xref: /freebsd/crypto/openssh/monitor_wrap.c (revision bc5531debefeb54993d01d4f3c8b33ccbe0b4d95)
1 /* $OpenBSD: monitor_wrap.c,v 1.84 2015/02/16 22:13:32 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 #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 "monitor.h"
71 #ifdef GSSAPI
72 #include "ssh-gss.h"
73 #endif
74 #include "monitor_wrap.h"
75 #include "atomicio.h"
76 #include "monitor_fdpass.h"
77 #include "misc.h"
78 #include "uuencode.h"
79 
80 #include "channels.h"
81 #include "session.h"
82 #include "servconf.h"
83 #include "roaming.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
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
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
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
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 			error("%s: socket closed", __func__);
158 			cleanup_exit(255);
159 		}
160 		fatal("%s: read: %s", __func__, strerror(errno));
161 	}
162 	msg_len = get_u32(buf);
163 	if (msg_len > 256 * 1024)
164 		fatal("%s: read: bad msg_len %d", __func__, msg_len);
165 	buffer_clear(m);
166 	buffer_append_space(m, msg_len);
167 	if (atomicio(read, sock, buffer_ptr(m), msg_len) != msg_len)
168 		fatal("%s: read: %s", __func__, strerror(errno));
169 }
170 
171 void
172 mm_request_receive_expect(int sock, enum monitor_reqtype type, Buffer *m)
173 {
174 	u_char rtype;
175 
176 	debug3("%s entering: type %d", __func__, type);
177 
178 	mm_request_receive(sock, m);
179 	rtype = buffer_get_char(m);
180 	if (rtype != type)
181 		fatal("%s: read: rtype %d != type %d", __func__,
182 		    rtype, type);
183 }
184 
185 #ifdef WITH_OPENSSL
186 DH *
187 mm_choose_dh(int min, int nbits, int max)
188 {
189 	BIGNUM *p, *g;
190 	int success = 0;
191 	Buffer m;
192 
193 	buffer_init(&m);
194 	buffer_put_int(&m, min);
195 	buffer_put_int(&m, nbits);
196 	buffer_put_int(&m, max);
197 
198 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_MODULI, &m);
199 
200 	debug3("%s: waiting for MONITOR_ANS_MODULI", __func__);
201 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_MODULI, &m);
202 
203 	success = buffer_get_char(&m);
204 	if (success == 0)
205 		fatal("%s: MONITOR_ANS_MODULI failed", __func__);
206 
207 	if ((p = BN_new()) == NULL)
208 		fatal("%s: BN_new failed", __func__);
209 	if ((g = BN_new()) == NULL)
210 		fatal("%s: BN_new failed", __func__);
211 	buffer_get_bignum2(&m, p);
212 	buffer_get_bignum2(&m, g);
213 
214 	debug3("%s: remaining %d", __func__, buffer_len(&m));
215 	buffer_free(&m);
216 
217 	return (dh_new_group(g, p));
218 }
219 #endif
220 
221 int
222 mm_key_sign(Key *key, u_char **sigp, u_int *lenp,
223     const u_char *data, u_int datalen)
224 {
225 	struct kex *kex = *pmonitor->m_pkex;
226 	Buffer m;
227 
228 	debug3("%s entering", __func__);
229 
230 	buffer_init(&m);
231 	buffer_put_int(&m, kex->host_key_index(key, 0, active_state));
232 	buffer_put_string(&m, data, datalen);
233 
234 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SIGN, &m);
235 
236 	debug3("%s: waiting for MONITOR_ANS_SIGN", __func__);
237 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SIGN, &m);
238 	*sigp  = buffer_get_string(&m, lenp);
239 	buffer_free(&m);
240 
241 	return (0);
242 }
243 
244 struct passwd *
245 mm_getpwnamallow(const char *username)
246 {
247 	Buffer m;
248 	struct passwd *pw;
249 	u_int len, i;
250 	ServerOptions *newopts;
251 
252 	debug3("%s entering", __func__);
253 
254 	buffer_init(&m);
255 	buffer_put_cstring(&m, username);
256 
257 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PWNAM, &m);
258 
259 	debug3("%s: waiting for MONITOR_ANS_PWNAM", __func__);
260 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PWNAM, &m);
261 
262 	if (buffer_get_char(&m) == 0) {
263 		pw = NULL;
264 		goto out;
265 	}
266 	pw = buffer_get_string(&m, &len);
267 	if (len != sizeof(struct passwd))
268 		fatal("%s: struct passwd size mismatch", __func__);
269 	pw->pw_name = buffer_get_string(&m, NULL);
270 	pw->pw_passwd = buffer_get_string(&m, NULL);
271 #ifdef HAVE_STRUCT_PASSWD_PW_GECOS
272 	pw->pw_gecos = buffer_get_string(&m, NULL);
273 #endif
274 #ifdef HAVE_STRUCT_PASSWD_PW_CLASS
275 	pw->pw_class = buffer_get_string(&m, NULL);
276 #endif
277 	pw->pw_dir = buffer_get_string(&m, NULL);
278 	pw->pw_shell = buffer_get_string(&m, NULL);
279 
280 out:
281 	/* copy options block as a Match directive may have changed some */
282 	newopts = buffer_get_string(&m, &len);
283 	if (len != sizeof(*newopts))
284 		fatal("%s: option block size mismatch", __func__);
285 
286 #define M_CP_STROPT(x) do { \
287 		if (newopts->x != NULL) \
288 			newopts->x = buffer_get_string(&m, NULL); \
289 	} while (0)
290 #define M_CP_STRARRAYOPT(x, nx) do { \
291 		for (i = 0; i < newopts->nx; i++) \
292 			newopts->x[i] = buffer_get_string(&m, NULL); \
293 	} while (0)
294 	/* See comment in servconf.h */
295 	COPY_MATCH_STRING_OPTS();
296 #undef M_CP_STROPT
297 #undef M_CP_STRARRAYOPT
298 
299 	copy_set_server_options(&options, newopts, 1);
300 	free(newopts);
301 
302 	buffer_free(&m);
303 
304 	return (pw);
305 }
306 
307 char *
308 mm_auth2_read_banner(void)
309 {
310 	Buffer m;
311 	char *banner;
312 
313 	debug3("%s entering", __func__);
314 
315 	buffer_init(&m);
316 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTH2_READ_BANNER, &m);
317 	buffer_clear(&m);
318 
319 	mm_request_receive_expect(pmonitor->m_recvfd,
320 	    MONITOR_ANS_AUTH2_READ_BANNER, &m);
321 	banner = buffer_get_string(&m, NULL);
322 	buffer_free(&m);
323 
324 	/* treat empty banner as missing banner */
325 	if (strlen(banner) == 0) {
326 		free(banner);
327 		banner = NULL;
328 	}
329 	return (banner);
330 }
331 
332 /* Inform the privileged process about service and style */
333 
334 void
335 mm_inform_authserv(char *service, char *style)
336 {
337 	Buffer m;
338 
339 	debug3("%s entering", __func__);
340 
341 	buffer_init(&m);
342 	buffer_put_cstring(&m, service);
343 	buffer_put_cstring(&m, style ? style : "");
344 
345 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHSERV, &m);
346 
347 	buffer_free(&m);
348 }
349 
350 /* Do the password authentication */
351 int
352 mm_auth_password(Authctxt *authctxt, char *password)
353 {
354 	Buffer m;
355 	int authenticated = 0;
356 
357 	debug3("%s entering", __func__);
358 
359 	buffer_init(&m);
360 	buffer_put_cstring(&m, password);
361 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHPASSWORD, &m);
362 
363 	debug3("%s: waiting for MONITOR_ANS_AUTHPASSWORD", __func__);
364 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_AUTHPASSWORD, &m);
365 
366 	authenticated = buffer_get_int(&m);
367 
368 	buffer_free(&m);
369 
370 	debug3("%s: user %sauthenticated",
371 	    __func__, authenticated ? "" : "not ");
372 	return (authenticated);
373 }
374 
375 int
376 mm_user_key_allowed(struct passwd *pw, Key *key)
377 {
378 	return (mm_key_allowed(MM_USERKEY, NULL, NULL, key));
379 }
380 
381 int
382 mm_hostbased_key_allowed(struct passwd *pw, char *user, char *host,
383     Key *key)
384 {
385 	return (mm_key_allowed(MM_HOSTKEY, user, host, key));
386 }
387 
388 int
389 mm_auth_rhosts_rsa_key_allowed(struct passwd *pw, char *user,
390     char *host, Key *key)
391 {
392 	int ret;
393 
394 	key->type = KEY_RSA; /* XXX hack for key_to_blob */
395 	ret = mm_key_allowed(MM_RSAHOSTKEY, user, host, key);
396 	key->type = KEY_RSA1;
397 	return (ret);
398 }
399 
400 int
401 mm_key_allowed(enum mm_keytype type, char *user, char *host, Key *key)
402 {
403 	Buffer m;
404 	u_char *blob;
405 	u_int len;
406 	int allowed = 0, have_forced = 0;
407 
408 	debug3("%s entering", __func__);
409 
410 	/* Convert the key to a blob and the pass it over */
411 	if (!key_to_blob(key, &blob, &len))
412 		return (0);
413 
414 	buffer_init(&m);
415 	buffer_put_int(&m, type);
416 	buffer_put_cstring(&m, user ? user : "");
417 	buffer_put_cstring(&m, host ? host : "");
418 	buffer_put_string(&m, blob, len);
419 	free(blob);
420 
421 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYALLOWED, &m);
422 
423 	debug3("%s: waiting for MONITOR_ANS_KEYALLOWED", __func__);
424 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_KEYALLOWED, &m);
425 
426 	allowed = buffer_get_int(&m);
427 
428 	/* fake forced command */
429 	auth_clear_options();
430 	have_forced = buffer_get_int(&m);
431 	forced_command = have_forced ? xstrdup("true") : NULL;
432 
433 	buffer_free(&m);
434 
435 	return (allowed);
436 }
437 
438 /*
439  * This key verify needs to send the key type along, because the
440  * privileged parent makes the decision if the key is allowed
441  * for authentication.
442  */
443 
444 int
445 mm_key_verify(Key *key, u_char *sig, u_int siglen, u_char *data, u_int datalen)
446 {
447 	Buffer m;
448 	u_char *blob;
449 	u_int len;
450 	int verified = 0;
451 
452 	debug3("%s entering", __func__);
453 
454 	/* Convert the key to a blob and the pass it over */
455 	if (!key_to_blob(key, &blob, &len))
456 		return (0);
457 
458 	buffer_init(&m);
459 	buffer_put_string(&m, blob, len);
460 	buffer_put_string(&m, sig, siglen);
461 	buffer_put_string(&m, data, datalen);
462 	free(blob);
463 
464 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYVERIFY, &m);
465 
466 	debug3("%s: waiting for MONITOR_ANS_KEYVERIFY", __func__);
467 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_KEYVERIFY, &m);
468 
469 	verified = buffer_get_int(&m);
470 
471 	buffer_free(&m);
472 
473 	return (verified);
474 }
475 
476 void
477 mm_send_keystate(struct monitor *monitor)
478 {
479 	struct ssh *ssh = active_state;		/* XXX */
480 	struct sshbuf *m;
481 	int r;
482 
483 	if ((m = sshbuf_new()) == NULL)
484 		fatal("%s: sshbuf_new failed", __func__);
485 	if ((r = ssh_packet_get_state(ssh, m)) != 0)
486 		fatal("%s: get_state failed: %s",
487 		    __func__, ssh_err(r));
488 	mm_request_send(monitor->m_recvfd, MONITOR_REQ_KEYEXPORT, m);
489 	debug3("%s: Finished sending state", __func__);
490 	sshbuf_free(m);
491 }
492 
493 int
494 mm_pty_allocate(int *ptyfd, int *ttyfd, char *namebuf, size_t namebuflen)
495 {
496 	Buffer m;
497 	char *p, *msg;
498 	int success = 0, tmp1 = -1, tmp2 = -1;
499 
500 	/* Kludge: ensure there are fds free to receive the pty/tty */
501 	if ((tmp1 = dup(pmonitor->m_recvfd)) == -1 ||
502 	    (tmp2 = dup(pmonitor->m_recvfd)) == -1) {
503 		error("%s: cannot allocate fds for pty", __func__);
504 		if (tmp1 > 0)
505 			close(tmp1);
506 		if (tmp2 > 0)
507 			close(tmp2);
508 		return 0;
509 	}
510 	close(tmp1);
511 	close(tmp2);
512 
513 	buffer_init(&m);
514 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTY, &m);
515 
516 	debug3("%s: waiting for MONITOR_ANS_PTY", __func__);
517 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PTY, &m);
518 
519 	success = buffer_get_int(&m);
520 	if (success == 0) {
521 		debug3("%s: pty alloc failed", __func__);
522 		buffer_free(&m);
523 		return (0);
524 	}
525 	p = buffer_get_string(&m, NULL);
526 	msg = buffer_get_string(&m, NULL);
527 	buffer_free(&m);
528 
529 	strlcpy(namebuf, p, namebuflen); /* Possible truncation */
530 	free(p);
531 
532 	buffer_append(&loginmsg, msg, strlen(msg));
533 	free(msg);
534 
535 	if ((*ptyfd = mm_receive_fd(pmonitor->m_recvfd)) == -1 ||
536 	    (*ttyfd = mm_receive_fd(pmonitor->m_recvfd)) == -1)
537 		fatal("%s: receive fds failed", __func__);
538 
539 	/* Success */
540 	return (1);
541 }
542 
543 void
544 mm_session_pty_cleanup2(Session *s)
545 {
546 	Buffer m;
547 
548 	if (s->ttyfd == -1)
549 		return;
550 	buffer_init(&m);
551 	buffer_put_cstring(&m, s->tty);
552 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTYCLEANUP, &m);
553 	buffer_free(&m);
554 
555 	/* closed dup'ed master */
556 	if (s->ptymaster != -1 && close(s->ptymaster) < 0)
557 		error("close(s->ptymaster/%d): %s",
558 		    s->ptymaster, strerror(errno));
559 
560 	/* unlink pty from session */
561 	s->ttyfd = -1;
562 }
563 
564 #ifdef USE_PAM
565 void
566 mm_start_pam(Authctxt *authctxt)
567 {
568 	Buffer m;
569 
570 	debug3("%s entering", __func__);
571 	if (!options.use_pam)
572 		fatal("UsePAM=no, but ended up in %s anyway", __func__);
573 
574 	buffer_init(&m);
575 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_START, &m);
576 
577 	buffer_free(&m);
578 }
579 
580 u_int
581 mm_do_pam_account(void)
582 {
583 	Buffer m;
584 	u_int ret;
585 	char *msg;
586 
587 	debug3("%s entering", __func__);
588 	if (!options.use_pam)
589 		fatal("UsePAM=no, but ended up in %s anyway", __func__);
590 
591 	buffer_init(&m);
592 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_ACCOUNT, &m);
593 
594 	mm_request_receive_expect(pmonitor->m_recvfd,
595 	    MONITOR_ANS_PAM_ACCOUNT, &m);
596 	ret = buffer_get_int(&m);
597 	msg = buffer_get_string(&m, NULL);
598 	buffer_append(&loginmsg, msg, strlen(msg));
599 	free(msg);
600 
601 	buffer_free(&m);
602 
603 	debug3("%s returning %d", __func__, ret);
604 
605 	return (ret);
606 }
607 
608 void *
609 mm_sshpam_init_ctx(Authctxt *authctxt)
610 {
611 	Buffer m;
612 	int success;
613 
614 	debug3("%s", __func__);
615 	buffer_init(&m);
616 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_INIT_CTX, &m);
617 	debug3("%s: waiting for MONITOR_ANS_PAM_INIT_CTX", __func__);
618 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_INIT_CTX, &m);
619 	success = buffer_get_int(&m);
620 	if (success == 0) {
621 		debug3("%s: pam_init_ctx failed", __func__);
622 		buffer_free(&m);
623 		return (NULL);
624 	}
625 	buffer_free(&m);
626 	return (authctxt);
627 }
628 
629 int
630 mm_sshpam_query(void *ctx, char **name, char **info,
631     u_int *num, char ***prompts, u_int **echo_on)
632 {
633 	Buffer m;
634 	u_int i;
635 	int ret;
636 
637 	debug3("%s", __func__);
638 	buffer_init(&m);
639 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_QUERY, &m);
640 	debug3("%s: waiting for MONITOR_ANS_PAM_QUERY", __func__);
641 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_QUERY, &m);
642 	ret = buffer_get_int(&m);
643 	debug3("%s: pam_query returned %d", __func__, ret);
644 	*name = buffer_get_string(&m, NULL);
645 	*info = buffer_get_string(&m, NULL);
646 	*num = buffer_get_int(&m);
647 	if (*num > PAM_MAX_NUM_MSG)
648 		fatal("%s: recieved %u PAM messages, expected <= %u",
649 		    __func__, *num, PAM_MAX_NUM_MSG);
650 	*prompts = xcalloc((*num + 1), sizeof(char *));
651 	*echo_on = xcalloc((*num + 1), sizeof(u_int));
652 	for (i = 0; i < *num; ++i) {
653 		(*prompts)[i] = buffer_get_string(&m, NULL);
654 		(*echo_on)[i] = buffer_get_int(&m);
655 	}
656 	buffer_free(&m);
657 	return (ret);
658 }
659 
660 int
661 mm_sshpam_respond(void *ctx, u_int num, char **resp)
662 {
663 	Buffer m;
664 	u_int i;
665 	int ret;
666 
667 	debug3("%s", __func__);
668 	buffer_init(&m);
669 	buffer_put_int(&m, num);
670 	for (i = 0; i < num; ++i)
671 		buffer_put_cstring(&m, resp[i]);
672 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_RESPOND, &m);
673 	debug3("%s: waiting for MONITOR_ANS_PAM_RESPOND", __func__);
674 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_RESPOND, &m);
675 	ret = buffer_get_int(&m);
676 	debug3("%s: pam_respond returned %d", __func__, ret);
677 	buffer_free(&m);
678 	return (ret);
679 }
680 
681 void
682 mm_sshpam_free_ctx(void *ctxtp)
683 {
684 	Buffer m;
685 
686 	debug3("%s", __func__);
687 	buffer_init(&m);
688 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_FREE_CTX, &m);
689 	debug3("%s: waiting for MONITOR_ANS_PAM_FREE_CTX", __func__);
690 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_FREE_CTX, &m);
691 	buffer_free(&m);
692 }
693 #endif /* USE_PAM */
694 
695 /* Request process termination */
696 
697 void
698 mm_terminate(void)
699 {
700 	Buffer m;
701 
702 	buffer_init(&m);
703 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_TERM, &m);
704 	buffer_free(&m);
705 }
706 
707 #ifdef WITH_SSH1
708 int
709 mm_ssh1_session_key(BIGNUM *num)
710 {
711 	int rsafail;
712 	Buffer m;
713 
714 	buffer_init(&m);
715 	buffer_put_bignum2(&m, num);
716 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SESSKEY, &m);
717 
718 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SESSKEY, &m);
719 
720 	rsafail = buffer_get_int(&m);
721 	buffer_get_bignum2(&m, num);
722 
723 	buffer_free(&m);
724 
725 	return (rsafail);
726 }
727 #endif
728 
729 static void
730 mm_chall_setup(char **name, char **infotxt, u_int *numprompts,
731     char ***prompts, u_int **echo_on)
732 {
733 	*name = xstrdup("");
734 	*infotxt = xstrdup("");
735 	*numprompts = 1;
736 	*prompts = xcalloc(*numprompts, sizeof(char *));
737 	*echo_on = xcalloc(*numprompts, sizeof(u_int));
738 	(*echo_on)[0] = 0;
739 }
740 
741 int
742 mm_bsdauth_query(void *ctx, char **name, char **infotxt,
743    u_int *numprompts, char ***prompts, u_int **echo_on)
744 {
745 	Buffer m;
746 	u_int success;
747 	char *challenge;
748 
749 	debug3("%s: entering", __func__);
750 
751 	buffer_init(&m);
752 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHQUERY, &m);
753 
754 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_BSDAUTHQUERY,
755 	    &m);
756 	success = buffer_get_int(&m);
757 	if (success == 0) {
758 		debug3("%s: no challenge", __func__);
759 		buffer_free(&m);
760 		return (-1);
761 	}
762 
763 	/* Get the challenge, and format the response */
764 	challenge  = buffer_get_string(&m, NULL);
765 	buffer_free(&m);
766 
767 	mm_chall_setup(name, infotxt, numprompts, prompts, echo_on);
768 	(*prompts)[0] = challenge;
769 
770 	debug3("%s: received challenge: %s", __func__, challenge);
771 
772 	return (0);
773 }
774 
775 int
776 mm_bsdauth_respond(void *ctx, u_int numresponses, char **responses)
777 {
778 	Buffer m;
779 	int authok;
780 
781 	debug3("%s: entering", __func__);
782 	if (numresponses != 1)
783 		return (-1);
784 
785 	buffer_init(&m);
786 	buffer_put_cstring(&m, responses[0]);
787 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHRESPOND, &m);
788 
789 	mm_request_receive_expect(pmonitor->m_recvfd,
790 	    MONITOR_ANS_BSDAUTHRESPOND, &m);
791 
792 	authok = buffer_get_int(&m);
793 	buffer_free(&m);
794 
795 	return ((authok == 0) ? -1 : 0);
796 }
797 
798 #ifdef SKEY
799 int
800 mm_skey_query(void *ctx, char **name, char **infotxt,
801    u_int *numprompts, char ***prompts, u_int **echo_on)
802 {
803 	Buffer m;
804 	u_int success;
805 	char *challenge;
806 
807 	debug3("%s: entering", __func__);
808 
809 	buffer_init(&m);
810 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SKEYQUERY, &m);
811 
812 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SKEYQUERY,
813 	    &m);
814 	success = buffer_get_int(&m);
815 	if (success == 0) {
816 		debug3("%s: no challenge", __func__);
817 		buffer_free(&m);
818 		return (-1);
819 	}
820 
821 	/* Get the challenge, and format the response */
822 	challenge  = buffer_get_string(&m, NULL);
823 	buffer_free(&m);
824 
825 	debug3("%s: received challenge: %s", __func__, challenge);
826 
827 	mm_chall_setup(name, infotxt, numprompts, prompts, echo_on);
828 
829 	xasprintf(*prompts, "%s%s", challenge, SKEY_PROMPT);
830 	free(challenge);
831 
832 	return (0);
833 }
834 
835 int
836 mm_skey_respond(void *ctx, u_int numresponses, char **responses)
837 {
838 	Buffer m;
839 	int authok;
840 
841 	debug3("%s: entering", __func__);
842 	if (numresponses != 1)
843 		return (-1);
844 
845 	buffer_init(&m);
846 	buffer_put_cstring(&m, responses[0]);
847 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SKEYRESPOND, &m);
848 
849 	mm_request_receive_expect(pmonitor->m_recvfd,
850 	    MONITOR_ANS_SKEYRESPOND, &m);
851 
852 	authok = buffer_get_int(&m);
853 	buffer_free(&m);
854 
855 	return ((authok == 0) ? -1 : 0);
856 }
857 #endif /* SKEY */
858 
859 void
860 mm_ssh1_session_id(u_char session_id[16])
861 {
862 	Buffer m;
863 	int i;
864 
865 	debug3("%s entering", __func__);
866 
867 	buffer_init(&m);
868 	for (i = 0; i < 16; i++)
869 		buffer_put_char(&m, session_id[i]);
870 
871 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SESSID, &m);
872 	buffer_free(&m);
873 }
874 
875 #ifdef WITH_SSH1
876 int
877 mm_auth_rsa_key_allowed(struct passwd *pw, BIGNUM *client_n, Key **rkey)
878 {
879 	Buffer m;
880 	Key *key;
881 	u_char *blob;
882 	u_int blen;
883 	int allowed = 0, have_forced = 0;
884 
885 	debug3("%s entering", __func__);
886 
887 	buffer_init(&m);
888 	buffer_put_bignum2(&m, client_n);
889 
890 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSAKEYALLOWED, &m);
891 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSAKEYALLOWED, &m);
892 
893 	allowed = buffer_get_int(&m);
894 
895 	/* fake forced command */
896 	auth_clear_options();
897 	have_forced = buffer_get_int(&m);
898 	forced_command = have_forced ? xstrdup("true") : NULL;
899 
900 	if (allowed && rkey != NULL) {
901 		blob = buffer_get_string(&m, &blen);
902 		if ((key = key_from_blob(blob, blen)) == NULL)
903 			fatal("%s: key_from_blob failed", __func__);
904 		*rkey = key;
905 		free(blob);
906 	}
907 	buffer_free(&m);
908 
909 	return (allowed);
910 }
911 
912 BIGNUM *
913 mm_auth_rsa_generate_challenge(Key *key)
914 {
915 	Buffer m;
916 	BIGNUM *challenge;
917 	u_char *blob;
918 	u_int blen;
919 
920 	debug3("%s entering", __func__);
921 
922 	if ((challenge = BN_new()) == NULL)
923 		fatal("%s: BN_new failed", __func__);
924 
925 	key->type = KEY_RSA;    /* XXX cheat for key_to_blob */
926 	if (key_to_blob(key, &blob, &blen) == 0)
927 		fatal("%s: key_to_blob failed", __func__);
928 	key->type = KEY_RSA1;
929 
930 	buffer_init(&m);
931 	buffer_put_string(&m, blob, blen);
932 	free(blob);
933 
934 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSACHALLENGE, &m);
935 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSACHALLENGE, &m);
936 
937 	buffer_get_bignum2(&m, challenge);
938 	buffer_free(&m);
939 
940 	return (challenge);
941 }
942 
943 int
944 mm_auth_rsa_verify_response(Key *key, BIGNUM *p, u_char response[16])
945 {
946 	Buffer m;
947 	u_char *blob;
948 	u_int blen;
949 	int success = 0;
950 
951 	debug3("%s entering", __func__);
952 
953 	key->type = KEY_RSA;    /* XXX cheat for key_to_blob */
954 	if (key_to_blob(key, &blob, &blen) == 0)
955 		fatal("%s: key_to_blob failed", __func__);
956 	key->type = KEY_RSA1;
957 
958 	buffer_init(&m);
959 	buffer_put_string(&m, blob, blen);
960 	buffer_put_string(&m, response, 16);
961 	free(blob);
962 
963 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSARESPONSE, &m);
964 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSARESPONSE, &m);
965 
966 	success = buffer_get_int(&m);
967 	buffer_free(&m);
968 
969 	return (success);
970 }
971 #endif
972 
973 #ifdef SSH_AUDIT_EVENTS
974 void
975 mm_audit_event(ssh_audit_event_t event)
976 {
977 	Buffer m;
978 
979 	debug3("%s entering", __func__);
980 
981 	buffer_init(&m);
982 	buffer_put_int(&m, event);
983 
984 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUDIT_EVENT, &m);
985 	buffer_free(&m);
986 }
987 
988 void
989 mm_audit_run_command(const char *command)
990 {
991 	Buffer m;
992 
993 	debug3("%s entering command %s", __func__, command);
994 
995 	buffer_init(&m);
996 	buffer_put_cstring(&m, command);
997 
998 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUDIT_COMMAND, &m);
999 	buffer_free(&m);
1000 }
1001 #endif /* SSH_AUDIT_EVENTS */
1002 
1003 #ifdef GSSAPI
1004 OM_uint32
1005 mm_ssh_gssapi_server_ctx(Gssctxt **ctx, gss_OID goid)
1006 {
1007 	Buffer m;
1008 	OM_uint32 major;
1009 
1010 	/* Client doesn't get to see the context */
1011 	*ctx = NULL;
1012 
1013 	buffer_init(&m);
1014 	buffer_put_string(&m, goid->elements, goid->length);
1015 
1016 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSETUP, &m);
1017 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSETUP, &m);
1018 
1019 	major = buffer_get_int(&m);
1020 
1021 	buffer_free(&m);
1022 	return (major);
1023 }
1024 
1025 OM_uint32
1026 mm_ssh_gssapi_accept_ctx(Gssctxt *ctx, gss_buffer_desc *in,
1027     gss_buffer_desc *out, OM_uint32 *flags)
1028 {
1029 	Buffer m;
1030 	OM_uint32 major;
1031 	u_int len;
1032 
1033 	buffer_init(&m);
1034 	buffer_put_string(&m, in->value, in->length);
1035 
1036 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSTEP, &m);
1037 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSTEP, &m);
1038 
1039 	major = buffer_get_int(&m);
1040 	out->value = buffer_get_string(&m, &len);
1041 	out->length = len;
1042 	if (flags)
1043 		*flags = buffer_get_int(&m);
1044 
1045 	buffer_free(&m);
1046 
1047 	return (major);
1048 }
1049 
1050 OM_uint32
1051 mm_ssh_gssapi_checkmic(Gssctxt *ctx, gss_buffer_t gssbuf, gss_buffer_t gssmic)
1052 {
1053 	Buffer m;
1054 	OM_uint32 major;
1055 
1056 	buffer_init(&m);
1057 	buffer_put_string(&m, gssbuf->value, gssbuf->length);
1058 	buffer_put_string(&m, gssmic->value, gssmic->length);
1059 
1060 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSCHECKMIC, &m);
1061 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSCHECKMIC,
1062 	    &m);
1063 
1064 	major = buffer_get_int(&m);
1065 	buffer_free(&m);
1066 	return(major);
1067 }
1068 
1069 int
1070 mm_ssh_gssapi_userok(char *user)
1071 {
1072 	Buffer m;
1073 	int authenticated = 0;
1074 
1075 	buffer_init(&m);
1076 
1077 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSUSEROK, &m);
1078 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSUSEROK,
1079 				  &m);
1080 
1081 	authenticated = buffer_get_int(&m);
1082 
1083 	buffer_free(&m);
1084 	debug3("%s: user %sauthenticated",__func__, authenticated ? "" : "not ");
1085 	return (authenticated);
1086 }
1087 #endif /* GSSAPI */
1088 
1089