crypto/openssh-3.9p1/monitor_wrap.c

   1 /*
   2  * Copyright 2002 Niels Provos <provos@citi.umich.edu>
   3  * Copyright 2002 Markus Friedl <markus@openbsd.org>
   4  * All rights reserved.
   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
  27 #include "includes.h"
  28 RCSID("$OpenBSD: monitor_wrap.c,v 1.39 2004/07/17 05:31:41 dtucker Exp $");
  29
  30 #include <openssl/bn.h>
  31 #include <openssl/dh.h>
  32
  33 #include "ssh.h"
  34 #include "dh.h"
  35 #include "kex.h"
  36 #include "auth.h"
  37 #include "auth-options.h"
  38 #include "buffer.h"
  39 #include "bufaux.h"
  40 #include "packet.h"
  41 #include "mac.h"
  42 #include "log.h"
  43 #ifdef TARGET_OS_MAC    /* XXX Broken krb5 headers on Mac */
  44 #undef TARGET_OS_MAC
  45 #include "zlib.h"
  46 #define TARGET_OS_MAC 1
  47 #else
  48 #include "zlib.h"
  49 #endif
  50 #include "monitor.h"
  51 #include "monitor_wrap.h"
  52 #include "xmalloc.h"
  53 #include "atomicio.h"
  54 #include "monitor_fdpass.h"
  55 #include "getput.h"
  56 #include "servconf.h"
  57
  58 #include "auth.h"
  59 #include "channels.h"
  60 #include "session.h"
  61
  62 #ifdef GSSAPI
  63 #include "ssh-gss.h"
  64 #endif
  65
  66 /* Imports */
  67 extern int compat20;
  68 extern Newkeys *newkeys[];
  69 extern z_stream incoming_stream;
  70 extern z_stream outgoing_stream;
  71 extern struct monitor *pmonitor;
  72 extern Buffer input, output;
  73 extern Buffer loginmsg;
  74 extern ServerOptions options;
  75
  76 int
  77 mm_is_monitor(void)
  78 {
  79         /*
  80          * m_pid is only set in the privileged part, and
  81          * points to the unprivileged child.
  82          */
  83         return (pmonitor && pmonitor->m_pid > 0);
  84 }
  85
  86 void
  87 mm_request_send(int sock, enum monitor_reqtype type, Buffer *m)
  88 {
  89         u_int mlen = buffer_len(m);
  90         u_char buf[5];
  91
  92         debug3("%s entering: type %d", __func__, type);
  93
  94         PUT_32BIT(buf, mlen + 1);
  95         buf[4] = (u_char) type;         /* 1st byte of payload is mesg-type */
  96         if (atomicio(vwrite, sock, buf, sizeof(buf)) != sizeof(buf))
  97                 fatal("%s: write", __func__);
  98         if (atomicio(vwrite, sock, buffer_ptr(m), mlen) != mlen)
  99                 fatal("%s: write", __func__);
 100 }
 101
 102 void
 103 mm_request_receive(int sock, Buffer *m)
 104 {
 105         u_char buf[4];
 106         u_int msg_len;
 107         ssize_t res;
 108
 109         debug3("%s entering", __func__);
 110
 111         res = atomicio(read, sock, buf, sizeof(buf));
 112         if (res != sizeof(buf)) {
 113                 if (res == 0)
 114                         cleanup_exit(255);
 115                 fatal("%s: read: %ld", __func__, (long)res);
 116         }
 117         msg_len = GET_32BIT(buf);
 118         if (msg_len > 256 * 1024)
 119                 fatal("%s: read: bad msg_len %d", __func__, msg_len);
 120         buffer_clear(m);
 121         buffer_append_space(m, msg_len);
 122         res = atomicio(read, sock, buffer_ptr(m), msg_len);
 123         if (res != msg_len)
 124                 fatal("%s: read: %ld != msg_len", __func__, (long)res);
 125 }
 126
 127 void
 128 mm_request_receive_expect(int sock, enum monitor_reqtype type, Buffer *m)
 129 {
 130         u_char rtype;
 131
 132         debug3("%s entering: type %d", __func__, type);
 133
 134         mm_request_receive(sock, m);
 135         rtype = buffer_get_char(m);
 136         if (rtype != type)
 137                 fatal("%s: read: rtype %d != type %d", __func__,
 138                     rtype, type);
 139 }
 140
 141 DH *
 142 mm_choose_dh(int min, int nbits, int max)
 143 {
 144         BIGNUM *p, *g;
 145         int success = 0;
 146         Buffer m;
 147
 148         buffer_init(&m);
 149         buffer_put_int(&m, min);
 150         buffer_put_int(&m, nbits);
 151         buffer_put_int(&m, max);
 152
 153         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_MODULI, &m);
 154
 155         debug3("%s: waiting for MONITOR_ANS_MODULI", __func__);
 156         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_MODULI, &m);
 157
 158         success = buffer_get_char(&m);
 159         if (success == 0)
 160                 fatal("%s: MONITOR_ANS_MODULI failed", __func__);
 161
 162         if ((p = BN_new()) == NULL)
 163                 fatal("%s: BN_new failed", __func__);
 164         if ((g = BN_new()) == NULL)
 165                 fatal("%s: BN_new failed", __func__);
 166         buffer_get_bignum2(&m, p);
 167         buffer_get_bignum2(&m, g);
 168
 169         debug3("%s: remaining %d", __func__, buffer_len(&m));
 170         buffer_free(&m);
 171
 172         return (dh_new_group(g, p));
 173 }
 174
 175 int
 176 mm_key_sign(Key *key, u_char **sigp, u_int *lenp, u_char *data, u_int datalen)
 177 {
 178         Kex *kex = *pmonitor->m_pkex;
 179         Buffer m;
 180
 181         debug3("%s entering", __func__);
 182
 183         buffer_init(&m);
 184         buffer_put_int(&m, kex->host_key_index(key));
 185         buffer_put_string(&m, data, datalen);
 186
 187         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SIGN, &m);
 188
 189         debug3("%s: waiting for MONITOR_ANS_SIGN", __func__);
 190         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SIGN, &m);
 191         *sigp  = buffer_get_string(&m, lenp);
 192         buffer_free(&m);
 193
 194         return (0);
 195 }
 196
 197 struct passwd *
 198 mm_getpwnamallow(const char *username)
 199 {
 200         Buffer m;
 201         struct passwd *pw;
 202         u_int pwlen;
 203
 204         debug3("%s entering", __func__);
 205
 206         buffer_init(&m);
 207         buffer_put_cstring(&m, username);
 208
 209         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PWNAM, &m);
 210
 211         debug3("%s: waiting for MONITOR_ANS_PWNAM", __func__);
 212         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PWNAM, &m);
 213
 214         if (buffer_get_char(&m) == 0) {
 215                 buffer_free(&m);
 216                 return (NULL);
 217         }
 218         pw = buffer_get_string(&m, &pwlen);
 219         if (pwlen != sizeof(struct passwd))
 220                 fatal("%s: struct passwd size mismatch", __func__);
 221         pw->pw_name = buffer_get_string(&m, NULL);
 222         pw->pw_passwd = buffer_get_string(&m, NULL);
 223         pw->pw_gecos = buffer_get_string(&m, NULL);
 224 #ifdef HAVE_PW_CLASS_IN_PASSWD
 225         pw->pw_class = buffer_get_string(&m, NULL);
 226 #endif
 227         pw->pw_dir = buffer_get_string(&m, NULL);
 228         pw->pw_shell = buffer_get_string(&m, NULL);
 229         buffer_free(&m);
 230
 231         return (pw);
 232 }
 233
 234 char *
 235 mm_auth2_read_banner(void)
 236 {
 237         Buffer m;
 238         char *banner;
 239
 240         debug3("%s entering", __func__);
 241
 242         buffer_init(&m);
 243         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTH2_READ_BANNER, &m);
 244         buffer_clear(&m);
 245
 246         mm_request_receive_expect(pmonitor->m_recvfd,
 247             MONITOR_ANS_AUTH2_READ_BANNER, &m);
 248         banner = buffer_get_string(&m, NULL);
 249         buffer_free(&m);
 250
 251         /* treat empty banner as missing banner */
 252         if (strlen(banner) == 0) {
 253                 xfree(banner);
 254                 banner = NULL;
 255         }
 256         return (banner);
 257 }
 258
 259 /* Inform the privileged process about service and style */
 260
 261 void
 262 mm_inform_authserv(char *service, char *style)
 263 {
 264         Buffer m;
 265
 266         debug3("%s entering", __func__);
 267
 268         buffer_init(&m);
 269         buffer_put_cstring(&m, service);
 270         buffer_put_cstring(&m, style ? style : "");
 271
 272         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHSERV, &m);
 273
 274         buffer_free(&m);
 275 }
 276
 277 /* Do the password authentication */
 278 int
 279 mm_auth_password(Authctxt *authctxt, char *password)
 280 {
 281         Buffer m;
 282         int authenticated = 0;
 283
 284         debug3("%s entering", __func__);
 285
 286         buffer_init(&m);
 287         buffer_put_cstring(&m, password);
 288         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHPASSWORD, &m);
 289
 290         debug3("%s: waiting for MONITOR_ANS_AUTHPASSWORD", __func__);
 291         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_AUTHPASSWORD, &m);
 292
 293         authenticated = buffer_get_int(&m);
 294
 295         buffer_free(&m);
 296
 297         debug3("%s: user %sauthenticated",
 298             __func__, authenticated ? "" : "not ");
 299         return (authenticated);
 300 }
 301
 302 int
 303 mm_user_key_allowed(struct passwd *pw, Key *key)
 304 {
 305         return (mm_key_allowed(MM_USERKEY, NULL, NULL, key));
 306 }
 307
 308 int
 309 mm_hostbased_key_allowed(struct passwd *pw, char *user, char *host,
 310     Key *key)
 311 {
 312         return (mm_key_allowed(MM_HOSTKEY, user, host, key));
 313 }
 314
 315 int
 316 mm_auth_rhosts_rsa_key_allowed(struct passwd *pw, char *user,
 317     char *host, Key *key)
 318 {
 319         int ret;
 320
 321         key->type = KEY_RSA; /* XXX hack for key_to_blob */
 322         ret = mm_key_allowed(MM_RSAHOSTKEY, user, host, key);
 323         key->type = KEY_RSA1;
 324         return (ret);
 325 }
 326
 327 static void
 328 mm_send_debug(Buffer *m)
 329 {
 330         char *msg;
 331
 332         while (buffer_len(m)) {
 333                 msg = buffer_get_string(m, NULL);
 334                 debug3("%s: Sending debug: %s", __func__, msg);
 335                 packet_send_debug("%s", msg);
 336                 xfree(msg);
 337         }
 338 }
 339
 340 int
 341 mm_key_allowed(enum mm_keytype type, char *user, char *host, Key *key)
 342 {
 343         Buffer m;
 344         u_char *blob;
 345         u_int len;
 346         int allowed = 0, have_forced = 0;
 347
 348         debug3("%s entering", __func__);
 349
 350         /* Convert the key to a blob and the pass it over */
 351         if (!key_to_blob(key, &blob, &len))
 352                 return (0);
 353
 354         buffer_init(&m);
 355         buffer_put_int(&m, type);
 356         buffer_put_cstring(&m, user ? user : "");
 357         buffer_put_cstring(&m, host ? host : "");
 358         buffer_put_string(&m, blob, len);
 359         xfree(blob);
 360
 361         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYALLOWED, &m);
 362
 363         debug3("%s: waiting for MONITOR_ANS_KEYALLOWED", __func__);
 364         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_KEYALLOWED, &m);
 365
 366         allowed = buffer_get_int(&m);
 367
 368         /* fake forced command */
 369         auth_clear_options();
 370         have_forced = buffer_get_int(&m);
 371         forced_command = have_forced ? xstrdup("true") : NULL;
 372
 373         /* Send potential debug messages */
 374         mm_send_debug(&m);
 375
 376         buffer_free(&m);
 377
 378         return (allowed);
 379 }
 380
 381 /*
 382  * This key verify needs to send the key type along, because the
 383  * privileged parent makes the decision if the key is allowed
 384  * for authentication.
 385  */
 386
 387 int
 388 mm_key_verify(Key *key, u_char *sig, u_int siglen, u_char *data, u_int datalen)
 389 {
 390         Buffer m;
 391         u_char *blob;
 392         u_int len;
 393         int verified = 0;
 394
 395         debug3("%s entering", __func__);
 396
 397         /* Convert the key to a blob and the pass it over */
 398         if (!key_to_blob(key, &blob, &len))
 399                 return (0);
 400
 401         buffer_init(&m);
 402         buffer_put_string(&m, blob, len);
 403         buffer_put_string(&m, sig, siglen);
 404         buffer_put_string(&m, data, datalen);
 405         xfree(blob);
 406
 407         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYVERIFY, &m);
 408
 409         debug3("%s: waiting for MONITOR_ANS_KEYVERIFY", __func__);
 410         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_KEYVERIFY, &m);
 411
 412         verified = buffer_get_int(&m);
 413
 414         buffer_free(&m);
 415
 416         return (verified);
 417 }
 418
 419 /* Export key state after authentication */
 420 Newkeys *
 421 mm_newkeys_from_blob(u_char *blob, int blen)
 422 {
 423         Buffer b;
 424         u_int len;
 425         Newkeys *newkey = NULL;
 426         Enc *enc;
 427         Mac *mac;
 428         Comp *comp;
 429
 430         debug3("%s: %p(%d)", __func__, blob, blen);
 431 #ifdef DEBUG_PK
 432         dump_base64(stderr, blob, blen);
 433 #endif
 434         buffer_init(&b);
 435         buffer_append(&b, blob, blen);
 436
 437         newkey = xmalloc(sizeof(*newkey));
 438         enc = &newkey->enc;
 439         mac = &newkey->mac;
 440         comp = &newkey->comp;
 441
 442         /* Enc structure */
 443         enc->name = buffer_get_string(&b, NULL);
 444         buffer_get(&b, &enc->cipher, sizeof(enc->cipher));
 445         enc->enabled = buffer_get_int(&b);
 446         enc->block_size = buffer_get_int(&b);
 447         enc->key = buffer_get_string(&b, &enc->key_len);
 448         enc->iv = buffer_get_string(&b, &len);
 449         if (len != enc->block_size)
 450                 fatal("%s: bad ivlen: expected %u != %u", __func__,
 451                     enc->block_size, len);
 452
 453         if (enc->name == NULL || cipher_by_name(enc->name) != enc->cipher)
 454                 fatal("%s: bad cipher name %s or pointer %p", __func__,
 455                     enc->name, enc->cipher);
 456
 457         /* Mac structure */
 458         mac->name = buffer_get_string(&b, NULL);
 459         if (mac->name == NULL || mac_init(mac, mac->name) == -1)
 460                 fatal("%s: can not init mac %s", __func__, mac->name);
 461         mac->enabled = buffer_get_int(&b);
 462         mac->key = buffer_get_string(&b, &len);
 463         if (len > mac->key_len)
 464                 fatal("%s: bad mac key length: %u > %d", __func__, len,
 465                     mac->key_len);
 466         mac->key_len = len;
 467
 468         /* Comp structure */
 469         comp->type = buffer_get_int(&b);
 470         comp->enabled = buffer_get_int(&b);
 471         comp->name = buffer_get_string(&b, NULL);
 472
 473         len = buffer_len(&b);
 474         if (len != 0)
 475                 error("newkeys_from_blob: remaining bytes in blob %u", len);
 476         buffer_free(&b);
 477         return (newkey);
 478 }
 479
 480 int
 481 mm_newkeys_to_blob(int mode, u_char **blobp, u_int *lenp)
 482 {
 483         Buffer b;
 484         int len;
 485         Enc *enc;
 486         Mac *mac;
 487         Comp *comp;
 488         Newkeys *newkey = newkeys[mode];
 489
 490         debug3("%s: converting %p", __func__, newkey);
 491
 492         if (newkey == NULL) {
 493                 error("%s: newkey == NULL", __func__);
 494                 return 0;
 495         }
 496         enc = &newkey->enc;
 497         mac = &newkey->mac;
 498         comp = &newkey->comp;
 499
 500         buffer_init(&b);
 501         /* Enc structure */
 502         buffer_put_cstring(&b, enc->name);
 503         /* The cipher struct is constant and shared, you export pointer */
 504         buffer_append(&b, &enc->cipher, sizeof(enc->cipher));
 505         buffer_put_int(&b, enc->enabled);
 506         buffer_put_int(&b, enc->block_size);
 507         buffer_put_string(&b, enc->key, enc->key_len);
 508         packet_get_keyiv(mode, enc->iv, enc->block_size);
 509         buffer_put_string(&b, enc->iv, enc->block_size);
 510
 511         /* Mac structure */
 512         buffer_put_cstring(&b, mac->name);
 513         buffer_put_int(&b, mac->enabled);
 514         buffer_put_string(&b, mac->key, mac->key_len);
 515
 516         /* Comp structure */
 517         buffer_put_int(&b, comp->type);
 518         buffer_put_int(&b, comp->enabled);
 519         buffer_put_cstring(&b, comp->name);
 520
 521         len = buffer_len(&b);
 522         if (lenp != NULL)
 523                 *lenp = len;
 524         if (blobp != NULL) {
 525                 *blobp = xmalloc(len);
 526                 memcpy(*blobp, buffer_ptr(&b), len);
 527         }
 528         memset(buffer_ptr(&b), 0, len);
 529         buffer_free(&b);
 530         return len;
 531 }
 532
 533 static void
 534 mm_send_kex(Buffer *m, Kex *kex)
 535 {
 536         buffer_put_string(m, kex->session_id, kex->session_id_len);
 537         buffer_put_int(m, kex->we_need);
 538         buffer_put_int(m, kex->hostkey_type);
 539         buffer_put_int(m, kex->kex_type);
 540         buffer_put_string(m, buffer_ptr(&kex->my), buffer_len(&kex->my));
 541         buffer_put_string(m, buffer_ptr(&kex->peer), buffer_len(&kex->peer));
 542         buffer_put_int(m, kex->flags);
 543         buffer_put_cstring(m, kex->client_version_string);
 544         buffer_put_cstring(m, kex->server_version_string);
 545 }
 546
 547 void
 548 mm_send_keystate(struct monitor *monitor)
 549 {
 550         Buffer m;
 551         u_char *blob, *p;
 552         u_int bloblen, plen;
 553         u_int32_t seqnr, packets;
 554         u_int64_t blocks;
 555
 556         buffer_init(&m);
 557
 558         if (!compat20) {
 559                 u_char iv[24];
 560                 u_char *key;
 561                 u_int ivlen, keylen;
 562
 563                 buffer_put_int(&m, packet_get_protocol_flags());
 564
 565                 buffer_put_int(&m, packet_get_ssh1_cipher());
 566
 567                 debug3("%s: Sending ssh1 KEY+IV", __func__);
 568                 keylen = packet_get_encryption_key(NULL);
 569                 key = xmalloc(keylen+1);        /* add 1 if keylen == 0 */
 570                 keylen = packet_get_encryption_key(key);
 571                 buffer_put_string(&m, key, keylen);
 572                 memset(key, 0, keylen);
 573                 xfree(key);
 574
 575                 ivlen = packet_get_keyiv_len(MODE_OUT);
 576                 packet_get_keyiv(MODE_OUT, iv, ivlen);
 577                 buffer_put_string(&m, iv, ivlen);
 578                 ivlen = packet_get_keyiv_len(MODE_OUT);
 579                 packet_get_keyiv(MODE_IN, iv, ivlen);
 580                 buffer_put_string(&m, iv, ivlen);
 581                 goto skip;
 582         } else {
 583                 /* Kex for rekeying */
 584                 mm_send_kex(&m, *monitor->m_pkex);
 585         }
 586
 587         debug3("%s: Sending new keys: %p %p",
 588             __func__, newkeys[MODE_OUT], newkeys[MODE_IN]);
 589
 590         /* Keys from Kex */
 591         if (!mm_newkeys_to_blob(MODE_OUT, &blob, &bloblen))
 592                 fatal("%s: conversion of newkeys failed", __func__);
 593
 594         buffer_put_string(&m, blob, bloblen);
 595         xfree(blob);
 596
 597         if (!mm_newkeys_to_blob(MODE_IN, &blob, &bloblen))
 598                 fatal("%s: conversion of newkeys failed", __func__);
 599
 600         buffer_put_string(&m, blob, bloblen);
 601         xfree(blob);
 602
 603         packet_get_state(MODE_OUT, &seqnr, &blocks, &packets);
 604         buffer_put_int(&m, seqnr);
 605         buffer_put_int64(&m, blocks);
 606         buffer_put_int(&m, packets);
 607         packet_get_state(MODE_IN, &seqnr, &blocks, &packets);
 608         buffer_put_int(&m, seqnr);
 609         buffer_put_int64(&m, blocks);
 610         buffer_put_int(&m, packets);
 611
 612         debug3("%s: New keys have been sent", __func__);
 613  skip:
 614         /* More key context */
 615         plen = packet_get_keycontext(MODE_OUT, NULL);
 616         p = xmalloc(plen+1);
 617         packet_get_keycontext(MODE_OUT, p);
 618         buffer_put_string(&m, p, plen);
 619         xfree(p);
 620
 621         plen = packet_get_keycontext(MODE_IN, NULL);
 622         p = xmalloc(plen+1);
 623         packet_get_keycontext(MODE_IN, p);
 624         buffer_put_string(&m, p, plen);
 625         xfree(p);
 626
 627         /* Compression state */
 628         debug3("%s: Sending compression state", __func__);
 629         buffer_put_string(&m, &outgoing_stream, sizeof(outgoing_stream));
 630         buffer_put_string(&m, &incoming_stream, sizeof(incoming_stream));
 631
 632         /* Network I/O buffers */
 633         buffer_put_string(&m, buffer_ptr(&input), buffer_len(&input));
 634         buffer_put_string(&m, buffer_ptr(&output), buffer_len(&output));
 635
 636         mm_request_send(monitor->m_recvfd, MONITOR_REQ_KEYEXPORT, &m);
 637         debug3("%s: Finished sending state", __func__);
 638
 639         buffer_free(&m);
 640 }
 641
 642 int
 643 mm_pty_allocate(int *ptyfd, int *ttyfd, char *namebuf, int namebuflen)
 644 {
 645         Buffer m;
 646         char *p, *msg;
 647         int success = 0;
 648
 649         buffer_init(&m);
 650         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTY, &m);
 651
 652         debug3("%s: waiting for MONITOR_ANS_PTY", __func__);
 653         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PTY, &m);
 654
 655         success = buffer_get_int(&m);
 656         if (success == 0) {
 657                 debug3("%s: pty alloc failed", __func__);
 658                 buffer_free(&m);
 659                 return (0);
 660         }
 661         p = buffer_get_string(&m, NULL);
 662         msg = buffer_get_string(&m, NULL);
 663         buffer_free(&m);
 664
 665         strlcpy(namebuf, p, namebuflen); /* Possible truncation */
 666         xfree(p);
 667
 668         buffer_append(&loginmsg, msg, strlen(msg));
 669         xfree(msg);
 670
 671         *ptyfd = mm_receive_fd(pmonitor->m_recvfd);
 672         *ttyfd = mm_receive_fd(pmonitor->m_recvfd);
 673
 674         /* Success */
 675         return (1);
 676 }
 677
 678 void
 679 mm_session_pty_cleanup2(Session *s)
 680 {
 681         Buffer m;
 682
 683         if (s->ttyfd == -1)
 684                 return;
 685         buffer_init(&m);
 686         buffer_put_cstring(&m, s->tty);
 687         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTYCLEANUP, &m);
 688         buffer_free(&m);
 689
 690         /* closed dup'ed master */
 691         if (close(s->ptymaster) < 0)
 692                 error("close(s->ptymaster): %s", strerror(errno));
 693
 694         /* unlink pty from session */
 695         s->ttyfd = -1;
 696 }
 697
 698 #ifdef USE_PAM
 699 void
 700 mm_start_pam(Authctxt *authctxt)
 701 {
 702         Buffer m;
 703
 704         debug3("%s entering", __func__);
 705         if (!options.use_pam)
 706                 fatal("UsePAM=no, but ended up in %s anyway", __func__);
 707
 708         buffer_init(&m);
 709         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_START, &m);
 710
 711         buffer_free(&m);
 712 }
 713
 714 u_int
 715 mm_do_pam_account(void)
 716 {
 717         Buffer m;
 718         u_int ret;
 719
 720         debug3("%s entering", __func__);
 721         if (!options.use_pam)
 722                 fatal("UsePAM=no, but ended up in %s anyway", __func__);
 723
 724         buffer_init(&m);
 725         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_ACCOUNT, &m);
 726
 727         mm_request_receive_expect(pmonitor->m_recvfd,
 728             MONITOR_ANS_PAM_ACCOUNT, &m);
 729         ret = buffer_get_int(&m);
 730
 731         buffer_free(&m);
 732
 733         debug3("%s returning %d", __func__, ret);
 734
 735         return (ret);
 736 }
 737
 738 void *
 739 mm_sshpam_init_ctx(Authctxt *authctxt)
 740 {
 741         Buffer m;
 742         int success;
 743
 744         debug3("%s", __func__);
 745         buffer_init(&m);
 746         buffer_put_cstring(&m, authctxt->user);
 747         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_INIT_CTX, &m);
 748         debug3("%s: waiting for MONITOR_ANS_PAM_INIT_CTX", __func__);
 749         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_INIT_CTX, &m);
 750         success = buffer_get_int(&m);
 751         if (success == 0) {
 752                 debug3("%s: pam_init_ctx failed", __func__);
 753                 buffer_free(&m);
 754                 return (NULL);
 755         }
 756         buffer_free(&m);
 757         return (authctxt);
 758 }
 759
 760 int
 761 mm_sshpam_query(void *ctx, char **name, char **info,
 762     u_int *num, char ***prompts, u_int **echo_on)
 763 {
 764         Buffer m;
 765         int i, ret;
 766
 767         debug3("%s", __func__);
 768         buffer_init(&m);
 769         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_QUERY, &m);
 770         debug3("%s: waiting for MONITOR_ANS_PAM_QUERY", __func__);
 771         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_QUERY, &m);
 772         ret = buffer_get_int(&m);
 773         debug3("%s: pam_query returned %d", __func__, ret);
 774         *name = buffer_get_string(&m, NULL);
 775         *info = buffer_get_string(&m, NULL);
 776         *num = buffer_get_int(&m);
 777         *prompts = xmalloc((*num + 1) * sizeof(char *));
 778         *echo_on = xmalloc((*num + 1) * sizeof(u_int));
 779         for (i = 0; i < *num; ++i) {
 780                 (*prompts)[i] = buffer_get_string(&m, NULL);
 781                 (*echo_on)[i] = buffer_get_int(&m);
 782         }
 783         buffer_free(&m);
 784         return (ret);
 785 }
 786
 787 int
 788 mm_sshpam_respond(void *ctx, u_int num, char **resp)
 789 {
 790         Buffer m;
 791         int i, ret;
 792
 793         debug3("%s", __func__);
 794         buffer_init(&m);
 795         buffer_put_int(&m, num);
 796         for (i = 0; i < num; ++i)
 797                 buffer_put_cstring(&m, resp[i]);
 798         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_RESPOND, &m);
 799         debug3("%s: waiting for MONITOR_ANS_PAM_RESPOND", __func__);
 800         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_RESPOND, &m);
 801         ret = buffer_get_int(&m);
 802         debug3("%s: pam_respond returned %d", __func__, ret);
 803         buffer_free(&m);
 804         return (ret);
 805 }
 806
 807 void
 808 mm_sshpam_free_ctx(void *ctxtp)
 809 {
 810         Buffer m;
 811
 812         debug3("%s", __func__);
 813         buffer_init(&m);
 814         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_FREE_CTX, &m);
 815         debug3("%s: waiting for MONITOR_ANS_PAM_FREE_CTX", __func__);
 816         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_FREE_CTX, &m);
 817         buffer_free(&m);
 818 }
 819 #endif /* USE_PAM */
 820
 821 /* Request process termination */
 822
 823 void
 824 mm_terminate(void)
 825 {
 826         Buffer m;
 827
 828         buffer_init(&m);
 829         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_TERM, &m);
 830         buffer_free(&m);
 831 }
 832
 833 int
 834 mm_ssh1_session_key(BIGNUM *num)
 835 {
 836         int rsafail;
 837         Buffer m;
 838
 839         buffer_init(&m);
 840         buffer_put_bignum2(&m, num);
 841         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SESSKEY, &m);
 842
 843         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SESSKEY, &m);
 844
 845         rsafail = buffer_get_int(&m);
 846         buffer_get_bignum2(&m, num);
 847
 848         buffer_free(&m);
 849
 850         return (rsafail);
 851 }
 852
 853 static void
 854 mm_chall_setup(char **name, char **infotxt, u_int *numprompts,
 855     char ***prompts, u_int **echo_on)
 856 {
 857         *name = xstrdup("");
 858         *infotxt = xstrdup("");
 859         *numprompts = 1;
 860         *prompts = xmalloc(*numprompts * sizeof(char *));
 861         *echo_on = xmalloc(*numprompts * sizeof(u_int));
 862         (*echo_on)[0] = 0;
 863 }
 864
 865 int
 866 mm_bsdauth_query(void *ctx, char **name, char **infotxt,
 867    u_int *numprompts, char ***prompts, u_int **echo_on)
 868 {
 869         Buffer m;
 870         u_int success;
 871         char *challenge;
 872
 873         debug3("%s: entering", __func__);
 874
 875         buffer_init(&m);
 876         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHQUERY, &m);
 877
 878         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_BSDAUTHQUERY,
 879             &m);
 880         success = buffer_get_int(&m);
 881         if (success == 0) {
 882                 debug3("%s: no challenge", __func__);
 883                 buffer_free(&m);
 884                 return (-1);
 885         }
 886
 887         /* Get the challenge, and format the response */
 888         challenge  = buffer_get_string(&m, NULL);
 889         buffer_free(&m);
 890
 891         mm_chall_setup(name, infotxt, numprompts, prompts, echo_on);
 892         (*prompts)[0] = challenge;
 893
 894         debug3("%s: received challenge: %s", __func__, challenge);
 895
 896         return (0);
 897 }
 898
 899 int
 900 mm_bsdauth_respond(void *ctx, u_int numresponses, char **responses)
 901 {
 902         Buffer m;
 903         int authok;
 904
 905         debug3("%s: entering", __func__);
 906         if (numresponses != 1)
 907                 return (-1);
 908
 909         buffer_init(&m);
 910         buffer_put_cstring(&m, responses[0]);
 911         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHRESPOND, &m);
 912
 913         mm_request_receive_expect(pmonitor->m_recvfd,
 914             MONITOR_ANS_BSDAUTHRESPOND, &m);
 915
 916         authok = buffer_get_int(&m);
 917         buffer_free(&m);
 918
 919         return ((authok == 0) ? -1 : 0);
 920 }
 921
 922 #ifdef SKEY
 923 int
 924 mm_skey_query(void *ctx, char **name, char **infotxt,
 925    u_int *numprompts, char ***prompts, u_int **echo_on)
 926 {
 927         Buffer m;
 928         int len;
 929         u_int success;
 930         char *p, *challenge;
 931
 932         debug3("%s: entering", __func__);
 933
 934         buffer_init(&m);
 935         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SKEYQUERY, &m);
 936
 937         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SKEYQUERY,
 938             &m);
 939         success = buffer_get_int(&m);
 940         if (success == 0) {
 941                 debug3("%s: no challenge", __func__);
 942                 buffer_free(&m);
 943                 return (-1);
 944         }
 945
 946         /* Get the challenge, and format the response */
 947         challenge  = buffer_get_string(&m, NULL);
 948         buffer_free(&m);
 949
 950         debug3("%s: received challenge: %s", __func__, challenge);
 951
 952         mm_chall_setup(name, infotxt, numprompts, prompts, echo_on);
 953
 954         len = strlen(challenge) + strlen(SKEY_PROMPT) + 1;
 955         p = xmalloc(len);
 956         strlcpy(p, challenge, len);
 957         strlcat(p, SKEY_PROMPT, len);
 958         (*prompts)[0] = p;
 959         xfree(challenge);
 960
 961         return (0);
 962 }
 963
 964 int
 965 mm_skey_respond(void *ctx, u_int numresponses, char **responses)
 966 {
 967         Buffer m;
 968         int authok;
 969
 970         debug3("%s: entering", __func__);
 971         if (numresponses != 1)
 972                 return (-1);
 973
 974         buffer_init(&m);
 975         buffer_put_cstring(&m, responses[0]);
 976         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SKEYRESPOND, &m);
 977
 978         mm_request_receive_expect(pmonitor->m_recvfd,
 979             MONITOR_ANS_SKEYRESPOND, &m);
 980
 981         authok = buffer_get_int(&m);
 982         buffer_free(&m);
 983
 984         return ((authok == 0) ? -1 : 0);
 985 }
 986 #endif /* SKEY */
 987
 988 void
 989 mm_ssh1_session_id(u_char session_id[16])
 990 {
 991         Buffer m;
 992         int i;
 993
 994         debug3("%s entering", __func__);
 995
 996         buffer_init(&m);
 997         for (i = 0; i < 16; i++)
 998                 buffer_put_char(&m, session_id[i]);
 999
1000         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SESSID, &m);
1001         buffer_free(&m);
1002 }
1003
1004 int
1005 mm_auth_rsa_key_allowed(struct passwd *pw, BIGNUM *client_n, Key **rkey)
1006 {
1007         Buffer m;
1008         Key *key;
1009         u_char *blob;
1010         u_int blen;
1011         int allowed = 0, have_forced = 0;
1012
1013         debug3("%s entering", __func__);
1014
1015         buffer_init(&m);
1016         buffer_put_bignum2(&m, client_n);
1017
1018         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSAKEYALLOWED, &m);
1019         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSAKEYALLOWED, &m);
1020
1021         allowed = buffer_get_int(&m);
1022
1023         /* fake forced command */
1024         auth_clear_options();
1025         have_forced = buffer_get_int(&m);
1026         forced_command = have_forced ? xstrdup("true") : NULL;
1027
1028         if (allowed && rkey != NULL) {
1029                 blob = buffer_get_string(&m, &blen);
1030                 if ((key = key_from_blob(blob, blen)) == NULL)
1031                         fatal("%s: key_from_blob failed", __func__);
1032                 *rkey = key;
1033                 xfree(blob);
1034         }
1035         mm_send_debug(&m);
1036         buffer_free(&m);
1037
1038         return (allowed);
1039 }
1040
1041 BIGNUM *
1042 mm_auth_rsa_generate_challenge(Key *key)
1043 {
1044         Buffer m;
1045         BIGNUM *challenge;
1046         u_char *blob;
1047         u_int blen;
1048
1049         debug3("%s entering", __func__);
1050
1051         if ((challenge = BN_new()) == NULL)
1052                 fatal("%s: BN_new failed", __func__);
1053
1054         key->type = KEY_RSA;    /* XXX cheat for key_to_blob */
1055         if (key_to_blob(key, &blob, &blen) == 0)
1056                 fatal("%s: key_to_blob failed", __func__);
1057         key->type = KEY_RSA1;
1058
1059         buffer_init(&m);
1060         buffer_put_string(&m, blob, blen);
1061         xfree(blob);
1062
1063         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSACHALLENGE, &m);
1064         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSACHALLENGE, &m);
1065
1066         buffer_get_bignum2(&m, challenge);
1067         buffer_free(&m);
1068
1069         return (challenge);
1070 }
1071
1072 int
1073 mm_auth_rsa_verify_response(Key *key, BIGNUM *p, u_char response[16])
1074 {
1075         Buffer m;
1076         u_char *blob;
1077         u_int blen;
1078         int success = 0;
1079
1080         debug3("%s entering", __func__);
1081
1082         key->type = KEY_RSA;    /* XXX cheat for key_to_blob */
1083         if (key_to_blob(key, &blob, &blen) == 0)
1084                 fatal("%s: key_to_blob failed", __func__);
1085         key->type = KEY_RSA1;
1086
1087         buffer_init(&m);
1088         buffer_put_string(&m, blob, blen);
1089         buffer_put_string(&m, response, 16);
1090         xfree(blob);
1091
1092         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSARESPONSE, &m);
1093         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSARESPONSE, &m);
1094
1095         success = buffer_get_int(&m);
1096         buffer_free(&m);
1097
1098         return (success);
1099 }
1100
1101 #ifdef GSSAPI
1102 OM_uint32
1103 mm_ssh_gssapi_server_ctx(Gssctxt **ctx, gss_OID goid)
1104 {
1105         Buffer m;
1106         OM_uint32 major;
1107
1108         /* Client doesn't get to see the context */
1109         *ctx = NULL;
1110
1111         buffer_init(&m);
1112         buffer_put_string(&m, goid->elements, goid->length);
1113
1114         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSETUP, &m);
1115         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSETUP, &m);
1116
1117         major = buffer_get_int(&m);
1118
1119         buffer_free(&m);
1120         return (major);
1121 }
1122
1123 OM_uint32
1124 mm_ssh_gssapi_accept_ctx(Gssctxt *ctx, gss_buffer_desc *in,
1125     gss_buffer_desc *out, OM_uint32 *flags)
1126 {
1127         Buffer m;
1128         OM_uint32 major;
1129         u_int len;
1130
1131         buffer_init(&m);
1132         buffer_put_string(&m, in->value, in->length);
1133
1134         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSTEP, &m);
1135         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSTEP, &m);
1136
1137         major = buffer_get_int(&m);
1138         out->value = buffer_get_string(&m, &len);
1139         out->length = len;
1140         if (flags)
1141                 *flags = buffer_get_int(&m);
1142
1143         buffer_free(&m);
1144
1145         return (major);
1146 }
1147
1148 OM_uint32
1149 mm_ssh_gssapi_checkmic(Gssctxt *ctx, gss_buffer_t gssbuf, gss_buffer_t gssmic)
1150 {
1151         Buffer m;
1152         OM_uint32 major;
1153
1154         buffer_init(&m);
1155         buffer_put_string(&m, gssbuf->value, gssbuf->length);
1156         buffer_put_string(&m, gssmic->value, gssmic->length);
1157
1158         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSCHECKMIC, &m);
1159         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSCHECKMIC,
1160             &m);
1161
1162         major = buffer_get_int(&m);
1163         buffer_free(&m);
1164         return(major);
1165 }
1166
1167 int
1168 mm_ssh_gssapi_userok(char *user)
1169 {
1170         Buffer m;
1171         int authenticated = 0;
1172
1173         buffer_init(&m);
1174
1175         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSUSEROK, &m);
1176         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSUSEROK,
1177                                   &m);
1178
1179         authenticated = buffer_get_int(&m);
1180
1181         buffer_free(&m);
1182         debug3("%s: user %sauthenticated",__func__, authenticated ? "" : "not ");
1183         return (authenticated);
1184 }
1185 #endif /* GSSAPI */