Annotation of src/usr.bin/ssh/sshconnect2.c, Revision 1.336
1.336 ! djm 1: /* $OpenBSD: sshconnect2.c,v 1.335 2020/11/13 04:53:12 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:
1.32 markus 87: u_char *session_id2 = NULL;
1.120 markus 88: u_int session_id2_len = 0;
1.1 markus 89:
1.61 markus 90: char *xxx_host;
91: struct sockaddr *xxx_hostaddr;
92:
1.76 itojun 93: static int
1.259 markus 94: verify_host_key_callback(struct sshkey *hostkey, struct ssh *ssh)
1.61 markus 95: {
1.329 djm 96: if (verify_host_key(xxx_host, xxx_hostaddr, hostkey) == -1)
1.83 markus 97: fatal("Host key verification failed.");
1.61 markus 98: return 0;
99: }
100:
1.326 djm 101: /* Returns the first item from a comma-separated algorithm list */
102: static char *
103: first_alg(const char *algs)
104: {
105: char *ret, *cp;
106:
107: ret = xstrdup(algs);
108: if ((cp = strchr(ret, ',')) != NULL)
109: *cp = '\0';
110: return ret;
111: }
112:
1.186 djm 113: static char *
114: order_hostkeyalgs(char *host, struct sockaddr *hostaddr, u_short port)
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++)
127: load_hostkeys(hostkeys, hostname, options.user_hostfiles[i]);
128: for (i = 0; i < options.num_system_hostfiles; i++)
129: load_hostkeys(hostkeys, hostname, options.system_hostfiles[i]);
1.186 djm 130:
1.326 djm 131: /*
132: * If a plain public key exists that matches the type of the best
133: * preference HostkeyAlgorithms, then use the whole list as is.
134: * Note that we ignore whether the best preference algorithm is a
135: * certificate type, as sshconnect.c will downgrade certs to
136: * plain keys if necessary.
137: */
138: best = first_alg(options.hostkeyalgorithms);
139: if (lookup_key_in_hostkeys_by_type(hostkeys,
1.328 djm 140: sshkey_type_plain(sshkey_type_from_name(best)),
141: sshkey_ecdsa_nid_from_name(best), NULL)) {
1.331 djm 142: debug3_f("have matching best-preference key type %s, "
143: "using HostkeyAlgorithms verbatim", best);
1.326 djm 144: ret = xstrdup(options.hostkeyalgorithms);
145: goto out;
146: }
147:
148: /*
149: * Otherwise, prefer the host key algorithms that match known keys
150: * while keeping the ordering of HostkeyAlgorithms as much as possible.
151: */
1.320 djm 152: oavail = avail = xstrdup(options.hostkeyalgorithms);
1.186 djm 153: maxlen = strlen(avail) + 1;
154: first = xmalloc(maxlen);
155: last = xmalloc(maxlen);
156: *first = *last = '\0';
157:
158: #define ALG_APPEND(to, from) \
159: do { \
160: if (*to != '\0') \
161: strlcat(to, ",", maxlen); \
162: strlcat(to, from, maxlen); \
163: } while (0)
164:
165: while ((alg = strsep(&avail, ",")) && *alg != '\0') {
1.214 djm 166: if ((ktype = sshkey_type_from_name(alg)) == KEY_UNSPEC)
1.331 djm 167: fatal_f("unknown alg %s", alg);
1.322 djm 168: /*
169: * If we have a @cert-authority marker in known_hosts then
170: * prefer all certificate algorithms.
171: */
172: if (sshkey_type_is_cert(ktype) &&
173: lookup_marker_in_hostkeys(hostkeys, MRK_CA)) {
174: ALG_APPEND(first, alg);
175: continue;
176: }
177: /* If the key appears in known_hosts then prefer it */
1.186 djm 178: if (lookup_key_in_hostkeys_by_type(hostkeys,
1.328 djm 179: sshkey_type_plain(ktype),
180: sshkey_ecdsa_nid_from_name(alg), NULL)) {
1.186 djm 181: ALG_APPEND(first, alg);
1.322 djm 182: continue;
183: }
184: /* Otherwise, put it last */
185: ALG_APPEND(last, alg);
1.186 djm 186: }
187: #undef ALG_APPEND
1.216 djm 188: xasprintf(&ret, "%s%s%s", first,
189: (*first == '\0' || *last == '\0') ? "" : ",", last);
1.186 djm 190: if (*first != '\0')
1.331 djm 191: debug3_f("prefer hostkeyalgs: %s", first);
1.186 djm 192:
1.326 djm 193: out:
194: free(best);
1.197 djm 195: free(first);
196: free(last);
197: free(hostname);
198: free(oavail);
1.186 djm 199: free_hostkeys(hostkeys);
200:
201: return ret;
202: }
203:
1.1 markus 204: void
1.291 djm 205: ssh_kex2(struct ssh *ssh, char *host, struct sockaddr *hostaddr, u_short port)
1.22 provos 206: {
1.205 markus 207: char *myproposal[PROPOSAL_MAX] = { KEX_CLIENT };
1.275 djm 208: char *s, *all_key;
1.320 djm 209: int r, use_known_hosts_order = 0;
1.61 markus 210:
211: xxx_host = host;
212: xxx_hostaddr = hostaddr;
1.22 provos 213:
1.320 djm 214: /*
215: * If the user has not specified HostkeyAlgorithms, or has only
216: * appended or removed algorithms from that list then prefer algorithms
217: * that are in the list that are supported by known_hosts keys.
218: */
219: if (options.hostkeyalgorithms == NULL ||
220: options.hostkeyalgorithms[0] == '-' ||
221: options.hostkeyalgorithms[0] == '+')
222: use_known_hosts_order = 1;
223:
224: /* Expand or fill in HostkeyAlgorithms */
225: all_key = sshkey_alg_list(0, 0, 1, ',');
1.333 djm 226: if ((r = kex_assemble_names(&options.hostkeyalgorithms,
227: kex_default_pk_alg(), all_key)) != 0)
228: fatal_fr(r, "kex_assemble_namelist");
1.320 djm 229: free(all_key);
230:
1.231 markus 231: if ((s = kex_names_cat(options.kex_algorithms, "ext-info-c")) == NULL)
1.331 djm 232: fatal_f("kex_names_cat");
1.284 djm 233: myproposal[PROPOSAL_KEX_ALGS] = compat_kex_proposal(s);
1.60 stevesk 234: myproposal[PROPOSAL_ENC_ALGS_CTOS] =
1.284 djm 235: compat_cipher_proposal(options.ciphers);
1.60 stevesk 236: myproposal[PROPOSAL_ENC_ALGS_STOC] =
1.284 djm 237: compat_cipher_proposal(options.ciphers);
1.245 dtucker 238: myproposal[PROPOSAL_COMP_ALGS_CTOS] =
1.318 dtucker 239: myproposal[PROPOSAL_COMP_ALGS_STOC] =
240: (char *)compression_alg_list(options.compression);
1.226 djm 241: myproposal[PROPOSAL_MAC_ALGS_CTOS] =
242: myproposal[PROPOSAL_MAC_ALGS_STOC] = options.macs;
1.320 djm 243: if (use_known_hosts_order) {
244: /* Query known_hosts and prefer algorithms that appear there */
1.88 deraadt 245: myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] =
1.320 djm 246: compat_pkalg_proposal(
247: order_hostkeyalgs(host, hostaddr, port));
1.226 djm 248: } else {
1.320 djm 249: /* Use specified HostkeyAlgorithms exactly */
1.186 djm 250: myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] =
1.320 djm 251: compat_pkalg_proposal(options.hostkeyalgorithms);
1.186 djm 252: }
1.115 markus 253:
1.196 dtucker 254: if (options.rekey_limit || options.rekey_interval)
1.294 djm 255: ssh_packet_set_rekey_limits(ssh, options.rekey_limit,
1.254 dtucker 256: options.rekey_interval);
1.22 provos 257:
1.65 markus 258: /* start key exchange */
1.291 djm 259: if ((r = kex_setup(ssh, myproposal)) != 0)
1.331 djm 260: fatal_r(r, "kex_setup");
1.207 markus 261: #ifdef WITH_OPENSSL
1.301 djm 262: ssh->kex->kex[KEX_DH_GRP1_SHA1] = kex_gen_client;
263: ssh->kex->kex[KEX_DH_GRP14_SHA1] = kex_gen_client;
264: ssh->kex->kex[KEX_DH_GRP14_SHA256] = kex_gen_client;
265: ssh->kex->kex[KEX_DH_GRP16_SHA512] = kex_gen_client;
266: ssh->kex->kex[KEX_DH_GRP18_SHA512] = kex_gen_client;
1.291 djm 267: ssh->kex->kex[KEX_DH_GEX_SHA1] = kexgex_client;
268: ssh->kex->kex[KEX_DH_GEX_SHA256] = kexgex_client;
1.301 djm 269: ssh->kex->kex[KEX_ECDH_SHA2] = kex_gen_client;
1.207 markus 270: #endif
1.301 djm 271: ssh->kex->kex[KEX_C25519_SHA256] = kex_gen_client;
272: ssh->kex->kex[KEX_KEM_SNTRUP4591761X25519_SHA512] = kex_gen_client;
1.291 djm 273: ssh->kex->verify_host_key=&verify_host_key_callback;
1.22 provos 274:
1.291 djm 275: ssh_dispatch_run_fatal(ssh, DISPATCH_BLOCK, &ssh->kex->done);
1.173 andreas 276:
1.231 markus 277: /* remove ext-info from the KEX proposals for rekeying */
278: myproposal[PROPOSAL_KEX_ALGS] =
1.284 djm 279: compat_kex_proposal(options.kex_algorithms);
1.291 djm 280: if ((r = kex_prop2buf(ssh->kex->my, myproposal)) != 0)
1.331 djm 281: fatal_r(r, "kex_prop2buf");
1.62 markus 282:
1.291 djm 283: session_id2 = ssh->kex->session_id;
284: session_id2_len = ssh->kex->session_id_len;
1.22 provos 285:
286: #ifdef DEBUG_KEXDH
287: /* send 1st encrypted/maced/compressed message */
1.278 markus 288: if ((r = sshpkt_start(ssh, SSH2_MSG_IGNORE)) != 0 ||
289: (r = sshpkt_put_cstring(ssh, "markus")) != 0 ||
1.280 markus 290: (r = sshpkt_send(ssh)) != 0 ||
291: (r = ssh_packet_write_wait(ssh)) != 0)
1.331 djm 292: fatal_fr(r, "send packet");
1.22 provos 293: #endif
1.1 markus 294: }
1.11 markus 295:
1.1 markus 296: /*
297: * Authenticate user
298: */
1.20 markus 299:
1.214 djm 300: typedef struct cauthctxt Authctxt;
301: typedef struct cauthmethod Authmethod;
1.117 markus 302: typedef struct identity Identity;
303: typedef struct idlist Idlist;
1.20 markus 304:
1.117 markus 305: struct identity {
306: TAILQ_ENTRY(identity) next;
1.214 djm 307: int agent_fd; /* >=0 if agent supports key */
308: struct sshkey *key; /* public/private key */
1.117 markus 309: char *filename; /* comment for agent-only keys */
310: int tried;
311: int isprivate; /* key points to the private key */
1.191 dtucker 312: int userprovided;
1.117 markus 313: };
314: TAILQ_HEAD(idlist, identity);
1.20 markus 315:
1.214 djm 316: struct cauthctxt {
1.20 markus 317: const char *server_user;
1.68 markus 318: const char *local_user;
1.20 markus 319: const char *host;
320: const char *service;
1.214 djm 321: struct cauthmethod *method;
1.183 djm 322: sig_atomic_t success;
1.51 markus 323: char *authlist;
1.302 djm 324: #ifdef GSSAPI
325: /* gssapi */
326: gss_OID_set gss_supported_mechs;
327: u_int mech_tried;
328: #endif
1.68 markus 329: /* pubkey */
1.214 djm 330: struct idlist keys;
331: int agent_fd;
1.68 markus 332: /* hostbased */
1.100 markus 333: Sensitive *sensitive;
1.223 djm 334: char *oktypes, *ktypes;
335: const char *active_ktype;
1.82 markus 336: /* kbd-interactive */
337: int info_req_seen;
1.292 djm 338: int attempt_kbdint;
339: /* password */
340: int attempt_passwd;
1.121 markus 341: /* generic */
342: void *methoddata;
1.20 markus 343: };
1.214 djm 344:
345: struct cauthmethod {
1.20 markus 346: char *name; /* string to compare against server's list */
1.295 djm 347: int (*userauth)(struct ssh *ssh);
348: void (*cleanup)(struct ssh *ssh);
1.20 markus 349: int *enabled; /* flag in option struct that enables method */
350: int *batch_flag; /* flag in option struct that disables method */
351: };
352:
1.302 djm 353: static int input_userauth_service_accept(int, u_int32_t, struct ssh *);
354: static int input_userauth_ext_info(int, u_int32_t, struct ssh *);
355: static int input_userauth_success(int, u_int32_t, struct ssh *);
356: static int input_userauth_failure(int, u_int32_t, struct ssh *);
357: static int input_userauth_banner(int, u_int32_t, struct ssh *);
358: static int input_userauth_error(int, u_int32_t, struct ssh *);
359: static int input_userauth_info_req(int, u_int32_t, struct ssh *);
360: static int input_userauth_pk_ok(int, u_int32_t, struct ssh *);
361: static int input_userauth_passwd_changereq(int, u_int32_t, struct ssh *);
362:
363: static int userauth_none(struct ssh *);
364: static int userauth_pubkey(struct ssh *);
365: static int userauth_passwd(struct ssh *);
366: static int userauth_kbdint(struct ssh *);
367: static int userauth_hostbased(struct ssh *);
1.20 markus 368:
1.121 markus 369: #ifdef GSSAPI
1.302 djm 370: static int userauth_gssapi(struct ssh *);
371: static void userauth_gssapi_cleanup(struct ssh *);
372: static int input_gssapi_response(int type, u_int32_t, struct ssh *);
373: static int input_gssapi_token(int type, u_int32_t, struct ssh *);
374: static int input_gssapi_error(int, u_int32_t, struct ssh *);
375: static int input_gssapi_errtok(int, u_int32_t, struct ssh *);
1.121 markus 376: #endif
377:
1.295 djm 378: void userauth(struct ssh *, char *);
1.51 markus 379:
1.303 djm 380: static void pubkey_cleanup(struct ssh *);
1.295 djm 381: static int sign_and_send_pubkey(struct ssh *ssh, Identity *);
1.117 markus 382: static void pubkey_prepare(Authctxt *);
1.251 djm 383: static void pubkey_reset(Authctxt *);
1.259 markus 384: static struct sshkey *load_identity_file(Identity *);
1.76 itojun 385:
386: static Authmethod *authmethod_get(char *authlist);
387: static Authmethod *authmethod_lookup(const char *name);
388: static char *authmethods_get(void);
1.20 markus 389:
390: Authmethod authmethods[] = {
1.121 markus 391: #ifdef GSSAPI
1.132 markus 392: {"gssapi-with-mic",
1.121 markus 393: userauth_gssapi,
1.302 djm 394: userauth_gssapi_cleanup,
1.121 markus 395: &options.gss_authentication,
396: NULL},
397: #endif
1.81 markus 398: {"hostbased",
399: userauth_hostbased,
1.170 djm 400: NULL,
1.81 markus 401: &options.hostbased_authentication,
402: NULL},
1.20 markus 403: {"publickey",
404: userauth_pubkey,
1.303 djm 405: NULL,
1.28 markus 406: &options.pubkey_authentication,
1.20 markus 407: NULL},
1.81 markus 408: {"keyboard-interactive",
409: userauth_kbdint,
1.170 djm 410: NULL,
1.81 markus 411: &options.kbd_interactive_authentication,
412: &options.batch_mode},
1.20 markus 413: {"password",
414: userauth_passwd,
1.170 djm 415: NULL,
1.20 markus 416: &options.password_authentication,
1.23 markus 417: &options.batch_mode},
418: {"none",
419: userauth_none,
420: NULL,
1.170 djm 421: NULL,
1.23 markus 422: NULL},
1.170 djm 423: {NULL, NULL, NULL, NULL, NULL}
1.20 markus 424: };
425:
426: void
1.291 djm 427: ssh_userauth2(struct ssh *ssh, const char *local_user,
428: const char *server_user, char *host, Sensitive *sensitive)
1.20 markus 429: {
430: Authctxt authctxt;
1.231 markus 431: int r;
1.39 markus 432:
1.73 markus 433: if (options.challenge_response_authentication)
1.39 markus 434: options.kbd_interactive_authentication = 1;
1.53 markus 435: if (options.preferred_authentications == NULL)
436: options.preferred_authentications = authmethods_get();
437:
1.20 markus 438: /* setup authentication context */
1.82 markus 439: memset(&authctxt, 0, sizeof(authctxt));
1.20 markus 440: authctxt.server_user = server_user;
1.68 markus 441: authctxt.local_user = local_user;
1.20 markus 442: authctxt.host = host;
443: authctxt.service = "ssh-connection"; /* service name */
444: authctxt.success = 0;
1.23 markus 445: authctxt.method = authmethod_lookup("none");
1.51 markus 446: authctxt.authlist = NULL;
1.121 markus 447: authctxt.methoddata = NULL;
1.100 markus 448: authctxt.sensitive = sensitive;
1.223 djm 449: authctxt.active_ktype = authctxt.oktypes = authctxt.ktypes = NULL;
1.82 markus 450: authctxt.info_req_seen = 0;
1.292 djm 451: authctxt.attempt_kbdint = 0;
452: authctxt.attempt_passwd = 0;
1.302 djm 453: #if GSSAPI
454: authctxt.gss_supported_mechs = NULL;
455: authctxt.mech_tried = 0;
456: #endif
1.215 djm 457: authctxt.agent_fd = -1;
1.289 djm 458: pubkey_prepare(&authctxt);
1.291 djm 459: if (authctxt.method == NULL) {
1.331 djm 460: fatal_f("internal error: cannot send userauth none request");
1.291 djm 461: }
1.20 markus 462:
1.231 markus 463: if ((r = sshpkt_start(ssh, SSH2_MSG_SERVICE_REQUEST)) != 0 ||
464: (r = sshpkt_put_cstring(ssh, "ssh-userauth")) != 0 ||
465: (r = sshpkt_send(ssh)) != 0)
1.331 djm 466: fatal_fr(r, "send packet");
1.231 markus 467:
1.260 markus 468: ssh->authctxt = &authctxt;
1.231 markus 469: ssh_dispatch_init(ssh, &input_userauth_error);
470: ssh_dispatch_set(ssh, SSH2_MSG_EXT_INFO, &input_userauth_ext_info);
471: ssh_dispatch_set(ssh, SSH2_MSG_SERVICE_ACCEPT, &input_userauth_service_accept);
1.263 markus 472: ssh_dispatch_run_fatal(ssh, DISPATCH_BLOCK, &authctxt.success); /* loop until success */
1.303 djm 473: pubkey_cleanup(ssh);
1.260 markus 474: ssh->authctxt = NULL;
1.20 markus 475:
1.231 markus 476: ssh_dispatch_range(ssh, SSH2_MSG_USERAUTH_MIN, SSH2_MSG_USERAUTH_MAX, NULL);
1.119 markus 477:
1.248 dtucker 478: if (!authctxt.success)
479: fatal("Authentication failed.");
1.109 markus 480: debug("Authentication succeeded (%s).", authctxt.method->name);
1.20 markus 481: }
1.119 markus 482:
1.231 markus 483: /* ARGSUSED */
1.302 djm 484: static int
1.261 markus 485: input_userauth_service_accept(int type, u_int32_t seq, struct ssh *ssh)
1.231 markus 486: {
487: int r;
488:
489: if (ssh_packet_remaining(ssh) > 0) {
490: char *reply;
491:
492: if ((r = sshpkt_get_cstring(ssh, &reply, NULL)) != 0)
493: goto out;
494: debug2("service_accept: %s", reply);
495: free(reply);
496: } else {
497: debug2("buggy server: service_accept w/o service");
498: }
499: if ((r = sshpkt_get_end(ssh)) != 0)
500: goto out;
501: debug("SSH2_MSG_SERVICE_ACCEPT received");
502:
503: /* initial userauth request */
1.295 djm 504: userauth_none(ssh);
1.231 markus 505:
506: ssh_dispatch_set(ssh, SSH2_MSG_EXT_INFO, &input_userauth_error);
507: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_SUCCESS, &input_userauth_success);
508: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_FAILURE, &input_userauth_failure);
509: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_BANNER, &input_userauth_banner);
510: r = 0;
511: out:
512: return r;
513: }
514:
515: /* ARGSUSED */
1.302 djm 516: static int
1.261 markus 517: input_userauth_ext_info(int type, u_int32_t seqnr, struct ssh *ssh)
1.231 markus 518: {
1.261 markus 519: return kex_input_ext_info(type, seqnr, ssh);
1.231 markus 520: }
521:
1.20 markus 522: void
1.295 djm 523: userauth(struct ssh *ssh, char *authlist)
1.51 markus 524: {
1.295 djm 525: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.278 markus 526:
1.170 djm 527: if (authctxt->method != NULL && authctxt->method->cleanup != NULL)
1.295 djm 528: authctxt->method->cleanup(ssh);
1.170 djm 529:
1.197 djm 530: free(authctxt->methoddata);
531: authctxt->methoddata = NULL;
1.51 markus 532: if (authlist == NULL) {
533: authlist = authctxt->authlist;
534: } else {
1.197 djm 535: free(authctxt->authlist);
1.51 markus 536: authctxt->authlist = authlist;
537: }
538: for (;;) {
539: Authmethod *method = authmethod_get(authlist);
540: if (method == NULL)
1.264 dtucker 541: fatal("%s@%s: Permission denied (%s).",
542: authctxt->server_user, authctxt->host, authlist);
1.51 markus 543: authctxt->method = method;
1.119 markus 544:
545: /* reset the per method handler */
1.278 markus 546: ssh_dispatch_range(ssh, SSH2_MSG_USERAUTH_PER_METHOD_MIN,
1.119 markus 547: SSH2_MSG_USERAUTH_PER_METHOD_MAX, NULL);
548:
549: /* and try new method */
1.295 djm 550: if (method->userauth(ssh) != 0) {
1.51 markus 551: debug2("we sent a %s packet, wait for reply", method->name);
552: break;
553: } else {
554: debug2("we did not send a packet, disable method");
555: method->enabled = NULL;
556: }
557: }
558: }
1.105 deraadt 559:
1.169 djm 560: /* ARGSUSED */
1.302 djm 561: static int
1.261 markus 562: input_userauth_error(int type, u_int32_t seq, struct ssh *ssh)
1.20 markus 563: {
1.331 djm 564: fatal_f("bad message during authentication: type %d", type);
1.218 markus 565: return 0;
1.35 markus 566: }
1.105 deraadt 567:
1.169 djm 568: /* ARGSUSED */
1.302 djm 569: static int
1.261 markus 570: input_userauth_banner(int type, u_int32_t seq, struct ssh *ssh)
1.35 markus 571: {
1.295 djm 572: char *msg = NULL;
1.294 djm 573: size_t len;
574: int r;
1.126 deraadt 575:
1.331 djm 576: debug3_f("entering");
1.294 djm 577: if ((r = sshpkt_get_cstring(ssh, &msg, &len)) != 0 ||
1.295 djm 578: (r = sshpkt_get_cstring(ssh, NULL, NULL)) != 0)
1.294 djm 579: goto out;
1.246 djm 580: if (len > 0 && options.log_level >= SYSLOG_LEVEL_INFO)
581: fmprintf(stderr, "%s", msg);
1.294 djm 582: r = 0;
583: out:
1.246 djm 584: free(msg);
1.294 djm 585: return r;
1.20 markus 586: }
1.105 deraadt 587:
1.169 djm 588: /* ARGSUSED */
1.302 djm 589: static int
1.261 markus 590: input_userauth_success(int type, u_int32_t seq, struct ssh *ssh)
1.20 markus 591: {
1.260 markus 592: Authctxt *authctxt = ssh->authctxt;
1.172 djm 593:
1.20 markus 594: if (authctxt == NULL)
1.331 djm 595: fatal_f("no authentication context");
1.197 djm 596: free(authctxt->authlist);
597: authctxt->authlist = NULL;
1.172 djm 598: if (authctxt->method != NULL && authctxt->method->cleanup != NULL)
1.295 djm 599: authctxt->method->cleanup(ssh);
1.197 djm 600: free(authctxt->methoddata);
601: authctxt->methoddata = NULL;
1.20 markus 602: authctxt->success = 1; /* break out */
1.218 markus 603: return 0;
1.20 markus 604: }
1.105 deraadt 605:
1.302 djm 606: #if 0
607: static int
1.261 markus 608: input_userauth_success_unexpected(int type, u_int32_t seq, struct ssh *ssh)
1.172 djm 609: {
1.260 markus 610: Authctxt *authctxt = ssh->authctxt;
1.172 djm 611:
612: if (authctxt == NULL)
1.331 djm 613: fatal_f("no authentication context");
1.172 djm 614:
615: fatal("Unexpected authentication success during %s.",
616: authctxt->method->name);
1.218 markus 617: return 0;
1.172 djm 618: }
1.302 djm 619: #endif
1.172 djm 620:
1.169 djm 621: /* ARGSUSED */
1.302 djm 622: static int
1.261 markus 623: input_userauth_failure(int type, u_int32_t seq, struct ssh *ssh)
1.20 markus 624: {
1.260 markus 625: Authctxt *authctxt = ssh->authctxt;
1.20 markus 626: char *authlist = NULL;
1.278 markus 627: u_char partial;
1.20 markus 628:
629: if (authctxt == NULL)
630: fatal("input_userauth_failure: no authentication context");
631:
1.307 dtucker 632: if (sshpkt_get_cstring(ssh, &authlist, NULL) != 0 ||
633: sshpkt_get_u8(ssh, &partial) != 0 ||
634: sshpkt_get_end(ssh) != 0)
1.278 markus 635: goto out;
1.20 markus 636:
1.193 markus 637: if (partial != 0) {
1.247 dtucker 638: verbose("Authenticated with partial success.");
1.193 markus 639: /* reset state */
1.251 djm 640: pubkey_reset(authctxt);
1.193 markus 641: }
1.109 markus 642: debug("Authentications that can continue: %s", authlist);
1.20 markus 643:
1.295 djm 644: userauth(ssh, authlist);
1.278 markus 645: authlist = NULL;
646: out:
647: free(authlist);
1.218 markus 648: return 0;
1.51 markus 649: }
1.169 djm 650:
1.287 djm 651: /*
652: * Format an identity for logging including filename, key type, fingerprint
653: * and location (agent, etc.). Caller must free.
654: */
655: static char *
656: format_identity(Identity *id)
657: {
658: char *fp = NULL, *ret = NULL;
1.309 djm 659: const char *note = "";
1.287 djm 660:
661: if (id->key != NULL) {
662: fp = sshkey_fingerprint(id->key, options.fingerprint_hash,
663: SSH_FP_DEFAULT);
664: }
1.309 djm 665: if (id->key) {
666: if ((id->key->flags & SSHKEY_FLAG_EXT) != 0)
667: note = " token";
1.311 markus 668: else if (sshkey_is_sk(id->key))
1.319 naddy 669: note = " authenticator";
1.309 djm 670: }
1.287 djm 671: xasprintf(&ret, "%s %s%s%s%s%s%s",
672: id->filename,
673: id->key ? sshkey_type(id->key) : "", id->key ? " " : "",
674: fp ? fp : "",
1.309 djm 675: id->userprovided ? " explicit" : "", note,
1.287 djm 676: id->agent_fd != -1 ? " agent" : "");
677: free(fp);
678: return ret;
679: }
680:
1.169 djm 681: /* ARGSUSED */
1.302 djm 682: static int
1.261 markus 683: input_userauth_pk_ok(int type, u_int32_t seq, struct ssh *ssh)
1.51 markus 684: {
1.260 markus 685: Authctxt *authctxt = ssh->authctxt;
1.259 markus 686: struct sshkey *key = NULL;
1.117 markus 687: Identity *id = NULL;
1.287 djm 688: int pktype, found = 0, sent = 0;
1.278 markus 689: size_t blen;
1.287 djm 690: char *pkalg = NULL, *fp = NULL, *ident = NULL;
1.278 markus 691: u_char *pkblob = NULL;
692: int r;
1.51 markus 693:
694: if (authctxt == NULL)
695: fatal("input_userauth_pk_ok: no authentication context");
1.267 djm 696:
1.278 markus 697: if ((r = sshpkt_get_cstring(ssh, &pkalg, NULL)) != 0 ||
698: (r = sshpkt_get_string(ssh, &pkblob, &blen)) != 0 ||
699: (r = sshpkt_get_end(ssh)) != 0)
700: goto done;
1.51 markus 701:
1.278 markus 702: if ((pktype = sshkey_type_from_name(pkalg)) == KEY_UNSPEC) {
1.331 djm 703: debug_f("server sent unknown pkalg %s", pkalg);
1.117 markus 704: goto done;
705: }
1.278 markus 706: if ((r = sshkey_from_blob(pkblob, blen, &key)) != 0) {
1.331 djm 707: debug_r(r, "no key from blob. pkalg %s", pkalg);
1.117 markus 708: goto done;
709: }
710: if (key->type != pktype) {
711: error("input_userauth_pk_ok: type mismatch "
712: "for decoded key (received %d, expected %d)",
713: key->type, pktype);
714: goto done;
715: }
716:
1.127 markus 717: /*
718: * search keys in the reverse order, because last candidate has been
719: * moved to the end of the queue. this also avoids confusion by
720: * duplicate keys
721: */
1.136 henning 722: TAILQ_FOREACH_REVERSE(id, &authctxt->keys, idlist, next) {
1.278 markus 723: if (sshkey_equal(key, id->key)) {
1.287 djm 724: found = 1;
1.51 markus 725: break;
726: }
1.117 markus 727: }
1.287 djm 728: if (!found || id == NULL) {
729: fp = sshkey_fingerprint(key, options.fingerprint_hash,
730: SSH_FP_DEFAULT);
1.331 djm 731: error_f("server replied with unknown key: %s %s",
1.287 djm 732: sshkey_type(key), fp == NULL ? "<ERROR>" : fp);
733: goto done;
734: }
735: ident = format_identity(id);
736: debug("Server accepts key: %s", ident);
1.295 djm 737: sent = sign_and_send_pubkey(ssh, id);
1.278 markus 738: r = 0;
739: done:
740: sshkey_free(key);
1.287 djm 741: free(ident);
742: free(fp);
1.197 djm 743: free(pkalg);
744: free(pkblob);
1.51 markus 745:
1.106 deraadt 746: /* try another method if we did not send a packet */
1.278 markus 747: if (r == 0 && sent == 0)
1.295 djm 748: userauth(ssh, NULL);
1.278 markus 749: return r;
1.20 markus 750: }
1.121 markus 751:
752: #ifdef GSSAPI
1.302 djm 753: static int
1.295 djm 754: userauth_gssapi(struct ssh *ssh)
1.121 markus 755: {
1.295 djm 756: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.121 markus 757: Gssctxt *gssctxt = NULL;
758: OM_uint32 min;
1.278 markus 759: int r, ok = 0;
1.302 djm 760: gss_OID mech = NULL;
1.121 markus 761:
762: /* Try one GSSAPI method at a time, rather than sending them all at
763: * once. */
764:
1.302 djm 765: if (authctxt->gss_supported_mechs == NULL)
766: gss_indicate_mechs(&min, &authctxt->gss_supported_mechs);
1.121 markus 767:
1.302 djm 768: /* Check to see whether the mechanism is usable before we offer it */
769: while (authctxt->mech_tried < authctxt->gss_supported_mechs->count &&
770: !ok) {
771: mech = &authctxt->gss_supported_mechs->
772: elements[authctxt->mech_tried];
1.121 markus 773: /* My DER encoding requires length<128 */
1.302 djm 774: if (mech->length < 128 && ssh_gssapi_check_mechanism(&gssctxt,
775: mech, authctxt->host)) {
1.121 markus 776: ok = 1; /* Mechanism works */
777: } else {
1.302 djm 778: authctxt->mech_tried++;
1.121 markus 779: }
780: }
781:
1.302 djm 782: if (!ok || mech == NULL)
1.139 djm 783: return 0;
1.121 markus 784:
785: authctxt->methoddata=(void *)gssctxt;
786:
1.278 markus 787: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
788: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
789: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
790: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
791: (r = sshpkt_put_u32(ssh, 1)) != 0 ||
1.302 djm 792: (r = sshpkt_put_u32(ssh, (mech->length) + 2)) != 0 ||
1.278 markus 793: (r = sshpkt_put_u8(ssh, SSH_GSS_OIDTYPE)) != 0 ||
1.302 djm 794: (r = sshpkt_put_u8(ssh, mech->length)) != 0 ||
795: (r = sshpkt_put(ssh, mech->elements, mech->length)) != 0 ||
1.278 markus 796: (r = sshpkt_send(ssh)) != 0)
1.331 djm 797: fatal_fr(r, "send packet");
1.278 markus 798:
799: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_RESPONSE, &input_gssapi_response);
800: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_TOKEN, &input_gssapi_token);
801: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_ERROR, &input_gssapi_error);
802: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_ERRTOK, &input_gssapi_errtok);
1.121 markus 803:
1.302 djm 804: authctxt->mech_tried++; /* Move along to next candidate */
1.121 markus 805:
806: return 1;
807: }
808:
1.302 djm 809: static void
810: userauth_gssapi_cleanup(struct ssh *ssh)
811: {
812: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
813: Gssctxt *gssctxt = (Gssctxt *)authctxt->methoddata;
814:
815: ssh_gssapi_delete_ctx(&gssctxt);
816: authctxt->methoddata = NULL;
817:
818: free(authctxt->gss_supported_mechs);
819: authctxt->gss_supported_mechs = NULL;
820: }
821:
1.130 markus 822: static OM_uint32
1.262 djm 823: process_gssapi_token(struct ssh *ssh, gss_buffer_t recv_tok)
1.130 markus 824: {
1.260 markus 825: Authctxt *authctxt = ssh->authctxt;
1.130 markus 826: Gssctxt *gssctxt = authctxt->methoddata;
827: gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
1.142 djm 828: gss_buffer_desc mic = GSS_C_EMPTY_BUFFER;
829: gss_buffer_desc gssbuf;
1.132 markus 830: OM_uint32 status, ms, flags;
1.278 markus 831: int r;
1.133 djm 832:
1.130 markus 833: status = ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
1.132 markus 834: recv_tok, &send_tok, &flags);
1.130 markus 835:
836: if (send_tok.length > 0) {
1.278 markus 837: u_char type = GSS_ERROR(status) ?
838: SSH2_MSG_USERAUTH_GSSAPI_ERRTOK :
839: SSH2_MSG_USERAUTH_GSSAPI_TOKEN;
840:
841: if ((r = sshpkt_start(ssh, type)) != 0 ||
842: (r = sshpkt_put_string(ssh, send_tok.value,
843: send_tok.length)) != 0 ||
844: (r = sshpkt_send(ssh)) != 0)
1.331 djm 845: fatal_fr(r, "send %u packet", type);
1.133 djm 846:
1.130 markus 847: gss_release_buffer(&ms, &send_tok);
848: }
1.133 djm 849:
1.130 markus 850: if (status == GSS_S_COMPLETE) {
1.132 markus 851: /* send either complete or MIC, depending on mechanism */
852: if (!(flags & GSS_C_INTEG_FLAG)) {
1.278 markus 853: if ((r = sshpkt_start(ssh,
854: SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE)) != 0 ||
855: (r = sshpkt_send(ssh)) != 0)
1.331 djm 856: fatal_fr(r, "send completion");
1.132 markus 857: } else {
1.278 markus 858: struct sshbuf *b;
859:
860: if ((b = sshbuf_new()) == NULL)
1.331 djm 861: fatal_f("sshbuf_new failed");
1.278 markus 862: ssh_gssapi_buildmic(b, authctxt->server_user,
1.132 markus 863: authctxt->service, "gssapi-with-mic");
864:
1.278 markus 865: if ((gssbuf.value = sshbuf_mutable_ptr(b)) == NULL)
1.331 djm 866: fatal_f("sshbuf_mutable_ptr failed");
1.278 markus 867: gssbuf.length = sshbuf_len(b);
1.133 djm 868:
1.132 markus 869: status = ssh_gssapi_sign(gssctxt, &gssbuf, &mic);
1.133 djm 870:
1.132 markus 871: if (!GSS_ERROR(status)) {
1.278 markus 872: if ((r = sshpkt_start(ssh,
873: SSH2_MSG_USERAUTH_GSSAPI_MIC)) != 0 ||
874: (r = sshpkt_put_string(ssh, mic.value,
875: mic.length)) != 0 ||
876: (r = sshpkt_send(ssh)) != 0)
1.331 djm 877: fatal_fr(r, "send MIC");
1.132 markus 878: }
1.133 djm 879:
1.278 markus 880: sshbuf_free(b);
1.132 markus 881: gss_release_buffer(&ms, &mic);
1.133 djm 882: }
1.130 markus 883: }
1.133 djm 884:
1.130 markus 885: return status;
886: }
887:
1.169 djm 888: /* ARGSUSED */
1.302 djm 889: static int
1.261 markus 890: input_gssapi_response(int type, u_int32_t plen, struct ssh *ssh)
1.121 markus 891: {
1.260 markus 892: Authctxt *authctxt = ssh->authctxt;
1.121 markus 893: Gssctxt *gssctxt;
1.278 markus 894: size_t oidlen;
895: u_char *oidv = NULL;
896: int r;
1.121 markus 897:
898: if (authctxt == NULL)
899: fatal("input_gssapi_response: no authentication context");
900: gssctxt = authctxt->methoddata;
901:
902: /* Setup our OID */
1.278 markus 903: if ((r = sshpkt_get_string(ssh, &oidv, &oidlen)) != 0)
904: goto done;
1.121 markus 905:
1.129 markus 906: if (oidlen <= 2 ||
907: oidv[0] != SSH_GSS_OIDTYPE ||
908: oidv[1] != oidlen - 2) {
909: debug("Badly encoded mechanism OID received");
1.296 djm 910: userauth(ssh, NULL);
1.278 markus 911: goto ok;
1.121 markus 912: }
1.129 markus 913:
914: if (!ssh_gssapi_check_oid(gssctxt, oidv + 2, oidlen - 2))
915: fatal("Server returned different OID than expected");
1.121 markus 916:
1.278 markus 917: if ((r = sshpkt_get_end(ssh)) != 0)
918: goto done;
1.121 markus 919:
1.262 djm 920: if (GSS_ERROR(process_gssapi_token(ssh, GSS_C_NO_BUFFER))) {
1.121 markus 921: /* Start again with next method on list */
922: debug("Trying to start again");
1.296 djm 923: userauth(ssh, NULL);
1.278 markus 924: goto ok;
1.121 markus 925: }
1.278 markus 926: ok:
927: r = 0;
928: done:
929: free(oidv);
930: return r;
1.121 markus 931: }
932:
1.169 djm 933: /* ARGSUSED */
1.302 djm 934: static int
1.261 markus 935: input_gssapi_token(int type, u_int32_t plen, struct ssh *ssh)
1.121 markus 936: {
1.260 markus 937: Authctxt *authctxt = ssh->authctxt;
1.121 markus 938: gss_buffer_desc recv_tok;
1.278 markus 939: u_char *p = NULL;
940: size_t len;
1.130 markus 941: OM_uint32 status;
1.278 markus 942: int r;
1.121 markus 943:
944: if (authctxt == NULL)
945: fatal("input_gssapi_response: no authentication context");
946:
1.278 markus 947: if ((r = sshpkt_get_string(ssh, &p, &len)) != 0 ||
948: (r = sshpkt_get_end(ssh)) != 0)
949: goto out;
1.121 markus 950:
1.278 markus 951: recv_tok.value = p;
952: recv_tok.length = len;
1.262 djm 953: status = process_gssapi_token(ssh, &recv_tok);
1.121 markus 954:
1.278 markus 955: /* Start again with the next method in the list */
1.121 markus 956: if (GSS_ERROR(status)) {
1.296 djm 957: userauth(ssh, NULL);
1.278 markus 958: /* ok */
1.121 markus 959: }
1.278 markus 960: r = 0;
961: out:
962: free(p);
963: return r;
1.121 markus 964: }
965:
1.169 djm 966: /* ARGSUSED */
1.302 djm 967: static int
1.261 markus 968: input_gssapi_errtok(int type, u_int32_t plen, struct ssh *ssh)
1.121 markus 969: {
1.260 markus 970: Authctxt *authctxt = ssh->authctxt;
1.121 markus 971: Gssctxt *gssctxt;
972: gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
973: gss_buffer_desc recv_tok;
1.194 djm 974: OM_uint32 ms;
1.278 markus 975: u_char *p = NULL;
976: size_t len;
977: int r;
1.121 markus 978:
979: if (authctxt == NULL)
980: fatal("input_gssapi_response: no authentication context");
981: gssctxt = authctxt->methoddata;
982:
1.278 markus 983: if ((r = sshpkt_get_string(ssh, &p, &len)) != 0 ||
984: (r = sshpkt_get_end(ssh)) != 0) {
985: free(p);
986: return r;
987: }
1.121 markus 988:
989: /* Stick it into GSSAPI and see what it says */
1.278 markus 990: recv_tok.value = p;
991: recv_tok.length = len;
1.194 djm 992: (void)ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
1.140 djm 993: &recv_tok, &send_tok, NULL);
1.278 markus 994: free(p);
1.121 markus 995: gss_release_buffer(&ms, &send_tok);
996:
997: /* Server will be returning a failed packet after this one */
1.220 djm 998: return 0;
1.121 markus 999: }
1000:
1.169 djm 1001: /* ARGSUSED */
1.302 djm 1002: static int
1.261 markus 1003: input_gssapi_error(int type, u_int32_t plen, struct ssh *ssh)
1.121 markus 1004: {
1.278 markus 1005: char *msg = NULL;
1006: char *lang = NULL;
1007: int r;
1.121 markus 1008:
1.278 markus 1009: if ((r = sshpkt_get_u32(ssh, NULL)) != 0 || /* maj */
1010: (r = sshpkt_get_u32(ssh, NULL)) != 0 || /* min */
1011: (r = sshpkt_get_cstring(ssh, &msg, NULL)) != 0 ||
1012: (r = sshpkt_get_cstring(ssh, &lang, NULL)) != 0)
1013: goto out;
1014: r = sshpkt_get_end(ssh);
1.143 stevesk 1015: debug("Server GSSAPI Error:\n%s", msg);
1.278 markus 1016: out:
1.197 djm 1017: free(msg);
1018: free(lang);
1.278 markus 1019: return r;
1.121 markus 1020: }
1021: #endif /* GSSAPI */
1.20 markus 1022:
1.302 djm 1023: static int
1.295 djm 1024: userauth_none(struct ssh *ssh)
1.23 markus 1025: {
1.295 djm 1026: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.278 markus 1027: int r;
1028:
1.23 markus 1029: /* initial userauth request */
1.278 markus 1030: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1031: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1032: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1033: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1034: (r = sshpkt_send(ssh)) != 0)
1.331 djm 1035: fatal_fr(r, "send packet");
1.23 markus 1036: return 1;
1037: }
1038:
1.302 djm 1039: static int
1.295 djm 1040: userauth_passwd(struct ssh *ssh)
1.1 markus 1041: {
1.295 djm 1042: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.290 djm 1043: char *password, *prompt = NULL;
1.175 dtucker 1044: const char *host = options.host_key_alias ? options.host_key_alias :
1045: authctxt->host;
1.278 markus 1046: int r;
1.6 markus 1047:
1.292 djm 1048: if (authctxt->attempt_passwd++ >= options.number_of_password_prompts)
1.6 markus 1049: return 0;
1.13 todd 1050:
1.292 djm 1051: if (authctxt->attempt_passwd != 1)
1.13 todd 1052: error("Permission denied, please try again.");
1.1 markus 1053:
1.290 djm 1054: xasprintf(&prompt, "%s@%s's password: ", authctxt->server_user, host);
1.1 markus 1055: password = read_passphrase(prompt, 0);
1.278 markus 1056: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1057: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1058: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1059: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1060: (r = sshpkt_put_u8(ssh, 0)) != 0 ||
1061: (r = sshpkt_put_cstring(ssh, password)) != 0 ||
1062: (r = sshpkt_add_padding(ssh, 64)) != 0 ||
1063: (r = sshpkt_send(ssh)) != 0)
1.331 djm 1064: fatal_fr(r, "send packet");
1.99 markus 1065:
1.290 djm 1066: free(prompt);
1067: if (password != NULL)
1.278 markus 1068: freezero(password, strlen(password));
1069:
1070: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
1.99 markus 1071: &input_userauth_passwd_changereq);
1072:
1.1 markus 1073: return 1;
1074: }
1.169 djm 1075:
1.99 markus 1076: /*
1077: * parse PASSWD_CHANGEREQ, prompt user and send SSH2_MSG_USERAUTH_REQUEST
1078: */
1.169 djm 1079: /* ARGSUSED */
1.302 djm 1080: static int
1.261 markus 1081: input_userauth_passwd_changereq(int type, u_int32_t seqnr, struct ssh *ssh)
1.99 markus 1082: {
1.260 markus 1083: Authctxt *authctxt = ssh->authctxt;
1.278 markus 1084: char *info = NULL, *lang = NULL, *password = NULL, *retype = NULL;
1.266 dtucker 1085: char prompt[256];
1.252 djm 1086: const char *host;
1.278 markus 1087: int r;
1.99 markus 1088:
1089: debug2("input_userauth_passwd_changereq");
1090:
1091: if (authctxt == NULL)
1092: fatal("input_userauth_passwd_changereq: "
1093: "no authentication context");
1.252 djm 1094: host = options.host_key_alias ? options.host_key_alias : authctxt->host;
1.99 markus 1095:
1.278 markus 1096: if ((r = sshpkt_get_cstring(ssh, &info, NULL)) != 0 ||
1097: (r = sshpkt_get_cstring(ssh, &lang, NULL)) != 0)
1098: goto out;
1.99 markus 1099: if (strlen(info) > 0)
1.116 itojun 1100: logit("%s", info);
1.278 markus 1101: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1102: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1103: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1104: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1105: (r = sshpkt_put_u8(ssh, 1)) != 0) /* additional info */
1106: goto out;
1107:
1.104 deraadt 1108: snprintf(prompt, sizeof(prompt),
1.99 markus 1109: "Enter %.30s@%.128s's old password: ",
1.175 dtucker 1110: authctxt->server_user, host);
1.99 markus 1111: password = read_passphrase(prompt, 0);
1.278 markus 1112: if ((r = sshpkt_put_cstring(ssh, password)) != 0)
1113: goto out;
1114:
1115: freezero(password, strlen(password));
1.99 markus 1116: password = NULL;
1117: while (password == NULL) {
1.104 deraadt 1118: snprintf(prompt, sizeof(prompt),
1.99 markus 1119: "Enter %.30s@%.128s's new password: ",
1.175 dtucker 1120: authctxt->server_user, host);
1.99 markus 1121: password = read_passphrase(prompt, RP_ALLOW_EOF);
1122: if (password == NULL) {
1123: /* bail out */
1.278 markus 1124: r = 0;
1125: goto out;
1.99 markus 1126: }
1.104 deraadt 1127: snprintf(prompt, sizeof(prompt),
1.99 markus 1128: "Retype %.30s@%.128s's new password: ",
1.175 dtucker 1129: authctxt->server_user, host);
1.99 markus 1130: retype = read_passphrase(prompt, 0);
1131: if (strcmp(password, retype) != 0) {
1.278 markus 1132: freezero(password, strlen(password));
1.116 itojun 1133: logit("Mismatch; try again, EOF to quit.");
1.99 markus 1134: password = NULL;
1135: }
1.278 markus 1136: freezero(retype, strlen(retype));
1.99 markus 1137: }
1.278 markus 1138: if ((r = sshpkt_put_cstring(ssh, password)) != 0 ||
1139: (r = sshpkt_add_padding(ssh, 64)) != 0 ||
1140: (r = sshpkt_send(ssh)) != 0)
1141: goto out;
1.104 deraadt 1142:
1.278 markus 1143: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
1.99 markus 1144: &input_userauth_passwd_changereq);
1.278 markus 1145: r = 0;
1146: out:
1147: if (password)
1148: freezero(password, strlen(password));
1149: free(info);
1150: free(lang);
1151: return r;
1.117 markus 1152: }
1153:
1.272 djm 1154: /*
1155: * Select an algorithm for publickey signatures.
1156: * Returns algorithm (caller must free) or NULL if no mutual algorithm found.
1157: *
1158: * Call with ssh==NULL to ignore server-sig-algs extension list and
1159: * only attempt with the key's base signature type.
1160: */
1161: static char *
1162: key_sig_algorithm(struct ssh *ssh, const struct sshkey *key)
1.231 markus 1163: {
1.274 djm 1164: char *allowed, *oallowed, *cp, *tmp, *alg = NULL;
1.231 markus 1165:
1.272 djm 1166: /*
1167: * The signature algorithm will only differ from the key algorithm
1168: * for RSA keys/certs and when the server advertises support for
1169: * newer (SHA2) algorithms.
1170: */
1171: if (ssh == NULL || ssh->kex->server_sig_algs == NULL ||
1.288 djm 1172: (key->type != KEY_RSA && key->type != KEY_RSA_CERT) ||
1173: (key->type == KEY_RSA_CERT && (datafellows & SSH_BUG_SIGTYPE))) {
1.272 djm 1174: /* Filter base key signature alg against our configuration */
1.279 markus 1175: return match_list(sshkey_ssh_name(key),
1.272 djm 1176: options.pubkey_key_types, NULL);
1.231 markus 1177: }
1178:
1.272 djm 1179: /*
1180: * For RSA keys/certs, since these might have a different sig type:
1181: * find the first entry in PubkeyAcceptedKeyTypes of the right type
1182: * that also appears in the supported signature algorithms list from
1183: * the server.
1184: */
1185: oallowed = allowed = xstrdup(options.pubkey_key_types);
1186: while ((cp = strsep(&allowed, ",")) != NULL) {
1187: if (sshkey_type_from_name(cp) != key->type)
1188: continue;
1.323 djm 1189: tmp = match_list(sshkey_sigalg_by_name(cp),
1190: ssh->kex->server_sig_algs, NULL);
1.274 djm 1191: if (tmp != NULL)
1192: alg = xstrdup(cp);
1193: free(tmp);
1.272 djm 1194: if (alg != NULL)
1195: break;
1.269 djm 1196: }
1.272 djm 1197: free(oallowed);
1198: return alg;
1.269 djm 1199: }
1200:
1.117 markus 1201: static int
1.214 djm 1202: identity_sign(struct identity *id, u_char **sigp, size_t *lenp,
1.272 djm 1203: const u_char *data, size_t datalen, u_int compat, const char *alg)
1.117 markus 1204: {
1.309 djm 1205: struct sshkey *sign_key = NULL, *prv = NULL;
1206: int r = SSH_ERR_INTERNAL_ERROR;
1.312 djm 1207: struct notifier_ctx *notifier = NULL;
1.325 djm 1208: char *fp = NULL, *pin = NULL, *prompt = NULL;
1.309 djm 1209:
1210: *sigp = NULL;
1211: *lenp = 0;
1.99 markus 1212:
1.272 djm 1213: /* The agent supports this key. */
1.269 djm 1214: if (id->key != NULL && id->agent_fd != -1) {
1.272 djm 1215: return ssh_agent_sign(id->agent_fd, id->key, sigp, lenp,
1216: data, datalen, alg, compat);
1.269 djm 1217: }
1.214 djm 1218:
1.117 markus 1219: /*
1.272 djm 1220: * We have already loaded the private key or the private key is
1221: * stored in external hardware.
1.117 markus 1222: */
1.255 djm 1223: if (id->key != NULL &&
1.272 djm 1224: (id->isprivate || (id->key->flags & SSHKEY_FLAG_EXT))) {
1.309 djm 1225: sign_key = id->key;
1226: } else {
1227: /* Load the private key from the file. */
1228: if ((prv = load_identity_file(id)) == NULL)
1229: return SSH_ERR_KEY_NOT_FOUND;
1230: if (id->key != NULL && !sshkey_equal_public(prv, id->key)) {
1.331 djm 1231: error_f("private key %s contents do not match public",
1232: id->filename);
1.309 djm 1233: r = SSH_ERR_KEY_NOT_FOUND;
1234: goto out;
1235: }
1236: sign_key = prv;
1.325 djm 1237: if (sshkey_is_sk(sign_key)) {
1238: if ((sign_key->sk_flags &
1239: SSH_SK_USER_VERIFICATION_REQD)) {
1240: xasprintf(&prompt, "Enter PIN for %s key %s: ",
1241: sshkey_type(sign_key), id->filename);
1242: pin = read_passphrase(prompt, 0);
1243: }
1244: if ((sign_key->sk_flags & SSH_SK_USER_PRESENCE_REQD)) {
1245: /* XXX should batch mode just skip these? */
1246: if ((fp = sshkey_fingerprint(sign_key,
1247: options.fingerprint_hash,
1248: SSH_FP_DEFAULT)) == NULL)
1.331 djm 1249: fatal_f("fingerprint failed");
1.325 djm 1250: notifier = notify_start(options.batch_mode,
1251: "Confirm user presence for key %s %s",
1252: sshkey_type(sign_key), fp);
1253: free(fp);
1254: }
1.312 djm 1255: }
1.272 djm 1256: }
1.310 djm 1257: if ((r = sshkey_sign(sign_key, sigp, lenp, data, datalen,
1.325 djm 1258: alg, options.sk_provider, pin, compat)) != 0) {
1.331 djm 1259: debug_fr(r, "sshkey_sign");
1.309 djm 1260: goto out;
1261: }
1262: /*
1263: * PKCS#11 tokens may not support all signature algorithms,
1264: * so check what we get back.
1265: */
1266: if ((r = sshkey_check_sigtype(*sigp, *lenp, alg)) != 0) {
1.331 djm 1267: debug_fr(r, "sshkey_check_sigtype");
1.309 djm 1268: goto out;
1.265 djm 1269: }
1.309 djm 1270: /* success */
1271: r = 0;
1272: out:
1.325 djm 1273: free(prompt);
1274: if (pin != NULL)
1275: freezero(pin, strlen(pin));
1.334 djm 1276: notify_complete(notifier, "User presence confirmed");
1.214 djm 1277: sshkey_free(prv);
1.269 djm 1278: return r;
1.51 markus 1279: }
1280:
1.76 itojun 1281: static int
1.255 djm 1282: id_filename_matches(Identity *id, Identity *private_id)
1283: {
1284: const char *suffixes[] = { ".pub", "-cert.pub", NULL };
1285: size_t len = strlen(id->filename), plen = strlen(private_id->filename);
1286: size_t i, slen;
1287:
1288: if (strcmp(id->filename, private_id->filename) == 0)
1289: return 1;
1290: for (i = 0; suffixes[i]; i++) {
1291: slen = strlen(suffixes[i]);
1292: if (len > slen && plen == len - slen &&
1293: strcmp(id->filename + (len - slen), suffixes[i]) == 0 &&
1294: memcmp(id->filename, private_id->filename, plen) == 0)
1295: return 1;
1296: }
1297: return 0;
1298: }
1299:
1300: static int
1.295 djm 1301: sign_and_send_pubkey(struct ssh *ssh, Identity *id)
1.1 markus 1302: {
1.295 djm 1303: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.272 djm 1304: struct sshbuf *b = NULL;
1305: Identity *private_id, *sign_id = NULL;
1306: u_char *signature = NULL;
1307: size_t slen = 0, skip = 0;
1308: int r, fallback_sigtype, sent = 0;
1309: char *alg = NULL, *fp = NULL;
1310: const char *loc = "";
1.1 markus 1311:
1.222 djm 1312: if ((fp = sshkey_fingerprint(id->key, options.fingerprint_hash,
1313: SSH_FP_DEFAULT)) == NULL)
1314: return 0;
1.51 markus 1315:
1.331 djm 1316: debug3_f("%s %s", sshkey_type(id->key), fp);
1.1 markus 1317:
1.227 djm 1318: /*
1319: * If the key is an certificate, try to find a matching private key
1320: * and use it to complete the signature.
1.241 djm 1321: * If no such private key exists, fall back to trying the certificate
1322: * key itself in case it has a private half already loaded.
1.272 djm 1323: * This will try to set sign_id to the private key that will perform
1324: * the signature.
1.227 djm 1325: */
1.272 djm 1326: if (sshkey_is_cert(id->key)) {
1.227 djm 1327: TAILQ_FOREACH(private_id, &authctxt->keys, next) {
1328: if (sshkey_equal_public(id->key, private_id->key) &&
1329: id->key->type != private_id->key->type) {
1.272 djm 1330: sign_id = private_id;
1.227 djm 1331: break;
1332: }
1333: }
1.255 djm 1334: /*
1335: * Exact key matches are preferred, but also allow
1336: * filename matches for non-PKCS#11/agent keys that
1337: * didn't load public keys. This supports the case
1338: * of keeping just a private key file and public
1339: * certificate on disk.
1340: */
1.272 djm 1341: if (sign_id == NULL &&
1342: !id->isprivate && id->agent_fd == -1 &&
1.255 djm 1343: (id->key->flags & SSHKEY_FLAG_EXT) == 0) {
1344: TAILQ_FOREACH(private_id, &authctxt->keys, next) {
1345: if (private_id->key == NULL &&
1346: id_filename_matches(id, private_id)) {
1.272 djm 1347: sign_id = private_id;
1.255 djm 1348: break;
1349: }
1350: }
1351: }
1.272 djm 1352: if (sign_id != NULL) {
1.331 djm 1353: debug2_f("using private key \"%s\"%s for "
1354: "certificate", id->filename,
1.227 djm 1355: id->agent_fd != -1 ? " from agent" : "");
1356: } else {
1.331 djm 1357: debug_f("no separate private key for certificate "
1358: "\"%s\"", id->filename);
1.227 djm 1359: }
1360: }
1361:
1.272 djm 1362: /*
1363: * If the above didn't select another identity to do the signing
1364: * then default to the one we started with.
1365: */
1366: if (sign_id == NULL)
1367: sign_id = id;
1368:
1369: /* assemble and sign data */
1370: for (fallback_sigtype = 0; fallback_sigtype <= 1; fallback_sigtype++) {
1371: free(alg);
1372: slen = 0;
1373: signature = NULL;
1374: if ((alg = key_sig_algorithm(fallback_sigtype ? NULL : ssh,
1375: id->key)) == NULL) {
1.331 djm 1376: error_f("no mutual signature supported");
1.272 djm 1377: goto out;
1378: }
1.331 djm 1379: debug3_f("signing using %s %s", alg, fp);
1.272 djm 1380:
1381: sshbuf_free(b);
1382: if ((b = sshbuf_new()) == NULL)
1.331 djm 1383: fatal_f("sshbuf_new failed");
1.272 djm 1384: if (datafellows & SSH_OLD_SESSIONID) {
1385: if ((r = sshbuf_put(b, session_id2,
1.331 djm 1386: session_id2_len)) != 0)
1387: fatal_fr(r, "sshbuf_put");
1.272 djm 1388: } else {
1389: if ((r = sshbuf_put_string(b, session_id2,
1.331 djm 1390: session_id2_len)) != 0)
1391: fatal_fr(r, "sshbuf_put_string");
1.272 djm 1392: }
1.278 markus 1393: skip = sshbuf_len(b);
1.272 djm 1394: if ((r = sshbuf_put_u8(b, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1395: (r = sshbuf_put_cstring(b, authctxt->server_user)) != 0 ||
1396: (r = sshbuf_put_cstring(b, authctxt->service)) != 0 ||
1397: (r = sshbuf_put_cstring(b, authctxt->method->name)) != 0 ||
1398: (r = sshbuf_put_u8(b, 1)) != 0 ||
1399: (r = sshbuf_put_cstring(b, alg)) != 0 ||
1400: (r = sshkey_puts(id->key, b)) != 0) {
1.331 djm 1401: fatal_fr(r, "assemble signed data");
1.272 djm 1402: }
1403:
1404: /* generate signature */
1405: r = identity_sign(sign_id, &signature, &slen,
1406: sshbuf_ptr(b), sshbuf_len(b), datafellows, alg);
1407: if (r == 0)
1408: break;
1409: else if (r == SSH_ERR_KEY_NOT_FOUND)
1410: goto out; /* soft failure */
1411: else if (r == SSH_ERR_SIGN_ALG_UNSUPPORTED &&
1412: !fallback_sigtype) {
1413: if (sign_id->agent_fd != -1)
1414: loc = "agent ";
1415: else if ((sign_id->key->flags & SSHKEY_FLAG_EXT) != 0)
1416: loc = "token ";
1417: logit("%skey %s %s returned incorrect signature type",
1418: loc, sshkey_type(id->key), fp);
1419: continue;
1420: }
1.331 djm 1421: error_fr(r, "signing failed for %s \"%s\"%s",
1.315 djm 1422: sshkey_type(sign_id->key), sign_id->filename,
1.331 djm 1423: id->agent_fd != -1 ? " from agent" : "");
1.272 djm 1424: goto out;
1.17 markus 1425: }
1.272 djm 1426: if (slen == 0 || signature == NULL) /* shouldn't happen */
1.331 djm 1427: fatal_f("no signature");
1.51 markus 1428:
1.1 markus 1429: /* append signature */
1.272 djm 1430: if ((r = sshbuf_put_string(b, signature, slen)) != 0)
1.331 djm 1431: fatal_fr(r, "append signature");
1.1 markus 1432:
1.272 djm 1433: #ifdef DEBUG_PK
1434: sshbuf_dump(b, stderr);
1435: #endif
1.1 markus 1436: /* skip session id and packet type */
1.272 djm 1437: if ((r = sshbuf_consume(b, skip + 1)) != 0)
1.331 djm 1438: fatal_fr(r, "consume");
1.1 markus 1439:
1440: /* put remaining data from buffer into packet */
1.272 djm 1441: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1442: (r = sshpkt_putb(ssh, b)) != 0 ||
1443: (r = sshpkt_send(ssh)) != 0)
1.331 djm 1444: fatal_fr(r, "enqueue request");
1.272 djm 1445:
1446: /* success */
1447: sent = 1;
1.17 markus 1448:
1.272 djm 1449: out:
1450: free(fp);
1451: free(alg);
1452: sshbuf_free(b);
1453: freezero(signature, slen);
1454: return sent;
1.16 markus 1455: }
1456:
1.76 itojun 1457: static int
1.295 djm 1458: send_pubkey_test(struct ssh *ssh, Identity *id)
1.20 markus 1459: {
1.295 djm 1460: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.272 djm 1461: u_char *blob = NULL;
1462: char *alg = NULL;
1.278 markus 1463: size_t bloblen;
1464: u_int have_sig = 0;
1465: int sent = 0, r;
1.20 markus 1466:
1.272 djm 1467: if ((alg = key_sig_algorithm(ssh, id->key)) == NULL) {
1.331 djm 1468: debug_f("no mutual signature algorithm");
1.272 djm 1469: goto out;
1470: }
1.16 markus 1471:
1.278 markus 1472: if ((r = sshkey_to_blob(id->key, &blob, &bloblen)) != 0) {
1.51 markus 1473: /* we cannot handle this key */
1.331 djm 1474: debug3_f("cannot handle key");
1.272 djm 1475: goto out;
1.16 markus 1476: }
1.51 markus 1477: /* register callback for USERAUTH_PK_OK message */
1.278 markus 1478: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_PK_OK, &input_userauth_pk_ok);
1.51 markus 1479:
1.278 markus 1480: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1481: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1482: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1483: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1484: (r = sshpkt_put_u8(ssh, have_sig)) != 0 ||
1485: (r = sshpkt_put_cstring(ssh, alg)) != 0 ||
1486: (r = sshpkt_put_string(ssh, blob, bloblen)) != 0 ||
1487: (r = sshpkt_send(ssh)) != 0)
1.331 djm 1488: fatal_fr(r, "send packet");
1.272 djm 1489: sent = 1;
1.278 markus 1490:
1491: out:
1.272 djm 1492: free(alg);
1.197 djm 1493: free(blob);
1.272 djm 1494: return sent;
1.51 markus 1495: }
1496:
1.259 markus 1497: static struct sshkey *
1.229 jcs 1498: load_identity_file(Identity *id)
1.51 markus 1499: {
1.259 markus 1500: struct sshkey *private = NULL;
1.229 jcs 1501: char prompt[300], *passphrase, *comment;
1.308 dtucker 1502: int r, quit = 0, i;
1.52 markus 1503: struct stat st;
1.16 markus 1504:
1.306 deraadt 1505: if (stat(id->filename, &st) == -1) {
1.330 djm 1506: do_log2(id->userprovided ?
1507: SYSLOG_LEVEL_INFO : SYSLOG_LEVEL_DEBUG3,
1508: "no such identity: %s: %s", id->filename, strerror(errno));
1.52 markus 1509: return NULL;
1510: }
1.214 djm 1511: snprintf(prompt, sizeof prompt,
1.229 jcs 1512: "Enter passphrase for key '%.100s': ", id->filename);
1.214 djm 1513: for (i = 0; i <= options.number_of_password_prompts; i++) {
1514: if (i == 0)
1515: passphrase = "";
1516: else {
1.20 markus 1517: passphrase = read_passphrase(prompt, 0);
1.214 djm 1518: if (*passphrase == '\0') {
1.20 markus 1519: debug2("no passphrase given, try next key");
1.214 djm 1520: free(passphrase);
1521: break;
1522: }
1523: }
1.229 jcs 1524: switch ((r = sshkey_load_private_type(KEY_UNSPEC, id->filename,
1.308 dtucker 1525: passphrase, &private, &comment))) {
1.214 djm 1526: case 0:
1527: break;
1528: case SSH_ERR_KEY_WRONG_PASSPHRASE:
1529: if (options.batch_mode) {
1530: quit = 1;
1531: break;
1532: }
1.215 djm 1533: if (i != 0)
1534: debug2("bad passphrase given, try again...");
1.214 djm 1535: break;
1536: case SSH_ERR_SYSTEM_ERROR:
1537: if (errno == ENOENT) {
1.331 djm 1538: debug2_r(r, "Load key \"%s\"", id->filename);
1.51 markus 1539: quit = 1;
1.214 djm 1540: break;
1.20 markus 1541: }
1.214 djm 1542: /* FALLTHROUGH */
1543: default:
1.331 djm 1544: error_r(r, "Load key \"%s\"", id->filename);
1.214 djm 1545: quit = 1;
1546: break;
1547: }
1.311 markus 1548: if (private != NULL && sshkey_is_sk(private) &&
1.309 djm 1549: options.sk_provider == NULL) {
1.319 naddy 1550: debug("key \"%s\" is an authenticator-hosted key, "
1551: "but no provider specified", id->filename);
1.309 djm 1552: sshkey_free(private);
1553: private = NULL;
1554: quit = 1;
1555: }
1.230 djm 1556: if (!quit && private != NULL && id->agent_fd == -1 &&
1.229 jcs 1557: !(id->key && id->isprivate))
1558: maybe_add_key_to_agent(id->filename, private, comment,
1559: passphrase);
1.278 markus 1560: if (i > 0)
1561: freezero(passphrase, strlen(passphrase));
1.232 mmcc 1562: free(comment);
1.214 djm 1563: if (private != NULL || quit)
1564: break;
1.16 markus 1565: }
1.51 markus 1566: return private;
1567: }
1568:
1.272 djm 1569: static int
1570: key_type_allowed_by_config(struct sshkey *key)
1571: {
1572: if (match_pattern_list(sshkey_ssh_name(key),
1573: options.pubkey_key_types, 0) == 1)
1574: return 1;
1575:
1576: /* RSA keys/certs might be allowed by alternate signature types */
1577: switch (key->type) {
1578: case KEY_RSA:
1579: if (match_pattern_list("rsa-sha2-512",
1580: options.pubkey_key_types, 0) == 1)
1581: return 1;
1582: if (match_pattern_list("rsa-sha2-256",
1583: options.pubkey_key_types, 0) == 1)
1584: return 1;
1585: break;
1586: case KEY_RSA_CERT:
1587: if (match_pattern_list("rsa-sha2-512-cert-v01@openssh.com",
1588: options.pubkey_key_types, 0) == 1)
1589: return 1;
1590: if (match_pattern_list("rsa-sha2-256-cert-v01@openssh.com",
1591: options.pubkey_key_types, 0) == 1)
1592: return 1;
1593: break;
1594: }
1595: return 0;
1596: }
1597:
1598:
1.117 markus 1599: /*
1600: * try keys in the following order:
1.332 djm 1601: * 1. certificates listed in the config file
1602: * 2. other input certificates
1.227 djm 1603: * 3. agent keys that are found in the config file
1604: * 4. other agent keys
1605: * 5. keys that are only listed in the config file
1.117 markus 1606: */
1607: static void
1608: pubkey_prepare(Authctxt *authctxt)
1.51 markus 1609: {
1.214 djm 1610: struct identity *id, *id2, *tmp;
1611: struct idlist agent, files, *preferred;
1612: struct sshkey *key;
1.230 djm 1613: int agent_fd = -1, i, r, found;
1.214 djm 1614: size_t j;
1615: struct ssh_identitylist *idlist;
1.287 djm 1616: char *ident;
1.51 markus 1617:
1.117 markus 1618: TAILQ_INIT(&agent); /* keys from the agent */
1619: TAILQ_INIT(&files); /* keys from the config file */
1620: preferred = &authctxt->keys;
1621: TAILQ_INIT(preferred); /* preferred order of keys */
1622:
1.190 djm 1623: /* list of keys stored in the filesystem and PKCS#11 */
1.117 markus 1624: for (i = 0; i < options.num_identity_files; i++) {
1625: key = options.identity_keys[i];
1.309 djm 1626: if (key && key->cert &&
1627: key->cert->type != SSH2_CERT_TYPE_USER) {
1.331 djm 1628: debug_f("ignoring certificate %s: not a user "
1629: "certificate", options.identity_files[i]);
1.309 djm 1630: continue;
1631: }
1.311 markus 1632: if (key && sshkey_is_sk(key) && options.sk_provider == NULL) {
1.331 djm 1633: debug_f("ignoring authenticator-hosted key %s as no "
1.309 djm 1634: "SecurityKeyProvider has been specified",
1.331 djm 1635: options.identity_files[i]);
1.117 markus 1636: continue;
1.309 djm 1637: }
1.117 markus 1638: options.identity_keys[i] = NULL;
1.150 djm 1639: id = xcalloc(1, sizeof(*id));
1.230 djm 1640: id->agent_fd = -1;
1.117 markus 1641: id->key = key;
1642: id->filename = xstrdup(options.identity_files[i]);
1.192 dtucker 1643: id->userprovided = options.identity_file_userprovided[i];
1.117 markus 1644: TAILQ_INSERT_TAIL(&files, id, next);
1.190 djm 1645: }
1.227 djm 1646: /* list of certificates specified by user */
1647: for (i = 0; i < options.num_certificate_files; i++) {
1648: key = options.certificates[i];
1.278 markus 1649: if (!sshkey_is_cert(key) || key->cert == NULL ||
1.309 djm 1650: key->cert->type != SSH2_CERT_TYPE_USER) {
1.331 djm 1651: debug_f("ignoring certificate %s: not a user "
1652: "certificate", options.identity_files[i]);
1.227 djm 1653: continue;
1.309 djm 1654: }
1.311 markus 1655: if (key && sshkey_is_sk(key) && options.sk_provider == NULL) {
1.331 djm 1656: debug_f("ignoring authenticator-hosted key "
1.319 naddy 1657: "certificate %s as no "
1.309 djm 1658: "SecurityKeyProvider has been specified",
1.331 djm 1659: options.identity_files[i]);
1.309 djm 1660: continue;
1661: }
1.227 djm 1662: id = xcalloc(1, sizeof(*id));
1.230 djm 1663: id->agent_fd = -1;
1.227 djm 1664: id->key = key;
1665: id->filename = xstrdup(options.certificate_files[i]);
1666: id->userprovided = options.certificate_file_userprovided[i];
1667: TAILQ_INSERT_TAIL(preferred, id, next);
1.117 markus 1668: }
1669: /* list of keys supported by the agent */
1.214 djm 1670: if ((r = ssh_get_authentication_socket(&agent_fd)) != 0) {
1671: if (r != SSH_ERR_AGENT_NOT_PRESENT)
1.331 djm 1672: debug_fr(r, "ssh_get_authentication_socket");
1.258 naddy 1673: } else if ((r = ssh_fetch_identitylist(agent_fd, &idlist)) != 0) {
1.214 djm 1674: if (r != SSH_ERR_AGENT_NO_IDENTITIES)
1.331 djm 1675: debug_fr(r, "ssh_fetch_identitylist");
1.237 markus 1676: close(agent_fd);
1.214 djm 1677: } else {
1678: for (j = 0; j < idlist->nkeys; j++) {
1.117 markus 1679: found = 0;
1680: TAILQ_FOREACH(id, &files, next) {
1.214 djm 1681: /*
1682: * agent keys from the config file are
1683: * preferred
1684: */
1685: if (sshkey_equal(idlist->keys[j], id->key)) {
1.117 markus 1686: TAILQ_REMOVE(&files, id, next);
1687: TAILQ_INSERT_TAIL(preferred, id, next);
1.214 djm 1688: id->agent_fd = agent_fd;
1.117 markus 1689: found = 1;
1690: break;
1691: }
1692: }
1.135 markus 1693: if (!found && !options.identities_only) {
1.150 djm 1694: id = xcalloc(1, sizeof(*id));
1.214 djm 1695: /* XXX "steals" key/comment from idlist */
1696: id->key = idlist->keys[j];
1697: id->filename = idlist->comments[j];
1698: idlist->keys[j] = NULL;
1699: idlist->comments[j] = NULL;
1700: id->agent_fd = agent_fd;
1.117 markus 1701: TAILQ_INSERT_TAIL(&agent, id, next);
1702: }
1703: }
1.214 djm 1704: ssh_free_identitylist(idlist);
1.117 markus 1705: /* append remaining agent keys */
1.324 bket 1706: TAILQ_CONCAT(preferred, &agent, next);
1.214 djm 1707: authctxt->agent_fd = agent_fd;
1.244 djm 1708: }
1709: /* Prefer PKCS11 keys that are explicitly listed */
1710: TAILQ_FOREACH_SAFE(id, &files, next, tmp) {
1711: if (id->key == NULL || (id->key->flags & SSHKEY_FLAG_EXT) == 0)
1712: continue;
1713: found = 0;
1714: TAILQ_FOREACH(id2, &files, next) {
1715: if (id2->key == NULL ||
1.321 djm 1716: (id2->key->flags & SSHKEY_FLAG_EXT) != 0)
1.244 djm 1717: continue;
1718: if (sshkey_equal(id->key, id2->key)) {
1719: TAILQ_REMOVE(&files, id, next);
1720: TAILQ_INSERT_TAIL(preferred, id, next);
1721: found = 1;
1722: break;
1723: }
1724: }
1725: /* If IdentitiesOnly set and key not found then don't use it */
1726: if (!found && options.identities_only) {
1727: TAILQ_REMOVE(&files, id, next);
1.278 markus 1728: freezero(id, sizeof(*id));
1.244 djm 1729: }
1.117 markus 1730: }
1731: /* append remaining keys from the config file */
1.324 bket 1732: TAILQ_CONCAT(preferred, &files, next);
1.228 djm 1733: /* finally, filter by PubkeyAcceptedKeyTypes */
1734: TAILQ_FOREACH_SAFE(id, preferred, next, id2) {
1.273 djm 1735: if (id->key != NULL && !key_type_allowed_by_config(id->key)) {
1.228 djm 1736: debug("Skipping %s key %s - "
1737: "not in PubkeyAcceptedKeyTypes",
1738: sshkey_ssh_name(id->key), id->filename);
1739: TAILQ_REMOVE(preferred, id, next);
1740: sshkey_free(id->key);
1741: free(id->filename);
1742: memset(id, 0, sizeof(*id));
1743: continue;
1744: }
1.117 markus 1745: }
1.287 djm 1746: /* List the keys we plan on using */
1747: TAILQ_FOREACH_SAFE(id, preferred, next, id2) {
1748: ident = format_identity(id);
1749: debug("Will attempt key: %s", ident);
1750: free(ident);
1751: }
1.331 djm 1752: debug2_f("done");
1.17 markus 1753: }
1754:
1.117 markus 1755: static void
1.303 djm 1756: pubkey_cleanup(struct ssh *ssh)
1.51 markus 1757: {
1.302 djm 1758: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.117 markus 1759: Identity *id;
1.51 markus 1760:
1.289 djm 1761: if (authctxt->agent_fd != -1) {
1.214 djm 1762: ssh_close_authentication_socket(authctxt->agent_fd);
1.289 djm 1763: authctxt->agent_fd = -1;
1764: }
1.117 markus 1765: for (id = TAILQ_FIRST(&authctxt->keys); id;
1766: id = TAILQ_FIRST(&authctxt->keys)) {
1767: TAILQ_REMOVE(&authctxt->keys, id, next);
1.235 mmcc 1768: sshkey_free(id->key);
1.197 djm 1769: free(id->filename);
1770: free(id);
1.117 markus 1771: }
1.1 markus 1772: }
1773:
1.251 djm 1774: static void
1775: pubkey_reset(Authctxt *authctxt)
1776: {
1777: Identity *id;
1778:
1779: TAILQ_FOREACH(id, &authctxt->keys, next)
1780: id->tried = 0;
1781: }
1782:
1.225 markus 1783: static int
1784: try_identity(Identity *id)
1785: {
1786: if (!id->key)
1787: return (0);
1.279 markus 1788: if (sshkey_type_plain(id->key->type) == KEY_RSA &&
1.225 markus 1789: (datafellows & SSH_BUG_RSASIGMD5) != 0) {
1790: debug("Skipped %s key %s for RSA/MD5 server",
1.279 markus 1791: sshkey_type(id->key), id->filename);
1.225 markus 1792: return (0);
1793: }
1.257 djm 1794: return 1;
1.225 markus 1795: }
1796:
1.302 djm 1797: static int
1.295 djm 1798: userauth_pubkey(struct ssh *ssh)
1.20 markus 1799: {
1.295 djm 1800: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.117 markus 1801: Identity *id;
1.20 markus 1802: int sent = 0;
1.287 djm 1803: char *ident;
1.20 markus 1804:
1.117 markus 1805: while ((id = TAILQ_FIRST(&authctxt->keys))) {
1806: if (id->tried++)
1807: return (0);
1.127 markus 1808: /* move key to the end of the queue */
1.117 markus 1809: TAILQ_REMOVE(&authctxt->keys, id, next);
1810: TAILQ_INSERT_TAIL(&authctxt->keys, id, next);
1811: /*
1812: * send a test message if we have the public key. for
1813: * encrypted keys we cannot do this and have to load the
1814: * private key instead
1815: */
1.200 djm 1816: if (id->key != NULL) {
1.225 markus 1817: if (try_identity(id)) {
1.287 djm 1818: ident = format_identity(id);
1819: debug("Offering public key: %s", ident);
1820: free(ident);
1.295 djm 1821: sent = send_pubkey_test(ssh, id);
1.200 djm 1822: }
1823: } else {
1.117 markus 1824: debug("Trying private key: %s", id->filename);
1.229 jcs 1825: id->key = load_identity_file(id);
1.117 markus 1826: if (id->key != NULL) {
1.225 markus 1827: if (try_identity(id)) {
1828: id->isprivate = 1;
1.295 djm 1829: sent = sign_and_send_pubkey(ssh, id);
1.200 djm 1830: }
1.278 markus 1831: sshkey_free(id->key);
1.117 markus 1832: id->key = NULL;
1.251 djm 1833: id->isprivate = 0;
1.51 markus 1834: }
1835: }
1.117 markus 1836: if (sent)
1837: return (sent);
1.28 markus 1838: }
1.117 markus 1839: return (0);
1.20 markus 1840: }
1841:
1.23 markus 1842: /*
1843: * Send userauth request message specifying keyboard-interactive method.
1844: */
1.302 djm 1845: static int
1.295 djm 1846: userauth_kbdint(struct ssh *ssh)
1.23 markus 1847: {
1.295 djm 1848: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.278 markus 1849: int r;
1.23 markus 1850:
1.292 djm 1851: if (authctxt->attempt_kbdint++ >= options.number_of_password_prompts)
1.23 markus 1852: return 0;
1.82 markus 1853: /* disable if no SSH2_MSG_USERAUTH_INFO_REQUEST has been seen */
1.292 djm 1854: if (authctxt->attempt_kbdint > 1 && !authctxt->info_req_seen) {
1.82 markus 1855: debug3("userauth_kbdint: disable: no info_req_seen");
1.278 markus 1856: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_INFO_REQUEST, NULL);
1.82 markus 1857: return 0;
1858: }
1.23 markus 1859:
1860: debug2("userauth_kbdint");
1.278 markus 1861: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1862: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1863: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1864: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1865: (r = sshpkt_put_cstring(ssh, "")) != 0 || /* lang */
1866: (r = sshpkt_put_cstring(ssh, options.kbd_interactive_devices ?
1867: options.kbd_interactive_devices : "")) != 0 ||
1868: (r = sshpkt_send(ssh)) != 0)
1.331 djm 1869: fatal_fr(r, "send packet");
1.23 markus 1870:
1.278 markus 1871: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_INFO_REQUEST, &input_userauth_info_req);
1.23 markus 1872: return 1;
1873: }
1874:
1875: /*
1.46 markus 1876: * parse INFO_REQUEST, prompt user and send INFO_RESPONSE
1.23 markus 1877: */
1.302 djm 1878: static int
1.261 markus 1879: input_userauth_info_req(int type, u_int32_t seq, struct ssh *ssh)
1.23 markus 1880: {
1.260 markus 1881: Authctxt *authctxt = ssh->authctxt;
1.278 markus 1882: char *name = NULL, *inst = NULL, *lang = NULL, *prompt = NULL;
1.335 djm 1883: char *display_prompt = NULL, *response = NULL;
1.278 markus 1884: u_char echo = 0;
1.32 markus 1885: u_int num_prompts, i;
1.278 markus 1886: int r;
1.23 markus 1887:
1.335 djm 1888: debug2_f("entering");
1.23 markus 1889:
1890: if (authctxt == NULL)
1.335 djm 1891: fatal_f("no authentication context");
1.82 markus 1892:
1893: authctxt->info_req_seen = 1;
1.23 markus 1894:
1.278 markus 1895: if ((r = sshpkt_get_cstring(ssh, &name, NULL)) != 0 ||
1896: (r = sshpkt_get_cstring(ssh, &inst, NULL)) != 0 ||
1897: (r = sshpkt_get_cstring(ssh, &lang, NULL)) != 0)
1898: goto out;
1.23 markus 1899: if (strlen(name) > 0)
1.116 itojun 1900: logit("%s", name);
1.23 markus 1901: if (strlen(inst) > 0)
1.116 itojun 1902: logit("%s", inst);
1.23 markus 1903:
1.278 markus 1904: if ((r = sshpkt_get_u32(ssh, &num_prompts)) != 0)
1905: goto out;
1.23 markus 1906: /*
1907: * Begin to build info response packet based on prompts requested.
1908: * We commit to providing the correct number of responses, so if
1909: * further on we run into a problem that prevents this, we have to
1910: * be sure and clean this up and send a correct error response.
1911: */
1.278 markus 1912: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_INFO_RESPONSE)) != 0 ||
1913: (r = sshpkt_put_u32(ssh, num_prompts)) != 0)
1914: goto out;
1.23 markus 1915:
1.335 djm 1916: debug2_f("num_prompts %d", num_prompts);
1.23 markus 1917: for (i = 0; i < num_prompts; i++) {
1.278 markus 1918: if ((r = sshpkt_get_cstring(ssh, &prompt, NULL)) != 0 ||
1919: (r = sshpkt_get_u8(ssh, &echo)) != 0)
1920: goto out;
1.336 ! djm 1921: if (asmprintf(&display_prompt, INT_MAX, NULL, "(%s@%s) %s",
1.335 djm 1922: authctxt->server_user, options.host_key_alias ?
1.336 ! djm 1923: options.host_key_alias : authctxt->host, prompt) == -1)
! 1924: fatal_f("asmprintf failed");
1.335 djm 1925: response = read_passphrase(display_prompt, echo ? RP_ECHO : 0);
1.278 markus 1926: if ((r = sshpkt_put_cstring(ssh, response)) != 0)
1927: goto out;
1928: freezero(response, strlen(response));
1.197 djm 1929: free(prompt);
1.335 djm 1930: free(display_prompt);
1931: display_prompt = response = prompt = NULL;
1.23 markus 1932: }
1.278 markus 1933: /* done with parsing incoming message. */
1934: if ((r = sshpkt_get_end(ssh)) != 0 ||
1935: (r = sshpkt_add_padding(ssh, 64)) != 0)
1936: goto out;
1937: r = sshpkt_send(ssh);
1938: out:
1939: if (response)
1940: freezero(response, strlen(response));
1941: free(prompt);
1.335 djm 1942: free(display_prompt);
1.278 markus 1943: free(name);
1944: free(inst);
1945: free(lang);
1946: return r;
1.68 markus 1947: }
1948:
1.100 markus 1949: static int
1.294 djm 1950: ssh_keysign(struct ssh *ssh, struct sshkey *key, u_char **sigp, size_t *lenp,
1.223 djm 1951: const u_char *data, size_t datalen)
1.100 markus 1952: {
1.223 djm 1953: struct sshbuf *b;
1.101 markus 1954: struct stat st;
1.100 markus 1955: pid_t pid;
1.304 deraadt 1956: int r, to[2], from[2], status;
1.295 djm 1957: int sock = ssh_packet_get_connection_in(ssh);
1.223 djm 1958: u_char rversion = 0, version = 2;
1959: void (*osigchld)(int);
1.100 markus 1960:
1.223 djm 1961: *sigp = NULL;
1962: *lenp = 0;
1.100 markus 1963:
1.306 deraadt 1964: if (stat(_PATH_SSH_KEY_SIGN, &st) == -1) {
1.331 djm 1965: error_f("not installed: %s", strerror(errno));
1.223 djm 1966: return -1;
1967: }
1968: if (fflush(stdout) != 0) {
1.331 djm 1969: error_f("fflush: %s", strerror(errno));
1.101 markus 1970: return -1;
1971: }
1.306 deraadt 1972: if (pipe(to) == -1) {
1.331 djm 1973: error_f("pipe: %s", strerror(errno));
1.100 markus 1974: return -1;
1975: }
1.306 deraadt 1976: if (pipe(from) == -1) {
1.331 djm 1977: error_f("pipe: %s", strerror(errno));
1.100 markus 1978: return -1;
1979: }
1.306 deraadt 1980: if ((pid = fork()) == -1) {
1.331 djm 1981: error_f("fork: %s", strerror(errno));
1.100 markus 1982: return -1;
1983: }
1.317 dtucker 1984: osigchld = ssh_signal(SIGCHLD, SIG_DFL);
1.100 markus 1985: if (pid == 0) {
1986: close(from[0]);
1.306 deraadt 1987: if (dup2(from[1], STDOUT_FILENO) == -1)
1.331 djm 1988: fatal_f("dup2: %s", strerror(errno));
1.100 markus 1989: close(to[1]);
1.306 deraadt 1990: if (dup2(to[0], STDIN_FILENO) == -1)
1.331 djm 1991: fatal_f("dup2: %s", strerror(errno));
1.103 markus 1992: close(from[1]);
1993: close(to[0]);
1.304 deraadt 1994:
1.306 deraadt 1995: if (dup2(sock, STDERR_FILENO + 1) == -1)
1.331 djm 1996: fatal_f("dup2: %s", strerror(errno));
1.304 deraadt 1997: sock = STDERR_FILENO + 1;
1998: fcntl(sock, F_SETFD, 0); /* keep the socket on exec */
1.223 djm 1999: closefrom(sock + 1);
1.304 deraadt 2000:
1.331 djm 2001: debug3_f("[child] pid=%ld, exec %s",
2002: (long)getpid(), _PATH_SSH_KEY_SIGN);
1.233 mmcc 2003: execl(_PATH_SSH_KEY_SIGN, _PATH_SSH_KEY_SIGN, (char *)NULL);
1.331 djm 2004: fatal_f("exec(%s): %s", _PATH_SSH_KEY_SIGN,
1.100 markus 2005: strerror(errno));
2006: }
2007: close(from[1]);
2008: close(to[0]);
1.305 djm 2009: sock = STDERR_FILENO + 1;
1.100 markus 2010:
1.223 djm 2011: if ((b = sshbuf_new()) == NULL)
1.331 djm 2012: fatal_f("sshbuf_new failed");
1.223 djm 2013: /* send # of sock, data to be signed */
1.253 djm 2014: if ((r = sshbuf_put_u32(b, sock)) != 0 ||
1.223 djm 2015: (r = sshbuf_put_string(b, data, datalen)) != 0)
1.331 djm 2016: fatal_fr(r, "buffer error");
1.223 djm 2017: if (ssh_msg_send(to[1], version, b) == -1)
1.331 djm 2018: fatal_f("couldn't send request");
1.223 djm 2019: sshbuf_reset(b);
2020: r = ssh_msg_recv(from[0], b);
1.101 markus 2021: close(from[0]);
2022: close(to[1]);
1.223 djm 2023: if (r < 0) {
1.331 djm 2024: error_f("no reply");
1.223 djm 2025: goto fail;
2026: }
1.101 markus 2027:
1.223 djm 2028: errno = 0;
1.306 deraadt 2029: while (waitpid(pid, &status, 0) == -1) {
1.223 djm 2030: if (errno != EINTR) {
1.331 djm 2031: error_f("waitpid %ld: %s", (long)pid, strerror(errno));
1.223 djm 2032: goto fail;
2033: }
2034: }
2035: if (!WIFEXITED(status)) {
1.331 djm 2036: error_f("exited abnormally");
1.223 djm 2037: goto fail;
2038: }
2039: if (WEXITSTATUS(status) != 0) {
1.331 djm 2040: error_f("exited with status %d", WEXITSTATUS(status));
1.223 djm 2041: goto fail;
2042: }
2043: if ((r = sshbuf_get_u8(b, &rversion)) != 0) {
1.331 djm 2044: error_fr(r, "buffer error");
1.223 djm 2045: goto fail;
2046: }
2047: if (rversion != version) {
1.331 djm 2048: error_f("bad version");
1.223 djm 2049: goto fail;
2050: }
2051: if ((r = sshbuf_get_string(b, sigp, lenp)) != 0) {
1.331 djm 2052: error_fr(r, "buffer error");
1.223 djm 2053: fail:
1.317 dtucker 2054: ssh_signal(SIGCHLD, osigchld);
1.223 djm 2055: sshbuf_free(b);
1.100 markus 2056: return -1;
2057: }
1.317 dtucker 2058: ssh_signal(SIGCHLD, osigchld);
1.223 djm 2059: sshbuf_free(b);
1.100 markus 2060:
2061: return 0;
2062: }
2063:
1.302 djm 2064: static int
1.295 djm 2065: userauth_hostbased(struct ssh *ssh)
1.68 markus 2066: {
1.295 djm 2067: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.223 djm 2068: struct sshkey *private = NULL;
2069: struct sshbuf *b = NULL;
2070: u_char *sig = NULL, *keyblob = NULL;
2071: char *fp = NULL, *chost = NULL, *lname = NULL;
2072: size_t siglen = 0, keylen = 0;
2073: int i, r, success = 0;
2074:
2075: if (authctxt->ktypes == NULL) {
2076: authctxt->oktypes = xstrdup(options.hostbased_key_types);
2077: authctxt->ktypes = authctxt->oktypes;
2078: }
1.213 djm 2079:
1.223 djm 2080: /*
2081: * Work through each listed type pattern in HostbasedKeyTypes,
2082: * trying each hostkey that matches the type in turn.
2083: */
2084: for (;;) {
2085: if (authctxt->active_ktype == NULL)
2086: authctxt->active_ktype = strsep(&authctxt->ktypes, ",");
2087: if (authctxt->active_ktype == NULL ||
2088: *authctxt->active_ktype == '\0')
2089: break;
1.331 djm 2090: debug3_f("trying key type %s", authctxt->active_ktype);
1.68 markus 2091:
1.223 djm 2092: /* check for a useful key */
2093: private = NULL;
2094: for (i = 0; i < authctxt->sensitive->nkeys; i++) {
2095: if (authctxt->sensitive->keys[i] == NULL ||
2096: authctxt->sensitive->keys[i]->type == KEY_UNSPEC)
2097: continue;
2098: if (match_pattern_list(
2099: sshkey_ssh_name(authctxt->sensitive->keys[i]),
1.224 djm 2100: authctxt->active_ktype, 0) != 1)
1.223 djm 2101: continue;
1.68 markus 2102: /* we take and free the key */
1.223 djm 2103: private = authctxt->sensitive->keys[i];
2104: authctxt->sensitive->keys[i] = NULL;
1.68 markus 2105: break;
2106: }
1.223 djm 2107: /* Found one */
2108: if (private != NULL)
2109: break;
2110: /* No more keys of this type; advance */
2111: authctxt->active_ktype = NULL;
1.68 markus 2112: }
1.223 djm 2113: if (private == NULL) {
2114: free(authctxt->oktypes);
2115: authctxt->oktypes = authctxt->ktypes = NULL;
2116: authctxt->active_ktype = NULL;
1.109 markus 2117: debug("No more client hostkeys for hostbased authentication.");
1.223 djm 2118: goto out;
1.68 markus 2119: }
1.211 djm 2120:
1.223 djm 2121: if ((fp = sshkey_fingerprint(private, options.fingerprint_hash,
2122: SSH_FP_DEFAULT)) == NULL) {
1.331 djm 2123: error_f("sshkey_fingerprint failed");
1.223 djm 2124: goto out;
1.68 markus 2125: }
1.331 djm 2126: debug_f("trying hostkey %s %s", sshkey_ssh_name(private), fp);
1.211 djm 2127:
1.84 markus 2128: /* figure out a name for the client host */
1.295 djm 2129: lname = get_local_name(ssh_packet_get_connection_in(ssh));
2130: if (lname == NULL) {
1.331 djm 2131: error_f("cannot get local ipaddr/name");
1.223 djm 2132: goto out;
1.84 markus 2133: }
1.223 djm 2134:
2135: /* XXX sshbuf_put_stringf? */
2136: xasprintf(&chost, "%s.", lname);
1.331 djm 2137: debug2_f("chost %s", chost);
1.84 markus 2138:
1.68 markus 2139: /* construct data */
1.223 djm 2140: if ((b = sshbuf_new()) == NULL) {
1.331 djm 2141: error_f("sshbuf_new failed");
1.223 djm 2142: goto out;
2143: }
2144: if ((r = sshkey_to_blob(private, &keyblob, &keylen)) != 0) {
1.331 djm 2145: error_fr(r, "sshkey_to_blob");
1.223 djm 2146: goto out;
2147: }
2148: if ((r = sshbuf_put_string(b, session_id2, session_id2_len)) != 0 ||
2149: (r = sshbuf_put_u8(b, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
2150: (r = sshbuf_put_cstring(b, authctxt->server_user)) != 0 ||
1.267 djm 2151: (r = sshbuf_put_cstring(b, authctxt->service)) != 0 ||
1.223 djm 2152: (r = sshbuf_put_cstring(b, authctxt->method->name)) != 0 ||
1.279 markus 2153: (r = sshbuf_put_cstring(b, sshkey_ssh_name(private))) != 0 ||
1.223 djm 2154: (r = sshbuf_put_string(b, keyblob, keylen)) != 0 ||
2155: (r = sshbuf_put_cstring(b, chost)) != 0 ||
2156: (r = sshbuf_put_cstring(b, authctxt->local_user)) != 0) {
1.331 djm 2157: error_fr(r, "buffer error");
1.223 djm 2158: goto out;
2159: }
2160:
1.68 markus 2161: #ifdef DEBUG_PK
1.223 djm 2162: sshbuf_dump(b, stderr);
1.68 markus 2163: #endif
1.294 djm 2164: if ((r = ssh_keysign(ssh, private, &sig, &siglen,
2165: sshbuf_ptr(b), sshbuf_len(b))) != 0) {
1.223 djm 2166: error("sign using hostkey %s %s failed",
2167: sshkey_ssh_name(private), fp);
2168: goto out;
2169: }
2170: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
2171: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
2172: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
2173: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1.279 markus 2174: (r = sshpkt_put_cstring(ssh, sshkey_ssh_name(private))) != 0 ||
1.223 djm 2175: (r = sshpkt_put_string(ssh, keyblob, keylen)) != 0 ||
2176: (r = sshpkt_put_cstring(ssh, chost)) != 0 ||
2177: (r = sshpkt_put_cstring(ssh, authctxt->local_user)) != 0 ||
2178: (r = sshpkt_put_string(ssh, sig, siglen)) != 0 ||
2179: (r = sshpkt_send(ssh)) != 0) {
1.331 djm 2180: error_fr(r, "packet error");
1.223 djm 2181: goto out;
2182: }
2183: success = 1;
2184:
2185: out:
1.278 markus 2186: if (sig != NULL)
2187: freezero(sig, siglen);
1.223 djm 2188: free(keyblob);
2189: free(lname);
2190: free(fp);
1.197 djm 2191: free(chost);
1.223 djm 2192: sshkey_free(private);
2193: sshbuf_free(b);
1.68 markus 2194:
1.223 djm 2195: return success;
1.23 markus 2196: }
1.170 djm 2197:
1.20 markus 2198: /* find auth method */
2199:
2200: /*
2201: * given auth method name, if configurable options permit this method fill
2202: * in auth_ident field and return true, otherwise return false.
2203: */
1.76 itojun 2204: static int
1.20 markus 2205: authmethod_is_enabled(Authmethod *method)
2206: {
2207: if (method == NULL)
2208: return 0;
2209: /* return false if options indicate this method is disabled */
2210: if (method->enabled == NULL || *method->enabled == 0)
2211: return 0;
2212: /* return false if batch mode is enabled but method needs interactive mode */
2213: if (method->batch_flag != NULL && *method->batch_flag != 0)
2214: return 0;
2215: return 1;
2216: }
2217:
1.76 itojun 2218: static Authmethod *
1.20 markus 2219: authmethod_lookup(const char *name)
1.1 markus 2220: {
1.20 markus 2221: Authmethod *method = NULL;
2222: if (name != NULL)
2223: for (method = authmethods; method->name != NULL; method++)
2224: if (strcmp(name, method->name) == 0)
2225: return method;
2226: debug2("Unrecognized authentication method name: %s", name ? name : "NULL");
2227: return NULL;
2228: }
1.1 markus 2229:
1.53 markus 2230: /* XXX internal state */
2231: static Authmethod *current = NULL;
2232: static char *supported = NULL;
2233: static char *preferred = NULL;
1.105 deraadt 2234:
1.20 markus 2235: /*
2236: * Given the authentication method list sent by the server, return the
2237: * next method we should try. If the server initially sends a nil list,
1.67 markus 2238: * use a built-in default list.
1.41 stevesk 2239: */
1.76 itojun 2240: static Authmethod *
1.20 markus 2241: authmethod_get(char *authlist)
2242: {
1.53 markus 2243: char *name = NULL;
1.97 markus 2244: u_int next;
1.41 stevesk 2245:
1.20 markus 2246: /* Use a suitable default if we're passed a nil list. */
2247: if (authlist == NULL || strlen(authlist) == 0)
1.53 markus 2248: authlist = options.preferred_authentications;
1.20 markus 2249:
1.53 markus 2250: if (supported == NULL || strcmp(authlist, supported) != 0) {
2251: debug3("start over, passed a different list %s", authlist);
1.197 djm 2252: free(supported);
1.53 markus 2253: supported = xstrdup(authlist);
2254: preferred = options.preferred_authentications;
2255: debug3("preferred %s", preferred);
2256: current = NULL;
2257: } else if (current != NULL && authmethod_is_enabled(current))
2258: return current;
1.20 markus 2259:
1.53 markus 2260: for (;;) {
2261: if ((name = match_list(preferred, supported, &next)) == NULL) {
1.109 markus 2262: debug("No more authentication methods to try.");
1.53 markus 2263: current = NULL;
2264: return NULL;
2265: }
2266: preferred += next;
1.23 markus 2267: debug3("authmethod_lookup %s", name);
1.53 markus 2268: debug3("remaining preferred: %s", preferred);
2269: if ((current = authmethod_lookup(name)) != NULL &&
2270: authmethod_is_enabled(current)) {
1.23 markus 2271: debug3("authmethod_is_enabled %s", name);
1.109 markus 2272: debug("Next authentication method: %s", name);
1.197 djm 2273: free(name);
1.53 markus 2274: return current;
1.23 markus 2275: }
1.198 dtucker 2276: free(name);
1.1 markus 2277: }
1.53 markus 2278: }
1.1 markus 2279:
1.79 stevesk 2280: static char *
1.53 markus 2281: authmethods_get(void)
2282: {
2283: Authmethod *method = NULL;
1.278 markus 2284: struct sshbuf *b;
1.93 markus 2285: char *list;
1.278 markus 2286: int r;
1.27 provos 2287:
1.278 markus 2288: if ((b = sshbuf_new()) == NULL)
1.331 djm 2289: fatal_f("sshbuf_new failed");
1.53 markus 2290: for (method = authmethods; method->name != NULL; method++) {
2291: if (authmethod_is_enabled(method)) {
1.278 markus 2292: if ((r = sshbuf_putf(b, "%s%s",
2293: sshbuf_len(b) ? "," : "", method->name)) != 0)
1.331 djm 2294: fatal_fr(r, "buffer error");
1.53 markus 2295: }
2296: }
1.278 markus 2297: if ((list = sshbuf_dup_string(b)) == NULL)
1.331 djm 2298: fatal_f("sshbuf_dup_string failed");
1.278 markus 2299: sshbuf_free(b);
1.93 markus 2300: return list;
1.1 markus 2301: }