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 1.40 2005/05/24 17:32:43 avsm 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: %s", __func__, strerror(errno));
  99         if (atomicio(vwrite, sock, buffer_ptr(m), mlen) != mlen)
 100                 fatal("%s: write: %s", __func__, strerror(errno));
 101 }
 102
 103 void
 104 mm_request_receive(int sock, Buffer *m)
 105 {
 106         u_char buf[4];
 107         u_int msg_len;
 108
 109         debug3("%s entering", __func__);
 110
 111         if (atomicio(read, sock, buf, sizeof(buf)) != sizeof(buf)) {
 112                 if (errno == EPIPE)
 113                         cleanup_exit(255);
 114                 fatal("%s: read: %s", __func__, strerror(errno));
 115         }
 116         msg_len = GET_32BIT(buf);
 117         if (msg_len > 256 * 1024)
 118                 fatal("%s: read: bad msg_len %d", __func__, msg_len);
 119         buffer_clear(m);
 120         buffer_append_space(m, msg_len);
 121         if (atomicio(read, sock, buffer_ptr(m), msg_len) != msg_len)
 122                 fatal("%s: read: %s", __func__, strerror(errno));
 123 }
 124
 125 void
 126 mm_request_receive_expect(int sock, enum monitor_reqtype type, Buffer *m)
 127 {
 128         u_char rtype;
 129
 130         debug3("%s entering: type %d", __func__, type);
 131
 132         mm_request_receive(sock, m);
 133         rtype = buffer_get_char(m);
 134         if (rtype != type)
 135                 fatal("%s: read: rtype %d != type %d", __func__,
 136                     rtype, type);
 137 }
 138
 139 DH *
 140 mm_choose_dh(int min, int nbits, int max)
 141 {
 142         BIGNUM *p, *g;
 143         int success = 0;
 144         Buffer m;
 145
 146         buffer_init(&m);
 147         buffer_put_int(&m, min);
 148         buffer_put_int(&m, nbits);
 149         buffer_put_int(&m, max);
 150
 151         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_MODULI, &m);
 152
 153         debug3("%s: waiting for MONITOR_ANS_MODULI", __func__);
 154         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_MODULI, &m);
 155
 156         success = buffer_get_char(&m);
 157         if (success == 0)
 158                 fatal("%s: MONITOR_ANS_MODULI failed", __func__);
 159
 160         if ((p = BN_new()) == NULL)
 161                 fatal("%s: BN_new failed", __func__);
 162         if ((g = BN_new()) == NULL)
 163                 fatal("%s: BN_new failed", __func__);
 164         buffer_get_bignum2(&m, p);
 165         buffer_get_bignum2(&m, g);
 166
 167         debug3("%s: remaining %d", __func__, buffer_len(&m));
 168         buffer_free(&m);
 169
 170         return (dh_new_group(g, p));
 171 }
 172
 173 int
 174 mm_key_sign(Key *key, u_char **sigp, u_int *lenp, u_char *data, u_int datalen)
 175 {
 176         Kex *kex = *pmonitor->m_pkex;
 177         Buffer m;
 178
 179         debug3("%s entering", __func__);
 180
 181         buffer_init(&m);
 182         buffer_put_int(&m, kex->host_key_index(key));
 183         buffer_put_string(&m, data, datalen);
 184
 185         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SIGN, &m);
 186
 187         debug3("%s: waiting for MONITOR_ANS_SIGN", __func__);
 188         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SIGN, &m);
 189         *sigp  = buffer_get_string(&m, lenp);
 190         buffer_free(&m);
 191
 192         return (0);
 193 }
 194
 195 struct passwd *
 196 mm_getpwnamallow(const char *username)
 197 {
 198         Buffer m;
 199         struct passwd *pw;
 200         u_int pwlen;
 201
 202         debug3("%s entering", __func__);
 203
 204         buffer_init(&m);
 205         buffer_put_cstring(&m, username);
 206
 207         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PWNAM, &m);
 208
 209         debug3("%s: waiting for MONITOR_ANS_PWNAM", __func__);
 210         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PWNAM, &m);
 211
 212         if (buffer_get_char(&m) == 0) {
 213                 buffer_free(&m);
 214                 return (NULL);
 215         }
 216         pw = buffer_get_string(&m, &pwlen);
 217         if (pwlen != sizeof(struct passwd))
 218                 fatal("%s: struct passwd size mismatch", __func__);
 219         pw->pw_name = buffer_get_string(&m, NULL);
 220         pw->pw_passwd = buffer_get_string(&m, NULL);
 221         pw->pw_gecos = buffer_get_string(&m, NULL);
 222 #ifdef HAVE_PW_CLASS_IN_PASSWD
 223         pw->pw_class = buffer_get_string(&m, NULL);
 224 #endif
 225         pw->pw_dir = buffer_get_string(&m, NULL);
 226         pw->pw_shell = buffer_get_string(&m, NULL);
 227         buffer_free(&m);
 228
 229         return (pw);
 230 }
 231
 232 char *
 233 mm_auth2_read_banner(void)
 234 {
 235         Buffer m;
 236         char *banner;
 237
 238         debug3("%s entering", __func__);
 239
 240         buffer_init(&m);
 241         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTH2_READ_BANNER, &m);
 242         buffer_clear(&m);
 243
 244         mm_request_receive_expect(pmonitor->m_recvfd,
 245             MONITOR_ANS_AUTH2_READ_BANNER, &m);
 246         banner = buffer_get_string(&m, NULL);
 247         buffer_free(&m);
 248
 249         /* treat empty banner as missing banner */
 250         if (strlen(banner) == 0) {
 251                 xfree(banner);
 252                 banner = NULL;
 253         }
 254         return (banner);
 255 }
 256
 257 /* Inform the privileged process about service and style */
 258
 259 void
 260 mm_inform_authserv(char *service, char *style)
 261 {
 262         Buffer m;
 263
 264         debug3("%s entering", __func__);
 265
 266         buffer_init(&m);
 267         buffer_put_cstring(&m, service);
 268         buffer_put_cstring(&m, style ? style : "");
 269
 270         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHSERV, &m);
 271
 272         buffer_free(&m);
 273 }
 274
 275 /* Do the password authentication */
 276 int
 277 mm_auth_password(Authctxt *authctxt, char *password)
 278 {
 279         Buffer m;
 280         int authenticated = 0;
 281
 282         debug3("%s entering", __func__);
 283
 284         buffer_init(&m);
 285         buffer_put_cstring(&m, password);
 286         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHPASSWORD, &m);
 287
 288         debug3("%s: waiting for MONITOR_ANS_AUTHPASSWORD", __func__);
 289         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_AUTHPASSWORD, &m);
 290
 291         authenticated = buffer_get_int(&m);
 292
 293         buffer_free(&m);
 294
 295         debug3("%s: user %sauthenticated",
 296             __func__, authenticated ? "" : "not ");
 297         return (authenticated);
 298 }
 299
 300 int
 301 mm_user_key_allowed(struct passwd *pw, Key *key)
 302 {
 303         return (mm_key_allowed(MM_USERKEY, NULL, NULL, key));
 304 }
 305
 306 int
 307 mm_hostbased_key_allowed(struct passwd *pw, char *user, char *host,
 308     Key *key)
 309 {
 310         return (mm_key_allowed(MM_HOSTKEY, user, host, key));
 311 }
 312
 313 int
 314 mm_auth_rhosts_rsa_key_allowed(struct passwd *pw, char *user,
 315     char *host, Key *key)
 316 {
 317         int ret;
 318
 319         key->type = KEY_RSA; /* XXX hack for key_to_blob */
 320         ret = mm_key_allowed(MM_RSAHOSTKEY, user, host, key);
 321         key->type = KEY_RSA1;
 322         return (ret);
 323 }
 324
 325 static void
 326 mm_send_debug(Buffer *m)
 327 {
 328         char *msg;
 329
 330         while (buffer_len(m)) {
 331                 msg = buffer_get_string(m, NULL);
 332                 debug3("%s: Sending debug: %s", __func__, msg);
 333                 packet_send_debug("%s", msg);
 334                 xfree(msg);
 335         }
 336 }
 337
 338 int
 339 mm_key_allowed(enum mm_keytype type, char *user, char *host, Key *key)
 340 {
 341         Buffer m;
 342         u_char *blob;
 343         u_int len;
 344         int allowed = 0, have_forced = 0;
 345
 346         debug3("%s entering", __func__);
 347
 348         /* Convert the key to a blob and the pass it over */
 349         if (!key_to_blob(key, &blob, &len))
 350                 return (0);
 351
 352         buffer_init(&m);
 353         buffer_put_int(&m, type);
 354         buffer_put_cstring(&m, user ? user : "");
 355         buffer_put_cstring(&m, host ? host : "");
 356         buffer_put_string(&m, blob, len);
 357         xfree(blob);
 358
 359         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYALLOWED, &m);
 360
 361         debug3("%s: waiting for MONITOR_ANS_KEYALLOWED", __func__);
 362         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_KEYALLOWED, &m);
 363
 364         allowed = buffer_get_int(&m);
 365
 366         /* fake forced command */
 367         auth_clear_options();
 368         have_forced = buffer_get_int(&m);
 369         forced_command = have_forced ? xstrdup("true") : NULL;
 370
 371         /* Send potential debug messages */
 372         mm_send_debug(&m);
 373
 374         buffer_free(&m);
 375
 376         return (allowed);
 377 }
 378
 379 /*
 380  * This key verify needs to send the key type along, because the
 381  * privileged parent makes the decision if the key is allowed
 382  * for authentication.
 383  */
 384
 385 int
 386 mm_key_verify(Key *key, u_char *sig, u_int siglen, u_char *data, u_int datalen)
 387 {
 388         Buffer m;
 389         u_char *blob;
 390         u_int len;
 391         int verified = 0;
 392
 393         debug3("%s entering", __func__);
 394
 395         /* Convert the key to a blob and the pass it over */
 396         if (!key_to_blob(key, &blob, &len))
 397                 return (0);
 398
 399         buffer_init(&m);
 400         buffer_put_string(&m, blob, len);
 401         buffer_put_string(&m, sig, siglen);
 402         buffer_put_string(&m, data, datalen);
 403         xfree(blob);
 404
 405         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYVERIFY, &m);
 406
 407         debug3("%s: waiting for MONITOR_ANS_KEYVERIFY", __func__);
 408         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_KEYVERIFY, &m);
 409
 410         verified = buffer_get_int(&m);
 411
 412         buffer_free(&m);
 413
 414         return (verified);
 415 }
 416
 417 /* Export key state after authentication */
 418 Newkeys *
 419 mm_newkeys_from_blob(u_char *blob, int blen)
 420 {
 421         Buffer b;
 422         u_int len;
 423         Newkeys *newkey = NULL;
 424         Enc *enc;
 425         Mac *mac;
 426         Comp *comp;
 427
 428         debug3("%s: %p(%d)", __func__, blob, blen);
 429 #ifdef DEBUG_PK
 430         dump_base64(stderr, blob, blen);
 431 #endif
 432         buffer_init(&b);
 433         buffer_append(&b, blob, blen);
 434
 435         newkey = xmalloc(sizeof(*newkey));
 436         enc = &newkey->enc;
 437         mac = &newkey->mac;
 438         comp = &newkey->comp;
 439
 440         /* Enc structure */
 441         enc->name = buffer_get_string(&b, NULL);
 442         buffer_get(&b, &enc->cipher, sizeof(enc->cipher));
 443         enc->enabled = buffer_get_int(&b);
 444         enc->block_size = buffer_get_int(&b);
 445         enc->key = buffer_get_string(&b, &enc->key_len);
 446         enc->iv = buffer_get_string(&b, &len);
 447         if (len != enc->block_size)
 448                 fatal("%s: bad ivlen: expected %u != %u", __func__,
 449                     enc->block_size, len);
 450
 451         if (enc->name == NULL || cipher_by_name(enc->name) != enc->cipher)
 452                 fatal("%s: bad cipher name %s or pointer %p", __func__,
 453                     enc->name, enc->cipher);
 454
 455         /* Mac structure */
 456         mac->name = buffer_get_string(&b, NULL);
 457         if (mac->name == NULL || mac_init(mac, mac->name) == -1)
 458                 fatal("%s: can not init mac %s", __func__, mac->name);
 459         mac->enabled = buffer_get_int(&b);
 460         mac->key = buffer_get_string(&b, &len);
 461         if (len > mac->key_len)
 462                 fatal("%s: bad mac key length: %u > %d", __func__, len,
 463                     mac->key_len);
 464         mac->key_len = len;
 465
 466         /* Comp structure */
 467         comp->type = buffer_get_int(&b);
 468         comp->enabled = buffer_get_int(&b);
 469         comp->name = buffer_get_string(&b, NULL);
 470
 471         len = buffer_len(&b);
 472         if (len != 0)
 473                 error("newkeys_from_blob: remaining bytes in blob %u", len);
 474         buffer_free(&b);
 475         return (newkey);
 476 }
 477
 478 int
 479 mm_newkeys_to_blob(int mode, u_char **blobp, u_int *lenp)
 480 {
 481         Buffer b;
 482         int len;
 483         Enc *enc;
 484         Mac *mac;
 485         Comp *comp;
 486         Newkeys *newkey = newkeys[mode];
 487
 488         debug3("%s: converting %p", __func__, newkey);
 489
 490         if (newkey == NULL) {
 491                 error("%s: newkey == NULL", __func__);
 492                 return 0;
 493         }
 494         enc = &newkey->enc;
 495         mac = &newkey->mac;
 496         comp = &newkey->comp;
 497
 498         buffer_init(&b);
 499         /* Enc structure */
 500         buffer_put_cstring(&b, enc->name);
 501         /* The cipher struct is constant and shared, you export pointer */
 502         buffer_append(&b, &enc->cipher, sizeof(enc->cipher));
 503         buffer_put_int(&b, enc->enabled);
 504         buffer_put_int(&b, enc->block_size);
 505         buffer_put_string(&b, enc->key, enc->key_len);
 506         packet_get_keyiv(mode, enc->iv, enc->block_size);
 507         buffer_put_string(&b, enc->iv, enc->block_size);
 508
 509         /* Mac structure */
 510         buffer_put_cstring(&b, mac->name);
 511         buffer_put_int(&b, mac->enabled);
 512         buffer_put_string(&b, mac->key, mac->key_len);
 513
 514         /* Comp structure */
 515         buffer_put_int(&b, comp->type);
 516         buffer_put_int(&b, comp->enabled);
 517         buffer_put_cstring(&b, comp->name);
 518
 519         len = buffer_len(&b);
 520         if (lenp != NULL)
 521                 *lenp = len;
 522         if (blobp != NULL) {
 523                 *blobp = xmalloc(len);
 524                 memcpy(*blobp, buffer_ptr(&b), len);
 525         }
 526         memset(buffer_ptr(&b), 0, len);
 527         buffer_free(&b);
 528         return len;
 529 }
 530
 531 static void
 532 mm_send_kex(Buffer *m, Kex *kex)
 533 {
 534         buffer_put_string(m, kex->session_id, kex->session_id_len);
 535         buffer_put_int(m, kex->we_need);
 536         buffer_put_int(m, kex->hostkey_type);
 537         buffer_put_int(m, kex->kex_type);
 538         buffer_put_string(m, buffer_ptr(&kex->my), buffer_len(&kex->my));
 539         buffer_put_string(m, buffer_ptr(&kex->peer), buffer_len(&kex->peer));
 540         buffer_put_int(m, kex->flags);
 541         buffer_put_cstring(m, kex->client_version_string);
 542         buffer_put_cstring(m, kex->server_version_string);
 543 }
 544
 545 void
 546 mm_send_keystate(struct monitor *monitor)
 547 {
 548         Buffer m;
 549         u_char *blob, *p;
 550         u_int bloblen, plen;
 551         u_int32_t seqnr, packets;
 552         u_int64_t blocks;
 553
 554         buffer_init(&m);
 555
 556         if (!compat20) {
 557                 u_char iv[24];
 558                 u_char *key;
 559                 u_int ivlen, keylen;
 560
 561                 buffer_put_int(&m, packet_get_protocol_flags());
 562
 563                 buffer_put_int(&m, packet_get_ssh1_cipher());
 564
 565                 debug3("%s: Sending ssh1 KEY+IV", __func__);
 566                 keylen = packet_get_encryption_key(NULL);
 567                 key = xmalloc(keylen+1);        /* add 1 if keylen == 0 */
 568                 keylen = packet_get_encryption_key(key);
 569                 buffer_put_string(&m, key, keylen);
 570                 memset(key, 0, keylen);
 571                 xfree(key);
 572
 573                 ivlen = packet_get_keyiv_len(MODE_OUT);
 574                 packet_get_keyiv(MODE_OUT, iv, ivlen);
 575                 buffer_put_string(&m, iv, ivlen);
 576                 ivlen = packet_get_keyiv_len(MODE_OUT);
 577                 packet_get_keyiv(MODE_IN, iv, ivlen);
 578                 buffer_put_string(&m, iv, ivlen);
 579                 goto skip;
 580         } else {
 581                 /* Kex for rekeying */
 582                 mm_send_kex(&m, *monitor->m_pkex);
 583         }
 584
 585         debug3("%s: Sending new keys: %p %p",
 586             __func__, newkeys[MODE_OUT], newkeys[MODE_IN]);
 587
 588         /* Keys from Kex */
 589         if (!mm_newkeys_to_blob(MODE_OUT, &blob, &bloblen))
 590                 fatal("%s: conversion of newkeys failed", __func__);
 591
 592         buffer_put_string(&m, blob, bloblen);
 593         xfree(blob);
 594
 595         if (!mm_newkeys_to_blob(MODE_IN, &blob, &bloblen))
 596                 fatal("%s: conversion of newkeys failed", __func__);
 597
 598         buffer_put_string(&m, blob, bloblen);
 599         xfree(blob);
 600
 601         packet_get_state(MODE_OUT, &seqnr, &blocks, &packets);
 602         buffer_put_int(&m, seqnr);
 603         buffer_put_int64(&m, blocks);
 604         buffer_put_int(&m, packets);
 605         packet_get_state(MODE_IN, &seqnr, &blocks, &packets);
 606         buffer_put_int(&m, seqnr);
 607         buffer_put_int64(&m, blocks);
 608         buffer_put_int(&m, packets);
 609
 610         debug3("%s: New keys have been sent", __func__);
 611  skip:
 612         /* More key context */
 613         plen = packet_get_keycontext(MODE_OUT, NULL);
 614         p = xmalloc(plen+1);
 615         packet_get_keycontext(MODE_OUT, p);
 616         buffer_put_string(&m, p, plen);
 617         xfree(p);
 618
 619         plen = packet_get_keycontext(MODE_IN, NULL);
 620         p = xmalloc(plen+1);
 621         packet_get_keycontext(MODE_IN, p);
 622         buffer_put_string(&m, p, plen);
 623         xfree(p);
 624
 625         /* Compression state */
 626         debug3("%s: Sending compression state", __func__);
 627         buffer_put_string(&m, &outgoing_stream, sizeof(outgoing_stream));
 628         buffer_put_string(&m, &incoming_stream, sizeof(incoming_stream));
 629
 630         /* Network I/O buffers */
 631         buffer_put_string(&m, buffer_ptr(&input), buffer_len(&input));
 632         buffer_put_string(&m, buffer_ptr(&output), buffer_len(&output));
 633
 634         mm_request_send(monitor->m_recvfd, MONITOR_REQ_KEYEXPORT, &m);
 635         debug3("%s: Finished sending state", __func__);
 636
 637         buffer_free(&m);
 638 }
 639
 640 int
 641 mm_pty_allocate(int *ptyfd, int *ttyfd, char *namebuf, int namebuflen)
 642 {
 643         Buffer m;
 644         char *p, *msg;
 645         int success = 0;
 646
 647         buffer_init(&m);
 648         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTY, &m);
 649
 650         debug3("%s: waiting for MONITOR_ANS_PTY", __func__);
 651         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PTY, &m);
 652
 653         success = buffer_get_int(&m);
 654         if (success == 0) {
 655                 debug3("%s: pty alloc failed", __func__);
 656                 buffer_free(&m);
 657                 return (0);
 658         }
 659         p = buffer_get_string(&m, NULL);
 660         msg = buffer_get_string(&m, NULL);
 661         buffer_free(&m);
 662
 663         strlcpy(namebuf, p, namebuflen); /* Possible truncation */
 664         xfree(p);
 665
 666         buffer_append(&loginmsg, msg, strlen(msg));
 667         xfree(msg);
 668
 669         *ptyfd = mm_receive_fd(pmonitor->m_recvfd);
 670         *ttyfd = mm_receive_fd(pmonitor->m_recvfd);
 671
 672         /* Success */
 673         return (1);
 674 }
 675
 676 void
 677 mm_session_pty_cleanup2(Session *s)
 678 {
 679         Buffer m;
 680
 681         if (s->ttyfd == -1)
 682                 return;
 683         buffer_init(&m);
 684         buffer_put_cstring(&m, s->tty);
 685         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTYCLEANUP, &m);
 686         buffer_free(&m);
 687
 688         /* closed dup'ed master */
 689         if (close(s->ptymaster) < 0)
 690                 error("close(s->ptymaster): %s", strerror(errno));
 691
 692         /* unlink pty from session */
 693         s->ttyfd = -1;
 694 }
 695
 696 #ifdef USE_PAM
 697 void
 698 mm_start_pam(Authctxt *authctxt)
 699 {
 700         Buffer m;
 701
 702         debug3("%s entering", __func__);
 703         if (!options.use_pam)
 704                 fatal("UsePAM=no, but ended up in %s anyway", __func__);
 705
 706         buffer_init(&m);
 707         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_START, &m);
 708
 709         buffer_free(&m);
 710 }
 711
 712 u_int
 713 mm_do_pam_account(void)
 714 {
 715         Buffer m;
 716         u_int ret;
 717         char *msg;
 718
 719         debug3("%s entering", __func__);
 720         if (!options.use_pam)
 721                 fatal("UsePAM=no, but ended up in %s anyway", __func__);
 722
 723         buffer_init(&m);
 724         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_ACCOUNT, &m);
 725
 726         mm_request_receive_expect(pmonitor->m_recvfd,
 727             MONITOR_ANS_PAM_ACCOUNT, &m);
 728         ret = buffer_get_int(&m);
 729         msg = buffer_get_string(&m, NULL);
 730         buffer_append(&loginmsg, msg, strlen(msg));
 731         xfree(msg);
 732
 733         buffer_free(&m);
 734
 735         debug3("%s returning %d", __func__, ret);
 736
 737         return (ret);
 738 }
 739
 740 void *
 741 mm_sshpam_init_ctx(Authctxt *authctxt)
 742 {
 743         Buffer m;
 744         int success;
 745
 746         debug3("%s", __func__);
 747         buffer_init(&m);
 748         buffer_put_cstring(&m, authctxt->user);
 749         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_INIT_CTX, &m);
 750         debug3("%s: waiting for MONITOR_ANS_PAM_INIT_CTX", __func__);
 751         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_INIT_CTX, &m);
 752         success = buffer_get_int(&m);
 753         if (success == 0) {
 754                 debug3("%s: pam_init_ctx failed", __func__);
 755                 buffer_free(&m);
 756                 return (NULL);
 757         }
 758         buffer_free(&m);
 759         return (authctxt);
 760 }
 761
 762 int
 763 mm_sshpam_query(void *ctx, char **name, char **info,
 764     u_int *num, char ***prompts, u_int **echo_on)
 765 {
 766         Buffer m;
 767         int i, ret;
 768
 769         debug3("%s", __func__);
 770         buffer_init(&m);
 771         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_QUERY, &m);
 772         debug3("%s: waiting for MONITOR_ANS_PAM_QUERY", __func__);
 773         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_QUERY, &m);
 774         ret = buffer_get_int(&m);
 775         debug3("%s: pam_query returned %d", __func__, ret);
 776         *name = buffer_get_string(&m, NULL);
 777         *info = buffer_get_string(&m, NULL);
 778         *num = buffer_get_int(&m);
 779         *prompts = xmalloc((*num + 1) * sizeof(char *));
 780         *echo_on = xmalloc((*num + 1) * sizeof(u_int));
 781         for (i = 0; i < *num; ++i) {
 782                 (*prompts)[i] = buffer_get_string(&m, NULL);
 783                 (*echo_on)[i] = buffer_get_int(&m);
 784         }
 785         buffer_free(&m);
 786         return (ret);
 787 }
 788
 789 int
 790 mm_sshpam_respond(void *ctx, u_int num, char **resp)
 791 {
 792         Buffer m;
 793         int i, ret;
 794
 795         debug3("%s", __func__);
 796         buffer_init(&m);
 797         buffer_put_int(&m, num);
 798         for (i = 0; i < num; ++i)
 799                 buffer_put_cstring(&m, resp[i]);
 800         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_RESPOND, &m);
 801         debug3("%s: waiting for MONITOR_ANS_PAM_RESPOND", __func__);
 802         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_RESPOND, &m);
 803         ret = buffer_get_int(&m);
 804         debug3("%s: pam_respond returned %d", __func__, ret);
 805         buffer_free(&m);
 806         return (ret);
 807 }
 808
 809 void
 810 mm_sshpam_free_ctx(void *ctxtp)
 811 {
 812         Buffer m;
 813
 814         debug3("%s", __func__);
 815         buffer_init(&m);
 816         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_FREE_CTX, &m);
 817         debug3("%s: waiting for MONITOR_ANS_PAM_FREE_CTX", __func__);
 818         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_FREE_CTX, &m);
 819         buffer_free(&m);
 820 }
 821 #endif /* USE_PAM */
 822
 823 /* Request process termination */
 824
 825 void
 826 mm_terminate(void)
 827 {
 828         Buffer m;
 829
 830         buffer_init(&m);
 831         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_TERM, &m);
 832         buffer_free(&m);
 833 }
 834
 835 int
 836 mm_ssh1_session_key(BIGNUM *num)
 837 {
 838         int rsafail;
 839         Buffer m;
 840
 841         buffer_init(&m);
 842         buffer_put_bignum2(&m, num);
 843         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SESSKEY, &m);
 844
 845         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SESSKEY, &m);
 846
 847         rsafail = buffer_get_int(&m);
 848         buffer_get_bignum2(&m, num);
 849
 850         buffer_free(&m);
 851
 852         return (rsafail);
 853 }
 854
 855 static void
 856 mm_chall_setup(char **name, char **infotxt, u_int *numprompts,
 857     char ***prompts, u_int **echo_on)
 858 {
 859         *name = xstrdup("");
 860         *infotxt = xstrdup("");
 861         *numprompts = 1;
 862         *prompts = xmalloc(*numprompts * sizeof(char *));
 863         *echo_on = xmalloc(*numprompts * sizeof(u_int));
 864         (*echo_on)[0] = 0;
 865 }
 866
 867 int
 868 mm_bsdauth_query(void *ctx, char **name, char **infotxt,
 869    u_int *numprompts, char ***prompts, u_int **echo_on)
 870 {
 871         Buffer m;
 872         u_int success;
 873         char *challenge;
 874
 875         debug3("%s: entering", __func__);
 876
 877         buffer_init(&m);
 878         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHQUERY, &m);
 879
 880         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_BSDAUTHQUERY,
 881             &m);
 882         success = buffer_get_int(&m);
 883         if (success == 0) {
 884                 debug3("%s: no challenge", __func__);
 885                 buffer_free(&m);
 886                 return (-1);
 887         }
 888
 889         /* Get the challenge, and format the response */
 890         challenge  = buffer_get_string(&m, NULL);
 891         buffer_free(&m);
 892
 893         mm_chall_setup(name, infotxt, numprompts, prompts, echo_on);
 894         (*prompts)[0] = challenge;
 895
 896         debug3("%s: received challenge: %s", __func__, challenge);
 897
 898         return (0);
 899 }
 900
 901 int
 902 mm_bsdauth_respond(void *ctx, u_int numresponses, char **responses)
 903 {
 904         Buffer m;
 905         int authok;
 906
 907         debug3("%s: entering", __func__);
 908         if (numresponses != 1)
 909                 return (-1);
 910
 911         buffer_init(&m);
 912         buffer_put_cstring(&m, responses[0]);
 913         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHRESPOND, &m);
 914
 915         mm_request_receive_expect(pmonitor->m_recvfd,
 916             MONITOR_ANS_BSDAUTHRESPOND, &m);
 917
 918         authok = buffer_get_int(&m);
 919         buffer_free(&m);
 920
 921         return ((authok == 0) ? -1 : 0);
 922 }
 923
 924 #ifdef SKEY
 925 int
 926 mm_skey_query(void *ctx, char **name, char **infotxt,
 927    u_int *numprompts, char ***prompts, u_int **echo_on)
 928 {
 929         Buffer m;
 930         int len;
 931         u_int success;
 932         char *p, *challenge;
 933
 934         debug3("%s: entering", __func__);
 935
 936         buffer_init(&m);
 937         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SKEYQUERY, &m);
 938
 939         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SKEYQUERY,
 940             &m);
 941         success = buffer_get_int(&m);
 942         if (success == 0) {
 943                 debug3("%s: no challenge", __func__);
 944                 buffer_free(&m);
 945                 return (-1);
 946         }
 947
 948         /* Get the challenge, and format the response */
 949         challenge  = buffer_get_string(&m, NULL);
 950         buffer_free(&m);
 951
 952         debug3("%s: received challenge: %s", __func__, challenge);
 953
 954         mm_chall_setup(name, infotxt, numprompts, prompts, echo_on);
 955
 956         len = strlen(challenge) + strlen(SKEY_PROMPT) + 1;
 957         p = xmalloc(len);
 958         strlcpy(p, challenge, len);
 959         strlcat(p, SKEY_PROMPT, len);
 960         (*prompts)[0] = p;
 961         xfree(challenge);
 962
 963         return (0);
 964 }
 965
 966 int
 967 mm_skey_respond(void *ctx, u_int numresponses, char **responses)
 968 {
 969         Buffer m;
 970         int authok;
 971
 972         debug3("%s: entering", __func__);
 973         if (numresponses != 1)
 974                 return (-1);
 975
 976         buffer_init(&m);
 977         buffer_put_cstring(&m, responses[0]);
 978         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SKEYRESPOND, &m);
 979
 980         mm_request_receive_expect(pmonitor->m_recvfd,
 981             MONITOR_ANS_SKEYRESPOND, &m);
 982
 983         authok = buffer_get_int(&m);
 984         buffer_free(&m);
 985
 986         return ((authok == 0) ? -1 : 0);
 987 }
 988 #endif /* SKEY */
 989
 990 void
 991 mm_ssh1_session_id(u_char session_id[16])
 992 {
 993         Buffer m;
 994         int i;
 995
 996         debug3("%s entering", __func__);
 997
 998         buffer_init(&m);
 999         for (i = 0; i < 16; i++)
1000                 buffer_put_char(&m, session_id[i]);
1001
1002         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SESSID, &m);
1003         buffer_free(&m);
1004 }
1005
1006 int
1007 mm_auth_rsa_key_allowed(struct passwd *pw, BIGNUM *client_n, Key **rkey)
1008 {
1009         Buffer m;
1010         Key *key;
1011         u_char *blob;
1012         u_int blen;
1013         int allowed = 0, have_forced = 0;
1014
1015         debug3("%s entering", __func__);
1016
1017         buffer_init(&m);
1018         buffer_put_bignum2(&m, client_n);
1019
1020         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSAKEYALLOWED, &m);
1021         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSAKEYALLOWED, &m);
1022
1023         allowed = buffer_get_int(&m);
1024
1025         /* fake forced command */
1026         auth_clear_options();
1027         have_forced = buffer_get_int(&m);
1028         forced_command = have_forced ? xstrdup("true") : NULL;
1029
1030         if (allowed && rkey != NULL) {
1031                 blob = buffer_get_string(&m, &blen);
1032                 if ((key = key_from_blob(blob, blen)) == NULL)
1033                         fatal("%s: key_from_blob failed", __func__);
1034                 *rkey = key;
1035                 xfree(blob);
1036         }
1037         mm_send_debug(&m);
1038         buffer_free(&m);
1039
1040         return (allowed);
1041 }
1042
1043 BIGNUM *
1044 mm_auth_rsa_generate_challenge(Key *key)
1045 {
1046         Buffer m;
1047         BIGNUM *challenge;
1048         u_char *blob;
1049         u_int blen;
1050
1051         debug3("%s entering", __func__);
1052
1053         if ((challenge = BN_new()) == NULL)
1054                 fatal("%s: BN_new failed", __func__);
1055
1056         key->type = KEY_RSA;    /* XXX cheat for key_to_blob */
1057         if (key_to_blob(key, &blob, &blen) == 0)
1058                 fatal("%s: key_to_blob failed", __func__);
1059         key->type = KEY_RSA1;
1060
1061         buffer_init(&m);
1062         buffer_put_string(&m, blob, blen);
1063         xfree(blob);
1064
1065         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSACHALLENGE, &m);
1066         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSACHALLENGE, &m);
1067
1068         buffer_get_bignum2(&m, challenge);
1069         buffer_free(&m);
1070
1071         return (challenge);
1072 }
1073
1074 int
1075 mm_auth_rsa_verify_response(Key *key, BIGNUM *p, u_char response[16])
1076 {
1077         Buffer m;
1078         u_char *blob;
1079         u_int blen;
1080         int success = 0;
1081
1082         debug3("%s entering", __func__);
1083
1084         key->type = KEY_RSA;    /* XXX cheat for key_to_blob */
1085         if (key_to_blob(key, &blob, &blen) == 0)
1086                 fatal("%s: key_to_blob failed", __func__);
1087         key->type = KEY_RSA1;
1088
1089         buffer_init(&m);
1090         buffer_put_string(&m, blob, blen);
1091         buffer_put_string(&m, response, 16);
1092         xfree(blob);
1093
1094         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSARESPONSE, &m);
1095         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSARESPONSE, &m);
1096
1097         success = buffer_get_int(&m);
1098         buffer_free(&m);
1099
1100         return (success);
1101 }
1102
1103 #ifdef SSH_AUDIT_EVENTS
1104 void
1105 mm_audit_event(ssh_audit_event_t event)
1106 {
1107         Buffer m;
1108
1109         debug3("%s entering", __func__);
1110
1111         buffer_init(&m);
1112         buffer_put_int(&m, event);
1113
1114         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUDIT_EVENT, &m);
1115         buffer_free(&m);
1116 }
1117
1118 void
1119 mm_audit_run_command(const char *command)
1120 {
1121         Buffer m;
1122
1123         debug3("%s entering command %s", __func__, command);
1124
1125         buffer_init(&m);
1126         buffer_put_cstring(&m, command);
1127
1128         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUDIT_COMMAND, &m);
1129         buffer_free(&m);
1130 }
1131 #endif /* SSH_AUDIT_EVENTS */
1132
1133 #ifdef GSSAPI
1134 OM_uint32
1135 mm_ssh_gssapi_server_ctx(Gssctxt **ctx, gss_OID goid)
1136 {
1137         Buffer m;
1138         OM_uint32 major;
1139
1140         /* Client doesn't get to see the context */
1141         *ctx = NULL;
1142
1143         buffer_init(&m);
1144         buffer_put_string(&m, goid->elements, goid->length);
1145
1146         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSETUP, &m);
1147         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSETUP, &m);
1148
1149         major = buffer_get_int(&m);
1150
1151         buffer_free(&m);
1152         return (major);
1153 }
1154
1155 OM_uint32
1156 mm_ssh_gssapi_accept_ctx(Gssctxt *ctx, gss_buffer_desc *in,
1157     gss_buffer_desc *out, OM_uint32 *flags)
1158 {
1159         Buffer m;
1160         OM_uint32 major;
1161         u_int len;
1162
1163         buffer_init(&m);
1164         buffer_put_string(&m, in->value, in->length);
1165
1166         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSTEP, &m);
1167         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSTEP, &m);
1168
1169         major = buffer_get_int(&m);
1170         out->value = buffer_get_string(&m, &len);
1171         out->length = len;
1172         if (flags)
1173                 *flags = buffer_get_int(&m);
1174
1175         buffer_free(&m);
1176
1177         return (major);
1178 }
1179
1180 OM_uint32
1181 mm_ssh_gssapi_checkmic(Gssctxt *ctx, gss_buffer_t gssbuf, gss_buffer_t gssmic)
1182 {
1183         Buffer m;
1184         OM_uint32 major;
1185
1186         buffer_init(&m);
1187         buffer_put_string(&m, gssbuf->value, gssbuf->length);
1188         buffer_put_string(&m, gssmic->value, gssmic->length);
1189
1190         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSCHECKMIC, &m);
1191         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSCHECKMIC,
1192             &m);
1193
1194         major = buffer_get_int(&m);
1195         buffer_free(&m);
1196         return(major);
1197 }
1198
1199 int
1200 mm_ssh_gssapi_userok(char *user)
1201 {
1202         Buffer m;
1203         int authenticated = 0;
1204
1205         buffer_init(&m);
1206
1207         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSUSEROK, &m);
1208         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSUSEROK,
1209                                   &m);
1210
1211         authenticated = buffer_get_int(&m);
1212
1213         buffer_free(&m);
1214         debug3("%s: user %sauthenticated",__func__, authenticated ? "" : "not ");
1215         return (authenticated);
1216 }
1217 #endif /* GSSAPI */