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