xref: /freebsd/crypto/openssh/monitor_wrap.c (revision 87569f75a91f298c52a71823c04d41cf53c88889)
1 /*
2  * Copyright 2002 Niels Provos <provos@citi.umich.edu>
3  * Copyright 2002 Markus Friedl <markus@openbsd.org>
4  * All rights reserved.
5  *
6  * Redistribution and use in source and binary forms, with or without
7  * modification, are permitted provided that the following conditions
8  * are met:
9  * 1. Redistributions of source code must retain the above copyright
10  *    notice, this list of conditions and the following disclaimer.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  *
15  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25  */
26 
27 #include "includes.h"
28 RCSID("$OpenBSD: monitor_wrap.c,v 1.40 2005/05/24 17:32:43 avsm Exp $");
29 RCSID("$FreeBSD$");
30 
31 #include <openssl/bn.h>
32 #include <openssl/dh.h>
33 
34 #include "ssh.h"
35 #include "dh.h"
36 #include "kex.h"
37 #include "auth.h"
38 #include "auth-options.h"
39 #include "buffer.h"
40 #include "bufaux.h"
41 #include "packet.h"
42 #include "mac.h"
43 #include "log.h"
44 #ifdef TARGET_OS_MAC    /* XXX Broken krb5 headers on Mac */
45 #undef TARGET_OS_MAC
46 #include "zlib.h"
47 #define TARGET_OS_MAC 1
48 #else
49 #include "zlib.h"
50 #endif
51 #include "monitor.h"
52 #include "monitor_wrap.h"
53 #include "xmalloc.h"
54 #include "atomicio.h"
55 #include "monitor_fdpass.h"
56 #include "getput.h"
57 #include "servconf.h"
58 
59 #include "auth.h"
60 #include "channels.h"
61 #include "session.h"
62 
63 #ifdef GSSAPI
64 #include "ssh-gss.h"
65 #endif
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 extern ServerOptions options;
76 extern Buffer loginmsg;
77 
78 int
79 mm_is_monitor(void)
80 {
81 	/*
82 	 * m_pid is only set in the privileged part, and
83 	 * points to the unprivileged child.
84 	 */
85 	return (pmonitor && pmonitor->m_pid > 0);
86 }
87 
88 void
89 mm_request_send(int sock, enum monitor_reqtype type, Buffer *m)
90 {
91 	u_int mlen = buffer_len(m);
92 	u_char buf[5];
93 
94 	debug3("%s entering: type %d", __func__, type);
95 
96 	PUT_32BIT(buf, mlen + 1);
97 	buf[4] = (u_char) type;		/* 1st byte of payload is mesg-type */
98 	if (atomicio(vwrite, sock, buf, sizeof(buf)) != sizeof(buf))
99 		fatal("%s: write: %s", __func__, strerror(errno));
100 	if (atomicio(vwrite, sock, buffer_ptr(m), mlen) != mlen)
101 		fatal("%s: write: %s", __func__, strerror(errno));
102 }
103 
104 void
105 mm_request_receive(int sock, Buffer *m)
106 {
107 	u_char buf[4];
108 	u_int msg_len;
109 
110 	debug3("%s entering", __func__);
111 
112 	if (atomicio(read, sock, buf, sizeof(buf)) != sizeof(buf)) {
113 		if (errno == EPIPE)
114 			cleanup_exit(255);
115 		fatal("%s: read: %s", __func__, strerror(errno));
116 	}
117 	msg_len = GET_32BIT(buf);
118 	if (msg_len > 256 * 1024)
119 		fatal("%s: read: bad msg_len %d", __func__, msg_len);
120 	buffer_clear(m);
121 	buffer_append_space(m, msg_len);
122 	if (atomicio(read, sock, buffer_ptr(m), msg_len) != msg_len)
123 		fatal("%s: read: %s", __func__, strerror(errno));
124 }
125 
126 void
127 mm_request_receive_expect(int sock, enum monitor_reqtype type, Buffer *m)
128 {
129 	u_char rtype;
130 
131 	debug3("%s entering: type %d", __func__, type);
132 
133 	mm_request_receive(sock, m);
134 	rtype = buffer_get_char(m);
135 	if (rtype != type)
136 		fatal("%s: read: rtype %d != type %d", __func__,
137 		    rtype, type);
138 }
139 
140 DH *
141 mm_choose_dh(int min, int nbits, int max)
142 {
143 	BIGNUM *p, *g;
144 	int success = 0;
145 	Buffer m;
146 
147 	buffer_init(&m);
148 	buffer_put_int(&m, min);
149 	buffer_put_int(&m, nbits);
150 	buffer_put_int(&m, max);
151 
152 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_MODULI, &m);
153 
154 	debug3("%s: waiting for MONITOR_ANS_MODULI", __func__);
155 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_MODULI, &m);
156 
157 	success = buffer_get_char(&m);
158 	if (success == 0)
159 		fatal("%s: MONITOR_ANS_MODULI failed", __func__);
160 
161 	if ((p = BN_new()) == NULL)
162 		fatal("%s: BN_new failed", __func__);
163 	if ((g = BN_new()) == NULL)
164 		fatal("%s: BN_new failed", __func__);
165 	buffer_get_bignum2(&m, p);
166 	buffer_get_bignum2(&m, g);
167 
168 	debug3("%s: remaining %d", __func__, buffer_len(&m));
169 	buffer_free(&m);
170 
171 	return (dh_new_group(g, p));
172 }
173 
174 int
175 mm_key_sign(Key *key, u_char **sigp, u_int *lenp, u_char *data, u_int datalen)
176 {
177 	Kex *kex = *pmonitor->m_pkex;
178 	Buffer m;
179 
180 	debug3("%s entering", __func__);
181 
182 	buffer_init(&m);
183 	buffer_put_int(&m, kex->host_key_index(key));
184 	buffer_put_string(&m, data, datalen);
185 
186 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SIGN, &m);
187 
188 	debug3("%s: waiting for MONITOR_ANS_SIGN", __func__);
189 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SIGN, &m);
190 	*sigp  = buffer_get_string(&m, lenp);
191 	buffer_free(&m);
192 
193 	return (0);
194 }
195 
196 struct passwd *
197 mm_getpwnamallow(const char *username)
198 {
199 	Buffer m;
200 	struct passwd *pw;
201 	u_int pwlen;
202 
203 	debug3("%s entering", __func__);
204 
205 	buffer_init(&m);
206 	buffer_put_cstring(&m, username);
207 
208 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PWNAM, &m);
209 
210 	debug3("%s: waiting for MONITOR_ANS_PWNAM", __func__);
211 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PWNAM, &m);
212 
213 	if (buffer_get_char(&m) == 0) {
214 		buffer_free(&m);
215 		return (NULL);
216 	}
217 	pw = buffer_get_string(&m, &pwlen);
218 	if (pwlen != sizeof(struct passwd))
219 		fatal("%s: struct passwd size mismatch", __func__);
220 	pw->pw_name = buffer_get_string(&m, NULL);
221 	pw->pw_passwd = buffer_get_string(&m, NULL);
222 	pw->pw_gecos = buffer_get_string(&m, NULL);
223 #ifdef HAVE_PW_CLASS_IN_PASSWD
224 	pw->pw_class = buffer_get_string(&m, NULL);
225 #endif
226 	pw->pw_dir = buffer_get_string(&m, NULL);
227 	pw->pw_shell = buffer_get_string(&m, NULL);
228 	buffer_free(&m);
229 
230 	return (pw);
231 }
232 
233 char *
234 mm_auth2_read_banner(void)
235 {
236 	Buffer m;
237 	char *banner;
238 
239 	debug3("%s entering", __func__);
240 
241 	buffer_init(&m);
242 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTH2_READ_BANNER, &m);
243 	buffer_clear(&m);
244 
245 	mm_request_receive_expect(pmonitor->m_recvfd,
246 	    MONITOR_ANS_AUTH2_READ_BANNER, &m);
247 	banner = buffer_get_string(&m, NULL);
248 	buffer_free(&m);
249 
250 	/* treat empty banner as missing banner */
251 	if (strlen(banner) == 0) {
252 		xfree(banner);
253 		banner = NULL;
254 	}
255 	return (banner);
256 }
257 
258 /* Inform the privileged process about service and style */
259 
260 void
261 mm_inform_authserv(char *service, char *style)
262 {
263 	Buffer m;
264 
265 	debug3("%s entering", __func__);
266 
267 	buffer_init(&m);
268 	buffer_put_cstring(&m, service);
269 	buffer_put_cstring(&m, style ? style : "");
270 
271 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHSERV, &m);
272 
273 	buffer_free(&m);
274 }
275 
276 /* Do the password authentication */
277 int
278 mm_auth_password(Authctxt *authctxt, char *password)
279 {
280 	Buffer m;
281 	int authenticated = 0;
282 
283 	debug3("%s entering", __func__);
284 
285 	buffer_init(&m);
286 	buffer_put_cstring(&m, password);
287 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHPASSWORD, &m);
288 
289 	debug3("%s: waiting for MONITOR_ANS_AUTHPASSWORD", __func__);
290 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_AUTHPASSWORD, &m);
291 
292 	authenticated = buffer_get_int(&m);
293 
294 	buffer_free(&m);
295 
296 	debug3("%s: user %sauthenticated",
297 	    __func__, authenticated ? "" : "not ");
298 	return (authenticated);
299 }
300 
301 int
302 mm_user_key_allowed(struct passwd *pw, Key *key)
303 {
304 	return (mm_key_allowed(MM_USERKEY, NULL, NULL, key));
305 }
306 
307 int
308 mm_hostbased_key_allowed(struct passwd *pw, char *user, char *host,
309     Key *key)
310 {
311 	return (mm_key_allowed(MM_HOSTKEY, user, host, key));
312 }
313 
314 int
315 mm_auth_rhosts_rsa_key_allowed(struct passwd *pw, char *user,
316     char *host, Key *key)
317 {
318 	int ret;
319 
320 	key->type = KEY_RSA; /* XXX hack for key_to_blob */
321 	ret = mm_key_allowed(MM_RSAHOSTKEY, user, host, key);
322 	key->type = KEY_RSA1;
323 	return (ret);
324 }
325 
326 static void
327 mm_send_debug(Buffer *m)
328 {
329 	char *msg;
330 
331 	while (buffer_len(m)) {
332 		msg = buffer_get_string(m, NULL);
333 		debug3("%s: Sending debug: %s", __func__, msg);
334 		packet_send_debug("%s", msg);
335 		xfree(msg);
336 	}
337 }
338 
339 int
340 mm_key_allowed(enum mm_keytype type, char *user, char *host, Key *key)
341 {
342 	Buffer m;
343 	u_char *blob;
344 	u_int len;
345 	int allowed = 0, have_forced = 0;
346 
347 	debug3("%s entering", __func__);
348 
349 	/* Convert the key to a blob and the pass it over */
350 	if (!key_to_blob(key, &blob, &len))
351 		return (0);
352 
353 	buffer_init(&m);
354 	buffer_put_int(&m, type);
355 	buffer_put_cstring(&m, user ? user : "");
356 	buffer_put_cstring(&m, host ? host : "");
357 	buffer_put_string(&m, blob, len);
358 	xfree(blob);
359 
360 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYALLOWED, &m);
361 
362 	debug3("%s: waiting for MONITOR_ANS_KEYALLOWED", __func__);
363 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_KEYALLOWED, &m);
364 
365 	allowed = buffer_get_int(&m);
366 
367 	/* fake forced command */
368 	auth_clear_options();
369 	have_forced = buffer_get_int(&m);
370 	forced_command = have_forced ? xstrdup("true") : NULL;
371 
372 	/* Send potential debug messages */
373 	mm_send_debug(&m);
374 
375 	buffer_free(&m);
376 
377 	return (allowed);
378 }
379 
380 /*
381  * This key verify needs to send the key type along, because the
382  * privileged parent makes the decision if the key is allowed
383  * for authentication.
384  */
385 
386 int
387 mm_key_verify(Key *key, u_char *sig, u_int siglen, u_char *data, u_int datalen)
388 {
389 	Buffer m;
390 	u_char *blob;
391 	u_int len;
392 	int verified = 0;
393 
394 	debug3("%s entering", __func__);
395 
396 	/* Convert the key to a blob and the pass it over */
397 	if (!key_to_blob(key, &blob, &len))
398 		return (0);
399 
400 	buffer_init(&m);
401 	buffer_put_string(&m, blob, len);
402 	buffer_put_string(&m, sig, siglen);
403 	buffer_put_string(&m, data, datalen);
404 	xfree(blob);
405 
406 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYVERIFY, &m);
407 
408 	debug3("%s: waiting for MONITOR_ANS_KEYVERIFY", __func__);
409 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_KEYVERIFY, &m);
410 
411 	verified = buffer_get_int(&m);
412 
413 	buffer_free(&m);
414 
415 	return (verified);
416 }
417 
418 /* Export key state after authentication */
419 Newkeys *
420 mm_newkeys_from_blob(u_char *blob, int blen)
421 {
422 	Buffer b;
423 	u_int len;
424 	Newkeys *newkey = NULL;
425 	Enc *enc;
426 	Mac *mac;
427 	Comp *comp;
428 
429 	debug3("%s: %p(%d)", __func__, blob, blen);
430 #ifdef DEBUG_PK
431 	dump_base64(stderr, blob, blen);
432 #endif
433 	buffer_init(&b);
434 	buffer_append(&b, blob, blen);
435 
436 	newkey = xmalloc(sizeof(*newkey));
437 	enc = &newkey->enc;
438 	mac = &newkey->mac;
439 	comp = &newkey->comp;
440 
441 	/* Enc structure */
442 	enc->name = buffer_get_string(&b, NULL);
443 	buffer_get(&b, &enc->cipher, sizeof(enc->cipher));
444 	enc->enabled = buffer_get_int(&b);
445 	enc->block_size = buffer_get_int(&b);
446 	enc->key = buffer_get_string(&b, &enc->key_len);
447 	enc->iv = buffer_get_string(&b, &len);
448 	if (len != enc->block_size)
449 		fatal("%s: bad ivlen: expected %u != %u", __func__,
450 		    enc->block_size, len);
451 
452 	if (enc->name == NULL || cipher_by_name(enc->name) != enc->cipher)
453 		fatal("%s: bad cipher name %s or pointer %p", __func__,
454 		    enc->name, enc->cipher);
455 
456 	/* Mac structure */
457 	mac->name = buffer_get_string(&b, NULL);
458 	if (mac->name == NULL || mac_init(mac, mac->name) == -1)
459 		fatal("%s: can not init mac %s", __func__, mac->name);
460 	mac->enabled = buffer_get_int(&b);
461 	mac->key = buffer_get_string(&b, &len);
462 	if (len > mac->key_len)
463 		fatal("%s: bad mac key length: %u > %d", __func__, len,
464 		    mac->key_len);
465 	mac->key_len = len;
466 
467 	/* Comp structure */
468 	comp->type = buffer_get_int(&b);
469 	comp->enabled = buffer_get_int(&b);
470 	comp->name = buffer_get_string(&b, NULL);
471 
472 	len = buffer_len(&b);
473 	if (len != 0)
474 		error("newkeys_from_blob: remaining bytes in blob %u", len);
475 	buffer_free(&b);
476 	return (newkey);
477 }
478 
479 int
480 mm_newkeys_to_blob(int mode, u_char **blobp, u_int *lenp)
481 {
482 	Buffer b;
483 	int len;
484 	Enc *enc;
485 	Mac *mac;
486 	Comp *comp;
487 	Newkeys *newkey = newkeys[mode];
488 
489 	debug3("%s: converting %p", __func__, newkey);
490 
491 	if (newkey == NULL) {
492 		error("%s: newkey == NULL", __func__);
493 		return 0;
494 	}
495 	enc = &newkey->enc;
496 	mac = &newkey->mac;
497 	comp = &newkey->comp;
498 
499 	buffer_init(&b);
500 	/* Enc structure */
501 	buffer_put_cstring(&b, enc->name);
502 	/* The cipher struct is constant and shared, you export pointer */
503 	buffer_append(&b, &enc->cipher, sizeof(enc->cipher));
504 	buffer_put_int(&b, enc->enabled);
505 	buffer_put_int(&b, enc->block_size);
506 	buffer_put_string(&b, enc->key, enc->key_len);
507 	packet_get_keyiv(mode, enc->iv, enc->block_size);
508 	buffer_put_string(&b, enc->iv, enc->block_size);
509 
510 	/* Mac structure */
511 	buffer_put_cstring(&b, mac->name);
512 	buffer_put_int(&b, mac->enabled);
513 	buffer_put_string(&b, mac->key, mac->key_len);
514 
515 	/* Comp structure */
516 	buffer_put_int(&b, comp->type);
517 	buffer_put_int(&b, comp->enabled);
518 	buffer_put_cstring(&b, comp->name);
519 
520 	len = buffer_len(&b);
521 	if (lenp != NULL)
522 		*lenp = len;
523 	if (blobp != NULL) {
524 		*blobp = xmalloc(len);
525 		memcpy(*blobp, buffer_ptr(&b), len);
526 	}
527 	memset(buffer_ptr(&b), 0, len);
528 	buffer_free(&b);
529 	return len;
530 }
531 
532 static void
533 mm_send_kex(Buffer *m, Kex *kex)
534 {
535 	buffer_put_string(m, kex->session_id, kex->session_id_len);
536 	buffer_put_int(m, kex->we_need);
537 	buffer_put_int(m, kex->hostkey_type);
538 	buffer_put_int(m, kex->kex_type);
539 	buffer_put_string(m, buffer_ptr(&kex->my), buffer_len(&kex->my));
540 	buffer_put_string(m, buffer_ptr(&kex->peer), buffer_len(&kex->peer));
541 	buffer_put_int(m, kex->flags);
542 	buffer_put_cstring(m, kex->client_version_string);
543 	buffer_put_cstring(m, kex->server_version_string);
544 }
545 
546 void
547 mm_send_keystate(struct monitor *monitor)
548 {
549 	Buffer m;
550 	u_char *blob, *p;
551 	u_int bloblen, plen;
552 	u_int32_t seqnr, packets;
553 	u_int64_t blocks;
554 
555 	buffer_init(&m);
556 
557 	if (!compat20) {
558 		u_char iv[24];
559 		u_char *key;
560 		u_int ivlen, keylen;
561 
562 		buffer_put_int(&m, packet_get_protocol_flags());
563 
564 		buffer_put_int(&m, packet_get_ssh1_cipher());
565 
566 		debug3("%s: Sending ssh1 KEY+IV", __func__);
567 		keylen = packet_get_encryption_key(NULL);
568 		key = xmalloc(keylen+1);	/* add 1 if keylen == 0 */
569 		keylen = packet_get_encryption_key(key);
570 		buffer_put_string(&m, key, keylen);
571 		memset(key, 0, keylen);
572 		xfree(key);
573 
574 		ivlen = packet_get_keyiv_len(MODE_OUT);
575 		packet_get_keyiv(MODE_OUT, iv, ivlen);
576 		buffer_put_string(&m, iv, ivlen);
577 		ivlen = packet_get_keyiv_len(MODE_OUT);
578 		packet_get_keyiv(MODE_IN, iv, ivlen);
579 		buffer_put_string(&m, iv, ivlen);
580 		goto skip;
581 	} else {
582 		/* Kex for rekeying */
583 		mm_send_kex(&m, *monitor->m_pkex);
584 	}
585 
586 	debug3("%s: Sending new keys: %p %p",
587 	    __func__, newkeys[MODE_OUT], newkeys[MODE_IN]);
588 
589 	/* Keys from Kex */
590 	if (!mm_newkeys_to_blob(MODE_OUT, &blob, &bloblen))
591 		fatal("%s: conversion of newkeys failed", __func__);
592 
593 	buffer_put_string(&m, blob, bloblen);
594 	xfree(blob);
595 
596 	if (!mm_newkeys_to_blob(MODE_IN, &blob, &bloblen))
597 		fatal("%s: conversion of newkeys failed", __func__);
598 
599 	buffer_put_string(&m, blob, bloblen);
600 	xfree(blob);
601 
602 	packet_get_state(MODE_OUT, &seqnr, &blocks, &packets);
603 	buffer_put_int(&m, seqnr);
604 	buffer_put_int64(&m, blocks);
605 	buffer_put_int(&m, packets);
606 	packet_get_state(MODE_IN, &seqnr, &blocks, &packets);
607 	buffer_put_int(&m, seqnr);
608 	buffer_put_int64(&m, blocks);
609 	buffer_put_int(&m, packets);
610 
611 	debug3("%s: New keys have been sent", __func__);
612  skip:
613 	/* More key context */
614 	plen = packet_get_keycontext(MODE_OUT, NULL);
615 	p = xmalloc(plen+1);
616 	packet_get_keycontext(MODE_OUT, p);
617 	buffer_put_string(&m, p, plen);
618 	xfree(p);
619 
620 	plen = packet_get_keycontext(MODE_IN, NULL);
621 	p = xmalloc(plen+1);
622 	packet_get_keycontext(MODE_IN, p);
623 	buffer_put_string(&m, p, plen);
624 	xfree(p);
625 
626 	/* Compression state */
627 	debug3("%s: Sending compression state", __func__);
628 	buffer_put_string(&m, &outgoing_stream, sizeof(outgoing_stream));
629 	buffer_put_string(&m, &incoming_stream, sizeof(incoming_stream));
630 
631 	/* Network I/O buffers */
632 	buffer_put_string(&m, buffer_ptr(&input), buffer_len(&input));
633 	buffer_put_string(&m, buffer_ptr(&output), buffer_len(&output));
634 
635 	mm_request_send(monitor->m_recvfd, MONITOR_REQ_KEYEXPORT, &m);
636 	debug3("%s: Finished sending state", __func__);
637 
638 	buffer_free(&m);
639 }
640 
641 int
642 mm_pty_allocate(int *ptyfd, int *ttyfd, char *namebuf, int namebuflen)
643 {
644 	Buffer m;
645 	char *p, *msg;
646 	int success = 0;
647 
648 	buffer_init(&m);
649 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTY, &m);
650 
651 	debug3("%s: waiting for MONITOR_ANS_PTY", __func__);
652 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PTY, &m);
653 
654 	success = buffer_get_int(&m);
655 	if (success == 0) {
656 		debug3("%s: pty alloc failed", __func__);
657 		buffer_free(&m);
658 		return (0);
659 	}
660 	p = buffer_get_string(&m, NULL);
661 	msg = buffer_get_string(&m, NULL);
662 	buffer_free(&m);
663 
664 	strlcpy(namebuf, p, namebuflen); /* Possible truncation */
665 	xfree(p);
666 
667 	buffer_append(&loginmsg, msg, strlen(msg));
668 	xfree(msg);
669 
670 	*ptyfd = mm_receive_fd(pmonitor->m_recvfd);
671 	*ttyfd = mm_receive_fd(pmonitor->m_recvfd);
672 
673 	/* Success */
674 	return (1);
675 }
676 
677 void
678 mm_session_pty_cleanup2(Session *s)
679 {
680 	Buffer m;
681 
682 	if (s->ttyfd == -1)
683 		return;
684 	buffer_init(&m);
685 	buffer_put_cstring(&m, s->tty);
686 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTYCLEANUP, &m);
687 	buffer_free(&m);
688 
689 	/* closed dup'ed master */
690 	if (close(s->ptymaster) < 0)
691 		error("close(s->ptymaster): %s", strerror(errno));
692 
693 	/* unlink pty from session */
694 	s->ttyfd = -1;
695 }
696 
697 #ifdef USE_PAM
698 void
699 mm_start_pam(Authctxt *authctxt)
700 {
701 	Buffer m;
702 
703 	debug3("%s entering", __func__);
704 	if (!options.use_pam)
705 		fatal("UsePAM=no, but ended up in %s anyway", __func__);
706 
707 	buffer_init(&m);
708 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_START, &m);
709 
710 	buffer_free(&m);
711 }
712 
713 u_int
714 mm_do_pam_account(void)
715 {
716 	Buffer m;
717 	u_int ret;
718 	char *msg;
719 
720 	debug3("%s entering", __func__);
721 	if (!options.use_pam)
722 		fatal("UsePAM=no, but ended up in %s anyway", __func__);
723 
724 	buffer_init(&m);
725 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_ACCOUNT, &m);
726 
727 	mm_request_receive_expect(pmonitor->m_recvfd,
728 	    MONITOR_ANS_PAM_ACCOUNT, &m);
729 	ret = buffer_get_int(&m);
730 	msg = buffer_get_string(&m, NULL);
731 	buffer_append(&loginmsg, msg, strlen(msg));
732 	xfree(msg);
733 
734 	buffer_free(&m);
735 
736 	debug3("%s returning %d", __func__, ret);
737 
738 	return (ret);
739 }
740 
741 void *
742 mm_sshpam_init_ctx(Authctxt *authctxt)
743 {
744 	Buffer m;
745 	int success;
746 
747 	debug3("%s", __func__);
748 	buffer_init(&m);
749 	buffer_put_cstring(&m, authctxt->user);
750 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_INIT_CTX, &m);
751 	debug3("%s: waiting for MONITOR_ANS_PAM_INIT_CTX", __func__);
752 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_INIT_CTX, &m);
753 	success = buffer_get_int(&m);
754 	if (success == 0) {
755 		debug3("%s: pam_init_ctx failed", __func__);
756 		buffer_free(&m);
757 		return (NULL);
758 	}
759 	buffer_free(&m);
760 	return (authctxt);
761 }
762 
763 int
764 mm_sshpam_query(void *ctx, char **name, char **info,
765     u_int *num, char ***prompts, u_int **echo_on)
766 {
767 	Buffer m;
768 	u_int i;
769 	int ret;
770 
771 	debug3("%s", __func__);
772 	buffer_init(&m);
773 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_QUERY, &m);
774 	debug3("%s: waiting for MONITOR_ANS_PAM_QUERY", __func__);
775 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_QUERY, &m);
776 	ret = buffer_get_int(&m);
777 	debug3("%s: pam_query returned %d", __func__, ret);
778 	*name = buffer_get_string(&m, NULL);
779 	*info = buffer_get_string(&m, NULL);
780 	*num = buffer_get_int(&m);
781 	*prompts = xmalloc((*num + 1) * sizeof(char *));
782 	*echo_on = xmalloc((*num + 1) * sizeof(u_int));
783 	for (i = 0; i < *num; ++i) {
784 		(*prompts)[i] = buffer_get_string(&m, NULL);
785 		(*echo_on)[i] = buffer_get_int(&m);
786 	}
787 	buffer_free(&m);
788 	return (ret);
789 }
790 
791 int
792 mm_sshpam_respond(void *ctx, u_int num, char **resp)
793 {
794 	Buffer m;
795 	u_int i;
796 	int ret;
797 
798 	debug3("%s", __func__);
799 	buffer_init(&m);
800 	buffer_put_int(&m, num);
801 	for (i = 0; i < num; ++i)
802 		buffer_put_cstring(&m, resp[i]);
803 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_RESPOND, &m);
804 	debug3("%s: waiting for MONITOR_ANS_PAM_RESPOND", __func__);
805 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_RESPOND, &m);
806 	ret = buffer_get_int(&m);
807 	debug3("%s: pam_respond returned %d", __func__, ret);
808 	buffer_free(&m);
809 	return (ret);
810 }
811 
812 void
813 mm_sshpam_free_ctx(void *ctxtp)
814 {
815 	Buffer m;
816 
817 	debug3("%s", __func__);
818 	buffer_init(&m);
819 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_FREE_CTX, &m);
820 	debug3("%s: waiting for MONITOR_ANS_PAM_FREE_CTX", __func__);
821 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_FREE_CTX, &m);
822 	buffer_free(&m);
823 }
824 #endif /* USE_PAM */
825 
826 /* Request process termination */
827 
828 void
829 mm_terminate(void)
830 {
831 	Buffer m;
832 
833 	buffer_init(&m);
834 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_TERM, &m);
835 	buffer_free(&m);
836 }
837 
838 int
839 mm_ssh1_session_key(BIGNUM *num)
840 {
841 	int rsafail;
842 	Buffer m;
843 
844 	buffer_init(&m);
845 	buffer_put_bignum2(&m, num);
846 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SESSKEY, &m);
847 
848 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SESSKEY, &m);
849 
850 	rsafail = buffer_get_int(&m);
851 	buffer_get_bignum2(&m, num);
852 
853 	buffer_free(&m);
854 
855 	return (rsafail);
856 }
857 
858 static void
859 mm_chall_setup(char **name, char **infotxt, u_int *numprompts,
860     char ***prompts, u_int **echo_on)
861 {
862 	*name = xstrdup("");
863 	*infotxt = xstrdup("");
864 	*numprompts = 1;
865 	*prompts = xmalloc(*numprompts * sizeof(char *));
866 	*echo_on = xmalloc(*numprompts * sizeof(u_int));
867 	(*echo_on)[0] = 0;
868 }
869 
870 int
871 mm_bsdauth_query(void *ctx, char **name, char **infotxt,
872    u_int *numprompts, char ***prompts, u_int **echo_on)
873 {
874 	Buffer m;
875 	u_int success;
876 	char *challenge;
877 
878 	debug3("%s: entering", __func__);
879 
880 	buffer_init(&m);
881 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHQUERY, &m);
882 
883 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_BSDAUTHQUERY,
884 	    &m);
885 	success = buffer_get_int(&m);
886 	if (success == 0) {
887 		debug3("%s: no challenge", __func__);
888 		buffer_free(&m);
889 		return (-1);
890 	}
891 
892 	/* Get the challenge, and format the response */
893 	challenge  = buffer_get_string(&m, NULL);
894 	buffer_free(&m);
895 
896 	mm_chall_setup(name, infotxt, numprompts, prompts, echo_on);
897 	(*prompts)[0] = challenge;
898 
899 	debug3("%s: received challenge: %s", __func__, challenge);
900 
901 	return (0);
902 }
903 
904 int
905 mm_bsdauth_respond(void *ctx, u_int numresponses, char **responses)
906 {
907 	Buffer m;
908 	int authok;
909 
910 	debug3("%s: entering", __func__);
911 	if (numresponses != 1)
912 		return (-1);
913 
914 	buffer_init(&m);
915 	buffer_put_cstring(&m, responses[0]);
916 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHRESPOND, &m);
917 
918 	mm_request_receive_expect(pmonitor->m_recvfd,
919 	    MONITOR_ANS_BSDAUTHRESPOND, &m);
920 
921 	authok = buffer_get_int(&m);
922 	buffer_free(&m);
923 
924 	return ((authok == 0) ? -1 : 0);
925 }
926 
927 #ifdef SKEY
928 int
929 mm_skey_query(void *ctx, char **name, char **infotxt,
930    u_int *numprompts, char ***prompts, u_int **echo_on)
931 {
932 	Buffer m;
933 	int len;
934 	u_int success;
935 	char *p, *challenge;
936 
937 	debug3("%s: entering", __func__);
938 
939 	buffer_init(&m);
940 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SKEYQUERY, &m);
941 
942 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SKEYQUERY,
943 	    &m);
944 	success = buffer_get_int(&m);
945 	if (success == 0) {
946 		debug3("%s: no challenge", __func__);
947 		buffer_free(&m);
948 		return (-1);
949 	}
950 
951 	/* Get the challenge, and format the response */
952 	challenge  = buffer_get_string(&m, NULL);
953 	buffer_free(&m);
954 
955 	debug3("%s: received challenge: %s", __func__, challenge);
956 
957 	mm_chall_setup(name, infotxt, numprompts, prompts, echo_on);
958 
959 	len = strlen(challenge) + strlen(SKEY_PROMPT) + 1;
960 	p = xmalloc(len);
961 	strlcpy(p, challenge, len);
962 	strlcat(p, SKEY_PROMPT, len);
963 	(*prompts)[0] = p;
964 	xfree(challenge);
965 
966 	return (0);
967 }
968 
969 int
970 mm_skey_respond(void *ctx, u_int numresponses, char **responses)
971 {
972 	Buffer m;
973 	int authok;
974 
975 	debug3("%s: entering", __func__);
976 	if (numresponses != 1)
977 		return (-1);
978 
979 	buffer_init(&m);
980 	buffer_put_cstring(&m, responses[0]);
981 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SKEYRESPOND, &m);
982 
983 	mm_request_receive_expect(pmonitor->m_recvfd,
984 	    MONITOR_ANS_SKEYRESPOND, &m);
985 
986 	authok = buffer_get_int(&m);
987 	buffer_free(&m);
988 
989 	return ((authok == 0) ? -1 : 0);
990 }
991 #endif /* SKEY */
992 
993 void
994 mm_ssh1_session_id(u_char session_id[16])
995 {
996 	Buffer m;
997 	int i;
998 
999 	debug3("%s entering", __func__);
1000 
1001 	buffer_init(&m);
1002 	for (i = 0; i < 16; i++)
1003 		buffer_put_char(&m, session_id[i]);
1004 
1005 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SESSID, &m);
1006 	buffer_free(&m);
1007 }
1008 
1009 int
1010 mm_auth_rsa_key_allowed(struct passwd *pw, BIGNUM *client_n, Key **rkey)
1011 {
1012 	Buffer m;
1013 	Key *key;
1014 	u_char *blob;
1015 	u_int blen;
1016 	int allowed = 0, have_forced = 0;
1017 
1018 	debug3("%s entering", __func__);
1019 
1020 	buffer_init(&m);
1021 	buffer_put_bignum2(&m, client_n);
1022 
1023 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSAKEYALLOWED, &m);
1024 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSAKEYALLOWED, &m);
1025 
1026 	allowed = buffer_get_int(&m);
1027 
1028 	/* fake forced command */
1029 	auth_clear_options();
1030 	have_forced = buffer_get_int(&m);
1031 	forced_command = have_forced ? xstrdup("true") : NULL;
1032 
1033 	if (allowed && rkey != NULL) {
1034 		blob = buffer_get_string(&m, &blen);
1035 		if ((key = key_from_blob(blob, blen)) == NULL)
1036 			fatal("%s: key_from_blob failed", __func__);
1037 		*rkey = key;
1038 		xfree(blob);
1039 	}
1040 	mm_send_debug(&m);
1041 	buffer_free(&m);
1042 
1043 	return (allowed);
1044 }
1045 
1046 BIGNUM *
1047 mm_auth_rsa_generate_challenge(Key *key)
1048 {
1049 	Buffer m;
1050 	BIGNUM *challenge;
1051 	u_char *blob;
1052 	u_int blen;
1053 
1054 	debug3("%s entering", __func__);
1055 
1056 	if ((challenge = BN_new()) == NULL)
1057 		fatal("%s: BN_new failed", __func__);
1058 
1059 	key->type = KEY_RSA;    /* XXX cheat for key_to_blob */
1060 	if (key_to_blob(key, &blob, &blen) == 0)
1061 		fatal("%s: key_to_blob failed", __func__);
1062 	key->type = KEY_RSA1;
1063 
1064 	buffer_init(&m);
1065 	buffer_put_string(&m, blob, blen);
1066 	xfree(blob);
1067 
1068 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSACHALLENGE, &m);
1069 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSACHALLENGE, &m);
1070 
1071 	buffer_get_bignum2(&m, challenge);
1072 	buffer_free(&m);
1073 
1074 	return (challenge);
1075 }
1076 
1077 int
1078 mm_auth_rsa_verify_response(Key *key, BIGNUM *p, u_char response[16])
1079 {
1080 	Buffer m;
1081 	u_char *blob;
1082 	u_int blen;
1083 	int success = 0;
1084 
1085 	debug3("%s entering", __func__);
1086 
1087 	key->type = KEY_RSA;    /* XXX cheat for key_to_blob */
1088 	if (key_to_blob(key, &blob, &blen) == 0)
1089 		fatal("%s: key_to_blob failed", __func__);
1090 	key->type = KEY_RSA1;
1091 
1092 	buffer_init(&m);
1093 	buffer_put_string(&m, blob, blen);
1094 	buffer_put_string(&m, response, 16);
1095 	xfree(blob);
1096 
1097 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSARESPONSE, &m);
1098 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSARESPONSE, &m);
1099 
1100 	success = buffer_get_int(&m);
1101 	buffer_free(&m);
1102 
1103 	return (success);
1104 }
1105 
1106 #ifdef SSH_AUDIT_EVENTS
1107 void
1108 mm_audit_event(ssh_audit_event_t event)
1109 {
1110 	Buffer m;
1111 
1112 	debug3("%s entering", __func__);
1113 
1114 	buffer_init(&m);
1115 	buffer_put_int(&m, event);
1116 
1117 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUDIT_EVENT, &m);
1118 	buffer_free(&m);
1119 }
1120 
1121 void
1122 mm_audit_run_command(const char *command)
1123 {
1124 	Buffer m;
1125 
1126 	debug3("%s entering command %s", __func__, command);
1127 
1128 	buffer_init(&m);
1129 	buffer_put_cstring(&m, command);
1130 
1131 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUDIT_COMMAND, &m);
1132 	buffer_free(&m);
1133 }
1134 #endif /* SSH_AUDIT_EVENTS */
1135 
1136 #ifdef GSSAPI
1137 OM_uint32
1138 mm_ssh_gssapi_server_ctx(Gssctxt **ctx, gss_OID goid)
1139 {
1140 	Buffer m;
1141 	OM_uint32 major;
1142 
1143 	/* Client doesn't get to see the context */
1144 	*ctx = NULL;
1145 
1146 	buffer_init(&m);
1147 	buffer_put_string(&m, goid->elements, goid->length);
1148 
1149 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSETUP, &m);
1150 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSETUP, &m);
1151 
1152 	major = buffer_get_int(&m);
1153 
1154 	buffer_free(&m);
1155 	return (major);
1156 }
1157 
1158 OM_uint32
1159 mm_ssh_gssapi_accept_ctx(Gssctxt *ctx, gss_buffer_desc *in,
1160     gss_buffer_desc *out, OM_uint32 *flags)
1161 {
1162 	Buffer m;
1163 	OM_uint32 major;
1164 	u_int len;
1165 
1166 	buffer_init(&m);
1167 	buffer_put_string(&m, in->value, in->length);
1168 
1169 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSTEP, &m);
1170 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSTEP, &m);
1171 
1172 	major = buffer_get_int(&m);
1173 	out->value = buffer_get_string(&m, &len);
1174 	out->length = len;
1175 	if (flags)
1176 		*flags = buffer_get_int(&m);
1177 
1178 	buffer_free(&m);
1179 
1180 	return (major);
1181 }
1182 
1183 OM_uint32
1184 mm_ssh_gssapi_checkmic(Gssctxt *ctx, gss_buffer_t gssbuf, gss_buffer_t gssmic)
1185 {
1186 	Buffer m;
1187 	OM_uint32 major;
1188 
1189 	buffer_init(&m);
1190 	buffer_put_string(&m, gssbuf->value, gssbuf->length);
1191 	buffer_put_string(&m, gssmic->value, gssmic->length);
1192 
1193 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSCHECKMIC, &m);
1194 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSCHECKMIC,
1195 	    &m);
1196 
1197 	major = buffer_get_int(&m);
1198 	buffer_free(&m);
1199 	return(major);
1200 }
1201 
1202 int
1203 mm_ssh_gssapi_userok(char *user)
1204 {
1205 	Buffer m;
1206 	int authenticated = 0;
1207 
1208 	buffer_init(&m);
1209 
1210 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSUSEROK, &m);
1211 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSUSEROK,
1212 				  &m);
1213 
1214 	authenticated = buffer_get_int(&m);
1215 
1216 	buffer_free(&m);
1217 	debug3("%s: user %sauthenticated",__func__, authenticated ? "" : "not ");
1218 	return (authenticated);
1219 }
1220 #endif /* GSSAPI */
1221