xref: /openbsd-src/usr.bin/ssh/monitor_wrap.c (revision 799f675f6700f14e59124f9825c723e9f2ce19dc)
1 /* $OpenBSD: monitor_wrap.c,v 1.54 2006/08/12 20:46:46 miod 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 <sys/types.h>
29 #include <sys/uio.h>
30 
31 #include <openssl/bn.h>
32 #include <openssl/dh.h>
33 
34 #include <errno.h>
35 #include <pwd.h>
36 #include <signal.h>
37 #include <stdio.h>
38 #include <string.h>
39 #include <unistd.h>
40 
41 #include "xmalloc.h"
42 #include "ssh.h"
43 #include "dh.h"
44 #include "buffer.h"
45 #include "key.h"
46 #include "cipher.h"
47 #include "kex.h"
48 #include "hostfile.h"
49 #include "auth.h"
50 #include "auth-options.h"
51 #include "packet.h"
52 #include "mac.h"
53 #include "log.h"
54 #include <zlib.h>
55 #include "monitor.h"
56 #ifdef GSSAPI
57 #include "ssh-gss.h"
58 #endif
59 #include "monitor_wrap.h"
60 #include "atomicio.h"
61 #include "monitor_fdpass.h"
62 #include "misc.h"
63 
64 #include "channels.h"
65 #include "session.h"
66 
67 /* Imports */
68 extern int compat20;
69 extern Newkeys *newkeys[];
70 extern z_stream incoming_stream;
71 extern z_stream outgoing_stream;
72 extern struct monitor *pmonitor;
73 extern Buffer input, output;
74 extern Buffer loginmsg;
75 
76 int
77 mm_is_monitor(void)
78 {
79 	/*
80 	 * m_pid is only set in the privileged part, and
81 	 * points to the unprivileged child.
82 	 */
83 	return (pmonitor && pmonitor->m_pid > 0);
84 }
85 
86 void
87 mm_request_send(int sock, enum monitor_reqtype type, Buffer *m)
88 {
89 	u_int mlen = buffer_len(m);
90 	u_char buf[5];
91 
92 	debug3("%s entering: type %d", __func__, type);
93 
94 	put_u32(buf, mlen + 1);
95 	buf[4] = (u_char) type;		/* 1st byte of payload is mesg-type */
96 	if (atomicio(vwrite, sock, buf, sizeof(buf)) != sizeof(buf))
97 		fatal("%s: write: %s", __func__, strerror(errno));
98 	if (atomicio(vwrite, sock, buffer_ptr(m), mlen) != mlen)
99 		fatal("%s: write: %s", __func__, strerror(errno));
100 }
101 
102 void
103 mm_request_receive(int sock, Buffer *m)
104 {
105 	u_char buf[4];
106 	u_int msg_len;
107 
108 	debug3("%s entering", __func__);
109 
110 	if (atomicio(read, sock, buf, sizeof(buf)) != sizeof(buf)) {
111 		if (errno == EPIPE)
112 			cleanup_exit(255);
113 		fatal("%s: read: %s", __func__, strerror(errno));
114 	}
115 	msg_len = get_u32(buf);
116 	if (msg_len > 256 * 1024)
117 		fatal("%s: read: bad msg_len %d", __func__, msg_len);
118 	buffer_clear(m);
119 	buffer_append_space(m, msg_len);
120 	if (atomicio(read, sock, buffer_ptr(m), msg_len) != msg_len)
121 		fatal("%s: read: %s", __func__, strerror(errno));
122 }
123 
124 void
125 mm_request_receive_expect(int sock, enum monitor_reqtype type, Buffer *m)
126 {
127 	u_char rtype;
128 
129 	debug3("%s entering: type %d", __func__, type);
130 
131 	mm_request_receive(sock, m);
132 	rtype = buffer_get_char(m);
133 	if (rtype != type)
134 		fatal("%s: read: rtype %d != type %d", __func__,
135 		    rtype, type);
136 }
137 
138 DH *
139 mm_choose_dh(int min, int nbits, int max)
140 {
141 	BIGNUM *p, *g;
142 	int success = 0;
143 	Buffer m;
144 
145 	buffer_init(&m);
146 	buffer_put_int(&m, min);
147 	buffer_put_int(&m, nbits);
148 	buffer_put_int(&m, max);
149 
150 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_MODULI, &m);
151 
152 	debug3("%s: waiting for MONITOR_ANS_MODULI", __func__);
153 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_MODULI, &m);
154 
155 	success = buffer_get_char(&m);
156 	if (success == 0)
157 		fatal("%s: MONITOR_ANS_MODULI failed", __func__);
158 
159 	if ((p = BN_new()) == NULL)
160 		fatal("%s: BN_new failed", __func__);
161 	if ((g = BN_new()) == NULL)
162 		fatal("%s: BN_new failed", __func__);
163 	buffer_get_bignum2(&m, p);
164 	buffer_get_bignum2(&m, g);
165 
166 	debug3("%s: remaining %d", __func__, buffer_len(&m));
167 	buffer_free(&m);
168 
169 	return (dh_new_group(g, p));
170 }
171 
172 int
173 mm_key_sign(Key *key, u_char **sigp, u_int *lenp, u_char *data, u_int datalen)
174 {
175 	Kex *kex = *pmonitor->m_pkex;
176 	Buffer m;
177 
178 	debug3("%s entering", __func__);
179 
180 	buffer_init(&m);
181 	buffer_put_int(&m, kex->host_key_index(key));
182 	buffer_put_string(&m, data, datalen);
183 
184 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SIGN, &m);
185 
186 	debug3("%s: waiting for MONITOR_ANS_SIGN", __func__);
187 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SIGN, &m);
188 	*sigp  = buffer_get_string(&m, lenp);
189 	buffer_free(&m);
190 
191 	return (0);
192 }
193 
194 struct passwd *
195 mm_getpwnamallow(const char *username)
196 {
197 	Buffer m;
198 	struct passwd *pw;
199 	u_int pwlen;
200 
201 	debug3("%s entering", __func__);
202 
203 	buffer_init(&m);
204 	buffer_put_cstring(&m, username);
205 
206 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PWNAM, &m);
207 
208 	debug3("%s: waiting for MONITOR_ANS_PWNAM", __func__);
209 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PWNAM, &m);
210 
211 	if (buffer_get_char(&m) == 0) {
212 		buffer_free(&m);
213 		return (NULL);
214 	}
215 	pw = buffer_get_string(&m, &pwlen);
216 	if (pwlen != sizeof(struct passwd))
217 		fatal("%s: struct passwd size mismatch", __func__);
218 	pw->pw_name = buffer_get_string(&m, NULL);
219 	pw->pw_passwd = buffer_get_string(&m, NULL);
220 	pw->pw_gecos = buffer_get_string(&m, NULL);
221 	pw->pw_class = buffer_get_string(&m, NULL);
222 	pw->pw_dir = buffer_get_string(&m, NULL);
223 	pw->pw_shell = buffer_get_string(&m, NULL);
224 	buffer_free(&m);
225 
226 	return (pw);
227 }
228 
229 char *
230 mm_auth2_read_banner(void)
231 {
232 	Buffer m;
233 	char *banner;
234 
235 	debug3("%s entering", __func__);
236 
237 	buffer_init(&m);
238 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTH2_READ_BANNER, &m);
239 	buffer_clear(&m);
240 
241 	mm_request_receive_expect(pmonitor->m_recvfd,
242 	    MONITOR_ANS_AUTH2_READ_BANNER, &m);
243 	banner = buffer_get_string(&m, NULL);
244 	buffer_free(&m);
245 
246 	/* treat empty banner as missing banner */
247 	if (strlen(banner) == 0) {
248 		xfree(banner);
249 		banner = NULL;
250 	}
251 	return (banner);
252 }
253 
254 /* Inform the privileged process about service and style */
255 
256 void
257 mm_inform_authserv(char *service, char *style)
258 {
259 	Buffer m;
260 
261 	debug3("%s entering", __func__);
262 
263 	buffer_init(&m);
264 	buffer_put_cstring(&m, service);
265 	buffer_put_cstring(&m, style ? style : "");
266 
267 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHSERV, &m);
268 
269 	buffer_free(&m);
270 }
271 
272 /* Do the password authentication */
273 int
274 mm_auth_password(Authctxt *authctxt, char *password)
275 {
276 	Buffer m;
277 	int authenticated = 0;
278 
279 	debug3("%s entering", __func__);
280 
281 	buffer_init(&m);
282 	buffer_put_cstring(&m, password);
283 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHPASSWORD, &m);
284 
285 	debug3("%s: waiting for MONITOR_ANS_AUTHPASSWORD", __func__);
286 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_AUTHPASSWORD, &m);
287 
288 	authenticated = buffer_get_int(&m);
289 
290 	buffer_free(&m);
291 
292 	debug3("%s: user %sauthenticated",
293 	    __func__, authenticated ? "" : "not ");
294 	return (authenticated);
295 }
296 
297 int
298 mm_user_key_allowed(struct passwd *pw, Key *key)
299 {
300 	return (mm_key_allowed(MM_USERKEY, NULL, NULL, key));
301 }
302 
303 int
304 mm_hostbased_key_allowed(struct passwd *pw, char *user, char *host,
305     Key *key)
306 {
307 	return (mm_key_allowed(MM_HOSTKEY, user, host, key));
308 }
309 
310 int
311 mm_auth_rhosts_rsa_key_allowed(struct passwd *pw, char *user,
312     char *host, Key *key)
313 {
314 	int ret;
315 
316 	key->type = KEY_RSA; /* XXX hack for key_to_blob */
317 	ret = mm_key_allowed(MM_RSAHOSTKEY, user, host, key);
318 	key->type = KEY_RSA1;
319 	return (ret);
320 }
321 
322 static void
323 mm_send_debug(Buffer *m)
324 {
325 	char *msg;
326 
327 	while (buffer_len(m)) {
328 		msg = buffer_get_string(m, NULL);
329 		debug3("%s: Sending debug: %s", __func__, msg);
330 		packet_send_debug("%s", msg);
331 		xfree(msg);
332 	}
333 }
334 
335 int
336 mm_key_allowed(enum mm_keytype type, char *user, char *host, Key *key)
337 {
338 	Buffer m;
339 	u_char *blob;
340 	u_int len;
341 	int allowed = 0, have_forced = 0;
342 
343 	debug3("%s entering", __func__);
344 
345 	/* Convert the key to a blob and the pass it over */
346 	if (!key_to_blob(key, &blob, &len))
347 		return (0);
348 
349 	buffer_init(&m);
350 	buffer_put_int(&m, type);
351 	buffer_put_cstring(&m, user ? user : "");
352 	buffer_put_cstring(&m, host ? host : "");
353 	buffer_put_string(&m, blob, len);
354 	xfree(blob);
355 
356 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYALLOWED, &m);
357 
358 	debug3("%s: waiting for MONITOR_ANS_KEYALLOWED", __func__);
359 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_KEYALLOWED, &m);
360 
361 	allowed = buffer_get_int(&m);
362 
363 	/* fake forced command */
364 	auth_clear_options();
365 	have_forced = buffer_get_int(&m);
366 	forced_command = have_forced ? xstrdup("true") : NULL;
367 
368 	/* Send potential debug messages */
369 	mm_send_debug(&m);
370 
371 	buffer_free(&m);
372 
373 	return (allowed);
374 }
375 
376 /*
377  * This key verify needs to send the key type along, because the
378  * privileged parent makes the decision if the key is allowed
379  * for authentication.
380  */
381 
382 int
383 mm_key_verify(Key *key, u_char *sig, u_int siglen, u_char *data, u_int datalen)
384 {
385 	Buffer m;
386 	u_char *blob;
387 	u_int len;
388 	int verified = 0;
389 
390 	debug3("%s entering", __func__);
391 
392 	/* Convert the key to a blob and the pass it over */
393 	if (!key_to_blob(key, &blob, &len))
394 		return (0);
395 
396 	buffer_init(&m);
397 	buffer_put_string(&m, blob, len);
398 	buffer_put_string(&m, sig, siglen);
399 	buffer_put_string(&m, data, datalen);
400 	xfree(blob);
401 
402 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYVERIFY, &m);
403 
404 	debug3("%s: waiting for MONITOR_ANS_KEYVERIFY", __func__);
405 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_KEYVERIFY, &m);
406 
407 	verified = buffer_get_int(&m);
408 
409 	buffer_free(&m);
410 
411 	return (verified);
412 }
413 
414 /* Export key state after authentication */
415 Newkeys *
416 mm_newkeys_from_blob(u_char *blob, int blen)
417 {
418 	Buffer b;
419 	u_int len;
420 	Newkeys *newkey = NULL;
421 	Enc *enc;
422 	Mac *mac;
423 	Comp *comp;
424 
425 	debug3("%s: %p(%d)", __func__, blob, blen);
426 #ifdef DEBUG_PK
427 	dump_base64(stderr, blob, blen);
428 #endif
429 	buffer_init(&b);
430 	buffer_append(&b, blob, blen);
431 
432 	newkey = xmalloc(sizeof(*newkey));
433 	enc = &newkey->enc;
434 	mac = &newkey->mac;
435 	comp = &newkey->comp;
436 
437 	/* Enc structure */
438 	enc->name = buffer_get_string(&b, NULL);
439 	buffer_get(&b, &enc->cipher, sizeof(enc->cipher));
440 	enc->enabled = buffer_get_int(&b);
441 	enc->block_size = buffer_get_int(&b);
442 	enc->key = buffer_get_string(&b, &enc->key_len);
443 	enc->iv = buffer_get_string(&b, &len);
444 	if (len != enc->block_size)
445 		fatal("%s: bad ivlen: expected %u != %u", __func__,
446 		    enc->block_size, len);
447 
448 	if (enc->name == NULL || cipher_by_name(enc->name) != enc->cipher)
449 		fatal("%s: bad cipher name %s or pointer %p", __func__,
450 		    enc->name, enc->cipher);
451 
452 	/* Mac structure */
453 	mac->name = buffer_get_string(&b, NULL);
454 	if (mac->name == NULL || mac_init(mac, mac->name) == -1)
455 		fatal("%s: can not init mac %s", __func__, mac->name);
456 	mac->enabled = buffer_get_int(&b);
457 	mac->key = buffer_get_string(&b, &len);
458 	if (len > mac->key_len)
459 		fatal("%s: bad mac key length: %u > %d", __func__, len,
460 		    mac->key_len);
461 	mac->key_len = len;
462 
463 	/* Comp structure */
464 	comp->type = buffer_get_int(&b);
465 	comp->enabled = buffer_get_int(&b);
466 	comp->name = buffer_get_string(&b, NULL);
467 
468 	len = buffer_len(&b);
469 	if (len != 0)
470 		error("newkeys_from_blob: remaining bytes in blob %u", len);
471 	buffer_free(&b);
472 	return (newkey);
473 }
474 
475 int
476 mm_newkeys_to_blob(int mode, u_char **blobp, u_int *lenp)
477 {
478 	Buffer b;
479 	int len;
480 	Enc *enc;
481 	Mac *mac;
482 	Comp *comp;
483 	Newkeys *newkey = newkeys[mode];
484 
485 	debug3("%s: converting %p", __func__, newkey);
486 
487 	if (newkey == NULL) {
488 		error("%s: newkey == NULL", __func__);
489 		return 0;
490 	}
491 	enc = &newkey->enc;
492 	mac = &newkey->mac;
493 	comp = &newkey->comp;
494 
495 	buffer_init(&b);
496 	/* Enc structure */
497 	buffer_put_cstring(&b, enc->name);
498 	/* The cipher struct is constant and shared, you export pointer */
499 	buffer_append(&b, &enc->cipher, sizeof(enc->cipher));
500 	buffer_put_int(&b, enc->enabled);
501 	buffer_put_int(&b, enc->block_size);
502 	buffer_put_string(&b, enc->key, enc->key_len);
503 	packet_get_keyiv(mode, enc->iv, enc->block_size);
504 	buffer_put_string(&b, enc->iv, enc->block_size);
505 
506 	/* Mac structure */
507 	buffer_put_cstring(&b, mac->name);
508 	buffer_put_int(&b, mac->enabled);
509 	buffer_put_string(&b, mac->key, mac->key_len);
510 
511 	/* Comp structure */
512 	buffer_put_int(&b, comp->type);
513 	buffer_put_int(&b, comp->enabled);
514 	buffer_put_cstring(&b, comp->name);
515 
516 	len = buffer_len(&b);
517 	if (lenp != NULL)
518 		*lenp = len;
519 	if (blobp != NULL) {
520 		*blobp = xmalloc(len);
521 		memcpy(*blobp, buffer_ptr(&b), len);
522 	}
523 	memset(buffer_ptr(&b), 0, len);
524 	buffer_free(&b);
525 	return len;
526 }
527 
528 static void
529 mm_send_kex(Buffer *m, Kex *kex)
530 {
531 	buffer_put_string(m, kex->session_id, kex->session_id_len);
532 	buffer_put_int(m, kex->we_need);
533 	buffer_put_int(m, kex->hostkey_type);
534 	buffer_put_int(m, kex->kex_type);
535 	buffer_put_string(m, buffer_ptr(&kex->my), buffer_len(&kex->my));
536 	buffer_put_string(m, buffer_ptr(&kex->peer), buffer_len(&kex->peer));
537 	buffer_put_int(m, kex->flags);
538 	buffer_put_cstring(m, kex->client_version_string);
539 	buffer_put_cstring(m, kex->server_version_string);
540 }
541 
542 void
543 mm_send_keystate(struct monitor *monitor)
544 {
545 	Buffer m;
546 	u_char *blob, *p;
547 	u_int bloblen, plen;
548 	u_int32_t seqnr, packets;
549 	u_int64_t blocks;
550 
551 	buffer_init(&m);
552 
553 	if (!compat20) {
554 		u_char iv[24];
555 		u_char *key;
556 		u_int ivlen, keylen;
557 
558 		buffer_put_int(&m, packet_get_protocol_flags());
559 
560 		buffer_put_int(&m, packet_get_ssh1_cipher());
561 
562 		debug3("%s: Sending ssh1 KEY+IV", __func__);
563 		keylen = packet_get_encryption_key(NULL);
564 		key = xmalloc(keylen+1);	/* add 1 if keylen == 0 */
565 		keylen = packet_get_encryption_key(key);
566 		buffer_put_string(&m, key, keylen);
567 		memset(key, 0, keylen);
568 		xfree(key);
569 
570 		ivlen = packet_get_keyiv_len(MODE_OUT);
571 		packet_get_keyiv(MODE_OUT, iv, ivlen);
572 		buffer_put_string(&m, iv, ivlen);
573 		ivlen = packet_get_keyiv_len(MODE_OUT);
574 		packet_get_keyiv(MODE_IN, iv, ivlen);
575 		buffer_put_string(&m, iv, ivlen);
576 		goto skip;
577 	} else {
578 		/* Kex for rekeying */
579 		mm_send_kex(&m, *monitor->m_pkex);
580 	}
581 
582 	debug3("%s: Sending new keys: %p %p",
583 	    __func__, newkeys[MODE_OUT], newkeys[MODE_IN]);
584 
585 	/* Keys from Kex */
586 	if (!mm_newkeys_to_blob(MODE_OUT, &blob, &bloblen))
587 		fatal("%s: conversion of newkeys failed", __func__);
588 
589 	buffer_put_string(&m, blob, bloblen);
590 	xfree(blob);
591 
592 	if (!mm_newkeys_to_blob(MODE_IN, &blob, &bloblen))
593 		fatal("%s: conversion of newkeys failed", __func__);
594 
595 	buffer_put_string(&m, blob, bloblen);
596 	xfree(blob);
597 
598 	packet_get_state(MODE_OUT, &seqnr, &blocks, &packets);
599 	buffer_put_int(&m, seqnr);
600 	buffer_put_int64(&m, blocks);
601 	buffer_put_int(&m, packets);
602 	packet_get_state(MODE_IN, &seqnr, &blocks, &packets);
603 	buffer_put_int(&m, seqnr);
604 	buffer_put_int64(&m, blocks);
605 	buffer_put_int(&m, packets);
606 
607 	debug3("%s: New keys have been sent", __func__);
608  skip:
609 	/* More key context */
610 	plen = packet_get_keycontext(MODE_OUT, NULL);
611 	p = xmalloc(plen+1);
612 	packet_get_keycontext(MODE_OUT, p);
613 	buffer_put_string(&m, p, plen);
614 	xfree(p);
615 
616 	plen = packet_get_keycontext(MODE_IN, NULL);
617 	p = xmalloc(plen+1);
618 	packet_get_keycontext(MODE_IN, p);
619 	buffer_put_string(&m, p, plen);
620 	xfree(p);
621 
622 	/* Compression state */
623 	debug3("%s: Sending compression state", __func__);
624 	buffer_put_string(&m, &outgoing_stream, sizeof(outgoing_stream));
625 	buffer_put_string(&m, &incoming_stream, sizeof(incoming_stream));
626 
627 	/* Network I/O buffers */
628 	buffer_put_string(&m, buffer_ptr(&input), buffer_len(&input));
629 	buffer_put_string(&m, buffer_ptr(&output), buffer_len(&output));
630 
631 	mm_request_send(monitor->m_recvfd, MONITOR_REQ_KEYEXPORT, &m);
632 	debug3("%s: Finished sending state", __func__);
633 
634 	buffer_free(&m);
635 }
636 
637 int
638 mm_pty_allocate(int *ptyfd, int *ttyfd, char *namebuf, size_t namebuflen)
639 {
640 	Buffer m;
641 	char *p, *msg;
642 	int success = 0;
643 
644 	buffer_init(&m);
645 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTY, &m);
646 
647 	debug3("%s: waiting for MONITOR_ANS_PTY", __func__);
648 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PTY, &m);
649 
650 	success = buffer_get_int(&m);
651 	if (success == 0) {
652 		debug3("%s: pty alloc failed", __func__);
653 		buffer_free(&m);
654 		return (0);
655 	}
656 	p = buffer_get_string(&m, NULL);
657 	msg = buffer_get_string(&m, NULL);
658 	buffer_free(&m);
659 
660 	strlcpy(namebuf, p, namebuflen); /* Possible truncation */
661 	xfree(p);
662 
663 	buffer_append(&loginmsg, msg, strlen(msg));
664 	xfree(msg);
665 
666 	*ptyfd = mm_receive_fd(pmonitor->m_recvfd);
667 	*ttyfd = mm_receive_fd(pmonitor->m_recvfd);
668 
669 	/* Success */
670 	return (1);
671 }
672 
673 void
674 mm_session_pty_cleanup2(Session *s)
675 {
676 	Buffer m;
677 
678 	if (s->ttyfd == -1)
679 		return;
680 	buffer_init(&m);
681 	buffer_put_cstring(&m, s->tty);
682 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTYCLEANUP, &m);
683 	buffer_free(&m);
684 
685 	/* closed dup'ed master */
686 	if (close(s->ptymaster) < 0)
687 		error("close(s->ptymaster): %s", strerror(errno));
688 
689 	/* unlink pty from session */
690 	s->ttyfd = -1;
691 }
692 
693 /* Request process termination */
694 
695 void
696 mm_terminate(void)
697 {
698 	Buffer m;
699 
700 	buffer_init(&m);
701 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_TERM, &m);
702 	buffer_free(&m);
703 }
704 
705 int
706 mm_ssh1_session_key(BIGNUM *num)
707 {
708 	int rsafail;
709 	Buffer m;
710 
711 	buffer_init(&m);
712 	buffer_put_bignum2(&m, num);
713 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SESSKEY, &m);
714 
715 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SESSKEY, &m);
716 
717 	rsafail = buffer_get_int(&m);
718 	buffer_get_bignum2(&m, num);
719 
720 	buffer_free(&m);
721 
722 	return (rsafail);
723 }
724 
725 static void
726 mm_chall_setup(char **name, char **infotxt, u_int *numprompts,
727     char ***prompts, u_int **echo_on)
728 {
729 	*name = xstrdup("");
730 	*infotxt = xstrdup("");
731 	*numprompts = 1;
732 	*prompts = xcalloc(*numprompts, sizeof(char *));
733 	*echo_on = xcalloc(*numprompts, sizeof(u_int));
734 	(*echo_on)[0] = 0;
735 }
736 
737 int
738 mm_bsdauth_query(void *ctx, char **name, char **infotxt,
739    u_int *numprompts, char ***prompts, u_int **echo_on)
740 {
741 	Buffer m;
742 	u_int success;
743 	char *challenge;
744 
745 	debug3("%s: entering", __func__);
746 
747 	buffer_init(&m);
748 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHQUERY, &m);
749 
750 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_BSDAUTHQUERY,
751 	    &m);
752 	success = buffer_get_int(&m);
753 	if (success == 0) {
754 		debug3("%s: no challenge", __func__);
755 		buffer_free(&m);
756 		return (-1);
757 	}
758 
759 	/* Get the challenge, and format the response */
760 	challenge  = buffer_get_string(&m, NULL);
761 	buffer_free(&m);
762 
763 	mm_chall_setup(name, infotxt, numprompts, prompts, echo_on);
764 	(*prompts)[0] = challenge;
765 
766 	debug3("%s: received challenge: %s", __func__, challenge);
767 
768 	return (0);
769 }
770 
771 int
772 mm_bsdauth_respond(void *ctx, u_int numresponses, char **responses)
773 {
774 	Buffer m;
775 	int authok;
776 
777 	debug3("%s: entering", __func__);
778 	if (numresponses != 1)
779 		return (-1);
780 
781 	buffer_init(&m);
782 	buffer_put_cstring(&m, responses[0]);
783 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHRESPOND, &m);
784 
785 	mm_request_receive_expect(pmonitor->m_recvfd,
786 	    MONITOR_ANS_BSDAUTHRESPOND, &m);
787 
788 	authok = buffer_get_int(&m);
789 	buffer_free(&m);
790 
791 	return ((authok == 0) ? -1 : 0);
792 }
793 
794 #ifdef SKEY
795 int
796 mm_skey_query(void *ctx, char **name, char **infotxt,
797    u_int *numprompts, char ***prompts, u_int **echo_on)
798 {
799 	Buffer m;
800 	u_int success;
801 	char *challenge;
802 
803 	debug3("%s: entering", __func__);
804 
805 	buffer_init(&m);
806 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SKEYQUERY, &m);
807 
808 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SKEYQUERY,
809 	    &m);
810 	success = buffer_get_int(&m);
811 	if (success == 0) {
812 		debug3("%s: no challenge", __func__);
813 		buffer_free(&m);
814 		return (-1);
815 	}
816 
817 	/* Get the challenge, and format the response */
818 	challenge  = buffer_get_string(&m, NULL);
819 	buffer_free(&m);
820 
821 	debug3("%s: received challenge: %s", __func__, challenge);
822 
823 	mm_chall_setup(name, infotxt, numprompts, prompts, echo_on);
824 
825 	xasprintf(*prompts, "%s%s", challenge, SKEY_PROMPT);
826 	xfree(challenge);
827 
828 	return (0);
829 }
830 
831 int
832 mm_skey_respond(void *ctx, u_int numresponses, char **responses)
833 {
834 	Buffer m;
835 	int authok;
836 
837 	debug3("%s: entering", __func__);
838 	if (numresponses != 1)
839 		return (-1);
840 
841 	buffer_init(&m);
842 	buffer_put_cstring(&m, responses[0]);
843 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SKEYRESPOND, &m);
844 
845 	mm_request_receive_expect(pmonitor->m_recvfd,
846 	    MONITOR_ANS_SKEYRESPOND, &m);
847 
848 	authok = buffer_get_int(&m);
849 	buffer_free(&m);
850 
851 	return ((authok == 0) ? -1 : 0);
852 }
853 #endif /* SKEY */
854 
855 void
856 mm_ssh1_session_id(u_char session_id[16])
857 {
858 	Buffer m;
859 	int i;
860 
861 	debug3("%s entering", __func__);
862 
863 	buffer_init(&m);
864 	for (i = 0; i < 16; i++)
865 		buffer_put_char(&m, session_id[i]);
866 
867 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SESSID, &m);
868 	buffer_free(&m);
869 }
870 
871 int
872 mm_auth_rsa_key_allowed(struct passwd *pw, BIGNUM *client_n, Key **rkey)
873 {
874 	Buffer m;
875 	Key *key;
876 	u_char *blob;
877 	u_int blen;
878 	int allowed = 0, have_forced = 0;
879 
880 	debug3("%s entering", __func__);
881 
882 	buffer_init(&m);
883 	buffer_put_bignum2(&m, client_n);
884 
885 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSAKEYALLOWED, &m);
886 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSAKEYALLOWED, &m);
887 
888 	allowed = buffer_get_int(&m);
889 
890 	/* fake forced command */
891 	auth_clear_options();
892 	have_forced = buffer_get_int(&m);
893 	forced_command = have_forced ? xstrdup("true") : NULL;
894 
895 	if (allowed && rkey != NULL) {
896 		blob = buffer_get_string(&m, &blen);
897 		if ((key = key_from_blob(blob, blen)) == NULL)
898 			fatal("%s: key_from_blob failed", __func__);
899 		*rkey = key;
900 		xfree(blob);
901 	}
902 	mm_send_debug(&m);
903 	buffer_free(&m);
904 
905 	return (allowed);
906 }
907 
908 BIGNUM *
909 mm_auth_rsa_generate_challenge(Key *key)
910 {
911 	Buffer m;
912 	BIGNUM *challenge;
913 	u_char *blob;
914 	u_int blen;
915 
916 	debug3("%s entering", __func__);
917 
918 	if ((challenge = BN_new()) == NULL)
919 		fatal("%s: BN_new failed", __func__);
920 
921 	key->type = KEY_RSA;    /* XXX cheat for key_to_blob */
922 	if (key_to_blob(key, &blob, &blen) == 0)
923 		fatal("%s: key_to_blob failed", __func__);
924 	key->type = KEY_RSA1;
925 
926 	buffer_init(&m);
927 	buffer_put_string(&m, blob, blen);
928 	xfree(blob);
929 
930 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSACHALLENGE, &m);
931 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSACHALLENGE, &m);
932 
933 	buffer_get_bignum2(&m, challenge);
934 	buffer_free(&m);
935 
936 	return (challenge);
937 }
938 
939 int
940 mm_auth_rsa_verify_response(Key *key, BIGNUM *p, u_char response[16])
941 {
942 	Buffer m;
943 	u_char *blob;
944 	u_int blen;
945 	int success = 0;
946 
947 	debug3("%s entering", __func__);
948 
949 	key->type = KEY_RSA;    /* XXX cheat for key_to_blob */
950 	if (key_to_blob(key, &blob, &blen) == 0)
951 		fatal("%s: key_to_blob failed", __func__);
952 	key->type = KEY_RSA1;
953 
954 	buffer_init(&m);
955 	buffer_put_string(&m, blob, blen);
956 	buffer_put_string(&m, response, 16);
957 	xfree(blob);
958 
959 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSARESPONSE, &m);
960 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSARESPONSE, &m);
961 
962 	success = buffer_get_int(&m);
963 	buffer_free(&m);
964 
965 	return (success);
966 }
967 
968 #ifdef GSSAPI
969 OM_uint32
970 mm_ssh_gssapi_server_ctx(Gssctxt **ctx, gss_OID goid)
971 {
972 	Buffer m;
973 	OM_uint32 major;
974 
975 	/* Client doesn't get to see the context */
976 	*ctx = NULL;
977 
978 	buffer_init(&m);
979 	buffer_put_string(&m, goid->elements, goid->length);
980 
981 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSETUP, &m);
982 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSETUP, &m);
983 
984 	major = buffer_get_int(&m);
985 
986 	buffer_free(&m);
987 	return (major);
988 }
989 
990 OM_uint32
991 mm_ssh_gssapi_accept_ctx(Gssctxt *ctx, gss_buffer_desc *in,
992     gss_buffer_desc *out, OM_uint32 *flags)
993 {
994 	Buffer m;
995 	OM_uint32 major;
996 	u_int len;
997 
998 	buffer_init(&m);
999 	buffer_put_string(&m, in->value, in->length);
1000 
1001 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSTEP, &m);
1002 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSTEP, &m);
1003 
1004 	major = buffer_get_int(&m);
1005 	out->value = buffer_get_string(&m, &len);
1006 	out->length = len;
1007 	if (flags)
1008 		*flags = buffer_get_int(&m);
1009 
1010 	buffer_free(&m);
1011 
1012 	return (major);
1013 }
1014 
1015 OM_uint32
1016 mm_ssh_gssapi_checkmic(Gssctxt *ctx, gss_buffer_t gssbuf, gss_buffer_t gssmic)
1017 {
1018 	Buffer m;
1019 	OM_uint32 major;
1020 
1021 	buffer_init(&m);
1022 	buffer_put_string(&m, gssbuf->value, gssbuf->length);
1023 	buffer_put_string(&m, gssmic->value, gssmic->length);
1024 
1025 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSCHECKMIC, &m);
1026 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSCHECKMIC,
1027 	    &m);
1028 
1029 	major = buffer_get_int(&m);
1030 	buffer_free(&m);
1031 	return(major);
1032 }
1033 
1034 int
1035 mm_ssh_gssapi_userok(char *user)
1036 {
1037 	Buffer m;
1038 	int authenticated = 0;
1039 
1040 	buffer_init(&m);
1041 
1042 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSUSEROK, &m);
1043 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSUSEROK,
1044 				  &m);
1045 
1046 	authenticated = buffer_get_int(&m);
1047 
1048 	buffer_free(&m);
1049 	debug3("%s: user %sauthenticated",__func__, authenticated ? "" : "not ");
1050 	return (authenticated);
1051 }
1052 #endif /* GSSAPI */
1053