Annotation of src/usr.bin/ssh/monitor.c, Revision 1.42
1.1 provos 1: /*
2: * Copyright 2002 Niels Provos <provos@citi.umich.edu>
3: * Copyright 2002 Markus Friedl <markus@openbsd.org>
4: * All rights reserved.
5: *
6: * Redistribution and use in source and binary forms, with or without
7: * modification, are permitted provided that the following conditions
8: * are met:
9: * 1. Redistributions of source code must retain the above copyright
10: * notice, this list of conditions and the following disclaimer.
11: * 2. Redistributions in binary form must reproduce the above copyright
12: * notice, this list of conditions and the following disclaimer in the
13: * documentation and/or other materials provided with the distribution.
14: *
15: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
16: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
17: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
18: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
19: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
20: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
21: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
22: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
23: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
24: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
25: */
26:
27: #include "includes.h"
1.42 ! markus 28: RCSID("$OpenBSD: monitor.c,v 1.41 2003/05/24 09:30:40 djm Exp $");
1.1 provos 29:
30: #include <openssl/dh.h>
31:
32: #ifdef SKEY
33: #include <skey.h>
34: #endif
35:
36: #include "ssh.h"
37: #include "auth.h"
38: #include "kex.h"
39: #include "dh.h"
40: #include "zlib.h"
41: #include "packet.h"
42: #include "auth-options.h"
43: #include "sshpty.h"
44: #include "channels.h"
45: #include "session.h"
46: #include "sshlogin.h"
47: #include "canohost.h"
48: #include "log.h"
49: #include "servconf.h"
50: #include "monitor.h"
51: #include "monitor_mm.h"
52: #include "monitor_wrap.h"
53: #include "monitor_fdpass.h"
54: #include "xmalloc.h"
55: #include "misc.h"
56: #include "buffer.h"
57: #include "bufaux.h"
58: #include "compat.h"
59: #include "ssh2.h"
60: #include "mpaux.h"
61:
62: /* Imports */
63: extern ServerOptions options;
64: extern u_int utmp_len;
65: extern Newkeys *current_keys[];
66: extern z_stream incoming_stream;
67: extern z_stream outgoing_stream;
68: extern u_char session_id[];
69: extern Buffer input, output;
70: extern Buffer auth_debug;
71: extern int auth_debug_init;
72:
73: /* State exported from the child */
74:
75: struct {
76: z_stream incoming;
77: z_stream outgoing;
78: u_char *keyin;
79: u_int keyinlen;
80: u_char *keyout;
81: u_int keyoutlen;
82: u_char *ivin;
83: u_int ivinlen;
84: u_char *ivout;
85: u_int ivoutlen;
1.15 markus 86: u_char *ssh1key;
87: u_int ssh1keylen;
1.1 provos 88: int ssh1cipher;
89: int ssh1protoflags;
90: u_char *input;
91: u_int ilen;
92: u_char *output;
93: u_int olen;
94: } child_state;
95:
96: /* Functions on the montior that answer unprivileged requests */
97:
98: int mm_answer_moduli(int, Buffer *);
99: int mm_answer_sign(int, Buffer *);
100: int mm_answer_pwnamallow(int, Buffer *);
1.10 djm 101: int mm_answer_auth2_read_banner(int, Buffer *);
1.1 provos 102: int mm_answer_authserv(int, Buffer *);
103: int mm_answer_authpassword(int, Buffer *);
104: int mm_answer_bsdauthquery(int, Buffer *);
105: int mm_answer_bsdauthrespond(int, Buffer *);
106: int mm_answer_skeyquery(int, Buffer *);
107: int mm_answer_skeyrespond(int, Buffer *);
108: int mm_answer_keyallowed(int, Buffer *);
109: int mm_answer_keyverify(int, Buffer *);
110: int mm_answer_pty(int, Buffer *);
111: int mm_answer_pty_cleanup(int, Buffer *);
112: int mm_answer_term(int, Buffer *);
113: int mm_answer_rsa_keyallowed(int, Buffer *);
114: int mm_answer_rsa_challenge(int, Buffer *);
115: int mm_answer_rsa_response(int, Buffer *);
116: int mm_answer_sesskey(int, Buffer *);
117: int mm_answer_sessid(int, Buffer *);
118:
1.29 markus 119: #ifdef KRB4
120: int mm_answer_krb4(int, Buffer *);
121: #endif
1.25 itojun 122: #ifdef KRB5
123: int mm_answer_krb5(int, Buffer *);
124: #endif
125:
1.1 provos 126: static Authctxt *authctxt;
127: static BIGNUM *ssh1_challenge = NULL; /* used for ssh1 rsa auth */
128:
129: /* local state for key verify */
130: static u_char *key_blob = NULL;
131: static u_int key_bloblen = 0;
132: static int key_blobtype = MM_NOKEY;
1.26 markus 133: static char *hostbased_cuser = NULL;
134: static char *hostbased_chost = NULL;
1.1 provos 135: static char *auth_method = "unknown";
1.13 markus 136: static int session_id2_len = 0;
137: static u_char *session_id2 = NULL;
1.40 markus 138: static pid_t monitor_child_pid;
1.1 provos 139:
140: struct mon_table {
141: enum monitor_reqtype type;
142: int flags;
143: int (*f)(int, Buffer *);
144: };
145:
146: #define MON_ISAUTH 0x0004 /* Required for Authentication */
147: #define MON_AUTHDECIDE 0x0008 /* Decides Authentication */
148: #define MON_ONCE 0x0010 /* Disable after calling */
149:
150: #define MON_AUTH (MON_ISAUTH|MON_AUTHDECIDE)
151:
152: #define MON_PERMIT 0x1000 /* Request is permitted */
153:
154: struct mon_table mon_dispatch_proto20[] = {
155: {MONITOR_REQ_MODULI, MON_ONCE, mm_answer_moduli},
156: {MONITOR_REQ_SIGN, MON_ONCE, mm_answer_sign},
157: {MONITOR_REQ_PWNAM, MON_ONCE, mm_answer_pwnamallow},
158: {MONITOR_REQ_AUTHSERV, MON_ONCE, mm_answer_authserv},
1.10 djm 159: {MONITOR_REQ_AUTH2_READ_BANNER, MON_ONCE, mm_answer_auth2_read_banner},
1.1 provos 160: {MONITOR_REQ_AUTHPASSWORD, MON_AUTH, mm_answer_authpassword},
161: #ifdef BSD_AUTH
162: {MONITOR_REQ_BSDAUTHQUERY, MON_ISAUTH, mm_answer_bsdauthquery},
163: {MONITOR_REQ_BSDAUTHRESPOND, MON_AUTH,mm_answer_bsdauthrespond},
164: #endif
165: #ifdef SKEY
166: {MONITOR_REQ_SKEYQUERY, MON_ISAUTH, mm_answer_skeyquery},
167: {MONITOR_REQ_SKEYRESPOND, MON_AUTH, mm_answer_skeyrespond},
168: #endif
169: {MONITOR_REQ_KEYALLOWED, MON_ISAUTH, mm_answer_keyallowed},
170: {MONITOR_REQ_KEYVERIFY, MON_AUTH, mm_answer_keyverify},
1.39 markus 171: #ifdef KRB5
172: {MONITOR_REQ_KRB5, MON_ONCE|MON_AUTH, mm_answer_krb5},
173: #endif
1.1 provos 174: {0, 0, NULL}
175: };
176:
177: struct mon_table mon_dispatch_postauth20[] = {
178: {MONITOR_REQ_MODULI, 0, mm_answer_moduli},
179: {MONITOR_REQ_SIGN, 0, mm_answer_sign},
180: {MONITOR_REQ_PTY, 0, mm_answer_pty},
181: {MONITOR_REQ_PTYCLEANUP, 0, mm_answer_pty_cleanup},
182: {MONITOR_REQ_TERM, 0, mm_answer_term},
183: {0, 0, NULL}
184: };
185:
186: struct mon_table mon_dispatch_proto15[] = {
187: {MONITOR_REQ_PWNAM, MON_ONCE, mm_answer_pwnamallow},
188: {MONITOR_REQ_SESSKEY, MON_ONCE, mm_answer_sesskey},
189: {MONITOR_REQ_SESSID, MON_ONCE, mm_answer_sessid},
190: {MONITOR_REQ_AUTHPASSWORD, MON_AUTH, mm_answer_authpassword},
191: {MONITOR_REQ_RSAKEYALLOWED, MON_ISAUTH, mm_answer_rsa_keyallowed},
192: {MONITOR_REQ_KEYALLOWED, MON_ISAUTH, mm_answer_keyallowed},
193: {MONITOR_REQ_RSACHALLENGE, MON_ONCE, mm_answer_rsa_challenge},
194: {MONITOR_REQ_RSARESPONSE, MON_ONCE|MON_AUTHDECIDE, mm_answer_rsa_response},
195: #ifdef BSD_AUTH
196: {MONITOR_REQ_BSDAUTHQUERY, MON_ISAUTH, mm_answer_bsdauthquery},
197: {MONITOR_REQ_BSDAUTHRESPOND, MON_AUTH,mm_answer_bsdauthrespond},
198: #endif
199: #ifdef SKEY
200: {MONITOR_REQ_SKEYQUERY, MON_ISAUTH, mm_answer_skeyquery},
201: {MONITOR_REQ_SKEYRESPOND, MON_AUTH, mm_answer_skeyrespond},
202: #endif
1.29 markus 203: #ifdef KRB4
204: {MONITOR_REQ_KRB4, MON_ONCE|MON_AUTH, mm_answer_krb4},
205: #endif
1.25 itojun 206: #ifdef KRB5
207: {MONITOR_REQ_KRB5, MON_ONCE|MON_AUTH, mm_answer_krb5},
208: #endif
1.1 provos 209: {0, 0, NULL}
210: };
211:
212: struct mon_table mon_dispatch_postauth15[] = {
213: {MONITOR_REQ_PTY, MON_ONCE, mm_answer_pty},
214: {MONITOR_REQ_PTYCLEANUP, MON_ONCE, mm_answer_pty_cleanup},
215: {MONITOR_REQ_TERM, 0, mm_answer_term},
216: {0, 0, NULL}
217: };
218:
219: struct mon_table *mon_dispatch;
220:
221: /* Specifies if a certain message is allowed at the moment */
222:
223: static void
224: monitor_permit(struct mon_table *ent, enum monitor_reqtype type, int permit)
225: {
226: while (ent->f != NULL) {
227: if (ent->type == type) {
228: ent->flags &= ~MON_PERMIT;
229: ent->flags |= permit ? MON_PERMIT : 0;
230: return;
231: }
232: ent++;
233: }
234: }
235:
236: static void
237: monitor_permit_authentications(int permit)
238: {
239: struct mon_table *ent = mon_dispatch;
240:
241: while (ent->f != NULL) {
242: if (ent->flags & MON_AUTH) {
243: ent->flags &= ~MON_PERMIT;
244: ent->flags |= permit ? MON_PERMIT : 0;
245: }
246: ent++;
247: }
248: }
249:
250: Authctxt *
1.11 mouring 251: monitor_child_preauth(struct monitor *pmonitor)
1.1 provos 252: {
253: struct mon_table *ent;
254: int authenticated = 0;
255:
256: debug3("preauth child monitor started");
257:
258: if (compat20) {
259: mon_dispatch = mon_dispatch_proto20;
260:
261: /* Permit requests for moduli and signatures */
262: monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
263: monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
264: } else {
265: mon_dispatch = mon_dispatch_proto15;
266:
267: monitor_permit(mon_dispatch, MONITOR_REQ_SESSKEY, 1);
268: }
269:
270: authctxt = authctxt_new();
271:
272: /* The first few requests do not require asynchronous access */
273: while (!authenticated) {
1.11 mouring 274: authenticated = monitor_read(pmonitor, mon_dispatch, &ent);
1.1 provos 275: if (authenticated) {
276: if (!(ent->flags & MON_AUTHDECIDE))
277: fatal("%s: unexpected authentication from %d",
1.14 markus 278: __func__, ent->type);
1.1 provos 279: if (authctxt->pw->pw_uid == 0 &&
280: !auth_root_allowed(auth_method))
281: authenticated = 0;
282: }
283:
284: if (ent->flags & MON_AUTHDECIDE) {
285: auth_log(authctxt, authenticated, auth_method,
286: compat20 ? " ssh2" : "");
287: if (!authenticated)
288: authctxt->failures++;
289: }
290: }
291:
292: if (!authctxt->valid)
1.14 markus 293: fatal("%s: authenticated invalid user", __func__);
1.1 provos 294:
295: debug("%s: %s has been authenticated by privileged process",
1.14 markus 296: __func__, authctxt->user);
1.1 provos 297:
1.11 mouring 298: mm_get_keystate(pmonitor);
1.1 provos 299:
300: return (authctxt);
301: }
302:
1.40 markus 303: static void
304: monitor_set_child_handler(pid_t pid)
305: {
306: monitor_child_pid = pid;
307: }
308:
309: static void
310: monitor_child_handler(int signal)
311: {
312: kill(monitor_child_pid, signal);
313: }
314:
1.1 provos 315: void
1.11 mouring 316: monitor_child_postauth(struct monitor *pmonitor)
1.1 provos 317: {
1.40 markus 318: monitor_set_child_handler(pmonitor->m_pid);
319: signal(SIGHUP, &monitor_child_handler);
320: signal(SIGTERM, &monitor_child_handler);
321:
1.1 provos 322: if (compat20) {
323: mon_dispatch = mon_dispatch_postauth20;
324:
325: /* Permit requests for moduli and signatures */
326: monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
327: monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
328: monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1);
329:
330: } else {
331: mon_dispatch = mon_dispatch_postauth15;
332: monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1);
333: }
334: if (!no_pty_flag) {
335: monitor_permit(mon_dispatch, MONITOR_REQ_PTY, 1);
336: monitor_permit(mon_dispatch, MONITOR_REQ_PTYCLEANUP, 1);
337: }
338:
339: for (;;)
1.11 mouring 340: monitor_read(pmonitor, mon_dispatch, NULL);
1.1 provos 341: }
342:
343: void
1.11 mouring 344: monitor_sync(struct monitor *pmonitor)
1.1 provos 345: {
1.16 djm 346: if (options.compression) {
347: /* The member allocation is not visible, so sync it */
348: mm_share_sync(&pmonitor->m_zlib, &pmonitor->m_zback);
349: }
1.1 provos 350: }
351:
352: int
1.11 mouring 353: monitor_read(struct monitor *pmonitor, struct mon_table *ent,
1.1 provos 354: struct mon_table **pent)
355: {
356: Buffer m;
357: int ret;
358: u_char type;
359:
360: buffer_init(&m);
361:
1.11 mouring 362: mm_request_receive(pmonitor->m_sendfd, &m);
1.1 provos 363: type = buffer_get_char(&m);
364:
1.14 markus 365: debug3("%s: checking request %d", __func__, type);
1.1 provos 366:
367: while (ent->f != NULL) {
368: if (ent->type == type)
369: break;
370: ent++;
371: }
372:
373: if (ent->f != NULL) {
374: if (!(ent->flags & MON_PERMIT))
1.14 markus 375: fatal("%s: unpermitted request %d", __func__,
1.1 provos 376: type);
1.11 mouring 377: ret = (*ent->f)(pmonitor->m_sendfd, &m);
1.1 provos 378: buffer_free(&m);
379:
380: /* The child may use this request only once, disable it */
381: if (ent->flags & MON_ONCE) {
1.14 markus 382: debug2("%s: %d used once, disabling now", __func__,
1.1 provos 383: type);
384: ent->flags &= ~MON_PERMIT;
385: }
386:
387: if (pent != NULL)
388: *pent = ent;
1.3 markus 389:
1.1 provos 390: return ret;
391: }
392:
1.14 markus 393: fatal("%s: unsupported request: %d", __func__, type);
1.1 provos 394:
395: /* NOTREACHED */
396: return (-1);
397: }
398:
399: /* allowed key state */
400: static int
401: monitor_allowed_key(u_char *blob, u_int bloblen)
402: {
403: /* make sure key is allowed */
404: if (key_blob == NULL || key_bloblen != bloblen ||
405: memcmp(key_blob, blob, key_bloblen))
406: return (0);
407: return (1);
408: }
409:
410: static void
411: monitor_reset_key_state(void)
412: {
413: /* reset state */
414: if (key_blob != NULL)
415: xfree(key_blob);
416: if (hostbased_cuser != NULL)
417: xfree(hostbased_cuser);
418: if (hostbased_chost != NULL)
419: xfree(hostbased_chost);
420: key_blob = NULL;
421: key_bloblen = 0;
422: key_blobtype = MM_NOKEY;
423: hostbased_cuser = NULL;
424: hostbased_chost = NULL;
425: }
426:
427: int
428: mm_answer_moduli(int socket, Buffer *m)
429: {
430: DH *dh;
431: int min, want, max;
432:
433: min = buffer_get_int(m);
434: want = buffer_get_int(m);
435: max = buffer_get_int(m);
436:
437: debug3("%s: got parameters: %d %d %d",
1.14 markus 438: __func__, min, want, max);
1.1 provos 439: /* We need to check here, too, in case the child got corrupted */
440: if (max < min || want < min || max < want)
441: fatal("%s: bad parameters: %d %d %d",
1.14 markus 442: __func__, min, want, max);
1.1 provos 443:
444: buffer_clear(m);
445:
446: dh = choose_dh(min, want, max);
447: if (dh == NULL) {
448: buffer_put_char(m, 0);
449: return (0);
450: } else {
451: /* Send first bignum */
452: buffer_put_char(m, 1);
453: buffer_put_bignum2(m, dh->p);
454: buffer_put_bignum2(m, dh->g);
1.3 markus 455:
1.1 provos 456: DH_free(dh);
457: }
458: mm_request_send(socket, MONITOR_ANS_MODULI, m);
459: return (0);
460: }
461:
462: int
463: mm_answer_sign(int socket, Buffer *m)
464: {
465: Key *key;
466: u_char *p;
467: u_char *signature;
468: u_int siglen, datlen;
469: int keyid;
1.3 markus 470:
1.14 markus 471: debug3("%s", __func__);
1.1 provos 472:
1.3 markus 473: keyid = buffer_get_int(m);
474: p = buffer_get_string(m, &datlen);
1.1 provos 475:
476: if (datlen != 20)
1.19 deraadt 477: fatal("%s: data length incorrect: %u", __func__, datlen);
1.1 provos 478:
1.13 markus 479: /* save session id, it will be passed on the first call */
480: if (session_id2_len == 0) {
481: session_id2_len = datlen;
482: session_id2 = xmalloc(session_id2_len);
483: memcpy(session_id2, p, session_id2_len);
484: }
485:
1.1 provos 486: if ((key = get_hostkey_by_index(keyid)) == NULL)
1.14 markus 487: fatal("%s: no hostkey from index %d", __func__, keyid);
1.1 provos 488: if (key_sign(key, &signature, &siglen, p, datlen) < 0)
1.14 markus 489: fatal("%s: key_sign failed", __func__);
1.1 provos 490:
1.19 deraadt 491: debug3("%s: signature %p(%u)", __func__, signature, siglen);
1.1 provos 492:
493: buffer_clear(m);
494: buffer_put_string(m, signature, siglen);
495:
496: xfree(p);
497: xfree(signature);
498:
499: mm_request_send(socket, MONITOR_ANS_SIGN, m);
500:
501: /* Turn on permissions for getpwnam */
502: monitor_permit(mon_dispatch, MONITOR_REQ_PWNAM, 1);
503:
504: return (0);
505: }
506:
507: /* Retrieves the password entry and also checks if the user is permitted */
508:
509: int
510: mm_answer_pwnamallow(int socket, Buffer *m)
511: {
512: char *login;
513: struct passwd *pwent;
514: int allowed = 0;
1.3 markus 515:
1.14 markus 516: debug3("%s", __func__);
1.1 provos 517:
518: if (authctxt->attempt++ != 0)
1.14 markus 519: fatal("%s: multiple attempts for getpwnam", __func__);
1.1 provos 520:
521: login = buffer_get_string(m, NULL);
522:
523: pwent = getpwnamallow(login);
524:
525: authctxt->user = xstrdup(login);
526: setproctitle("%s [priv]", pwent ? login : "unknown");
527: xfree(login);
528:
529: buffer_clear(m);
530:
531: if (pwent == NULL) {
532: buffer_put_char(m, 0);
533: goto out;
534: }
535:
536: allowed = 1;
1.4 markus 537: authctxt->pw = pwent;
1.1 provos 538: authctxt->valid = 1;
539:
540: buffer_put_char(m, 1);
541: buffer_put_string(m, pwent, sizeof(struct passwd));
542: buffer_put_cstring(m, pwent->pw_name);
543: buffer_put_cstring(m, "*");
544: buffer_put_cstring(m, pwent->pw_gecos);
545: buffer_put_cstring(m, pwent->pw_class);
546: buffer_put_cstring(m, pwent->pw_dir);
547: buffer_put_cstring(m, pwent->pw_shell);
548:
549: out:
1.14 markus 550: debug3("%s: sending MONITOR_ANS_PWNAM: %d", __func__, allowed);
1.1 provos 551: mm_request_send(socket, MONITOR_ANS_PWNAM, m);
552:
553: /* For SSHv1 allow authentication now */
554: if (!compat20)
555: monitor_permit_authentications(1);
1.10 djm 556: else {
1.1 provos 557: /* Allow service/style information on the auth context */
558: monitor_permit(mon_dispatch, MONITOR_REQ_AUTHSERV, 1);
1.10 djm 559: monitor_permit(mon_dispatch, MONITOR_REQ_AUTH2_READ_BANNER, 1);
560: }
561:
562:
563: return (0);
564: }
565:
566: int mm_answer_auth2_read_banner(int socket, Buffer *m)
567: {
568: char *banner;
569:
570: buffer_clear(m);
571: banner = auth2_read_banner();
572: buffer_put_cstring(m, banner != NULL ? banner : "");
573: mm_request_send(socket, MONITOR_ANS_AUTH2_READ_BANNER, m);
1.1 provos 574:
1.10 djm 575: if (banner != NULL)
1.21 deraadt 576: xfree(banner);
1.1 provos 577:
578: return (0);
579: }
580:
581: int
582: mm_answer_authserv(int socket, Buffer *m)
583: {
584: monitor_permit_authentications(1);
585:
586: authctxt->service = buffer_get_string(m, NULL);
587: authctxt->style = buffer_get_string(m, NULL);
1.6 stevesk 588: debug3("%s: service=%s, style=%s",
1.14 markus 589: __func__, authctxt->service, authctxt->style);
1.6 stevesk 590:
1.1 provos 591: if (strlen(authctxt->style) == 0) {
592: xfree(authctxt->style);
593: authctxt->style = NULL;
594: }
595:
596: return (0);
597: }
598:
599: int
600: mm_answer_authpassword(int socket, Buffer *m)
601: {
602: static int call_count;
603: char *passwd;
1.22 stevesk 604: int authenticated;
605: u_int plen;
1.1 provos 606:
607: passwd = buffer_get_string(m, &plen);
608: /* Only authenticate if the context is valid */
1.12 markus 609: authenticated = options.password_authentication &&
610: authctxt->valid && auth_password(authctxt, passwd);
1.1 provos 611: memset(passwd, 0, strlen(passwd));
612: xfree(passwd);
613:
614: buffer_clear(m);
615: buffer_put_int(m, authenticated);
616:
1.14 markus 617: debug3("%s: sending result %d", __func__, authenticated);
1.1 provos 618: mm_request_send(socket, MONITOR_ANS_AUTHPASSWORD, m);
619:
620: call_count++;
621: if (plen == 0 && call_count == 1)
622: auth_method = "none";
623: else
624: auth_method = "password";
625:
626: /* Causes monitor loop to terminate if authenticated */
627: return (authenticated);
628: }
629:
630: #ifdef BSD_AUTH
631: int
632: mm_answer_bsdauthquery(int socket, Buffer *m)
633: {
634: char *name, *infotxt;
635: u_int numprompts;
636: u_int *echo_on;
637: char **prompts;
1.31 markus 638: u_int success;
1.1 provos 639:
1.31 markus 640: success = bsdauth_query(authctxt, &name, &infotxt, &numprompts,
641: &prompts, &echo_on) < 0 ? 0 : 1;
1.1 provos 642:
643: buffer_clear(m);
1.31 markus 644: buffer_put_int(m, success);
645: if (success)
1.1 provos 646: buffer_put_cstring(m, prompts[0]);
647:
1.31 markus 648: debug3("%s: sending challenge success: %u", __func__, success);
1.1 provos 649: mm_request_send(socket, MONITOR_ANS_BSDAUTHQUERY, m);
650:
1.31 markus 651: if (success) {
1.1 provos 652: xfree(name);
653: xfree(infotxt);
654: xfree(prompts);
655: xfree(echo_on);
656: }
657:
658: return (0);
659: }
660:
661: int
662: mm_answer_bsdauthrespond(int socket, Buffer *m)
663: {
664: char *response;
665: int authok;
666:
667: if (authctxt->as == 0)
1.14 markus 668: fatal("%s: no bsd auth session", __func__);
1.1 provos 669:
670: response = buffer_get_string(m, NULL);
1.12 markus 671: authok = options.challenge_response_authentication &&
672: auth_userresponse(authctxt->as, response, 0);
1.1 provos 673: authctxt->as = NULL;
1.14 markus 674: debug3("%s: <%s> = <%d>", __func__, response, authok);
1.1 provos 675: xfree(response);
676:
677: buffer_clear(m);
678: buffer_put_int(m, authok);
679:
1.14 markus 680: debug3("%s: sending authenticated: %d", __func__, authok);
1.1 provos 681: mm_request_send(socket, MONITOR_ANS_BSDAUTHRESPOND, m);
682:
683: auth_method = "bsdauth";
684:
685: return (authok != 0);
686: }
687: #endif
688:
689: #ifdef SKEY
690: int
691: mm_answer_skeyquery(int socket, Buffer *m)
692: {
693: struct skey skey;
694: char challenge[1024];
1.31 markus 695: u_int success;
1.1 provos 696:
1.31 markus 697: success = skeychallenge(&skey, authctxt->user, challenge) < 0 ? 0 : 1;
1.1 provos 698:
699: buffer_clear(m);
1.31 markus 700: buffer_put_int(m, success);
701: if (success)
1.1 provos 702: buffer_put_cstring(m, challenge);
703:
1.31 markus 704: debug3("%s: sending challenge success: %u", __func__, success);
1.1 provos 705: mm_request_send(socket, MONITOR_ANS_SKEYQUERY, m);
706:
707: return (0);
708: }
709:
710: int
711: mm_answer_skeyrespond(int socket, Buffer *m)
712: {
713: char *response;
714: int authok;
715:
716: response = buffer_get_string(m, NULL);
717:
1.12 markus 718: authok = (options.challenge_response_authentication &&
719: authctxt->valid &&
1.1 provos 720: skey_haskey(authctxt->pw->pw_name) == 0 &&
721: skey_passcheck(authctxt->pw->pw_name, response) != -1);
722:
723: xfree(response);
724:
725: buffer_clear(m);
726: buffer_put_int(m, authok);
727:
1.14 markus 728: debug3("%s: sending authenticated: %d", __func__, authok);
1.1 provos 729: mm_request_send(socket, MONITOR_ANS_SKEYRESPOND, m);
730:
731: auth_method = "skey";
732:
733: return (authok != 0);
734: }
735: #endif
736:
1.2 markus 737: static void
1.1 provos 738: mm_append_debug(Buffer *m)
739: {
740: if (auth_debug_init && buffer_len(&auth_debug)) {
1.14 markus 741: debug3("%s: Appending debug messages for child", __func__);
1.1 provos 742: buffer_append(m, buffer_ptr(&auth_debug),
743: buffer_len(&auth_debug));
744: buffer_clear(&auth_debug);
745: }
746: }
747:
748: int
749: mm_answer_keyallowed(int socket, Buffer *m)
750: {
751: Key *key;
1.26 markus 752: char *cuser, *chost;
753: u_char *blob;
1.1 provos 754: u_int bloblen;
755: enum mm_keytype type = 0;
756: int allowed = 0;
757:
1.14 markus 758: debug3("%s entering", __func__);
1.3 markus 759:
1.1 provos 760: type = buffer_get_int(m);
761: cuser = buffer_get_string(m, NULL);
762: chost = buffer_get_string(m, NULL);
763: blob = buffer_get_string(m, &bloblen);
764:
765: key = key_from_blob(blob, bloblen);
766:
767: if ((compat20 && type == MM_RSAHOSTKEY) ||
768: (!compat20 && type != MM_RSAHOSTKEY))
1.14 markus 769: fatal("%s: key type and protocol mismatch", __func__);
1.1 provos 770:
1.14 markus 771: debug3("%s: key_from_blob: %p", __func__, key);
1.1 provos 772:
773: if (key != NULL && authctxt->pw != NULL) {
774: switch(type) {
775: case MM_USERKEY:
1.12 markus 776: allowed = options.pubkey_authentication &&
777: user_key_allowed(authctxt->pw, key);
1.1 provos 778: break;
779: case MM_HOSTKEY:
1.12 markus 780: allowed = options.hostbased_authentication &&
781: hostbased_key_allowed(authctxt->pw,
1.1 provos 782: cuser, chost, key);
783: break;
784: case MM_RSAHOSTKEY:
785: key->type = KEY_RSA1; /* XXX */
1.12 markus 786: allowed = options.rhosts_rsa_authentication &&
787: auth_rhosts_rsa_key_allowed(authctxt->pw,
1.1 provos 788: cuser, chost, key);
789: break;
790: default:
1.14 markus 791: fatal("%s: unknown key type %d", __func__, type);
1.1 provos 792: break;
793: }
1.33 markus 794: }
795: if (key != NULL)
1.1 provos 796: key_free(key);
797:
798: /* clear temporarily storage (used by verify) */
799: monitor_reset_key_state();
800:
801: if (allowed) {
802: /* Save temporarily for comparison in verify */
803: key_blob = blob;
804: key_bloblen = bloblen;
805: key_blobtype = type;
806: hostbased_cuser = cuser;
807: hostbased_chost = chost;
808: }
809:
810: debug3("%s: key %p is %s",
1.14 markus 811: __func__, key, allowed ? "allowed" : "disallowed");
1.1 provos 812:
813: buffer_clear(m);
814: buffer_put_int(m, allowed);
1.32 markus 815: buffer_put_int(m, forced_command != NULL);
1.1 provos 816:
817: mm_append_debug(m);
818:
819: mm_request_send(socket, MONITOR_ANS_KEYALLOWED, m);
820:
821: if (type == MM_RSAHOSTKEY)
822: monitor_permit(mon_dispatch, MONITOR_REQ_RSACHALLENGE, allowed);
823:
824: return (0);
825: }
826:
827: static int
828: monitor_valid_userblob(u_char *data, u_int datalen)
829: {
830: Buffer b;
1.26 markus 831: char *p;
1.1 provos 832: u_int len;
833: int fail = 0;
834:
835: buffer_init(&b);
836: buffer_append(&b, data, datalen);
1.3 markus 837:
1.1 provos 838: if (datafellows & SSH_OLD_SESSIONID) {
1.13 markus 839: p = buffer_ptr(&b);
840: len = buffer_len(&b);
841: if ((session_id2 == NULL) ||
842: (len < session_id2_len) ||
843: (memcmp(p, session_id2, session_id2_len) != 0))
844: fail++;
1.1 provos 845: buffer_consume(&b, session_id2_len);
846: } else {
1.13 markus 847: p = buffer_get_string(&b, &len);
848: if ((session_id2 == NULL) ||
849: (len != session_id2_len) ||
850: (memcmp(p, session_id2, session_id2_len) != 0))
1.1 provos 851: fail++;
1.13 markus 852: xfree(p);
1.1 provos 853: }
854: if (buffer_get_char(&b) != SSH2_MSG_USERAUTH_REQUEST)
855: fail++;
856: p = buffer_get_string(&b, NULL);
857: if (strcmp(authctxt->user, p) != 0) {
1.38 itojun 858: logit("wrong user name passed to monitor: expected %s != %.100s",
1.1 provos 859: authctxt->user, p);
860: fail++;
861: }
862: xfree(p);
863: buffer_skip_string(&b);
864: if (datafellows & SSH_BUG_PKAUTH) {
865: if (!buffer_get_char(&b))
866: fail++;
867: } else {
868: p = buffer_get_string(&b, NULL);
869: if (strcmp("publickey", p) != 0)
870: fail++;
871: xfree(p);
872: if (!buffer_get_char(&b))
873: fail++;
874: buffer_skip_string(&b);
875: }
876: buffer_skip_string(&b);
877: if (buffer_len(&b) != 0)
878: fail++;
879: buffer_free(&b);
880: return (fail == 0);
881: }
882:
883: static int
1.26 markus 884: monitor_valid_hostbasedblob(u_char *data, u_int datalen, char *cuser,
885: char *chost)
1.1 provos 886: {
887: Buffer b;
1.26 markus 888: char *p;
1.1 provos 889: u_int len;
890: int fail = 0;
891:
892: buffer_init(&b);
893: buffer_append(&b, data, datalen);
1.3 markus 894:
1.13 markus 895: p = buffer_get_string(&b, &len);
896: if ((session_id2 == NULL) ||
897: (len != session_id2_len) ||
898: (memcmp(p, session_id2, session_id2_len) != 0))
1.1 provos 899: fail++;
1.13 markus 900: xfree(p);
901:
1.1 provos 902: if (buffer_get_char(&b) != SSH2_MSG_USERAUTH_REQUEST)
903: fail++;
904: p = buffer_get_string(&b, NULL);
905: if (strcmp(authctxt->user, p) != 0) {
1.38 itojun 906: logit("wrong user name passed to monitor: expected %s != %.100s",
1.1 provos 907: authctxt->user, p);
908: fail++;
909: }
910: xfree(p);
911: buffer_skip_string(&b); /* service */
912: p = buffer_get_string(&b, NULL);
913: if (strcmp(p, "hostbased") != 0)
914: fail++;
915: xfree(p);
916: buffer_skip_string(&b); /* pkalg */
917: buffer_skip_string(&b); /* pkblob */
918:
919: /* verify client host, strip trailing dot if necessary */
920: p = buffer_get_string(&b, NULL);
921: if (((len = strlen(p)) > 0) && p[len - 1] == '.')
922: p[len - 1] = '\0';
923: if (strcmp(p, chost) != 0)
924: fail++;
925: xfree(p);
926:
927: /* verify client user */
928: p = buffer_get_string(&b, NULL);
929: if (strcmp(p, cuser) != 0)
930: fail++;
931: xfree(p);
932:
933: if (buffer_len(&b) != 0)
934: fail++;
935: buffer_free(&b);
936: return (fail == 0);
937: }
938:
939: int
940: mm_answer_keyverify(int socket, Buffer *m)
941: {
942: Key *key;
943: u_char *signature, *data, *blob;
944: u_int signaturelen, datalen, bloblen;
945: int verified = 0;
946: int valid_data = 0;
947:
948: blob = buffer_get_string(m, &bloblen);
949: signature = buffer_get_string(m, &signaturelen);
950: data = buffer_get_string(m, &datalen);
951:
952: if (hostbased_cuser == NULL || hostbased_chost == NULL ||
1.8 mouring 953: !monitor_allowed_key(blob, bloblen))
1.14 markus 954: fatal("%s: bad key, not previously allowed", __func__);
1.1 provos 955:
956: key = key_from_blob(blob, bloblen);
957: if (key == NULL)
1.14 markus 958: fatal("%s: bad public key blob", __func__);
1.1 provos 959:
960: switch (key_blobtype) {
961: case MM_USERKEY:
962: valid_data = monitor_valid_userblob(data, datalen);
963: break;
964: case MM_HOSTKEY:
965: valid_data = monitor_valid_hostbasedblob(data, datalen,
966: hostbased_cuser, hostbased_chost);
967: break;
968: default:
969: valid_data = 0;
970: break;
971: }
972: if (!valid_data)
1.14 markus 973: fatal("%s: bad signature data blob", __func__);
1.1 provos 974:
975: verified = key_verify(key, signature, signaturelen, data, datalen);
976: debug3("%s: key %p signature %s",
1.14 markus 977: __func__, key, verified ? "verified" : "unverified");
1.1 provos 978:
979: key_free(key);
980: xfree(blob);
981: xfree(signature);
982: xfree(data);
983:
1.17 stevesk 984: auth_method = key_blobtype == MM_USERKEY ? "publickey" : "hostbased";
985:
1.1 provos 986: monitor_reset_key_state();
1.3 markus 987:
1.1 provos 988: buffer_clear(m);
989: buffer_put_int(m, verified);
990: mm_request_send(socket, MONITOR_ANS_KEYVERIFY, m);
991:
992: return (verified);
993: }
994:
1.2 markus 995: static void
1.1 provos 996: mm_record_login(Session *s, struct passwd *pw)
997: {
998: socklen_t fromlen;
999: struct sockaddr_storage from;
1000:
1001: /*
1002: * Get IP address of client. If the connection is not a socket, let
1003: * the address be 0.0.0.0.
1004: */
1005: memset(&from, 0, sizeof(from));
1.24 stevesk 1006: fromlen = sizeof(from);
1.1 provos 1007: if (packet_connection_is_on_socket()) {
1008: if (getpeername(packet_get_connection_in(),
1009: (struct sockaddr *) & from, &fromlen) < 0) {
1010: debug("getpeername: %.100s", strerror(errno));
1011: fatal_cleanup();
1012: }
1013: }
1014: /* Record that there was a login on that tty from the remote host. */
1015: record_login(s->pid, s->tty, pw->pw_name, pw->pw_uid,
1.42 ! markus 1016: get_remote_name_or_ip(utmp_len, options.use_dns),
1.24 stevesk 1017: (struct sockaddr *)&from, fromlen);
1.1 provos 1018: }
1019:
1020: static void
1021: mm_session_close(Session *s)
1022: {
1.41 djm 1023: debug3("%s: session %d pid %ld", __func__, s->self, (long)s->pid);
1.1 provos 1024: if (s->ttyfd != -1) {
1.14 markus 1025: debug3("%s: tty %s ptyfd %d", __func__, s->tty, s->ptyfd);
1.1 provos 1026: fatal_remove_cleanup(session_pty_cleanup2, (void *)s);
1027: session_pty_cleanup2(s);
1028: }
1029: s->used = 0;
1030: }
1031:
1032: int
1033: mm_answer_pty(int socket, Buffer *m)
1034: {
1.11 mouring 1035: extern struct monitor *pmonitor;
1.1 provos 1036: Session *s;
1037: int res, fd0;
1038:
1.14 markus 1039: debug3("%s entering", __func__);
1.1 provos 1040:
1041: buffer_clear(m);
1042: s = session_new();
1043: if (s == NULL)
1044: goto error;
1045: s->authctxt = authctxt;
1046: s->pw = authctxt->pw;
1.11 mouring 1047: s->pid = pmonitor->m_pid;
1.1 provos 1048: res = pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty));
1049: if (res == 0)
1050: goto error;
1051: fatal_add_cleanup(session_pty_cleanup2, (void *)s);
1052: pty_setowner(authctxt->pw, s->tty);
1053:
1054: buffer_put_int(m, 1);
1055: buffer_put_cstring(m, s->tty);
1056: mm_request_send(socket, MONITOR_ANS_PTY, m);
1057:
1058: mm_send_fd(socket, s->ptyfd);
1059: mm_send_fd(socket, s->ttyfd);
1060:
1061: /* We need to trick ttyslot */
1062: if (dup2(s->ttyfd, 0) == -1)
1.14 markus 1063: fatal("%s: dup2", __func__);
1.1 provos 1064:
1065: mm_record_login(s, authctxt->pw);
1066:
1067: /* Now we can close the file descriptor again */
1068: close(0);
1069:
1070: /* make sure nothing uses fd 0 */
1071: if ((fd0 = open(_PATH_DEVNULL, O_RDONLY)) < 0)
1.14 markus 1072: fatal("%s: open(/dev/null): %s", __func__, strerror(errno));
1.1 provos 1073: if (fd0 != 0)
1.14 markus 1074: error("%s: fd0 %d != 0", __func__, fd0);
1.1 provos 1075:
1076: /* slave is not needed */
1077: close(s->ttyfd);
1078: s->ttyfd = s->ptyfd;
1079: /* no need to dup() because nobody closes ptyfd */
1080: s->ptymaster = s->ptyfd;
1081:
1.14 markus 1082: debug3("%s: tty %s ptyfd %d", __func__, s->tty, s->ttyfd);
1.1 provos 1083:
1084: return (0);
1085:
1086: error:
1087: if (s != NULL)
1088: mm_session_close(s);
1089: buffer_put_int(m, 0);
1090: mm_request_send(socket, MONITOR_ANS_PTY, m);
1091: return (0);
1092: }
1093:
1094: int
1095: mm_answer_pty_cleanup(int socket, Buffer *m)
1096: {
1097: Session *s;
1098: char *tty;
1099:
1.14 markus 1100: debug3("%s entering", __func__);
1.1 provos 1101:
1102: tty = buffer_get_string(m, NULL);
1103: if ((s = session_by_tty(tty)) != NULL)
1104: mm_session_close(s);
1105: buffer_clear(m);
1106: xfree(tty);
1107: return (0);
1108: }
1109:
1110: int
1111: mm_answer_sesskey(int socket, Buffer *m)
1112: {
1113: BIGNUM *p;
1114: int rsafail;
1115:
1116: /* Turn off permissions */
1117: monitor_permit(mon_dispatch, MONITOR_REQ_SESSKEY, 1);
1118:
1119: if ((p = BN_new()) == NULL)
1.14 markus 1120: fatal("%s: BN_new", __func__);
1.1 provos 1121:
1122: buffer_get_bignum2(m, p);
1123:
1124: rsafail = ssh1_session_key(p);
1125:
1126: buffer_clear(m);
1127: buffer_put_int(m, rsafail);
1128: buffer_put_bignum2(m, p);
1129:
1130: BN_clear_free(p);
1131:
1132: mm_request_send(socket, MONITOR_ANS_SESSKEY, m);
1133:
1134: /* Turn on permissions for sessid passing */
1135: monitor_permit(mon_dispatch, MONITOR_REQ_SESSID, 1);
1136:
1137: return (0);
1138: }
1139:
1140: int
1141: mm_answer_sessid(int socket, Buffer *m)
1142: {
1143: int i;
1144:
1.14 markus 1145: debug3("%s entering", __func__);
1.1 provos 1146:
1147: if (buffer_len(m) != 16)
1.14 markus 1148: fatal("%s: bad ssh1 session id", __func__);
1.1 provos 1149: for (i = 0; i < 16; i++)
1150: session_id[i] = buffer_get_char(m);
1151:
1152: /* Turn on permissions for getpwnam */
1153: monitor_permit(mon_dispatch, MONITOR_REQ_PWNAM, 1);
1154:
1155: return (0);
1156: }
1157:
1158: int
1159: mm_answer_rsa_keyallowed(int socket, Buffer *m)
1160: {
1161: BIGNUM *client_n;
1162: Key *key = NULL;
1.3 markus 1163: u_char *blob = NULL;
1164: u_int blen = 0;
1.1 provos 1165: int allowed = 0;
1166:
1.14 markus 1167: debug3("%s entering", __func__);
1.1 provos 1168:
1.12 markus 1169: if (options.rsa_authentication && authctxt->valid) {
1.1 provos 1170: if ((client_n = BN_new()) == NULL)
1.14 markus 1171: fatal("%s: BN_new", __func__);
1.1 provos 1172: buffer_get_bignum2(m, client_n);
1173: allowed = auth_rsa_key_allowed(authctxt->pw, client_n, &key);
1174: BN_clear_free(client_n);
1175: }
1176: buffer_clear(m);
1177: buffer_put_int(m, allowed);
1.32 markus 1178: buffer_put_int(m, forced_command != NULL);
1.1 provos 1179:
1180: /* clear temporarily storage (used by generate challenge) */
1181: monitor_reset_key_state();
1182:
1183: if (allowed && key != NULL) {
1184: key->type = KEY_RSA; /* cheat for key_to_blob */
1185: if (key_to_blob(key, &blob, &blen) == 0)
1.14 markus 1186: fatal("%s: key_to_blob failed", __func__);
1.1 provos 1187: buffer_put_string(m, blob, blen);
1188:
1189: /* Save temporarily for comparison in verify */
1190: key_blob = blob;
1191: key_bloblen = blen;
1192: key_blobtype = MM_RSAUSERKEY;
1.33 markus 1193: }
1194: if (key != NULL)
1.1 provos 1195: key_free(key);
1196:
1197: mm_append_debug(m);
1198:
1199: mm_request_send(socket, MONITOR_ANS_RSAKEYALLOWED, m);
1200:
1201: monitor_permit(mon_dispatch, MONITOR_REQ_RSACHALLENGE, allowed);
1202: monitor_permit(mon_dispatch, MONITOR_REQ_RSARESPONSE, 0);
1203: return (0);
1204: }
1205:
1206: int
1207: mm_answer_rsa_challenge(int socket, Buffer *m)
1208: {
1209: Key *key = NULL;
1.3 markus 1210: u_char *blob;
1211: u_int blen;
1.1 provos 1212:
1.14 markus 1213: debug3("%s entering", __func__);
1.1 provos 1214:
1215: if (!authctxt->valid)
1.14 markus 1216: fatal("%s: authctxt not valid", __func__);
1.1 provos 1217: blob = buffer_get_string(m, &blen);
1218: if (!monitor_allowed_key(blob, blen))
1.14 markus 1219: fatal("%s: bad key, not previously allowed", __func__);
1.1 provos 1220: if (key_blobtype != MM_RSAUSERKEY && key_blobtype != MM_RSAHOSTKEY)
1.14 markus 1221: fatal("%s: key type mismatch", __func__);
1.1 provos 1222: if ((key = key_from_blob(blob, blen)) == NULL)
1.14 markus 1223: fatal("%s: received bad key", __func__);
1.1 provos 1224:
1225: if (ssh1_challenge)
1226: BN_clear_free(ssh1_challenge);
1227: ssh1_challenge = auth_rsa_generate_challenge(key);
1228:
1229: buffer_clear(m);
1230: buffer_put_bignum2(m, ssh1_challenge);
1231:
1.14 markus 1232: debug3("%s sending reply", __func__);
1.1 provos 1233: mm_request_send(socket, MONITOR_ANS_RSACHALLENGE, m);
1234:
1235: monitor_permit(mon_dispatch, MONITOR_REQ_RSARESPONSE, 1);
1.33 markus 1236:
1237: xfree(blob);
1238: key_free(key);
1.1 provos 1239: return (0);
1240: }
1241:
1242: int
1243: mm_answer_rsa_response(int socket, Buffer *m)
1244: {
1245: Key *key = NULL;
1.3 markus 1246: u_char *blob, *response;
1247: u_int blen, len;
1248: int success;
1.1 provos 1249:
1.14 markus 1250: debug3("%s entering", __func__);
1.1 provos 1251:
1252: if (!authctxt->valid)
1.14 markus 1253: fatal("%s: authctxt not valid", __func__);
1.1 provos 1254: if (ssh1_challenge == NULL)
1.14 markus 1255: fatal("%s: no ssh1_challenge", __func__);
1.1 provos 1256:
1257: blob = buffer_get_string(m, &blen);
1258: if (!monitor_allowed_key(blob, blen))
1.14 markus 1259: fatal("%s: bad key, not previously allowed", __func__);
1.1 provos 1260: if (key_blobtype != MM_RSAUSERKEY && key_blobtype != MM_RSAHOSTKEY)
1.14 markus 1261: fatal("%s: key type mismatch: %d", __func__, key_blobtype);
1.1 provos 1262: if ((key = key_from_blob(blob, blen)) == NULL)
1.14 markus 1263: fatal("%s: received bad key", __func__);
1.1 provos 1264: response = buffer_get_string(m, &len);
1265: if (len != 16)
1.14 markus 1266: fatal("%s: received bad response to challenge", __func__);
1.1 provos 1267: success = auth_rsa_verify_response(key, ssh1_challenge, response);
1268:
1.33 markus 1269: xfree(blob);
1.1 provos 1270: key_free(key);
1271: xfree(response);
1272:
1273: auth_method = key_blobtype == MM_RSAUSERKEY ? "rsa" : "rhosts-rsa";
1274:
1275: /* reset state */
1276: BN_clear_free(ssh1_challenge);
1277: ssh1_challenge = NULL;
1278: monitor_reset_key_state();
1279:
1280: buffer_clear(m);
1281: buffer_put_int(m, success);
1282: mm_request_send(socket, MONITOR_ANS_RSARESPONSE, m);
1283:
1284: return (success);
1285: }
1.25 itojun 1286:
1.29 markus 1287: #ifdef KRB4
1288: int
1289: mm_answer_krb4(int socket, Buffer *m)
1290: {
1291: KTEXT_ST auth, reply;
1292: char *client, *p;
1293: int success;
1294: u_int alen;
1295:
1296: reply.length = auth.length = 0;
1297:
1298: p = buffer_get_string(m, &alen);
1299: if (alen >= MAX_KTXT_LEN)
1300: fatal("%s: auth too large", __func__);
1301: memcpy(auth.dat, p, alen);
1302: auth.length = alen;
1303: memset(p, 0, alen);
1304: xfree(p);
1305:
1306: success = options.kerberos_authentication &&
1307: authctxt->valid &&
1308: auth_krb4(authctxt, &auth, &client, &reply);
1309:
1310: memset(auth.dat, 0, alen);
1311: buffer_clear(m);
1312: buffer_put_int(m, success);
1313:
1314: if (success) {
1315: buffer_put_cstring(m, client);
1316: buffer_put_string(m, reply.dat, reply.length);
1317: if (client)
1318: xfree(client);
1319: if (reply.length)
1320: memset(reply.dat, 0, reply.length);
1321: }
1322:
1323: debug3("%s: sending result %d", __func__, success);
1324: mm_request_send(socket, MONITOR_ANS_KRB4, m);
1325:
1326: auth_method = "kerberos";
1327:
1328: /* Causes monitor loop to terminate if authenticated */
1329: return (success);
1330: }
1331: #endif
1.25 itojun 1332:
1333: #ifdef KRB5
1334: int
1335: mm_answer_krb5(int socket, Buffer *m)
1336: {
1337: krb5_data tkt, reply;
1338: char *client_user;
1339: u_int len;
1340: int success;
1341:
1342: /* use temporary var to avoid size issues on 64bit arch */
1343: tkt.data = buffer_get_string(m, &len);
1344: tkt.length = len;
1345:
1.28 markus 1346: success = options.kerberos_authentication &&
1347: authctxt->valid &&
1.27 markus 1348: auth_krb5(authctxt, &tkt, &client_user, &reply);
1.25 itojun 1349:
1350: if (tkt.length)
1351: xfree(tkt.data);
1352:
1353: buffer_clear(m);
1354: buffer_put_int(m, success);
1355:
1356: if (success) {
1357: buffer_put_cstring(m, client_user);
1358: buffer_put_string(m, reply.data, reply.length);
1359: if (client_user)
1360: xfree(client_user);
1361: if (reply.length)
1362: xfree(reply.data);
1363: }
1364: mm_request_send(socket, MONITOR_ANS_KRB5, m);
1.39 markus 1365:
1366: auth_method = "kerberos";
1.25 itojun 1367:
1368: return success;
1369: }
1370: #endif
1.1 provos 1371:
1372: int
1373: mm_answer_term(int socket, Buffer *req)
1374: {
1.11 mouring 1375: extern struct monitor *pmonitor;
1.1 provos 1376: int res, status;
1377:
1.14 markus 1378: debug3("%s: tearing down sessions", __func__);
1.1 provos 1379:
1380: /* The child is terminating */
1381: session_destroy_all(&mm_session_close);
1382:
1.11 mouring 1383: while (waitpid(pmonitor->m_pid, &status, 0) == -1)
1.9 markus 1384: if (errno != EINTR)
1385: exit(1);
1.1 provos 1386:
1387: res = WIFEXITED(status) ? WEXITSTATUS(status) : 1;
1388:
1389: /* Terminate process */
1390: exit (res);
1391: }
1392:
1393: void
1.11 mouring 1394: monitor_apply_keystate(struct monitor *pmonitor)
1.1 provos 1395: {
1396: if (compat20) {
1397: set_newkeys(MODE_IN);
1398: set_newkeys(MODE_OUT);
1399: } else {
1400: packet_set_protocol_flags(child_state.ssh1protoflags);
1.15 markus 1401: packet_set_encryption_key(child_state.ssh1key,
1402: child_state.ssh1keylen, child_state.ssh1cipher);
1403: xfree(child_state.ssh1key);
1.1 provos 1404: }
1405:
1.15 markus 1406: /* for rc4 and other stateful ciphers */
1.1 provos 1407: packet_set_keycontext(MODE_OUT, child_state.keyout);
1408: xfree(child_state.keyout);
1409: packet_set_keycontext(MODE_IN, child_state.keyin);
1410: xfree(child_state.keyin);
1411:
1412: if (!compat20) {
1413: packet_set_iv(MODE_OUT, child_state.ivout);
1414: xfree(child_state.ivout);
1415: packet_set_iv(MODE_IN, child_state.ivin);
1416: xfree(child_state.ivin);
1417: }
1418:
1419: memcpy(&incoming_stream, &child_state.incoming,
1420: sizeof(incoming_stream));
1421: memcpy(&outgoing_stream, &child_state.outgoing,
1422: sizeof(outgoing_stream));
1.3 markus 1423:
1.1 provos 1424: /* Update with new address */
1.16 djm 1425: if (options.compression)
1426: mm_init_compression(pmonitor->m_zlib);
1.1 provos 1427:
1428: /* Network I/O buffers */
1429: /* XXX inefficient for large buffers, need: buffer_init_from_string */
1430: buffer_clear(&input);
1431: buffer_append(&input, child_state.input, child_state.ilen);
1432: memset(child_state.input, 0, child_state.ilen);
1433: xfree(child_state.input);
1434:
1435: buffer_clear(&output);
1436: buffer_append(&output, child_state.output, child_state.olen);
1437: memset(child_state.output, 0, child_state.olen);
1438: xfree(child_state.output);
1439: }
1440:
1.2 markus 1441: static Kex *
1.1 provos 1442: mm_get_kex(Buffer *m)
1443: {
1444: Kex *kex;
1445: void *blob;
1446: u_int bloblen;
1447:
1448: kex = xmalloc(sizeof(*kex));
1449: memset(kex, 0, sizeof(*kex));
1450: kex->session_id = buffer_get_string(m, &kex->session_id_len);
1.13 markus 1451: if ((session_id2 == NULL) ||
1452: (kex->session_id_len != session_id2_len) ||
1453: (memcmp(kex->session_id, session_id2, session_id2_len) != 0))
1454: fatal("mm_get_get: internal error: bad session id");
1.1 provos 1455: kex->we_need = buffer_get_int(m);
1.34 markus 1456: kex->kex[KEX_DH_GRP1_SHA1] = kexdh_server;
1457: kex->kex[KEX_DH_GEX_SHA1] = kexgex_server;
1.1 provos 1458: kex->server = 1;
1459: kex->hostkey_type = buffer_get_int(m);
1460: kex->kex_type = buffer_get_int(m);
1461: blob = buffer_get_string(m, &bloblen);
1462: buffer_init(&kex->my);
1463: buffer_append(&kex->my, blob, bloblen);
1464: xfree(blob);
1465: blob = buffer_get_string(m, &bloblen);
1466: buffer_init(&kex->peer);
1467: buffer_append(&kex->peer, blob, bloblen);
1468: xfree(blob);
1469: kex->done = 1;
1470: kex->flags = buffer_get_int(m);
1471: kex->client_version_string = buffer_get_string(m, NULL);
1472: kex->server_version_string = buffer_get_string(m, NULL);
1473: kex->load_host_key=&get_hostkey_by_type;
1474: kex->host_key_index=&get_hostkey_index;
1475:
1476: return (kex);
1477: }
1478:
1479: /* This function requries careful sanity checking */
1480:
1481: void
1.11 mouring 1482: mm_get_keystate(struct monitor *pmonitor)
1.1 provos 1483: {
1484: Buffer m;
1485: u_char *blob, *p;
1486: u_int bloblen, plen;
1.37 markus 1487: u_int32_t seqnr, packets;
1488: u_int64_t blocks;
1.1 provos 1489:
1.14 markus 1490: debug3("%s: Waiting for new keys", __func__);
1.1 provos 1491:
1492: buffer_init(&m);
1.11 mouring 1493: mm_request_receive_expect(pmonitor->m_sendfd, MONITOR_REQ_KEYEXPORT, &m);
1.1 provos 1494: if (!compat20) {
1495: child_state.ssh1protoflags = buffer_get_int(&m);
1496: child_state.ssh1cipher = buffer_get_int(&m);
1.15 markus 1497: child_state.ssh1key = buffer_get_string(&m,
1498: &child_state.ssh1keylen);
1.1 provos 1499: child_state.ivout = buffer_get_string(&m,
1500: &child_state.ivoutlen);
1501: child_state.ivin = buffer_get_string(&m, &child_state.ivinlen);
1502: goto skip;
1503: } else {
1504: /* Get the Kex for rekeying */
1.11 mouring 1505: *pmonitor->m_pkex = mm_get_kex(&m);
1.1 provos 1506: }
1507:
1508: blob = buffer_get_string(&m, &bloblen);
1509: current_keys[MODE_OUT] = mm_newkeys_from_blob(blob, bloblen);
1510: xfree(blob);
1511:
1.14 markus 1512: debug3("%s: Waiting for second key", __func__);
1.1 provos 1513: blob = buffer_get_string(&m, &bloblen);
1514: current_keys[MODE_IN] = mm_newkeys_from_blob(blob, bloblen);
1515: xfree(blob);
1.3 markus 1516:
1.1 provos 1517: /* Now get sequence numbers for the packets */
1.37 markus 1518: seqnr = buffer_get_int(&m);
1519: blocks = buffer_get_int64(&m);
1520: packets = buffer_get_int(&m);
1521: packet_set_state(MODE_OUT, seqnr, blocks, packets);
1522: seqnr = buffer_get_int(&m);
1523: blocks = buffer_get_int64(&m);
1524: packets = buffer_get_int(&m);
1525: packet_set_state(MODE_IN, seqnr, blocks, packets);
1.1 provos 1526:
1527: skip:
1528: /* Get the key context */
1529: child_state.keyout = buffer_get_string(&m, &child_state.keyoutlen);
1530: child_state.keyin = buffer_get_string(&m, &child_state.keyinlen);
1531:
1.14 markus 1532: debug3("%s: Getting compression state", __func__);
1.1 provos 1533: /* Get compression state */
1534: p = buffer_get_string(&m, &plen);
1535: if (plen != sizeof(child_state.outgoing))
1.14 markus 1536: fatal("%s: bad request size", __func__);
1.1 provos 1537: memcpy(&child_state.outgoing, p, sizeof(child_state.outgoing));
1538: xfree(p);
1539:
1540: p = buffer_get_string(&m, &plen);
1541: if (plen != sizeof(child_state.incoming))
1.14 markus 1542: fatal("%s: bad request size", __func__);
1.1 provos 1543: memcpy(&child_state.incoming, p, sizeof(child_state.incoming));
1544: xfree(p);
1545:
1546: /* Network I/O buffers */
1.14 markus 1547: debug3("%s: Getting Network I/O buffers", __func__);
1.1 provos 1548: child_state.input = buffer_get_string(&m, &child_state.ilen);
1549: child_state.output = buffer_get_string(&m, &child_state.olen);
1550:
1551: buffer_free(&m);
1552: }
1553:
1554:
1555: /* Allocation functions for zlib */
1556: void *
1557: mm_zalloc(struct mm_master *mm, u_int ncount, u_int size)
1558: {
1.30 markus 1559: size_t len = (size_t) size * ncount;
1.1 provos 1560: void *address;
1561:
1.23 millert 1562: if (len == 0 || ncount > SIZE_T_MAX / size)
1.18 deraadt 1563: fatal("%s: mm_zalloc(%u, %u)", __func__, ncount, size);
1564:
1565: address = mm_malloc(mm, len);
1.1 provos 1566:
1567: return (address);
1568: }
1569:
1570: void
1571: mm_zfree(struct mm_master *mm, void *address)
1572: {
1573: mm_free(mm, address);
1574: }
1575:
1576: void
1577: mm_init_compression(struct mm_master *mm)
1578: {
1579: outgoing_stream.zalloc = (alloc_func)mm_zalloc;
1580: outgoing_stream.zfree = (free_func)mm_zfree;
1581: outgoing_stream.opaque = mm;
1582:
1583: incoming_stream.zalloc = (alloc_func)mm_zalloc;
1584: incoming_stream.zfree = (free_func)mm_zfree;
1585: incoming_stream.opaque = mm;
1586: }
1587:
1588: /* XXX */
1589:
1590: #define FD_CLOSEONEXEC(x) do { \
1591: if (fcntl(x, F_SETFD, 1) == -1) \
1592: fatal("fcntl(%d, F_SETFD)", x); \
1593: } while (0)
1594:
1.2 markus 1595: static void
1.1 provos 1596: monitor_socketpair(int *pair)
1.3 markus 1597: {
1.1 provos 1598: if (socketpair(AF_UNIX, SOCK_STREAM, 0, pair) == -1)
1.14 markus 1599: fatal("%s: socketpair", __func__);
1.1 provos 1600: FD_CLOSEONEXEC(pair[0]);
1601: FD_CLOSEONEXEC(pair[1]);
1602: }
1603:
1604: #define MM_MEMSIZE 65536
1605:
1606: struct monitor *
1607: monitor_init(void)
1608: {
1609: struct monitor *mon;
1610: int pair[2];
1611:
1612: mon = xmalloc(sizeof(*mon));
1613:
1614: monitor_socketpair(pair);
1615:
1616: mon->m_recvfd = pair[0];
1617: mon->m_sendfd = pair[1];
1618:
1619: /* Used to share zlib space across processes */
1.16 djm 1620: if (options.compression) {
1621: mon->m_zback = mm_create(NULL, MM_MEMSIZE);
1622: mon->m_zlib = mm_create(mon->m_zback, 20 * MM_MEMSIZE);
1.1 provos 1623:
1.16 djm 1624: /* Compression needs to share state across borders */
1625: mm_init_compression(mon->m_zlib);
1626: }
1.1 provos 1627:
1628: return mon;
1629: }
1630:
1631: void
1632: monitor_reinit(struct monitor *mon)
1633: {
1634: int pair[2];
1635:
1636: monitor_socketpair(pair);
1637:
1638: mon->m_recvfd = pair[0];
1639: mon->m_sendfd = pair[1];
1640: }
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