Annotation of src/usr.bin/ssh/sshconnect2.c, Revision 1.351
1.351 ! djm 1: /* $OpenBSD: sshconnect2.c,v 1.350 2021/07/02 05:11:21 dtucker 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.");
1.351 ! djm 483: if (ssh_packet_connection_is_on_socket(ssh)) {
! 484: verbose("Authenticated to %s ([%s]:%d) using \"%s\".", host,
! 485: ssh_remote_ipaddr(ssh), ssh_remote_port(ssh),
! 486: authctxt.method->name);
! 487: } else {
! 488: verbose("Authenticated to %s (via proxy) using \"%s\".", host,
! 489: authctxt.method->name);
! 490: }
1.20 markus 491: }
1.119 markus 492:
1.231 markus 493: /* ARGSUSED */
1.302 djm 494: static int
1.261 markus 495: input_userauth_service_accept(int type, u_int32_t seq, struct ssh *ssh)
1.231 markus 496: {
497: int r;
498:
499: if (ssh_packet_remaining(ssh) > 0) {
500: char *reply;
501:
502: if ((r = sshpkt_get_cstring(ssh, &reply, NULL)) != 0)
503: goto out;
504: debug2("service_accept: %s", reply);
505: free(reply);
506: } else {
507: debug2("buggy server: service_accept w/o service");
508: }
509: if ((r = sshpkt_get_end(ssh)) != 0)
510: goto out;
511: debug("SSH2_MSG_SERVICE_ACCEPT received");
512:
513: /* initial userauth request */
1.295 djm 514: userauth_none(ssh);
1.231 markus 515:
516: ssh_dispatch_set(ssh, SSH2_MSG_EXT_INFO, &input_userauth_error);
517: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_SUCCESS, &input_userauth_success);
518: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_FAILURE, &input_userauth_failure);
519: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_BANNER, &input_userauth_banner);
520: r = 0;
521: out:
522: return r;
523: }
524:
525: /* ARGSUSED */
1.302 djm 526: static int
1.261 markus 527: input_userauth_ext_info(int type, u_int32_t seqnr, struct ssh *ssh)
1.231 markus 528: {
1.261 markus 529: return kex_input_ext_info(type, seqnr, ssh);
1.231 markus 530: }
531:
1.20 markus 532: void
1.295 djm 533: userauth(struct ssh *ssh, char *authlist)
1.51 markus 534: {
1.295 djm 535: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.278 markus 536:
1.170 djm 537: if (authctxt->method != NULL && authctxt->method->cleanup != NULL)
1.295 djm 538: authctxt->method->cleanup(ssh);
1.170 djm 539:
1.197 djm 540: free(authctxt->methoddata);
541: authctxt->methoddata = NULL;
1.51 markus 542: if (authlist == NULL) {
543: authlist = authctxt->authlist;
544: } else {
1.197 djm 545: free(authctxt->authlist);
1.51 markus 546: authctxt->authlist = authlist;
547: }
548: for (;;) {
549: Authmethod *method = authmethod_get(authlist);
550: if (method == NULL)
1.264 dtucker 551: fatal("%s@%s: Permission denied (%s).",
552: authctxt->server_user, authctxt->host, authlist);
1.51 markus 553: authctxt->method = method;
1.119 markus 554:
555: /* reset the per method handler */
1.278 markus 556: ssh_dispatch_range(ssh, SSH2_MSG_USERAUTH_PER_METHOD_MIN,
1.119 markus 557: SSH2_MSG_USERAUTH_PER_METHOD_MAX, NULL);
558:
559: /* and try new method */
1.295 djm 560: if (method->userauth(ssh) != 0) {
1.51 markus 561: debug2("we sent a %s packet, wait for reply", method->name);
562: break;
563: } else {
564: debug2("we did not send a packet, disable method");
565: method->enabled = NULL;
566: }
567: }
568: }
1.105 deraadt 569:
1.169 djm 570: /* ARGSUSED */
1.302 djm 571: static int
1.261 markus 572: input_userauth_error(int type, u_int32_t seq, struct ssh *ssh)
1.20 markus 573: {
1.331 djm 574: fatal_f("bad message during authentication: type %d", type);
1.218 markus 575: return 0;
1.35 markus 576: }
1.105 deraadt 577:
1.169 djm 578: /* ARGSUSED */
1.302 djm 579: static int
1.261 markus 580: input_userauth_banner(int type, u_int32_t seq, struct ssh *ssh)
1.35 markus 581: {
1.295 djm 582: char *msg = NULL;
1.294 djm 583: size_t len;
584: int r;
1.126 deraadt 585:
1.331 djm 586: debug3_f("entering");
1.294 djm 587: if ((r = sshpkt_get_cstring(ssh, &msg, &len)) != 0 ||
1.295 djm 588: (r = sshpkt_get_cstring(ssh, NULL, NULL)) != 0)
1.294 djm 589: goto out;
1.246 djm 590: if (len > 0 && options.log_level >= SYSLOG_LEVEL_INFO)
591: fmprintf(stderr, "%s", msg);
1.294 djm 592: r = 0;
593: out:
1.246 djm 594: free(msg);
1.294 djm 595: return r;
1.20 markus 596: }
1.105 deraadt 597:
1.169 djm 598: /* ARGSUSED */
1.302 djm 599: static int
1.261 markus 600: input_userauth_success(int type, u_int32_t seq, struct ssh *ssh)
1.20 markus 601: {
1.260 markus 602: Authctxt *authctxt = ssh->authctxt;
1.172 djm 603:
1.20 markus 604: if (authctxt == NULL)
1.331 djm 605: fatal_f("no authentication context");
1.197 djm 606: free(authctxt->authlist);
607: authctxt->authlist = NULL;
1.172 djm 608: if (authctxt->method != NULL && authctxt->method->cleanup != NULL)
1.295 djm 609: authctxt->method->cleanup(ssh);
1.197 djm 610: free(authctxt->methoddata);
611: authctxt->methoddata = NULL;
1.20 markus 612: authctxt->success = 1; /* break out */
1.218 markus 613: return 0;
1.20 markus 614: }
1.105 deraadt 615:
1.302 djm 616: #if 0
617: static int
1.261 markus 618: input_userauth_success_unexpected(int type, u_int32_t seq, struct ssh *ssh)
1.172 djm 619: {
1.260 markus 620: Authctxt *authctxt = ssh->authctxt;
1.172 djm 621:
622: if (authctxt == NULL)
1.331 djm 623: fatal_f("no authentication context");
1.172 djm 624:
625: fatal("Unexpected authentication success during %s.",
626: authctxt->method->name);
1.218 markus 627: return 0;
1.172 djm 628: }
1.302 djm 629: #endif
1.172 djm 630:
1.169 djm 631: /* ARGSUSED */
1.302 djm 632: static int
1.261 markus 633: input_userauth_failure(int type, u_int32_t seq, struct ssh *ssh)
1.20 markus 634: {
1.260 markus 635: Authctxt *authctxt = ssh->authctxt;
1.20 markus 636: char *authlist = NULL;
1.278 markus 637: u_char partial;
1.20 markus 638:
639: if (authctxt == NULL)
640: fatal("input_userauth_failure: no authentication context");
641:
1.307 dtucker 642: if (sshpkt_get_cstring(ssh, &authlist, NULL) != 0 ||
643: sshpkt_get_u8(ssh, &partial) != 0 ||
644: sshpkt_get_end(ssh) != 0)
1.278 markus 645: goto out;
1.20 markus 646:
1.193 markus 647: if (partial != 0) {
1.351 ! djm 648: verbose("Authenticated using \"%s\" with partial success.",
! 649: authctxt->method->name);
1.193 markus 650: /* reset state */
1.251 djm 651: pubkey_reset(authctxt);
1.193 markus 652: }
1.109 markus 653: debug("Authentications that can continue: %s", authlist);
1.20 markus 654:
1.295 djm 655: userauth(ssh, authlist);
1.278 markus 656: authlist = NULL;
657: out:
658: free(authlist);
1.218 markus 659: return 0;
1.51 markus 660: }
1.169 djm 661:
1.287 djm 662: /*
663: * Format an identity for logging including filename, key type, fingerprint
664: * and location (agent, etc.). Caller must free.
665: */
666: static char *
667: format_identity(Identity *id)
668: {
669: char *fp = NULL, *ret = NULL;
1.309 djm 670: const char *note = "";
1.287 djm 671:
672: if (id->key != NULL) {
1.347 djm 673: fp = sshkey_fingerprint(id->key, options.fingerprint_hash,
1.287 djm 674: SSH_FP_DEFAULT);
675: }
1.309 djm 676: if (id->key) {
677: if ((id->key->flags & SSHKEY_FLAG_EXT) != 0)
678: note = " token";
1.311 markus 679: else if (sshkey_is_sk(id->key))
1.319 naddy 680: note = " authenticator";
1.309 djm 681: }
1.287 djm 682: xasprintf(&ret, "%s %s%s%s%s%s%s",
683: id->filename,
684: id->key ? sshkey_type(id->key) : "", id->key ? " " : "",
685: fp ? fp : "",
1.309 djm 686: id->userprovided ? " explicit" : "", note,
1.287 djm 687: id->agent_fd != -1 ? " agent" : "");
688: free(fp);
689: return ret;
690: }
691:
1.169 djm 692: /* ARGSUSED */
1.302 djm 693: static int
1.261 markus 694: input_userauth_pk_ok(int type, u_int32_t seq, struct ssh *ssh)
1.51 markus 695: {
1.260 markus 696: Authctxt *authctxt = ssh->authctxt;
1.259 markus 697: struct sshkey *key = NULL;
1.117 markus 698: Identity *id = NULL;
1.287 djm 699: int pktype, found = 0, sent = 0;
1.278 markus 700: size_t blen;
1.287 djm 701: char *pkalg = NULL, *fp = NULL, *ident = NULL;
1.278 markus 702: u_char *pkblob = NULL;
703: int r;
1.51 markus 704:
705: if (authctxt == NULL)
706: fatal("input_userauth_pk_ok: no authentication context");
1.267 djm 707:
1.278 markus 708: if ((r = sshpkt_get_cstring(ssh, &pkalg, NULL)) != 0 ||
709: (r = sshpkt_get_string(ssh, &pkblob, &blen)) != 0 ||
710: (r = sshpkt_get_end(ssh)) != 0)
711: goto done;
1.51 markus 712:
1.278 markus 713: if ((pktype = sshkey_type_from_name(pkalg)) == KEY_UNSPEC) {
1.331 djm 714: debug_f("server sent unknown pkalg %s", pkalg);
1.117 markus 715: goto done;
716: }
1.278 markus 717: if ((r = sshkey_from_blob(pkblob, blen, &key)) != 0) {
1.331 djm 718: debug_r(r, "no key from blob. pkalg %s", pkalg);
1.117 markus 719: goto done;
720: }
721: if (key->type != pktype) {
722: error("input_userauth_pk_ok: type mismatch "
723: "for decoded key (received %d, expected %d)",
724: key->type, pktype);
725: goto done;
726: }
727:
1.127 markus 728: /*
729: * search keys in the reverse order, because last candidate has been
730: * moved to the end of the queue. this also avoids confusion by
731: * duplicate keys
732: */
1.136 henning 733: TAILQ_FOREACH_REVERSE(id, &authctxt->keys, idlist, next) {
1.278 markus 734: if (sshkey_equal(key, id->key)) {
1.287 djm 735: found = 1;
1.51 markus 736: break;
737: }
1.117 markus 738: }
1.287 djm 739: if (!found || id == NULL) {
740: fp = sshkey_fingerprint(key, options.fingerprint_hash,
741: SSH_FP_DEFAULT);
1.331 djm 742: error_f("server replied with unknown key: %s %s",
1.287 djm 743: sshkey_type(key), fp == NULL ? "<ERROR>" : fp);
744: goto done;
745: }
746: ident = format_identity(id);
747: debug("Server accepts key: %s", ident);
1.295 djm 748: sent = sign_and_send_pubkey(ssh, id);
1.278 markus 749: r = 0;
750: done:
751: sshkey_free(key);
1.287 djm 752: free(ident);
753: free(fp);
1.197 djm 754: free(pkalg);
755: free(pkblob);
1.51 markus 756:
1.106 deraadt 757: /* try another method if we did not send a packet */
1.278 markus 758: if (r == 0 && sent == 0)
1.295 djm 759: userauth(ssh, NULL);
1.278 markus 760: return r;
1.20 markus 761: }
1.121 markus 762:
763: #ifdef GSSAPI
1.302 djm 764: static int
1.295 djm 765: userauth_gssapi(struct ssh *ssh)
1.121 markus 766: {
1.295 djm 767: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.121 markus 768: Gssctxt *gssctxt = NULL;
769: OM_uint32 min;
1.278 markus 770: int r, ok = 0;
1.302 djm 771: gss_OID mech = NULL;
1.121 markus 772:
773: /* Try one GSSAPI method at a time, rather than sending them all at
774: * once. */
775:
1.302 djm 776: if (authctxt->gss_supported_mechs == NULL)
777: gss_indicate_mechs(&min, &authctxt->gss_supported_mechs);
1.121 markus 778:
1.302 djm 779: /* Check to see whether the mechanism is usable before we offer it */
780: while (authctxt->mech_tried < authctxt->gss_supported_mechs->count &&
781: !ok) {
782: mech = &authctxt->gss_supported_mechs->
783: elements[authctxt->mech_tried];
1.121 markus 784: /* My DER encoding requires length<128 */
1.302 djm 785: if (mech->length < 128 && ssh_gssapi_check_mechanism(&gssctxt,
786: mech, authctxt->host)) {
1.121 markus 787: ok = 1; /* Mechanism works */
788: } else {
1.302 djm 789: authctxt->mech_tried++;
1.121 markus 790: }
791: }
792:
1.302 djm 793: if (!ok || mech == NULL)
1.139 djm 794: return 0;
1.121 markus 795:
796: authctxt->methoddata=(void *)gssctxt;
797:
1.278 markus 798: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
799: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
800: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
801: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
802: (r = sshpkt_put_u32(ssh, 1)) != 0 ||
1.302 djm 803: (r = sshpkt_put_u32(ssh, (mech->length) + 2)) != 0 ||
1.278 markus 804: (r = sshpkt_put_u8(ssh, SSH_GSS_OIDTYPE)) != 0 ||
1.302 djm 805: (r = sshpkt_put_u8(ssh, mech->length)) != 0 ||
806: (r = sshpkt_put(ssh, mech->elements, mech->length)) != 0 ||
1.278 markus 807: (r = sshpkt_send(ssh)) != 0)
1.331 djm 808: fatal_fr(r, "send packet");
1.278 markus 809:
810: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_RESPONSE, &input_gssapi_response);
811: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_TOKEN, &input_gssapi_token);
812: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_ERROR, &input_gssapi_error);
813: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_ERRTOK, &input_gssapi_errtok);
1.121 markus 814:
1.302 djm 815: authctxt->mech_tried++; /* Move along to next candidate */
1.121 markus 816:
817: return 1;
818: }
819:
1.302 djm 820: static void
821: userauth_gssapi_cleanup(struct ssh *ssh)
822: {
823: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
824: Gssctxt *gssctxt = (Gssctxt *)authctxt->methoddata;
825:
826: ssh_gssapi_delete_ctx(&gssctxt);
827: authctxt->methoddata = NULL;
828:
829: free(authctxt->gss_supported_mechs);
830: authctxt->gss_supported_mechs = NULL;
831: }
832:
1.130 markus 833: static OM_uint32
1.262 djm 834: process_gssapi_token(struct ssh *ssh, gss_buffer_t recv_tok)
1.130 markus 835: {
1.260 markus 836: Authctxt *authctxt = ssh->authctxt;
1.130 markus 837: Gssctxt *gssctxt = authctxt->methoddata;
838: gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
1.142 djm 839: gss_buffer_desc mic = GSS_C_EMPTY_BUFFER;
840: gss_buffer_desc gssbuf;
1.132 markus 841: OM_uint32 status, ms, flags;
1.278 markus 842: int r;
1.133 djm 843:
1.130 markus 844: status = ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
1.132 markus 845: recv_tok, &send_tok, &flags);
1.130 markus 846:
847: if (send_tok.length > 0) {
1.278 markus 848: u_char type = GSS_ERROR(status) ?
849: SSH2_MSG_USERAUTH_GSSAPI_ERRTOK :
850: SSH2_MSG_USERAUTH_GSSAPI_TOKEN;
851:
852: if ((r = sshpkt_start(ssh, type)) != 0 ||
853: (r = sshpkt_put_string(ssh, send_tok.value,
854: send_tok.length)) != 0 ||
855: (r = sshpkt_send(ssh)) != 0)
1.331 djm 856: fatal_fr(r, "send %u packet", type);
1.133 djm 857:
1.130 markus 858: gss_release_buffer(&ms, &send_tok);
859: }
1.133 djm 860:
1.130 markus 861: if (status == GSS_S_COMPLETE) {
1.132 markus 862: /* send either complete or MIC, depending on mechanism */
863: if (!(flags & GSS_C_INTEG_FLAG)) {
1.278 markus 864: if ((r = sshpkt_start(ssh,
865: SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE)) != 0 ||
866: (r = sshpkt_send(ssh)) != 0)
1.331 djm 867: fatal_fr(r, "send completion");
1.132 markus 868: } else {
1.278 markus 869: struct sshbuf *b;
870:
871: if ((b = sshbuf_new()) == NULL)
1.331 djm 872: fatal_f("sshbuf_new failed");
1.278 markus 873: ssh_gssapi_buildmic(b, authctxt->server_user,
1.346 djm 874: authctxt->service, "gssapi-with-mic",
875: ssh->kex->session_id);
1.132 markus 876:
1.278 markus 877: if ((gssbuf.value = sshbuf_mutable_ptr(b)) == NULL)
1.331 djm 878: fatal_f("sshbuf_mutable_ptr failed");
1.278 markus 879: gssbuf.length = sshbuf_len(b);
1.133 djm 880:
1.132 markus 881: status = ssh_gssapi_sign(gssctxt, &gssbuf, &mic);
1.133 djm 882:
1.132 markus 883: if (!GSS_ERROR(status)) {
1.278 markus 884: if ((r = sshpkt_start(ssh,
885: SSH2_MSG_USERAUTH_GSSAPI_MIC)) != 0 ||
886: (r = sshpkt_put_string(ssh, mic.value,
887: mic.length)) != 0 ||
888: (r = sshpkt_send(ssh)) != 0)
1.331 djm 889: fatal_fr(r, "send MIC");
1.132 markus 890: }
1.133 djm 891:
1.278 markus 892: sshbuf_free(b);
1.132 markus 893: gss_release_buffer(&ms, &mic);
1.133 djm 894: }
1.130 markus 895: }
1.133 djm 896:
1.130 markus 897: return status;
898: }
899:
1.169 djm 900: /* ARGSUSED */
1.302 djm 901: static int
1.261 markus 902: input_gssapi_response(int type, u_int32_t plen, struct ssh *ssh)
1.121 markus 903: {
1.260 markus 904: Authctxt *authctxt = ssh->authctxt;
1.121 markus 905: Gssctxt *gssctxt;
1.278 markus 906: size_t oidlen;
907: u_char *oidv = NULL;
908: int r;
1.121 markus 909:
910: if (authctxt == NULL)
911: fatal("input_gssapi_response: no authentication context");
912: gssctxt = authctxt->methoddata;
913:
914: /* Setup our OID */
1.278 markus 915: if ((r = sshpkt_get_string(ssh, &oidv, &oidlen)) != 0)
916: goto done;
1.121 markus 917:
1.129 markus 918: if (oidlen <= 2 ||
919: oidv[0] != SSH_GSS_OIDTYPE ||
920: oidv[1] != oidlen - 2) {
921: debug("Badly encoded mechanism OID received");
1.296 djm 922: userauth(ssh, NULL);
1.278 markus 923: goto ok;
1.121 markus 924: }
1.129 markus 925:
926: if (!ssh_gssapi_check_oid(gssctxt, oidv + 2, oidlen - 2))
927: fatal("Server returned different OID than expected");
1.121 markus 928:
1.278 markus 929: if ((r = sshpkt_get_end(ssh)) != 0)
930: goto done;
1.121 markus 931:
1.262 djm 932: if (GSS_ERROR(process_gssapi_token(ssh, GSS_C_NO_BUFFER))) {
1.121 markus 933: /* Start again with next method on list */
934: debug("Trying to start again");
1.296 djm 935: userauth(ssh, NULL);
1.278 markus 936: goto ok;
1.121 markus 937: }
1.278 markus 938: ok:
939: r = 0;
940: done:
941: free(oidv);
942: return r;
1.121 markus 943: }
944:
1.169 djm 945: /* ARGSUSED */
1.302 djm 946: static int
1.261 markus 947: input_gssapi_token(int type, u_int32_t plen, struct ssh *ssh)
1.121 markus 948: {
1.260 markus 949: Authctxt *authctxt = ssh->authctxt;
1.121 markus 950: gss_buffer_desc recv_tok;
1.278 markus 951: u_char *p = NULL;
952: size_t len;
1.130 markus 953: OM_uint32 status;
1.278 markus 954: int r;
1.121 markus 955:
956: if (authctxt == NULL)
957: fatal("input_gssapi_response: no authentication context");
958:
1.278 markus 959: if ((r = sshpkt_get_string(ssh, &p, &len)) != 0 ||
960: (r = sshpkt_get_end(ssh)) != 0)
961: goto out;
1.121 markus 962:
1.278 markus 963: recv_tok.value = p;
964: recv_tok.length = len;
1.262 djm 965: status = process_gssapi_token(ssh, &recv_tok);
1.121 markus 966:
1.278 markus 967: /* Start again with the next method in the list */
1.121 markus 968: if (GSS_ERROR(status)) {
1.296 djm 969: userauth(ssh, NULL);
1.278 markus 970: /* ok */
1.121 markus 971: }
1.278 markus 972: r = 0;
973: out:
974: free(p);
975: return r;
1.121 markus 976: }
977:
1.169 djm 978: /* ARGSUSED */
1.302 djm 979: static int
1.261 markus 980: input_gssapi_errtok(int type, u_int32_t plen, struct ssh *ssh)
1.121 markus 981: {
1.260 markus 982: Authctxt *authctxt = ssh->authctxt;
1.121 markus 983: Gssctxt *gssctxt;
984: gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
985: gss_buffer_desc recv_tok;
1.194 djm 986: OM_uint32 ms;
1.278 markus 987: u_char *p = NULL;
988: size_t len;
989: int r;
1.121 markus 990:
991: if (authctxt == NULL)
992: fatal("input_gssapi_response: no authentication context");
993: gssctxt = authctxt->methoddata;
994:
1.278 markus 995: if ((r = sshpkt_get_string(ssh, &p, &len)) != 0 ||
996: (r = sshpkt_get_end(ssh)) != 0) {
997: free(p);
998: return r;
999: }
1.121 markus 1000:
1001: /* Stick it into GSSAPI and see what it says */
1.278 markus 1002: recv_tok.value = p;
1003: recv_tok.length = len;
1.194 djm 1004: (void)ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
1.140 djm 1005: &recv_tok, &send_tok, NULL);
1.278 markus 1006: free(p);
1.121 markus 1007: gss_release_buffer(&ms, &send_tok);
1008:
1009: /* Server will be returning a failed packet after this one */
1.220 djm 1010: return 0;
1.121 markus 1011: }
1012:
1.169 djm 1013: /* ARGSUSED */
1.302 djm 1014: static int
1.261 markus 1015: input_gssapi_error(int type, u_int32_t plen, struct ssh *ssh)
1.121 markus 1016: {
1.278 markus 1017: char *msg = NULL;
1018: char *lang = NULL;
1019: int r;
1.121 markus 1020:
1.278 markus 1021: if ((r = sshpkt_get_u32(ssh, NULL)) != 0 || /* maj */
1022: (r = sshpkt_get_u32(ssh, NULL)) != 0 || /* min */
1023: (r = sshpkt_get_cstring(ssh, &msg, NULL)) != 0 ||
1024: (r = sshpkt_get_cstring(ssh, &lang, NULL)) != 0)
1025: goto out;
1026: r = sshpkt_get_end(ssh);
1.143 stevesk 1027: debug("Server GSSAPI Error:\n%s", msg);
1.278 markus 1028: out:
1.197 djm 1029: free(msg);
1030: free(lang);
1.278 markus 1031: return r;
1.121 markus 1032: }
1033: #endif /* GSSAPI */
1.20 markus 1034:
1.302 djm 1035: static int
1.295 djm 1036: userauth_none(struct ssh *ssh)
1.23 markus 1037: {
1.295 djm 1038: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.278 markus 1039: int r;
1040:
1.23 markus 1041: /* initial userauth request */
1.278 markus 1042: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1043: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1044: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1045: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1046: (r = sshpkt_send(ssh)) != 0)
1.331 djm 1047: fatal_fr(r, "send packet");
1.23 markus 1048: return 1;
1049: }
1050:
1.302 djm 1051: static int
1.295 djm 1052: userauth_passwd(struct ssh *ssh)
1.1 markus 1053: {
1.295 djm 1054: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.290 djm 1055: char *password, *prompt = NULL;
1.175 dtucker 1056: const char *host = options.host_key_alias ? options.host_key_alias :
1057: authctxt->host;
1.278 markus 1058: int r;
1.6 markus 1059:
1.292 djm 1060: if (authctxt->attempt_passwd++ >= options.number_of_password_prompts)
1.6 markus 1061: return 0;
1.13 todd 1062:
1.292 djm 1063: if (authctxt->attempt_passwd != 1)
1.13 todd 1064: error("Permission denied, please try again.");
1.1 markus 1065:
1.290 djm 1066: xasprintf(&prompt, "%s@%s's password: ", authctxt->server_user, host);
1.1 markus 1067: password = read_passphrase(prompt, 0);
1.278 markus 1068: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1069: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1070: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1071: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1072: (r = sshpkt_put_u8(ssh, 0)) != 0 ||
1073: (r = sshpkt_put_cstring(ssh, password)) != 0 ||
1074: (r = sshpkt_add_padding(ssh, 64)) != 0 ||
1075: (r = sshpkt_send(ssh)) != 0)
1.331 djm 1076: fatal_fr(r, "send packet");
1.99 markus 1077:
1.290 djm 1078: free(prompt);
1079: if (password != NULL)
1.278 markus 1080: freezero(password, strlen(password));
1081:
1082: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
1.99 markus 1083: &input_userauth_passwd_changereq);
1084:
1.1 markus 1085: return 1;
1086: }
1.169 djm 1087:
1.99 markus 1088: /*
1089: * parse PASSWD_CHANGEREQ, prompt user and send SSH2_MSG_USERAUTH_REQUEST
1090: */
1.169 djm 1091: /* ARGSUSED */
1.302 djm 1092: static int
1.261 markus 1093: input_userauth_passwd_changereq(int type, u_int32_t seqnr, struct ssh *ssh)
1.99 markus 1094: {
1.260 markus 1095: Authctxt *authctxt = ssh->authctxt;
1.278 markus 1096: char *info = NULL, *lang = NULL, *password = NULL, *retype = NULL;
1.266 dtucker 1097: char prompt[256];
1.252 djm 1098: const char *host;
1.278 markus 1099: int r;
1.99 markus 1100:
1101: debug2("input_userauth_passwd_changereq");
1102:
1103: if (authctxt == NULL)
1104: fatal("input_userauth_passwd_changereq: "
1105: "no authentication context");
1.252 djm 1106: host = options.host_key_alias ? options.host_key_alias : authctxt->host;
1.99 markus 1107:
1.278 markus 1108: if ((r = sshpkt_get_cstring(ssh, &info, NULL)) != 0 ||
1109: (r = sshpkt_get_cstring(ssh, &lang, NULL)) != 0)
1110: goto out;
1.99 markus 1111: if (strlen(info) > 0)
1.116 itojun 1112: logit("%s", info);
1.278 markus 1113: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1114: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1115: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1116: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1117: (r = sshpkt_put_u8(ssh, 1)) != 0) /* additional info */
1118: goto out;
1119:
1.104 deraadt 1120: snprintf(prompt, sizeof(prompt),
1.99 markus 1121: "Enter %.30s@%.128s's old password: ",
1.175 dtucker 1122: authctxt->server_user, host);
1.99 markus 1123: password = read_passphrase(prompt, 0);
1.278 markus 1124: if ((r = sshpkt_put_cstring(ssh, password)) != 0)
1125: goto out;
1126:
1127: freezero(password, strlen(password));
1.99 markus 1128: password = NULL;
1129: while (password == NULL) {
1.104 deraadt 1130: snprintf(prompt, sizeof(prompt),
1.99 markus 1131: "Enter %.30s@%.128s's new password: ",
1.175 dtucker 1132: authctxt->server_user, host);
1.99 markus 1133: password = read_passphrase(prompt, RP_ALLOW_EOF);
1134: if (password == NULL) {
1135: /* bail out */
1.278 markus 1136: r = 0;
1137: goto out;
1.99 markus 1138: }
1.104 deraadt 1139: snprintf(prompt, sizeof(prompt),
1.99 markus 1140: "Retype %.30s@%.128s's new password: ",
1.175 dtucker 1141: authctxt->server_user, host);
1.99 markus 1142: retype = read_passphrase(prompt, 0);
1143: if (strcmp(password, retype) != 0) {
1.278 markus 1144: freezero(password, strlen(password));
1.116 itojun 1145: logit("Mismatch; try again, EOF to quit.");
1.99 markus 1146: password = NULL;
1147: }
1.278 markus 1148: freezero(retype, strlen(retype));
1.99 markus 1149: }
1.278 markus 1150: if ((r = sshpkt_put_cstring(ssh, password)) != 0 ||
1151: (r = sshpkt_add_padding(ssh, 64)) != 0 ||
1152: (r = sshpkt_send(ssh)) != 0)
1153: goto out;
1.104 deraadt 1154:
1.278 markus 1155: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
1.99 markus 1156: &input_userauth_passwd_changereq);
1.278 markus 1157: r = 0;
1158: out:
1159: if (password)
1160: freezero(password, strlen(password));
1161: free(info);
1162: free(lang);
1163: return r;
1.117 markus 1164: }
1165:
1.272 djm 1166: /*
1167: * Select an algorithm for publickey signatures.
1168: * Returns algorithm (caller must free) or NULL if no mutual algorithm found.
1169: *
1170: * Call with ssh==NULL to ignore server-sig-algs extension list and
1171: * only attempt with the key's base signature type.
1172: */
1173: static char *
1174: key_sig_algorithm(struct ssh *ssh, const struct sshkey *key)
1.231 markus 1175: {
1.274 djm 1176: char *allowed, *oallowed, *cp, *tmp, *alg = NULL;
1.348 djm 1177: const char *server_sig_algs;
1.231 markus 1178:
1.272 djm 1179: /*
1180: * The signature algorithm will only differ from the key algorithm
1181: * for RSA keys/certs and when the server advertises support for
1182: * newer (SHA2) algorithms.
1183: */
1184: if (ssh == NULL || ssh->kex->server_sig_algs == NULL ||
1.288 djm 1185: (key->type != KEY_RSA && key->type != KEY_RSA_CERT) ||
1.345 djm 1186: (key->type == KEY_RSA_CERT && (ssh->compat & SSH_BUG_SIGTYPE))) {
1.272 djm 1187: /* Filter base key signature alg against our configuration */
1.279 markus 1188: return match_list(sshkey_ssh_name(key),
1.342 dtucker 1189: options.pubkey_accepted_algos, NULL);
1.231 markus 1190: }
1191:
1.272 djm 1192: /*
1.348 djm 1193: * Workaround OpenSSH 7.4 bug: this version supports RSA/SHA-2 but
1194: * fails to advertise it via SSH2_MSG_EXT_INFO.
1195: */
1196: server_sig_algs = ssh->kex->server_sig_algs;
1197: if (key->type == KEY_RSA && (ssh->compat & SSH_BUG_SIGTYPE74))
1198: server_sig_algs = "rsa-sha2-256,rsa-sha2-512";
1199:
1200: /*
1.272 djm 1201: * For RSA keys/certs, since these might have a different sig type:
1.342 dtucker 1202: * find the first entry in PubkeyAcceptedAlgorithms of the right type
1.272 djm 1203: * that also appears in the supported signature algorithms list from
1204: * the server.
1205: */
1.342 dtucker 1206: oallowed = allowed = xstrdup(options.pubkey_accepted_algos);
1.272 djm 1207: while ((cp = strsep(&allowed, ",")) != NULL) {
1208: if (sshkey_type_from_name(cp) != key->type)
1209: continue;
1.323 djm 1210: tmp = match_list(sshkey_sigalg_by_name(cp),
1.348 djm 1211: server_sig_algs, NULL);
1.274 djm 1212: if (tmp != NULL)
1213: alg = xstrdup(cp);
1214: free(tmp);
1.272 djm 1215: if (alg != NULL)
1216: break;
1.269 djm 1217: }
1.272 djm 1218: free(oallowed);
1219: return alg;
1.269 djm 1220: }
1221:
1.117 markus 1222: static int
1.214 djm 1223: identity_sign(struct identity *id, u_char **sigp, size_t *lenp,
1.272 djm 1224: const u_char *data, size_t datalen, u_int compat, const char *alg)
1.117 markus 1225: {
1.309 djm 1226: struct sshkey *sign_key = NULL, *prv = NULL;
1.341 djm 1227: int retried = 0, r = SSH_ERR_INTERNAL_ERROR;
1.312 djm 1228: struct notifier_ctx *notifier = NULL;
1.325 djm 1229: char *fp = NULL, *pin = NULL, *prompt = NULL;
1.309 djm 1230:
1231: *sigp = NULL;
1232: *lenp = 0;
1.99 markus 1233:
1.272 djm 1234: /* The agent supports this key. */
1.269 djm 1235: if (id->key != NULL && id->agent_fd != -1) {
1.272 djm 1236: return ssh_agent_sign(id->agent_fd, id->key, sigp, lenp,
1237: data, datalen, alg, compat);
1.269 djm 1238: }
1.214 djm 1239:
1.117 markus 1240: /*
1.272 djm 1241: * We have already loaded the private key or the private key is
1242: * stored in external hardware.
1.117 markus 1243: */
1.255 djm 1244: if (id->key != NULL &&
1.272 djm 1245: (id->isprivate || (id->key->flags & SSHKEY_FLAG_EXT))) {
1.309 djm 1246: sign_key = id->key;
1247: } else {
1248: /* Load the private key from the file. */
1249: if ((prv = load_identity_file(id)) == NULL)
1250: return SSH_ERR_KEY_NOT_FOUND;
1251: if (id->key != NULL && !sshkey_equal_public(prv, id->key)) {
1.331 djm 1252: error_f("private key %s contents do not match public",
1.347 djm 1253: id->filename);
1.309 djm 1254: r = SSH_ERR_KEY_NOT_FOUND;
1255: goto out;
1256: }
1257: sign_key = prv;
1.325 djm 1258: if (sshkey_is_sk(sign_key)) {
1259: if ((sign_key->sk_flags &
1260: SSH_SK_USER_VERIFICATION_REQD)) {
1.341 djm 1261: retry_pin:
1.325 djm 1262: xasprintf(&prompt, "Enter PIN for %s key %s: ",
1263: sshkey_type(sign_key), id->filename);
1264: pin = read_passphrase(prompt, 0);
1265: }
1266: if ((sign_key->sk_flags & SSH_SK_USER_PRESENCE_REQD)) {
1267: /* XXX should batch mode just skip these? */
1268: if ((fp = sshkey_fingerprint(sign_key,
1269: options.fingerprint_hash,
1270: SSH_FP_DEFAULT)) == NULL)
1.331 djm 1271: fatal_f("fingerprint failed");
1.325 djm 1272: notifier = notify_start(options.batch_mode,
1273: "Confirm user presence for key %s %s",
1274: sshkey_type(sign_key), fp);
1275: free(fp);
1276: }
1.312 djm 1277: }
1.272 djm 1278: }
1.310 djm 1279: if ((r = sshkey_sign(sign_key, sigp, lenp, data, datalen,
1.325 djm 1280: alg, options.sk_provider, pin, compat)) != 0) {
1.331 djm 1281: debug_fr(r, "sshkey_sign");
1.341 djm 1282: if (pin == NULL && !retried && sshkey_is_sk(sign_key) &&
1283: r == SSH_ERR_KEY_WRONG_PASSPHRASE) {
1284: notify_complete(notifier, NULL);
1285: notifier = NULL;
1286: retried = 1;
1287: goto retry_pin;
1288: }
1.309 djm 1289: goto out;
1290: }
1.341 djm 1291:
1.309 djm 1292: /*
1293: * PKCS#11 tokens may not support all signature algorithms,
1294: * so check what we get back.
1295: */
1296: if ((r = sshkey_check_sigtype(*sigp, *lenp, alg)) != 0) {
1.331 djm 1297: debug_fr(r, "sshkey_check_sigtype");
1.309 djm 1298: goto out;
1.265 djm 1299: }
1.309 djm 1300: /* success */
1301: r = 0;
1302: out:
1.325 djm 1303: free(prompt);
1304: if (pin != NULL)
1305: freezero(pin, strlen(pin));
1.341 djm 1306: notify_complete(notifier, r == 0 ? "User presence confirmed" : NULL);
1.214 djm 1307: sshkey_free(prv);
1.269 djm 1308: return r;
1.51 markus 1309: }
1310:
1.76 itojun 1311: static int
1.255 djm 1312: id_filename_matches(Identity *id, Identity *private_id)
1313: {
1314: const char *suffixes[] = { ".pub", "-cert.pub", NULL };
1315: size_t len = strlen(id->filename), plen = strlen(private_id->filename);
1316: size_t i, slen;
1317:
1318: if (strcmp(id->filename, private_id->filename) == 0)
1319: return 1;
1320: for (i = 0; suffixes[i]; i++) {
1321: slen = strlen(suffixes[i]);
1322: if (len > slen && plen == len - slen &&
1323: strcmp(id->filename + (len - slen), suffixes[i]) == 0 &&
1324: memcmp(id->filename, private_id->filename, plen) == 0)
1325: return 1;
1326: }
1327: return 0;
1328: }
1329:
1330: static int
1.295 djm 1331: sign_and_send_pubkey(struct ssh *ssh, Identity *id)
1.1 markus 1332: {
1.295 djm 1333: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.272 djm 1334: struct sshbuf *b = NULL;
1335: Identity *private_id, *sign_id = NULL;
1336: u_char *signature = NULL;
1337: size_t slen = 0, skip = 0;
1338: int r, fallback_sigtype, sent = 0;
1339: char *alg = NULL, *fp = NULL;
1340: const char *loc = "";
1.1 markus 1341:
1.222 djm 1342: if ((fp = sshkey_fingerprint(id->key, options.fingerprint_hash,
1343: SSH_FP_DEFAULT)) == NULL)
1344: return 0;
1.51 markus 1345:
1.331 djm 1346: debug3_f("%s %s", sshkey_type(id->key), fp);
1.1 markus 1347:
1.227 djm 1348: /*
1349: * If the key is an certificate, try to find a matching private key
1350: * and use it to complete the signature.
1.241 djm 1351: * If no such private key exists, fall back to trying the certificate
1352: * key itself in case it has a private half already loaded.
1.272 djm 1353: * This will try to set sign_id to the private key that will perform
1354: * the signature.
1.227 djm 1355: */
1.272 djm 1356: if (sshkey_is_cert(id->key)) {
1.227 djm 1357: TAILQ_FOREACH(private_id, &authctxt->keys, next) {
1358: if (sshkey_equal_public(id->key, private_id->key) &&
1359: id->key->type != private_id->key->type) {
1.272 djm 1360: sign_id = private_id;
1.227 djm 1361: break;
1362: }
1363: }
1.255 djm 1364: /*
1365: * Exact key matches are preferred, but also allow
1366: * filename matches for non-PKCS#11/agent keys that
1367: * didn't load public keys. This supports the case
1368: * of keeping just a private key file and public
1369: * certificate on disk.
1370: */
1.272 djm 1371: if (sign_id == NULL &&
1372: !id->isprivate && id->agent_fd == -1 &&
1.255 djm 1373: (id->key->flags & SSHKEY_FLAG_EXT) == 0) {
1374: TAILQ_FOREACH(private_id, &authctxt->keys, next) {
1375: if (private_id->key == NULL &&
1376: id_filename_matches(id, private_id)) {
1.272 djm 1377: sign_id = private_id;
1.255 djm 1378: break;
1379: }
1380: }
1381: }
1.272 djm 1382: if (sign_id != NULL) {
1.331 djm 1383: debug2_f("using private key \"%s\"%s for "
1.349 djm 1384: "certificate", sign_id->filename,
1385: sign_id->agent_fd != -1 ? " from agent" : "");
1.227 djm 1386: } else {
1.331 djm 1387: debug_f("no separate private key for certificate "
1388: "\"%s\"", id->filename);
1.227 djm 1389: }
1390: }
1391:
1.272 djm 1392: /*
1393: * If the above didn't select another identity to do the signing
1394: * then default to the one we started with.
1395: */
1396: if (sign_id == NULL)
1397: sign_id = id;
1398:
1399: /* assemble and sign data */
1400: for (fallback_sigtype = 0; fallback_sigtype <= 1; fallback_sigtype++) {
1401: free(alg);
1402: slen = 0;
1403: signature = NULL;
1404: if ((alg = key_sig_algorithm(fallback_sigtype ? NULL : ssh,
1405: id->key)) == NULL) {
1.331 djm 1406: error_f("no mutual signature supported");
1.272 djm 1407: goto out;
1408: }
1.331 djm 1409: debug3_f("signing using %s %s", alg, fp);
1.272 djm 1410:
1411: sshbuf_free(b);
1412: if ((b = sshbuf_new()) == NULL)
1.331 djm 1413: fatal_f("sshbuf_new failed");
1.345 djm 1414: if (ssh->compat & SSH_OLD_SESSIONID) {
1.346 djm 1415: if ((r = sshbuf_putb(b, ssh->kex->session_id)) != 0)
1416: fatal_fr(r, "sshbuf_putb");
1.272 djm 1417: } else {
1.346 djm 1418: if ((r = sshbuf_put_stringb(b,
1419: ssh->kex->session_id)) != 0)
1420: fatal_fr(r, "sshbuf_put_stringb");
1.272 djm 1421: }
1.278 markus 1422: skip = sshbuf_len(b);
1.272 djm 1423: if ((r = sshbuf_put_u8(b, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1424: (r = sshbuf_put_cstring(b, authctxt->server_user)) != 0 ||
1425: (r = sshbuf_put_cstring(b, authctxt->service)) != 0 ||
1426: (r = sshbuf_put_cstring(b, authctxt->method->name)) != 0 ||
1427: (r = sshbuf_put_u8(b, 1)) != 0 ||
1428: (r = sshbuf_put_cstring(b, alg)) != 0 ||
1429: (r = sshkey_puts(id->key, b)) != 0) {
1.331 djm 1430: fatal_fr(r, "assemble signed data");
1.272 djm 1431: }
1432:
1433: /* generate signature */
1434: r = identity_sign(sign_id, &signature, &slen,
1.345 djm 1435: sshbuf_ptr(b), sshbuf_len(b), ssh->compat, alg);
1.272 djm 1436: if (r == 0)
1437: break;
1438: else if (r == SSH_ERR_KEY_NOT_FOUND)
1439: goto out; /* soft failure */
1440: else if (r == SSH_ERR_SIGN_ALG_UNSUPPORTED &&
1441: !fallback_sigtype) {
1442: if (sign_id->agent_fd != -1)
1443: loc = "agent ";
1444: else if ((sign_id->key->flags & SSHKEY_FLAG_EXT) != 0)
1445: loc = "token ";
1446: logit("%skey %s %s returned incorrect signature type",
1447: loc, sshkey_type(id->key), fp);
1448: continue;
1449: }
1.331 djm 1450: error_fr(r, "signing failed for %s \"%s\"%s",
1.315 djm 1451: sshkey_type(sign_id->key), sign_id->filename,
1.331 djm 1452: id->agent_fd != -1 ? " from agent" : "");
1.272 djm 1453: goto out;
1.17 markus 1454: }
1.272 djm 1455: if (slen == 0 || signature == NULL) /* shouldn't happen */
1.331 djm 1456: fatal_f("no signature");
1.51 markus 1457:
1.1 markus 1458: /* append signature */
1.272 djm 1459: if ((r = sshbuf_put_string(b, signature, slen)) != 0)
1.331 djm 1460: fatal_fr(r, "append signature");
1.1 markus 1461:
1.272 djm 1462: #ifdef DEBUG_PK
1463: sshbuf_dump(b, stderr);
1464: #endif
1.1 markus 1465: /* skip session id and packet type */
1.272 djm 1466: if ((r = sshbuf_consume(b, skip + 1)) != 0)
1.331 djm 1467: fatal_fr(r, "consume");
1.1 markus 1468:
1469: /* put remaining data from buffer into packet */
1.272 djm 1470: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1471: (r = sshpkt_putb(ssh, b)) != 0 ||
1472: (r = sshpkt_send(ssh)) != 0)
1.331 djm 1473: fatal_fr(r, "enqueue request");
1.272 djm 1474:
1475: /* success */
1476: sent = 1;
1.17 markus 1477:
1.272 djm 1478: out:
1479: free(fp);
1480: free(alg);
1481: sshbuf_free(b);
1482: freezero(signature, slen);
1483: return sent;
1.16 markus 1484: }
1485:
1.76 itojun 1486: static int
1.295 djm 1487: send_pubkey_test(struct ssh *ssh, Identity *id)
1.20 markus 1488: {
1.295 djm 1489: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.272 djm 1490: u_char *blob = NULL;
1491: char *alg = NULL;
1.278 markus 1492: size_t bloblen;
1493: u_int have_sig = 0;
1494: int sent = 0, r;
1.20 markus 1495:
1.272 djm 1496: if ((alg = key_sig_algorithm(ssh, id->key)) == NULL) {
1.331 djm 1497: debug_f("no mutual signature algorithm");
1.272 djm 1498: goto out;
1499: }
1.16 markus 1500:
1.278 markus 1501: if ((r = sshkey_to_blob(id->key, &blob, &bloblen)) != 0) {
1.51 markus 1502: /* we cannot handle this key */
1.331 djm 1503: debug3_f("cannot handle key");
1.272 djm 1504: goto out;
1.16 markus 1505: }
1.51 markus 1506: /* register callback for USERAUTH_PK_OK message */
1.278 markus 1507: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_PK_OK, &input_userauth_pk_ok);
1.51 markus 1508:
1.278 markus 1509: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1510: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1511: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1512: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1513: (r = sshpkt_put_u8(ssh, have_sig)) != 0 ||
1514: (r = sshpkt_put_cstring(ssh, alg)) != 0 ||
1515: (r = sshpkt_put_string(ssh, blob, bloblen)) != 0 ||
1516: (r = sshpkt_send(ssh)) != 0)
1.331 djm 1517: fatal_fr(r, "send packet");
1.272 djm 1518: sent = 1;
1.278 markus 1519:
1520: out:
1.272 djm 1521: free(alg);
1.197 djm 1522: free(blob);
1.272 djm 1523: return sent;
1.51 markus 1524: }
1525:
1.259 markus 1526: static struct sshkey *
1.229 jcs 1527: load_identity_file(Identity *id)
1.51 markus 1528: {
1.259 markus 1529: struct sshkey *private = NULL;
1.229 jcs 1530: char prompt[300], *passphrase, *comment;
1.308 dtucker 1531: int r, quit = 0, i;
1.52 markus 1532: struct stat st;
1.16 markus 1533:
1.306 deraadt 1534: if (stat(id->filename, &st) == -1) {
1.330 djm 1535: do_log2(id->userprovided ?
1536: SYSLOG_LEVEL_INFO : SYSLOG_LEVEL_DEBUG3,
1537: "no such identity: %s: %s", id->filename, strerror(errno));
1.52 markus 1538: return NULL;
1539: }
1.214 djm 1540: snprintf(prompt, sizeof prompt,
1.229 jcs 1541: "Enter passphrase for key '%.100s': ", id->filename);
1.214 djm 1542: for (i = 0; i <= options.number_of_password_prompts; i++) {
1543: if (i == 0)
1544: passphrase = "";
1545: else {
1.20 markus 1546: passphrase = read_passphrase(prompt, 0);
1.214 djm 1547: if (*passphrase == '\0') {
1.20 markus 1548: debug2("no passphrase given, try next key");
1.214 djm 1549: free(passphrase);
1550: break;
1551: }
1552: }
1.229 jcs 1553: switch ((r = sshkey_load_private_type(KEY_UNSPEC, id->filename,
1.308 dtucker 1554: passphrase, &private, &comment))) {
1.214 djm 1555: case 0:
1556: break;
1557: case SSH_ERR_KEY_WRONG_PASSPHRASE:
1558: if (options.batch_mode) {
1559: quit = 1;
1560: break;
1561: }
1.215 djm 1562: if (i != 0)
1563: debug2("bad passphrase given, try again...");
1.214 djm 1564: break;
1565: case SSH_ERR_SYSTEM_ERROR:
1566: if (errno == ENOENT) {
1.331 djm 1567: debug2_r(r, "Load key \"%s\"", id->filename);
1.51 markus 1568: quit = 1;
1.214 djm 1569: break;
1.20 markus 1570: }
1.214 djm 1571: /* FALLTHROUGH */
1572: default:
1.331 djm 1573: error_r(r, "Load key \"%s\"", id->filename);
1.214 djm 1574: quit = 1;
1575: break;
1576: }
1.311 markus 1577: if (private != NULL && sshkey_is_sk(private) &&
1.309 djm 1578: options.sk_provider == NULL) {
1.319 naddy 1579: debug("key \"%s\" is an authenticator-hosted key, "
1580: "but no provider specified", id->filename);
1.309 djm 1581: sshkey_free(private);
1582: private = NULL;
1583: quit = 1;
1584: }
1.230 djm 1585: if (!quit && private != NULL && id->agent_fd == -1 &&
1.229 jcs 1586: !(id->key && id->isprivate))
1587: maybe_add_key_to_agent(id->filename, private, comment,
1588: passphrase);
1.278 markus 1589: if (i > 0)
1590: freezero(passphrase, strlen(passphrase));
1.232 mmcc 1591: free(comment);
1.214 djm 1592: if (private != NULL || quit)
1593: break;
1.16 markus 1594: }
1.51 markus 1595: return private;
1596: }
1597:
1.272 djm 1598: static int
1599: key_type_allowed_by_config(struct sshkey *key)
1600: {
1601: if (match_pattern_list(sshkey_ssh_name(key),
1.342 dtucker 1602: options.pubkey_accepted_algos, 0) == 1)
1.272 djm 1603: return 1;
1604:
1605: /* RSA keys/certs might be allowed by alternate signature types */
1606: switch (key->type) {
1607: case KEY_RSA:
1608: if (match_pattern_list("rsa-sha2-512",
1.342 dtucker 1609: options.pubkey_accepted_algos, 0) == 1)
1.272 djm 1610: return 1;
1611: if (match_pattern_list("rsa-sha2-256",
1.342 dtucker 1612: options.pubkey_accepted_algos, 0) == 1)
1.272 djm 1613: return 1;
1614: break;
1615: case KEY_RSA_CERT:
1616: if (match_pattern_list("rsa-sha2-512-cert-v01@openssh.com",
1.342 dtucker 1617: options.pubkey_accepted_algos, 0) == 1)
1.272 djm 1618: return 1;
1619: if (match_pattern_list("rsa-sha2-256-cert-v01@openssh.com",
1.342 dtucker 1620: options.pubkey_accepted_algos, 0) == 1)
1.272 djm 1621: return 1;
1622: break;
1623: }
1624: return 0;
1625: }
1626:
1627:
1.117 markus 1628: /*
1629: * try keys in the following order:
1.332 djm 1630: * 1. certificates listed in the config file
1631: * 2. other input certificates
1.227 djm 1632: * 3. agent keys that are found in the config file
1633: * 4. other agent keys
1634: * 5. keys that are only listed in the config file
1.117 markus 1635: */
1636: static void
1637: pubkey_prepare(Authctxt *authctxt)
1.51 markus 1638: {
1.214 djm 1639: struct identity *id, *id2, *tmp;
1640: struct idlist agent, files, *preferred;
1641: struct sshkey *key;
1.230 djm 1642: int agent_fd = -1, i, r, found;
1.214 djm 1643: size_t j;
1644: struct ssh_identitylist *idlist;
1.287 djm 1645: char *ident;
1.51 markus 1646:
1.117 markus 1647: TAILQ_INIT(&agent); /* keys from the agent */
1648: TAILQ_INIT(&files); /* keys from the config file */
1649: preferred = &authctxt->keys;
1650: TAILQ_INIT(preferred); /* preferred order of keys */
1651:
1.190 djm 1652: /* list of keys stored in the filesystem and PKCS#11 */
1.117 markus 1653: for (i = 0; i < options.num_identity_files; i++) {
1654: key = options.identity_keys[i];
1.309 djm 1655: if (key && key->cert &&
1656: key->cert->type != SSH2_CERT_TYPE_USER) {
1.331 djm 1657: debug_f("ignoring certificate %s: not a user "
1658: "certificate", options.identity_files[i]);
1.309 djm 1659: continue;
1660: }
1.311 markus 1661: if (key && sshkey_is_sk(key) && options.sk_provider == NULL) {
1.331 djm 1662: debug_f("ignoring authenticator-hosted key %s as no "
1.309 djm 1663: "SecurityKeyProvider has been specified",
1.331 djm 1664: options.identity_files[i]);
1.117 markus 1665: continue;
1.309 djm 1666: }
1.117 markus 1667: options.identity_keys[i] = NULL;
1.150 djm 1668: id = xcalloc(1, sizeof(*id));
1.230 djm 1669: id->agent_fd = -1;
1.117 markus 1670: id->key = key;
1671: id->filename = xstrdup(options.identity_files[i]);
1.192 dtucker 1672: id->userprovided = options.identity_file_userprovided[i];
1.117 markus 1673: TAILQ_INSERT_TAIL(&files, id, next);
1.190 djm 1674: }
1.227 djm 1675: /* list of certificates specified by user */
1676: for (i = 0; i < options.num_certificate_files; i++) {
1677: key = options.certificates[i];
1.278 markus 1678: if (!sshkey_is_cert(key) || key->cert == NULL ||
1.309 djm 1679: key->cert->type != SSH2_CERT_TYPE_USER) {
1.331 djm 1680: debug_f("ignoring certificate %s: not a user "
1681: "certificate", options.identity_files[i]);
1.227 djm 1682: continue;
1.309 djm 1683: }
1.311 markus 1684: if (key && sshkey_is_sk(key) && options.sk_provider == NULL) {
1.331 djm 1685: debug_f("ignoring authenticator-hosted key "
1.319 naddy 1686: "certificate %s as no "
1.309 djm 1687: "SecurityKeyProvider has been specified",
1.331 djm 1688: options.identity_files[i]);
1.309 djm 1689: continue;
1690: }
1.227 djm 1691: id = xcalloc(1, sizeof(*id));
1.230 djm 1692: id->agent_fd = -1;
1.227 djm 1693: id->key = key;
1694: id->filename = xstrdup(options.certificate_files[i]);
1695: id->userprovided = options.certificate_file_userprovided[i];
1696: TAILQ_INSERT_TAIL(preferred, id, next);
1.117 markus 1697: }
1698: /* list of keys supported by the agent */
1.214 djm 1699: if ((r = ssh_get_authentication_socket(&agent_fd)) != 0) {
1700: if (r != SSH_ERR_AGENT_NOT_PRESENT)
1.331 djm 1701: debug_fr(r, "ssh_get_authentication_socket");
1.258 naddy 1702: } else if ((r = ssh_fetch_identitylist(agent_fd, &idlist)) != 0) {
1.214 djm 1703: if (r != SSH_ERR_AGENT_NO_IDENTITIES)
1.331 djm 1704: debug_fr(r, "ssh_fetch_identitylist");
1.237 markus 1705: close(agent_fd);
1.214 djm 1706: } else {
1707: for (j = 0; j < idlist->nkeys; j++) {
1.117 markus 1708: found = 0;
1709: TAILQ_FOREACH(id, &files, next) {
1.214 djm 1710: /*
1711: * agent keys from the config file are
1712: * preferred
1713: */
1714: if (sshkey_equal(idlist->keys[j], id->key)) {
1.117 markus 1715: TAILQ_REMOVE(&files, id, next);
1716: TAILQ_INSERT_TAIL(preferred, id, next);
1.214 djm 1717: id->agent_fd = agent_fd;
1.117 markus 1718: found = 1;
1719: break;
1720: }
1721: }
1.135 markus 1722: if (!found && !options.identities_only) {
1.150 djm 1723: id = xcalloc(1, sizeof(*id));
1.214 djm 1724: /* XXX "steals" key/comment from idlist */
1725: id->key = idlist->keys[j];
1726: id->filename = idlist->comments[j];
1727: idlist->keys[j] = NULL;
1728: idlist->comments[j] = NULL;
1729: id->agent_fd = agent_fd;
1.117 markus 1730: TAILQ_INSERT_TAIL(&agent, id, next);
1731: }
1732: }
1.214 djm 1733: ssh_free_identitylist(idlist);
1.117 markus 1734: /* append remaining agent keys */
1.324 bket 1735: TAILQ_CONCAT(preferred, &agent, next);
1.214 djm 1736: authctxt->agent_fd = agent_fd;
1.244 djm 1737: }
1738: /* Prefer PKCS11 keys that are explicitly listed */
1739: TAILQ_FOREACH_SAFE(id, &files, next, tmp) {
1740: if (id->key == NULL || (id->key->flags & SSHKEY_FLAG_EXT) == 0)
1741: continue;
1742: found = 0;
1743: TAILQ_FOREACH(id2, &files, next) {
1744: if (id2->key == NULL ||
1.321 djm 1745: (id2->key->flags & SSHKEY_FLAG_EXT) != 0)
1.244 djm 1746: continue;
1747: if (sshkey_equal(id->key, id2->key)) {
1748: TAILQ_REMOVE(&files, id, next);
1749: TAILQ_INSERT_TAIL(preferred, id, next);
1750: found = 1;
1751: break;
1752: }
1753: }
1754: /* If IdentitiesOnly set and key not found then don't use it */
1755: if (!found && options.identities_only) {
1756: TAILQ_REMOVE(&files, id, next);
1.278 markus 1757: freezero(id, sizeof(*id));
1.244 djm 1758: }
1.117 markus 1759: }
1760: /* append remaining keys from the config file */
1.324 bket 1761: TAILQ_CONCAT(preferred, &files, next);
1.342 dtucker 1762: /* finally, filter by PubkeyAcceptedAlgorithms */
1.228 djm 1763: TAILQ_FOREACH_SAFE(id, preferred, next, id2) {
1.273 djm 1764: if (id->key != NULL && !key_type_allowed_by_config(id->key)) {
1.228 djm 1765: debug("Skipping %s key %s - "
1.342 dtucker 1766: "corresponding algo not in PubkeyAcceptedAlgorithms",
1.228 djm 1767: sshkey_ssh_name(id->key), id->filename);
1768: TAILQ_REMOVE(preferred, id, next);
1769: sshkey_free(id->key);
1770: free(id->filename);
1771: memset(id, 0, sizeof(*id));
1772: continue;
1773: }
1.117 markus 1774: }
1.287 djm 1775: /* List the keys we plan on using */
1776: TAILQ_FOREACH_SAFE(id, preferred, next, id2) {
1777: ident = format_identity(id);
1778: debug("Will attempt key: %s", ident);
1779: free(ident);
1780: }
1.331 djm 1781: debug2_f("done");
1.17 markus 1782: }
1783:
1.117 markus 1784: static void
1.303 djm 1785: pubkey_cleanup(struct ssh *ssh)
1.51 markus 1786: {
1.302 djm 1787: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.117 markus 1788: Identity *id;
1.51 markus 1789:
1.289 djm 1790: if (authctxt->agent_fd != -1) {
1.214 djm 1791: ssh_close_authentication_socket(authctxt->agent_fd);
1.289 djm 1792: authctxt->agent_fd = -1;
1793: }
1.117 markus 1794: for (id = TAILQ_FIRST(&authctxt->keys); id;
1795: id = TAILQ_FIRST(&authctxt->keys)) {
1796: TAILQ_REMOVE(&authctxt->keys, id, next);
1.235 mmcc 1797: sshkey_free(id->key);
1.197 djm 1798: free(id->filename);
1799: free(id);
1.117 markus 1800: }
1.1 markus 1801: }
1802:
1.251 djm 1803: static void
1804: pubkey_reset(Authctxt *authctxt)
1805: {
1806: Identity *id;
1807:
1808: TAILQ_FOREACH(id, &authctxt->keys, next)
1809: id->tried = 0;
1810: }
1811:
1.225 markus 1812: static int
1.345 djm 1813: try_identity(struct ssh *ssh, Identity *id)
1.225 markus 1814: {
1815: if (!id->key)
1816: return (0);
1.279 markus 1817: if (sshkey_type_plain(id->key->type) == KEY_RSA &&
1.345 djm 1818: (ssh->compat & SSH_BUG_RSASIGMD5) != 0) {
1.225 markus 1819: debug("Skipped %s key %s for RSA/MD5 server",
1.279 markus 1820: sshkey_type(id->key), id->filename);
1.225 markus 1821: return (0);
1822: }
1.257 djm 1823: return 1;
1.225 markus 1824: }
1825:
1.302 djm 1826: static int
1.295 djm 1827: userauth_pubkey(struct ssh *ssh)
1.20 markus 1828: {
1.295 djm 1829: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.117 markus 1830: Identity *id;
1.20 markus 1831: int sent = 0;
1.287 djm 1832: char *ident;
1.20 markus 1833:
1.117 markus 1834: while ((id = TAILQ_FIRST(&authctxt->keys))) {
1835: if (id->tried++)
1836: return (0);
1.127 markus 1837: /* move key to the end of the queue */
1.117 markus 1838: TAILQ_REMOVE(&authctxt->keys, id, next);
1839: TAILQ_INSERT_TAIL(&authctxt->keys, id, next);
1840: /*
1841: * send a test message if we have the public key. for
1842: * encrypted keys we cannot do this and have to load the
1843: * private key instead
1844: */
1.200 djm 1845: if (id->key != NULL) {
1.345 djm 1846: if (try_identity(ssh, id)) {
1.287 djm 1847: ident = format_identity(id);
1848: debug("Offering public key: %s", ident);
1849: free(ident);
1.295 djm 1850: sent = send_pubkey_test(ssh, id);
1.200 djm 1851: }
1852: } else {
1.117 markus 1853: debug("Trying private key: %s", id->filename);
1.229 jcs 1854: id->key = load_identity_file(id);
1.117 markus 1855: if (id->key != NULL) {
1.345 djm 1856: if (try_identity(ssh, id)) {
1.225 markus 1857: id->isprivate = 1;
1.295 djm 1858: sent = sign_and_send_pubkey(ssh, id);
1.200 djm 1859: }
1.278 markus 1860: sshkey_free(id->key);
1.117 markus 1861: id->key = NULL;
1.251 djm 1862: id->isprivate = 0;
1.51 markus 1863: }
1864: }
1.117 markus 1865: if (sent)
1866: return (sent);
1.28 markus 1867: }
1.117 markus 1868: return (0);
1.20 markus 1869: }
1870:
1.23 markus 1871: /*
1872: * Send userauth request message specifying keyboard-interactive method.
1873: */
1.302 djm 1874: static int
1.295 djm 1875: userauth_kbdint(struct ssh *ssh)
1.23 markus 1876: {
1.295 djm 1877: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.278 markus 1878: int r;
1.23 markus 1879:
1.292 djm 1880: if (authctxt->attempt_kbdint++ >= options.number_of_password_prompts)
1.23 markus 1881: return 0;
1.82 markus 1882: /* disable if no SSH2_MSG_USERAUTH_INFO_REQUEST has been seen */
1.292 djm 1883: if (authctxt->attempt_kbdint > 1 && !authctxt->info_req_seen) {
1.82 markus 1884: debug3("userauth_kbdint: disable: no info_req_seen");
1.278 markus 1885: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_INFO_REQUEST, NULL);
1.82 markus 1886: return 0;
1887: }
1.23 markus 1888:
1889: debug2("userauth_kbdint");
1.278 markus 1890: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1891: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1892: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1893: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1894: (r = sshpkt_put_cstring(ssh, "")) != 0 || /* lang */
1895: (r = sshpkt_put_cstring(ssh, options.kbd_interactive_devices ?
1896: options.kbd_interactive_devices : "")) != 0 ||
1897: (r = sshpkt_send(ssh)) != 0)
1.331 djm 1898: fatal_fr(r, "send packet");
1.23 markus 1899:
1.278 markus 1900: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_INFO_REQUEST, &input_userauth_info_req);
1.23 markus 1901: return 1;
1902: }
1903:
1904: /*
1.46 markus 1905: * parse INFO_REQUEST, prompt user and send INFO_RESPONSE
1.23 markus 1906: */
1.302 djm 1907: static int
1.261 markus 1908: input_userauth_info_req(int type, u_int32_t seq, struct ssh *ssh)
1.23 markus 1909: {
1.260 markus 1910: Authctxt *authctxt = ssh->authctxt;
1.278 markus 1911: char *name = NULL, *inst = NULL, *lang = NULL, *prompt = NULL;
1.335 djm 1912: char *display_prompt = NULL, *response = NULL;
1.278 markus 1913: u_char echo = 0;
1.32 markus 1914: u_int num_prompts, i;
1.278 markus 1915: int r;
1.23 markus 1916:
1.335 djm 1917: debug2_f("entering");
1.23 markus 1918:
1919: if (authctxt == NULL)
1.335 djm 1920: fatal_f("no authentication context");
1.82 markus 1921:
1922: authctxt->info_req_seen = 1;
1.23 markus 1923:
1.278 markus 1924: if ((r = sshpkt_get_cstring(ssh, &name, NULL)) != 0 ||
1925: (r = sshpkt_get_cstring(ssh, &inst, NULL)) != 0 ||
1926: (r = sshpkt_get_cstring(ssh, &lang, NULL)) != 0)
1927: goto out;
1.23 markus 1928: if (strlen(name) > 0)
1.116 itojun 1929: logit("%s", name);
1.23 markus 1930: if (strlen(inst) > 0)
1.116 itojun 1931: logit("%s", inst);
1.23 markus 1932:
1.278 markus 1933: if ((r = sshpkt_get_u32(ssh, &num_prompts)) != 0)
1934: goto out;
1.23 markus 1935: /*
1936: * Begin to build info response packet based on prompts requested.
1937: * We commit to providing the correct number of responses, so if
1938: * further on we run into a problem that prevents this, we have to
1939: * be sure and clean this up and send a correct error response.
1940: */
1.278 markus 1941: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_INFO_RESPONSE)) != 0 ||
1942: (r = sshpkt_put_u32(ssh, num_prompts)) != 0)
1943: goto out;
1.23 markus 1944:
1.335 djm 1945: debug2_f("num_prompts %d", num_prompts);
1.23 markus 1946: for (i = 0; i < num_prompts; i++) {
1.278 markus 1947: if ((r = sshpkt_get_cstring(ssh, &prompt, NULL)) != 0 ||
1948: (r = sshpkt_get_u8(ssh, &echo)) != 0)
1949: goto out;
1.336 djm 1950: if (asmprintf(&display_prompt, INT_MAX, NULL, "(%s@%s) %s",
1.335 djm 1951: authctxt->server_user, options.host_key_alias ?
1.336 djm 1952: options.host_key_alias : authctxt->host, prompt) == -1)
1953: fatal_f("asmprintf failed");
1.335 djm 1954: response = read_passphrase(display_prompt, echo ? RP_ECHO : 0);
1.278 markus 1955: if ((r = sshpkt_put_cstring(ssh, response)) != 0)
1956: goto out;
1957: freezero(response, strlen(response));
1.197 djm 1958: free(prompt);
1.335 djm 1959: free(display_prompt);
1960: display_prompt = response = prompt = NULL;
1.23 markus 1961: }
1.278 markus 1962: /* done with parsing incoming message. */
1963: if ((r = sshpkt_get_end(ssh)) != 0 ||
1964: (r = sshpkt_add_padding(ssh, 64)) != 0)
1965: goto out;
1966: r = sshpkt_send(ssh);
1967: out:
1968: if (response)
1969: freezero(response, strlen(response));
1970: free(prompt);
1.335 djm 1971: free(display_prompt);
1.278 markus 1972: free(name);
1973: free(inst);
1974: free(lang);
1975: return r;
1.68 markus 1976: }
1977:
1.100 markus 1978: static int
1.294 djm 1979: ssh_keysign(struct ssh *ssh, struct sshkey *key, u_char **sigp, size_t *lenp,
1.223 djm 1980: const u_char *data, size_t datalen)
1.100 markus 1981: {
1.223 djm 1982: struct sshbuf *b;
1.101 markus 1983: struct stat st;
1.100 markus 1984: pid_t pid;
1.304 deraadt 1985: int r, to[2], from[2], status;
1.295 djm 1986: int sock = ssh_packet_get_connection_in(ssh);
1.223 djm 1987: u_char rversion = 0, version = 2;
1988: void (*osigchld)(int);
1.100 markus 1989:
1.223 djm 1990: *sigp = NULL;
1991: *lenp = 0;
1.100 markus 1992:
1.306 deraadt 1993: if (stat(_PATH_SSH_KEY_SIGN, &st) == -1) {
1.331 djm 1994: error_f("not installed: %s", strerror(errno));
1.223 djm 1995: return -1;
1996: }
1997: if (fflush(stdout) != 0) {
1.331 djm 1998: error_f("fflush: %s", strerror(errno));
1.101 markus 1999: return -1;
2000: }
1.306 deraadt 2001: if (pipe(to) == -1) {
1.331 djm 2002: error_f("pipe: %s", strerror(errno));
1.100 markus 2003: return -1;
2004: }
1.306 deraadt 2005: if (pipe(from) == -1) {
1.331 djm 2006: error_f("pipe: %s", strerror(errno));
1.100 markus 2007: return -1;
2008: }
1.306 deraadt 2009: if ((pid = fork()) == -1) {
1.331 djm 2010: error_f("fork: %s", strerror(errno));
1.100 markus 2011: return -1;
2012: }
1.317 dtucker 2013: osigchld = ssh_signal(SIGCHLD, SIG_DFL);
1.100 markus 2014: if (pid == 0) {
2015: close(from[0]);
1.306 deraadt 2016: if (dup2(from[1], STDOUT_FILENO) == -1)
1.331 djm 2017: fatal_f("dup2: %s", strerror(errno));
1.100 markus 2018: close(to[1]);
1.306 deraadt 2019: if (dup2(to[0], STDIN_FILENO) == -1)
1.331 djm 2020: fatal_f("dup2: %s", strerror(errno));
1.103 markus 2021: close(from[1]);
2022: close(to[0]);
1.304 deraadt 2023:
1.306 deraadt 2024: if (dup2(sock, STDERR_FILENO + 1) == -1)
1.331 djm 2025: fatal_f("dup2: %s", strerror(errno));
1.304 deraadt 2026: sock = STDERR_FILENO + 1;
2027: fcntl(sock, F_SETFD, 0); /* keep the socket on exec */
1.223 djm 2028: closefrom(sock + 1);
1.304 deraadt 2029:
1.331 djm 2030: debug3_f("[child] pid=%ld, exec %s",
2031: (long)getpid(), _PATH_SSH_KEY_SIGN);
1.233 mmcc 2032: execl(_PATH_SSH_KEY_SIGN, _PATH_SSH_KEY_SIGN, (char *)NULL);
1.331 djm 2033: fatal_f("exec(%s): %s", _PATH_SSH_KEY_SIGN,
1.100 markus 2034: strerror(errno));
2035: }
2036: close(from[1]);
2037: close(to[0]);
1.305 djm 2038: sock = STDERR_FILENO + 1;
1.100 markus 2039:
1.223 djm 2040: if ((b = sshbuf_new()) == NULL)
1.331 djm 2041: fatal_f("sshbuf_new failed");
1.223 djm 2042: /* send # of sock, data to be signed */
1.253 djm 2043: if ((r = sshbuf_put_u32(b, sock)) != 0 ||
1.223 djm 2044: (r = sshbuf_put_string(b, data, datalen)) != 0)
1.331 djm 2045: fatal_fr(r, "buffer error");
1.223 djm 2046: if (ssh_msg_send(to[1], version, b) == -1)
1.331 djm 2047: fatal_f("couldn't send request");
1.223 djm 2048: sshbuf_reset(b);
2049: r = ssh_msg_recv(from[0], b);
1.101 markus 2050: close(from[0]);
2051: close(to[1]);
1.223 djm 2052: if (r < 0) {
1.331 djm 2053: error_f("no reply");
1.223 djm 2054: goto fail;
2055: }
1.101 markus 2056:
1.223 djm 2057: errno = 0;
1.306 deraadt 2058: while (waitpid(pid, &status, 0) == -1) {
1.223 djm 2059: if (errno != EINTR) {
1.331 djm 2060: error_f("waitpid %ld: %s", (long)pid, strerror(errno));
1.223 djm 2061: goto fail;
2062: }
2063: }
2064: if (!WIFEXITED(status)) {
1.331 djm 2065: error_f("exited abnormally");
1.223 djm 2066: goto fail;
2067: }
2068: if (WEXITSTATUS(status) != 0) {
1.331 djm 2069: error_f("exited with status %d", WEXITSTATUS(status));
1.223 djm 2070: goto fail;
2071: }
2072: if ((r = sshbuf_get_u8(b, &rversion)) != 0) {
1.331 djm 2073: error_fr(r, "buffer error");
1.223 djm 2074: goto fail;
2075: }
2076: if (rversion != version) {
1.331 djm 2077: error_f("bad version");
1.223 djm 2078: goto fail;
2079: }
2080: if ((r = sshbuf_get_string(b, sigp, lenp)) != 0) {
1.331 djm 2081: error_fr(r, "buffer error");
1.223 djm 2082: fail:
1.317 dtucker 2083: ssh_signal(SIGCHLD, osigchld);
1.223 djm 2084: sshbuf_free(b);
1.100 markus 2085: return -1;
2086: }
1.317 dtucker 2087: ssh_signal(SIGCHLD, osigchld);
1.223 djm 2088: sshbuf_free(b);
1.100 markus 2089:
2090: return 0;
2091: }
2092:
1.302 djm 2093: static int
1.295 djm 2094: userauth_hostbased(struct ssh *ssh)
1.68 markus 2095: {
1.295 djm 2096: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.223 djm 2097: struct sshkey *private = NULL;
2098: struct sshbuf *b = NULL;
2099: u_char *sig = NULL, *keyblob = NULL;
2100: char *fp = NULL, *chost = NULL, *lname = NULL;
2101: size_t siglen = 0, keylen = 0;
2102: int i, r, success = 0;
2103:
2104: if (authctxt->ktypes == NULL) {
1.344 dtucker 2105: authctxt->oktypes = xstrdup(options.hostbased_accepted_algos);
1.223 djm 2106: authctxt->ktypes = authctxt->oktypes;
2107: }
1.213 djm 2108:
1.223 djm 2109: /*
1.344 dtucker 2110: * Work through each listed type pattern in HostbasedAcceptedAlgorithms,
1.223 djm 2111: * trying each hostkey that matches the type in turn.
2112: */
2113: for (;;) {
2114: if (authctxt->active_ktype == NULL)
2115: authctxt->active_ktype = strsep(&authctxt->ktypes, ",");
2116: if (authctxt->active_ktype == NULL ||
2117: *authctxt->active_ktype == '\0')
2118: break;
1.331 djm 2119: debug3_f("trying key type %s", authctxt->active_ktype);
1.68 markus 2120:
1.223 djm 2121: /* check for a useful key */
2122: private = NULL;
2123: for (i = 0; i < authctxt->sensitive->nkeys; i++) {
2124: if (authctxt->sensitive->keys[i] == NULL ||
2125: authctxt->sensitive->keys[i]->type == KEY_UNSPEC)
2126: continue;
2127: if (match_pattern_list(
2128: sshkey_ssh_name(authctxt->sensitive->keys[i]),
1.224 djm 2129: authctxt->active_ktype, 0) != 1)
1.223 djm 2130: continue;
1.68 markus 2131: /* we take and free the key */
1.223 djm 2132: private = authctxt->sensitive->keys[i];
2133: authctxt->sensitive->keys[i] = NULL;
1.68 markus 2134: break;
2135: }
1.223 djm 2136: /* Found one */
2137: if (private != NULL)
2138: break;
2139: /* No more keys of this type; advance */
2140: authctxt->active_ktype = NULL;
1.68 markus 2141: }
1.223 djm 2142: if (private == NULL) {
2143: free(authctxt->oktypes);
2144: authctxt->oktypes = authctxt->ktypes = NULL;
2145: authctxt->active_ktype = NULL;
1.109 markus 2146: debug("No more client hostkeys for hostbased authentication.");
1.223 djm 2147: goto out;
1.68 markus 2148: }
1.211 djm 2149:
1.223 djm 2150: if ((fp = sshkey_fingerprint(private, options.fingerprint_hash,
2151: SSH_FP_DEFAULT)) == NULL) {
1.331 djm 2152: error_f("sshkey_fingerprint failed");
1.223 djm 2153: goto out;
1.68 markus 2154: }
1.331 djm 2155: debug_f("trying hostkey %s %s", sshkey_ssh_name(private), fp);
1.211 djm 2156:
1.84 markus 2157: /* figure out a name for the client host */
1.295 djm 2158: lname = get_local_name(ssh_packet_get_connection_in(ssh));
2159: if (lname == NULL) {
1.331 djm 2160: error_f("cannot get local ipaddr/name");
1.223 djm 2161: goto out;
1.84 markus 2162: }
1.223 djm 2163:
2164: /* XXX sshbuf_put_stringf? */
2165: xasprintf(&chost, "%s.", lname);
1.331 djm 2166: debug2_f("chost %s", chost);
1.84 markus 2167:
1.68 markus 2168: /* construct data */
1.223 djm 2169: if ((b = sshbuf_new()) == NULL) {
1.331 djm 2170: error_f("sshbuf_new failed");
1.223 djm 2171: goto out;
2172: }
2173: if ((r = sshkey_to_blob(private, &keyblob, &keylen)) != 0) {
1.331 djm 2174: error_fr(r, "sshkey_to_blob");
1.223 djm 2175: goto out;
2176: }
1.346 djm 2177: if ((r = sshbuf_put_stringb(b, ssh->kex->session_id)) != 0 ||
1.223 djm 2178: (r = sshbuf_put_u8(b, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
2179: (r = sshbuf_put_cstring(b, authctxt->server_user)) != 0 ||
1.267 djm 2180: (r = sshbuf_put_cstring(b, authctxt->service)) != 0 ||
1.223 djm 2181: (r = sshbuf_put_cstring(b, authctxt->method->name)) != 0 ||
1.343 djm 2182: (r = sshbuf_put_cstring(b, authctxt->active_ktype)) != 0 ||
1.223 djm 2183: (r = sshbuf_put_string(b, keyblob, keylen)) != 0 ||
2184: (r = sshbuf_put_cstring(b, chost)) != 0 ||
2185: (r = sshbuf_put_cstring(b, authctxt->local_user)) != 0) {
1.331 djm 2186: error_fr(r, "buffer error");
1.223 djm 2187: goto out;
2188: }
2189:
1.68 markus 2190: #ifdef DEBUG_PK
1.223 djm 2191: sshbuf_dump(b, stderr);
1.68 markus 2192: #endif
1.294 djm 2193: if ((r = ssh_keysign(ssh, private, &sig, &siglen,
2194: sshbuf_ptr(b), sshbuf_len(b))) != 0) {
1.223 djm 2195: error("sign using hostkey %s %s failed",
2196: sshkey_ssh_name(private), fp);
2197: goto out;
2198: }
2199: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
2200: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
2201: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
2202: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1.343 djm 2203: (r = sshpkt_put_cstring(ssh, authctxt->active_ktype)) != 0 ||
1.223 djm 2204: (r = sshpkt_put_string(ssh, keyblob, keylen)) != 0 ||
2205: (r = sshpkt_put_cstring(ssh, chost)) != 0 ||
2206: (r = sshpkt_put_cstring(ssh, authctxt->local_user)) != 0 ||
2207: (r = sshpkt_put_string(ssh, sig, siglen)) != 0 ||
2208: (r = sshpkt_send(ssh)) != 0) {
1.331 djm 2209: error_fr(r, "packet error");
1.223 djm 2210: goto out;
2211: }
2212: success = 1;
2213:
2214: out:
1.278 markus 2215: if (sig != NULL)
2216: freezero(sig, siglen);
1.223 djm 2217: free(keyblob);
2218: free(lname);
2219: free(fp);
1.197 djm 2220: free(chost);
1.223 djm 2221: sshkey_free(private);
2222: sshbuf_free(b);
1.68 markus 2223:
1.223 djm 2224: return success;
1.23 markus 2225: }
1.170 djm 2226:
1.20 markus 2227: /* find auth method */
2228:
2229: /*
2230: * given auth method name, if configurable options permit this method fill
2231: * in auth_ident field and return true, otherwise return false.
2232: */
1.76 itojun 2233: static int
1.20 markus 2234: authmethod_is_enabled(Authmethod *method)
2235: {
2236: if (method == NULL)
2237: return 0;
2238: /* return false if options indicate this method is disabled */
2239: if (method->enabled == NULL || *method->enabled == 0)
2240: return 0;
2241: /* return false if batch mode is enabled but method needs interactive mode */
2242: if (method->batch_flag != NULL && *method->batch_flag != 0)
2243: return 0;
2244: return 1;
2245: }
2246:
1.76 itojun 2247: static Authmethod *
1.20 markus 2248: authmethod_lookup(const char *name)
1.1 markus 2249: {
1.20 markus 2250: Authmethod *method = NULL;
2251: if (name != NULL)
2252: for (method = authmethods; method->name != NULL; method++)
2253: if (strcmp(name, method->name) == 0)
2254: return method;
2255: debug2("Unrecognized authentication method name: %s", name ? name : "NULL");
2256: return NULL;
2257: }
1.1 markus 2258:
1.53 markus 2259: /* XXX internal state */
2260: static Authmethod *current = NULL;
2261: static char *supported = NULL;
2262: static char *preferred = NULL;
1.105 deraadt 2263:
1.20 markus 2264: /*
2265: * Given the authentication method list sent by the server, return the
2266: * next method we should try. If the server initially sends a nil list,
1.67 markus 2267: * use a built-in default list.
1.41 stevesk 2268: */
1.76 itojun 2269: static Authmethod *
1.20 markus 2270: authmethod_get(char *authlist)
2271: {
1.53 markus 2272: char *name = NULL;
1.97 markus 2273: u_int next;
1.41 stevesk 2274:
1.20 markus 2275: /* Use a suitable default if we're passed a nil list. */
2276: if (authlist == NULL || strlen(authlist) == 0)
1.53 markus 2277: authlist = options.preferred_authentications;
1.20 markus 2278:
1.53 markus 2279: if (supported == NULL || strcmp(authlist, supported) != 0) {
2280: debug3("start over, passed a different list %s", authlist);
1.197 djm 2281: free(supported);
1.53 markus 2282: supported = xstrdup(authlist);
2283: preferred = options.preferred_authentications;
2284: debug3("preferred %s", preferred);
2285: current = NULL;
2286: } else if (current != NULL && authmethod_is_enabled(current))
2287: return current;
1.20 markus 2288:
1.53 markus 2289: for (;;) {
2290: if ((name = match_list(preferred, supported, &next)) == NULL) {
1.109 markus 2291: debug("No more authentication methods to try.");
1.53 markus 2292: current = NULL;
2293: return NULL;
2294: }
2295: preferred += next;
1.23 markus 2296: debug3("authmethod_lookup %s", name);
1.53 markus 2297: debug3("remaining preferred: %s", preferred);
2298: if ((current = authmethod_lookup(name)) != NULL &&
2299: authmethod_is_enabled(current)) {
1.23 markus 2300: debug3("authmethod_is_enabled %s", name);
1.109 markus 2301: debug("Next authentication method: %s", name);
1.197 djm 2302: free(name);
1.53 markus 2303: return current;
1.23 markus 2304: }
1.198 dtucker 2305: free(name);
1.1 markus 2306: }
1.53 markus 2307: }
1.1 markus 2308:
1.79 stevesk 2309: static char *
1.53 markus 2310: authmethods_get(void)
2311: {
2312: Authmethod *method = NULL;
1.278 markus 2313: struct sshbuf *b;
1.93 markus 2314: char *list;
1.278 markus 2315: int r;
1.27 provos 2316:
1.278 markus 2317: if ((b = sshbuf_new()) == NULL)
1.331 djm 2318: fatal_f("sshbuf_new failed");
1.53 markus 2319: for (method = authmethods; method->name != NULL; method++) {
2320: if (authmethod_is_enabled(method)) {
1.278 markus 2321: if ((r = sshbuf_putf(b, "%s%s",
2322: sshbuf_len(b) ? "," : "", method->name)) != 0)
1.331 djm 2323: fatal_fr(r, "buffer error");
1.53 markus 2324: }
2325: }
1.278 markus 2326: if ((list = sshbuf_dup_string(b)) == NULL)
1.331 djm 2327: fatal_f("sshbuf_dup_string failed");
1.278 markus 2328: sshbuf_free(b);
1.93 markus 2329: return list;
1.1 markus 2330: }
![[BACK]](/icons/back.gif){kind=icon}
Return to sshconnect2.c CVS log ![[TXT]](/icons/text.gif){kind=icon}
![[DIR]](/icons/dir.gif){kind=icon}
Up to [local] / src / usr.bin / ssh