crypto/openssh/monitor_wrap.c

   1 /* $OpenBSD: monitor_wrap.c,v 1.94 2017/10/02 19:33:20 djm Exp $ */
   2 /*
   3  * Copyright 2002 Niels Provos <provos@citi.umich.edu>
   4  * Copyright 2002 Markus Friedl <markus@openbsd.org>
   5  * All rights reserved.
   6  *
   7  * Redistribution and use in source and binary forms, with or without
   8  * modification, are permitted provided that the following conditions
   9  * are met:
  10  * 1. Redistributions of source code must retain the above copyright
  11  *    notice, this list of conditions and the following disclaimer.
  12  * 2. Redistributions in binary form must reproduce the above copyright
  13  *    notice, this list of conditions and the following disclaimer in the
  14  *    documentation and/or other materials provided with the distribution.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26  */
  27
  28 #include "includes.h"
  29
  30 #include <sys/types.h>
  31 #include <sys/uio.h>
  32
  33 #include <errno.h>
  34 #include <pwd.h>
  35 #include <signal.h>
  36 #include <stdarg.h>
  37 #include <stdio.h>
  38 #include <string.h>
  39 #include <unistd.h>
  40
  41 #ifdef WITH_OPENSSL
  42 #include <openssl/bn.h>
  43 #include <openssl/dh.h>
  44 #include <openssl/evp.h>
  45 #endif
  46
  47 #include "openbsd-compat/sys-queue.h"
  48 #include "xmalloc.h"
  49 #include "ssh.h"
  50 #ifdef WITH_OPENSSL
  51 #include "dh.h"
  52 #endif
  53 #include "buffer.h"
  54 #include "key.h"
  55 #include "cipher.h"
  56 #include "kex.h"
  57 #include "hostfile.h"
  58 #include "auth.h"
  59 #include "auth-options.h"
  60 #include "packet.h"
  61 #include "mac.h"
  62 #include "log.h"
  63 #include "auth-pam.h"
  64 #ifdef TARGET_OS_MAC    /* XXX Broken krb5 headers on Mac */
  65 #undef TARGET_OS_MAC
  66 #include "zlib.h"
  67 #define TARGET_OS_MAC 1
  68 #else
  69 #include "zlib.h"
  70 #endif
  71 #include "monitor.h"
  72 #ifdef GSSAPI
  73 #include "ssh-gss.h"
  74 #endif
  75 #include "monitor_wrap.h"
  76 #include "atomicio.h"
  77 #include "monitor_fdpass.h"
  78 #include "misc.h"
  79 #include "uuencode.h"
  80
  81 #include "channels.h"
  82 #include "session.h"
  83 #include "servconf.h"
  84
  85 #include "ssherr.h"
  86
  87 /* Imports */
  88 extern z_stream incoming_stream;
  89 extern z_stream outgoing_stream;
  90 extern struct monitor *pmonitor;
  91 extern Buffer loginmsg;
  92 extern ServerOptions options;
  93
  94 void
  95 mm_log_handler(LogLevel level, const char *msg, void *ctx)
  96 {
  97         Buffer log_msg;
  98         struct monitor *mon = (struct monitor *)ctx;
  99
 100         if (mon->m_log_sendfd == -1)
 101                 fatal("%s: no log channel", __func__);
 102
 103         buffer_init(&log_msg);
 104         /*
 105          * Placeholder for packet length. Will be filled in with the actual
 106          * packet length once the packet has been constucted. This saves
 107          * fragile math.
 108          */
 109         buffer_put_int(&log_msg, 0);
 110
 111         buffer_put_int(&log_msg, level);
 112         buffer_put_cstring(&log_msg, msg);
 113         put_u32(buffer_ptr(&log_msg), buffer_len(&log_msg) - 4);
 114         if (atomicio(vwrite, mon->m_log_sendfd, buffer_ptr(&log_msg),
 115             buffer_len(&log_msg)) != buffer_len(&log_msg))
 116                 fatal("%s: write: %s", __func__, strerror(errno));
 117         buffer_free(&log_msg);
 118 }
 119
 120 int
 121 mm_is_monitor(void)
 122 {
 123         /*
 124          * m_pid is only set in the privileged part, and
 125          * points to the unprivileged child.
 126          */
 127         return (pmonitor && pmonitor->m_pid > 0);
 128 }
 129
 130 void
 131 mm_request_send(int sock, enum monitor_reqtype type, Buffer *m)
 132 {
 133         u_int mlen = buffer_len(m);
 134         u_char buf[5];
 135
 136         debug3("%s entering: type %d", __func__, type);
 137
 138         put_u32(buf, mlen + 1);
 139         buf[4] = (u_char) type;         /* 1st byte of payload is mesg-type */
 140         if (atomicio(vwrite, sock, buf, sizeof(buf)) != sizeof(buf))
 141                 fatal("%s: write: %s", __func__, strerror(errno));
 142         if (atomicio(vwrite, sock, buffer_ptr(m), mlen) != mlen)
 143                 fatal("%s: write: %s", __func__, strerror(errno));
 144 }
 145
 146 void
 147 mm_request_receive(int sock, Buffer *m)
 148 {
 149         u_char buf[4];
 150         u_int msg_len;
 151
 152         debug3("%s entering", __func__);
 153
 154         if (atomicio(read, sock, buf, sizeof(buf)) != sizeof(buf)) {
 155                 if (errno == EPIPE)
 156                         cleanup_exit(255);
 157                 fatal("%s: read: %s", __func__, strerror(errno));
 158         }
 159         msg_len = get_u32(buf);
 160         if (msg_len > 256 * 1024)
 161                 fatal("%s: read: bad msg_len %d", __func__, msg_len);
 162         buffer_clear(m);
 163         buffer_append_space(m, msg_len);
 164         if (atomicio(read, sock, buffer_ptr(m), msg_len) != msg_len)
 165                 fatal("%s: read: %s", __func__, strerror(errno));
 166 }
 167
 168 void
 169 mm_request_receive_expect(int sock, enum monitor_reqtype type, Buffer *m)
 170 {
 171         u_char rtype;
 172
 173         debug3("%s entering: type %d", __func__, type);
 174
 175         mm_request_receive(sock, m);
 176         rtype = buffer_get_char(m);
 177         if (rtype != type)
 178                 fatal("%s: read: rtype %d != type %d", __func__,
 179                     rtype, type);
 180 }
 181
 182 #ifdef WITH_OPENSSL
 183 DH *
 184 mm_choose_dh(int min, int nbits, int max)
 185 {
 186         BIGNUM *p, *g;
 187         int success = 0;
 188         Buffer m;
 189
 190         buffer_init(&m);
 191         buffer_put_int(&m, min);
 192         buffer_put_int(&m, nbits);
 193         buffer_put_int(&m, max);
 194
 195         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_MODULI, &m);
 196
 197         debug3("%s: waiting for MONITOR_ANS_MODULI", __func__);
 198         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_MODULI, &m);
 199
 200         success = buffer_get_char(&m);
 201         if (success == 0)
 202                 fatal("%s: MONITOR_ANS_MODULI failed", __func__);
 203
 204         if ((p = BN_new()) == NULL)
 205                 fatal("%s: BN_new failed", __func__);
 206         if ((g = BN_new()) == NULL)
 207                 fatal("%s: BN_new failed", __func__);
 208         buffer_get_bignum2(&m, p);
 209         buffer_get_bignum2(&m, g);
 210
 211         debug3("%s: remaining %d", __func__, buffer_len(&m));
 212         buffer_free(&m);
 213
 214         return (dh_new_group(g, p));
 215 }
 216 #endif
 217
 218 int
 219 mm_key_sign(struct sshkey *key, u_char **sigp, u_int *lenp,
 220     const u_char *data, u_int datalen, const char *hostkey_alg)
 221 {
 222         struct kex *kex = *pmonitor->m_pkex;
 223         Buffer m;
 224
 225         debug3("%s entering", __func__);
 226
 227         buffer_init(&m);
 228         buffer_put_int(&m, kex->host_key_index(key, 0, active_state));
 229         buffer_put_string(&m, data, datalen);
 230         buffer_put_cstring(&m, hostkey_alg);
 231
 232         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SIGN, &m);
 233
 234         debug3("%s: waiting for MONITOR_ANS_SIGN", __func__);
 235         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SIGN, &m);
 236         *sigp  = buffer_get_string(&m, lenp);
 237         buffer_free(&m);
 238
 239         return (0);
 240 }
 241
 242 struct passwd *
 243 mm_getpwnamallow(const char *username)
 244 {
 245         struct ssh *ssh = active_state;         /* XXX */
 246         Buffer m;
 247         struct passwd *pw;
 248         u_int len, i;
 249         ServerOptions *newopts;
 250
 251         debug3("%s entering", __func__);
 252
 253         buffer_init(&m);
 254         buffer_put_cstring(&m, username);
 255
 256         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PWNAM, &m);
 257
 258         debug3("%s: waiting for MONITOR_ANS_PWNAM", __func__);
 259         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PWNAM, &m);
 260
 261         if (buffer_get_char(&m) == 0) {
 262                 pw = NULL;
 263                 goto out;
 264         }
 265         pw = buffer_get_string(&m, &len);
 266         if (len != sizeof(struct passwd))
 267                 fatal("%s: struct passwd size mismatch", __func__);
 268         pw->pw_name = buffer_get_string(&m, NULL);
 269         pw->pw_passwd = buffer_get_string(&m, NULL);
 270 #ifdef HAVE_STRUCT_PASSWD_PW_GECOS
 271         pw->pw_gecos = buffer_get_string(&m, NULL);
 272 #endif
 273 #ifdef HAVE_STRUCT_PASSWD_PW_CLASS
 274         pw->pw_class = buffer_get_string(&m, NULL);
 275 #endif
 276         pw->pw_dir = buffer_get_string(&m, NULL);
 277         pw->pw_shell = buffer_get_string(&m, NULL);
 278
 279 out:
 280         /* copy options block as a Match directive may have changed some */
 281         newopts = buffer_get_string(&m, &len);
 282         if (len != sizeof(*newopts))
 283                 fatal("%s: option block size mismatch", __func__);
 284
 285 #define M_CP_STROPT(x) do { \
 286                 if (newopts->x != NULL) \
 287                         newopts->x = buffer_get_string(&m, NULL); \
 288         } while (0)
 289 #define M_CP_STRARRAYOPT(x, nx) do { \
 290                 for (i = 0; i < newopts->nx; i++) \
 291                         newopts->x[i] = buffer_get_string(&m, NULL); \
 292         } while (0)
 293 #define M_CP_STRARRAYOPT_ALLOC(x, nx) do { \
 294                 newopts->x = newopts->nx == 0 ? \
 295                     NULL : xcalloc(newopts->nx, sizeof(*newopts->x)); \
 296                 M_CP_STRARRAYOPT(x, nx); \
 297         } while (0)
 298         /* See comment in servconf.h */
 299         COPY_MATCH_STRING_OPTS();
 300 #undef M_CP_STROPT
 301 #undef M_CP_STRARRAYOPT
 302 #undef M_CP_STRARRAYOPT_ALLOC
 303
 304         copy_set_server_options(&options, newopts, 1);
 305         log_change_level(options.log_level);
 306         process_permitopen(ssh, &options);
 307         free(newopts);
 308
 309         buffer_free(&m);
 310
 311         return (pw);
 312 }
 313
 314 char *
 315 mm_auth2_read_banner(void)
 316 {
 317         Buffer m;
 318         char *banner;
 319
 320         debug3("%s entering", __func__);
 321
 322         buffer_init(&m);
 323         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTH2_READ_BANNER, &m);
 324         buffer_clear(&m);
 325
 326         mm_request_receive_expect(pmonitor->m_recvfd,
 327             MONITOR_ANS_AUTH2_READ_BANNER, &m);
 328         banner = buffer_get_string(&m, NULL);
 329         buffer_free(&m);
 330
 331         /* treat empty banner as missing banner */
 332         if (strlen(banner) == 0) {
 333                 free(banner);
 334                 banner = NULL;
 335         }
 336         return (banner);
 337 }
 338
 339 /* Inform the privileged process about service and style */
 340
 341 void
 342 mm_inform_authserv(char *service, char *style)
 343 {
 344         Buffer m;
 345
 346         debug3("%s entering", __func__);
 347
 348         buffer_init(&m);
 349         buffer_put_cstring(&m, service);
 350         buffer_put_cstring(&m, style ? style : "");
 351
 352         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHSERV, &m);
 353
 354         buffer_free(&m);
 355 }
 356
 357 /* Do the password authentication */
 358 int
 359 mm_auth_password(Authctxt *authctxt, char *password)
 360 {
 361         Buffer m;
 362         int authenticated = 0;
 363
 364         debug3("%s entering", __func__);
 365
 366         buffer_init(&m);
 367         buffer_put_cstring(&m, password);
 368         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHPASSWORD, &m);
 369
 370         debug3("%s: waiting for MONITOR_ANS_AUTHPASSWORD", __func__);
 371         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_AUTHPASSWORD, &m);
 372
 373         authenticated = buffer_get_int(&m);
 374 #ifdef USE_PAM
 375         sshpam_set_maxtries_reached(buffer_get_int(&m));
 376 #endif
 377
 378         buffer_free(&m);
 379
 380         debug3("%s: user %sauthenticated",
 381             __func__, authenticated ? "" : "not ");
 382         return (authenticated);
 383 }
 384
 385 int
 386 mm_user_key_allowed(struct passwd *pw, struct sshkey *key,
 387     int pubkey_auth_attempt)
 388 {
 389         return (mm_key_allowed(MM_USERKEY, NULL, NULL, key,
 390             pubkey_auth_attempt));
 391 }
 392
 393 int
 394 mm_hostbased_key_allowed(struct passwd *pw, const char *user, const char *host,
 395     struct sshkey *key)
 396 {
 397         return (mm_key_allowed(MM_HOSTKEY, user, host, key, 0));
 398 }
 399
 400 int
 401 mm_key_allowed(enum mm_keytype type, const char *user, const char *host,
 402     struct sshkey *key, int pubkey_auth_attempt)
 403 {
 404         Buffer m;
 405         u_char *blob;
 406         u_int len;
 407         int allowed = 0, have_forced = 0;
 408
 409         debug3("%s entering", __func__);
 410
 411         /* Convert the key to a blob and the pass it over */
 412         if (!key_to_blob(key, &blob, &len))
 413                 return (0);
 414
 415         buffer_init(&m);
 416         buffer_put_int(&m, type);
 417         buffer_put_cstring(&m, user ? user : "");
 418         buffer_put_cstring(&m, host ? host : "");
 419         buffer_put_string(&m, blob, len);
 420         buffer_put_int(&m, pubkey_auth_attempt);
 421         free(blob);
 422
 423         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYALLOWED, &m);
 424
 425         debug3("%s: waiting for MONITOR_ANS_KEYALLOWED", __func__);
 426         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_KEYALLOWED, &m);
 427
 428         allowed = buffer_get_int(&m);
 429
 430         /* fake forced command */
 431         auth_clear_options();
 432         have_forced = buffer_get_int(&m);
 433         forced_command = have_forced ? xstrdup("true") : NULL;
 434
 435         buffer_free(&m);
 436
 437         return (allowed);
 438 }
 439
 440 /*
 441  * This key verify needs to send the key type along, because the
 442  * privileged parent makes the decision if the key is allowed
 443  * for authentication.
 444  */
 445
 446 int
 447 mm_sshkey_verify(const struct sshkey *key, const u_char *sig, size_t siglen,
 448     const u_char *data, size_t datalen, u_int compat)
 449 {
 450         Buffer m;
 451         u_char *blob;
 452         u_int len;
 453         u_int encoded_ret = 0;
 454
 455         debug3("%s entering", __func__);
 456
 457         /* Convert the key to a blob and the pass it over */
 458         if (!key_to_blob(key, &blob, &len))
 459                 return (0);
 460
 461         buffer_init(&m);
 462         buffer_put_string(&m, blob, len);
 463         buffer_put_string(&m, sig, siglen);
 464         buffer_put_string(&m, data, datalen);
 465         free(blob);
 466
 467         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYVERIFY, &m);
 468
 469         debug3("%s: waiting for MONITOR_ANS_KEYVERIFY", __func__);
 470         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_KEYVERIFY, &m);
 471
 472         encoded_ret = buffer_get_int(&m);
 473
 474         buffer_free(&m);
 475
 476         if (encoded_ret != 0)
 477                 return SSH_ERR_SIGNATURE_INVALID;
 478         return 0;
 479 }
 480
 481 void
 482 mm_send_keystate(struct monitor *monitor)
 483 {
 484         struct ssh *ssh = active_state;         /* XXX */
 485         struct sshbuf *m;
 486         int r;
 487
 488         if ((m = sshbuf_new()) == NULL)
 489                 fatal("%s: sshbuf_new failed", __func__);
 490         if ((r = ssh_packet_get_state(ssh, m)) != 0)
 491                 fatal("%s: get_state failed: %s",
 492                     __func__, ssh_err(r));
 493         mm_request_send(monitor->m_recvfd, MONITOR_REQ_KEYEXPORT, m);
 494         debug3("%s: Finished sending state", __func__);
 495         sshbuf_free(m);
 496 }
 497
 498 int
 499 mm_pty_allocate(int *ptyfd, int *ttyfd, char *namebuf, size_t namebuflen)
 500 {
 501         Buffer m;
 502         char *p, *msg;
 503         int success = 0, tmp1 = -1, tmp2 = -1;
 504
 505         /* Kludge: ensure there are fds free to receive the pty/tty */
 506         if ((tmp1 = dup(pmonitor->m_recvfd)) == -1 ||
 507             (tmp2 = dup(pmonitor->m_recvfd)) == -1) {
 508                 error("%s: cannot allocate fds for pty", __func__);
 509                 if (tmp1 > 0)
 510                         close(tmp1);
 511                 if (tmp2 > 0)
 512                         close(tmp2);
 513                 return 0;
 514         }
 515         close(tmp1);
 516         close(tmp2);
 517
 518         buffer_init(&m);
 519         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTY, &m);
 520
 521         debug3("%s: waiting for MONITOR_ANS_PTY", __func__);
 522         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PTY, &m);
 523
 524         success = buffer_get_int(&m);
 525         if (success == 0) {
 526                 debug3("%s: pty alloc failed", __func__);
 527                 buffer_free(&m);
 528                 return (0);
 529         }
 530         p = buffer_get_string(&m, NULL);
 531         msg = buffer_get_string(&m, NULL);
 532         buffer_free(&m);
 533
 534         strlcpy(namebuf, p, namebuflen); /* Possible truncation */
 535         free(p);
 536
 537         buffer_append(&loginmsg, msg, strlen(msg));
 538         free(msg);
 539
 540         if ((*ptyfd = mm_receive_fd(pmonitor->m_recvfd)) == -1 ||
 541             (*ttyfd = mm_receive_fd(pmonitor->m_recvfd)) == -1)
 542                 fatal("%s: receive fds failed", __func__);
 543
 544         /* Success */
 545         return (1);
 546 }
 547
 548 void
 549 mm_session_pty_cleanup2(Session *s)
 550 {
 551         Buffer m;
 552
 553         if (s->ttyfd == -1)
 554                 return;
 555         buffer_init(&m);
 556         buffer_put_cstring(&m, s->tty);
 557         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTYCLEANUP, &m);
 558         buffer_free(&m);
 559
 560         /* closed dup'ed master */
 561         if (s->ptymaster != -1 && close(s->ptymaster) < 0)
 562                 error("close(s->ptymaster/%d): %s",
 563                     s->ptymaster, strerror(errno));
 564
 565         /* unlink pty from session */
 566         s->ttyfd = -1;
 567 }
 568
 569 #ifdef USE_PAM
 570 void
 571 mm_start_pam(Authctxt *authctxt)
 572 {
 573         Buffer m;
 574
 575         debug3("%s entering", __func__);
 576         if (!options.use_pam)
 577                 fatal("UsePAM=no, but ended up in %s anyway", __func__);
 578
 579         buffer_init(&m);
 580         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_START, &m);
 581
 582         buffer_free(&m);
 583 }
 584
 585 u_int
 586 mm_do_pam_account(void)
 587 {
 588         Buffer m;
 589         u_int ret;
 590         char *msg;
 591
 592         debug3("%s entering", __func__);
 593         if (!options.use_pam)
 594                 fatal("UsePAM=no, but ended up in %s anyway", __func__);
 595
 596         buffer_init(&m);
 597         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_ACCOUNT, &m);
 598
 599         mm_request_receive_expect(pmonitor->m_recvfd,
 600             MONITOR_ANS_PAM_ACCOUNT, &m);
 601         ret = buffer_get_int(&m);
 602         msg = buffer_get_string(&m, NULL);
 603         buffer_append(&loginmsg, msg, strlen(msg));
 604         free(msg);
 605
 606         buffer_free(&m);
 607
 608         debug3("%s returning %d", __func__, ret);
 609
 610         return (ret);
 611 }
 612
 613 void *
 614 mm_sshpam_init_ctx(Authctxt *authctxt)
 615 {
 616         Buffer m;
 617         int success;
 618
 619         debug3("%s", __func__);
 620         buffer_init(&m);
 621         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_INIT_CTX, &m);
 622         debug3("%s: waiting for MONITOR_ANS_PAM_INIT_CTX", __func__);
 623         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_INIT_CTX, &m);
 624         success = buffer_get_int(&m);
 625         if (success == 0) {
 626                 debug3("%s: pam_init_ctx failed", __func__);
 627                 buffer_free(&m);
 628                 return (NULL);
 629         }
 630         buffer_free(&m);
 631         return (authctxt);
 632 }
 633
 634 int
 635 mm_sshpam_query(void *ctx, char **name, char **info,
 636     u_int *num, char ***prompts, u_int **echo_on)
 637 {
 638         Buffer m;
 639         u_int i;
 640         int ret;
 641
 642         debug3("%s", __func__);
 643         buffer_init(&m);
 644         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_QUERY, &m);
 645         debug3("%s: waiting for MONITOR_ANS_PAM_QUERY", __func__);
 646         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_QUERY, &m);
 647         ret = buffer_get_int(&m);
 648         debug3("%s: pam_query returned %d", __func__, ret);
 649         *name = buffer_get_string(&m, NULL);
 650         *info = buffer_get_string(&m, NULL);
 651         sshpam_set_maxtries_reached(buffer_get_int(&m));
 652         *num = buffer_get_int(&m);
 653         if (*num > PAM_MAX_NUM_MSG)
 654                 fatal("%s: recieved %u PAM messages, expected <= %u",
 655                     __func__, *num, PAM_MAX_NUM_MSG);
 656         *prompts = xcalloc((*num + 1), sizeof(char *));
 657         *echo_on = xcalloc((*num + 1), sizeof(u_int));
 658         for (i = 0; i < *num; ++i) {
 659                 (*prompts)[i] = buffer_get_string(&m, NULL);
 660                 (*echo_on)[i] = buffer_get_int(&m);
 661         }
 662         buffer_free(&m);
 663         return (ret);
 664 }
 665
 666 int
 667 mm_sshpam_respond(void *ctx, u_int num, char **resp)
 668 {
 669         Buffer m;
 670         u_int i;
 671         int ret;
 672
 673         debug3("%s", __func__);
 674         buffer_init(&m);
 675         buffer_put_int(&m, num);
 676         for (i = 0; i < num; ++i)
 677                 buffer_put_cstring(&m, resp[i]);
 678         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_RESPOND, &m);
 679         debug3("%s: waiting for MONITOR_ANS_PAM_RESPOND", __func__);
 680         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_RESPOND, &m);
 681         ret = buffer_get_int(&m);
 682         debug3("%s: pam_respond returned %d", __func__, ret);
 683         buffer_free(&m);
 684         return (ret);
 685 }
 686
 687 void
 688 mm_sshpam_free_ctx(void *ctxtp)
 689 {
 690         Buffer m;
 691
 692         debug3("%s", __func__);
 693         buffer_init(&m);
 694         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_FREE_CTX, &m);
 695         debug3("%s: waiting for MONITOR_ANS_PAM_FREE_CTX", __func__);
 696         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_FREE_CTX, &m);
 697         buffer_free(&m);
 698 }
 699 #endif /* USE_PAM */
 700
 701 /* Request process termination */
 702
 703 void
 704 mm_terminate(void)
 705 {
 706         Buffer m;
 707
 708         buffer_init(&m);
 709         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_TERM, &m);
 710         buffer_free(&m);
 711 }
 712
 713 static void
 714 mm_chall_setup(char **name, char **infotxt, u_int *numprompts,
 715     char ***prompts, u_int **echo_on)
 716 {
 717         *name = xstrdup("");
 718         *infotxt = xstrdup("");
 719         *numprompts = 1;
 720         *prompts = xcalloc(*numprompts, sizeof(char *));
 721         *echo_on = xcalloc(*numprompts, sizeof(u_int));
 722         (*echo_on)[0] = 0;
 723 }
 724
 725 int
 726 mm_bsdauth_query(void *ctx, char **name, char **infotxt,
 727    u_int *numprompts, char ***prompts, u_int **echo_on)
 728 {
 729         Buffer m;
 730         u_int success;
 731         char *challenge;
 732
 733         debug3("%s: entering", __func__);
 734
 735         buffer_init(&m);
 736         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHQUERY, &m);
 737
 738         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_BSDAUTHQUERY,
 739             &m);
 740         success = buffer_get_int(&m);
 741         if (success == 0) {
 742                 debug3("%s: no challenge", __func__);
 743                 buffer_free(&m);
 744                 return (-1);
 745         }
 746
 747         /* Get the challenge, and format the response */
 748         challenge  = buffer_get_string(&m, NULL);
 749         buffer_free(&m);
 750
 751         mm_chall_setup(name, infotxt, numprompts, prompts, echo_on);
 752         (*prompts)[0] = challenge;
 753
 754         debug3("%s: received challenge: %s", __func__, challenge);
 755
 756         return (0);
 757 }
 758
 759 int
 760 mm_bsdauth_respond(void *ctx, u_int numresponses, char **responses)
 761 {
 762         Buffer m;
 763         int authok;
 764
 765         debug3("%s: entering", __func__);
 766         if (numresponses != 1)
 767                 return (-1);
 768
 769         buffer_init(&m);
 770         buffer_put_cstring(&m, responses[0]);
 771         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHRESPOND, &m);
 772
 773         mm_request_receive_expect(pmonitor->m_recvfd,
 774             MONITOR_ANS_BSDAUTHRESPOND, &m);
 775
 776         authok = buffer_get_int(&m);
 777         buffer_free(&m);
 778
 779         return ((authok == 0) ? -1 : 0);
 780 }
 781
 782 #ifdef SKEY
 783 int
 784 mm_skey_query(void *ctx, char **name, char **infotxt,
 785    u_int *numprompts, char ***prompts, u_int **echo_on)
 786 {
 787         Buffer m;
 788         u_int success;
 789         char *challenge;
 790
 791         debug3("%s: entering", __func__);
 792
 793         buffer_init(&m);
 794         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SKEYQUERY, &m);
 795
 796         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SKEYQUERY,
 797             &m);
 798         success = buffer_get_int(&m);
 799         if (success == 0) {
 800                 debug3("%s: no challenge", __func__);
 801                 buffer_free(&m);
 802                 return (-1);
 803         }
 804
 805         /* Get the challenge, and format the response */
 806         challenge  = buffer_get_string(&m, NULL);
 807         buffer_free(&m);
 808
 809         debug3("%s: received challenge: %s", __func__, challenge);
 810
 811         mm_chall_setup(name, infotxt, numprompts, prompts, echo_on);
 812
 813         xasprintf(*prompts, "%s%s", challenge, SKEY_PROMPT);
 814         free(challenge);
 815
 816         return (0);
 817 }
 818
 819 int
 820 mm_skey_respond(void *ctx, u_int numresponses, char **responses)
 821 {
 822         Buffer m;
 823         int authok;
 824
 825         debug3("%s: entering", __func__);
 826         if (numresponses != 1)
 827                 return (-1);
 828
 829         buffer_init(&m);
 830         buffer_put_cstring(&m, responses[0]);
 831         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SKEYRESPOND, &m);
 832
 833         mm_request_receive_expect(pmonitor->m_recvfd,
 834             MONITOR_ANS_SKEYRESPOND, &m);
 835
 836         authok = buffer_get_int(&m);
 837         buffer_free(&m);
 838
 839         return ((authok == 0) ? -1 : 0);
 840 }
 841 #endif /* SKEY */
 842
 843 #ifdef SSH_AUDIT_EVENTS
 844 void
 845 mm_audit_event(ssh_audit_event_t event)
 846 {
 847         Buffer m;
 848
 849         debug3("%s entering", __func__);
 850
 851         buffer_init(&m);
 852         buffer_put_int(&m, event);
 853
 854         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUDIT_EVENT, &m);
 855         buffer_free(&m);
 856 }
 857
 858 void
 859 mm_audit_run_command(const char *command)
 860 {
 861         Buffer m;
 862
 863         debug3("%s entering command %s", __func__, command);
 864
 865         buffer_init(&m);
 866         buffer_put_cstring(&m, command);
 867
 868         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUDIT_COMMAND, &m);
 869         buffer_free(&m);
 870 }
 871 #endif /* SSH_AUDIT_EVENTS */
 872
 873 #ifdef GSSAPI
 874 OM_uint32
 875 mm_ssh_gssapi_server_ctx(Gssctxt **ctx, gss_OID goid)
 876 {
 877         Buffer m;
 878         OM_uint32 major;
 879
 880         /* Client doesn't get to see the context */
 881         *ctx = NULL;
 882
 883         buffer_init(&m);
 884         buffer_put_string(&m, goid->elements, goid->length);
 885
 886         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSETUP, &m);
 887         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSETUP, &m);
 888
 889         major = buffer_get_int(&m);
 890
 891         buffer_free(&m);
 892         return (major);
 893 }
 894
 895 OM_uint32
 896 mm_ssh_gssapi_accept_ctx(Gssctxt *ctx, gss_buffer_desc *in,
 897     gss_buffer_desc *out, OM_uint32 *flags)
 898 {
 899         Buffer m;
 900         OM_uint32 major;
 901         u_int len;
 902
 903         buffer_init(&m);
 904         buffer_put_string(&m, in->value, in->length);
 905
 906         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSTEP, &m);
 907         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSTEP, &m);
 908
 909         major = buffer_get_int(&m);
 910         out->value = buffer_get_string(&m, &len);
 911         out->length = len;
 912         if (flags)
 913                 *flags = buffer_get_int(&m);
 914
 915         buffer_free(&m);
 916
 917         return (major);
 918 }
 919
 920 OM_uint32
 921 mm_ssh_gssapi_checkmic(Gssctxt *ctx, gss_buffer_t gssbuf, gss_buffer_t gssmic)
 922 {
 923         Buffer m;
 924         OM_uint32 major;
 925
 926         buffer_init(&m);
 927         buffer_put_string(&m, gssbuf->value, gssbuf->length);
 928         buffer_put_string(&m, gssmic->value, gssmic->length);
 929
 930         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSCHECKMIC, &m);
 931         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSCHECKMIC,
 932             &m);
 933
 934         major = buffer_get_int(&m);
 935         buffer_free(&m);
 936         return(major);
 937 }
 938
 939 int
 940 mm_ssh_gssapi_userok(char *user)
 941 {
 942         Buffer m;
 943         int authenticated = 0;
 944
 945         buffer_init(&m);
 946
 947         mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSUSEROK, &m);
 948         mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSUSEROK,
 949                                   &m);
 950
 951         authenticated = buffer_get_int(&m);
 952
 953         buffer_free(&m);
 954         debug3("%s: user %sauthenticated",__func__, authenticated ? "" : "not ");
 955         return (authenticated);
 956 }
 957 #endif /* GSSAPI */
 958