xref: /freebsd/crypto/openssh/monitor_wrap.c (revision cbd30a72ca196976c1c700400ecd424baa1b9c16)
1 /* $OpenBSD: monitor_wrap.c,v 1.89 2016/08/13 17:47:41 markus Exp $ */
2 /*
3  * Copyright 2002 Niels Provos <provos@citi.umich.edu>
4  * Copyright 2002 Markus Friedl <markus@openbsd.org>
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26  */
27 
28 #include "includes.h"
29 
30 #include <sys/types.h>
31 #include <sys/uio.h>
32 
33 #include <errno.h>
34 #include <pwd.h>
35 #include <signal.h>
36 #include <stdarg.h>
37 #include <stdio.h>
38 #include <string.h>
39 #include <unistd.h>
40 
41 #ifdef WITH_OPENSSL
42 #include <openssl/bn.h>
43 #include <openssl/dh.h>
44 #include <openssl/evp.h>
45 #endif
46 
47 #include "openbsd-compat/sys-queue.h"
48 #include "xmalloc.h"
49 #include "ssh.h"
50 #ifdef WITH_OPENSSL
51 #include "dh.h"
52 #endif
53 #include "buffer.h"
54 #include "key.h"
55 #include "cipher.h"
56 #include "kex.h"
57 #include "hostfile.h"
58 #include "auth.h"
59 #include "auth-options.h"
60 #include "packet.h"
61 #include "mac.h"
62 #include "log.h"
63 #include "auth-pam.h"
64 #ifdef TARGET_OS_MAC    /* XXX Broken krb5 headers on Mac */
65 #undef TARGET_OS_MAC
66 #include "zlib.h"
67 #define TARGET_OS_MAC 1
68 #else
69 #include "zlib.h"
70 #endif
71 #include "monitor.h"
72 #ifdef GSSAPI
73 #include "ssh-gss.h"
74 #endif
75 #include "monitor_wrap.h"
76 #include "atomicio.h"
77 #include "monitor_fdpass.h"
78 #include "misc.h"
79 #include "uuencode.h"
80 
81 #include "channels.h"
82 #include "session.h"
83 #include "servconf.h"
84 
85 #include "ssherr.h"
86 
87 /* Imports */
88 extern z_stream incoming_stream;
89 extern z_stream outgoing_stream;
90 extern struct monitor *pmonitor;
91 extern Buffer loginmsg;
92 extern ServerOptions options;
93 
94 void
95 mm_log_handler(LogLevel level, const char *msg, void *ctx)
96 {
97 	Buffer log_msg;
98 	struct monitor *mon = (struct monitor *)ctx;
99 
100 	if (mon->m_log_sendfd == -1)
101 		fatal("%s: no log channel", __func__);
102 
103 	buffer_init(&log_msg);
104 	/*
105 	 * Placeholder for packet length. Will be filled in with the actual
106 	 * packet length once the packet has been constucted. This saves
107 	 * fragile math.
108 	 */
109 	buffer_put_int(&log_msg, 0);
110 
111 	buffer_put_int(&log_msg, level);
112 	buffer_put_cstring(&log_msg, msg);
113 	put_u32(buffer_ptr(&log_msg), buffer_len(&log_msg) - 4);
114 	if (atomicio(vwrite, mon->m_log_sendfd, buffer_ptr(&log_msg),
115 	    buffer_len(&log_msg)) != buffer_len(&log_msg))
116 		fatal("%s: write: %s", __func__, strerror(errno));
117 	buffer_free(&log_msg);
118 }
119 
120 int
121 mm_is_monitor(void)
122 {
123 	/*
124 	 * m_pid is only set in the privileged part, and
125 	 * points to the unprivileged child.
126 	 */
127 	return (pmonitor && pmonitor->m_pid > 0);
128 }
129 
130 void
131 mm_request_send(int sock, enum monitor_reqtype type, Buffer *m)
132 {
133 	u_int mlen = buffer_len(m);
134 	u_char buf[5];
135 
136 	debug3("%s entering: type %d", __func__, type);
137 
138 	put_u32(buf, mlen + 1);
139 	buf[4] = (u_char) type;		/* 1st byte of payload is mesg-type */
140 	if (atomicio(vwrite, sock, buf, sizeof(buf)) != sizeof(buf))
141 		fatal("%s: write: %s", __func__, strerror(errno));
142 	if (atomicio(vwrite, sock, buffer_ptr(m), mlen) != mlen)
143 		fatal("%s: write: %s", __func__, strerror(errno));
144 }
145 
146 void
147 mm_request_receive(int sock, Buffer *m)
148 {
149 	u_char buf[4];
150 	u_int msg_len;
151 
152 	debug3("%s entering", __func__);
153 
154 	if (atomicio(read, sock, buf, sizeof(buf)) != sizeof(buf)) {
155 		if (errno == EPIPE)
156 			cleanup_exit(255);
157 		fatal("%s: read: %s", __func__, strerror(errno));
158 	}
159 	msg_len = get_u32(buf);
160 	if (msg_len > 256 * 1024)
161 		fatal("%s: read: bad msg_len %d", __func__, msg_len);
162 	buffer_clear(m);
163 	buffer_append_space(m, msg_len);
164 	if (atomicio(read, sock, buffer_ptr(m), msg_len) != msg_len)
165 		fatal("%s: read: %s", __func__, strerror(errno));
166 }
167 
168 void
169 mm_request_receive_expect(int sock, enum monitor_reqtype type, Buffer *m)
170 {
171 	u_char rtype;
172 
173 	debug3("%s entering: type %d", __func__, type);
174 
175 	mm_request_receive(sock, m);
176 	rtype = buffer_get_char(m);
177 	if (rtype != type)
178 		fatal("%s: read: rtype %d != type %d", __func__,
179 		    rtype, type);
180 }
181 
182 #ifdef WITH_OPENSSL
183 DH *
184 mm_choose_dh(int min, int nbits, int max)
185 {
186 	BIGNUM *p, *g;
187 	int success = 0;
188 	Buffer m;
189 
190 	buffer_init(&m);
191 	buffer_put_int(&m, min);
192 	buffer_put_int(&m, nbits);
193 	buffer_put_int(&m, max);
194 
195 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_MODULI, &m);
196 
197 	debug3("%s: waiting for MONITOR_ANS_MODULI", __func__);
198 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_MODULI, &m);
199 
200 	success = buffer_get_char(&m);
201 	if (success == 0)
202 		fatal("%s: MONITOR_ANS_MODULI failed", __func__);
203 
204 	if ((p = BN_new()) == NULL)
205 		fatal("%s: BN_new failed", __func__);
206 	if ((g = BN_new()) == NULL)
207 		fatal("%s: BN_new failed", __func__);
208 	buffer_get_bignum2(&m, p);
209 	buffer_get_bignum2(&m, g);
210 
211 	debug3("%s: remaining %d", __func__, buffer_len(&m));
212 	buffer_free(&m);
213 
214 	return (dh_new_group(g, p));
215 }
216 #endif
217 
218 int
219 mm_key_sign(Key *key, u_char **sigp, u_int *lenp,
220     const u_char *data, u_int datalen, const char *hostkey_alg)
221 {
222 	struct kex *kex = *pmonitor->m_pkex;
223 	Buffer m;
224 
225 	debug3("%s entering", __func__);
226 
227 	buffer_init(&m);
228 	buffer_put_int(&m, kex->host_key_index(key, 0, active_state));
229 	buffer_put_string(&m, data, datalen);
230 	buffer_put_cstring(&m, hostkey_alg);
231 
232 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SIGN, &m);
233 
234 	debug3("%s: waiting for MONITOR_ANS_SIGN", __func__);
235 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SIGN, &m);
236 	*sigp  = buffer_get_string(&m, lenp);
237 	buffer_free(&m);
238 
239 	return (0);
240 }
241 
242 struct passwd *
243 mm_getpwnamallow(const char *username)
244 {
245 	Buffer m;
246 	struct passwd *pw;
247 	u_int len, i;
248 	ServerOptions *newopts;
249 
250 	debug3("%s entering", __func__);
251 
252 	buffer_init(&m);
253 	buffer_put_cstring(&m, username);
254 
255 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PWNAM, &m);
256 
257 	debug3("%s: waiting for MONITOR_ANS_PWNAM", __func__);
258 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PWNAM, &m);
259 
260 	if (buffer_get_char(&m) == 0) {
261 		pw = NULL;
262 		goto out;
263 	}
264 	pw = buffer_get_string(&m, &len);
265 	if (len != sizeof(struct passwd))
266 		fatal("%s: struct passwd size mismatch", __func__);
267 	pw->pw_name = buffer_get_string(&m, NULL);
268 	pw->pw_passwd = buffer_get_string(&m, NULL);
269 #ifdef HAVE_STRUCT_PASSWD_PW_GECOS
270 	pw->pw_gecos = buffer_get_string(&m, NULL);
271 #endif
272 #ifdef HAVE_STRUCT_PASSWD_PW_CLASS
273 	pw->pw_class = buffer_get_string(&m, NULL);
274 #endif
275 	pw->pw_dir = buffer_get_string(&m, NULL);
276 	pw->pw_shell = buffer_get_string(&m, NULL);
277 
278 out:
279 	/* copy options block as a Match directive may have changed some */
280 	newopts = buffer_get_string(&m, &len);
281 	if (len != sizeof(*newopts))
282 		fatal("%s: option block size mismatch", __func__);
283 
284 #define M_CP_STROPT(x) do { \
285 		if (newopts->x != NULL) \
286 			newopts->x = buffer_get_string(&m, NULL); \
287 	} while (0)
288 #define M_CP_STRARRAYOPT(x, nx) do { \
289 		for (i = 0; i < newopts->nx; i++) \
290 			newopts->x[i] = buffer_get_string(&m, NULL); \
291 	} while (0)
292 	/* See comment in servconf.h */
293 	COPY_MATCH_STRING_OPTS();
294 #undef M_CP_STROPT
295 #undef M_CP_STRARRAYOPT
296 
297 	copy_set_server_options(&options, newopts, 1);
298 	free(newopts);
299 
300 	buffer_free(&m);
301 
302 	return (pw);
303 }
304 
305 char *
306 mm_auth2_read_banner(void)
307 {
308 	Buffer m;
309 	char *banner;
310 
311 	debug3("%s entering", __func__);
312 
313 	buffer_init(&m);
314 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTH2_READ_BANNER, &m);
315 	buffer_clear(&m);
316 
317 	mm_request_receive_expect(pmonitor->m_recvfd,
318 	    MONITOR_ANS_AUTH2_READ_BANNER, &m);
319 	banner = buffer_get_string(&m, NULL);
320 	buffer_free(&m);
321 
322 	/* treat empty banner as missing banner */
323 	if (strlen(banner) == 0) {
324 		free(banner);
325 		banner = NULL;
326 	}
327 	return (banner);
328 }
329 
330 /* Inform the privileged process about service and style */
331 
332 void
333 mm_inform_authserv(char *service, char *style)
334 {
335 	Buffer m;
336 
337 	debug3("%s entering", __func__);
338 
339 	buffer_init(&m);
340 	buffer_put_cstring(&m, service);
341 	buffer_put_cstring(&m, style ? style : "");
342 
343 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHSERV, &m);
344 
345 	buffer_free(&m);
346 }
347 
348 /* Do the password authentication */
349 int
350 mm_auth_password(Authctxt *authctxt, char *password)
351 {
352 	Buffer m;
353 	int authenticated = 0;
354 
355 	debug3("%s entering", __func__);
356 
357 	buffer_init(&m);
358 	buffer_put_cstring(&m, password);
359 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHPASSWORD, &m);
360 
361 	debug3("%s: waiting for MONITOR_ANS_AUTHPASSWORD", __func__);
362 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_AUTHPASSWORD, &m);
363 
364 	authenticated = buffer_get_int(&m);
365 #ifdef USE_PAM
366 	sshpam_set_maxtries_reached(buffer_get_int(&m));
367 #endif
368 
369 	buffer_free(&m);
370 
371 	debug3("%s: user %sauthenticated",
372 	    __func__, authenticated ? "" : "not ");
373 	return (authenticated);
374 }
375 
376 int
377 mm_user_key_allowed(struct passwd *pw, Key *key, int pubkey_auth_attempt)
378 {
379 	return (mm_key_allowed(MM_USERKEY, NULL, NULL, key,
380 	    pubkey_auth_attempt));
381 }
382 
383 int
384 mm_hostbased_key_allowed(struct passwd *pw, const char *user, const char *host,
385     Key *key)
386 {
387 	return (mm_key_allowed(MM_HOSTKEY, user, host, key, 0));
388 }
389 
390 int
391 mm_key_allowed(enum mm_keytype type, const char *user, const char *host,
392     Key *key, int pubkey_auth_attempt)
393 {
394 	Buffer m;
395 	u_char *blob;
396 	u_int len;
397 	int allowed = 0, have_forced = 0;
398 
399 	debug3("%s entering", __func__);
400 
401 	/* Convert the key to a blob and the pass it over */
402 	if (!key_to_blob(key, &blob, &len))
403 		return (0);
404 
405 	buffer_init(&m);
406 	buffer_put_int(&m, type);
407 	buffer_put_cstring(&m, user ? user : "");
408 	buffer_put_cstring(&m, host ? host : "");
409 	buffer_put_string(&m, blob, len);
410 	buffer_put_int(&m, pubkey_auth_attempt);
411 	free(blob);
412 
413 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYALLOWED, &m);
414 
415 	debug3("%s: waiting for MONITOR_ANS_KEYALLOWED", __func__);
416 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_KEYALLOWED, &m);
417 
418 	allowed = buffer_get_int(&m);
419 
420 	/* fake forced command */
421 	auth_clear_options();
422 	have_forced = buffer_get_int(&m);
423 	forced_command = have_forced ? xstrdup("true") : NULL;
424 
425 	buffer_free(&m);
426 
427 	return (allowed);
428 }
429 
430 /*
431  * This key verify needs to send the key type along, because the
432  * privileged parent makes the decision if the key is allowed
433  * for authentication.
434  */
435 
436 int
437 mm_key_verify(Key *key, u_char *sig, u_int siglen, u_char *data, u_int datalen)
438 {
439 	Buffer m;
440 	u_char *blob;
441 	u_int len;
442 	int verified = 0;
443 
444 	debug3("%s entering", __func__);
445 
446 	/* Convert the key to a blob and the pass it over */
447 	if (!key_to_blob(key, &blob, &len))
448 		return (0);
449 
450 	buffer_init(&m);
451 	buffer_put_string(&m, blob, len);
452 	buffer_put_string(&m, sig, siglen);
453 	buffer_put_string(&m, data, datalen);
454 	free(blob);
455 
456 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYVERIFY, &m);
457 
458 	debug3("%s: waiting for MONITOR_ANS_KEYVERIFY", __func__);
459 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_KEYVERIFY, &m);
460 
461 	verified = buffer_get_int(&m);
462 
463 	buffer_free(&m);
464 
465 	return (verified);
466 }
467 
468 void
469 mm_send_keystate(struct monitor *monitor)
470 {
471 	struct ssh *ssh = active_state;		/* XXX */
472 	struct sshbuf *m;
473 	int r;
474 
475 	if ((m = sshbuf_new()) == NULL)
476 		fatal("%s: sshbuf_new failed", __func__);
477 	if ((r = ssh_packet_get_state(ssh, m)) != 0)
478 		fatal("%s: get_state failed: %s",
479 		    __func__, ssh_err(r));
480 	mm_request_send(monitor->m_recvfd, MONITOR_REQ_KEYEXPORT, m);
481 	debug3("%s: Finished sending state", __func__);
482 	sshbuf_free(m);
483 }
484 
485 int
486 mm_pty_allocate(int *ptyfd, int *ttyfd, char *namebuf, size_t namebuflen)
487 {
488 	Buffer m;
489 	char *p, *msg;
490 	int success = 0, tmp1 = -1, tmp2 = -1;
491 
492 	/* Kludge: ensure there are fds free to receive the pty/tty */
493 	if ((tmp1 = dup(pmonitor->m_recvfd)) == -1 ||
494 	    (tmp2 = dup(pmonitor->m_recvfd)) == -1) {
495 		error("%s: cannot allocate fds for pty", __func__);
496 		if (tmp1 > 0)
497 			close(tmp1);
498 		if (tmp2 > 0)
499 			close(tmp2);
500 		return 0;
501 	}
502 	close(tmp1);
503 	close(tmp2);
504 
505 	buffer_init(&m);
506 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTY, &m);
507 
508 	debug3("%s: waiting for MONITOR_ANS_PTY", __func__);
509 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PTY, &m);
510 
511 	success = buffer_get_int(&m);
512 	if (success == 0) {
513 		debug3("%s: pty alloc failed", __func__);
514 		buffer_free(&m);
515 		return (0);
516 	}
517 	p = buffer_get_string(&m, NULL);
518 	msg = buffer_get_string(&m, NULL);
519 	buffer_free(&m);
520 
521 	strlcpy(namebuf, p, namebuflen); /* Possible truncation */
522 	free(p);
523 
524 	buffer_append(&loginmsg, msg, strlen(msg));
525 	free(msg);
526 
527 	if ((*ptyfd = mm_receive_fd(pmonitor->m_recvfd)) == -1 ||
528 	    (*ttyfd = mm_receive_fd(pmonitor->m_recvfd)) == -1)
529 		fatal("%s: receive fds failed", __func__);
530 
531 	/* Success */
532 	return (1);
533 }
534 
535 void
536 mm_session_pty_cleanup2(Session *s)
537 {
538 	Buffer m;
539 
540 	if (s->ttyfd == -1)
541 		return;
542 	buffer_init(&m);
543 	buffer_put_cstring(&m, s->tty);
544 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTYCLEANUP, &m);
545 	buffer_free(&m);
546 
547 	/* closed dup'ed master */
548 	if (s->ptymaster != -1 && close(s->ptymaster) < 0)
549 		error("close(s->ptymaster/%d): %s",
550 		    s->ptymaster, strerror(errno));
551 
552 	/* unlink pty from session */
553 	s->ttyfd = -1;
554 }
555 
556 #ifdef USE_PAM
557 void
558 mm_start_pam(Authctxt *authctxt)
559 {
560 	Buffer m;
561 
562 	debug3("%s entering", __func__);
563 	if (!options.use_pam)
564 		fatal("UsePAM=no, but ended up in %s anyway", __func__);
565 
566 	buffer_init(&m);
567 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_START, &m);
568 
569 	buffer_free(&m);
570 }
571 
572 u_int
573 mm_do_pam_account(void)
574 {
575 	Buffer m;
576 	u_int ret;
577 	char *msg;
578 
579 	debug3("%s entering", __func__);
580 	if (!options.use_pam)
581 		fatal("UsePAM=no, but ended up in %s anyway", __func__);
582 
583 	buffer_init(&m);
584 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_ACCOUNT, &m);
585 
586 	mm_request_receive_expect(pmonitor->m_recvfd,
587 	    MONITOR_ANS_PAM_ACCOUNT, &m);
588 	ret = buffer_get_int(&m);
589 	msg = buffer_get_string(&m, NULL);
590 	buffer_append(&loginmsg, msg, strlen(msg));
591 	free(msg);
592 
593 	buffer_free(&m);
594 
595 	debug3("%s returning %d", __func__, ret);
596 
597 	return (ret);
598 }
599 
600 void *
601 mm_sshpam_init_ctx(Authctxt *authctxt)
602 {
603 	Buffer m;
604 	int success;
605 
606 	debug3("%s", __func__);
607 	buffer_init(&m);
608 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_INIT_CTX, &m);
609 	debug3("%s: waiting for MONITOR_ANS_PAM_INIT_CTX", __func__);
610 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_INIT_CTX, &m);
611 	success = buffer_get_int(&m);
612 	if (success == 0) {
613 		debug3("%s: pam_init_ctx failed", __func__);
614 		buffer_free(&m);
615 		return (NULL);
616 	}
617 	buffer_free(&m);
618 	return (authctxt);
619 }
620 
621 int
622 mm_sshpam_query(void *ctx, char **name, char **info,
623     u_int *num, char ***prompts, u_int **echo_on)
624 {
625 	Buffer m;
626 	u_int i;
627 	int ret;
628 
629 	debug3("%s", __func__);
630 	buffer_init(&m);
631 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_QUERY, &m);
632 	debug3("%s: waiting for MONITOR_ANS_PAM_QUERY", __func__);
633 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_QUERY, &m);
634 	ret = buffer_get_int(&m);
635 	debug3("%s: pam_query returned %d", __func__, ret);
636 	*name = buffer_get_string(&m, NULL);
637 	*info = buffer_get_string(&m, NULL);
638 	sshpam_set_maxtries_reached(buffer_get_int(&m));
639 	*num = buffer_get_int(&m);
640 	if (*num > PAM_MAX_NUM_MSG)
641 		fatal("%s: recieved %u PAM messages, expected <= %u",
642 		    __func__, *num, PAM_MAX_NUM_MSG);
643 	*prompts = xcalloc((*num + 1), sizeof(char *));
644 	*echo_on = xcalloc((*num + 1), sizeof(u_int));
645 	for (i = 0; i < *num; ++i) {
646 		(*prompts)[i] = buffer_get_string(&m, NULL);
647 		(*echo_on)[i] = buffer_get_int(&m);
648 	}
649 	buffer_free(&m);
650 	return (ret);
651 }
652 
653 int
654 mm_sshpam_respond(void *ctx, u_int num, char **resp)
655 {
656 	Buffer m;
657 	u_int i;
658 	int ret;
659 
660 	debug3("%s", __func__);
661 	buffer_init(&m);
662 	buffer_put_int(&m, num);
663 	for (i = 0; i < num; ++i)
664 		buffer_put_cstring(&m, resp[i]);
665 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_RESPOND, &m);
666 	debug3("%s: waiting for MONITOR_ANS_PAM_RESPOND", __func__);
667 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_RESPOND, &m);
668 	ret = buffer_get_int(&m);
669 	debug3("%s: pam_respond returned %d", __func__, ret);
670 	buffer_free(&m);
671 	return (ret);
672 }
673 
674 void
675 mm_sshpam_free_ctx(void *ctxtp)
676 {
677 	Buffer m;
678 
679 	debug3("%s", __func__);
680 	buffer_init(&m);
681 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_FREE_CTX, &m);
682 	debug3("%s: waiting for MONITOR_ANS_PAM_FREE_CTX", __func__);
683 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_FREE_CTX, &m);
684 	buffer_free(&m);
685 }
686 #endif /* USE_PAM */
687 
688 /* Request process termination */
689 
690 void
691 mm_terminate(void)
692 {
693 	Buffer m;
694 
695 	buffer_init(&m);
696 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_TERM, &m);
697 	buffer_free(&m);
698 }
699 
700 static void
701 mm_chall_setup(char **name, char **infotxt, u_int *numprompts,
702     char ***prompts, u_int **echo_on)
703 {
704 	*name = xstrdup("");
705 	*infotxt = xstrdup("");
706 	*numprompts = 1;
707 	*prompts = xcalloc(*numprompts, sizeof(char *));
708 	*echo_on = xcalloc(*numprompts, sizeof(u_int));
709 	(*echo_on)[0] = 0;
710 }
711 
712 int
713 mm_bsdauth_query(void *ctx, char **name, char **infotxt,
714    u_int *numprompts, char ***prompts, u_int **echo_on)
715 {
716 	Buffer m;
717 	u_int success;
718 	char *challenge;
719 
720 	debug3("%s: entering", __func__);
721 
722 	buffer_init(&m);
723 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHQUERY, &m);
724 
725 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_BSDAUTHQUERY,
726 	    &m);
727 	success = buffer_get_int(&m);
728 	if (success == 0) {
729 		debug3("%s: no challenge", __func__);
730 		buffer_free(&m);
731 		return (-1);
732 	}
733 
734 	/* Get the challenge, and format the response */
735 	challenge  = buffer_get_string(&m, NULL);
736 	buffer_free(&m);
737 
738 	mm_chall_setup(name, infotxt, numprompts, prompts, echo_on);
739 	(*prompts)[0] = challenge;
740 
741 	debug3("%s: received challenge: %s", __func__, challenge);
742 
743 	return (0);
744 }
745 
746 int
747 mm_bsdauth_respond(void *ctx, u_int numresponses, char **responses)
748 {
749 	Buffer m;
750 	int authok;
751 
752 	debug3("%s: entering", __func__);
753 	if (numresponses != 1)
754 		return (-1);
755 
756 	buffer_init(&m);
757 	buffer_put_cstring(&m, responses[0]);
758 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHRESPOND, &m);
759 
760 	mm_request_receive_expect(pmonitor->m_recvfd,
761 	    MONITOR_ANS_BSDAUTHRESPOND, &m);
762 
763 	authok = buffer_get_int(&m);
764 	buffer_free(&m);
765 
766 	return ((authok == 0) ? -1 : 0);
767 }
768 
769 #ifdef SKEY
770 int
771 mm_skey_query(void *ctx, char **name, char **infotxt,
772    u_int *numprompts, char ***prompts, u_int **echo_on)
773 {
774 	Buffer m;
775 	u_int success;
776 	char *challenge;
777 
778 	debug3("%s: entering", __func__);
779 
780 	buffer_init(&m);
781 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SKEYQUERY, &m);
782 
783 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SKEYQUERY,
784 	    &m);
785 	success = buffer_get_int(&m);
786 	if (success == 0) {
787 		debug3("%s: no challenge", __func__);
788 		buffer_free(&m);
789 		return (-1);
790 	}
791 
792 	/* Get the challenge, and format the response */
793 	challenge  = buffer_get_string(&m, NULL);
794 	buffer_free(&m);
795 
796 	debug3("%s: received challenge: %s", __func__, challenge);
797 
798 	mm_chall_setup(name, infotxt, numprompts, prompts, echo_on);
799 
800 	xasprintf(*prompts, "%s%s", challenge, SKEY_PROMPT);
801 	free(challenge);
802 
803 	return (0);
804 }
805 
806 int
807 mm_skey_respond(void *ctx, u_int numresponses, char **responses)
808 {
809 	Buffer m;
810 	int authok;
811 
812 	debug3("%s: entering", __func__);
813 	if (numresponses != 1)
814 		return (-1);
815 
816 	buffer_init(&m);
817 	buffer_put_cstring(&m, responses[0]);
818 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SKEYRESPOND, &m);
819 
820 	mm_request_receive_expect(pmonitor->m_recvfd,
821 	    MONITOR_ANS_SKEYRESPOND, &m);
822 
823 	authok = buffer_get_int(&m);
824 	buffer_free(&m);
825 
826 	return ((authok == 0) ? -1 : 0);
827 }
828 #endif /* SKEY */
829 
830 #ifdef SSH_AUDIT_EVENTS
831 void
832 mm_audit_event(ssh_audit_event_t event)
833 {
834 	Buffer m;
835 
836 	debug3("%s entering", __func__);
837 
838 	buffer_init(&m);
839 	buffer_put_int(&m, event);
840 
841 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUDIT_EVENT, &m);
842 	buffer_free(&m);
843 }
844 
845 void
846 mm_audit_run_command(const char *command)
847 {
848 	Buffer m;
849 
850 	debug3("%s entering command %s", __func__, command);
851 
852 	buffer_init(&m);
853 	buffer_put_cstring(&m, command);
854 
855 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUDIT_COMMAND, &m);
856 	buffer_free(&m);
857 }
858 #endif /* SSH_AUDIT_EVENTS */
859 
860 #ifdef GSSAPI
861 OM_uint32
862 mm_ssh_gssapi_server_ctx(Gssctxt **ctx, gss_OID goid)
863 {
864 	Buffer m;
865 	OM_uint32 major;
866 
867 	/* Client doesn't get to see the context */
868 	*ctx = NULL;
869 
870 	buffer_init(&m);
871 	buffer_put_string(&m, goid->elements, goid->length);
872 
873 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSETUP, &m);
874 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSETUP, &m);
875 
876 	major = buffer_get_int(&m);
877 
878 	buffer_free(&m);
879 	return (major);
880 }
881 
882 OM_uint32
883 mm_ssh_gssapi_accept_ctx(Gssctxt *ctx, gss_buffer_desc *in,
884     gss_buffer_desc *out, OM_uint32 *flags)
885 {
886 	Buffer m;
887 	OM_uint32 major;
888 	u_int len;
889 
890 	buffer_init(&m);
891 	buffer_put_string(&m, in->value, in->length);
892 
893 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSTEP, &m);
894 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSTEP, &m);
895 
896 	major = buffer_get_int(&m);
897 	out->value = buffer_get_string(&m, &len);
898 	out->length = len;
899 	if (flags)
900 		*flags = buffer_get_int(&m);
901 
902 	buffer_free(&m);
903 
904 	return (major);
905 }
906 
907 OM_uint32
908 mm_ssh_gssapi_checkmic(Gssctxt *ctx, gss_buffer_t gssbuf, gss_buffer_t gssmic)
909 {
910 	Buffer m;
911 	OM_uint32 major;
912 
913 	buffer_init(&m);
914 	buffer_put_string(&m, gssbuf->value, gssbuf->length);
915 	buffer_put_string(&m, gssmic->value, gssmic->length);
916 
917 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSCHECKMIC, &m);
918 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSCHECKMIC,
919 	    &m);
920 
921 	major = buffer_get_int(&m);
922 	buffer_free(&m);
923 	return(major);
924 }
925 
926 int
927 mm_ssh_gssapi_userok(char *user)
928 {
929 	Buffer m;
930 	int authenticated = 0;
931 
932 	buffer_init(&m);
933 
934 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSUSEROK, &m);
935 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSUSEROK,
936 				  &m);
937 
938 	authenticated = buffer_get_int(&m);
939 
940 	buffer_free(&m);
941 	debug3("%s: user %sauthenticated",__func__, authenticated ? "" : "not ");
942 	return (authenticated);
943 }
944 #endif /* GSSAPI */
945 
946