1 /* $OpenBSD: monitor_wrap.c,v 1.129 2023/12/18 14:45:49 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
32 #include <errno.h>
33 #include <pwd.h>
34 #include <signal.h>
35 #include <stdio.h>
36 #include <string.h>
37 #include <stdarg.h>
38 #include <unistd.h>
39
40 #ifdef WITH_OPENSSL
41 #include <openssl/bn.h>
42 #include <openssl/dh.h>
43 #endif
44
45 #include "xmalloc.h"
46 #include "ssh.h"
47 #ifdef WITH_OPENSSL
48 #include "dh.h"
49 #endif
50 #include "sshbuf.h"
51 #include "sshkey.h"
52 #include "cipher.h"
53 #include "kex.h"
54 #include "hostfile.h"
55 #include "auth.h"
56 #include "auth-options.h"
57 #include "packet.h"
58 #include "mac.h"
59 #include "log.h"
60 #include "monitor.h"
61 #ifdef GSSAPI
62 #include "ssh-gss.h"
63 #endif
64 #include "monitor_wrap.h"
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
73 #include "ssherr.h"
74
75 /* Imports */
76 extern struct monitor *pmonitor;
77 extern struct sshbuf *loginmsg;
78 extern ServerOptions options;
79
80 void
mm_log_handler(LogLevel level,int forced,const char * msg,void * ctx)81 mm_log_handler(LogLevel level, int forced, const char *msg, void *ctx)
82 {
83 struct sshbuf *log_msg;
84 struct monitor *mon = (struct monitor *)ctx;
85 int r;
86 size_t len;
87
88 if (mon->m_log_sendfd == -1)
89 fatal_f("no log channel");
90
91 if ((log_msg = sshbuf_new()) == NULL)
92 fatal_f("sshbuf_new failed");
93
94 if ((r = sshbuf_put_u32(log_msg, 0)) != 0 || /* length; filled below */
95 (r = sshbuf_put_u32(log_msg, level)) != 0 ||
96 (r = sshbuf_put_u32(log_msg, forced)) != 0 ||
97 (r = sshbuf_put_cstring(log_msg, msg)) != 0)
98 fatal_fr(r, "assemble");
99 if ((len = sshbuf_len(log_msg)) < 4 || len > 0xffffffff)
100 fatal_f("bad length %zu", len);
101 POKE_U32(sshbuf_mutable_ptr(log_msg), len - 4);
102 if (atomicio(vwrite, mon->m_log_sendfd,
103 sshbuf_mutable_ptr(log_msg), len) != len)
104 fatal_f("write: %s", strerror(errno));
105 sshbuf_free(log_msg);
106 }
107
108 int
mm_is_monitor(void)109 mm_is_monitor(void)
110 {
111 /*
112 * m_pid is only set in the privileged part, and
113 * points to the unprivileged child.
114 */
115 return (pmonitor && pmonitor->m_pid > 0);
116 }
117
118 void
mm_request_send(int sock,enum monitor_reqtype type,struct sshbuf * m)119 mm_request_send(int sock, enum monitor_reqtype type, struct sshbuf *m)
120 {
121 size_t mlen = sshbuf_len(m);
122 u_char buf[5];
123
124 debug3_f("entering, type %d", type);
125
126 if (mlen >= 0xffffffff)
127 fatal_f("bad length %zu", mlen);
128 POKE_U32(buf, mlen + 1);
129 buf[4] = (u_char) type; /* 1st byte of payload is mesg-type */
130 if (atomicio(vwrite, sock, buf, sizeof(buf)) != sizeof(buf))
131 fatal_f("write: %s", strerror(errno));
132 if (atomicio(vwrite, sock, sshbuf_mutable_ptr(m), mlen) != mlen)
133 fatal_f("write: %s", strerror(errno));
134 }
135
136 void
mm_request_receive(int sock,struct sshbuf * m)137 mm_request_receive(int sock, struct sshbuf *m)
138 {
139 u_char buf[4], *p = NULL;
140 u_int msg_len;
141 int r;
142
143 debug3_f("entering");
144
145 if (atomicio(read, sock, buf, sizeof(buf)) != sizeof(buf)) {
146 if (errno == EPIPE)
147 cleanup_exit(255);
148 fatal_f("read: %s", strerror(errno));
149 }
150 msg_len = PEEK_U32(buf);
151 if (msg_len > 256 * 1024)
152 fatal_f("read: bad msg_len %d", msg_len);
153 sshbuf_reset(m);
154 if ((r = sshbuf_reserve(m, msg_len, &p)) != 0)
155 fatal_fr(r, "reserve");
156 if (atomicio(read, sock, p, msg_len) != msg_len)
157 fatal_f("read: %s", strerror(errno));
158 }
159
160 void
mm_request_receive_expect(int sock,enum monitor_reqtype type,struct sshbuf * m)161 mm_request_receive_expect(int sock, enum monitor_reqtype type, struct sshbuf *m)
162 {
163 u_char rtype;
164 int r;
165
166 debug3_f("entering, type %d", type);
167
168 mm_request_receive(sock, m);
169 if ((r = sshbuf_get_u8(m, &rtype)) != 0)
170 fatal_fr(r, "parse");
171 if (rtype != type)
172 fatal_f("read: rtype %d != type %d", rtype, type);
173 }
174
175 #ifdef WITH_OPENSSL
176 DH *
mm_choose_dh(int min,int nbits,int max)177 mm_choose_dh(int min, int nbits, int max)
178 {
179 BIGNUM *p, *g;
180 int r;
181 u_char success = 0;
182 struct sshbuf *m;
183
184 if ((m = sshbuf_new()) == NULL)
185 fatal_f("sshbuf_new failed");
186 if ((r = sshbuf_put_u32(m, min)) != 0 ||
187 (r = sshbuf_put_u32(m, nbits)) != 0 ||
188 (r = sshbuf_put_u32(m, max)) != 0)
189 fatal_fr(r, "assemble");
190
191 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_MODULI, m);
192
193 debug3_f("waiting for MONITOR_ANS_MODULI");
194 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_MODULI, m);
195
196 if ((r = sshbuf_get_u8(m, &success)) != 0)
197 fatal_fr(r, "parse success");
198 if (success == 0)
199 fatal_f("MONITOR_ANS_MODULI failed");
200
201 if ((r = sshbuf_get_bignum2(m, &p)) != 0 ||
202 (r = sshbuf_get_bignum2(m, &g)) != 0)
203 fatal_fr(r, "parse group");
204
205 debug3_f("remaining %zu", sshbuf_len(m));
206 sshbuf_free(m);
207
208 return (dh_new_group(g, p));
209 }
210 #endif
211
212 int
mm_sshkey_sign(struct ssh * ssh,struct sshkey * key,u_char ** sigp,size_t * lenp,const u_char * data,size_t datalen,const char * hostkey_alg,const char * sk_provider,const char * sk_pin,u_int compat)213 mm_sshkey_sign(struct ssh *ssh, struct sshkey *key, u_char **sigp, size_t *lenp,
214 const u_char *data, size_t datalen, const char *hostkey_alg,
215 const char *sk_provider, const char *sk_pin, u_int compat)
216 {
217 struct kex *kex = *pmonitor->m_pkex;
218 struct sshbuf *m;
219 u_int ndx = kex->host_key_index(key, 0, ssh);
220 int r;
221
222 debug3_f("entering");
223 if ((m = sshbuf_new()) == NULL)
224 fatal_f("sshbuf_new failed");
225 if ((r = sshbuf_put_u32(m, ndx)) != 0 ||
226 (r = sshbuf_put_string(m, data, datalen)) != 0 ||
227 (r = sshbuf_put_cstring(m, hostkey_alg)) != 0 ||
228 (r = sshbuf_put_u32(m, compat)) != 0)
229 fatal_fr(r, "assemble");
230
231 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_SIGN, m);
232
233 debug3_f("waiting for MONITOR_ANS_SIGN");
234 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_SIGN, m);
235 if ((r = sshbuf_get_string(m, sigp, lenp)) != 0)
236 fatal_fr(r, "parse");
237 sshbuf_free(m);
238
239 return (0);
240 }
241
242 #define GETPW(b, id) \
243 do { \
244 if ((r = sshbuf_get_string_direct(b, &p, &len)) != 0) \
245 fatal_fr(r, "parse pw %s", #id); \
246 if (len != sizeof(pw->id)) \
247 fatal_fr(r, "bad length for %s", #id); \
248 memcpy(&pw->id, p, len); \
249 } while (0)
250
251 struct passwd *
mm_getpwnamallow(struct ssh * ssh,const char * username)252 mm_getpwnamallow(struct ssh *ssh, const char *username)
253 {
254 struct sshbuf *m;
255 struct passwd *pw;
256 size_t len;
257 u_int i;
258 ServerOptions *newopts;
259 int r;
260 u_char ok;
261 const u_char *p;
262
263 debug3_f("entering");
264
265 if ((m = sshbuf_new()) == NULL)
266 fatal_f("sshbuf_new failed");
267 if ((r = sshbuf_put_cstring(m, username)) != 0)
268 fatal_fr(r, "assemble");
269
270 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PWNAM, m);
271
272 debug3_f("waiting for MONITOR_ANS_PWNAM");
273 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PWNAM, m);
274
275 if ((r = sshbuf_get_u8(m, &ok)) != 0)
276 fatal_fr(r, "parse success");
277 if (ok == 0) {
278 pw = NULL;
279 goto out;
280 }
281
282 pw = xcalloc(sizeof(*pw), 1);
283 GETPW(m, pw_uid);
284 GETPW(m, pw_gid);
285 GETPW(m, pw_change);
286 GETPW(m, pw_expire);
287 if ((r = sshbuf_get_cstring(m, &pw->pw_name, NULL)) != 0 ||
288 (r = sshbuf_get_cstring(m, &pw->pw_passwd, NULL)) != 0 ||
289 (r = sshbuf_get_cstring(m, &pw->pw_gecos, NULL)) != 0 ||
290 (r = sshbuf_get_cstring(m, &pw->pw_class, NULL)) != 0 ||
291 (r = sshbuf_get_cstring(m, &pw->pw_dir, NULL)) != 0 ||
292 (r = sshbuf_get_cstring(m, &pw->pw_shell, NULL)) != 0)
293 fatal_fr(r, "parse pw");
294
295 out:
296 /* copy options block as a Match directive may have changed some */
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 process_permitopen(ssh, &options);
329 process_channel_timeouts(ssh, &options);
330 kex_set_server_sig_algs(ssh, options.pubkey_accepted_algos);
331 free(newopts);
332 sshbuf_free(m);
333
334 return (pw);
335 }
336
337 char *
mm_auth2_read_banner(void)338 mm_auth2_read_banner(void)
339 {
340 struct sshbuf *m;
341 char *banner;
342 int r;
343
344 debug3_f("entering");
345
346 if ((m = sshbuf_new()) == NULL)
347 fatal_f("sshbuf_new failed");
348 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTH2_READ_BANNER, m);
349 sshbuf_reset(m);
350
351 mm_request_receive_expect(pmonitor->m_recvfd,
352 MONITOR_ANS_AUTH2_READ_BANNER, m);
353 if ((r = sshbuf_get_cstring(m, &banner, NULL)) != 0)
354 fatal_fr(r, "parse");
355 sshbuf_free(m);
356
357 /* treat empty banner as missing banner */
358 if (strlen(banner) == 0) {
359 free(banner);
360 banner = NULL;
361 }
362 return (banner);
363 }
364
365 /* Inform the privileged process about service and style */
366
367 void
mm_inform_authserv(char * service,char * style)368 mm_inform_authserv(char *service, char *style)
369 {
370 struct sshbuf *m;
371 int r;
372
373 debug3_f("entering");
374
375 if ((m = sshbuf_new()) == NULL)
376 fatal_f("sshbuf_new failed");
377 if ((r = sshbuf_put_cstring(m, service)) != 0 ||
378 (r = sshbuf_put_cstring(m, style ? style : "")) != 0)
379 fatal_fr(r, "assemble");
380
381 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHSERV, m);
382
383 sshbuf_free(m);
384 }
385
386 /* Do the password authentication */
387 int
mm_auth_password(struct ssh * ssh,char * password)388 mm_auth_password(struct ssh *ssh, char *password)
389 {
390 struct sshbuf *m;
391 int r, authenticated = 0;
392
393 debug3_f("entering");
394
395 if ((m = sshbuf_new()) == NULL)
396 fatal_f("sshbuf_new failed");
397 if ((r = sshbuf_put_cstring(m, password)) != 0)
398 fatal_fr(r, "assemble");
399 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_AUTHPASSWORD, m);
400
401 debug3_f("waiting for MONITOR_ANS_AUTHPASSWORD");
402 mm_request_receive_expect(pmonitor->m_recvfd,
403 MONITOR_ANS_AUTHPASSWORD, m);
404
405 if ((r = sshbuf_get_u32(m, &authenticated)) != 0)
406 fatal_fr(r, "parse");
407
408 sshbuf_free(m);
409
410 debug3_f("user %sauthenticated", authenticated ? "" : "not ");
411 return (authenticated);
412 }
413
414 int
mm_user_key_allowed(struct ssh * ssh,struct passwd * pw,struct sshkey * key,int pubkey_auth_attempt,struct sshauthopt ** authoptp)415 mm_user_key_allowed(struct ssh *ssh, struct passwd *pw, struct sshkey *key,
416 int pubkey_auth_attempt, struct sshauthopt **authoptp)
417 {
418 return (mm_key_allowed(MM_USERKEY, NULL, NULL, key,
419 pubkey_auth_attempt, authoptp));
420 }
421
422 int
mm_hostbased_key_allowed(struct ssh * ssh,struct passwd * pw,const char * user,const char * host,struct sshkey * key)423 mm_hostbased_key_allowed(struct ssh *ssh, struct passwd *pw,
424 const char *user, const char *host, struct sshkey *key)
425 {
426 return (mm_key_allowed(MM_HOSTKEY, user, host, key, 0, NULL));
427 }
428
429 int
mm_key_allowed(enum mm_keytype type,const char * user,const char * host,struct sshkey * key,int pubkey_auth_attempt,struct sshauthopt ** authoptp)430 mm_key_allowed(enum mm_keytype type, const char *user, const char *host,
431 struct sshkey *key, int pubkey_auth_attempt, struct sshauthopt **authoptp)
432 {
433 struct sshbuf *m;
434 int r, allowed = 0;
435 struct sshauthopt *opts = NULL;
436
437 debug3_f("entering");
438
439 if (authoptp != NULL)
440 *authoptp = NULL;
441
442 if ((m = sshbuf_new()) == NULL)
443 fatal_f("sshbuf_new failed");
444 if ((r = sshbuf_put_u32(m, type)) != 0 ||
445 (r = sshbuf_put_cstring(m, user ? user : "")) != 0 ||
446 (r = sshbuf_put_cstring(m, host ? host : "")) != 0 ||
447 (r = sshkey_puts(key, m)) != 0 ||
448 (r = sshbuf_put_u32(m, pubkey_auth_attempt)) != 0)
449 fatal_fr(r, "assemble");
450
451 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYALLOWED, m);
452
453 debug3_f("waiting for MONITOR_ANS_KEYALLOWED");
454 mm_request_receive_expect(pmonitor->m_recvfd,
455 MONITOR_ANS_KEYALLOWED, m);
456
457 if ((r = sshbuf_get_u32(m, &allowed)) != 0)
458 fatal_fr(r, "parse");
459 if (allowed && type == MM_USERKEY &&
460 (r = sshauthopt_deserialise(m, &opts)) != 0)
461 fatal_fr(r, "sshauthopt_deserialise");
462 sshbuf_free(m);
463
464 if (authoptp != NULL) {
465 *authoptp = opts;
466 opts = NULL;
467 }
468 sshauthopt_free(opts);
469
470 return allowed;
471 }
472
473 /*
474 * This key verify needs to send the key type along, because the
475 * privileged parent makes the decision if the key is allowed
476 * for authentication.
477 */
478
479 int
mm_sshkey_verify(const struct sshkey * key,const u_char * sig,size_t siglen,const u_char * data,size_t datalen,const char * sigalg,u_int compat,struct sshkey_sig_details ** sig_detailsp)480 mm_sshkey_verify(const struct sshkey *key, const u_char *sig, size_t siglen,
481 const u_char *data, size_t datalen, const char *sigalg, u_int compat,
482 struct sshkey_sig_details **sig_detailsp)
483 {
484 struct sshbuf *m;
485 u_int encoded_ret = 0;
486 int r;
487 u_char sig_details_present, flags;
488 u_int counter;
489
490 debug3_f("entering");
491
492 if (sig_detailsp != NULL)
493 *sig_detailsp = NULL;
494 if ((m = sshbuf_new()) == NULL)
495 fatal_f("sshbuf_new failed");
496 if ((r = sshkey_puts(key, m)) != 0 ||
497 (r = sshbuf_put_string(m, sig, siglen)) != 0 ||
498 (r = sshbuf_put_string(m, data, datalen)) != 0 ||
499 (r = sshbuf_put_cstring(m, sigalg == NULL ? "" : sigalg)) != 0)
500 fatal_fr(r, "assemble");
501
502 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_KEYVERIFY, m);
503
504 debug3_f("waiting for MONITOR_ANS_KEYVERIFY");
505 mm_request_receive_expect(pmonitor->m_recvfd,
506 MONITOR_ANS_KEYVERIFY, m);
507
508 if ((r = sshbuf_get_u32(m, &encoded_ret)) != 0 ||
509 (r = sshbuf_get_u8(m, &sig_details_present)) != 0)
510 fatal_fr(r, "parse");
511 if (sig_details_present && encoded_ret == 0) {
512 if ((r = sshbuf_get_u32(m, &counter)) != 0 ||
513 (r = sshbuf_get_u8(m, &flags)) != 0)
514 fatal_fr(r, "parse sig_details");
515 if (sig_detailsp != NULL) {
516 *sig_detailsp = xcalloc(1, sizeof(**sig_detailsp));
517 (*sig_detailsp)->sk_counter = counter;
518 (*sig_detailsp)->sk_flags = flags;
519 }
520 }
521
522 sshbuf_free(m);
523
524 if (encoded_ret != 0)
525 return SSH_ERR_SIGNATURE_INVALID;
526 return 0;
527 }
528
529 void
mm_send_keystate(struct ssh * ssh,struct monitor * monitor)530 mm_send_keystate(struct ssh *ssh, struct monitor *monitor)
531 {
532 struct sshbuf *m;
533 int r;
534
535 if ((m = sshbuf_new()) == NULL)
536 fatal_f("sshbuf_new failed");
537 if ((r = ssh_packet_get_state(ssh, m)) != 0)
538 fatal_fr(r, "ssh_packet_get_state");
539 mm_request_send(monitor->m_recvfd, MONITOR_REQ_KEYEXPORT, m);
540 debug3_f("Finished sending state");
541 sshbuf_free(m);
542 }
543
544 int
mm_pty_allocate(int * ptyfd,int * ttyfd,char * namebuf,size_t namebuflen)545 mm_pty_allocate(int *ptyfd, int *ttyfd, char *namebuf, size_t namebuflen)
546 {
547 struct sshbuf *m;
548 char *p, *msg;
549 int success = 0, tmp1 = -1, tmp2 = -1, r;
550
551 /* Kludge: ensure there are fds free to receive the pty/tty */
552 if ((tmp1 = dup(pmonitor->m_recvfd)) == -1 ||
553 (tmp2 = dup(pmonitor->m_recvfd)) == -1) {
554 error_f("cannot allocate fds for pty");
555 if (tmp1 >= 0)
556 close(tmp1);
557 return 0;
558 }
559 close(tmp1);
560 close(tmp2);
561
562 if ((m = sshbuf_new()) == NULL)
563 fatal_f("sshbuf_new failed");
564 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTY, m);
565
566 debug3_f("waiting for MONITOR_ANS_PTY");
567 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_PTY, m);
568
569 if ((r = sshbuf_get_u32(m, &success)) != 0)
570 fatal_fr(r, "parse success");
571 if (success == 0) {
572 debug3_f("pty alloc failed");
573 sshbuf_free(m);
574 return (0);
575 }
576 if ((r = sshbuf_get_cstring(m, &p, NULL)) != 0 ||
577 (r = sshbuf_get_cstring(m, &msg, NULL)) != 0)
578 fatal_fr(r, "parse");
579 sshbuf_free(m);
580
581 strlcpy(namebuf, p, namebuflen); /* Possible truncation */
582 free(p);
583
584 if ((r = sshbuf_put(loginmsg, msg, strlen(msg))) != 0)
585 fatal_fr(r, "put loginmsg");
586 free(msg);
587
588 if ((*ptyfd = mm_receive_fd(pmonitor->m_recvfd)) == -1 ||
589 (*ttyfd = mm_receive_fd(pmonitor->m_recvfd)) == -1)
590 fatal_f("receive fds failed");
591
592 /* Success */
593 return (1);
594 }
595
596 void
mm_session_pty_cleanup2(Session * s)597 mm_session_pty_cleanup2(Session *s)
598 {
599 struct sshbuf *m;
600 int r;
601
602 if (s->ttyfd == -1)
603 return;
604 if ((m = sshbuf_new()) == NULL)
605 fatal_f("sshbuf_new failed");
606 if ((r = sshbuf_put_cstring(m, s->tty)) != 0)
607 fatal_fr(r, "assmble");
608 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_PTYCLEANUP, m);
609 sshbuf_free(m);
610
611 /* closed dup'ed master */
612 if (s->ptymaster != -1 && close(s->ptymaster) == -1)
613 error("close(s->ptymaster/%d): %s",
614 s->ptymaster, strerror(errno));
615
616 /* unlink pty from session */
617 s->ttyfd = -1;
618 }
619
620 /* Request process termination */
621
622 void
mm_terminate(void)623 mm_terminate(void)
624 {
625 struct sshbuf *m;
626
627 if ((m = sshbuf_new()) == NULL)
628 fatal_f("sshbuf_new failed");
629 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_TERM, m);
630 sshbuf_free(m);
631 }
632
633 static void
mm_chall_setup(char ** name,char ** infotxt,u_int * numprompts,char *** prompts,u_int ** echo_on)634 mm_chall_setup(char **name, char **infotxt, u_int *numprompts,
635 char ***prompts, u_int **echo_on)
636 {
637 *name = xstrdup("");
638 *infotxt = xstrdup("");
639 *numprompts = 1;
640 *prompts = xcalloc(*numprompts, sizeof(char *));
641 *echo_on = xcalloc(*numprompts, sizeof(u_int));
642 (*echo_on)[0] = 0;
643 }
644
645 int
mm_bsdauth_query(void * ctx,char ** name,char ** infotxt,u_int * numprompts,char *** prompts,u_int ** echo_on)646 mm_bsdauth_query(void *ctx, char **name, char **infotxt,
647 u_int *numprompts, char ***prompts, u_int **echo_on)
648 {
649 struct sshbuf *m;
650 u_int success;
651 char *challenge;
652 int r;
653
654 debug3_f("entering");
655
656 if ((m = sshbuf_new()) == NULL)
657 fatal_f("sshbuf_new failed");
658 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHQUERY, m);
659
660 mm_request_receive_expect(pmonitor->m_recvfd,
661 MONITOR_ANS_BSDAUTHQUERY, m);
662 if ((r = sshbuf_get_u32(m, &success)) != 0)
663 fatal_fr(r, "parse success");
664 if (success == 0) {
665 debug3_f("no challenge");
666 sshbuf_free(m);
667 return (-1);
668 }
669
670 /* Get the challenge, and format the response */
671 if ((r = sshbuf_get_cstring(m, &challenge, NULL)) != 0)
672 fatal_fr(r, "parse challenge");
673 sshbuf_free(m);
674
675 mm_chall_setup(name, infotxt, numprompts, prompts, echo_on);
676 (*prompts)[0] = challenge;
677
678 debug3_f("received challenge: %s", challenge);
679
680 return (0);
681 }
682
683 int
mm_bsdauth_respond(void * ctx,u_int numresponses,char ** responses)684 mm_bsdauth_respond(void *ctx, u_int numresponses, char **responses)
685 {
686 struct sshbuf *m;
687 int r, authok;
688
689 debug3_f("entering");
690 if (numresponses != 1)
691 return (-1);
692
693 if ((m = sshbuf_new()) == NULL)
694 fatal_f("sshbuf_new failed");
695 if ((r = sshbuf_put_cstring(m, responses[0])) != 0)
696 fatal_fr(r, "assemble");
697 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_BSDAUTHRESPOND, m);
698
699 mm_request_receive_expect(pmonitor->m_recvfd,
700 MONITOR_ANS_BSDAUTHRESPOND, m);
701
702 if ((r = sshbuf_get_u32(m, &authok)) != 0)
703 fatal_fr(r, "parse");
704 sshbuf_free(m);
705
706 return ((authok == 0) ? -1 : 0);
707 }
708
709 #ifdef GSSAPI
710 OM_uint32
mm_ssh_gssapi_server_ctx(Gssctxt ** ctx,gss_OID goid)711 mm_ssh_gssapi_server_ctx(Gssctxt **ctx, gss_OID goid)
712 {
713 struct sshbuf *m;
714 OM_uint32 major;
715 int r;
716
717 /* Client doesn't get to see the context */
718 *ctx = NULL;
719
720 if ((m = sshbuf_new()) == NULL)
721 fatal_f("sshbuf_new failed");
722 if ((r = sshbuf_put_string(m, goid->elements, goid->length)) != 0)
723 fatal_fr(r, "assemble");
724
725 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSETUP, m);
726 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSETUP, m);
727
728 if ((r = sshbuf_get_u32(m, &major)) != 0)
729 fatal_fr(r, "parse");
730
731 sshbuf_free(m);
732 return (major);
733 }
734
735 OM_uint32
mm_ssh_gssapi_accept_ctx(Gssctxt * ctx,gss_buffer_desc * in,gss_buffer_desc * out,OM_uint32 * flagsp)736 mm_ssh_gssapi_accept_ctx(Gssctxt *ctx, gss_buffer_desc *in,
737 gss_buffer_desc *out, OM_uint32 *flagsp)
738 {
739 struct sshbuf *m;
740 OM_uint32 major;
741 u_int flags;
742 int r;
743
744 if ((m = sshbuf_new()) == NULL)
745 fatal_f("sshbuf_new failed");
746 if ((r = sshbuf_put_string(m, in->value, in->length)) != 0)
747 fatal_fr(r, "assemble");
748
749 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSSTEP, m);
750 mm_request_receive_expect(pmonitor->m_recvfd, MONITOR_ANS_GSSSTEP, m);
751
752 if ((r = sshbuf_get_u32(m, &major)) != 0 ||
753 (r = ssh_gssapi_get_buffer_desc(m, out)) != 0)
754 fatal_fr(r, "parse");
755 if (flagsp != NULL) {
756 if ((r = sshbuf_get_u32(m, &flags)) != 0)
757 fatal_fr(r, "parse flags");
758 *flagsp = flags;
759 }
760
761 sshbuf_free(m);
762
763 return (major);
764 }
765
766 OM_uint32
mm_ssh_gssapi_checkmic(Gssctxt * ctx,gss_buffer_t gssbuf,gss_buffer_t gssmic)767 mm_ssh_gssapi_checkmic(Gssctxt *ctx, gss_buffer_t gssbuf, gss_buffer_t gssmic)
768 {
769 struct sshbuf *m;
770 OM_uint32 major;
771 int r;
772
773 if ((m = sshbuf_new()) == NULL)
774 fatal_f("sshbuf_new failed");
775 if ((r = sshbuf_put_string(m, gssbuf->value, gssbuf->length)) != 0 ||
776 (r = sshbuf_put_string(m, gssmic->value, gssmic->length)) != 0)
777 fatal_fr(r, "assemble");
778
779 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSCHECKMIC, m);
780 mm_request_receive_expect(pmonitor->m_recvfd,
781 MONITOR_ANS_GSSCHECKMIC, m);
782
783 if ((r = sshbuf_get_u32(m, &major)) != 0)
784 fatal_fr(r, "parse");
785 sshbuf_free(m);
786 return(major);
787 }
788
789 int
mm_ssh_gssapi_userok(char * user)790 mm_ssh_gssapi_userok(char *user)
791 {
792 struct sshbuf *m;
793 int r, authenticated = 0;
794
795 if ((m = sshbuf_new()) == NULL)
796 fatal_f("sshbuf_new failed");
797
798 mm_request_send(pmonitor->m_recvfd, MONITOR_REQ_GSSUSEROK, m);
799 mm_request_receive_expect(pmonitor->m_recvfd,
800 MONITOR_ANS_GSSUSEROK, m);
801
802 if ((r = sshbuf_get_u32(m, &authenticated)) != 0)
803 fatal_fr(r, "parse");
804
805 sshbuf_free(m);
806 debug3_f("user %sauthenticated", authenticated ? "" : "not ");
807 return (authenticated);
808 }
809 #endif /* GSSAPI */
810