xref: /openbsd-src/usr.bin/ssh/monitor.c (revision ac9b4aacc1da35008afea06a5d23c2f2dea9b93e)
1 /* $OpenBSD: monitor.c,v 1.117 2012/06/22 12:30:26 dtucker 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/wait.h>
30 #include <sys/socket.h>
31 #include <sys/tree.h>
32 #include <sys/param.h>
33 #include <sys/queue.h>
34 
35 #include <openssl/dh.h>
36 
37 #include <errno.h>
38 #include <fcntl.h>
39 #include <paths.h>
40 #include <poll.h>
41 #include <pwd.h>
42 #include <signal.h>
43 #include <stdlib.h>
44 #include <string.h>
45 
46 #include "atomicio.h"
47 #include "xmalloc.h"
48 #include "ssh.h"
49 #include "key.h"
50 #include "buffer.h"
51 #include "hostfile.h"
52 #include "auth.h"
53 #include "cipher.h"
54 #include "kex.h"
55 #include "dh.h"
56 #include <zlib.h>
57 #include "packet.h"
58 #include "auth-options.h"
59 #include "sshpty.h"
60 #include "channels.h"
61 #include "session.h"
62 #include "sshlogin.h"
63 #include "canohost.h"
64 #include "log.h"
65 #include "servconf.h"
66 #include "monitor.h"
67 #include "monitor_mm.h"
68 #ifdef GSSAPI
69 #include "ssh-gss.h"
70 #endif
71 #include "monitor_wrap.h"
72 #include "monitor_fdpass.h"
73 #include "misc.h"
74 #include "compat.h"
75 #include "ssh2.h"
76 #include "jpake.h"
77 #include "roaming.h"
78 
79 #ifdef GSSAPI
80 static Gssctxt *gsscontext = NULL;
81 #endif
82 
83 /* Imports */
84 extern ServerOptions options;
85 extern u_int utmp_len;
86 extern Newkeys *current_keys[];
87 extern z_stream incoming_stream;
88 extern z_stream outgoing_stream;
89 extern u_char session_id[];
90 extern Buffer auth_debug;
91 extern int auth_debug_init;
92 extern Buffer loginmsg;
93 
94 /* State exported from the child */
95 
96 struct {
97 	z_stream incoming;
98 	z_stream outgoing;
99 	u_char *keyin;
100 	u_int keyinlen;
101 	u_char *keyout;
102 	u_int keyoutlen;
103 	u_char *ivin;
104 	u_int ivinlen;
105 	u_char *ivout;
106 	u_int ivoutlen;
107 	u_char *ssh1key;
108 	u_int ssh1keylen;
109 	int ssh1cipher;
110 	int ssh1protoflags;
111 	u_char *input;
112 	u_int ilen;
113 	u_char *output;
114 	u_int olen;
115 	u_int64_t sent_bytes;
116 	u_int64_t recv_bytes;
117 } child_state;
118 
119 /* Functions on the monitor that answer unprivileged requests */
120 
121 int mm_answer_moduli(int, Buffer *);
122 int mm_answer_sign(int, Buffer *);
123 int mm_answer_pwnamallow(int, Buffer *);
124 int mm_answer_auth2_read_banner(int, Buffer *);
125 int mm_answer_authserv(int, Buffer *);
126 int mm_answer_authpassword(int, Buffer *);
127 int mm_answer_bsdauthquery(int, Buffer *);
128 int mm_answer_bsdauthrespond(int, Buffer *);
129 int mm_answer_skeyquery(int, Buffer *);
130 int mm_answer_skeyrespond(int, Buffer *);
131 int mm_answer_keyallowed(int, Buffer *);
132 int mm_answer_keyverify(int, Buffer *);
133 int mm_answer_pty(int, Buffer *);
134 int mm_answer_pty_cleanup(int, Buffer *);
135 int mm_answer_term(int, Buffer *);
136 int mm_answer_rsa_keyallowed(int, Buffer *);
137 int mm_answer_rsa_challenge(int, Buffer *);
138 int mm_answer_rsa_response(int, Buffer *);
139 int mm_answer_sesskey(int, Buffer *);
140 int mm_answer_sessid(int, Buffer *);
141 int mm_answer_jpake_get_pwdata(int, Buffer *);
142 int mm_answer_jpake_step1(int, Buffer *);
143 int mm_answer_jpake_step2(int, Buffer *);
144 int mm_answer_jpake_key_confirm(int, Buffer *);
145 int mm_answer_jpake_check_confirm(int, Buffer *);
146 
147 #ifdef GSSAPI
148 int mm_answer_gss_setup_ctx(int, Buffer *);
149 int mm_answer_gss_accept_ctx(int, Buffer *);
150 int mm_answer_gss_userok(int, Buffer *);
151 int mm_answer_gss_checkmic(int, Buffer *);
152 #endif
153 
154 static int monitor_read_log(struct monitor *);
155 
156 static Authctxt *authctxt;
157 static BIGNUM *ssh1_challenge = NULL;	/* used for ssh1 rsa auth */
158 
159 /* local state for key verify */
160 static u_char *key_blob = NULL;
161 static u_int key_bloblen = 0;
162 static int key_blobtype = MM_NOKEY;
163 static char *hostbased_cuser = NULL;
164 static char *hostbased_chost = NULL;
165 static char *auth_method = "unknown";
166 static u_int session_id2_len = 0;
167 static u_char *session_id2 = NULL;
168 static pid_t monitor_child_pid;
169 
170 struct mon_table {
171 	enum monitor_reqtype type;
172 	int flags;
173 	int (*f)(int, Buffer *);
174 };
175 
176 #define MON_ISAUTH	0x0004	/* Required for Authentication */
177 #define MON_AUTHDECIDE	0x0008	/* Decides Authentication */
178 #define MON_ONCE	0x0010	/* Disable after calling */
179 #define MON_ALOG	0x0020	/* Log auth attempt without authenticating */
180 
181 #define MON_AUTH	(MON_ISAUTH|MON_AUTHDECIDE)
182 
183 #define MON_PERMIT	0x1000	/* Request is permitted */
184 
185 struct mon_table mon_dispatch_proto20[] = {
186     {MONITOR_REQ_MODULI, MON_ONCE, mm_answer_moduli},
187     {MONITOR_REQ_SIGN, MON_ONCE, mm_answer_sign},
188     {MONITOR_REQ_PWNAM, MON_ONCE, mm_answer_pwnamallow},
189     {MONITOR_REQ_AUTHSERV, MON_ONCE, mm_answer_authserv},
190     {MONITOR_REQ_AUTH2_READ_BANNER, MON_ONCE, mm_answer_auth2_read_banner},
191     {MONITOR_REQ_AUTHPASSWORD, MON_AUTH, mm_answer_authpassword},
192     {MONITOR_REQ_BSDAUTHQUERY, MON_ISAUTH, mm_answer_bsdauthquery},
193     {MONITOR_REQ_BSDAUTHRESPOND, MON_AUTH, mm_answer_bsdauthrespond},
194     {MONITOR_REQ_KEYALLOWED, MON_ISAUTH, mm_answer_keyallowed},
195     {MONITOR_REQ_KEYVERIFY, MON_AUTH, mm_answer_keyverify},
196 #ifdef GSSAPI
197     {MONITOR_REQ_GSSSETUP, MON_ISAUTH, mm_answer_gss_setup_ctx},
198     {MONITOR_REQ_GSSSTEP, MON_ISAUTH, mm_answer_gss_accept_ctx},
199     {MONITOR_REQ_GSSUSEROK, MON_AUTH, mm_answer_gss_userok},
200     {MONITOR_REQ_GSSCHECKMIC, MON_ISAUTH, mm_answer_gss_checkmic},
201 #endif
202 #ifdef JPAKE
203     {MONITOR_REQ_JPAKE_GET_PWDATA, MON_ONCE, mm_answer_jpake_get_pwdata},
204     {MONITOR_REQ_JPAKE_STEP1, MON_ISAUTH, mm_answer_jpake_step1},
205     {MONITOR_REQ_JPAKE_STEP2, MON_ONCE, mm_answer_jpake_step2},
206     {MONITOR_REQ_JPAKE_KEY_CONFIRM, MON_ONCE, mm_answer_jpake_key_confirm},
207     {MONITOR_REQ_JPAKE_CHECK_CONFIRM, MON_AUTH, mm_answer_jpake_check_confirm},
208 #endif
209     {0, 0, NULL}
210 };
211 
212 struct mon_table mon_dispatch_postauth20[] = {
213     {MONITOR_REQ_MODULI, 0, mm_answer_moduli},
214     {MONITOR_REQ_SIGN, 0, mm_answer_sign},
215     {MONITOR_REQ_PTY, 0, mm_answer_pty},
216     {MONITOR_REQ_PTYCLEANUP, 0, mm_answer_pty_cleanup},
217     {MONITOR_REQ_TERM, 0, mm_answer_term},
218     {0, 0, NULL}
219 };
220 
221 struct mon_table mon_dispatch_proto15[] = {
222     {MONITOR_REQ_PWNAM, MON_ONCE, mm_answer_pwnamallow},
223     {MONITOR_REQ_SESSKEY, MON_ONCE, mm_answer_sesskey},
224     {MONITOR_REQ_SESSID, MON_ONCE, mm_answer_sessid},
225     {MONITOR_REQ_AUTHPASSWORD, MON_AUTH, mm_answer_authpassword},
226     {MONITOR_REQ_RSAKEYALLOWED, MON_ISAUTH|MON_ALOG, mm_answer_rsa_keyallowed},
227     {MONITOR_REQ_KEYALLOWED, MON_ISAUTH|MON_ALOG, mm_answer_keyallowed},
228     {MONITOR_REQ_RSACHALLENGE, MON_ONCE, mm_answer_rsa_challenge},
229     {MONITOR_REQ_RSARESPONSE, MON_ONCE|MON_AUTHDECIDE, mm_answer_rsa_response},
230     {MONITOR_REQ_BSDAUTHQUERY, MON_ISAUTH, mm_answer_bsdauthquery},
231     {MONITOR_REQ_BSDAUTHRESPOND, MON_AUTH, mm_answer_bsdauthrespond},
232     {0, 0, NULL}
233 };
234 
235 struct mon_table mon_dispatch_postauth15[] = {
236     {MONITOR_REQ_PTY, MON_ONCE, mm_answer_pty},
237     {MONITOR_REQ_PTYCLEANUP, MON_ONCE, mm_answer_pty_cleanup},
238     {MONITOR_REQ_TERM, 0, mm_answer_term},
239     {0, 0, NULL}
240 };
241 
242 struct mon_table *mon_dispatch;
243 
244 /* Specifies if a certain message is allowed at the moment */
245 
246 static void
247 monitor_permit(struct mon_table *ent, enum monitor_reqtype type, int permit)
248 {
249 	while (ent->f != NULL) {
250 		if (ent->type == type) {
251 			ent->flags &= ~MON_PERMIT;
252 			ent->flags |= permit ? MON_PERMIT : 0;
253 			return;
254 		}
255 		ent++;
256 	}
257 }
258 
259 static void
260 monitor_permit_authentications(int permit)
261 {
262 	struct mon_table *ent = mon_dispatch;
263 
264 	while (ent->f != NULL) {
265 		if (ent->flags & MON_AUTH) {
266 			ent->flags &= ~MON_PERMIT;
267 			ent->flags |= permit ? MON_PERMIT : 0;
268 		}
269 		ent++;
270 	}
271 }
272 
273 void
274 monitor_child_preauth(Authctxt *_authctxt, struct monitor *pmonitor)
275 {
276 	struct mon_table *ent;
277 	int authenticated = 0;
278 
279 	debug3("preauth child monitor started");
280 
281 	close(pmonitor->m_recvfd);
282 	close(pmonitor->m_log_sendfd);
283 	pmonitor->m_log_sendfd = pmonitor->m_recvfd = -1;
284 
285 	authctxt = _authctxt;
286 	memset(authctxt, 0, sizeof(*authctxt));
287 
288 	if (compat20) {
289 		mon_dispatch = mon_dispatch_proto20;
290 
291 		/* Permit requests for moduli and signatures */
292 		monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
293 		monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
294 	} else {
295 		mon_dispatch = mon_dispatch_proto15;
296 
297 		monitor_permit(mon_dispatch, MONITOR_REQ_SESSKEY, 1);
298 	}
299 
300 	/* The first few requests do not require asynchronous access */
301 	while (!authenticated) {
302 		auth_method = "unknown";
303 		authenticated = (monitor_read(pmonitor, mon_dispatch, &ent) == 1);
304 		if (authenticated) {
305 			if (!(ent->flags & MON_AUTHDECIDE))
306 				fatal("%s: unexpected authentication from %d",
307 				    __func__, ent->type);
308 			if (authctxt->pw->pw_uid == 0 &&
309 			    !auth_root_allowed(auth_method))
310 				authenticated = 0;
311 		}
312 
313 		if (ent->flags & (MON_AUTHDECIDE|MON_ALOG)) {
314 			auth_log(authctxt, authenticated, auth_method,
315 			    compat20 ? " ssh2" : "");
316 			if (!authenticated)
317 				authctxt->failures++;
318 		}
319 #ifdef JPAKE
320 		/* Cleanup JPAKE context after authentication */
321 		if (ent->flags & MON_AUTHDECIDE) {
322 			if (authctxt->jpake_ctx != NULL) {
323 				jpake_free(authctxt->jpake_ctx);
324 				authctxt->jpake_ctx = NULL;
325 			}
326 		}
327 #endif
328 	}
329 
330 	/* Drain any buffered messages from the child */
331 	while (pmonitor->m_log_recvfd != -1 && monitor_read_log(pmonitor) == 0)
332 		;
333 
334 	if (!authctxt->valid)
335 		fatal("%s: authenticated invalid user", __func__);
336 	if (strcmp(auth_method, "unknown") == 0)
337 		fatal("%s: authentication method name unknown", __func__);
338 
339 	debug("%s: %s has been authenticated by privileged process",
340 	    __func__, authctxt->user);
341 
342 	mm_get_keystate(pmonitor);
343 
344 	close(pmonitor->m_sendfd);
345 	close(pmonitor->m_log_recvfd);
346 	pmonitor->m_sendfd = pmonitor->m_log_recvfd = -1;
347 }
348 
349 static void
350 monitor_set_child_handler(pid_t pid)
351 {
352 	monitor_child_pid = pid;
353 }
354 
355 static void
356 monitor_child_handler(int sig)
357 {
358 	kill(monitor_child_pid, sig);
359 }
360 
361 void
362 monitor_child_postauth(struct monitor *pmonitor)
363 {
364 	close(pmonitor->m_recvfd);
365 	pmonitor->m_recvfd = -1;
366 
367 	monitor_set_child_handler(pmonitor->m_pid);
368 	signal(SIGHUP, &monitor_child_handler);
369 	signal(SIGTERM, &monitor_child_handler);
370 	signal(SIGINT, &monitor_child_handler);
371 
372 	if (compat20) {
373 		mon_dispatch = mon_dispatch_postauth20;
374 
375 		/* Permit requests for moduli and signatures */
376 		monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
377 		monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
378 		monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1);
379 	} else {
380 		mon_dispatch = mon_dispatch_postauth15;
381 		monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1);
382 	}
383 	if (!no_pty_flag) {
384 		monitor_permit(mon_dispatch, MONITOR_REQ_PTY, 1);
385 		monitor_permit(mon_dispatch, MONITOR_REQ_PTYCLEANUP, 1);
386 	}
387 
388 	for (;;)
389 		monitor_read(pmonitor, mon_dispatch, NULL);
390 }
391 
392 void
393 monitor_sync(struct monitor *pmonitor)
394 {
395 	if (options.compression) {
396 		/* The member allocation is not visible, so sync it */
397 		mm_share_sync(&pmonitor->m_zlib, &pmonitor->m_zback);
398 	}
399 }
400 
401 static int
402 monitor_read_log(struct monitor *pmonitor)
403 {
404 	Buffer logmsg;
405 	u_int len, level;
406 	char *msg;
407 
408 	buffer_init(&logmsg);
409 
410 	/* Read length */
411 	buffer_append_space(&logmsg, 4);
412 	if (atomicio(read, pmonitor->m_log_recvfd,
413 	    buffer_ptr(&logmsg), buffer_len(&logmsg)) != buffer_len(&logmsg)) {
414 		if (errno == EPIPE) {
415 			buffer_free(&logmsg);
416 			debug("%s: child log fd closed", __func__);
417 			close(pmonitor->m_log_recvfd);
418 			pmonitor->m_log_recvfd = -1;
419 			return -1;
420 		}
421 		fatal("%s: log fd read: %s", __func__, strerror(errno));
422 	}
423 	len = buffer_get_int(&logmsg);
424 	if (len <= 4 || len > 8192)
425 		fatal("%s: invalid log message length %u", __func__, len);
426 
427 	/* Read severity, message */
428 	buffer_clear(&logmsg);
429 	buffer_append_space(&logmsg, len);
430 	if (atomicio(read, pmonitor->m_log_recvfd,
431 	    buffer_ptr(&logmsg), buffer_len(&logmsg)) != buffer_len(&logmsg))
432 		fatal("%s: log fd read: %s", __func__, strerror(errno));
433 
434 	/* Log it */
435 	level = buffer_get_int(&logmsg);
436 	msg = buffer_get_string(&logmsg, NULL);
437 	if (log_level_name(level) == NULL)
438 		fatal("%s: invalid log level %u (corrupted message?)",
439 		    __func__, level);
440 	do_log2(level, "%s [preauth]", msg);
441 
442 	buffer_free(&logmsg);
443 	xfree(msg);
444 
445 	return 0;
446 }
447 
448 int
449 monitor_read(struct monitor *pmonitor, struct mon_table *ent,
450     struct mon_table **pent)
451 {
452 	Buffer m;
453 	int ret;
454 	u_char type;
455 	struct pollfd pfd[2];
456 
457 	for (;;) {
458 		bzero(&pfd, sizeof(pfd));
459 		pfd[0].fd = pmonitor->m_sendfd;
460 		pfd[0].events = POLLIN;
461 		pfd[1].fd = pmonitor->m_log_recvfd;
462 		pfd[1].events = pfd[1].fd == -1 ? 0 : POLLIN;
463 		if (poll(pfd, pfd[1].fd == -1 ? 1 : 2, -1) == -1) {
464 			if (errno == EINTR || errno == EAGAIN)
465 				continue;
466 			fatal("%s: poll: %s", __func__, strerror(errno));
467 		}
468 		if (pfd[1].revents) {
469 			/*
470 			 * Drain all log messages before processing next
471 			 * monitor request.
472 			 */
473 			monitor_read_log(pmonitor);
474 			continue;
475 		}
476 		if (pfd[0].revents)
477 			break;  /* Continues below */
478 	}
479 
480 	buffer_init(&m);
481 
482 	mm_request_receive(pmonitor->m_sendfd, &m);
483 	type = buffer_get_char(&m);
484 
485 	debug3("%s: checking request %d", __func__, type);
486 
487 	while (ent->f != NULL) {
488 		if (ent->type == type)
489 			break;
490 		ent++;
491 	}
492 
493 	if (ent->f != NULL) {
494 		if (!(ent->flags & MON_PERMIT))
495 			fatal("%s: unpermitted request %d", __func__,
496 			    type);
497 		ret = (*ent->f)(pmonitor->m_sendfd, &m);
498 		buffer_free(&m);
499 
500 		/* The child may use this request only once, disable it */
501 		if (ent->flags & MON_ONCE) {
502 			debug2("%s: %d used once, disabling now", __func__,
503 			    type);
504 			ent->flags &= ~MON_PERMIT;
505 		}
506 
507 		if (pent != NULL)
508 			*pent = ent;
509 
510 		return ret;
511 	}
512 
513 	fatal("%s: unsupported request: %d", __func__, type);
514 
515 	/* NOTREACHED */
516 	return (-1);
517 }
518 
519 /* allowed key state */
520 static int
521 monitor_allowed_key(u_char *blob, u_int bloblen)
522 {
523 	/* make sure key is allowed */
524 	if (key_blob == NULL || key_bloblen != bloblen ||
525 	    timingsafe_bcmp(key_blob, blob, key_bloblen))
526 		return (0);
527 	return (1);
528 }
529 
530 static void
531 monitor_reset_key_state(void)
532 {
533 	/* reset state */
534 	if (key_blob != NULL)
535 		xfree(key_blob);
536 	if (hostbased_cuser != NULL)
537 		xfree(hostbased_cuser);
538 	if (hostbased_chost != NULL)
539 		xfree(hostbased_chost);
540 	key_blob = NULL;
541 	key_bloblen = 0;
542 	key_blobtype = MM_NOKEY;
543 	hostbased_cuser = NULL;
544 	hostbased_chost = NULL;
545 }
546 
547 int
548 mm_answer_moduli(int sock, Buffer *m)
549 {
550 	DH *dh;
551 	int min, want, max;
552 
553 	min = buffer_get_int(m);
554 	want = buffer_get_int(m);
555 	max = buffer_get_int(m);
556 
557 	debug3("%s: got parameters: %d %d %d",
558 	    __func__, min, want, max);
559 	/* We need to check here, too, in case the child got corrupted */
560 	if (max < min || want < min || max < want)
561 		fatal("%s: bad parameters: %d %d %d",
562 		    __func__, min, want, max);
563 
564 	buffer_clear(m);
565 
566 	dh = choose_dh(min, want, max);
567 	if (dh == NULL) {
568 		buffer_put_char(m, 0);
569 		return (0);
570 	} else {
571 		/* Send first bignum */
572 		buffer_put_char(m, 1);
573 		buffer_put_bignum2(m, dh->p);
574 		buffer_put_bignum2(m, dh->g);
575 
576 		DH_free(dh);
577 	}
578 	mm_request_send(sock, MONITOR_ANS_MODULI, m);
579 	return (0);
580 }
581 
582 int
583 mm_answer_sign(int sock, Buffer *m)
584 {
585 	Key *key;
586 	u_char *p;
587 	u_char *signature;
588 	u_int siglen, datlen;
589 	int keyid;
590 
591 	debug3("%s", __func__);
592 
593 	keyid = buffer_get_int(m);
594 	p = buffer_get_string(m, &datlen);
595 
596 	/*
597 	 * Supported KEX types use SHA1 (20 bytes), SHA256 (32 bytes),
598 	 * SHA384 (48 bytes) and SHA512 (64 bytes).
599 	 */
600 	if (datlen != 20 && datlen != 32 && datlen != 48 && datlen != 64)
601 		fatal("%s: data length incorrect: %u", __func__, datlen);
602 
603 	/* save session id, it will be passed on the first call */
604 	if (session_id2_len == 0) {
605 		session_id2_len = datlen;
606 		session_id2 = xmalloc(session_id2_len);
607 		memcpy(session_id2, p, session_id2_len);
608 	}
609 
610 	if ((key = get_hostkey_by_index(keyid)) == NULL)
611 		fatal("%s: no hostkey from index %d", __func__, keyid);
612 	if (key_sign(key, &signature, &siglen, p, datlen) < 0)
613 		fatal("%s: key_sign failed", __func__);
614 
615 	debug3("%s: signature %p(%u)", __func__, signature, siglen);
616 
617 	buffer_clear(m);
618 	buffer_put_string(m, signature, siglen);
619 
620 	xfree(p);
621 	xfree(signature);
622 
623 	mm_request_send(sock, MONITOR_ANS_SIGN, m);
624 
625 	/* Turn on permissions for getpwnam */
626 	monitor_permit(mon_dispatch, MONITOR_REQ_PWNAM, 1);
627 
628 	return (0);
629 }
630 
631 /* Retrieves the password entry and also checks if the user is permitted */
632 
633 int
634 mm_answer_pwnamallow(int sock, Buffer *m)
635 {
636 	char *username;
637 	struct passwd *pwent;
638 	int allowed = 0;
639 	u_int i;
640 
641 	debug3("%s", __func__);
642 
643 	if (authctxt->attempt++ != 0)
644 		fatal("%s: multiple attempts for getpwnam", __func__);
645 
646 	username = buffer_get_string(m, NULL);
647 
648 	pwent = getpwnamallow(username);
649 
650 	authctxt->user = xstrdup(username);
651 	setproctitle("%s [priv]", pwent ? username : "unknown");
652 	xfree(username);
653 
654 	buffer_clear(m);
655 
656 	if (pwent == NULL) {
657 		buffer_put_char(m, 0);
658 		authctxt->pw = fakepw();
659 		goto out;
660 	}
661 
662 	allowed = 1;
663 	authctxt->pw = pwent;
664 	authctxt->valid = 1;
665 
666 	buffer_put_char(m, 1);
667 	buffer_put_string(m, pwent, sizeof(struct passwd));
668 	buffer_put_cstring(m, pwent->pw_name);
669 	buffer_put_cstring(m, "*");
670 	buffer_put_cstring(m, pwent->pw_gecos);
671 	buffer_put_cstring(m, pwent->pw_class);
672 	buffer_put_cstring(m, pwent->pw_dir);
673 	buffer_put_cstring(m, pwent->pw_shell);
674 
675  out:
676 	buffer_put_string(m, &options, sizeof(options));
677 
678 #define M_CP_STROPT(x) do { \
679 		if (options.x != NULL) \
680 			buffer_put_cstring(m, options.x); \
681 	} while (0)
682 #define M_CP_STRARRAYOPT(x, nx) do { \
683 		for (i = 0; i < options.nx; i++) \
684 			buffer_put_cstring(m, options.x[i]); \
685 	} while (0)
686 	/* See comment in servconf.h */
687 	COPY_MATCH_STRING_OPTS();
688 #undef M_CP_STROPT
689 #undef M_CP_STRARRAYOPT
690 
691 	debug3("%s: sending MONITOR_ANS_PWNAM: %d", __func__, allowed);
692 	mm_request_send(sock, MONITOR_ANS_PWNAM, m);
693 
694 	/* For SSHv1 allow authentication now */
695 	if (!compat20)
696 		monitor_permit_authentications(1);
697 	else {
698 		/* Allow service/style information on the auth context */
699 		monitor_permit(mon_dispatch, MONITOR_REQ_AUTHSERV, 1);
700 		monitor_permit(mon_dispatch, MONITOR_REQ_AUTH2_READ_BANNER, 1);
701 	}
702 
703 	return (0);
704 }
705 
706 int mm_answer_auth2_read_banner(int sock, Buffer *m)
707 {
708 	char *banner;
709 
710 	buffer_clear(m);
711 	banner = auth2_read_banner();
712 	buffer_put_cstring(m, banner != NULL ? banner : "");
713 	mm_request_send(sock, MONITOR_ANS_AUTH2_READ_BANNER, m);
714 
715 	if (banner != NULL)
716 		xfree(banner);
717 
718 	return (0);
719 }
720 
721 int
722 mm_answer_authserv(int sock, Buffer *m)
723 {
724 	monitor_permit_authentications(1);
725 
726 	authctxt->service = buffer_get_string(m, NULL);
727 	authctxt->style = buffer_get_string(m, NULL);
728 	debug3("%s: service=%s, style=%s",
729 	    __func__, authctxt->service, authctxt->style);
730 
731 	if (strlen(authctxt->style) == 0) {
732 		xfree(authctxt->style);
733 		authctxt->style = NULL;
734 	}
735 
736 	return (0);
737 }
738 
739 int
740 mm_answer_authpassword(int sock, Buffer *m)
741 {
742 	static int call_count;
743 	char *passwd;
744 	int authenticated;
745 	u_int plen;
746 
747 	passwd = buffer_get_string(m, &plen);
748 	/* Only authenticate if the context is valid */
749 	authenticated = options.password_authentication &&
750 	    auth_password(authctxt, passwd);
751 	memset(passwd, 0, strlen(passwd));
752 	xfree(passwd);
753 
754 	buffer_clear(m);
755 	buffer_put_int(m, authenticated);
756 
757 	debug3("%s: sending result %d", __func__, authenticated);
758 	mm_request_send(sock, MONITOR_ANS_AUTHPASSWORD, m);
759 
760 	call_count++;
761 	if (plen == 0 && call_count == 1)
762 		auth_method = "none";
763 	else
764 		auth_method = "password";
765 
766 	/* Causes monitor loop to terminate if authenticated */
767 	return (authenticated);
768 }
769 
770 int
771 mm_answer_bsdauthquery(int sock, Buffer *m)
772 {
773 	char *name, *infotxt;
774 	u_int numprompts;
775 	u_int *echo_on;
776 	char **prompts;
777 	u_int success;
778 
779 	success = bsdauth_query(authctxt, &name, &infotxt, &numprompts,
780 	    &prompts, &echo_on) < 0 ? 0 : 1;
781 
782 	buffer_clear(m);
783 	buffer_put_int(m, success);
784 	if (success)
785 		buffer_put_cstring(m, prompts[0]);
786 
787 	debug3("%s: sending challenge success: %u", __func__, success);
788 	mm_request_send(sock, MONITOR_ANS_BSDAUTHQUERY, m);
789 
790 	if (success) {
791 		xfree(name);
792 		xfree(infotxt);
793 		xfree(prompts);
794 		xfree(echo_on);
795 	}
796 
797 	return (0);
798 }
799 
800 int
801 mm_answer_bsdauthrespond(int sock, Buffer *m)
802 {
803 	char *response;
804 	int authok;
805 
806 	if (authctxt->as == 0)
807 		fatal("%s: no bsd auth session", __func__);
808 
809 	response = buffer_get_string(m, NULL);
810 	authok = options.challenge_response_authentication &&
811 	    auth_userresponse(authctxt->as, response, 0);
812 	authctxt->as = NULL;
813 	debug3("%s: <%s> = <%d>", __func__, response, authok);
814 	xfree(response);
815 
816 	buffer_clear(m);
817 	buffer_put_int(m, authok);
818 
819 	debug3("%s: sending authenticated: %d", __func__, authok);
820 	mm_request_send(sock, MONITOR_ANS_BSDAUTHRESPOND, m);
821 
822 	auth_method = "bsdauth";
823 
824 	return (authok != 0);
825 }
826 
827 int
828 mm_answer_keyallowed(int sock, Buffer *m)
829 {
830 	Key *key;
831 	char *cuser, *chost;
832 	u_char *blob;
833 	u_int bloblen;
834 	enum mm_keytype type = 0;
835 	int allowed = 0;
836 
837 	debug3("%s entering", __func__);
838 
839 	type = buffer_get_int(m);
840 	cuser = buffer_get_string(m, NULL);
841 	chost = buffer_get_string(m, NULL);
842 	blob = buffer_get_string(m, &bloblen);
843 
844 	key = key_from_blob(blob, bloblen);
845 
846 	if ((compat20 && type == MM_RSAHOSTKEY) ||
847 	    (!compat20 && type != MM_RSAHOSTKEY))
848 		fatal("%s: key type and protocol mismatch", __func__);
849 
850 	debug3("%s: key_from_blob: %p", __func__, key);
851 
852 	if (key != NULL && authctxt->valid) {
853 		switch (type) {
854 		case MM_USERKEY:
855 			allowed = options.pubkey_authentication &&
856 			    user_key_allowed(authctxt->pw, key);
857 			auth_method = "publickey";
858 			if (options.pubkey_authentication && allowed != 1)
859 				auth_clear_options();
860 			break;
861 		case MM_HOSTKEY:
862 			allowed = options.hostbased_authentication &&
863 			    hostbased_key_allowed(authctxt->pw,
864 			    cuser, chost, key);
865 			auth_method = "hostbased";
866 			break;
867 		case MM_RSAHOSTKEY:
868 			key->type = KEY_RSA1; /* XXX */
869 			allowed = options.rhosts_rsa_authentication &&
870 			    auth_rhosts_rsa_key_allowed(authctxt->pw,
871 			    cuser, chost, key);
872 			if (options.rhosts_rsa_authentication && allowed != 1)
873 				auth_clear_options();
874 			auth_method = "rsa";
875 			break;
876 		default:
877 			fatal("%s: unknown key type %d", __func__, type);
878 			break;
879 		}
880 	}
881 	if (key != NULL)
882 		key_free(key);
883 
884 	/* clear temporarily storage (used by verify) */
885 	monitor_reset_key_state();
886 
887 	if (allowed) {
888 		/* Save temporarily for comparison in verify */
889 		key_blob = blob;
890 		key_bloblen = bloblen;
891 		key_blobtype = type;
892 		hostbased_cuser = cuser;
893 		hostbased_chost = chost;
894 	} else {
895 		/* Log failed attempt */
896 		auth_log(authctxt, 0, auth_method, compat20 ? " ssh2" : "");
897 		xfree(blob);
898 		xfree(cuser);
899 		xfree(chost);
900 	}
901 
902 	debug3("%s: key %p is %s",
903 	    __func__, key, allowed ? "allowed" : "not allowed");
904 
905 	buffer_clear(m);
906 	buffer_put_int(m, allowed);
907 	buffer_put_int(m, forced_command != NULL);
908 
909 	mm_request_send(sock, MONITOR_ANS_KEYALLOWED, m);
910 
911 	if (type == MM_RSAHOSTKEY)
912 		monitor_permit(mon_dispatch, MONITOR_REQ_RSACHALLENGE, allowed);
913 
914 	return (0);
915 }
916 
917 static int
918 monitor_valid_userblob(u_char *data, u_int datalen)
919 {
920 	Buffer b;
921 	char *p;
922 	u_int len;
923 	int fail = 0;
924 
925 	buffer_init(&b);
926 	buffer_append(&b, data, datalen);
927 
928 	if (datafellows & SSH_OLD_SESSIONID) {
929 		p = buffer_ptr(&b);
930 		len = buffer_len(&b);
931 		if ((session_id2 == NULL) ||
932 		    (len < session_id2_len) ||
933 		    (timingsafe_bcmp(p, session_id2, session_id2_len) != 0))
934 			fail++;
935 		buffer_consume(&b, session_id2_len);
936 	} else {
937 		p = buffer_get_string(&b, &len);
938 		if ((session_id2 == NULL) ||
939 		    (len != session_id2_len) ||
940 		    (timingsafe_bcmp(p, session_id2, session_id2_len) != 0))
941 			fail++;
942 		xfree(p);
943 	}
944 	if (buffer_get_char(&b) != SSH2_MSG_USERAUTH_REQUEST)
945 		fail++;
946 	p = buffer_get_string(&b, NULL);
947 	if (strcmp(authctxt->user, p) != 0) {
948 		logit("wrong user name passed to monitor: expected %s != %.100s",
949 		    authctxt->user, p);
950 		fail++;
951 	}
952 	xfree(p);
953 	buffer_skip_string(&b);
954 	if (datafellows & SSH_BUG_PKAUTH) {
955 		if (!buffer_get_char(&b))
956 			fail++;
957 	} else {
958 		p = buffer_get_string(&b, NULL);
959 		if (strcmp("publickey", p) != 0)
960 			fail++;
961 		xfree(p);
962 		if (!buffer_get_char(&b))
963 			fail++;
964 		buffer_skip_string(&b);
965 	}
966 	buffer_skip_string(&b);
967 	if (buffer_len(&b) != 0)
968 		fail++;
969 	buffer_free(&b);
970 	return (fail == 0);
971 }
972 
973 static int
974 monitor_valid_hostbasedblob(u_char *data, u_int datalen, char *cuser,
975     char *chost)
976 {
977 	Buffer b;
978 	char *p;
979 	u_int len;
980 	int fail = 0;
981 
982 	buffer_init(&b);
983 	buffer_append(&b, data, datalen);
984 
985 	p = buffer_get_string(&b, &len);
986 	if ((session_id2 == NULL) ||
987 	    (len != session_id2_len) ||
988 	    (timingsafe_bcmp(p, session_id2, session_id2_len) != 0))
989 		fail++;
990 	xfree(p);
991 
992 	if (buffer_get_char(&b) != SSH2_MSG_USERAUTH_REQUEST)
993 		fail++;
994 	p = buffer_get_string(&b, NULL);
995 	if (strcmp(authctxt->user, p) != 0) {
996 		logit("wrong user name passed to monitor: expected %s != %.100s",
997 		    authctxt->user, p);
998 		fail++;
999 	}
1000 	xfree(p);
1001 	buffer_skip_string(&b);	/* service */
1002 	p = buffer_get_string(&b, NULL);
1003 	if (strcmp(p, "hostbased") != 0)
1004 		fail++;
1005 	xfree(p);
1006 	buffer_skip_string(&b);	/* pkalg */
1007 	buffer_skip_string(&b);	/* pkblob */
1008 
1009 	/* verify client host, strip trailing dot if necessary */
1010 	p = buffer_get_string(&b, NULL);
1011 	if (((len = strlen(p)) > 0) && p[len - 1] == '.')
1012 		p[len - 1] = '\0';
1013 	if (strcmp(p, chost) != 0)
1014 		fail++;
1015 	xfree(p);
1016 
1017 	/* verify client user */
1018 	p = buffer_get_string(&b, NULL);
1019 	if (strcmp(p, cuser) != 0)
1020 		fail++;
1021 	xfree(p);
1022 
1023 	if (buffer_len(&b) != 0)
1024 		fail++;
1025 	buffer_free(&b);
1026 	return (fail == 0);
1027 }
1028 
1029 int
1030 mm_answer_keyverify(int sock, Buffer *m)
1031 {
1032 	Key *key;
1033 	u_char *signature, *data, *blob;
1034 	u_int signaturelen, datalen, bloblen;
1035 	int verified = 0;
1036 	int valid_data = 0;
1037 
1038 	blob = buffer_get_string(m, &bloblen);
1039 	signature = buffer_get_string(m, &signaturelen);
1040 	data = buffer_get_string(m, &datalen);
1041 
1042 	if (hostbased_cuser == NULL || hostbased_chost == NULL ||
1043 	  !monitor_allowed_key(blob, bloblen))
1044 		fatal("%s: bad key, not previously allowed", __func__);
1045 
1046 	key = key_from_blob(blob, bloblen);
1047 	if (key == NULL)
1048 		fatal("%s: bad public key blob", __func__);
1049 
1050 	switch (key_blobtype) {
1051 	case MM_USERKEY:
1052 		valid_data = monitor_valid_userblob(data, datalen);
1053 		break;
1054 	case MM_HOSTKEY:
1055 		valid_data = monitor_valid_hostbasedblob(data, datalen,
1056 		    hostbased_cuser, hostbased_chost);
1057 		break;
1058 	default:
1059 		valid_data = 0;
1060 		break;
1061 	}
1062 	if (!valid_data)
1063 		fatal("%s: bad signature data blob", __func__);
1064 
1065 	verified = key_verify(key, signature, signaturelen, data, datalen);
1066 	debug3("%s: key %p signature %s",
1067 	    __func__, key, (verified == 1) ? "verified" : "unverified");
1068 
1069 	key_free(key);
1070 	xfree(blob);
1071 	xfree(signature);
1072 	xfree(data);
1073 
1074 	auth_method = key_blobtype == MM_USERKEY ? "publickey" : "hostbased";
1075 
1076 	monitor_reset_key_state();
1077 
1078 	buffer_clear(m);
1079 	buffer_put_int(m, verified);
1080 	mm_request_send(sock, MONITOR_ANS_KEYVERIFY, m);
1081 
1082 	return (verified == 1);
1083 }
1084 
1085 static void
1086 mm_record_login(Session *s, struct passwd *pw)
1087 {
1088 	socklen_t fromlen;
1089 	struct sockaddr_storage from;
1090 
1091 	/*
1092 	 * Get IP address of client. If the connection is not a socket, let
1093 	 * the address be 0.0.0.0.
1094 	 */
1095 	memset(&from, 0, sizeof(from));
1096 	fromlen = sizeof(from);
1097 	if (packet_connection_is_on_socket()) {
1098 		if (getpeername(packet_get_connection_in(),
1099 		    (struct sockaddr *)&from, &fromlen) < 0) {
1100 			debug("getpeername: %.100s", strerror(errno));
1101 			cleanup_exit(255);
1102 		}
1103 	}
1104 	/* Record that there was a login on that tty from the remote host. */
1105 	record_login(s->pid, s->tty, pw->pw_name, pw->pw_uid,
1106 	    get_remote_name_or_ip(utmp_len, options.use_dns),
1107 	    (struct sockaddr *)&from, fromlen);
1108 }
1109 
1110 static void
1111 mm_session_close(Session *s)
1112 {
1113 	debug3("%s: session %d pid %ld", __func__, s->self, (long)s->pid);
1114 	if (s->ttyfd != -1) {
1115 		debug3("%s: tty %s ptyfd %d", __func__, s->tty, s->ptyfd);
1116 		session_pty_cleanup2(s);
1117 	}
1118 	session_unused(s->self);
1119 }
1120 
1121 int
1122 mm_answer_pty(int sock, Buffer *m)
1123 {
1124 	extern struct monitor *pmonitor;
1125 	Session *s;
1126 	int res, fd0;
1127 
1128 	debug3("%s entering", __func__);
1129 
1130 	buffer_clear(m);
1131 	s = session_new();
1132 	if (s == NULL)
1133 		goto error;
1134 	s->authctxt = authctxt;
1135 	s->pw = authctxt->pw;
1136 	s->pid = pmonitor->m_pid;
1137 	res = pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty));
1138 	if (res == 0)
1139 		goto error;
1140 	pty_setowner(authctxt->pw, s->tty);
1141 
1142 	buffer_put_int(m, 1);
1143 	buffer_put_cstring(m, s->tty);
1144 
1145 	/* We need to trick ttyslot */
1146 	if (dup2(s->ttyfd, 0) == -1)
1147 		fatal("%s: dup2", __func__);
1148 
1149 	mm_record_login(s, authctxt->pw);
1150 
1151 	/* Now we can close the file descriptor again */
1152 	close(0);
1153 
1154 	/* send messages generated by record_login */
1155 	buffer_put_string(m, buffer_ptr(&loginmsg), buffer_len(&loginmsg));
1156 	buffer_clear(&loginmsg);
1157 
1158 	mm_request_send(sock, MONITOR_ANS_PTY, m);
1159 
1160 	if (mm_send_fd(sock, s->ptyfd) == -1 ||
1161 	    mm_send_fd(sock, s->ttyfd) == -1)
1162 		fatal("%s: send fds failed", __func__);
1163 
1164 	/* make sure nothing uses fd 0 */
1165 	if ((fd0 = open(_PATH_DEVNULL, O_RDONLY)) < 0)
1166 		fatal("%s: open(/dev/null): %s", __func__, strerror(errno));
1167 	if (fd0 != 0)
1168 		error("%s: fd0 %d != 0", __func__, fd0);
1169 
1170 	/* slave is not needed */
1171 	close(s->ttyfd);
1172 	s->ttyfd = s->ptyfd;
1173 	/* no need to dup() because nobody closes ptyfd */
1174 	s->ptymaster = s->ptyfd;
1175 
1176 	debug3("%s: tty %s ptyfd %d", __func__, s->tty, s->ttyfd);
1177 
1178 	return (0);
1179 
1180  error:
1181 	if (s != NULL)
1182 		mm_session_close(s);
1183 	buffer_put_int(m, 0);
1184 	mm_request_send(sock, MONITOR_ANS_PTY, m);
1185 	return (0);
1186 }
1187 
1188 int
1189 mm_answer_pty_cleanup(int sock, Buffer *m)
1190 {
1191 	Session *s;
1192 	char *tty;
1193 
1194 	debug3("%s entering", __func__);
1195 
1196 	tty = buffer_get_string(m, NULL);
1197 	if ((s = session_by_tty(tty)) != NULL)
1198 		mm_session_close(s);
1199 	buffer_clear(m);
1200 	xfree(tty);
1201 	return (0);
1202 }
1203 
1204 int
1205 mm_answer_sesskey(int sock, Buffer *m)
1206 {
1207 	BIGNUM *p;
1208 	int rsafail;
1209 
1210 	/* Turn off permissions */
1211 	monitor_permit(mon_dispatch, MONITOR_REQ_SESSKEY, 0);
1212 
1213 	if ((p = BN_new()) == NULL)
1214 		fatal("%s: BN_new", __func__);
1215 
1216 	buffer_get_bignum2(m, p);
1217 
1218 	rsafail = ssh1_session_key(p);
1219 
1220 	buffer_clear(m);
1221 	buffer_put_int(m, rsafail);
1222 	buffer_put_bignum2(m, p);
1223 
1224 	BN_clear_free(p);
1225 
1226 	mm_request_send(sock, MONITOR_ANS_SESSKEY, m);
1227 
1228 	/* Turn on permissions for sessid passing */
1229 	monitor_permit(mon_dispatch, MONITOR_REQ_SESSID, 1);
1230 
1231 	return (0);
1232 }
1233 
1234 int
1235 mm_answer_sessid(int sock, Buffer *m)
1236 {
1237 	int i;
1238 
1239 	debug3("%s entering", __func__);
1240 
1241 	if (buffer_len(m) != 16)
1242 		fatal("%s: bad ssh1 session id", __func__);
1243 	for (i = 0; i < 16; i++)
1244 		session_id[i] = buffer_get_char(m);
1245 
1246 	/* Turn on permissions for getpwnam */
1247 	monitor_permit(mon_dispatch, MONITOR_REQ_PWNAM, 1);
1248 
1249 	return (0);
1250 }
1251 
1252 int
1253 mm_answer_rsa_keyallowed(int sock, Buffer *m)
1254 {
1255 	BIGNUM *client_n;
1256 	Key *key = NULL;
1257 	u_char *blob = NULL;
1258 	u_int blen = 0;
1259 	int allowed = 0;
1260 
1261 	debug3("%s entering", __func__);
1262 
1263 	auth_method = "rsa";
1264 	if (options.rsa_authentication && authctxt->valid) {
1265 		if ((client_n = BN_new()) == NULL)
1266 			fatal("%s: BN_new", __func__);
1267 		buffer_get_bignum2(m, client_n);
1268 		allowed = auth_rsa_key_allowed(authctxt->pw, client_n, &key);
1269 		BN_clear_free(client_n);
1270 	}
1271 	buffer_clear(m);
1272 	buffer_put_int(m, allowed);
1273 	buffer_put_int(m, forced_command != NULL);
1274 
1275 	/* clear temporarily storage (used by generate challenge) */
1276 	monitor_reset_key_state();
1277 
1278 	if (allowed && key != NULL) {
1279 		key->type = KEY_RSA;	/* cheat for key_to_blob */
1280 		if (key_to_blob(key, &blob, &blen) == 0)
1281 			fatal("%s: key_to_blob failed", __func__);
1282 		buffer_put_string(m, blob, blen);
1283 
1284 		/* Save temporarily for comparison in verify */
1285 		key_blob = blob;
1286 		key_bloblen = blen;
1287 		key_blobtype = MM_RSAUSERKEY;
1288 	}
1289 	if (key != NULL)
1290 		key_free(key);
1291 
1292 	mm_request_send(sock, MONITOR_ANS_RSAKEYALLOWED, m);
1293 
1294 	monitor_permit(mon_dispatch, MONITOR_REQ_RSACHALLENGE, allowed);
1295 	monitor_permit(mon_dispatch, MONITOR_REQ_RSARESPONSE, 0);
1296 	return (0);
1297 }
1298 
1299 int
1300 mm_answer_rsa_challenge(int sock, Buffer *m)
1301 {
1302 	Key *key = NULL;
1303 	u_char *blob;
1304 	u_int blen;
1305 
1306 	debug3("%s entering", __func__);
1307 
1308 	if (!authctxt->valid)
1309 		fatal("%s: authctxt not valid", __func__);
1310 	blob = buffer_get_string(m, &blen);
1311 	if (!monitor_allowed_key(blob, blen))
1312 		fatal("%s: bad key, not previously allowed", __func__);
1313 	if (key_blobtype != MM_RSAUSERKEY && key_blobtype != MM_RSAHOSTKEY)
1314 		fatal("%s: key type mismatch", __func__);
1315 	if ((key = key_from_blob(blob, blen)) == NULL)
1316 		fatal("%s: received bad key", __func__);
1317 	if (key->type != KEY_RSA)
1318 		fatal("%s: received bad key type %d", __func__, key->type);
1319 	key->type = KEY_RSA1;
1320 	if (ssh1_challenge)
1321 		BN_clear_free(ssh1_challenge);
1322 	ssh1_challenge = auth_rsa_generate_challenge(key);
1323 
1324 	buffer_clear(m);
1325 	buffer_put_bignum2(m, ssh1_challenge);
1326 
1327 	debug3("%s sending reply", __func__);
1328 	mm_request_send(sock, MONITOR_ANS_RSACHALLENGE, m);
1329 
1330 	monitor_permit(mon_dispatch, MONITOR_REQ_RSARESPONSE, 1);
1331 
1332 	xfree(blob);
1333 	key_free(key);
1334 	return (0);
1335 }
1336 
1337 int
1338 mm_answer_rsa_response(int sock, Buffer *m)
1339 {
1340 	Key *key = NULL;
1341 	u_char *blob, *response;
1342 	u_int blen, len;
1343 	int success;
1344 
1345 	debug3("%s entering", __func__);
1346 
1347 	if (!authctxt->valid)
1348 		fatal("%s: authctxt not valid", __func__);
1349 	if (ssh1_challenge == NULL)
1350 		fatal("%s: no ssh1_challenge", __func__);
1351 
1352 	blob = buffer_get_string(m, &blen);
1353 	if (!monitor_allowed_key(blob, blen))
1354 		fatal("%s: bad key, not previously allowed", __func__);
1355 	if (key_blobtype != MM_RSAUSERKEY && key_blobtype != MM_RSAHOSTKEY)
1356 		fatal("%s: key type mismatch: %d", __func__, key_blobtype);
1357 	if ((key = key_from_blob(blob, blen)) == NULL)
1358 		fatal("%s: received bad key", __func__);
1359 	response = buffer_get_string(m, &len);
1360 	if (len != 16)
1361 		fatal("%s: received bad response to challenge", __func__);
1362 	success = auth_rsa_verify_response(key, ssh1_challenge, response);
1363 
1364 	xfree(blob);
1365 	key_free(key);
1366 	xfree(response);
1367 
1368 	auth_method = key_blobtype == MM_RSAUSERKEY ? "rsa" : "rhosts-rsa";
1369 
1370 	/* reset state */
1371 	BN_clear_free(ssh1_challenge);
1372 	ssh1_challenge = NULL;
1373 	monitor_reset_key_state();
1374 
1375 	buffer_clear(m);
1376 	buffer_put_int(m, success);
1377 	mm_request_send(sock, MONITOR_ANS_RSARESPONSE, m);
1378 
1379 	return (success);
1380 }
1381 
1382 int
1383 mm_answer_term(int sock, Buffer *req)
1384 {
1385 	extern struct monitor *pmonitor;
1386 	int res, status;
1387 
1388 	debug3("%s: tearing down sessions", __func__);
1389 
1390 	/* The child is terminating */
1391 	session_destroy_all(&mm_session_close);
1392 
1393 	while (waitpid(pmonitor->m_pid, &status, 0) == -1)
1394 		if (errno != EINTR)
1395 			exit(1);
1396 
1397 	res = WIFEXITED(status) ? WEXITSTATUS(status) : 1;
1398 
1399 	/* Terminate process */
1400 	exit(res);
1401 }
1402 
1403 void
1404 monitor_apply_keystate(struct monitor *pmonitor)
1405 {
1406 	if (compat20) {
1407 		set_newkeys(MODE_IN);
1408 		set_newkeys(MODE_OUT);
1409 	} else {
1410 		packet_set_protocol_flags(child_state.ssh1protoflags);
1411 		packet_set_encryption_key(child_state.ssh1key,
1412 		    child_state.ssh1keylen, child_state.ssh1cipher);
1413 		xfree(child_state.ssh1key);
1414 	}
1415 
1416 	/* for rc4 and other stateful ciphers */
1417 	packet_set_keycontext(MODE_OUT, child_state.keyout);
1418 	xfree(child_state.keyout);
1419 	packet_set_keycontext(MODE_IN, child_state.keyin);
1420 	xfree(child_state.keyin);
1421 
1422 	if (!compat20) {
1423 		packet_set_iv(MODE_OUT, child_state.ivout);
1424 		xfree(child_state.ivout);
1425 		packet_set_iv(MODE_IN, child_state.ivin);
1426 		xfree(child_state.ivin);
1427 	}
1428 
1429 	memcpy(&incoming_stream, &child_state.incoming,
1430 	    sizeof(incoming_stream));
1431 	memcpy(&outgoing_stream, &child_state.outgoing,
1432 	    sizeof(outgoing_stream));
1433 
1434 	/* Update with new address */
1435 	if (options.compression)
1436 		mm_init_compression(pmonitor->m_zlib);
1437 
1438 	/* Network I/O buffers */
1439 	/* XXX inefficient for large buffers, need: buffer_init_from_string */
1440 	buffer_clear(packet_get_input());
1441 	buffer_append(packet_get_input(), child_state.input, child_state.ilen);
1442 	memset(child_state.input, 0, child_state.ilen);
1443 	xfree(child_state.input);
1444 
1445 	buffer_clear(packet_get_output());
1446 	buffer_append(packet_get_output(), child_state.output,
1447 		      child_state.olen);
1448 	memset(child_state.output, 0, child_state.olen);
1449 	xfree(child_state.output);
1450 
1451 	/* Roaming */
1452 	if (compat20)
1453 		roam_set_bytes(child_state.sent_bytes, child_state.recv_bytes);
1454 }
1455 
1456 static Kex *
1457 mm_get_kex(Buffer *m)
1458 {
1459 	Kex *kex;
1460 	void *blob;
1461 	u_int bloblen;
1462 
1463 	kex = xcalloc(1, sizeof(*kex));
1464 	kex->session_id = buffer_get_string(m, &kex->session_id_len);
1465 	if (session_id2 == NULL ||
1466 	    kex->session_id_len != session_id2_len ||
1467 	    timingsafe_bcmp(kex->session_id, session_id2, session_id2_len) != 0)
1468 		fatal("mm_get_get: internal error: bad session id");
1469 	kex->we_need = buffer_get_int(m);
1470 	kex->kex[KEX_DH_GRP1_SHA1] = kexdh_server;
1471 	kex->kex[KEX_DH_GRP14_SHA1] = kexdh_server;
1472 	kex->kex[KEX_DH_GEX_SHA1] = kexgex_server;
1473 	kex->kex[KEX_DH_GEX_SHA256] = kexgex_server;
1474 	kex->kex[KEX_ECDH_SHA2] = kexecdh_server;
1475 	kex->server = 1;
1476 	kex->hostkey_type = buffer_get_int(m);
1477 	kex->kex_type = buffer_get_int(m);
1478 	blob = buffer_get_string(m, &bloblen);
1479 	buffer_init(&kex->my);
1480 	buffer_append(&kex->my, blob, bloblen);
1481 	xfree(blob);
1482 	blob = buffer_get_string(m, &bloblen);
1483 	buffer_init(&kex->peer);
1484 	buffer_append(&kex->peer, blob, bloblen);
1485 	xfree(blob);
1486 	kex->done = 1;
1487 	kex->flags = buffer_get_int(m);
1488 	kex->client_version_string = buffer_get_string(m, NULL);
1489 	kex->server_version_string = buffer_get_string(m, NULL);
1490 	kex->load_host_public_key=&get_hostkey_public_by_type;
1491 	kex->load_host_private_key=&get_hostkey_private_by_type;
1492 	kex->host_key_index=&get_hostkey_index;
1493 
1494 	return (kex);
1495 }
1496 
1497 /* This function requries careful sanity checking */
1498 
1499 void
1500 mm_get_keystate(struct monitor *pmonitor)
1501 {
1502 	Buffer m;
1503 	u_char *blob, *p;
1504 	u_int bloblen, plen;
1505 	u_int32_t seqnr, packets;
1506 	u_int64_t blocks, bytes;
1507 
1508 	debug3("%s: Waiting for new keys", __func__);
1509 
1510 	buffer_init(&m);
1511 	mm_request_receive_expect(pmonitor->m_sendfd, MONITOR_REQ_KEYEXPORT, &m);
1512 	if (!compat20) {
1513 		child_state.ssh1protoflags = buffer_get_int(&m);
1514 		child_state.ssh1cipher = buffer_get_int(&m);
1515 		child_state.ssh1key = buffer_get_string(&m,
1516 		    &child_state.ssh1keylen);
1517 		child_state.ivout = buffer_get_string(&m,
1518 		    &child_state.ivoutlen);
1519 		child_state.ivin = buffer_get_string(&m, &child_state.ivinlen);
1520 		goto skip;
1521 	} else {
1522 		/* Get the Kex for rekeying */
1523 		*pmonitor->m_pkex = mm_get_kex(&m);
1524 	}
1525 
1526 	blob = buffer_get_string(&m, &bloblen);
1527 	current_keys[MODE_OUT] = mm_newkeys_from_blob(blob, bloblen);
1528 	xfree(blob);
1529 
1530 	debug3("%s: Waiting for second key", __func__);
1531 	blob = buffer_get_string(&m, &bloblen);
1532 	current_keys[MODE_IN] = mm_newkeys_from_blob(blob, bloblen);
1533 	xfree(blob);
1534 
1535 	/* Now get sequence numbers for the packets */
1536 	seqnr = buffer_get_int(&m);
1537 	blocks = buffer_get_int64(&m);
1538 	packets = buffer_get_int(&m);
1539 	bytes = buffer_get_int64(&m);
1540 	packet_set_state(MODE_OUT, seqnr, blocks, packets, bytes);
1541 	seqnr = buffer_get_int(&m);
1542 	blocks = buffer_get_int64(&m);
1543 	packets = buffer_get_int(&m);
1544 	bytes = buffer_get_int64(&m);
1545 	packet_set_state(MODE_IN, seqnr, blocks, packets, bytes);
1546 
1547  skip:
1548 	/* Get the key context */
1549 	child_state.keyout = buffer_get_string(&m, &child_state.keyoutlen);
1550 	child_state.keyin  = buffer_get_string(&m, &child_state.keyinlen);
1551 
1552 	debug3("%s: Getting compression state", __func__);
1553 	/* Get compression state */
1554 	p = buffer_get_string(&m, &plen);
1555 	if (plen != sizeof(child_state.outgoing))
1556 		fatal("%s: bad request size", __func__);
1557 	memcpy(&child_state.outgoing, p, sizeof(child_state.outgoing));
1558 	xfree(p);
1559 
1560 	p = buffer_get_string(&m, &plen);
1561 	if (plen != sizeof(child_state.incoming))
1562 		fatal("%s: bad request size", __func__);
1563 	memcpy(&child_state.incoming, p, sizeof(child_state.incoming));
1564 	xfree(p);
1565 
1566 	/* Network I/O buffers */
1567 	debug3("%s: Getting Network I/O buffers", __func__);
1568 	child_state.input = buffer_get_string(&m, &child_state.ilen);
1569 	child_state.output = buffer_get_string(&m, &child_state.olen);
1570 
1571 	/* Roaming */
1572 	if (compat20) {
1573 		child_state.sent_bytes = buffer_get_int64(&m);
1574 		child_state.recv_bytes = buffer_get_int64(&m);
1575 	}
1576 
1577 	buffer_free(&m);
1578 }
1579 
1580 
1581 /* Allocation functions for zlib */
1582 void *
1583 mm_zalloc(struct mm_master *mm, u_int ncount, u_int size)
1584 {
1585 	size_t len = (size_t) size * ncount;
1586 	void *address;
1587 
1588 	if (len == 0 || ncount > SIZE_T_MAX / size)
1589 		fatal("%s: mm_zalloc(%u, %u)", __func__, ncount, size);
1590 
1591 	address = mm_malloc(mm, len);
1592 
1593 	return (address);
1594 }
1595 
1596 void
1597 mm_zfree(struct mm_master *mm, void *address)
1598 {
1599 	mm_free(mm, address);
1600 }
1601 
1602 void
1603 mm_init_compression(struct mm_master *mm)
1604 {
1605 	outgoing_stream.zalloc = (alloc_func)mm_zalloc;
1606 	outgoing_stream.zfree = (free_func)mm_zfree;
1607 	outgoing_stream.opaque = mm;
1608 
1609 	incoming_stream.zalloc = (alloc_func)mm_zalloc;
1610 	incoming_stream.zfree = (free_func)mm_zfree;
1611 	incoming_stream.opaque = mm;
1612 }
1613 
1614 /* XXX */
1615 
1616 #define FD_CLOSEONEXEC(x) do { \
1617 	if (fcntl(x, F_SETFD, FD_CLOEXEC) == -1) \
1618 		fatal("fcntl(%d, F_SETFD)", x); \
1619 } while (0)
1620 
1621 static void
1622 monitor_openfds(struct monitor *mon, int do_logfds)
1623 {
1624 	int pair[2];
1625 
1626 	if (socketpair(AF_UNIX, SOCK_STREAM, 0, pair) == -1)
1627 		fatal("%s: socketpair: %s", __func__, strerror(errno));
1628 	FD_CLOSEONEXEC(pair[0]);
1629 	FD_CLOSEONEXEC(pair[1]);
1630 	mon->m_recvfd = pair[0];
1631 	mon->m_sendfd = pair[1];
1632 
1633 	if (do_logfds) {
1634 		if (pipe(pair) == -1)
1635 			fatal("%s: pipe: %s", __func__, strerror(errno));
1636 		FD_CLOSEONEXEC(pair[0]);
1637 		FD_CLOSEONEXEC(pair[1]);
1638 		mon->m_log_recvfd = pair[0];
1639 		mon->m_log_sendfd = pair[1];
1640 	} else
1641 		mon->m_log_recvfd = mon->m_log_sendfd = -1;
1642 }
1643 
1644 #define MM_MEMSIZE	65536
1645 
1646 struct monitor *
1647 monitor_init(void)
1648 {
1649 	struct monitor *mon;
1650 
1651 	mon = xcalloc(1, sizeof(*mon));
1652 
1653 	monitor_openfds(mon, 1);
1654 
1655 	/* Used to share zlib space across processes */
1656 	if (options.compression) {
1657 		mon->m_zback = mm_create(NULL, MM_MEMSIZE);
1658 		mon->m_zlib = mm_create(mon->m_zback, 20 * MM_MEMSIZE);
1659 
1660 		/* Compression needs to share state across borders */
1661 		mm_init_compression(mon->m_zlib);
1662 	}
1663 
1664 	return mon;
1665 }
1666 
1667 void
1668 monitor_reinit(struct monitor *mon)
1669 {
1670 	monitor_openfds(mon, 0);
1671 }
1672 
1673 #ifdef GSSAPI
1674 int
1675 mm_answer_gss_setup_ctx(int sock, Buffer *m)
1676 {
1677 	gss_OID_desc goid;
1678 	OM_uint32 major;
1679 	u_int len;
1680 
1681 	goid.elements = buffer_get_string(m, &len);
1682 	goid.length = len;
1683 
1684 	major = ssh_gssapi_server_ctx(&gsscontext, &goid);
1685 
1686 	xfree(goid.elements);
1687 
1688 	buffer_clear(m);
1689 	buffer_put_int(m, major);
1690 
1691 	mm_request_send(sock, MONITOR_ANS_GSSSETUP, m);
1692 
1693 	/* Now we have a context, enable the step */
1694 	monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 1);
1695 
1696 	return (0);
1697 }
1698 
1699 int
1700 mm_answer_gss_accept_ctx(int sock, Buffer *m)
1701 {
1702 	gss_buffer_desc in;
1703 	gss_buffer_desc out = GSS_C_EMPTY_BUFFER;
1704 	OM_uint32 major, minor;
1705 	OM_uint32 flags = 0; /* GSI needs this */
1706 	u_int len;
1707 
1708 	in.value = buffer_get_string(m, &len);
1709 	in.length = len;
1710 	major = ssh_gssapi_accept_ctx(gsscontext, &in, &out, &flags);
1711 	xfree(in.value);
1712 
1713 	buffer_clear(m);
1714 	buffer_put_int(m, major);
1715 	buffer_put_string(m, out.value, out.length);
1716 	buffer_put_int(m, flags);
1717 	mm_request_send(sock, MONITOR_ANS_GSSSTEP, m);
1718 
1719 	gss_release_buffer(&minor, &out);
1720 
1721 	if (major == GSS_S_COMPLETE) {
1722 		monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 0);
1723 		monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
1724 		monitor_permit(mon_dispatch, MONITOR_REQ_GSSCHECKMIC, 1);
1725 	}
1726 	return (0);
1727 }
1728 
1729 int
1730 mm_answer_gss_checkmic(int sock, Buffer *m)
1731 {
1732 	gss_buffer_desc gssbuf, mic;
1733 	OM_uint32 ret;
1734 	u_int len;
1735 
1736 	gssbuf.value = buffer_get_string(m, &len);
1737 	gssbuf.length = len;
1738 	mic.value = buffer_get_string(m, &len);
1739 	mic.length = len;
1740 
1741 	ret = ssh_gssapi_checkmic(gsscontext, &gssbuf, &mic);
1742 
1743 	xfree(gssbuf.value);
1744 	xfree(mic.value);
1745 
1746 	buffer_clear(m);
1747 	buffer_put_int(m, ret);
1748 
1749 	mm_request_send(sock, MONITOR_ANS_GSSCHECKMIC, m);
1750 
1751 	if (!GSS_ERROR(ret))
1752 		monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
1753 
1754 	return (0);
1755 }
1756 
1757 int
1758 mm_answer_gss_userok(int sock, Buffer *m)
1759 {
1760 	int authenticated;
1761 
1762 	authenticated = authctxt->valid && ssh_gssapi_userok(authctxt->user);
1763 
1764 	buffer_clear(m);
1765 	buffer_put_int(m, authenticated);
1766 
1767 	debug3("%s: sending result %d", __func__, authenticated);
1768 	mm_request_send(sock, MONITOR_ANS_GSSUSEROK, m);
1769 
1770 	auth_method = "gssapi-with-mic";
1771 
1772 	/* Monitor loop will terminate if authenticated */
1773 	return (authenticated);
1774 }
1775 #endif /* GSSAPI */
1776 
1777 #ifdef JPAKE
1778 int
1779 mm_answer_jpake_step1(int sock, Buffer *m)
1780 {
1781 	struct jpake_ctx *pctx;
1782 	u_char *x3_proof, *x4_proof;
1783 	u_int x3_proof_len, x4_proof_len;
1784 
1785 	if (!options.zero_knowledge_password_authentication)
1786 		fatal("zero_knowledge_password_authentication disabled");
1787 
1788 	if (authctxt->jpake_ctx != NULL)
1789 		fatal("%s: authctxt->jpake_ctx already set (%p)",
1790 		    __func__, authctxt->jpake_ctx);
1791 	authctxt->jpake_ctx = pctx = jpake_new();
1792 
1793 	jpake_step1(pctx->grp,
1794 	    &pctx->server_id, &pctx->server_id_len,
1795 	    &pctx->x3, &pctx->x4, &pctx->g_x3, &pctx->g_x4,
1796 	    &x3_proof, &x3_proof_len,
1797 	    &x4_proof, &x4_proof_len);
1798 
1799 	JPAKE_DEBUG_CTX((pctx, "step1 done in %s", __func__));
1800 
1801 	buffer_clear(m);
1802 
1803 	buffer_put_string(m, pctx->server_id, pctx->server_id_len);
1804 	buffer_put_bignum2(m, pctx->g_x3);
1805 	buffer_put_bignum2(m, pctx->g_x4);
1806 	buffer_put_string(m, x3_proof, x3_proof_len);
1807 	buffer_put_string(m, x4_proof, x4_proof_len);
1808 
1809 	debug3("%s: sending step1", __func__);
1810 	mm_request_send(sock, MONITOR_ANS_JPAKE_STEP1, m);
1811 
1812 	bzero(x3_proof, x3_proof_len);
1813 	bzero(x4_proof, x4_proof_len);
1814 	xfree(x3_proof);
1815 	xfree(x4_proof);
1816 
1817 	monitor_permit(mon_dispatch, MONITOR_REQ_JPAKE_GET_PWDATA, 1);
1818 	monitor_permit(mon_dispatch, MONITOR_REQ_JPAKE_STEP1, 0);
1819 
1820 	return 0;
1821 }
1822 
1823 int
1824 mm_answer_jpake_get_pwdata(int sock, Buffer *m)
1825 {
1826 	struct jpake_ctx *pctx = authctxt->jpake_ctx;
1827 	char *hash_scheme, *salt;
1828 
1829 	if (pctx == NULL)
1830 		fatal("%s: pctx == NULL", __func__);
1831 
1832 	auth2_jpake_get_pwdata(authctxt, &pctx->s, &hash_scheme, &salt);
1833 
1834 	buffer_clear(m);
1835 	/* pctx->s is sensitive, not returned to slave */
1836 	buffer_put_cstring(m, hash_scheme);
1837 	buffer_put_cstring(m, salt);
1838 
1839 	debug3("%s: sending pwdata", __func__);
1840 	mm_request_send(sock, MONITOR_ANS_JPAKE_GET_PWDATA, m);
1841 
1842 	bzero(hash_scheme, strlen(hash_scheme));
1843 	bzero(salt, strlen(salt));
1844 	xfree(hash_scheme);
1845 	xfree(salt);
1846 
1847 	monitor_permit(mon_dispatch, MONITOR_REQ_JPAKE_STEP2, 1);
1848 
1849 	return 0;
1850 }
1851 
1852 int
1853 mm_answer_jpake_step2(int sock, Buffer *m)
1854 {
1855 	struct jpake_ctx *pctx = authctxt->jpake_ctx;
1856 	u_char *x1_proof, *x2_proof, *x4_s_proof;
1857 	u_int x1_proof_len, x2_proof_len, x4_s_proof_len;
1858 
1859 	if (pctx == NULL)
1860 		fatal("%s: pctx == NULL", __func__);
1861 
1862 	if ((pctx->g_x1 = BN_new()) == NULL ||
1863 	    (pctx->g_x2 = BN_new()) == NULL)
1864 		fatal("%s: BN_new", __func__);
1865 	buffer_get_bignum2(m, pctx->g_x1);
1866 	buffer_get_bignum2(m, pctx->g_x2);
1867 	pctx->client_id = buffer_get_string(m, &pctx->client_id_len);
1868 	x1_proof = buffer_get_string(m, &x1_proof_len);
1869 	x2_proof = buffer_get_string(m, &x2_proof_len);
1870 
1871 	jpake_step2(pctx->grp, pctx->s, pctx->g_x3,
1872 	    pctx->g_x1, pctx->g_x2, pctx->x4,
1873 	    pctx->client_id, pctx->client_id_len,
1874 	    pctx->server_id, pctx->server_id_len,
1875 	    x1_proof, x1_proof_len,
1876 	    x2_proof, x2_proof_len,
1877 	    &pctx->b,
1878 	    &x4_s_proof, &x4_s_proof_len);
1879 
1880 	JPAKE_DEBUG_CTX((pctx, "step2 done in %s", __func__));
1881 
1882 	bzero(x1_proof, x1_proof_len);
1883 	bzero(x2_proof, x2_proof_len);
1884 	xfree(x1_proof);
1885 	xfree(x2_proof);
1886 
1887 	buffer_clear(m);
1888 
1889 	buffer_put_bignum2(m, pctx->b);
1890 	buffer_put_string(m, x4_s_proof, x4_s_proof_len);
1891 
1892 	debug3("%s: sending step2", __func__);
1893 	mm_request_send(sock, MONITOR_ANS_JPAKE_STEP2, m);
1894 
1895 	bzero(x4_s_proof, x4_s_proof_len);
1896 	xfree(x4_s_proof);
1897 
1898 	monitor_permit(mon_dispatch, MONITOR_REQ_JPAKE_KEY_CONFIRM, 1);
1899 
1900 	return 0;
1901 }
1902 
1903 int
1904 mm_answer_jpake_key_confirm(int sock, Buffer *m)
1905 {
1906 	struct jpake_ctx *pctx = authctxt->jpake_ctx;
1907 	u_char *x2_s_proof;
1908 	u_int x2_s_proof_len;
1909 
1910 	if (pctx == NULL)
1911 		fatal("%s: pctx == NULL", __func__);
1912 
1913 	if ((pctx->a = BN_new()) == NULL)
1914 		fatal("%s: BN_new", __func__);
1915 	buffer_get_bignum2(m, pctx->a);
1916 	x2_s_proof = buffer_get_string(m, &x2_s_proof_len);
1917 
1918 	jpake_key_confirm(pctx->grp, pctx->s, pctx->a,
1919 	    pctx->x4, pctx->g_x3, pctx->g_x4, pctx->g_x1, pctx->g_x2,
1920 	    pctx->server_id, pctx->server_id_len,
1921 	    pctx->client_id, pctx->client_id_len,
1922 	    session_id2, session_id2_len,
1923 	    x2_s_proof, x2_s_proof_len,
1924 	    &pctx->k,
1925 	    &pctx->h_k_sid_sessid, &pctx->h_k_sid_sessid_len);
1926 
1927 	JPAKE_DEBUG_CTX((pctx, "key_confirm done in %s", __func__));
1928 
1929 	bzero(x2_s_proof, x2_s_proof_len);
1930 	buffer_clear(m);
1931 
1932 	/* pctx->k is sensitive, not sent */
1933 	buffer_put_string(m, pctx->h_k_sid_sessid, pctx->h_k_sid_sessid_len);
1934 
1935 	debug3("%s: sending confirmation hash", __func__);
1936 	mm_request_send(sock, MONITOR_ANS_JPAKE_KEY_CONFIRM, m);
1937 
1938 	monitor_permit(mon_dispatch, MONITOR_REQ_JPAKE_CHECK_CONFIRM, 1);
1939 
1940 	return 0;
1941 }
1942 
1943 int
1944 mm_answer_jpake_check_confirm(int sock, Buffer *m)
1945 {
1946 	int authenticated = 0;
1947 	u_char *peer_confirm_hash;
1948 	u_int peer_confirm_hash_len;
1949 	struct jpake_ctx *pctx = authctxt->jpake_ctx;
1950 
1951 	if (pctx == NULL)
1952 		fatal("%s: pctx == NULL", __func__);
1953 
1954 	peer_confirm_hash = buffer_get_string(m, &peer_confirm_hash_len);
1955 
1956 	authenticated = jpake_check_confirm(pctx->k,
1957 	    pctx->client_id, pctx->client_id_len,
1958 	    session_id2, session_id2_len,
1959 	    peer_confirm_hash, peer_confirm_hash_len) && authctxt->valid;
1960 
1961 	JPAKE_DEBUG_CTX((pctx, "check_confirm done in %s", __func__));
1962 
1963 	bzero(peer_confirm_hash, peer_confirm_hash_len);
1964 	xfree(peer_confirm_hash);
1965 
1966 	buffer_clear(m);
1967 	buffer_put_int(m, authenticated);
1968 
1969 	debug3("%s: sending result %d", __func__, authenticated);
1970 	mm_request_send(sock, MONITOR_ANS_JPAKE_CHECK_CONFIRM, m);
1971 
1972 	monitor_permit(mon_dispatch, MONITOR_REQ_JPAKE_STEP1, 1);
1973 
1974 	auth_method = "jpake-01@openssh.com";
1975 	return authenticated;
1976 }
1977 
1978 #endif /* JPAKE */
1979