xref: /freebsd/crypto/openssh/monitor_wrap.c (revision 0f8f86b71f022b803e99151c19db81b280f245dc)
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 1.35 2003/11/17 11:06:07 markus 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 #include "zlib.h"
45 #include "monitor.h"
46 #include "monitor_wrap.h"
47 #include "xmalloc.h"
48 #include "atomicio.h"
49 #include "monitor_fdpass.h"
50 #include "getput.h"
51 #include "servconf.h"
52 
53 #include "auth.h"
54 #include "channels.h"
55 #include "session.h"
56 
57 #ifdef GSSAPI
58 #include "ssh-gss.h"
59 #endif
60 
61 /* Imports */
62 extern int compat20;
63 extern Newkeys *newkeys[];
64 extern z_stream incoming_stream;
65 extern z_stream outgoing_stream;
66 extern struct monitor *pmonitor;
67 extern Buffer input, output;
68 extern ServerOptions options;
69 
70 int
71 mm_is_monitor(void)
72 {
73 	/*
74 	 * m_pid is only set in the privileged part, and
75 	 * points to the unprivileged child.
76 	 */
77 	return (pmonitor && pmonitor->m_pid > 0);
78 }
79 
80 void
81 mm_request_send(int socket, enum monitor_reqtype type, Buffer *m)
82 {
83 	u_int mlen = buffer_len(m);
84 	u_char buf[5];
85 
86 	debug3("%s entering: type %d", __func__, type);
87 
88 	PUT_32BIT(buf, mlen + 1);
89 	buf[4] = (u_char) type;		/* 1st byte of payload is mesg-type */
90 	if (atomicio(vwrite, socket, buf, sizeof(buf)) != sizeof(buf))
91 		fatal("%s: write", __func__);
92 	if (atomicio(vwrite, socket, buffer_ptr(m), mlen) != mlen)
93 		fatal("%s: write", __func__);
94 }
95 
96 void
97 mm_request_receive(int socket, Buffer *m)
98 {
99 	u_char buf[4];
100 	u_int msg_len;
101 	ssize_t res;
102 
103 	debug3("%s entering", __func__);
104 
105 	res = atomicio(read, socket, buf, sizeof(buf));
106 	if (res != sizeof(buf)) {
107 		if (res == 0)
108 			cleanup_exit(255);
109 		fatal("%s: read: %ld", __func__, (long)res);
110 	}
111 	msg_len = GET_32BIT(buf);
112 	if (msg_len > 256 * 1024)
113 		fatal("%s: read: bad msg_len %d", __func__, msg_len);
114 	buffer_clear(m);
115 	buffer_append_space(m, msg_len);
116 	res = atomicio(read, socket, buffer_ptr(m), msg_len);
117 	if (res != msg_len)
118 		fatal("%s: read: %ld != msg_len", __func__, (long)res);
119 }
120 
121 void
122 mm_request_receive_expect(int socket, enum monitor_reqtype type, Buffer *m)
123 {
124 	u_char rtype;
125 
126 	debug3("%s entering: type %d", __func__, type);
127 
128 	mm_request_receive(socket, m);
129 	rtype = buffer_get_char(m);
130 	if (rtype != type)
131 		fatal("%s: read: rtype %d != type %d", __func__,
132 		    rtype, type);
133 }
134 
135 DH *
136 mm_choose_dh(int min, int nbits, int max)
137 {
138 	BIGNUM *p, *g;
139 	int success = 0;
140 	Buffer m;
141 
142 	buffer_init(&m);
143 	buffer_put_int(&m, min);
144 	buffer_put_int(&m, nbits);
145 	buffer_put_int(&m, max);
146 
147 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_MODULI, &m);
148 
149 	debug3("%s: waiting for MONITOR_ANS_MODULI", __func__);
150 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_MODULI, &m);
151 
152 	success = buffer_get_char(&m);
153 	if (success == 0)
154 		fatal("%s: MONITOR_ANS_MODULI failed", __func__);
155 
156 	if ((p = BN_new()) == NULL)
157 		fatal("%s: BN_new failed", __func__);
158 	if ((g = BN_new()) == NULL)
159 		fatal("%s: BN_new failed", __func__);
160 	buffer_get_bignum2(&m, p);
161 	buffer_get_bignum2(&m, g);
162 
163 	debug3("%s: remaining %d", __func__, buffer_len(&m));
164 	buffer_free(&m);
165 
166 	return (dh_new_group(g, p));
167 }
168 
169 int
170 mm_key_sign(Key *key, u_char **sigp, u_int *lenp, u_char *data, u_int datalen)
171 {
172 	Kex *kex = *pmonitor->m_pkex;
173 	Buffer m;
174 
175 	debug3("%s entering", __func__);
176 
177 	buffer_init(&m);
178 	buffer_put_int(&m, kex->host_key_index(key));
179 	buffer_put_string(&m, data, datalen);
180 
181 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SIGN, &m);
182 
183 	debug3("%s: waiting for MONITOR_ANS_SIGN", __func__);
184 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SIGN, &m);
185 	*sigp  = buffer_get_string(&m, lenp);
186 	buffer_free(&m);
187 
188 	return (0);
189 }
190 
191 struct passwd *
192 mm_getpwnamallow(const char *login)
193 {
194 	Buffer m;
195 	struct passwd *pw;
196 	u_int pwlen;
197 
198 	debug3("%s entering", __func__);
199 
200 	buffer_init(&m);
201 	buffer_put_cstring(&m, login);
202 
203 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PWNAM, &m);
204 
205 	debug3("%s: waiting for MONITOR_ANS_PWNAM", __func__);
206 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PWNAM, &m);
207 
208 	if (buffer_get_char(&m) == 0) {
209 		buffer_free(&m);
210 		return (NULL);
211 	}
212 	pw = buffer_get_string(&m, &pwlen);
213 	if (pwlen != sizeof(struct passwd))
214 		fatal("%s: struct passwd size mismatch", __func__);
215 	pw->pw_name = buffer_get_string(&m, NULL);
216 	pw->pw_passwd = buffer_get_string(&m, NULL);
217 	pw->pw_gecos = buffer_get_string(&m, NULL);
218 #ifdef HAVE_PW_CLASS_IN_PASSWD
219 	pw->pw_class = buffer_get_string(&m, NULL);
220 #endif
221 	pw->pw_dir = buffer_get_string(&m, NULL);
222 	pw->pw_shell = buffer_get_string(&m, NULL);
223 	buffer_free(&m);
224 
225 	return (pw);
226 }
227 
228 char *
229 mm_auth2_read_banner(void)
230 {
231 	Buffer m;
232 	char *banner;
233 
234 	debug3("%s entering", __func__);
235 
236 	buffer_init(&m);
237 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTH2_READ_BANNER, &m);
238 	buffer_clear(&m);
239 
240 	mm_request_receive_expect(pmonitor->m_recvfd,
241 	    MONITOR_ANS_AUTH2_READ_BANNER, &m);
242 	banner = buffer_get_string(&m, NULL);
243 	buffer_free(&m);
244 
245 	/* treat empty banner as missing banner */
246 	if (strlen(banner) == 0) {
247 		xfree(banner);
248 		banner = NULL;
249 	}
250 	return (banner);
251 }
252 
253 /* Inform the privileged process about service and style */
254 
255 void
256 mm_inform_authserv(char *service, char *style)
257 {
258 	Buffer m;
259 
260 	debug3("%s entering", __func__);
261 
262 	buffer_init(&m);
263 	buffer_put_cstring(&m, service);
264 	buffer_put_cstring(&m, style ? style : "");
265 
266 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHSERV, &m);
267 
268 	buffer_free(&m);
269 }
270 
271 /* Do the password authentication */
272 int
273 mm_auth_password(Authctxt *authctxt, char *password)
274 {
275 	Buffer m;
276 	int authenticated = 0;
277 
278 	debug3("%s entering", __func__);
279 
280 	buffer_init(&m);
281 	buffer_put_cstring(&m, password);
282 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHPASSWORD, &m);
283 
284 	debug3("%s: waiting for MONITOR_ANS_AUTHPASSWORD", __func__);
285 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_AUTHPASSWORD, &m);
286 
287 	authenticated = buffer_get_int(&m);
288 
289 	buffer_free(&m);
290 
291 	debug3("%s: user %sauthenticated",
292 	    __func__, authenticated ? "" : "not ");
293 	return (authenticated);
294 }
295 
296 int
297 mm_user_key_allowed(struct passwd *pw, Key *key)
298 {
299 	return (mm_key_allowed(MM_USERKEY, NULL, NULL, key));
300 }
301 
302 int
303 mm_hostbased_key_allowed(struct passwd *pw, char *user, char *host,
304     Key *key)
305 {
306 	return (mm_key_allowed(MM_HOSTKEY, user, host, key));
307 }
308 
309 int
310 mm_auth_rhosts_rsa_key_allowed(struct passwd *pw, char *user,
311     char *host, Key *key)
312 {
313 	int ret;
314 
315 	key->type = KEY_RSA; /* XXX hack for key_to_blob */
316 	ret = mm_key_allowed(MM_RSAHOSTKEY, user, host, key);
317 	key->type = KEY_RSA1;
318 	return (ret);
319 }
320 
321 static void
322 mm_send_debug(Buffer *m)
323 {
324 	char *msg;
325 
326 	while (buffer_len(m)) {
327 		msg = buffer_get_string(m, NULL);
328 		debug3("%s: Sending debug: %s", __func__, msg);
329 		packet_send_debug("%s", msg);
330 		xfree(msg);
331 	}
332 }
333 
334 int
335 mm_key_allowed(enum mm_keytype type, char *user, char *host, Key *key)
336 {
337 	Buffer m;
338 	u_char *blob;
339 	u_int len;
340 	int allowed = 0, have_forced = 0;
341 
342 	debug3("%s entering", __func__);
343 
344 	/* Convert the key to a blob and the pass it over */
345 	if (!key_to_blob(key, &blob, &len))
346 		return (0);
347 
348 	buffer_init(&m);
349 	buffer_put_int(&m, type);
350 	buffer_put_cstring(&m, user ? user : "");
351 	buffer_put_cstring(&m, host ? host : "");
352 	buffer_put_string(&m, blob, len);
353 	xfree(blob);
354 
355 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYALLOWED, &m);
356 
357 	debug3("%s: waiting for MONITOR_ANS_KEYALLOWED", __func__);
358 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_KEYALLOWED, &m);
359 
360 	allowed = buffer_get_int(&m);
361 
362 	/* fake forced command */
363 	auth_clear_options();
364 	have_forced = buffer_get_int(&m);
365 	forced_command = have_forced ? xstrdup("true") : NULL;
366 
367 	/* Send potential debug messages */
368 	mm_send_debug(&m);
369 
370 	buffer_free(&m);
371 
372 	return (allowed);
373 }
374 
375 /*
376  * This key verify needs to send the key type along, because the
377  * privileged parent makes the decision if the key is allowed
378  * for authentication.
379  */
380 
381 int
382 mm_key_verify(Key *key, u_char *sig, u_int siglen, u_char *data, u_int datalen)
383 {
384 	Buffer m;
385 	u_char *blob;
386 	u_int len;
387 	int verified = 0;
388 
389 	debug3("%s entering", __func__);
390 
391 	/* Convert the key to a blob and the pass it over */
392 	if (!key_to_blob(key, &blob, &len))
393 		return (0);
394 
395 	buffer_init(&m);
396 	buffer_put_string(&m, blob, len);
397 	buffer_put_string(&m, sig, siglen);
398 	buffer_put_string(&m, data, datalen);
399 	xfree(blob);
400 
401 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYVERIFY, &m);
402 
403 	debug3("%s: waiting for MONITOR_ANS_KEYVERIFY", __func__);
404 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_KEYVERIFY, &m);
405 
406 	verified = buffer_get_int(&m);
407 
408 	buffer_free(&m);
409 
410 	return (verified);
411 }
412 
413 /* Export key state after authentication */
414 Newkeys *
415 mm_newkeys_from_blob(u_char *blob, int blen)
416 {
417 	Buffer b;
418 	u_int len;
419 	Newkeys *newkey = NULL;
420 	Enc *enc;
421 	Mac *mac;
422 	Comp *comp;
423 
424 	debug3("%s: %p(%d)", __func__, blob, blen);
425 #ifdef DEBUG_PK
426 	dump_base64(stderr, blob, blen);
427 #endif
428 	buffer_init(&b);
429 	buffer_append(&b, blob, blen);
430 
431 	newkey = xmalloc(sizeof(*newkey));
432 	enc = &newkey->enc;
433 	mac = &newkey->mac;
434 	comp = &newkey->comp;
435 
436 	/* Enc structure */
437 	enc->name = buffer_get_string(&b, NULL);
438 	buffer_get(&b, &enc->cipher, sizeof(enc->cipher));
439 	enc->enabled = buffer_get_int(&b);
440 	enc->block_size = buffer_get_int(&b);
441 	enc->key = buffer_get_string(&b, &enc->key_len);
442 	enc->iv = buffer_get_string(&b, &len);
443 	if (len != enc->block_size)
444 		fatal("%s: bad ivlen: expected %u != %u", __func__,
445 		    enc->block_size, len);
446 
447 	if (enc->name == NULL || cipher_by_name(enc->name) != enc->cipher)
448 		fatal("%s: bad cipher name %s or pointer %p", __func__,
449 		    enc->name, enc->cipher);
450 
451 	/* Mac structure */
452 	mac->name = buffer_get_string(&b, NULL);
453 	if (mac->name == NULL || mac_init(mac, mac->name) == -1)
454 		fatal("%s: can not init mac %s", __func__, mac->name);
455 	mac->enabled = buffer_get_int(&b);
456 	mac->key = buffer_get_string(&b, &len);
457 	if (len > mac->key_len)
458 		fatal("%s: bad mac key length: %u > %d", __func__, len,
459 		    mac->key_len);
460 	mac->key_len = len;
461 
462 	/* Comp structure */
463 	comp->type = buffer_get_int(&b);
464 	comp->enabled = buffer_get_int(&b);
465 	comp->name = buffer_get_string(&b, NULL);
466 
467 	len = buffer_len(&b);
468 	if (len != 0)
469 		error("newkeys_from_blob: remaining bytes in blob %u", len);
470 	buffer_free(&b);
471 	return (newkey);
472 }
473 
474 int
475 mm_newkeys_to_blob(int mode, u_char **blobp, u_int *lenp)
476 {
477 	Buffer b;
478 	int len;
479 	Enc *enc;
480 	Mac *mac;
481 	Comp *comp;
482 	Newkeys *newkey = newkeys[mode];
483 
484 	debug3("%s: converting %p", __func__, newkey);
485 
486 	if (newkey == NULL) {
487 		error("%s: newkey == NULL", __func__);
488 		return 0;
489 	}
490 	enc = &newkey->enc;
491 	mac = &newkey->mac;
492 	comp = &newkey->comp;
493 
494 	buffer_init(&b);
495 	/* Enc structure */
496 	buffer_put_cstring(&b, enc->name);
497 	/* The cipher struct is constant and shared, you export pointer */
498 	buffer_append(&b, &enc->cipher, sizeof(enc->cipher));
499 	buffer_put_int(&b, enc->enabled);
500 	buffer_put_int(&b, enc->block_size);
501 	buffer_put_string(&b, enc->key, enc->key_len);
502 	packet_get_keyiv(mode, enc->iv, enc->block_size);
503 	buffer_put_string(&b, enc->iv, enc->block_size);
504 
505 	/* Mac structure */
506 	buffer_put_cstring(&b, mac->name);
507 	buffer_put_int(&b, mac->enabled);
508 	buffer_put_string(&b, mac->key, mac->key_len);
509 
510 	/* Comp structure */
511 	buffer_put_int(&b, comp->type);
512 	buffer_put_int(&b, comp->enabled);
513 	buffer_put_cstring(&b, comp->name);
514 
515 	len = buffer_len(&b);
516 	if (lenp != NULL)
517 		*lenp = len;
518 	if (blobp != NULL) {
519 		*blobp = xmalloc(len);
520 		memcpy(*blobp, buffer_ptr(&b), len);
521 	}
522 	memset(buffer_ptr(&b), 0, len);
523 	buffer_free(&b);
524 	return len;
525 }
526 
527 static void
528 mm_send_kex(Buffer *m, Kex *kex)
529 {
530 	buffer_put_string(m, kex->session_id, kex->session_id_len);
531 	buffer_put_int(m, kex->we_need);
532 	buffer_put_int(m, kex->hostkey_type);
533 	buffer_put_int(m, kex->kex_type);
534 	buffer_put_string(m, buffer_ptr(&kex->my), buffer_len(&kex->my));
535 	buffer_put_string(m, buffer_ptr(&kex->peer), buffer_len(&kex->peer));
536 	buffer_put_int(m, kex->flags);
537 	buffer_put_cstring(m, kex->client_version_string);
538 	buffer_put_cstring(m, kex->server_version_string);
539 }
540 
541 void
542 mm_send_keystate(struct monitor *pmonitor)
543 {
544 	Buffer m;
545 	u_char *blob, *p;
546 	u_int bloblen, plen;
547 	u_int32_t seqnr, packets;
548 	u_int64_t blocks;
549 
550 	buffer_init(&m);
551 
552 	if (!compat20) {
553 		u_char iv[24];
554 		u_char *key;
555 		u_int ivlen, keylen;
556 
557 		buffer_put_int(&m, packet_get_protocol_flags());
558 
559 		buffer_put_int(&m, packet_get_ssh1_cipher());
560 
561 		debug3("%s: Sending ssh1 KEY+IV", __func__);
562 		keylen = packet_get_encryption_key(NULL);
563 		key = xmalloc(keylen+1);	/* add 1 if keylen == 0 */
564 		keylen = packet_get_encryption_key(key);
565 		buffer_put_string(&m, key, keylen);
566 		memset(key, 0, keylen);
567 		xfree(key);
568 
569 		ivlen = packet_get_keyiv_len(MODE_OUT);
570 		packet_get_keyiv(MODE_OUT, iv, ivlen);
571 		buffer_put_string(&m, iv, ivlen);
572 		ivlen = packet_get_keyiv_len(MODE_OUT);
573 		packet_get_keyiv(MODE_IN, iv, ivlen);
574 		buffer_put_string(&m, iv, ivlen);
575 		goto skip;
576 	} else {
577 		/* Kex for rekeying */
578 		mm_send_kex(&m, *pmonitor->m_pkex);
579 	}
580 
581 	debug3("%s: Sending new keys: %p %p",
582 	    __func__, newkeys[MODE_OUT], newkeys[MODE_IN]);
583 
584 	/* Keys from Kex */
585 	if (!mm_newkeys_to_blob(MODE_OUT, &blob, &bloblen))
586 		fatal("%s: conversion of newkeys failed", __func__);
587 
588 	buffer_put_string(&m, blob, bloblen);
589 	xfree(blob);
590 
591 	if (!mm_newkeys_to_blob(MODE_IN, &blob, &bloblen))
592 		fatal("%s: conversion of newkeys failed", __func__);
593 
594 	buffer_put_string(&m, blob, bloblen);
595 	xfree(blob);
596 
597 	packet_get_state(MODE_OUT, &seqnr, &blocks, &packets);
598 	buffer_put_int(&m, seqnr);
599 	buffer_put_int64(&m, blocks);
600 	buffer_put_int(&m, packets);
601 	packet_get_state(MODE_IN, &seqnr, &blocks, &packets);
602 	buffer_put_int(&m, seqnr);
603 	buffer_put_int64(&m, blocks);
604 	buffer_put_int(&m, packets);
605 
606 	debug3("%s: New keys have been sent", __func__);
607  skip:
608 	/* More key context */
609 	plen = packet_get_keycontext(MODE_OUT, NULL);
610 	p = xmalloc(plen+1);
611 	packet_get_keycontext(MODE_OUT, p);
612 	buffer_put_string(&m, p, plen);
613 	xfree(p);
614 
615 	plen = packet_get_keycontext(MODE_IN, NULL);
616 	p = xmalloc(plen+1);
617 	packet_get_keycontext(MODE_IN, p);
618 	buffer_put_string(&m, p, plen);
619 	xfree(p);
620 
621 	/* Compression state */
622 	debug3("%s: Sending compression state", __func__);
623 	buffer_put_string(&m, &outgoing_stream, sizeof(outgoing_stream));
624 	buffer_put_string(&m, &incoming_stream, sizeof(incoming_stream));
625 
626 	/* Network I/O buffers */
627 	buffer_put_string(&m, buffer_ptr(&input), buffer_len(&input));
628 	buffer_put_string(&m, buffer_ptr(&output), buffer_len(&output));
629 
630 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYEXPORT, &m);
631 	debug3("%s: Finished sending state", __func__);
632 
633 	buffer_free(&m);
634 }
635 
636 int
637 mm_pty_allocate(int *ptyfd, int *ttyfd, char *namebuf, int namebuflen)
638 {
639 	Buffer m;
640 	char *p;
641 	int success = 0;
642 
643 	buffer_init(&m);
644 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTY, &m);
645 
646 	debug3("%s: waiting for MONITOR_ANS_PTY", __func__);
647 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PTY, &m);
648 
649 	success = buffer_get_int(&m);
650 	if (success == 0) {
651 		debug3("%s: pty alloc failed", __func__);
652 		buffer_free(&m);
653 		return (0);
654 	}
655 	p = buffer_get_string(&m, NULL);
656 	buffer_free(&m);
657 
658 	strlcpy(namebuf, p, namebuflen); /* Possible truncation */
659 	xfree(p);
660 
661 	*ptyfd = mm_receive_fd(pmonitor->m_recvfd);
662 	*ttyfd = mm_receive_fd(pmonitor->m_recvfd);
663 
664 	/* Success */
665 	return (1);
666 }
667 
668 void
669 mm_session_pty_cleanup2(Session *s)
670 {
671 	Buffer m;
672 
673 	if (s->ttyfd == -1)
674 		return;
675 	buffer_init(&m);
676 	buffer_put_cstring(&m, s->tty);
677 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTYCLEANUP, &m);
678 	buffer_free(&m);
679 
680 	/* closed dup'ed master */
681 	if (close(s->ptymaster) < 0)
682 		error("close(s->ptymaster): %s", strerror(errno));
683 
684 	/* unlink pty from session */
685 	s->ttyfd = -1;
686 }
687 
688 #ifdef USE_PAM
689 void
690 mm_start_pam(char *user)
691 {
692 	Buffer m;
693 
694 	debug3("%s entering", __func__);
695 	if (!options.use_pam)
696 		fatal("UsePAM=no, but ended up in %s anyway", __func__);
697 
698 	buffer_init(&m);
699 	buffer_put_cstring(&m, user);
700 
701 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_START, &m);
702 
703 	buffer_free(&m);
704 }
705 
706 u_int
707 mm_do_pam_account(void)
708 {
709 	Buffer m;
710 	u_int ret;
711 
712 	debug3("%s entering", __func__);
713 	if (!options.use_pam)
714 		fatal("UsePAM=no, but ended up in %s anyway", __func__);
715 
716 	buffer_init(&m);
717 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_ACCOUNT, &m);
718 
719 	mm_request_receive_expect(pmonitor->m_recvfd,
720 	    MONITOR_ANS_PAM_ACCOUNT, &m);
721 	ret = buffer_get_int(&m);
722 
723 	buffer_free(&m);
724 
725 	debug3("%s returning %d", __func__, ret);
726 
727 	return (ret);
728 }
729 
730 void *
731 mm_sshpam_init_ctx(Authctxt *authctxt)
732 {
733 	Buffer m;
734 	int success;
735 
736 	debug3("%s", __func__);
737 	buffer_init(&m);
738 	buffer_put_cstring(&m, authctxt->user);
739 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_INIT_CTX, &m);
740 	debug3("%s: waiting for MONITOR_ANS_PAM_INIT_CTX", __func__);
741 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_INIT_CTX, &m);
742 	success = buffer_get_int(&m);
743 	if (success == 0) {
744 		debug3("%s: pam_init_ctx failed", __func__);
745 		buffer_free(&m);
746 		return (NULL);
747 	}
748 	buffer_free(&m);
749 	return (authctxt);
750 }
751 
752 int
753 mm_sshpam_query(void *ctx, char **name, char **info,
754     u_int *num, char ***prompts, u_int **echo_on)
755 {
756 	Buffer m;
757 	int i, ret;
758 
759 	debug3("%s", __func__);
760 	buffer_init(&m);
761 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_QUERY, &m);
762 	debug3("%s: waiting for MONITOR_ANS_PAM_QUERY", __func__);
763 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_QUERY, &m);
764 	ret = buffer_get_int(&m);
765 	debug3("%s: pam_query returned %d", __func__, ret);
766 	*name = buffer_get_string(&m, NULL);
767 	*info = buffer_get_string(&m, NULL);
768 	*num = buffer_get_int(&m);
769 	*prompts = xmalloc((*num + 1) * sizeof(char *));
770 	*echo_on = xmalloc((*num + 1) * sizeof(u_int));
771 	for (i = 0; i < *num; ++i) {
772 		(*prompts)[i] = buffer_get_string(&m, NULL);
773 		(*echo_on)[i] = buffer_get_int(&m);
774 	}
775 	buffer_free(&m);
776 	return (ret);
777 }
778 
779 int
780 mm_sshpam_respond(void *ctx, u_int num, char **resp)
781 {
782 	Buffer m;
783 	int i, ret;
784 
785 	debug3("%s", __func__);
786 	buffer_init(&m);
787 	buffer_put_int(&m, num);
788 	for (i = 0; i < num; ++i)
789 		buffer_put_cstring(&m, resp[i]);
790 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_RESPOND, &m);
791 	debug3("%s: waiting for MONITOR_ANS_PAM_RESPOND", __func__);
792 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_RESPOND, &m);
793 	ret = buffer_get_int(&m);
794 	debug3("%s: pam_respond returned %d", __func__, ret);
795 	buffer_free(&m);
796 	return (ret);
797 }
798 
799 void
800 mm_sshpam_free_ctx(void *ctxtp)
801 {
802 	Buffer m;
803 
804 	debug3("%s", __func__);
805 	buffer_init(&m);
806 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_FREE_CTX, &m);
807 	debug3("%s: waiting for MONITOR_ANS_PAM_FREE_CTX", __func__);
808 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_FREE_CTX, &m);
809 	buffer_free(&m);
810 }
811 #endif /* USE_PAM */
812 
813 /* Request process termination */
814 
815 void
816 mm_terminate(void)
817 {
818 	Buffer m;
819 
820 	buffer_init(&m);
821 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_TERM, &m);
822 	buffer_free(&m);
823 }
824 
825 int
826 mm_ssh1_session_key(BIGNUM *num)
827 {
828 	int rsafail;
829 	Buffer m;
830 
831 	buffer_init(&m);
832 	buffer_put_bignum2(&m, num);
833 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SESSKEY, &m);
834 
835 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SESSKEY, &m);
836 
837 	rsafail = buffer_get_int(&m);
838 	buffer_get_bignum2(&m, num);
839 
840 	buffer_free(&m);
841 
842 	return (rsafail);
843 }
844 
845 static void
846 mm_chall_setup(char **name, char **infotxt, u_int *numprompts,
847     char ***prompts, u_int **echo_on)
848 {
849 	*name = xstrdup("");
850 	*infotxt = xstrdup("");
851 	*numprompts = 1;
852 	*prompts = xmalloc(*numprompts * sizeof(char *));
853 	*echo_on = xmalloc(*numprompts * sizeof(u_int));
854 	(*echo_on)[0] = 0;
855 }
856 
857 int
858 mm_bsdauth_query(void *ctx, char **name, char **infotxt,
859    u_int *numprompts, char ***prompts, u_int **echo_on)
860 {
861 	Buffer m;
862 	u_int success;
863 	char *challenge;
864 
865 	debug3("%s: entering", __func__);
866 
867 	buffer_init(&m);
868 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHQUERY, &m);
869 
870 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_BSDAUTHQUERY,
871 	    &m);
872 	success = buffer_get_int(&m);
873 	if (success == 0) {
874 		debug3("%s: no challenge", __func__);
875 		buffer_free(&m);
876 		return (-1);
877 	}
878 
879 	/* Get the challenge, and format the response */
880 	challenge  = buffer_get_string(&m, NULL);
881 	buffer_free(&m);
882 
883 	mm_chall_setup(name, infotxt, numprompts, prompts, echo_on);
884 	(*prompts)[0] = challenge;
885 
886 	debug3("%s: received challenge: %s", __func__, challenge);
887 
888 	return (0);
889 }
890 
891 int
892 mm_bsdauth_respond(void *ctx, u_int numresponses, char **responses)
893 {
894 	Buffer m;
895 	int authok;
896 
897 	debug3("%s: entering", __func__);
898 	if (numresponses != 1)
899 		return (-1);
900 
901 	buffer_init(&m);
902 	buffer_put_cstring(&m, responses[0]);
903 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHRESPOND, &m);
904 
905 	mm_request_receive_expect(pmonitor->m_recvfd,
906 	    MONITOR_ANS_BSDAUTHRESPOND, &m);
907 
908 	authok = buffer_get_int(&m);
909 	buffer_free(&m);
910 
911 	return ((authok == 0) ? -1 : 0);
912 }
913 
914 #ifdef SKEY
915 int
916 mm_skey_query(void *ctx, char **name, char **infotxt,
917    u_int *numprompts, char ***prompts, u_int **echo_on)
918 {
919 	Buffer m;
920 	int len;
921 	u_int success;
922 	char *p, *challenge;
923 
924 	debug3("%s: entering", __func__);
925 
926 	buffer_init(&m);
927 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SKEYQUERY, &m);
928 
929 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SKEYQUERY,
930 	    &m);
931 	success = buffer_get_int(&m);
932 	if (success == 0) {
933 		debug3("%s: no challenge", __func__);
934 		buffer_free(&m);
935 		return (-1);
936 	}
937 
938 	/* Get the challenge, and format the response */
939 	challenge  = buffer_get_string(&m, NULL);
940 	buffer_free(&m);
941 
942 	debug3("%s: received challenge: %s", __func__, challenge);
943 
944 	mm_chall_setup(name, infotxt, numprompts, prompts, echo_on);
945 
946 	len = strlen(challenge) + strlen(SKEY_PROMPT) + 1;
947 	p = xmalloc(len);
948 	strlcpy(p, challenge, len);
949 	strlcat(p, SKEY_PROMPT, len);
950 	(*prompts)[0] = p;
951 	xfree(challenge);
952 
953 	return (0);
954 }
955 
956 int
957 mm_skey_respond(void *ctx, u_int numresponses, char **responses)
958 {
959 	Buffer m;
960 	int authok;
961 
962 	debug3("%s: entering", __func__);
963 	if (numresponses != 1)
964 		return (-1);
965 
966 	buffer_init(&m);
967 	buffer_put_cstring(&m, responses[0]);
968 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SKEYRESPOND, &m);
969 
970 	mm_request_receive_expect(pmonitor->m_recvfd,
971 	    MONITOR_ANS_SKEYRESPOND, &m);
972 
973 	authok = buffer_get_int(&m);
974 	buffer_free(&m);
975 
976 	return ((authok == 0) ? -1 : 0);
977 }
978 #endif
979 
980 void
981 mm_ssh1_session_id(u_char session_id[16])
982 {
983 	Buffer m;
984 	int i;
985 
986 	debug3("%s entering", __func__);
987 
988 	buffer_init(&m);
989 	for (i = 0; i < 16; i++)
990 		buffer_put_char(&m, session_id[i]);
991 
992 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SESSID, &m);
993 	buffer_free(&m);
994 }
995 
996 int
997 mm_auth_rsa_key_allowed(struct passwd *pw, BIGNUM *client_n, Key **rkey)
998 {
999 	Buffer m;
1000 	Key *key;
1001 	u_char *blob;
1002 	u_int blen;
1003 	int allowed = 0, have_forced = 0;
1004 
1005 	debug3("%s entering", __func__);
1006 
1007 	buffer_init(&m);
1008 	buffer_put_bignum2(&m, client_n);
1009 
1010 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSAKEYALLOWED, &m);
1011 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSAKEYALLOWED, &m);
1012 
1013 	allowed = buffer_get_int(&m);
1014 
1015 	/* fake forced command */
1016 	auth_clear_options();
1017 	have_forced = buffer_get_int(&m);
1018 	forced_command = have_forced ? xstrdup("true") : NULL;
1019 
1020 	if (allowed && rkey != NULL) {
1021 		blob = buffer_get_string(&m, &blen);
1022 		if ((key = key_from_blob(blob, blen)) == NULL)
1023 			fatal("%s: key_from_blob failed", __func__);
1024 		*rkey = key;
1025 		xfree(blob);
1026 	}
1027 	mm_send_debug(&m);
1028 	buffer_free(&m);
1029 
1030 	return (allowed);
1031 }
1032 
1033 BIGNUM *
1034 mm_auth_rsa_generate_challenge(Key *key)
1035 {
1036 	Buffer m;
1037 	BIGNUM *challenge;
1038 	u_char *blob;
1039 	u_int blen;
1040 
1041 	debug3("%s entering", __func__);
1042 
1043 	if ((challenge = BN_new()) == NULL)
1044 		fatal("%s: BN_new failed", __func__);
1045 
1046 	key->type = KEY_RSA;    /* XXX cheat for key_to_blob */
1047 	if (key_to_blob(key, &blob, &blen) == 0)
1048 		fatal("%s: key_to_blob failed", __func__);
1049 	key->type = KEY_RSA1;
1050 
1051 	buffer_init(&m);
1052 	buffer_put_string(&m, blob, blen);
1053 	xfree(blob);
1054 
1055 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSACHALLENGE, &m);
1056 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSACHALLENGE, &m);
1057 
1058 	buffer_get_bignum2(&m, challenge);
1059 	buffer_free(&m);
1060 
1061 	return (challenge);
1062 }
1063 
1064 int
1065 mm_auth_rsa_verify_response(Key *key, BIGNUM *p, u_char response[16])
1066 {
1067 	Buffer m;
1068 	u_char *blob;
1069 	u_int blen;
1070 	int success = 0;
1071 
1072 	debug3("%s entering", __func__);
1073 
1074 	key->type = KEY_RSA;    /* XXX cheat for key_to_blob */
1075 	if (key_to_blob(key, &blob, &blen) == 0)
1076 		fatal("%s: key_to_blob failed", __func__);
1077 	key->type = KEY_RSA1;
1078 
1079 	buffer_init(&m);
1080 	buffer_put_string(&m, blob, blen);
1081 	buffer_put_string(&m, response, 16);
1082 	xfree(blob);
1083 
1084 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSARESPONSE, &m);
1085 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSARESPONSE, &m);
1086 
1087 	success = buffer_get_int(&m);
1088 	buffer_free(&m);
1089 
1090 	return (success);
1091 }
1092 
1093 #ifdef GSSAPI
1094 OM_uint32
1095 mm_ssh_gssapi_server_ctx(Gssctxt **ctx, gss_OID oid)
1096 {
1097 	Buffer m;
1098 	OM_uint32 major;
1099 
1100 	/* Client doesn't get to see the context */
1101 	*ctx = NULL;
1102 
1103 	buffer_init(&m);
1104 	buffer_put_string(&m, oid->elements, oid->length);
1105 
1106 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSETUP, &m);
1107 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSETUP, &m);
1108 
1109 	major = buffer_get_int(&m);
1110 
1111 	buffer_free(&m);
1112 	return (major);
1113 }
1114 
1115 OM_uint32
1116 mm_ssh_gssapi_accept_ctx(Gssctxt *ctx, gss_buffer_desc *in,
1117     gss_buffer_desc *out, OM_uint32 *flags)
1118 {
1119 	Buffer m;
1120 	OM_uint32 major;
1121 	u_int len;
1122 
1123 	buffer_init(&m);
1124 	buffer_put_string(&m, in->value, in->length);
1125 
1126 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSTEP, &m);
1127 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSTEP, &m);
1128 
1129 	major = buffer_get_int(&m);
1130 	out->value = buffer_get_string(&m, &len);
1131 	out->length = len;
1132 	if (flags)
1133 		*flags = buffer_get_int(&m);
1134 
1135 	buffer_free(&m);
1136 
1137 	return (major);
1138 }
1139 
1140 OM_uint32
1141 mm_ssh_gssapi_checkmic(Gssctxt *ctx, gss_buffer_t gssbuf, gss_buffer_t gssmic)
1142 {
1143 	Buffer m;
1144 	OM_uint32 major;
1145 
1146 	buffer_init(&m);
1147 	buffer_put_string(&m, gssbuf->value, gssbuf->length);
1148 	buffer_put_string(&m, gssmic->value, gssmic->length);
1149 
1150 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSCHECKMIC, &m);
1151 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSCHECKMIC,
1152 	    &m);
1153 
1154 	major = buffer_get_int(&m);
1155 	buffer_free(&m);
1156 	return(major);
1157 }
1158 
1159 int
1160 mm_ssh_gssapi_userok(char *user)
1161 {
1162 	Buffer m;
1163 	int authenticated = 0;
1164 
1165 	buffer_init(&m);
1166 
1167 	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSUSEROK, &m);
1168 	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSUSEROK,
1169 				  &m);
1170 
1171 	authenticated = buffer_get_int(&m);
1172 
1173 	buffer_free(&m);
1174 	debug3("%s: user %sauthenticated",__func__, authenticated ? "" : "not ");
1175 	return (authenticated);
1176 }
1177 #endif /* GSSAPI */
1178