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 extern Buffer loginmsg;
  76
  77 int
  78 mm_is_monitor(void)
  79 {
  80         /*
  81          * m_pid is only set in the privileged part, and
  82          * points to the unprivileged child.
  83          */
  84         return (pmonitor && pmonitor->m_pid > 0);
  85 }
  86
  87 void
  88 mm_request_send(int sock, enum monitor_reqtype type, Buffer *m)
  89 {
  90         u_int mlen = buffer_len(m);
  91         u_char buf[5];
  92
  93         debug3("%s entering: type %d", __func__, type);
  94
  95         PUT_32BIT(buf, mlen + 1);
  96         buf[4] = (u_char) type;         /* 1st byte of payload is mesg-type */
  97         if (atomicio(vwrite, sock, buf, sizeof(buf)) != sizeof(buf))
  98                 fatal("%s: write", __func__);
  99         if (atomicio(vwrite, sock, buffer_ptr(m), mlen) != mlen)
 100                 fatal("%s: write", __func__);
 101 }
 102
 103 void
 104 mm_request_receive(int sock, Buffer *m)
 105 {
 106         u_char buf[4];
 107         u_int msg_len;
 108         ssize_t res;
 109
 110         debug3("%s entering", __func__);
 111
 112         res = atomicio(read, sock, buf, sizeof(buf));
 113         if (res != sizeof(buf)) {
 114                 if (res == 0)
 115                         cleanup_exit(255);
 116                 fatal("%s: read: %ld", __func__, (long)res);
 117         }
 118         msg_len = GET_32BIT(buf);
 119         if (msg_len > 256 * 1024)
 120                 fatal("%s: read: bad msg_len %d", __func__, msg_len);
 121         buffer_clear(m);
 122         buffer_append_space(m, msg_len);
 123         res = atomicio(read, sock, buffer_ptr(m), msg_len);
 124         if (res != msg_len)
 125                 fatal("%s: read: %ld != msg_len", __func__, (long)res);
 126 }
 127
 128 void
 129 mm_request_receive_expect(int sock, enum monitor_reqtype type, Buffer *m)
 130 {
 131         u_char rtype;
 132
 133         debug3("%s entering: type %d", __func__, type);
 134
 135         mm_request_receive(sock, m);
 136         rtype = buffer_get_char(m);
 137         if (rtype != type)
 138                 fatal("%s: read: rtype %d != type %d", __func__,
 139                     rtype, type);
 140 }
 141
 142 DH *
 143 mm_choose_dh(int min, int nbits, int max)
 144 {
 145         BIGNUM *p, *g;
 146         int success = 0;
 147         Buffer m;
 148
 149         buffer_init(&m);
 150         buffer_put_int(&m, min);
 151         buffer_put_int(&m, nbits);
 152         buffer_put_int(&m, max);
 153
 154         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_MODULI, &m);
 155
 156         debug3("%s: waiting for MONITOR_ANS_MODULI", __func__);
 157         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_MODULI, &m);
 158
 159         success = buffer_get_char(&m);
 160         if (success == 0)
 161                 fatal("%s: MONITOR_ANS_MODULI failed", __func__);
 162
 163         if ((p = BN_new()) == NULL)
 164                 fatal("%s: BN_new failed", __func__);
 165         if ((g = BN_new()) == NULL)
 166                 fatal("%s: BN_new failed", __func__);
 167         buffer_get_bignum2(&m, p);
 168         buffer_get_bignum2(&m, g);
 169
 170         debug3("%s: remaining %d", __func__, buffer_len(&m));
 171         buffer_free(&m);
 172
 173         return (dh_new_group(g, p));
 174 }
 175
 176 int
 177 mm_key_sign(Key *key, u_char **sigp, u_int *lenp, u_char *data, u_int datalen)
 178 {
 179         Kex *kex = *pmonitor->m_pkex;
 180         Buffer m;
 181
 182         debug3("%s entering", __func__);
 183
 184         buffer_init(&m);
 185         buffer_put_int(&m, kex->host_key_index(key));
 186         buffer_put_string(&m, data, datalen);
 187
 188         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SIGN, &m);
 189
 190         debug3("%s: waiting for MONITOR_ANS_SIGN", __func__);
 191         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SIGN, &m);
 192         *sigp  = buffer_get_string(&m, lenp);
 193         buffer_free(&m);
 194
 195         return (0);
 196 }
 197
 198 struct passwd *
 199 mm_getpwnamallow(const char *username)
 200 {
 201         Buffer m;
 202         struct passwd *pw;
 203         u_int pwlen;
 204
 205         debug3("%s entering", __func__);
 206
 207         buffer_init(&m);
 208         buffer_put_cstring(&m, username);
 209
 210         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PWNAM, &m);
 211
 212         debug3("%s: waiting for MONITOR_ANS_PWNAM", __func__);
 213         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PWNAM, &m);
 214
 215         if (buffer_get_char(&m) == 0) {
 216                 buffer_free(&m);
 217                 return (NULL);
 218         }
 219         pw = buffer_get_string(&m, &pwlen);
 220         if (pwlen != sizeof(struct passwd))
 221                 fatal("%s: struct passwd size mismatch", __func__);
 222         pw->pw_name = buffer_get_string(&m, NULL);
 223         pw->pw_passwd = buffer_get_string(&m, NULL);
 224         pw->pw_gecos = buffer_get_string(&m, NULL);
 225 #ifdef HAVE_PW_CLASS_IN_PASSWD
 226         pw->pw_class = buffer_get_string(&m, NULL);
 227 #endif
 228         pw->pw_dir = buffer_get_string(&m, NULL);
 229         pw->pw_shell = buffer_get_string(&m, NULL);
 230         buffer_free(&m);
 231
 232         return (pw);
 233 }
 234
 235 char *
 236 mm_auth2_read_banner(void)
 237 {
 238         Buffer m;
 239         char *banner;
 240
 241         debug3("%s entering", __func__);
 242
 243         buffer_init(&m);
 244         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTH2_READ_BANNER, &m);
 245         buffer_clear(&m);
 246
 247         mm_request_receive_expect(pmonitor->m_recvfd,
 248             MONITOR_ANS_AUTH2_READ_BANNER, &m);
 249         banner = buffer_get_string(&m, NULL);
 250         buffer_free(&m);
 251
 252         /* treat empty banner as missing banner */
 253         if (strlen(banner) == 0) {
 254                 xfree(banner);
 255                 banner = NULL;
 256         }
 257         return (banner);
 258 }
 259
 260 /* Inform the privileged process about service and style */
 261
 262 void
 263 mm_inform_authserv(char *service, char *style)
 264 {
 265         Buffer m;
 266
 267         debug3("%s entering", __func__);
 268
 269         buffer_init(&m);
 270         buffer_put_cstring(&m, service);
 271         buffer_put_cstring(&m, style ? style : "");
 272
 273         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHSERV, &m);
 274
 275         buffer_free(&m);
 276 }
 277
 278 /* Do the password authentication */
 279 int
 280 mm_auth_password(Authctxt *authctxt, char *password)
 281 {
 282         Buffer m;
 283         int authenticated = 0;
 284
 285         debug3("%s entering", __func__);
 286
 287         buffer_init(&m);
 288         buffer_put_cstring(&m, password);
 289         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHPASSWORD, &m);
 290
 291         debug3("%s: waiting for MONITOR_ANS_AUTHPASSWORD", __func__);
 292         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_AUTHPASSWORD, &m);
 293
 294         authenticated = buffer_get_int(&m);
 295
 296         buffer_free(&m);
 297
 298         debug3("%s: user %sauthenticated",
 299             __func__, authenticated ? "" : "not ");
 300         return (authenticated);
 301 }
 302
 303 int
 304 mm_user_key_allowed(struct passwd *pw, Key *key)
 305 {
 306         return (mm_key_allowed(MM_USERKEY, NULL, NULL, key));
 307 }
 308
 309 int
 310 mm_hostbased_key_allowed(struct passwd *pw, char *user, char *host,
 311     Key *key)
 312 {
 313         return (mm_key_allowed(MM_HOSTKEY, user, host, key));
 314 }
 315
 316 int
 317 mm_auth_rhosts_rsa_key_allowed(struct passwd *pw, char *user,
 318     char *host, Key *key)
 319 {
 320         int ret;
 321
 322         key->type = KEY_RSA; /* XXX hack for key_to_blob */
 323         ret = mm_key_allowed(MM_RSAHOSTKEY, user, host, key);
 324         key->type = KEY_RSA1;
 325         return (ret);
 326 }
 327
 328 static void
 329 mm_send_debug(Buffer *m)
 330 {
 331         char *msg;
 332
 333         while (buffer_len(m)) {
 334                 msg = buffer_get_string(m, NULL);
 335                 debug3("%s: Sending debug: %s", __func__, msg);
 336                 packet_send_debug("%s", msg);
 337                 xfree(msg);
 338         }
 339 }
 340
 341 int
 342 mm_key_allowed(enum mm_keytype type, char *user, char *host, Key *key)
 343 {
 344         Buffer m;
 345         u_char *blob;
 346         u_int len;
 347         int allowed = 0, have_forced = 0;
 348
 349         debug3("%s entering", __func__);
 350
 351         /* Convert the key to a blob and the pass it over */
 352         if (!key_to_blob(key, &blob, &len))
 353                 return (0);
 354
 355         buffer_init(&m);
 356         buffer_put_int(&m, type);
 357         buffer_put_cstring(&m, user ? user : "");
 358         buffer_put_cstring(&m, host ? host : "");
 359         buffer_put_string(&m, blob, len);
 360         xfree(blob);
 361
 362         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYALLOWED, &m);
 363
 364         debug3("%s: waiting for MONITOR_ANS_KEYALLOWED", __func__);
 365         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_KEYALLOWED, &m);
 366
 367         allowed = buffer_get_int(&m);
 368
 369         /* fake forced command */
 370         auth_clear_options();
 371         have_forced = buffer_get_int(&m);
 372         forced_command = have_forced ? xstrdup("true") : NULL;
 373
 374         /* Send potential debug messages */
 375         mm_send_debug(&m);
 376
 377         buffer_free(&m);
 378
 379         return (allowed);
 380 }
 381
 382 /*
 383  * This key verify needs to send the key type along, because the
 384  * privileged parent makes the decision if the key is allowed
 385  * for authentication.
 386  */
 387
 388 int
 389 mm_key_verify(Key *key, u_char *sig, u_int siglen, u_char *data, u_int datalen)
 390 {
 391         Buffer m;
 392         u_char *blob;
 393         u_int len;
 394         int verified = 0;
 395
 396         debug3("%s entering", __func__);
 397
 398         /* Convert the key to a blob and the pass it over */
 399         if (!key_to_blob(key, &blob, &len))
 400                 return (0);
 401
 402         buffer_init(&m);
 403         buffer_put_string(&m, blob, len);
 404         buffer_put_string(&m, sig, siglen);
 405         buffer_put_string(&m, data, datalen);
 406         xfree(blob);
 407
 408         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYVERIFY, &m);
 409
 410         debug3("%s: waiting for MONITOR_ANS_KEYVERIFY", __func__);
 411         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_KEYVERIFY, &m);
 412
 413         verified = buffer_get_int(&m);
 414
 415         buffer_free(&m);
 416
 417         return (verified);
 418 }
 419
 420 /* Export key state after authentication */
 421 Newkeys *
 422 mm_newkeys_from_blob(u_char *blob, int blen)
 423 {
 424         Buffer b;
 425         u_int len;
 426         Newkeys *newkey = NULL;
 427         Enc *enc;
 428         Mac *mac;
 429         Comp *comp;
 430
 431         debug3("%s: %p(%d)", __func__, blob, blen);
 432 #ifdef DEBUG_PK
 433         dump_base64(stderr, blob, blen);
 434 #endif
 435         buffer_init(&b);
 436         buffer_append(&b, blob, blen);
 437
 438         newkey = xmalloc(sizeof(*newkey));
 439         enc = &newkey->enc;
 440         mac = &newkey->mac;
 441         comp = &newkey->comp;
 442
 443         /* Enc structure */
 444         enc->name = buffer_get_string(&b, NULL);
 445         buffer_get(&b, &enc->cipher, sizeof(enc->cipher));
 446         enc->enabled = buffer_get_int(&b);
 447         enc->block_size = buffer_get_int(&b);
 448         enc->key = buffer_get_string(&b, &enc->key_len);
 449         enc->iv = buffer_get_string(&b, &len);
 450         if (len != enc->block_size)
 451                 fatal("%s: bad ivlen: expected %u != %u", __func__,
 452                     enc->block_size, len);
 453
 454         if (enc->name == NULL || cipher_by_name(enc->name) != enc->cipher)
 455                 fatal("%s: bad cipher name %s or pointer %p", __func__,
 456                     enc->name, enc->cipher);
 457
 458         /* Mac structure */
 459         mac->name = buffer_get_string(&b, NULL);
 460         if (mac->name == NULL || mac_init(mac, mac->name) == -1)
 461                 fatal("%s: can not init mac %s", __func__, mac->name);
 462         mac->enabled = buffer_get_int(&b);
 463         mac->key = buffer_get_string(&b, &len);
 464         if (len > mac->key_len)
 465                 fatal("%s: bad mac key length: %u > %d", __func__, len,
 466                     mac->key_len);
 467         mac->key_len = len;
 468
 469         /* Comp structure */
 470         comp->type = buffer_get_int(&b);
 471         comp->enabled = buffer_get_int(&b);
 472         comp->name = buffer_get_string(&b, NULL);
 473
 474         len = buffer_len(&b);
 475         if (len != 0)
 476                 error("newkeys_from_blob: remaining bytes in blob %u", len);
 477         buffer_free(&b);
 478         return (newkey);
 479 }
 480
 481 int
 482 mm_newkeys_to_blob(int mode, u_char **blobp, u_int *lenp)
 483 {
 484         Buffer b;
 485         int len;
 486         Enc *enc;
 487         Mac *mac;
 488         Comp *comp;
 489         Newkeys *newkey = newkeys[mode];
 490
 491         debug3("%s: converting %p", __func__, newkey);
 492
 493         if (newkey == NULL) {
 494                 error("%s: newkey == NULL", __func__);
 495                 return 0;
 496         }
 497         enc = &newkey->enc;
 498         mac = &newkey->mac;
 499         comp = &newkey->comp;
 500
 501         buffer_init(&b);
 502         /* Enc structure */
 503         buffer_put_cstring(&b, enc->name);
 504         /* The cipher struct is constant and shared, you export pointer */
 505         buffer_append(&b, &enc->cipher, sizeof(enc->cipher));
 506         buffer_put_int(&b, enc->enabled);
 507         buffer_put_int(&b, enc->block_size);
 508         buffer_put_string(&b, enc->key, enc->key_len);
 509         packet_get_keyiv(mode, enc->iv, enc->block_size);
 510         buffer_put_string(&b, enc->iv, enc->block_size);
 511
 512         /* Mac structure */
 513         buffer_put_cstring(&b, mac->name);
 514         buffer_put_int(&b, mac->enabled);
 515         buffer_put_string(&b, mac->key, mac->key_len);
 516
 517         /* Comp structure */
 518         buffer_put_int(&b, comp->type);
 519         buffer_put_int(&b, comp->enabled);
 520         buffer_put_cstring(&b, comp->name);
 521
 522         len = buffer_len(&b);
 523         if (lenp != NULL)
 524                 *lenp = len;
 525         if (blobp != NULL) {
 526                 *blobp = xmalloc(len);
 527                 memcpy(*blobp, buffer_ptr(&b), len);
 528         }
 529         memset(buffer_ptr(&b), 0, len);
 530         buffer_free(&b);
 531         return len;
 532 }
 533
 534 static void
 535 mm_send_kex(Buffer *m, Kex *kex)
 536 {
 537         buffer_put_string(m, kex->session_id, kex->session_id_len);
 538         buffer_put_int(m, kex->we_need);
 539         buffer_put_int(m, kex->hostkey_type);
 540         buffer_put_int(m, kex->kex_type);
 541         buffer_put_string(m, buffer_ptr(&kex->my), buffer_len(&kex->my));
 542         buffer_put_string(m, buffer_ptr(&kex->peer), buffer_len(&kex->peer));
 543         buffer_put_int(m, kex->flags);
 544         buffer_put_cstring(m, kex->client_version_string);
 545         buffer_put_cstring(m, kex->server_version_string);
 546 }
 547
 548 void
 549 mm_send_keystate(struct monitor *monitor)
 550 {
 551         Buffer m;
 552         u_char *blob, *p;
 553         u_int bloblen, plen;
 554         u_int32_t seqnr, packets;
 555         u_int64_t blocks;
 556
 557         buffer_init(&m);
 558
 559         if (!compat20) {
 560                 u_char iv[24];
 561                 u_char *key;
 562                 u_int ivlen, keylen;
 563
 564                 buffer_put_int(&m, packet_get_protocol_flags());
 565
 566                 buffer_put_int(&m, packet_get_ssh1_cipher());
 567
 568                 debug3("%s: Sending ssh1 KEY+IV", __func__);
 569                 keylen = packet_get_encryption_key(NULL);
 570                 key = xmalloc(keylen+1);        /* add 1 if keylen == 0 */
 571                 keylen = packet_get_encryption_key(key);
 572                 buffer_put_string(&m, key, keylen);
 573                 memset(key, 0, keylen);
 574                 xfree(key);
 575
 576                 ivlen = packet_get_keyiv_len(MODE_OUT);
 577                 packet_get_keyiv(MODE_OUT, iv, ivlen);
 578                 buffer_put_string(&m, iv, ivlen);
 579                 ivlen = packet_get_keyiv_len(MODE_OUT);
 580                 packet_get_keyiv(MODE_IN, iv, ivlen);
 581                 buffer_put_string(&m, iv, ivlen);
 582                 goto skip;
 583         } else {
 584                 /* Kex for rekeying */
 585                 mm_send_kex(&m, *monitor->m_pkex);
 586         }
 587
 588         debug3("%s: Sending new keys: %p %p",
 589             __func__, newkeys[MODE_OUT], newkeys[MODE_IN]);
 590
 591         /* Keys from Kex */
 592         if (!mm_newkeys_to_blob(MODE_OUT, &blob, &bloblen))
 593                 fatal("%s: conversion of newkeys failed", __func__);
 594
 595         buffer_put_string(&m, blob, bloblen);
 596         xfree(blob);
 597
 598         if (!mm_newkeys_to_blob(MODE_IN, &blob, &bloblen))
 599                 fatal("%s: conversion of newkeys failed", __func__);
 600
 601         buffer_put_string(&m, blob, bloblen);
 602         xfree(blob);
 603
 604         packet_get_state(MODE_OUT, &seqnr, &blocks, &packets);
 605         buffer_put_int(&m, seqnr);
 606         buffer_put_int64(&m, blocks);
 607         buffer_put_int(&m, packets);
 608         packet_get_state(MODE_IN, &seqnr, &blocks, &packets);
 609         buffer_put_int(&m, seqnr);
 610         buffer_put_int64(&m, blocks);
 611         buffer_put_int(&m, packets);
 612
 613         debug3("%s: New keys have been sent", __func__);
 614  skip:
 615         /* More key context */
 616         plen = packet_get_keycontext(MODE_OUT, NULL);
 617         p = xmalloc(plen+1);
 618         packet_get_keycontext(MODE_OUT, p);
 619         buffer_put_string(&m, p, plen);
 620         xfree(p);
 621
 622         plen = packet_get_keycontext(MODE_IN, NULL);
 623         p = xmalloc(plen+1);
 624         packet_get_keycontext(MODE_IN, p);
 625         buffer_put_string(&m, p, plen);
 626         xfree(p);
 627
 628         /* Compression state */
 629         debug3("%s: Sending compression state", __func__);
 630         buffer_put_string(&m, &outgoing_stream, sizeof(outgoing_stream));
 631         buffer_put_string(&m, &incoming_stream, sizeof(incoming_stream));
 632
 633         /* Network I/O buffers */
 634         buffer_put_string(&m, buffer_ptr(&input), buffer_len(&input));
 635         buffer_put_string(&m, buffer_ptr(&output), buffer_len(&output));
 636
 637         mm_request_send(monitor->m_recvfd, MONITOR_REQ_KEYEXPORT, &m);
 638         debug3("%s: Finished sending state", __func__);
 639
 640         buffer_free(&m);
 641 }
 642
 643 int
 644 mm_pty_allocate(int *ptyfd, int *ttyfd, char *namebuf, int namebuflen)
 645 {
 646         Buffer m;
 647         char *p, *msg;
 648         int success = 0;
 649
 650         buffer_init(&m);
 651         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTY, &m);
 652
 653         debug3("%s: waiting for MONITOR_ANS_PTY", __func__);
 654         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PTY, &m);
 655
 656         success = buffer_get_int(&m);
 657         if (success == 0) {
 658                 debug3("%s: pty alloc failed", __func__);
 659                 buffer_free(&m);
 660                 return (0);
 661         }
 662         p = buffer_get_string(&m, NULL);
 663         msg = buffer_get_string(&m, NULL);
 664         buffer_free(&m);
 665
 666         strlcpy(namebuf, p, namebuflen); /* Possible truncation */
 667         xfree(p);
 668
 669         buffer_append(&loginmsg, msg, strlen(msg));
 670         xfree(msg);
 671
 672         *ptyfd = mm_receive_fd(pmonitor->m_recvfd);
 673         *ttyfd = mm_receive_fd(pmonitor->m_recvfd);
 674
 675         /* Success */
 676         return (1);
 677 }
 678
 679 void
 680 mm_session_pty_cleanup2(Session *s)
 681 {
 682         Buffer m;
 683
 684         if (s->ttyfd == -1)
 685                 return;
 686         buffer_init(&m);
 687         buffer_put_cstring(&m, s->tty);
 688         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTYCLEANUP, &m);
 689         buffer_free(&m);
 690
 691         /* closed dup'ed master */
 692         if (close(s->ptymaster) < 0)
 693                 error("close(s->ptymaster): %s", strerror(errno));
 694
 695         /* unlink pty from session */
 696         s->ttyfd = -1;
 697 }
 698
 699 #ifdef USE_PAM
 700 void
 701 mm_start_pam(Authctxt *authctxt)
 702 {
 703         Buffer m;
 704
 705         debug3("%s entering", __func__);
 706         if (!options.use_pam)
 707                 fatal("UsePAM=no, but ended up in %s anyway", __func__);
 708
 709         buffer_init(&m);
 710         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_START, &m);
 711
 712         buffer_free(&m);
 713 }
 714
 715 u_int
 716 mm_do_pam_account(void)
 717 {
 718         Buffer m;
 719         u_int ret;
 720         char *msg;
 721
 722         debug3("%s entering", __func__);
 723         if (!options.use_pam)
 724                 fatal("UsePAM=no, but ended up in %s anyway", __func__);
 725
 726         buffer_init(&m);
 727         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_ACCOUNT, &m);
 728
 729         mm_request_receive_expect(pmonitor->m_recvfd,
 730             MONITOR_ANS_PAM_ACCOUNT, &m);
 731         ret = buffer_get_int(&m);
 732         msg = buffer_get_string(&m, NULL);
 733         buffer_append(&loginmsg, msg, strlen(msg));
 734         xfree(msg);
 735
 736         buffer_free(&m);
 737
 738         debug3("%s returning %d", __func__, ret);
 739
 740         return (ret);
 741 }
 742
 743 void *
 744 mm_sshpam_init_ctx(Authctxt *authctxt)
 745 {
 746         Buffer m;
 747         int success;
 748
 749         debug3("%s", __func__);
 750         buffer_init(&m);
 751         buffer_put_cstring(&m, authctxt->user);
 752         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_INIT_CTX, &m);
 753         debug3("%s: waiting for MONITOR_ANS_PAM_INIT_CTX", __func__);
 754         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_INIT_CTX, &m);
 755         success = buffer_get_int(&m);
 756         if (success == 0) {
 757                 debug3("%s: pam_init_ctx failed", __func__);
 758                 buffer_free(&m);
 759                 return (NULL);
 760         }
 761         buffer_free(&m);
 762         return (authctxt);
 763 }
 764
 765 int
 766 mm_sshpam_query(void *ctx, char **name, char **info,
 767     u_int *num, char ***prompts, u_int **echo_on)
 768 {
 769         Buffer m;
 770         int i, ret;
 771
 772         debug3("%s", __func__);
 773         buffer_init(&m);
 774         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_QUERY, &m);
 775         debug3("%s: waiting for MONITOR_ANS_PAM_QUERY", __func__);
 776         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_QUERY, &m);
 777         ret = buffer_get_int(&m);
 778         debug3("%s: pam_query returned %d", __func__, ret);
 779         *name = buffer_get_string(&m, NULL);
 780         *info = buffer_get_string(&m, NULL);
 781         *num = buffer_get_int(&m);
 782         *prompts = xmalloc((*num + 1) * sizeof(char *));
 783         *echo_on = xmalloc((*num + 1) * sizeof(u_int));
 784         for (i = 0; i < *num; ++i) {
 785                 (*prompts)[i] = buffer_get_string(&m, NULL);
 786                 (*echo_on)[i] = buffer_get_int(&m);
 787         }
 788         buffer_free(&m);
 789         return (ret);
 790 }
 791
 792 int
 793 mm_sshpam_respond(void *ctx, u_int num, char **resp)
 794 {
 795         Buffer m;
 796         int i, ret;
 797
 798         debug3("%s", __func__);
 799         buffer_init(&m);
 800         buffer_put_int(&m, num);
 801         for (i = 0; i < num; ++i)
 802                 buffer_put_cstring(&m, resp[i]);
 803         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_RESPOND, &m);
 804         debug3("%s: waiting for MONITOR_ANS_PAM_RESPOND", __func__);
 805         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_RESPOND, &m);
 806         ret = buffer_get_int(&m);
 807         debug3("%s: pam_respond returned %d", __func__, ret);
 808         buffer_free(&m);
 809         return (ret);
 810 }
 811
 812 void
 813 mm_sshpam_free_ctx(void *ctxtp)
 814 {
 815         Buffer m;
 816
 817         debug3("%s", __func__);
 818         buffer_init(&m);
 819         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_FREE_CTX, &m);
 820         debug3("%s: waiting for MONITOR_ANS_PAM_FREE_CTX", __func__);
 821         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_FREE_CTX, &m);
 822         buffer_free(&m);
 823 }
 824 #endif /* USE_PAM */
 825
 826 /* Request process termination */
 827
 828 void
 829 mm_terminate(void)
 830 {
 831         Buffer m;
 832
 833         buffer_init(&m);
 834         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_TERM, &m);
 835         buffer_free(&m);
 836 }
 837
 838 int
 839 mm_ssh1_session_key(BIGNUM *num)
 840 {
 841         int rsafail;
 842         Buffer m;
 843
 844         buffer_init(&m);
 845         buffer_put_bignum2(&m, num);
 846         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SESSKEY, &m);
 847
 848         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SESSKEY, &m);
 849
 850         rsafail = buffer_get_int(&m);
 851         buffer_get_bignum2(&m, num);
 852
 853         buffer_free(&m);
 854
 855         return (rsafail);
 856 }
 857
 858 static void
 859 mm_chall_setup(char **name, char **infotxt, u_int *numprompts,
 860     char ***prompts, u_int **echo_on)
 861 {
 862         *name = xstrdup("");
 863         *infotxt = xstrdup("");
 864         *numprompts = 1;
 865         *prompts = xmalloc(*numprompts * sizeof(char *));
 866         *echo_on = xmalloc(*numprompts * sizeof(u_int));
 867         (*echo_on)[0] = 0;
 868 }
 869
 870 int
 871 mm_bsdauth_query(void *ctx, char **name, char **infotxt,
 872    u_int *numprompts, char ***prompts, u_int **echo_on)
 873 {
 874         Buffer m;
 875         u_int success;
 876         char *challenge;
 877
 878         debug3("%s: entering", __func__);
 879
 880         buffer_init(&m);
 881         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHQUERY, &m);
 882
 883         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_BSDAUTHQUERY,
 884             &m);
 885         success = buffer_get_int(&m);
 886         if (success == 0) {
 887                 debug3("%s: no challenge", __func__);
 888                 buffer_free(&m);
 889                 return (-1);
 890         }
 891
 892         /* Get the challenge, and format the response */
 893         challenge  = buffer_get_string(&m, NULL);
 894         buffer_free(&m);
 895
 896         mm_chall_setup(name, infotxt, numprompts, prompts, echo_on);
 897         (*prompts)[0] = challenge;
 898
 899         debug3("%s: received challenge: %s", __func__, challenge);
 900
 901         return (0);
 902 }
 903
 904 int
 905 mm_bsdauth_respond(void *ctx, u_int numresponses, char **responses)
 906 {
 907         Buffer m;
 908         int authok;
 909
 910         debug3("%s: entering", __func__);
 911         if (numresponses != 1)
 912                 return (-1);
 913
 914         buffer_init(&m);
 915         buffer_put_cstring(&m, responses[0]);
 916         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHRESPOND, &m);
 917
 918         mm_request_receive_expect(pmonitor->m_recvfd,
 919             MONITOR_ANS_BSDAUTHRESPOND, &m);
 920
 921         authok = buffer_get_int(&m);
 922         buffer_free(&m);
 923
 924         return ((authok == 0) ? -1 : 0);
 925 }
 926
 927 #ifdef SKEY
 928 int
 929 mm_skey_query(void *ctx, char **name, char **infotxt,
 930    u_int *numprompts, char ***prompts, u_int **echo_on)
 931 {
 932         Buffer m;
 933         int len;
 934         u_int success;
 935         char *p, *challenge;
 936
 937         debug3("%s: entering", __func__);
 938
 939         buffer_init(&m);
 940         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SKEYQUERY, &m);
 941
 942         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SKEYQUERY,
 943             &m);
 944         success = buffer_get_int(&m);
 945         if (success == 0) {
 946                 debug3("%s: no challenge", __func__);
 947                 buffer_free(&m);
 948                 return (-1);
 949         }
 950
 951         /* Get the challenge, and format the response */
 952         challenge  = buffer_get_string(&m, NULL);
 953         buffer_free(&m);
 954
 955         debug3("%s: received challenge: %s", __func__, challenge);
 956
 957         mm_chall_setup(name, infotxt, numprompts, prompts, echo_on);
 958
 959         len = strlen(challenge) + strlen(SKEY_PROMPT) + 1;
 960         p = xmalloc(len);
 961         strlcpy(p, challenge, len);
 962         strlcat(p, SKEY_PROMPT, len);
 963         (*prompts)[0] = p;
 964         xfree(challenge);
 965
 966         return (0);
 967 }
 968
 969 int
 970 mm_skey_respond(void *ctx, u_int numresponses, char **responses)
 971 {
 972         Buffer m;
 973         int authok;
 974
 975         debug3("%s: entering", __func__);
 976         if (numresponses != 1)
 977                 return (-1);
 978
 979         buffer_init(&m);
 980         buffer_put_cstring(&m, responses[0]);
 981         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SKEYRESPOND, &m);
 982
 983         mm_request_receive_expect(pmonitor->m_recvfd,
 984             MONITOR_ANS_SKEYRESPOND, &m);
 985
 986         authok = buffer_get_int(&m);
 987         buffer_free(&m);
 988
 989         return ((authok == 0) ? -1 : 0);
 990 }
 991 #endif /* SKEY */
 992
 993 void
 994 mm_ssh1_session_id(u_char session_id[16])
 995 {
 996         Buffer m;
 997         int i;
 998
 999         debug3("%s entering", __func__);
1000
1001         buffer_init(&m);
1002         for (i = 0; i < 16; i++)
1003                 buffer_put_char(&m, session_id[i]);
1004
1005         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SESSID, &m);
1006         buffer_free(&m);
1007 }
1008
1009 int
1010 mm_auth_rsa_key_allowed(struct passwd *pw, BIGNUM *client_n, Key **rkey)
1011 {
1012         Buffer m;
1013         Key *key;
1014         u_char *blob;
1015         u_int blen;
1016         int allowed = 0, have_forced = 0;
1017
1018         debug3("%s entering", __func__);
1019
1020         buffer_init(&m);
1021         buffer_put_bignum2(&m, client_n);
1022
1023         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSAKEYALLOWED, &m);
1024         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSAKEYALLOWED, &m);
1025
1026         allowed = buffer_get_int(&m);
1027
1028         /* fake forced command */
1029         auth_clear_options();
1030         have_forced = buffer_get_int(&m);
1031         forced_command = have_forced ? xstrdup("true") : NULL;
1032
1033         if (allowed && rkey != NULL) {
1034                 blob = buffer_get_string(&m, &blen);
1035                 if ((key = key_from_blob(blob, blen)) == NULL)
1036                         fatal("%s: key_from_blob failed", __func__);
1037                 *rkey = key;
1038                 xfree(blob);
1039         }
1040         mm_send_debug(&m);
1041         buffer_free(&m);
1042
1043         return (allowed);
1044 }
1045
1046 BIGNUM *
1047 mm_auth_rsa_generate_challenge(Key *key)
1048 {
1049         Buffer m;
1050         BIGNUM *challenge;
1051         u_char *blob;
1052         u_int blen;
1053
1054         debug3("%s entering", __func__);
1055
1056         if ((challenge = BN_new()) == NULL)
1057                 fatal("%s: BN_new failed", __func__);
1058
1059         key->type = KEY_RSA;    /* XXX cheat for key_to_blob */
1060         if (key_to_blob(key, &blob, &blen) == 0)
1061                 fatal("%s: key_to_blob failed", __func__);
1062         key->type = KEY_RSA1;
1063
1064         buffer_init(&m);
1065         buffer_put_string(&m, blob, blen);
1066         xfree(blob);
1067
1068         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSACHALLENGE, &m);
1069         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSACHALLENGE, &m);
1070
1071         buffer_get_bignum2(&m, challenge);
1072         buffer_free(&m);
1073
1074         return (challenge);
1075 }
1076
1077 int
1078 mm_auth_rsa_verify_response(Key *key, BIGNUM *p, u_char response[16])
1079 {
1080         Buffer m;
1081         u_char *blob;
1082         u_int blen;
1083         int success = 0;
1084
1085         debug3("%s entering", __func__);
1086
1087         key->type = KEY_RSA;    /* XXX cheat for key_to_blob */
1088         if (key_to_blob(key, &blob, &blen) == 0)
1089                 fatal("%s: key_to_blob failed", __func__);
1090         key->type = KEY_RSA1;
1091
1092         buffer_init(&m);
1093         buffer_put_string(&m, blob, blen);
1094         buffer_put_string(&m, response, 16);
1095         xfree(blob);
1096
1097         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSARESPONSE, &m);
1098         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSARESPONSE, &m);
1099
1100         success = buffer_get_int(&m);
1101         buffer_free(&m);
1102
1103         return (success);
1104 }
1105
1106 #ifdef SSH_AUDIT_EVENTS
1107 void
1108 mm_audit_event(ssh_audit_event_t event)
1109 {
1110         Buffer m;
1111
1112         debug3("%s entering", __func__);
1113
1114         buffer_init(&m);
1115         buffer_put_int(&m, event);
1116
1117         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUDIT_EVENT, &m);
1118         buffer_free(&m);
1119 }
1120
1121 void
1122 mm_audit_run_command(const char *command)
1123 {
1124         Buffer m;
1125
1126         debug3("%s entering command %s", __func__, command);
1127
1128         buffer_init(&m);
1129         buffer_put_cstring(&m, command);
1130
1131         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUDIT_COMMAND, &m);
1132         buffer_free(&m);
1133 }
1134 #endif /* SSH_AUDIT_EVENTS */
1135
1136 #ifdef GSSAPI
1137 OM_uint32
1138 mm_ssh_gssapi_server_ctx(Gssctxt **ctx, gss_OID goid)
1139 {
1140         Buffer m;
1141         OM_uint32 major;
1142
1143         /* Client doesn't get to see the context */
1144         *ctx = NULL;
1145
1146         buffer_init(&m);
1147         buffer_put_string(&m, goid->elements, goid->length);
1148
1149         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSETUP, &m);
1150         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSETUP, &m);
1151
1152         major = buffer_get_int(&m);
1153
1154         buffer_free(&m);
1155         return (major);
1156 }
1157
1158 OM_uint32
1159 mm_ssh_gssapi_accept_ctx(Gssctxt *ctx, gss_buffer_desc *in,
1160     gss_buffer_desc *out, OM_uint32 *flags)
1161 {
1162         Buffer m;
1163         OM_uint32 major;
1164         u_int len;
1165
1166         buffer_init(&m);
1167         buffer_put_string(&m, in->value, in->length);
1168
1169         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSTEP, &m);
1170         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSTEP, &m);
1171
1172         major = buffer_get_int(&m);
1173         out->value = buffer_get_string(&m, &len);
1174         out->length = len;
1175         if (flags)
1176                 *flags = buffer_get_int(&m);
1177
1178         buffer_free(&m);
1179
1180         return (major);
1181 }
1182
1183 OM_uint32
1184 mm_ssh_gssapi_checkmic(Gssctxt *ctx, gss_buffer_t gssbuf, gss_buffer_t gssmic)
1185 {
1186         Buffer m;
1187         OM_uint32 major;
1188
1189         buffer_init(&m);
1190         buffer_put_string(&m, gssbuf->value, gssbuf->length);
1191         buffer_put_string(&m, gssmic->value, gssmic->length);
1192
1193         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSCHECKMIC, &m);
1194         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSCHECKMIC,
1195             &m);
1196
1197         major = buffer_get_int(&m);
1198         buffer_free(&m);
1199         return(major);
1200 }
1201
1202 int
1203 mm_ssh_gssapi_userok(char *user)
1204 {
1205         Buffer m;
1206         int authenticated = 0;
1207
1208         buffer_init(&m);
1209
1210         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSUSEROK, &m);
1211         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSUSEROK,
1212                                   &m);
1213
1214         authenticated = buffer_get_int(&m);
1215
1216         buffer_free(&m);
1217         debug3("%s: user %sauthenticated",__func__, authenticated ? "" : "not ");
1218         return (authenticated);
1219 }
1220 #endif /* GSSAPI */