Annotation of src/usr.bin/ssh/sshconnect2.c, Revision 1.337
1.337 ! djm 1: /* $OpenBSD: sshconnect2.c,v 1.336 2020/11/13 07:30:44 djm Exp $ */
1.1 markus 2: /*
3: * Copyright (c) 2000 Markus Friedl. All rights reserved.
1.170 djm 4: * Copyright (c) 2008 Damien Miller. All rights reserved.
1.1 markus 5: *
6: * Redistribution and use in source and binary forms, with or without
7: * modification, are permitted provided that the following conditions
8: * are met:
9: * 1. Redistributions of source code must retain the above copyright
10: * notice, this list of conditions and the following disclaimer.
11: * 2. Redistributions in binary form must reproduce the above copyright
12: * notice, this list of conditions and the following disclaimer in the
13: * documentation and/or other materials provided with the distribution.
14: *
15: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25: */
26:
1.145 stevesk 27: #include <sys/types.h>
1.160 deraadt 28: #include <sys/socket.h>
1.145 stevesk 29: #include <sys/wait.h>
1.144 stevesk 30: #include <sys/queue.h>
1.146 stevesk 31: #include <sys/stat.h>
1.156 stevesk 32:
33: #include <errno.h>
1.174 dtucker 34: #include <fcntl.h>
1.336 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++)
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: }
1.326 djm 132: /*
133: * If a plain public key exists that matches the type of the best
134: * preference HostkeyAlgorithms, then use the whole list as is.
135: * Note that we ignore whether the best preference algorithm is a
136: * certificate type, as sshconnect.c will downgrade certs to
137: * plain keys if necessary.
138: */
139: best = first_alg(options.hostkeyalgorithms);
140: if (lookup_key_in_hostkeys_by_type(hostkeys,
1.328 djm 141: sshkey_type_plain(sshkey_type_from_name(best)),
142: sshkey_ecdsa_nid_from_name(best), NULL)) {
1.331 djm 143: debug3_f("have matching best-preference key type %s, "
144: "using HostkeyAlgorithms verbatim", best);
1.326 djm 145: ret = xstrdup(options.hostkeyalgorithms);
146: goto out;
147: }
148:
149: /*
150: * Otherwise, prefer the host key algorithms that match known keys
151: * while keeping the ordering of HostkeyAlgorithms as much as possible.
152: */
1.320 djm 153: oavail = avail = xstrdup(options.hostkeyalgorithms);
1.186 djm 154: maxlen = strlen(avail) + 1;
155: first = xmalloc(maxlen);
156: last = xmalloc(maxlen);
157: *first = *last = '\0';
158:
159: #define ALG_APPEND(to, from) \
160: do { \
161: if (*to != '\0') \
162: strlcat(to, ",", maxlen); \
163: strlcat(to, from, maxlen); \
164: } while (0)
165:
166: while ((alg = strsep(&avail, ",")) && *alg != '\0') {
1.214 djm 167: if ((ktype = sshkey_type_from_name(alg)) == KEY_UNSPEC)
1.331 djm 168: fatal_f("unknown alg %s", alg);
1.322 djm 169: /*
170: * If we have a @cert-authority marker in known_hosts then
171: * prefer all certificate algorithms.
172: */
173: if (sshkey_type_is_cert(ktype) &&
174: lookup_marker_in_hostkeys(hostkeys, MRK_CA)) {
175: ALG_APPEND(first, alg);
176: continue;
177: }
178: /* If the key appears in known_hosts then prefer it */
1.186 djm 179: if (lookup_key_in_hostkeys_by_type(hostkeys,
1.328 djm 180: sshkey_type_plain(ktype),
181: sshkey_ecdsa_nid_from_name(alg), NULL)) {
1.186 djm 182: ALG_APPEND(first, alg);
1.322 djm 183: continue;
184: }
185: /* Otherwise, put it last */
186: ALG_APPEND(last, alg);
1.186 djm 187: }
188: #undef ALG_APPEND
1.216 djm 189: xasprintf(&ret, "%s%s%s", first,
190: (*first == '\0' || *last == '\0') ? "" : ",", last);
1.186 djm 191: if (*first != '\0')
1.331 djm 192: debug3_f("prefer hostkeyalgs: %s", first);
1.186 djm 193:
1.326 djm 194: out:
195: free(best);
1.197 djm 196: free(first);
197: free(last);
198: free(hostname);
199: free(oavail);
1.186 djm 200: free_hostkeys(hostkeys);
201:
202: return ret;
203: }
204:
1.1 markus 205: void
1.291 djm 206: ssh_kex2(struct ssh *ssh, char *host, struct sockaddr *hostaddr, u_short port)
1.22 provos 207: {
1.205 markus 208: char *myproposal[PROPOSAL_MAX] = { KEX_CLIENT };
1.275 djm 209: char *s, *all_key;
1.320 djm 210: int r, use_known_hosts_order = 0;
1.61 markus 211:
212: xxx_host = host;
213: xxx_hostaddr = hostaddr;
1.22 provos 214:
1.320 djm 215: /*
216: * If the user has not specified HostkeyAlgorithms, or has only
217: * appended or removed algorithms from that list then prefer algorithms
218: * that are in the list that are supported by known_hosts keys.
219: */
220: if (options.hostkeyalgorithms == NULL ||
221: options.hostkeyalgorithms[0] == '-' ||
222: options.hostkeyalgorithms[0] == '+')
223: use_known_hosts_order = 1;
224:
225: /* Expand or fill in HostkeyAlgorithms */
226: all_key = sshkey_alg_list(0, 0, 1, ',');
1.333 djm 227: if ((r = kex_assemble_names(&options.hostkeyalgorithms,
228: kex_default_pk_alg(), all_key)) != 0)
229: fatal_fr(r, "kex_assemble_namelist");
1.320 djm 230: free(all_key);
231:
1.231 markus 232: if ((s = kex_names_cat(options.kex_algorithms, "ext-info-c")) == NULL)
1.331 djm 233: fatal_f("kex_names_cat");
1.284 djm 234: myproposal[PROPOSAL_KEX_ALGS] = compat_kex_proposal(s);
1.60 stevesk 235: myproposal[PROPOSAL_ENC_ALGS_CTOS] =
1.284 djm 236: compat_cipher_proposal(options.ciphers);
1.60 stevesk 237: myproposal[PROPOSAL_ENC_ALGS_STOC] =
1.284 djm 238: compat_cipher_proposal(options.ciphers);
1.245 dtucker 239: myproposal[PROPOSAL_COMP_ALGS_CTOS] =
1.318 dtucker 240: myproposal[PROPOSAL_COMP_ALGS_STOC] =
241: (char *)compression_alg_list(options.compression);
1.226 djm 242: myproposal[PROPOSAL_MAC_ALGS_CTOS] =
243: myproposal[PROPOSAL_MAC_ALGS_STOC] = options.macs;
1.320 djm 244: if (use_known_hosts_order) {
245: /* Query known_hosts and prefer algorithms that appear there */
1.88 deraadt 246: myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] =
1.320 djm 247: compat_pkalg_proposal(
248: order_hostkeyalgs(host, hostaddr, port));
1.226 djm 249: } else {
1.320 djm 250: /* Use specified HostkeyAlgorithms exactly */
1.186 djm 251: myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] =
1.320 djm 252: compat_pkalg_proposal(options.hostkeyalgorithms);
1.186 djm 253: }
1.115 markus 254:
1.196 dtucker 255: if (options.rekey_limit || options.rekey_interval)
1.294 djm 256: ssh_packet_set_rekey_limits(ssh, options.rekey_limit,
1.254 dtucker 257: options.rekey_interval);
1.22 provos 258:
1.65 markus 259: /* start key exchange */
1.291 djm 260: if ((r = kex_setup(ssh, myproposal)) != 0)
1.331 djm 261: fatal_r(r, "kex_setup");
1.207 markus 262: #ifdef WITH_OPENSSL
1.301 djm 263: ssh->kex->kex[KEX_DH_GRP1_SHA1] = kex_gen_client;
264: ssh->kex->kex[KEX_DH_GRP14_SHA1] = kex_gen_client;
265: ssh->kex->kex[KEX_DH_GRP14_SHA256] = kex_gen_client;
266: ssh->kex->kex[KEX_DH_GRP16_SHA512] = kex_gen_client;
267: ssh->kex->kex[KEX_DH_GRP18_SHA512] = kex_gen_client;
1.291 djm 268: ssh->kex->kex[KEX_DH_GEX_SHA1] = kexgex_client;
269: ssh->kex->kex[KEX_DH_GEX_SHA256] = kexgex_client;
1.301 djm 270: ssh->kex->kex[KEX_ECDH_SHA2] = kex_gen_client;
1.207 markus 271: #endif
1.301 djm 272: ssh->kex->kex[KEX_C25519_SHA256] = kex_gen_client;
273: ssh->kex->kex[KEX_KEM_SNTRUP4591761X25519_SHA512] = kex_gen_client;
1.291 djm 274: ssh->kex->verify_host_key=&verify_host_key_callback;
1.22 provos 275:
1.291 djm 276: ssh_dispatch_run_fatal(ssh, DISPATCH_BLOCK, &ssh->kex->done);
1.173 andreas 277:
1.231 markus 278: /* remove ext-info from the KEX proposals for rekeying */
279: myproposal[PROPOSAL_KEX_ALGS] =
1.284 djm 280: compat_kex_proposal(options.kex_algorithms);
1.291 djm 281: if ((r = kex_prop2buf(ssh->kex->my, myproposal)) != 0)
1.331 djm 282: fatal_r(r, "kex_prop2buf");
1.62 markus 283:
1.291 djm 284: session_id2 = ssh->kex->session_id;
285: session_id2_len = ssh->kex->session_id_len;
1.22 provos 286:
287: #ifdef DEBUG_KEXDH
288: /* send 1st encrypted/maced/compressed message */
1.278 markus 289: if ((r = sshpkt_start(ssh, SSH2_MSG_IGNORE)) != 0 ||
290: (r = sshpkt_put_cstring(ssh, "markus")) != 0 ||
1.280 markus 291: (r = sshpkt_send(ssh)) != 0 ||
292: (r = ssh_packet_write_wait(ssh)) != 0)
1.331 djm 293: fatal_fr(r, "send packet");
1.22 provos 294: #endif
1.1 markus 295: }
1.11 markus 296:
1.1 markus 297: /*
298: * Authenticate user
299: */
1.20 markus 300:
1.214 djm 301: typedef struct cauthctxt Authctxt;
302: typedef struct cauthmethod Authmethod;
1.117 markus 303: typedef struct identity Identity;
304: typedef struct idlist Idlist;
1.20 markus 305:
1.117 markus 306: struct identity {
307: TAILQ_ENTRY(identity) next;
1.214 djm 308: int agent_fd; /* >=0 if agent supports key */
309: struct sshkey *key; /* public/private key */
1.117 markus 310: char *filename; /* comment for agent-only keys */
311: int tried;
312: int isprivate; /* key points to the private key */
1.191 dtucker 313: int userprovided;
1.117 markus 314: };
315: TAILQ_HEAD(idlist, identity);
1.20 markus 316:
1.214 djm 317: struct cauthctxt {
1.20 markus 318: const char *server_user;
1.68 markus 319: const char *local_user;
1.20 markus 320: const char *host;
321: const char *service;
1.214 djm 322: struct cauthmethod *method;
1.183 djm 323: sig_atomic_t success;
1.51 markus 324: char *authlist;
1.302 djm 325: #ifdef GSSAPI
326: /* gssapi */
327: gss_OID_set gss_supported_mechs;
328: u_int mech_tried;
329: #endif
1.68 markus 330: /* pubkey */
1.214 djm 331: struct idlist keys;
332: int agent_fd;
1.68 markus 333: /* hostbased */
1.100 markus 334: Sensitive *sensitive;
1.223 djm 335: char *oktypes, *ktypes;
336: const char *active_ktype;
1.82 markus 337: /* kbd-interactive */
338: int info_req_seen;
1.292 djm 339: int attempt_kbdint;
340: /* password */
341: int attempt_passwd;
1.121 markus 342: /* generic */
343: void *methoddata;
1.20 markus 344: };
1.214 djm 345:
346: struct cauthmethod {
1.20 markus 347: char *name; /* string to compare against server's list */
1.295 djm 348: int (*userauth)(struct ssh *ssh);
349: void (*cleanup)(struct ssh *ssh);
1.20 markus 350: int *enabled; /* flag in option struct that enables method */
351: int *batch_flag; /* flag in option struct that disables method */
352: };
353:
1.302 djm 354: static int input_userauth_service_accept(int, u_int32_t, struct ssh *);
355: static int input_userauth_ext_info(int, u_int32_t, struct ssh *);
356: static int input_userauth_success(int, u_int32_t, struct ssh *);
357: static int input_userauth_failure(int, u_int32_t, struct ssh *);
358: static int input_userauth_banner(int, u_int32_t, struct ssh *);
359: static int input_userauth_error(int, u_int32_t, struct ssh *);
360: static int input_userauth_info_req(int, u_int32_t, struct ssh *);
361: static int input_userauth_pk_ok(int, u_int32_t, struct ssh *);
362: static int input_userauth_passwd_changereq(int, u_int32_t, struct ssh *);
363:
364: static int userauth_none(struct ssh *);
365: static int userauth_pubkey(struct ssh *);
366: static int userauth_passwd(struct ssh *);
367: static int userauth_kbdint(struct ssh *);
368: static int userauth_hostbased(struct ssh *);
1.20 markus 369:
1.121 markus 370: #ifdef GSSAPI
1.302 djm 371: static int userauth_gssapi(struct ssh *);
372: static void userauth_gssapi_cleanup(struct ssh *);
373: static int input_gssapi_response(int type, u_int32_t, struct ssh *);
374: static int input_gssapi_token(int type, u_int32_t, struct ssh *);
375: static int input_gssapi_error(int, u_int32_t, struct ssh *);
376: static int input_gssapi_errtok(int, u_int32_t, struct ssh *);
1.121 markus 377: #endif
378:
1.295 djm 379: void userauth(struct ssh *, char *);
1.51 markus 380:
1.303 djm 381: static void pubkey_cleanup(struct ssh *);
1.295 djm 382: static int sign_and_send_pubkey(struct ssh *ssh, Identity *);
1.117 markus 383: static void pubkey_prepare(Authctxt *);
1.251 djm 384: static void pubkey_reset(Authctxt *);
1.259 markus 385: static struct sshkey *load_identity_file(Identity *);
1.76 itojun 386:
387: static Authmethod *authmethod_get(char *authlist);
388: static Authmethod *authmethod_lookup(const char *name);
389: static char *authmethods_get(void);
1.20 markus 390:
391: Authmethod authmethods[] = {
1.121 markus 392: #ifdef GSSAPI
1.132 markus 393: {"gssapi-with-mic",
1.121 markus 394: userauth_gssapi,
1.302 djm 395: userauth_gssapi_cleanup,
1.121 markus 396: &options.gss_authentication,
397: NULL},
398: #endif
1.81 markus 399: {"hostbased",
400: userauth_hostbased,
1.170 djm 401: NULL,
1.81 markus 402: &options.hostbased_authentication,
403: NULL},
1.20 markus 404: {"publickey",
405: userauth_pubkey,
1.303 djm 406: NULL,
1.28 markus 407: &options.pubkey_authentication,
1.20 markus 408: NULL},
1.81 markus 409: {"keyboard-interactive",
410: userauth_kbdint,
1.170 djm 411: NULL,
1.81 markus 412: &options.kbd_interactive_authentication,
413: &options.batch_mode},
1.20 markus 414: {"password",
415: userauth_passwd,
1.170 djm 416: NULL,
1.20 markus 417: &options.password_authentication,
1.23 markus 418: &options.batch_mode},
419: {"none",
420: userauth_none,
421: NULL,
1.170 djm 422: NULL,
1.23 markus 423: NULL},
1.170 djm 424: {NULL, NULL, NULL, NULL, NULL}
1.20 markus 425: };
426:
427: void
1.291 djm 428: ssh_userauth2(struct ssh *ssh, const char *local_user,
429: const char *server_user, char *host, Sensitive *sensitive)
1.20 markus 430: {
431: Authctxt authctxt;
1.231 markus 432: int r;
1.39 markus 433:
1.73 markus 434: if (options.challenge_response_authentication)
1.39 markus 435: options.kbd_interactive_authentication = 1;
1.53 markus 436: if (options.preferred_authentications == NULL)
437: options.preferred_authentications = authmethods_get();
438:
1.20 markus 439: /* setup authentication context */
1.82 markus 440: memset(&authctxt, 0, sizeof(authctxt));
1.20 markus 441: authctxt.server_user = server_user;
1.68 markus 442: authctxt.local_user = local_user;
1.20 markus 443: authctxt.host = host;
444: authctxt.service = "ssh-connection"; /* service name */
445: authctxt.success = 0;
1.23 markus 446: authctxt.method = authmethod_lookup("none");
1.51 markus 447: authctxt.authlist = NULL;
1.121 markus 448: authctxt.methoddata = NULL;
1.100 markus 449: authctxt.sensitive = sensitive;
1.223 djm 450: authctxt.active_ktype = authctxt.oktypes = authctxt.ktypes = NULL;
1.82 markus 451: authctxt.info_req_seen = 0;
1.292 djm 452: authctxt.attempt_kbdint = 0;
453: authctxt.attempt_passwd = 0;
1.302 djm 454: #if GSSAPI
455: authctxt.gss_supported_mechs = NULL;
456: authctxt.mech_tried = 0;
457: #endif
1.215 djm 458: authctxt.agent_fd = -1;
1.289 djm 459: pubkey_prepare(&authctxt);
1.291 djm 460: if (authctxt.method == NULL) {
1.331 djm 461: fatal_f("internal error: cannot send userauth none request");
1.291 djm 462: }
1.20 markus 463:
1.231 markus 464: if ((r = sshpkt_start(ssh, SSH2_MSG_SERVICE_REQUEST)) != 0 ||
465: (r = sshpkt_put_cstring(ssh, "ssh-userauth")) != 0 ||
466: (r = sshpkt_send(ssh)) != 0)
1.331 djm 467: fatal_fr(r, "send packet");
1.231 markus 468:
1.260 markus 469: ssh->authctxt = &authctxt;
1.231 markus 470: ssh_dispatch_init(ssh, &input_userauth_error);
471: ssh_dispatch_set(ssh, SSH2_MSG_EXT_INFO, &input_userauth_ext_info);
472: ssh_dispatch_set(ssh, SSH2_MSG_SERVICE_ACCEPT, &input_userauth_service_accept);
1.263 markus 473: ssh_dispatch_run_fatal(ssh, DISPATCH_BLOCK, &authctxt.success); /* loop until success */
1.303 djm 474: pubkey_cleanup(ssh);
1.260 markus 475: ssh->authctxt = NULL;
1.20 markus 476:
1.231 markus 477: ssh_dispatch_range(ssh, SSH2_MSG_USERAUTH_MIN, SSH2_MSG_USERAUTH_MAX, NULL);
1.119 markus 478:
1.248 dtucker 479: if (!authctxt.success)
480: fatal("Authentication failed.");
1.109 markus 481: debug("Authentication succeeded (%s).", authctxt.method->name);
1.20 markus 482: }
1.119 markus 483:
1.231 markus 484: /* ARGSUSED */
1.302 djm 485: static int
1.261 markus 486: input_userauth_service_accept(int type, u_int32_t seq, struct ssh *ssh)
1.231 markus 487: {
488: int r;
489:
490: if (ssh_packet_remaining(ssh) > 0) {
491: char *reply;
492:
493: if ((r = sshpkt_get_cstring(ssh, &reply, NULL)) != 0)
494: goto out;
495: debug2("service_accept: %s", reply);
496: free(reply);
497: } else {
498: debug2("buggy server: service_accept w/o service");
499: }
500: if ((r = sshpkt_get_end(ssh)) != 0)
501: goto out;
502: debug("SSH2_MSG_SERVICE_ACCEPT received");
503:
504: /* initial userauth request */
1.295 djm 505: userauth_none(ssh);
1.231 markus 506:
507: ssh_dispatch_set(ssh, SSH2_MSG_EXT_INFO, &input_userauth_error);
508: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_SUCCESS, &input_userauth_success);
509: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_FAILURE, &input_userauth_failure);
510: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_BANNER, &input_userauth_banner);
511: r = 0;
512: out:
513: return r;
514: }
515:
516: /* ARGSUSED */
1.302 djm 517: static int
1.261 markus 518: input_userauth_ext_info(int type, u_int32_t seqnr, struct ssh *ssh)
1.231 markus 519: {
1.261 markus 520: return kex_input_ext_info(type, seqnr, ssh);
1.231 markus 521: }
522:
1.20 markus 523: void
1.295 djm 524: userauth(struct ssh *ssh, char *authlist)
1.51 markus 525: {
1.295 djm 526: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.278 markus 527:
1.170 djm 528: if (authctxt->method != NULL && authctxt->method->cleanup != NULL)
1.295 djm 529: authctxt->method->cleanup(ssh);
1.170 djm 530:
1.197 djm 531: free(authctxt->methoddata);
532: authctxt->methoddata = NULL;
1.51 markus 533: if (authlist == NULL) {
534: authlist = authctxt->authlist;
535: } else {
1.197 djm 536: free(authctxt->authlist);
1.51 markus 537: authctxt->authlist = authlist;
538: }
539: for (;;) {
540: Authmethod *method = authmethod_get(authlist);
541: if (method == NULL)
1.264 dtucker 542: fatal("%s@%s: Permission denied (%s).",
543: authctxt->server_user, authctxt->host, authlist);
1.51 markus 544: authctxt->method = method;
1.119 markus 545:
546: /* reset the per method handler */
1.278 markus 547: ssh_dispatch_range(ssh, SSH2_MSG_USERAUTH_PER_METHOD_MIN,
1.119 markus 548: SSH2_MSG_USERAUTH_PER_METHOD_MAX, NULL);
549:
550: /* and try new method */
1.295 djm 551: if (method->userauth(ssh) != 0) {
1.51 markus 552: debug2("we sent a %s packet, wait for reply", method->name);
553: break;
554: } else {
555: debug2("we did not send a packet, disable method");
556: method->enabled = NULL;
557: }
558: }
559: }
1.105 deraadt 560:
1.169 djm 561: /* ARGSUSED */
1.302 djm 562: static int
1.261 markus 563: input_userauth_error(int type, u_int32_t seq, struct ssh *ssh)
1.20 markus 564: {
1.331 djm 565: fatal_f("bad message during authentication: type %d", type);
1.218 markus 566: return 0;
1.35 markus 567: }
1.105 deraadt 568:
1.169 djm 569: /* ARGSUSED */
1.302 djm 570: static int
1.261 markus 571: input_userauth_banner(int type, u_int32_t seq, struct ssh *ssh)
1.35 markus 572: {
1.295 djm 573: char *msg = NULL;
1.294 djm 574: size_t len;
575: int r;
1.126 deraadt 576:
1.331 djm 577: debug3_f("entering");
1.294 djm 578: if ((r = sshpkt_get_cstring(ssh, &msg, &len)) != 0 ||
1.295 djm 579: (r = sshpkt_get_cstring(ssh, NULL, NULL)) != 0)
1.294 djm 580: goto out;
1.246 djm 581: if (len > 0 && options.log_level >= SYSLOG_LEVEL_INFO)
582: fmprintf(stderr, "%s", msg);
1.294 djm 583: r = 0;
584: out:
1.246 djm 585: free(msg);
1.294 djm 586: return r;
1.20 markus 587: }
1.105 deraadt 588:
1.169 djm 589: /* ARGSUSED */
1.302 djm 590: static int
1.261 markus 591: input_userauth_success(int type, u_int32_t seq, struct ssh *ssh)
1.20 markus 592: {
1.260 markus 593: Authctxt *authctxt = ssh->authctxt;
1.172 djm 594:
1.20 markus 595: if (authctxt == NULL)
1.331 djm 596: fatal_f("no authentication context");
1.197 djm 597: free(authctxt->authlist);
598: authctxt->authlist = NULL;
1.172 djm 599: if (authctxt->method != NULL && authctxt->method->cleanup != NULL)
1.295 djm 600: authctxt->method->cleanup(ssh);
1.197 djm 601: free(authctxt->methoddata);
602: authctxt->methoddata = NULL;
1.20 markus 603: authctxt->success = 1; /* break out */
1.218 markus 604: return 0;
1.20 markus 605: }
1.105 deraadt 606:
1.302 djm 607: #if 0
608: static int
1.261 markus 609: input_userauth_success_unexpected(int type, u_int32_t seq, struct ssh *ssh)
1.172 djm 610: {
1.260 markus 611: Authctxt *authctxt = ssh->authctxt;
1.172 djm 612:
613: if (authctxt == NULL)
1.331 djm 614: fatal_f("no authentication context");
1.172 djm 615:
616: fatal("Unexpected authentication success during %s.",
617: authctxt->method->name);
1.218 markus 618: return 0;
1.172 djm 619: }
1.302 djm 620: #endif
1.172 djm 621:
1.169 djm 622: /* ARGSUSED */
1.302 djm 623: static int
1.261 markus 624: input_userauth_failure(int type, u_int32_t seq, struct ssh *ssh)
1.20 markus 625: {
1.260 markus 626: Authctxt *authctxt = ssh->authctxt;
1.20 markus 627: char *authlist = NULL;
1.278 markus 628: u_char partial;
1.20 markus 629:
630: if (authctxt == NULL)
631: fatal("input_userauth_failure: no authentication context");
632:
1.307 dtucker 633: if (sshpkt_get_cstring(ssh, &authlist, NULL) != 0 ||
634: sshpkt_get_u8(ssh, &partial) != 0 ||
635: sshpkt_get_end(ssh) != 0)
1.278 markus 636: goto out;
1.20 markus 637:
1.193 markus 638: if (partial != 0) {
1.247 dtucker 639: verbose("Authenticated with partial success.");
1.193 markus 640: /* reset state */
1.251 djm 641: pubkey_reset(authctxt);
1.193 markus 642: }
1.109 markus 643: debug("Authentications that can continue: %s", authlist);
1.20 markus 644:
1.295 djm 645: userauth(ssh, authlist);
1.278 markus 646: authlist = NULL;
647: out:
648: free(authlist);
1.218 markus 649: return 0;
1.51 markus 650: }
1.169 djm 651:
1.287 djm 652: /*
653: * Format an identity for logging including filename, key type, fingerprint
654: * and location (agent, etc.). Caller must free.
655: */
656: static char *
657: format_identity(Identity *id)
658: {
659: char *fp = NULL, *ret = NULL;
1.309 djm 660: const char *note = "";
1.287 djm 661:
662: if (id->key != NULL) {
663: fp = sshkey_fingerprint(id->key, options.fingerprint_hash,
664: SSH_FP_DEFAULT);
665: }
1.309 djm 666: if (id->key) {
667: if ((id->key->flags & SSHKEY_FLAG_EXT) != 0)
668: note = " token";
1.311 markus 669: else if (sshkey_is_sk(id->key))
1.319 naddy 670: note = " authenticator";
1.309 djm 671: }
1.287 djm 672: xasprintf(&ret, "%s %s%s%s%s%s%s",
673: id->filename,
674: id->key ? sshkey_type(id->key) : "", id->key ? " " : "",
675: fp ? fp : "",
1.309 djm 676: id->userprovided ? " explicit" : "", note,
1.287 djm 677: id->agent_fd != -1 ? " agent" : "");
678: free(fp);
679: return ret;
680: }
681:
1.169 djm 682: /* ARGSUSED */
1.302 djm 683: static int
1.261 markus 684: input_userauth_pk_ok(int type, u_int32_t seq, struct ssh *ssh)
1.51 markus 685: {
1.260 markus 686: Authctxt *authctxt = ssh->authctxt;
1.259 markus 687: struct sshkey *key = NULL;
1.117 markus 688: Identity *id = NULL;
1.287 djm 689: int pktype, found = 0, sent = 0;
1.278 markus 690: size_t blen;
1.287 djm 691: char *pkalg = NULL, *fp = NULL, *ident = NULL;
1.278 markus 692: u_char *pkblob = NULL;
693: int r;
1.51 markus 694:
695: if (authctxt == NULL)
696: fatal("input_userauth_pk_ok: no authentication context");
1.267 djm 697:
1.278 markus 698: if ((r = sshpkt_get_cstring(ssh, &pkalg, NULL)) != 0 ||
699: (r = sshpkt_get_string(ssh, &pkblob, &blen)) != 0 ||
700: (r = sshpkt_get_end(ssh)) != 0)
701: goto done;
1.51 markus 702:
1.278 markus 703: if ((pktype = sshkey_type_from_name(pkalg)) == KEY_UNSPEC) {
1.331 djm 704: debug_f("server sent unknown pkalg %s", pkalg);
1.117 markus 705: goto done;
706: }
1.278 markus 707: if ((r = sshkey_from_blob(pkblob, blen, &key)) != 0) {
1.331 djm 708: debug_r(r, "no key from blob. pkalg %s", pkalg);
1.117 markus 709: goto done;
710: }
711: if (key->type != pktype) {
712: error("input_userauth_pk_ok: type mismatch "
713: "for decoded key (received %d, expected %d)",
714: key->type, pktype);
715: goto done;
716: }
717:
1.127 markus 718: /*
719: * search keys in the reverse order, because last candidate has been
720: * moved to the end of the queue. this also avoids confusion by
721: * duplicate keys
722: */
1.136 henning 723: TAILQ_FOREACH_REVERSE(id, &authctxt->keys, idlist, next) {
1.278 markus 724: if (sshkey_equal(key, id->key)) {
1.287 djm 725: found = 1;
1.51 markus 726: break;
727: }
1.117 markus 728: }
1.287 djm 729: if (!found || id == NULL) {
730: fp = sshkey_fingerprint(key, options.fingerprint_hash,
731: SSH_FP_DEFAULT);
1.331 djm 732: error_f("server replied with unknown key: %s %s",
1.287 djm 733: sshkey_type(key), fp == NULL ? "<ERROR>" : fp);
734: goto done;
735: }
736: ident = format_identity(id);
737: debug("Server accepts key: %s", ident);
1.295 djm 738: sent = sign_and_send_pubkey(ssh, id);
1.278 markus 739: r = 0;
740: done:
741: sshkey_free(key);
1.287 djm 742: free(ident);
743: free(fp);
1.197 djm 744: free(pkalg);
745: free(pkblob);
1.51 markus 746:
1.106 deraadt 747: /* try another method if we did not send a packet */
1.278 markus 748: if (r == 0 && sent == 0)
1.295 djm 749: userauth(ssh, NULL);
1.278 markus 750: return r;
1.20 markus 751: }
1.121 markus 752:
753: #ifdef GSSAPI
1.302 djm 754: static int
1.295 djm 755: userauth_gssapi(struct ssh *ssh)
1.121 markus 756: {
1.295 djm 757: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.121 markus 758: Gssctxt *gssctxt = NULL;
759: OM_uint32 min;
1.278 markus 760: int r, ok = 0;
1.302 djm 761: gss_OID mech = NULL;
1.121 markus 762:
763: /* Try one GSSAPI method at a time, rather than sending them all at
764: * once. */
765:
1.302 djm 766: if (authctxt->gss_supported_mechs == NULL)
767: gss_indicate_mechs(&min, &authctxt->gss_supported_mechs);
1.121 markus 768:
1.302 djm 769: /* Check to see whether the mechanism is usable before we offer it */
770: while (authctxt->mech_tried < authctxt->gss_supported_mechs->count &&
771: !ok) {
772: mech = &authctxt->gss_supported_mechs->
773: elements[authctxt->mech_tried];
1.121 markus 774: /* My DER encoding requires length<128 */
1.302 djm 775: if (mech->length < 128 && ssh_gssapi_check_mechanism(&gssctxt,
776: mech, authctxt->host)) {
1.121 markus 777: ok = 1; /* Mechanism works */
778: } else {
1.302 djm 779: authctxt->mech_tried++;
1.121 markus 780: }
781: }
782:
1.302 djm 783: if (!ok || mech == NULL)
1.139 djm 784: return 0;
1.121 markus 785:
786: authctxt->methoddata=(void *)gssctxt;
787:
1.278 markus 788: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
789: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
790: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
791: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
792: (r = sshpkt_put_u32(ssh, 1)) != 0 ||
1.302 djm 793: (r = sshpkt_put_u32(ssh, (mech->length) + 2)) != 0 ||
1.278 markus 794: (r = sshpkt_put_u8(ssh, SSH_GSS_OIDTYPE)) != 0 ||
1.302 djm 795: (r = sshpkt_put_u8(ssh, mech->length)) != 0 ||
796: (r = sshpkt_put(ssh, mech->elements, mech->length)) != 0 ||
1.278 markus 797: (r = sshpkt_send(ssh)) != 0)
1.331 djm 798: fatal_fr(r, "send packet");
1.278 markus 799:
800: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_RESPONSE, &input_gssapi_response);
801: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_TOKEN, &input_gssapi_token);
802: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_ERROR, &input_gssapi_error);
803: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_ERRTOK, &input_gssapi_errtok);
1.121 markus 804:
1.302 djm 805: authctxt->mech_tried++; /* Move along to next candidate */
1.121 markus 806:
807: return 1;
808: }
809:
1.302 djm 810: static void
811: userauth_gssapi_cleanup(struct ssh *ssh)
812: {
813: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
814: Gssctxt *gssctxt = (Gssctxt *)authctxt->methoddata;
815:
816: ssh_gssapi_delete_ctx(&gssctxt);
817: authctxt->methoddata = NULL;
818:
819: free(authctxt->gss_supported_mechs);
820: authctxt->gss_supported_mechs = NULL;
821: }
822:
1.130 markus 823: static OM_uint32
1.262 djm 824: process_gssapi_token(struct ssh *ssh, gss_buffer_t recv_tok)
1.130 markus 825: {
1.260 markus 826: Authctxt *authctxt = ssh->authctxt;
1.130 markus 827: Gssctxt *gssctxt = authctxt->methoddata;
828: gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
1.142 djm 829: gss_buffer_desc mic = GSS_C_EMPTY_BUFFER;
830: gss_buffer_desc gssbuf;
1.132 markus 831: OM_uint32 status, ms, flags;
1.278 markus 832: int r;
1.133 djm 833:
1.130 markus 834: status = ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
1.132 markus 835: recv_tok, &send_tok, &flags);
1.130 markus 836:
837: if (send_tok.length > 0) {
1.278 markus 838: u_char type = GSS_ERROR(status) ?
839: SSH2_MSG_USERAUTH_GSSAPI_ERRTOK :
840: SSH2_MSG_USERAUTH_GSSAPI_TOKEN;
841:
842: if ((r = sshpkt_start(ssh, type)) != 0 ||
843: (r = sshpkt_put_string(ssh, send_tok.value,
844: send_tok.length)) != 0 ||
845: (r = sshpkt_send(ssh)) != 0)
1.331 djm 846: fatal_fr(r, "send %u packet", type);
1.133 djm 847:
1.130 markus 848: gss_release_buffer(&ms, &send_tok);
849: }
1.133 djm 850:
1.130 markus 851: if (status == GSS_S_COMPLETE) {
1.132 markus 852: /* send either complete or MIC, depending on mechanism */
853: if (!(flags & GSS_C_INTEG_FLAG)) {
1.278 markus 854: if ((r = sshpkt_start(ssh,
855: SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE)) != 0 ||
856: (r = sshpkt_send(ssh)) != 0)
1.331 djm 857: fatal_fr(r, "send completion");
1.132 markus 858: } else {
1.278 markus 859: struct sshbuf *b;
860:
861: if ((b = sshbuf_new()) == NULL)
1.331 djm 862: fatal_f("sshbuf_new failed");
1.278 markus 863: ssh_gssapi_buildmic(b, authctxt->server_user,
1.132 markus 864: authctxt->service, "gssapi-with-mic");
865:
1.278 markus 866: if ((gssbuf.value = sshbuf_mutable_ptr(b)) == NULL)
1.331 djm 867: fatal_f("sshbuf_mutable_ptr failed");
1.278 markus 868: gssbuf.length = sshbuf_len(b);
1.133 djm 869:
1.132 markus 870: status = ssh_gssapi_sign(gssctxt, &gssbuf, &mic);
1.133 djm 871:
1.132 markus 872: if (!GSS_ERROR(status)) {
1.278 markus 873: if ((r = sshpkt_start(ssh,
874: SSH2_MSG_USERAUTH_GSSAPI_MIC)) != 0 ||
875: (r = sshpkt_put_string(ssh, mic.value,
876: mic.length)) != 0 ||
877: (r = sshpkt_send(ssh)) != 0)
1.331 djm 878: fatal_fr(r, "send MIC");
1.132 markus 879: }
1.133 djm 880:
1.278 markus 881: sshbuf_free(b);
1.132 markus 882: gss_release_buffer(&ms, &mic);
1.133 djm 883: }
1.130 markus 884: }
1.133 djm 885:
1.130 markus 886: return status;
887: }
888:
1.169 djm 889: /* ARGSUSED */
1.302 djm 890: static int
1.261 markus 891: input_gssapi_response(int type, u_int32_t plen, struct ssh *ssh)
1.121 markus 892: {
1.260 markus 893: Authctxt *authctxt = ssh->authctxt;
1.121 markus 894: Gssctxt *gssctxt;
1.278 markus 895: size_t oidlen;
896: u_char *oidv = NULL;
897: int r;
1.121 markus 898:
899: if (authctxt == NULL)
900: fatal("input_gssapi_response: no authentication context");
901: gssctxt = authctxt->methoddata;
902:
903: /* Setup our OID */
1.278 markus 904: if ((r = sshpkt_get_string(ssh, &oidv, &oidlen)) != 0)
905: goto done;
1.121 markus 906:
1.129 markus 907: if (oidlen <= 2 ||
908: oidv[0] != SSH_GSS_OIDTYPE ||
909: oidv[1] != oidlen - 2) {
910: debug("Badly encoded mechanism OID received");
1.296 djm 911: userauth(ssh, NULL);
1.278 markus 912: goto ok;
1.121 markus 913: }
1.129 markus 914:
915: if (!ssh_gssapi_check_oid(gssctxt, oidv + 2, oidlen - 2))
916: fatal("Server returned different OID than expected");
1.121 markus 917:
1.278 markus 918: if ((r = sshpkt_get_end(ssh)) != 0)
919: goto done;
1.121 markus 920:
1.262 djm 921: if (GSS_ERROR(process_gssapi_token(ssh, GSS_C_NO_BUFFER))) {
1.121 markus 922: /* Start again with next method on list */
923: debug("Trying to start again");
1.296 djm 924: userauth(ssh, NULL);
1.278 markus 925: goto ok;
1.121 markus 926: }
1.278 markus 927: ok:
928: r = 0;
929: done:
930: free(oidv);
931: return r;
1.121 markus 932: }
933:
1.169 djm 934: /* ARGSUSED */
1.302 djm 935: static int
1.261 markus 936: input_gssapi_token(int type, u_int32_t plen, struct ssh *ssh)
1.121 markus 937: {
1.260 markus 938: Authctxt *authctxt = ssh->authctxt;
1.121 markus 939: gss_buffer_desc recv_tok;
1.278 markus 940: u_char *p = NULL;
941: size_t len;
1.130 markus 942: OM_uint32 status;
1.278 markus 943: int r;
1.121 markus 944:
945: if (authctxt == NULL)
946: fatal("input_gssapi_response: no authentication context");
947:
1.278 markus 948: if ((r = sshpkt_get_string(ssh, &p, &len)) != 0 ||
949: (r = sshpkt_get_end(ssh)) != 0)
950: goto out;
1.121 markus 951:
1.278 markus 952: recv_tok.value = p;
953: recv_tok.length = len;
1.262 djm 954: status = process_gssapi_token(ssh, &recv_tok);
1.121 markus 955:
1.278 markus 956: /* Start again with the next method in the list */
1.121 markus 957: if (GSS_ERROR(status)) {
1.296 djm 958: userauth(ssh, NULL);
1.278 markus 959: /* ok */
1.121 markus 960: }
1.278 markus 961: r = 0;
962: out:
963: free(p);
964: return r;
1.121 markus 965: }
966:
1.169 djm 967: /* ARGSUSED */
1.302 djm 968: static int
1.261 markus 969: input_gssapi_errtok(int type, u_int32_t plen, struct ssh *ssh)
1.121 markus 970: {
1.260 markus 971: Authctxt *authctxt = ssh->authctxt;
1.121 markus 972: Gssctxt *gssctxt;
973: gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
974: gss_buffer_desc recv_tok;
1.194 djm 975: OM_uint32 ms;
1.278 markus 976: u_char *p = NULL;
977: size_t len;
978: int r;
1.121 markus 979:
980: if (authctxt == NULL)
981: fatal("input_gssapi_response: no authentication context");
982: gssctxt = authctxt->methoddata;
983:
1.278 markus 984: if ((r = sshpkt_get_string(ssh, &p, &len)) != 0 ||
985: (r = sshpkt_get_end(ssh)) != 0) {
986: free(p);
987: return r;
988: }
1.121 markus 989:
990: /* Stick it into GSSAPI and see what it says */
1.278 markus 991: recv_tok.value = p;
992: recv_tok.length = len;
1.194 djm 993: (void)ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
1.140 djm 994: &recv_tok, &send_tok, NULL);
1.278 markus 995: free(p);
1.121 markus 996: gss_release_buffer(&ms, &send_tok);
997:
998: /* Server will be returning a failed packet after this one */
1.220 djm 999: return 0;
1.121 markus 1000: }
1001:
1.169 djm 1002: /* ARGSUSED */
1.302 djm 1003: static int
1.261 markus 1004: input_gssapi_error(int type, u_int32_t plen, struct ssh *ssh)
1.121 markus 1005: {
1.278 markus 1006: char *msg = NULL;
1007: char *lang = NULL;
1008: int r;
1.121 markus 1009:
1.278 markus 1010: if ((r = sshpkt_get_u32(ssh, NULL)) != 0 || /* maj */
1011: (r = sshpkt_get_u32(ssh, NULL)) != 0 || /* min */
1012: (r = sshpkt_get_cstring(ssh, &msg, NULL)) != 0 ||
1013: (r = sshpkt_get_cstring(ssh, &lang, NULL)) != 0)
1014: goto out;
1015: r = sshpkt_get_end(ssh);
1.143 stevesk 1016: debug("Server GSSAPI Error:\n%s", msg);
1.278 markus 1017: out:
1.197 djm 1018: free(msg);
1019: free(lang);
1.278 markus 1020: return r;
1.121 markus 1021: }
1022: #endif /* GSSAPI */
1.20 markus 1023:
1.302 djm 1024: static int
1.295 djm 1025: userauth_none(struct ssh *ssh)
1.23 markus 1026: {
1.295 djm 1027: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.278 markus 1028: int r;
1029:
1.23 markus 1030: /* initial userauth request */
1.278 markus 1031: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1032: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1033: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1034: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1035: (r = sshpkt_send(ssh)) != 0)
1.331 djm 1036: fatal_fr(r, "send packet");
1.23 markus 1037: return 1;
1038: }
1039:
1.302 djm 1040: static int
1.295 djm 1041: userauth_passwd(struct ssh *ssh)
1.1 markus 1042: {
1.295 djm 1043: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.290 djm 1044: char *password, *prompt = NULL;
1.175 dtucker 1045: const char *host = options.host_key_alias ? options.host_key_alias :
1046: authctxt->host;
1.278 markus 1047: int r;
1.6 markus 1048:
1.292 djm 1049: if (authctxt->attempt_passwd++ >= options.number_of_password_prompts)
1.6 markus 1050: return 0;
1.13 todd 1051:
1.292 djm 1052: if (authctxt->attempt_passwd != 1)
1.13 todd 1053: error("Permission denied, please try again.");
1.1 markus 1054:
1.290 djm 1055: xasprintf(&prompt, "%s@%s's password: ", authctxt->server_user, host);
1.1 markus 1056: password = read_passphrase(prompt, 0);
1.278 markus 1057: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1058: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1059: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1060: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1061: (r = sshpkt_put_u8(ssh, 0)) != 0 ||
1062: (r = sshpkt_put_cstring(ssh, password)) != 0 ||
1063: (r = sshpkt_add_padding(ssh, 64)) != 0 ||
1064: (r = sshpkt_send(ssh)) != 0)
1.331 djm 1065: fatal_fr(r, "send packet");
1.99 markus 1066:
1.290 djm 1067: free(prompt);
1068: if (password != NULL)
1.278 markus 1069: freezero(password, strlen(password));
1070:
1071: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
1.99 markus 1072: &input_userauth_passwd_changereq);
1073:
1.1 markus 1074: return 1;
1075: }
1.169 djm 1076:
1.99 markus 1077: /*
1078: * parse PASSWD_CHANGEREQ, prompt user and send SSH2_MSG_USERAUTH_REQUEST
1079: */
1.169 djm 1080: /* ARGSUSED */
1.302 djm 1081: static int
1.261 markus 1082: input_userauth_passwd_changereq(int type, u_int32_t seqnr, struct ssh *ssh)
1.99 markus 1083: {
1.260 markus 1084: Authctxt *authctxt = ssh->authctxt;
1.278 markus 1085: char *info = NULL, *lang = NULL, *password = NULL, *retype = NULL;
1.266 dtucker 1086: char prompt[256];
1.252 djm 1087: const char *host;
1.278 markus 1088: int r;
1.99 markus 1089:
1090: debug2("input_userauth_passwd_changereq");
1091:
1092: if (authctxt == NULL)
1093: fatal("input_userauth_passwd_changereq: "
1094: "no authentication context");
1.252 djm 1095: host = options.host_key_alias ? options.host_key_alias : authctxt->host;
1.99 markus 1096:
1.278 markus 1097: if ((r = sshpkt_get_cstring(ssh, &info, NULL)) != 0 ||
1098: (r = sshpkt_get_cstring(ssh, &lang, NULL)) != 0)
1099: goto out;
1.99 markus 1100: if (strlen(info) > 0)
1.116 itojun 1101: logit("%s", info);
1.278 markus 1102: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1103: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1104: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1105: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1106: (r = sshpkt_put_u8(ssh, 1)) != 0) /* additional info */
1107: goto out;
1108:
1.104 deraadt 1109: snprintf(prompt, sizeof(prompt),
1.99 markus 1110: "Enter %.30s@%.128s's old password: ",
1.175 dtucker 1111: authctxt->server_user, host);
1.99 markus 1112: password = read_passphrase(prompt, 0);
1.278 markus 1113: if ((r = sshpkt_put_cstring(ssh, password)) != 0)
1114: goto out;
1115:
1116: freezero(password, strlen(password));
1.99 markus 1117: password = NULL;
1118: while (password == NULL) {
1.104 deraadt 1119: snprintf(prompt, sizeof(prompt),
1.99 markus 1120: "Enter %.30s@%.128s's new password: ",
1.175 dtucker 1121: authctxt->server_user, host);
1.99 markus 1122: password = read_passphrase(prompt, RP_ALLOW_EOF);
1123: if (password == NULL) {
1124: /* bail out */
1.278 markus 1125: r = 0;
1126: goto out;
1.99 markus 1127: }
1.104 deraadt 1128: snprintf(prompt, sizeof(prompt),
1.99 markus 1129: "Retype %.30s@%.128s's new password: ",
1.175 dtucker 1130: authctxt->server_user, host);
1.99 markus 1131: retype = read_passphrase(prompt, 0);
1132: if (strcmp(password, retype) != 0) {
1.278 markus 1133: freezero(password, strlen(password));
1.116 itojun 1134: logit("Mismatch; try again, EOF to quit.");
1.99 markus 1135: password = NULL;
1136: }
1.278 markus 1137: freezero(retype, strlen(retype));
1.99 markus 1138: }
1.278 markus 1139: if ((r = sshpkt_put_cstring(ssh, password)) != 0 ||
1140: (r = sshpkt_add_padding(ssh, 64)) != 0 ||
1141: (r = sshpkt_send(ssh)) != 0)
1142: goto out;
1.104 deraadt 1143:
1.278 markus 1144: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
1.99 markus 1145: &input_userauth_passwd_changereq);
1.278 markus 1146: r = 0;
1147: out:
1148: if (password)
1149: freezero(password, strlen(password));
1150: free(info);
1151: free(lang);
1152: return r;
1.117 markus 1153: }
1154:
1.272 djm 1155: /*
1156: * Select an algorithm for publickey signatures.
1157: * Returns algorithm (caller must free) or NULL if no mutual algorithm found.
1158: *
1159: * Call with ssh==NULL to ignore server-sig-algs extension list and
1160: * only attempt with the key's base signature type.
1161: */
1162: static char *
1163: key_sig_algorithm(struct ssh *ssh, const struct sshkey *key)
1.231 markus 1164: {
1.274 djm 1165: char *allowed, *oallowed, *cp, *tmp, *alg = NULL;
1.231 markus 1166:
1.272 djm 1167: /*
1168: * The signature algorithm will only differ from the key algorithm
1169: * for RSA keys/certs and when the server advertises support for
1170: * newer (SHA2) algorithms.
1171: */
1172: if (ssh == NULL || ssh->kex->server_sig_algs == NULL ||
1.288 djm 1173: (key->type != KEY_RSA && key->type != KEY_RSA_CERT) ||
1174: (key->type == KEY_RSA_CERT && (datafellows & SSH_BUG_SIGTYPE))) {
1.272 djm 1175: /* Filter base key signature alg against our configuration */
1.279 markus 1176: return match_list(sshkey_ssh_name(key),
1.272 djm 1177: options.pubkey_key_types, NULL);
1.231 markus 1178: }
1179:
1.272 djm 1180: /*
1181: * For RSA keys/certs, since these might have a different sig type:
1182: * find the first entry in PubkeyAcceptedKeyTypes of the right type
1183: * that also appears in the supported signature algorithms list from
1184: * the server.
1185: */
1186: oallowed = allowed = xstrdup(options.pubkey_key_types);
1187: while ((cp = strsep(&allowed, ",")) != NULL) {
1188: if (sshkey_type_from_name(cp) != key->type)
1189: continue;
1.323 djm 1190: tmp = match_list(sshkey_sigalg_by_name(cp),
1191: ssh->kex->server_sig_algs, NULL);
1.274 djm 1192: if (tmp != NULL)
1193: alg = xstrdup(cp);
1194: free(tmp);
1.272 djm 1195: if (alg != NULL)
1196: break;
1.269 djm 1197: }
1.272 djm 1198: free(oallowed);
1199: return alg;
1.269 djm 1200: }
1201:
1.117 markus 1202: static int
1.214 djm 1203: identity_sign(struct identity *id, u_char **sigp, size_t *lenp,
1.272 djm 1204: const u_char *data, size_t datalen, u_int compat, const char *alg)
1.117 markus 1205: {
1.309 djm 1206: struct sshkey *sign_key = NULL, *prv = NULL;
1207: int r = SSH_ERR_INTERNAL_ERROR;
1.312 djm 1208: struct notifier_ctx *notifier = NULL;
1.325 djm 1209: char *fp = NULL, *pin = NULL, *prompt = NULL;
1.309 djm 1210:
1211: *sigp = NULL;
1212: *lenp = 0;
1.99 markus 1213:
1.272 djm 1214: /* The agent supports this key. */
1.269 djm 1215: if (id->key != NULL && id->agent_fd != -1) {
1.272 djm 1216: return ssh_agent_sign(id->agent_fd, id->key, sigp, lenp,
1217: data, datalen, alg, compat);
1.269 djm 1218: }
1.214 djm 1219:
1.117 markus 1220: /*
1.272 djm 1221: * We have already loaded the private key or the private key is
1222: * stored in external hardware.
1.117 markus 1223: */
1.255 djm 1224: if (id->key != NULL &&
1.272 djm 1225: (id->isprivate || (id->key->flags & SSHKEY_FLAG_EXT))) {
1.309 djm 1226: sign_key = id->key;
1227: } else {
1228: /* Load the private key from the file. */
1229: if ((prv = load_identity_file(id)) == NULL)
1230: return SSH_ERR_KEY_NOT_FOUND;
1231: if (id->key != NULL && !sshkey_equal_public(prv, id->key)) {
1.331 djm 1232: error_f("private key %s contents do not match public",
1233: id->filename);
1.309 djm 1234: r = SSH_ERR_KEY_NOT_FOUND;
1235: goto out;
1236: }
1237: sign_key = prv;
1.325 djm 1238: if (sshkey_is_sk(sign_key)) {
1239: if ((sign_key->sk_flags &
1240: SSH_SK_USER_VERIFICATION_REQD)) {
1241: xasprintf(&prompt, "Enter PIN for %s key %s: ",
1242: sshkey_type(sign_key), id->filename);
1243: pin = read_passphrase(prompt, 0);
1244: }
1245: if ((sign_key->sk_flags & SSH_SK_USER_PRESENCE_REQD)) {
1246: /* XXX should batch mode just skip these? */
1247: if ((fp = sshkey_fingerprint(sign_key,
1248: options.fingerprint_hash,
1249: SSH_FP_DEFAULT)) == NULL)
1.331 djm 1250: fatal_f("fingerprint failed");
1.325 djm 1251: notifier = notify_start(options.batch_mode,
1252: "Confirm user presence for key %s %s",
1253: sshkey_type(sign_key), fp);
1254: free(fp);
1255: }
1.312 djm 1256: }
1.272 djm 1257: }
1.310 djm 1258: if ((r = sshkey_sign(sign_key, sigp, lenp, data, datalen,
1.325 djm 1259: alg, options.sk_provider, pin, compat)) != 0) {
1.331 djm 1260: debug_fr(r, "sshkey_sign");
1.309 djm 1261: goto out;
1262: }
1263: /*
1264: * PKCS#11 tokens may not support all signature algorithms,
1265: * so check what we get back.
1266: */
1267: if ((r = sshkey_check_sigtype(*sigp, *lenp, alg)) != 0) {
1.331 djm 1268: debug_fr(r, "sshkey_check_sigtype");
1.309 djm 1269: goto out;
1.265 djm 1270: }
1.309 djm 1271: /* success */
1272: r = 0;
1273: out:
1.325 djm 1274: free(prompt);
1275: if (pin != NULL)
1276: freezero(pin, strlen(pin));
1.334 djm 1277: notify_complete(notifier, "User presence confirmed");
1.214 djm 1278: sshkey_free(prv);
1.269 djm 1279: return r;
1.51 markus 1280: }
1281:
1.76 itojun 1282: static int
1.255 djm 1283: id_filename_matches(Identity *id, Identity *private_id)
1284: {
1285: const char *suffixes[] = { ".pub", "-cert.pub", NULL };
1286: size_t len = strlen(id->filename), plen = strlen(private_id->filename);
1287: size_t i, slen;
1288:
1289: if (strcmp(id->filename, private_id->filename) == 0)
1290: return 1;
1291: for (i = 0; suffixes[i]; i++) {
1292: slen = strlen(suffixes[i]);
1293: if (len > slen && plen == len - slen &&
1294: strcmp(id->filename + (len - slen), suffixes[i]) == 0 &&
1295: memcmp(id->filename, private_id->filename, plen) == 0)
1296: return 1;
1297: }
1298: return 0;
1299: }
1300:
1301: static int
1.295 djm 1302: sign_and_send_pubkey(struct ssh *ssh, Identity *id)
1.1 markus 1303: {
1.295 djm 1304: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.272 djm 1305: struct sshbuf *b = NULL;
1306: Identity *private_id, *sign_id = NULL;
1307: u_char *signature = NULL;
1308: size_t slen = 0, skip = 0;
1309: int r, fallback_sigtype, sent = 0;
1310: char *alg = NULL, *fp = NULL;
1311: const char *loc = "";
1.1 markus 1312:
1.222 djm 1313: if ((fp = sshkey_fingerprint(id->key, options.fingerprint_hash,
1314: SSH_FP_DEFAULT)) == NULL)
1315: return 0;
1.51 markus 1316:
1.331 djm 1317: debug3_f("%s %s", sshkey_type(id->key), fp);
1.1 markus 1318:
1.227 djm 1319: /*
1320: * If the key is an certificate, try to find a matching private key
1321: * and use it to complete the signature.
1.241 djm 1322: * If no such private key exists, fall back to trying the certificate
1323: * key itself in case it has a private half already loaded.
1.272 djm 1324: * This will try to set sign_id to the private key that will perform
1325: * the signature.
1.227 djm 1326: */
1.272 djm 1327: if (sshkey_is_cert(id->key)) {
1.227 djm 1328: TAILQ_FOREACH(private_id, &authctxt->keys, next) {
1329: if (sshkey_equal_public(id->key, private_id->key) &&
1330: id->key->type != private_id->key->type) {
1.272 djm 1331: sign_id = private_id;
1.227 djm 1332: break;
1333: }
1334: }
1.255 djm 1335: /*
1336: * Exact key matches are preferred, but also allow
1337: * filename matches for non-PKCS#11/agent keys that
1338: * didn't load public keys. This supports the case
1339: * of keeping just a private key file and public
1340: * certificate on disk.
1341: */
1.272 djm 1342: if (sign_id == NULL &&
1343: !id->isprivate && id->agent_fd == -1 &&
1.255 djm 1344: (id->key->flags & SSHKEY_FLAG_EXT) == 0) {
1345: TAILQ_FOREACH(private_id, &authctxt->keys, next) {
1346: if (private_id->key == NULL &&
1347: id_filename_matches(id, private_id)) {
1.272 djm 1348: sign_id = private_id;
1.255 djm 1349: break;
1350: }
1351: }
1352: }
1.272 djm 1353: if (sign_id != NULL) {
1.331 djm 1354: debug2_f("using private key \"%s\"%s for "
1355: "certificate", id->filename,
1.227 djm 1356: id->agent_fd != -1 ? " from agent" : "");
1357: } else {
1.331 djm 1358: debug_f("no separate private key for certificate "
1359: "\"%s\"", id->filename);
1.227 djm 1360: }
1361: }
1362:
1.272 djm 1363: /*
1364: * If the above didn't select another identity to do the signing
1365: * then default to the one we started with.
1366: */
1367: if (sign_id == NULL)
1368: sign_id = id;
1369:
1370: /* assemble and sign data */
1371: for (fallback_sigtype = 0; fallback_sigtype <= 1; fallback_sigtype++) {
1372: free(alg);
1373: slen = 0;
1374: signature = NULL;
1375: if ((alg = key_sig_algorithm(fallback_sigtype ? NULL : ssh,
1376: id->key)) == NULL) {
1.331 djm 1377: error_f("no mutual signature supported");
1.272 djm 1378: goto out;
1379: }
1.331 djm 1380: debug3_f("signing using %s %s", alg, fp);
1.272 djm 1381:
1382: sshbuf_free(b);
1383: if ((b = sshbuf_new()) == NULL)
1.331 djm 1384: fatal_f("sshbuf_new failed");
1.272 djm 1385: if (datafellows & SSH_OLD_SESSIONID) {
1386: if ((r = sshbuf_put(b, session_id2,
1.331 djm 1387: session_id2_len)) != 0)
1388: fatal_fr(r, "sshbuf_put");
1.272 djm 1389: } else {
1390: if ((r = sshbuf_put_string(b, session_id2,
1.331 djm 1391: session_id2_len)) != 0)
1392: fatal_fr(r, "sshbuf_put_string");
1.272 djm 1393: }
1.278 markus 1394: skip = sshbuf_len(b);
1.272 djm 1395: if ((r = sshbuf_put_u8(b, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1396: (r = sshbuf_put_cstring(b, authctxt->server_user)) != 0 ||
1397: (r = sshbuf_put_cstring(b, authctxt->service)) != 0 ||
1398: (r = sshbuf_put_cstring(b, authctxt->method->name)) != 0 ||
1399: (r = sshbuf_put_u8(b, 1)) != 0 ||
1400: (r = sshbuf_put_cstring(b, alg)) != 0 ||
1401: (r = sshkey_puts(id->key, b)) != 0) {
1.331 djm 1402: fatal_fr(r, "assemble signed data");
1.272 djm 1403: }
1404:
1405: /* generate signature */
1406: r = identity_sign(sign_id, &signature, &slen,
1407: sshbuf_ptr(b), sshbuf_len(b), datafellows, alg);
1408: if (r == 0)
1409: break;
1410: else if (r == SSH_ERR_KEY_NOT_FOUND)
1411: goto out; /* soft failure */
1412: else if (r == SSH_ERR_SIGN_ALG_UNSUPPORTED &&
1413: !fallback_sigtype) {
1414: if (sign_id->agent_fd != -1)
1415: loc = "agent ";
1416: else if ((sign_id->key->flags & SSHKEY_FLAG_EXT) != 0)
1417: loc = "token ";
1418: logit("%skey %s %s returned incorrect signature type",
1419: loc, sshkey_type(id->key), fp);
1420: continue;
1421: }
1.331 djm 1422: error_fr(r, "signing failed for %s \"%s\"%s",
1.315 djm 1423: sshkey_type(sign_id->key), sign_id->filename,
1.331 djm 1424: id->agent_fd != -1 ? " from agent" : "");
1.272 djm 1425: goto out;
1.17 markus 1426: }
1.272 djm 1427: if (slen == 0 || signature == NULL) /* shouldn't happen */
1.331 djm 1428: fatal_f("no signature");
1.51 markus 1429:
1.1 markus 1430: /* append signature */
1.272 djm 1431: if ((r = sshbuf_put_string(b, signature, slen)) != 0)
1.331 djm 1432: fatal_fr(r, "append signature");
1.1 markus 1433:
1.272 djm 1434: #ifdef DEBUG_PK
1435: sshbuf_dump(b, stderr);
1436: #endif
1.1 markus 1437: /* skip session id and packet type */
1.272 djm 1438: if ((r = sshbuf_consume(b, skip + 1)) != 0)
1.331 djm 1439: fatal_fr(r, "consume");
1.1 markus 1440:
1441: /* put remaining data from buffer into packet */
1.272 djm 1442: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1443: (r = sshpkt_putb(ssh, b)) != 0 ||
1444: (r = sshpkt_send(ssh)) != 0)
1.331 djm 1445: fatal_fr(r, "enqueue request");
1.272 djm 1446:
1447: /* success */
1448: sent = 1;
1.17 markus 1449:
1.272 djm 1450: out:
1451: free(fp);
1452: free(alg);
1453: sshbuf_free(b);
1454: freezero(signature, slen);
1455: return sent;
1.16 markus 1456: }
1457:
1.76 itojun 1458: static int
1.295 djm 1459: send_pubkey_test(struct ssh *ssh, Identity *id)
1.20 markus 1460: {
1.295 djm 1461: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.272 djm 1462: u_char *blob = NULL;
1463: char *alg = NULL;
1.278 markus 1464: size_t bloblen;
1465: u_int have_sig = 0;
1466: int sent = 0, r;
1.20 markus 1467:
1.272 djm 1468: if ((alg = key_sig_algorithm(ssh, id->key)) == NULL) {
1.331 djm 1469: debug_f("no mutual signature algorithm");
1.272 djm 1470: goto out;
1471: }
1.16 markus 1472:
1.278 markus 1473: if ((r = sshkey_to_blob(id->key, &blob, &bloblen)) != 0) {
1.51 markus 1474: /* we cannot handle this key */
1.331 djm 1475: debug3_f("cannot handle key");
1.272 djm 1476: goto out;
1.16 markus 1477: }
1.51 markus 1478: /* register callback for USERAUTH_PK_OK message */
1.278 markus 1479: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_PK_OK, &input_userauth_pk_ok);
1.51 markus 1480:
1.278 markus 1481: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1482: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1483: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1484: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1485: (r = sshpkt_put_u8(ssh, have_sig)) != 0 ||
1486: (r = sshpkt_put_cstring(ssh, alg)) != 0 ||
1487: (r = sshpkt_put_string(ssh, blob, bloblen)) != 0 ||
1488: (r = sshpkt_send(ssh)) != 0)
1.331 djm 1489: fatal_fr(r, "send packet");
1.272 djm 1490: sent = 1;
1.278 markus 1491:
1492: out:
1.272 djm 1493: free(alg);
1.197 djm 1494: free(blob);
1.272 djm 1495: return sent;
1.51 markus 1496: }
1497:
1.259 markus 1498: static struct sshkey *
1.229 jcs 1499: load_identity_file(Identity *id)
1.51 markus 1500: {
1.259 markus 1501: struct sshkey *private = NULL;
1.229 jcs 1502: char prompt[300], *passphrase, *comment;
1.308 dtucker 1503: int r, quit = 0, i;
1.52 markus 1504: struct stat st;
1.16 markus 1505:
1.306 deraadt 1506: if (stat(id->filename, &st) == -1) {
1.330 djm 1507: do_log2(id->userprovided ?
1508: SYSLOG_LEVEL_INFO : SYSLOG_LEVEL_DEBUG3,
1509: "no such identity: %s: %s", id->filename, strerror(errno));
1.52 markus 1510: return NULL;
1511: }
1.214 djm 1512: snprintf(prompt, sizeof prompt,
1.229 jcs 1513: "Enter passphrase for key '%.100s': ", id->filename);
1.214 djm 1514: for (i = 0; i <= options.number_of_password_prompts; i++) {
1515: if (i == 0)
1516: passphrase = "";
1517: else {
1.20 markus 1518: passphrase = read_passphrase(prompt, 0);
1.214 djm 1519: if (*passphrase == '\0') {
1.20 markus 1520: debug2("no passphrase given, try next key");
1.214 djm 1521: free(passphrase);
1522: break;
1523: }
1524: }
1.229 jcs 1525: switch ((r = sshkey_load_private_type(KEY_UNSPEC, id->filename,
1.308 dtucker 1526: passphrase, &private, &comment))) {
1.214 djm 1527: case 0:
1528: break;
1529: case SSH_ERR_KEY_WRONG_PASSPHRASE:
1530: if (options.batch_mode) {
1531: quit = 1;
1532: break;
1533: }
1.215 djm 1534: if (i != 0)
1535: debug2("bad passphrase given, try again...");
1.214 djm 1536: break;
1537: case SSH_ERR_SYSTEM_ERROR:
1538: if (errno == ENOENT) {
1.331 djm 1539: debug2_r(r, "Load key \"%s\"", id->filename);
1.51 markus 1540: quit = 1;
1.214 djm 1541: break;
1.20 markus 1542: }
1.214 djm 1543: /* FALLTHROUGH */
1544: default:
1.331 djm 1545: error_r(r, "Load key \"%s\"", id->filename);
1.214 djm 1546: quit = 1;
1547: break;
1548: }
1.311 markus 1549: if (private != NULL && sshkey_is_sk(private) &&
1.309 djm 1550: options.sk_provider == NULL) {
1.319 naddy 1551: debug("key \"%s\" is an authenticator-hosted key, "
1552: "but no provider specified", id->filename);
1.309 djm 1553: sshkey_free(private);
1554: private = NULL;
1555: quit = 1;
1556: }
1.230 djm 1557: if (!quit && private != NULL && id->agent_fd == -1 &&
1.229 jcs 1558: !(id->key && id->isprivate))
1559: maybe_add_key_to_agent(id->filename, private, comment,
1560: passphrase);
1.278 markus 1561: if (i > 0)
1562: freezero(passphrase, strlen(passphrase));
1.232 mmcc 1563: free(comment);
1.214 djm 1564: if (private != NULL || quit)
1565: break;
1.16 markus 1566: }
1.51 markus 1567: return private;
1568: }
1569:
1.272 djm 1570: static int
1571: key_type_allowed_by_config(struct sshkey *key)
1572: {
1573: if (match_pattern_list(sshkey_ssh_name(key),
1574: options.pubkey_key_types, 0) == 1)
1575: return 1;
1576:
1577: /* RSA keys/certs might be allowed by alternate signature types */
1578: switch (key->type) {
1579: case KEY_RSA:
1580: if (match_pattern_list("rsa-sha2-512",
1581: options.pubkey_key_types, 0) == 1)
1582: return 1;
1583: if (match_pattern_list("rsa-sha2-256",
1584: options.pubkey_key_types, 0) == 1)
1585: return 1;
1586: break;
1587: case KEY_RSA_CERT:
1588: if (match_pattern_list("rsa-sha2-512-cert-v01@openssh.com",
1589: options.pubkey_key_types, 0) == 1)
1590: return 1;
1591: if (match_pattern_list("rsa-sha2-256-cert-v01@openssh.com",
1592: options.pubkey_key_types, 0) == 1)
1593: return 1;
1594: break;
1595: }
1596: return 0;
1597: }
1598:
1599:
1.117 markus 1600: /*
1601: * try keys in the following order:
1.332 djm 1602: * 1. certificates listed in the config file
1603: * 2. other input certificates
1.227 djm 1604: * 3. agent keys that are found in the config file
1605: * 4. other agent keys
1606: * 5. keys that are only listed in the config file
1.117 markus 1607: */
1608: static void
1609: pubkey_prepare(Authctxt *authctxt)
1.51 markus 1610: {
1.214 djm 1611: struct identity *id, *id2, *tmp;
1612: struct idlist agent, files, *preferred;
1613: struct sshkey *key;
1.230 djm 1614: int agent_fd = -1, i, r, found;
1.214 djm 1615: size_t j;
1616: struct ssh_identitylist *idlist;
1.287 djm 1617: char *ident;
1.51 markus 1618:
1.117 markus 1619: TAILQ_INIT(&agent); /* keys from the agent */
1620: TAILQ_INIT(&files); /* keys from the config file */
1621: preferred = &authctxt->keys;
1622: TAILQ_INIT(preferred); /* preferred order of keys */
1623:
1.190 djm 1624: /* list of keys stored in the filesystem and PKCS#11 */
1.117 markus 1625: for (i = 0; i < options.num_identity_files; i++) {
1626: key = options.identity_keys[i];
1.309 djm 1627: if (key && key->cert &&
1628: key->cert->type != SSH2_CERT_TYPE_USER) {
1.331 djm 1629: debug_f("ignoring certificate %s: not a user "
1630: "certificate", options.identity_files[i]);
1.309 djm 1631: continue;
1632: }
1.311 markus 1633: if (key && sshkey_is_sk(key) && options.sk_provider == NULL) {
1.331 djm 1634: debug_f("ignoring authenticator-hosted key %s as no "
1.309 djm 1635: "SecurityKeyProvider has been specified",
1.331 djm 1636: options.identity_files[i]);
1.117 markus 1637: continue;
1.309 djm 1638: }
1.117 markus 1639: options.identity_keys[i] = NULL;
1.150 djm 1640: id = xcalloc(1, sizeof(*id));
1.230 djm 1641: id->agent_fd = -1;
1.117 markus 1642: id->key = key;
1643: id->filename = xstrdup(options.identity_files[i]);
1.192 dtucker 1644: id->userprovided = options.identity_file_userprovided[i];
1.117 markus 1645: TAILQ_INSERT_TAIL(&files, id, next);
1.190 djm 1646: }
1.227 djm 1647: /* list of certificates specified by user */
1648: for (i = 0; i < options.num_certificate_files; i++) {
1649: key = options.certificates[i];
1.278 markus 1650: if (!sshkey_is_cert(key) || key->cert == NULL ||
1.309 djm 1651: key->cert->type != SSH2_CERT_TYPE_USER) {
1.331 djm 1652: debug_f("ignoring certificate %s: not a user "
1653: "certificate", options.identity_files[i]);
1.227 djm 1654: continue;
1.309 djm 1655: }
1.311 markus 1656: if (key && sshkey_is_sk(key) && options.sk_provider == NULL) {
1.331 djm 1657: debug_f("ignoring authenticator-hosted key "
1.319 naddy 1658: "certificate %s as no "
1.309 djm 1659: "SecurityKeyProvider has been specified",
1.331 djm 1660: options.identity_files[i]);
1.309 djm 1661: continue;
1662: }
1.227 djm 1663: id = xcalloc(1, sizeof(*id));
1.230 djm 1664: id->agent_fd = -1;
1.227 djm 1665: id->key = key;
1666: id->filename = xstrdup(options.certificate_files[i]);
1667: id->userprovided = options.certificate_file_userprovided[i];
1668: TAILQ_INSERT_TAIL(preferred, id, next);
1.117 markus 1669: }
1670: /* list of keys supported by the agent */
1.214 djm 1671: if ((r = ssh_get_authentication_socket(&agent_fd)) != 0) {
1672: if (r != SSH_ERR_AGENT_NOT_PRESENT)
1.331 djm 1673: debug_fr(r, "ssh_get_authentication_socket");
1.258 naddy 1674: } else if ((r = ssh_fetch_identitylist(agent_fd, &idlist)) != 0) {
1.214 djm 1675: if (r != SSH_ERR_AGENT_NO_IDENTITIES)
1.331 djm 1676: debug_fr(r, "ssh_fetch_identitylist");
1.237 markus 1677: close(agent_fd);
1.214 djm 1678: } else {
1679: for (j = 0; j < idlist->nkeys; j++) {
1.117 markus 1680: found = 0;
1681: TAILQ_FOREACH(id, &files, next) {
1.214 djm 1682: /*
1683: * agent keys from the config file are
1684: * preferred
1685: */
1686: if (sshkey_equal(idlist->keys[j], id->key)) {
1.117 markus 1687: TAILQ_REMOVE(&files, id, next);
1688: TAILQ_INSERT_TAIL(preferred, id, next);
1.214 djm 1689: id->agent_fd = agent_fd;
1.117 markus 1690: found = 1;
1691: break;
1692: }
1693: }
1.135 markus 1694: if (!found && !options.identities_only) {
1.150 djm 1695: id = xcalloc(1, sizeof(*id));
1.214 djm 1696: /* XXX "steals" key/comment from idlist */
1697: id->key = idlist->keys[j];
1698: id->filename = idlist->comments[j];
1699: idlist->keys[j] = NULL;
1700: idlist->comments[j] = NULL;
1701: id->agent_fd = agent_fd;
1.117 markus 1702: TAILQ_INSERT_TAIL(&agent, id, next);
1703: }
1704: }
1.214 djm 1705: ssh_free_identitylist(idlist);
1.117 markus 1706: /* append remaining agent keys */
1.324 bket 1707: TAILQ_CONCAT(preferred, &agent, next);
1.214 djm 1708: authctxt->agent_fd = agent_fd;
1.244 djm 1709: }
1710: /* Prefer PKCS11 keys that are explicitly listed */
1711: TAILQ_FOREACH_SAFE(id, &files, next, tmp) {
1712: if (id->key == NULL || (id->key->flags & SSHKEY_FLAG_EXT) == 0)
1713: continue;
1714: found = 0;
1715: TAILQ_FOREACH(id2, &files, next) {
1716: if (id2->key == NULL ||
1.321 djm 1717: (id2->key->flags & SSHKEY_FLAG_EXT) != 0)
1.244 djm 1718: continue;
1719: if (sshkey_equal(id->key, id2->key)) {
1720: TAILQ_REMOVE(&files, id, next);
1721: TAILQ_INSERT_TAIL(preferred, id, next);
1722: found = 1;
1723: break;
1724: }
1725: }
1726: /* If IdentitiesOnly set and key not found then don't use it */
1727: if (!found && options.identities_only) {
1728: TAILQ_REMOVE(&files, id, next);
1.278 markus 1729: freezero(id, sizeof(*id));
1.244 djm 1730: }
1.117 markus 1731: }
1732: /* append remaining keys from the config file */
1.324 bket 1733: TAILQ_CONCAT(preferred, &files, next);
1.228 djm 1734: /* finally, filter by PubkeyAcceptedKeyTypes */
1735: TAILQ_FOREACH_SAFE(id, preferred, next, id2) {
1.273 djm 1736: if (id->key != NULL && !key_type_allowed_by_config(id->key)) {
1.228 djm 1737: debug("Skipping %s key %s - "
1738: "not in PubkeyAcceptedKeyTypes",
1739: sshkey_ssh_name(id->key), id->filename);
1740: TAILQ_REMOVE(preferred, id, next);
1741: sshkey_free(id->key);
1742: free(id->filename);
1743: memset(id, 0, sizeof(*id));
1744: continue;
1745: }
1.117 markus 1746: }
1.287 djm 1747: /* List the keys we plan on using */
1748: TAILQ_FOREACH_SAFE(id, preferred, next, id2) {
1749: ident = format_identity(id);
1750: debug("Will attempt key: %s", ident);
1751: free(ident);
1752: }
1.331 djm 1753: debug2_f("done");
1.17 markus 1754: }
1755:
1.117 markus 1756: static void
1.303 djm 1757: pubkey_cleanup(struct ssh *ssh)
1.51 markus 1758: {
1.302 djm 1759: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.117 markus 1760: Identity *id;
1.51 markus 1761:
1.289 djm 1762: if (authctxt->agent_fd != -1) {
1.214 djm 1763: ssh_close_authentication_socket(authctxt->agent_fd);
1.289 djm 1764: authctxt->agent_fd = -1;
1765: }
1.117 markus 1766: for (id = TAILQ_FIRST(&authctxt->keys); id;
1767: id = TAILQ_FIRST(&authctxt->keys)) {
1768: TAILQ_REMOVE(&authctxt->keys, id, next);
1.235 mmcc 1769: sshkey_free(id->key);
1.197 djm 1770: free(id->filename);
1771: free(id);
1.117 markus 1772: }
1.1 markus 1773: }
1774:
1.251 djm 1775: static void
1776: pubkey_reset(Authctxt *authctxt)
1777: {
1778: Identity *id;
1779:
1780: TAILQ_FOREACH(id, &authctxt->keys, next)
1781: id->tried = 0;
1782: }
1783:
1.225 markus 1784: static int
1785: try_identity(Identity *id)
1786: {
1787: if (!id->key)
1788: return (0);
1.279 markus 1789: if (sshkey_type_plain(id->key->type) == KEY_RSA &&
1.225 markus 1790: (datafellows & SSH_BUG_RSASIGMD5) != 0) {
1791: debug("Skipped %s key %s for RSA/MD5 server",
1.279 markus 1792: sshkey_type(id->key), id->filename);
1.225 markus 1793: return (0);
1794: }
1.257 djm 1795: return 1;
1.225 markus 1796: }
1797:
1.302 djm 1798: static int
1.295 djm 1799: userauth_pubkey(struct ssh *ssh)
1.20 markus 1800: {
1.295 djm 1801: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.117 markus 1802: Identity *id;
1.20 markus 1803: int sent = 0;
1.287 djm 1804: char *ident;
1.20 markus 1805:
1.117 markus 1806: while ((id = TAILQ_FIRST(&authctxt->keys))) {
1807: if (id->tried++)
1808: return (0);
1.127 markus 1809: /* move key to the end of the queue */
1.117 markus 1810: TAILQ_REMOVE(&authctxt->keys, id, next);
1811: TAILQ_INSERT_TAIL(&authctxt->keys, id, next);
1812: /*
1813: * send a test message if we have the public key. for
1814: * encrypted keys we cannot do this and have to load the
1815: * private key instead
1816: */
1.200 djm 1817: if (id->key != NULL) {
1.225 markus 1818: if (try_identity(id)) {
1.287 djm 1819: ident = format_identity(id);
1820: debug("Offering public key: %s", ident);
1821: free(ident);
1.295 djm 1822: sent = send_pubkey_test(ssh, id);
1.200 djm 1823: }
1824: } else {
1.117 markus 1825: debug("Trying private key: %s", id->filename);
1.229 jcs 1826: id->key = load_identity_file(id);
1.117 markus 1827: if (id->key != NULL) {
1.225 markus 1828: if (try_identity(id)) {
1829: id->isprivate = 1;
1.295 djm 1830: sent = sign_and_send_pubkey(ssh, id);
1.200 djm 1831: }
1.278 markus 1832: sshkey_free(id->key);
1.117 markus 1833: id->key = NULL;
1.251 djm 1834: id->isprivate = 0;
1.51 markus 1835: }
1836: }
1.117 markus 1837: if (sent)
1838: return (sent);
1.28 markus 1839: }
1.117 markus 1840: return (0);
1.20 markus 1841: }
1842:
1.23 markus 1843: /*
1844: * Send userauth request message specifying keyboard-interactive method.
1845: */
1.302 djm 1846: static int
1.295 djm 1847: userauth_kbdint(struct ssh *ssh)
1.23 markus 1848: {
1.295 djm 1849: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.278 markus 1850: int r;
1.23 markus 1851:
1.292 djm 1852: if (authctxt->attempt_kbdint++ >= options.number_of_password_prompts)
1.23 markus 1853: return 0;
1.82 markus 1854: /* disable if no SSH2_MSG_USERAUTH_INFO_REQUEST has been seen */
1.292 djm 1855: if (authctxt->attempt_kbdint > 1 && !authctxt->info_req_seen) {
1.82 markus 1856: debug3("userauth_kbdint: disable: no info_req_seen");
1.278 markus 1857: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_INFO_REQUEST, NULL);
1.82 markus 1858: return 0;
1859: }
1.23 markus 1860:
1861: debug2("userauth_kbdint");
1.278 markus 1862: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1863: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1864: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1865: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1866: (r = sshpkt_put_cstring(ssh, "")) != 0 || /* lang */
1867: (r = sshpkt_put_cstring(ssh, options.kbd_interactive_devices ?
1868: options.kbd_interactive_devices : "")) != 0 ||
1869: (r = sshpkt_send(ssh)) != 0)
1.331 djm 1870: fatal_fr(r, "send packet");
1.23 markus 1871:
1.278 markus 1872: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_INFO_REQUEST, &input_userauth_info_req);
1.23 markus 1873: return 1;
1874: }
1875:
1876: /*
1.46 markus 1877: * parse INFO_REQUEST, prompt user and send INFO_RESPONSE
1.23 markus 1878: */
1.302 djm 1879: static int
1.261 markus 1880: input_userauth_info_req(int type, u_int32_t seq, struct ssh *ssh)
1.23 markus 1881: {
1.260 markus 1882: Authctxt *authctxt = ssh->authctxt;
1.278 markus 1883: char *name = NULL, *inst = NULL, *lang = NULL, *prompt = NULL;
1.335 djm 1884: char *display_prompt = NULL, *response = NULL;
1.278 markus 1885: u_char echo = 0;
1.32 markus 1886: u_int num_prompts, i;
1.278 markus 1887: int r;
1.23 markus 1888:
1.335 djm 1889: debug2_f("entering");
1.23 markus 1890:
1891: if (authctxt == NULL)
1.335 djm 1892: fatal_f("no authentication context");
1.82 markus 1893:
1894: authctxt->info_req_seen = 1;
1.23 markus 1895:
1.278 markus 1896: if ((r = sshpkt_get_cstring(ssh, &name, NULL)) != 0 ||
1897: (r = sshpkt_get_cstring(ssh, &inst, NULL)) != 0 ||
1898: (r = sshpkt_get_cstring(ssh, &lang, NULL)) != 0)
1899: goto out;
1.23 markus 1900: if (strlen(name) > 0)
1.116 itojun 1901: logit("%s", name);
1.23 markus 1902: if (strlen(inst) > 0)
1.116 itojun 1903: logit("%s", inst);
1.23 markus 1904:
1.278 markus 1905: if ((r = sshpkt_get_u32(ssh, &num_prompts)) != 0)
1906: goto out;
1.23 markus 1907: /*
1908: * Begin to build info response packet based on prompts requested.
1909: * We commit to providing the correct number of responses, so if
1910: * further on we run into a problem that prevents this, we have to
1911: * be sure and clean this up and send a correct error response.
1912: */
1.278 markus 1913: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_INFO_RESPONSE)) != 0 ||
1914: (r = sshpkt_put_u32(ssh, num_prompts)) != 0)
1915: goto out;
1.23 markus 1916:
1.335 djm 1917: debug2_f("num_prompts %d", num_prompts);
1.23 markus 1918: for (i = 0; i < num_prompts; i++) {
1.278 markus 1919: if ((r = sshpkt_get_cstring(ssh, &prompt, NULL)) != 0 ||
1920: (r = sshpkt_get_u8(ssh, &echo)) != 0)
1921: goto out;
1.336 djm 1922: if (asmprintf(&display_prompt, INT_MAX, NULL, "(%s@%s) %s",
1.335 djm 1923: authctxt->server_user, options.host_key_alias ?
1.336 djm 1924: options.host_key_alias : authctxt->host, prompt) == -1)
1925: fatal_f("asmprintf failed");
1.335 djm 1926: response = read_passphrase(display_prompt, echo ? RP_ECHO : 0);
1.278 markus 1927: if ((r = sshpkt_put_cstring(ssh, response)) != 0)
1928: goto out;
1929: freezero(response, strlen(response));
1.197 djm 1930: free(prompt);
1.335 djm 1931: free(display_prompt);
1932: display_prompt = response = prompt = NULL;
1.23 markus 1933: }
1.278 markus 1934: /* done with parsing incoming message. */
1935: if ((r = sshpkt_get_end(ssh)) != 0 ||
1936: (r = sshpkt_add_padding(ssh, 64)) != 0)
1937: goto out;
1938: r = sshpkt_send(ssh);
1939: out:
1940: if (response)
1941: freezero(response, strlen(response));
1942: free(prompt);
1.335 djm 1943: free(display_prompt);
1.278 markus 1944: free(name);
1945: free(inst);
1946: free(lang);
1947: return r;
1.68 markus 1948: }
1949:
1.100 markus 1950: static int
1.294 djm 1951: ssh_keysign(struct ssh *ssh, struct sshkey *key, u_char **sigp, size_t *lenp,
1.223 djm 1952: const u_char *data, size_t datalen)
1.100 markus 1953: {
1.223 djm 1954: struct sshbuf *b;
1.101 markus 1955: struct stat st;
1.100 markus 1956: pid_t pid;
1.304 deraadt 1957: int r, to[2], from[2], status;
1.295 djm 1958: int sock = ssh_packet_get_connection_in(ssh);
1.223 djm 1959: u_char rversion = 0, version = 2;
1960: void (*osigchld)(int);
1.100 markus 1961:
1.223 djm 1962: *sigp = NULL;
1963: *lenp = 0;
1.100 markus 1964:
1.306 deraadt 1965: if (stat(_PATH_SSH_KEY_SIGN, &st) == -1) {
1.331 djm 1966: error_f("not installed: %s", strerror(errno));
1.223 djm 1967: return -1;
1968: }
1969: if (fflush(stdout) != 0) {
1.331 djm 1970: error_f("fflush: %s", strerror(errno));
1.101 markus 1971: return -1;
1972: }
1.306 deraadt 1973: if (pipe(to) == -1) {
1.331 djm 1974: error_f("pipe: %s", strerror(errno));
1.100 markus 1975: return -1;
1976: }
1.306 deraadt 1977: if (pipe(from) == -1) {
1.331 djm 1978: error_f("pipe: %s", strerror(errno));
1.100 markus 1979: return -1;
1980: }
1.306 deraadt 1981: if ((pid = fork()) == -1) {
1.331 djm 1982: error_f("fork: %s", strerror(errno));
1.100 markus 1983: return -1;
1984: }
1.317 dtucker 1985: osigchld = ssh_signal(SIGCHLD, SIG_DFL);
1.100 markus 1986: if (pid == 0) {
1987: close(from[0]);
1.306 deraadt 1988: if (dup2(from[1], STDOUT_FILENO) == -1)
1.331 djm 1989: fatal_f("dup2: %s", strerror(errno));
1.100 markus 1990: close(to[1]);
1.306 deraadt 1991: if (dup2(to[0], STDIN_FILENO) == -1)
1.331 djm 1992: fatal_f("dup2: %s", strerror(errno));
1.103 markus 1993: close(from[1]);
1994: close(to[0]);
1.304 deraadt 1995:
1.306 deraadt 1996: if (dup2(sock, STDERR_FILENO + 1) == -1)
1.331 djm 1997: fatal_f("dup2: %s", strerror(errno));
1.304 deraadt 1998: sock = STDERR_FILENO + 1;
1999: fcntl(sock, F_SETFD, 0); /* keep the socket on exec */
1.223 djm 2000: closefrom(sock + 1);
1.304 deraadt 2001:
1.331 djm 2002: debug3_f("[child] pid=%ld, exec %s",
2003: (long)getpid(), _PATH_SSH_KEY_SIGN);
1.233 mmcc 2004: execl(_PATH_SSH_KEY_SIGN, _PATH_SSH_KEY_SIGN, (char *)NULL);
1.331 djm 2005: fatal_f("exec(%s): %s", _PATH_SSH_KEY_SIGN,
1.100 markus 2006: strerror(errno));
2007: }
2008: close(from[1]);
2009: close(to[0]);
1.305 djm 2010: sock = STDERR_FILENO + 1;
1.100 markus 2011:
1.223 djm 2012: if ((b = sshbuf_new()) == NULL)
1.331 djm 2013: fatal_f("sshbuf_new failed");
1.223 djm 2014: /* send # of sock, data to be signed */
1.253 djm 2015: if ((r = sshbuf_put_u32(b, sock)) != 0 ||
1.223 djm 2016: (r = sshbuf_put_string(b, data, datalen)) != 0)
1.331 djm 2017: fatal_fr(r, "buffer error");
1.223 djm 2018: if (ssh_msg_send(to[1], version, b) == -1)
1.331 djm 2019: fatal_f("couldn't send request");
1.223 djm 2020: sshbuf_reset(b);
2021: r = ssh_msg_recv(from[0], b);
1.101 markus 2022: close(from[0]);
2023: close(to[1]);
1.223 djm 2024: if (r < 0) {
1.331 djm 2025: error_f("no reply");
1.223 djm 2026: goto fail;
2027: }
1.101 markus 2028:
1.223 djm 2029: errno = 0;
1.306 deraadt 2030: while (waitpid(pid, &status, 0) == -1) {
1.223 djm 2031: if (errno != EINTR) {
1.331 djm 2032: error_f("waitpid %ld: %s", (long)pid, strerror(errno));
1.223 djm 2033: goto fail;
2034: }
2035: }
2036: if (!WIFEXITED(status)) {
1.331 djm 2037: error_f("exited abnormally");
1.223 djm 2038: goto fail;
2039: }
2040: if (WEXITSTATUS(status) != 0) {
1.331 djm 2041: error_f("exited with status %d", WEXITSTATUS(status));
1.223 djm 2042: goto fail;
2043: }
2044: if ((r = sshbuf_get_u8(b, &rversion)) != 0) {
1.331 djm 2045: error_fr(r, "buffer error");
1.223 djm 2046: goto fail;
2047: }
2048: if (rversion != version) {
1.331 djm 2049: error_f("bad version");
1.223 djm 2050: goto fail;
2051: }
2052: if ((r = sshbuf_get_string(b, sigp, lenp)) != 0) {
1.331 djm 2053: error_fr(r, "buffer error");
1.223 djm 2054: fail:
1.317 dtucker 2055: ssh_signal(SIGCHLD, osigchld);
1.223 djm 2056: sshbuf_free(b);
1.100 markus 2057: return -1;
2058: }
1.317 dtucker 2059: ssh_signal(SIGCHLD, osigchld);
1.223 djm 2060: sshbuf_free(b);
1.100 markus 2061:
2062: return 0;
2063: }
2064:
1.302 djm 2065: static int
1.295 djm 2066: userauth_hostbased(struct ssh *ssh)
1.68 markus 2067: {
1.295 djm 2068: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.223 djm 2069: struct sshkey *private = NULL;
2070: struct sshbuf *b = NULL;
2071: u_char *sig = NULL, *keyblob = NULL;
2072: char *fp = NULL, *chost = NULL, *lname = NULL;
2073: size_t siglen = 0, keylen = 0;
2074: int i, r, success = 0;
2075:
2076: if (authctxt->ktypes == NULL) {
2077: authctxt->oktypes = xstrdup(options.hostbased_key_types);
2078: authctxt->ktypes = authctxt->oktypes;
2079: }
1.213 djm 2080:
1.223 djm 2081: /*
2082: * Work through each listed type pattern in HostbasedKeyTypes,
2083: * trying each hostkey that matches the type in turn.
2084: */
2085: for (;;) {
2086: if (authctxt->active_ktype == NULL)
2087: authctxt->active_ktype = strsep(&authctxt->ktypes, ",");
2088: if (authctxt->active_ktype == NULL ||
2089: *authctxt->active_ktype == '\0')
2090: break;
1.331 djm 2091: debug3_f("trying key type %s", authctxt->active_ktype);
1.68 markus 2092:
1.223 djm 2093: /* check for a useful key */
2094: private = NULL;
2095: for (i = 0; i < authctxt->sensitive->nkeys; i++) {
2096: if (authctxt->sensitive->keys[i] == NULL ||
2097: authctxt->sensitive->keys[i]->type == KEY_UNSPEC)
2098: continue;
2099: if (match_pattern_list(
2100: sshkey_ssh_name(authctxt->sensitive->keys[i]),
1.224 djm 2101: authctxt->active_ktype, 0) != 1)
1.223 djm 2102: continue;
1.68 markus 2103: /* we take and free the key */
1.223 djm 2104: private = authctxt->sensitive->keys[i];
2105: authctxt->sensitive->keys[i] = NULL;
1.68 markus 2106: break;
2107: }
1.223 djm 2108: /* Found one */
2109: if (private != NULL)
2110: break;
2111: /* No more keys of this type; advance */
2112: authctxt->active_ktype = NULL;
1.68 markus 2113: }
1.223 djm 2114: if (private == NULL) {
2115: free(authctxt->oktypes);
2116: authctxt->oktypes = authctxt->ktypes = NULL;
2117: authctxt->active_ktype = NULL;
1.109 markus 2118: debug("No more client hostkeys for hostbased authentication.");
1.223 djm 2119: goto out;
1.68 markus 2120: }
1.211 djm 2121:
1.223 djm 2122: if ((fp = sshkey_fingerprint(private, options.fingerprint_hash,
2123: SSH_FP_DEFAULT)) == NULL) {
1.331 djm 2124: error_f("sshkey_fingerprint failed");
1.223 djm 2125: goto out;
1.68 markus 2126: }
1.331 djm 2127: debug_f("trying hostkey %s %s", sshkey_ssh_name(private), fp);
1.211 djm 2128:
1.84 markus 2129: /* figure out a name for the client host */
1.295 djm 2130: lname = get_local_name(ssh_packet_get_connection_in(ssh));
2131: if (lname == NULL) {
1.331 djm 2132: error_f("cannot get local ipaddr/name");
1.223 djm 2133: goto out;
1.84 markus 2134: }
1.223 djm 2135:
2136: /* XXX sshbuf_put_stringf? */
2137: xasprintf(&chost, "%s.", lname);
1.331 djm 2138: debug2_f("chost %s", chost);
1.84 markus 2139:
1.68 markus 2140: /* construct data */
1.223 djm 2141: if ((b = sshbuf_new()) == NULL) {
1.331 djm 2142: error_f("sshbuf_new failed");
1.223 djm 2143: goto out;
2144: }
2145: if ((r = sshkey_to_blob(private, &keyblob, &keylen)) != 0) {
1.331 djm 2146: error_fr(r, "sshkey_to_blob");
1.223 djm 2147: goto out;
2148: }
2149: if ((r = sshbuf_put_string(b, session_id2, session_id2_len)) != 0 ||
2150: (r = sshbuf_put_u8(b, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
2151: (r = sshbuf_put_cstring(b, authctxt->server_user)) != 0 ||
1.267 djm 2152: (r = sshbuf_put_cstring(b, authctxt->service)) != 0 ||
1.223 djm 2153: (r = sshbuf_put_cstring(b, authctxt->method->name)) != 0 ||
1.279 markus 2154: (r = sshbuf_put_cstring(b, sshkey_ssh_name(private))) != 0 ||
1.223 djm 2155: (r = sshbuf_put_string(b, keyblob, keylen)) != 0 ||
2156: (r = sshbuf_put_cstring(b, chost)) != 0 ||
2157: (r = sshbuf_put_cstring(b, authctxt->local_user)) != 0) {
1.331 djm 2158: error_fr(r, "buffer error");
1.223 djm 2159: goto out;
2160: }
2161:
1.68 markus 2162: #ifdef DEBUG_PK
1.223 djm 2163: sshbuf_dump(b, stderr);
1.68 markus 2164: #endif
1.294 djm 2165: if ((r = ssh_keysign(ssh, private, &sig, &siglen,
2166: sshbuf_ptr(b), sshbuf_len(b))) != 0) {
1.223 djm 2167: error("sign using hostkey %s %s failed",
2168: sshkey_ssh_name(private), fp);
2169: goto out;
2170: }
2171: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
2172: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
2173: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
2174: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1.279 markus 2175: (r = sshpkt_put_cstring(ssh, sshkey_ssh_name(private))) != 0 ||
1.223 djm 2176: (r = sshpkt_put_string(ssh, keyblob, keylen)) != 0 ||
2177: (r = sshpkt_put_cstring(ssh, chost)) != 0 ||
2178: (r = sshpkt_put_cstring(ssh, authctxt->local_user)) != 0 ||
2179: (r = sshpkt_put_string(ssh, sig, siglen)) != 0 ||
2180: (r = sshpkt_send(ssh)) != 0) {
1.331 djm 2181: error_fr(r, "packet error");
1.223 djm 2182: goto out;
2183: }
2184: success = 1;
2185:
2186: out:
1.278 markus 2187: if (sig != NULL)
2188: freezero(sig, siglen);
1.223 djm 2189: free(keyblob);
2190: free(lname);
2191: free(fp);
1.197 djm 2192: free(chost);
1.223 djm 2193: sshkey_free(private);
2194: sshbuf_free(b);
1.68 markus 2195:
1.223 djm 2196: return success;
1.23 markus 2197: }
1.170 djm 2198:
1.20 markus 2199: /* find auth method */
2200:
2201: /*
2202: * given auth method name, if configurable options permit this method fill
2203: * in auth_ident field and return true, otherwise return false.
2204: */
1.76 itojun 2205: static int
1.20 markus 2206: authmethod_is_enabled(Authmethod *method)
2207: {
2208: if (method == NULL)
2209: return 0;
2210: /* return false if options indicate this method is disabled */
2211: if (method->enabled == NULL || *method->enabled == 0)
2212: return 0;
2213: /* return false if batch mode is enabled but method needs interactive mode */
2214: if (method->batch_flag != NULL && *method->batch_flag != 0)
2215: return 0;
2216: return 1;
2217: }
2218:
1.76 itojun 2219: static Authmethod *
1.20 markus 2220: authmethod_lookup(const char *name)
1.1 markus 2221: {
1.20 markus 2222: Authmethod *method = NULL;
2223: if (name != NULL)
2224: for (method = authmethods; method->name != NULL; method++)
2225: if (strcmp(name, method->name) == 0)
2226: return method;
2227: debug2("Unrecognized authentication method name: %s", name ? name : "NULL");
2228: return NULL;
2229: }
1.1 markus 2230:
1.53 markus 2231: /* XXX internal state */
2232: static Authmethod *current = NULL;
2233: static char *supported = NULL;
2234: static char *preferred = NULL;
1.105 deraadt 2235:
1.20 markus 2236: /*
2237: * Given the authentication method list sent by the server, return the
2238: * next method we should try. If the server initially sends a nil list,
1.67 markus 2239: * use a built-in default list.
1.41 stevesk 2240: */
1.76 itojun 2241: static Authmethod *
1.20 markus 2242: authmethod_get(char *authlist)
2243: {
1.53 markus 2244: char *name = NULL;
1.97 markus 2245: u_int next;
1.41 stevesk 2246:
1.20 markus 2247: /* Use a suitable default if we're passed a nil list. */
2248: if (authlist == NULL || strlen(authlist) == 0)
1.53 markus 2249: authlist = options.preferred_authentications;
1.20 markus 2250:
1.53 markus 2251: if (supported == NULL || strcmp(authlist, supported) != 0) {
2252: debug3("start over, passed a different list %s", authlist);
1.197 djm 2253: free(supported);
1.53 markus 2254: supported = xstrdup(authlist);
2255: preferred = options.preferred_authentications;
2256: debug3("preferred %s", preferred);
2257: current = NULL;
2258: } else if (current != NULL && authmethod_is_enabled(current))
2259: return current;
1.20 markus 2260:
1.53 markus 2261: for (;;) {
2262: if ((name = match_list(preferred, supported, &next)) == NULL) {
1.109 markus 2263: debug("No more authentication methods to try.");
1.53 markus 2264: current = NULL;
2265: return NULL;
2266: }
2267: preferred += next;
1.23 markus 2268: debug3("authmethod_lookup %s", name);
1.53 markus 2269: debug3("remaining preferred: %s", preferred);
2270: if ((current = authmethod_lookup(name)) != NULL &&
2271: authmethod_is_enabled(current)) {
1.23 markus 2272: debug3("authmethod_is_enabled %s", name);
1.109 markus 2273: debug("Next authentication method: %s", name);
1.197 djm 2274: free(name);
1.53 markus 2275: return current;
1.23 markus 2276: }
1.198 dtucker 2277: free(name);
1.1 markus 2278: }
1.53 markus 2279: }
1.1 markus 2280:
1.79 stevesk 2281: static char *
1.53 markus 2282: authmethods_get(void)
2283: {
2284: Authmethod *method = NULL;
1.278 markus 2285: struct sshbuf *b;
1.93 markus 2286: char *list;
1.278 markus 2287: int r;
1.27 provos 2288:
1.278 markus 2289: if ((b = sshbuf_new()) == NULL)
1.331 djm 2290: fatal_f("sshbuf_new failed");
1.53 markus 2291: for (method = authmethods; method->name != NULL; method++) {
2292: if (authmethod_is_enabled(method)) {
1.278 markus 2293: if ((r = sshbuf_putf(b, "%s%s",
2294: sshbuf_len(b) ? "," : "", method->name)) != 0)
1.331 djm 2295: fatal_fr(r, "buffer error");
1.53 markus 2296: }
2297: }
1.278 markus 2298: if ((list = sshbuf_dup_string(b)) == NULL)
1.331 djm 2299: fatal_f("sshbuf_dup_string failed");
1.278 markus 2300: sshbuf_free(b);
1.93 markus 2301: return list;
1.1 markus 2302: }
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