1 /* $OpenBSD: monitor_wrap.c,v 1.88 2016/03/07 19:02:43 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 int compat20;
89 extern z_stream incoming_stream;
90 extern z_stream outgoing_stream;
91 extern struct monitor *pmonitor;
92 extern Buffer loginmsg;
93 extern ServerOptions options;
94
95 void
mm_log_handler(LogLevel level,const char * msg,void * ctx)96 mm_log_handler(LogLevel level, const char *msg, void *ctx)
97 {
98 Buffer log_msg;
99 struct monitor *mon = (struct monitor *)ctx;
100
101 if (mon->m_log_sendfd == -1)
102 fatal("%s: no log channel", __func__);
103
104 buffer_init(&log_msg);
105 /*
106 * Placeholder for packet length. Will be filled in with the actual
107 * packet length once the packet has been constucted. This saves
108 * fragile math.
109 */
110 buffer_put_int(&log_msg, 0);
111
112 buffer_put_int(&log_msg, level);
113 buffer_put_cstring(&log_msg, msg);
114 put_u32(buffer_ptr(&log_msg), buffer_len(&log_msg) - 4);
115 if (atomicio(vwrite, mon->m_log_sendfd, buffer_ptr(&log_msg),
116 buffer_len(&log_msg)) != buffer_len(&log_msg))
117 fatal("%s: write: %s", __func__, strerror(errno));
118 buffer_free(&log_msg);
119 }
120
121 int
mm_is_monitor(void)122 mm_is_monitor(void)
123 {
124 /*
125 * m_pid is only set in the privileged part, and
126 * points to the unprivileged child.
127 */
128 return (pmonitor && pmonitor->m_pid > 0);
129 }
130
131 void
mm_request_send(int sock,enum monitor_reqtype type,Buffer * m)132 mm_request_send(int sock, enum monitor_reqtype type, Buffer *m)
133 {
134 u_int mlen = buffer_len(m);
135 u_char buf[5];
136
137 debug3("%s entering: type %d", __func__, type);
138
139 put_u32(buf, mlen + 1);
140 buf[4] = (u_char) type; /* 1st byte of payload is mesg-type */
141 if (atomicio(vwrite, sock, buf, sizeof(buf)) != sizeof(buf))
142 fatal("%s: write: %s", __func__, strerror(errno));
143 if (atomicio(vwrite, sock, buffer_ptr(m), mlen) != mlen)
144 fatal("%s: write: %s", __func__, strerror(errno));
145 }
146
147 void
mm_request_receive(int sock,Buffer * m)148 mm_request_receive(int sock, Buffer *m)
149 {
150 u_char buf[4];
151 u_int msg_len;
152
153 debug3("%s entering", __func__);
154
155 if (atomicio(read, sock, buf, sizeof(buf)) != sizeof(buf)) {
156 if (errno == EPIPE)
157 cleanup_exit(255);
158 fatal("%s: read: %s", __func__, strerror(errno));
159 }
160 msg_len = get_u32(buf);
161 if (msg_len > 256 * 1024)
162 fatal("%s: read: bad msg_len %d", __func__, msg_len);
163 buffer_clear(m);
164 buffer_append_space(m, msg_len);
165 if (atomicio(read, sock, buffer_ptr(m), msg_len) != msg_len)
166 fatal("%s: read: %s", __func__, strerror(errno));
167 }
168
169 void
mm_request_receive_expect(int sock,enum monitor_reqtype type,Buffer * m)170 mm_request_receive_expect(int sock, enum monitor_reqtype type, Buffer *m)
171 {
172 u_char rtype;
173
174 debug3("%s entering: type %d", __func__, type);
175
176 mm_request_receive(sock, m);
177 rtype = buffer_get_char(m);
178 if (rtype != type)
179 fatal("%s: read: rtype %d != type %d", __func__,
180 rtype, type);
181 }
182
183 #ifdef WITH_OPENSSL
184 DH *
mm_choose_dh(int min,int nbits,int max)185 mm_choose_dh(int min, int nbits, int max)
186 {
187 BIGNUM *p, *g;
188 int success = 0;
189 Buffer m;
190
191 buffer_init(&m);
192 buffer_put_int(&m, min);
193 buffer_put_int(&m, nbits);
194 buffer_put_int(&m, max);
195
196 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_MODULI, &m);
197
198 debug3("%s: waiting for MONITOR_ANS_MODULI", __func__);
199 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_MODULI, &m);
200
201 success = buffer_get_char(&m);
202 if (success == 0)
203 fatal("%s: MONITOR_ANS_MODULI failed", __func__);
204
205 if ((p = BN_new()) == NULL)
206 fatal("%s: BN_new failed", __func__);
207 if ((g = BN_new()) == NULL)
208 fatal("%s: BN_new failed", __func__);
209 buffer_get_bignum2(&m, p);
210 buffer_get_bignum2(&m, g);
211
212 debug3("%s: remaining %d", __func__, buffer_len(&m));
213 buffer_free(&m);
214
215 return (dh_new_group(g, p));
216 }
217 #endif
218
219 int
mm_key_sign(Key * key,u_char ** sigp,u_int * lenp,const u_char * data,u_int datalen,const char * hostkey_alg)220 mm_key_sign(Key *key, u_char **sigp, u_int *lenp,
221 const u_char *data, u_int datalen, const char *hostkey_alg)
222 {
223 struct kex *kex = *pmonitor->m_pkex;
224 Buffer m;
225
226 debug3("%s entering", __func__);
227
228 buffer_init(&m);
229 buffer_put_int(&m, kex->host_key_index(key, 0, active_state));
230 buffer_put_string(&m, data, datalen);
231 buffer_put_cstring(&m, hostkey_alg);
232
233 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SIGN, &m);
234
235 debug3("%s: waiting for MONITOR_ANS_SIGN", __func__);
236 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SIGN, &m);
237 *sigp = buffer_get_string(&m, lenp);
238 buffer_free(&m);
239
240 return (0);
241 }
242
243 struct passwd *
mm_getpwnamallow(const char * username)244 mm_getpwnamallow(const char *username)
245 {
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 /* See comment in servconf.h */
294 COPY_MATCH_STRING_OPTS();
295 #undef M_CP_STROPT
296 #undef M_CP_STRARRAYOPT
297
298 copy_set_server_options(&options, newopts, 1);
299 free(newopts);
300
301 buffer_free(&m);
302
303 return (pw);
304 }
305
306 char *
mm_auth2_read_banner(void)307 mm_auth2_read_banner(void)
308 {
309 Buffer m;
310 char *banner;
311
312 debug3("%s entering", __func__);
313
314 buffer_init(&m);
315 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTH2_READ_BANNER, &m);
316 buffer_clear(&m);
317
318 mm_request_receive_expect(pmonitor->m_recvfd,
319 MONITOR_ANS_AUTH2_READ_BANNER, &m);
320 banner = buffer_get_string(&m, NULL);
321 buffer_free(&m);
322
323 /* treat empty banner as missing banner */
324 if (strlen(banner) == 0) {
325 free(banner);
326 banner = NULL;
327 }
328 return (banner);
329 }
330
331 /* Inform the privileged process about service and style */
332
333 void
mm_inform_authserv(char * service,char * style)334 mm_inform_authserv(char *service, char *style)
335 {
336 Buffer m;
337
338 debug3("%s entering", __func__);
339
340 buffer_init(&m);
341 buffer_put_cstring(&m, service);
342 buffer_put_cstring(&m, style ? style : "");
343
344 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHSERV, &m);
345
346 buffer_free(&m);
347 }
348
349 /* Do the password authentication */
350 int
mm_auth_password(Authctxt * authctxt,char * password)351 mm_auth_password(Authctxt *authctxt, char *password)
352 {
353 Buffer m;
354 int authenticated = 0;
355
356 debug3("%s entering", __func__);
357
358 buffer_init(&m);
359 buffer_put_cstring(&m, password);
360 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHPASSWORD, &m);
361
362 debug3("%s: waiting for MONITOR_ANS_AUTHPASSWORD", __func__);
363 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_AUTHPASSWORD, &m);
364
365 authenticated = buffer_get_int(&m);
366 #ifdef USE_PAM
367 sshpam_set_maxtries_reached(buffer_get_int(&m));
368 #endif
369
370 buffer_free(&m);
371
372 debug3("%s: user %sauthenticated",
373 __func__, authenticated ? "" : "not ");
374 return (authenticated);
375 }
376
377 int
mm_user_key_allowed(struct passwd * pw,Key * key,int pubkey_auth_attempt)378 mm_user_key_allowed(struct passwd *pw, Key *key, int pubkey_auth_attempt)
379 {
380 return (mm_key_allowed(MM_USERKEY, NULL, NULL, key,
381 pubkey_auth_attempt));
382 }
383
384 int
mm_hostbased_key_allowed(struct passwd * pw,const char * user,const char * host,Key * key)385 mm_hostbased_key_allowed(struct passwd *pw, const char *user, const char *host,
386 Key *key)
387 {
388 return (mm_key_allowed(MM_HOSTKEY, user, host, key, 0));
389 }
390
391 int
mm_auth_rhosts_rsa_key_allowed(struct passwd * pw,const char * user,const char * host,Key * key)392 mm_auth_rhosts_rsa_key_allowed(struct passwd *pw, const char *user,
393 const char *host, Key *key)
394 {
395 int ret;
396
397 key->type = KEY_RSA; /* XXX hack for key_to_blob */
398 ret = mm_key_allowed(MM_RSAHOSTKEY, user, host, key, 0);
399 key->type = KEY_RSA1;
400 return (ret);
401 }
402
403 int
mm_key_allowed(enum mm_keytype type,const char * user,const char * host,Key * key,int pubkey_auth_attempt)404 mm_key_allowed(enum mm_keytype type, const char *user, const char *host,
405 Key *key, int pubkey_auth_attempt)
406 {
407 Buffer m;
408 u_char *blob;
409 u_int len;
410 int allowed = 0, have_forced = 0;
411
412 debug3("%s entering", __func__);
413
414 /* Convert the key to a blob and the pass it over */
415 if (!key_to_blob(key, &blob, &len))
416 return (0);
417
418 buffer_init(&m);
419 buffer_put_int(&m, type);
420 buffer_put_cstring(&m, user ? user : "");
421 buffer_put_cstring(&m, host ? host : "");
422 buffer_put_string(&m, blob, len);
423 buffer_put_int(&m, pubkey_auth_attempt);
424 free(blob);
425
426 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYALLOWED, &m);
427
428 debug3("%s: waiting for MONITOR_ANS_KEYALLOWED", __func__);
429 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_KEYALLOWED, &m);
430
431 allowed = buffer_get_int(&m);
432
433 /* fake forced command */
434 auth_clear_options();
435 have_forced = buffer_get_int(&m);
436 forced_command = have_forced ? xstrdup("true") : NULL;
437
438 buffer_free(&m);
439
440 return (allowed);
441 }
442
443 /*
444 * This key verify needs to send the key type along, because the
445 * privileged parent makes the decision if the key is allowed
446 * for authentication.
447 */
448
449 int
mm_key_verify(Key * key,u_char * sig,u_int siglen,u_char * data,u_int datalen)450 mm_key_verify(Key *key, u_char *sig, u_int siglen, u_char *data, u_int datalen)
451 {
452 Buffer m;
453 u_char *blob;
454 u_int len;
455 int verified = 0;
456
457 debug3("%s entering", __func__);
458
459 /* Convert the key to a blob and the pass it over */
460 if (!key_to_blob(key, &blob, &len))
461 return (0);
462
463 buffer_init(&m);
464 buffer_put_string(&m, blob, len);
465 buffer_put_string(&m, sig, siglen);
466 buffer_put_string(&m, data, datalen);
467 free(blob);
468
469 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYVERIFY, &m);
470
471 debug3("%s: waiting for MONITOR_ANS_KEYVERIFY", __func__);
472 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_KEYVERIFY, &m);
473
474 verified = buffer_get_int(&m);
475
476 buffer_free(&m);
477
478 return (verified);
479 }
480
481 void
mm_send_keystate(struct monitor * monitor)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
mm_pty_allocate(int * ptyfd,int * ttyfd,char * namebuf,size_t namebuflen)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
mm_session_pty_cleanup2(Session * s)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
mm_start_pam(Authctxt * authctxt)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
mm_do_pam_account(void)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 *
mm_sshpam_init_ctx(Authctxt * authctxt)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
mm_sshpam_query(void * ctx,char ** name,char ** info,u_int * num,char *** prompts,u_int ** echo_on)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
mm_sshpam_respond(void * ctx,u_int num,char ** resp)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
mm_sshpam_free_ctx(void * ctxtp)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
mm_terminate(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 #ifdef WITH_SSH1
714 int
mm_ssh1_session_key(BIGNUM * num)715 mm_ssh1_session_key(BIGNUM *num)
716 {
717 int rsafail;
718 Buffer m;
719
720 buffer_init(&m);
721 buffer_put_bignum2(&m, num);
722 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SESSKEY, &m);
723
724 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SESSKEY, &m);
725
726 rsafail = buffer_get_int(&m);
727 buffer_get_bignum2(&m, num);
728
729 buffer_free(&m);
730
731 return (rsafail);
732 }
733 #endif
734
735 static void
mm_chall_setup(char ** name,char ** infotxt,u_int * numprompts,char *** prompts,u_int ** echo_on)736 mm_chall_setup(char **name, char **infotxt, u_int *numprompts,
737 char ***prompts, u_int **echo_on)
738 {
739 *name = xstrdup("");
740 *infotxt = xstrdup("");
741 *numprompts = 1;
742 *prompts = xcalloc(*numprompts, sizeof(char *));
743 *echo_on = xcalloc(*numprompts, sizeof(u_int));
744 (*echo_on)[0] = 0;
745 }
746
747 int
mm_bsdauth_query(void * ctx,char ** name,char ** infotxt,u_int * numprompts,char *** prompts,u_int ** echo_on)748 mm_bsdauth_query(void *ctx, char **name, char **infotxt,
749 u_int *numprompts, char ***prompts, u_int **echo_on)
750 {
751 Buffer m;
752 u_int success;
753 char *challenge;
754
755 debug3("%s: entering", __func__);
756
757 buffer_init(&m);
758 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHQUERY, &m);
759
760 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_BSDAUTHQUERY,
761 &m);
762 success = buffer_get_int(&m);
763 if (success == 0) {
764 debug3("%s: no challenge", __func__);
765 buffer_free(&m);
766 return (-1);
767 }
768
769 /* Get the challenge, and format the response */
770 challenge = buffer_get_string(&m, NULL);
771 buffer_free(&m);
772
773 mm_chall_setup(name, infotxt, numprompts, prompts, echo_on);
774 (*prompts)[0] = challenge;
775
776 debug3("%s: received challenge: %s", __func__, challenge);
777
778 return (0);
779 }
780
781 int
mm_bsdauth_respond(void * ctx,u_int numresponses,char ** responses)782 mm_bsdauth_respond(void *ctx, u_int numresponses, char **responses)
783 {
784 Buffer m;
785 int authok;
786
787 debug3("%s: entering", __func__);
788 if (numresponses != 1)
789 return (-1);
790
791 buffer_init(&m);
792 buffer_put_cstring(&m, responses[0]);
793 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHRESPOND, &m);
794
795 mm_request_receive_expect(pmonitor->m_recvfd,
796 MONITOR_ANS_BSDAUTHRESPOND, &m);
797
798 authok = buffer_get_int(&m);
799 buffer_free(&m);
800
801 return ((authok == 0) ? -1 : 0);
802 }
803
804 #ifdef SKEY
805 int
mm_skey_query(void * ctx,char ** name,char ** infotxt,u_int * numprompts,char *** prompts,u_int ** echo_on)806 mm_skey_query(void *ctx, char **name, char **infotxt,
807 u_int *numprompts, char ***prompts, u_int **echo_on)
808 {
809 Buffer m;
810 u_int success;
811 char *challenge;
812
813 debug3("%s: entering", __func__);
814
815 buffer_init(&m);
816 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SKEYQUERY, &m);
817
818 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SKEYQUERY,
819 &m);
820 success = buffer_get_int(&m);
821 if (success == 0) {
822 debug3("%s: no challenge", __func__);
823 buffer_free(&m);
824 return (-1);
825 }
826
827 /* Get the challenge, and format the response */
828 challenge = buffer_get_string(&m, NULL);
829 buffer_free(&m);
830
831 debug3("%s: received challenge: %s", __func__, challenge);
832
833 mm_chall_setup(name, infotxt, numprompts, prompts, echo_on);
834
835 xasprintf(*prompts, "%s%s", challenge, SKEY_PROMPT);
836 free(challenge);
837
838 return (0);
839 }
840
841 int
mm_skey_respond(void * ctx,u_int numresponses,char ** responses)842 mm_skey_respond(void *ctx, u_int numresponses, char **responses)
843 {
844 Buffer m;
845 int authok;
846
847 debug3("%s: entering", __func__);
848 if (numresponses != 1)
849 return (-1);
850
851 buffer_init(&m);
852 buffer_put_cstring(&m, responses[0]);
853 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SKEYRESPOND, &m);
854
855 mm_request_receive_expect(pmonitor->m_recvfd,
856 MONITOR_ANS_SKEYRESPOND, &m);
857
858 authok = buffer_get_int(&m);
859 buffer_free(&m);
860
861 return ((authok == 0) ? -1 : 0);
862 }
863 #endif /* SKEY */
864
865 void
mm_ssh1_session_id(u_char session_id[16])866 mm_ssh1_session_id(u_char session_id[16])
867 {
868 Buffer m;
869 int i;
870
871 debug3("%s entering", __func__);
872
873 buffer_init(&m);
874 for (i = 0; i < 16; i++)
875 buffer_put_char(&m, session_id[i]);
876
877 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SESSID, &m);
878 buffer_free(&m);
879 }
880
881 #ifdef WITH_SSH1
882 int
mm_auth_rsa_key_allowed(struct passwd * pw,BIGNUM * client_n,Key ** rkey)883 mm_auth_rsa_key_allowed(struct passwd *pw, BIGNUM *client_n, Key **rkey)
884 {
885 Buffer m;
886 Key *key;
887 u_char *blob;
888 u_int blen;
889 int allowed = 0, have_forced = 0;
890
891 debug3("%s entering", __func__);
892
893 buffer_init(&m);
894 buffer_put_bignum2(&m, client_n);
895
896 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSAKEYALLOWED, &m);
897 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSAKEYALLOWED, &m);
898
899 allowed = buffer_get_int(&m);
900
901 /* fake forced command */
902 auth_clear_options();
903 have_forced = buffer_get_int(&m);
904 forced_command = have_forced ? xstrdup("true") : NULL;
905
906 if (allowed && rkey != NULL) {
907 blob = buffer_get_string(&m, &blen);
908 if ((key = key_from_blob(blob, blen)) == NULL)
909 fatal("%s: key_from_blob failed", __func__);
910 *rkey = key;
911 free(blob);
912 }
913 buffer_free(&m);
914
915 return (allowed);
916 }
917
918 BIGNUM *
mm_auth_rsa_generate_challenge(Key * key)919 mm_auth_rsa_generate_challenge(Key *key)
920 {
921 Buffer m;
922 BIGNUM *challenge;
923 u_char *blob;
924 u_int blen;
925
926 debug3("%s entering", __func__);
927
928 if ((challenge = BN_new()) == NULL)
929 fatal("%s: BN_new failed", __func__);
930
931 key->type = KEY_RSA; /* XXX cheat for key_to_blob */
932 if (key_to_blob(key, &blob, &blen) == 0)
933 fatal("%s: key_to_blob failed", __func__);
934 key->type = KEY_RSA1;
935
936 buffer_init(&m);
937 buffer_put_string(&m, blob, blen);
938 free(blob);
939
940 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSACHALLENGE, &m);
941 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSACHALLENGE, &m);
942
943 buffer_get_bignum2(&m, challenge);
944 buffer_free(&m);
945
946 return (challenge);
947 }
948
949 int
mm_auth_rsa_verify_response(Key * key,BIGNUM * p,u_char response[16])950 mm_auth_rsa_verify_response(Key *key, BIGNUM *p, u_char response[16])
951 {
952 Buffer m;
953 u_char *blob;
954 u_int blen;
955 int success = 0;
956
957 debug3("%s entering", __func__);
958
959 key->type = KEY_RSA; /* XXX cheat for key_to_blob */
960 if (key_to_blob(key, &blob, &blen) == 0)
961 fatal("%s: key_to_blob failed", __func__);
962 key->type = KEY_RSA1;
963
964 buffer_init(&m);
965 buffer_put_string(&m, blob, blen);
966 buffer_put_string(&m, response, 16);
967 free(blob);
968
969 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSARESPONSE, &m);
970 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSARESPONSE, &m);
971
972 success = buffer_get_int(&m);
973 buffer_free(&m);
974
975 return (success);
976 }
977 #endif
978
979 #ifdef SSH_AUDIT_EVENTS
980 void
mm_audit_event(ssh_audit_event_t event)981 mm_audit_event(ssh_audit_event_t event)
982 {
983 Buffer m;
984
985 debug3("%s entering", __func__);
986
987 buffer_init(&m);
988 buffer_put_int(&m, event);
989
990 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUDIT_EVENT, &m);
991 buffer_free(&m);
992 }
993
994 void
mm_audit_run_command(const char * command)995 mm_audit_run_command(const char *command)
996 {
997 Buffer m;
998
999 debug3("%s entering command %s", __func__, command);
1000
1001 buffer_init(&m);
1002 buffer_put_cstring(&m, command);
1003
1004 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUDIT_COMMAND, &m);
1005 buffer_free(&m);
1006 }
1007 #endif /* SSH_AUDIT_EVENTS */
1008
1009 #ifdef GSSAPI
1010 OM_uint32
mm_ssh_gssapi_server_ctx(Gssctxt ** ctx,gss_OID goid)1011 mm_ssh_gssapi_server_ctx(Gssctxt **ctx, gss_OID goid)
1012 {
1013 Buffer m;
1014 OM_uint32 major;
1015
1016 /* Client doesn't get to see the context */
1017 *ctx = NULL;
1018
1019 buffer_init(&m);
1020 buffer_put_string(&m, goid->elements, goid->length);
1021
1022 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSETUP, &m);
1023 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSETUP, &m);
1024
1025 major = buffer_get_int(&m);
1026
1027 buffer_free(&m);
1028 return (major);
1029 }
1030
1031 OM_uint32
mm_ssh_gssapi_accept_ctx(Gssctxt * ctx,gss_buffer_desc * in,gss_buffer_desc * out,OM_uint32 * flags)1032 mm_ssh_gssapi_accept_ctx(Gssctxt *ctx, gss_buffer_desc *in,
1033 gss_buffer_desc *out, OM_uint32 *flags)
1034 {
1035 Buffer m;
1036 OM_uint32 major;
1037 u_int len;
1038
1039 buffer_init(&m);
1040 buffer_put_string(&m, in->value, in->length);
1041
1042 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSTEP, &m);
1043 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSTEP, &m);
1044
1045 major = buffer_get_int(&m);
1046 out->value = buffer_get_string(&m, &len);
1047 out->length = len;
1048 if (flags)
1049 *flags = buffer_get_int(&m);
1050
1051 buffer_free(&m);
1052
1053 return (major);
1054 }
1055
1056 OM_uint32
mm_ssh_gssapi_checkmic(Gssctxt * ctx,gss_buffer_t gssbuf,gss_buffer_t gssmic)1057 mm_ssh_gssapi_checkmic(Gssctxt *ctx, gss_buffer_t gssbuf, gss_buffer_t gssmic)
1058 {
1059 Buffer m;
1060 OM_uint32 major;
1061
1062 buffer_init(&m);
1063 buffer_put_string(&m, gssbuf->value, gssbuf->length);
1064 buffer_put_string(&m, gssmic->value, gssmic->length);
1065
1066 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSCHECKMIC, &m);
1067 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSCHECKMIC,
1068 &m);
1069
1070 major = buffer_get_int(&m);
1071 buffer_free(&m);
1072 return(major);
1073 }
1074
1075 int
mm_ssh_gssapi_userok(char * user)1076 mm_ssh_gssapi_userok(char *user)
1077 {
1078 Buffer m;
1079 int authenticated = 0;
1080
1081 buffer_init(&m);
1082
1083 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSUSEROK, &m);
1084 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSUSEROK,
1085 &m);
1086
1087 authenticated = buffer_get_int(&m);
1088
1089 buffer_free(&m);
1090 debug3("%s: user %sauthenticated",__func__, authenticated ? "" : "not ");
1091 return (authenticated);
1092 }
1093 #endif /* GSSAPI */
1094
1095