Annotation of src/usr.bin/ssh/monitor.c, Revision 1.66
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"
1.66 ! stevesk 28: RCSID("$OpenBSD: monitor.c,v 1.65 2006/02/08 12:15:27 stevesk Exp $");
1.1 provos 29:
1.65 stevesk 30: #include <paths.h>
1.1 provos 31:
32: #ifdef SKEY
33: #include <skey.h>
34: #endif
1.65 stevesk 35:
36: #include <openssl/dh.h>
1.1 provos 37:
38: #include "ssh.h"
39: #include "auth.h"
40: #include "kex.h"
41: #include "dh.h"
42: #include "zlib.h"
43: #include "packet.h"
44: #include "auth-options.h"
45: #include "sshpty.h"
46: #include "channels.h"
47: #include "session.h"
48: #include "sshlogin.h"
49: #include "canohost.h"
50: #include "log.h"
51: #include "servconf.h"
52: #include "monitor.h"
53: #include "monitor_mm.h"
54: #include "monitor_wrap.h"
55: #include "monitor_fdpass.h"
56: #include "xmalloc.h"
57: #include "misc.h"
58: #include "buffer.h"
59: #include "bufaux.h"
60: #include "compat.h"
61: #include "ssh2.h"
62:
1.46 markus 63: #ifdef GSSAPI
64: #include "ssh-gss.h"
65: static Gssctxt *gsscontext = NULL;
66: #endif
67:
1.1 provos 68: /* Imports */
69: extern ServerOptions options;
70: extern u_int utmp_len;
71: extern Newkeys *current_keys[];
72: extern z_stream incoming_stream;
73: extern z_stream outgoing_stream;
74: extern u_char session_id[];
75: extern Buffer input, output;
76: extern Buffer auth_debug;
77: extern int auth_debug_init;
1.61 dtucker 78: extern Buffer loginmsg;
1.1 provos 79:
80: /* State exported from the child */
81:
82: struct {
83: z_stream incoming;
84: z_stream outgoing;
85: u_char *keyin;
86: u_int keyinlen;
87: u_char *keyout;
88: u_int keyoutlen;
89: u_char *ivin;
90: u_int ivinlen;
91: u_char *ivout;
92: u_int ivoutlen;
1.15 markus 93: u_char *ssh1key;
94: u_int ssh1keylen;
1.1 provos 95: int ssh1cipher;
96: int ssh1protoflags;
97: u_char *input;
98: u_int ilen;
99: u_char *output;
100: u_int olen;
101: } child_state;
102:
1.43 markus 103: /* Functions on the monitor that answer unprivileged requests */
1.1 provos 104:
105: int mm_answer_moduli(int, Buffer *);
106: int mm_answer_sign(int, Buffer *);
107: int mm_answer_pwnamallow(int, Buffer *);
1.10 djm 108: int mm_answer_auth2_read_banner(int, Buffer *);
1.1 provos 109: int mm_answer_authserv(int, Buffer *);
110: int mm_answer_authpassword(int, Buffer *);
111: int mm_answer_bsdauthquery(int, Buffer *);
112: int mm_answer_bsdauthrespond(int, Buffer *);
113: int mm_answer_skeyquery(int, Buffer *);
114: int mm_answer_skeyrespond(int, Buffer *);
115: int mm_answer_keyallowed(int, Buffer *);
116: int mm_answer_keyverify(int, Buffer *);
117: int mm_answer_pty(int, Buffer *);
118: int mm_answer_pty_cleanup(int, Buffer *);
119: int mm_answer_term(int, Buffer *);
120: int mm_answer_rsa_keyallowed(int, Buffer *);
121: int mm_answer_rsa_challenge(int, Buffer *);
122: int mm_answer_rsa_response(int, Buffer *);
123: int mm_answer_sesskey(int, Buffer *);
124: int mm_answer_sessid(int, Buffer *);
125:
1.46 markus 126: #ifdef GSSAPI
127: int mm_answer_gss_setup_ctx(int, Buffer *);
128: int mm_answer_gss_accept_ctx(int, Buffer *);
129: int mm_answer_gss_userok(int, Buffer *);
1.52 markus 130: int mm_answer_gss_checkmic(int, Buffer *);
1.46 markus 131: #endif
1.25 itojun 132:
1.1 provos 133: static Authctxt *authctxt;
134: static BIGNUM *ssh1_challenge = NULL; /* used for ssh1 rsa auth */
135:
136: /* local state for key verify */
137: static u_char *key_blob = NULL;
138: static u_int key_bloblen = 0;
139: static int key_blobtype = MM_NOKEY;
1.26 markus 140: static char *hostbased_cuser = NULL;
141: static char *hostbased_chost = NULL;
1.1 provos 142: static char *auth_method = "unknown";
1.44 markus 143: static u_int session_id2_len = 0;
1.13 markus 144: static u_char *session_id2 = NULL;
1.40 markus 145: static pid_t monitor_child_pid;
1.1 provos 146:
147: struct mon_table {
148: enum monitor_reqtype type;
149: int flags;
150: int (*f)(int, Buffer *);
151: };
152:
153: #define MON_ISAUTH 0x0004 /* Required for Authentication */
154: #define MON_AUTHDECIDE 0x0008 /* Decides Authentication */
155: #define MON_ONCE 0x0010 /* Disable after calling */
156:
157: #define MON_AUTH (MON_ISAUTH|MON_AUTHDECIDE)
158:
159: #define MON_PERMIT 0x1000 /* Request is permitted */
160:
161: struct mon_table mon_dispatch_proto20[] = {
162: {MONITOR_REQ_MODULI, MON_ONCE, mm_answer_moduli},
163: {MONITOR_REQ_SIGN, MON_ONCE, mm_answer_sign},
164: {MONITOR_REQ_PWNAM, MON_ONCE, mm_answer_pwnamallow},
165: {MONITOR_REQ_AUTHSERV, MON_ONCE, mm_answer_authserv},
1.10 djm 166: {MONITOR_REQ_AUTH2_READ_BANNER, MON_ONCE, mm_answer_auth2_read_banner},
1.1 provos 167: {MONITOR_REQ_AUTHPASSWORD, MON_AUTH, mm_answer_authpassword},
168: #ifdef BSD_AUTH
169: {MONITOR_REQ_BSDAUTHQUERY, MON_ISAUTH, mm_answer_bsdauthquery},
1.66 ! stevesk 170: {MONITOR_REQ_BSDAUTHRESPOND, MON_AUTH, mm_answer_bsdauthrespond},
1.1 provos 171: #endif
172: #ifdef SKEY
173: {MONITOR_REQ_SKEYQUERY, MON_ISAUTH, mm_answer_skeyquery},
174: {MONITOR_REQ_SKEYRESPOND, MON_AUTH, mm_answer_skeyrespond},
175: #endif
176: {MONITOR_REQ_KEYALLOWED, MON_ISAUTH, mm_answer_keyallowed},
177: {MONITOR_REQ_KEYVERIFY, MON_AUTH, mm_answer_keyverify},
1.46 markus 178: #ifdef GSSAPI
179: {MONITOR_REQ_GSSSETUP, MON_ISAUTH, mm_answer_gss_setup_ctx},
180: {MONITOR_REQ_GSSSTEP, MON_ISAUTH, mm_answer_gss_accept_ctx},
181: {MONITOR_REQ_GSSUSEROK, MON_AUTH, mm_answer_gss_userok},
1.52 markus 182: {MONITOR_REQ_GSSCHECKMIC, MON_ISAUTH, mm_answer_gss_checkmic},
1.46 markus 183: #endif
1.1 provos 184: {0, 0, NULL}
185: };
186:
187: struct mon_table mon_dispatch_postauth20[] = {
188: {MONITOR_REQ_MODULI, 0, mm_answer_moduli},
189: {MONITOR_REQ_SIGN, 0, mm_answer_sign},
190: {MONITOR_REQ_PTY, 0, mm_answer_pty},
191: {MONITOR_REQ_PTYCLEANUP, 0, mm_answer_pty_cleanup},
192: {MONITOR_REQ_TERM, 0, mm_answer_term},
193: {0, 0, NULL}
194: };
195:
196: struct mon_table mon_dispatch_proto15[] = {
197: {MONITOR_REQ_PWNAM, MON_ONCE, mm_answer_pwnamallow},
198: {MONITOR_REQ_SESSKEY, MON_ONCE, mm_answer_sesskey},
199: {MONITOR_REQ_SESSID, MON_ONCE, mm_answer_sessid},
200: {MONITOR_REQ_AUTHPASSWORD, MON_AUTH, mm_answer_authpassword},
201: {MONITOR_REQ_RSAKEYALLOWED, MON_ISAUTH, mm_answer_rsa_keyallowed},
202: {MONITOR_REQ_KEYALLOWED, MON_ISAUTH, mm_answer_keyallowed},
203: {MONITOR_REQ_RSACHALLENGE, MON_ONCE, mm_answer_rsa_challenge},
204: {MONITOR_REQ_RSARESPONSE, MON_ONCE|MON_AUTHDECIDE, mm_answer_rsa_response},
205: #ifdef BSD_AUTH
206: {MONITOR_REQ_BSDAUTHQUERY, MON_ISAUTH, mm_answer_bsdauthquery},
1.66 ! stevesk 207: {MONITOR_REQ_BSDAUTHRESPOND, MON_AUTH, mm_answer_bsdauthrespond},
1.1 provos 208: #endif
209: #ifdef SKEY
210: {MONITOR_REQ_SKEYQUERY, MON_ISAUTH, mm_answer_skeyquery},
211: {MONITOR_REQ_SKEYRESPOND, MON_AUTH, mm_answer_skeyrespond},
212: #endif
213: {0, 0, NULL}
214: };
215:
216: struct mon_table mon_dispatch_postauth15[] = {
217: {MONITOR_REQ_PTY, MON_ONCE, mm_answer_pty},
218: {MONITOR_REQ_PTYCLEANUP, MON_ONCE, mm_answer_pty_cleanup},
219: {MONITOR_REQ_TERM, 0, mm_answer_term},
220: {0, 0, NULL}
221: };
222:
223: struct mon_table *mon_dispatch;
224:
225: /* Specifies if a certain message is allowed at the moment */
226:
227: static void
228: monitor_permit(struct mon_table *ent, enum monitor_reqtype type, int permit)
229: {
230: while (ent->f != NULL) {
231: if (ent->type == type) {
232: ent->flags &= ~MON_PERMIT;
233: ent->flags |= permit ? MON_PERMIT : 0;
234: return;
235: }
236: ent++;
237: }
238: }
239:
240: static void
241: monitor_permit_authentications(int permit)
242: {
243: struct mon_table *ent = mon_dispatch;
244:
245: while (ent->f != NULL) {
246: if (ent->flags & MON_AUTH) {
247: ent->flags &= ~MON_PERMIT;
248: ent->flags |= permit ? MON_PERMIT : 0;
249: }
250: ent++;
251: }
252: }
253:
1.50 markus 254: void
255: monitor_child_preauth(Authctxt *_authctxt, struct monitor *pmonitor)
1.1 provos 256: {
257: struct mon_table *ent;
258: int authenticated = 0;
259:
260: debug3("preauth child monitor started");
261:
1.50 markus 262: authctxt = _authctxt;
263: memset(authctxt, 0, sizeof(*authctxt));
264:
1.1 provos 265: if (compat20) {
266: mon_dispatch = mon_dispatch_proto20;
267:
268: /* Permit requests for moduli and signatures */
269: monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
270: monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
271: } else {
272: mon_dispatch = mon_dispatch_proto15;
273:
274: monitor_permit(mon_dispatch, MONITOR_REQ_SESSKEY, 1);
275: }
276:
277: /* The first few requests do not require asynchronous access */
278: while (!authenticated) {
1.11 mouring 279: authenticated = monitor_read(pmonitor, mon_dispatch, &ent);
1.1 provos 280: if (authenticated) {
281: if (!(ent->flags & MON_AUTHDECIDE))
282: fatal("%s: unexpected authentication from %d",
1.14 markus 283: __func__, ent->type);
1.1 provos 284: if (authctxt->pw->pw_uid == 0 &&
285: !auth_root_allowed(auth_method))
286: authenticated = 0;
287: }
288:
289: if (ent->flags & MON_AUTHDECIDE) {
290: auth_log(authctxt, authenticated, auth_method,
291: compat20 ? " ssh2" : "");
292: if (!authenticated)
293: authctxt->failures++;
294: }
295: }
296:
297: if (!authctxt->valid)
1.14 markus 298: fatal("%s: authenticated invalid user", __func__);
1.1 provos 299:
300: debug("%s: %s has been authenticated by privileged process",
1.14 markus 301: __func__, authctxt->user);
1.1 provos 302:
1.11 mouring 303: mm_get_keystate(pmonitor);
1.1 provos 304: }
305:
1.40 markus 306: static void
307: monitor_set_child_handler(pid_t pid)
308: {
309: monitor_child_pid = pid;
310: }
311:
312: static void
1.59 avsm 313: monitor_child_handler(int sig)
1.40 markus 314: {
1.59 avsm 315: kill(monitor_child_pid, sig);
1.40 markus 316: }
317:
1.1 provos 318: void
1.11 mouring 319: monitor_child_postauth(struct monitor *pmonitor)
1.1 provos 320: {
1.40 markus 321: monitor_set_child_handler(pmonitor->m_pid);
322: signal(SIGHUP, &monitor_child_handler);
323: signal(SIGTERM, &monitor_child_handler);
324:
1.1 provos 325: if (compat20) {
326: mon_dispatch = mon_dispatch_postauth20;
327:
328: /* Permit requests for moduli and signatures */
329: monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
330: monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
331: monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1);
332: } else {
333: mon_dispatch = mon_dispatch_postauth15;
334: monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1);
335: }
336: if (!no_pty_flag) {
337: monitor_permit(mon_dispatch, MONITOR_REQ_PTY, 1);
338: monitor_permit(mon_dispatch, MONITOR_REQ_PTYCLEANUP, 1);
339: }
340:
341: for (;;)
1.11 mouring 342: monitor_read(pmonitor, mon_dispatch, NULL);
1.1 provos 343: }
344:
345: void
1.11 mouring 346: monitor_sync(struct monitor *pmonitor)
1.1 provos 347: {
1.16 djm 348: if (options.compression) {
349: /* The member allocation is not visible, so sync it */
350: mm_share_sync(&pmonitor->m_zlib, &pmonitor->m_zback);
351: }
1.1 provos 352: }
353:
354: int
1.11 mouring 355: monitor_read(struct monitor *pmonitor, struct mon_table *ent,
1.1 provos 356: struct mon_table **pent)
357: {
358: Buffer m;
359: int ret;
360: u_char type;
361:
362: buffer_init(&m);
363:
1.11 mouring 364: mm_request_receive(pmonitor->m_sendfd, &m);
1.1 provos 365: type = buffer_get_char(&m);
366:
1.14 markus 367: debug3("%s: checking request %d", __func__, type);
1.1 provos 368:
369: while (ent->f != NULL) {
370: if (ent->type == type)
371: break;
372: ent++;
373: }
374:
375: if (ent->f != NULL) {
376: if (!(ent->flags & MON_PERMIT))
1.14 markus 377: fatal("%s: unpermitted request %d", __func__,
1.1 provos 378: type);
1.11 mouring 379: ret = (*ent->f)(pmonitor->m_sendfd, &m);
1.1 provos 380: buffer_free(&m);
381:
382: /* The child may use this request only once, disable it */
383: if (ent->flags & MON_ONCE) {
1.14 markus 384: debug2("%s: %d used once, disabling now", __func__,
1.1 provos 385: type);
386: ent->flags &= ~MON_PERMIT;
387: }
388:
389: if (pent != NULL)
390: *pent = ent;
1.3 markus 391:
1.1 provos 392: return ret;
393: }
394:
1.14 markus 395: fatal("%s: unsupported request: %d", __func__, type);
1.1 provos 396:
397: /* NOTREACHED */
398: return (-1);
399: }
400:
401: /* allowed key state */
402: static int
403: monitor_allowed_key(u_char *blob, u_int bloblen)
404: {
405: /* make sure key is allowed */
406: if (key_blob == NULL || key_bloblen != bloblen ||
407: memcmp(key_blob, blob, key_bloblen))
408: return (0);
409: return (1);
410: }
411:
412: static void
413: monitor_reset_key_state(void)
414: {
415: /* reset state */
416: if (key_blob != NULL)
417: xfree(key_blob);
418: if (hostbased_cuser != NULL)
419: xfree(hostbased_cuser);
420: if (hostbased_chost != NULL)
421: xfree(hostbased_chost);
422: key_blob = NULL;
423: key_bloblen = 0;
424: key_blobtype = MM_NOKEY;
425: hostbased_cuser = NULL;
426: hostbased_chost = NULL;
427: }
428:
429: int
1.59 avsm 430: mm_answer_moduli(int sock, Buffer *m)
1.1 provos 431: {
432: DH *dh;
433: int min, want, max;
434:
435: min = buffer_get_int(m);
436: want = buffer_get_int(m);
437: max = buffer_get_int(m);
438:
439: debug3("%s: got parameters: %d %d %d",
1.14 markus 440: __func__, min, want, max);
1.1 provos 441: /* We need to check here, too, in case the child got corrupted */
442: if (max < min || want < min || max < want)
443: fatal("%s: bad parameters: %d %d %d",
1.14 markus 444: __func__, min, want, max);
1.1 provos 445:
446: buffer_clear(m);
447:
448: dh = choose_dh(min, want, max);
449: if (dh == NULL) {
450: buffer_put_char(m, 0);
451: return (0);
452: } else {
453: /* Send first bignum */
454: buffer_put_char(m, 1);
455: buffer_put_bignum2(m, dh->p);
456: buffer_put_bignum2(m, dh->g);
1.3 markus 457:
1.1 provos 458: DH_free(dh);
459: }
1.59 avsm 460: mm_request_send(sock, MONITOR_ANS_MODULI, m);
1.1 provos 461: return (0);
462: }
463:
464: int
1.59 avsm 465: mm_answer_sign(int sock, Buffer *m)
1.1 provos 466: {
467: Key *key;
468: u_char *p;
469: u_char *signature;
470: u_int siglen, datlen;
471: int keyid;
1.3 markus 472:
1.14 markus 473: debug3("%s", __func__);
1.1 provos 474:
1.3 markus 475: keyid = buffer_get_int(m);
476: p = buffer_get_string(m, &datlen);
1.1 provos 477:
478: if (datlen != 20)
1.19 deraadt 479: fatal("%s: data length incorrect: %u", __func__, datlen);
1.1 provos 480:
1.13 markus 481: /* save session id, it will be passed on the first call */
482: if (session_id2_len == 0) {
483: session_id2_len = datlen;
484: session_id2 = xmalloc(session_id2_len);
485: memcpy(session_id2, p, session_id2_len);
486: }
487:
1.1 provos 488: if ((key = get_hostkey_by_index(keyid)) == NULL)
1.14 markus 489: fatal("%s: no hostkey from index %d", __func__, keyid);
1.1 provos 490: if (key_sign(key, &signature, &siglen, p, datlen) < 0)
1.14 markus 491: fatal("%s: key_sign failed", __func__);
1.1 provos 492:
1.19 deraadt 493: debug3("%s: signature %p(%u)", __func__, signature, siglen);
1.1 provos 494:
495: buffer_clear(m);
496: buffer_put_string(m, signature, siglen);
497:
498: xfree(p);
499: xfree(signature);
500:
1.59 avsm 501: mm_request_send(sock, MONITOR_ANS_SIGN, m);
1.1 provos 502:
503: /* Turn on permissions for getpwnam */
504: monitor_permit(mon_dispatch, MONITOR_REQ_PWNAM, 1);
505:
506: return (0);
507: }
508:
509: /* Retrieves the password entry and also checks if the user is permitted */
510:
511: int
1.59 avsm 512: mm_answer_pwnamallow(int sock, Buffer *m)
1.1 provos 513: {
1.60 dtucker 514: char *username;
1.1 provos 515: struct passwd *pwent;
516: int allowed = 0;
1.3 markus 517:
1.14 markus 518: debug3("%s", __func__);
1.1 provos 519:
520: if (authctxt->attempt++ != 0)
1.14 markus 521: fatal("%s: multiple attempts for getpwnam", __func__);
1.1 provos 522:
1.60 dtucker 523: username = buffer_get_string(m, NULL);
1.1 provos 524:
1.60 dtucker 525: pwent = getpwnamallow(username);
1.1 provos 526:
1.60 dtucker 527: authctxt->user = xstrdup(username);
528: setproctitle("%s [priv]", pwent ? username : "unknown");
529: xfree(username);
1.1 provos 530:
531: buffer_clear(m);
532:
533: if (pwent == NULL) {
534: buffer_put_char(m, 0);
1.53 djm 535: authctxt->pw = fakepw();
1.1 provos 536: goto out;
537: }
538:
539: allowed = 1;
1.4 markus 540: authctxt->pw = pwent;
1.1 provos 541: authctxt->valid = 1;
542:
543: buffer_put_char(m, 1);
544: buffer_put_string(m, pwent, sizeof(struct passwd));
545: buffer_put_cstring(m, pwent->pw_name);
546: buffer_put_cstring(m, "*");
547: buffer_put_cstring(m, pwent->pw_gecos);
548: buffer_put_cstring(m, pwent->pw_class);
549: buffer_put_cstring(m, pwent->pw_dir);
550: buffer_put_cstring(m, pwent->pw_shell);
551:
552: out:
1.14 markus 553: debug3("%s: sending MONITOR_ANS_PWNAM: %d", __func__, allowed);
1.59 avsm 554: mm_request_send(sock, MONITOR_ANS_PWNAM, m);
1.1 provos 555:
556: /* For SSHv1 allow authentication now */
557: if (!compat20)
558: monitor_permit_authentications(1);
1.10 djm 559: else {
1.1 provos 560: /* Allow service/style information on the auth context */
561: monitor_permit(mon_dispatch, MONITOR_REQ_AUTHSERV, 1);
1.10 djm 562: monitor_permit(mon_dispatch, MONITOR_REQ_AUTH2_READ_BANNER, 1);
563: }
564:
565:
566: return (0);
567: }
568:
1.59 avsm 569: int mm_answer_auth2_read_banner(int sock, Buffer *m)
1.10 djm 570: {
571: char *banner;
572:
573: buffer_clear(m);
574: banner = auth2_read_banner();
575: buffer_put_cstring(m, banner != NULL ? banner : "");
1.59 avsm 576: mm_request_send(sock, MONITOR_ANS_AUTH2_READ_BANNER, m);
1.1 provos 577:
1.10 djm 578: if (banner != NULL)
1.21 deraadt 579: xfree(banner);
1.1 provos 580:
581: return (0);
582: }
583:
584: int
1.59 avsm 585: mm_answer_authserv(int sock, Buffer *m)
1.1 provos 586: {
587: monitor_permit_authentications(1);
588:
589: authctxt->service = buffer_get_string(m, NULL);
590: authctxt->style = buffer_get_string(m, NULL);
1.6 stevesk 591: debug3("%s: service=%s, style=%s",
1.14 markus 592: __func__, authctxt->service, authctxt->style);
1.6 stevesk 593:
1.1 provos 594: if (strlen(authctxt->style) == 0) {
595: xfree(authctxt->style);
596: authctxt->style = NULL;
597: }
598:
599: return (0);
600: }
601:
602: int
1.59 avsm 603: mm_answer_authpassword(int sock, Buffer *m)
1.1 provos 604: {
605: static int call_count;
606: char *passwd;
1.22 stevesk 607: int authenticated;
608: u_int plen;
1.1 provos 609:
610: passwd = buffer_get_string(m, &plen);
611: /* Only authenticate if the context is valid */
1.12 markus 612: authenticated = options.password_authentication &&
1.48 markus 613: auth_password(authctxt, passwd);
1.1 provos 614: memset(passwd, 0, strlen(passwd));
615: xfree(passwd);
616:
617: buffer_clear(m);
618: buffer_put_int(m, authenticated);
619:
1.14 markus 620: debug3("%s: sending result %d", __func__, authenticated);
1.59 avsm 621: mm_request_send(sock, MONITOR_ANS_AUTHPASSWORD, m);
1.1 provos 622:
623: call_count++;
624: if (plen == 0 && call_count == 1)
625: auth_method = "none";
626: else
627: auth_method = "password";
628:
629: /* Causes monitor loop to terminate if authenticated */
630: return (authenticated);
631: }
632:
633: #ifdef BSD_AUTH
634: int
1.59 avsm 635: mm_answer_bsdauthquery(int sock, Buffer *m)
1.1 provos 636: {
637: char *name, *infotxt;
638: u_int numprompts;
639: u_int *echo_on;
640: char **prompts;
1.31 markus 641: u_int success;
1.1 provos 642:
1.31 markus 643: success = bsdauth_query(authctxt, &name, &infotxt, &numprompts,
644: &prompts, &echo_on) < 0 ? 0 : 1;
1.1 provos 645:
646: buffer_clear(m);
1.31 markus 647: buffer_put_int(m, success);
648: if (success)
1.1 provos 649: buffer_put_cstring(m, prompts[0]);
650:
1.31 markus 651: debug3("%s: sending challenge success: %u", __func__, success);
1.59 avsm 652: mm_request_send(sock, MONITOR_ANS_BSDAUTHQUERY, m);
1.1 provos 653:
1.31 markus 654: if (success) {
1.1 provos 655: xfree(name);
656: xfree(infotxt);
657: xfree(prompts);
658: xfree(echo_on);
659: }
660:
661: return (0);
662: }
663:
664: int
1.59 avsm 665: mm_answer_bsdauthrespond(int sock, Buffer *m)
1.1 provos 666: {
667: char *response;
668: int authok;
669:
670: if (authctxt->as == 0)
1.14 markus 671: fatal("%s: no bsd auth session", __func__);
1.1 provos 672:
673: response = buffer_get_string(m, NULL);
1.12 markus 674: authok = options.challenge_response_authentication &&
675: auth_userresponse(authctxt->as, response, 0);
1.1 provos 676: authctxt->as = NULL;
1.14 markus 677: debug3("%s: <%s> = <%d>", __func__, response, authok);
1.1 provos 678: xfree(response);
679:
680: buffer_clear(m);
681: buffer_put_int(m, authok);
682:
1.14 markus 683: debug3("%s: sending authenticated: %d", __func__, authok);
1.59 avsm 684: mm_request_send(sock, MONITOR_ANS_BSDAUTHRESPOND, m);
1.1 provos 685:
686: auth_method = "bsdauth";
687:
688: return (authok != 0);
689: }
690: #endif
691:
692: #ifdef SKEY
693: int
1.59 avsm 694: mm_answer_skeyquery(int sock, Buffer *m)
1.1 provos 695: {
696: struct skey skey;
697: char challenge[1024];
1.31 markus 698: u_int success;
1.1 provos 699:
1.31 markus 700: success = skeychallenge(&skey, authctxt->user, challenge) < 0 ? 0 : 1;
1.1 provos 701:
702: buffer_clear(m);
1.31 markus 703: buffer_put_int(m, success);
704: if (success)
1.1 provos 705: buffer_put_cstring(m, challenge);
706:
1.31 markus 707: debug3("%s: sending challenge success: %u", __func__, success);
1.59 avsm 708: mm_request_send(sock, MONITOR_ANS_SKEYQUERY, m);
1.1 provos 709:
710: return (0);
711: }
712:
713: int
1.59 avsm 714: mm_answer_skeyrespond(int sock, Buffer *m)
1.1 provos 715: {
716: char *response;
717: int authok;
718:
719: response = buffer_get_string(m, NULL);
720:
1.12 markus 721: authok = (options.challenge_response_authentication &&
722: authctxt->valid &&
1.1 provos 723: skey_haskey(authctxt->pw->pw_name) == 0 &&
724: skey_passcheck(authctxt->pw->pw_name, response) != -1);
725:
726: xfree(response);
727:
728: buffer_clear(m);
729: buffer_put_int(m, authok);
730:
1.14 markus 731: debug3("%s: sending authenticated: %d", __func__, authok);
1.59 avsm 732: mm_request_send(sock, MONITOR_ANS_SKEYRESPOND, m);
1.1 provos 733:
734: auth_method = "skey";
735:
736: return (authok != 0);
737: }
738: #endif
739:
1.2 markus 740: static void
1.1 provos 741: mm_append_debug(Buffer *m)
742: {
743: if (auth_debug_init && buffer_len(&auth_debug)) {
1.14 markus 744: debug3("%s: Appending debug messages for child", __func__);
1.1 provos 745: buffer_append(m, buffer_ptr(&auth_debug),
746: buffer_len(&auth_debug));
747: buffer_clear(&auth_debug);
748: }
749: }
750:
751: int
1.59 avsm 752: mm_answer_keyallowed(int sock, Buffer *m)
1.1 provos 753: {
754: Key *key;
1.26 markus 755: char *cuser, *chost;
756: u_char *blob;
1.1 provos 757: u_int bloblen;
758: enum mm_keytype type = 0;
759: int allowed = 0;
760:
1.14 markus 761: debug3("%s entering", __func__);
1.3 markus 762:
1.1 provos 763: type = buffer_get_int(m);
764: cuser = buffer_get_string(m, NULL);
765: chost = buffer_get_string(m, NULL);
766: blob = buffer_get_string(m, &bloblen);
767:
768: key = key_from_blob(blob, bloblen);
769:
770: if ((compat20 && type == MM_RSAHOSTKEY) ||
771: (!compat20 && type != MM_RSAHOSTKEY))
1.14 markus 772: fatal("%s: key type and protocol mismatch", __func__);
1.1 provos 773:
1.14 markus 774: debug3("%s: key_from_blob: %p", __func__, key);
1.1 provos 775:
1.51 djm 776: if (key != NULL && authctxt->valid) {
1.63 deraadt 777: switch (type) {
1.1 provos 778: case MM_USERKEY:
1.12 markus 779: allowed = options.pubkey_authentication &&
780: user_key_allowed(authctxt->pw, key);
1.1 provos 781: break;
782: case MM_HOSTKEY:
1.12 markus 783: allowed = options.hostbased_authentication &&
784: hostbased_key_allowed(authctxt->pw,
1.1 provos 785: cuser, chost, key);
786: break;
787: case MM_RSAHOSTKEY:
788: key->type = KEY_RSA1; /* XXX */
1.12 markus 789: allowed = options.rhosts_rsa_authentication &&
790: auth_rhosts_rsa_key_allowed(authctxt->pw,
1.1 provos 791: cuser, chost, key);
792: break;
793: default:
1.14 markus 794: fatal("%s: unknown key type %d", __func__, type);
1.1 provos 795: break;
796: }
1.33 markus 797: }
798: if (key != NULL)
1.1 provos 799: key_free(key);
800:
801: /* clear temporarily storage (used by verify) */
802: monitor_reset_key_state();
803:
804: if (allowed) {
805: /* Save temporarily for comparison in verify */
806: key_blob = blob;
807: key_bloblen = bloblen;
808: key_blobtype = type;
809: hostbased_cuser = cuser;
810: hostbased_chost = chost;
811: }
812:
813: debug3("%s: key %p is %s",
1.14 markus 814: __func__, key, allowed ? "allowed" : "disallowed");
1.1 provos 815:
816: buffer_clear(m);
817: buffer_put_int(m, allowed);
1.32 markus 818: buffer_put_int(m, forced_command != NULL);
1.1 provos 819:
820: mm_append_debug(m);
821:
1.59 avsm 822: mm_request_send(sock, MONITOR_ANS_KEYALLOWED, m);
1.1 provos 823:
824: if (type == MM_RSAHOSTKEY)
825: monitor_permit(mon_dispatch, MONITOR_REQ_RSACHALLENGE, allowed);
826:
827: return (0);
828: }
829:
830: static int
831: monitor_valid_userblob(u_char *data, u_int datalen)
832: {
833: Buffer b;
1.26 markus 834: char *p;
1.1 provos 835: u_int len;
836: int fail = 0;
837:
838: buffer_init(&b);
839: buffer_append(&b, data, datalen);
1.3 markus 840:
1.1 provos 841: if (datafellows & SSH_OLD_SESSIONID) {
1.13 markus 842: p = buffer_ptr(&b);
843: len = buffer_len(&b);
844: if ((session_id2 == NULL) ||
845: (len < session_id2_len) ||
846: (memcmp(p, session_id2, session_id2_len) != 0))
847: fail++;
1.1 provos 848: buffer_consume(&b, session_id2_len);
849: } else {
1.13 markus 850: p = buffer_get_string(&b, &len);
851: if ((session_id2 == NULL) ||
852: (len != session_id2_len) ||
853: (memcmp(p, session_id2, session_id2_len) != 0))
1.1 provos 854: fail++;
1.13 markus 855: xfree(p);
1.1 provos 856: }
857: if (buffer_get_char(&b) != SSH2_MSG_USERAUTH_REQUEST)
858: fail++;
859: p = buffer_get_string(&b, NULL);
860: if (strcmp(authctxt->user, p) != 0) {
1.38 itojun 861: logit("wrong user name passed to monitor: expected %s != %.100s",
1.1 provos 862: authctxt->user, p);
863: fail++;
864: }
865: xfree(p);
866: buffer_skip_string(&b);
867: if (datafellows & SSH_BUG_PKAUTH) {
868: if (!buffer_get_char(&b))
869: fail++;
870: } else {
871: p = buffer_get_string(&b, NULL);
872: if (strcmp("publickey", p) != 0)
873: fail++;
874: xfree(p);
875: if (!buffer_get_char(&b))
876: fail++;
877: buffer_skip_string(&b);
878: }
879: buffer_skip_string(&b);
880: if (buffer_len(&b) != 0)
881: fail++;
882: buffer_free(&b);
883: return (fail == 0);
884: }
885:
886: static int
1.26 markus 887: monitor_valid_hostbasedblob(u_char *data, u_int datalen, char *cuser,
888: char *chost)
1.1 provos 889: {
890: Buffer b;
1.26 markus 891: char *p;
1.1 provos 892: u_int len;
893: int fail = 0;
894:
895: buffer_init(&b);
896: buffer_append(&b, data, datalen);
1.3 markus 897:
1.13 markus 898: p = buffer_get_string(&b, &len);
899: if ((session_id2 == NULL) ||
900: (len != session_id2_len) ||
901: (memcmp(p, session_id2, session_id2_len) != 0))
1.1 provos 902: fail++;
1.13 markus 903: xfree(p);
904:
1.1 provos 905: if (buffer_get_char(&b) != SSH2_MSG_USERAUTH_REQUEST)
906: fail++;
907: p = buffer_get_string(&b, NULL);
908: if (strcmp(authctxt->user, p) != 0) {
1.38 itojun 909: logit("wrong user name passed to monitor: expected %s != %.100s",
1.1 provos 910: authctxt->user, p);
911: fail++;
912: }
913: xfree(p);
914: buffer_skip_string(&b); /* service */
915: p = buffer_get_string(&b, NULL);
916: if (strcmp(p, "hostbased") != 0)
917: fail++;
918: xfree(p);
919: buffer_skip_string(&b); /* pkalg */
920: buffer_skip_string(&b); /* pkblob */
921:
922: /* verify client host, strip trailing dot if necessary */
923: p = buffer_get_string(&b, NULL);
924: if (((len = strlen(p)) > 0) && p[len - 1] == '.')
925: p[len - 1] = '\0';
926: if (strcmp(p, chost) != 0)
927: fail++;
928: xfree(p);
929:
930: /* verify client user */
931: p = buffer_get_string(&b, NULL);
932: if (strcmp(p, cuser) != 0)
933: fail++;
934: xfree(p);
935:
936: if (buffer_len(&b) != 0)
937: fail++;
938: buffer_free(&b);
939: return (fail == 0);
940: }
941:
942: int
1.59 avsm 943: mm_answer_keyverify(int sock, Buffer *m)
1.1 provos 944: {
945: Key *key;
946: u_char *signature, *data, *blob;
947: u_int signaturelen, datalen, bloblen;
948: int verified = 0;
949: int valid_data = 0;
950:
951: blob = buffer_get_string(m, &bloblen);
952: signature = buffer_get_string(m, &signaturelen);
953: data = buffer_get_string(m, &datalen);
954:
955: if (hostbased_cuser == NULL || hostbased_chost == NULL ||
1.8 mouring 956: !monitor_allowed_key(blob, bloblen))
1.14 markus 957: fatal("%s: bad key, not previously allowed", __func__);
1.1 provos 958:
959: key = key_from_blob(blob, bloblen);
960: if (key == NULL)
1.14 markus 961: fatal("%s: bad public key blob", __func__);
1.1 provos 962:
963: switch (key_blobtype) {
964: case MM_USERKEY:
965: valid_data = monitor_valid_userblob(data, datalen);
966: break;
967: case MM_HOSTKEY:
968: valid_data = monitor_valid_hostbasedblob(data, datalen,
969: hostbased_cuser, hostbased_chost);
970: break;
971: default:
972: valid_data = 0;
973: break;
974: }
975: if (!valid_data)
1.14 markus 976: fatal("%s: bad signature data blob", __func__);
1.1 provos 977:
978: verified = key_verify(key, signature, signaturelen, data, datalen);
979: debug3("%s: key %p signature %s",
1.14 markus 980: __func__, key, verified ? "verified" : "unverified");
1.1 provos 981:
982: key_free(key);
983: xfree(blob);
984: xfree(signature);
985: xfree(data);
986:
1.17 stevesk 987: auth_method = key_blobtype == MM_USERKEY ? "publickey" : "hostbased";
988:
1.1 provos 989: monitor_reset_key_state();
1.3 markus 990:
1.1 provos 991: buffer_clear(m);
992: buffer_put_int(m, verified);
1.59 avsm 993: mm_request_send(sock, MONITOR_ANS_KEYVERIFY, m);
1.1 provos 994:
995: return (verified);
996: }
997:
1.2 markus 998: static void
1.1 provos 999: mm_record_login(Session *s, struct passwd *pw)
1000: {
1001: socklen_t fromlen;
1002: struct sockaddr_storage from;
1003:
1004: /*
1005: * Get IP address of client. If the connection is not a socket, let
1006: * the address be 0.0.0.0.
1007: */
1008: memset(&from, 0, sizeof(from));
1.24 stevesk 1009: fromlen = sizeof(from);
1.1 provos 1010: if (packet_connection_is_on_socket()) {
1011: if (getpeername(packet_get_connection_in(),
1012: (struct sockaddr *) & from, &fromlen) < 0) {
1013: debug("getpeername: %.100s", strerror(errno));
1.50 markus 1014: cleanup_exit(255);
1.1 provos 1015: }
1016: }
1017: /* Record that there was a login on that tty from the remote host. */
1018: record_login(s->pid, s->tty, pw->pw_name, pw->pw_uid,
1.42 markus 1019: get_remote_name_or_ip(utmp_len, options.use_dns),
1.24 stevesk 1020: (struct sockaddr *)&from, fromlen);
1.1 provos 1021: }
1022:
1023: static void
1024: mm_session_close(Session *s)
1025: {
1.41 djm 1026: debug3("%s: session %d pid %ld", __func__, s->self, (long)s->pid);
1.1 provos 1027: if (s->ttyfd != -1) {
1.14 markus 1028: debug3("%s: tty %s ptyfd %d", __func__, s->tty, s->ptyfd);
1.1 provos 1029: session_pty_cleanup2(s);
1030: }
1031: s->used = 0;
1032: }
1033:
1034: int
1.59 avsm 1035: mm_answer_pty(int sock, Buffer *m)
1.1 provos 1036: {
1.11 mouring 1037: extern struct monitor *pmonitor;
1.1 provos 1038: Session *s;
1039: int res, fd0;
1040:
1.14 markus 1041: debug3("%s entering", __func__);
1.1 provos 1042:
1043: buffer_clear(m);
1044: s = session_new();
1045: if (s == NULL)
1046: goto error;
1047: s->authctxt = authctxt;
1048: s->pw = authctxt->pw;
1.11 mouring 1049: s->pid = pmonitor->m_pid;
1.1 provos 1050: res = pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty));
1051: if (res == 0)
1052: goto error;
1053: pty_setowner(authctxt->pw, s->tty);
1054:
1055: buffer_put_int(m, 1);
1056: buffer_put_cstring(m, s->tty);
1057:
1058: /* We need to trick ttyslot */
1059: if (dup2(s->ttyfd, 0) == -1)
1.14 markus 1060: fatal("%s: dup2", __func__);
1.1 provos 1061:
1062: mm_record_login(s, authctxt->pw);
1063:
1064: /* Now we can close the file descriptor again */
1065: close(0);
1.61 dtucker 1066:
1067: /* send messages generated by record_login */
1068: buffer_put_string(m, buffer_ptr(&loginmsg), buffer_len(&loginmsg));
1069: buffer_clear(&loginmsg);
1070:
1071: mm_request_send(sock, MONITOR_ANS_PTY, m);
1072:
1073: mm_send_fd(sock, s->ptyfd);
1074: mm_send_fd(sock, s->ttyfd);
1.1 provos 1075:
1076: /* make sure nothing uses fd 0 */
1077: if ((fd0 = open(_PATH_DEVNULL, O_RDONLY)) < 0)
1.14 markus 1078: fatal("%s: open(/dev/null): %s", __func__, strerror(errno));
1.1 provos 1079: if (fd0 != 0)
1.14 markus 1080: error("%s: fd0 %d != 0", __func__, fd0);
1.1 provos 1081:
1082: /* slave is not needed */
1083: close(s->ttyfd);
1084: s->ttyfd = s->ptyfd;
1085: /* no need to dup() because nobody closes ptyfd */
1086: s->ptymaster = s->ptyfd;
1087:
1.14 markus 1088: debug3("%s: tty %s ptyfd %d", __func__, s->tty, s->ttyfd);
1.1 provos 1089:
1090: return (0);
1091:
1092: error:
1093: if (s != NULL)
1094: mm_session_close(s);
1095: buffer_put_int(m, 0);
1.59 avsm 1096: mm_request_send(sock, MONITOR_ANS_PTY, m);
1.1 provos 1097: return (0);
1098: }
1099:
1100: int
1.59 avsm 1101: mm_answer_pty_cleanup(int sock, Buffer *m)
1.1 provos 1102: {
1103: Session *s;
1104: char *tty;
1105:
1.14 markus 1106: debug3("%s entering", __func__);
1.1 provos 1107:
1108: tty = buffer_get_string(m, NULL);
1109: if ((s = session_by_tty(tty)) != NULL)
1110: mm_session_close(s);
1111: buffer_clear(m);
1112: xfree(tty);
1113: return (0);
1114: }
1115:
1116: int
1.59 avsm 1117: mm_answer_sesskey(int sock, Buffer *m)
1.1 provos 1118: {
1119: BIGNUM *p;
1120: int rsafail;
1121:
1122: /* Turn off permissions */
1.62 dtucker 1123: monitor_permit(mon_dispatch, MONITOR_REQ_SESSKEY, 0);
1.1 provos 1124:
1125: if ((p = BN_new()) == NULL)
1.14 markus 1126: fatal("%s: BN_new", __func__);
1.1 provos 1127:
1128: buffer_get_bignum2(m, p);
1129:
1130: rsafail = ssh1_session_key(p);
1131:
1132: buffer_clear(m);
1133: buffer_put_int(m, rsafail);
1134: buffer_put_bignum2(m, p);
1135:
1136: BN_clear_free(p);
1137:
1.59 avsm 1138: mm_request_send(sock, MONITOR_ANS_SESSKEY, m);
1.1 provos 1139:
1140: /* Turn on permissions for sessid passing */
1141: monitor_permit(mon_dispatch, MONITOR_REQ_SESSID, 1);
1142:
1143: return (0);
1144: }
1145:
1146: int
1.59 avsm 1147: mm_answer_sessid(int sock, Buffer *m)
1.1 provos 1148: {
1149: int i;
1150:
1.14 markus 1151: debug3("%s entering", __func__);
1.1 provos 1152:
1153: if (buffer_len(m) != 16)
1.14 markus 1154: fatal("%s: bad ssh1 session id", __func__);
1.1 provos 1155: for (i = 0; i < 16; i++)
1156: session_id[i] = buffer_get_char(m);
1157:
1158: /* Turn on permissions for getpwnam */
1159: monitor_permit(mon_dispatch, MONITOR_REQ_PWNAM, 1);
1160:
1161: return (0);
1162: }
1163:
1164: int
1.59 avsm 1165: mm_answer_rsa_keyallowed(int sock, Buffer *m)
1.1 provos 1166: {
1167: BIGNUM *client_n;
1168: Key *key = NULL;
1.3 markus 1169: u_char *blob = NULL;
1170: u_int blen = 0;
1.1 provos 1171: int allowed = 0;
1172:
1.14 markus 1173: debug3("%s entering", __func__);
1.1 provos 1174:
1.12 markus 1175: if (options.rsa_authentication && authctxt->valid) {
1.1 provos 1176: if ((client_n = BN_new()) == NULL)
1.14 markus 1177: fatal("%s: BN_new", __func__);
1.1 provos 1178: buffer_get_bignum2(m, client_n);
1179: allowed = auth_rsa_key_allowed(authctxt->pw, client_n, &key);
1180: BN_clear_free(client_n);
1181: }
1182: buffer_clear(m);
1183: buffer_put_int(m, allowed);
1.32 markus 1184: buffer_put_int(m, forced_command != NULL);
1.1 provos 1185:
1186: /* clear temporarily storage (used by generate challenge) */
1187: monitor_reset_key_state();
1188:
1189: if (allowed && key != NULL) {
1190: key->type = KEY_RSA; /* cheat for key_to_blob */
1191: if (key_to_blob(key, &blob, &blen) == 0)
1.14 markus 1192: fatal("%s: key_to_blob failed", __func__);
1.1 provos 1193: buffer_put_string(m, blob, blen);
1194:
1195: /* Save temporarily for comparison in verify */
1196: key_blob = blob;
1197: key_bloblen = blen;
1198: key_blobtype = MM_RSAUSERKEY;
1.33 markus 1199: }
1200: if (key != NULL)
1.1 provos 1201: key_free(key);
1202:
1203: mm_append_debug(m);
1204:
1.59 avsm 1205: mm_request_send(sock, MONITOR_ANS_RSAKEYALLOWED, m);
1.1 provos 1206:
1207: monitor_permit(mon_dispatch, MONITOR_REQ_RSACHALLENGE, allowed);
1208: monitor_permit(mon_dispatch, MONITOR_REQ_RSARESPONSE, 0);
1209: return (0);
1210: }
1211:
1212: int
1.59 avsm 1213: mm_answer_rsa_challenge(int sock, Buffer *m)
1.1 provos 1214: {
1215: Key *key = NULL;
1.3 markus 1216: u_char *blob;
1217: u_int blen;
1.1 provos 1218:
1.14 markus 1219: debug3("%s entering", __func__);
1.1 provos 1220:
1221: if (!authctxt->valid)
1.14 markus 1222: fatal("%s: authctxt not valid", __func__);
1.1 provos 1223: blob = buffer_get_string(m, &blen);
1224: if (!monitor_allowed_key(blob, blen))
1.14 markus 1225: fatal("%s: bad key, not previously allowed", __func__);
1.1 provos 1226: if (key_blobtype != MM_RSAUSERKEY && key_blobtype != MM_RSAHOSTKEY)
1.14 markus 1227: fatal("%s: key type mismatch", __func__);
1.1 provos 1228: if ((key = key_from_blob(blob, blen)) == NULL)
1.14 markus 1229: fatal("%s: received bad key", __func__);
1.1 provos 1230:
1231: if (ssh1_challenge)
1232: BN_clear_free(ssh1_challenge);
1233: ssh1_challenge = auth_rsa_generate_challenge(key);
1234:
1235: buffer_clear(m);
1236: buffer_put_bignum2(m, ssh1_challenge);
1237:
1.14 markus 1238: debug3("%s sending reply", __func__);
1.59 avsm 1239: mm_request_send(sock, MONITOR_ANS_RSACHALLENGE, m);
1.1 provos 1240:
1241: monitor_permit(mon_dispatch, MONITOR_REQ_RSARESPONSE, 1);
1.33 markus 1242:
1243: xfree(blob);
1244: key_free(key);
1.1 provos 1245: return (0);
1246: }
1247:
1248: int
1.59 avsm 1249: mm_answer_rsa_response(int sock, Buffer *m)
1.1 provos 1250: {
1251: Key *key = NULL;
1.3 markus 1252: u_char *blob, *response;
1253: u_int blen, len;
1254: int success;
1.1 provos 1255:
1.14 markus 1256: debug3("%s entering", __func__);
1.1 provos 1257:
1258: if (!authctxt->valid)
1.14 markus 1259: fatal("%s: authctxt not valid", __func__);
1.1 provos 1260: if (ssh1_challenge == NULL)
1.14 markus 1261: fatal("%s: no ssh1_challenge", __func__);
1.1 provos 1262:
1263: blob = buffer_get_string(m, &blen);
1264: if (!monitor_allowed_key(blob, blen))
1.14 markus 1265: fatal("%s: bad key, not previously allowed", __func__);
1.1 provos 1266: if (key_blobtype != MM_RSAUSERKEY && key_blobtype != MM_RSAHOSTKEY)
1.14 markus 1267: fatal("%s: key type mismatch: %d", __func__, key_blobtype);
1.1 provos 1268: if ((key = key_from_blob(blob, blen)) == NULL)
1.14 markus 1269: fatal("%s: received bad key", __func__);
1.1 provos 1270: response = buffer_get_string(m, &len);
1271: if (len != 16)
1.14 markus 1272: fatal("%s: received bad response to challenge", __func__);
1.1 provos 1273: success = auth_rsa_verify_response(key, ssh1_challenge, response);
1274:
1.33 markus 1275: xfree(blob);
1.1 provos 1276: key_free(key);
1277: xfree(response);
1278:
1279: auth_method = key_blobtype == MM_RSAUSERKEY ? "rsa" : "rhosts-rsa";
1280:
1281: /* reset state */
1282: BN_clear_free(ssh1_challenge);
1283: ssh1_challenge = NULL;
1284: monitor_reset_key_state();
1285:
1286: buffer_clear(m);
1287: buffer_put_int(m, success);
1.59 avsm 1288: mm_request_send(sock, MONITOR_ANS_RSARESPONSE, m);
1.1 provos 1289:
1290: return (success);
1291: }
1292:
1293: int
1.59 avsm 1294: mm_answer_term(int sock, Buffer *req)
1.1 provos 1295: {
1.11 mouring 1296: extern struct monitor *pmonitor;
1.1 provos 1297: int res, status;
1298:
1.14 markus 1299: debug3("%s: tearing down sessions", __func__);
1.1 provos 1300:
1301: /* The child is terminating */
1302: session_destroy_all(&mm_session_close);
1303:
1.11 mouring 1304: while (waitpid(pmonitor->m_pid, &status, 0) == -1)
1.9 markus 1305: if (errno != EINTR)
1306: exit(1);
1.1 provos 1307:
1308: res = WIFEXITED(status) ? WEXITSTATUS(status) : 1;
1309:
1310: /* Terminate process */
1.57 deraadt 1311: exit(res);
1.1 provos 1312: }
1313:
1314: void
1.11 mouring 1315: monitor_apply_keystate(struct monitor *pmonitor)
1.1 provos 1316: {
1317: if (compat20) {
1318: set_newkeys(MODE_IN);
1319: set_newkeys(MODE_OUT);
1320: } else {
1321: packet_set_protocol_flags(child_state.ssh1protoflags);
1.15 markus 1322: packet_set_encryption_key(child_state.ssh1key,
1323: child_state.ssh1keylen, child_state.ssh1cipher);
1324: xfree(child_state.ssh1key);
1.1 provos 1325: }
1326:
1.15 markus 1327: /* for rc4 and other stateful ciphers */
1.1 provos 1328: packet_set_keycontext(MODE_OUT, child_state.keyout);
1329: xfree(child_state.keyout);
1330: packet_set_keycontext(MODE_IN, child_state.keyin);
1331: xfree(child_state.keyin);
1332:
1333: if (!compat20) {
1334: packet_set_iv(MODE_OUT, child_state.ivout);
1335: xfree(child_state.ivout);
1336: packet_set_iv(MODE_IN, child_state.ivin);
1337: xfree(child_state.ivin);
1338: }
1339:
1340: memcpy(&incoming_stream, &child_state.incoming,
1341: sizeof(incoming_stream));
1342: memcpy(&outgoing_stream, &child_state.outgoing,
1343: sizeof(outgoing_stream));
1.3 markus 1344:
1.1 provos 1345: /* Update with new address */
1.16 djm 1346: if (options.compression)
1347: mm_init_compression(pmonitor->m_zlib);
1.1 provos 1348:
1349: /* Network I/O buffers */
1350: /* XXX inefficient for large buffers, need: buffer_init_from_string */
1351: buffer_clear(&input);
1352: buffer_append(&input, child_state.input, child_state.ilen);
1353: memset(child_state.input, 0, child_state.ilen);
1354: xfree(child_state.input);
1355:
1356: buffer_clear(&output);
1357: buffer_append(&output, child_state.output, child_state.olen);
1358: memset(child_state.output, 0, child_state.olen);
1359: xfree(child_state.output);
1360: }
1361:
1.2 markus 1362: static Kex *
1.1 provos 1363: mm_get_kex(Buffer *m)
1364: {
1365: Kex *kex;
1366: void *blob;
1367: u_int bloblen;
1368:
1369: kex = xmalloc(sizeof(*kex));
1370: memset(kex, 0, sizeof(*kex));
1371: kex->session_id = buffer_get_string(m, &kex->session_id_len);
1.13 markus 1372: if ((session_id2 == NULL) ||
1373: (kex->session_id_len != session_id2_len) ||
1374: (memcmp(kex->session_id, session_id2, session_id2_len) != 0))
1375: fatal("mm_get_get: internal error: bad session id");
1.1 provos 1376: kex->we_need = buffer_get_int(m);
1.34 markus 1377: kex->kex[KEX_DH_GRP1_SHA1] = kexdh_server;
1.58 djm 1378: kex->kex[KEX_DH_GRP14_SHA1] = kexdh_server;
1.34 markus 1379: kex->kex[KEX_DH_GEX_SHA1] = kexgex_server;
1.1 provos 1380: kex->server = 1;
1381: kex->hostkey_type = buffer_get_int(m);
1382: kex->kex_type = buffer_get_int(m);
1383: blob = buffer_get_string(m, &bloblen);
1384: buffer_init(&kex->my);
1385: buffer_append(&kex->my, blob, bloblen);
1386: xfree(blob);
1387: blob = buffer_get_string(m, &bloblen);
1388: buffer_init(&kex->peer);
1389: buffer_append(&kex->peer, blob, bloblen);
1390: xfree(blob);
1391: kex->done = 1;
1392: kex->flags = buffer_get_int(m);
1393: kex->client_version_string = buffer_get_string(m, NULL);
1394: kex->server_version_string = buffer_get_string(m, NULL);
1395: kex->load_host_key=&get_hostkey_by_type;
1396: kex->host_key_index=&get_hostkey_index;
1397:
1398: return (kex);
1399: }
1400:
1401: /* This function requries careful sanity checking */
1402:
1403: void
1.11 mouring 1404: mm_get_keystate(struct monitor *pmonitor)
1.1 provos 1405: {
1406: Buffer m;
1407: u_char *blob, *p;
1408: u_int bloblen, plen;
1.37 markus 1409: u_int32_t seqnr, packets;
1410: u_int64_t blocks;
1.1 provos 1411:
1.14 markus 1412: debug3("%s: Waiting for new keys", __func__);
1.1 provos 1413:
1414: buffer_init(&m);
1.11 mouring 1415: mm_request_receive_expect(pmonitor->m_sendfd, MONITOR_REQ_KEYEXPORT, &m);
1.1 provos 1416: if (!compat20) {
1417: child_state.ssh1protoflags = buffer_get_int(&m);
1418: child_state.ssh1cipher = buffer_get_int(&m);
1.15 markus 1419: child_state.ssh1key = buffer_get_string(&m,
1420: &child_state.ssh1keylen);
1.1 provos 1421: child_state.ivout = buffer_get_string(&m,
1422: &child_state.ivoutlen);
1423: child_state.ivin = buffer_get_string(&m, &child_state.ivinlen);
1424: goto skip;
1425: } else {
1426: /* Get the Kex for rekeying */
1.11 mouring 1427: *pmonitor->m_pkex = mm_get_kex(&m);
1.1 provos 1428: }
1429:
1430: blob = buffer_get_string(&m, &bloblen);
1431: current_keys[MODE_OUT] = mm_newkeys_from_blob(blob, bloblen);
1432: xfree(blob);
1433:
1.14 markus 1434: debug3("%s: Waiting for second key", __func__);
1.1 provos 1435: blob = buffer_get_string(&m, &bloblen);
1436: current_keys[MODE_IN] = mm_newkeys_from_blob(blob, bloblen);
1437: xfree(blob);
1.3 markus 1438:
1.1 provos 1439: /* Now get sequence numbers for the packets */
1.37 markus 1440: seqnr = buffer_get_int(&m);
1441: blocks = buffer_get_int64(&m);
1442: packets = buffer_get_int(&m);
1443: packet_set_state(MODE_OUT, seqnr, blocks, packets);
1444: seqnr = buffer_get_int(&m);
1445: blocks = buffer_get_int64(&m);
1446: packets = buffer_get_int(&m);
1447: packet_set_state(MODE_IN, seqnr, blocks, packets);
1.1 provos 1448:
1449: skip:
1450: /* Get the key context */
1451: child_state.keyout = buffer_get_string(&m, &child_state.keyoutlen);
1452: child_state.keyin = buffer_get_string(&m, &child_state.keyinlen);
1453:
1.14 markus 1454: debug3("%s: Getting compression state", __func__);
1.1 provos 1455: /* Get compression state */
1456: p = buffer_get_string(&m, &plen);
1457: if (plen != sizeof(child_state.outgoing))
1.14 markus 1458: fatal("%s: bad request size", __func__);
1.1 provos 1459: memcpy(&child_state.outgoing, p, sizeof(child_state.outgoing));
1460: xfree(p);
1461:
1462: p = buffer_get_string(&m, &plen);
1463: if (plen != sizeof(child_state.incoming))
1.14 markus 1464: fatal("%s: bad request size", __func__);
1.1 provos 1465: memcpy(&child_state.incoming, p, sizeof(child_state.incoming));
1466: xfree(p);
1467:
1468: /* Network I/O buffers */
1.14 markus 1469: debug3("%s: Getting Network I/O buffers", __func__);
1.1 provos 1470: child_state.input = buffer_get_string(&m, &child_state.ilen);
1471: child_state.output = buffer_get_string(&m, &child_state.olen);
1472:
1473: buffer_free(&m);
1474: }
1475:
1476:
1477: /* Allocation functions for zlib */
1478: void *
1479: mm_zalloc(struct mm_master *mm, u_int ncount, u_int size)
1480: {
1.30 markus 1481: size_t len = (size_t) size * ncount;
1.1 provos 1482: void *address;
1483:
1.23 millert 1484: if (len == 0 || ncount > SIZE_T_MAX / size)
1.18 deraadt 1485: fatal("%s: mm_zalloc(%u, %u)", __func__, ncount, size);
1486:
1487: address = mm_malloc(mm, len);
1.1 provos 1488:
1489: return (address);
1490: }
1491:
1492: void
1493: mm_zfree(struct mm_master *mm, void *address)
1494: {
1495: mm_free(mm, address);
1496: }
1497:
1498: void
1499: mm_init_compression(struct mm_master *mm)
1500: {
1501: outgoing_stream.zalloc = (alloc_func)mm_zalloc;
1502: outgoing_stream.zfree = (free_func)mm_zfree;
1503: outgoing_stream.opaque = mm;
1504:
1505: incoming_stream.zalloc = (alloc_func)mm_zalloc;
1506: incoming_stream.zfree = (free_func)mm_zfree;
1507: incoming_stream.opaque = mm;
1508: }
1509:
1510: /* XXX */
1511:
1512: #define FD_CLOSEONEXEC(x) do { \
1513: if (fcntl(x, F_SETFD, 1) == -1) \
1514: fatal("fcntl(%d, F_SETFD)", x); \
1515: } while (0)
1516:
1.2 markus 1517: static void
1.1 provos 1518: monitor_socketpair(int *pair)
1.3 markus 1519: {
1.1 provos 1520: if (socketpair(AF_UNIX, SOCK_STREAM, 0, pair) == -1)
1.14 markus 1521: fatal("%s: socketpair", __func__);
1.1 provos 1522: FD_CLOSEONEXEC(pair[0]);
1523: FD_CLOSEONEXEC(pair[1]);
1524: }
1525:
1526: #define MM_MEMSIZE 65536
1527:
1528: struct monitor *
1529: monitor_init(void)
1530: {
1531: struct monitor *mon;
1532: int pair[2];
1533:
1534: mon = xmalloc(sizeof(*mon));
1535:
1.55 dtucker 1536: mon->m_pid = 0;
1.1 provos 1537: monitor_socketpair(pair);
1538:
1539: mon->m_recvfd = pair[0];
1540: mon->m_sendfd = pair[1];
1541:
1542: /* Used to share zlib space across processes */
1.16 djm 1543: if (options.compression) {
1544: mon->m_zback = mm_create(NULL, MM_MEMSIZE);
1545: mon->m_zlib = mm_create(mon->m_zback, 20 * MM_MEMSIZE);
1.1 provos 1546:
1.16 djm 1547: /* Compression needs to share state across borders */
1548: mm_init_compression(mon->m_zlib);
1549: }
1.1 provos 1550:
1551: return mon;
1552: }
1553:
1554: void
1555: monitor_reinit(struct monitor *mon)
1556: {
1557: int pair[2];
1558:
1559: monitor_socketpair(pair);
1560:
1561: mon->m_recvfd = pair[0];
1562: mon->m_sendfd = pair[1];
1563: }
1.46 markus 1564:
1565: #ifdef GSSAPI
1566: int
1.59 avsm 1567: mm_answer_gss_setup_ctx(int sock, Buffer *m)
1.46 markus 1568: {
1.59 avsm 1569: gss_OID_desc goid;
1.46 markus 1570: OM_uint32 major;
1571: u_int len;
1572:
1.59 avsm 1573: goid.elements = buffer_get_string(m, &len);
1574: goid.length = len;
1.46 markus 1575:
1.59 avsm 1576: major = ssh_gssapi_server_ctx(&gsscontext, &goid);
1.46 markus 1577:
1.59 avsm 1578: xfree(goid.elements);
1.46 markus 1579:
1580: buffer_clear(m);
1581: buffer_put_int(m, major);
1582:
1.64 stevesk 1583: mm_request_send(sock, MONITOR_ANS_GSSSETUP, m);
1.46 markus 1584:
1585: /* Now we have a context, enable the step */
1586: monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 1);
1587:
1588: return (0);
1589: }
1590:
1591: int
1.59 avsm 1592: mm_answer_gss_accept_ctx(int sock, Buffer *m)
1.46 markus 1593: {
1594: gss_buffer_desc in;
1595: gss_buffer_desc out = GSS_C_EMPTY_BUFFER;
1.64 stevesk 1596: OM_uint32 major, minor;
1.46 markus 1597: OM_uint32 flags = 0; /* GSI needs this */
1.47 deraadt 1598: u_int len;
1.46 markus 1599:
1.47 deraadt 1600: in.value = buffer_get_string(m, &len);
1601: in.length = len;
1.46 markus 1602: major = ssh_gssapi_accept_ctx(gsscontext, &in, &out, &flags);
1603: xfree(in.value);
1604:
1605: buffer_clear(m);
1606: buffer_put_int(m, major);
1607: buffer_put_string(m, out.value, out.length);
1608: buffer_put_int(m, flags);
1.59 avsm 1609: mm_request_send(sock, MONITOR_ANS_GSSSTEP, m);
1.46 markus 1610:
1611: gss_release_buffer(&minor, &out);
1612:
1.64 stevesk 1613: if (major == GSS_S_COMPLETE) {
1.46 markus 1614: monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 0);
1615: monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
1.52 markus 1616: monitor_permit(mon_dispatch, MONITOR_REQ_GSSCHECKMIC, 1);
1.46 markus 1617: }
1618: return (0);
1619: }
1620:
1621: int
1.59 avsm 1622: mm_answer_gss_checkmic(int sock, Buffer *m)
1.52 markus 1623: {
1624: gss_buffer_desc gssbuf, mic;
1625: OM_uint32 ret;
1626: u_int len;
1.54 djm 1627:
1.52 markus 1628: gssbuf.value = buffer_get_string(m, &len);
1629: gssbuf.length = len;
1630: mic.value = buffer_get_string(m, &len);
1631: mic.length = len;
1.54 djm 1632:
1.52 markus 1633: ret = ssh_gssapi_checkmic(gsscontext, &gssbuf, &mic);
1.54 djm 1634:
1.52 markus 1635: xfree(gssbuf.value);
1636: xfree(mic.value);
1.54 djm 1637:
1.52 markus 1638: buffer_clear(m);
1639: buffer_put_int(m, ret);
1.54 djm 1640:
1.59 avsm 1641: mm_request_send(sock, MONITOR_ANS_GSSCHECKMIC, m);
1.54 djm 1642:
1.52 markus 1643: if (!GSS_ERROR(ret))
1644: monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
1.54 djm 1645:
1.52 markus 1646: return (0);
1647: }
1648:
1649: int
1.59 avsm 1650: mm_answer_gss_userok(int sock, Buffer *m)
1.46 markus 1651: {
1652: int authenticated;
1653:
1654: authenticated = authctxt->valid && ssh_gssapi_userok(authctxt->user);
1655:
1656: buffer_clear(m);
1657: buffer_put_int(m, authenticated);
1658:
1659: debug3("%s: sending result %d", __func__, authenticated);
1.59 avsm 1660: mm_request_send(sock, MONITOR_ANS_GSSUSEROK, m);
1.46 markus 1661:
1.64 stevesk 1662: auth_method = "gssapi-with-mic";
1.46 markus 1663:
1664: /* Monitor loop will terminate if authenticated */
1665: return (authenticated);
1666: }
1667: #endif /* GSSAPI */
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