Annotation of src/usr.bin/ssh/monitor.c, Revision 1.80
1.80 ! stevesk 1: /* $OpenBSD: monitor.c,v 1.79 2006/07/08 21:48:53 stevesk Exp $ */
1.1 provos 2: /*
3: * Copyright 2002 Niels Provos <provos@citi.umich.edu>
4: * Copyright 2002 Markus Friedl <markus@openbsd.org>
5: * All rights reserved.
6: *
7: * Redistribution and use in source and binary forms, with or without
8: * modification, are permitted provided that the following conditions
9: * are met:
10: * 1. Redistributions of source code must retain the above copyright
11: * notice, this list of conditions and the following disclaimer.
12: * 2. Redistributions in binary form must reproduce the above copyright
13: * notice, this list of conditions and the following disclaimer in the
14: * documentation and/or other materials provided with the distribution.
15: *
16: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26: */
27:
28: #include "includes.h"
1.67 stevesk 29:
30: #include <sys/types.h>
31: #include <sys/wait.h>
1.79 stevesk 32: #include <sys/socket.h>
1.1 provos 33:
1.78 stevesk 34: #include <openssl/dh.h>
35:
1.80 ! stevesk 36: #include <fcntl.h>
1.65 stevesk 37: #include <paths.h>
1.78 stevesk 38: #include <pwd.h>
1.68 stevesk 39: #include <signal.h>
1.1 provos 40:
41: #ifdef SKEY
42: #include <skey.h>
43: #endif
44:
45: #include "ssh.h"
46: #include "auth.h"
47: #include "kex.h"
48: #include "dh.h"
49: #include "zlib.h"
50: #include "packet.h"
51: #include "auth-options.h"
52: #include "sshpty.h"
53: #include "channels.h"
54: #include "session.h"
55: #include "sshlogin.h"
56: #include "canohost.h"
57: #include "log.h"
58: #include "servconf.h"
59: #include "monitor.h"
60: #include "monitor_mm.h"
61: #include "monitor_wrap.h"
62: #include "monitor_fdpass.h"
63: #include "xmalloc.h"
64: #include "misc.h"
65: #include "buffer.h"
66: #include "bufaux.h"
67: #include "compat.h"
68: #include "ssh2.h"
69:
1.46 markus 70: #ifdef GSSAPI
71: #include "ssh-gss.h"
72: static Gssctxt *gsscontext = NULL;
73: #endif
74:
1.1 provos 75: /* Imports */
76: extern ServerOptions options;
77: extern u_int utmp_len;
78: extern Newkeys *current_keys[];
79: extern z_stream incoming_stream;
80: extern z_stream outgoing_stream;
81: extern u_char session_id[];
82: extern Buffer input, output;
83: extern Buffer auth_debug;
84: extern int auth_debug_init;
1.61 dtucker 85: extern Buffer loginmsg;
1.1 provos 86:
87: /* State exported from the child */
88:
89: struct {
90: z_stream incoming;
91: z_stream outgoing;
92: u_char *keyin;
93: u_int keyinlen;
94: u_char *keyout;
95: u_int keyoutlen;
96: u_char *ivin;
97: u_int ivinlen;
98: u_char *ivout;
99: u_int ivoutlen;
1.15 markus 100: u_char *ssh1key;
101: u_int ssh1keylen;
1.1 provos 102: int ssh1cipher;
103: int ssh1protoflags;
104: u_char *input;
105: u_int ilen;
106: u_char *output;
107: u_int olen;
108: } child_state;
109:
1.43 markus 110: /* Functions on the monitor that answer unprivileged requests */
1.1 provos 111:
112: int mm_answer_moduli(int, Buffer *);
113: int mm_answer_sign(int, Buffer *);
114: int mm_answer_pwnamallow(int, Buffer *);
1.10 djm 115: int mm_answer_auth2_read_banner(int, Buffer *);
1.1 provos 116: int mm_answer_authserv(int, Buffer *);
117: int mm_answer_authpassword(int, Buffer *);
118: int mm_answer_bsdauthquery(int, Buffer *);
119: int mm_answer_bsdauthrespond(int, Buffer *);
120: int mm_answer_skeyquery(int, Buffer *);
121: int mm_answer_skeyrespond(int, Buffer *);
122: int mm_answer_keyallowed(int, Buffer *);
123: int mm_answer_keyverify(int, Buffer *);
124: int mm_answer_pty(int, Buffer *);
125: int mm_answer_pty_cleanup(int, Buffer *);
126: int mm_answer_term(int, Buffer *);
127: int mm_answer_rsa_keyallowed(int, Buffer *);
128: int mm_answer_rsa_challenge(int, Buffer *);
129: int mm_answer_rsa_response(int, Buffer *);
130: int mm_answer_sesskey(int, Buffer *);
131: int mm_answer_sessid(int, Buffer *);
132:
1.46 markus 133: #ifdef GSSAPI
134: int mm_answer_gss_setup_ctx(int, Buffer *);
135: int mm_answer_gss_accept_ctx(int, Buffer *);
136: int mm_answer_gss_userok(int, Buffer *);
1.52 markus 137: int mm_answer_gss_checkmic(int, Buffer *);
1.46 markus 138: #endif
1.25 itojun 139:
1.1 provos 140: static Authctxt *authctxt;
141: static BIGNUM *ssh1_challenge = NULL; /* used for ssh1 rsa auth */
142:
143: /* local state for key verify */
144: static u_char *key_blob = NULL;
145: static u_int key_bloblen = 0;
146: static int key_blobtype = MM_NOKEY;
1.26 markus 147: static char *hostbased_cuser = NULL;
148: static char *hostbased_chost = NULL;
1.1 provos 149: static char *auth_method = "unknown";
1.44 markus 150: static u_int session_id2_len = 0;
1.13 markus 151: static u_char *session_id2 = NULL;
1.40 markus 152: static pid_t monitor_child_pid;
1.1 provos 153:
154: struct mon_table {
155: enum monitor_reqtype type;
156: int flags;
157: int (*f)(int, Buffer *);
158: };
159:
160: #define MON_ISAUTH 0x0004 /* Required for Authentication */
161: #define MON_AUTHDECIDE 0x0008 /* Decides Authentication */
162: #define MON_ONCE 0x0010 /* Disable after calling */
1.77 dtucker 163: #define MON_ALOG 0x0020 /* Log auth attempt without authenticating */
1.1 provos 164:
165: #define MON_AUTH (MON_ISAUTH|MON_AUTHDECIDE)
166:
167: #define MON_PERMIT 0x1000 /* Request is permitted */
168:
169: struct mon_table mon_dispatch_proto20[] = {
170: {MONITOR_REQ_MODULI, MON_ONCE, mm_answer_moduli},
171: {MONITOR_REQ_SIGN, MON_ONCE, mm_answer_sign},
172: {MONITOR_REQ_PWNAM, MON_ONCE, mm_answer_pwnamallow},
173: {MONITOR_REQ_AUTHSERV, MON_ONCE, mm_answer_authserv},
1.10 djm 174: {MONITOR_REQ_AUTH2_READ_BANNER, MON_ONCE, mm_answer_auth2_read_banner},
1.1 provos 175: {MONITOR_REQ_AUTHPASSWORD, MON_AUTH, mm_answer_authpassword},
176: #ifdef BSD_AUTH
177: {MONITOR_REQ_BSDAUTHQUERY, MON_ISAUTH, mm_answer_bsdauthquery},
1.66 stevesk 178: {MONITOR_REQ_BSDAUTHRESPOND, MON_AUTH, mm_answer_bsdauthrespond},
1.1 provos 179: #endif
180: #ifdef SKEY
181: {MONITOR_REQ_SKEYQUERY, MON_ISAUTH, mm_answer_skeyquery},
182: {MONITOR_REQ_SKEYRESPOND, MON_AUTH, mm_answer_skeyrespond},
183: #endif
184: {MONITOR_REQ_KEYALLOWED, MON_ISAUTH, mm_answer_keyallowed},
185: {MONITOR_REQ_KEYVERIFY, MON_AUTH, mm_answer_keyverify},
1.46 markus 186: #ifdef GSSAPI
187: {MONITOR_REQ_GSSSETUP, MON_ISAUTH, mm_answer_gss_setup_ctx},
188: {MONITOR_REQ_GSSSTEP, MON_ISAUTH, mm_answer_gss_accept_ctx},
189: {MONITOR_REQ_GSSUSEROK, MON_AUTH, mm_answer_gss_userok},
1.52 markus 190: {MONITOR_REQ_GSSCHECKMIC, MON_ISAUTH, mm_answer_gss_checkmic},
1.46 markus 191: #endif
1.1 provos 192: {0, 0, NULL}
193: };
194:
195: struct mon_table mon_dispatch_postauth20[] = {
196: {MONITOR_REQ_MODULI, 0, mm_answer_moduli},
197: {MONITOR_REQ_SIGN, 0, mm_answer_sign},
198: {MONITOR_REQ_PTY, 0, mm_answer_pty},
199: {MONITOR_REQ_PTYCLEANUP, 0, mm_answer_pty_cleanup},
200: {MONITOR_REQ_TERM, 0, mm_answer_term},
201: {0, 0, NULL}
202: };
203:
204: struct mon_table mon_dispatch_proto15[] = {
205: {MONITOR_REQ_PWNAM, MON_ONCE, mm_answer_pwnamallow},
206: {MONITOR_REQ_SESSKEY, MON_ONCE, mm_answer_sesskey},
207: {MONITOR_REQ_SESSID, MON_ONCE, mm_answer_sessid},
208: {MONITOR_REQ_AUTHPASSWORD, MON_AUTH, mm_answer_authpassword},
1.77 dtucker 209: {MONITOR_REQ_RSAKEYALLOWED, MON_ISAUTH|MON_ALOG, mm_answer_rsa_keyallowed},
210: {MONITOR_REQ_KEYALLOWED, MON_ISAUTH|MON_ALOG, mm_answer_keyallowed},
1.1 provos 211: {MONITOR_REQ_RSACHALLENGE, MON_ONCE, mm_answer_rsa_challenge},
212: {MONITOR_REQ_RSARESPONSE, MON_ONCE|MON_AUTHDECIDE, mm_answer_rsa_response},
213: #ifdef BSD_AUTH
214: {MONITOR_REQ_BSDAUTHQUERY, MON_ISAUTH, mm_answer_bsdauthquery},
1.66 stevesk 215: {MONITOR_REQ_BSDAUTHRESPOND, MON_AUTH, mm_answer_bsdauthrespond},
1.1 provos 216: #endif
217: #ifdef SKEY
218: {MONITOR_REQ_SKEYQUERY, MON_ISAUTH, mm_answer_skeyquery},
219: {MONITOR_REQ_SKEYRESPOND, MON_AUTH, mm_answer_skeyrespond},
220: #endif
221: {0, 0, NULL}
222: };
223:
224: struct mon_table mon_dispatch_postauth15[] = {
225: {MONITOR_REQ_PTY, MON_ONCE, mm_answer_pty},
226: {MONITOR_REQ_PTYCLEANUP, MON_ONCE, mm_answer_pty_cleanup},
227: {MONITOR_REQ_TERM, 0, mm_answer_term},
228: {0, 0, NULL}
229: };
230:
231: struct mon_table *mon_dispatch;
232:
233: /* Specifies if a certain message is allowed at the moment */
234:
235: static void
236: monitor_permit(struct mon_table *ent, enum monitor_reqtype type, int permit)
237: {
238: while (ent->f != NULL) {
239: if (ent->type == type) {
240: ent->flags &= ~MON_PERMIT;
241: ent->flags |= permit ? MON_PERMIT : 0;
242: return;
243: }
244: ent++;
245: }
246: }
247:
248: static void
249: monitor_permit_authentications(int permit)
250: {
251: struct mon_table *ent = mon_dispatch;
252:
253: while (ent->f != NULL) {
254: if (ent->flags & MON_AUTH) {
255: ent->flags &= ~MON_PERMIT;
256: ent->flags |= permit ? MON_PERMIT : 0;
257: }
258: ent++;
259: }
260: }
261:
1.50 markus 262: void
263: monitor_child_preauth(Authctxt *_authctxt, struct monitor *pmonitor)
1.1 provos 264: {
265: struct mon_table *ent;
266: int authenticated = 0;
267:
268: debug3("preauth child monitor started");
269:
1.50 markus 270: authctxt = _authctxt;
271: memset(authctxt, 0, sizeof(*authctxt));
272:
1.1 provos 273: if (compat20) {
274: mon_dispatch = mon_dispatch_proto20;
275:
276: /* Permit requests for moduli and signatures */
277: monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
278: monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
279: } else {
280: mon_dispatch = mon_dispatch_proto15;
281:
282: monitor_permit(mon_dispatch, MONITOR_REQ_SESSKEY, 1);
283: }
284:
285: /* The first few requests do not require asynchronous access */
286: while (!authenticated) {
1.77 dtucker 287: auth_method = "unknown";
1.11 mouring 288: authenticated = monitor_read(pmonitor, mon_dispatch, &ent);
1.1 provos 289: if (authenticated) {
290: if (!(ent->flags & MON_AUTHDECIDE))
291: fatal("%s: unexpected authentication from %d",
1.14 markus 292: __func__, ent->type);
1.1 provos 293: if (authctxt->pw->pw_uid == 0 &&
294: !auth_root_allowed(auth_method))
295: authenticated = 0;
296: }
297:
1.77 dtucker 298: if (ent->flags & (MON_AUTHDECIDE|MON_ALOG)) {
1.1 provos 299: auth_log(authctxt, authenticated, auth_method,
300: compat20 ? " ssh2" : "");
301: if (!authenticated)
302: authctxt->failures++;
303: }
304: }
305:
306: if (!authctxt->valid)
1.14 markus 307: fatal("%s: authenticated invalid user", __func__);
1.77 dtucker 308: if (strcmp(auth_method, "unknown") == 0)
309: fatal("%s: authentication method name unknown", __func__);
1.1 provos 310:
311: debug("%s: %s has been authenticated by privileged process",
1.14 markus 312: __func__, authctxt->user);
1.1 provos 313:
1.11 mouring 314: mm_get_keystate(pmonitor);
1.1 provos 315: }
316:
1.40 markus 317: static void
318: monitor_set_child_handler(pid_t pid)
319: {
320: monitor_child_pid = pid;
321: }
322:
323: static void
1.59 avsm 324: monitor_child_handler(int sig)
1.40 markus 325: {
1.59 avsm 326: kill(monitor_child_pid, sig);
1.40 markus 327: }
328:
1.1 provos 329: void
1.11 mouring 330: monitor_child_postauth(struct monitor *pmonitor)
1.1 provos 331: {
1.40 markus 332: monitor_set_child_handler(pmonitor->m_pid);
333: signal(SIGHUP, &monitor_child_handler);
334: signal(SIGTERM, &monitor_child_handler);
335:
1.1 provos 336: if (compat20) {
337: mon_dispatch = mon_dispatch_postauth20;
338:
339: /* Permit requests for moduli and signatures */
340: monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
341: monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
342: monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1);
343: } else {
344: mon_dispatch = mon_dispatch_postauth15;
345: monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1);
346: }
347: if (!no_pty_flag) {
348: monitor_permit(mon_dispatch, MONITOR_REQ_PTY, 1);
349: monitor_permit(mon_dispatch, MONITOR_REQ_PTYCLEANUP, 1);
350: }
351:
352: for (;;)
1.11 mouring 353: monitor_read(pmonitor, mon_dispatch, NULL);
1.1 provos 354: }
355:
356: void
1.11 mouring 357: monitor_sync(struct monitor *pmonitor)
1.1 provos 358: {
1.16 djm 359: if (options.compression) {
360: /* The member allocation is not visible, so sync it */
361: mm_share_sync(&pmonitor->m_zlib, &pmonitor->m_zback);
362: }
1.1 provos 363: }
364:
365: int
1.11 mouring 366: monitor_read(struct monitor *pmonitor, struct mon_table *ent,
1.1 provos 367: struct mon_table **pent)
368: {
369: Buffer m;
370: int ret;
371: u_char type;
372:
373: buffer_init(&m);
374:
1.11 mouring 375: mm_request_receive(pmonitor->m_sendfd, &m);
1.1 provos 376: type = buffer_get_char(&m);
377:
1.14 markus 378: debug3("%s: checking request %d", __func__, type);
1.1 provos 379:
380: while (ent->f != NULL) {
381: if (ent->type == type)
382: break;
383: ent++;
384: }
385:
386: if (ent->f != NULL) {
387: if (!(ent->flags & MON_PERMIT))
1.14 markus 388: fatal("%s: unpermitted request %d", __func__,
1.1 provos 389: type);
1.11 mouring 390: ret = (*ent->f)(pmonitor->m_sendfd, &m);
1.1 provos 391: buffer_free(&m);
392:
393: /* The child may use this request only once, disable it */
394: if (ent->flags & MON_ONCE) {
1.14 markus 395: debug2("%s: %d used once, disabling now", __func__,
1.1 provos 396: type);
397: ent->flags &= ~MON_PERMIT;
398: }
399:
400: if (pent != NULL)
401: *pent = ent;
1.3 markus 402:
1.1 provos 403: return ret;
404: }
405:
1.14 markus 406: fatal("%s: unsupported request: %d", __func__, type);
1.1 provos 407:
408: /* NOTREACHED */
409: return (-1);
410: }
411:
412: /* allowed key state */
413: static int
414: monitor_allowed_key(u_char *blob, u_int bloblen)
415: {
416: /* make sure key is allowed */
417: if (key_blob == NULL || key_bloblen != bloblen ||
418: memcmp(key_blob, blob, key_bloblen))
419: return (0);
420: return (1);
421: }
422:
423: static void
424: monitor_reset_key_state(void)
425: {
426: /* reset state */
427: if (key_blob != NULL)
428: xfree(key_blob);
429: if (hostbased_cuser != NULL)
430: xfree(hostbased_cuser);
431: if (hostbased_chost != NULL)
432: xfree(hostbased_chost);
433: key_blob = NULL;
434: key_bloblen = 0;
435: key_blobtype = MM_NOKEY;
436: hostbased_cuser = NULL;
437: hostbased_chost = NULL;
438: }
439:
440: int
1.59 avsm 441: mm_answer_moduli(int sock, Buffer *m)
1.1 provos 442: {
443: DH *dh;
444: int min, want, max;
445:
446: min = buffer_get_int(m);
447: want = buffer_get_int(m);
448: max = buffer_get_int(m);
449:
450: debug3("%s: got parameters: %d %d %d",
1.14 markus 451: __func__, min, want, max);
1.1 provos 452: /* We need to check here, too, in case the child got corrupted */
453: if (max < min || want < min || max < want)
454: fatal("%s: bad parameters: %d %d %d",
1.14 markus 455: __func__, min, want, max);
1.1 provos 456:
457: buffer_clear(m);
458:
459: dh = choose_dh(min, want, max);
460: if (dh == NULL) {
461: buffer_put_char(m, 0);
462: return (0);
463: } else {
464: /* Send first bignum */
465: buffer_put_char(m, 1);
466: buffer_put_bignum2(m, dh->p);
467: buffer_put_bignum2(m, dh->g);
1.3 markus 468:
1.1 provos 469: DH_free(dh);
470: }
1.59 avsm 471: mm_request_send(sock, MONITOR_ANS_MODULI, m);
1.1 provos 472: return (0);
473: }
474:
475: int
1.59 avsm 476: mm_answer_sign(int sock, Buffer *m)
1.1 provos 477: {
478: Key *key;
479: u_char *p;
480: u_char *signature;
481: u_int siglen, datlen;
482: int keyid;
1.3 markus 483:
1.14 markus 484: debug3("%s", __func__);
1.1 provos 485:
1.3 markus 486: keyid = buffer_get_int(m);
487: p = buffer_get_string(m, &datlen);
1.1 provos 488:
1.69 djm 489: /*
1.71 deraadt 490: * Supported KEX types will only return SHA1 (20 byte) or
1.69 djm 491: * SHA256 (32 byte) hashes
492: */
493: if (datlen != 20 && datlen != 32)
1.19 deraadt 494: fatal("%s: data length incorrect: %u", __func__, datlen);
1.1 provos 495:
1.13 markus 496: /* save session id, it will be passed on the first call */
497: if (session_id2_len == 0) {
498: session_id2_len = datlen;
499: session_id2 = xmalloc(session_id2_len);
500: memcpy(session_id2, p, session_id2_len);
501: }
502:
1.1 provos 503: if ((key = get_hostkey_by_index(keyid)) == NULL)
1.14 markus 504: fatal("%s: no hostkey from index %d", __func__, keyid);
1.1 provos 505: if (key_sign(key, &signature, &siglen, p, datlen) < 0)
1.14 markus 506: fatal("%s: key_sign failed", __func__);
1.1 provos 507:
1.19 deraadt 508: debug3("%s: signature %p(%u)", __func__, signature, siglen);
1.1 provos 509:
510: buffer_clear(m);
511: buffer_put_string(m, signature, siglen);
512:
513: xfree(p);
514: xfree(signature);
515:
1.59 avsm 516: mm_request_send(sock, MONITOR_ANS_SIGN, m);
1.1 provos 517:
518: /* Turn on permissions for getpwnam */
519: monitor_permit(mon_dispatch, MONITOR_REQ_PWNAM, 1);
520:
521: return (0);
522: }
523:
524: /* Retrieves the password entry and also checks if the user is permitted */
525:
526: int
1.59 avsm 527: mm_answer_pwnamallow(int sock, Buffer *m)
1.1 provos 528: {
1.60 dtucker 529: char *username;
1.1 provos 530: struct passwd *pwent;
531: int allowed = 0;
1.3 markus 532:
1.14 markus 533: debug3("%s", __func__);
1.1 provos 534:
535: if (authctxt->attempt++ != 0)
1.14 markus 536: fatal("%s: multiple attempts for getpwnam", __func__);
1.1 provos 537:
1.60 dtucker 538: username = buffer_get_string(m, NULL);
1.1 provos 539:
1.60 dtucker 540: pwent = getpwnamallow(username);
1.1 provos 541:
1.60 dtucker 542: authctxt->user = xstrdup(username);
543: setproctitle("%s [priv]", pwent ? username : "unknown");
544: xfree(username);
1.1 provos 545:
546: buffer_clear(m);
547:
548: if (pwent == NULL) {
549: buffer_put_char(m, 0);
1.53 djm 550: authctxt->pw = fakepw();
1.1 provos 551: goto out;
552: }
553:
554: allowed = 1;
1.4 markus 555: authctxt->pw = pwent;
1.1 provos 556: authctxt->valid = 1;
557:
558: buffer_put_char(m, 1);
559: buffer_put_string(m, pwent, sizeof(struct passwd));
560: buffer_put_cstring(m, pwent->pw_name);
561: buffer_put_cstring(m, "*");
562: buffer_put_cstring(m, pwent->pw_gecos);
563: buffer_put_cstring(m, pwent->pw_class);
564: buffer_put_cstring(m, pwent->pw_dir);
565: buffer_put_cstring(m, pwent->pw_shell);
566:
567: out:
1.14 markus 568: debug3("%s: sending MONITOR_ANS_PWNAM: %d", __func__, allowed);
1.59 avsm 569: mm_request_send(sock, MONITOR_ANS_PWNAM, m);
1.1 provos 570:
571: /* For SSHv1 allow authentication now */
572: if (!compat20)
573: monitor_permit_authentications(1);
1.10 djm 574: else {
1.1 provos 575: /* Allow service/style information on the auth context */
576: monitor_permit(mon_dispatch, MONITOR_REQ_AUTHSERV, 1);
1.10 djm 577: monitor_permit(mon_dispatch, MONITOR_REQ_AUTH2_READ_BANNER, 1);
578: }
579:
580:
581: return (0);
582: }
583:
1.59 avsm 584: int mm_answer_auth2_read_banner(int sock, Buffer *m)
1.10 djm 585: {
586: char *banner;
587:
588: buffer_clear(m);
589: banner = auth2_read_banner();
590: buffer_put_cstring(m, banner != NULL ? banner : "");
1.59 avsm 591: mm_request_send(sock, MONITOR_ANS_AUTH2_READ_BANNER, m);
1.1 provos 592:
1.10 djm 593: if (banner != NULL)
1.21 deraadt 594: xfree(banner);
1.1 provos 595:
596: return (0);
597: }
598:
599: int
1.59 avsm 600: mm_answer_authserv(int sock, Buffer *m)
1.1 provos 601: {
602: monitor_permit_authentications(1);
603:
604: authctxt->service = buffer_get_string(m, NULL);
605: authctxt->style = buffer_get_string(m, NULL);
1.6 stevesk 606: debug3("%s: service=%s, style=%s",
1.14 markus 607: __func__, authctxt->service, authctxt->style);
1.6 stevesk 608:
1.1 provos 609: if (strlen(authctxt->style) == 0) {
610: xfree(authctxt->style);
611: authctxt->style = NULL;
612: }
613:
614: return (0);
615: }
616:
617: int
1.59 avsm 618: mm_answer_authpassword(int sock, Buffer *m)
1.1 provos 619: {
620: static int call_count;
621: char *passwd;
1.22 stevesk 622: int authenticated;
623: u_int plen;
1.1 provos 624:
625: passwd = buffer_get_string(m, &plen);
626: /* Only authenticate if the context is valid */
1.12 markus 627: authenticated = options.password_authentication &&
1.48 markus 628: auth_password(authctxt, passwd);
1.1 provos 629: memset(passwd, 0, strlen(passwd));
630: xfree(passwd);
631:
632: buffer_clear(m);
633: buffer_put_int(m, authenticated);
634:
1.14 markus 635: debug3("%s: sending result %d", __func__, authenticated);
1.59 avsm 636: mm_request_send(sock, MONITOR_ANS_AUTHPASSWORD, m);
1.1 provos 637:
638: call_count++;
639: if (plen == 0 && call_count == 1)
640: auth_method = "none";
641: else
642: auth_method = "password";
643:
644: /* Causes monitor loop to terminate if authenticated */
645: return (authenticated);
646: }
647:
648: #ifdef BSD_AUTH
649: int
1.59 avsm 650: mm_answer_bsdauthquery(int sock, Buffer *m)
1.1 provos 651: {
652: char *name, *infotxt;
653: u_int numprompts;
654: u_int *echo_on;
655: char **prompts;
1.31 markus 656: u_int success;
1.1 provos 657:
1.31 markus 658: success = bsdauth_query(authctxt, &name, &infotxt, &numprompts,
659: &prompts, &echo_on) < 0 ? 0 : 1;
1.1 provos 660:
661: buffer_clear(m);
1.31 markus 662: buffer_put_int(m, success);
663: if (success)
1.1 provos 664: buffer_put_cstring(m, prompts[0]);
665:
1.31 markus 666: debug3("%s: sending challenge success: %u", __func__, success);
1.59 avsm 667: mm_request_send(sock, MONITOR_ANS_BSDAUTHQUERY, m);
1.1 provos 668:
1.31 markus 669: if (success) {
1.1 provos 670: xfree(name);
671: xfree(infotxt);
672: xfree(prompts);
673: xfree(echo_on);
674: }
675:
676: return (0);
677: }
678:
679: int
1.59 avsm 680: mm_answer_bsdauthrespond(int sock, Buffer *m)
1.1 provos 681: {
682: char *response;
683: int authok;
684:
685: if (authctxt->as == 0)
1.14 markus 686: fatal("%s: no bsd auth session", __func__);
1.1 provos 687:
688: response = buffer_get_string(m, NULL);
1.12 markus 689: authok = options.challenge_response_authentication &&
690: auth_userresponse(authctxt->as, response, 0);
1.1 provos 691: authctxt->as = NULL;
1.14 markus 692: debug3("%s: <%s> = <%d>", __func__, response, authok);
1.1 provos 693: xfree(response);
694:
695: buffer_clear(m);
696: buffer_put_int(m, authok);
697:
1.14 markus 698: debug3("%s: sending authenticated: %d", __func__, authok);
1.59 avsm 699: mm_request_send(sock, MONITOR_ANS_BSDAUTHRESPOND, m);
1.1 provos 700:
701: auth_method = "bsdauth";
702:
703: return (authok != 0);
704: }
705: #endif
706:
707: #ifdef SKEY
708: int
1.59 avsm 709: mm_answer_skeyquery(int sock, Buffer *m)
1.1 provos 710: {
711: struct skey skey;
712: char challenge[1024];
1.31 markus 713: u_int success;
1.1 provos 714:
1.31 markus 715: success = skeychallenge(&skey, authctxt->user, challenge) < 0 ? 0 : 1;
1.1 provos 716:
717: buffer_clear(m);
1.31 markus 718: buffer_put_int(m, success);
719: if (success)
1.1 provos 720: buffer_put_cstring(m, challenge);
721:
1.31 markus 722: debug3("%s: sending challenge success: %u", __func__, success);
1.59 avsm 723: mm_request_send(sock, MONITOR_ANS_SKEYQUERY, m);
1.1 provos 724:
725: return (0);
726: }
727:
728: int
1.59 avsm 729: mm_answer_skeyrespond(int sock, Buffer *m)
1.1 provos 730: {
731: char *response;
732: int authok;
733:
734: response = buffer_get_string(m, NULL);
735:
1.12 markus 736: authok = (options.challenge_response_authentication &&
737: authctxt->valid &&
1.1 provos 738: skey_haskey(authctxt->pw->pw_name) == 0 &&
739: skey_passcheck(authctxt->pw->pw_name, response) != -1);
740:
741: xfree(response);
742:
743: buffer_clear(m);
744: buffer_put_int(m, authok);
745:
1.14 markus 746: debug3("%s: sending authenticated: %d", __func__, authok);
1.59 avsm 747: mm_request_send(sock, MONITOR_ANS_SKEYRESPOND, m);
1.1 provos 748:
749: auth_method = "skey";
750:
751: return (authok != 0);
752: }
753: #endif
754:
1.2 markus 755: static void
1.1 provos 756: mm_append_debug(Buffer *m)
757: {
758: if (auth_debug_init && buffer_len(&auth_debug)) {
1.14 markus 759: debug3("%s: Appending debug messages for child", __func__);
1.1 provos 760: buffer_append(m, buffer_ptr(&auth_debug),
761: buffer_len(&auth_debug));
762: buffer_clear(&auth_debug);
763: }
764: }
765:
766: int
1.59 avsm 767: mm_answer_keyallowed(int sock, Buffer *m)
1.1 provos 768: {
769: Key *key;
1.26 markus 770: char *cuser, *chost;
771: u_char *blob;
1.1 provos 772: u_int bloblen;
773: enum mm_keytype type = 0;
774: int allowed = 0;
775:
1.14 markus 776: debug3("%s entering", __func__);
1.3 markus 777:
1.1 provos 778: type = buffer_get_int(m);
779: cuser = buffer_get_string(m, NULL);
780: chost = buffer_get_string(m, NULL);
781: blob = buffer_get_string(m, &bloblen);
782:
783: key = key_from_blob(blob, bloblen);
784:
785: if ((compat20 && type == MM_RSAHOSTKEY) ||
786: (!compat20 && type != MM_RSAHOSTKEY))
1.14 markus 787: fatal("%s: key type and protocol mismatch", __func__);
1.1 provos 788:
1.14 markus 789: debug3("%s: key_from_blob: %p", __func__, key);
1.1 provos 790:
1.51 djm 791: if (key != NULL && authctxt->valid) {
1.63 deraadt 792: switch (type) {
1.1 provos 793: case MM_USERKEY:
1.12 markus 794: allowed = options.pubkey_authentication &&
795: user_key_allowed(authctxt->pw, key);
1.77 dtucker 796: auth_method = "publickey";
1.1 provos 797: break;
798: case MM_HOSTKEY:
1.12 markus 799: allowed = options.hostbased_authentication &&
800: hostbased_key_allowed(authctxt->pw,
1.1 provos 801: cuser, chost, key);
1.77 dtucker 802: auth_method = "hostbased";
1.1 provos 803: break;
804: case MM_RSAHOSTKEY:
805: key->type = KEY_RSA1; /* XXX */
1.12 markus 806: allowed = options.rhosts_rsa_authentication &&
807: auth_rhosts_rsa_key_allowed(authctxt->pw,
1.1 provos 808: cuser, chost, key);
1.77 dtucker 809: auth_method = "rsa";
1.1 provos 810: break;
811: default:
1.14 markus 812: fatal("%s: unknown key type %d", __func__, type);
1.1 provos 813: break;
814: }
1.33 markus 815: }
816: if (key != NULL)
1.1 provos 817: key_free(key);
818:
819: /* clear temporarily storage (used by verify) */
820: monitor_reset_key_state();
821:
822: if (allowed) {
823: /* Save temporarily for comparison in verify */
824: key_blob = blob;
825: key_bloblen = bloblen;
826: key_blobtype = type;
827: hostbased_cuser = cuser;
828: hostbased_chost = chost;
1.72 djm 829: } else {
1.77 dtucker 830: /* Log failed attempt */
831: auth_log(authctxt, 0, auth_method, compat20 ? " ssh2" : "");
1.72 djm 832: xfree(blob);
833: xfree(cuser);
834: xfree(chost);
1.1 provos 835: }
836:
837: debug3("%s: key %p is %s",
1.14 markus 838: __func__, key, allowed ? "allowed" : "disallowed");
1.1 provos 839:
840: buffer_clear(m);
841: buffer_put_int(m, allowed);
1.32 markus 842: buffer_put_int(m, forced_command != NULL);
1.1 provos 843:
844: mm_append_debug(m);
845:
1.59 avsm 846: mm_request_send(sock, MONITOR_ANS_KEYALLOWED, m);
1.1 provos 847:
848: if (type == MM_RSAHOSTKEY)
849: monitor_permit(mon_dispatch, MONITOR_REQ_RSACHALLENGE, allowed);
850:
851: return (0);
852: }
853:
854: static int
855: monitor_valid_userblob(u_char *data, u_int datalen)
856: {
857: Buffer b;
1.26 markus 858: char *p;
1.1 provos 859: u_int len;
860: int fail = 0;
861:
862: buffer_init(&b);
863: buffer_append(&b, data, datalen);
1.3 markus 864:
1.1 provos 865: if (datafellows & SSH_OLD_SESSIONID) {
1.13 markus 866: p = buffer_ptr(&b);
867: len = buffer_len(&b);
868: if ((session_id2 == NULL) ||
869: (len < session_id2_len) ||
870: (memcmp(p, session_id2, session_id2_len) != 0))
871: fail++;
1.1 provos 872: buffer_consume(&b, session_id2_len);
873: } else {
1.13 markus 874: p = buffer_get_string(&b, &len);
875: if ((session_id2 == NULL) ||
876: (len != session_id2_len) ||
877: (memcmp(p, session_id2, session_id2_len) != 0))
1.1 provos 878: fail++;
1.13 markus 879: xfree(p);
1.1 provos 880: }
881: if (buffer_get_char(&b) != SSH2_MSG_USERAUTH_REQUEST)
882: fail++;
883: p = buffer_get_string(&b, NULL);
884: if (strcmp(authctxt->user, p) != 0) {
1.38 itojun 885: logit("wrong user name passed to monitor: expected %s != %.100s",
1.1 provos 886: authctxt->user, p);
887: fail++;
888: }
889: xfree(p);
890: buffer_skip_string(&b);
891: if (datafellows & SSH_BUG_PKAUTH) {
892: if (!buffer_get_char(&b))
893: fail++;
894: } else {
895: p = buffer_get_string(&b, NULL);
896: if (strcmp("publickey", p) != 0)
897: fail++;
898: xfree(p);
899: if (!buffer_get_char(&b))
900: fail++;
901: buffer_skip_string(&b);
902: }
903: buffer_skip_string(&b);
904: if (buffer_len(&b) != 0)
905: fail++;
906: buffer_free(&b);
907: return (fail == 0);
908: }
909:
910: static int
1.26 markus 911: monitor_valid_hostbasedblob(u_char *data, u_int datalen, char *cuser,
912: char *chost)
1.1 provos 913: {
914: Buffer b;
1.26 markus 915: char *p;
1.1 provos 916: u_int len;
917: int fail = 0;
918:
919: buffer_init(&b);
920: buffer_append(&b, data, datalen);
1.3 markus 921:
1.13 markus 922: p = buffer_get_string(&b, &len);
923: if ((session_id2 == NULL) ||
924: (len != session_id2_len) ||
925: (memcmp(p, session_id2, session_id2_len) != 0))
1.1 provos 926: fail++;
1.13 markus 927: xfree(p);
928:
1.1 provos 929: if (buffer_get_char(&b) != SSH2_MSG_USERAUTH_REQUEST)
930: fail++;
931: p = buffer_get_string(&b, NULL);
932: if (strcmp(authctxt->user, p) != 0) {
1.38 itojun 933: logit("wrong user name passed to monitor: expected %s != %.100s",
1.1 provos 934: authctxt->user, p);
935: fail++;
936: }
937: xfree(p);
938: buffer_skip_string(&b); /* service */
939: p = buffer_get_string(&b, NULL);
940: if (strcmp(p, "hostbased") != 0)
941: fail++;
942: xfree(p);
943: buffer_skip_string(&b); /* pkalg */
944: buffer_skip_string(&b); /* pkblob */
945:
946: /* verify client host, strip trailing dot if necessary */
947: p = buffer_get_string(&b, NULL);
948: if (((len = strlen(p)) > 0) && p[len - 1] == '.')
949: p[len - 1] = '\0';
950: if (strcmp(p, chost) != 0)
951: fail++;
952: xfree(p);
953:
954: /* verify client user */
955: p = buffer_get_string(&b, NULL);
956: if (strcmp(p, cuser) != 0)
957: fail++;
958: xfree(p);
959:
960: if (buffer_len(&b) != 0)
961: fail++;
962: buffer_free(&b);
963: return (fail == 0);
964: }
965:
966: int
1.59 avsm 967: mm_answer_keyverify(int sock, Buffer *m)
1.1 provos 968: {
969: Key *key;
970: u_char *signature, *data, *blob;
971: u_int signaturelen, datalen, bloblen;
972: int verified = 0;
973: int valid_data = 0;
974:
975: blob = buffer_get_string(m, &bloblen);
976: signature = buffer_get_string(m, &signaturelen);
977: data = buffer_get_string(m, &datalen);
978:
979: if (hostbased_cuser == NULL || hostbased_chost == NULL ||
1.8 mouring 980: !monitor_allowed_key(blob, bloblen))
1.14 markus 981: fatal("%s: bad key, not previously allowed", __func__);
1.1 provos 982:
983: key = key_from_blob(blob, bloblen);
984: if (key == NULL)
1.14 markus 985: fatal("%s: bad public key blob", __func__);
1.1 provos 986:
987: switch (key_blobtype) {
988: case MM_USERKEY:
989: valid_data = monitor_valid_userblob(data, datalen);
990: break;
991: case MM_HOSTKEY:
992: valid_data = monitor_valid_hostbasedblob(data, datalen,
993: hostbased_cuser, hostbased_chost);
994: break;
995: default:
996: valid_data = 0;
997: break;
998: }
999: if (!valid_data)
1.14 markus 1000: fatal("%s: bad signature data blob", __func__);
1.1 provos 1001:
1002: verified = key_verify(key, signature, signaturelen, data, datalen);
1003: debug3("%s: key %p signature %s",
1.14 markus 1004: __func__, key, verified ? "verified" : "unverified");
1.1 provos 1005:
1006: key_free(key);
1007: xfree(blob);
1008: xfree(signature);
1009: xfree(data);
1010:
1.17 stevesk 1011: auth_method = key_blobtype == MM_USERKEY ? "publickey" : "hostbased";
1012:
1.1 provos 1013: monitor_reset_key_state();
1.3 markus 1014:
1.1 provos 1015: buffer_clear(m);
1016: buffer_put_int(m, verified);
1.59 avsm 1017: mm_request_send(sock, MONITOR_ANS_KEYVERIFY, m);
1.1 provos 1018:
1019: return (verified);
1020: }
1021:
1.2 markus 1022: static void
1.1 provos 1023: mm_record_login(Session *s, struct passwd *pw)
1024: {
1025: socklen_t fromlen;
1026: struct sockaddr_storage from;
1027:
1028: /*
1029: * Get IP address of client. If the connection is not a socket, let
1030: * the address be 0.0.0.0.
1031: */
1032: memset(&from, 0, sizeof(from));
1.24 stevesk 1033: fromlen = sizeof(from);
1.1 provos 1034: if (packet_connection_is_on_socket()) {
1035: if (getpeername(packet_get_connection_in(),
1.74 deraadt 1036: (struct sockaddr *)&from, &fromlen) < 0) {
1.1 provos 1037: debug("getpeername: %.100s", strerror(errno));
1.50 markus 1038: cleanup_exit(255);
1.1 provos 1039: }
1040: }
1041: /* Record that there was a login on that tty from the remote host. */
1042: record_login(s->pid, s->tty, pw->pw_name, pw->pw_uid,
1.42 markus 1043: get_remote_name_or_ip(utmp_len, options.use_dns),
1.24 stevesk 1044: (struct sockaddr *)&from, fromlen);
1.1 provos 1045: }
1046:
1047: static void
1048: mm_session_close(Session *s)
1049: {
1.41 djm 1050: debug3("%s: session %d pid %ld", __func__, s->self, (long)s->pid);
1.1 provos 1051: if (s->ttyfd != -1) {
1.14 markus 1052: debug3("%s: tty %s ptyfd %d", __func__, s->tty, s->ptyfd);
1.1 provos 1053: session_pty_cleanup2(s);
1054: }
1055: s->used = 0;
1056: }
1057:
1058: int
1.59 avsm 1059: mm_answer_pty(int sock, Buffer *m)
1.1 provos 1060: {
1.11 mouring 1061: extern struct monitor *pmonitor;
1.1 provos 1062: Session *s;
1063: int res, fd0;
1064:
1.14 markus 1065: debug3("%s entering", __func__);
1.1 provos 1066:
1067: buffer_clear(m);
1068: s = session_new();
1069: if (s == NULL)
1070: goto error;
1071: s->authctxt = authctxt;
1072: s->pw = authctxt->pw;
1.11 mouring 1073: s->pid = pmonitor->m_pid;
1.1 provos 1074: res = pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty));
1075: if (res == 0)
1076: goto error;
1077: pty_setowner(authctxt->pw, s->tty);
1078:
1079: buffer_put_int(m, 1);
1080: buffer_put_cstring(m, s->tty);
1081:
1082: /* We need to trick ttyslot */
1083: if (dup2(s->ttyfd, 0) == -1)
1.14 markus 1084: fatal("%s: dup2", __func__);
1.1 provos 1085:
1086: mm_record_login(s, authctxt->pw);
1087:
1088: /* Now we can close the file descriptor again */
1089: close(0);
1.61 dtucker 1090:
1091: /* send messages generated by record_login */
1092: buffer_put_string(m, buffer_ptr(&loginmsg), buffer_len(&loginmsg));
1093: buffer_clear(&loginmsg);
1094:
1095: mm_request_send(sock, MONITOR_ANS_PTY, m);
1096:
1097: mm_send_fd(sock, s->ptyfd);
1098: mm_send_fd(sock, s->ttyfd);
1.1 provos 1099:
1100: /* make sure nothing uses fd 0 */
1101: if ((fd0 = open(_PATH_DEVNULL, O_RDONLY)) < 0)
1.14 markus 1102: fatal("%s: open(/dev/null): %s", __func__, strerror(errno));
1.1 provos 1103: if (fd0 != 0)
1.14 markus 1104: error("%s: fd0 %d != 0", __func__, fd0);
1.1 provos 1105:
1106: /* slave is not needed */
1107: close(s->ttyfd);
1108: s->ttyfd = s->ptyfd;
1109: /* no need to dup() because nobody closes ptyfd */
1110: s->ptymaster = s->ptyfd;
1111:
1.14 markus 1112: debug3("%s: tty %s ptyfd %d", __func__, s->tty, s->ttyfd);
1.1 provos 1113:
1114: return (0);
1115:
1116: error:
1117: if (s != NULL)
1118: mm_session_close(s);
1119: buffer_put_int(m, 0);
1.59 avsm 1120: mm_request_send(sock, MONITOR_ANS_PTY, m);
1.1 provos 1121: return (0);
1122: }
1123:
1124: int
1.59 avsm 1125: mm_answer_pty_cleanup(int sock, Buffer *m)
1.1 provos 1126: {
1127: Session *s;
1128: char *tty;
1129:
1.14 markus 1130: debug3("%s entering", __func__);
1.1 provos 1131:
1132: tty = buffer_get_string(m, NULL);
1133: if ((s = session_by_tty(tty)) != NULL)
1134: mm_session_close(s);
1135: buffer_clear(m);
1136: xfree(tty);
1137: return (0);
1138: }
1139:
1140: int
1.59 avsm 1141: mm_answer_sesskey(int sock, Buffer *m)
1.1 provos 1142: {
1143: BIGNUM *p;
1144: int rsafail;
1145:
1146: /* Turn off permissions */
1.62 dtucker 1147: monitor_permit(mon_dispatch, MONITOR_REQ_SESSKEY, 0);
1.1 provos 1148:
1149: if ((p = BN_new()) == NULL)
1.14 markus 1150: fatal("%s: BN_new", __func__);
1.1 provos 1151:
1152: buffer_get_bignum2(m, p);
1153:
1154: rsafail = ssh1_session_key(p);
1155:
1156: buffer_clear(m);
1157: buffer_put_int(m, rsafail);
1158: buffer_put_bignum2(m, p);
1159:
1160: BN_clear_free(p);
1161:
1.59 avsm 1162: mm_request_send(sock, MONITOR_ANS_SESSKEY, m);
1.1 provos 1163:
1164: /* Turn on permissions for sessid passing */
1165: monitor_permit(mon_dispatch, MONITOR_REQ_SESSID, 1);
1166:
1167: return (0);
1168: }
1169:
1170: int
1.59 avsm 1171: mm_answer_sessid(int sock, Buffer *m)
1.1 provos 1172: {
1173: int i;
1174:
1.14 markus 1175: debug3("%s entering", __func__);
1.1 provos 1176:
1177: if (buffer_len(m) != 16)
1.14 markus 1178: fatal("%s: bad ssh1 session id", __func__);
1.1 provos 1179: for (i = 0; i < 16; i++)
1180: session_id[i] = buffer_get_char(m);
1181:
1182: /* Turn on permissions for getpwnam */
1183: monitor_permit(mon_dispatch, MONITOR_REQ_PWNAM, 1);
1184:
1185: return (0);
1186: }
1187:
1188: int
1.59 avsm 1189: mm_answer_rsa_keyallowed(int sock, Buffer *m)
1.1 provos 1190: {
1191: BIGNUM *client_n;
1192: Key *key = NULL;
1.3 markus 1193: u_char *blob = NULL;
1194: u_int blen = 0;
1.1 provos 1195: int allowed = 0;
1196:
1.14 markus 1197: debug3("%s entering", __func__);
1.1 provos 1198:
1.77 dtucker 1199: auth_method = "rsa";
1.12 markus 1200: if (options.rsa_authentication && authctxt->valid) {
1.1 provos 1201: if ((client_n = BN_new()) == NULL)
1.14 markus 1202: fatal("%s: BN_new", __func__);
1.1 provos 1203: buffer_get_bignum2(m, client_n);
1204: allowed = auth_rsa_key_allowed(authctxt->pw, client_n, &key);
1205: BN_clear_free(client_n);
1206: }
1207: buffer_clear(m);
1208: buffer_put_int(m, allowed);
1.32 markus 1209: buffer_put_int(m, forced_command != NULL);
1.1 provos 1210:
1211: /* clear temporarily storage (used by generate challenge) */
1212: monitor_reset_key_state();
1213:
1214: if (allowed && key != NULL) {
1215: key->type = KEY_RSA; /* cheat for key_to_blob */
1216: if (key_to_blob(key, &blob, &blen) == 0)
1.14 markus 1217: fatal("%s: key_to_blob failed", __func__);
1.1 provos 1218: buffer_put_string(m, blob, blen);
1219:
1220: /* Save temporarily for comparison in verify */
1221: key_blob = blob;
1222: key_bloblen = blen;
1223: key_blobtype = MM_RSAUSERKEY;
1.33 markus 1224: }
1225: if (key != NULL)
1.1 provos 1226: key_free(key);
1227:
1228: mm_append_debug(m);
1229:
1.59 avsm 1230: mm_request_send(sock, MONITOR_ANS_RSAKEYALLOWED, m);
1.1 provos 1231:
1232: monitor_permit(mon_dispatch, MONITOR_REQ_RSACHALLENGE, allowed);
1233: monitor_permit(mon_dispatch, MONITOR_REQ_RSARESPONSE, 0);
1234: return (0);
1235: }
1236:
1237: int
1.59 avsm 1238: mm_answer_rsa_challenge(int sock, Buffer *m)
1.1 provos 1239: {
1240: Key *key = NULL;
1.3 markus 1241: u_char *blob;
1242: u_int blen;
1.1 provos 1243:
1.14 markus 1244: debug3("%s entering", __func__);
1.1 provos 1245:
1246: if (!authctxt->valid)
1.14 markus 1247: fatal("%s: authctxt not valid", __func__);
1.1 provos 1248: blob = buffer_get_string(m, &blen);
1249: if (!monitor_allowed_key(blob, blen))
1.14 markus 1250: fatal("%s: bad key, not previously allowed", __func__);
1.1 provos 1251: if (key_blobtype != MM_RSAUSERKEY && key_blobtype != MM_RSAHOSTKEY)
1.14 markus 1252: fatal("%s: key type mismatch", __func__);
1.1 provos 1253: if ((key = key_from_blob(blob, blen)) == NULL)
1.14 markus 1254: fatal("%s: received bad key", __func__);
1.1 provos 1255:
1256: if (ssh1_challenge)
1257: BN_clear_free(ssh1_challenge);
1258: ssh1_challenge = auth_rsa_generate_challenge(key);
1259:
1260: buffer_clear(m);
1261: buffer_put_bignum2(m, ssh1_challenge);
1262:
1.14 markus 1263: debug3("%s sending reply", __func__);
1.59 avsm 1264: mm_request_send(sock, MONITOR_ANS_RSACHALLENGE, m);
1.1 provos 1265:
1266: monitor_permit(mon_dispatch, MONITOR_REQ_RSARESPONSE, 1);
1.33 markus 1267:
1268: xfree(blob);
1269: key_free(key);
1.1 provos 1270: return (0);
1271: }
1272:
1273: int
1.59 avsm 1274: mm_answer_rsa_response(int sock, Buffer *m)
1.1 provos 1275: {
1276: Key *key = NULL;
1.3 markus 1277: u_char *blob, *response;
1278: u_int blen, len;
1279: int success;
1.1 provos 1280:
1.14 markus 1281: debug3("%s entering", __func__);
1.1 provos 1282:
1283: if (!authctxt->valid)
1.14 markus 1284: fatal("%s: authctxt not valid", __func__);
1.1 provos 1285: if (ssh1_challenge == NULL)
1.14 markus 1286: fatal("%s: no ssh1_challenge", __func__);
1.1 provos 1287:
1288: blob = buffer_get_string(m, &blen);
1289: if (!monitor_allowed_key(blob, blen))
1.14 markus 1290: fatal("%s: bad key, not previously allowed", __func__);
1.1 provos 1291: if (key_blobtype != MM_RSAUSERKEY && key_blobtype != MM_RSAHOSTKEY)
1.14 markus 1292: fatal("%s: key type mismatch: %d", __func__, key_blobtype);
1.1 provos 1293: if ((key = key_from_blob(blob, blen)) == NULL)
1.14 markus 1294: fatal("%s: received bad key", __func__);
1.1 provos 1295: response = buffer_get_string(m, &len);
1296: if (len != 16)
1.14 markus 1297: fatal("%s: received bad response to challenge", __func__);
1.1 provos 1298: success = auth_rsa_verify_response(key, ssh1_challenge, response);
1299:
1.33 markus 1300: xfree(blob);
1.1 provos 1301: key_free(key);
1302: xfree(response);
1303:
1304: auth_method = key_blobtype == MM_RSAUSERKEY ? "rsa" : "rhosts-rsa";
1305:
1306: /* reset state */
1307: BN_clear_free(ssh1_challenge);
1308: ssh1_challenge = NULL;
1309: monitor_reset_key_state();
1310:
1311: buffer_clear(m);
1312: buffer_put_int(m, success);
1.59 avsm 1313: mm_request_send(sock, MONITOR_ANS_RSARESPONSE, m);
1.1 provos 1314:
1315: return (success);
1316: }
1317:
1318: int
1.59 avsm 1319: mm_answer_term(int sock, Buffer *req)
1.1 provos 1320: {
1.11 mouring 1321: extern struct monitor *pmonitor;
1.1 provos 1322: int res, status;
1323:
1.14 markus 1324: debug3("%s: tearing down sessions", __func__);
1.1 provos 1325:
1326: /* The child is terminating */
1327: session_destroy_all(&mm_session_close);
1328:
1.11 mouring 1329: while (waitpid(pmonitor->m_pid, &status, 0) == -1)
1.9 markus 1330: if (errno != EINTR)
1331: exit(1);
1.1 provos 1332:
1333: res = WIFEXITED(status) ? WEXITSTATUS(status) : 1;
1334:
1335: /* Terminate process */
1.57 deraadt 1336: exit(res);
1.1 provos 1337: }
1338:
1339: void
1.11 mouring 1340: monitor_apply_keystate(struct monitor *pmonitor)
1.1 provos 1341: {
1342: if (compat20) {
1343: set_newkeys(MODE_IN);
1344: set_newkeys(MODE_OUT);
1345: } else {
1346: packet_set_protocol_flags(child_state.ssh1protoflags);
1.15 markus 1347: packet_set_encryption_key(child_state.ssh1key,
1348: child_state.ssh1keylen, child_state.ssh1cipher);
1349: xfree(child_state.ssh1key);
1.1 provos 1350: }
1351:
1.15 markus 1352: /* for rc4 and other stateful ciphers */
1.1 provos 1353: packet_set_keycontext(MODE_OUT, child_state.keyout);
1354: xfree(child_state.keyout);
1355: packet_set_keycontext(MODE_IN, child_state.keyin);
1356: xfree(child_state.keyin);
1357:
1358: if (!compat20) {
1359: packet_set_iv(MODE_OUT, child_state.ivout);
1360: xfree(child_state.ivout);
1361: packet_set_iv(MODE_IN, child_state.ivin);
1362: xfree(child_state.ivin);
1363: }
1364:
1365: memcpy(&incoming_stream, &child_state.incoming,
1366: sizeof(incoming_stream));
1367: memcpy(&outgoing_stream, &child_state.outgoing,
1368: sizeof(outgoing_stream));
1.3 markus 1369:
1.1 provos 1370: /* Update with new address */
1.16 djm 1371: if (options.compression)
1372: mm_init_compression(pmonitor->m_zlib);
1.1 provos 1373:
1374: /* Network I/O buffers */
1375: /* XXX inefficient for large buffers, need: buffer_init_from_string */
1376: buffer_clear(&input);
1377: buffer_append(&input, child_state.input, child_state.ilen);
1378: memset(child_state.input, 0, child_state.ilen);
1379: xfree(child_state.input);
1380:
1381: buffer_clear(&output);
1382: buffer_append(&output, child_state.output, child_state.olen);
1383: memset(child_state.output, 0, child_state.olen);
1384: xfree(child_state.output);
1385: }
1386:
1.2 markus 1387: static Kex *
1.1 provos 1388: mm_get_kex(Buffer *m)
1389: {
1390: Kex *kex;
1391: void *blob;
1392: u_int bloblen;
1393:
1.75 djm 1394: kex = xcalloc(1, sizeof(*kex));
1.1 provos 1395: kex->session_id = buffer_get_string(m, &kex->session_id_len);
1.13 markus 1396: if ((session_id2 == NULL) ||
1397: (kex->session_id_len != session_id2_len) ||
1398: (memcmp(kex->session_id, session_id2, session_id2_len) != 0))
1399: fatal("mm_get_get: internal error: bad session id");
1.1 provos 1400: kex->we_need = buffer_get_int(m);
1.34 markus 1401: kex->kex[KEX_DH_GRP1_SHA1] = kexdh_server;
1.58 djm 1402: kex->kex[KEX_DH_GRP14_SHA1] = kexdh_server;
1.34 markus 1403: kex->kex[KEX_DH_GEX_SHA1] = kexgex_server;
1.69 djm 1404: kex->kex[KEX_DH_GEX_SHA256] = kexgex_server;
1.1 provos 1405: kex->server = 1;
1406: kex->hostkey_type = buffer_get_int(m);
1407: kex->kex_type = buffer_get_int(m);
1408: blob = buffer_get_string(m, &bloblen);
1409: buffer_init(&kex->my);
1410: buffer_append(&kex->my, blob, bloblen);
1411: xfree(blob);
1412: blob = buffer_get_string(m, &bloblen);
1413: buffer_init(&kex->peer);
1414: buffer_append(&kex->peer, blob, bloblen);
1415: xfree(blob);
1416: kex->done = 1;
1417: kex->flags = buffer_get_int(m);
1418: kex->client_version_string = buffer_get_string(m, NULL);
1419: kex->server_version_string = buffer_get_string(m, NULL);
1420: kex->load_host_key=&get_hostkey_by_type;
1421: kex->host_key_index=&get_hostkey_index;
1422:
1423: return (kex);
1424: }
1425:
1426: /* This function requries careful sanity checking */
1427:
1428: void
1.11 mouring 1429: mm_get_keystate(struct monitor *pmonitor)
1.1 provos 1430: {
1431: Buffer m;
1432: u_char *blob, *p;
1433: u_int bloblen, plen;
1.37 markus 1434: u_int32_t seqnr, packets;
1435: u_int64_t blocks;
1.1 provos 1436:
1.14 markus 1437: debug3("%s: Waiting for new keys", __func__);
1.1 provos 1438:
1439: buffer_init(&m);
1.11 mouring 1440: mm_request_receive_expect(pmonitor->m_sendfd, MONITOR_REQ_KEYEXPORT, &m);
1.1 provos 1441: if (!compat20) {
1442: child_state.ssh1protoflags = buffer_get_int(&m);
1443: child_state.ssh1cipher = buffer_get_int(&m);
1.15 markus 1444: child_state.ssh1key = buffer_get_string(&m,
1445: &child_state.ssh1keylen);
1.1 provos 1446: child_state.ivout = buffer_get_string(&m,
1447: &child_state.ivoutlen);
1448: child_state.ivin = buffer_get_string(&m, &child_state.ivinlen);
1449: goto skip;
1450: } else {
1451: /* Get the Kex for rekeying */
1.11 mouring 1452: *pmonitor->m_pkex = mm_get_kex(&m);
1.1 provos 1453: }
1454:
1455: blob = buffer_get_string(&m, &bloblen);
1456: current_keys[MODE_OUT] = mm_newkeys_from_blob(blob, bloblen);
1457: xfree(blob);
1458:
1.14 markus 1459: debug3("%s: Waiting for second key", __func__);
1.1 provos 1460: blob = buffer_get_string(&m, &bloblen);
1461: current_keys[MODE_IN] = mm_newkeys_from_blob(blob, bloblen);
1462: xfree(blob);
1.3 markus 1463:
1.1 provos 1464: /* Now get sequence numbers for the packets */
1.37 markus 1465: seqnr = buffer_get_int(&m);
1466: blocks = buffer_get_int64(&m);
1467: packets = buffer_get_int(&m);
1468: packet_set_state(MODE_OUT, seqnr, blocks, packets);
1469: seqnr = buffer_get_int(&m);
1470: blocks = buffer_get_int64(&m);
1471: packets = buffer_get_int(&m);
1472: packet_set_state(MODE_IN, seqnr, blocks, packets);
1.1 provos 1473:
1474: skip:
1475: /* Get the key context */
1476: child_state.keyout = buffer_get_string(&m, &child_state.keyoutlen);
1477: child_state.keyin = buffer_get_string(&m, &child_state.keyinlen);
1478:
1.14 markus 1479: debug3("%s: Getting compression state", __func__);
1.1 provos 1480: /* Get compression state */
1481: p = buffer_get_string(&m, &plen);
1482: if (plen != sizeof(child_state.outgoing))
1.14 markus 1483: fatal("%s: bad request size", __func__);
1.1 provos 1484: memcpy(&child_state.outgoing, p, sizeof(child_state.outgoing));
1485: xfree(p);
1486:
1487: p = buffer_get_string(&m, &plen);
1488: if (plen != sizeof(child_state.incoming))
1.14 markus 1489: fatal("%s: bad request size", __func__);
1.1 provos 1490: memcpy(&child_state.incoming, p, sizeof(child_state.incoming));
1491: xfree(p);
1492:
1493: /* Network I/O buffers */
1.14 markus 1494: debug3("%s: Getting Network I/O buffers", __func__);
1.1 provos 1495: child_state.input = buffer_get_string(&m, &child_state.ilen);
1496: child_state.output = buffer_get_string(&m, &child_state.olen);
1497:
1498: buffer_free(&m);
1499: }
1500:
1501:
1502: /* Allocation functions for zlib */
1503: void *
1504: mm_zalloc(struct mm_master *mm, u_int ncount, u_int size)
1505: {
1.30 markus 1506: size_t len = (size_t) size * ncount;
1.1 provos 1507: void *address;
1508:
1.23 millert 1509: if (len == 0 || ncount > SIZE_T_MAX / size)
1.18 deraadt 1510: fatal("%s: mm_zalloc(%u, %u)", __func__, ncount, size);
1511:
1512: address = mm_malloc(mm, len);
1.1 provos 1513:
1514: return (address);
1515: }
1516:
1517: void
1518: mm_zfree(struct mm_master *mm, void *address)
1519: {
1520: mm_free(mm, address);
1521: }
1522:
1523: void
1524: mm_init_compression(struct mm_master *mm)
1525: {
1526: outgoing_stream.zalloc = (alloc_func)mm_zalloc;
1527: outgoing_stream.zfree = (free_func)mm_zfree;
1528: outgoing_stream.opaque = mm;
1529:
1530: incoming_stream.zalloc = (alloc_func)mm_zalloc;
1531: incoming_stream.zfree = (free_func)mm_zfree;
1532: incoming_stream.opaque = mm;
1533: }
1534:
1535: /* XXX */
1536:
1537: #define FD_CLOSEONEXEC(x) do { \
1538: if (fcntl(x, F_SETFD, 1) == -1) \
1539: fatal("fcntl(%d, F_SETFD)", x); \
1540: } while (0)
1541:
1.2 markus 1542: static void
1.1 provos 1543: monitor_socketpair(int *pair)
1.3 markus 1544: {
1.1 provos 1545: if (socketpair(AF_UNIX, SOCK_STREAM, 0, pair) == -1)
1.14 markus 1546: fatal("%s: socketpair", __func__);
1.1 provos 1547: FD_CLOSEONEXEC(pair[0]);
1548: FD_CLOSEONEXEC(pair[1]);
1549: }
1550:
1551: #define MM_MEMSIZE 65536
1552:
1553: struct monitor *
1554: monitor_init(void)
1555: {
1556: struct monitor *mon;
1557: int pair[2];
1558:
1.75 djm 1559: mon = xcalloc(1, sizeof(*mon));
1.1 provos 1560:
1561: monitor_socketpair(pair);
1562:
1563: mon->m_recvfd = pair[0];
1564: mon->m_sendfd = pair[1];
1565:
1566: /* Used to share zlib space across processes */
1.16 djm 1567: if (options.compression) {
1568: mon->m_zback = mm_create(NULL, MM_MEMSIZE);
1569: mon->m_zlib = mm_create(mon->m_zback, 20 * MM_MEMSIZE);
1.1 provos 1570:
1.16 djm 1571: /* Compression needs to share state across borders */
1572: mm_init_compression(mon->m_zlib);
1573: }
1.1 provos 1574:
1575: return mon;
1576: }
1577:
1578: void
1579: monitor_reinit(struct monitor *mon)
1580: {
1581: int pair[2];
1582:
1583: monitor_socketpair(pair);
1584:
1585: mon->m_recvfd = pair[0];
1586: mon->m_sendfd = pair[1];
1587: }
1.46 markus 1588:
1589: #ifdef GSSAPI
1590: int
1.59 avsm 1591: mm_answer_gss_setup_ctx(int sock, Buffer *m)
1.46 markus 1592: {
1.59 avsm 1593: gss_OID_desc goid;
1.46 markus 1594: OM_uint32 major;
1595: u_int len;
1596:
1.59 avsm 1597: goid.elements = buffer_get_string(m, &len);
1598: goid.length = len;
1.46 markus 1599:
1.59 avsm 1600: major = ssh_gssapi_server_ctx(&gsscontext, &goid);
1.46 markus 1601:
1.59 avsm 1602: xfree(goid.elements);
1.46 markus 1603:
1604: buffer_clear(m);
1605: buffer_put_int(m, major);
1606:
1.64 stevesk 1607: mm_request_send(sock, MONITOR_ANS_GSSSETUP, m);
1.46 markus 1608:
1609: /* Now we have a context, enable the step */
1610: monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 1);
1611:
1612: return (0);
1613: }
1614:
1615: int
1.59 avsm 1616: mm_answer_gss_accept_ctx(int sock, Buffer *m)
1.46 markus 1617: {
1618: gss_buffer_desc in;
1619: gss_buffer_desc out = GSS_C_EMPTY_BUFFER;
1.64 stevesk 1620: OM_uint32 major, minor;
1.46 markus 1621: OM_uint32 flags = 0; /* GSI needs this */
1.47 deraadt 1622: u_int len;
1.46 markus 1623:
1.47 deraadt 1624: in.value = buffer_get_string(m, &len);
1625: in.length = len;
1.46 markus 1626: major = ssh_gssapi_accept_ctx(gsscontext, &in, &out, &flags);
1627: xfree(in.value);
1628:
1629: buffer_clear(m);
1630: buffer_put_int(m, major);
1631: buffer_put_string(m, out.value, out.length);
1632: buffer_put_int(m, flags);
1.59 avsm 1633: mm_request_send(sock, MONITOR_ANS_GSSSTEP, m);
1.46 markus 1634:
1635: gss_release_buffer(&minor, &out);
1636:
1.64 stevesk 1637: if (major == GSS_S_COMPLETE) {
1.46 markus 1638: monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 0);
1639: monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
1.52 markus 1640: monitor_permit(mon_dispatch, MONITOR_REQ_GSSCHECKMIC, 1);
1.46 markus 1641: }
1642: return (0);
1643: }
1644:
1645: int
1.59 avsm 1646: mm_answer_gss_checkmic(int sock, Buffer *m)
1.52 markus 1647: {
1648: gss_buffer_desc gssbuf, mic;
1649: OM_uint32 ret;
1650: u_int len;
1.54 djm 1651:
1.52 markus 1652: gssbuf.value = buffer_get_string(m, &len);
1653: gssbuf.length = len;
1654: mic.value = buffer_get_string(m, &len);
1655: mic.length = len;
1.54 djm 1656:
1.52 markus 1657: ret = ssh_gssapi_checkmic(gsscontext, &gssbuf, &mic);
1.54 djm 1658:
1.52 markus 1659: xfree(gssbuf.value);
1660: xfree(mic.value);
1.54 djm 1661:
1.52 markus 1662: buffer_clear(m);
1663: buffer_put_int(m, ret);
1.54 djm 1664:
1.59 avsm 1665: mm_request_send(sock, MONITOR_ANS_GSSCHECKMIC, m);
1.54 djm 1666:
1.52 markus 1667: if (!GSS_ERROR(ret))
1668: monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
1.54 djm 1669:
1.52 markus 1670: return (0);
1671: }
1672:
1673: int
1.59 avsm 1674: mm_answer_gss_userok(int sock, Buffer *m)
1.46 markus 1675: {
1676: int authenticated;
1677:
1678: authenticated = authctxt->valid && ssh_gssapi_userok(authctxt->user);
1679:
1680: buffer_clear(m);
1681: buffer_put_int(m, authenticated);
1682:
1683: debug3("%s: sending result %d", __func__, authenticated);
1.59 avsm 1684: mm_request_send(sock, MONITOR_ANS_GSSUSEROK, m);
1.46 markus 1685:
1.64 stevesk 1686: auth_method = "gssapi-with-mic";
1.46 markus 1687:
1688: /* Monitor loop will terminate if authenticated */
1689: return (authenticated);
1690: }
1691: #endif /* GSSAPI */
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