1 /* $OpenBSD: monitor.c,v 1.145 2015/02/20 22:17:21 djm Exp $ */
3 * Copyright 2002 Niels Provos <provos@citi.umich.edu>
4 * Copyright 2002 Markus Friedl <markus@openbsd.org>
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
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.
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.
30 #include <sys/types.h>
31 #include <sys/socket.h>
32 #include "openbsd-compat/sys-tree.h"
53 # ifdef HAVE_SYS_POLL_H
54 # include <sys/poll.h>
63 #include <openssl/dh.h>
66 #include "openbsd-compat/sys-queue.h"
77 #ifdef TARGET_OS_MAC /* XXX Broken krb5 headers on Mac */
80 #define TARGET_OS_MAC 1
85 #include "auth-options.h"
95 #include "monitor_mm.h"
99 #include "monitor_wrap.h"
100 #include "monitor_fdpass.h"
109 static Gssctxt *gsscontext = NULL;
113 extern ServerOptions options;
114 extern u_int utmp_len;
115 extern u_char session_id[];
116 extern Buffer auth_debug;
117 extern int auth_debug_init;
118 extern Buffer loginmsg;
120 /* State exported from the child */
121 static struct sshbuf *child_state;
123 /* Functions on the monitor that answer unprivileged requests */
125 int mm_answer_moduli(int, Buffer *);
126 int mm_answer_sign(int, Buffer *);
127 int mm_answer_pwnamallow(int, Buffer *);
128 int mm_answer_auth2_read_banner(int, Buffer *);
129 int mm_answer_authserv(int, Buffer *);
130 int mm_answer_authpassword(int, Buffer *);
131 int mm_answer_bsdauthquery(int, Buffer *);
132 int mm_answer_bsdauthrespond(int, Buffer *);
133 int mm_answer_skeyquery(int, Buffer *);
134 int mm_answer_skeyrespond(int, Buffer *);
135 int mm_answer_keyallowed(int, Buffer *);
136 int mm_answer_keyverify(int, Buffer *);
137 int mm_answer_pty(int, Buffer *);
138 int mm_answer_pty_cleanup(int, Buffer *);
139 int mm_answer_term(int, Buffer *);
140 int mm_answer_rsa_keyallowed(int, Buffer *);
141 int mm_answer_rsa_challenge(int, Buffer *);
142 int mm_answer_rsa_response(int, Buffer *);
143 int mm_answer_sesskey(int, Buffer *);
144 int mm_answer_sessid(int, Buffer *);
147 int mm_answer_pam_start(int, Buffer *);
148 int mm_answer_pam_account(int, Buffer *);
149 int mm_answer_pam_init_ctx(int, Buffer *);
150 int mm_answer_pam_query(int, Buffer *);
151 int mm_answer_pam_respond(int, Buffer *);
152 int mm_answer_pam_free_ctx(int, Buffer *);
156 int mm_answer_gss_setup_ctx(int, Buffer *);
157 int mm_answer_gss_accept_ctx(int, Buffer *);
158 int mm_answer_gss_userok(int, Buffer *);
159 int mm_answer_gss_checkmic(int, Buffer *);
162 #ifdef SSH_AUDIT_EVENTS
163 int mm_answer_audit_event(int, Buffer *);
164 int mm_answer_audit_command(int, Buffer *);
167 static int monitor_read_log(struct monitor *);
169 static Authctxt *authctxt;
172 static BIGNUM *ssh1_challenge = NULL; /* used for ssh1 rsa auth */
175 /* local state for key verify */
176 static u_char *key_blob = NULL;
177 static u_int key_bloblen = 0;
178 static int key_blobtype = MM_NOKEY;
179 static char *hostbased_cuser = NULL;
180 static char *hostbased_chost = NULL;
181 static char *auth_method = "unknown";
182 static char *auth_submethod = NULL;
183 static u_int session_id2_len = 0;
184 static u_char *session_id2 = NULL;
185 static pid_t monitor_child_pid;
188 enum monitor_reqtype type;
190 int (*f)(int, Buffer *);
193 #define MON_ISAUTH 0x0004 /* Required for Authentication */
194 #define MON_AUTHDECIDE 0x0008 /* Decides Authentication */
195 #define MON_ONCE 0x0010 /* Disable after calling */
196 #define MON_ALOG 0x0020 /* Log auth attempt without authenticating */
198 #define MON_AUTH (MON_ISAUTH|MON_AUTHDECIDE)
200 #define MON_PERMIT 0x1000 /* Request is permitted */
202 struct mon_table mon_dispatch_proto20[] = {
204 {MONITOR_REQ_MODULI, MON_ONCE, mm_answer_moduli},
206 {MONITOR_REQ_SIGN, MON_ONCE, mm_answer_sign},
207 {MONITOR_REQ_PWNAM, MON_ONCE, mm_answer_pwnamallow},
208 {MONITOR_REQ_AUTHSERV, MON_ONCE, mm_answer_authserv},
209 {MONITOR_REQ_AUTH2_READ_BANNER, MON_ONCE, mm_answer_auth2_read_banner},
210 {MONITOR_REQ_AUTHPASSWORD, MON_AUTH, mm_answer_authpassword},
212 {MONITOR_REQ_PAM_START, MON_ONCE, mm_answer_pam_start},
213 {MONITOR_REQ_PAM_ACCOUNT, 0, mm_answer_pam_account},
214 {MONITOR_REQ_PAM_INIT_CTX, MON_ISAUTH, mm_answer_pam_init_ctx},
215 {MONITOR_REQ_PAM_QUERY, MON_ISAUTH, mm_answer_pam_query},
216 {MONITOR_REQ_PAM_RESPOND, MON_ISAUTH, mm_answer_pam_respond},
217 {MONITOR_REQ_PAM_FREE_CTX, MON_ONCE|MON_AUTHDECIDE, mm_answer_pam_free_ctx},
219 #ifdef SSH_AUDIT_EVENTS
220 {MONITOR_REQ_AUDIT_EVENT, MON_PERMIT, mm_answer_audit_event},
223 {MONITOR_REQ_BSDAUTHQUERY, MON_ISAUTH, mm_answer_bsdauthquery},
224 {MONITOR_REQ_BSDAUTHRESPOND, MON_AUTH, mm_answer_bsdauthrespond},
227 {MONITOR_REQ_SKEYQUERY, MON_ISAUTH, mm_answer_skeyquery},
228 {MONITOR_REQ_SKEYRESPOND, MON_AUTH, mm_answer_skeyrespond},
230 {MONITOR_REQ_KEYALLOWED, MON_ISAUTH, mm_answer_keyallowed},
231 {MONITOR_REQ_KEYVERIFY, MON_AUTH, mm_answer_keyverify},
233 {MONITOR_REQ_GSSSETUP, MON_ISAUTH, mm_answer_gss_setup_ctx},
234 {MONITOR_REQ_GSSSTEP, MON_ISAUTH, mm_answer_gss_accept_ctx},
235 {MONITOR_REQ_GSSUSEROK, MON_AUTH, mm_answer_gss_userok},
236 {MONITOR_REQ_GSSCHECKMIC, MON_ISAUTH, mm_answer_gss_checkmic},
241 struct mon_table mon_dispatch_postauth20[] = {
243 {MONITOR_REQ_MODULI, 0, mm_answer_moduli},
245 {MONITOR_REQ_SIGN, 0, mm_answer_sign},
246 {MONITOR_REQ_PTY, 0, mm_answer_pty},
247 {MONITOR_REQ_PTYCLEANUP, 0, mm_answer_pty_cleanup},
248 {MONITOR_REQ_TERM, 0, mm_answer_term},
249 #ifdef SSH_AUDIT_EVENTS
250 {MONITOR_REQ_AUDIT_EVENT, MON_PERMIT, mm_answer_audit_event},
251 {MONITOR_REQ_AUDIT_COMMAND, MON_PERMIT, mm_answer_audit_command},
256 struct mon_table mon_dispatch_proto15[] = {
258 {MONITOR_REQ_PWNAM, MON_ONCE, mm_answer_pwnamallow},
259 {MONITOR_REQ_SESSKEY, MON_ONCE, mm_answer_sesskey},
260 {MONITOR_REQ_SESSID, MON_ONCE, mm_answer_sessid},
261 {MONITOR_REQ_AUTHPASSWORD, MON_AUTH, mm_answer_authpassword},
262 {MONITOR_REQ_RSAKEYALLOWED, MON_ISAUTH|MON_ALOG, mm_answer_rsa_keyallowed},
263 {MONITOR_REQ_KEYALLOWED, MON_ISAUTH|MON_ALOG, mm_answer_keyallowed},
264 {MONITOR_REQ_RSACHALLENGE, MON_ONCE, mm_answer_rsa_challenge},
265 {MONITOR_REQ_RSARESPONSE, MON_ONCE|MON_AUTHDECIDE, mm_answer_rsa_response},
267 {MONITOR_REQ_BSDAUTHQUERY, MON_ISAUTH, mm_answer_bsdauthquery},
268 {MONITOR_REQ_BSDAUTHRESPOND, MON_AUTH, mm_answer_bsdauthrespond},
271 {MONITOR_REQ_SKEYQUERY, MON_ISAUTH, mm_answer_skeyquery},
272 {MONITOR_REQ_SKEYRESPOND, MON_AUTH, mm_answer_skeyrespond},
275 {MONITOR_REQ_PAM_START, MON_ONCE, mm_answer_pam_start},
276 {MONITOR_REQ_PAM_ACCOUNT, 0, mm_answer_pam_account},
277 {MONITOR_REQ_PAM_INIT_CTX, MON_ISAUTH, mm_answer_pam_init_ctx},
278 {MONITOR_REQ_PAM_QUERY, MON_ISAUTH, mm_answer_pam_query},
279 {MONITOR_REQ_PAM_RESPOND, MON_ISAUTH, mm_answer_pam_respond},
280 {MONITOR_REQ_PAM_FREE_CTX, MON_ONCE|MON_AUTHDECIDE, mm_answer_pam_free_ctx},
282 #ifdef SSH_AUDIT_EVENTS
283 {MONITOR_REQ_AUDIT_EVENT, MON_PERMIT, mm_answer_audit_event},
285 #endif /* WITH_SSH1 */
289 struct mon_table mon_dispatch_postauth15[] = {
291 {MONITOR_REQ_PTY, MON_ONCE, mm_answer_pty},
292 {MONITOR_REQ_PTYCLEANUP, MON_ONCE, mm_answer_pty_cleanup},
293 {MONITOR_REQ_TERM, 0, mm_answer_term},
294 #ifdef SSH_AUDIT_EVENTS
295 {MONITOR_REQ_AUDIT_EVENT, MON_PERMIT, mm_answer_audit_event},
296 {MONITOR_REQ_AUDIT_COMMAND, MON_PERMIT|MON_ONCE, mm_answer_audit_command},
298 #endif /* WITH_SSH1 */
302 struct mon_table *mon_dispatch;
304 /* Specifies if a certain message is allowed at the moment */
307 monitor_permit(struct mon_table *ent, enum monitor_reqtype type, int permit)
309 while (ent->f != NULL) {
310 if (ent->type == type) {
311 ent->flags &= ~MON_PERMIT;
312 ent->flags |= permit ? MON_PERMIT : 0;
320 monitor_permit_authentications(int permit)
322 struct mon_table *ent = mon_dispatch;
324 while (ent->f != NULL) {
325 if (ent->flags & MON_AUTH) {
326 ent->flags &= ~MON_PERMIT;
327 ent->flags |= permit ? MON_PERMIT : 0;
334 monitor_child_preauth(Authctxt *_authctxt, struct monitor *pmonitor)
336 struct mon_table *ent;
337 int authenticated = 0, partial = 0;
339 debug3("preauth child monitor started");
341 close(pmonitor->m_recvfd);
342 close(pmonitor->m_log_sendfd);
343 pmonitor->m_log_sendfd = pmonitor->m_recvfd = -1;
345 authctxt = _authctxt;
346 memset(authctxt, 0, sizeof(*authctxt));
348 authctxt->loginmsg = &loginmsg;
351 mon_dispatch = mon_dispatch_proto20;
353 /* Permit requests for moduli and signatures */
354 monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
355 monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
357 mon_dispatch = mon_dispatch_proto15;
359 monitor_permit(mon_dispatch, MONITOR_REQ_SESSKEY, 1);
362 /* The first few requests do not require asynchronous access */
363 while (!authenticated) {
365 auth_method = "unknown";
366 auth_submethod = NULL;
367 authenticated = (monitor_read(pmonitor, mon_dispatch, &ent) == 1);
369 /* Special handling for multiple required authentications */
370 if (options.num_auth_methods != 0) {
372 fatal("AuthenticationMethods is not supported"
373 "with SSH protocol 1");
375 !auth2_update_methods_lists(authctxt,
376 auth_method, auth_submethod)) {
377 debug3("%s: method %s: partial", __func__,
385 if (!(ent->flags & MON_AUTHDECIDE))
386 fatal("%s: unexpected authentication from %d",
387 __func__, ent->type);
388 if (authctxt->pw->pw_uid == 0 &&
389 !auth_root_allowed(auth_method))
392 /* PAM needs to perform account checks after auth */
393 if (options.use_pam && authenticated) {
397 mm_request_receive_expect(pmonitor->m_sendfd,
398 MONITOR_REQ_PAM_ACCOUNT, &m);
399 authenticated = mm_answer_pam_account(pmonitor->m_sendfd, &m);
404 if (ent->flags & (MON_AUTHDECIDE|MON_ALOG)) {
405 auth_log(authctxt, authenticated, partial,
406 auth_method, auth_submethod);
408 authctxt->failures++;
412 if (!authctxt->valid)
413 fatal("%s: authenticated invalid user", __func__);
414 if (strcmp(auth_method, "unknown") == 0)
415 fatal("%s: authentication method name unknown", __func__);
417 debug("%s: %s has been authenticated by privileged process",
418 __func__, authctxt->user);
420 mm_get_keystate(pmonitor);
422 /* Drain any buffered messages from the child */
423 while (pmonitor->m_log_recvfd != -1 && monitor_read_log(pmonitor) == 0)
426 close(pmonitor->m_sendfd);
427 close(pmonitor->m_log_recvfd);
428 pmonitor->m_sendfd = pmonitor->m_log_recvfd = -1;
432 monitor_set_child_handler(pid_t pid)
434 monitor_child_pid = pid;
438 monitor_child_handler(int sig)
440 kill(monitor_child_pid, sig);
444 monitor_child_postauth(struct monitor *pmonitor)
446 close(pmonitor->m_recvfd);
447 pmonitor->m_recvfd = -1;
449 monitor_set_child_handler(pmonitor->m_pid);
450 signal(SIGHUP, &monitor_child_handler);
451 signal(SIGTERM, &monitor_child_handler);
452 signal(SIGINT, &monitor_child_handler);
454 signal(SIGXFSZ, SIG_IGN);
458 mon_dispatch = mon_dispatch_postauth20;
460 /* Permit requests for moduli and signatures */
461 monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
462 monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
463 monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1);
465 mon_dispatch = mon_dispatch_postauth15;
466 monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1);
469 monitor_permit(mon_dispatch, MONITOR_REQ_PTY, 1);
470 monitor_permit(mon_dispatch, MONITOR_REQ_PTYCLEANUP, 1);
474 monitor_read(pmonitor, mon_dispatch, NULL);
478 monitor_sync(struct monitor *pmonitor)
480 if (options.compression) {
481 /* The member allocation is not visible, so sync it */
482 mm_share_sync(&pmonitor->m_zlib, &pmonitor->m_zback);
486 /* Allocation functions for zlib */
488 mm_zalloc(struct mm_master *mm, u_int ncount, u_int size)
490 size_t len = (size_t) size * ncount;
493 if (len == 0 || ncount > SIZE_MAX / size)
494 fatal("%s: mm_zalloc(%u, %u)", __func__, ncount, size);
496 address = mm_malloc(mm, len);
502 mm_zfree(struct mm_master *mm, void *address)
504 mm_free(mm, address);
508 monitor_read_log(struct monitor *pmonitor)
514 buffer_init(&logmsg);
517 buffer_append_space(&logmsg, 4);
518 if (atomicio(read, pmonitor->m_log_recvfd,
519 buffer_ptr(&logmsg), buffer_len(&logmsg)) != buffer_len(&logmsg)) {
520 if (errno == EPIPE) {
521 buffer_free(&logmsg);
522 debug("%s: child log fd closed", __func__);
523 close(pmonitor->m_log_recvfd);
524 pmonitor->m_log_recvfd = -1;
527 fatal("%s: log fd read: %s", __func__, strerror(errno));
529 len = buffer_get_int(&logmsg);
530 if (len <= 4 || len > 8192)
531 fatal("%s: invalid log message length %u", __func__, len);
533 /* Read severity, message */
534 buffer_clear(&logmsg);
535 buffer_append_space(&logmsg, len);
536 if (atomicio(read, pmonitor->m_log_recvfd,
537 buffer_ptr(&logmsg), buffer_len(&logmsg)) != buffer_len(&logmsg))
538 fatal("%s: log fd read: %s", __func__, strerror(errno));
541 level = buffer_get_int(&logmsg);
542 msg = buffer_get_string(&logmsg, NULL);
543 if (log_level_name(level) == NULL)
544 fatal("%s: invalid log level %u (corrupted message?)",
546 do_log2(level, "%s [preauth]", msg);
548 buffer_free(&logmsg);
555 monitor_read(struct monitor *pmonitor, struct mon_table *ent,
556 struct mon_table **pent)
561 struct pollfd pfd[2];
564 memset(&pfd, 0, sizeof(pfd));
565 pfd[0].fd = pmonitor->m_sendfd;
566 pfd[0].events = POLLIN;
567 pfd[1].fd = pmonitor->m_log_recvfd;
568 pfd[1].events = pfd[1].fd == -1 ? 0 : POLLIN;
569 if (poll(pfd, pfd[1].fd == -1 ? 1 : 2, -1) == -1) {
570 if (errno == EINTR || errno == EAGAIN)
572 fatal("%s: poll: %s", __func__, strerror(errno));
574 if (pfd[1].revents) {
576 * Drain all log messages before processing next
579 monitor_read_log(pmonitor);
583 break; /* Continues below */
588 mm_request_receive(pmonitor->m_sendfd, &m);
589 type = buffer_get_char(&m);
591 debug3("%s: checking request %d", __func__, type);
593 while (ent->f != NULL) {
594 if (ent->type == type)
599 if (ent->f != NULL) {
600 if (!(ent->flags & MON_PERMIT))
601 fatal("%s: unpermitted request %d", __func__,
603 ret = (*ent->f)(pmonitor->m_sendfd, &m);
606 /* The child may use this request only once, disable it */
607 if (ent->flags & MON_ONCE) {
608 debug2("%s: %d used once, disabling now", __func__,
610 ent->flags &= ~MON_PERMIT;
619 fatal("%s: unsupported request: %d", __func__, type);
625 /* allowed key state */
627 monitor_allowed_key(u_char *blob, u_int bloblen)
629 /* make sure key is allowed */
630 if (key_blob == NULL || key_bloblen != bloblen ||
631 timingsafe_bcmp(key_blob, blob, key_bloblen))
637 monitor_reset_key_state(void)
641 free(hostbased_cuser);
642 free(hostbased_chost);
645 key_blobtype = MM_NOKEY;
646 hostbased_cuser = NULL;
647 hostbased_chost = NULL;
652 mm_answer_moduli(int sock, Buffer *m)
657 min = buffer_get_int(m);
658 want = buffer_get_int(m);
659 max = buffer_get_int(m);
661 debug3("%s: got parameters: %d %d %d",
662 __func__, min, want, max);
663 /* We need to check here, too, in case the child got corrupted */
664 if (max < min || want < min || max < want)
665 fatal("%s: bad parameters: %d %d %d",
666 __func__, min, want, max);
670 dh = choose_dh(min, want, max);
672 buffer_put_char(m, 0);
675 /* Send first bignum */
676 buffer_put_char(m, 1);
677 buffer_put_bignum2(m, dh->p);
678 buffer_put_bignum2(m, dh->g);
682 mm_request_send(sock, MONITOR_ANS_MODULI, m);
688 mm_answer_sign(int sock, Buffer *m)
690 struct ssh *ssh = active_state; /* XXX */
691 extern int auth_sock; /* XXX move to state struct? */
693 struct sshbuf *sigbuf;
696 size_t datlen, siglen;
697 int r, keyid, is_proof = 0;
698 const char proof_req[] = "hostkeys-prove-00@openssh.com";
700 debug3("%s", __func__);
702 if ((r = sshbuf_get_u32(m, &keyid)) != 0 ||
703 (r = sshbuf_get_string(m, &p, &datlen)) != 0)
704 fatal("%s: buffer error: %s", __func__, ssh_err(r));
707 * Supported KEX types use SHA1 (20 bytes), SHA256 (32 bytes),
708 * SHA384 (48 bytes) and SHA512 (64 bytes).
710 * Otherwise, verify the signature request is for a hostkey
713 * XXX perform similar check for KEX signature requests too?
714 * it's not trivial, since what is signed is the hash, rather
715 * than the full kex structure...
717 if (datlen != 20 && datlen != 32 && datlen != 48 && datlen != 64) {
719 * Construct expected hostkey proof and compare it to what
720 * the client sent us.
722 if (session_id2_len == 0) /* hostkeys is never first */
723 fatal("%s: bad data length: %zu", __func__, datlen);
724 if ((key = get_hostkey_public_by_index(keyid, ssh)) == NULL)
725 fatal("%s: no hostkey for index %d", __func__, keyid);
726 if ((sigbuf = sshbuf_new()) == NULL)
727 fatal("%s: sshbuf_new", __func__);
728 if ((r = sshbuf_put_cstring(sigbuf, proof_req)) != 0 ||
729 (r = sshbuf_put_string(sigbuf, session_id2,
730 session_id2_len) != 0) ||
731 (r = sshkey_puts(key, sigbuf)) != 0)
732 fatal("%s: couldn't prepare private key "
733 "proof buffer: %s", __func__, ssh_err(r));
734 if (datlen != sshbuf_len(sigbuf) ||
735 memcmp(p, sshbuf_ptr(sigbuf), sshbuf_len(sigbuf)) != 0)
736 fatal("%s: bad data length: %zu, hostkey proof len %zu",
737 __func__, datlen, sshbuf_len(sigbuf));
742 /* save session id, it will be passed on the first call */
743 if (session_id2_len == 0) {
744 session_id2_len = datlen;
745 session_id2 = xmalloc(session_id2_len);
746 memcpy(session_id2, p, session_id2_len);
749 if ((key = get_hostkey_by_index(keyid)) != NULL) {
750 if ((r = sshkey_sign(key, &signature, &siglen, p, datlen,
752 fatal("%s: sshkey_sign failed: %s",
753 __func__, ssh_err(r));
754 } else if ((key = get_hostkey_public_by_index(keyid, ssh)) != NULL &&
756 if ((r = ssh_agent_sign(auth_sock, key, &signature, &siglen,
757 p, datlen, datafellows)) != 0) {
758 fatal("%s: ssh_agent_sign failed: %s",
759 __func__, ssh_err(r));
762 fatal("%s: no hostkey from index %d", __func__, keyid);
764 debug3("%s: %s signature %p(%zu)", __func__,
765 is_proof ? "KEX" : "hostkey proof", signature, siglen);
768 if ((r = sshbuf_put_string(m, signature, siglen)) != 0)
769 fatal("%s: buffer error: %s", __func__, ssh_err(r));
774 mm_request_send(sock, MONITOR_ANS_SIGN, m);
776 /* Turn on permissions for getpwnam */
777 monitor_permit(mon_dispatch, MONITOR_REQ_PWNAM, 1);
782 /* Retrieves the password entry and also checks if the user is permitted */
785 mm_answer_pwnamallow(int sock, Buffer *m)
788 struct passwd *pwent;
792 debug3("%s", __func__);
794 if (authctxt->attempt++ != 0)
795 fatal("%s: multiple attempts for getpwnam", __func__);
797 username = buffer_get_string(m, NULL);
799 pwent = getpwnamallow(username);
801 authctxt->user = xstrdup(username);
802 setproctitle("%s [priv]", pwent ? username : "unknown");
808 buffer_put_char(m, 0);
809 authctxt->pw = fakepw();
814 authctxt->pw = pwent;
817 buffer_put_char(m, 1);
818 buffer_put_string(m, pwent, sizeof(struct passwd));
819 buffer_put_cstring(m, pwent->pw_name);
820 buffer_put_cstring(m, "*");
821 #ifdef HAVE_STRUCT_PASSWD_PW_GECOS
822 buffer_put_cstring(m, pwent->pw_gecos);
824 #ifdef HAVE_STRUCT_PASSWD_PW_CLASS
825 buffer_put_cstring(m, pwent->pw_class);
827 buffer_put_cstring(m, pwent->pw_dir);
828 buffer_put_cstring(m, pwent->pw_shell);
831 buffer_put_string(m, &options, sizeof(options));
833 #define M_CP_STROPT(x) do { \
834 if (options.x != NULL) \
835 buffer_put_cstring(m, options.x); \
837 #define M_CP_STRARRAYOPT(x, nx) do { \
838 for (i = 0; i < options.nx; i++) \
839 buffer_put_cstring(m, options.x[i]); \
841 /* See comment in servconf.h */
842 COPY_MATCH_STRING_OPTS();
844 #undef M_CP_STRARRAYOPT
846 /* Create valid auth method lists */
847 if (compat20 && auth2_setup_methods_lists(authctxt) != 0) {
849 * The monitor will continue long enough to let the child
850 * run to it's packet_disconnect(), but it must not allow any
851 * authentication to succeed.
853 debug("%s: no valid authentication method lists", __func__);
856 debug3("%s: sending MONITOR_ANS_PWNAM: %d", __func__, allowed);
857 mm_request_send(sock, MONITOR_ANS_PWNAM, m);
859 /* For SSHv1 allow authentication now */
861 monitor_permit_authentications(1);
863 /* Allow service/style information on the auth context */
864 monitor_permit(mon_dispatch, MONITOR_REQ_AUTHSERV, 1);
865 monitor_permit(mon_dispatch, MONITOR_REQ_AUTH2_READ_BANNER, 1);
869 monitor_permit(mon_dispatch, MONITOR_REQ_PAM_START, 1);
875 int mm_answer_auth2_read_banner(int sock, Buffer *m)
880 banner = auth2_read_banner();
881 buffer_put_cstring(m, banner != NULL ? banner : "");
882 mm_request_send(sock, MONITOR_ANS_AUTH2_READ_BANNER, m);
889 mm_answer_authserv(int sock, Buffer *m)
891 monitor_permit_authentications(1);
893 authctxt->service = buffer_get_string(m, NULL);
894 authctxt->style = buffer_get_string(m, NULL);
895 debug3("%s: service=%s, style=%s",
896 __func__, authctxt->service, authctxt->style);
898 if (strlen(authctxt->style) == 0) {
899 free(authctxt->style);
900 authctxt->style = NULL;
907 mm_answer_authpassword(int sock, Buffer *m)
909 static int call_count;
914 passwd = buffer_get_string(m, &plen);
915 #if !defined(ANDROID)
916 /* Only authenticate if the context is valid */
917 authenticated = options.password_authentication &&
918 auth_password(authctxt, passwd);
920 /* no password authentication in Android. */
923 explicit_bzero(passwd, strlen(passwd));
927 buffer_put_int(m, authenticated);
929 debug3("%s: sending result %d", __func__, authenticated);
930 mm_request_send(sock, MONITOR_ANS_AUTHPASSWORD, m);
933 if (plen == 0 && call_count == 1)
934 auth_method = "none";
936 auth_method = "password";
938 /* Causes monitor loop to terminate if authenticated */
939 return (authenticated);
944 mm_answer_bsdauthquery(int sock, Buffer *m)
946 char *name, *infotxt;
952 success = bsdauth_query(authctxt, &name, &infotxt, &numprompts,
953 &prompts, &echo_on) < 0 ? 0 : 1;
956 buffer_put_int(m, success);
958 buffer_put_cstring(m, prompts[0]);
960 debug3("%s: sending challenge success: %u", __func__, success);
961 mm_request_send(sock, MONITOR_ANS_BSDAUTHQUERY, m);
974 mm_answer_bsdauthrespond(int sock, Buffer *m)
979 if (authctxt->as == 0)
980 fatal("%s: no bsd auth session", __func__);
982 response = buffer_get_string(m, NULL);
983 authok = options.challenge_response_authentication &&
984 auth_userresponse(authctxt->as, response, 0);
986 debug3("%s: <%s> = <%d>", __func__, response, authok);
990 buffer_put_int(m, authok);
992 debug3("%s: sending authenticated: %d", __func__, authok);
993 mm_request_send(sock, MONITOR_ANS_BSDAUTHRESPOND, m);
996 auth_method = "keyboard-interactive";
997 auth_submethod = "bsdauth";
999 auth_method = "bsdauth";
1001 return (authok != 0);
1007 mm_answer_skeyquery(int sock, Buffer *m)
1010 char challenge[1024];
1013 success = _compat_skeychallenge(&skey, authctxt->user, challenge,
1014 sizeof(challenge)) < 0 ? 0 : 1;
1017 buffer_put_int(m, success);
1019 buffer_put_cstring(m, challenge);
1021 debug3("%s: sending challenge success: %u", __func__, success);
1022 mm_request_send(sock, MONITOR_ANS_SKEYQUERY, m);
1028 mm_answer_skeyrespond(int sock, Buffer *m)
1033 response = buffer_get_string(m, NULL);
1035 authok = (options.challenge_response_authentication &&
1037 skey_haskey(authctxt->pw->pw_name) == 0 &&
1038 skey_passcheck(authctxt->pw->pw_name, response) != -1);
1043 buffer_put_int(m, authok);
1045 debug3("%s: sending authenticated: %d", __func__, authok);
1046 mm_request_send(sock, MONITOR_ANS_SKEYRESPOND, m);
1048 auth_method = "skey";
1050 return (authok != 0);
1056 mm_answer_pam_start(int sock, Buffer *m)
1058 if (!options.use_pam)
1059 fatal("UsePAM not set, but ended up in %s anyway", __func__);
1061 start_pam(authctxt);
1063 monitor_permit(mon_dispatch, MONITOR_REQ_PAM_ACCOUNT, 1);
1069 mm_answer_pam_account(int sock, Buffer *m)
1073 if (!options.use_pam)
1074 fatal("UsePAM not set, but ended up in %s anyway", __func__);
1076 ret = do_pam_account();
1078 buffer_put_int(m, ret);
1079 buffer_put_string(m, buffer_ptr(&loginmsg), buffer_len(&loginmsg));
1081 mm_request_send(sock, MONITOR_ANS_PAM_ACCOUNT, m);
1086 static void *sshpam_ctxt, *sshpam_authok;
1087 extern KbdintDevice sshpam_device;
1090 mm_answer_pam_init_ctx(int sock, Buffer *m)
1093 debug3("%s", __func__);
1094 authctxt->user = buffer_get_string(m, NULL);
1095 sshpam_ctxt = (sshpam_device.init_ctx)(authctxt);
1096 sshpam_authok = NULL;
1098 if (sshpam_ctxt != NULL) {
1099 monitor_permit(mon_dispatch, MONITOR_REQ_PAM_FREE_CTX, 1);
1100 buffer_put_int(m, 1);
1102 buffer_put_int(m, 0);
1104 mm_request_send(sock, MONITOR_ANS_PAM_INIT_CTX, m);
1109 mm_answer_pam_query(int sock, Buffer *m)
1111 char *name = NULL, *info = NULL, **prompts = NULL;
1112 u_int i, num = 0, *echo_on = 0;
1115 debug3("%s", __func__);
1116 sshpam_authok = NULL;
1117 ret = (sshpam_device.query)(sshpam_ctxt, &name, &info, &num, &prompts, &echo_on);
1118 if (ret == 0 && num == 0)
1119 sshpam_authok = sshpam_ctxt;
1120 if (num > 1 || name == NULL || info == NULL)
1123 buffer_put_int(m, ret);
1124 buffer_put_cstring(m, name);
1126 buffer_put_cstring(m, info);
1128 buffer_put_int(m, num);
1129 for (i = 0; i < num; ++i) {
1130 buffer_put_cstring(m, prompts[i]);
1132 buffer_put_int(m, echo_on[i]);
1136 auth_method = "keyboard-interactive";
1137 auth_submethod = "pam";
1138 mm_request_send(sock, MONITOR_ANS_PAM_QUERY, m);
1143 mm_answer_pam_respond(int sock, Buffer *m)
1149 debug3("%s", __func__);
1150 sshpam_authok = NULL;
1151 num = buffer_get_int(m);
1153 resp = xcalloc(num, sizeof(char *));
1154 for (i = 0; i < num; ++i)
1155 resp[i] = buffer_get_string(m, NULL);
1156 ret = (sshpam_device.respond)(sshpam_ctxt, num, resp);
1157 for (i = 0; i < num; ++i)
1161 ret = (sshpam_device.respond)(sshpam_ctxt, num, NULL);
1164 buffer_put_int(m, ret);
1165 mm_request_send(sock, MONITOR_ANS_PAM_RESPOND, m);
1166 auth_method = "keyboard-interactive";
1167 auth_submethod = "pam";
1169 sshpam_authok = sshpam_ctxt;
1174 mm_answer_pam_free_ctx(int sock, Buffer *m)
1177 debug3("%s", __func__);
1178 (sshpam_device.free_ctx)(sshpam_ctxt);
1180 mm_request_send(sock, MONITOR_ANS_PAM_FREE_CTX, m);
1181 auth_method = "keyboard-interactive";
1182 auth_submethod = "pam";
1183 return (sshpam_authok == sshpam_ctxt);
1188 mm_answer_keyallowed(int sock, Buffer *m)
1191 char *cuser, *chost;
1194 enum mm_keytype type = 0;
1197 debug3("%s entering", __func__);
1199 type = buffer_get_int(m);
1200 cuser = buffer_get_string(m, NULL);
1201 chost = buffer_get_string(m, NULL);
1202 blob = buffer_get_string(m, &bloblen);
1204 key = key_from_blob(blob, bloblen);
1206 if ((compat20 && type == MM_RSAHOSTKEY) ||
1207 (!compat20 && type != MM_RSAHOSTKEY))
1208 fatal("%s: key type and protocol mismatch", __func__);
1210 debug3("%s: key_from_blob: %p", __func__, key);
1212 if (key != NULL && authctxt->valid) {
1213 /* These should not make it past the privsep child */
1214 if (key_type_plain(key->type) == KEY_RSA &&
1215 (datafellows & SSH_BUG_RSASIGMD5) != 0)
1216 fatal("%s: passed a SSH_BUG_RSASIGMD5 key", __func__);
1220 allowed = options.pubkey_authentication &&
1221 !auth2_userkey_already_used(authctxt, key) &&
1222 match_pattern_list(sshkey_ssh_name(key),
1223 options.pubkey_key_types,
1224 strlen(options.pubkey_key_types), 0) == 1 &&
1225 user_key_allowed(authctxt->pw, key);
1226 pubkey_auth_info(authctxt, key, NULL);
1227 auth_method = "publickey";
1228 if (options.pubkey_authentication && allowed != 1)
1229 auth_clear_options();
1232 allowed = options.hostbased_authentication &&
1233 match_pattern_list(sshkey_ssh_name(key),
1234 options.hostbased_key_types,
1235 strlen(options.hostbased_key_types), 0) == 1 &&
1236 hostbased_key_allowed(authctxt->pw,
1238 pubkey_auth_info(authctxt, key,
1239 "client user \"%.100s\", client host \"%.100s\"",
1241 auth_method = "hostbased";
1245 key->type = KEY_RSA1; /* XXX */
1246 allowed = options.rhosts_rsa_authentication &&
1247 auth_rhosts_rsa_key_allowed(authctxt->pw,
1249 if (options.rhosts_rsa_authentication && allowed != 1)
1250 auth_clear_options();
1251 auth_method = "rsa";
1255 fatal("%s: unknown key type %d", __func__, type);
1262 /* clear temporarily storage (used by verify) */
1263 monitor_reset_key_state();
1266 /* Save temporarily for comparison in verify */
1268 key_bloblen = bloblen;
1269 key_blobtype = type;
1270 hostbased_cuser = cuser;
1271 hostbased_chost = chost;
1273 /* Log failed attempt */
1274 auth_log(authctxt, 0, 0, auth_method, NULL);
1280 debug3("%s: key %p is %s",
1281 __func__, key, allowed ? "allowed" : "not allowed");
1284 buffer_put_int(m, allowed);
1285 buffer_put_int(m, forced_command != NULL);
1287 mm_request_send(sock, MONITOR_ANS_KEYALLOWED, m);
1289 if (type == MM_RSAHOSTKEY)
1290 monitor_permit(mon_dispatch, MONITOR_REQ_RSACHALLENGE, allowed);
1296 monitor_valid_userblob(u_char *data, u_int datalen)
1299 char *p, *userstyle;
1304 buffer_append(&b, data, datalen);
1306 if (datafellows & SSH_OLD_SESSIONID) {
1308 len = buffer_len(&b);
1309 if ((session_id2 == NULL) ||
1310 (len < session_id2_len) ||
1311 (timingsafe_bcmp(p, session_id2, session_id2_len) != 0))
1313 buffer_consume(&b, session_id2_len);
1315 p = buffer_get_string(&b, &len);
1316 if ((session_id2 == NULL) ||
1317 (len != session_id2_len) ||
1318 (timingsafe_bcmp(p, session_id2, session_id2_len) != 0))
1322 if (buffer_get_char(&b) != SSH2_MSG_USERAUTH_REQUEST)
1324 p = buffer_get_cstring(&b, NULL);
1325 xasprintf(&userstyle, "%s%s%s", authctxt->user,
1326 authctxt->style ? ":" : "",
1327 authctxt->style ? authctxt->style : "");
1328 if (strcmp(userstyle, p) != 0) {
1329 logit("wrong user name passed to monitor: expected %s != %.100s",
1335 buffer_skip_string(&b);
1336 if (datafellows & SSH_BUG_PKAUTH) {
1337 if (!buffer_get_char(&b))
1340 p = buffer_get_cstring(&b, NULL);
1341 if (strcmp("publickey", p) != 0)
1344 if (!buffer_get_char(&b))
1346 buffer_skip_string(&b);
1348 buffer_skip_string(&b);
1349 if (buffer_len(&b) != 0)
1356 monitor_valid_hostbasedblob(u_char *data, u_int datalen, char *cuser,
1360 char *p, *userstyle;
1365 buffer_append(&b, data, datalen);
1367 p = buffer_get_string(&b, &len);
1368 if ((session_id2 == NULL) ||
1369 (len != session_id2_len) ||
1370 (timingsafe_bcmp(p, session_id2, session_id2_len) != 0))
1374 if (buffer_get_char(&b) != SSH2_MSG_USERAUTH_REQUEST)
1376 p = buffer_get_cstring(&b, NULL);
1377 xasprintf(&userstyle, "%s%s%s", authctxt->user,
1378 authctxt->style ? ":" : "",
1379 authctxt->style ? authctxt->style : "");
1380 if (strcmp(userstyle, p) != 0) {
1381 logit("wrong user name passed to monitor: expected %s != %.100s",
1387 buffer_skip_string(&b); /* service */
1388 p = buffer_get_cstring(&b, NULL);
1389 if (strcmp(p, "hostbased") != 0)
1392 buffer_skip_string(&b); /* pkalg */
1393 buffer_skip_string(&b); /* pkblob */
1395 /* verify client host, strip trailing dot if necessary */
1396 p = buffer_get_string(&b, NULL);
1397 if (((len = strlen(p)) > 0) && p[len - 1] == '.')
1399 if (strcmp(p, chost) != 0)
1403 /* verify client user */
1404 p = buffer_get_string(&b, NULL);
1405 if (strcmp(p, cuser) != 0)
1409 if (buffer_len(&b) != 0)
1416 mm_answer_keyverify(int sock, Buffer *m)
1419 u_char *signature, *data, *blob;
1420 u_int signaturelen, datalen, bloblen;
1424 blob = buffer_get_string(m, &bloblen);
1425 signature = buffer_get_string(m, &signaturelen);
1426 data = buffer_get_string(m, &datalen);
1428 if (hostbased_cuser == NULL || hostbased_chost == NULL ||
1429 !monitor_allowed_key(blob, bloblen))
1430 fatal("%s: bad key, not previously allowed", __func__);
1432 key = key_from_blob(blob, bloblen);
1434 fatal("%s: bad public key blob", __func__);
1436 switch (key_blobtype) {
1438 valid_data = monitor_valid_userblob(data, datalen);
1441 valid_data = monitor_valid_hostbasedblob(data, datalen,
1442 hostbased_cuser, hostbased_chost);
1449 fatal("%s: bad signature data blob", __func__);
1451 verified = key_verify(key, signature, signaturelen, data, datalen);
1452 debug3("%s: key %p signature %s",
1453 __func__, key, (verified == 1) ? "verified" : "unverified");
1455 /* If auth was successful then record key to ensure it isn't reused */
1457 auth2_record_userkey(authctxt, key);
1465 auth_method = key_blobtype == MM_USERKEY ? "publickey" : "hostbased";
1467 monitor_reset_key_state();
1470 buffer_put_int(m, verified);
1471 mm_request_send(sock, MONITOR_ANS_KEYVERIFY, m);
1473 return (verified == 1);
1477 mm_record_login(Session *s, struct passwd *pw)
1480 struct sockaddr_storage from;
1483 * Get IP address of client. If the connection is not a socket, let
1484 * the address be 0.0.0.0.
1486 memset(&from, 0, sizeof(from));
1487 fromlen = sizeof(from);
1488 if (packet_connection_is_on_socket()) {
1489 if (getpeername(packet_get_connection_in(),
1490 (struct sockaddr *)&from, &fromlen) < 0) {
1491 debug("getpeername: %.100s", strerror(errno));
1495 /* Record that there was a login on that tty from the remote host. */
1496 record_login(s->pid, s->tty, pw->pw_name, pw->pw_uid,
1497 get_remote_name_or_ip(utmp_len, options.use_dns),
1498 (struct sockaddr *)&from, fromlen);
1502 mm_session_close(Session *s)
1504 debug3("%s: session %d pid %ld", __func__, s->self, (long)s->pid);
1505 if (s->ttyfd != -1) {
1506 debug3("%s: tty %s ptyfd %d", __func__, s->tty, s->ptyfd);
1507 session_pty_cleanup2(s);
1509 session_unused(s->self);
1513 mm_answer_pty(int sock, Buffer *m)
1515 extern struct monitor *pmonitor;
1519 debug3("%s entering", __func__);
1525 s->authctxt = authctxt;
1526 s->pw = authctxt->pw;
1527 s->pid = pmonitor->m_pid;
1528 res = pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty));
1531 pty_setowner(authctxt->pw, s->tty);
1533 buffer_put_int(m, 1);
1534 buffer_put_cstring(m, s->tty);
1536 /* We need to trick ttyslot */
1537 if (dup2(s->ttyfd, 0) == -1)
1538 fatal("%s: dup2", __func__);
1540 mm_record_login(s, authctxt->pw);
1542 /* Now we can close the file descriptor again */
1545 /* send messages generated by record_login */
1546 buffer_put_string(m, buffer_ptr(&loginmsg), buffer_len(&loginmsg));
1547 buffer_clear(&loginmsg);
1549 mm_request_send(sock, MONITOR_ANS_PTY, m);
1551 if (mm_send_fd(sock, s->ptyfd) == -1 ||
1552 mm_send_fd(sock, s->ttyfd) == -1)
1553 fatal("%s: send fds failed", __func__);
1555 /* make sure nothing uses fd 0 */
1556 if ((fd0 = open(_PATH_DEVNULL, O_RDONLY)) < 0)
1557 fatal("%s: open(/dev/null): %s", __func__, strerror(errno));
1559 error("%s: fd0 %d != 0", __func__, fd0);
1561 /* slave is not needed */
1563 s->ttyfd = s->ptyfd;
1564 /* no need to dup() because nobody closes ptyfd */
1565 s->ptymaster = s->ptyfd;
1567 debug3("%s: tty %s ptyfd %d", __func__, s->tty, s->ttyfd);
1573 mm_session_close(s);
1574 buffer_put_int(m, 0);
1575 mm_request_send(sock, MONITOR_ANS_PTY, m);
1580 mm_answer_pty_cleanup(int sock, Buffer *m)
1585 debug3("%s entering", __func__);
1587 tty = buffer_get_string(m, NULL);
1588 if ((s = session_by_tty(tty)) != NULL)
1589 mm_session_close(s);
1597 mm_answer_sesskey(int sock, Buffer *m)
1602 /* Turn off permissions */
1603 monitor_permit(mon_dispatch, MONITOR_REQ_SESSKEY, 0);
1605 if ((p = BN_new()) == NULL)
1606 fatal("%s: BN_new", __func__);
1608 buffer_get_bignum2(m, p);
1610 rsafail = ssh1_session_key(p);
1613 buffer_put_int(m, rsafail);
1614 buffer_put_bignum2(m, p);
1618 mm_request_send(sock, MONITOR_ANS_SESSKEY, m);
1620 /* Turn on permissions for sessid passing */
1621 monitor_permit(mon_dispatch, MONITOR_REQ_SESSID, 1);
1627 mm_answer_sessid(int sock, Buffer *m)
1631 debug3("%s entering", __func__);
1633 if (buffer_len(m) != 16)
1634 fatal("%s: bad ssh1 session id", __func__);
1635 for (i = 0; i < 16; i++)
1636 session_id[i] = buffer_get_char(m);
1638 /* Turn on permissions for getpwnam */
1639 monitor_permit(mon_dispatch, MONITOR_REQ_PWNAM, 1);
1645 mm_answer_rsa_keyallowed(int sock, Buffer *m)
1649 u_char *blob = NULL;
1653 debug3("%s entering", __func__);
1655 auth_method = "rsa";
1656 if (options.rsa_authentication && authctxt->valid) {
1657 if ((client_n = BN_new()) == NULL)
1658 fatal("%s: BN_new", __func__);
1659 buffer_get_bignum2(m, client_n);
1660 allowed = auth_rsa_key_allowed(authctxt->pw, client_n, &key);
1661 BN_clear_free(client_n);
1664 buffer_put_int(m, allowed);
1665 buffer_put_int(m, forced_command != NULL);
1667 /* clear temporarily storage (used by generate challenge) */
1668 monitor_reset_key_state();
1670 if (allowed && key != NULL) {
1671 key->type = KEY_RSA; /* cheat for key_to_blob */
1672 if (key_to_blob(key, &blob, &blen) == 0)
1673 fatal("%s: key_to_blob failed", __func__);
1674 buffer_put_string(m, blob, blen);
1676 /* Save temporarily for comparison in verify */
1679 key_blobtype = MM_RSAUSERKEY;
1684 mm_request_send(sock, MONITOR_ANS_RSAKEYALLOWED, m);
1686 monitor_permit(mon_dispatch, MONITOR_REQ_RSACHALLENGE, allowed);
1687 monitor_permit(mon_dispatch, MONITOR_REQ_RSARESPONSE, 0);
1692 mm_answer_rsa_challenge(int sock, Buffer *m)
1698 debug3("%s entering", __func__);
1700 if (!authctxt->valid)
1701 fatal("%s: authctxt not valid", __func__);
1702 blob = buffer_get_string(m, &blen);
1703 if (!monitor_allowed_key(blob, blen))
1704 fatal("%s: bad key, not previously allowed", __func__);
1705 if (key_blobtype != MM_RSAUSERKEY && key_blobtype != MM_RSAHOSTKEY)
1706 fatal("%s: key type mismatch", __func__);
1707 if ((key = key_from_blob(blob, blen)) == NULL)
1708 fatal("%s: received bad key", __func__);
1709 if (key->type != KEY_RSA)
1710 fatal("%s: received bad key type %d", __func__, key->type);
1711 key->type = KEY_RSA1;
1713 BN_clear_free(ssh1_challenge);
1714 ssh1_challenge = auth_rsa_generate_challenge(key);
1717 buffer_put_bignum2(m, ssh1_challenge);
1719 debug3("%s sending reply", __func__);
1720 mm_request_send(sock, MONITOR_ANS_RSACHALLENGE, m);
1722 monitor_permit(mon_dispatch, MONITOR_REQ_RSARESPONSE, 1);
1730 mm_answer_rsa_response(int sock, Buffer *m)
1733 u_char *blob, *response;
1737 debug3("%s entering", __func__);
1739 if (!authctxt->valid)
1740 fatal("%s: authctxt not valid", __func__);
1741 if (ssh1_challenge == NULL)
1742 fatal("%s: no ssh1_challenge", __func__);
1744 blob = buffer_get_string(m, &blen);
1745 if (!monitor_allowed_key(blob, blen))
1746 fatal("%s: bad key, not previously allowed", __func__);
1747 if (key_blobtype != MM_RSAUSERKEY && key_blobtype != MM_RSAHOSTKEY)
1748 fatal("%s: key type mismatch: %d", __func__, key_blobtype);
1749 if ((key = key_from_blob(blob, blen)) == NULL)
1750 fatal("%s: received bad key", __func__);
1751 response = buffer_get_string(m, &len);
1753 fatal("%s: received bad response to challenge", __func__);
1754 success = auth_rsa_verify_response(key, ssh1_challenge, response);
1760 auth_method = key_blobtype == MM_RSAUSERKEY ? "rsa" : "rhosts-rsa";
1763 BN_clear_free(ssh1_challenge);
1764 ssh1_challenge = NULL;
1765 monitor_reset_key_state();
1768 buffer_put_int(m, success);
1769 mm_request_send(sock, MONITOR_ANS_RSARESPONSE, m);
1776 mm_answer_term(int sock, Buffer *req)
1778 extern struct monitor *pmonitor;
1781 debug3("%s: tearing down sessions", __func__);
1783 /* The child is terminating */
1784 session_destroy_all(&mm_session_close);
1787 if (options.use_pam)
1791 while (waitpid(pmonitor->m_pid, &status, 0) == -1)
1795 res = WIFEXITED(status) ? WEXITSTATUS(status) : 1;
1797 /* Terminate process */
1801 #ifdef SSH_AUDIT_EVENTS
1802 /* Report that an audit event occurred */
1804 mm_answer_audit_event(int socket, Buffer *m)
1806 ssh_audit_event_t event;
1808 debug3("%s entering", __func__);
1810 event = buffer_get_int(m);
1812 case SSH_AUTH_FAIL_PUBKEY:
1813 case SSH_AUTH_FAIL_HOSTBASED:
1814 case SSH_AUTH_FAIL_GSSAPI:
1815 case SSH_LOGIN_EXCEED_MAXTRIES:
1816 case SSH_LOGIN_ROOT_DENIED:
1817 case SSH_CONNECTION_CLOSE:
1818 case SSH_INVALID_USER:
1822 fatal("Audit event type %d not permitted", event);
1829 mm_answer_audit_command(int socket, Buffer *m)
1834 debug3("%s entering", __func__);
1835 cmd = buffer_get_string(m, &len);
1836 /* sanity check command, if so how? */
1837 audit_run_command(cmd);
1841 #endif /* SSH_AUDIT_EVENTS */
1844 monitor_apply_keystate(struct monitor *pmonitor)
1846 struct ssh *ssh = active_state; /* XXX */
1850 debug3("%s: packet_set_state", __func__);
1851 if ((r = ssh_packet_set_state(ssh, child_state)) != 0)
1852 fatal("%s: packet_set_state: %s", __func__, ssh_err(r));
1853 sshbuf_free(child_state);
1856 if ((kex = ssh->kex) != 0) {
1857 /* XXX set callbacks */
1859 kex->kex[KEX_DH_GRP1_SHA1] = kexdh_server;
1860 kex->kex[KEX_DH_GRP14_SHA1] = kexdh_server;
1861 kex->kex[KEX_DH_GEX_SHA1] = kexgex_server;
1862 kex->kex[KEX_DH_GEX_SHA256] = kexgex_server;
1863 # ifdef OPENSSL_HAS_ECC
1864 kex->kex[KEX_ECDH_SHA2] = kexecdh_server;
1866 #endif /* WITH_OPENSSL */
1867 kex->kex[KEX_C25519_SHA256] = kexc25519_server;
1868 kex->load_host_public_key=&get_hostkey_public_by_type;
1869 kex->load_host_private_key=&get_hostkey_private_by_type;
1870 kex->host_key_index=&get_hostkey_index;
1871 kex->sign = sshd_hostkey_sign;
1874 /* Update with new address */
1875 if (options.compression) {
1876 ssh_packet_set_compress_hooks(ssh, pmonitor->m_zlib,
1877 (ssh_packet_comp_alloc_func *)mm_zalloc,
1878 (ssh_packet_comp_free_func *)mm_zfree);
1882 /* This function requries careful sanity checking */
1885 mm_get_keystate(struct monitor *pmonitor)
1887 debug3("%s: Waiting for new keys", __func__);
1889 if ((child_state = sshbuf_new()) == NULL)
1890 fatal("%s: sshbuf_new failed", __func__);
1891 mm_request_receive_expect(pmonitor->m_sendfd, MONITOR_REQ_KEYEXPORT,
1893 debug3("%s: GOT new keys", __func__);
1899 #define FD_CLOSEONEXEC(x) do { \
1900 if (fcntl(x, F_SETFD, FD_CLOEXEC) == -1) \
1901 fatal("fcntl(%d, F_SETFD)", x); \
1905 monitor_openfds(struct monitor *mon, int do_logfds)
1909 if (socketpair(AF_UNIX, SOCK_STREAM, 0, pair) == -1)
1910 fatal("%s: socketpair: %s", __func__, strerror(errno));
1911 FD_CLOSEONEXEC(pair[0]);
1912 FD_CLOSEONEXEC(pair[1]);
1913 mon->m_recvfd = pair[0];
1914 mon->m_sendfd = pair[1];
1917 if (pipe(pair) == -1)
1918 fatal("%s: pipe: %s", __func__, strerror(errno));
1919 FD_CLOSEONEXEC(pair[0]);
1920 FD_CLOSEONEXEC(pair[1]);
1921 mon->m_log_recvfd = pair[0];
1922 mon->m_log_sendfd = pair[1];
1924 mon->m_log_recvfd = mon->m_log_sendfd = -1;
1927 #define MM_MEMSIZE 65536
1932 struct ssh *ssh = active_state; /* XXX */
1933 struct monitor *mon;
1935 mon = xcalloc(1, sizeof(*mon));
1937 monitor_openfds(mon, 1);
1939 /* Used to share zlib space across processes */
1940 if (options.compression) {
1941 mon->m_zback = mm_create(NULL, MM_MEMSIZE);
1942 mon->m_zlib = mm_create(mon->m_zback, 20 * MM_MEMSIZE);
1944 /* Compression needs to share state across borders */
1945 ssh_packet_set_compress_hooks(ssh, mon->m_zlib,
1946 (ssh_packet_comp_alloc_func *)mm_zalloc,
1947 (ssh_packet_comp_free_func *)mm_zfree);
1954 monitor_reinit(struct monitor *mon)
1956 monitor_openfds(mon, 0);
1961 mm_answer_gss_setup_ctx(int sock, Buffer *m)
1967 goid.elements = buffer_get_string(m, &len);
1970 major = ssh_gssapi_server_ctx(&gsscontext, &goid);
1972 free(goid.elements);
1975 buffer_put_int(m, major);
1977 mm_request_send(sock, MONITOR_ANS_GSSSETUP, m);
1979 /* Now we have a context, enable the step */
1980 monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 1);
1986 mm_answer_gss_accept_ctx(int sock, Buffer *m)
1989 gss_buffer_desc out = GSS_C_EMPTY_BUFFER;
1990 OM_uint32 major, minor;
1991 OM_uint32 flags = 0; /* GSI needs this */
1994 in.value = buffer_get_string(m, &len);
1996 major = ssh_gssapi_accept_ctx(gsscontext, &in, &out, &flags);
2000 buffer_put_int(m, major);
2001 buffer_put_string(m, out.value, out.length);
2002 buffer_put_int(m, flags);
2003 mm_request_send(sock, MONITOR_ANS_GSSSTEP, m);
2005 gss_release_buffer(&minor, &out);
2007 if (major == GSS_S_COMPLETE) {
2008 monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 0);
2009 monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
2010 monitor_permit(mon_dispatch, MONITOR_REQ_GSSCHECKMIC, 1);
2016 mm_answer_gss_checkmic(int sock, Buffer *m)
2018 gss_buffer_desc gssbuf, mic;
2022 gssbuf.value = buffer_get_string(m, &len);
2023 gssbuf.length = len;
2024 mic.value = buffer_get_string(m, &len);
2027 ret = ssh_gssapi_checkmic(gsscontext, &gssbuf, &mic);
2033 buffer_put_int(m, ret);
2035 mm_request_send(sock, MONITOR_ANS_GSSCHECKMIC, m);
2037 if (!GSS_ERROR(ret))
2038 monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
2044 mm_answer_gss_userok(int sock, Buffer *m)
2048 authenticated = authctxt->valid && ssh_gssapi_userok(authctxt->user);
2051 buffer_put_int(m, authenticated);
2053 debug3("%s: sending result %d", __func__, authenticated);
2054 mm_request_send(sock, MONITOR_ANS_GSSUSEROK, m);
2056 auth_method = "gssapi-with-mic";
2058 /* Monitor loop will terminate if authenticated */
2059 return (authenticated);