1 /* $OpenBSD: monitor_wrap.c,v 1.79 2014/02/02 03:44:31 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 "includes.h"
29
30 #include <sys/types.h>
31 #include <sys/uio.h>
32
33 #include <errno.h>
34 #include <pwd.h>
35 #include <signal.h>
36 #include <stdarg.h>
37 #include <stdio.h>
38 #include <string.h>
39 #include <unistd.h>
40
41 #include <openssl/bn.h>
42 #include <openssl/dh.h>
43 #include <openssl/evp.h>
44
45 #include "openbsd-compat/sys-queue.h"
46 #include "xmalloc.h"
47 #include "ssh.h"
48 #include "dh.h"
49 #include "buffer.h"
50 #include "key.h"
51 #include "cipher.h"
52 #include "kex.h"
53 #include "hostfile.h"
54 #include "auth.h"
55 #include "auth-options.h"
56 #include "packet.h"
57 #include "mac.h"
58 #include "log.h"
59 #ifdef TARGET_OS_MAC /* XXX Broken krb5 headers on Mac */
60 #undef TARGET_OS_MAC
61 #include "zlib.h"
62 #define TARGET_OS_MAC 1
63 #else
64 #include "zlib.h"
65 #endif
66 #include "monitor.h"
67 #ifdef GSSAPI
68 #include "ssh-gss.h"
69 #endif
70 #include "monitor_wrap.h"
71 #include "atomicio.h"
72 #include "monitor_fdpass.h"
73 #include "misc.h"
74 #include "uuencode.h"
75
76 #include "channels.h"
77 #include "session.h"
78 #include "servconf.h"
79 #include "roaming.h"
80
81 /* Imports */
82 extern int compat20;
83 extern z_stream incoming_stream;
84 extern z_stream outgoing_stream;
85 extern struct monitor *pmonitor;
86 extern Buffer loginmsg;
87 extern ServerOptions options;
88
89 void
mm_log_handler(LogLevel level,const char * msg,void * ctx)90 mm_log_handler(LogLevel level, const char *msg, void *ctx)
91 {
92 Buffer log_msg;
93 struct monitor *mon = (struct monitor *)ctx;
94
95 if (mon->m_log_sendfd == -1)
96 fatal("%s: no log channel", __func__);
97
98 buffer_init(&log_msg);
99 /*
100 * Placeholder for packet length. Will be filled in with the actual
101 * packet length once the packet has been constucted. This saves
102 * fragile math.
103 */
104 buffer_put_int(&log_msg, 0);
105
106 buffer_put_int(&log_msg, level);
107 buffer_put_cstring(&log_msg, msg);
108 put_u32(buffer_ptr(&log_msg), buffer_len(&log_msg) - 4);
109 if (atomicio(vwrite, mon->m_log_sendfd, buffer_ptr(&log_msg),
110 buffer_len(&log_msg)) != buffer_len(&log_msg))
111 fatal("%s: write: %s", __func__, strerror(errno));
112 buffer_free(&log_msg);
113 }
114
115 int
mm_is_monitor(void)116 mm_is_monitor(void)
117 {
118 /*
119 * m_pid is only set in the privileged part, and
120 * points to the unprivileged child.
121 */
122 return (pmonitor && pmonitor->m_pid > 0);
123 }
124
125 void
mm_request_send(int sock,enum monitor_reqtype type,Buffer * m)126 mm_request_send(int sock, enum monitor_reqtype type, Buffer *m)
127 {
128 u_int mlen = buffer_len(m);
129 u_char buf[5];
130
131 debug3("%s entering: type %d", __func__, type);
132
133 put_u32(buf, mlen + 1);
134 buf[4] = (u_char) type; /* 1st byte of payload is mesg-type */
135 if (atomicio(vwrite, sock, buf, sizeof(buf)) != sizeof(buf))
136 fatal("%s: write: %s", __func__, strerror(errno));
137 if (atomicio(vwrite, sock, buffer_ptr(m), mlen) != mlen)
138 fatal("%s: write: %s", __func__, strerror(errno));
139 }
140
141 void
mm_request_receive(int sock,Buffer * m)142 mm_request_receive(int sock, Buffer *m)
143 {
144 u_char buf[4];
145 u_int msg_len;
146
147 debug3("%s entering", __func__);
148
149 if (atomicio(read, sock, buf, sizeof(buf)) != sizeof(buf)) {
150 if (errno == EPIPE)
151 cleanup_exit(255);
152 fatal("%s: read: %s", __func__, strerror(errno));
153 }
154 msg_len = get_u32(buf);
155 if (msg_len > 256 * 1024)
156 fatal("%s: read: bad msg_len %d", __func__, msg_len);
157 buffer_clear(m);
158 buffer_append_space(m, msg_len);
159 if (atomicio(read, sock, buffer_ptr(m), msg_len) != msg_len)
160 fatal("%s: read: %s", __func__, strerror(errno));
161 }
162
163 void
mm_request_receive_expect(int sock,enum monitor_reqtype type,Buffer * m)164 mm_request_receive_expect(int sock, enum monitor_reqtype type, Buffer *m)
165 {
166 u_char rtype;
167
168 debug3("%s entering: type %d", __func__, type);
169
170 mm_request_receive(sock, m);
171 rtype = buffer_get_char(m);
172 if (rtype != type)
173 fatal("%s: read: rtype %d != type %d", __func__,
174 rtype, type);
175 }
176
177 DH *
mm_choose_dh(int min,int nbits,int max)178 mm_choose_dh(int min, int nbits, int max)
179 {
180 BIGNUM *p, *g;
181 int success = 0;
182 Buffer m;
183
184 buffer_init(&m);
185 buffer_put_int(&m, min);
186 buffer_put_int(&m, nbits);
187 buffer_put_int(&m, max);
188
189 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_MODULI, &m);
190
191 debug3("%s: waiting for MONITOR_ANS_MODULI", __func__);
192 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_MODULI, &m);
193
194 success = buffer_get_char(&m);
195 if (success == 0)
196 fatal("%s: MONITOR_ANS_MODULI failed", __func__);
197
198 if ((p = BN_new()) == NULL)
199 fatal("%s: BN_new failed", __func__);
200 if ((g = BN_new()) == NULL)
201 fatal("%s: BN_new failed", __func__);
202 buffer_get_bignum2(&m, p);
203 buffer_get_bignum2(&m, g);
204
205 debug3("%s: remaining %d", __func__, buffer_len(&m));
206 buffer_free(&m);
207
208 return (dh_new_group(g, p));
209 }
210
211 int
mm_key_sign(Key * key,u_char ** sigp,u_int * lenp,u_char * data,u_int datalen)212 mm_key_sign(Key *key, u_char **sigp, u_int *lenp, u_char *data, u_int datalen)
213 {
214 Kex *kex = *pmonitor->m_pkex;
215 Buffer m;
216
217 debug3("%s entering", __func__);
218
219 buffer_init(&m);
220 buffer_put_int(&m, kex->host_key_index(key));
221 buffer_put_string(&m, data, datalen);
222
223 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SIGN, &m);
224
225 debug3("%s: waiting for MONITOR_ANS_SIGN", __func__);
226 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SIGN, &m);
227 *sigp = buffer_get_string(&m, lenp);
228 buffer_free(&m);
229
230 return (0);
231 }
232
233 struct passwd *
mm_getpwnamallow(const char * username)234 mm_getpwnamallow(const char *username)
235 {
236 Buffer m;
237 struct passwd *pw;
238 u_int len, i;
239 ServerOptions *newopts;
240
241 debug3("%s entering", __func__);
242
243 buffer_init(&m);
244 buffer_put_cstring(&m, username);
245
246 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PWNAM, &m);
247
248 debug3("%s: waiting for MONITOR_ANS_PWNAM", __func__);
249 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PWNAM, &m);
250
251 if (buffer_get_char(&m) == 0) {
252 pw = NULL;
253 goto out;
254 }
255 pw = buffer_get_string(&m, &len);
256 if (len != sizeof(struct passwd))
257 fatal("%s: struct passwd size mismatch", __func__);
258 pw->pw_name = buffer_get_string(&m, NULL);
259 pw->pw_passwd = buffer_get_string(&m, NULL);
260 #ifdef HAVE_STRUCT_PASSWD_PW_GECOS
261 pw->pw_gecos = buffer_get_string(&m, NULL);
262 #endif
263 #ifdef HAVE_STRUCT_PASSWD_PW_CLASS
264 pw->pw_class = buffer_get_string(&m, NULL);
265 #endif
266 pw->pw_dir = buffer_get_string(&m, NULL);
267 pw->pw_shell = buffer_get_string(&m, NULL);
268
269 out:
270 /* copy options block as a Match directive may have changed some */
271 newopts = buffer_get_string(&m, &len);
272 if (len != sizeof(*newopts))
273 fatal("%s: option block size mismatch", __func__);
274
275 #define M_CP_STROPT(x) do { \
276 if (newopts->x != NULL) \
277 newopts->x = buffer_get_string(&m, NULL); \
278 } while (0)
279 #define M_CP_STRARRAYOPT(x, nx) do { \
280 for (i = 0; i < newopts->nx; i++) \
281 newopts->x[i] = buffer_get_string(&m, NULL); \
282 } while (0)
283 /* See comment in servconf.h */
284 COPY_MATCH_STRING_OPTS();
285 #undef M_CP_STROPT
286 #undef M_CP_STRARRAYOPT
287
288 copy_set_server_options(&options, newopts, 1);
289 free(newopts);
290
291 buffer_free(&m);
292
293 return (pw);
294 }
295
296 char *
mm_auth2_read_banner(void)297 mm_auth2_read_banner(void)
298 {
299 Buffer m;
300 char *banner;
301
302 debug3("%s entering", __func__);
303
304 buffer_init(&m);
305 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTH2_READ_BANNER, &m);
306 buffer_clear(&m);
307
308 mm_request_receive_expect(pmonitor->m_recvfd,
309 MONITOR_ANS_AUTH2_READ_BANNER, &m);
310 banner = buffer_get_string(&m, NULL);
311 buffer_free(&m);
312
313 /* treat empty banner as missing banner */
314 if (strlen(banner) == 0) {
315 free(banner);
316 banner = NULL;
317 }
318 return (banner);
319 }
320
321 /* Inform the privileged process about service and style */
322
323 void
mm_inform_authserv(char * service,char * style)324 mm_inform_authserv(char *service, char *style)
325 {
326 Buffer m;
327
328 debug3("%s entering", __func__);
329
330 buffer_init(&m);
331 buffer_put_cstring(&m, service);
332 buffer_put_cstring(&m, style ? style : "");
333
334 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHSERV, &m);
335
336 buffer_free(&m);
337 }
338
339 /* Do the password authentication */
340 int
mm_auth_password(Authctxt * authctxt,char * password)341 mm_auth_password(Authctxt *authctxt, char *password)
342 {
343 Buffer m;
344 int authenticated = 0;
345
346 debug3("%s entering", __func__);
347
348 buffer_init(&m);
349 buffer_put_cstring(&m, password);
350 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHPASSWORD, &m);
351
352 debug3("%s: waiting for MONITOR_ANS_AUTHPASSWORD", __func__);
353 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_AUTHPASSWORD, &m);
354
355 authenticated = buffer_get_int(&m);
356
357 buffer_free(&m);
358
359 debug3("%s: user %sauthenticated",
360 __func__, authenticated ? "" : "not ");
361 return (authenticated);
362 }
363
364 int
mm_user_key_allowed(struct passwd * pw,Key * key)365 mm_user_key_allowed(struct passwd *pw, Key *key)
366 {
367 return (mm_key_allowed(MM_USERKEY, NULL, NULL, key));
368 }
369
370 int
mm_hostbased_key_allowed(struct passwd * pw,char * user,char * host,Key * key)371 mm_hostbased_key_allowed(struct passwd *pw, char *user, char *host,
372 Key *key)
373 {
374 return (mm_key_allowed(MM_HOSTKEY, user, host, key));
375 }
376
377 int
mm_auth_rhosts_rsa_key_allowed(struct passwd * pw,char * user,char * host,Key * key)378 mm_auth_rhosts_rsa_key_allowed(struct passwd *pw, char *user,
379 char *host, Key *key)
380 {
381 int ret;
382
383 key->type = KEY_RSA; /* XXX hack for key_to_blob */
384 ret = mm_key_allowed(MM_RSAHOSTKEY, user, host, key);
385 key->type = KEY_RSA1;
386 return (ret);
387 }
388
389 int
mm_key_allowed(enum mm_keytype type,char * user,char * host,Key * key)390 mm_key_allowed(enum mm_keytype type, char *user, char *host, Key *key)
391 {
392 Buffer m;
393 u_char *blob;
394 u_int len;
395 int allowed = 0, have_forced = 0;
396
397 debug3("%s entering", __func__);
398
399 /* Convert the key to a blob and the pass it over */
400 if (!key_to_blob(key, &blob, &len))
401 return (0);
402
403 buffer_init(&m);
404 buffer_put_int(&m, type);
405 buffer_put_cstring(&m, user ? user : "");
406 buffer_put_cstring(&m, host ? host : "");
407 buffer_put_string(&m, blob, len);
408 free(blob);
409
410 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYALLOWED, &m);
411
412 debug3("%s: waiting for MONITOR_ANS_KEYALLOWED", __func__);
413 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_KEYALLOWED, &m);
414
415 allowed = buffer_get_int(&m);
416
417 /* fake forced command */
418 auth_clear_options();
419 have_forced = buffer_get_int(&m);
420 forced_command = have_forced ? xstrdup("true") : NULL;
421
422 buffer_free(&m);
423
424 return (allowed);
425 }
426
427 /*
428 * This key verify needs to send the key type along, because the
429 * privileged parent makes the decision if the key is allowed
430 * for authentication.
431 */
432
433 int
mm_key_verify(Key * key,u_char * sig,u_int siglen,u_char * data,u_int datalen)434 mm_key_verify(Key *key, u_char *sig, u_int siglen, u_char *data, u_int datalen)
435 {
436 Buffer m;
437 u_char *blob;
438 u_int len;
439 int verified = 0;
440
441 debug3("%s entering", __func__);
442
443 /* Convert the key to a blob and the pass it over */
444 if (!key_to_blob(key, &blob, &len))
445 return (0);
446
447 buffer_init(&m);
448 buffer_put_string(&m, blob, len);
449 buffer_put_string(&m, sig, siglen);
450 buffer_put_string(&m, data, datalen);
451 free(blob);
452
453 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYVERIFY, &m);
454
455 debug3("%s: waiting for MONITOR_ANS_KEYVERIFY", __func__);
456 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_KEYVERIFY, &m);
457
458 verified = buffer_get_int(&m);
459
460 buffer_free(&m);
461
462 return (verified);
463 }
464
465 /* Export key state after authentication */
466 Newkeys *
mm_newkeys_from_blob(u_char * blob,int blen)467 mm_newkeys_from_blob(u_char *blob, int blen)
468 {
469 Buffer b;
470 u_int len;
471 Newkeys *newkey = NULL;
472 Enc *enc;
473 Mac *mac;
474 Comp *comp;
475
476 debug3("%s: %p(%d)", __func__, blob, blen);
477 #ifdef DEBUG_PK
478 dump_base64(stderr, blob, blen);
479 #endif
480 buffer_init(&b);
481 buffer_append(&b, blob, blen);
482
483 newkey = xcalloc(1, sizeof(*newkey));
484 enc = &newkey->enc;
485 mac = &newkey->mac;
486 comp = &newkey->comp;
487
488 /* Enc structure */
489 enc->name = buffer_get_string(&b, NULL);
490 buffer_get(&b, &enc->cipher, sizeof(enc->cipher));
491 enc->enabled = buffer_get_int(&b);
492 enc->block_size = buffer_get_int(&b);
493 enc->key = buffer_get_string(&b, &enc->key_len);
494 enc->iv = buffer_get_string(&b, &enc->iv_len);
495
496 if (enc->name == NULL || cipher_by_name(enc->name) != enc->cipher)
497 fatal("%s: bad cipher name %s or pointer %p", __func__,
498 enc->name, enc->cipher);
499
500 /* Mac structure */
501 if (cipher_authlen(enc->cipher) == 0) {
502 mac->name = buffer_get_string(&b, NULL);
503 if (mac->name == NULL || mac_setup(mac, mac->name) == -1)
504 fatal("%s: can not setup mac %s", __func__, mac->name);
505 mac->enabled = buffer_get_int(&b);
506 mac->key = buffer_get_string(&b, &len);
507 if (len > mac->key_len)
508 fatal("%s: bad mac key length: %u > %d", __func__, len,
509 mac->key_len);
510 mac->key_len = len;
511 }
512
513 /* Comp structure */
514 comp->type = buffer_get_int(&b);
515 comp->enabled = buffer_get_int(&b);
516 comp->name = buffer_get_string(&b, NULL);
517
518 len = buffer_len(&b);
519 if (len != 0)
520 error("newkeys_from_blob: remaining bytes in blob %u", len);
521 buffer_free(&b);
522 return (newkey);
523 }
524
525 int
mm_newkeys_to_blob(int mode,u_char ** blobp,u_int * lenp)526 mm_newkeys_to_blob(int mode, u_char **blobp, u_int *lenp)
527 {
528 Buffer b;
529 int len;
530 Enc *enc;
531 Mac *mac;
532 Comp *comp;
533 Newkeys *newkey = (Newkeys *)packet_get_newkeys(mode);
534
535 debug3("%s: converting %p", __func__, newkey);
536
537 if (newkey == NULL) {
538 error("%s: newkey == NULL", __func__);
539 return 0;
540 }
541 enc = &newkey->enc;
542 mac = &newkey->mac;
543 comp = &newkey->comp;
544
545 buffer_init(&b);
546 /* Enc structure */
547 buffer_put_cstring(&b, enc->name);
548 /* The cipher struct is constant and shared, you export pointer */
549 buffer_append(&b, &enc->cipher, sizeof(enc->cipher));
550 buffer_put_int(&b, enc->enabled);
551 buffer_put_int(&b, enc->block_size);
552 buffer_put_string(&b, enc->key, enc->key_len);
553 packet_get_keyiv(mode, enc->iv, enc->iv_len);
554 buffer_put_string(&b, enc->iv, enc->iv_len);
555
556 /* Mac structure */
557 if (cipher_authlen(enc->cipher) == 0) {
558 buffer_put_cstring(&b, mac->name);
559 buffer_put_int(&b, mac->enabled);
560 buffer_put_string(&b, mac->key, mac->key_len);
561 }
562
563 /* Comp structure */
564 buffer_put_int(&b, comp->type);
565 buffer_put_int(&b, comp->enabled);
566 buffer_put_cstring(&b, comp->name);
567
568 len = buffer_len(&b);
569 if (lenp != NULL)
570 *lenp = len;
571 if (blobp != NULL) {
572 *blobp = xmalloc(len);
573 memcpy(*blobp, buffer_ptr(&b), len);
574 }
575 explicit_bzero(buffer_ptr(&b), len);
576 buffer_free(&b);
577 return len;
578 }
579
580 static void
mm_send_kex(Buffer * m,Kex * kex)581 mm_send_kex(Buffer *m, Kex *kex)
582 {
583 buffer_put_string(m, kex->session_id, kex->session_id_len);
584 buffer_put_int(m, kex->we_need);
585 buffer_put_int(m, kex->hostkey_type);
586 buffer_put_int(m, kex->kex_type);
587 buffer_put_string(m, buffer_ptr(&kex->my), buffer_len(&kex->my));
588 buffer_put_string(m, buffer_ptr(&kex->peer), buffer_len(&kex->peer));
589 buffer_put_int(m, kex->flags);
590 buffer_put_cstring(m, kex->client_version_string);
591 buffer_put_cstring(m, kex->server_version_string);
592 }
593
594 void
mm_send_keystate(struct monitor * monitor)595 mm_send_keystate(struct monitor *monitor)
596 {
597 Buffer m, *input, *output;
598 u_char *blob, *p;
599 u_int bloblen, plen;
600 u_int32_t seqnr, packets;
601 u_int64_t blocks, bytes;
602
603 buffer_init(&m);
604
605 if (!compat20) {
606 u_char iv[24];
607 u_char *key;
608 u_int ivlen, keylen;
609
610 buffer_put_int(&m, packet_get_protocol_flags());
611
612 buffer_put_int(&m, packet_get_ssh1_cipher());
613
614 debug3("%s: Sending ssh1 KEY+IV", __func__);
615 keylen = packet_get_encryption_key(NULL);
616 key = xmalloc(keylen+1); /* add 1 if keylen == 0 */
617 keylen = packet_get_encryption_key(key);
618 buffer_put_string(&m, key, keylen);
619 explicit_bzero(key, keylen);
620 free(key);
621
622 ivlen = packet_get_keyiv_len(MODE_OUT);
623 packet_get_keyiv(MODE_OUT, iv, ivlen);
624 buffer_put_string(&m, iv, ivlen);
625 ivlen = packet_get_keyiv_len(MODE_IN);
626 packet_get_keyiv(MODE_IN, iv, ivlen);
627 buffer_put_string(&m, iv, ivlen);
628 goto skip;
629 } else {
630 /* Kex for rekeying */
631 mm_send_kex(&m, *monitor->m_pkex);
632 }
633
634 debug3("%s: Sending new keys: %p %p",
635 __func__, packet_get_newkeys(MODE_OUT),
636 packet_get_newkeys(MODE_IN));
637
638 /* Keys from Kex */
639 if (!mm_newkeys_to_blob(MODE_OUT, &blob, &bloblen))
640 fatal("%s: conversion of newkeys failed", __func__);
641
642 buffer_put_string(&m, blob, bloblen);
643 free(blob);
644
645 if (!mm_newkeys_to_blob(MODE_IN, &blob, &bloblen))
646 fatal("%s: conversion of newkeys failed", __func__);
647
648 buffer_put_string(&m, blob, bloblen);
649 free(blob);
650
651 packet_get_state(MODE_OUT, &seqnr, &blocks, &packets, &bytes);
652 buffer_put_int(&m, seqnr);
653 buffer_put_int64(&m, blocks);
654 buffer_put_int(&m, packets);
655 buffer_put_int64(&m, bytes);
656 packet_get_state(MODE_IN, &seqnr, &blocks, &packets, &bytes);
657 buffer_put_int(&m, seqnr);
658 buffer_put_int64(&m, blocks);
659 buffer_put_int(&m, packets);
660 buffer_put_int64(&m, bytes);
661
662 debug3("%s: New keys have been sent", __func__);
663 skip:
664 /* More key context */
665 plen = packet_get_keycontext(MODE_OUT, NULL);
666 p = xmalloc(plen+1);
667 packet_get_keycontext(MODE_OUT, p);
668 buffer_put_string(&m, p, plen);
669 free(p);
670
671 plen = packet_get_keycontext(MODE_IN, NULL);
672 p = xmalloc(plen+1);
673 packet_get_keycontext(MODE_IN, p);
674 buffer_put_string(&m, p, plen);
675 free(p);
676
677 /* Compression state */
678 debug3("%s: Sending compression state", __func__);
679 buffer_put_string(&m, &outgoing_stream, sizeof(outgoing_stream));
680 buffer_put_string(&m, &incoming_stream, sizeof(incoming_stream));
681
682 /* Network I/O buffers */
683 input = (Buffer *)packet_get_input();
684 output = (Buffer *)packet_get_output();
685 buffer_put_string(&m, buffer_ptr(input), buffer_len(input));
686 buffer_put_string(&m, buffer_ptr(output), buffer_len(output));
687
688 /* Roaming */
689 if (compat20) {
690 buffer_put_int64(&m, get_sent_bytes());
691 buffer_put_int64(&m, get_recv_bytes());
692 }
693
694 mm_request_send(monitor->m_recvfd, MONITOR_REQ_KEYEXPORT, &m);
695 debug3("%s: Finished sending state", __func__);
696
697 buffer_free(&m);
698 }
699
700 int
mm_pty_allocate(int * ptyfd,int * ttyfd,char * namebuf,size_t namebuflen)701 mm_pty_allocate(int *ptyfd, int *ttyfd, char *namebuf, size_t namebuflen)
702 {
703 Buffer m;
704 char *p, *msg;
705 int success = 0, tmp1 = -1, tmp2 = -1;
706
707 /* Kludge: ensure there are fds free to receive the pty/tty */
708 if ((tmp1 = dup(pmonitor->m_recvfd)) == -1 ||
709 (tmp2 = dup(pmonitor->m_recvfd)) == -1) {
710 error("%s: cannot allocate fds for pty", __func__);
711 if (tmp1 > 0)
712 close(tmp1);
713 if (tmp2 > 0)
714 close(tmp2);
715 return 0;
716 }
717 close(tmp1);
718 close(tmp2);
719
720 buffer_init(&m);
721 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTY, &m);
722
723 debug3("%s: waiting for MONITOR_ANS_PTY", __func__);
724 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PTY, &m);
725
726 success = buffer_get_int(&m);
727 if (success == 0) {
728 debug3("%s: pty alloc failed", __func__);
729 buffer_free(&m);
730 return (0);
731 }
732 p = buffer_get_string(&m, NULL);
733 msg = buffer_get_string(&m, NULL);
734 buffer_free(&m);
735
736 strlcpy(namebuf, p, namebuflen); /* Possible truncation */
737 free(p);
738
739 buffer_append(&loginmsg, msg, strlen(msg));
740 free(msg);
741
742 if ((*ptyfd = mm_receive_fd(pmonitor->m_recvfd)) == -1 ||
743 (*ttyfd = mm_receive_fd(pmonitor->m_recvfd)) == -1)
744 fatal("%s: receive fds failed", __func__);
745
746 /* Success */
747 return (1);
748 }
749
750 void
mm_session_pty_cleanup2(Session * s)751 mm_session_pty_cleanup2(Session *s)
752 {
753 Buffer m;
754
755 if (s->ttyfd == -1)
756 return;
757 buffer_init(&m);
758 buffer_put_cstring(&m, s->tty);
759 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTYCLEANUP, &m);
760 buffer_free(&m);
761
762 /* closed dup'ed master */
763 if (s->ptymaster != -1 && close(s->ptymaster) < 0)
764 error("close(s->ptymaster/%d): %s",
765 s->ptymaster, strerror(errno));
766
767 /* unlink pty from session */
768 s->ttyfd = -1;
769 }
770
771 #ifdef USE_PAM
772 void
mm_start_pam(Authctxt * authctxt)773 mm_start_pam(Authctxt *authctxt)
774 {
775 Buffer m;
776
777 debug3("%s entering", __func__);
778 if (!options.use_pam)
779 fatal("UsePAM=no, but ended up in %s anyway", __func__);
780
781 buffer_init(&m);
782 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_START, &m);
783
784 buffer_free(&m);
785 }
786
787 u_int
mm_do_pam_account(void)788 mm_do_pam_account(void)
789 {
790 Buffer m;
791 u_int ret;
792 char *msg;
793
794 debug3("%s entering", __func__);
795 if (!options.use_pam)
796 fatal("UsePAM=no, but ended up in %s anyway", __func__);
797
798 buffer_init(&m);
799 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_ACCOUNT, &m);
800
801 mm_request_receive_expect(pmonitor->m_recvfd,
802 MONITOR_ANS_PAM_ACCOUNT, &m);
803 ret = buffer_get_int(&m);
804 msg = buffer_get_string(&m, NULL);
805 buffer_append(&loginmsg, msg, strlen(msg));
806 free(msg);
807
808 buffer_free(&m);
809
810 debug3("%s returning %d", __func__, ret);
811
812 return (ret);
813 }
814
815 void *
mm_sshpam_init_ctx(Authctxt * authctxt)816 mm_sshpam_init_ctx(Authctxt *authctxt)
817 {
818 Buffer m;
819 int success;
820
821 debug3("%s", __func__);
822 buffer_init(&m);
823 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_INIT_CTX, &m);
824 debug3("%s: waiting for MONITOR_ANS_PAM_INIT_CTX", __func__);
825 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_INIT_CTX, &m);
826 success = buffer_get_int(&m);
827 if (success == 0) {
828 debug3("%s: pam_init_ctx failed", __func__);
829 buffer_free(&m);
830 return (NULL);
831 }
832 buffer_free(&m);
833 return (authctxt);
834 }
835
836 int
mm_sshpam_query(void * ctx,char ** name,char ** info,u_int * num,char *** prompts,u_int ** echo_on)837 mm_sshpam_query(void *ctx, char **name, char **info,
838 u_int *num, char ***prompts, u_int **echo_on)
839 {
840 Buffer m;
841 u_int i;
842 int ret;
843
844 debug3("%s", __func__);
845 buffer_init(&m);
846 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_QUERY, &m);
847 debug3("%s: waiting for MONITOR_ANS_PAM_QUERY", __func__);
848 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_QUERY, &m);
849 ret = buffer_get_int(&m);
850 debug3("%s: pam_query returned %d", __func__, ret);
851 *name = buffer_get_string(&m, NULL);
852 *info = buffer_get_string(&m, NULL);
853 *num = buffer_get_int(&m);
854 if (*num > PAM_MAX_NUM_MSG)
855 fatal("%s: recieved %u PAM messages, expected <= %u",
856 __func__, *num, PAM_MAX_NUM_MSG);
857 *prompts = xcalloc((*num + 1), sizeof(char *));
858 *echo_on = xcalloc((*num + 1), sizeof(u_int));
859 for (i = 0; i < *num; ++i) {
860 (*prompts)[i] = buffer_get_string(&m, NULL);
861 (*echo_on)[i] = buffer_get_int(&m);
862 }
863 buffer_free(&m);
864 return (ret);
865 }
866
867 int
mm_sshpam_respond(void * ctx,u_int num,char ** resp)868 mm_sshpam_respond(void *ctx, u_int num, char **resp)
869 {
870 Buffer m;
871 u_int i;
872 int ret;
873
874 debug3("%s", __func__);
875 buffer_init(&m);
876 buffer_put_int(&m, num);
877 for (i = 0; i < num; ++i)
878 buffer_put_cstring(&m, resp[i]);
879 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_RESPOND, &m);
880 debug3("%s: waiting for MONITOR_ANS_PAM_RESPOND", __func__);
881 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_RESPOND, &m);
882 ret = buffer_get_int(&m);
883 debug3("%s: pam_respond returned %d", __func__, ret);
884 buffer_free(&m);
885 return (ret);
886 }
887
888 void
mm_sshpam_free_ctx(void * ctxtp)889 mm_sshpam_free_ctx(void *ctxtp)
890 {
891 Buffer m;
892
893 debug3("%s", __func__);
894 buffer_init(&m);
895 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PAM_FREE_CTX, &m);
896 debug3("%s: waiting for MONITOR_ANS_PAM_FREE_CTX", __func__);
897 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PAM_FREE_CTX, &m);
898 buffer_free(&m);
899 }
900 #endif /* USE_PAM */
901
902 /* Request process termination */
903
904 void
mm_terminate(void)905 mm_terminate(void)
906 {
907 Buffer m;
908
909 buffer_init(&m);
910 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_TERM, &m);
911 buffer_free(&m);
912 }
913
914 int
mm_ssh1_session_key(BIGNUM * num)915 mm_ssh1_session_key(BIGNUM *num)
916 {
917 int rsafail;
918 Buffer m;
919
920 buffer_init(&m);
921 buffer_put_bignum2(&m, num);
922 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SESSKEY, &m);
923
924 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SESSKEY, &m);
925
926 rsafail = buffer_get_int(&m);
927 buffer_get_bignum2(&m, num);
928
929 buffer_free(&m);
930
931 return (rsafail);
932 }
933
934 static void
mm_chall_setup(char ** name,char ** infotxt,u_int * numprompts,char *** prompts,u_int ** echo_on)935 mm_chall_setup(char **name, char **infotxt, u_int *numprompts,
936 char ***prompts, u_int **echo_on)
937 {
938 *name = xstrdup("");
939 *infotxt = xstrdup("");
940 *numprompts = 1;
941 *prompts = xcalloc(*numprompts, sizeof(char *));
942 *echo_on = xcalloc(*numprompts, sizeof(u_int));
943 (*echo_on)[0] = 0;
944 }
945
946 int
mm_bsdauth_query(void * ctx,char ** name,char ** infotxt,u_int * numprompts,char *** prompts,u_int ** echo_on)947 mm_bsdauth_query(void *ctx, char **name, char **infotxt,
948 u_int *numprompts, char ***prompts, u_int **echo_on)
949 {
950 Buffer m;
951 u_int success;
952 char *challenge;
953
954 debug3("%s: entering", __func__);
955
956 buffer_init(&m);
957 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHQUERY, &m);
958
959 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_BSDAUTHQUERY,
960 &m);
961 success = buffer_get_int(&m);
962 if (success == 0) {
963 debug3("%s: no challenge", __func__);
964 buffer_free(&m);
965 return (-1);
966 }
967
968 /* Get the challenge, and format the response */
969 challenge = buffer_get_string(&m, NULL);
970 buffer_free(&m);
971
972 mm_chall_setup(name, infotxt, numprompts, prompts, echo_on);
973 (*prompts)[0] = challenge;
974
975 debug3("%s: received challenge: %s", __func__, challenge);
976
977 return (0);
978 }
979
980 int
mm_bsdauth_respond(void * ctx,u_int numresponses,char ** responses)981 mm_bsdauth_respond(void *ctx, u_int numresponses, char **responses)
982 {
983 Buffer m;
984 int authok;
985
986 debug3("%s: entering", __func__);
987 if (numresponses != 1)
988 return (-1);
989
990 buffer_init(&m);
991 buffer_put_cstring(&m, responses[0]);
992 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHRESPOND, &m);
993
994 mm_request_receive_expect(pmonitor->m_recvfd,
995 MONITOR_ANS_BSDAUTHRESPOND, &m);
996
997 authok = buffer_get_int(&m);
998 buffer_free(&m);
999
1000 return ((authok == 0) ? -1 : 0);
1001 }
1002
1003 #ifdef SKEY
1004 int
mm_skey_query(void * ctx,char ** name,char ** infotxt,u_int * numprompts,char *** prompts,u_int ** echo_on)1005 mm_skey_query(void *ctx, char **name, char **infotxt,
1006 u_int *numprompts, char ***prompts, u_int **echo_on)
1007 {
1008 Buffer m;
1009 u_int success;
1010 char *challenge;
1011
1012 debug3("%s: entering", __func__);
1013
1014 buffer_init(&m);
1015 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SKEYQUERY, &m);
1016
1017 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SKEYQUERY,
1018 &m);
1019 success = buffer_get_int(&m);
1020 if (success == 0) {
1021 debug3("%s: no challenge", __func__);
1022 buffer_free(&m);
1023 return (-1);
1024 }
1025
1026 /* Get the challenge, and format the response */
1027 challenge = buffer_get_string(&m, NULL);
1028 buffer_free(&m);
1029
1030 debug3("%s: received challenge: %s", __func__, challenge);
1031
1032 mm_chall_setup(name, infotxt, numprompts, prompts, echo_on);
1033
1034 xasprintf(*prompts, "%s%s", challenge, SKEY_PROMPT);
1035 free(challenge);
1036
1037 return (0);
1038 }
1039
1040 int
mm_skey_respond(void * ctx,u_int numresponses,char ** responses)1041 mm_skey_respond(void *ctx, u_int numresponses, char **responses)
1042 {
1043 Buffer m;
1044 int authok;
1045
1046 debug3("%s: entering", __func__);
1047 if (numresponses != 1)
1048 return (-1);
1049
1050 buffer_init(&m);
1051 buffer_put_cstring(&m, responses[0]);
1052 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SKEYRESPOND, &m);
1053
1054 mm_request_receive_expect(pmonitor->m_recvfd,
1055 MONITOR_ANS_SKEYRESPOND, &m);
1056
1057 authok = buffer_get_int(&m);
1058 buffer_free(&m);
1059
1060 return ((authok == 0) ? -1 : 0);
1061 }
1062 #endif /* SKEY */
1063
1064 void
mm_ssh1_session_id(u_char session_id[16])1065 mm_ssh1_session_id(u_char session_id[16])
1066 {
1067 Buffer m;
1068 int i;
1069
1070 debug3("%s entering", __func__);
1071
1072 buffer_init(&m);
1073 for (i = 0; i < 16; i++)
1074 buffer_put_char(&m, session_id[i]);
1075
1076 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SESSID, &m);
1077 buffer_free(&m);
1078 }
1079
1080 int
mm_auth_rsa_key_allowed(struct passwd * pw,BIGNUM * client_n,Key ** rkey)1081 mm_auth_rsa_key_allowed(struct passwd *pw, BIGNUM *client_n, Key **rkey)
1082 {
1083 Buffer m;
1084 Key *key;
1085 u_char *blob;
1086 u_int blen;
1087 int allowed = 0, have_forced = 0;
1088
1089 debug3("%s entering", __func__);
1090
1091 buffer_init(&m);
1092 buffer_put_bignum2(&m, client_n);
1093
1094 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSAKEYALLOWED, &m);
1095 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSAKEYALLOWED, &m);
1096
1097 allowed = buffer_get_int(&m);
1098
1099 /* fake forced command */
1100 auth_clear_options();
1101 have_forced = buffer_get_int(&m);
1102 forced_command = have_forced ? xstrdup("true") : NULL;
1103
1104 if (allowed && rkey != NULL) {
1105 blob = buffer_get_string(&m, &blen);
1106 if ((key = key_from_blob(blob, blen)) == NULL)
1107 fatal("%s: key_from_blob failed", __func__);
1108 *rkey = key;
1109 free(blob);
1110 }
1111 buffer_free(&m);
1112
1113 return (allowed);
1114 }
1115
1116 BIGNUM *
mm_auth_rsa_generate_challenge(Key * key)1117 mm_auth_rsa_generate_challenge(Key *key)
1118 {
1119 Buffer m;
1120 BIGNUM *challenge;
1121 u_char *blob;
1122 u_int blen;
1123
1124 debug3("%s entering", __func__);
1125
1126 if ((challenge = BN_new()) == NULL)
1127 fatal("%s: BN_new failed", __func__);
1128
1129 key->type = KEY_RSA; /* XXX cheat for key_to_blob */
1130 if (key_to_blob(key, &blob, &blen) == 0)
1131 fatal("%s: key_to_blob failed", __func__);
1132 key->type = KEY_RSA1;
1133
1134 buffer_init(&m);
1135 buffer_put_string(&m, blob, blen);
1136 free(blob);
1137
1138 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSACHALLENGE, &m);
1139 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSACHALLENGE, &m);
1140
1141 buffer_get_bignum2(&m, challenge);
1142 buffer_free(&m);
1143
1144 return (challenge);
1145 }
1146
1147 int
mm_auth_rsa_verify_response(Key * key,BIGNUM * p,u_char response[16])1148 mm_auth_rsa_verify_response(Key *key, BIGNUM *p, u_char response[16])
1149 {
1150 Buffer m;
1151 u_char *blob;
1152 u_int blen;
1153 int success = 0;
1154
1155 debug3("%s entering", __func__);
1156
1157 key->type = KEY_RSA; /* XXX cheat for key_to_blob */
1158 if (key_to_blob(key, &blob, &blen) == 0)
1159 fatal("%s: key_to_blob failed", __func__);
1160 key->type = KEY_RSA1;
1161
1162 buffer_init(&m);
1163 buffer_put_string(&m, blob, blen);
1164 buffer_put_string(&m, response, 16);
1165 free(blob);
1166
1167 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_RSARESPONSE, &m);
1168 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_RSARESPONSE, &m);
1169
1170 success = buffer_get_int(&m);
1171 buffer_free(&m);
1172
1173 return (success);
1174 }
1175
1176 #ifdef SSH_AUDIT_EVENTS
1177 void
mm_audit_event(ssh_audit_event_t event)1178 mm_audit_event(ssh_audit_event_t event)
1179 {
1180 Buffer m;
1181
1182 debug3("%s entering", __func__);
1183
1184 buffer_init(&m);
1185 buffer_put_int(&m, event);
1186
1187 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUDIT_EVENT, &m);
1188 buffer_free(&m);
1189 }
1190
1191 void
mm_audit_run_command(const char * command)1192 mm_audit_run_command(const char *command)
1193 {
1194 Buffer m;
1195
1196 debug3("%s entering command %s", __func__, command);
1197
1198 buffer_init(&m);
1199 buffer_put_cstring(&m, command);
1200
1201 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUDIT_COMMAND, &m);
1202 buffer_free(&m);
1203 }
1204 #endif /* SSH_AUDIT_EVENTS */
1205
1206 #ifdef GSSAPI
1207 OM_uint32
mm_ssh_gssapi_server_ctx(Gssctxt ** ctx,gss_OID goid)1208 mm_ssh_gssapi_server_ctx(Gssctxt **ctx, gss_OID goid)
1209 {
1210 Buffer m;
1211 OM_uint32 major;
1212
1213 /* Client doesn't get to see the context */
1214 *ctx = NULL;
1215
1216 buffer_init(&m);
1217 buffer_put_string(&m, goid->elements, goid->length);
1218
1219 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSETUP, &m);
1220 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSETUP, &m);
1221
1222 major = buffer_get_int(&m);
1223
1224 buffer_free(&m);
1225 return (major);
1226 }
1227
1228 OM_uint32
mm_ssh_gssapi_accept_ctx(Gssctxt * ctx,gss_buffer_desc * in,gss_buffer_desc * out,OM_uint32 * flags)1229 mm_ssh_gssapi_accept_ctx(Gssctxt *ctx, gss_buffer_desc *in,
1230 gss_buffer_desc *out, OM_uint32 *flags)
1231 {
1232 Buffer m;
1233 OM_uint32 major;
1234 u_int len;
1235
1236 buffer_init(&m);
1237 buffer_put_string(&m, in->value, in->length);
1238
1239 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSTEP, &m);
1240 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSTEP, &m);
1241
1242 major = buffer_get_int(&m);
1243 out->value = buffer_get_string(&m, &len);
1244 out->length = len;
1245 if (flags)
1246 *flags = buffer_get_int(&m);
1247
1248 buffer_free(&m);
1249
1250 return (major);
1251 }
1252
1253 OM_uint32
mm_ssh_gssapi_checkmic(Gssctxt * ctx,gss_buffer_t gssbuf,gss_buffer_t gssmic)1254 mm_ssh_gssapi_checkmic(Gssctxt *ctx, gss_buffer_t gssbuf, gss_buffer_t gssmic)
1255 {
1256 Buffer m;
1257 OM_uint32 major;
1258
1259 buffer_init(&m);
1260 buffer_put_string(&m, gssbuf->value, gssbuf->length);
1261 buffer_put_string(&m, gssmic->value, gssmic->length);
1262
1263 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSCHECKMIC, &m);
1264 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSCHECKMIC,
1265 &m);
1266
1267 major = buffer_get_int(&m);
1268 buffer_free(&m);
1269 return(major);
1270 }
1271
1272 int
mm_ssh_gssapi_userok(char * user)1273 mm_ssh_gssapi_userok(char *user)
1274 {
1275 Buffer m;
1276 int authenticated = 0;
1277
1278 buffer_init(&m);
1279
1280 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSUSEROK, &m);
1281 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSUSEROK,
1282 &m);
1283
1284 authenticated = buffer_get_int(&m);
1285
1286 buffer_free(&m);
1287 debug3("%s: user %sauthenticated",__func__, authenticated ? "" : "not ");
1288 return (authenticated);
1289 }
1290 #endif /* GSSAPI */
1291
1292