: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1885: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1886: (r = sshpkt_put_cstring(ssh, "")) != 0 || /* lang */
1887: (r = sshpkt_put_cstring(ssh, options.kbd_interactive_devices ?
1888: options.kbd_interactive_devices : "")) != 0 ||
1889: (r = sshpkt_send(ssh)) != 0)
1.331 djm 1890: fatal_fr(r, "send packet");
1.23 markus 1891:
1.278 markus 1892: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_INFO_REQUEST, &input_userauth_info_req);
1.23 markus 1893: return 1;
1894: }
1895:
1896: /*
1.46 markus 1897: * parse INFO_REQUEST, prompt user and send INFO_RESPONSE
1.23 markus 1898: */
1.302 djm 1899: static int
1.261 markus 1900: input_userauth_info_req(int type, u_int32_t seq, struct ssh *ssh)
1.23 markus 1901: {
1.260 markus 1902: Authctxt *authctxt = ssh->authctxt;
1.278 markus 1903: char *name = NULL, *inst = NULL, *lang = NULL, *prompt = NULL;
1.335 djm 1904: char *display_prompt = NULL, *response = NULL;
1.278 markus 1905: u_char echo = 0;
1.32 markus 1906: u_int num_prompts, i;
1.278 markus 1907: int r;
1.23 markus 1908:
1.335 djm 1909: debug2_f("entering");
1.23 markus 1910:
1911: if (authctxt == NULL)
1.335 djm 1912: fatal_f("no authentication context");
1.82 markus 1913:
1914: authctxt->info_req_seen = 1;
1.23 markus 1915:
1.278 markus 1916: if ((r = sshpkt_get_cstring(ssh, &name, NULL)) != 0 ||
1917: (r = sshpkt_get_cstring(ssh, &inst, NULL)) != 0 ||
1918: (r = sshpkt_get_cstring(ssh, &lang, NULL)) != 0)
1919: goto out;
1.23 markus 1920: if (strlen(name) > 0)
1.116 itojun 1921: logit("%s", name);
1.23 markus 1922: if (strlen(inst) > 0)
1.116 itojun 1923: logit("%s", inst);
1.23 markus 1924:
1.278 markus 1925: if ((r = sshpkt_get_u32(ssh, &num_prompts)) != 0)
1926: goto out;
1.23 markus 1927: /*
1928: * Begin to build info response packet based on prompts requested.
1929: * We commit to providing the correct number of responses, so if
1930: * further on we run into a problem that prevents this, we have to
1931: * be sure and clean this up and send a correct error response.
1932: */
1.278 markus 1933: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_INFO_RESPONSE)) != 0 ||
1934: (r = sshpkt_put_u32(ssh, num_prompts)) != 0)
1935: goto out;
1.23 markus 1936:
1.335 djm 1937: debug2_f("num_prompts %d", num_prompts);
1.23 markus 1938: for (i = 0; i < num_prompts; i++) {
1.278 markus 1939: if ((r = sshpkt_get_cstring(ssh, &prompt, NULL)) != 0 ||
1940: (r = sshpkt_get_u8(ssh, &echo)) != 0)
1941: goto out;
1.336 djm 1942: if (asmprintf(&display_prompt, INT_MAX, NULL, "(%s@%s) %s",
1.335 djm 1943: authctxt->server_user, options.host_key_alias ?
1.336 djm 1944: options.host_key_alias : authctxt->host, prompt) == -1)
1945: fatal_f("asmprintf failed");
1.335 djm 1946: response = read_passphrase(display_prompt, echo ? RP_ECHO : 0);
1.278 markus 1947: if ((r = sshpkt_put_cstring(ssh, response)) != 0)
1948: goto out;
1949: freezero(response, strlen(response));
1.197 djm 1950: free(prompt);
1.335 djm 1951: free(display_prompt);
1952: display_prompt = response = prompt = NULL;
1.23 markus 1953: }
1.278 markus 1954: /* done with parsing incoming message. */
1955: if ((r = sshpkt_get_end(ssh)) != 0 ||
1956: (r = sshpkt_add_padding(ssh, 64)) != 0)
1957: goto out;
1958: r = sshpkt_send(ssh);
1959: out:
1960: if (response)
1961: freezero(response, strlen(response));
1962: free(prompt);
1.335 djm 1963: free(display_prompt);
1.278 markus 1964: free(name);
1965: free(inst);
1966: free(lang);
1967: return r;
1.68 markus 1968: }
1969:
1.100 markus 1970: static int
1.294 djm 1971: ssh_keysign(struct ssh *ssh, struct sshkey *key, u_char **sigp, size_t *lenp,
1.223 djm 1972: const u_char *data, size_t datalen)
1.100 markus 1973: {
1.223 djm 1974: struct sshbuf *b;
1.101 markus 1975: struct stat st;
1.100 markus 1976: pid_t pid;
1.304 deraadt 1977: int r, to[2], from[2], status;
1.295 djm 1978: int sock = ssh_packet_get_connection_in(ssh);
1.223 djm 1979: u_char rversion = 0, version = 2;
1980: void (*osigchld)(int);
1.100 markus 1981:
1.223 djm 1982: *sigp = NULL;
1983: *lenp = 0;
1.100 markus 1984:
1.306 deraadt 1985: if (stat(_PATH_SSH_KEY_SIGN, &st) == -1) {
1.331 djm 1986: error_f("not installed: %s", strerror(errno));
1.223 djm 1987: return -1;
1988: }
1989: if (fflush(stdout) != 0) {
1.331 djm 1990: error_f("fflush: %s", strerror(errno));
1.101 markus 1991: return -1;
1992: }
1.306 deraadt 1993: if (pipe(to) == -1) {
1.331 djm 1994: error_f("pipe: %s", strerror(errno));
1.100 markus 1995: return -1;
1996: }
1.306 deraadt 1997: if (pipe(from) == -1) {
1.331 djm 1998: error_f("pipe: %s", strerror(errno));
1.100 markus 1999: return -1;
2000: }
1.306 deraadt 2001: if ((pid = fork()) == -1) {
1.331 djm 2002: error_f("fork: %s", strerror(errno));
1.100 markus 2003: return -1;
2004: }
1.317 dtucker 2005: osigchld = ssh_signal(SIGCHLD, SIG_DFL);
1.100 markus 2006: if (pid == 0) {
2007: close(from[0]);
1.306 deraadt 2008: if (dup2(from[1], STDOUT_FILENO) == -1)
1.331 djm 2009: fatal_f("dup2: %s", strerror(errno));
1.100 markus 2010: close(to[1]);
1.306 deraadt 2011: if (dup2(to[0], STDIN_FILENO) == -1)
1.331 djm 2012: fatal_f("dup2: %s", strerror(errno));
1.103 markus 2013: close(from[1]);
2014: close(to[0]);
1.304 deraadt 2015:
1.306 deraadt 2016: if (dup2(sock, STDERR_FILENO + 1) == -1)
1.331 djm 2017: fatal_f("dup2: %s", strerror(errno));
1.304 deraadt 2018: sock = STDERR_FILENO + 1;
2019: fcntl(sock, F_SETFD, 0); /* keep the socket on exec */
1.223 djm 2020: closefrom(sock + 1);
1.304 deraadt 2021:
1.331 djm 2022: debug3_f("[child] pid=%ld, exec %s",
2023: (long)getpid(), _PATH_SSH_KEY_SIGN);
1.233 mmcc 2024: execl(_PATH_SSH_KEY_SIGN, _PATH_SSH_KEY_SIGN, (char *)NULL);
1.331 djm 2025: fatal_f("exec(%s): %s", _PATH_SSH_KEY_SIGN,
1.100 markus 2026: strerror(errno));
2027: }
2028: close(from[1]);
2029: close(to[0]);
1.305 djm 2030: sock = STDERR_FILENO + 1;
1.100 markus 2031:
1.223 djm 2032: if ((b = sshbuf_new()) == NULL)
1.331 djm 2033: fatal_f("sshbuf_new failed");
1.223 djm 2034: /* send # of sock, data to be signed */
1.253 djm 2035: if ((r = sshbuf_put_u32(b, sock)) != 0 ||
1.223 djm 2036: (r = sshbuf_put_string(b, data, datalen)) != 0)
1.331 djm 2037: fatal_fr(r, "buffer error");
1.223 djm 2038: if (ssh_msg_send(to[1], version, b) == -1)
1.331 djm 2039: fatal_f("couldn't send request");
1.223 djm 2040: sshbuf_reset(b);
2041: r = ssh_msg_recv(from[0], b);
1.101 markus 2042: close(from[0]);
2043: close(to[1]);
1.223 djm 2044: if (r < 0) {
1.331 djm 2045: error_f("no reply");
1.223 djm 2046: goto fail;
2047: }
1.101 markus 2048:
1.223 djm 2049: errno = 0;
1.306 deraadt 2050: while (waitpid(pid, &status, 0) == -1) {
1.223 djm 2051: if (errno != EINTR) {
1.331 djm 2052: error_f("waitpid %ld: %s", (long)pid, strerror(errno));
1.223 djm 2053: goto fail;
2054: }
2055: }
2056: if (!WIFEXITED(status)) {
1.331 djm 2057: error_f("exited abnormally");
1.223 djm 2058: goto fail;
2059: }
2060: if (WEXITSTATUS(status) != 0) {
1.331 djm 2061: error_f("exited with status %d", WEXITSTATUS(status));
1.223 djm 2062: goto fail;
2063: }
2064: if ((r = sshbuf_get_u8(b, &rversion)) != 0) {
1.331 djm 2065: error_fr(r, "buffer error");
1.223 djm 2066: goto fail;
2067: }
2068: if (rversion != version) {
1.331 djm 2069: error_f("bad version");
1.223 djm 2070: goto fail;
2071: }
2072: if ((r = sshbuf_get_string(b, sigp, lenp)) != 0) {
1.331 djm 2073: error_fr(r, "buffer error");
1.223 djm 2074: fail:
1.317 dtucker 2075: ssh_signal(SIGCHLD, osigchld);
1.223 djm 2076: sshbuf_free(b);
1.100 markus 2077: return -1;
2078: }
1.317 dtucker 2079: ssh_signal(SIGCHLD, osigchld);
1.223 djm 2080: sshbuf_free(b);
1.100 markus 2081:
2082: return 0;
2083: }
2084:
1.302 djm 2085: static int
1.295 djm 2086: userauth_hostbased(struct ssh *ssh)
1.68 markus 2087: {
1.295 djm 2088: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.223 djm 2089: struct sshkey *private = NULL;
2090: struct sshbuf *b = NULL;
2091: u_char *sig = NULL, *keyblob = NULL;
2092: char *fp = NULL, *chost = NULL, *lname = NULL;
2093: size_t siglen = 0, keylen = 0;
2094: int i, r, success = 0;
2095:
2096: if (authctxt->ktypes == NULL) {
1.344 dtucker 2097: authctxt->oktypes = xstrdup(options.hostbased_accepted_algos);
1.223 djm 2098: authctxt->ktypes = authctxt->oktypes;
2099: }
1.213 djm 2100:
1.223 djm 2101: /*
1.344 dtucker 2102: * Work through each listed type pattern in HostbasedAcceptedAlgorithms,
1.223 djm 2103: * trying each hostkey that matches the type in turn.
2104: */
2105: for (;;) {
2106: if (authctxt->active_ktype == NULL)
2107: authctxt->active_ktype = strsep(&authctxt->ktypes, ",");
2108: if (authctxt->active_ktype == NULL ||
2109: *authctxt->active_ktype == '\0')
2110: break;
1.331 djm 2111: debug3_f("trying key type %s", authctxt->active_ktype);
1.68 markus 2112:
1.223 djm 2113: /* check for a useful key */
2114: private = NULL;
2115: for (i = 0; i < authctxt->sensitive->nkeys; i++) {
2116: if (authctxt->sensitive->keys[i] == NULL ||
2117: authctxt->sensitive->keys[i]->type == KEY_UNSPEC)
2118: continue;
2119: if (match_pattern_list(
2120: sshkey_ssh_name(authctxt->sensitive->keys[i]),
1.224 djm 2121: authctxt->active_ktype, 0) != 1)
1.223 djm 2122: continue;
1.68 markus 2123: /* we take and free the key */
1.223 djm 2124: private = authctxt->sensitive->keys[i];
2125: authctxt->sensitive->keys[i] = NULL;
1.68 markus 2126: break;
2127: }
1.223 djm 2128: /* Found one */
2129: if (private != NULL)
2130: break;
2131: /* No more keys of this type; advance */
2132: authctxt->active_ktype = NULL;
1.68 markus 2133: }
1.223 djm 2134: if (private == NULL) {
2135: free(authctxt->oktypes);
2136: authctxt->oktypes = authctxt->ktypes = NULL;
2137: authctxt->active_ktype = NULL;
1.109 markus 2138: debug("No more client hostkeys for hostbased authentication.");
1.223 djm 2139: goto out;
1.68 markus 2140: }
1.211 djm 2141:
1.223 djm 2142: if ((fp = sshkey_fingerprint(private, options.fingerprint_hash,
2143: SSH_FP_DEFAULT)) == NULL) {
1.331 djm 2144: error_f("sshkey_fingerprint failed");
1.223 djm 2145: goto out;
1.68 markus 2146: }
1.331 djm 2147: debug_f("trying hostkey %s %s", sshkey_ssh_name(private), fp);
1.211 djm 2148:
1.84 markus 2149: /* figure out a name for the client host */
1.295 djm 2150: lname = get_local_name(ssh_packet_get_connection_in(ssh));
2151: if (lname == NULL) {
1.331 djm 2152: error_f("cannot get local ipaddr/name");
1.223 djm 2153: goto out;
1.84 markus 2154: }
1.223 djm 2155:
2156: /* XXX sshbuf_put_stringf? */
2157: xasprintf(&chost, "%s.", lname);
1.331 djm 2158: debug2_f("chost %s", chost);
1.84 markus 2159:
1.68 markus 2160: /* construct data */
1.223 djm 2161: if ((b = sshbuf_new()) == NULL) {
1.331 djm 2162: error_f("sshbuf_new failed");
1.223 djm 2163: goto out;
2164: }
2165: if ((r = sshkey_to_blob(private, &keyblob, &keylen)) != 0) {
1.331 djm 2166: error_fr(r, "sshkey_to_blob");
1.223 djm 2167: goto out;
2168: }
1.346 djm 2169: if ((r = sshbuf_put_stringb(b, ssh->kex->session_id)) != 0 ||
1.223 djm 2170: (r = sshbuf_put_u8(b, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
2171: (r = sshbuf_put_cstring(b, authctxt->server_user)) != 0 ||
1.267 djm 2172: (r = sshbuf_put_cstring(b, authctxt->service)) != 0 ||
1.223 djm 2173: (r = sshbuf_put_cstring(b, authctxt->method->name)) != 0 ||
1.343 djm 2174: (r = sshbuf_put_cstring(b, authctxt->active_ktype)) != 0 ||
1.223 djm 2175: (r = sshbuf_put_string(b, keyblob, keylen)) != 0 ||
2176: (r = sshbuf_put_cstring(b, chost)) != 0 ||
2177: (r = sshbuf_put_cstring(b, authctxt->local_user)) != 0) {
1.331 djm 2178: error_fr(r, "buffer error");
1.223 djm 2179: goto out;
2180: }
2181:
1.68 markus 2182: #ifdef DEBUG_PK
1.223 djm 2183: sshbuf_dump(b, stderr);
1.68 markus 2184: #endif
1.294 djm 2185: if ((r = ssh_keysign(ssh, private, &sig, &siglen,
2186: sshbuf_ptr(b), sshbuf_len(b))) != 0) {
1.223 djm 2187: error("sign using hostkey %s %s failed",
2188: sshkey_ssh_name(private), fp);
2189: goto out;
2190: }
2191: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
2192: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
2193: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
2194: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1.343 djm 2195: (r = sshpkt_put_cstring(ssh, authctxt->active_ktype)) != 0 ||
1.223 djm 2196: (r = sshpkt_put_string(ssh, keyblob, keylen)) != 0 ||
2197: (r = sshpkt_put_cstring(ssh, chost)) != 0 ||
2198: (r = sshpkt_put_cstring(ssh, authctxt->local_user)) != 0 ||
2199: (r = sshpkt_put_string(ssh, sig, siglen)) != 0 ||
2200: (r = sshpkt_send(ssh)) != 0) {
1.331 djm 2201: error_fr(r, "packet error");
1.223 djm 2202: goto out;
2203: }
2204: success = 1;
2205:
2206: out:
1.278 markus 2207: if (sig != NULL)
2208: freezero(sig, siglen);
1.223 djm 2209: free(keyblob);
2210: free(lname);
2211: free(fp);
1.197 djm 2212: free(chost);
1.223 djm 2213: sshkey_free(private);
2214: sshbuf_free(b);
1.68 markus 2215:
1.223 djm 2216: return success;
1.23 markus 2217: }
1.170 djm 2218:
1.20 markus 2219: /* find auth method */
2220:
2221: /*
2222: * given auth method name, if configurable options permit this method fill
2223: * in auth_ident field and return true, otherwise return false.
2224: */
1.76 itojun 2225: static int
1.20 markus 2226: authmethod_is_enabled(Authmethod *method)
2227: {
2228: if (method == NULL)
2229: return 0;
2230: /* return false if options indicate this method is disabled */
2231: if (method->enabled == NULL || *method->enabled == 0)
2232: return 0;
2233: /* return false if batch mode is enabled but method needs interactive mode */
2234: if (method->batch_flag != NULL && *method->batch_flag != 0)
2235: return 0;
2236: return 1;
2237: }
2238:
1.76 itojun 2239: static Authmethod *
1.20 markus 2240: authmethod_lookup(const char *name)
1.1 markus 2241: {
1.20 markus 2242: Authmethod *method = NULL;
2243: if (name != NULL)
2244: for (method = authmethods; method->name != NULL; method++)
2245: if (strcmp(name, method->name) == 0)
2246: return method;
2247: debug2("Unrecognized authentication method name: %s", name ? name : "NULL");
2248: return NULL;
2249: }
1.1 markus 2250:
1.53 markus 2251: /* XXX internal state */
2252: static Authmethod *current = NULL;
2253: static char *supported = NULL;
2254: static char *preferred = NULL;
1.105 deraadt 2255:
1.20 markus 2256: /*
2257: * Given the authentication method list sent by the server, return the
2258: * next method we should try. If the server initially sends a nil list,
1.67 markus 2259: * use a built-in default list.
1.41 stevesk 2260: */
1.76 itojun 2261: static Authmethod *
1.20 markus 2262: authmethod_get(char *authlist)
2263: {
1.53 markus 2264: char *name = NULL;
1.97 markus 2265: u_int next;
1.41 stevesk 2266:
1.20 markus 2267: /* Use a suitable default if we're passed a nil list. */
2268: if (authlist == NULL || strlen(authlist) == 0)
1.53 markus 2269: authlist = options.preferred_authentications;
1.20 markus 2270:
1.53 markus 2271: if (supported == NULL || strcmp(authlist, supported) != 0) {
2272: debug3("start over, passed a different list %s", authlist);
1.197 djm 2273: free(supported);
1.53 markus 2274: supported = xstrdup(authlist);
2275: preferred = options.preferred_authentications;
2276: debug3("preferred %s", preferred);
2277: current = NULL;
2278: } else if (current != NULL && authmethod_is_enabled(current))
2279: return current;
1.20 markus 2280:
1.53 markus 2281: for (;;) {
2282: if ((name = match_list(preferred, supported, &next)) == NULL) {
1.109 markus 2283: debug("No more authentication methods to try.");
1.53 markus 2284: current = NULL;
2285: return NULL;
2286: }
2287: preferred += next;
1.23 markus 2288: debug3("authmethod_lookup %s", name);
1.53 markus 2289: debug3("remaining preferred: %s", preferred);
2290: if ((current = authmethod_lookup(name)) != NULL &&
2291: authmethod_is_enabled(current)) {
1.23 markus 2292: debug3("authmethod_is_enabled %s", name);
1.109 markus 2293: debug("Next authentication method: %s", name);
1.197 djm 2294: free(name);
1.53 markus 2295: return current;
1.23 markus 2296: }
1.198 dtucker 2297: free(name);
1.1 markus 2298: }
1.53 markus 2299: }
1.1 markus 2300:
1.79 stevesk 2301: static char *
1.53 markus 2302: authmethods_get(void)
2303: {
2304: Authmethod *method = NULL;
1.278 markus 2305: struct sshbuf *b;
1.93 markus 2306: char *list;
1.278 markus 2307: int r;
1.27 provos 2308:
1.278 markus 2309: if ((b = sshbuf_new()) == NULL)
1.331 djm 2310: fatal_f("sshbuf_new failed");
1.53 markus 2311: for (method = authmethods; method->name != NULL; method++) {
2312: if (authmethod_is_enabled(method)) {
1.278 markus 2313: if ((r = sshbuf_putf(b, "%s%s",
2314: sshbuf_len(b) ? "," : "", method->name)) != 0)
1.331 djm 2315: fatal_fr(r, "buffer error");
1.53 markus 2316: }
2317: }
1.278 markus 2318: if ((list = sshbuf_dup_string(b)) == NULL)
1.331 djm 2319: fatal_f("sshbuf_dup_string failed");
1.278 markus 2320: sshbuf_free(b);
1.93 markus 2321: return list;
1.1 markus 2322: }