1/* $OpenBSD: monitor_wrap.c,v 1.136 2024/06/19 23:24:47 djm Exp $ */
2/*
3 * Copyright 2002 Niels Provos <provos@citi.umich.edu>
4 * Copyright 2002 Markus Friedl <markus@openbsd.org>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26 */
27
28#include <sys/types.h>
29#include <sys/uio.h>
30#include <sys/queue.h>
31#include <sys/wait.h>
32
33#include <errno.h>
34#include <pwd.h>
35#include <signal.h>
36#include <stdio.h>
37#include <string.h>
38#include <stdarg.h>
39#include <unistd.h>
40
41#ifdef WITH_OPENSSL
42#include <openssl/bn.h>
43#include <openssl/dh.h>
44#endif
45
46#include "xmalloc.h"
47#include "ssh.h"
48#ifdef WITH_OPENSSL
49#include "dh.h"
50#endif
51#include "sshbuf.h"
52#include "sshkey.h"
53#include "cipher.h"
54#include "kex.h"
55#include "hostfile.h"
56#include "auth.h"
57#include "auth-options.h"
58#include "packet.h"
59#include "mac.h"
60#include "log.h"
61#include "monitor.h"
62#ifdef GSSAPI
63#include "ssh-gss.h"
64#endif
65#include "atomicio.h"
66#include "monitor_fdpass.h"
67#include "misc.h"
68
69#include "channels.h"
70#include "session.h"
71#include "servconf.h"
72#include "monitor_wrap.h"
73#include "srclimit.h"
74
75#include "ssherr.h"
76
77/* Imports */
78extern struct monitor *pmonitor;
79extern struct sshbuf *loginmsg;
80extern ServerOptions options;
81
82void
83mm_log_handler(LogLevel level, int forced, const char *msg, void *ctx)
84{
85	struct sshbuf *log_msg;
86	struct monitor *mon = (struct monitor *)ctx;
87	int r;
88	size_t len;
89
90	if (mon->m_log_sendfd == -1)
91		fatal_f("no log channel");
92
93	if ((log_msg = sshbuf_new()) == NULL)
94		fatal_f("sshbuf_new failed");
95
96	if ((r = sshbuf_put_u32(log_msg, 0)) != 0 || /* length; filled below */
97	    (r = sshbuf_put_u32(log_msg, level)) != 0 ||
98	    (r = sshbuf_put_u32(log_msg, forced)) != 0 ||
99	    (r = sshbuf_put_cstring(log_msg, msg)) != 0)
100		fatal_fr(r, "assemble");
101	if ((len = sshbuf_len(log_msg)) < 4 || len > 0xffffffff)
102		fatal_f("bad length %zu", len);
103	POKE_U32(sshbuf_mutable_ptr(log_msg), len - 4);
104	if (atomicio(vwrite, mon->m_log_sendfd,
105	    sshbuf_mutable_ptr(log_msg), len) != len)
106		fatal_f("write: %s", strerror(errno));
107	sshbuf_free(log_msg);
108}
109
110int
111mm_is_monitor(void)
112{
113	/*
114	 * m_pid is only set in the privileged part, and
115	 * points to the unprivileged child.
116	 */
117	return (pmonitor && pmonitor->m_pid > 0);
118}
119
120static void
121mm_reap(void)
122{
123	int status = -1;
124
125	if (!mm_is_monitor())
126		return;
127	while (waitpid(pmonitor->m_pid, &status, 0) == -1) {
128		if (errno == EINTR)
129			continue;
130		pmonitor->m_pid = -1;
131		fatal_f("waitpid: %s", strerror(errno));
132	}
133	if (WIFEXITED(status)) {
134		if (WEXITSTATUS(status) != 0) {
135			debug_f("preauth child exited with status %d",
136			    WEXITSTATUS(status));
137			cleanup_exit(255);
138		}
139	} else if (WIFSIGNALED(status)) {
140		error_f("preauth child terminated by signal %d",
141		    WTERMSIG(status));
142		cleanup_exit(signal_is_crash(WTERMSIG(status)) ?
143		    EXIT_CHILD_CRASH : 255);
144	} else {
145		error_f("preauth child terminated abnormally (status=0x%x)",
146		    status);
147		cleanup_exit(EXIT_CHILD_CRASH);
148	}
149}
150
151void
152mm_request_send(int sock, enum monitor_reqtype type, struct sshbuf *m)
153{
154	size_t mlen = sshbuf_len(m);
155	u_char buf[5];
156
157	debug3_f("entering, type %d", type);
158
159	if (mlen >= 0xffffffff)
160		fatal_f("bad length %zu", mlen);
161	POKE_U32(buf, mlen + 1);
162	buf[4] = (u_char) type;		/* 1st byte of payload is mesg-type */
163	if (atomicio(vwrite, sock, buf, sizeof(buf)) != sizeof(buf) ||
164	    atomicio(vwrite, sock, sshbuf_mutable_ptr(m), mlen) != mlen) {
165		if (errno == EPIPE) {
166			debug3_f("monitor fd closed");
167			mm_reap();
168			cleanup_exit(255);
169		}
170		fatal_f("write: %s", strerror(errno));
171	}
172}
173
174void
175mm_request_receive(int sock, struct sshbuf *m)
176{
177	u_char buf[4], *p = NULL;
178	u_int msg_len;
179	int oerrno, r;
180
181	debug3_f("entering");
182
183	if (atomicio(read, sock, buf, sizeof(buf)) != sizeof(buf)) {
184		if (errno == EPIPE) {
185			debug3_f("monitor fd closed");
186			mm_reap();
187			cleanup_exit(255);
188		}
189		fatal_f("read: %s", strerror(errno));
190	}
191	msg_len = PEEK_U32(buf);
192	if (msg_len > 256 * 1024)
193		fatal_f("read: bad msg_len %d", msg_len);
194	sshbuf_reset(m);
195	if ((r = sshbuf_reserve(m, msg_len, &p)) != 0)
196		fatal_fr(r, "reserve");
197	if (atomicio(read, sock, p, msg_len) != msg_len) {
198		oerrno = errno;
199		error_f("read: %s", strerror(errno));
200		if (oerrno == EPIPE)
201			mm_reap();
202		cleanup_exit(255);
203	}
204}
205
206void
207mm_request_receive_expect(int sock, enum monitor_reqtype type, struct sshbuf *m)
208{
209	u_char rtype;
210	int r;
211
212	debug3_f("entering, type %d", type);
213
214	mm_request_receive(sock, m);
215	if ((r = sshbuf_get_u8(m, &rtype)) != 0)
216		fatal_fr(r, "parse");
217	if (rtype != type)
218		fatal_f("read: rtype %d != type %d", rtype, type);
219}
220
221#ifdef WITH_OPENSSL
222DH *
223mm_choose_dh(int min, int nbits, int max)
224{
225	BIGNUM *p, *g;
226	int r;
227	u_char success = 0;
228	struct sshbuf *m;
229
230	if ((m = sshbuf_new()) == NULL)
231		fatal_f("sshbuf_new failed");
232	if ((r = sshbuf_put_u32(m, min)) != 0 ||
233	    (r = sshbuf_put_u32(m, nbits)) != 0 ||
234	    (r = sshbuf_put_u32(m, max)) != 0)
235		fatal_fr(r, "assemble");
236
237	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_MODULI, m);
238
239	debug3_f("waiting for MONITOR_ANS_MODULI");
240	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_MODULI, m);
241
242	if ((r = sshbuf_get_u8(m, &success)) != 0)
243		fatal_fr(r, "parse success");
244	if (success == 0)
245		fatal_f("MONITOR_ANS_MODULI failed");
246
247	if ((r = sshbuf_get_bignum2(m, &p)) != 0 ||
248	    (r = sshbuf_get_bignum2(m, &g)) != 0)
249		fatal_fr(r, "parse group");
250
251	debug3_f("remaining %zu", sshbuf_len(m));
252	sshbuf_free(m);
253
254	return (dh_new_group(g, p));
255}
256#endif
257
258int
259mm_sshkey_sign(struct ssh *ssh, struct sshkey *key, u_char **sigp, size_t *lenp,
260    const u_char *data, size_t datalen, const char *hostkey_alg,
261    const char *sk_provider, const char *sk_pin, u_int compat)
262{
263	struct kex *kex = *pmonitor->m_pkex;
264	struct sshbuf *m;
265	u_int ndx = kex->host_key_index(key, 0, ssh);
266	int r;
267
268	debug3_f("entering");
269	if ((m = sshbuf_new()) == NULL)
270		fatal_f("sshbuf_new failed");
271	if ((r = sshbuf_put_u32(m, ndx)) != 0 ||
272	    (r = sshbuf_put_string(m, data, datalen)) != 0 ||
273	    (r = sshbuf_put_cstring(m, hostkey_alg)) != 0 ||
274	    (r = sshbuf_put_u32(m, compat)) != 0)
275		fatal_fr(r, "assemble");
276
277	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SIGN, m);
278
279	debug3_f("waiting for MONITOR_ANS_SIGN");
280	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SIGN, m);
281	if ((r = sshbuf_get_string(m, sigp, lenp)) != 0)
282		fatal_fr(r, "parse");
283	sshbuf_free(m);
284
285	return (0);
286}
287
288void
289mm_decode_activate_server_options(struct ssh *ssh, struct sshbuf *m)
290{
291	const u_char *p;
292	size_t len;
293	u_int i;
294	ServerOptions *newopts;
295	int r;
296
297	if ((r = sshbuf_get_string_direct(m, &p, &len)) != 0)
298		fatal_fr(r, "parse opts");
299	if (len != sizeof(*newopts))
300		fatal_f("option block size mismatch");
301	newopts = xcalloc(sizeof(*newopts), 1);
302	memcpy(newopts, p, sizeof(*newopts));
303
304#define M_CP_STROPT(x) do { \
305		if (newopts->x != NULL && \
306		    (r = sshbuf_get_cstring(m, &newopts->x, NULL)) != 0) \
307			fatal_fr(r, "parse %s", #x); \
308	} while (0)
309#define M_CP_STRARRAYOPT(x, nx) do { \
310		newopts->x = newopts->nx == 0 ? \
311		    NULL : xcalloc(newopts->nx, sizeof(*newopts->x)); \
312		for (i = 0; i < newopts->nx; i++) { \
313			if ((r = sshbuf_get_cstring(m, \
314			    &newopts->x[i], NULL)) != 0) \
315				fatal_fr(r, "parse %s", #x); \
316		} \
317	} while (0)
318	/* See comment in servconf.h */
319	COPY_MATCH_STRING_OPTS();
320#undef M_CP_STROPT
321#undef M_CP_STRARRAYOPT
322
323	copy_set_server_options(&options, newopts, 1);
324	log_change_level(options.log_level);
325	log_verbose_reset();
326	for (i = 0; i < options.num_log_verbose; i++)
327		log_verbose_add(options.log_verbose[i]);
328	free(newopts);
329}
330
331#define GETPW(b, id) \
332	do { \
333		if ((r = sshbuf_get_string_direct(b, &p, &len)) != 0) \
334			fatal_fr(r, "parse pw %s", #id); \
335		if (len != sizeof(pw->id)) \
336			fatal_fr(r, "bad length for %s", #id); \
337		memcpy(&pw->id, p, len); \
338	} while (0)
339
340struct passwd *
341mm_getpwnamallow(struct ssh *ssh, const char *username)
342{
343	struct sshbuf *m;
344	struct passwd *pw;
345	size_t len;
346	int r;
347	u_char ok;
348	const u_char *p;
349
350	debug3_f("entering");
351
352	if ((m = sshbuf_new()) == NULL)
353		fatal_f("sshbuf_new failed");
354	if ((r = sshbuf_put_cstring(m, username)) != 0)
355		fatal_fr(r, "assemble");
356
357	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PWNAM, m);
358
359	debug3_f("waiting for MONITOR_ANS_PWNAM");
360	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PWNAM, m);
361
362	if ((r = sshbuf_get_u8(m, &ok)) != 0)
363		fatal_fr(r, "parse success");
364	if (ok == 0) {
365		pw = NULL;
366		goto out;
367	}
368
369	pw = xcalloc(sizeof(*pw), 1);
370	GETPW(m, pw_uid);
371	GETPW(m, pw_gid);
372	GETPW(m, pw_change);
373	GETPW(m, pw_expire);
374	if ((r = sshbuf_get_cstring(m, &pw->pw_name, NULL)) != 0 ||
375	    (r = sshbuf_get_cstring(m, &pw->pw_passwd, NULL)) != 0 ||
376	    (r = sshbuf_get_cstring(m, &pw->pw_gecos, NULL)) != 0 ||
377	    (r = sshbuf_get_cstring(m, &pw->pw_class, NULL)) != 0 ||
378	    (r = sshbuf_get_cstring(m, &pw->pw_dir, NULL)) != 0 ||
379	    (r = sshbuf_get_cstring(m, &pw->pw_shell, NULL)) != 0)
380		fatal_fr(r, "parse pw");
381
382out:
383	/* copy options block as a Match directive may have changed some */
384	mm_decode_activate_server_options(ssh, m);
385	server_process_permitopen(ssh);
386	server_process_channel_timeouts(ssh);
387	kex_set_server_sig_algs(ssh, options.pubkey_accepted_algos);
388	sshbuf_free(m);
389
390	return (pw);
391}
392
393char *
394mm_auth2_read_banner(void)
395{
396	struct sshbuf *m;
397	char *banner;
398	int r;
399
400	debug3_f("entering");
401
402	if ((m = sshbuf_new()) == NULL)
403		fatal_f("sshbuf_new failed");
404	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTH2_READ_BANNER, m);
405	sshbuf_reset(m);
406
407	mm_request_receive_expect(pmonitor->m_recvfd,
408	    MONITOR_ANS_AUTH2_READ_BANNER, m);
409	if ((r = sshbuf_get_cstring(m, &banner, NULL)) != 0)
410		fatal_fr(r, "parse");
411	sshbuf_free(m);
412
413	/* treat empty banner as missing banner */
414	if (strlen(banner) == 0) {
415		free(banner);
416		banner = NULL;
417	}
418	return (banner);
419}
420
421/* Inform the privileged process about service and style */
422
423void
424mm_inform_authserv(char *service, char *style)
425{
426	struct sshbuf *m;
427	int r;
428
429	debug3_f("entering");
430
431	if ((m = sshbuf_new()) == NULL)
432		fatal_f("sshbuf_new failed");
433	if ((r = sshbuf_put_cstring(m, service)) != 0 ||
434	    (r = sshbuf_put_cstring(m, style ? style : "")) != 0)
435		fatal_fr(r, "assemble");
436
437	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHSERV, m);
438
439	sshbuf_free(m);
440}
441
442/* Do the password authentication */
443int
444mm_auth_password(struct ssh *ssh, char *password)
445{
446	struct sshbuf *m;
447	int r, authenticated = 0;
448
449	debug3_f("entering");
450
451	if ((m = sshbuf_new()) == NULL)
452		fatal_f("sshbuf_new failed");
453	if ((r = sshbuf_put_cstring(m, password)) != 0)
454		fatal_fr(r, "assemble");
455	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHPASSWORD, m);
456
457	debug3_f("waiting for MONITOR_ANS_AUTHPASSWORD");
458	mm_request_receive_expect(pmonitor->m_recvfd,
459	    MONITOR_ANS_AUTHPASSWORD, m);
460
461	if ((r = sshbuf_get_u32(m, &authenticated)) != 0)
462		fatal_fr(r, "parse");
463
464	sshbuf_free(m);
465
466	debug3_f("user %sauthenticated", authenticated ? "" : "not ");
467	return (authenticated);
468}
469
470int
471mm_user_key_allowed(struct ssh *ssh, struct passwd *pw, struct sshkey *key,
472    int pubkey_auth_attempt, struct sshauthopt **authoptp)
473{
474	return (mm_key_allowed(MM_USERKEY, NULL, NULL, key,
475	    pubkey_auth_attempt, authoptp));
476}
477
478int
479mm_hostbased_key_allowed(struct ssh *ssh, struct passwd *pw,
480    const char *user, const char *host, struct sshkey *key)
481{
482	return (mm_key_allowed(MM_HOSTKEY, user, host, key, 0, NULL));
483}
484
485int
486mm_key_allowed(enum mm_keytype type, const char *user, const char *host,
487    struct sshkey *key, int pubkey_auth_attempt, struct sshauthopt **authoptp)
488{
489	struct sshbuf *m;
490	int r, allowed = 0;
491	struct sshauthopt *opts = NULL;
492
493	debug3_f("entering");
494
495	if (authoptp != NULL)
496		*authoptp = NULL;
497
498	if ((m = sshbuf_new()) == NULL)
499		fatal_f("sshbuf_new failed");
500	if ((r = sshbuf_put_u32(m, type)) != 0 ||
501	    (r = sshbuf_put_cstring(m, user ? user : "")) != 0 ||
502	    (r = sshbuf_put_cstring(m, host ? host : "")) != 0 ||
503	    (r = sshkey_puts(key, m)) != 0 ||
504	    (r = sshbuf_put_u32(m, pubkey_auth_attempt)) != 0)
505		fatal_fr(r, "assemble");
506
507	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYALLOWED, m);
508
509	debug3_f("waiting for MONITOR_ANS_KEYALLOWED");
510	mm_request_receive_expect(pmonitor->m_recvfd,
511	    MONITOR_ANS_KEYALLOWED, m);
512
513	if ((r = sshbuf_get_u32(m, &allowed)) != 0)
514		fatal_fr(r, "parse");
515	if (allowed && type == MM_USERKEY &&
516	    (r = sshauthopt_deserialise(m, &opts)) != 0)
517		fatal_fr(r, "sshauthopt_deserialise");
518	sshbuf_free(m);
519
520	if (authoptp != NULL) {
521		*authoptp = opts;
522		opts = NULL;
523	}
524	sshauthopt_free(opts);
525
526	return allowed;
527}
528
529/*
530 * This key verify needs to send the key type along, because the
531 * privileged parent makes the decision if the key is allowed
532 * for authentication.
533 */
534
535int
536mm_sshkey_verify(const struct sshkey *key, const u_char *sig, size_t siglen,
537    const u_char *data, size_t datalen, const char *sigalg, u_int compat,
538    struct sshkey_sig_details **sig_detailsp)
539{
540	struct sshbuf *m;
541	u_int encoded_ret = 0;
542	int r;
543	u_char sig_details_present, flags;
544	u_int counter;
545
546	debug3_f("entering");
547
548	if (sig_detailsp != NULL)
549		*sig_detailsp = NULL;
550	if ((m = sshbuf_new()) == NULL)
551		fatal_f("sshbuf_new failed");
552	if ((r = sshkey_puts(key, m)) != 0 ||
553	    (r = sshbuf_put_string(m, sig, siglen)) != 0 ||
554	    (r = sshbuf_put_string(m, data, datalen)) != 0 ||
555	    (r = sshbuf_put_cstring(m, sigalg == NULL ? "" : sigalg)) != 0)
556		fatal_fr(r, "assemble");
557
558	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYVERIFY, m);
559
560	debug3_f("waiting for MONITOR_ANS_KEYVERIFY");
561	mm_request_receive_expect(pmonitor->m_recvfd,
562	    MONITOR_ANS_KEYVERIFY, m);
563
564	if ((r = sshbuf_get_u32(m, &encoded_ret)) != 0 ||
565	    (r = sshbuf_get_u8(m, &sig_details_present)) != 0)
566		fatal_fr(r, "parse");
567	if (sig_details_present && encoded_ret == 0) {
568		if ((r = sshbuf_get_u32(m, &counter)) != 0 ||
569		    (r = sshbuf_get_u8(m, &flags)) != 0)
570			fatal_fr(r, "parse sig_details");
571		if (sig_detailsp != NULL) {
572			*sig_detailsp = xcalloc(1, sizeof(**sig_detailsp));
573			(*sig_detailsp)->sk_counter = counter;
574			(*sig_detailsp)->sk_flags = flags;
575		}
576	}
577
578	sshbuf_free(m);
579
580	if (encoded_ret != 0)
581		return SSH_ERR_SIGNATURE_INVALID;
582	return 0;
583}
584
585void
586mm_send_keystate(struct ssh *ssh, struct monitor *monitor)
587{
588	struct sshbuf *m;
589	int r;
590
591	if ((m = sshbuf_new()) == NULL)
592		fatal_f("sshbuf_new failed");
593	if ((r = ssh_packet_get_state(ssh, m)) != 0)
594		fatal_fr(r, "ssh_packet_get_state");
595	mm_request_send(monitor->m_recvfd, MONITOR_REQ_KEYEXPORT, m);
596	debug3_f("Finished sending state");
597	sshbuf_free(m);
598}
599
600int
601mm_pty_allocate(int *ptyfd, int *ttyfd, char *namebuf, size_t namebuflen)
602{
603	struct sshbuf *m;
604	char *p, *msg;
605	int success = 0, tmp1 = -1, tmp2 = -1, r;
606
607	/* Kludge: ensure there are fds free to receive the pty/tty */
608	if ((tmp1 = dup(pmonitor->m_recvfd)) == -1 ||
609	    (tmp2 = dup(pmonitor->m_recvfd)) == -1) {
610		error_f("cannot allocate fds for pty");
611		if (tmp1 >= 0)
612			close(tmp1);
613		return 0;
614	}
615	close(tmp1);
616	close(tmp2);
617
618	if ((m = sshbuf_new()) == NULL)
619		fatal_f("sshbuf_new failed");
620	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTY, m);
621
622	debug3_f("waiting for MONITOR_ANS_PTY");
623	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PTY, m);
624
625	if ((r = sshbuf_get_u32(m, &success)) != 0)
626		fatal_fr(r, "parse success");
627	if (success == 0) {
628		debug3_f("pty alloc failed");
629		sshbuf_free(m);
630		return (0);
631	}
632	if ((r = sshbuf_get_cstring(m, &p, NULL)) != 0 ||
633	    (r = sshbuf_get_cstring(m, &msg, NULL)) != 0)
634		fatal_fr(r, "parse");
635	sshbuf_free(m);
636
637	strlcpy(namebuf, p, namebuflen); /* Possible truncation */
638	free(p);
639
640	if ((r = sshbuf_put(loginmsg, msg, strlen(msg))) != 0)
641		fatal_fr(r, "put loginmsg");
642	free(msg);
643
644	if ((*ptyfd = mm_receive_fd(pmonitor->m_recvfd)) == -1 ||
645	    (*ttyfd = mm_receive_fd(pmonitor->m_recvfd)) == -1)
646		fatal_f("receive fds failed");
647
648	/* Success */
649	return (1);
650}
651
652void
653mm_session_pty_cleanup2(Session *s)
654{
655	struct sshbuf *m;
656	int r;
657
658	if (s->ttyfd == -1)
659		return;
660	if ((m = sshbuf_new()) == NULL)
661		fatal_f("sshbuf_new failed");
662	if ((r = sshbuf_put_cstring(m, s->tty)) != 0)
663		fatal_fr(r, "assmble");
664	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTYCLEANUP, m);
665	sshbuf_free(m);
666
667	/* closed dup'ed master */
668	if (s->ptymaster != -1 && close(s->ptymaster) == -1)
669		error("close(s->ptymaster/%d): %s",
670		    s->ptymaster, strerror(errno));
671
672	/* unlink pty from session */
673	s->ttyfd = -1;
674}
675
676/* Request process termination */
677
678void
679mm_terminate(void)
680{
681	struct sshbuf *m;
682
683	if ((m = sshbuf_new()) == NULL)
684		fatal_f("sshbuf_new failed");
685	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_TERM, m);
686	sshbuf_free(m);
687}
688
689static void
690mm_chall_setup(char **name, char **infotxt, u_int *numprompts,
691    char ***prompts, u_int **echo_on)
692{
693	*name = xstrdup("");
694	*infotxt = xstrdup("");
695	*numprompts = 1;
696	*prompts = xcalloc(*numprompts, sizeof(char *));
697	*echo_on = xcalloc(*numprompts, sizeof(u_int));
698	(*echo_on)[0] = 0;
699}
700
701int
702mm_bsdauth_query(void *ctx, char **name, char **infotxt,
703   u_int *numprompts, char ***prompts, u_int **echo_on)
704{
705	struct sshbuf *m;
706	u_int success;
707	char *challenge;
708	int r;
709
710	debug3_f("entering");
711
712	if ((m = sshbuf_new()) == NULL)
713		fatal_f("sshbuf_new failed");
714	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHQUERY, m);
715
716	mm_request_receive_expect(pmonitor->m_recvfd,
717	    MONITOR_ANS_BSDAUTHQUERY, m);
718	if ((r = sshbuf_get_u32(m, &success)) != 0)
719		fatal_fr(r, "parse success");
720	if (success == 0) {
721		debug3_f("no challenge");
722		sshbuf_free(m);
723		return (-1);
724	}
725
726	/* Get the challenge, and format the response */
727	if ((r = sshbuf_get_cstring(m, &challenge, NULL)) != 0)
728		fatal_fr(r, "parse challenge");
729	sshbuf_free(m);
730
731	mm_chall_setup(name, infotxt, numprompts, prompts, echo_on);
732	(*prompts)[0] = challenge;
733
734	debug3_f("received challenge: %s", challenge);
735
736	return (0);
737}
738
739int
740mm_bsdauth_respond(void *ctx, u_int numresponses, char **responses)
741{
742	struct sshbuf *m;
743	int r, authok;
744
745	debug3_f("entering");
746	if (numresponses != 1)
747		return (-1);
748
749	if ((m = sshbuf_new()) == NULL)
750		fatal_f("sshbuf_new failed");
751	if ((r = sshbuf_put_cstring(m, responses[0])) != 0)
752		fatal_fr(r, "assemble");
753	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHRESPOND, m);
754
755	mm_request_receive_expect(pmonitor->m_recvfd,
756	    MONITOR_ANS_BSDAUTHRESPOND, m);
757
758	if ((r = sshbuf_get_u32(m, &authok)) != 0)
759		fatal_fr(r, "parse");
760	sshbuf_free(m);
761
762	return ((authok == 0) ? -1 : 0);
763}
764
765#ifdef GSSAPI
766OM_uint32
767mm_ssh_gssapi_server_ctx(Gssctxt **ctx, gss_OID goid)
768{
769	struct sshbuf *m;
770	OM_uint32 major;
771	int r;
772
773	/* Client doesn't get to see the context */
774	*ctx = NULL;
775
776	if ((m = sshbuf_new()) == NULL)
777		fatal_f("sshbuf_new failed");
778	if ((r = sshbuf_put_string(m, goid->elements, goid->length)) != 0)
779		fatal_fr(r, "assemble");
780
781	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSETUP, m);
782	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSETUP, m);
783
784	if ((r = sshbuf_get_u32(m, &major)) != 0)
785		fatal_fr(r, "parse");
786
787	sshbuf_free(m);
788	return (major);
789}
790
791OM_uint32
792mm_ssh_gssapi_accept_ctx(Gssctxt *ctx, gss_buffer_desc *in,
793    gss_buffer_desc *out, OM_uint32 *flagsp)
794{
795	struct sshbuf *m;
796	OM_uint32 major;
797	u_int flags;
798	int r;
799
800	if ((m = sshbuf_new()) == NULL)
801		fatal_f("sshbuf_new failed");
802	if ((r = sshbuf_put_string(m, in->value, in->length)) != 0)
803		fatal_fr(r, "assemble");
804
805	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSTEP, m);
806	mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSTEP, m);
807
808	if ((r = sshbuf_get_u32(m, &major)) != 0 ||
809	    (r = ssh_gssapi_get_buffer_desc(m, out)) != 0)
810		fatal_fr(r, "parse");
811	if (flagsp != NULL) {
812		if ((r = sshbuf_get_u32(m, &flags)) != 0)
813			fatal_fr(r, "parse flags");
814		*flagsp = flags;
815	}
816
817	sshbuf_free(m);
818
819	return (major);
820}
821
822OM_uint32
823mm_ssh_gssapi_checkmic(Gssctxt *ctx, gss_buffer_t gssbuf, gss_buffer_t gssmic)
824{
825	struct sshbuf *m;
826	OM_uint32 major;
827	int r;
828
829	if ((m = sshbuf_new()) == NULL)
830		fatal_f("sshbuf_new failed");
831	if ((r = sshbuf_put_string(m, gssbuf->value, gssbuf->length)) != 0 ||
832	    (r = sshbuf_put_string(m, gssmic->value, gssmic->length)) != 0)
833		fatal_fr(r, "assemble");
834
835	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSCHECKMIC, m);
836	mm_request_receive_expect(pmonitor->m_recvfd,
837	    MONITOR_ANS_GSSCHECKMIC, m);
838
839	if ((r = sshbuf_get_u32(m, &major)) != 0)
840		fatal_fr(r, "parse");
841	sshbuf_free(m);
842	return(major);
843}
844
845int
846mm_ssh_gssapi_userok(char *user)
847{
848	struct sshbuf *m;
849	int r, authenticated = 0;
850
851	if ((m = sshbuf_new()) == NULL)
852		fatal_f("sshbuf_new failed");
853
854	mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSUSEROK, m);
855	mm_request_receive_expect(pmonitor->m_recvfd,
856	    MONITOR_ANS_GSSUSEROK, m);
857
858	if ((r = sshbuf_get_u32(m, &authenticated)) != 0)
859		fatal_fr(r, "parse");
860
861	sshbuf_free(m);
862	debug3_f("user %sauthenticated", authenticated ? "" : "not ");
863	return (authenticated);
864}
865#endif /* GSSAPI */
866
867/*
868 * Inform channels layer of permitopen options for a single forwarding
869 * direction (local/remote).
870 */
871static void
872server_process_permitopen_list(struct ssh *ssh, int listen,
873    char **opens, u_int num_opens)
874{
875	u_int i;
876	int port;
877	char *host, *arg, *oarg;
878	int where = listen ? FORWARD_REMOTE : FORWARD_LOCAL;
879	const char *what = listen ? "permitlisten" : "permitopen";
880
881	channel_clear_permission(ssh, FORWARD_ADM, where);
882	if (num_opens == 0)
883		return; /* permit any */
884
885	/* handle keywords: "any" / "none" */
886	if (num_opens == 1 && strcmp(opens[0], "any") == 0)
887		return;
888	if (num_opens == 1 && strcmp(opens[0], "none") == 0) {
889		channel_disable_admin(ssh, where);
890		return;
891	}
892	/* Otherwise treat it as a list of permitted host:port */
893	for (i = 0; i < num_opens; i++) {
894		oarg = arg = xstrdup(opens[i]);
895		host = hpdelim(&arg);
896		if (host == NULL)
897			fatal_f("missing host in %s", what);
898		host = cleanhostname(host);
899		if (arg == NULL || ((port = permitopen_port(arg)) < 0))
900			fatal_f("bad port number in %s", what);
901		/* Send it to channels layer */
902		channel_add_permission(ssh, FORWARD_ADM,
903		    where, host, port);
904		free(oarg);
905	}
906}
907
908/*
909 * Inform channels layer of permitopen options from configuration.
910 */
911void
912server_process_permitopen(struct ssh *ssh)
913{
914	server_process_permitopen_list(ssh, 0,
915	    options.permitted_opens, options.num_permitted_opens);
916	server_process_permitopen_list(ssh, 1,
917	    options.permitted_listens, options.num_permitted_listens);
918}
919
920void
921server_process_channel_timeouts(struct ssh *ssh)
922{
923	u_int i, secs;
924	char *type;
925
926	debug3_f("setting %u timeouts", options.num_channel_timeouts);
927	channel_clear_timeouts(ssh);
928	for (i = 0; i < options.num_channel_timeouts; i++) {
929		if (parse_pattern_interval(options.channel_timeouts[i],
930		    &type, &secs) != 0) {
931			fatal_f("internal error: bad timeout %s",
932			    options.channel_timeouts[i]);
933		}
934		channel_add_timeout(ssh, type, secs);
935		free(type);
936	}
937}
938
939struct connection_info *
940server_get_connection_info(struct ssh *ssh, int populate, int use_dns)
941{
942	static struct connection_info ci;
943
944	if (ssh == NULL || !populate)
945		return &ci;
946	ci.host = use_dns ? ssh_remote_hostname(ssh) : ssh_remote_ipaddr(ssh);
947	ci.address = ssh_remote_ipaddr(ssh);
948	ci.laddress = ssh_local_ipaddr(ssh);
949	ci.lport = ssh_local_port(ssh);
950	ci.rdomain = ssh_packet_rdomain_in(ssh);
951	return &ci;
952}
953
954