crypto/openssh-4/monitor.c

   1 /* $OpenBSD: monitor.c,v 1.91 2007/05/17 20:52:13 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/param.h>
  32 #include <sys/socket.h>
  33 #include "openbsd-compat/sys-tree.h"
  34 #include <sys/wait.h>
  35
  36 #include <errno.h>
  37 #include <fcntl.h>
  38 #ifdef HAVE_PATHS_H
  39 #include <paths.h>
  40 #endif
  41 #include <pwd.h>
  42 #include <signal.h>
  43 #include <stdarg.h>
  44 #include <stdlib.h>
  45 #include <string.h>
  46 #include <unistd.h>
  47
  48 #ifdef SKEY
  49 #include <skey.h>
  50 #endif
  51
  52 #include <openssl/dh.h>
  53
  54 #include "xmalloc.h"
  55 #include "ssh.h"
  56 #include "key.h"
  57 #include "buffer.h"
  58 #include "hostfile.h"
  59 #include "auth.h"
  60 #include "cipher.h"
  61 #include "kex.h"
  62 #include "dh.h"
  63 #ifdef TARGET_OS_MAC    /* XXX Broken krb5 headers on Mac */
  64 #undef TARGET_OS_MAC
  65 #include "zlib.h"
  66 #define TARGET_OS_MAC 1
  67 #else
  68 #include "zlib.h"
  69 #endif
  70 #include "packet.h"
  71 #include "auth-options.h"
  72 #include "sshpty.h"
  73 #include "channels.h"
  74 #include "session.h"
  75 #include "sshlogin.h"
  76 #include "canohost.h"
  77 #include "log.h"
  78 #include "servconf.h"
  79 #include "monitor.h"
  80 #include "monitor_mm.h"
  81 #ifdef GSSAPI
  82 #include "ssh-gss.h"
  83 #endif
  84 #include "monitor_wrap.h"
  85 #include "monitor_fdpass.h"
  86 #include "misc.h"
  87 #include "compat.h"
  88 #include "ssh2.h"
  89
  90 #ifdef GSSAPI
  91 static Gssctxt *gsscontext = NULL;
  92 #endif
  93
  94 /* Imports */
  95 extern ServerOptions options;
  96 extern u_int utmp_len;
  97 extern Newkeys *current_keys[];
  98 extern z_stream incoming_stream;
  99 extern z_stream outgoing_stream;
 100 extern u_char session_id[];
 101 extern Buffer input, output;
 102 extern Buffer auth_debug;
 103 extern int auth_debug_init;
 104 extern Buffer loginmsg;
 105
 106 /* State exported from the child */
 107
 108 struct {
 109         z_stream incoming;
 110         z_stream outgoing;
 111         u_char *keyin;
 112         u_int keyinlen;
 113         u_char *keyout;
 114         u_int keyoutlen;
 115         u_char *ivin;
 116         u_int ivinlen;
 117         u_char *ivout;
 118         u_int ivoutlen;
 119         u_char *ssh1key;
 120         u_int ssh1keylen;
 121         int ssh1cipher;
 122         int ssh1protoflags;
 123         u_char *input;
 124         u_int ilen;
 125         u_char *output;
 126         u_int olen;
 127 } child_state;
 128
 129 /* Functions on the monitor that answer unprivileged requests */
 130
 131 int mm_answer_moduli(int, Buffer *);
 132 int mm_answer_sign(int, Buffer *);
 133 int mm_answer_pwnamallow(int, Buffer *);
 134 int mm_answer_auth2_read_banner(int, Buffer *);
 135 int mm_answer_authserv(int, Buffer *);
 136 int mm_answer_authpassword(int, Buffer *);
 137 int mm_answer_bsdauthquery(int, Buffer *);
 138 int mm_answer_bsdauthrespond(int, Buffer *);
 139 int mm_answer_skeyquery(int, Buffer *);
 140 int mm_answer_skeyrespond(int, Buffer *);
 141 int mm_answer_keyallowed(int, Buffer *);
 142 int mm_answer_keyverify(int, Buffer *);
 143 int mm_answer_pty(int, Buffer *);
 144 int mm_answer_pty_cleanup(int, Buffer *);
 145 int mm_answer_term(int, Buffer *);
 146 int mm_answer_rsa_keyallowed(int, Buffer *);
 147 int mm_answer_rsa_challenge(int, Buffer *);
 148 int mm_answer_rsa_response(int, Buffer *);
 149 int mm_answer_sesskey(int, Buffer *);
 150 int mm_answer_sessid(int, Buffer *);
 151
 152 #ifdef USE_PAM
 153 int mm_answer_pam_start(int, Buffer *);
 154 int mm_answer_pam_account(int, Buffer *);
 155 int mm_answer_pam_init_ctx(int, Buffer *);
 156 int mm_answer_pam_query(int, Buffer *);
 157 int mm_answer_pam_respond(int, Buffer *);
 158 int mm_answer_pam_free_ctx(int, Buffer *);
 159 #endif
 160
 161 #ifdef GSSAPI
 162 int mm_answer_gss_setup_ctx(int, Buffer *);
 163 int mm_answer_gss_accept_ctx(int, Buffer *);
 164 int mm_answer_gss_userok(int, Buffer *);
 165 int mm_answer_gss_checkmic(int, Buffer *);
 166 #endif
 167
 168 #ifdef SSH_AUDIT_EVENTS
 169 int mm_answer_audit_event(int, Buffer *);
 170 int mm_answer_audit_command(int, Buffer *);
 171 #endif
 172
 173 static Authctxt *authctxt;
 174 static BIGNUM *ssh1_challenge = NULL;   /* used for ssh1 rsa auth */
 175
 176 /* local state for key verify */
 177 static u_char *key_blob = NULL;
 178 static u_int key_bloblen = 0;
 179 static int key_blobtype = MM_NOKEY;
 180 static char *hostbased_cuser = NULL;
 181 static char *hostbased_chost = NULL;
 182 static char *auth_method = "unknown";
 183 static u_int session_id2_len = 0;
 184 static u_char *session_id2 = NULL;
 185 static pid_t monitor_child_pid;
 186
 187 struct mon_table {
 188         enum monitor_reqtype type;
 189         int flags;
 190         int (*f)(int, Buffer *);
 191 };
 192
 193 #define MON_ISAUTH      0x0004  /* Required for Authentication */
 194 #define MON_AUTHDECIDE  0x0008  /* Decides Authentication */
 195 #define MON_ONCE        0x0010  /* Disable after calling */
 196 #define MON_ALOG        0x0020  /* Log auth attempt without authenticating */
 197
 198 #define MON_AUTH        (MON_ISAUTH|MON_AUTHDECIDE)
 199
 200 #define MON_PERMIT      0x1000  /* Request is permitted */
 201
 202 struct mon_table mon_dispatch_proto20[] = {
 203     {MONITOR_REQ_MODULI, MON_ONCE, mm_answer_moduli},
 204     {MONITOR_REQ_SIGN, MON_ONCE, mm_answer_sign},
 205     {MONITOR_REQ_PWNAM, MON_ONCE, mm_answer_pwnamallow},
 206     {MONITOR_REQ_AUTHSERV, MON_ONCE, mm_answer_authserv},
 207     {MONITOR_REQ_AUTH2_READ_BANNER, MON_ONCE, mm_answer_auth2_read_banner},
 208     {MONITOR_REQ_AUTHPASSWORD, MON_AUTH, mm_answer_authpassword},
 209 #ifdef USE_PAM
 210     {MONITOR_REQ_PAM_START, MON_ONCE, mm_answer_pam_start},
 211     {MONITOR_REQ_PAM_ACCOUNT, 0, mm_answer_pam_account},
 212     {MONITOR_REQ_PAM_INIT_CTX, MON_ISAUTH, mm_answer_pam_init_ctx},
 213     {MONITOR_REQ_PAM_QUERY, MON_ISAUTH, mm_answer_pam_query},
 214     {MONITOR_REQ_PAM_RESPOND, MON_ISAUTH, mm_answer_pam_respond},
 215     {MONITOR_REQ_PAM_FREE_CTX, MON_ONCE|MON_AUTHDECIDE, mm_answer_pam_free_ctx},
 216 #endif
 217 #ifdef SSH_AUDIT_EVENTS
 218     {MONITOR_REQ_AUDIT_EVENT, MON_PERMIT, mm_answer_audit_event},
 219 #endif
 220 #ifdef BSD_AUTH
 221     {MONITOR_REQ_BSDAUTHQUERY, MON_ISAUTH, mm_answer_bsdauthquery},
 222     {MONITOR_REQ_BSDAUTHRESPOND, MON_AUTH, mm_answer_bsdauthrespond},
 223 #endif
 224 #ifdef SKEY
 225     {MONITOR_REQ_SKEYQUERY, MON_ISAUTH, mm_answer_skeyquery},
 226     {MONITOR_REQ_SKEYRESPOND, MON_AUTH, mm_answer_skeyrespond},
 227 #endif
 228     {MONITOR_REQ_KEYALLOWED, MON_ISAUTH, mm_answer_keyallowed},
 229     {MONITOR_REQ_KEYVERIFY, MON_AUTH, mm_answer_keyverify},
 230 #ifdef GSSAPI
 231     {MONITOR_REQ_GSSSETUP, MON_ISAUTH, mm_answer_gss_setup_ctx},
 232     {MONITOR_REQ_GSSSTEP, MON_ISAUTH, mm_answer_gss_accept_ctx},
 233     {MONITOR_REQ_GSSUSEROK, MON_AUTH, mm_answer_gss_userok},
 234     {MONITOR_REQ_GSSCHECKMIC, MON_ISAUTH, mm_answer_gss_checkmic},
 235 #endif
 236     {0, 0, NULL}
 237 };
 238
 239 struct mon_table mon_dispatch_postauth20[] = {
 240     {MONITOR_REQ_MODULI, 0, mm_answer_moduli},
 241     {MONITOR_REQ_SIGN, 0, mm_answer_sign},
 242     {MONITOR_REQ_PTY, 0, mm_answer_pty},
 243     {MONITOR_REQ_PTYCLEANUP, 0, mm_answer_pty_cleanup},
 244     {MONITOR_REQ_TERM, 0, mm_answer_term},
 245 #ifdef SSH_AUDIT_EVENTS
 246     {MONITOR_REQ_AUDIT_EVENT, MON_PERMIT, mm_answer_audit_event},
 247     {MONITOR_REQ_AUDIT_COMMAND, MON_PERMIT, mm_answer_audit_command},
 248 #endif
 249     {0, 0, NULL}
 250 };
 251
 252 struct mon_table mon_dispatch_proto15[] = {
 253     {MONITOR_REQ_PWNAM, MON_ONCE, mm_answer_pwnamallow},
 254     {MONITOR_REQ_SESSKEY, MON_ONCE, mm_answer_sesskey},
 255     {MONITOR_REQ_SESSID, MON_ONCE, mm_answer_sessid},
 256     {MONITOR_REQ_AUTHPASSWORD, MON_AUTH, mm_answer_authpassword},
 257     {MONITOR_REQ_RSAKEYALLOWED, MON_ISAUTH|MON_ALOG, mm_answer_rsa_keyallowed},
 258     {MONITOR_REQ_KEYALLOWED, MON_ISAUTH|MON_ALOG, mm_answer_keyallowed},
 259     {MONITOR_REQ_RSACHALLENGE, MON_ONCE, mm_answer_rsa_challenge},
 260     {MONITOR_REQ_RSARESPONSE, MON_ONCE|MON_AUTHDECIDE, mm_answer_rsa_response},
 261 #ifdef BSD_AUTH
 262     {MONITOR_REQ_BSDAUTHQUERY, MON_ISAUTH, mm_answer_bsdauthquery},
 263     {MONITOR_REQ_BSDAUTHRESPOND, MON_AUTH, mm_answer_bsdauthrespond},
 264 #endif
 265 #ifdef SKEY
 266     {MONITOR_REQ_SKEYQUERY, MON_ISAUTH, mm_answer_skeyquery},
 267     {MONITOR_REQ_SKEYRESPOND, MON_AUTH, mm_answer_skeyrespond},
 268 #endif
 269 #ifdef USE_PAM
 270     {MONITOR_REQ_PAM_START, MON_ONCE, mm_answer_pam_start},
 271     {MONITOR_REQ_PAM_ACCOUNT, 0, mm_answer_pam_account},
 272     {MONITOR_REQ_PAM_INIT_CTX, MON_ISAUTH, mm_answer_pam_init_ctx},
 273     {MONITOR_REQ_PAM_QUERY, MON_ISAUTH, mm_answer_pam_query},
 274     {MONITOR_REQ_PAM_RESPOND, MON_ISAUTH, mm_answer_pam_respond},
 275     {MONITOR_REQ_PAM_FREE_CTX, MON_ONCE|MON_AUTHDECIDE, mm_answer_pam_free_ctx},
 276 #endif
 277 #ifdef SSH_AUDIT_EVENTS
 278     {MONITOR_REQ_AUDIT_EVENT, MON_PERMIT, mm_answer_audit_event},
 279 #endif
 280     {0, 0, NULL}
 281 };
 282
 283 struct mon_table mon_dispatch_postauth15[] = {
 284     {MONITOR_REQ_PTY, MON_ONCE, mm_answer_pty},
 285     {MONITOR_REQ_PTYCLEANUP, MON_ONCE, mm_answer_pty_cleanup},
 286     {MONITOR_REQ_TERM, 0, mm_answer_term},
 287 #ifdef SSH_AUDIT_EVENTS
 288     {MONITOR_REQ_AUDIT_EVENT, MON_PERMIT, mm_answer_audit_event},
 289     {MONITOR_REQ_AUDIT_COMMAND, MON_PERMIT|MON_ONCE, mm_answer_audit_command},
 290 #endif
 291     {0, 0, NULL}
 292 };
 293
 294 struct mon_table *mon_dispatch;
 295
 296 /* Specifies if a certain message is allowed at the moment */
 297
 298 static void
 299 monitor_permit(struct mon_table *ent, enum monitor_reqtype type, int permit)
 300 {
 301         while (ent->f != NULL) {
 302                 if (ent->type == type) {
 303                         ent->flags &= ~MON_PERMIT;
 304                         ent->flags |= permit ? MON_PERMIT : 0;
 305                         return;
 306                 }
 307                 ent++;
 308         }
 309 }
 310
 311 static void
 312 monitor_permit_authentications(int permit)
 313 {
 314         struct mon_table *ent = mon_dispatch;
 315
 316         while (ent->f != NULL) {
 317                 if (ent->flags & MON_AUTH) {
 318                         ent->flags &= ~MON_PERMIT;
 319                         ent->flags |= permit ? MON_PERMIT : 0;
 320                 }
 321                 ent++;
 322         }
 323 }
 324
 325 void
 326 monitor_child_preauth(Authctxt *_authctxt, struct monitor *pmonitor)
 327 {
 328         struct mon_table *ent;
 329         int authenticated = 0;
 330
 331         debug3("preauth child monitor started");
 332
 333         authctxt = _authctxt;
 334         memset(authctxt, 0, sizeof(*authctxt));
 335
 336         authctxt->loginmsg = &loginmsg;
 337
 338         if (compat20) {
 339                 mon_dispatch = mon_dispatch_proto20;
 340
 341                 /* Permit requests for moduli and signatures */
 342                 monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
 343                 monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
 344         } else {
 345                 mon_dispatch = mon_dispatch_proto15;
 346
 347                 monitor_permit(mon_dispatch, MONITOR_REQ_SESSKEY, 1);
 348         }
 349
 350         /* The first few requests do not require asynchronous access */
 351         while (!authenticated) {
 352                 auth_method = "unknown";
 353                 authenticated = (monitor_read(pmonitor, mon_dispatch, &ent) == 1);
 354                 if (authenticated) {
 355                         if (!(ent->flags & MON_AUTHDECIDE))
 356                                 fatal("%s: unexpected authentication from %d",
 357                                     __func__, ent->type);
 358                         if (authctxt->pw->pw_uid == 0 &&
 359                             !auth_root_allowed(auth_method))
 360                                 authenticated = 0;
 361 #ifdef USE_PAM
 362                         /* PAM needs to perform account checks after auth */
 363                         if (options.use_pam && authenticated) {
 364                                 Buffer m;
 365
 366                                 buffer_init(&m);
 367                                 mm_request_receive_expect(pmonitor->m_sendfd,
 368                                     MONITOR_REQ_PAM_ACCOUNT, &m);
 369                                 authenticated = mm_answer_pam_account(pmonitor->m_sendfd, &m);
 370                                 buffer_free(&m);
 371                         }
 372 #endif
 373                 }
 374
 375                 if (ent->flags & (MON_AUTHDECIDE|MON_ALOG)) {
 376                         auth_log(authctxt, authenticated, auth_method,
 377                             compat20 ? " ssh2" : "");
 378                         if (!authenticated)
 379                                 authctxt->failures++;
 380                 }
 381         }
 382
 383         if (!authctxt->valid)
 384                 fatal("%s: authenticated invalid user", __func__);
 385         if (strcmp(auth_method, "unknown") == 0)
 386                 fatal("%s: authentication method name unknown", __func__);
 387
 388         debug("%s: %s has been authenticated by privileged process",
 389             __func__, authctxt->user);
 390
 391         mm_get_keystate(pmonitor);
 392 }
 393
 394 static void
 395 monitor_set_child_handler(pid_t pid)
 396 {
 397         monitor_child_pid = pid;
 398 }
 399
 400 static void
 401 monitor_child_handler(int sig)
 402 {
 403         kill(monitor_child_pid, sig);
 404 }
 405
 406 void
 407 monitor_child_postauth(struct monitor *pmonitor)
 408 {
 409         monitor_set_child_handler(pmonitor->m_pid);
 410         signal(SIGHUP, &monitor_child_handler);
 411         signal(SIGTERM, &monitor_child_handler);
 412         signal(SIGINT, &monitor_child_handler);
 413
 414         if (compat20) {
 415                 mon_dispatch = mon_dispatch_postauth20;
 416
 417                 /* Permit requests for moduli and signatures */
 418                 monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
 419                 monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
 420                 monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1);
 421         } else {
 422                 mon_dispatch = mon_dispatch_postauth15;
 423                 monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1);
 424         }
 425         if (!no_pty_flag) {
 426                 monitor_permit(mon_dispatch, MONITOR_REQ_PTY, 1);
 427                 monitor_permit(mon_dispatch, MONITOR_REQ_PTYCLEANUP, 1);
 428         }
 429
 430         for (;;)
 431                 monitor_read(pmonitor, mon_dispatch, NULL);
 432 }
 433
 434 void
 435 monitor_sync(struct monitor *pmonitor)
 436 {
 437         if (options.compression) {
 438                 /* The member allocation is not visible, so sync it */
 439                 mm_share_sync(&pmonitor->m_zlib, &pmonitor->m_zback);
 440         }
 441 }
 442
 443 int
 444 monitor_read(struct monitor *pmonitor, struct mon_table *ent,
 445     struct mon_table **pent)
 446 {
 447         Buffer m;
 448         int ret;
 449         u_char type;
 450
 451         buffer_init(&m);
 452
 453         mm_request_receive(pmonitor->m_sendfd, &m);
 454         type = buffer_get_char(&m);
 455
 456         debug3("%s: checking request %d", __func__, type);
 457
 458         while (ent->f != NULL) {
 459                 if (ent->type == type)
 460                         break;
 461                 ent++;
 462         }
 463
 464         if (ent->f != NULL) {
 465                 if (!(ent->flags & MON_PERMIT))
 466                         fatal("%s: unpermitted request %d", __func__,
 467                             type);
 468                 ret = (*ent->f)(pmonitor->m_sendfd, &m);
 469                 buffer_free(&m);
 470
 471                 /* The child may use this request only once, disable it */
 472                 if (ent->flags & MON_ONCE) {
 473                         debug2("%s: %d used once, disabling now", __func__,
 474                             type);
 475                         ent->flags &= ~MON_PERMIT;
 476                 }
 477
 478                 if (pent != NULL)
 479                         *pent = ent;
 480
 481                 return ret;
 482         }
 483
 484         fatal("%s: unsupported request: %d", __func__, type);
 485
 486         /* NOTREACHED */
 487         return (-1);
 488 }
 489
 490 /* allowed key state */
 491 static int
 492 monitor_allowed_key(u_char *blob, u_int bloblen)
 493 {
 494         /* make sure key is allowed */
 495         if (key_blob == NULL || key_bloblen != bloblen ||
 496             memcmp(key_blob, blob, key_bloblen))
 497                 return (0);
 498         return (1);
 499 }
 500
 501 static void
 502 monitor_reset_key_state(void)
 503 {
 504         /* reset state */
 505         if (key_blob != NULL)
 506                 xfree(key_blob);
 507         if (hostbased_cuser != NULL)
 508                 xfree(hostbased_cuser);
 509         if (hostbased_chost != NULL)
 510                 xfree(hostbased_chost);
 511         key_blob = NULL;
 512         key_bloblen = 0;
 513         key_blobtype = MM_NOKEY;
 514         hostbased_cuser = NULL;
 515         hostbased_chost = NULL;
 516 }
 517
 518 int
 519 mm_answer_moduli(int sock, Buffer *m)
 520 {
 521         DH *dh;
 522         int min, want, max;
 523
 524         min = buffer_get_int(m);
 525         want = buffer_get_int(m);
 526         max = buffer_get_int(m);
 527
 528         debug3("%s: got parameters: %d %d %d",
 529             __func__, min, want, max);
 530         /* We need to check here, too, in case the child got corrupted */
 531         if (max < min || want < min || max < want)
 532                 fatal("%s: bad parameters: %d %d %d",
 533                     __func__, min, want, max);
 534
 535         buffer_clear(m);
 536
 537         dh = choose_dh(min, want, max);
 538         if (dh == NULL) {
 539                 buffer_put_char(m, 0);
 540                 return (0);
 541         } else {
 542                 /* Send first bignum */
 543                 buffer_put_char(m, 1);
 544                 buffer_put_bignum2(m, dh->p);
 545                 buffer_put_bignum2(m, dh->g);
 546
 547                 DH_free(dh);
 548         }
 549         mm_request_send(sock, MONITOR_ANS_MODULI, m);
 550         return (0);
 551 }
 552
 553 int
 554 mm_answer_sign(int sock, Buffer *m)
 555 {
 556         Key *key;
 557         u_char *p;
 558         u_char *signature;
 559         u_int siglen, datlen;
 560         int keyid;
 561
 562         debug3("%s", __func__);
 563
 564         keyid = buffer_get_int(m);
 565         p = buffer_get_string(m, &datlen);
 566
 567         /*
 568          * Supported KEX types will only return SHA1 (20 byte) or
 569          * SHA256 (32 byte) hashes
 570          */
 571         if (datlen != 20 && datlen != 32)
 572                 fatal("%s: data length incorrect: %u", __func__, datlen);
 573
 574         /* save session id, it will be passed on the first call */
 575         if (session_id2_len == 0) {
 576                 session_id2_len = datlen;
 577                 session_id2 = xmalloc(session_id2_len);
 578                 memcpy(session_id2, p, session_id2_len);
 579         }
 580
 581         if ((key = get_hostkey_by_index(keyid)) == NULL)
 582                 fatal("%s: no hostkey from index %d", __func__, keyid);
 583         if (key_sign(key, &signature, &siglen, p, datlen) < 0)
 584                 fatal("%s: key_sign failed", __func__);
 585
 586         debug3("%s: signature %p(%u)", __func__, signature, siglen);
 587
 588         buffer_clear(m);
 589         buffer_put_string(m, signature, siglen);
 590
 591         xfree(p);
 592         xfree(signature);
 593
 594         mm_request_send(sock, MONITOR_ANS_SIGN, m);
 595
 596         /* Turn on permissions for getpwnam */
 597         monitor_permit(mon_dispatch, MONITOR_REQ_PWNAM, 1);
 598
 599         return (0);
 600 }
 601
 602 /* Retrieves the password entry and also checks if the user is permitted */
 603
 604 int
 605 mm_answer_pwnamallow(int sock, Buffer *m)
 606 {
 607         char *username;
 608         struct passwd *pwent;
 609         int allowed = 0;
 610
 611         debug3("%s", __func__);
 612
 613         if (authctxt->attempt++ != 0)
 614                 fatal("%s: multiple attempts for getpwnam", __func__);
 615
 616         username = buffer_get_string(m, NULL);
 617
 618         pwent = getpwnamallow(username);
 619
 620         authctxt->user = xstrdup(username);
 621         setproctitle("%s [priv]", pwent ? username : "unknown");
 622         xfree(username);
 623
 624         buffer_clear(m);
 625
 626         if (pwent == NULL) {
 627                 buffer_put_char(m, 0);
 628                 authctxt->pw = fakepw();
 629                 goto out;
 630         }
 631
 632         allowed = 1;
 633         authctxt->pw = pwent;
 634         authctxt->valid = 1;
 635
 636         buffer_put_char(m, 1);
 637         buffer_put_string(m, pwent, sizeof(struct passwd));
 638         buffer_put_cstring(m, pwent->pw_name);
 639         buffer_put_cstring(m, "*");
 640         buffer_put_cstring(m, pwent->pw_gecos);
 641 #ifdef HAVE_PW_CLASS_IN_PASSWD
 642         buffer_put_cstring(m, pwent->pw_class);
 643 #endif
 644         buffer_put_cstring(m, pwent->pw_dir);
 645         buffer_put_cstring(m, pwent->pw_shell);
 646         buffer_put_string(m, &options, sizeof(options));
 647         if (options.banner != NULL)
 648                 buffer_put_cstring(m, options.banner);
 649
 650  out:
 651         debug3("%s: sending MONITOR_ANS_PWNAM: %d", __func__, allowed);
 652         mm_request_send(sock, MONITOR_ANS_PWNAM, m);
 653
 654         /* For SSHv1 allow authentication now */
 655         if (!compat20)
 656                 monitor_permit_authentications(1);
 657         else {
 658                 /* Allow service/style information on the auth context */
 659                 monitor_permit(mon_dispatch, MONITOR_REQ_AUTHSERV, 1);
 660                 monitor_permit(mon_dispatch, MONITOR_REQ_AUTH2_READ_BANNER, 1);
 661         }
 662
 663 #ifdef USE_PAM
 664         if (options.use_pam)
 665                 monitor_permit(mon_dispatch, MONITOR_REQ_PAM_START, 1);
 666 #endif
 667
 668         return (0);
 669 }
 670
 671 int mm_answer_auth2_read_banner(int sock, Buffer *m)
 672 {
 673         char *banner;
 674
 675         buffer_clear(m);
 676         banner = auth2_read_banner();
 677         buffer_put_cstring(m, banner != NULL ? banner : "");
 678         mm_request_send(sock, MONITOR_ANS_AUTH2_READ_BANNER, m);
 679
 680         if (banner != NULL)
 681                 xfree(banner);
 682
 683         return (0);
 684 }
 685
 686 int
 687 mm_answer_authserv(int sock, Buffer *m)
 688 {
 689         monitor_permit_authentications(1);
 690
 691         authctxt->service = buffer_get_string(m, NULL);
 692         authctxt->style = buffer_get_string(m, NULL);
 693         debug3("%s: service=%s, style=%s",
 694             __func__, authctxt->service, authctxt->style);
 695
 696         if (strlen(authctxt->style) == 0) {
 697                 xfree(authctxt->style);
 698                 authctxt->style = NULL;
 699         }
 700
 701         return (0);
 702 }
 703
 704 int
 705 mm_answer_authpassword(int sock, Buffer *m)
 706 {
 707         static int call_count;
 708         char *passwd;
 709         int authenticated;
 710         u_int plen;
 711
 712         passwd = buffer_get_string(m, &plen);
 713         /* Only authenticate if the context is valid */
 714         authenticated = options.password_authentication &&
 715             auth_password(authctxt, passwd);
 716         memset(passwd, 0, strlen(passwd));
 717         xfree(passwd);
 718
 719         buffer_clear(m);
 720         buffer_put_int(m, authenticated);
 721
 722         debug3("%s: sending result %d", __func__, authenticated);
 723         mm_request_send(sock, MONITOR_ANS_AUTHPASSWORD, m);
 724
 725         call_count++;
 726         if (plen == 0 && call_count == 1)
 727                 auth_method = "none";
 728         else
 729                 auth_method = "password";
 730
 731         /* Causes monitor loop to terminate if authenticated */
 732         return (authenticated);
 733 }
 734
 735 #ifdef BSD_AUTH
 736 int
 737 mm_answer_bsdauthquery(int sock, Buffer *m)
 738 {
 739         char *name, *infotxt;
 740         u_int numprompts;
 741         u_int *echo_on;
 742         char **prompts;
 743         u_int success;
 744
 745         success = bsdauth_query(authctxt, &name, &infotxt, &numprompts,
 746             &prompts, &echo_on) < 0 ? 0 : 1;
 747
 748         buffer_clear(m);
 749         buffer_put_int(m, success);
 750         if (success)
 751                 buffer_put_cstring(m, prompts[0]);
 752
 753         debug3("%s: sending challenge success: %u", __func__, success);
 754         mm_request_send(sock, MONITOR_ANS_BSDAUTHQUERY, m);
 755
 756         if (success) {
 757                 xfree(name);
 758                 xfree(infotxt);
 759                 xfree(prompts);
 760                 xfree(echo_on);
 761         }
 762
 763         return (0);
 764 }
 765
 766 int
 767 mm_answer_bsdauthrespond(int sock, Buffer *m)
 768 {
 769         char *response;
 770         int authok;
 771
 772         if (authctxt->as == 0)
 773                 fatal("%s: no bsd auth session", __func__);
 774
 775         response = buffer_get_string(m, NULL);
 776         authok = options.challenge_response_authentication &&
 777             auth_userresponse(authctxt->as, response, 0);
 778         authctxt->as = NULL;
 779         debug3("%s: <%s> = <%d>", __func__, response, authok);
 780         xfree(response);
 781
 782         buffer_clear(m);
 783         buffer_put_int(m, authok);
 784
 785         debug3("%s: sending authenticated: %d", __func__, authok);
 786         mm_request_send(sock, MONITOR_ANS_BSDAUTHRESPOND, m);
 787
 788         auth_method = "bsdauth";
 789
 790         return (authok != 0);
 791 }
 792 #endif
 793
 794 #ifdef SKEY
 795 int
 796 mm_answer_skeyquery(int sock, Buffer *m)
 797 {
 798         struct skey skey;
 799         char challenge[1024];
 800         u_int success;
 801
 802         success = _compat_skeychallenge(&skey, authctxt->user, challenge,
 803             sizeof(challenge)) < 0 ? 0 : 1;
 804
 805         buffer_clear(m);
 806         buffer_put_int(m, success);
 807         if (success)
 808                 buffer_put_cstring(m, challenge);
 809
 810         debug3("%s: sending challenge success: %u", __func__, success);
 811         mm_request_send(sock, MONITOR_ANS_SKEYQUERY, m);
 812
 813         return (0);
 814 }
 815
 816 int
 817 mm_answer_skeyrespond(int sock, Buffer *m)
 818 {
 819         char *response;
 820         int authok;
 821
 822         response = buffer_get_string(m, NULL);
 823
 824         authok = (options.challenge_response_authentication &&
 825             authctxt->valid &&
 826             skey_haskey(authctxt->pw->pw_name) == 0 &&
 827             skey_passcheck(authctxt->pw->pw_name, response) != -1);
 828
 829         xfree(response);
 830
 831         buffer_clear(m);
 832         buffer_put_int(m, authok);
 833
 834         debug3("%s: sending authenticated: %d", __func__, authok);
 835         mm_request_send(sock, MONITOR_ANS_SKEYRESPOND, m);
 836
 837         auth_method = "skey";
 838
 839         return (authok != 0);
 840 }
 841 #endif
 842
 843 #ifdef USE_PAM
 844 int
 845 mm_answer_pam_start(int sock, Buffer *m)
 846 {
 847         if (!options.use_pam)
 848                 fatal("UsePAM not set, but ended up in %s anyway", __func__);
 849
 850         start_pam(authctxt);
 851
 852         monitor_permit(mon_dispatch, MONITOR_REQ_PAM_ACCOUNT, 1);
 853
 854         return (0);
 855 }
 856
 857 int
 858 mm_answer_pam_account(int sock, Buffer *m)
 859 {
 860         u_int ret;
 861
 862         if (!options.use_pam)
 863                 fatal("UsePAM not set, but ended up in %s anyway", __func__);
 864
 865         ret = do_pam_account();
 866
 867         buffer_put_int(m, ret);
 868         buffer_put_string(m, buffer_ptr(&loginmsg), buffer_len(&loginmsg));
 869
 870         mm_request_send(sock, MONITOR_ANS_PAM_ACCOUNT, m);
 871
 872         return (ret);
 873 }
 874
 875 static void *sshpam_ctxt, *sshpam_authok;
 876 extern KbdintDevice sshpam_device;
 877
 878 int
 879 mm_answer_pam_init_ctx(int sock, Buffer *m)
 880 {
 881
 882         debug3("%s", __func__);
 883         authctxt->user = buffer_get_string(m, NULL);
 884         sshpam_ctxt = (sshpam_device.init_ctx)(authctxt);
 885         sshpam_authok = NULL;
 886         buffer_clear(m);
 887         if (sshpam_ctxt != NULL) {
 888                 monitor_permit(mon_dispatch, MONITOR_REQ_PAM_FREE_CTX, 1);
 889                 buffer_put_int(m, 1);
 890         } else {
 891                 buffer_put_int(m, 0);
 892         }
 893         mm_request_send(sock, MONITOR_ANS_PAM_INIT_CTX, m);
 894         return (0);
 895 }
 896
 897 int
 898 mm_answer_pam_query(int sock, Buffer *m)
 899 {
 900         char *name, *info, **prompts;
 901         u_int i, num, *echo_on;
 902         int ret;
 903
 904         debug3("%s", __func__);
 905         sshpam_authok = NULL;
 906         ret = (sshpam_device.query)(sshpam_ctxt, &name, &info, &num, &prompts, &echo_on);
 907         if (ret == 0 && num == 0)
 908                 sshpam_authok = sshpam_ctxt;
 909         if (num > 1 || name == NULL || info == NULL)
 910                 ret = -1;
 911         buffer_clear(m);
 912         buffer_put_int(m, ret);
 913         buffer_put_cstring(m, name);
 914         xfree(name);
 915         buffer_put_cstring(m, info);
 916         xfree(info);
 917         buffer_put_int(m, num);
 918         for (i = 0; i < num; ++i) {
 919                 buffer_put_cstring(m, prompts[i]);
 920                 xfree(prompts[i]);
 921                 buffer_put_int(m, echo_on[i]);
 922         }
 923         if (prompts != NULL)
 924                 xfree(prompts);
 925         if (echo_on != NULL)
 926                 xfree(echo_on);
 927         auth_method = "keyboard-interactive/pam";
 928         mm_request_send(sock, MONITOR_ANS_PAM_QUERY, m);
 929         return (0);
 930 }
 931
 932 int
 933 mm_answer_pam_respond(int sock, Buffer *m)
 934 {
 935         char **resp;
 936         u_int i, num;
 937         int ret;
 938
 939         debug3("%s", __func__);
 940         sshpam_authok = NULL;
 941         num = buffer_get_int(m);
 942         if (num > 0) {
 943                 resp = xcalloc(num, sizeof(char *));
 944                 for (i = 0; i < num; ++i)
 945                         resp[i] = buffer_get_string(m, NULL);
 946                 ret = (sshpam_device.respond)(sshpam_ctxt, num, resp);
 947                 for (i = 0; i < num; ++i)
 948                         xfree(resp[i]);
 949                 xfree(resp);
 950         } else {
 951                 ret = (sshpam_device.respond)(sshpam_ctxt, num, NULL);
 952         }
 953         buffer_clear(m);
 954         buffer_put_int(m, ret);
 955         mm_request_send(sock, MONITOR_ANS_PAM_RESPOND, m);
 956         auth_method = "keyboard-interactive/pam";
 957         if (ret == 0)
 958                 sshpam_authok = sshpam_ctxt;
 959         return (0);
 960 }
 961
 962 int
 963 mm_answer_pam_free_ctx(int sock, Buffer *m)
 964 {
 965
 966         debug3("%s", __func__);
 967         (sshpam_device.free_ctx)(sshpam_ctxt);
 968         buffer_clear(m);
 969         mm_request_send(sock, MONITOR_ANS_PAM_FREE_CTX, m);
 970         auth_method = "keyboard-interactive/pam";
 971         return (sshpam_authok == sshpam_ctxt);
 972 }
 973 #endif
 974
 975 static void
 976 mm_append_debug(Buffer *m)
 977 {
 978         if (auth_debug_init && buffer_len(&auth_debug)) {
 979                 debug3("%s: Appending debug messages for child", __func__);
 980                 buffer_append(m, buffer_ptr(&auth_debug),
 981                     buffer_len(&auth_debug));
 982                 buffer_clear(&auth_debug);
 983         }
 984 }
 985
 986 int
 987 mm_answer_keyallowed(int sock, Buffer *m)
 988 {
 989         Key *key;
 990         char *cuser, *chost;
 991         u_char *blob;
 992         u_int bloblen;
 993         enum mm_keytype type = 0;
 994         int allowed = 0;
 995
 996         debug3("%s entering", __func__);
 997
 998         type = buffer_get_int(m);
 999         cuser = buffer_get_string(m, NULL);
1000         chost = buffer_get_string(m, NULL);
1001         blob = buffer_get_string(m, &bloblen);
1002
1003         key = key_from_blob(blob, bloblen);
1004
1005         if ((compat20 && type == MM_RSAHOSTKEY) ||
1006             (!compat20 && type != MM_RSAHOSTKEY))
1007                 fatal("%s: key type and protocol mismatch", __func__);
1008
1009         debug3("%s: key_from_blob: %p", __func__, key);
1010
1011         if (key != NULL && authctxt->valid) {
1012                 switch (type) {
1013                 case MM_USERKEY:
1014                         allowed = options.pubkey_authentication &&
1015                             user_key_allowed(authctxt->pw, key);
1016                         auth_method = "publickey";
1017                         break;
1018                 case MM_HOSTKEY:
1019                         allowed = options.hostbased_authentication &&
1020                             hostbased_key_allowed(authctxt->pw,
1021                             cuser, chost, key);
1022                         auth_method = "hostbased";
1023                         break;
1024                 case MM_RSAHOSTKEY:
1025                         key->type = KEY_RSA1; /* XXX */
1026                         allowed = options.rhosts_rsa_authentication &&
1027                             auth_rhosts_rsa_key_allowed(authctxt->pw,
1028                             cuser, chost, key);
1029                         auth_method = "rsa";
1030                         break;
1031                 default:
1032                         fatal("%s: unknown key type %d", __func__, type);
1033                         break;
1034                 }
1035         }
1036         if (key != NULL)
1037                 key_free(key);
1038
1039         /* clear temporarily storage (used by verify) */
1040         monitor_reset_key_state();
1041
1042         if (allowed) {
1043                 /* Save temporarily for comparison in verify */
1044                 key_blob = blob;
1045                 key_bloblen = bloblen;
1046                 key_blobtype = type;
1047                 hostbased_cuser = cuser;
1048                 hostbased_chost = chost;
1049         } else {
1050                 /* Log failed attempt */
1051                 auth_log(authctxt, 0, auth_method, compat20 ? " ssh2" : "");
1052                 xfree(blob);
1053                 xfree(cuser);
1054                 xfree(chost);
1055         }
1056
1057         debug3("%s: key %p is %s",
1058             __func__, key, allowed ? "allowed" : "disallowed");
1059
1060         buffer_clear(m);
1061         buffer_put_int(m, allowed);
1062         buffer_put_int(m, forced_command != NULL);
1063
1064         mm_append_debug(m);
1065
1066         mm_request_send(sock, MONITOR_ANS_KEYALLOWED, m);
1067
1068         if (type == MM_RSAHOSTKEY)
1069                 monitor_permit(mon_dispatch, MONITOR_REQ_RSACHALLENGE, allowed);
1070
1071         return (0);
1072 }
1073
1074 static int
1075 monitor_valid_userblob(u_char *data, u_int datalen)
1076 {
1077         Buffer b;
1078         char *p;
1079         u_int len;
1080         int fail = 0;
1081
1082         buffer_init(&b);
1083         buffer_append(&b, data, datalen);
1084
1085         if (datafellows & SSH_OLD_SESSIONID) {
1086                 p = buffer_ptr(&b);
1087                 len = buffer_len(&b);
1088                 if ((session_id2 == NULL) ||
1089                     (len < session_id2_len) ||
1090                     (memcmp(p, session_id2, session_id2_len) != 0))
1091                         fail++;
1092                 buffer_consume(&b, session_id2_len);
1093         } else {
1094                 p = buffer_get_string(&b, &len);
1095                 if ((session_id2 == NULL) ||
1096                     (len != session_id2_len) ||
1097                     (memcmp(p, session_id2, session_id2_len) != 0))
1098                         fail++;
1099                 xfree(p);
1100         }
1101         if (buffer_get_char(&b) != SSH2_MSG_USERAUTH_REQUEST)
1102                 fail++;
1103         p = buffer_get_string(&b, NULL);
1104         if (strcmp(authctxt->user, p) != 0) {
1105                 logit("wrong user name passed to monitor: expected %s != %.100s",
1106                     authctxt->user, p);
1107                 fail++;
1108         }
1109         xfree(p);
1110         buffer_skip_string(&b);
1111         if (datafellows & SSH_BUG_PKAUTH) {
1112                 if (!buffer_get_char(&b))
1113                         fail++;
1114         } else {
1115                 p = buffer_get_string(&b, NULL);
1116                 if (strcmp("publickey", p) != 0)
1117                         fail++;
1118                 xfree(p);
1119                 if (!buffer_get_char(&b))
1120                         fail++;
1121                 buffer_skip_string(&b);
1122         }
1123         buffer_skip_string(&b);
1124         if (buffer_len(&b) != 0)
1125                 fail++;
1126         buffer_free(&b);
1127         return (fail == 0);
1128 }
1129
1130 static int
1131 monitor_valid_hostbasedblob(u_char *data, u_int datalen, char *cuser,
1132     char *chost)
1133 {
1134         Buffer b;
1135         char *p;
1136         u_int len;
1137         int fail = 0;
1138
1139         buffer_init(&b);
1140         buffer_append(&b, data, datalen);
1141
1142         p = buffer_get_string(&b, &len);
1143         if ((session_id2 == NULL) ||
1144             (len != session_id2_len) ||
1145             (memcmp(p, session_id2, session_id2_len) != 0))
1146                 fail++;
1147         xfree(p);
1148
1149         if (buffer_get_char(&b) != SSH2_MSG_USERAUTH_REQUEST)
1150                 fail++;
1151         p = buffer_get_string(&b, NULL);
1152         if (strcmp(authctxt->user, p) != 0) {
1153                 logit("wrong user name passed to monitor: expected %s != %.100s",
1154                     authctxt->user, p);
1155                 fail++;
1156         }
1157         xfree(p);
1158         buffer_skip_string(&b); /* service */
1159         p = buffer_get_string(&b, NULL);
1160         if (strcmp(p, "hostbased") != 0)
1161                 fail++;
1162         xfree(p);
1163         buffer_skip_string(&b); /* pkalg */
1164         buffer_skip_string(&b); /* pkblob */
1165
1166         /* verify client host, strip trailing dot if necessary */
1167         p = buffer_get_string(&b, NULL);
1168         if (((len = strlen(p)) > 0) && p[len - 1] == '.')
1169                 p[len - 1] = '\0';
1170         if (strcmp(p, chost) != 0)
1171                 fail++;
1172         xfree(p);
1173
1174         /* verify client user */
1175         p = buffer_get_string(&b, NULL);
1176         if (strcmp(p, cuser) != 0)
1177                 fail++;
1178         xfree(p);
1179
1180         if (buffer_len(&b) != 0)
1181                 fail++;
1182         buffer_free(&b);
1183         return (fail == 0);
1184 }
1185
1186 int
1187 mm_answer_keyverify(int sock, Buffer *m)
1188 {
1189         Key *key;
1190         u_char *signature, *data, *blob;
1191         u_int signaturelen, datalen, bloblen;
1192         int verified = 0;
1193         int valid_data = 0;
1194
1195         blob = buffer_get_string(m, &bloblen);
1196         signature = buffer_get_string(m, &signaturelen);
1197         data = buffer_get_string(m, &datalen);
1198
1199         if (hostbased_cuser == NULL || hostbased_chost == NULL ||
1200           !monitor_allowed_key(blob, bloblen))
1201                 fatal("%s: bad key, not previously allowed", __func__);
1202
1203         key = key_from_blob(blob, bloblen);
1204         if (key == NULL)
1205                 fatal("%s: bad public key blob", __func__);
1206
1207         switch (key_blobtype) {
1208         case MM_USERKEY:
1209                 valid_data = monitor_valid_userblob(data, datalen);
1210                 break;
1211         case MM_HOSTKEY:
1212                 valid_data = monitor_valid_hostbasedblob(data, datalen,
1213                     hostbased_cuser, hostbased_chost);
1214                 break;
1215         default:
1216                 valid_data = 0;
1217                 break;
1218         }
1219         if (!valid_data)
1220                 fatal("%s: bad signature data blob", __func__);
1221
1222         verified = key_verify(key, signature, signaturelen, data, datalen);
1223         debug3("%s: key %p signature %s",
1224             __func__, key, (verified == 1) ? "verified" : "unverified");
1225
1226         key_free(key);
1227         xfree(blob);
1228         xfree(signature);
1229         xfree(data);
1230
1231         auth_method = key_blobtype == MM_USERKEY ? "publickey" : "hostbased";
1232
1233         monitor_reset_key_state();
1234
1235         buffer_clear(m);
1236         buffer_put_int(m, verified);
1237         mm_request_send(sock, MONITOR_ANS_KEYVERIFY, m);
1238
1239         return (verified == 1);
1240 }
1241
1242 static void
1243 mm_record_login(Session *s, struct passwd *pw)
1244 {
1245         socklen_t fromlen;
1246         struct sockaddr_storage from;
1247
1248         /*
1249          * Get IP address of client. If the connection is not a socket, let
1250          * the address be 0.0.0.0.
1251          */
1252         memset(&from, 0, sizeof(from));
1253         fromlen = sizeof(from);
1254         if (packet_connection_is_on_socket()) {
1255                 if (getpeername(packet_get_connection_in(),
1256                     (struct sockaddr *)&from, &fromlen) < 0) {
1257                         debug("getpeername: %.100s", strerror(errno));
1258                         cleanup_exit(255);
1259                 }
1260         }
1261         /* Record that there was a login on that tty from the remote host. */
1262         record_login(s->pid, s->tty, pw->pw_name, pw->pw_uid,
1263             get_remote_name_or_ip(utmp_len, options.use_dns),
1264             (struct sockaddr *)&from, fromlen);
1265 }
1266
1267 static void
1268 mm_session_close(Session *s)
1269 {
1270         debug3("%s: session %d pid %ld", __func__, s->self, (long)s->pid);
1271         if (s->ttyfd != -1) {
1272                 debug3("%s: tty %s ptyfd %d", __func__, s->tty, s->ptyfd);
1273                 session_pty_cleanup2(s);
1274         }
1275         s->used = 0;
1276 }
1277
1278 int
1279 mm_answer_pty(int sock, Buffer *m)
1280 {
1281         extern struct monitor *pmonitor;
1282         Session *s;
1283         int res, fd0;
1284
1285         debug3("%s entering", __func__);
1286
1287         buffer_clear(m);
1288         s = session_new();
1289         if (s == NULL)
1290                 goto error;
1291         s->authctxt = authctxt;
1292         s->pw = authctxt->pw;
1293         s->pid = pmonitor->m_pid;
1294         res = pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty));
1295         if (res == 0)
1296                 goto error;
1297         pty_setowner(authctxt->pw, s->tty);
1298
1299         buffer_put_int(m, 1);
1300         buffer_put_cstring(m, s->tty);
1301
1302         /* We need to trick ttyslot */
1303         if (dup2(s->ttyfd, 0) == -1)
1304                 fatal("%s: dup2", __func__);
1305
1306         mm_record_login(s, authctxt->pw);
1307
1308         /* Now we can close the file descriptor again */
1309         close(0);
1310
1311         /* send messages generated by record_login */
1312         buffer_put_string(m, buffer_ptr(&loginmsg), buffer_len(&loginmsg));
1313         buffer_clear(&loginmsg);
1314
1315         mm_request_send(sock, MONITOR_ANS_PTY, m);
1316
1317         mm_send_fd(sock, s->ptyfd);
1318         mm_send_fd(sock, s->ttyfd);
1319
1320         /* make sure nothing uses fd 0 */
1321         if ((fd0 = open(_PATH_DEVNULL, O_RDONLY)) < 0)
1322                 fatal("%s: open(/dev/null): %s", __func__, strerror(errno));
1323         if (fd0 != 0)
1324                 error("%s: fd0 %d != 0", __func__, fd0);
1325
1326         /* slave is not needed */
1327         close(s->ttyfd);
1328         s->ttyfd = s->ptyfd;
1329         /* no need to dup() because nobody closes ptyfd */
1330         s->ptymaster = s->ptyfd;
1331
1332         debug3("%s: tty %s ptyfd %d", __func__, s->tty, s->ttyfd);
1333
1334         return (0);
1335
1336  error:
1337         if (s != NULL)
1338                 mm_session_close(s);
1339         buffer_put_int(m, 0);
1340         mm_request_send(sock, MONITOR_ANS_PTY, m);
1341         return (0);
1342 }
1343
1344 int
1345 mm_answer_pty_cleanup(int sock, Buffer *m)
1346 {
1347         Session *s;
1348         char *tty;
1349
1350         debug3("%s entering", __func__);
1351
1352         tty = buffer_get_string(m, NULL);
1353         if ((s = session_by_tty(tty)) != NULL)
1354                 mm_session_close(s);
1355         buffer_clear(m);
1356         xfree(tty);
1357         return (0);
1358 }
1359
1360 int
1361 mm_answer_sesskey(int sock, Buffer *m)
1362 {
1363         BIGNUM *p;
1364         int rsafail;
1365
1366         /* Turn off permissions */
1367         monitor_permit(mon_dispatch, MONITOR_REQ_SESSKEY, 0);
1368
1369         if ((p = BN_new()) == NULL)
1370                 fatal("%s: BN_new", __func__);
1371
1372         buffer_get_bignum2(m, p);
1373
1374         rsafail = ssh1_session_key(p);
1375
1376         buffer_clear(m);
1377         buffer_put_int(m, rsafail);
1378         buffer_put_bignum2(m, p);
1379
1380         BN_clear_free(p);
1381
1382         mm_request_send(sock, MONITOR_ANS_SESSKEY, m);
1383
1384         /* Turn on permissions for sessid passing */
1385         monitor_permit(mon_dispatch, MONITOR_REQ_SESSID, 1);
1386
1387         return (0);
1388 }
1389
1390 int
1391 mm_answer_sessid(int sock, Buffer *m)
1392 {
1393         int i;
1394
1395         debug3("%s entering", __func__);
1396
1397         if (buffer_len(m) != 16)
1398                 fatal("%s: bad ssh1 session id", __func__);
1399         for (i = 0; i < 16; i++)
1400                 session_id[i] = buffer_get_char(m);
1401
1402         /* Turn on permissions for getpwnam */
1403         monitor_permit(mon_dispatch, MONITOR_REQ_PWNAM, 1);
1404
1405         return (0);
1406 }
1407
1408 int
1409 mm_answer_rsa_keyallowed(int sock, Buffer *m)
1410 {
1411         BIGNUM *client_n;
1412         Key *key = NULL;
1413         u_char *blob = NULL;
1414         u_int blen = 0;
1415         int allowed = 0;
1416
1417         debug3("%s entering", __func__);
1418
1419         auth_method = "rsa";
1420         if (options.rsa_authentication && authctxt->valid) {
1421                 if ((client_n = BN_new()) == NULL)
1422                         fatal("%s: BN_new", __func__);
1423                 buffer_get_bignum2(m, client_n);
1424                 allowed = auth_rsa_key_allowed(authctxt->pw, client_n, &key);
1425                 BN_clear_free(client_n);
1426         }
1427         buffer_clear(m);
1428         buffer_put_int(m, allowed);
1429         buffer_put_int(m, forced_command != NULL);
1430
1431         /* clear temporarily storage (used by generate challenge) */
1432         monitor_reset_key_state();
1433
1434         if (allowed && key != NULL) {
1435                 key->type = KEY_RSA;    /* cheat for key_to_blob */
1436                 if (key_to_blob(key, &blob, &blen) == 0)
1437                         fatal("%s: key_to_blob failed", __func__);
1438                 buffer_put_string(m, blob, blen);
1439
1440                 /* Save temporarily for comparison in verify */
1441                 key_blob = blob;
1442                 key_bloblen = blen;
1443                 key_blobtype = MM_RSAUSERKEY;
1444         }
1445         if (key != NULL)
1446                 key_free(key);
1447
1448         mm_append_debug(m);
1449
1450         mm_request_send(sock, MONITOR_ANS_RSAKEYALLOWED, m);
1451
1452         monitor_permit(mon_dispatch, MONITOR_REQ_RSACHALLENGE, allowed);
1453         monitor_permit(mon_dispatch, MONITOR_REQ_RSARESPONSE, 0);
1454         return (0);
1455 }
1456
1457 int
1458 mm_answer_rsa_challenge(int sock, Buffer *m)
1459 {
1460         Key *key = NULL;
1461         u_char *blob;
1462         u_int blen;
1463
1464         debug3("%s entering", __func__);
1465
1466         if (!authctxt->valid)
1467                 fatal("%s: authctxt not valid", __func__);
1468         blob = buffer_get_string(m, &blen);
1469         if (!monitor_allowed_key(blob, blen))
1470                 fatal("%s: bad key, not previously allowed", __func__);
1471         if (key_blobtype != MM_RSAUSERKEY && key_blobtype != MM_RSAHOSTKEY)
1472                 fatal("%s: key type mismatch", __func__);
1473         if ((key = key_from_blob(blob, blen)) == NULL)
1474                 fatal("%s: received bad key", __func__);
1475
1476         if (ssh1_challenge)
1477                 BN_clear_free(ssh1_challenge);
1478         ssh1_challenge = auth_rsa_generate_challenge(key);
1479
1480         buffer_clear(m);
1481         buffer_put_bignum2(m, ssh1_challenge);
1482
1483         debug3("%s sending reply", __func__);
1484         mm_request_send(sock, MONITOR_ANS_RSACHALLENGE, m);
1485
1486         monitor_permit(mon_dispatch, MONITOR_REQ_RSARESPONSE, 1);
1487
1488         xfree(blob);
1489         key_free(key);
1490         return (0);
1491 }
1492
1493 int
1494 mm_answer_rsa_response(int sock, Buffer *m)
1495 {
1496         Key *key = NULL;
1497         u_char *blob, *response;
1498         u_int blen, len;
1499         int success;
1500
1501         debug3("%s entering", __func__);
1502
1503         if (!authctxt->valid)
1504                 fatal("%s: authctxt not valid", __func__);
1505         if (ssh1_challenge == NULL)
1506                 fatal("%s: no ssh1_challenge", __func__);
1507
1508         blob = buffer_get_string(m, &blen);
1509         if (!monitor_allowed_key(blob, blen))
1510                 fatal("%s: bad key, not previously allowed", __func__);
1511         if (key_blobtype != MM_RSAUSERKEY && key_blobtype != MM_RSAHOSTKEY)
1512                 fatal("%s: key type mismatch: %d", __func__, key_blobtype);
1513         if ((key = key_from_blob(blob, blen)) == NULL)
1514                 fatal("%s: received bad key", __func__);
1515         response = buffer_get_string(m, &len);
1516         if (len != 16)
1517                 fatal("%s: received bad response to challenge", __func__);
1518         success = auth_rsa_verify_response(key, ssh1_challenge, response);
1519
1520         xfree(blob);
1521         key_free(key);
1522         xfree(response);
1523
1524         auth_method = key_blobtype == MM_RSAUSERKEY ? "rsa" : "rhosts-rsa";
1525
1526         /* reset state */
1527         BN_clear_free(ssh1_challenge);
1528         ssh1_challenge = NULL;
1529         monitor_reset_key_state();
1530
1531         buffer_clear(m);
1532         buffer_put_int(m, success);
1533         mm_request_send(sock, MONITOR_ANS_RSARESPONSE, m);
1534
1535         return (success);
1536 }
1537
1538 int
1539 mm_answer_term(int sock, Buffer *req)
1540 {
1541         extern struct monitor *pmonitor;
1542         int res, status;
1543
1544         debug3("%s: tearing down sessions", __func__);
1545
1546         /* The child is terminating */
1547         session_destroy_all(&mm_session_close);
1548
1549         while (waitpid(pmonitor->m_pid, &status, 0) == -1)
1550                 if (errno != EINTR)
1551                         exit(1);
1552
1553         res = WIFEXITED(status) ? WEXITSTATUS(status) : 1;
1554
1555         /* Terminate process */
1556         exit(res);
1557 }
1558
1559 #ifdef SSH_AUDIT_EVENTS
1560 /* Report that an audit event occurred */
1561 int
1562 mm_answer_audit_event(int socket, Buffer *m)
1563 {
1564         ssh_audit_event_t event;
1565
1566         debug3("%s entering", __func__);
1567
1568         event = buffer_get_int(m);
1569         switch(event) {
1570         case SSH_AUTH_FAIL_PUBKEY:
1571         case SSH_AUTH_FAIL_HOSTBASED:
1572         case SSH_AUTH_FAIL_GSSAPI:
1573         case SSH_LOGIN_EXCEED_MAXTRIES:
1574         case SSH_LOGIN_ROOT_DENIED:
1575         case SSH_CONNECTION_CLOSE:
1576         case SSH_INVALID_USER:
1577                 audit_event(event);
1578                 break;
1579         default:
1580                 fatal("Audit event type %d not permitted", event);
1581         }
1582
1583         return (0);
1584 }
1585
1586 int
1587 mm_answer_audit_command(int socket, Buffer *m)
1588 {
1589         u_int len;
1590         char *cmd;
1591
1592         debug3("%s entering", __func__);
1593         cmd = buffer_get_string(m, &len);
1594         /* sanity check command, if so how? */
1595         audit_run_command(cmd);
1596         xfree(cmd);
1597         return (0);
1598 }
1599 #endif /* SSH_AUDIT_EVENTS */
1600
1601 void
1602 monitor_apply_keystate(struct monitor *pmonitor)
1603 {
1604         if (compat20) {
1605                 set_newkeys(MODE_IN);
1606                 set_newkeys(MODE_OUT);
1607         } else {
1608                 packet_set_protocol_flags(child_state.ssh1protoflags);
1609                 packet_set_encryption_key(child_state.ssh1key,
1610                     child_state.ssh1keylen, child_state.ssh1cipher);
1611                 xfree(child_state.ssh1key);
1612         }
1613
1614         /* for rc4 and other stateful ciphers */
1615         packet_set_keycontext(MODE_OUT, child_state.keyout);
1616         xfree(child_state.keyout);
1617         packet_set_keycontext(MODE_IN, child_state.keyin);
1618         xfree(child_state.keyin);
1619
1620         if (!compat20) {
1621                 packet_set_iv(MODE_OUT, child_state.ivout);
1622                 xfree(child_state.ivout);
1623                 packet_set_iv(MODE_IN, child_state.ivin);
1624                 xfree(child_state.ivin);
1625         }
1626
1627         memcpy(&incoming_stream, &child_state.incoming,
1628             sizeof(incoming_stream));
1629         memcpy(&outgoing_stream, &child_state.outgoing,
1630             sizeof(outgoing_stream));
1631
1632         /* Update with new address */
1633         if (options.compression)
1634                 mm_init_compression(pmonitor->m_zlib);
1635
1636         /* Network I/O buffers */
1637         /* XXX inefficient for large buffers, need: buffer_init_from_string */
1638         buffer_clear(&input);
1639         buffer_append(&input, child_state.input, child_state.ilen);
1640         memset(child_state.input, 0, child_state.ilen);
1641         xfree(child_state.input);
1642
1643         buffer_clear(&output);
1644         buffer_append(&output, child_state.output, child_state.olen);
1645         memset(child_state.output, 0, child_state.olen);
1646         xfree(child_state.output);
1647 }
1648
1649 static Kex *
1650 mm_get_kex(Buffer *m)
1651 {
1652         Kex *kex;
1653         void *blob;
1654         u_int bloblen;
1655
1656         kex = xcalloc(1, sizeof(*kex));
1657         kex->session_id = buffer_get_string(m, &kex->session_id_len);
1658         if ((session_id2 == NULL) ||
1659             (kex->session_id_len != session_id2_len) ||
1660             (memcmp(kex->session_id, session_id2, session_id2_len) != 0))
1661                 fatal("mm_get_get: internal error: bad session id");
1662         kex->we_need = buffer_get_int(m);
1663         kex->kex[KEX_DH_GRP1_SHA1] = kexdh_server;
1664         kex->kex[KEX_DH_GRP14_SHA1] = kexdh_server;
1665         kex->kex[KEX_DH_GEX_SHA1] = kexgex_server;
1666         kex->kex[KEX_DH_GEX_SHA256] = kexgex_server;
1667         kex->server = 1;
1668         kex->hostkey_type = buffer_get_int(m);
1669         kex->kex_type = buffer_get_int(m);
1670         blob = buffer_get_string(m, &bloblen);
1671         buffer_init(&kex->my);
1672         buffer_append(&kex->my, blob, bloblen);
1673         xfree(blob);
1674         blob = buffer_get_string(m, &bloblen);
1675         buffer_init(&kex->peer);
1676         buffer_append(&kex->peer, blob, bloblen);
1677         xfree(blob);
1678         kex->done = 1;
1679         kex->flags = buffer_get_int(m);
1680         kex->client_version_string = buffer_get_string(m, NULL);
1681         kex->server_version_string = buffer_get_string(m, NULL);
1682         kex->load_host_key=&get_hostkey_by_type;
1683         kex->host_key_index=&get_hostkey_index;
1684
1685         return (kex);
1686 }
1687
1688 /* This function requries careful sanity checking */
1689
1690 void
1691 mm_get_keystate(struct monitor *pmonitor)
1692 {
1693         Buffer m;
1694         u_char *blob, *p;
1695         u_int bloblen, plen;
1696         u_int32_t seqnr, packets;
1697         u_int64_t blocks;
1698
1699         debug3("%s: Waiting for new keys", __func__);
1700
1701         buffer_init(&m);
1702         mm_request_receive_expect(pmonitor->m_sendfd, MONITOR_REQ_KEYEXPORT, &m);
1703         if (!compat20) {
1704                 child_state.ssh1protoflags = buffer_get_int(&m);
1705                 child_state.ssh1cipher = buffer_get_int(&m);
1706                 child_state.ssh1key = buffer_get_string(&m,
1707                     &child_state.ssh1keylen);
1708                 child_state.ivout = buffer_get_string(&m,
1709                     &child_state.ivoutlen);
1710                 child_state.ivin = buffer_get_string(&m, &child_state.ivinlen);
1711                 goto skip;
1712         } else {
1713                 /* Get the Kex for rekeying */
1714                 *pmonitor->m_pkex = mm_get_kex(&m);
1715         }
1716
1717         blob = buffer_get_string(&m, &bloblen);
1718         current_keys[MODE_OUT] = mm_newkeys_from_blob(blob, bloblen);
1719         xfree(blob);
1720
1721         debug3("%s: Waiting for second key", __func__);
1722         blob = buffer_get_string(&m, &bloblen);
1723         current_keys[MODE_IN] = mm_newkeys_from_blob(blob, bloblen);
1724         xfree(blob);
1725
1726         /* Now get sequence numbers for the packets */
1727         seqnr = buffer_get_int(&m);
1728         blocks = buffer_get_int64(&m);
1729         packets = buffer_get_int(&m);
1730         packet_set_state(MODE_OUT, seqnr, blocks, packets);
1731         seqnr = buffer_get_int(&m);
1732         blocks = buffer_get_int64(&m);
1733         packets = buffer_get_int(&m);
1734         packet_set_state(MODE_IN, seqnr, blocks, packets);
1735
1736  skip:
1737         /* Get the key context */
1738         child_state.keyout = buffer_get_string(&m, &child_state.keyoutlen);
1739         child_state.keyin  = buffer_get_string(&m, &child_state.keyinlen);
1740
1741         debug3("%s: Getting compression state", __func__);
1742         /* Get compression state */
1743         p = buffer_get_string(&m, &plen);
1744         if (plen != sizeof(child_state.outgoing))
1745                 fatal("%s: bad request size", __func__);
1746         memcpy(&child_state.outgoing, p, sizeof(child_state.outgoing));
1747         xfree(p);
1748
1749         p = buffer_get_string(&m, &plen);
1750         if (plen != sizeof(child_state.incoming))
1751                 fatal("%s: bad request size", __func__);
1752         memcpy(&child_state.incoming, p, sizeof(child_state.incoming));
1753         xfree(p);
1754
1755         /* Network I/O buffers */
1756         debug3("%s: Getting Network I/O buffers", __func__);
1757         child_state.input = buffer_get_string(&m, &child_state.ilen);
1758         child_state.output = buffer_get_string(&m, &child_state.olen);
1759
1760         buffer_free(&m);
1761 }
1762
1763
1764 /* Allocation functions for zlib */
1765 void *
1766 mm_zalloc(struct mm_master *mm, u_int ncount, u_int size)
1767 {
1768         size_t len = (size_t) size * ncount;
1769         void *address;
1770
1771         if (len == 0 || ncount > SIZE_T_MAX / size)
1772                 fatal("%s: mm_zalloc(%u, %u)", __func__, ncount, size);
1773
1774         address = mm_malloc(mm, len);
1775
1776         return (address);
1777 }
1778
1779 void
1780 mm_zfree(struct mm_master *mm, void *address)
1781 {
1782         mm_free(mm, address);
1783 }
1784
1785 void
1786 mm_init_compression(struct mm_master *mm)
1787 {
1788         outgoing_stream.zalloc = (alloc_func)mm_zalloc;
1789         outgoing_stream.zfree = (free_func)mm_zfree;
1790         outgoing_stream.opaque = mm;
1791
1792         incoming_stream.zalloc = (alloc_func)mm_zalloc;
1793         incoming_stream.zfree = (free_func)mm_zfree;
1794         incoming_stream.opaque = mm;
1795 }
1796
1797 /* XXX */
1798
1799 #define FD_CLOSEONEXEC(x) do { \
1800         if (fcntl(x, F_SETFD, 1) == -1) \
1801                 fatal("fcntl(%d, F_SETFD)", x); \
1802 } while (0)
1803
1804 static void
1805 monitor_socketpair(int *pair)
1806 {
1807 #ifdef HAVE_SOCKETPAIR
1808         if (socketpair(AF_UNIX, SOCK_STREAM, 0, pair) == -1)
1809                 fatal("%s: socketpair", __func__);
1810 #else
1811         fatal("%s: UsePrivilegeSeparation=yes not supported",
1812             __func__);
1813 #endif
1814         FD_CLOSEONEXEC(pair[0]);
1815         FD_CLOSEONEXEC(pair[1]);
1816 }
1817
1818 #define MM_MEMSIZE      65536
1819
1820 struct monitor *
1821 monitor_init(void)
1822 {
1823         struct monitor *mon;
1824         int pair[2];
1825
1826         mon = xcalloc(1, sizeof(*mon));
1827
1828         monitor_socketpair(pair);
1829
1830         mon->m_recvfd = pair[0];
1831         mon->m_sendfd = pair[1];
1832
1833         /* Used to share zlib space across processes */
1834         if (options.compression) {
1835                 mon->m_zback = mm_create(NULL, MM_MEMSIZE);
1836                 mon->m_zlib = mm_create(mon->m_zback, 20 * MM_MEMSIZE);
1837
1838                 /* Compression needs to share state across borders */
1839                 mm_init_compression(mon->m_zlib);
1840         }
1841
1842         return mon;
1843 }
1844
1845 void
1846 monitor_reinit(struct monitor *mon)
1847 {
1848         int pair[2];
1849
1850         monitor_socketpair(pair);
1851
1852         mon->m_recvfd = pair[0];
1853         mon->m_sendfd = pair[1];
1854 }
1855
1856 #ifdef GSSAPI
1857 int
1858 mm_answer_gss_setup_ctx(int sock, Buffer *m)
1859 {
1860         gss_OID_desc goid;
1861         OM_uint32 major;
1862         u_int len;
1863
1864         goid.elements = buffer_get_string(m, &len);
1865         goid.length = len;
1866
1867         major = ssh_gssapi_server_ctx(&gsscontext, &goid);
1868
1869         xfree(goid.elements);
1870
1871         buffer_clear(m);
1872         buffer_put_int(m, major);
1873
1874         mm_request_send(sock, MONITOR_ANS_GSSSETUP, m);
1875
1876         /* Now we have a context, enable the step */
1877         monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 1);
1878
1879         return (0);
1880 }
1881
1882 int
1883 mm_answer_gss_accept_ctx(int sock, Buffer *m)
1884 {
1885         gss_buffer_desc in;
1886         gss_buffer_desc out = GSS_C_EMPTY_BUFFER;
1887         OM_uint32 major, minor;
1888         OM_uint32 flags = 0; /* GSI needs this */
1889         u_int len;
1890
1891         in.value = buffer_get_string(m, &len);
1892         in.length = len;
1893         major = ssh_gssapi_accept_ctx(gsscontext, &in, &out, &flags);
1894         xfree(in.value);
1895
1896         buffer_clear(m);
1897         buffer_put_int(m, major);
1898         buffer_put_string(m, out.value, out.length);
1899         buffer_put_int(m, flags);
1900         mm_request_send(sock, MONITOR_ANS_GSSSTEP, m);
1901
1902         gss_release_buffer(&minor, &out);
1903
1904         if (major == GSS_S_COMPLETE) {
1905                 monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 0);
1906                 monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
1907                 monitor_permit(mon_dispatch, MONITOR_REQ_GSSCHECKMIC, 1);
1908         }
1909         return (0);
1910 }
1911
1912 int
1913 mm_answer_gss_checkmic(int sock, Buffer *m)
1914 {
1915         gss_buffer_desc gssbuf, mic;
1916         OM_uint32 ret;
1917         u_int len;
1918
1919         gssbuf.value = buffer_get_string(m, &len);
1920         gssbuf.length = len;
1921         mic.value = buffer_get_string(m, &len);
1922         mic.length = len;
1923
1924         ret = ssh_gssapi_checkmic(gsscontext, &gssbuf, &mic);
1925
1926         xfree(gssbuf.value);
1927         xfree(mic.value);
1928
1929         buffer_clear(m);
1930         buffer_put_int(m, ret);
1931
1932         mm_request_send(sock, MONITOR_ANS_GSSCHECKMIC, m);
1933
1934         if (!GSS_ERROR(ret))
1935                 monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
1936
1937         return (0);
1938 }
1939
1940 int
1941 mm_answer_gss_userok(int sock, Buffer *m)
1942 {
1943         int authenticated;
1944
1945         authenticated = authctxt->valid && ssh_gssapi_userok(authctxt->user);
1946
1947         buffer_clear(m);
1948         buffer_put_int(m, authenticated);
1949
1950         debug3("%s: sending result %d", __func__, authenticated);
1951         mm_request_send(sock, MONITOR_ANS_GSSUSEROK, m);
1952
1953         auth_method = "gssapi-with-mic";
1954
1955         /* Monitor loop will terminate if authenticated */
1956         return (authenticated);
1957 }
1958 #endif /* GSSAPI */