Annotation of src/usr.bin/ssh/monitor.c, Revision 1.79
1.79 ! stevesk 1: /* $OpenBSD: monitor.c,v 1.78 2006/07/06 16:03:53 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:
1.65 stevesk 36: #include <paths.h>
1.78 stevesk 37: #include <pwd.h>
1.68 stevesk 38: #include <signal.h>
1.1 provos 39:
40: #ifdef SKEY
41: #include <skey.h>
42: #endif
43:
44: #include "ssh.h"
45: #include "auth.h"
46: #include "kex.h"
47: #include "dh.h"
48: #include "zlib.h"
49: #include "packet.h"
50: #include "auth-options.h"
51: #include "sshpty.h"
52: #include "channels.h"
53: #include "session.h"
54: #include "sshlogin.h"
55: #include "canohost.h"
56: #include "log.h"
57: #include "servconf.h"
58: #include "monitor.h"
59: #include "monitor_mm.h"
60: #include "monitor_wrap.h"
61: #include "monitor_fdpass.h"
62: #include "xmalloc.h"
63: #include "misc.h"
64: #include "buffer.h"
65: #include "bufaux.h"
66: #include "compat.h"
67: #include "ssh2.h"
68:
1.46 markus 69: #ifdef GSSAPI
70: #include "ssh-gss.h"
71: static Gssctxt *gsscontext = NULL;
72: #endif
73:
1.1 provos 74: /* Imports */
75: extern ServerOptions options;
76: extern u_int utmp_len;
77: extern Newkeys *current_keys[];
78: extern z_stream incoming_stream;
79: extern z_stream outgoing_stream;
80: extern u_char session_id[];
81: extern Buffer input, output;
82: extern Buffer auth_debug;
83: extern int auth_debug_init;
1.61 dtucker 84: extern Buffer loginmsg;
1.1 provos 85:
86: /* State exported from the child */
87:
88: struct {
89: z_stream incoming;
90: z_stream outgoing;
91: u_char *keyin;
92: u_int keyinlen;
93: u_char *keyout;
94: u_int keyoutlen;
95: u_char *ivin;
96: u_int ivinlen;
97: u_char *ivout;
98: u_int ivoutlen;
1.15 markus 99: u_char *ssh1key;
100: u_int ssh1keylen;
1.1 provos 101: int ssh1cipher;
102: int ssh1protoflags;
103: u_char *input;
104: u_int ilen;
105: u_char *output;
106: u_int olen;
107: } child_state;
108:
1.43 markus 109: /* Functions on the monitor that answer unprivileged requests */
1.1 provos 110:
111: int mm_answer_moduli(int, Buffer *);
112: int mm_answer_sign(int, Buffer *);
113: int mm_answer_pwnamallow(int, Buffer *);
1.10 djm 114: int mm_answer_auth2_read_banner(int, Buffer *);
1.1 provos 115: int mm_answer_authserv(int, Buffer *);
116: int mm_answer_authpassword(int, Buffer *);
117: int mm_answer_bsdauthquery(int, Buffer *);
118: int mm_answer_bsdauthrespond(int, Buffer *);
119: int mm_answer_skeyquery(int, Buffer *);
120: int mm_answer_skeyrespond(int, Buffer *);
121: int mm_answer_keyallowed(int, Buffer *);
122: int mm_answer_keyverify(int, Buffer *);
123: int mm_answer_pty(int, Buffer *);
124: int mm_answer_pty_cleanup(int, Buffer *);
125: int mm_answer_term(int, Buffer *);
126: int mm_answer_rsa_keyallowed(int, Buffer *);
127: int mm_answer_rsa_challenge(int, Buffer *);
128: int mm_answer_rsa_response(int, Buffer *);
129: int mm_answer_sesskey(int, Buffer *);
130: int mm_answer_sessid(int, Buffer *);
131:
1.46 markus 132: #ifdef GSSAPI
133: int mm_answer_gss_setup_ctx(int, Buffer *);
134: int mm_answer_gss_accept_ctx(int, Buffer *);
135: int mm_answer_gss_userok(int, Buffer *);
1.52 markus 136: int mm_answer_gss_checkmic(int, Buffer *);
1.46 markus 137: #endif
1.25 itojun 138:
1.1 provos 139: static Authctxt *authctxt;
140: static BIGNUM *ssh1_challenge = NULL; /* used for ssh1 rsa auth */
141:
142: /* local state for key verify */
143: static u_char *key_blob = NULL;
144: static u_int key_bloblen = 0;
145: static int key_blobtype = MM_NOKEY;
1.26 markus 146: static char *hostbased_cuser = NULL;
147: static char *hostbased_chost = NULL;
1.1 provos 148: static char *auth_method = "unknown";
1.44 markus 149: static u_int session_id2_len = 0;
1.13 markus 150: static u_char *session_id2 = NULL;
1.40 markus 151: static pid_t monitor_child_pid;
1.1 provos 152:
153: struct mon_table {
154: enum monitor_reqtype type;
155: int flags;
156: int (*f)(int, Buffer *);
157: };
158:
159: #define MON_ISAUTH 0x0004 /* Required for Authentication */
160: #define MON_AUTHDECIDE 0x0008 /* Decides Authentication */
161: #define MON_ONCE 0x0010 /* Disable after calling */
1.77 dtucker 162: #define MON_ALOG 0x0020 /* Log auth attempt without authenticating */
1.1 provos 163:
164: #define MON_AUTH (MON_ISAUTH|MON_AUTHDECIDE)
165:
166: #define MON_PERMIT 0x1000 /* Request is permitted */
167:
168: struct mon_table mon_dispatch_proto20[] = {
169: {MONITOR_REQ_MODULI, MON_ONCE, mm_answer_moduli},
170: {MONITOR_REQ_SIGN, MON_ONCE, mm_answer_sign},
171: {MONITOR_REQ_PWNAM, MON_ONCE, mm_answer_pwnamallow},
172: {MONITOR_REQ_AUTHSERV, MON_ONCE, mm_answer_authserv},
1.10 djm 173: {MONITOR_REQ_AUTH2_READ_BANNER, MON_ONCE, mm_answer_auth2_read_banner},
1.1 provos 174: {MONITOR_REQ_AUTHPASSWORD, MON_AUTH, mm_answer_authpassword},
175: #ifdef BSD_AUTH
176: {MONITOR_REQ_BSDAUTHQUERY, MON_ISAUTH, mm_answer_bsdauthquery},
1.66 stevesk 177: {MONITOR_REQ_BSDAUTHRESPOND, MON_AUTH, mm_answer_bsdauthrespond},
1.1 provos 178: #endif
179: #ifdef SKEY
180: {MONITOR_REQ_SKEYQUERY, MON_ISAUTH, mm_answer_skeyquery},
181: {MONITOR_REQ_SKEYRESPOND, MON_AUTH, mm_answer_skeyrespond},
182: #endif
183: {MONITOR_REQ_KEYALLOWED, MON_ISAUTH, mm_answer_keyallowed},
184: {MONITOR_REQ_KEYVERIFY, MON_AUTH, mm_answer_keyverify},
1.46 markus 185: #ifdef GSSAPI
186: {MONITOR_REQ_GSSSETUP, MON_ISAUTH, mm_answer_gss_setup_ctx},
187: {MONITOR_REQ_GSSSTEP, MON_ISAUTH, mm_answer_gss_accept_ctx},
188: {MONITOR_REQ_GSSUSEROK, MON_AUTH, mm_answer_gss_userok},
1.52 markus 189: {MONITOR_REQ_GSSCHECKMIC, MON_ISAUTH, mm_answer_gss_checkmic},
1.46 markus 190: #endif
1.1 provos 191: {0, 0, NULL}
192: };
193:
194: struct mon_table mon_dispatch_postauth20[] = {
195: {MONITOR_REQ_MODULI, 0, mm_answer_moduli},
196: {MONITOR_REQ_SIGN, 0, mm_answer_sign},
197: {MONITOR_REQ_PTY, 0, mm_answer_pty},
198: {MONITOR_REQ_PTYCLEANUP, 0, mm_answer_pty_cleanup},
199: {MONITOR_REQ_TERM, 0, mm_answer_term},
200: {0, 0, NULL}
201: };
202:
203: struct mon_table mon_dispatch_proto15[] = {
204: {MONITOR_REQ_PWNAM, MON_ONCE, mm_answer_pwnamallow},
205: {MONITOR_REQ_SESSKEY, MON_ONCE, mm_answer_sesskey},
206: {MONITOR_REQ_SESSID, MON_ONCE, mm_answer_sessid},
207: {MONITOR_REQ_AUTHPASSWORD, MON_AUTH, mm_answer_authpassword},
1.77 dtucker 208: {MONITOR_REQ_RSAKEYALLOWED, MON_ISAUTH|MON_ALOG, mm_answer_rsa_keyallowed},
209: {MONITOR_REQ_KEYALLOWED, MON_ISAUTH|MON_ALOG, mm_answer_keyallowed},
1.1 provos 210: {MONITOR_REQ_RSACHALLENGE, MON_ONCE, mm_answer_rsa_challenge},
211: {MONITOR_REQ_RSARESPONSE, MON_ONCE|MON_AUTHDECIDE, mm_answer_rsa_response},
212: #ifdef BSD_AUTH
213: {MONITOR_REQ_BSDAUTHQUERY, MON_ISAUTH, mm_answer_bsdauthquery},
1.66 stevesk 214: {MONITOR_REQ_BSDAUTHRESPOND, MON_AUTH, mm_answer_bsdauthrespond},
1.1 provos 215: #endif
216: #ifdef SKEY
217: {MONITOR_REQ_SKEYQUERY, MON_ISAUTH, mm_answer_skeyquery},
218: {MONITOR_REQ_SKEYRESPOND, MON_AUTH, mm_answer_skeyrespond},
219: #endif
220: {0, 0, NULL}
221: };
222:
223: struct mon_table mon_dispatch_postauth15[] = {
224: {MONITOR_REQ_PTY, MON_ONCE, mm_answer_pty},
225: {MONITOR_REQ_PTYCLEANUP, MON_ONCE, mm_answer_pty_cleanup},
226: {MONITOR_REQ_TERM, 0, mm_answer_term},
227: {0, 0, NULL}
228: };
229:
230: struct mon_table *mon_dispatch;
231:
232: /* Specifies if a certain message is allowed at the moment */
233:
234: static void
235: monitor_permit(struct mon_table *ent, enum monitor_reqtype type, int permit)
236: {
237: while (ent->f != NULL) {
238: if (ent->type == type) {
239: ent->flags &= ~MON_PERMIT;
240: ent->flags |= permit ? MON_PERMIT : 0;
241: return;
242: }
243: ent++;
244: }
245: }
246:
247: static void
248: monitor_permit_authentications(int permit)
249: {
250: struct mon_table *ent = mon_dispatch;
251:
252: while (ent->f != NULL) {
253: if (ent->flags & MON_AUTH) {
254: ent->flags &= ~MON_PERMIT;
255: ent->flags |= permit ? MON_PERMIT : 0;
256: }
257: ent++;
258: }
259: }
260:
1.50 markus 261: void
262: monitor_child_preauth(Authctxt *_authctxt, struct monitor *pmonitor)
1.1 provos 263: {
264: struct mon_table *ent;
265: int authenticated = 0;
266:
267: debug3("preauth child monitor started");
268:
1.50 markus 269: authctxt = _authctxt;
270: memset(authctxt, 0, sizeof(*authctxt));
271:
1.1 provos 272: if (compat20) {
273: mon_dispatch = mon_dispatch_proto20;
274:
275: /* Permit requests for moduli and signatures */
276: monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
277: monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
278: } else {
279: mon_dispatch = mon_dispatch_proto15;
280:
281: monitor_permit(mon_dispatch, MONITOR_REQ_SESSKEY, 1);
282: }
283:
284: /* The first few requests do not require asynchronous access */
285: while (!authenticated) {
1.77 dtucker 286: auth_method = "unknown";
1.11 mouring 287: authenticated = monitor_read(pmonitor, mon_dispatch, &ent);
1.1 provos 288: if (authenticated) {
289: if (!(ent->flags & MON_AUTHDECIDE))
290: fatal("%s: unexpected authentication from %d",
1.14 markus 291: __func__, ent->type);
1.1 provos 292: if (authctxt->pw->pw_uid == 0 &&
293: !auth_root_allowed(auth_method))
294: authenticated = 0;
295: }
296:
1.77 dtucker 297: if (ent->flags & (MON_AUTHDECIDE|MON_ALOG)) {
1.1 provos 298: auth_log(authctxt, authenticated, auth_method,
299: compat20 ? " ssh2" : "");
300: if (!authenticated)
301: authctxt->failures++;
302: }
303: }
304:
305: if (!authctxt->valid)
1.14 markus 306: fatal("%s: authenticated invalid user", __func__);
1.77 dtucker 307: if (strcmp(auth_method, "unknown") == 0)
308: fatal("%s: authentication method name unknown", __func__);
1.1 provos 309:
310: debug("%s: %s has been authenticated by privileged process",
1.14 markus 311: __func__, authctxt->user);
1.1 provos 312:
1.11 mouring 313: mm_get_keystate(pmonitor);
1.1 provos 314: }
315:
1.40 markus 316: static void
317: monitor_set_child_handler(pid_t pid)
318: {
319: monitor_child_pid = pid;
320: }
321:
322: static void
1.59 avsm 323: monitor_child_handler(int sig)
1.40 markus 324: {
1.59 avsm 325: kill(monitor_child_pid, sig);
1.40 markus 326: }
327:
1.1 provos 328: void
1.11 mouring 329: monitor_child_postauth(struct monitor *pmonitor)
1.1 provos 330: {
1.40 markus 331: monitor_set_child_handler(pmonitor->m_pid);
332: signal(SIGHUP, &monitor_child_handler);
333: signal(SIGTERM, &monitor_child_handler);
334:
1.1 provos 335: if (compat20) {
336: mon_dispatch = mon_dispatch_postauth20;
337:
338: /* Permit requests for moduli and signatures */
339: monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
340: monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
341: monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1);
342: } else {
343: mon_dispatch = mon_dispatch_postauth15;
344: monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1);
345: }
346: if (!no_pty_flag) {
347: monitor_permit(mon_dispatch, MONITOR_REQ_PTY, 1);
348: monitor_permit(mon_dispatch, MONITOR_REQ_PTYCLEANUP, 1);
349: }
350:
351: for (;;)
1.11 mouring 352: monitor_read(pmonitor, mon_dispatch, NULL);
1.1 provos 353: }
354:
355: void
1.11 mouring 356: monitor_sync(struct monitor *pmonitor)
1.1 provos 357: {
1.16 djm 358: if (options.compression) {
359: /* The member allocation is not visible, so sync it */
360: mm_share_sync(&pmonitor->m_zlib, &pmonitor->m_zback);
361: }
1.1 provos 362: }
363:
364: int
1.11 mouring 365: monitor_read(struct monitor *pmonitor, struct mon_table *ent,
1.1 provos 366: struct mon_table **pent)
367: {
368: Buffer m;
369: int ret;
370: u_char type;
371:
372: buffer_init(&m);
373:
1.11 mouring 374: mm_request_receive(pmonitor->m_sendfd, &m);
1.1 provos 375: type = buffer_get_char(&m);
376:
1.14 markus 377: debug3("%s: checking request %d", __func__, type);
1.1 provos 378:
379: while (ent->f != NULL) {
380: if (ent->type == type)
381: break;
382: ent++;
383: }
384:
385: if (ent->f != NULL) {
386: if (!(ent->flags & MON_PERMIT))
1.14 markus 387: fatal("%s: unpermitted request %d", __func__,
1.1 provos 388: type);
1.11 mouring 389: ret = (*ent->f)(pmonitor->m_sendfd, &m);
1.1 provos 390: buffer_free(&m);
391:
392: /* The child may use this request only once, disable it */
393: if (ent->flags & MON_ONCE) {
1.14 markus 394: debug2("%s: %d used once, disabling now", __func__,
1.1 provos 395: type);
396: ent->flags &= ~MON_PERMIT;
397: }
398:
399: if (pent != NULL)
400: *pent = ent;
1.3 markus 401:
1.1 provos 402: return ret;
403: }
404:
1.14 markus 405: fatal("%s: unsupported request: %d", __func__, type);
1.1 provos 406:
407: /* NOTREACHED */
408: return (-1);
409: }
410:
411: /* allowed key state */
412: static int
413: monitor_allowed_key(u_char *blob, u_int bloblen)
414: {
415: /* make sure key is allowed */
416: if (key_blob == NULL || key_bloblen != bloblen ||
417: memcmp(key_blob, blob, key_bloblen))
418: return (0);
419: return (1);
420: }
421:
422: static void
423: monitor_reset_key_state(void)
424: {
425: /* reset state */
426: if (key_blob != NULL)
427: xfree(key_blob);
428: if (hostbased_cuser != NULL)
429: xfree(hostbased_cuser);
430: if (hostbased_chost != NULL)
431: xfree(hostbased_chost);
432: key_blob = NULL;
433: key_bloblen = 0;
434: key_blobtype = MM_NOKEY;
435: hostbased_cuser = NULL;
436: hostbased_chost = NULL;
437: }
438:
439: int
1.59 avsm 440: mm_answer_moduli(int sock, Buffer *m)
1.1 provos 441: {
442: DH *dh;
443: int min, want, max;
444:
445: min = buffer_get_int(m);
446: want = buffer_get_int(m);
447: max = buffer_get_int(m);
448:
449: debug3("%s: got parameters: %d %d %d",
1.14 markus 450: __func__, min, want, max);
1.1 provos 451: /* We need to check here, too, in case the child got corrupted */
452: if (max < min || want < min || max < want)
453: fatal("%s: bad parameters: %d %d %d",
1.14 markus 454: __func__, min, want, max);
1.1 provos 455:
456: buffer_clear(m);
457:
458: dh = choose_dh(min, want, max);
459: if (dh == NULL) {
460: buffer_put_char(m, 0);
461: return (0);
462: } else {
463: /* Send first bignum */
464: buffer_put_char(m, 1);
465: buffer_put_bignum2(m, dh->p);
466: buffer_put_bignum2(m, dh->g);
1.3 markus 467:
1.1 provos 468: DH_free(dh);
469: }
1.59 avsm 470: mm_request_send(sock, MONITOR_ANS_MODULI, m);
1.1 provos 471: return (0);
472: }
473:
474: int
1.59 avsm 475: mm_answer_sign(int sock, Buffer *m)
1.1 provos 476: {
477: Key *key;
478: u_char *p;
479: u_char *signature;
480: u_int siglen, datlen;
481: int keyid;
1.3 markus 482:
1.14 markus 483: debug3("%s", __func__);
1.1 provos 484:
1.3 markus 485: keyid = buffer_get_int(m);
486: p = buffer_get_string(m, &datlen);
1.1 provos 487:
1.69 djm 488: /*
1.71 deraadt 489: * Supported KEX types will only return SHA1 (20 byte) or
1.69 djm 490: * SHA256 (32 byte) hashes
491: */
492: if (datlen != 20 && datlen != 32)
1.19 deraadt 493: fatal("%s: data length incorrect: %u", __func__, datlen);
1.1 provos 494:
1.13 markus 495: /* save session id, it will be passed on the first call */
496: if (session_id2_len == 0) {
497: session_id2_len = datlen;
498: session_id2 = xmalloc(session_id2_len);
499: memcpy(session_id2, p, session_id2_len);
500: }
501:
1.1 provos 502: if ((key = get_hostkey_by_index(keyid)) == NULL)
1.14 markus 503: fatal("%s: no hostkey from index %d", __func__, keyid);
1.1 provos 504: if (key_sign(key, &signature, &siglen, p, datlen) < 0)
1.14 markus 505: fatal("%s: key_sign failed", __func__);
1.1 provos 506:
1.19 deraadt 507: debug3("%s: signature %p(%u)", __func__, signature, siglen);
1.1 provos 508:
509: buffer_clear(m);
510: buffer_put_string(m, signature, siglen);
511:
512: xfree(p);
513: xfree(signature);
514:
1.59 avsm 515: mm_request_send(sock, MONITOR_ANS_SIGN, m);
1.1 provos 516:
517: /* Turn on permissions for getpwnam */
518: monitor_permit(mon_dispatch, MONITOR_REQ_PWNAM, 1);
519:
520: return (0);
521: }
522:
523: /* Retrieves the password entry and also checks if the user is permitted */
524:
525: int
1.59 avsm 526: mm_answer_pwnamallow(int sock, Buffer *m)
1.1 provos 527: {
1.60 dtucker 528: char *username;
1.1 provos 529: struct passwd *pwent;
530: int allowed = 0;
1.3 markus 531:
1.14 markus 532: debug3("%s", __func__);
1.1 provos 533:
534: if (authctxt->attempt++ != 0)
1.14 markus 535: fatal("%s: multiple attempts for getpwnam", __func__);
1.1 provos 536:
1.60 dtucker 537: username = buffer_get_string(m, NULL);
1.1 provos 538:
1.60 dtucker 539: pwent = getpwnamallow(username);
1.1 provos 540:
1.60 dtucker 541: authctxt->user = xstrdup(username);
542: setproctitle("%s [priv]", pwent ? username : "unknown");
543: xfree(username);
1.1 provos 544:
545: buffer_clear(m);
546:
547: if (pwent == NULL) {
548: buffer_put_char(m, 0);
1.53 djm 549: authctxt->pw = fakepw();
1.1 provos 550: goto out;
551: }
552:
553: allowed = 1;
1.4 markus 554: authctxt->pw = pwent;
1.1 provos 555: authctxt->valid = 1;
556:
557: buffer_put_char(m, 1);
558: buffer_put_string(m, pwent, sizeof(struct passwd));
559: buffer_put_cstring(m, pwent->pw_name);
560: buffer_put_cstring(m, "*");
561: buffer_put_cstring(m, pwent->pw_gecos);
562: buffer_put_cstring(m, pwent->pw_class);
563: buffer_put_cstring(m, pwent->pw_dir);
564: buffer_put_cstring(m, pwent->pw_shell);
565:
566: out:
1.14 markus 567: debug3("%s: sending MONITOR_ANS_PWNAM: %d", __func__, allowed);
1.59 avsm 568: mm_request_send(sock, MONITOR_ANS_PWNAM, m);
1.1 provos 569:
570: /* For SSHv1 allow authentication now */
571: if (!compat20)
572: monitor_permit_authentications(1);
1.10 djm 573: else {
1.1 provos 574: /* Allow service/style information on the auth context */
575: monitor_permit(mon_dispatch, MONITOR_REQ_AUTHSERV, 1);
1.10 djm 576: monitor_permit(mon_dispatch, MONITOR_REQ_AUTH2_READ_BANNER, 1);
577: }
578:
579:
580: return (0);
581: }
582:
1.59 avsm 583: int mm_answer_auth2_read_banner(int sock, Buffer *m)
1.10 djm 584: {
585: char *banner;
586:
587: buffer_clear(m);
588: banner = auth2_read_banner();
589: buffer_put_cstring(m, banner != NULL ? banner : "");
1.59 avsm 590: mm_request_send(sock, MONITOR_ANS_AUTH2_READ_BANNER, m);
1.1 provos 591:
1.10 djm 592: if (banner != NULL)
1.21 deraadt 593: xfree(banner);
1.1 provos 594:
595: return (0);
596: }
597:
598: int
1.59 avsm 599: mm_answer_authserv(int sock, Buffer *m)
1.1 provos 600: {
601: monitor_permit_authentications(1);
602:
603: authctxt->service = buffer_get_string(m, NULL);
604: authctxt->style = buffer_get_string(m, NULL);
1.6 stevesk 605: debug3("%s: service=%s, style=%s",
1.14 markus 606: __func__, authctxt->service, authctxt->style);
1.6 stevesk 607:
1.1 provos 608: if (strlen(authctxt->style) == 0) {
609: xfree(authctxt->style);
610: authctxt->style = NULL;
611: }
612:
613: return (0);
614: }
615:
616: int
1.59 avsm 617: mm_answer_authpassword(int sock, Buffer *m)
1.1 provos 618: {
619: static int call_count;
620: char *passwd;
1.22 stevesk 621: int authenticated;
622: u_int plen;
1.1 provos 623:
624: passwd = buffer_get_string(m, &plen);
625: /* Only authenticate if the context is valid */
1.12 markus 626: authenticated = options.password_authentication &&
1.48 markus 627: auth_password(authctxt, passwd);
1.1 provos 628: memset(passwd, 0, strlen(passwd));
629: xfree(passwd);
630:
631: buffer_clear(m);
632: buffer_put_int(m, authenticated);
633:
1.14 markus 634: debug3("%s: sending result %d", __func__, authenticated);
1.59 avsm 635: mm_request_send(sock, MONITOR_ANS_AUTHPASSWORD, m);
1.1 provos 636:
637: call_count++;
638: if (plen == 0 && call_count == 1)
639: auth_method = "none";
640: else
641: auth_method = "password";
642:
643: /* Causes monitor loop to terminate if authenticated */
644: return (authenticated);
645: }
646:
647: #ifdef BSD_AUTH
648: int
1.59 avsm 649: mm_answer_bsdauthquery(int sock, Buffer *m)
1.1 provos 650: {
651: char *name, *infotxt;
652: u_int numprompts;
653: u_int *echo_on;
654: char **prompts;
1.31 markus 655: u_int success;
1.1 provos 656:
1.31 markus 657: success = bsdauth_query(authctxt, &name, &infotxt, &numprompts,
658: &prompts, &echo_on) < 0 ? 0 : 1;
1.1 provos 659:
660: buffer_clear(m);
1.31 markus 661: buffer_put_int(m, success);
662: if (success)
1.1 provos 663: buffer_put_cstring(m, prompts[0]);
664:
1.31 markus 665: debug3("%s: sending challenge success: %u", __func__, success);
1.59 avsm 666: mm_request_send(sock, MONITOR_ANS_BSDAUTHQUERY, m);
1.1 provos 667:
1.31 markus 668: if (success) {
1.1 provos 669: xfree(name);
670: xfree(infotxt);
671: xfree(prompts);
672: xfree(echo_on);
673: }
674:
675: return (0);
676: }
677:
678: int
1.59 avsm 679: mm_answer_bsdauthrespond(int sock, Buffer *m)
1.1 provos 680: {
681: char *response;
682: int authok;
683:
684: if (authctxt->as == 0)
1.14 markus 685: fatal("%s: no bsd auth session", __func__);
1.1 provos 686:
687: response = buffer_get_string(m, NULL);
1.12 markus 688: authok = options.challenge_response_authentication &&
689: auth_userresponse(authctxt->as, response, 0);
1.1 provos 690: authctxt->as = NULL;
1.14 markus 691: debug3("%s: <%s> = <%d>", __func__, response, authok);
1.1 provos 692: xfree(response);
693:
694: buffer_clear(m);
695: buffer_put_int(m, authok);
696:
1.14 markus 697: debug3("%s: sending authenticated: %d", __func__, authok);
1.59 avsm 698: mm_request_send(sock, MONITOR_ANS_BSDAUTHRESPOND, m);
1.1 provos 699:
700: auth_method = "bsdauth";
701:
702: return (authok != 0);
703: }
704: #endif
705:
706: #ifdef SKEY
707: int
1.59 avsm 708: mm_answer_skeyquery(int sock, Buffer *m)
1.1 provos 709: {
710: struct skey skey;
711: char challenge[1024];
1.31 markus 712: u_int success;
1.1 provos 713:
1.31 markus 714: success = skeychallenge(&skey, authctxt->user, challenge) < 0 ? 0 : 1;
1.1 provos 715:
716: buffer_clear(m);
1.31 markus 717: buffer_put_int(m, success);
718: if (success)
1.1 provos 719: buffer_put_cstring(m, challenge);
720:
1.31 markus 721: debug3("%s: sending challenge success: %u", __func__, success);
1.59 avsm 722: mm_request_send(sock, MONITOR_ANS_SKEYQUERY, m);
1.1 provos 723:
724: return (0);
725: }
726:
727: int
1.59 avsm 728: mm_answer_skeyrespond(int sock, Buffer *m)
1.1 provos 729: {
730: char *response;
731: int authok;
732:
733: response = buffer_get_string(m, NULL);
734:
1.12 markus 735: authok = (options.challenge_response_authentication &&
736: authctxt->valid &&
1.1 provos 737: skey_haskey(authctxt->pw->pw_name) == 0 &&
738: skey_passcheck(authctxt->pw->pw_name, response) != -1);
739:
740: xfree(response);
741:
742: buffer_clear(m);
743: buffer_put_int(m, authok);
744:
1.14 markus 745: debug3("%s: sending authenticated: %d", __func__, authok);
1.59 avsm 746: mm_request_send(sock, MONITOR_ANS_SKEYRESPOND, m);
1.1 provos 747:
748: auth_method = "skey";
749:
750: return (authok != 0);
751: }
752: #endif
753:
1.2 markus 754: static void
1.1 provos 755: mm_append_debug(Buffer *m)
756: {
757: if (auth_debug_init && buffer_len(&auth_debug)) {
1.14 markus 758: debug3("%s: Appending debug messages for child", __func__);
1.1 provos 759: buffer_append(m, buffer_ptr(&auth_debug),
760: buffer_len(&auth_debug));
761: buffer_clear(&auth_debug);
762: }
763: }
764:
765: int
1.59 avsm 766: mm_answer_keyallowed(int sock, Buffer *m)
1.1 provos 767: {
768: Key *key;
1.26 markus 769: char *cuser, *chost;
770: u_char *blob;
1.1 provos 771: u_int bloblen;
772: enum mm_keytype type = 0;
773: int allowed = 0;
774:
1.14 markus 775: debug3("%s entering", __func__);
1.3 markus 776:
1.1 provos 777: type = buffer_get_int(m);
778: cuser = buffer_get_string(m, NULL);
779: chost = buffer_get_string(m, NULL);
780: blob = buffer_get_string(m, &bloblen);
781:
782: key = key_from_blob(blob, bloblen);
783:
784: if ((compat20 && type == MM_RSAHOSTKEY) ||
785: (!compat20 && type != MM_RSAHOSTKEY))
1.14 markus 786: fatal("%s: key type and protocol mismatch", __func__);
1.1 provos 787:
1.14 markus 788: debug3("%s: key_from_blob: %p", __func__, key);
1.1 provos 789:
1.51 djm 790: if (key != NULL && authctxt->valid) {
1.63 deraadt 791: switch (type) {
1.1 provos 792: case MM_USERKEY:
1.12 markus 793: allowed = options.pubkey_authentication &&
794: user_key_allowed(authctxt->pw, key);
1.77 dtucker 795: auth_method = "publickey";
1.1 provos 796: break;
797: case MM_HOSTKEY:
1.12 markus 798: allowed = options.hostbased_authentication &&
799: hostbased_key_allowed(authctxt->pw,
1.1 provos 800: cuser, chost, key);
1.77 dtucker 801: auth_method = "hostbased";
1.1 provos 802: break;
803: case MM_RSAHOSTKEY:
804: key->type = KEY_RSA1; /* XXX */
1.12 markus 805: allowed = options.rhosts_rsa_authentication &&
806: auth_rhosts_rsa_key_allowed(authctxt->pw,
1.1 provos 807: cuser, chost, key);
1.77 dtucker 808: auth_method = "rsa";
1.1 provos 809: break;
810: default:
1.14 markus 811: fatal("%s: unknown key type %d", __func__, type);
1.1 provos 812: break;
813: }
1.33 markus 814: }
815: if (key != NULL)
1.1 provos 816: key_free(key);
817:
818: /* clear temporarily storage (used by verify) */
819: monitor_reset_key_state();
820:
821: if (allowed) {
822: /* Save temporarily for comparison in verify */
823: key_blob = blob;
824: key_bloblen = bloblen;
825: key_blobtype = type;
826: hostbased_cuser = cuser;
827: hostbased_chost = chost;
1.72 djm 828: } else {
1.77 dtucker 829: /* Log failed attempt */
830: auth_log(authctxt, 0, auth_method, compat20 ? " ssh2" : "");
1.72 djm 831: xfree(blob);
832: xfree(cuser);
833: xfree(chost);
1.1 provos 834: }
835:
836: debug3("%s: key %p is %s",
1.14 markus 837: __func__, key, allowed ? "allowed" : "disallowed");
1.1 provos 838:
839: buffer_clear(m);
840: buffer_put_int(m, allowed);
1.32 markus 841: buffer_put_int(m, forced_command != NULL);
1.1 provos 842:
843: mm_append_debug(m);
844:
1.59 avsm 845: mm_request_send(sock, MONITOR_ANS_KEYALLOWED, m);
1.1 provos 846:
847: if (type == MM_RSAHOSTKEY)
848: monitor_permit(mon_dispatch, MONITOR_REQ_RSACHALLENGE, allowed);
849:
850: return (0);
851: }
852:
853: static int
854: monitor_valid_userblob(u_char *data, u_int datalen)
855: {
856: Buffer b;
1.26 markus 857: char *p;
1.1 provos 858: u_int len;
859: int fail = 0;
860:
861: buffer_init(&b);
862: buffer_append(&b, data, datalen);
1.3 markus 863:
1.1 provos 864: if (datafellows & SSH_OLD_SESSIONID) {
1.13 markus 865: p = buffer_ptr(&b);
866: len = buffer_len(&b);
867: if ((session_id2 == NULL) ||
868: (len < session_id2_len) ||
869: (memcmp(p, session_id2, session_id2_len) != 0))
870: fail++;
1.1 provos 871: buffer_consume(&b, session_id2_len);
872: } else {
1.13 markus 873: p = buffer_get_string(&b, &len);
874: if ((session_id2 == NULL) ||
875: (len != session_id2_len) ||
876: (memcmp(p, session_id2, session_id2_len) != 0))
1.1 provos 877: fail++;
1.13 markus 878: xfree(p);
1.1 provos 879: }
880: if (buffer_get_char(&b) != SSH2_MSG_USERAUTH_REQUEST)
881: fail++;
882: p = buffer_get_string(&b, NULL);
883: if (strcmp(authctxt->user, p) != 0) {
1.38 itojun 884: logit("wrong user name passed to monitor: expected %s != %.100s",
1.1 provos 885: authctxt->user, p);
886: fail++;
887: }
888: xfree(p);
889: buffer_skip_string(&b);
890: if (datafellows & SSH_BUG_PKAUTH) {
891: if (!buffer_get_char(&b))
892: fail++;
893: } else {
894: p = buffer_get_string(&b, NULL);
895: if (strcmp("publickey", p) != 0)
896: fail++;
897: xfree(p);
898: if (!buffer_get_char(&b))
899: fail++;
900: buffer_skip_string(&b);
901: }
902: buffer_skip_string(&b);
903: if (buffer_len(&b) != 0)
904: fail++;
905: buffer_free(&b);
906: return (fail == 0);
907: }
908:
909: static int
1.26 markus 910: monitor_valid_hostbasedblob(u_char *data, u_int datalen, char *cuser,
911: char *chost)
1.1 provos 912: {
913: Buffer b;
1.26 markus 914: char *p;
1.1 provos 915: u_int len;
916: int fail = 0;
917:
918: buffer_init(&b);
919: buffer_append(&b, data, datalen);
1.3 markus 920:
1.13 markus 921: p = buffer_get_string(&b, &len);
922: if ((session_id2 == NULL) ||
923: (len != session_id2_len) ||
924: (memcmp(p, session_id2, session_id2_len) != 0))
1.1 provos 925: fail++;
1.13 markus 926: xfree(p);
927:
1.1 provos 928: if (buffer_get_char(&b) != SSH2_MSG_USERAUTH_REQUEST)
929: fail++;
930: p = buffer_get_string(&b, NULL);
931: if (strcmp(authctxt->user, p) != 0) {
1.38 itojun 932: logit("wrong user name passed to monitor: expected %s != %.100s",
1.1 provos 933: authctxt->user, p);
934: fail++;
935: }
936: xfree(p);
937: buffer_skip_string(&b); /* service */
938: p = buffer_get_string(&b, NULL);
939: if (strcmp(p, "hostbased") != 0)
940: fail++;
941: xfree(p);
942: buffer_skip_string(&b); /* pkalg */
943: buffer_skip_string(&b); /* pkblob */
944:
945: /* verify client host, strip trailing dot if necessary */
946: p = buffer_get_string(&b, NULL);
947: if (((len = strlen(p)) > 0) && p[len - 1] == '.')
948: p[len - 1] = '\0';
949: if (strcmp(p, chost) != 0)
950: fail++;
951: xfree(p);
952:
953: /* verify client user */
954: p = buffer_get_string(&b, NULL);
955: if (strcmp(p, cuser) != 0)
956: fail++;
957: xfree(p);
958:
959: if (buffer_len(&b) != 0)
960: fail++;
961: buffer_free(&b);
962: return (fail == 0);
963: }
964:
965: int
1.59 avsm 966: mm_answer_keyverify(int sock, Buffer *m)
1.1 provos 967: {
968: Key *key;
969: u_char *signature, *data, *blob;
970: u_int signaturelen, datalen, bloblen;
971: int verified = 0;
972: int valid_data = 0;
973:
974: blob = buffer_get_string(m, &bloblen);
975: signature = buffer_get_string(m, &signaturelen);
976: data = buffer_get_string(m, &datalen);
977:
978: if (hostbased_cuser == NULL || hostbased_chost == NULL ||
1.8 mouring 979: !monitor_allowed_key(blob, bloblen))
1.14 markus 980: fatal("%s: bad key, not previously allowed", __func__);
1.1 provos 981:
982: key = key_from_blob(blob, bloblen);
983: if (key == NULL)
1.14 markus 984: fatal("%s: bad public key blob", __func__);
1.1 provos 985:
986: switch (key_blobtype) {
987: case MM_USERKEY:
988: valid_data = monitor_valid_userblob(data, datalen);
989: break;
990: case MM_HOSTKEY:
991: valid_data = monitor_valid_hostbasedblob(data, datalen,
992: hostbased_cuser, hostbased_chost);
993: break;
994: default:
995: valid_data = 0;
996: break;
997: }
998: if (!valid_data)
1.14 markus 999: fatal("%s: bad signature data blob", __func__);
1.1 provos 1000:
1001: verified = key_verify(key, signature, signaturelen, data, datalen);
1002: debug3("%s: key %p signature %s",
1.14 markus 1003: __func__, key, verified ? "verified" : "unverified");
1.1 provos 1004:
1005: key_free(key);
1006: xfree(blob);
1007: xfree(signature);
1008: xfree(data);
1009:
1.17 stevesk 1010: auth_method = key_blobtype == MM_USERKEY ? "publickey" : "hostbased";
1011:
1.1 provos 1012: monitor_reset_key_state();
1.3 markus 1013:
1.1 provos 1014: buffer_clear(m);
1015: buffer_put_int(m, verified);
1.59 avsm 1016: mm_request_send(sock, MONITOR_ANS_KEYVERIFY, m);
1.1 provos 1017:
1018: return (verified);
1019: }
1020:
1.2 markus 1021: static void
1.1 provos 1022: mm_record_login(Session *s, struct passwd *pw)
1023: {
1024: socklen_t fromlen;
1025: struct sockaddr_storage from;
1026:
1027: /*
1028: * Get IP address of client. If the connection is not a socket, let
1029: * the address be 0.0.0.0.
1030: */
1031: memset(&from, 0, sizeof(from));
1.24 stevesk 1032: fromlen = sizeof(from);
1.1 provos 1033: if (packet_connection_is_on_socket()) {
1034: if (getpeername(packet_get_connection_in(),
1.74 deraadt 1035: (struct sockaddr *)&from, &fromlen) < 0) {
1.1 provos 1036: debug("getpeername: %.100s", strerror(errno));
1.50 markus 1037: cleanup_exit(255);
1.1 provos 1038: }
1039: }
1040: /* Record that there was a login on that tty from the remote host. */
1041: record_login(s->pid, s->tty, pw->pw_name, pw->pw_uid,
1.42 markus 1042: get_remote_name_or_ip(utmp_len, options.use_dns),
1.24 stevesk 1043: (struct sockaddr *)&from, fromlen);
1.1 provos 1044: }
1045:
1046: static void
1047: mm_session_close(Session *s)
1048: {
1.41 djm 1049: debug3("%s: session %d pid %ld", __func__, s->self, (long)s->pid);
1.1 provos 1050: if (s->ttyfd != -1) {
1.14 markus 1051: debug3("%s: tty %s ptyfd %d", __func__, s->tty, s->ptyfd);
1.1 provos 1052: session_pty_cleanup2(s);
1053: }
1054: s->used = 0;
1055: }
1056:
1057: int
1.59 avsm 1058: mm_answer_pty(int sock, Buffer *m)
1.1 provos 1059: {
1.11 mouring 1060: extern struct monitor *pmonitor;
1.1 provos 1061: Session *s;
1062: int res, fd0;
1063:
1.14 markus 1064: debug3("%s entering", __func__);
1.1 provos 1065:
1066: buffer_clear(m);
1067: s = session_new();
1068: if (s == NULL)
1069: goto error;
1070: s->authctxt = authctxt;
1071: s->pw = authctxt->pw;
1.11 mouring 1072: s->pid = pmonitor->m_pid;
1.1 provos 1073: res = pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty));
1074: if (res == 0)
1075: goto error;
1076: pty_setowner(authctxt->pw, s->tty);
1077:
1078: buffer_put_int(m, 1);
1079: buffer_put_cstring(m, s->tty);
1080:
1081: /* We need to trick ttyslot */
1082: if (dup2(s->ttyfd, 0) == -1)
1.14 markus 1083: fatal("%s: dup2", __func__);
1.1 provos 1084:
1085: mm_record_login(s, authctxt->pw);
1086:
1087: /* Now we can close the file descriptor again */
1088: close(0);
1.61 dtucker 1089:
1090: /* send messages generated by record_login */
1091: buffer_put_string(m, buffer_ptr(&loginmsg), buffer_len(&loginmsg));
1092: buffer_clear(&loginmsg);
1093:
1094: mm_request_send(sock, MONITOR_ANS_PTY, m);
1095:
1096: mm_send_fd(sock, s->ptyfd);
1097: mm_send_fd(sock, s->ttyfd);
1.1 provos 1098:
1099: /* make sure nothing uses fd 0 */
1100: if ((fd0 = open(_PATH_DEVNULL, O_RDONLY)) < 0)
1.14 markus 1101: fatal("%s: open(/dev/null): %s", __func__, strerror(errno));
1.1 provos 1102: if (fd0 != 0)
1.14 markus 1103: error("%s: fd0 %d != 0", __func__, fd0);
1.1 provos 1104:
1105: /* slave is not needed */
1106: close(s->ttyfd);
1107: s->ttyfd = s->ptyfd;
1108: /* no need to dup() because nobody closes ptyfd */
1109: s->ptymaster = s->ptyfd;
1110:
1.14 markus 1111: debug3("%s: tty %s ptyfd %d", __func__, s->tty, s->ttyfd);
1.1 provos 1112:
1113: return (0);
1114:
1115: error:
1116: if (s != NULL)
1117: mm_session_close(s);
1118: buffer_put_int(m, 0);
1.59 avsm 1119: mm_request_send(sock, MONITOR_ANS_PTY, m);
1.1 provos 1120: return (0);
1121: }
1122:
1123: int
1.59 avsm 1124: mm_answer_pty_cleanup(int sock, Buffer *m)
1.1 provos 1125: {
1126: Session *s;
1127: char *tty;
1128:
1.14 markus 1129: debug3("%s entering", __func__);
1.1 provos 1130:
1131: tty = buffer_get_string(m, NULL);
1132: if ((s = session_by_tty(tty)) != NULL)
1133: mm_session_close(s);
1134: buffer_clear(m);
1135: xfree(tty);
1136: return (0);
1137: }
1138:
1139: int
1.59 avsm 1140: mm_answer_sesskey(int sock, Buffer *m)
1.1 provos 1141: {
1142: BIGNUM *p;
1143: int rsafail;
1144:
1145: /* Turn off permissions */
1.62 dtucker 1146: monitor_permit(mon_dispatch, MONITOR_REQ_SESSKEY, 0);
1.1 provos 1147:
1148: if ((p = BN_new()) == NULL)
1.14 markus 1149: fatal("%s: BN_new", __func__);
1.1 provos 1150:
1151: buffer_get_bignum2(m, p);
1152:
1153: rsafail = ssh1_session_key(p);
1154:
1155: buffer_clear(m);
1156: buffer_put_int(m, rsafail);
1157: buffer_put_bignum2(m, p);
1158:
1159: BN_clear_free(p);
1160:
1.59 avsm 1161: mm_request_send(sock, MONITOR_ANS_SESSKEY, m);
1.1 provos 1162:
1163: /* Turn on permissions for sessid passing */
1164: monitor_permit(mon_dispatch, MONITOR_REQ_SESSID, 1);
1165:
1166: return (0);
1167: }
1168:
1169: int
1.59 avsm 1170: mm_answer_sessid(int sock, Buffer *m)
1.1 provos 1171: {
1172: int i;
1173:
1.14 markus 1174: debug3("%s entering", __func__);
1.1 provos 1175:
1176: if (buffer_len(m) != 16)
1.14 markus 1177: fatal("%s: bad ssh1 session id", __func__);
1.1 provos 1178: for (i = 0; i < 16; i++)
1179: session_id[i] = buffer_get_char(m);
1180:
1181: /* Turn on permissions for getpwnam */
1182: monitor_permit(mon_dispatch, MONITOR_REQ_PWNAM, 1);
1183:
1184: return (0);
1185: }
1186:
1187: int
1.59 avsm 1188: mm_answer_rsa_keyallowed(int sock, Buffer *m)
1.1 provos 1189: {
1190: BIGNUM *client_n;
1191: Key *key = NULL;
1.3 markus 1192: u_char *blob = NULL;
1193: u_int blen = 0;
1.1 provos 1194: int allowed = 0;
1195:
1.14 markus 1196: debug3("%s entering", __func__);
1.1 provos 1197:
1.77 dtucker 1198: auth_method = "rsa";
1.12 markus 1199: if (options.rsa_authentication && authctxt->valid) {
1.1 provos 1200: if ((client_n = BN_new()) == NULL)
1.14 markus 1201: fatal("%s: BN_new", __func__);
1.1 provos 1202: buffer_get_bignum2(m, client_n);
1203: allowed = auth_rsa_key_allowed(authctxt->pw, client_n, &key);
1204: BN_clear_free(client_n);
1205: }
1206: buffer_clear(m);
1207: buffer_put_int(m, allowed);
1.32 markus 1208: buffer_put_int(m, forced_command != NULL);
1.1 provos 1209:
1210: /* clear temporarily storage (used by generate challenge) */
1211: monitor_reset_key_state();
1212:
1213: if (allowed && key != NULL) {
1214: key->type = KEY_RSA; /* cheat for key_to_blob */
1215: if (key_to_blob(key, &blob, &blen) == 0)
1.14 markus 1216: fatal("%s: key_to_blob failed", __func__);
1.1 provos 1217: buffer_put_string(m, blob, blen);
1218:
1219: /* Save temporarily for comparison in verify */
1220: key_blob = blob;
1221: key_bloblen = blen;
1222: key_blobtype = MM_RSAUSERKEY;
1.33 markus 1223: }
1224: if (key != NULL)
1.1 provos 1225: key_free(key);
1226:
1227: mm_append_debug(m);
1228:
1.59 avsm 1229: mm_request_send(sock, MONITOR_ANS_RSAKEYALLOWED, m);
1.1 provos 1230:
1231: monitor_permit(mon_dispatch, MONITOR_REQ_RSACHALLENGE, allowed);
1232: monitor_permit(mon_dispatch, MONITOR_REQ_RSARESPONSE, 0);
1233: return (0);
1234: }
1235:
1236: int
1.59 avsm 1237: mm_answer_rsa_challenge(int sock, Buffer *m)
1.1 provos 1238: {
1239: Key *key = NULL;
1.3 markus 1240: u_char *blob;
1241: u_int blen;
1.1 provos 1242:
1.14 markus 1243: debug3("%s entering", __func__);
1.1 provos 1244:
1245: if (!authctxt->valid)
1.14 markus 1246: fatal("%s: authctxt not valid", __func__);
1.1 provos 1247: blob = buffer_get_string(m, &blen);
1248: if (!monitor_allowed_key(blob, blen))
1.14 markus 1249: fatal("%s: bad key, not previously allowed", __func__);
1.1 provos 1250: if (key_blobtype != MM_RSAUSERKEY && key_blobtype != MM_RSAHOSTKEY)
1.14 markus 1251: fatal("%s: key type mismatch", __func__);
1.1 provos 1252: if ((key = key_from_blob(blob, blen)) == NULL)
1.14 markus 1253: fatal("%s: received bad key", __func__);
1.1 provos 1254:
1255: if (ssh1_challenge)
1256: BN_clear_free(ssh1_challenge);
1257: ssh1_challenge = auth_rsa_generate_challenge(key);
1258:
1259: buffer_clear(m);
1260: buffer_put_bignum2(m, ssh1_challenge);
1261:
1.14 markus 1262: debug3("%s sending reply", __func__);
1.59 avsm 1263: mm_request_send(sock, MONITOR_ANS_RSACHALLENGE, m);
1.1 provos 1264:
1265: monitor_permit(mon_dispatch, MONITOR_REQ_RSARESPONSE, 1);
1.33 markus 1266:
1267: xfree(blob);
1268: key_free(key);
1.1 provos 1269: return (0);
1270: }
1271:
1272: int
1.59 avsm 1273: mm_answer_rsa_response(int sock, Buffer *m)
1.1 provos 1274: {
1275: Key *key = NULL;
1.3 markus 1276: u_char *blob, *response;
1277: u_int blen, len;
1278: int success;
1.1 provos 1279:
1.14 markus 1280: debug3("%s entering", __func__);
1.1 provos 1281:
1282: if (!authctxt->valid)
1.14 markus 1283: fatal("%s: authctxt not valid", __func__);
1.1 provos 1284: if (ssh1_challenge == NULL)
1.14 markus 1285: fatal("%s: no ssh1_challenge", __func__);
1.1 provos 1286:
1287: blob = buffer_get_string(m, &blen);
1288: if (!monitor_allowed_key(blob, blen))
1.14 markus 1289: fatal("%s: bad key, not previously allowed", __func__);
1.1 provos 1290: if (key_blobtype != MM_RSAUSERKEY && key_blobtype != MM_RSAHOSTKEY)
1.14 markus 1291: fatal("%s: key type mismatch: %d", __func__, key_blobtype);
1.1 provos 1292: if ((key = key_from_blob(blob, blen)) == NULL)
1.14 markus 1293: fatal("%s: received bad key", __func__);
1.1 provos 1294: response = buffer_get_string(m, &len);
1295: if (len != 16)
1.14 markus 1296: fatal("%s: received bad response to challenge", __func__);
1.1 provos 1297: success = auth_rsa_verify_response(key, ssh1_challenge, response);
1298:
1.33 markus 1299: xfree(blob);
1.1 provos 1300: key_free(key);
1301: xfree(response);
1302:
1303: auth_method = key_blobtype == MM_RSAUSERKEY ? "rsa" : "rhosts-rsa";
1304:
1305: /* reset state */
1306: BN_clear_free(ssh1_challenge);
1307: ssh1_challenge = NULL;
1308: monitor_reset_key_state();
1309:
1310: buffer_clear(m);
1311: buffer_put_int(m, success);
1.59 avsm 1312: mm_request_send(sock, MONITOR_ANS_RSARESPONSE, m);
1.1 provos 1313:
1314: return (success);
1315: }
1316:
1317: int
1.59 avsm 1318: mm_answer_term(int sock, Buffer *req)
1.1 provos 1319: {
1.11 mouring 1320: extern struct monitor *pmonitor;
1.1 provos 1321: int res, status;
1322:
1.14 markus 1323: debug3("%s: tearing down sessions", __func__);
1.1 provos 1324:
1325: /* The child is terminating */
1326: session_destroy_all(&mm_session_close);
1327:
1.11 mouring 1328: while (waitpid(pmonitor->m_pid, &status, 0) == -1)
1.9 markus 1329: if (errno != EINTR)
1330: exit(1);
1.1 provos 1331:
1332: res = WIFEXITED(status) ? WEXITSTATUS(status) : 1;
1333:
1334: /* Terminate process */
1.57 deraadt 1335: exit(res);
1.1 provos 1336: }
1337:
1338: void
1.11 mouring 1339: monitor_apply_keystate(struct monitor *pmonitor)
1.1 provos 1340: {
1341: if (compat20) {
1342: set_newkeys(MODE_IN);
1343: set_newkeys(MODE_OUT);
1344: } else {
1345: packet_set_protocol_flags(child_state.ssh1protoflags);
1.15 markus 1346: packet_set_encryption_key(child_state.ssh1key,
1347: child_state.ssh1keylen, child_state.ssh1cipher);
1348: xfree(child_state.ssh1key);
1.1 provos 1349: }
1350:
1.15 markus 1351: /* for rc4 and other stateful ciphers */
1.1 provos 1352: packet_set_keycontext(MODE_OUT, child_state.keyout);
1353: xfree(child_state.keyout);
1354: packet_set_keycontext(MODE_IN, child_state.keyin);
1355: xfree(child_state.keyin);
1356:
1357: if (!compat20) {
1358: packet_set_iv(MODE_OUT, child_state.ivout);
1359: xfree(child_state.ivout);
1360: packet_set_iv(MODE_IN, child_state.ivin);
1361: xfree(child_state.ivin);
1362: }
1363:
1364: memcpy(&incoming_stream, &child_state.incoming,
1365: sizeof(incoming_stream));
1366: memcpy(&outgoing_stream, &child_state.outgoing,
1367: sizeof(outgoing_stream));
1.3 markus 1368:
1.1 provos 1369: /* Update with new address */
1.16 djm 1370: if (options.compression)
1371: mm_init_compression(pmonitor->m_zlib);
1.1 provos 1372:
1373: /* Network I/O buffers */
1374: /* XXX inefficient for large buffers, need: buffer_init_from_string */
1375: buffer_clear(&input);
1376: buffer_append(&input, child_state.input, child_state.ilen);
1377: memset(child_state.input, 0, child_state.ilen);
1378: xfree(child_state.input);
1379:
1380: buffer_clear(&output);
1381: buffer_append(&output, child_state.output, child_state.olen);
1382: memset(child_state.output, 0, child_state.olen);
1383: xfree(child_state.output);
1384: }
1385:
1.2 markus 1386: static Kex *
1.1 provos 1387: mm_get_kex(Buffer *m)
1388: {
1389: Kex *kex;
1390: void *blob;
1391: u_int bloblen;
1392:
1.75 djm 1393: kex = xcalloc(1, sizeof(*kex));
1.1 provos 1394: kex->session_id = buffer_get_string(m, &kex->session_id_len);
1.13 markus 1395: if ((session_id2 == NULL) ||
1396: (kex->session_id_len != session_id2_len) ||
1397: (memcmp(kex->session_id, session_id2, session_id2_len) != 0))
1398: fatal("mm_get_get: internal error: bad session id");
1.1 provos 1399: kex->we_need = buffer_get_int(m);
1.34 markus 1400: kex->kex[KEX_DH_GRP1_SHA1] = kexdh_server;
1.58 djm 1401: kex->kex[KEX_DH_GRP14_SHA1] = kexdh_server;
1.34 markus 1402: kex->kex[KEX_DH_GEX_SHA1] = kexgex_server;
1.69 djm 1403: kex->kex[KEX_DH_GEX_SHA256] = kexgex_server;
1.1 provos 1404: kex->server = 1;
1405: kex->hostkey_type = buffer_get_int(m);
1406: kex->kex_type = buffer_get_int(m);
1407: blob = buffer_get_string(m, &bloblen);
1408: buffer_init(&kex->my);
1409: buffer_append(&kex->my, blob, bloblen);
1410: xfree(blob);
1411: blob = buffer_get_string(m, &bloblen);
1412: buffer_init(&kex->peer);
1413: buffer_append(&kex->peer, blob, bloblen);
1414: xfree(blob);
1415: kex->done = 1;
1416: kex->flags = buffer_get_int(m);
1417: kex->client_version_string = buffer_get_string(m, NULL);
1418: kex->server_version_string = buffer_get_string(m, NULL);
1419: kex->load_host_key=&get_hostkey_by_type;
1420: kex->host_key_index=&get_hostkey_index;
1421:
1422: return (kex);
1423: }
1424:
1425: /* This function requries careful sanity checking */
1426:
1427: void
1.11 mouring 1428: mm_get_keystate(struct monitor *pmonitor)
1.1 provos 1429: {
1430: Buffer m;
1431: u_char *blob, *p;
1432: u_int bloblen, plen;
1.37 markus 1433: u_int32_t seqnr, packets;
1434: u_int64_t blocks;
1.1 provos 1435:
1.14 markus 1436: debug3("%s: Waiting for new keys", __func__);
1.1 provos 1437:
1438: buffer_init(&m);
1.11 mouring 1439: mm_request_receive_expect(pmonitor->m_sendfd, MONITOR_REQ_KEYEXPORT, &m);
1.1 provos 1440: if (!compat20) {
1441: child_state.ssh1protoflags = buffer_get_int(&m);
1442: child_state.ssh1cipher = buffer_get_int(&m);
1.15 markus 1443: child_state.ssh1key = buffer_get_string(&m,
1444: &child_state.ssh1keylen);
1.1 provos 1445: child_state.ivout = buffer_get_string(&m,
1446: &child_state.ivoutlen);
1447: child_state.ivin = buffer_get_string(&m, &child_state.ivinlen);
1448: goto skip;
1449: } else {
1450: /* Get the Kex for rekeying */
1.11 mouring 1451: *pmonitor->m_pkex = mm_get_kex(&m);
1.1 provos 1452: }
1453:
1454: blob = buffer_get_string(&m, &bloblen);
1455: current_keys[MODE_OUT] = mm_newkeys_from_blob(blob, bloblen);
1456: xfree(blob);
1457:
1.14 markus 1458: debug3("%s: Waiting for second key", __func__);
1.1 provos 1459: blob = buffer_get_string(&m, &bloblen);
1460: current_keys[MODE_IN] = mm_newkeys_from_blob(blob, bloblen);
1461: xfree(blob);
1.3 markus 1462:
1.1 provos 1463: /* Now get sequence numbers for the packets */
1.37 markus 1464: seqnr = buffer_get_int(&m);
1465: blocks = buffer_get_int64(&m);
1466: packets = buffer_get_int(&m);
1467: packet_set_state(MODE_OUT, seqnr, blocks, packets);
1468: seqnr = buffer_get_int(&m);
1469: blocks = buffer_get_int64(&m);
1470: packets = buffer_get_int(&m);
1471: packet_set_state(MODE_IN, seqnr, blocks, packets);
1.1 provos 1472:
1473: skip:
1474: /* Get the key context */
1475: child_state.keyout = buffer_get_string(&m, &child_state.keyoutlen);
1476: child_state.keyin = buffer_get_string(&m, &child_state.keyinlen);
1477:
1.14 markus 1478: debug3("%s: Getting compression state", __func__);
1.1 provos 1479: /* Get compression state */
1480: p = buffer_get_string(&m, &plen);
1481: if (plen != sizeof(child_state.outgoing))
1.14 markus 1482: fatal("%s: bad request size", __func__);
1.1 provos 1483: memcpy(&child_state.outgoing, p, sizeof(child_state.outgoing));
1484: xfree(p);
1485:
1486: p = buffer_get_string(&m, &plen);
1487: if (plen != sizeof(child_state.incoming))
1.14 markus 1488: fatal("%s: bad request size", __func__);
1.1 provos 1489: memcpy(&child_state.incoming, p, sizeof(child_state.incoming));
1490: xfree(p);
1491:
1492: /* Network I/O buffers */
1.14 markus 1493: debug3("%s: Getting Network I/O buffers", __func__);
1.1 provos 1494: child_state.input = buffer_get_string(&m, &child_state.ilen);
1495: child_state.output = buffer_get_string(&m, &child_state.olen);
1496:
1497: buffer_free(&m);
1498: }
1499:
1500:
1501: /* Allocation functions for zlib */
1502: void *
1503: mm_zalloc(struct mm_master *mm, u_int ncount, u_int size)
1504: {
1.30 markus 1505: size_t len = (size_t) size * ncount;
1.1 provos 1506: void *address;
1507:
1.23 millert 1508: if (len == 0 || ncount > SIZE_T_MAX / size)
1.18 deraadt 1509: fatal("%s: mm_zalloc(%u, %u)", __func__, ncount, size);
1510:
1511: address = mm_malloc(mm, len);
1.1 provos 1512:
1513: return (address);
1514: }
1515:
1516: void
1517: mm_zfree(struct mm_master *mm, void *address)
1518: {
1519: mm_free(mm, address);
1520: }
1521:
1522: void
1523: mm_init_compression(struct mm_master *mm)
1524: {
1525: outgoing_stream.zalloc = (alloc_func)mm_zalloc;
1526: outgoing_stream.zfree = (free_func)mm_zfree;
1527: outgoing_stream.opaque = mm;
1528:
1529: incoming_stream.zalloc = (alloc_func)mm_zalloc;
1530: incoming_stream.zfree = (free_func)mm_zfree;
1531: incoming_stream.opaque = mm;
1532: }
1533:
1534: /* XXX */
1535:
1536: #define FD_CLOSEONEXEC(x) do { \
1537: if (fcntl(x, F_SETFD, 1) == -1) \
1538: fatal("fcntl(%d, F_SETFD)", x); \
1539: } while (0)
1540:
1.2 markus 1541: static void
1.1 provos 1542: monitor_socketpair(int *pair)
1.3 markus 1543: {
1.1 provos 1544: if (socketpair(AF_UNIX, SOCK_STREAM, 0, pair) == -1)
1.14 markus 1545: fatal("%s: socketpair", __func__);
1.1 provos 1546: FD_CLOSEONEXEC(pair[0]);
1547: FD_CLOSEONEXEC(pair[1]);
1548: }
1549:
1550: #define MM_MEMSIZE 65536
1551:
1552: struct monitor *
1553: monitor_init(void)
1554: {
1555: struct monitor *mon;
1556: int pair[2];
1557:
1.75 djm 1558: mon = xcalloc(1, sizeof(*mon));
1.1 provos 1559:
1560: monitor_socketpair(pair);
1561:
1562: mon->m_recvfd = pair[0];
1563: mon->m_sendfd = pair[1];
1564:
1565: /* Used to share zlib space across processes */
1.16 djm 1566: if (options.compression) {
1567: mon->m_zback = mm_create(NULL, MM_MEMSIZE);
1568: mon->m_zlib = mm_create(mon->m_zback, 20 * MM_MEMSIZE);
1.1 provos 1569:
1.16 djm 1570: /* Compression needs to share state across borders */
1571: mm_init_compression(mon->m_zlib);
1572: }
1.1 provos 1573:
1574: return mon;
1575: }
1576:
1577: void
1578: monitor_reinit(struct monitor *mon)
1579: {
1580: int pair[2];
1581:
1582: monitor_socketpair(pair);
1583:
1584: mon->m_recvfd = pair[0];
1585: mon->m_sendfd = pair[1];
1586: }
1.46 markus 1587:
1588: #ifdef GSSAPI
1589: int
1.59 avsm 1590: mm_answer_gss_setup_ctx(int sock, Buffer *m)
1.46 markus 1591: {
1.59 avsm 1592: gss_OID_desc goid;
1.46 markus 1593: OM_uint32 major;
1594: u_int len;
1595:
1.59 avsm 1596: goid.elements = buffer_get_string(m, &len);
1597: goid.length = len;
1.46 markus 1598:
1.59 avsm 1599: major = ssh_gssapi_server_ctx(&gsscontext, &goid);
1.46 markus 1600:
1.59 avsm 1601: xfree(goid.elements);
1.46 markus 1602:
1603: buffer_clear(m);
1604: buffer_put_int(m, major);
1605:
1.64 stevesk 1606: mm_request_send(sock, MONITOR_ANS_GSSSETUP, m);
1.46 markus 1607:
1608: /* Now we have a context, enable the step */
1609: monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 1);
1610:
1611: return (0);
1612: }
1613:
1614: int
1.59 avsm 1615: mm_answer_gss_accept_ctx(int sock, Buffer *m)
1.46 markus 1616: {
1617: gss_buffer_desc in;
1618: gss_buffer_desc out = GSS_C_EMPTY_BUFFER;
1.64 stevesk 1619: OM_uint32 major, minor;
1.46 markus 1620: OM_uint32 flags = 0; /* GSI needs this */
1.47 deraadt 1621: u_int len;
1.46 markus 1622:
1.47 deraadt 1623: in.value = buffer_get_string(m, &len);
1624: in.length = len;
1.46 markus 1625: major = ssh_gssapi_accept_ctx(gsscontext, &in, &out, &flags);
1626: xfree(in.value);
1627:
1628: buffer_clear(m);
1629: buffer_put_int(m, major);
1630: buffer_put_string(m, out.value, out.length);
1631: buffer_put_int(m, flags);
1.59 avsm 1632: mm_request_send(sock, MONITOR_ANS_GSSSTEP, m);
1.46 markus 1633:
1634: gss_release_buffer(&minor, &out);
1635:
1.64 stevesk 1636: if (major == GSS_S_COMPLETE) {
1.46 markus 1637: monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 0);
1638: monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
1.52 markus 1639: monitor_permit(mon_dispatch, MONITOR_REQ_GSSCHECKMIC, 1);
1.46 markus 1640: }
1641: return (0);
1642: }
1643:
1644: int
1.59 avsm 1645: mm_answer_gss_checkmic(int sock, Buffer *m)
1.52 markus 1646: {
1647: gss_buffer_desc gssbuf, mic;
1648: OM_uint32 ret;
1649: u_int len;
1.54 djm 1650:
1.52 markus 1651: gssbuf.value = buffer_get_string(m, &len);
1652: gssbuf.length = len;
1653: mic.value = buffer_get_string(m, &len);
1654: mic.length = len;
1.54 djm 1655:
1.52 markus 1656: ret = ssh_gssapi_checkmic(gsscontext, &gssbuf, &mic);
1.54 djm 1657:
1.52 markus 1658: xfree(gssbuf.value);
1659: xfree(mic.value);
1.54 djm 1660:
1.52 markus 1661: buffer_clear(m);
1662: buffer_put_int(m, ret);
1.54 djm 1663:
1.59 avsm 1664: mm_request_send(sock, MONITOR_ANS_GSSCHECKMIC, m);
1.54 djm 1665:
1.52 markus 1666: if (!GSS_ERROR(ret))
1667: monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
1.54 djm 1668:
1.52 markus 1669: return (0);
1670: }
1671:
1672: int
1.59 avsm 1673: mm_answer_gss_userok(int sock, Buffer *m)
1.46 markus 1674: {
1675: int authenticated;
1676:
1677: authenticated = authctxt->valid && ssh_gssapi_userok(authctxt->user);
1678:
1679: buffer_clear(m);
1680: buffer_put_int(m, authenticated);
1681:
1682: debug3("%s: sending result %d", __func__, authenticated);
1.59 avsm 1683: mm_request_send(sock, MONITOR_ANS_GSSUSEROK, m);
1.46 markus 1684:
1.64 stevesk 1685: auth_method = "gssapi-with-mic";
1.46 markus 1686:
1687: /* Monitor loop will terminate if authenticated */
1688: return (authenticated);
1689: }
1690: #endif /* GSSAPI */
![[BACK]](/icons/back.gif){kind=icon}
Return to monitor.c CVS log ![[TXT]](/icons/text.gif){kind=icon}
![[DIR]](/icons/dir.gif){kind=icon}
Up to [local] / src / usr.bin / ssh