Annotation of src/usr.bin/ssh/sshconnect2.c, Revision 1.338
1.338 ! djm 1: /* $OpenBSD: sshconnect2.c,v 1.337 2020/12/20 23:36:51 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:
1.338 ! djm 90: static char *xxx_host;
! 91: static struct sockaddr *xxx_hostaddr;
! 92: static const struct ssh_conn_info *xxx_conn_info;
1.61 markus 93:
1.76 itojun 94: static int
1.259 markus 95: verify_host_key_callback(struct sshkey *hostkey, struct ssh *ssh)
1.61 markus 96: {
1.338 ! djm 97: if (verify_host_key(xxx_host, xxx_hostaddr, hostkey,
! 98: xxx_conn_info) == -1)
1.83 markus 99: fatal("Host key verification failed.");
1.61 markus 100: return 0;
101: }
102:
1.326 djm 103: /* Returns the first item from a comma-separated algorithm list */
104: static char *
105: first_alg(const char *algs)
106: {
107: char *ret, *cp;
108:
109: ret = xstrdup(algs);
110: if ((cp = strchr(ret, ',')) != NULL)
111: *cp = '\0';
112: return ret;
113: }
114:
1.186 djm 115: static char *
1.338 ! djm 116: order_hostkeyalgs(char *host, struct sockaddr *hostaddr, u_short port,
! 117: const struct ssh_conn_info *cinfo)
1.186 djm 118: {
1.326 djm 119: char *oavail = NULL, *avail = NULL, *first = NULL, *last = NULL;
120: char *alg = NULL, *hostname = NULL, *ret = NULL, *best = NULL;
1.186 djm 121: size_t maxlen;
1.326 djm 122: struct hostkeys *hostkeys = NULL;
1.186 djm 123: int ktype;
1.188 djm 124: u_int i;
1.186 djm 125:
126: /* Find all hostkeys for this hostname */
127: get_hostfile_hostname_ipaddr(host, hostaddr, port, &hostname, NULL);
128: hostkeys = init_hostkeys();
1.188 djm 129: for (i = 0; i < options.num_user_hostfiles; i++)
1.337 djm 130: load_hostkeys(hostkeys, hostname, options.user_hostfiles[i], 0);
131: for (i = 0; i < options.num_system_hostfiles; i++) {
132: load_hostkeys(hostkeys, hostname,
133: options.system_hostfiles[i], 0);
134: }
1.326 djm 135: /*
136: * If a plain public key exists that matches the type of the best
137: * preference HostkeyAlgorithms, then use the whole list as is.
138: * Note that we ignore whether the best preference algorithm is a
139: * certificate type, as sshconnect.c will downgrade certs to
140: * plain keys if necessary.
141: */
142: best = first_alg(options.hostkeyalgorithms);
143: if (lookup_key_in_hostkeys_by_type(hostkeys,
1.328 djm 144: sshkey_type_plain(sshkey_type_from_name(best)),
145: sshkey_ecdsa_nid_from_name(best), NULL)) {
1.331 djm 146: debug3_f("have matching best-preference key type %s, "
147: "using HostkeyAlgorithms verbatim", best);
1.326 djm 148: ret = xstrdup(options.hostkeyalgorithms);
149: goto out;
150: }
151:
152: /*
153: * Otherwise, prefer the host key algorithms that match known keys
154: * while keeping the ordering of HostkeyAlgorithms as much as possible.
155: */
1.320 djm 156: oavail = avail = xstrdup(options.hostkeyalgorithms);
1.186 djm 157: maxlen = strlen(avail) + 1;
158: first = xmalloc(maxlen);
159: last = xmalloc(maxlen);
160: *first = *last = '\0';
161:
162: #define ALG_APPEND(to, from) \
163: do { \
164: if (*to != '\0') \
165: strlcat(to, ",", maxlen); \
166: strlcat(to, from, maxlen); \
167: } while (0)
168:
169: while ((alg = strsep(&avail, ",")) && *alg != '\0') {
1.214 djm 170: if ((ktype = sshkey_type_from_name(alg)) == KEY_UNSPEC)
1.331 djm 171: fatal_f("unknown alg %s", alg);
1.322 djm 172: /*
173: * If we have a @cert-authority marker in known_hosts then
174: * prefer all certificate algorithms.
175: */
176: if (sshkey_type_is_cert(ktype) &&
177: lookup_marker_in_hostkeys(hostkeys, MRK_CA)) {
178: ALG_APPEND(first, alg);
179: continue;
180: }
181: /* If the key appears in known_hosts then prefer it */
1.186 djm 182: if (lookup_key_in_hostkeys_by_type(hostkeys,
1.328 djm 183: sshkey_type_plain(ktype),
184: sshkey_ecdsa_nid_from_name(alg), NULL)) {
1.186 djm 185: ALG_APPEND(first, alg);
1.322 djm 186: continue;
187: }
188: /* Otherwise, put it last */
189: ALG_APPEND(last, alg);
1.186 djm 190: }
191: #undef ALG_APPEND
1.216 djm 192: xasprintf(&ret, "%s%s%s", first,
193: (*first == '\0' || *last == '\0') ? "" : ",", last);
1.186 djm 194: if (*first != '\0')
1.331 djm 195: debug3_f("prefer hostkeyalgs: %s", first);
1.186 djm 196:
1.326 djm 197: out:
198: free(best);
1.197 djm 199: free(first);
200: free(last);
201: free(hostname);
202: free(oavail);
1.186 djm 203: free_hostkeys(hostkeys);
204:
205: return ret;
206: }
207:
1.1 markus 208: void
1.338 ! djm 209: ssh_kex2(struct ssh *ssh, char *host, struct sockaddr *hostaddr, u_short port,
! 210: const struct ssh_conn_info *cinfo)
1.22 provos 211: {
1.205 markus 212: char *myproposal[PROPOSAL_MAX] = { KEX_CLIENT };
1.275 djm 213: char *s, *all_key;
1.320 djm 214: int r, use_known_hosts_order = 0;
1.61 markus 215:
216: xxx_host = host;
217: xxx_hostaddr = hostaddr;
1.338 ! djm 218: xxx_conn_info = cinfo;
1.22 provos 219:
1.320 djm 220: /*
221: * If the user has not specified HostkeyAlgorithms, or has only
222: * appended or removed algorithms from that list then prefer algorithms
223: * that are in the list that are supported by known_hosts keys.
224: */
225: if (options.hostkeyalgorithms == NULL ||
226: options.hostkeyalgorithms[0] == '-' ||
227: options.hostkeyalgorithms[0] == '+')
228: use_known_hosts_order = 1;
229:
230: /* Expand or fill in HostkeyAlgorithms */
231: all_key = sshkey_alg_list(0, 0, 1, ',');
1.333 djm 232: if ((r = kex_assemble_names(&options.hostkeyalgorithms,
233: kex_default_pk_alg(), all_key)) != 0)
234: fatal_fr(r, "kex_assemble_namelist");
1.320 djm 235: free(all_key);
236:
1.231 markus 237: if ((s = kex_names_cat(options.kex_algorithms, "ext-info-c")) == NULL)
1.331 djm 238: fatal_f("kex_names_cat");
1.284 djm 239: myproposal[PROPOSAL_KEX_ALGS] = compat_kex_proposal(s);
1.60 stevesk 240: myproposal[PROPOSAL_ENC_ALGS_CTOS] =
1.284 djm 241: compat_cipher_proposal(options.ciphers);
1.60 stevesk 242: myproposal[PROPOSAL_ENC_ALGS_STOC] =
1.284 djm 243: compat_cipher_proposal(options.ciphers);
1.245 dtucker 244: myproposal[PROPOSAL_COMP_ALGS_CTOS] =
1.318 dtucker 245: myproposal[PROPOSAL_COMP_ALGS_STOC] =
246: (char *)compression_alg_list(options.compression);
1.226 djm 247: myproposal[PROPOSAL_MAC_ALGS_CTOS] =
248: myproposal[PROPOSAL_MAC_ALGS_STOC] = options.macs;
1.320 djm 249: if (use_known_hosts_order) {
250: /* Query known_hosts and prefer algorithms that appear there */
1.88 deraadt 251: myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] =
1.320 djm 252: compat_pkalg_proposal(
1.338 ! djm 253: order_hostkeyalgs(host, hostaddr, port, cinfo));
1.226 djm 254: } else {
1.320 djm 255: /* Use specified HostkeyAlgorithms exactly */
1.186 djm 256: myproposal[PROPOSAL_SERVER_HOST_KEY_ALGS] =
1.320 djm 257: compat_pkalg_proposal(options.hostkeyalgorithms);
1.186 djm 258: }
1.115 markus 259:
1.196 dtucker 260: if (options.rekey_limit || options.rekey_interval)
1.294 djm 261: ssh_packet_set_rekey_limits(ssh, options.rekey_limit,
1.254 dtucker 262: options.rekey_interval);
1.22 provos 263:
1.65 markus 264: /* start key exchange */
1.291 djm 265: if ((r = kex_setup(ssh, myproposal)) != 0)
1.331 djm 266: fatal_r(r, "kex_setup");
1.207 markus 267: #ifdef WITH_OPENSSL
1.301 djm 268: ssh->kex->kex[KEX_DH_GRP1_SHA1] = kex_gen_client;
269: ssh->kex->kex[KEX_DH_GRP14_SHA1] = kex_gen_client;
270: ssh->kex->kex[KEX_DH_GRP14_SHA256] = kex_gen_client;
271: ssh->kex->kex[KEX_DH_GRP16_SHA512] = kex_gen_client;
272: ssh->kex->kex[KEX_DH_GRP18_SHA512] = kex_gen_client;
1.291 djm 273: ssh->kex->kex[KEX_DH_GEX_SHA1] = kexgex_client;
274: ssh->kex->kex[KEX_DH_GEX_SHA256] = kexgex_client;
1.301 djm 275: ssh->kex->kex[KEX_ECDH_SHA2] = kex_gen_client;
1.207 markus 276: #endif
1.301 djm 277: ssh->kex->kex[KEX_C25519_SHA256] = kex_gen_client;
278: ssh->kex->kex[KEX_KEM_SNTRUP4591761X25519_SHA512] = kex_gen_client;
1.291 djm 279: ssh->kex->verify_host_key=&verify_host_key_callback;
1.22 provos 280:
1.291 djm 281: ssh_dispatch_run_fatal(ssh, DISPATCH_BLOCK, &ssh->kex->done);
1.173 andreas 282:
1.231 markus 283: /* remove ext-info from the KEX proposals for rekeying */
284: myproposal[PROPOSAL_KEX_ALGS] =
1.284 djm 285: compat_kex_proposal(options.kex_algorithms);
1.291 djm 286: if ((r = kex_prop2buf(ssh->kex->my, myproposal)) != 0)
1.331 djm 287: fatal_r(r, "kex_prop2buf");
1.62 markus 288:
1.291 djm 289: session_id2 = ssh->kex->session_id;
290: session_id2_len = ssh->kex->session_id_len;
1.22 provos 291:
292: #ifdef DEBUG_KEXDH
293: /* send 1st encrypted/maced/compressed message */
1.278 markus 294: if ((r = sshpkt_start(ssh, SSH2_MSG_IGNORE)) != 0 ||
295: (r = sshpkt_put_cstring(ssh, "markus")) != 0 ||
1.280 markus 296: (r = sshpkt_send(ssh)) != 0 ||
297: (r = ssh_packet_write_wait(ssh)) != 0)
1.331 djm 298: fatal_fr(r, "send packet");
1.22 provos 299: #endif
1.1 markus 300: }
1.11 markus 301:
1.1 markus 302: /*
303: * Authenticate user
304: */
1.20 markus 305:
1.214 djm 306: typedef struct cauthctxt Authctxt;
307: typedef struct cauthmethod Authmethod;
1.117 markus 308: typedef struct identity Identity;
309: typedef struct idlist Idlist;
1.20 markus 310:
1.117 markus 311: struct identity {
312: TAILQ_ENTRY(identity) next;
1.214 djm 313: int agent_fd; /* >=0 if agent supports key */
314: struct sshkey *key; /* public/private key */
1.117 markus 315: char *filename; /* comment for agent-only keys */
316: int tried;
317: int isprivate; /* key points to the private key */
1.191 dtucker 318: int userprovided;
1.117 markus 319: };
320: TAILQ_HEAD(idlist, identity);
1.20 markus 321:
1.214 djm 322: struct cauthctxt {
1.20 markus 323: const char *server_user;
1.68 markus 324: const char *local_user;
1.20 markus 325: const char *host;
326: const char *service;
1.214 djm 327: struct cauthmethod *method;
1.183 djm 328: sig_atomic_t success;
1.51 markus 329: char *authlist;
1.302 djm 330: #ifdef GSSAPI
331: /* gssapi */
332: gss_OID_set gss_supported_mechs;
333: u_int mech_tried;
334: #endif
1.68 markus 335: /* pubkey */
1.214 djm 336: struct idlist keys;
337: int agent_fd;
1.68 markus 338: /* hostbased */
1.100 markus 339: Sensitive *sensitive;
1.223 djm 340: char *oktypes, *ktypes;
341: const char *active_ktype;
1.82 markus 342: /* kbd-interactive */
343: int info_req_seen;
1.292 djm 344: int attempt_kbdint;
345: /* password */
346: int attempt_passwd;
1.121 markus 347: /* generic */
348: void *methoddata;
1.20 markus 349: };
1.214 djm 350:
351: struct cauthmethod {
1.20 markus 352: char *name; /* string to compare against server's list */
1.295 djm 353: int (*userauth)(struct ssh *ssh);
354: void (*cleanup)(struct ssh *ssh);
1.20 markus 355: int *enabled; /* flag in option struct that enables method */
356: int *batch_flag; /* flag in option struct that disables method */
357: };
358:
1.302 djm 359: static int input_userauth_service_accept(int, u_int32_t, struct ssh *);
360: static int input_userauth_ext_info(int, u_int32_t, struct ssh *);
361: static int input_userauth_success(int, u_int32_t, struct ssh *);
362: static int input_userauth_failure(int, u_int32_t, struct ssh *);
363: static int input_userauth_banner(int, u_int32_t, struct ssh *);
364: static int input_userauth_error(int, u_int32_t, struct ssh *);
365: static int input_userauth_info_req(int, u_int32_t, struct ssh *);
366: static int input_userauth_pk_ok(int, u_int32_t, struct ssh *);
367: static int input_userauth_passwd_changereq(int, u_int32_t, struct ssh *);
368:
369: static int userauth_none(struct ssh *);
370: static int userauth_pubkey(struct ssh *);
371: static int userauth_passwd(struct ssh *);
372: static int userauth_kbdint(struct ssh *);
373: static int userauth_hostbased(struct ssh *);
1.20 markus 374:
1.121 markus 375: #ifdef GSSAPI
1.302 djm 376: static int userauth_gssapi(struct ssh *);
377: static void userauth_gssapi_cleanup(struct ssh *);
378: static int input_gssapi_response(int type, u_int32_t, struct ssh *);
379: static int input_gssapi_token(int type, u_int32_t, struct ssh *);
380: static int input_gssapi_error(int, u_int32_t, struct ssh *);
381: static int input_gssapi_errtok(int, u_int32_t, struct ssh *);
1.121 markus 382: #endif
383:
1.295 djm 384: void userauth(struct ssh *, char *);
1.51 markus 385:
1.303 djm 386: static void pubkey_cleanup(struct ssh *);
1.295 djm 387: static int sign_and_send_pubkey(struct ssh *ssh, Identity *);
1.117 markus 388: static void pubkey_prepare(Authctxt *);
1.251 djm 389: static void pubkey_reset(Authctxt *);
1.259 markus 390: static struct sshkey *load_identity_file(Identity *);
1.76 itojun 391:
392: static Authmethod *authmethod_get(char *authlist);
393: static Authmethod *authmethod_lookup(const char *name);
394: static char *authmethods_get(void);
1.20 markus 395:
396: Authmethod authmethods[] = {
1.121 markus 397: #ifdef GSSAPI
1.132 markus 398: {"gssapi-with-mic",
1.121 markus 399: userauth_gssapi,
1.302 djm 400: userauth_gssapi_cleanup,
1.121 markus 401: &options.gss_authentication,
402: NULL},
403: #endif
1.81 markus 404: {"hostbased",
405: userauth_hostbased,
1.170 djm 406: NULL,
1.81 markus 407: &options.hostbased_authentication,
408: NULL},
1.20 markus 409: {"publickey",
410: userauth_pubkey,
1.303 djm 411: NULL,
1.28 markus 412: &options.pubkey_authentication,
1.20 markus 413: NULL},
1.81 markus 414: {"keyboard-interactive",
415: userauth_kbdint,
1.170 djm 416: NULL,
1.81 markus 417: &options.kbd_interactive_authentication,
418: &options.batch_mode},
1.20 markus 419: {"password",
420: userauth_passwd,
1.170 djm 421: NULL,
1.20 markus 422: &options.password_authentication,
1.23 markus 423: &options.batch_mode},
424: {"none",
425: userauth_none,
426: NULL,
1.170 djm 427: NULL,
1.23 markus 428: NULL},
1.170 djm 429: {NULL, NULL, NULL, NULL, NULL}
1.20 markus 430: };
431:
432: void
1.291 djm 433: ssh_userauth2(struct ssh *ssh, const char *local_user,
434: const char *server_user, char *host, Sensitive *sensitive)
1.20 markus 435: {
436: Authctxt authctxt;
1.231 markus 437: int r;
1.39 markus 438:
1.73 markus 439: if (options.challenge_response_authentication)
1.39 markus 440: options.kbd_interactive_authentication = 1;
1.53 markus 441: if (options.preferred_authentications == NULL)
442: options.preferred_authentications = authmethods_get();
443:
1.20 markus 444: /* setup authentication context */
1.82 markus 445: memset(&authctxt, 0, sizeof(authctxt));
1.20 markus 446: authctxt.server_user = server_user;
1.68 markus 447: authctxt.local_user = local_user;
1.20 markus 448: authctxt.host = host;
449: authctxt.service = "ssh-connection"; /* service name */
450: authctxt.success = 0;
1.23 markus 451: authctxt.method = authmethod_lookup("none");
1.51 markus 452: authctxt.authlist = NULL;
1.121 markus 453: authctxt.methoddata = NULL;
1.100 markus 454: authctxt.sensitive = sensitive;
1.223 djm 455: authctxt.active_ktype = authctxt.oktypes = authctxt.ktypes = NULL;
1.82 markus 456: authctxt.info_req_seen = 0;
1.292 djm 457: authctxt.attempt_kbdint = 0;
458: authctxt.attempt_passwd = 0;
1.302 djm 459: #if GSSAPI
460: authctxt.gss_supported_mechs = NULL;
461: authctxt.mech_tried = 0;
462: #endif
1.215 djm 463: authctxt.agent_fd = -1;
1.289 djm 464: pubkey_prepare(&authctxt);
1.291 djm 465: if (authctxt.method == NULL) {
1.331 djm 466: fatal_f("internal error: cannot send userauth none request");
1.291 djm 467: }
1.20 markus 468:
1.231 markus 469: if ((r = sshpkt_start(ssh, SSH2_MSG_SERVICE_REQUEST)) != 0 ||
470: (r = sshpkt_put_cstring(ssh, "ssh-userauth")) != 0 ||
471: (r = sshpkt_send(ssh)) != 0)
1.331 djm 472: fatal_fr(r, "send packet");
1.231 markus 473:
1.260 markus 474: ssh->authctxt = &authctxt;
1.231 markus 475: ssh_dispatch_init(ssh, &input_userauth_error);
476: ssh_dispatch_set(ssh, SSH2_MSG_EXT_INFO, &input_userauth_ext_info);
477: ssh_dispatch_set(ssh, SSH2_MSG_SERVICE_ACCEPT, &input_userauth_service_accept);
1.263 markus 478: ssh_dispatch_run_fatal(ssh, DISPATCH_BLOCK, &authctxt.success); /* loop until success */
1.303 djm 479: pubkey_cleanup(ssh);
1.260 markus 480: ssh->authctxt = NULL;
1.20 markus 481:
1.231 markus 482: ssh_dispatch_range(ssh, SSH2_MSG_USERAUTH_MIN, SSH2_MSG_USERAUTH_MAX, NULL);
1.119 markus 483:
1.248 dtucker 484: if (!authctxt.success)
485: fatal("Authentication failed.");
1.109 markus 486: debug("Authentication succeeded (%s).", authctxt.method->name);
1.20 markus 487: }
1.119 markus 488:
1.231 markus 489: /* ARGSUSED */
1.302 djm 490: static int
1.261 markus 491: input_userauth_service_accept(int type, u_int32_t seq, struct ssh *ssh)
1.231 markus 492: {
493: int r;
494:
495: if (ssh_packet_remaining(ssh) > 0) {
496: char *reply;
497:
498: if ((r = sshpkt_get_cstring(ssh, &reply, NULL)) != 0)
499: goto out;
500: debug2("service_accept: %s", reply);
501: free(reply);
502: } else {
503: debug2("buggy server: service_accept w/o service");
504: }
505: if ((r = sshpkt_get_end(ssh)) != 0)
506: goto out;
507: debug("SSH2_MSG_SERVICE_ACCEPT received");
508:
509: /* initial userauth request */
1.295 djm 510: userauth_none(ssh);
1.231 markus 511:
512: ssh_dispatch_set(ssh, SSH2_MSG_EXT_INFO, &input_userauth_error);
513: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_SUCCESS, &input_userauth_success);
514: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_FAILURE, &input_userauth_failure);
515: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_BANNER, &input_userauth_banner);
516: r = 0;
517: out:
518: return r;
519: }
520:
521: /* ARGSUSED */
1.302 djm 522: static int
1.261 markus 523: input_userauth_ext_info(int type, u_int32_t seqnr, struct ssh *ssh)
1.231 markus 524: {
1.261 markus 525: return kex_input_ext_info(type, seqnr, ssh);
1.231 markus 526: }
527:
1.20 markus 528: void
1.295 djm 529: userauth(struct ssh *ssh, char *authlist)
1.51 markus 530: {
1.295 djm 531: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.278 markus 532:
1.170 djm 533: if (authctxt->method != NULL && authctxt->method->cleanup != NULL)
1.295 djm 534: authctxt->method->cleanup(ssh);
1.170 djm 535:
1.197 djm 536: free(authctxt->methoddata);
537: authctxt->methoddata = NULL;
1.51 markus 538: if (authlist == NULL) {
539: authlist = authctxt->authlist;
540: } else {
1.197 djm 541: free(authctxt->authlist);
1.51 markus 542: authctxt->authlist = authlist;
543: }
544: for (;;) {
545: Authmethod *method = authmethod_get(authlist);
546: if (method == NULL)
1.264 dtucker 547: fatal("%s@%s: Permission denied (%s).",
548: authctxt->server_user, authctxt->host, authlist);
1.51 markus 549: authctxt->method = method;
1.119 markus 550:
551: /* reset the per method handler */
1.278 markus 552: ssh_dispatch_range(ssh, SSH2_MSG_USERAUTH_PER_METHOD_MIN,
1.119 markus 553: SSH2_MSG_USERAUTH_PER_METHOD_MAX, NULL);
554:
555: /* and try new method */
1.295 djm 556: if (method->userauth(ssh) != 0) {
1.51 markus 557: debug2("we sent a %s packet, wait for reply", method->name);
558: break;
559: } else {
560: debug2("we did not send a packet, disable method");
561: method->enabled = NULL;
562: }
563: }
564: }
1.105 deraadt 565:
1.169 djm 566: /* ARGSUSED */
1.302 djm 567: static int
1.261 markus 568: input_userauth_error(int type, u_int32_t seq, struct ssh *ssh)
1.20 markus 569: {
1.331 djm 570: fatal_f("bad message during authentication: type %d", type);
1.218 markus 571: return 0;
1.35 markus 572: }
1.105 deraadt 573:
1.169 djm 574: /* ARGSUSED */
1.302 djm 575: static int
1.261 markus 576: input_userauth_banner(int type, u_int32_t seq, struct ssh *ssh)
1.35 markus 577: {
1.295 djm 578: char *msg = NULL;
1.294 djm 579: size_t len;
580: int r;
1.126 deraadt 581:
1.331 djm 582: debug3_f("entering");
1.294 djm 583: if ((r = sshpkt_get_cstring(ssh, &msg, &len)) != 0 ||
1.295 djm 584: (r = sshpkt_get_cstring(ssh, NULL, NULL)) != 0)
1.294 djm 585: goto out;
1.246 djm 586: if (len > 0 && options.log_level >= SYSLOG_LEVEL_INFO)
587: fmprintf(stderr, "%s", msg);
1.294 djm 588: r = 0;
589: out:
1.246 djm 590: free(msg);
1.294 djm 591: return r;
1.20 markus 592: }
1.105 deraadt 593:
1.169 djm 594: /* ARGSUSED */
1.302 djm 595: static int
1.261 markus 596: input_userauth_success(int type, u_int32_t seq, struct ssh *ssh)
1.20 markus 597: {
1.260 markus 598: Authctxt *authctxt = ssh->authctxt;
1.172 djm 599:
1.20 markus 600: if (authctxt == NULL)
1.331 djm 601: fatal_f("no authentication context");
1.197 djm 602: free(authctxt->authlist);
603: authctxt->authlist = NULL;
1.172 djm 604: if (authctxt->method != NULL && authctxt->method->cleanup != NULL)
1.295 djm 605: authctxt->method->cleanup(ssh);
1.197 djm 606: free(authctxt->methoddata);
607: authctxt->methoddata = NULL;
1.20 markus 608: authctxt->success = 1; /* break out */
1.218 markus 609: return 0;
1.20 markus 610: }
1.105 deraadt 611:
1.302 djm 612: #if 0
613: static int
1.261 markus 614: input_userauth_success_unexpected(int type, u_int32_t seq, struct ssh *ssh)
1.172 djm 615: {
1.260 markus 616: Authctxt *authctxt = ssh->authctxt;
1.172 djm 617:
618: if (authctxt == NULL)
1.331 djm 619: fatal_f("no authentication context");
1.172 djm 620:
621: fatal("Unexpected authentication success during %s.",
622: authctxt->method->name);
1.218 markus 623: return 0;
1.172 djm 624: }
1.302 djm 625: #endif
1.172 djm 626:
1.169 djm 627: /* ARGSUSED */
1.302 djm 628: static int
1.261 markus 629: input_userauth_failure(int type, u_int32_t seq, struct ssh *ssh)
1.20 markus 630: {
1.260 markus 631: Authctxt *authctxt = ssh->authctxt;
1.20 markus 632: char *authlist = NULL;
1.278 markus 633: u_char partial;
1.20 markus 634:
635: if (authctxt == NULL)
636: fatal("input_userauth_failure: no authentication context");
637:
1.307 dtucker 638: if (sshpkt_get_cstring(ssh, &authlist, NULL) != 0 ||
639: sshpkt_get_u8(ssh, &partial) != 0 ||
640: sshpkt_get_end(ssh) != 0)
1.278 markus 641: goto out;
1.20 markus 642:
1.193 markus 643: if (partial != 0) {
1.247 dtucker 644: verbose("Authenticated with partial success.");
1.193 markus 645: /* reset state */
1.251 djm 646: pubkey_reset(authctxt);
1.193 markus 647: }
1.109 markus 648: debug("Authentications that can continue: %s", authlist);
1.20 markus 649:
1.295 djm 650: userauth(ssh, authlist);
1.278 markus 651: authlist = NULL;
652: out:
653: free(authlist);
1.218 markus 654: return 0;
1.51 markus 655: }
1.169 djm 656:
1.287 djm 657: /*
658: * Format an identity for logging including filename, key type, fingerprint
659: * and location (agent, etc.). Caller must free.
660: */
661: static char *
662: format_identity(Identity *id)
663: {
664: char *fp = NULL, *ret = NULL;
1.309 djm 665: const char *note = "";
1.287 djm 666:
667: if (id->key != NULL) {
668: fp = sshkey_fingerprint(id->key, options.fingerprint_hash,
669: SSH_FP_DEFAULT);
670: }
1.309 djm 671: if (id->key) {
672: if ((id->key->flags & SSHKEY_FLAG_EXT) != 0)
673: note = " token";
1.311 markus 674: else if (sshkey_is_sk(id->key))
1.319 naddy 675: note = " authenticator";
1.309 djm 676: }
1.287 djm 677: xasprintf(&ret, "%s %s%s%s%s%s%s",
678: id->filename,
679: id->key ? sshkey_type(id->key) : "", id->key ? " " : "",
680: fp ? fp : "",
1.309 djm 681: id->userprovided ? " explicit" : "", note,
1.287 djm 682: id->agent_fd != -1 ? " agent" : "");
683: free(fp);
684: return ret;
685: }
686:
1.169 djm 687: /* ARGSUSED */
1.302 djm 688: static int
1.261 markus 689: input_userauth_pk_ok(int type, u_int32_t seq, struct ssh *ssh)
1.51 markus 690: {
1.260 markus 691: Authctxt *authctxt = ssh->authctxt;
1.259 markus 692: struct sshkey *key = NULL;
1.117 markus 693: Identity *id = NULL;
1.287 djm 694: int pktype, found = 0, sent = 0;
1.278 markus 695: size_t blen;
1.287 djm 696: char *pkalg = NULL, *fp = NULL, *ident = NULL;
1.278 markus 697: u_char *pkblob = NULL;
698: int r;
1.51 markus 699:
700: if (authctxt == NULL)
701: fatal("input_userauth_pk_ok: no authentication context");
1.267 djm 702:
1.278 markus 703: if ((r = sshpkt_get_cstring(ssh, &pkalg, NULL)) != 0 ||
704: (r = sshpkt_get_string(ssh, &pkblob, &blen)) != 0 ||
705: (r = sshpkt_get_end(ssh)) != 0)
706: goto done;
1.51 markus 707:
1.278 markus 708: if ((pktype = sshkey_type_from_name(pkalg)) == KEY_UNSPEC) {
1.331 djm 709: debug_f("server sent unknown pkalg %s", pkalg);
1.117 markus 710: goto done;
711: }
1.278 markus 712: if ((r = sshkey_from_blob(pkblob, blen, &key)) != 0) {
1.331 djm 713: debug_r(r, "no key from blob. pkalg %s", pkalg);
1.117 markus 714: goto done;
715: }
716: if (key->type != pktype) {
717: error("input_userauth_pk_ok: type mismatch "
718: "for decoded key (received %d, expected %d)",
719: key->type, pktype);
720: goto done;
721: }
722:
1.127 markus 723: /*
724: * search keys in the reverse order, because last candidate has been
725: * moved to the end of the queue. this also avoids confusion by
726: * duplicate keys
727: */
1.136 henning 728: TAILQ_FOREACH_REVERSE(id, &authctxt->keys, idlist, next) {
1.278 markus 729: if (sshkey_equal(key, id->key)) {
1.287 djm 730: found = 1;
1.51 markus 731: break;
732: }
1.117 markus 733: }
1.287 djm 734: if (!found || id == NULL) {
735: fp = sshkey_fingerprint(key, options.fingerprint_hash,
736: SSH_FP_DEFAULT);
1.331 djm 737: error_f("server replied with unknown key: %s %s",
1.287 djm 738: sshkey_type(key), fp == NULL ? "<ERROR>" : fp);
739: goto done;
740: }
741: ident = format_identity(id);
742: debug("Server accepts key: %s", ident);
1.295 djm 743: sent = sign_and_send_pubkey(ssh, id);
1.278 markus 744: r = 0;
745: done:
746: sshkey_free(key);
1.287 djm 747: free(ident);
748: free(fp);
1.197 djm 749: free(pkalg);
750: free(pkblob);
1.51 markus 751:
1.106 deraadt 752: /* try another method if we did not send a packet */
1.278 markus 753: if (r == 0 && sent == 0)
1.295 djm 754: userauth(ssh, NULL);
1.278 markus 755: return r;
1.20 markus 756: }
1.121 markus 757:
758: #ifdef GSSAPI
1.302 djm 759: static int
1.295 djm 760: userauth_gssapi(struct ssh *ssh)
1.121 markus 761: {
1.295 djm 762: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.121 markus 763: Gssctxt *gssctxt = NULL;
764: OM_uint32 min;
1.278 markus 765: int r, ok = 0;
1.302 djm 766: gss_OID mech = NULL;
1.121 markus 767:
768: /* Try one GSSAPI method at a time, rather than sending them all at
769: * once. */
770:
1.302 djm 771: if (authctxt->gss_supported_mechs == NULL)
772: gss_indicate_mechs(&min, &authctxt->gss_supported_mechs);
1.121 markus 773:
1.302 djm 774: /* Check to see whether the mechanism is usable before we offer it */
775: while (authctxt->mech_tried < authctxt->gss_supported_mechs->count &&
776: !ok) {
777: mech = &authctxt->gss_supported_mechs->
778: elements[authctxt->mech_tried];
1.121 markus 779: /* My DER encoding requires length<128 */
1.302 djm 780: if (mech->length < 128 && ssh_gssapi_check_mechanism(&gssctxt,
781: mech, authctxt->host)) {
1.121 markus 782: ok = 1; /* Mechanism works */
783: } else {
1.302 djm 784: authctxt->mech_tried++;
1.121 markus 785: }
786: }
787:
1.302 djm 788: if (!ok || mech == NULL)
1.139 djm 789: return 0;
1.121 markus 790:
791: authctxt->methoddata=(void *)gssctxt;
792:
1.278 markus 793: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
794: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
795: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
796: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
797: (r = sshpkt_put_u32(ssh, 1)) != 0 ||
1.302 djm 798: (r = sshpkt_put_u32(ssh, (mech->length) + 2)) != 0 ||
1.278 markus 799: (r = sshpkt_put_u8(ssh, SSH_GSS_OIDTYPE)) != 0 ||
1.302 djm 800: (r = sshpkt_put_u8(ssh, mech->length)) != 0 ||
801: (r = sshpkt_put(ssh, mech->elements, mech->length)) != 0 ||
1.278 markus 802: (r = sshpkt_send(ssh)) != 0)
1.331 djm 803: fatal_fr(r, "send packet");
1.278 markus 804:
805: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_RESPONSE, &input_gssapi_response);
806: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_TOKEN, &input_gssapi_token);
807: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_ERROR, &input_gssapi_error);
808: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_GSSAPI_ERRTOK, &input_gssapi_errtok);
1.121 markus 809:
1.302 djm 810: authctxt->mech_tried++; /* Move along to next candidate */
1.121 markus 811:
812: return 1;
813: }
814:
1.302 djm 815: static void
816: userauth_gssapi_cleanup(struct ssh *ssh)
817: {
818: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
819: Gssctxt *gssctxt = (Gssctxt *)authctxt->methoddata;
820:
821: ssh_gssapi_delete_ctx(&gssctxt);
822: authctxt->methoddata = NULL;
823:
824: free(authctxt->gss_supported_mechs);
825: authctxt->gss_supported_mechs = NULL;
826: }
827:
1.130 markus 828: static OM_uint32
1.262 djm 829: process_gssapi_token(struct ssh *ssh, gss_buffer_t recv_tok)
1.130 markus 830: {
1.260 markus 831: Authctxt *authctxt = ssh->authctxt;
1.130 markus 832: Gssctxt *gssctxt = authctxt->methoddata;
833: gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
1.142 djm 834: gss_buffer_desc mic = GSS_C_EMPTY_BUFFER;
835: gss_buffer_desc gssbuf;
1.132 markus 836: OM_uint32 status, ms, flags;
1.278 markus 837: int r;
1.133 djm 838:
1.130 markus 839: status = ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
1.132 markus 840: recv_tok, &send_tok, &flags);
1.130 markus 841:
842: if (send_tok.length > 0) {
1.278 markus 843: u_char type = GSS_ERROR(status) ?
844: SSH2_MSG_USERAUTH_GSSAPI_ERRTOK :
845: SSH2_MSG_USERAUTH_GSSAPI_TOKEN;
846:
847: if ((r = sshpkt_start(ssh, type)) != 0 ||
848: (r = sshpkt_put_string(ssh, send_tok.value,
849: send_tok.length)) != 0 ||
850: (r = sshpkt_send(ssh)) != 0)
1.331 djm 851: fatal_fr(r, "send %u packet", type);
1.133 djm 852:
1.130 markus 853: gss_release_buffer(&ms, &send_tok);
854: }
1.133 djm 855:
1.130 markus 856: if (status == GSS_S_COMPLETE) {
1.132 markus 857: /* send either complete or MIC, depending on mechanism */
858: if (!(flags & GSS_C_INTEG_FLAG)) {
1.278 markus 859: if ((r = sshpkt_start(ssh,
860: SSH2_MSG_USERAUTH_GSSAPI_EXCHANGE_COMPLETE)) != 0 ||
861: (r = sshpkt_send(ssh)) != 0)
1.331 djm 862: fatal_fr(r, "send completion");
1.132 markus 863: } else {
1.278 markus 864: struct sshbuf *b;
865:
866: if ((b = sshbuf_new()) == NULL)
1.331 djm 867: fatal_f("sshbuf_new failed");
1.278 markus 868: ssh_gssapi_buildmic(b, authctxt->server_user,
1.132 markus 869: authctxt->service, "gssapi-with-mic");
870:
1.278 markus 871: if ((gssbuf.value = sshbuf_mutable_ptr(b)) == NULL)
1.331 djm 872: fatal_f("sshbuf_mutable_ptr failed");
1.278 markus 873: gssbuf.length = sshbuf_len(b);
1.133 djm 874:
1.132 markus 875: status = ssh_gssapi_sign(gssctxt, &gssbuf, &mic);
1.133 djm 876:
1.132 markus 877: if (!GSS_ERROR(status)) {
1.278 markus 878: if ((r = sshpkt_start(ssh,
879: SSH2_MSG_USERAUTH_GSSAPI_MIC)) != 0 ||
880: (r = sshpkt_put_string(ssh, mic.value,
881: mic.length)) != 0 ||
882: (r = sshpkt_send(ssh)) != 0)
1.331 djm 883: fatal_fr(r, "send MIC");
1.132 markus 884: }
1.133 djm 885:
1.278 markus 886: sshbuf_free(b);
1.132 markus 887: gss_release_buffer(&ms, &mic);
1.133 djm 888: }
1.130 markus 889: }
1.133 djm 890:
1.130 markus 891: return status;
892: }
893:
1.169 djm 894: /* ARGSUSED */
1.302 djm 895: static int
1.261 markus 896: input_gssapi_response(int type, u_int32_t plen, struct ssh *ssh)
1.121 markus 897: {
1.260 markus 898: Authctxt *authctxt = ssh->authctxt;
1.121 markus 899: Gssctxt *gssctxt;
1.278 markus 900: size_t oidlen;
901: u_char *oidv = NULL;
902: int r;
1.121 markus 903:
904: if (authctxt == NULL)
905: fatal("input_gssapi_response: no authentication context");
906: gssctxt = authctxt->methoddata;
907:
908: /* Setup our OID */
1.278 markus 909: if ((r = sshpkt_get_string(ssh, &oidv, &oidlen)) != 0)
910: goto done;
1.121 markus 911:
1.129 markus 912: if (oidlen <= 2 ||
913: oidv[0] != SSH_GSS_OIDTYPE ||
914: oidv[1] != oidlen - 2) {
915: debug("Badly encoded mechanism OID received");
1.296 djm 916: userauth(ssh, NULL);
1.278 markus 917: goto ok;
1.121 markus 918: }
1.129 markus 919:
920: if (!ssh_gssapi_check_oid(gssctxt, oidv + 2, oidlen - 2))
921: fatal("Server returned different OID than expected");
1.121 markus 922:
1.278 markus 923: if ((r = sshpkt_get_end(ssh)) != 0)
924: goto done;
1.121 markus 925:
1.262 djm 926: if (GSS_ERROR(process_gssapi_token(ssh, GSS_C_NO_BUFFER))) {
1.121 markus 927: /* Start again with next method on list */
928: debug("Trying to start again");
1.296 djm 929: userauth(ssh, NULL);
1.278 markus 930: goto ok;
1.121 markus 931: }
1.278 markus 932: ok:
933: r = 0;
934: done:
935: free(oidv);
936: return r;
1.121 markus 937: }
938:
1.169 djm 939: /* ARGSUSED */
1.302 djm 940: static int
1.261 markus 941: input_gssapi_token(int type, u_int32_t plen, struct ssh *ssh)
1.121 markus 942: {
1.260 markus 943: Authctxt *authctxt = ssh->authctxt;
1.121 markus 944: gss_buffer_desc recv_tok;
1.278 markus 945: u_char *p = NULL;
946: size_t len;
1.130 markus 947: OM_uint32 status;
1.278 markus 948: int r;
1.121 markus 949:
950: if (authctxt == NULL)
951: fatal("input_gssapi_response: no authentication context");
952:
1.278 markus 953: if ((r = sshpkt_get_string(ssh, &p, &len)) != 0 ||
954: (r = sshpkt_get_end(ssh)) != 0)
955: goto out;
1.121 markus 956:
1.278 markus 957: recv_tok.value = p;
958: recv_tok.length = len;
1.262 djm 959: status = process_gssapi_token(ssh, &recv_tok);
1.121 markus 960:
1.278 markus 961: /* Start again with the next method in the list */
1.121 markus 962: if (GSS_ERROR(status)) {
1.296 djm 963: userauth(ssh, NULL);
1.278 markus 964: /* ok */
1.121 markus 965: }
1.278 markus 966: r = 0;
967: out:
968: free(p);
969: return r;
1.121 markus 970: }
971:
1.169 djm 972: /* ARGSUSED */
1.302 djm 973: static int
1.261 markus 974: input_gssapi_errtok(int type, u_int32_t plen, struct ssh *ssh)
1.121 markus 975: {
1.260 markus 976: Authctxt *authctxt = ssh->authctxt;
1.121 markus 977: Gssctxt *gssctxt;
978: gss_buffer_desc send_tok = GSS_C_EMPTY_BUFFER;
979: gss_buffer_desc recv_tok;
1.194 djm 980: OM_uint32 ms;
1.278 markus 981: u_char *p = NULL;
982: size_t len;
983: int r;
1.121 markus 984:
985: if (authctxt == NULL)
986: fatal("input_gssapi_response: no authentication context");
987: gssctxt = authctxt->methoddata;
988:
1.278 markus 989: if ((r = sshpkt_get_string(ssh, &p, &len)) != 0 ||
990: (r = sshpkt_get_end(ssh)) != 0) {
991: free(p);
992: return r;
993: }
1.121 markus 994:
995: /* Stick it into GSSAPI and see what it says */
1.278 markus 996: recv_tok.value = p;
997: recv_tok.length = len;
1.194 djm 998: (void)ssh_gssapi_init_ctx(gssctxt, options.gss_deleg_creds,
1.140 djm 999: &recv_tok, &send_tok, NULL);
1.278 markus 1000: free(p);
1.121 markus 1001: gss_release_buffer(&ms, &send_tok);
1002:
1003: /* Server will be returning a failed packet after this one */
1.220 djm 1004: return 0;
1.121 markus 1005: }
1006:
1.169 djm 1007: /* ARGSUSED */
1.302 djm 1008: static int
1.261 markus 1009: input_gssapi_error(int type, u_int32_t plen, struct ssh *ssh)
1.121 markus 1010: {
1.278 markus 1011: char *msg = NULL;
1012: char *lang = NULL;
1013: int r;
1.121 markus 1014:
1.278 markus 1015: if ((r = sshpkt_get_u32(ssh, NULL)) != 0 || /* maj */
1016: (r = sshpkt_get_u32(ssh, NULL)) != 0 || /* min */
1017: (r = sshpkt_get_cstring(ssh, &msg, NULL)) != 0 ||
1018: (r = sshpkt_get_cstring(ssh, &lang, NULL)) != 0)
1019: goto out;
1020: r = sshpkt_get_end(ssh);
1.143 stevesk 1021: debug("Server GSSAPI Error:\n%s", msg);
1.278 markus 1022: out:
1.197 djm 1023: free(msg);
1024: free(lang);
1.278 markus 1025: return r;
1.121 markus 1026: }
1027: #endif /* GSSAPI */
1.20 markus 1028:
1.302 djm 1029: static int
1.295 djm 1030: userauth_none(struct ssh *ssh)
1.23 markus 1031: {
1.295 djm 1032: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.278 markus 1033: int r;
1034:
1.23 markus 1035: /* initial userauth request */
1.278 markus 1036: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1037: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1038: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1039: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1040: (r = sshpkt_send(ssh)) != 0)
1.331 djm 1041: fatal_fr(r, "send packet");
1.23 markus 1042: return 1;
1043: }
1044:
1.302 djm 1045: static int
1.295 djm 1046: userauth_passwd(struct ssh *ssh)
1.1 markus 1047: {
1.295 djm 1048: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.290 djm 1049: char *password, *prompt = NULL;
1.175 dtucker 1050: const char *host = options.host_key_alias ? options.host_key_alias :
1051: authctxt->host;
1.278 markus 1052: int r;
1.6 markus 1053:
1.292 djm 1054: if (authctxt->attempt_passwd++ >= options.number_of_password_prompts)
1.6 markus 1055: return 0;
1.13 todd 1056:
1.292 djm 1057: if (authctxt->attempt_passwd != 1)
1.13 todd 1058: error("Permission denied, please try again.");
1.1 markus 1059:
1.290 djm 1060: xasprintf(&prompt, "%s@%s's password: ", authctxt->server_user, host);
1.1 markus 1061: password = read_passphrase(prompt, 0);
1.278 markus 1062: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1063: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1064: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1065: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1066: (r = sshpkt_put_u8(ssh, 0)) != 0 ||
1067: (r = sshpkt_put_cstring(ssh, password)) != 0 ||
1068: (r = sshpkt_add_padding(ssh, 64)) != 0 ||
1069: (r = sshpkt_send(ssh)) != 0)
1.331 djm 1070: fatal_fr(r, "send packet");
1.99 markus 1071:
1.290 djm 1072: free(prompt);
1073: if (password != NULL)
1.278 markus 1074: freezero(password, strlen(password));
1075:
1076: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
1.99 markus 1077: &input_userauth_passwd_changereq);
1078:
1.1 markus 1079: return 1;
1080: }
1.169 djm 1081:
1.99 markus 1082: /*
1083: * parse PASSWD_CHANGEREQ, prompt user and send SSH2_MSG_USERAUTH_REQUEST
1084: */
1.169 djm 1085: /* ARGSUSED */
1.302 djm 1086: static int
1.261 markus 1087: input_userauth_passwd_changereq(int type, u_int32_t seqnr, struct ssh *ssh)
1.99 markus 1088: {
1.260 markus 1089: Authctxt *authctxt = ssh->authctxt;
1.278 markus 1090: char *info = NULL, *lang = NULL, *password = NULL, *retype = NULL;
1.266 dtucker 1091: char prompt[256];
1.252 djm 1092: const char *host;
1.278 markus 1093: int r;
1.99 markus 1094:
1095: debug2("input_userauth_passwd_changereq");
1096:
1097: if (authctxt == NULL)
1098: fatal("input_userauth_passwd_changereq: "
1099: "no authentication context");
1.252 djm 1100: host = options.host_key_alias ? options.host_key_alias : authctxt->host;
1.99 markus 1101:
1.278 markus 1102: if ((r = sshpkt_get_cstring(ssh, &info, NULL)) != 0 ||
1103: (r = sshpkt_get_cstring(ssh, &lang, NULL)) != 0)
1104: goto out;
1.99 markus 1105: if (strlen(info) > 0)
1.116 itojun 1106: logit("%s", info);
1.278 markus 1107: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1108: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1109: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1110: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1111: (r = sshpkt_put_u8(ssh, 1)) != 0) /* additional info */
1112: goto out;
1113:
1.104 deraadt 1114: snprintf(prompt, sizeof(prompt),
1.99 markus 1115: "Enter %.30s@%.128s's old password: ",
1.175 dtucker 1116: authctxt->server_user, host);
1.99 markus 1117: password = read_passphrase(prompt, 0);
1.278 markus 1118: if ((r = sshpkt_put_cstring(ssh, password)) != 0)
1119: goto out;
1120:
1121: freezero(password, strlen(password));
1.99 markus 1122: password = NULL;
1123: while (password == NULL) {
1.104 deraadt 1124: snprintf(prompt, sizeof(prompt),
1.99 markus 1125: "Enter %.30s@%.128s's new password: ",
1.175 dtucker 1126: authctxt->server_user, host);
1.99 markus 1127: password = read_passphrase(prompt, RP_ALLOW_EOF);
1128: if (password == NULL) {
1129: /* bail out */
1.278 markus 1130: r = 0;
1131: goto out;
1.99 markus 1132: }
1.104 deraadt 1133: snprintf(prompt, sizeof(prompt),
1.99 markus 1134: "Retype %.30s@%.128s's new password: ",
1.175 dtucker 1135: authctxt->server_user, host);
1.99 markus 1136: retype = read_passphrase(prompt, 0);
1137: if (strcmp(password, retype) != 0) {
1.278 markus 1138: freezero(password, strlen(password));
1.116 itojun 1139: logit("Mismatch; try again, EOF to quit.");
1.99 markus 1140: password = NULL;
1141: }
1.278 markus 1142: freezero(retype, strlen(retype));
1.99 markus 1143: }
1.278 markus 1144: if ((r = sshpkt_put_cstring(ssh, password)) != 0 ||
1145: (r = sshpkt_add_padding(ssh, 64)) != 0 ||
1146: (r = sshpkt_send(ssh)) != 0)
1147: goto out;
1.104 deraadt 1148:
1.278 markus 1149: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_PASSWD_CHANGEREQ,
1.99 markus 1150: &input_userauth_passwd_changereq);
1.278 markus 1151: r = 0;
1152: out:
1153: if (password)
1154: freezero(password, strlen(password));
1155: free(info);
1156: free(lang);
1157: return r;
1.117 markus 1158: }
1159:
1.272 djm 1160: /*
1161: * Select an algorithm for publickey signatures.
1162: * Returns algorithm (caller must free) or NULL if no mutual algorithm found.
1163: *
1164: * Call with ssh==NULL to ignore server-sig-algs extension list and
1165: * only attempt with the key's base signature type.
1166: */
1167: static char *
1168: key_sig_algorithm(struct ssh *ssh, const struct sshkey *key)
1.231 markus 1169: {
1.274 djm 1170: char *allowed, *oallowed, *cp, *tmp, *alg = NULL;
1.231 markus 1171:
1.272 djm 1172: /*
1173: * The signature algorithm will only differ from the key algorithm
1174: * for RSA keys/certs and when the server advertises support for
1175: * newer (SHA2) algorithms.
1176: */
1177: if (ssh == NULL || ssh->kex->server_sig_algs == NULL ||
1.288 djm 1178: (key->type != KEY_RSA && key->type != KEY_RSA_CERT) ||
1179: (key->type == KEY_RSA_CERT && (datafellows & SSH_BUG_SIGTYPE))) {
1.272 djm 1180: /* Filter base key signature alg against our configuration */
1.279 markus 1181: return match_list(sshkey_ssh_name(key),
1.272 djm 1182: options.pubkey_key_types, NULL);
1.231 markus 1183: }
1184:
1.272 djm 1185: /*
1186: * For RSA keys/certs, since these might have a different sig type:
1187: * find the first entry in PubkeyAcceptedKeyTypes of the right type
1188: * that also appears in the supported signature algorithms list from
1189: * the server.
1190: */
1191: oallowed = allowed = xstrdup(options.pubkey_key_types);
1192: while ((cp = strsep(&allowed, ",")) != NULL) {
1193: if (sshkey_type_from_name(cp) != key->type)
1194: continue;
1.323 djm 1195: tmp = match_list(sshkey_sigalg_by_name(cp),
1196: ssh->kex->server_sig_algs, NULL);
1.274 djm 1197: if (tmp != NULL)
1198: alg = xstrdup(cp);
1199: free(tmp);
1.272 djm 1200: if (alg != NULL)
1201: break;
1.269 djm 1202: }
1.272 djm 1203: free(oallowed);
1204: return alg;
1.269 djm 1205: }
1206:
1.117 markus 1207: static int
1.214 djm 1208: identity_sign(struct identity *id, u_char **sigp, size_t *lenp,
1.272 djm 1209: const u_char *data, size_t datalen, u_int compat, const char *alg)
1.117 markus 1210: {
1.309 djm 1211: struct sshkey *sign_key = NULL, *prv = NULL;
1212: int r = SSH_ERR_INTERNAL_ERROR;
1.312 djm 1213: struct notifier_ctx *notifier = NULL;
1.325 djm 1214: char *fp = NULL, *pin = NULL, *prompt = NULL;
1.309 djm 1215:
1216: *sigp = NULL;
1217: *lenp = 0;
1.99 markus 1218:
1.272 djm 1219: /* The agent supports this key. */
1.269 djm 1220: if (id->key != NULL && id->agent_fd != -1) {
1.272 djm 1221: return ssh_agent_sign(id->agent_fd, id->key, sigp, lenp,
1222: data, datalen, alg, compat);
1.269 djm 1223: }
1.214 djm 1224:
1.117 markus 1225: /*
1.272 djm 1226: * We have already loaded the private key or the private key is
1227: * stored in external hardware.
1.117 markus 1228: */
1.255 djm 1229: if (id->key != NULL &&
1.272 djm 1230: (id->isprivate || (id->key->flags & SSHKEY_FLAG_EXT))) {
1.309 djm 1231: sign_key = id->key;
1232: } else {
1233: /* Load the private key from the file. */
1234: if ((prv = load_identity_file(id)) == NULL)
1235: return SSH_ERR_KEY_NOT_FOUND;
1236: if (id->key != NULL && !sshkey_equal_public(prv, id->key)) {
1.331 djm 1237: error_f("private key %s contents do not match public",
1238: id->filename);
1.309 djm 1239: r = SSH_ERR_KEY_NOT_FOUND;
1240: goto out;
1241: }
1242: sign_key = prv;
1.325 djm 1243: if (sshkey_is_sk(sign_key)) {
1244: if ((sign_key->sk_flags &
1245: SSH_SK_USER_VERIFICATION_REQD)) {
1246: xasprintf(&prompt, "Enter PIN for %s key %s: ",
1247: sshkey_type(sign_key), id->filename);
1248: pin = read_passphrase(prompt, 0);
1249: }
1250: if ((sign_key->sk_flags & SSH_SK_USER_PRESENCE_REQD)) {
1251: /* XXX should batch mode just skip these? */
1252: if ((fp = sshkey_fingerprint(sign_key,
1253: options.fingerprint_hash,
1254: SSH_FP_DEFAULT)) == NULL)
1.331 djm 1255: fatal_f("fingerprint failed");
1.325 djm 1256: notifier = notify_start(options.batch_mode,
1257: "Confirm user presence for key %s %s",
1258: sshkey_type(sign_key), fp);
1259: free(fp);
1260: }
1.312 djm 1261: }
1.272 djm 1262: }
1.310 djm 1263: if ((r = sshkey_sign(sign_key, sigp, lenp, data, datalen,
1.325 djm 1264: alg, options.sk_provider, pin, compat)) != 0) {
1.331 djm 1265: debug_fr(r, "sshkey_sign");
1.309 djm 1266: goto out;
1267: }
1268: /*
1269: * PKCS#11 tokens may not support all signature algorithms,
1270: * so check what we get back.
1271: */
1272: if ((r = sshkey_check_sigtype(*sigp, *lenp, alg)) != 0) {
1.331 djm 1273: debug_fr(r, "sshkey_check_sigtype");
1.309 djm 1274: goto out;
1.265 djm 1275: }
1.309 djm 1276: /* success */
1277: r = 0;
1278: out:
1.325 djm 1279: free(prompt);
1280: if (pin != NULL)
1281: freezero(pin, strlen(pin));
1.334 djm 1282: notify_complete(notifier, "User presence confirmed");
1.214 djm 1283: sshkey_free(prv);
1.269 djm 1284: return r;
1.51 markus 1285: }
1286:
1.76 itojun 1287: static int
1.255 djm 1288: id_filename_matches(Identity *id, Identity *private_id)
1289: {
1290: const char *suffixes[] = { ".pub", "-cert.pub", NULL };
1291: size_t len = strlen(id->filename), plen = strlen(private_id->filename);
1292: size_t i, slen;
1293:
1294: if (strcmp(id->filename, private_id->filename) == 0)
1295: return 1;
1296: for (i = 0; suffixes[i]; i++) {
1297: slen = strlen(suffixes[i]);
1298: if (len > slen && plen == len - slen &&
1299: strcmp(id->filename + (len - slen), suffixes[i]) == 0 &&
1300: memcmp(id->filename, private_id->filename, plen) == 0)
1301: return 1;
1302: }
1303: return 0;
1304: }
1305:
1306: static int
1.295 djm 1307: sign_and_send_pubkey(struct ssh *ssh, Identity *id)
1.1 markus 1308: {
1.295 djm 1309: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.272 djm 1310: struct sshbuf *b = NULL;
1311: Identity *private_id, *sign_id = NULL;
1312: u_char *signature = NULL;
1313: size_t slen = 0, skip = 0;
1314: int r, fallback_sigtype, sent = 0;
1315: char *alg = NULL, *fp = NULL;
1316: const char *loc = "";
1.1 markus 1317:
1.222 djm 1318: if ((fp = sshkey_fingerprint(id->key, options.fingerprint_hash,
1319: SSH_FP_DEFAULT)) == NULL)
1320: return 0;
1.51 markus 1321:
1.331 djm 1322: debug3_f("%s %s", sshkey_type(id->key), fp);
1.1 markus 1323:
1.227 djm 1324: /*
1325: * If the key is an certificate, try to find a matching private key
1326: * and use it to complete the signature.
1.241 djm 1327: * If no such private key exists, fall back to trying the certificate
1328: * key itself in case it has a private half already loaded.
1.272 djm 1329: * This will try to set sign_id to the private key that will perform
1330: * the signature.
1.227 djm 1331: */
1.272 djm 1332: if (sshkey_is_cert(id->key)) {
1.227 djm 1333: TAILQ_FOREACH(private_id, &authctxt->keys, next) {
1334: if (sshkey_equal_public(id->key, private_id->key) &&
1335: id->key->type != private_id->key->type) {
1.272 djm 1336: sign_id = private_id;
1.227 djm 1337: break;
1338: }
1339: }
1.255 djm 1340: /*
1341: * Exact key matches are preferred, but also allow
1342: * filename matches for non-PKCS#11/agent keys that
1343: * didn't load public keys. This supports the case
1344: * of keeping just a private key file and public
1345: * certificate on disk.
1346: */
1.272 djm 1347: if (sign_id == NULL &&
1348: !id->isprivate && id->agent_fd == -1 &&
1.255 djm 1349: (id->key->flags & SSHKEY_FLAG_EXT) == 0) {
1350: TAILQ_FOREACH(private_id, &authctxt->keys, next) {
1351: if (private_id->key == NULL &&
1352: id_filename_matches(id, private_id)) {
1.272 djm 1353: sign_id = private_id;
1.255 djm 1354: break;
1355: }
1356: }
1357: }
1.272 djm 1358: if (sign_id != NULL) {
1.331 djm 1359: debug2_f("using private key \"%s\"%s for "
1360: "certificate", id->filename,
1.227 djm 1361: id->agent_fd != -1 ? " from agent" : "");
1362: } else {
1.331 djm 1363: debug_f("no separate private key for certificate "
1364: "\"%s\"", id->filename);
1.227 djm 1365: }
1366: }
1367:
1.272 djm 1368: /*
1369: * If the above didn't select another identity to do the signing
1370: * then default to the one we started with.
1371: */
1372: if (sign_id == NULL)
1373: sign_id = id;
1374:
1375: /* assemble and sign data */
1376: for (fallback_sigtype = 0; fallback_sigtype <= 1; fallback_sigtype++) {
1377: free(alg);
1378: slen = 0;
1379: signature = NULL;
1380: if ((alg = key_sig_algorithm(fallback_sigtype ? NULL : ssh,
1381: id->key)) == NULL) {
1.331 djm 1382: error_f("no mutual signature supported");
1.272 djm 1383: goto out;
1384: }
1.331 djm 1385: debug3_f("signing using %s %s", alg, fp);
1.272 djm 1386:
1387: sshbuf_free(b);
1388: if ((b = sshbuf_new()) == NULL)
1.331 djm 1389: fatal_f("sshbuf_new failed");
1.272 djm 1390: if (datafellows & SSH_OLD_SESSIONID) {
1391: if ((r = sshbuf_put(b, session_id2,
1.331 djm 1392: session_id2_len)) != 0)
1393: fatal_fr(r, "sshbuf_put");
1.272 djm 1394: } else {
1395: if ((r = sshbuf_put_string(b, session_id2,
1.331 djm 1396: session_id2_len)) != 0)
1397: fatal_fr(r, "sshbuf_put_string");
1.272 djm 1398: }
1.278 markus 1399: skip = sshbuf_len(b);
1.272 djm 1400: if ((r = sshbuf_put_u8(b, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1401: (r = sshbuf_put_cstring(b, authctxt->server_user)) != 0 ||
1402: (r = sshbuf_put_cstring(b, authctxt->service)) != 0 ||
1403: (r = sshbuf_put_cstring(b, authctxt->method->name)) != 0 ||
1404: (r = sshbuf_put_u8(b, 1)) != 0 ||
1405: (r = sshbuf_put_cstring(b, alg)) != 0 ||
1406: (r = sshkey_puts(id->key, b)) != 0) {
1.331 djm 1407: fatal_fr(r, "assemble signed data");
1.272 djm 1408: }
1409:
1410: /* generate signature */
1411: r = identity_sign(sign_id, &signature, &slen,
1412: sshbuf_ptr(b), sshbuf_len(b), datafellows, alg);
1413: if (r == 0)
1414: break;
1415: else if (r == SSH_ERR_KEY_NOT_FOUND)
1416: goto out; /* soft failure */
1417: else if (r == SSH_ERR_SIGN_ALG_UNSUPPORTED &&
1418: !fallback_sigtype) {
1419: if (sign_id->agent_fd != -1)
1420: loc = "agent ";
1421: else if ((sign_id->key->flags & SSHKEY_FLAG_EXT) != 0)
1422: loc = "token ";
1423: logit("%skey %s %s returned incorrect signature type",
1424: loc, sshkey_type(id->key), fp);
1425: continue;
1426: }
1.331 djm 1427: error_fr(r, "signing failed for %s \"%s\"%s",
1.315 djm 1428: sshkey_type(sign_id->key), sign_id->filename,
1.331 djm 1429: id->agent_fd != -1 ? " from agent" : "");
1.272 djm 1430: goto out;
1.17 markus 1431: }
1.272 djm 1432: if (slen == 0 || signature == NULL) /* shouldn't happen */
1.331 djm 1433: fatal_f("no signature");
1.51 markus 1434:
1.1 markus 1435: /* append signature */
1.272 djm 1436: if ((r = sshbuf_put_string(b, signature, slen)) != 0)
1.331 djm 1437: fatal_fr(r, "append signature");
1.1 markus 1438:
1.272 djm 1439: #ifdef DEBUG_PK
1440: sshbuf_dump(b, stderr);
1441: #endif
1.1 markus 1442: /* skip session id and packet type */
1.272 djm 1443: if ((r = sshbuf_consume(b, skip + 1)) != 0)
1.331 djm 1444: fatal_fr(r, "consume");
1.1 markus 1445:
1446: /* put remaining data from buffer into packet */
1.272 djm 1447: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1448: (r = sshpkt_putb(ssh, b)) != 0 ||
1449: (r = sshpkt_send(ssh)) != 0)
1.331 djm 1450: fatal_fr(r, "enqueue request");
1.272 djm 1451:
1452: /* success */
1453: sent = 1;
1.17 markus 1454:
1.272 djm 1455: out:
1456: free(fp);
1457: free(alg);
1458: sshbuf_free(b);
1459: freezero(signature, slen);
1460: return sent;
1.16 markus 1461: }
1462:
1.76 itojun 1463: static int
1.295 djm 1464: send_pubkey_test(struct ssh *ssh, Identity *id)
1.20 markus 1465: {
1.295 djm 1466: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.272 djm 1467: u_char *blob = NULL;
1468: char *alg = NULL;
1.278 markus 1469: size_t bloblen;
1470: u_int have_sig = 0;
1471: int sent = 0, r;
1.20 markus 1472:
1.272 djm 1473: if ((alg = key_sig_algorithm(ssh, id->key)) == NULL) {
1.331 djm 1474: debug_f("no mutual signature algorithm");
1.272 djm 1475: goto out;
1476: }
1.16 markus 1477:
1.278 markus 1478: if ((r = sshkey_to_blob(id->key, &blob, &bloblen)) != 0) {
1.51 markus 1479: /* we cannot handle this key */
1.331 djm 1480: debug3_f("cannot handle key");
1.272 djm 1481: goto out;
1.16 markus 1482: }
1.51 markus 1483: /* register callback for USERAUTH_PK_OK message */
1.278 markus 1484: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_PK_OK, &input_userauth_pk_ok);
1.51 markus 1485:
1.278 markus 1486: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1487: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1488: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1489: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1490: (r = sshpkt_put_u8(ssh, have_sig)) != 0 ||
1491: (r = sshpkt_put_cstring(ssh, alg)) != 0 ||
1492: (r = sshpkt_put_string(ssh, blob, bloblen)) != 0 ||
1493: (r = sshpkt_send(ssh)) != 0)
1.331 djm 1494: fatal_fr(r, "send packet");
1.272 djm 1495: sent = 1;
1.278 markus 1496:
1497: out:
1.272 djm 1498: free(alg);
1.197 djm 1499: free(blob);
1.272 djm 1500: return sent;
1.51 markus 1501: }
1502:
1.259 markus 1503: static struct sshkey *
1.229 jcs 1504: load_identity_file(Identity *id)
1.51 markus 1505: {
1.259 markus 1506: struct sshkey *private = NULL;
1.229 jcs 1507: char prompt[300], *passphrase, *comment;
1.308 dtucker 1508: int r, quit = 0, i;
1.52 markus 1509: struct stat st;
1.16 markus 1510:
1.306 deraadt 1511: if (stat(id->filename, &st) == -1) {
1.330 djm 1512: do_log2(id->userprovided ?
1513: SYSLOG_LEVEL_INFO : SYSLOG_LEVEL_DEBUG3,
1514: "no such identity: %s: %s", id->filename, strerror(errno));
1.52 markus 1515: return NULL;
1516: }
1.214 djm 1517: snprintf(prompt, sizeof prompt,
1.229 jcs 1518: "Enter passphrase for key '%.100s': ", id->filename);
1.214 djm 1519: for (i = 0; i <= options.number_of_password_prompts; i++) {
1520: if (i == 0)
1521: passphrase = "";
1522: else {
1.20 markus 1523: passphrase = read_passphrase(prompt, 0);
1.214 djm 1524: if (*passphrase == '\0') {
1.20 markus 1525: debug2("no passphrase given, try next key");
1.214 djm 1526: free(passphrase);
1527: break;
1528: }
1529: }
1.229 jcs 1530: switch ((r = sshkey_load_private_type(KEY_UNSPEC, id->filename,
1.308 dtucker 1531: passphrase, &private, &comment))) {
1.214 djm 1532: case 0:
1533: break;
1534: case SSH_ERR_KEY_WRONG_PASSPHRASE:
1535: if (options.batch_mode) {
1536: quit = 1;
1537: break;
1538: }
1.215 djm 1539: if (i != 0)
1540: debug2("bad passphrase given, try again...");
1.214 djm 1541: break;
1542: case SSH_ERR_SYSTEM_ERROR:
1543: if (errno == ENOENT) {
1.331 djm 1544: debug2_r(r, "Load key \"%s\"", id->filename);
1.51 markus 1545: quit = 1;
1.214 djm 1546: break;
1.20 markus 1547: }
1.214 djm 1548: /* FALLTHROUGH */
1549: default:
1.331 djm 1550: error_r(r, "Load key \"%s\"", id->filename);
1.214 djm 1551: quit = 1;
1552: break;
1553: }
1.311 markus 1554: if (private != NULL && sshkey_is_sk(private) &&
1.309 djm 1555: options.sk_provider == NULL) {
1.319 naddy 1556: debug("key \"%s\" is an authenticator-hosted key, "
1557: "but no provider specified", id->filename);
1.309 djm 1558: sshkey_free(private);
1559: private = NULL;
1560: quit = 1;
1561: }
1.230 djm 1562: if (!quit && private != NULL && id->agent_fd == -1 &&
1.229 jcs 1563: !(id->key && id->isprivate))
1564: maybe_add_key_to_agent(id->filename, private, comment,
1565: passphrase);
1.278 markus 1566: if (i > 0)
1567: freezero(passphrase, strlen(passphrase));
1.232 mmcc 1568: free(comment);
1.214 djm 1569: if (private != NULL || quit)
1570: break;
1.16 markus 1571: }
1.51 markus 1572: return private;
1573: }
1574:
1.272 djm 1575: static int
1576: key_type_allowed_by_config(struct sshkey *key)
1577: {
1578: if (match_pattern_list(sshkey_ssh_name(key),
1579: options.pubkey_key_types, 0) == 1)
1580: return 1;
1581:
1582: /* RSA keys/certs might be allowed by alternate signature types */
1583: switch (key->type) {
1584: case KEY_RSA:
1585: if (match_pattern_list("rsa-sha2-512",
1586: options.pubkey_key_types, 0) == 1)
1587: return 1;
1588: if (match_pattern_list("rsa-sha2-256",
1589: options.pubkey_key_types, 0) == 1)
1590: return 1;
1591: break;
1592: case KEY_RSA_CERT:
1593: if (match_pattern_list("rsa-sha2-512-cert-v01@openssh.com",
1594: options.pubkey_key_types, 0) == 1)
1595: return 1;
1596: if (match_pattern_list("rsa-sha2-256-cert-v01@openssh.com",
1597: options.pubkey_key_types, 0) == 1)
1598: return 1;
1599: break;
1600: }
1601: return 0;
1602: }
1603:
1604:
1.117 markus 1605: /*
1606: * try keys in the following order:
1.332 djm 1607: * 1. certificates listed in the config file
1608: * 2. other input certificates
1.227 djm 1609: * 3. agent keys that are found in the config file
1610: * 4. other agent keys
1611: * 5. keys that are only listed in the config file
1.117 markus 1612: */
1613: static void
1614: pubkey_prepare(Authctxt *authctxt)
1.51 markus 1615: {
1.214 djm 1616: struct identity *id, *id2, *tmp;
1617: struct idlist agent, files, *preferred;
1618: struct sshkey *key;
1.230 djm 1619: int agent_fd = -1, i, r, found;
1.214 djm 1620: size_t j;
1621: struct ssh_identitylist *idlist;
1.287 djm 1622: char *ident;
1.51 markus 1623:
1.117 markus 1624: TAILQ_INIT(&agent); /* keys from the agent */
1625: TAILQ_INIT(&files); /* keys from the config file */
1626: preferred = &authctxt->keys;
1627: TAILQ_INIT(preferred); /* preferred order of keys */
1628:
1.190 djm 1629: /* list of keys stored in the filesystem and PKCS#11 */
1.117 markus 1630: for (i = 0; i < options.num_identity_files; i++) {
1631: key = options.identity_keys[i];
1.309 djm 1632: if (key && key->cert &&
1633: key->cert->type != SSH2_CERT_TYPE_USER) {
1.331 djm 1634: debug_f("ignoring certificate %s: not a user "
1635: "certificate", options.identity_files[i]);
1.309 djm 1636: continue;
1637: }
1.311 markus 1638: if (key && sshkey_is_sk(key) && options.sk_provider == NULL) {
1.331 djm 1639: debug_f("ignoring authenticator-hosted key %s as no "
1.309 djm 1640: "SecurityKeyProvider has been specified",
1.331 djm 1641: options.identity_files[i]);
1.117 markus 1642: continue;
1.309 djm 1643: }
1.117 markus 1644: options.identity_keys[i] = NULL;
1.150 djm 1645: id = xcalloc(1, sizeof(*id));
1.230 djm 1646: id->agent_fd = -1;
1.117 markus 1647: id->key = key;
1648: id->filename = xstrdup(options.identity_files[i]);
1.192 dtucker 1649: id->userprovided = options.identity_file_userprovided[i];
1.117 markus 1650: TAILQ_INSERT_TAIL(&files, id, next);
1.190 djm 1651: }
1.227 djm 1652: /* list of certificates specified by user */
1653: for (i = 0; i < options.num_certificate_files; i++) {
1654: key = options.certificates[i];
1.278 markus 1655: if (!sshkey_is_cert(key) || key->cert == NULL ||
1.309 djm 1656: key->cert->type != SSH2_CERT_TYPE_USER) {
1.331 djm 1657: debug_f("ignoring certificate %s: not a user "
1658: "certificate", options.identity_files[i]);
1.227 djm 1659: continue;
1.309 djm 1660: }
1.311 markus 1661: if (key && sshkey_is_sk(key) && options.sk_provider == NULL) {
1.331 djm 1662: debug_f("ignoring authenticator-hosted key "
1.319 naddy 1663: "certificate %s as no "
1.309 djm 1664: "SecurityKeyProvider has been specified",
1.331 djm 1665: options.identity_files[i]);
1.309 djm 1666: continue;
1667: }
1.227 djm 1668: id = xcalloc(1, sizeof(*id));
1.230 djm 1669: id->agent_fd = -1;
1.227 djm 1670: id->key = key;
1671: id->filename = xstrdup(options.certificate_files[i]);
1672: id->userprovided = options.certificate_file_userprovided[i];
1673: TAILQ_INSERT_TAIL(preferred, id, next);
1.117 markus 1674: }
1675: /* list of keys supported by the agent */
1.214 djm 1676: if ((r = ssh_get_authentication_socket(&agent_fd)) != 0) {
1677: if (r != SSH_ERR_AGENT_NOT_PRESENT)
1.331 djm 1678: debug_fr(r, "ssh_get_authentication_socket");
1.258 naddy 1679: } else if ((r = ssh_fetch_identitylist(agent_fd, &idlist)) != 0) {
1.214 djm 1680: if (r != SSH_ERR_AGENT_NO_IDENTITIES)
1.331 djm 1681: debug_fr(r, "ssh_fetch_identitylist");
1.237 markus 1682: close(agent_fd);
1.214 djm 1683: } else {
1684: for (j = 0; j < idlist->nkeys; j++) {
1.117 markus 1685: found = 0;
1686: TAILQ_FOREACH(id, &files, next) {
1.214 djm 1687: /*
1688: * agent keys from the config file are
1689: * preferred
1690: */
1691: if (sshkey_equal(idlist->keys[j], id->key)) {
1.117 markus 1692: TAILQ_REMOVE(&files, id, next);
1693: TAILQ_INSERT_TAIL(preferred, id, next);
1.214 djm 1694: id->agent_fd = agent_fd;
1.117 markus 1695: found = 1;
1696: break;
1697: }
1698: }
1.135 markus 1699: if (!found && !options.identities_only) {
1.150 djm 1700: id = xcalloc(1, sizeof(*id));
1.214 djm 1701: /* XXX "steals" key/comment from idlist */
1702: id->key = idlist->keys[j];
1703: id->filename = idlist->comments[j];
1704: idlist->keys[j] = NULL;
1705: idlist->comments[j] = NULL;
1706: id->agent_fd = agent_fd;
1.117 markus 1707: TAILQ_INSERT_TAIL(&agent, id, next);
1708: }
1709: }
1.214 djm 1710: ssh_free_identitylist(idlist);
1.117 markus 1711: /* append remaining agent keys */
1.324 bket 1712: TAILQ_CONCAT(preferred, &agent, next);
1.214 djm 1713: authctxt->agent_fd = agent_fd;
1.244 djm 1714: }
1715: /* Prefer PKCS11 keys that are explicitly listed */
1716: TAILQ_FOREACH_SAFE(id, &files, next, tmp) {
1717: if (id->key == NULL || (id->key->flags & SSHKEY_FLAG_EXT) == 0)
1718: continue;
1719: found = 0;
1720: TAILQ_FOREACH(id2, &files, next) {
1721: if (id2->key == NULL ||
1.321 djm 1722: (id2->key->flags & SSHKEY_FLAG_EXT) != 0)
1.244 djm 1723: continue;
1724: if (sshkey_equal(id->key, id2->key)) {
1725: TAILQ_REMOVE(&files, id, next);
1726: TAILQ_INSERT_TAIL(preferred, id, next);
1727: found = 1;
1728: break;
1729: }
1730: }
1731: /* If IdentitiesOnly set and key not found then don't use it */
1732: if (!found && options.identities_only) {
1733: TAILQ_REMOVE(&files, id, next);
1.278 markus 1734: freezero(id, sizeof(*id));
1.244 djm 1735: }
1.117 markus 1736: }
1737: /* append remaining keys from the config file */
1.324 bket 1738: TAILQ_CONCAT(preferred, &files, next);
1.228 djm 1739: /* finally, filter by PubkeyAcceptedKeyTypes */
1740: TAILQ_FOREACH_SAFE(id, preferred, next, id2) {
1.273 djm 1741: if (id->key != NULL && !key_type_allowed_by_config(id->key)) {
1.228 djm 1742: debug("Skipping %s key %s - "
1743: "not in PubkeyAcceptedKeyTypes",
1744: sshkey_ssh_name(id->key), id->filename);
1745: TAILQ_REMOVE(preferred, id, next);
1746: sshkey_free(id->key);
1747: free(id->filename);
1748: memset(id, 0, sizeof(*id));
1749: continue;
1750: }
1.117 markus 1751: }
1.287 djm 1752: /* List the keys we plan on using */
1753: TAILQ_FOREACH_SAFE(id, preferred, next, id2) {
1754: ident = format_identity(id);
1755: debug("Will attempt key: %s", ident);
1756: free(ident);
1757: }
1.331 djm 1758: debug2_f("done");
1.17 markus 1759: }
1760:
1.117 markus 1761: static void
1.303 djm 1762: pubkey_cleanup(struct ssh *ssh)
1.51 markus 1763: {
1.302 djm 1764: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.117 markus 1765: Identity *id;
1.51 markus 1766:
1.289 djm 1767: if (authctxt->agent_fd != -1) {
1.214 djm 1768: ssh_close_authentication_socket(authctxt->agent_fd);
1.289 djm 1769: authctxt->agent_fd = -1;
1770: }
1.117 markus 1771: for (id = TAILQ_FIRST(&authctxt->keys); id;
1772: id = TAILQ_FIRST(&authctxt->keys)) {
1773: TAILQ_REMOVE(&authctxt->keys, id, next);
1.235 mmcc 1774: sshkey_free(id->key);
1.197 djm 1775: free(id->filename);
1776: free(id);
1.117 markus 1777: }
1.1 markus 1778: }
1779:
1.251 djm 1780: static void
1781: pubkey_reset(Authctxt *authctxt)
1782: {
1783: Identity *id;
1784:
1785: TAILQ_FOREACH(id, &authctxt->keys, next)
1786: id->tried = 0;
1787: }
1788:
1.225 markus 1789: static int
1790: try_identity(Identity *id)
1791: {
1792: if (!id->key)
1793: return (0);
1.279 markus 1794: if (sshkey_type_plain(id->key->type) == KEY_RSA &&
1.225 markus 1795: (datafellows & SSH_BUG_RSASIGMD5) != 0) {
1796: debug("Skipped %s key %s for RSA/MD5 server",
1.279 markus 1797: sshkey_type(id->key), id->filename);
1.225 markus 1798: return (0);
1799: }
1.257 djm 1800: return 1;
1.225 markus 1801: }
1802:
1.302 djm 1803: static int
1.295 djm 1804: userauth_pubkey(struct ssh *ssh)
1.20 markus 1805: {
1.295 djm 1806: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.117 markus 1807: Identity *id;
1.20 markus 1808: int sent = 0;
1.287 djm 1809: char *ident;
1.20 markus 1810:
1.117 markus 1811: while ((id = TAILQ_FIRST(&authctxt->keys))) {
1812: if (id->tried++)
1813: return (0);
1.127 markus 1814: /* move key to the end of the queue */
1.117 markus 1815: TAILQ_REMOVE(&authctxt->keys, id, next);
1816: TAILQ_INSERT_TAIL(&authctxt->keys, id, next);
1817: /*
1818: * send a test message if we have the public key. for
1819: * encrypted keys we cannot do this and have to load the
1820: * private key instead
1821: */
1.200 djm 1822: if (id->key != NULL) {
1.225 markus 1823: if (try_identity(id)) {
1.287 djm 1824: ident = format_identity(id);
1825: debug("Offering public key: %s", ident);
1826: free(ident);
1.295 djm 1827: sent = send_pubkey_test(ssh, id);
1.200 djm 1828: }
1829: } else {
1.117 markus 1830: debug("Trying private key: %s", id->filename);
1.229 jcs 1831: id->key = load_identity_file(id);
1.117 markus 1832: if (id->key != NULL) {
1.225 markus 1833: if (try_identity(id)) {
1834: id->isprivate = 1;
1.295 djm 1835: sent = sign_and_send_pubkey(ssh, id);
1.200 djm 1836: }
1.278 markus 1837: sshkey_free(id->key);
1.117 markus 1838: id->key = NULL;
1.251 djm 1839: id->isprivate = 0;
1.51 markus 1840: }
1841: }
1.117 markus 1842: if (sent)
1843: return (sent);
1.28 markus 1844: }
1.117 markus 1845: return (0);
1.20 markus 1846: }
1847:
1.23 markus 1848: /*
1849: * Send userauth request message specifying keyboard-interactive method.
1850: */
1.302 djm 1851: static int
1.295 djm 1852: userauth_kbdint(struct ssh *ssh)
1.23 markus 1853: {
1.295 djm 1854: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.278 markus 1855: int r;
1.23 markus 1856:
1.292 djm 1857: if (authctxt->attempt_kbdint++ >= options.number_of_password_prompts)
1.23 markus 1858: return 0;
1.82 markus 1859: /* disable if no SSH2_MSG_USERAUTH_INFO_REQUEST has been seen */
1.292 djm 1860: if (authctxt->attempt_kbdint > 1 && !authctxt->info_req_seen) {
1.82 markus 1861: debug3("userauth_kbdint: disable: no info_req_seen");
1.278 markus 1862: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_INFO_REQUEST, NULL);
1.82 markus 1863: return 0;
1864: }
1.23 markus 1865:
1866: debug2("userauth_kbdint");
1.278 markus 1867: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
1868: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
1869: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
1870: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1871: (r = sshpkt_put_cstring(ssh, "")) != 0 || /* lang */
1872: (r = sshpkt_put_cstring(ssh, options.kbd_interactive_devices ?
1873: options.kbd_interactive_devices : "")) != 0 ||
1874: (r = sshpkt_send(ssh)) != 0)
1.331 djm 1875: fatal_fr(r, "send packet");
1.23 markus 1876:
1.278 markus 1877: ssh_dispatch_set(ssh, SSH2_MSG_USERAUTH_INFO_REQUEST, &input_userauth_info_req);
1.23 markus 1878: return 1;
1879: }
1880:
1881: /*
1.46 markus 1882: * parse INFO_REQUEST, prompt user and send INFO_RESPONSE
1.23 markus 1883: */
1.302 djm 1884: static int
1.261 markus 1885: input_userauth_info_req(int type, u_int32_t seq, struct ssh *ssh)
1.23 markus 1886: {
1.260 markus 1887: Authctxt *authctxt = ssh->authctxt;
1.278 markus 1888: char *name = NULL, *inst = NULL, *lang = NULL, *prompt = NULL;
1.335 djm 1889: char *display_prompt = NULL, *response = NULL;
1.278 markus 1890: u_char echo = 0;
1.32 markus 1891: u_int num_prompts, i;
1.278 markus 1892: int r;
1.23 markus 1893:
1.335 djm 1894: debug2_f("entering");
1.23 markus 1895:
1896: if (authctxt == NULL)
1.335 djm 1897: fatal_f("no authentication context");
1.82 markus 1898:
1899: authctxt->info_req_seen = 1;
1.23 markus 1900:
1.278 markus 1901: if ((r = sshpkt_get_cstring(ssh, &name, NULL)) != 0 ||
1902: (r = sshpkt_get_cstring(ssh, &inst, NULL)) != 0 ||
1903: (r = sshpkt_get_cstring(ssh, &lang, NULL)) != 0)
1904: goto out;
1.23 markus 1905: if (strlen(name) > 0)
1.116 itojun 1906: logit("%s", name);
1.23 markus 1907: if (strlen(inst) > 0)
1.116 itojun 1908: logit("%s", inst);
1.23 markus 1909:
1.278 markus 1910: if ((r = sshpkt_get_u32(ssh, &num_prompts)) != 0)
1911: goto out;
1.23 markus 1912: /*
1913: * Begin to build info response packet based on prompts requested.
1914: * We commit to providing the correct number of responses, so if
1915: * further on we run into a problem that prevents this, we have to
1916: * be sure and clean this up and send a correct error response.
1917: */
1.278 markus 1918: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_INFO_RESPONSE)) != 0 ||
1919: (r = sshpkt_put_u32(ssh, num_prompts)) != 0)
1920: goto out;
1.23 markus 1921:
1.335 djm 1922: debug2_f("num_prompts %d", num_prompts);
1.23 markus 1923: for (i = 0; i < num_prompts; i++) {
1.278 markus 1924: if ((r = sshpkt_get_cstring(ssh, &prompt, NULL)) != 0 ||
1925: (r = sshpkt_get_u8(ssh, &echo)) != 0)
1926: goto out;
1.336 djm 1927: if (asmprintf(&display_prompt, INT_MAX, NULL, "(%s@%s) %s",
1.335 djm 1928: authctxt->server_user, options.host_key_alias ?
1.336 djm 1929: options.host_key_alias : authctxt->host, prompt) == -1)
1930: fatal_f("asmprintf failed");
1.335 djm 1931: response = read_passphrase(display_prompt, echo ? RP_ECHO : 0);
1.278 markus 1932: if ((r = sshpkt_put_cstring(ssh, response)) != 0)
1933: goto out;
1934: freezero(response, strlen(response));
1.197 djm 1935: free(prompt);
1.335 djm 1936: free(display_prompt);
1937: display_prompt = response = prompt = NULL;
1.23 markus 1938: }
1.278 markus 1939: /* done with parsing incoming message. */
1940: if ((r = sshpkt_get_end(ssh)) != 0 ||
1941: (r = sshpkt_add_padding(ssh, 64)) != 0)
1942: goto out;
1943: r = sshpkt_send(ssh);
1944: out:
1945: if (response)
1946: freezero(response, strlen(response));
1947: free(prompt);
1.335 djm 1948: free(display_prompt);
1.278 markus 1949: free(name);
1950: free(inst);
1951: free(lang);
1952: return r;
1.68 markus 1953: }
1954:
1.100 markus 1955: static int
1.294 djm 1956: ssh_keysign(struct ssh *ssh, struct sshkey *key, u_char **sigp, size_t *lenp,
1.223 djm 1957: const u_char *data, size_t datalen)
1.100 markus 1958: {
1.223 djm 1959: struct sshbuf *b;
1.101 markus 1960: struct stat st;
1.100 markus 1961: pid_t pid;
1.304 deraadt 1962: int r, to[2], from[2], status;
1.295 djm 1963: int sock = ssh_packet_get_connection_in(ssh);
1.223 djm 1964: u_char rversion = 0, version = 2;
1965: void (*osigchld)(int);
1.100 markus 1966:
1.223 djm 1967: *sigp = NULL;
1968: *lenp = 0;
1.100 markus 1969:
1.306 deraadt 1970: if (stat(_PATH_SSH_KEY_SIGN, &st) == -1) {
1.331 djm 1971: error_f("not installed: %s", strerror(errno));
1.223 djm 1972: return -1;
1973: }
1974: if (fflush(stdout) != 0) {
1.331 djm 1975: error_f("fflush: %s", strerror(errno));
1.101 markus 1976: return -1;
1977: }
1.306 deraadt 1978: if (pipe(to) == -1) {
1.331 djm 1979: error_f("pipe: %s", strerror(errno));
1.100 markus 1980: return -1;
1981: }
1.306 deraadt 1982: if (pipe(from) == -1) {
1.331 djm 1983: error_f("pipe: %s", strerror(errno));
1.100 markus 1984: return -1;
1985: }
1.306 deraadt 1986: if ((pid = fork()) == -1) {
1.331 djm 1987: error_f("fork: %s", strerror(errno));
1.100 markus 1988: return -1;
1989: }
1.317 dtucker 1990: osigchld = ssh_signal(SIGCHLD, SIG_DFL);
1.100 markus 1991: if (pid == 0) {
1992: close(from[0]);
1.306 deraadt 1993: if (dup2(from[1], STDOUT_FILENO) == -1)
1.331 djm 1994: fatal_f("dup2: %s", strerror(errno));
1.100 markus 1995: close(to[1]);
1.306 deraadt 1996: if (dup2(to[0], STDIN_FILENO) == -1)
1.331 djm 1997: fatal_f("dup2: %s", strerror(errno));
1.103 markus 1998: close(from[1]);
1999: close(to[0]);
1.304 deraadt 2000:
1.306 deraadt 2001: if (dup2(sock, STDERR_FILENO + 1) == -1)
1.331 djm 2002: fatal_f("dup2: %s", strerror(errno));
1.304 deraadt 2003: sock = STDERR_FILENO + 1;
2004: fcntl(sock, F_SETFD, 0); /* keep the socket on exec */
1.223 djm 2005: closefrom(sock + 1);
1.304 deraadt 2006:
1.331 djm 2007: debug3_f("[child] pid=%ld, exec %s",
2008: (long)getpid(), _PATH_SSH_KEY_SIGN);
1.233 mmcc 2009: execl(_PATH_SSH_KEY_SIGN, _PATH_SSH_KEY_SIGN, (char *)NULL);
1.331 djm 2010: fatal_f("exec(%s): %s", _PATH_SSH_KEY_SIGN,
1.100 markus 2011: strerror(errno));
2012: }
2013: close(from[1]);
2014: close(to[0]);
1.305 djm 2015: sock = STDERR_FILENO + 1;
1.100 markus 2016:
1.223 djm 2017: if ((b = sshbuf_new()) == NULL)
1.331 djm 2018: fatal_f("sshbuf_new failed");
1.223 djm 2019: /* send # of sock, data to be signed */
1.253 djm 2020: if ((r = sshbuf_put_u32(b, sock)) != 0 ||
1.223 djm 2021: (r = sshbuf_put_string(b, data, datalen)) != 0)
1.331 djm 2022: fatal_fr(r, "buffer error");
1.223 djm 2023: if (ssh_msg_send(to[1], version, b) == -1)
1.331 djm 2024: fatal_f("couldn't send request");
1.223 djm 2025: sshbuf_reset(b);
2026: r = ssh_msg_recv(from[0], b);
1.101 markus 2027: close(from[0]);
2028: close(to[1]);
1.223 djm 2029: if (r < 0) {
1.331 djm 2030: error_f("no reply");
1.223 djm 2031: goto fail;
2032: }
1.101 markus 2033:
1.223 djm 2034: errno = 0;
1.306 deraadt 2035: while (waitpid(pid, &status, 0) == -1) {
1.223 djm 2036: if (errno != EINTR) {
1.331 djm 2037: error_f("waitpid %ld: %s", (long)pid, strerror(errno));
1.223 djm 2038: goto fail;
2039: }
2040: }
2041: if (!WIFEXITED(status)) {
1.331 djm 2042: error_f("exited abnormally");
1.223 djm 2043: goto fail;
2044: }
2045: if (WEXITSTATUS(status) != 0) {
1.331 djm 2046: error_f("exited with status %d", WEXITSTATUS(status));
1.223 djm 2047: goto fail;
2048: }
2049: if ((r = sshbuf_get_u8(b, &rversion)) != 0) {
1.331 djm 2050: error_fr(r, "buffer error");
1.223 djm 2051: goto fail;
2052: }
2053: if (rversion != version) {
1.331 djm 2054: error_f("bad version");
1.223 djm 2055: goto fail;
2056: }
2057: if ((r = sshbuf_get_string(b, sigp, lenp)) != 0) {
1.331 djm 2058: error_fr(r, "buffer error");
1.223 djm 2059: fail:
1.317 dtucker 2060: ssh_signal(SIGCHLD, osigchld);
1.223 djm 2061: sshbuf_free(b);
1.100 markus 2062: return -1;
2063: }
1.317 dtucker 2064: ssh_signal(SIGCHLD, osigchld);
1.223 djm 2065: sshbuf_free(b);
1.100 markus 2066:
2067: return 0;
2068: }
2069:
1.302 djm 2070: static int
1.295 djm 2071: userauth_hostbased(struct ssh *ssh)
1.68 markus 2072: {
1.295 djm 2073: Authctxt *authctxt = (Authctxt *)ssh->authctxt;
1.223 djm 2074: struct sshkey *private = NULL;
2075: struct sshbuf *b = NULL;
2076: u_char *sig = NULL, *keyblob = NULL;
2077: char *fp = NULL, *chost = NULL, *lname = NULL;
2078: size_t siglen = 0, keylen = 0;
2079: int i, r, success = 0;
2080:
2081: if (authctxt->ktypes == NULL) {
2082: authctxt->oktypes = xstrdup(options.hostbased_key_types);
2083: authctxt->ktypes = authctxt->oktypes;
2084: }
1.213 djm 2085:
1.223 djm 2086: /*
2087: * Work through each listed type pattern in HostbasedKeyTypes,
2088: * trying each hostkey that matches the type in turn.
2089: */
2090: for (;;) {
2091: if (authctxt->active_ktype == NULL)
2092: authctxt->active_ktype = strsep(&authctxt->ktypes, ",");
2093: if (authctxt->active_ktype == NULL ||
2094: *authctxt->active_ktype == '\0')
2095: break;
1.331 djm 2096: debug3_f("trying key type %s", authctxt->active_ktype);
1.68 markus 2097:
1.223 djm 2098: /* check for a useful key */
2099: private = NULL;
2100: for (i = 0; i < authctxt->sensitive->nkeys; i++) {
2101: if (authctxt->sensitive->keys[i] == NULL ||
2102: authctxt->sensitive->keys[i]->type == KEY_UNSPEC)
2103: continue;
2104: if (match_pattern_list(
2105: sshkey_ssh_name(authctxt->sensitive->keys[i]),
1.224 djm 2106: authctxt->active_ktype, 0) != 1)
1.223 djm 2107: continue;
1.68 markus 2108: /* we take and free the key */
1.223 djm 2109: private = authctxt->sensitive->keys[i];
2110: authctxt->sensitive->keys[i] = NULL;
1.68 markus 2111: break;
2112: }
1.223 djm 2113: /* Found one */
2114: if (private != NULL)
2115: break;
2116: /* No more keys of this type; advance */
2117: authctxt->active_ktype = NULL;
1.68 markus 2118: }
1.223 djm 2119: if (private == NULL) {
2120: free(authctxt->oktypes);
2121: authctxt->oktypes = authctxt->ktypes = NULL;
2122: authctxt->active_ktype = NULL;
1.109 markus 2123: debug("No more client hostkeys for hostbased authentication.");
1.223 djm 2124: goto out;
1.68 markus 2125: }
1.211 djm 2126:
1.223 djm 2127: if ((fp = sshkey_fingerprint(private, options.fingerprint_hash,
2128: SSH_FP_DEFAULT)) == NULL) {
1.331 djm 2129: error_f("sshkey_fingerprint failed");
1.223 djm 2130: goto out;
1.68 markus 2131: }
1.331 djm 2132: debug_f("trying hostkey %s %s", sshkey_ssh_name(private), fp);
1.211 djm 2133:
1.84 markus 2134: /* figure out a name for the client host */
1.295 djm 2135: lname = get_local_name(ssh_packet_get_connection_in(ssh));
2136: if (lname == NULL) {
1.331 djm 2137: error_f("cannot get local ipaddr/name");
1.223 djm 2138: goto out;
1.84 markus 2139: }
1.223 djm 2140:
2141: /* XXX sshbuf_put_stringf? */
2142: xasprintf(&chost, "%s.", lname);
1.331 djm 2143: debug2_f("chost %s", chost);
1.84 markus 2144:
1.68 markus 2145: /* construct data */
1.223 djm 2146: if ((b = sshbuf_new()) == NULL) {
1.331 djm 2147: error_f("sshbuf_new failed");
1.223 djm 2148: goto out;
2149: }
2150: if ((r = sshkey_to_blob(private, &keyblob, &keylen)) != 0) {
1.331 djm 2151: error_fr(r, "sshkey_to_blob");
1.223 djm 2152: goto out;
2153: }
2154: if ((r = sshbuf_put_string(b, session_id2, session_id2_len)) != 0 ||
2155: (r = sshbuf_put_u8(b, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
2156: (r = sshbuf_put_cstring(b, authctxt->server_user)) != 0 ||
1.267 djm 2157: (r = sshbuf_put_cstring(b, authctxt->service)) != 0 ||
1.223 djm 2158: (r = sshbuf_put_cstring(b, authctxt->method->name)) != 0 ||
1.279 markus 2159: (r = sshbuf_put_cstring(b, sshkey_ssh_name(private))) != 0 ||
1.223 djm 2160: (r = sshbuf_put_string(b, keyblob, keylen)) != 0 ||
2161: (r = sshbuf_put_cstring(b, chost)) != 0 ||
2162: (r = sshbuf_put_cstring(b, authctxt->local_user)) != 0) {
1.331 djm 2163: error_fr(r, "buffer error");
1.223 djm 2164: goto out;
2165: }
2166:
1.68 markus 2167: #ifdef DEBUG_PK
1.223 djm 2168: sshbuf_dump(b, stderr);
1.68 markus 2169: #endif
1.294 djm 2170: if ((r = ssh_keysign(ssh, private, &sig, &siglen,
2171: sshbuf_ptr(b), sshbuf_len(b))) != 0) {
1.223 djm 2172: error("sign using hostkey %s %s failed",
2173: sshkey_ssh_name(private), fp);
2174: goto out;
2175: }
2176: if ((r = sshpkt_start(ssh, SSH2_MSG_USERAUTH_REQUEST)) != 0 ||
2177: (r = sshpkt_put_cstring(ssh, authctxt->server_user)) != 0 ||
2178: (r = sshpkt_put_cstring(ssh, authctxt->service)) != 0 ||
2179: (r = sshpkt_put_cstring(ssh, authctxt->method->name)) != 0 ||
1.279 markus 2180: (r = sshpkt_put_cstring(ssh, sshkey_ssh_name(private))) != 0 ||
1.223 djm 2181: (r = sshpkt_put_string(ssh, keyblob, keylen)) != 0 ||
2182: (r = sshpkt_put_cstring(ssh, chost)) != 0 ||
2183: (r = sshpkt_put_cstring(ssh, authctxt->local_user)) != 0 ||
2184: (r = sshpkt_put_string(ssh, sig, siglen)) != 0 ||
2185: (r = sshpkt_send(ssh)) != 0) {
1.331 djm 2186: error_fr(r, "packet error");
1.223 djm 2187: goto out;
2188: }
2189: success = 1;
2190:
2191: out:
1.278 markus 2192: if (sig != NULL)
2193: freezero(sig, siglen);
1.223 djm 2194: free(keyblob);
2195: free(lname);
2196: free(fp);
1.197 djm 2197: free(chost);
1.223 djm 2198: sshkey_free(private);
2199: sshbuf_free(b);
1.68 markus 2200:
1.223 djm 2201: return success;
1.23 markus 2202: }
1.170 djm 2203:
1.20 markus 2204: /* find auth method */
2205:
2206: /*
2207: * given auth method name, if configurable options permit this method fill
2208: * in auth_ident field and return true, otherwise return false.
2209: */
1.76 itojun 2210: static int
1.20 markus 2211: authmethod_is_enabled(Authmethod *method)
2212: {
2213: if (method == NULL)
2214: return 0;
2215: /* return false if options indicate this method is disabled */
2216: if (method->enabled == NULL || *method->enabled == 0)
2217: return 0;
2218: /* return false if batch mode is enabled but method needs interactive mode */
2219: if (method->batch_flag != NULL && *method->batch_flag != 0)
2220: return 0;
2221: return 1;
2222: }
2223:
1.76 itojun 2224: static Authmethod *
1.20 markus 2225: authmethod_lookup(const char *name)
1.1 markus 2226: {
1.20 markus 2227: Authmethod *method = NULL;
2228: if (name != NULL)
2229: for (method = authmethods; method->name != NULL; method++)
2230: if (strcmp(name, method->name) == 0)
2231: return method;
2232: debug2("Unrecognized authentication method name: %s", name ? name : "NULL");
2233: return NULL;
2234: }
1.1 markus 2235:
1.53 markus 2236: /* XXX internal state */
2237: static Authmethod *current = NULL;
2238: static char *supported = NULL;
2239: static char *preferred = NULL;
1.105 deraadt 2240:
1.20 markus 2241: /*
2242: * Given the authentication method list sent by the server, return the
2243: * next method we should try. If the server initially sends a nil list,
1.67 markus 2244: * use a built-in default list.
1.41 stevesk 2245: */
1.76 itojun 2246: static Authmethod *
1.20 markus 2247: authmethod_get(char *authlist)
2248: {
1.53 markus 2249: char *name = NULL;
1.97 markus 2250: u_int next;
1.41 stevesk 2251:
1.20 markus 2252: /* Use a suitable default if we're passed a nil list. */
2253: if (authlist == NULL || strlen(authlist) == 0)
1.53 markus 2254: authlist = options.preferred_authentications;
1.20 markus 2255:
1.53 markus 2256: if (supported == NULL || strcmp(authlist, supported) != 0) {
2257: debug3("start over, passed a different list %s", authlist);
1.197 djm 2258: free(supported);
1.53 markus 2259: supported = xstrdup(authlist);
2260: preferred = options.preferred_authentications;
2261: debug3("preferred %s", preferred);
2262: current = NULL;
2263: } else if (current != NULL && authmethod_is_enabled(current))
2264: return current;
1.20 markus 2265:
1.53 markus 2266: for (;;) {
2267: if ((name = match_list(preferred, supported, &next)) == NULL) {
1.109 markus 2268: debug("No more authentication methods to try.");
1.53 markus 2269: current = NULL;
2270: return NULL;
2271: }
2272: preferred += next;
1.23 markus 2273: debug3("authmethod_lookup %s", name);
1.53 markus 2274: debug3("remaining preferred: %s", preferred);
2275: if ((current = authmethod_lookup(name)) != NULL &&
2276: authmethod_is_enabled(current)) {
1.23 markus 2277: debug3("authmethod_is_enabled %s", name);
1.109 markus 2278: debug("Next authentication method: %s", name);
1.197 djm 2279: free(name);
1.53 markus 2280: return current;
1.23 markus 2281: }
1.198 dtucker 2282: free(name);
1.1 markus 2283: }
1.53 markus 2284: }
1.1 markus 2285:
1.79 stevesk 2286: static char *
1.53 markus 2287: authmethods_get(void)
2288: {
2289: Authmethod *method = NULL;
1.278 markus 2290: struct sshbuf *b;
1.93 markus 2291: char *list;
1.278 markus 2292: int r;
1.27 provos 2293:
1.278 markus 2294: if ((b = sshbuf_new()) == NULL)
1.331 djm 2295: fatal_f("sshbuf_new failed");
1.53 markus 2296: for (method = authmethods; method->name != NULL; method++) {
2297: if (authmethod_is_enabled(method)) {
1.278 markus 2298: if ((r = sshbuf_putf(b, "%s%s",
2299: sshbuf_len(b) ? "," : "", method->name)) != 0)
1.331 djm 2300: fatal_fr(r, "buffer error");
1.53 markus 2301: }
2302: }
1.278 markus 2303: if ((list = sshbuf_dup_string(b)) == NULL)
1.331 djm 2304: fatal_f("sshbuf_dup_string failed");
1.278 markus 2305: sshbuf_free(b);
1.93 markus 2306: return list;
1.1 markus 2307: }
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