Annotation of src/usr.bin/ssh/monitor.c, Revision 1.94
1.94 ! dtucker 1: /* $OpenBSD: monitor.c,v 1.93 2007/09/21 08:15:29 djm 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:
1.67 stevesk 28: #include <sys/types.h>
29: #include <sys/wait.h>
1.79 stevesk 30: #include <sys/socket.h>
1.85 deraadt 31: #include <sys/tree.h>
1.83 stevesk 32: #include <sys/param.h>
1.1 provos 33:
1.78 stevesk 34: #include <openssl/dh.h>
35:
1.81 stevesk 36: #include <errno.h>
1.80 stevesk 37: #include <fcntl.h>
1.65 stevesk 38: #include <paths.h>
1.78 stevesk 39: #include <pwd.h>
1.68 stevesk 40: #include <signal.h>
1.84 stevesk 41: #include <stdlib.h>
1.82 stevesk 42: #include <string.h>
1.1 provos 43:
44:
1.85 deraadt 45: #include "xmalloc.h"
1.1 provos 46: #include "ssh.h"
1.85 deraadt 47: #include "key.h"
48: #include "buffer.h"
49: #include "hostfile.h"
1.1 provos 50: #include "auth.h"
1.85 deraadt 51: #include "cipher.h"
1.1 provos 52: #include "kex.h"
53: #include "dh.h"
1.88 miod 54: #include <zlib.h>
1.1 provos 55: #include "packet.h"
56: #include "auth-options.h"
57: #include "sshpty.h"
58: #include "channels.h"
59: #include "session.h"
60: #include "sshlogin.h"
61: #include "canohost.h"
62: #include "log.h"
63: #include "servconf.h"
64: #include "monitor.h"
65: #include "monitor_mm.h"
1.85 deraadt 66: #ifdef GSSAPI
67: #include "ssh-gss.h"
68: #endif
1.1 provos 69: #include "monitor_wrap.h"
70: #include "monitor_fdpass.h"
71: #include "misc.h"
72: #include "compat.h"
73: #include "ssh2.h"
74:
1.46 markus 75: #ifdef GSSAPI
76: static Gssctxt *gsscontext = NULL;
77: #endif
78:
1.1 provos 79: /* Imports */
80: extern ServerOptions options;
81: extern u_int utmp_len;
82: extern Newkeys *current_keys[];
83: extern z_stream incoming_stream;
84: extern z_stream outgoing_stream;
85: extern u_char session_id[];
86: extern Buffer input, output;
87: extern Buffer auth_debug;
88: extern int auth_debug_init;
1.61 dtucker 89: extern Buffer loginmsg;
1.1 provos 90:
91: /* State exported from the child */
92:
93: struct {
94: z_stream incoming;
95: z_stream outgoing;
96: u_char *keyin;
97: u_int keyinlen;
98: u_char *keyout;
99: u_int keyoutlen;
100: u_char *ivin;
101: u_int ivinlen;
102: u_char *ivout;
103: u_int ivoutlen;
1.15 markus 104: u_char *ssh1key;
105: u_int ssh1keylen;
1.1 provos 106: int ssh1cipher;
107: int ssh1protoflags;
108: u_char *input;
109: u_int ilen;
110: u_char *output;
111: u_int olen;
112: } child_state;
113:
1.43 markus 114: /* Functions on the monitor that answer unprivileged requests */
1.1 provos 115:
116: int mm_answer_moduli(int, Buffer *);
117: int mm_answer_sign(int, Buffer *);
118: int mm_answer_pwnamallow(int, Buffer *);
1.10 djm 119: int mm_answer_auth2_read_banner(int, Buffer *);
1.1 provos 120: int mm_answer_authserv(int, Buffer *);
121: int mm_answer_authpassword(int, Buffer *);
122: int mm_answer_bsdauthquery(int, Buffer *);
123: int mm_answer_bsdauthrespond(int, Buffer *);
124: int mm_answer_skeyquery(int, Buffer *);
125: int mm_answer_skeyrespond(int, Buffer *);
126: int mm_answer_keyallowed(int, Buffer *);
127: int mm_answer_keyverify(int, Buffer *);
128: int mm_answer_pty(int, Buffer *);
129: int mm_answer_pty_cleanup(int, Buffer *);
130: int mm_answer_term(int, Buffer *);
131: int mm_answer_rsa_keyallowed(int, Buffer *);
132: int mm_answer_rsa_challenge(int, Buffer *);
133: int mm_answer_rsa_response(int, Buffer *);
134: int mm_answer_sesskey(int, Buffer *);
135: int mm_answer_sessid(int, Buffer *);
136:
1.46 markus 137: #ifdef GSSAPI
138: int mm_answer_gss_setup_ctx(int, Buffer *);
139: int mm_answer_gss_accept_ctx(int, Buffer *);
140: int mm_answer_gss_userok(int, Buffer *);
1.52 markus 141: int mm_answer_gss_checkmic(int, Buffer *);
1.46 markus 142: #endif
1.25 itojun 143:
1.1 provos 144: static Authctxt *authctxt;
145: static BIGNUM *ssh1_challenge = NULL; /* used for ssh1 rsa auth */
146:
147: /* local state for key verify */
148: static u_char *key_blob = NULL;
149: static u_int key_bloblen = 0;
150: static int key_blobtype = MM_NOKEY;
1.26 markus 151: static char *hostbased_cuser = NULL;
152: static char *hostbased_chost = NULL;
1.1 provos 153: static char *auth_method = "unknown";
1.44 markus 154: static u_int session_id2_len = 0;
1.13 markus 155: static u_char *session_id2 = NULL;
1.40 markus 156: static pid_t monitor_child_pid;
1.1 provos 157:
158: struct mon_table {
159: enum monitor_reqtype type;
160: int flags;
161: int (*f)(int, Buffer *);
162: };
163:
164: #define MON_ISAUTH 0x0004 /* Required for Authentication */
165: #define MON_AUTHDECIDE 0x0008 /* Decides Authentication */
166: #define MON_ONCE 0x0010 /* Disable after calling */
1.77 dtucker 167: #define MON_ALOG 0x0020 /* Log auth attempt without authenticating */
1.1 provos 168:
169: #define MON_AUTH (MON_ISAUTH|MON_AUTHDECIDE)
170:
171: #define MON_PERMIT 0x1000 /* Request is permitted */
172:
173: struct mon_table mon_dispatch_proto20[] = {
174: {MONITOR_REQ_MODULI, MON_ONCE, mm_answer_moduli},
175: {MONITOR_REQ_SIGN, MON_ONCE, mm_answer_sign},
176: {MONITOR_REQ_PWNAM, MON_ONCE, mm_answer_pwnamallow},
177: {MONITOR_REQ_AUTHSERV, MON_ONCE, mm_answer_authserv},
1.10 djm 178: {MONITOR_REQ_AUTH2_READ_BANNER, MON_ONCE, mm_answer_auth2_read_banner},
1.1 provos 179: {MONITOR_REQ_AUTHPASSWORD, MON_AUTH, mm_answer_authpassword},
180: {MONITOR_REQ_BSDAUTHQUERY, MON_ISAUTH, mm_answer_bsdauthquery},
1.66 stevesk 181: {MONITOR_REQ_BSDAUTHRESPOND, MON_AUTH, mm_answer_bsdauthrespond},
1.1 provos 182: {MONITOR_REQ_KEYALLOWED, MON_ISAUTH, mm_answer_keyallowed},
183: {MONITOR_REQ_KEYVERIFY, MON_AUTH, mm_answer_keyverify},
1.46 markus 184: #ifdef GSSAPI
185: {MONITOR_REQ_GSSSETUP, MON_ISAUTH, mm_answer_gss_setup_ctx},
186: {MONITOR_REQ_GSSSTEP, MON_ISAUTH, mm_answer_gss_accept_ctx},
187: {MONITOR_REQ_GSSUSEROK, MON_AUTH, mm_answer_gss_userok},
1.52 markus 188: {MONITOR_REQ_GSSCHECKMIC, MON_ISAUTH, mm_answer_gss_checkmic},
1.46 markus 189: #endif
1.1 provos 190: {0, 0, NULL}
191: };
192:
193: struct mon_table mon_dispatch_postauth20[] = {
194: {MONITOR_REQ_MODULI, 0, mm_answer_moduli},
195: {MONITOR_REQ_SIGN, 0, mm_answer_sign},
196: {MONITOR_REQ_PTY, 0, mm_answer_pty},
197: {MONITOR_REQ_PTYCLEANUP, 0, mm_answer_pty_cleanup},
198: {MONITOR_REQ_TERM, 0, mm_answer_term},
199: {0, 0, NULL}
200: };
201:
202: struct mon_table mon_dispatch_proto15[] = {
203: {MONITOR_REQ_PWNAM, MON_ONCE, mm_answer_pwnamallow},
204: {MONITOR_REQ_SESSKEY, MON_ONCE, mm_answer_sesskey},
205: {MONITOR_REQ_SESSID, MON_ONCE, mm_answer_sessid},
206: {MONITOR_REQ_AUTHPASSWORD, MON_AUTH, mm_answer_authpassword},
1.77 dtucker 207: {MONITOR_REQ_RSAKEYALLOWED, MON_ISAUTH|MON_ALOG, mm_answer_rsa_keyallowed},
208: {MONITOR_REQ_KEYALLOWED, MON_ISAUTH|MON_ALOG, mm_answer_keyallowed},
1.1 provos 209: {MONITOR_REQ_RSACHALLENGE, MON_ONCE, mm_answer_rsa_challenge},
210: {MONITOR_REQ_RSARESPONSE, MON_ONCE|MON_AUTHDECIDE, mm_answer_rsa_response},
211: {MONITOR_REQ_BSDAUTHQUERY, MON_ISAUTH, mm_answer_bsdauthquery},
1.66 stevesk 212: {MONITOR_REQ_BSDAUTHRESPOND, MON_AUTH, mm_answer_bsdauthrespond},
1.1 provos 213: {0, 0, NULL}
214: };
215:
216: struct mon_table mon_dispatch_postauth15[] = {
217: {MONITOR_REQ_PTY, MON_ONCE, mm_answer_pty},
218: {MONITOR_REQ_PTYCLEANUP, MON_ONCE, mm_answer_pty_cleanup},
219: {MONITOR_REQ_TERM, 0, mm_answer_term},
220: {0, 0, NULL}
221: };
222:
223: struct mon_table *mon_dispatch;
224:
225: /* Specifies if a certain message is allowed at the moment */
226:
227: static void
228: monitor_permit(struct mon_table *ent, enum monitor_reqtype type, int permit)
229: {
230: while (ent->f != NULL) {
231: if (ent->type == type) {
232: ent->flags &= ~MON_PERMIT;
233: ent->flags |= permit ? MON_PERMIT : 0;
234: return;
235: }
236: ent++;
237: }
238: }
239:
240: static void
241: monitor_permit_authentications(int permit)
242: {
243: struct mon_table *ent = mon_dispatch;
244:
245: while (ent->f != NULL) {
246: if (ent->flags & MON_AUTH) {
247: ent->flags &= ~MON_PERMIT;
248: ent->flags |= permit ? MON_PERMIT : 0;
249: }
250: ent++;
251: }
252: }
253:
1.50 markus 254: void
255: monitor_child_preauth(Authctxt *_authctxt, struct monitor *pmonitor)
1.1 provos 256: {
257: struct mon_table *ent;
258: int authenticated = 0;
259:
260: debug3("preauth child monitor started");
261:
1.50 markus 262: authctxt = _authctxt;
263: memset(authctxt, 0, sizeof(*authctxt));
264:
1.1 provos 265: if (compat20) {
266: mon_dispatch = mon_dispatch_proto20;
267:
268: /* Permit requests for moduli and signatures */
269: monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
270: monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
271: } else {
272: mon_dispatch = mon_dispatch_proto15;
273:
274: monitor_permit(mon_dispatch, MONITOR_REQ_SESSKEY, 1);
275: }
276:
277: /* The first few requests do not require asynchronous access */
278: while (!authenticated) {
1.77 dtucker 279: auth_method = "unknown";
1.89 markus 280: authenticated = (monitor_read(pmonitor, mon_dispatch, &ent) == 1);
1.1 provos 281: if (authenticated) {
282: if (!(ent->flags & MON_AUTHDECIDE))
283: fatal("%s: unexpected authentication from %d",
1.14 markus 284: __func__, ent->type);
1.1 provos 285: if (authctxt->pw->pw_uid == 0 &&
286: !auth_root_allowed(auth_method))
287: authenticated = 0;
288: }
289:
1.77 dtucker 290: if (ent->flags & (MON_AUTHDECIDE|MON_ALOG)) {
1.1 provos 291: auth_log(authctxt, authenticated, auth_method,
292: compat20 ? " ssh2" : "");
293: if (!authenticated)
294: authctxt->failures++;
295: }
296: }
297:
298: if (!authctxt->valid)
1.14 markus 299: fatal("%s: authenticated invalid user", __func__);
1.77 dtucker 300: if (strcmp(auth_method, "unknown") == 0)
301: fatal("%s: authentication method name unknown", __func__);
1.1 provos 302:
303: debug("%s: %s has been authenticated by privileged process",
1.14 markus 304: __func__, authctxt->user);
1.1 provos 305:
1.11 mouring 306: mm_get_keystate(pmonitor);
1.1 provos 307: }
308:
1.40 markus 309: static void
310: monitor_set_child_handler(pid_t pid)
311: {
312: monitor_child_pid = pid;
313: }
314:
315: static void
1.59 avsm 316: monitor_child_handler(int sig)
1.40 markus 317: {
1.59 avsm 318: kill(monitor_child_pid, sig);
1.40 markus 319: }
320:
1.1 provos 321: void
1.11 mouring 322: monitor_child_postauth(struct monitor *pmonitor)
1.1 provos 323: {
1.40 markus 324: monitor_set_child_handler(pmonitor->m_pid);
325: signal(SIGHUP, &monitor_child_handler);
326: signal(SIGTERM, &monitor_child_handler);
1.91 djm 327: signal(SIGINT, &monitor_child_handler);
1.40 markus 328:
1.1 provos 329: if (compat20) {
330: mon_dispatch = mon_dispatch_postauth20;
331:
332: /* Permit requests for moduli and signatures */
333: monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
334: monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
335: monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1);
336: } else {
337: mon_dispatch = mon_dispatch_postauth15;
338: monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1);
339: }
340: if (!no_pty_flag) {
341: monitor_permit(mon_dispatch, MONITOR_REQ_PTY, 1);
342: monitor_permit(mon_dispatch, MONITOR_REQ_PTYCLEANUP, 1);
343: }
344:
345: for (;;)
1.11 mouring 346: monitor_read(pmonitor, mon_dispatch, NULL);
1.1 provos 347: }
348:
349: void
1.11 mouring 350: monitor_sync(struct monitor *pmonitor)
1.1 provos 351: {
1.16 djm 352: if (options.compression) {
353: /* The member allocation is not visible, so sync it */
354: mm_share_sync(&pmonitor->m_zlib, &pmonitor->m_zback);
355: }
1.1 provos 356: }
357:
358: int
1.11 mouring 359: monitor_read(struct monitor *pmonitor, struct mon_table *ent,
1.1 provos 360: struct mon_table **pent)
361: {
362: Buffer m;
363: int ret;
364: u_char type;
365:
366: buffer_init(&m);
367:
1.11 mouring 368: mm_request_receive(pmonitor->m_sendfd, &m);
1.1 provos 369: type = buffer_get_char(&m);
370:
1.14 markus 371: debug3("%s: checking request %d", __func__, type);
1.1 provos 372:
373: while (ent->f != NULL) {
374: if (ent->type == type)
375: break;
376: ent++;
377: }
378:
379: if (ent->f != NULL) {
380: if (!(ent->flags & MON_PERMIT))
1.14 markus 381: fatal("%s: unpermitted request %d", __func__,
1.1 provos 382: type);
1.11 mouring 383: ret = (*ent->f)(pmonitor->m_sendfd, &m);
1.1 provos 384: buffer_free(&m);
385:
386: /* The child may use this request only once, disable it */
387: if (ent->flags & MON_ONCE) {
1.14 markus 388: debug2("%s: %d used once, disabling now", __func__,
1.1 provos 389: type);
390: ent->flags &= ~MON_PERMIT;
391: }
392:
393: if (pent != NULL)
394: *pent = ent;
1.3 markus 395:
1.1 provos 396: return ret;
397: }
398:
1.14 markus 399: fatal("%s: unsupported request: %d", __func__, type);
1.1 provos 400:
401: /* NOTREACHED */
402: return (-1);
403: }
404:
405: /* allowed key state */
406: static int
407: monitor_allowed_key(u_char *blob, u_int bloblen)
408: {
409: /* make sure key is allowed */
410: if (key_blob == NULL || key_bloblen != bloblen ||
411: memcmp(key_blob, blob, key_bloblen))
412: return (0);
413: return (1);
414: }
415:
416: static void
417: monitor_reset_key_state(void)
418: {
419: /* reset state */
420: if (key_blob != NULL)
421: xfree(key_blob);
422: if (hostbased_cuser != NULL)
423: xfree(hostbased_cuser);
424: if (hostbased_chost != NULL)
425: xfree(hostbased_chost);
426: key_blob = NULL;
427: key_bloblen = 0;
428: key_blobtype = MM_NOKEY;
429: hostbased_cuser = NULL;
430: hostbased_chost = NULL;
431: }
432:
433: int
1.59 avsm 434: mm_answer_moduli(int sock, Buffer *m)
1.1 provos 435: {
436: DH *dh;
437: int min, want, max;
438:
439: min = buffer_get_int(m);
440: want = buffer_get_int(m);
441: max = buffer_get_int(m);
442:
443: debug3("%s: got parameters: %d %d %d",
1.14 markus 444: __func__, min, want, max);
1.1 provos 445: /* We need to check here, too, in case the child got corrupted */
446: if (max < min || want < min || max < want)
447: fatal("%s: bad parameters: %d %d %d",
1.14 markus 448: __func__, min, want, max);
1.1 provos 449:
450: buffer_clear(m);
451:
452: dh = choose_dh(min, want, max);
453: if (dh == NULL) {
454: buffer_put_char(m, 0);
455: return (0);
456: } else {
457: /* Send first bignum */
458: buffer_put_char(m, 1);
459: buffer_put_bignum2(m, dh->p);
460: buffer_put_bignum2(m, dh->g);
1.3 markus 461:
1.1 provos 462: DH_free(dh);
463: }
1.59 avsm 464: mm_request_send(sock, MONITOR_ANS_MODULI, m);
1.1 provos 465: return (0);
466: }
467:
468: int
1.59 avsm 469: mm_answer_sign(int sock, Buffer *m)
1.1 provos 470: {
471: Key *key;
472: u_char *p;
473: u_char *signature;
474: u_int siglen, datlen;
475: int keyid;
1.3 markus 476:
1.14 markus 477: debug3("%s", __func__);
1.1 provos 478:
1.3 markus 479: keyid = buffer_get_int(m);
480: p = buffer_get_string(m, &datlen);
1.1 provos 481:
1.69 djm 482: /*
1.71 deraadt 483: * Supported KEX types will only return SHA1 (20 byte) or
1.69 djm 484: * SHA256 (32 byte) hashes
485: */
486: if (datlen != 20 && datlen != 32)
1.19 deraadt 487: fatal("%s: data length incorrect: %u", __func__, datlen);
1.1 provos 488:
1.13 markus 489: /* save session id, it will be passed on the first call */
490: if (session_id2_len == 0) {
491: session_id2_len = datlen;
492: session_id2 = xmalloc(session_id2_len);
493: memcpy(session_id2, p, session_id2_len);
494: }
495:
1.1 provos 496: if ((key = get_hostkey_by_index(keyid)) == NULL)
1.14 markus 497: fatal("%s: no hostkey from index %d", __func__, keyid);
1.1 provos 498: if (key_sign(key, &signature, &siglen, p, datlen) < 0)
1.14 markus 499: fatal("%s: key_sign failed", __func__);
1.1 provos 500:
1.19 deraadt 501: debug3("%s: signature %p(%u)", __func__, signature, siglen);
1.1 provos 502:
503: buffer_clear(m);
504: buffer_put_string(m, signature, siglen);
505:
506: xfree(p);
507: xfree(signature);
508:
1.59 avsm 509: mm_request_send(sock, MONITOR_ANS_SIGN, m);
1.1 provos 510:
511: /* Turn on permissions for getpwnam */
512: monitor_permit(mon_dispatch, MONITOR_REQ_PWNAM, 1);
513:
514: return (0);
515: }
516:
517: /* Retrieves the password entry and also checks if the user is permitted */
518:
519: int
1.59 avsm 520: mm_answer_pwnamallow(int sock, Buffer *m)
1.1 provos 521: {
1.60 dtucker 522: char *username;
1.1 provos 523: struct passwd *pwent;
524: int allowed = 0;
1.3 markus 525:
1.14 markus 526: debug3("%s", __func__);
1.1 provos 527:
528: if (authctxt->attempt++ != 0)
1.14 markus 529: fatal("%s: multiple attempts for getpwnam", __func__);
1.1 provos 530:
1.60 dtucker 531: username = buffer_get_string(m, NULL);
1.1 provos 532:
1.60 dtucker 533: pwent = getpwnamallow(username);
1.1 provos 534:
1.60 dtucker 535: authctxt->user = xstrdup(username);
536: setproctitle("%s [priv]", pwent ? username : "unknown");
537: xfree(username);
1.1 provos 538:
539: buffer_clear(m);
540:
541: if (pwent == NULL) {
542: buffer_put_char(m, 0);
1.53 djm 543: authctxt->pw = fakepw();
1.1 provos 544: goto out;
545: }
546:
547: allowed = 1;
1.4 markus 548: authctxt->pw = pwent;
1.1 provos 549: authctxt->valid = 1;
550:
551: buffer_put_char(m, 1);
552: buffer_put_string(m, pwent, sizeof(struct passwd));
553: buffer_put_cstring(m, pwent->pw_name);
554: buffer_put_cstring(m, "*");
555: buffer_put_cstring(m, pwent->pw_gecos);
556: buffer_put_cstring(m, pwent->pw_class);
557: buffer_put_cstring(m, pwent->pw_dir);
558: buffer_put_cstring(m, pwent->pw_shell);
1.94 ! dtucker 559:
! 560: out:
1.90 dtucker 561: buffer_put_string(m, &options, sizeof(options));
562: if (options.banner != NULL)
563: buffer_put_cstring(m, options.banner);
1.14 markus 564: debug3("%s: sending MONITOR_ANS_PWNAM: %d", __func__, allowed);
1.59 avsm 565: mm_request_send(sock, MONITOR_ANS_PWNAM, m);
1.1 provos 566:
567: /* For SSHv1 allow authentication now */
568: if (!compat20)
569: monitor_permit_authentications(1);
1.10 djm 570: else {
1.1 provos 571: /* Allow service/style information on the auth context */
572: monitor_permit(mon_dispatch, MONITOR_REQ_AUTHSERV, 1);
1.10 djm 573: monitor_permit(mon_dispatch, MONITOR_REQ_AUTH2_READ_BANNER, 1);
574: }
575:
576:
577: return (0);
578: }
579:
1.59 avsm 580: int mm_answer_auth2_read_banner(int sock, Buffer *m)
1.10 djm 581: {
582: char *banner;
583:
584: buffer_clear(m);
585: banner = auth2_read_banner();
586: buffer_put_cstring(m, banner != NULL ? banner : "");
1.59 avsm 587: mm_request_send(sock, MONITOR_ANS_AUTH2_READ_BANNER, m);
1.1 provos 588:
1.10 djm 589: if (banner != NULL)
1.21 deraadt 590: xfree(banner);
1.1 provos 591:
592: return (0);
593: }
594:
595: int
1.59 avsm 596: mm_answer_authserv(int sock, Buffer *m)
1.1 provos 597: {
598: monitor_permit_authentications(1);
599:
600: authctxt->service = buffer_get_string(m, NULL);
601: authctxt->style = buffer_get_string(m, NULL);
1.6 stevesk 602: debug3("%s: service=%s, style=%s",
1.14 markus 603: __func__, authctxt->service, authctxt->style);
1.6 stevesk 604:
1.1 provos 605: if (strlen(authctxt->style) == 0) {
606: xfree(authctxt->style);
607: authctxt->style = NULL;
608: }
609:
610: return (0);
611: }
612:
613: int
1.59 avsm 614: mm_answer_authpassword(int sock, Buffer *m)
1.1 provos 615: {
616: static int call_count;
617: char *passwd;
1.22 stevesk 618: int authenticated;
619: u_int plen;
1.1 provos 620:
621: passwd = buffer_get_string(m, &plen);
622: /* Only authenticate if the context is valid */
1.12 markus 623: authenticated = options.password_authentication &&
1.48 markus 624: auth_password(authctxt, passwd);
1.1 provos 625: memset(passwd, 0, strlen(passwd));
626: xfree(passwd);
627:
628: buffer_clear(m);
629: buffer_put_int(m, authenticated);
630:
1.14 markus 631: debug3("%s: sending result %d", __func__, authenticated);
1.59 avsm 632: mm_request_send(sock, MONITOR_ANS_AUTHPASSWORD, m);
1.1 provos 633:
634: call_count++;
635: if (plen == 0 && call_count == 1)
636: auth_method = "none";
637: else
638: auth_method = "password";
639:
640: /* Causes monitor loop to terminate if authenticated */
641: return (authenticated);
642: }
643:
644: int
1.59 avsm 645: mm_answer_bsdauthquery(int sock, Buffer *m)
1.1 provos 646: {
647: char *name, *infotxt;
648: u_int numprompts;
649: u_int *echo_on;
650: char **prompts;
1.31 markus 651: u_int success;
1.1 provos 652:
1.31 markus 653: success = bsdauth_query(authctxt, &name, &infotxt, &numprompts,
654: &prompts, &echo_on) < 0 ? 0 : 1;
1.1 provos 655:
656: buffer_clear(m);
1.31 markus 657: buffer_put_int(m, success);
658: if (success)
1.1 provos 659: buffer_put_cstring(m, prompts[0]);
660:
1.31 markus 661: debug3("%s: sending challenge success: %u", __func__, success);
1.59 avsm 662: mm_request_send(sock, MONITOR_ANS_BSDAUTHQUERY, m);
1.1 provos 663:
1.31 markus 664: if (success) {
1.1 provos 665: xfree(name);
666: xfree(infotxt);
667: xfree(prompts);
668: xfree(echo_on);
669: }
670:
671: return (0);
672: }
673:
674: int
1.59 avsm 675: mm_answer_bsdauthrespond(int sock, Buffer *m)
1.1 provos 676: {
677: char *response;
678: int authok;
679:
680: if (authctxt->as == 0)
1.14 markus 681: fatal("%s: no bsd auth session", __func__);
1.1 provos 682:
683: response = buffer_get_string(m, NULL);
1.12 markus 684: authok = options.challenge_response_authentication &&
685: auth_userresponse(authctxt->as, response, 0);
1.1 provos 686: authctxt->as = NULL;
1.14 markus 687: debug3("%s: <%s> = <%d>", __func__, response, authok);
1.1 provos 688: xfree(response);
689:
690: buffer_clear(m);
691: buffer_put_int(m, authok);
692:
1.14 markus 693: debug3("%s: sending authenticated: %d", __func__, authok);
1.59 avsm 694: mm_request_send(sock, MONITOR_ANS_BSDAUTHRESPOND, m);
1.1 provos 695:
696: auth_method = "bsdauth";
697:
698: return (authok != 0);
699: }
700:
701:
1.2 markus 702: static void
1.1 provos 703: mm_append_debug(Buffer *m)
704: {
705: if (auth_debug_init && buffer_len(&auth_debug)) {
1.14 markus 706: debug3("%s: Appending debug messages for child", __func__);
1.1 provos 707: buffer_append(m, buffer_ptr(&auth_debug),
708: buffer_len(&auth_debug));
709: buffer_clear(&auth_debug);
710: }
711: }
712:
713: int
1.59 avsm 714: mm_answer_keyallowed(int sock, Buffer *m)
1.1 provos 715: {
716: Key *key;
1.26 markus 717: char *cuser, *chost;
718: u_char *blob;
1.1 provos 719: u_int bloblen;
720: enum mm_keytype type = 0;
721: int allowed = 0;
722:
1.14 markus 723: debug3("%s entering", __func__);
1.3 markus 724:
1.1 provos 725: type = buffer_get_int(m);
726: cuser = buffer_get_string(m, NULL);
727: chost = buffer_get_string(m, NULL);
728: blob = buffer_get_string(m, &bloblen);
729:
730: key = key_from_blob(blob, bloblen);
731:
732: if ((compat20 && type == MM_RSAHOSTKEY) ||
733: (!compat20 && type != MM_RSAHOSTKEY))
1.14 markus 734: fatal("%s: key type and protocol mismatch", __func__);
1.1 provos 735:
1.14 markus 736: debug3("%s: key_from_blob: %p", __func__, key);
1.1 provos 737:
1.51 djm 738: if (key != NULL && authctxt->valid) {
1.63 deraadt 739: switch (type) {
1.1 provos 740: case MM_USERKEY:
1.12 markus 741: allowed = options.pubkey_authentication &&
742: user_key_allowed(authctxt->pw, key);
1.77 dtucker 743: auth_method = "publickey";
1.1 provos 744: break;
745: case MM_HOSTKEY:
1.12 markus 746: allowed = options.hostbased_authentication &&
747: hostbased_key_allowed(authctxt->pw,
1.1 provos 748: cuser, chost, key);
1.77 dtucker 749: auth_method = "hostbased";
1.1 provos 750: break;
751: case MM_RSAHOSTKEY:
752: key->type = KEY_RSA1; /* XXX */
1.12 markus 753: allowed = options.rhosts_rsa_authentication &&
754: auth_rhosts_rsa_key_allowed(authctxt->pw,
1.1 provos 755: cuser, chost, key);
1.77 dtucker 756: auth_method = "rsa";
1.1 provos 757: break;
758: default:
1.14 markus 759: fatal("%s: unknown key type %d", __func__, type);
1.1 provos 760: break;
761: }
1.33 markus 762: }
763: if (key != NULL)
1.1 provos 764: key_free(key);
765:
766: /* clear temporarily storage (used by verify) */
767: monitor_reset_key_state();
768:
769: if (allowed) {
770: /* Save temporarily for comparison in verify */
771: key_blob = blob;
772: key_bloblen = bloblen;
773: key_blobtype = type;
774: hostbased_cuser = cuser;
775: hostbased_chost = chost;
1.72 djm 776: } else {
1.77 dtucker 777: /* Log failed attempt */
778: auth_log(authctxt, 0, auth_method, compat20 ? " ssh2" : "");
1.72 djm 779: xfree(blob);
780: xfree(cuser);
781: xfree(chost);
1.1 provos 782: }
783:
784: debug3("%s: key %p is %s",
1.14 markus 785: __func__, key, allowed ? "allowed" : "disallowed");
1.1 provos 786:
787: buffer_clear(m);
788: buffer_put_int(m, allowed);
1.32 markus 789: buffer_put_int(m, forced_command != NULL);
1.1 provos 790:
791: mm_append_debug(m);
792:
1.59 avsm 793: mm_request_send(sock, MONITOR_ANS_KEYALLOWED, m);
1.1 provos 794:
795: if (type == MM_RSAHOSTKEY)
796: monitor_permit(mon_dispatch, MONITOR_REQ_RSACHALLENGE, allowed);
797:
798: return (0);
799: }
800:
801: static int
802: monitor_valid_userblob(u_char *data, u_int datalen)
803: {
804: Buffer b;
1.26 markus 805: char *p;
1.1 provos 806: u_int len;
807: int fail = 0;
808:
809: buffer_init(&b);
810: buffer_append(&b, data, datalen);
1.3 markus 811:
1.1 provos 812: if (datafellows & SSH_OLD_SESSIONID) {
1.13 markus 813: p = buffer_ptr(&b);
814: len = buffer_len(&b);
815: if ((session_id2 == NULL) ||
816: (len < session_id2_len) ||
817: (memcmp(p, session_id2, session_id2_len) != 0))
818: fail++;
1.1 provos 819: buffer_consume(&b, session_id2_len);
820: } else {
1.13 markus 821: p = buffer_get_string(&b, &len);
822: if ((session_id2 == NULL) ||
823: (len != session_id2_len) ||
824: (memcmp(p, session_id2, session_id2_len) != 0))
1.1 provos 825: fail++;
1.13 markus 826: xfree(p);
1.1 provos 827: }
828: if (buffer_get_char(&b) != SSH2_MSG_USERAUTH_REQUEST)
829: fail++;
830: p = buffer_get_string(&b, NULL);
831: if (strcmp(authctxt->user, p) != 0) {
1.38 itojun 832: logit("wrong user name passed to monitor: expected %s != %.100s",
1.1 provos 833: authctxt->user, p);
834: fail++;
835: }
836: xfree(p);
837: buffer_skip_string(&b);
838: if (datafellows & SSH_BUG_PKAUTH) {
839: if (!buffer_get_char(&b))
840: fail++;
841: } else {
842: p = buffer_get_string(&b, NULL);
843: if (strcmp("publickey", p) != 0)
844: fail++;
845: xfree(p);
846: if (!buffer_get_char(&b))
847: fail++;
848: buffer_skip_string(&b);
849: }
850: buffer_skip_string(&b);
851: if (buffer_len(&b) != 0)
852: fail++;
853: buffer_free(&b);
854: return (fail == 0);
855: }
856:
857: static int
1.26 markus 858: monitor_valid_hostbasedblob(u_char *data, u_int datalen, char *cuser,
859: char *chost)
1.1 provos 860: {
861: Buffer b;
1.26 markus 862: char *p;
1.1 provos 863: u_int len;
864: int fail = 0;
865:
866: buffer_init(&b);
867: buffer_append(&b, data, datalen);
1.3 markus 868:
1.13 markus 869: p = buffer_get_string(&b, &len);
870: if ((session_id2 == NULL) ||
871: (len != session_id2_len) ||
872: (memcmp(p, session_id2, session_id2_len) != 0))
1.1 provos 873: fail++;
1.13 markus 874: xfree(p);
875:
1.1 provos 876: if (buffer_get_char(&b) != SSH2_MSG_USERAUTH_REQUEST)
877: fail++;
878: p = buffer_get_string(&b, NULL);
879: if (strcmp(authctxt->user, p) != 0) {
1.38 itojun 880: logit("wrong user name passed to monitor: expected %s != %.100s",
1.1 provos 881: authctxt->user, p);
882: fail++;
883: }
884: xfree(p);
885: buffer_skip_string(&b); /* service */
886: p = buffer_get_string(&b, NULL);
887: if (strcmp(p, "hostbased") != 0)
888: fail++;
889: xfree(p);
890: buffer_skip_string(&b); /* pkalg */
891: buffer_skip_string(&b); /* pkblob */
892:
893: /* verify client host, strip trailing dot if necessary */
894: p = buffer_get_string(&b, NULL);
895: if (((len = strlen(p)) > 0) && p[len - 1] == '.')
896: p[len - 1] = '\0';
897: if (strcmp(p, chost) != 0)
898: fail++;
899: xfree(p);
900:
901: /* verify client user */
902: p = buffer_get_string(&b, NULL);
903: if (strcmp(p, cuser) != 0)
904: fail++;
905: xfree(p);
906:
907: if (buffer_len(&b) != 0)
908: fail++;
909: buffer_free(&b);
910: return (fail == 0);
911: }
912:
913: int
1.59 avsm 914: mm_answer_keyverify(int sock, Buffer *m)
1.1 provos 915: {
916: Key *key;
917: u_char *signature, *data, *blob;
918: u_int signaturelen, datalen, bloblen;
919: int verified = 0;
920: int valid_data = 0;
921:
922: blob = buffer_get_string(m, &bloblen);
923: signature = buffer_get_string(m, &signaturelen);
924: data = buffer_get_string(m, &datalen);
925:
926: if (hostbased_cuser == NULL || hostbased_chost == NULL ||
1.8 mouring 927: !monitor_allowed_key(blob, bloblen))
1.14 markus 928: fatal("%s: bad key, not previously allowed", __func__);
1.1 provos 929:
930: key = key_from_blob(blob, bloblen);
931: if (key == NULL)
1.14 markus 932: fatal("%s: bad public key blob", __func__);
1.1 provos 933:
934: switch (key_blobtype) {
935: case MM_USERKEY:
936: valid_data = monitor_valid_userblob(data, datalen);
937: break;
938: case MM_HOSTKEY:
939: valid_data = monitor_valid_hostbasedblob(data, datalen,
940: hostbased_cuser, hostbased_chost);
941: break;
942: default:
943: valid_data = 0;
944: break;
945: }
946: if (!valid_data)
1.14 markus 947: fatal("%s: bad signature data blob", __func__);
1.1 provos 948:
949: verified = key_verify(key, signature, signaturelen, data, datalen);
950: debug3("%s: key %p signature %s",
1.89 markus 951: __func__, key, (verified == 1) ? "verified" : "unverified");
1.1 provos 952:
953: key_free(key);
954: xfree(blob);
955: xfree(signature);
956: xfree(data);
957:
1.17 stevesk 958: auth_method = key_blobtype == MM_USERKEY ? "publickey" : "hostbased";
959:
1.1 provos 960: monitor_reset_key_state();
1.3 markus 961:
1.1 provos 962: buffer_clear(m);
963: buffer_put_int(m, verified);
1.59 avsm 964: mm_request_send(sock, MONITOR_ANS_KEYVERIFY, m);
1.1 provos 965:
1.89 markus 966: return (verified == 1);
1.1 provos 967: }
968:
1.2 markus 969: static void
1.1 provos 970: mm_record_login(Session *s, struct passwd *pw)
971: {
972: socklen_t fromlen;
973: struct sockaddr_storage from;
974:
975: /*
976: * Get IP address of client. If the connection is not a socket, let
977: * the address be 0.0.0.0.
978: */
979: memset(&from, 0, sizeof(from));
1.24 stevesk 980: fromlen = sizeof(from);
1.1 provos 981: if (packet_connection_is_on_socket()) {
982: if (getpeername(packet_get_connection_in(),
1.74 deraadt 983: (struct sockaddr *)&from, &fromlen) < 0) {
1.1 provos 984: debug("getpeername: %.100s", strerror(errno));
1.50 markus 985: cleanup_exit(255);
1.1 provos 986: }
987: }
988: /* Record that there was a login on that tty from the remote host. */
989: record_login(s->pid, s->tty, pw->pw_name, pw->pw_uid,
1.42 markus 990: get_remote_name_or_ip(utmp_len, options.use_dns),
1.24 stevesk 991: (struct sockaddr *)&from, fromlen);
1.1 provos 992: }
993:
994: static void
995: mm_session_close(Session *s)
996: {
1.41 djm 997: debug3("%s: session %d pid %ld", __func__, s->self, (long)s->pid);
1.1 provos 998: if (s->ttyfd != -1) {
1.86 stevesk 999: debug3("%s: tty %s ptyfd %d", __func__, s->tty, s->ptyfd);
1.1 provos 1000: session_pty_cleanup2(s);
1001: }
1002: s->used = 0;
1003: }
1004:
1005: int
1.59 avsm 1006: mm_answer_pty(int sock, Buffer *m)
1.1 provos 1007: {
1.11 mouring 1008: extern struct monitor *pmonitor;
1.1 provos 1009: Session *s;
1010: int res, fd0;
1011:
1.14 markus 1012: debug3("%s entering", __func__);
1.1 provos 1013:
1014: buffer_clear(m);
1015: s = session_new();
1016: if (s == NULL)
1017: goto error;
1018: s->authctxt = authctxt;
1019: s->pw = authctxt->pw;
1.11 mouring 1020: s->pid = pmonitor->m_pid;
1.1 provos 1021: res = pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty));
1022: if (res == 0)
1023: goto error;
1024: pty_setowner(authctxt->pw, s->tty);
1025:
1026: buffer_put_int(m, 1);
1027: buffer_put_cstring(m, s->tty);
1028:
1029: /* We need to trick ttyslot */
1030: if (dup2(s->ttyfd, 0) == -1)
1.14 markus 1031: fatal("%s: dup2", __func__);
1.1 provos 1032:
1033: mm_record_login(s, authctxt->pw);
1034:
1035: /* Now we can close the file descriptor again */
1036: close(0);
1.61 dtucker 1037:
1038: /* send messages generated by record_login */
1039: buffer_put_string(m, buffer_ptr(&loginmsg), buffer_len(&loginmsg));
1040: buffer_clear(&loginmsg);
1041:
1042: mm_request_send(sock, MONITOR_ANS_PTY, m);
1043:
1.92 djm 1044: if (mm_send_fd(sock, s->ptyfd) == -1 ||
1045: mm_send_fd(sock, s->ttyfd) == -1)
1046: fatal("%s: send fds failed", __func__);
1.1 provos 1047:
1048: /* make sure nothing uses fd 0 */
1049: if ((fd0 = open(_PATH_DEVNULL, O_RDONLY)) < 0)
1.14 markus 1050: fatal("%s: open(/dev/null): %s", __func__, strerror(errno));
1.1 provos 1051: if (fd0 != 0)
1.14 markus 1052: error("%s: fd0 %d != 0", __func__, fd0);
1.1 provos 1053:
1054: /* slave is not needed */
1055: close(s->ttyfd);
1056: s->ttyfd = s->ptyfd;
1057: /* no need to dup() because nobody closes ptyfd */
1058: s->ptymaster = s->ptyfd;
1059:
1.86 stevesk 1060: debug3("%s: tty %s ptyfd %d", __func__, s->tty, s->ttyfd);
1.1 provos 1061:
1062: return (0);
1063:
1064: error:
1065: if (s != NULL)
1066: mm_session_close(s);
1067: buffer_put_int(m, 0);
1.59 avsm 1068: mm_request_send(sock, MONITOR_ANS_PTY, m);
1.1 provos 1069: return (0);
1070: }
1071:
1072: int
1.59 avsm 1073: mm_answer_pty_cleanup(int sock, Buffer *m)
1.1 provos 1074: {
1075: Session *s;
1076: char *tty;
1077:
1.14 markus 1078: debug3("%s entering", __func__);
1.1 provos 1079:
1080: tty = buffer_get_string(m, NULL);
1081: if ((s = session_by_tty(tty)) != NULL)
1082: mm_session_close(s);
1083: buffer_clear(m);
1084: xfree(tty);
1085: return (0);
1086: }
1087:
1088: int
1.59 avsm 1089: mm_answer_sesskey(int sock, Buffer *m)
1.1 provos 1090: {
1091: BIGNUM *p;
1092: int rsafail;
1093:
1094: /* Turn off permissions */
1.62 dtucker 1095: monitor_permit(mon_dispatch, MONITOR_REQ_SESSKEY, 0);
1.1 provos 1096:
1097: if ((p = BN_new()) == NULL)
1.14 markus 1098: fatal("%s: BN_new", __func__);
1.1 provos 1099:
1100: buffer_get_bignum2(m, p);
1101:
1102: rsafail = ssh1_session_key(p);
1103:
1104: buffer_clear(m);
1105: buffer_put_int(m, rsafail);
1106: buffer_put_bignum2(m, p);
1107:
1108: BN_clear_free(p);
1109:
1.59 avsm 1110: mm_request_send(sock, MONITOR_ANS_SESSKEY, m);
1.1 provos 1111:
1112: /* Turn on permissions for sessid passing */
1113: monitor_permit(mon_dispatch, MONITOR_REQ_SESSID, 1);
1114:
1115: return (0);
1116: }
1117:
1118: int
1.59 avsm 1119: mm_answer_sessid(int sock, Buffer *m)
1.1 provos 1120: {
1121: int i;
1122:
1.14 markus 1123: debug3("%s entering", __func__);
1.1 provos 1124:
1125: if (buffer_len(m) != 16)
1.14 markus 1126: fatal("%s: bad ssh1 session id", __func__);
1.1 provos 1127: for (i = 0; i < 16; i++)
1128: session_id[i] = buffer_get_char(m);
1129:
1130: /* Turn on permissions for getpwnam */
1131: monitor_permit(mon_dispatch, MONITOR_REQ_PWNAM, 1);
1132:
1133: return (0);
1134: }
1135:
1136: int
1.59 avsm 1137: mm_answer_rsa_keyallowed(int sock, Buffer *m)
1.1 provos 1138: {
1139: BIGNUM *client_n;
1140: Key *key = NULL;
1.3 markus 1141: u_char *blob = NULL;
1142: u_int blen = 0;
1.1 provos 1143: int allowed = 0;
1144:
1.14 markus 1145: debug3("%s entering", __func__);
1.1 provos 1146:
1.77 dtucker 1147: auth_method = "rsa";
1.12 markus 1148: if (options.rsa_authentication && authctxt->valid) {
1.1 provos 1149: if ((client_n = BN_new()) == NULL)
1.14 markus 1150: fatal("%s: BN_new", __func__);
1.1 provos 1151: buffer_get_bignum2(m, client_n);
1152: allowed = auth_rsa_key_allowed(authctxt->pw, client_n, &key);
1153: BN_clear_free(client_n);
1154: }
1155: buffer_clear(m);
1156: buffer_put_int(m, allowed);
1.32 markus 1157: buffer_put_int(m, forced_command != NULL);
1.1 provos 1158:
1159: /* clear temporarily storage (used by generate challenge) */
1160: monitor_reset_key_state();
1161:
1162: if (allowed && key != NULL) {
1163: key->type = KEY_RSA; /* cheat for key_to_blob */
1164: if (key_to_blob(key, &blob, &blen) == 0)
1.14 markus 1165: fatal("%s: key_to_blob failed", __func__);
1.1 provos 1166: buffer_put_string(m, blob, blen);
1167:
1168: /* Save temporarily for comparison in verify */
1169: key_blob = blob;
1170: key_bloblen = blen;
1171: key_blobtype = MM_RSAUSERKEY;
1.33 markus 1172: }
1173: if (key != NULL)
1.1 provos 1174: key_free(key);
1175:
1176: mm_append_debug(m);
1177:
1.59 avsm 1178: mm_request_send(sock, MONITOR_ANS_RSAKEYALLOWED, m);
1.1 provos 1179:
1180: monitor_permit(mon_dispatch, MONITOR_REQ_RSACHALLENGE, allowed);
1181: monitor_permit(mon_dispatch, MONITOR_REQ_RSARESPONSE, 0);
1182: return (0);
1183: }
1184:
1185: int
1.59 avsm 1186: mm_answer_rsa_challenge(int sock, Buffer *m)
1.1 provos 1187: {
1188: Key *key = NULL;
1.3 markus 1189: u_char *blob;
1190: u_int blen;
1.1 provos 1191:
1.14 markus 1192: debug3("%s entering", __func__);
1.1 provos 1193:
1194: if (!authctxt->valid)
1.14 markus 1195: fatal("%s: authctxt not valid", __func__);
1.1 provos 1196: blob = buffer_get_string(m, &blen);
1197: if (!monitor_allowed_key(blob, blen))
1.14 markus 1198: fatal("%s: bad key, not previously allowed", __func__);
1.1 provos 1199: if (key_blobtype != MM_RSAUSERKEY && key_blobtype != MM_RSAHOSTKEY)
1.14 markus 1200: fatal("%s: key type mismatch", __func__);
1.1 provos 1201: if ((key = key_from_blob(blob, blen)) == NULL)
1.14 markus 1202: fatal("%s: received bad key", __func__);
1.1 provos 1203:
1204: if (ssh1_challenge)
1205: BN_clear_free(ssh1_challenge);
1206: ssh1_challenge = auth_rsa_generate_challenge(key);
1207:
1208: buffer_clear(m);
1209: buffer_put_bignum2(m, ssh1_challenge);
1210:
1.14 markus 1211: debug3("%s sending reply", __func__);
1.59 avsm 1212: mm_request_send(sock, MONITOR_ANS_RSACHALLENGE, m);
1.1 provos 1213:
1214: monitor_permit(mon_dispatch, MONITOR_REQ_RSARESPONSE, 1);
1.33 markus 1215:
1216: xfree(blob);
1217: key_free(key);
1.1 provos 1218: return (0);
1219: }
1220:
1221: int
1.59 avsm 1222: mm_answer_rsa_response(int sock, Buffer *m)
1.1 provos 1223: {
1224: Key *key = NULL;
1.3 markus 1225: u_char *blob, *response;
1226: u_int blen, len;
1227: int success;
1.1 provos 1228:
1.14 markus 1229: debug3("%s entering", __func__);
1.1 provos 1230:
1231: if (!authctxt->valid)
1.14 markus 1232: fatal("%s: authctxt not valid", __func__);
1.1 provos 1233: if (ssh1_challenge == NULL)
1.14 markus 1234: fatal("%s: no ssh1_challenge", __func__);
1.1 provos 1235:
1236: blob = buffer_get_string(m, &blen);
1237: if (!monitor_allowed_key(blob, blen))
1.14 markus 1238: fatal("%s: bad key, not previously allowed", __func__);
1.1 provos 1239: if (key_blobtype != MM_RSAUSERKEY && key_blobtype != MM_RSAHOSTKEY)
1.14 markus 1240: fatal("%s: key type mismatch: %d", __func__, key_blobtype);
1.1 provos 1241: if ((key = key_from_blob(blob, blen)) == NULL)
1.14 markus 1242: fatal("%s: received bad key", __func__);
1.1 provos 1243: response = buffer_get_string(m, &len);
1244: if (len != 16)
1.14 markus 1245: fatal("%s: received bad response to challenge", __func__);
1.1 provos 1246: success = auth_rsa_verify_response(key, ssh1_challenge, response);
1247:
1.33 markus 1248: xfree(blob);
1.1 provos 1249: key_free(key);
1250: xfree(response);
1251:
1252: auth_method = key_blobtype == MM_RSAUSERKEY ? "rsa" : "rhosts-rsa";
1253:
1254: /* reset state */
1255: BN_clear_free(ssh1_challenge);
1256: ssh1_challenge = NULL;
1257: monitor_reset_key_state();
1258:
1259: buffer_clear(m);
1260: buffer_put_int(m, success);
1.59 avsm 1261: mm_request_send(sock, MONITOR_ANS_RSARESPONSE, m);
1.1 provos 1262:
1263: return (success);
1264: }
1265:
1266: int
1.59 avsm 1267: mm_answer_term(int sock, Buffer *req)
1.1 provos 1268: {
1.11 mouring 1269: extern struct monitor *pmonitor;
1.1 provos 1270: int res, status;
1271:
1.14 markus 1272: debug3("%s: tearing down sessions", __func__);
1.1 provos 1273:
1274: /* The child is terminating */
1275: session_destroy_all(&mm_session_close);
1276:
1.11 mouring 1277: while (waitpid(pmonitor->m_pid, &status, 0) == -1)
1.9 markus 1278: if (errno != EINTR)
1279: exit(1);
1.1 provos 1280:
1281: res = WIFEXITED(status) ? WEXITSTATUS(status) : 1;
1282:
1283: /* Terminate process */
1.57 deraadt 1284: exit(res);
1.1 provos 1285: }
1286:
1287: void
1.11 mouring 1288: monitor_apply_keystate(struct monitor *pmonitor)
1.1 provos 1289: {
1290: if (compat20) {
1291: set_newkeys(MODE_IN);
1292: set_newkeys(MODE_OUT);
1293: } else {
1294: packet_set_protocol_flags(child_state.ssh1protoflags);
1.15 markus 1295: packet_set_encryption_key(child_state.ssh1key,
1296: child_state.ssh1keylen, child_state.ssh1cipher);
1297: xfree(child_state.ssh1key);
1.1 provos 1298: }
1299:
1.15 markus 1300: /* for rc4 and other stateful ciphers */
1.1 provos 1301: packet_set_keycontext(MODE_OUT, child_state.keyout);
1302: xfree(child_state.keyout);
1303: packet_set_keycontext(MODE_IN, child_state.keyin);
1304: xfree(child_state.keyin);
1305:
1306: if (!compat20) {
1307: packet_set_iv(MODE_OUT, child_state.ivout);
1308: xfree(child_state.ivout);
1309: packet_set_iv(MODE_IN, child_state.ivin);
1310: xfree(child_state.ivin);
1311: }
1312:
1313: memcpy(&incoming_stream, &child_state.incoming,
1314: sizeof(incoming_stream));
1315: memcpy(&outgoing_stream, &child_state.outgoing,
1316: sizeof(outgoing_stream));
1.3 markus 1317:
1.1 provos 1318: /* Update with new address */
1.16 djm 1319: if (options.compression)
1320: mm_init_compression(pmonitor->m_zlib);
1.1 provos 1321:
1322: /* Network I/O buffers */
1323: /* XXX inefficient for large buffers, need: buffer_init_from_string */
1324: buffer_clear(&input);
1325: buffer_append(&input, child_state.input, child_state.ilen);
1326: memset(child_state.input, 0, child_state.ilen);
1327: xfree(child_state.input);
1328:
1329: buffer_clear(&output);
1330: buffer_append(&output, child_state.output, child_state.olen);
1331: memset(child_state.output, 0, child_state.olen);
1332: xfree(child_state.output);
1333: }
1334:
1.2 markus 1335: static Kex *
1.1 provos 1336: mm_get_kex(Buffer *m)
1337: {
1338: Kex *kex;
1339: void *blob;
1340: u_int bloblen;
1341:
1.75 djm 1342: kex = xcalloc(1, sizeof(*kex));
1.1 provos 1343: kex->session_id = buffer_get_string(m, &kex->session_id_len);
1.13 markus 1344: if ((session_id2 == NULL) ||
1345: (kex->session_id_len != session_id2_len) ||
1346: (memcmp(kex->session_id, session_id2, session_id2_len) != 0))
1347: fatal("mm_get_get: internal error: bad session id");
1.1 provos 1348: kex->we_need = buffer_get_int(m);
1.34 markus 1349: kex->kex[KEX_DH_GRP1_SHA1] = kexdh_server;
1.58 djm 1350: kex->kex[KEX_DH_GRP14_SHA1] = kexdh_server;
1.34 markus 1351: kex->kex[KEX_DH_GEX_SHA1] = kexgex_server;
1.69 djm 1352: kex->kex[KEX_DH_GEX_SHA256] = kexgex_server;
1.1 provos 1353: kex->server = 1;
1354: kex->hostkey_type = buffer_get_int(m);
1355: kex->kex_type = buffer_get_int(m);
1356: blob = buffer_get_string(m, &bloblen);
1357: buffer_init(&kex->my);
1358: buffer_append(&kex->my, blob, bloblen);
1359: xfree(blob);
1360: blob = buffer_get_string(m, &bloblen);
1361: buffer_init(&kex->peer);
1362: buffer_append(&kex->peer, blob, bloblen);
1363: xfree(blob);
1364: kex->done = 1;
1365: kex->flags = buffer_get_int(m);
1366: kex->client_version_string = buffer_get_string(m, NULL);
1367: kex->server_version_string = buffer_get_string(m, NULL);
1368: kex->load_host_key=&get_hostkey_by_type;
1369: kex->host_key_index=&get_hostkey_index;
1370:
1371: return (kex);
1372: }
1373:
1374: /* This function requries careful sanity checking */
1375:
1376: void
1.11 mouring 1377: mm_get_keystate(struct monitor *pmonitor)
1.1 provos 1378: {
1379: Buffer m;
1380: u_char *blob, *p;
1381: u_int bloblen, plen;
1.37 markus 1382: u_int32_t seqnr, packets;
1383: u_int64_t blocks;
1.1 provos 1384:
1.14 markus 1385: debug3("%s: Waiting for new keys", __func__);
1.1 provos 1386:
1387: buffer_init(&m);
1.11 mouring 1388: mm_request_receive_expect(pmonitor->m_sendfd, MONITOR_REQ_KEYEXPORT, &m);
1.1 provos 1389: if (!compat20) {
1390: child_state.ssh1protoflags = buffer_get_int(&m);
1391: child_state.ssh1cipher = buffer_get_int(&m);
1.15 markus 1392: child_state.ssh1key = buffer_get_string(&m,
1393: &child_state.ssh1keylen);
1.1 provos 1394: child_state.ivout = buffer_get_string(&m,
1395: &child_state.ivoutlen);
1396: child_state.ivin = buffer_get_string(&m, &child_state.ivinlen);
1397: goto skip;
1398: } else {
1399: /* Get the Kex for rekeying */
1.11 mouring 1400: *pmonitor->m_pkex = mm_get_kex(&m);
1.1 provos 1401: }
1402:
1403: blob = buffer_get_string(&m, &bloblen);
1404: current_keys[MODE_OUT] = mm_newkeys_from_blob(blob, bloblen);
1405: xfree(blob);
1406:
1.14 markus 1407: debug3("%s: Waiting for second key", __func__);
1.1 provos 1408: blob = buffer_get_string(&m, &bloblen);
1409: current_keys[MODE_IN] = mm_newkeys_from_blob(blob, bloblen);
1410: xfree(blob);
1.3 markus 1411:
1.1 provos 1412: /* Now get sequence numbers for the packets */
1.37 markus 1413: seqnr = buffer_get_int(&m);
1414: blocks = buffer_get_int64(&m);
1415: packets = buffer_get_int(&m);
1416: packet_set_state(MODE_OUT, seqnr, blocks, packets);
1417: seqnr = buffer_get_int(&m);
1418: blocks = buffer_get_int64(&m);
1419: packets = buffer_get_int(&m);
1420: packet_set_state(MODE_IN, seqnr, blocks, packets);
1.1 provos 1421:
1422: skip:
1423: /* Get the key context */
1424: child_state.keyout = buffer_get_string(&m, &child_state.keyoutlen);
1425: child_state.keyin = buffer_get_string(&m, &child_state.keyinlen);
1426:
1.14 markus 1427: debug3("%s: Getting compression state", __func__);
1.1 provos 1428: /* Get compression state */
1429: p = buffer_get_string(&m, &plen);
1430: if (plen != sizeof(child_state.outgoing))
1.14 markus 1431: fatal("%s: bad request size", __func__);
1.1 provos 1432: memcpy(&child_state.outgoing, p, sizeof(child_state.outgoing));
1433: xfree(p);
1434:
1435: p = buffer_get_string(&m, &plen);
1436: if (plen != sizeof(child_state.incoming))
1.14 markus 1437: fatal("%s: bad request size", __func__);
1.1 provos 1438: memcpy(&child_state.incoming, p, sizeof(child_state.incoming));
1439: xfree(p);
1440:
1441: /* Network I/O buffers */
1.14 markus 1442: debug3("%s: Getting Network I/O buffers", __func__);
1.1 provos 1443: child_state.input = buffer_get_string(&m, &child_state.ilen);
1444: child_state.output = buffer_get_string(&m, &child_state.olen);
1445:
1446: buffer_free(&m);
1447: }
1448:
1449:
1450: /* Allocation functions for zlib */
1451: void *
1452: mm_zalloc(struct mm_master *mm, u_int ncount, u_int size)
1453: {
1.30 markus 1454: size_t len = (size_t) size * ncount;
1.1 provos 1455: void *address;
1456:
1.23 millert 1457: if (len == 0 || ncount > SIZE_T_MAX / size)
1.18 deraadt 1458: fatal("%s: mm_zalloc(%u, %u)", __func__, ncount, size);
1459:
1460: address = mm_malloc(mm, len);
1.1 provos 1461:
1462: return (address);
1463: }
1464:
1465: void
1466: mm_zfree(struct mm_master *mm, void *address)
1467: {
1468: mm_free(mm, address);
1469: }
1470:
1471: void
1472: mm_init_compression(struct mm_master *mm)
1473: {
1474: outgoing_stream.zalloc = (alloc_func)mm_zalloc;
1475: outgoing_stream.zfree = (free_func)mm_zfree;
1476: outgoing_stream.opaque = mm;
1477:
1478: incoming_stream.zalloc = (alloc_func)mm_zalloc;
1479: incoming_stream.zfree = (free_func)mm_zfree;
1480: incoming_stream.opaque = mm;
1481: }
1482:
1483: /* XXX */
1484:
1485: #define FD_CLOSEONEXEC(x) do { \
1486: if (fcntl(x, F_SETFD, 1) == -1) \
1487: fatal("fcntl(%d, F_SETFD)", x); \
1488: } while (0)
1489:
1.2 markus 1490: static void
1.1 provos 1491: monitor_socketpair(int *pair)
1.3 markus 1492: {
1.1 provos 1493: if (socketpair(AF_UNIX, SOCK_STREAM, 0, pair) == -1)
1.14 markus 1494: fatal("%s: socketpair", __func__);
1.1 provos 1495: FD_CLOSEONEXEC(pair[0]);
1496: FD_CLOSEONEXEC(pair[1]);
1497: }
1498:
1499: #define MM_MEMSIZE 65536
1500:
1501: struct monitor *
1502: monitor_init(void)
1503: {
1504: struct monitor *mon;
1505: int pair[2];
1506:
1.75 djm 1507: mon = xcalloc(1, sizeof(*mon));
1.1 provos 1508:
1509: monitor_socketpair(pair);
1510:
1511: mon->m_recvfd = pair[0];
1512: mon->m_sendfd = pair[1];
1513:
1514: /* Used to share zlib space across processes */
1.16 djm 1515: if (options.compression) {
1516: mon->m_zback = mm_create(NULL, MM_MEMSIZE);
1517: mon->m_zlib = mm_create(mon->m_zback, 20 * MM_MEMSIZE);
1.1 provos 1518:
1.16 djm 1519: /* Compression needs to share state across borders */
1520: mm_init_compression(mon->m_zlib);
1521: }
1.1 provos 1522:
1523: return mon;
1524: }
1525:
1526: void
1527: monitor_reinit(struct monitor *mon)
1528: {
1529: int pair[2];
1530:
1531: monitor_socketpair(pair);
1532:
1533: mon->m_recvfd = pair[0];
1534: mon->m_sendfd = pair[1];
1535: }
1.46 markus 1536:
1537: #ifdef GSSAPI
1538: int
1.59 avsm 1539: mm_answer_gss_setup_ctx(int sock, Buffer *m)
1.46 markus 1540: {
1.59 avsm 1541: gss_OID_desc goid;
1.46 markus 1542: OM_uint32 major;
1543: u_int len;
1544:
1.59 avsm 1545: goid.elements = buffer_get_string(m, &len);
1546: goid.length = len;
1.46 markus 1547:
1.59 avsm 1548: major = ssh_gssapi_server_ctx(&gsscontext, &goid);
1.46 markus 1549:
1.59 avsm 1550: xfree(goid.elements);
1.46 markus 1551:
1552: buffer_clear(m);
1553: buffer_put_int(m, major);
1554:
1.64 stevesk 1555: mm_request_send(sock, MONITOR_ANS_GSSSETUP, m);
1.46 markus 1556:
1557: /* Now we have a context, enable the step */
1558: monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 1);
1559:
1560: return (0);
1561: }
1562:
1563: int
1.59 avsm 1564: mm_answer_gss_accept_ctx(int sock, Buffer *m)
1.46 markus 1565: {
1566: gss_buffer_desc in;
1567: gss_buffer_desc out = GSS_C_EMPTY_BUFFER;
1.64 stevesk 1568: OM_uint32 major, minor;
1.46 markus 1569: OM_uint32 flags = 0; /* GSI needs this */
1.47 deraadt 1570: u_int len;
1.46 markus 1571:
1.47 deraadt 1572: in.value = buffer_get_string(m, &len);
1573: in.length = len;
1.46 markus 1574: major = ssh_gssapi_accept_ctx(gsscontext, &in, &out, &flags);
1575: xfree(in.value);
1576:
1577: buffer_clear(m);
1578: buffer_put_int(m, major);
1579: buffer_put_string(m, out.value, out.length);
1580: buffer_put_int(m, flags);
1.59 avsm 1581: mm_request_send(sock, MONITOR_ANS_GSSSTEP, m);
1.46 markus 1582:
1583: gss_release_buffer(&minor, &out);
1584:
1.64 stevesk 1585: if (major == GSS_S_COMPLETE) {
1.46 markus 1586: monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 0);
1587: monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
1.52 markus 1588: monitor_permit(mon_dispatch, MONITOR_REQ_GSSCHECKMIC, 1);
1.46 markus 1589: }
1590: return (0);
1591: }
1592:
1593: int
1.59 avsm 1594: mm_answer_gss_checkmic(int sock, Buffer *m)
1.52 markus 1595: {
1596: gss_buffer_desc gssbuf, mic;
1597: OM_uint32 ret;
1598: u_int len;
1.54 djm 1599:
1.52 markus 1600: gssbuf.value = buffer_get_string(m, &len);
1601: gssbuf.length = len;
1602: mic.value = buffer_get_string(m, &len);
1603: mic.length = len;
1.54 djm 1604:
1.52 markus 1605: ret = ssh_gssapi_checkmic(gsscontext, &gssbuf, &mic);
1.54 djm 1606:
1.52 markus 1607: xfree(gssbuf.value);
1608: xfree(mic.value);
1.54 djm 1609:
1.52 markus 1610: buffer_clear(m);
1611: buffer_put_int(m, ret);
1.54 djm 1612:
1.59 avsm 1613: mm_request_send(sock, MONITOR_ANS_GSSCHECKMIC, m);
1.54 djm 1614:
1.52 markus 1615: if (!GSS_ERROR(ret))
1616: monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
1.54 djm 1617:
1.52 markus 1618: return (0);
1619: }
1620:
1621: int
1.59 avsm 1622: mm_answer_gss_userok(int sock, Buffer *m)
1.46 markus 1623: {
1624: int authenticated;
1625:
1626: authenticated = authctxt->valid && ssh_gssapi_userok(authctxt->user);
1627:
1628: buffer_clear(m);
1629: buffer_put_int(m, authenticated);
1630:
1631: debug3("%s: sending result %d", __func__, authenticated);
1.59 avsm 1632: mm_request_send(sock, MONITOR_ANS_GSSUSEROK, m);
1.46 markus 1633:
1.64 stevesk 1634: auth_method = "gssapi-with-mic";
1.46 markus 1635:
1636: /* Monitor loop will terminate if authenticated */
1637: return (authenticated);
1638: }
1639: #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