Annotation of src/usr.bin/ssh/monitor.c, Revision 1.85
1.85 ! deraadt 1: /* $OpenBSD: monitor.c,v 1.84 2006/07/26 13:57:17 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:
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: #ifdef SKEY
45: #include <skey.h>
46: #endif
47:
1.85 ! deraadt 48: #include "xmalloc.h"
1.1 provos 49: #include "ssh.h"
1.85 ! deraadt 50: #include "key.h"
! 51: #include "buffer.h"
! 52: #include "hostfile.h"
1.1 provos 53: #include "auth.h"
1.85 ! deraadt 54: #include "cipher.h"
1.1 provos 55: #include "kex.h"
56: #include "dh.h"
57: #include "zlib.h"
58: #include "packet.h"
59: #include "auth-options.h"
60: #include "sshpty.h"
61: #include "channels.h"
62: #include "session.h"
63: #include "sshlogin.h"
64: #include "canohost.h"
65: #include "log.h"
66: #include "servconf.h"
67: #include "monitor.h"
68: #include "monitor_mm.h"
1.85 ! deraadt 69: #ifdef GSSAPI
! 70: #include "ssh-gss.h"
! 71: #endif
1.1 provos 72: #include "monitor_wrap.h"
73: #include "monitor_fdpass.h"
74: #include "misc.h"
75: #include "compat.h"
76: #include "ssh2.h"
77:
1.46 markus 78: #ifdef GSSAPI
79: static Gssctxt *gsscontext = NULL;
80: #endif
81:
1.1 provos 82: /* Imports */
83: extern ServerOptions options;
84: extern u_int utmp_len;
85: extern Newkeys *current_keys[];
86: extern z_stream incoming_stream;
87: extern z_stream outgoing_stream;
88: extern u_char session_id[];
89: extern Buffer input, output;
90: extern Buffer auth_debug;
91: extern int auth_debug_init;
1.61 dtucker 92: extern Buffer loginmsg;
1.1 provos 93:
94: /* State exported from the child */
95:
96: struct {
97: z_stream incoming;
98: z_stream outgoing;
99: u_char *keyin;
100: u_int keyinlen;
101: u_char *keyout;
102: u_int keyoutlen;
103: u_char *ivin;
104: u_int ivinlen;
105: u_char *ivout;
106: u_int ivoutlen;
1.15 markus 107: u_char *ssh1key;
108: u_int ssh1keylen;
1.1 provos 109: int ssh1cipher;
110: int ssh1protoflags;
111: u_char *input;
112: u_int ilen;
113: u_char *output;
114: u_int olen;
115: } child_state;
116:
1.43 markus 117: /* Functions on the monitor that answer unprivileged requests */
1.1 provos 118:
119: int mm_answer_moduli(int, Buffer *);
120: int mm_answer_sign(int, Buffer *);
121: int mm_answer_pwnamallow(int, Buffer *);
1.10 djm 122: int mm_answer_auth2_read_banner(int, Buffer *);
1.1 provos 123: int mm_answer_authserv(int, Buffer *);
124: int mm_answer_authpassword(int, Buffer *);
125: int mm_answer_bsdauthquery(int, Buffer *);
126: int mm_answer_bsdauthrespond(int, Buffer *);
127: int mm_answer_skeyquery(int, Buffer *);
128: int mm_answer_skeyrespond(int, Buffer *);
129: int mm_answer_keyallowed(int, Buffer *);
130: int mm_answer_keyverify(int, Buffer *);
131: int mm_answer_pty(int, Buffer *);
132: int mm_answer_pty_cleanup(int, Buffer *);
133: int mm_answer_term(int, Buffer *);
134: int mm_answer_rsa_keyallowed(int, Buffer *);
135: int mm_answer_rsa_challenge(int, Buffer *);
136: int mm_answer_rsa_response(int, Buffer *);
137: int mm_answer_sesskey(int, Buffer *);
138: int mm_answer_sessid(int, Buffer *);
139:
1.46 markus 140: #ifdef GSSAPI
141: int mm_answer_gss_setup_ctx(int, Buffer *);
142: int mm_answer_gss_accept_ctx(int, Buffer *);
143: int mm_answer_gss_userok(int, Buffer *);
1.52 markus 144: int mm_answer_gss_checkmic(int, Buffer *);
1.46 markus 145: #endif
1.25 itojun 146:
1.1 provos 147: static Authctxt *authctxt;
148: static BIGNUM *ssh1_challenge = NULL; /* used for ssh1 rsa auth */
149:
150: /* local state for key verify */
151: static u_char *key_blob = NULL;
152: static u_int key_bloblen = 0;
153: static int key_blobtype = MM_NOKEY;
1.26 markus 154: static char *hostbased_cuser = NULL;
155: static char *hostbased_chost = NULL;
1.1 provos 156: static char *auth_method = "unknown";
1.44 markus 157: static u_int session_id2_len = 0;
1.13 markus 158: static u_char *session_id2 = NULL;
1.40 markus 159: static pid_t monitor_child_pid;
1.1 provos 160:
161: struct mon_table {
162: enum monitor_reqtype type;
163: int flags;
164: int (*f)(int, Buffer *);
165: };
166:
167: #define MON_ISAUTH 0x0004 /* Required for Authentication */
168: #define MON_AUTHDECIDE 0x0008 /* Decides Authentication */
169: #define MON_ONCE 0x0010 /* Disable after calling */
1.77 dtucker 170: #define MON_ALOG 0x0020 /* Log auth attempt without authenticating */
1.1 provos 171:
172: #define MON_AUTH (MON_ISAUTH|MON_AUTHDECIDE)
173:
174: #define MON_PERMIT 0x1000 /* Request is permitted */
175:
176: struct mon_table mon_dispatch_proto20[] = {
177: {MONITOR_REQ_MODULI, MON_ONCE, mm_answer_moduli},
178: {MONITOR_REQ_SIGN, MON_ONCE, mm_answer_sign},
179: {MONITOR_REQ_PWNAM, MON_ONCE, mm_answer_pwnamallow},
180: {MONITOR_REQ_AUTHSERV, MON_ONCE, mm_answer_authserv},
1.10 djm 181: {MONITOR_REQ_AUTH2_READ_BANNER, MON_ONCE, mm_answer_auth2_read_banner},
1.1 provos 182: {MONITOR_REQ_AUTHPASSWORD, MON_AUTH, mm_answer_authpassword},
183: #ifdef BSD_AUTH
184: {MONITOR_REQ_BSDAUTHQUERY, MON_ISAUTH, mm_answer_bsdauthquery},
1.66 stevesk 185: {MONITOR_REQ_BSDAUTHRESPOND, MON_AUTH, mm_answer_bsdauthrespond},
1.1 provos 186: #endif
187: #ifdef SKEY
188: {MONITOR_REQ_SKEYQUERY, MON_ISAUTH, mm_answer_skeyquery},
189: {MONITOR_REQ_SKEYRESPOND, MON_AUTH, mm_answer_skeyrespond},
190: #endif
191: {MONITOR_REQ_KEYALLOWED, MON_ISAUTH, mm_answer_keyallowed},
192: {MONITOR_REQ_KEYVERIFY, MON_AUTH, mm_answer_keyverify},
1.46 markus 193: #ifdef GSSAPI
194: {MONITOR_REQ_GSSSETUP, MON_ISAUTH, mm_answer_gss_setup_ctx},
195: {MONITOR_REQ_GSSSTEP, MON_ISAUTH, mm_answer_gss_accept_ctx},
196: {MONITOR_REQ_GSSUSEROK, MON_AUTH, mm_answer_gss_userok},
1.52 markus 197: {MONITOR_REQ_GSSCHECKMIC, MON_ISAUTH, mm_answer_gss_checkmic},
1.46 markus 198: #endif
1.1 provos 199: {0, 0, NULL}
200: };
201:
202: struct mon_table mon_dispatch_postauth20[] = {
203: {MONITOR_REQ_MODULI, 0, mm_answer_moduli},
204: {MONITOR_REQ_SIGN, 0, mm_answer_sign},
205: {MONITOR_REQ_PTY, 0, mm_answer_pty},
206: {MONITOR_REQ_PTYCLEANUP, 0, mm_answer_pty_cleanup},
207: {MONITOR_REQ_TERM, 0, mm_answer_term},
208: {0, 0, NULL}
209: };
210:
211: struct mon_table mon_dispatch_proto15[] = {
212: {MONITOR_REQ_PWNAM, MON_ONCE, mm_answer_pwnamallow},
213: {MONITOR_REQ_SESSKEY, MON_ONCE, mm_answer_sesskey},
214: {MONITOR_REQ_SESSID, MON_ONCE, mm_answer_sessid},
215: {MONITOR_REQ_AUTHPASSWORD, MON_AUTH, mm_answer_authpassword},
1.77 dtucker 216: {MONITOR_REQ_RSAKEYALLOWED, MON_ISAUTH|MON_ALOG, mm_answer_rsa_keyallowed},
217: {MONITOR_REQ_KEYALLOWED, MON_ISAUTH|MON_ALOG, mm_answer_keyallowed},
1.1 provos 218: {MONITOR_REQ_RSACHALLENGE, MON_ONCE, mm_answer_rsa_challenge},
219: {MONITOR_REQ_RSARESPONSE, MON_ONCE|MON_AUTHDECIDE, mm_answer_rsa_response},
220: #ifdef BSD_AUTH
221: {MONITOR_REQ_BSDAUTHQUERY, MON_ISAUTH, mm_answer_bsdauthquery},
1.66 stevesk 222: {MONITOR_REQ_BSDAUTHRESPOND, MON_AUTH, mm_answer_bsdauthrespond},
1.1 provos 223: #endif
224: #ifdef SKEY
225: {MONITOR_REQ_SKEYQUERY, MON_ISAUTH, mm_answer_skeyquery},
226: {MONITOR_REQ_SKEYRESPOND, MON_AUTH, mm_answer_skeyrespond},
227: #endif
228: {0, 0, NULL}
229: };
230:
231: struct mon_table mon_dispatch_postauth15[] = {
232: {MONITOR_REQ_PTY, MON_ONCE, mm_answer_pty},
233: {MONITOR_REQ_PTYCLEANUP, MON_ONCE, mm_answer_pty_cleanup},
234: {MONITOR_REQ_TERM, 0, mm_answer_term},
235: {0, 0, NULL}
236: };
237:
238: struct mon_table *mon_dispatch;
239:
240: /* Specifies if a certain message is allowed at the moment */
241:
242: static void
243: monitor_permit(struct mon_table *ent, enum monitor_reqtype type, int permit)
244: {
245: while (ent->f != NULL) {
246: if (ent->type == type) {
247: ent->flags &= ~MON_PERMIT;
248: ent->flags |= permit ? MON_PERMIT : 0;
249: return;
250: }
251: ent++;
252: }
253: }
254:
255: static void
256: monitor_permit_authentications(int permit)
257: {
258: struct mon_table *ent = mon_dispatch;
259:
260: while (ent->f != NULL) {
261: if (ent->flags & MON_AUTH) {
262: ent->flags &= ~MON_PERMIT;
263: ent->flags |= permit ? MON_PERMIT : 0;
264: }
265: ent++;
266: }
267: }
268:
1.50 markus 269: void
270: monitor_child_preauth(Authctxt *_authctxt, struct monitor *pmonitor)
1.1 provos 271: {
272: struct mon_table *ent;
273: int authenticated = 0;
274:
275: debug3("preauth child monitor started");
276:
1.50 markus 277: authctxt = _authctxt;
278: memset(authctxt, 0, sizeof(*authctxt));
279:
1.1 provos 280: if (compat20) {
281: mon_dispatch = mon_dispatch_proto20;
282:
283: /* Permit requests for moduli and signatures */
284: monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
285: monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
286: } else {
287: mon_dispatch = mon_dispatch_proto15;
288:
289: monitor_permit(mon_dispatch, MONITOR_REQ_SESSKEY, 1);
290: }
291:
292: /* The first few requests do not require asynchronous access */
293: while (!authenticated) {
1.77 dtucker 294: auth_method = "unknown";
1.11 mouring 295: authenticated = monitor_read(pmonitor, mon_dispatch, &ent);
1.1 provos 296: if (authenticated) {
297: if (!(ent->flags & MON_AUTHDECIDE))
298: fatal("%s: unexpected authentication from %d",
1.14 markus 299: __func__, ent->type);
1.1 provos 300: if (authctxt->pw->pw_uid == 0 &&
301: !auth_root_allowed(auth_method))
302: authenticated = 0;
303: }
304:
1.77 dtucker 305: if (ent->flags & (MON_AUTHDECIDE|MON_ALOG)) {
1.1 provos 306: auth_log(authctxt, authenticated, auth_method,
307: compat20 ? " ssh2" : "");
308: if (!authenticated)
309: authctxt->failures++;
310: }
311: }
312:
313: if (!authctxt->valid)
1.14 markus 314: fatal("%s: authenticated invalid user", __func__);
1.77 dtucker 315: if (strcmp(auth_method, "unknown") == 0)
316: fatal("%s: authentication method name unknown", __func__);
1.1 provos 317:
318: debug("%s: %s has been authenticated by privileged process",
1.14 markus 319: __func__, authctxt->user);
1.1 provos 320:
1.11 mouring 321: mm_get_keystate(pmonitor);
1.1 provos 322: }
323:
1.40 markus 324: static void
325: monitor_set_child_handler(pid_t pid)
326: {
327: monitor_child_pid = pid;
328: }
329:
330: static void
1.59 avsm 331: monitor_child_handler(int sig)
1.40 markus 332: {
1.59 avsm 333: kill(monitor_child_pid, sig);
1.40 markus 334: }
335:
1.1 provos 336: void
1.11 mouring 337: monitor_child_postauth(struct monitor *pmonitor)
1.1 provos 338: {
1.40 markus 339: monitor_set_child_handler(pmonitor->m_pid);
340: signal(SIGHUP, &monitor_child_handler);
341: signal(SIGTERM, &monitor_child_handler);
342:
1.1 provos 343: if (compat20) {
344: mon_dispatch = mon_dispatch_postauth20;
345:
346: /* Permit requests for moduli and signatures */
347: monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
348: monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
349: monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1);
350: } else {
351: mon_dispatch = mon_dispatch_postauth15;
352: monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1);
353: }
354: if (!no_pty_flag) {
355: monitor_permit(mon_dispatch, MONITOR_REQ_PTY, 1);
356: monitor_permit(mon_dispatch, MONITOR_REQ_PTYCLEANUP, 1);
357: }
358:
359: for (;;)
1.11 mouring 360: monitor_read(pmonitor, mon_dispatch, NULL);
1.1 provos 361: }
362:
363: void
1.11 mouring 364: monitor_sync(struct monitor *pmonitor)
1.1 provos 365: {
1.16 djm 366: if (options.compression) {
367: /* The member allocation is not visible, so sync it */
368: mm_share_sync(&pmonitor->m_zlib, &pmonitor->m_zback);
369: }
1.1 provos 370: }
371:
372: int
1.11 mouring 373: monitor_read(struct monitor *pmonitor, struct mon_table *ent,
1.1 provos 374: struct mon_table **pent)
375: {
376: Buffer m;
377: int ret;
378: u_char type;
379:
380: buffer_init(&m);
381:
1.11 mouring 382: mm_request_receive(pmonitor->m_sendfd, &m);
1.1 provos 383: type = buffer_get_char(&m);
384:
1.14 markus 385: debug3("%s: checking request %d", __func__, type);
1.1 provos 386:
387: while (ent->f != NULL) {
388: if (ent->type == type)
389: break;
390: ent++;
391: }
392:
393: if (ent->f != NULL) {
394: if (!(ent->flags & MON_PERMIT))
1.14 markus 395: fatal("%s: unpermitted request %d", __func__,
1.1 provos 396: type);
1.11 mouring 397: ret = (*ent->f)(pmonitor->m_sendfd, &m);
1.1 provos 398: buffer_free(&m);
399:
400: /* The child may use this request only once, disable it */
401: if (ent->flags & MON_ONCE) {
1.14 markus 402: debug2("%s: %d used once, disabling now", __func__,
1.1 provos 403: type);
404: ent->flags &= ~MON_PERMIT;
405: }
406:
407: if (pent != NULL)
408: *pent = ent;
1.3 markus 409:
1.1 provos 410: return ret;
411: }
412:
1.14 markus 413: fatal("%s: unsupported request: %d", __func__, type);
1.1 provos 414:
415: /* NOTREACHED */
416: return (-1);
417: }
418:
419: /* allowed key state */
420: static int
421: monitor_allowed_key(u_char *blob, u_int bloblen)
422: {
423: /* make sure key is allowed */
424: if (key_blob == NULL || key_bloblen != bloblen ||
425: memcmp(key_blob, blob, key_bloblen))
426: return (0);
427: return (1);
428: }
429:
430: static void
431: monitor_reset_key_state(void)
432: {
433: /* reset state */
434: if (key_blob != NULL)
435: xfree(key_blob);
436: if (hostbased_cuser != NULL)
437: xfree(hostbased_cuser);
438: if (hostbased_chost != NULL)
439: xfree(hostbased_chost);
440: key_blob = NULL;
441: key_bloblen = 0;
442: key_blobtype = MM_NOKEY;
443: hostbased_cuser = NULL;
444: hostbased_chost = NULL;
445: }
446:
447: int
1.59 avsm 448: mm_answer_moduli(int sock, Buffer *m)
1.1 provos 449: {
450: DH *dh;
451: int min, want, max;
452:
453: min = buffer_get_int(m);
454: want = buffer_get_int(m);
455: max = buffer_get_int(m);
456:
457: debug3("%s: got parameters: %d %d %d",
1.14 markus 458: __func__, min, want, max);
1.1 provos 459: /* We need to check here, too, in case the child got corrupted */
460: if (max < min || want < min || max < want)
461: fatal("%s: bad parameters: %d %d %d",
1.14 markus 462: __func__, min, want, max);
1.1 provos 463:
464: buffer_clear(m);
465:
466: dh = choose_dh(min, want, max);
467: if (dh == NULL) {
468: buffer_put_char(m, 0);
469: return (0);
470: } else {
471: /* Send first bignum */
472: buffer_put_char(m, 1);
473: buffer_put_bignum2(m, dh->p);
474: buffer_put_bignum2(m, dh->g);
1.3 markus 475:
1.1 provos 476: DH_free(dh);
477: }
1.59 avsm 478: mm_request_send(sock, MONITOR_ANS_MODULI, m);
1.1 provos 479: return (0);
480: }
481:
482: int
1.59 avsm 483: mm_answer_sign(int sock, Buffer *m)
1.1 provos 484: {
485: Key *key;
486: u_char *p;
487: u_char *signature;
488: u_int siglen, datlen;
489: int keyid;
1.3 markus 490:
1.14 markus 491: debug3("%s", __func__);
1.1 provos 492:
1.3 markus 493: keyid = buffer_get_int(m);
494: p = buffer_get_string(m, &datlen);
1.1 provos 495:
1.69 djm 496: /*
1.71 deraadt 497: * Supported KEX types will only return SHA1 (20 byte) or
1.69 djm 498: * SHA256 (32 byte) hashes
499: */
500: if (datlen != 20 && datlen != 32)
1.19 deraadt 501: fatal("%s: data length incorrect: %u", __func__, datlen);
1.1 provos 502:
1.13 markus 503: /* save session id, it will be passed on the first call */
504: if (session_id2_len == 0) {
505: session_id2_len = datlen;
506: session_id2 = xmalloc(session_id2_len);
507: memcpy(session_id2, p, session_id2_len);
508: }
509:
1.1 provos 510: if ((key = get_hostkey_by_index(keyid)) == NULL)
1.14 markus 511: fatal("%s: no hostkey from index %d", __func__, keyid);
1.1 provos 512: if (key_sign(key, &signature, &siglen, p, datlen) < 0)
1.14 markus 513: fatal("%s: key_sign failed", __func__);
1.1 provos 514:
1.19 deraadt 515: debug3("%s: signature %p(%u)", __func__, signature, siglen);
1.1 provos 516:
517: buffer_clear(m);
518: buffer_put_string(m, signature, siglen);
519:
520: xfree(p);
521: xfree(signature);
522:
1.59 avsm 523: mm_request_send(sock, MONITOR_ANS_SIGN, m);
1.1 provos 524:
525: /* Turn on permissions for getpwnam */
526: monitor_permit(mon_dispatch, MONITOR_REQ_PWNAM, 1);
527:
528: return (0);
529: }
530:
531: /* Retrieves the password entry and also checks if the user is permitted */
532:
533: int
1.59 avsm 534: mm_answer_pwnamallow(int sock, Buffer *m)
1.1 provos 535: {
1.60 dtucker 536: char *username;
1.1 provos 537: struct passwd *pwent;
538: int allowed = 0;
1.3 markus 539:
1.14 markus 540: debug3("%s", __func__);
1.1 provos 541:
542: if (authctxt->attempt++ != 0)
1.14 markus 543: fatal("%s: multiple attempts for getpwnam", __func__);
1.1 provos 544:
1.60 dtucker 545: username = buffer_get_string(m, NULL);
1.1 provos 546:
1.60 dtucker 547: pwent = getpwnamallow(username);
1.1 provos 548:
1.60 dtucker 549: authctxt->user = xstrdup(username);
550: setproctitle("%s [priv]", pwent ? username : "unknown");
551: xfree(username);
1.1 provos 552:
553: buffer_clear(m);
554:
555: if (pwent == NULL) {
556: buffer_put_char(m, 0);
1.53 djm 557: authctxt->pw = fakepw();
1.1 provos 558: goto out;
559: }
560:
561: allowed = 1;
1.4 markus 562: authctxt->pw = pwent;
1.1 provos 563: authctxt->valid = 1;
564:
565: buffer_put_char(m, 1);
566: buffer_put_string(m, pwent, sizeof(struct passwd));
567: buffer_put_cstring(m, pwent->pw_name);
568: buffer_put_cstring(m, "*");
569: buffer_put_cstring(m, pwent->pw_gecos);
570: buffer_put_cstring(m, pwent->pw_class);
571: buffer_put_cstring(m, pwent->pw_dir);
572: buffer_put_cstring(m, pwent->pw_shell);
573:
574: out:
1.14 markus 575: debug3("%s: sending MONITOR_ANS_PWNAM: %d", __func__, allowed);
1.59 avsm 576: mm_request_send(sock, MONITOR_ANS_PWNAM, m);
1.1 provos 577:
578: /* For SSHv1 allow authentication now */
579: if (!compat20)
580: monitor_permit_authentications(1);
1.10 djm 581: else {
1.1 provos 582: /* Allow service/style information on the auth context */
583: monitor_permit(mon_dispatch, MONITOR_REQ_AUTHSERV, 1);
1.10 djm 584: monitor_permit(mon_dispatch, MONITOR_REQ_AUTH2_READ_BANNER, 1);
585: }
586:
587:
588: return (0);
589: }
590:
1.59 avsm 591: int mm_answer_auth2_read_banner(int sock, Buffer *m)
1.10 djm 592: {
593: char *banner;
594:
595: buffer_clear(m);
596: banner = auth2_read_banner();
597: buffer_put_cstring(m, banner != NULL ? banner : "");
1.59 avsm 598: mm_request_send(sock, MONITOR_ANS_AUTH2_READ_BANNER, m);
1.1 provos 599:
1.10 djm 600: if (banner != NULL)
1.21 deraadt 601: xfree(banner);
1.1 provos 602:
603: return (0);
604: }
605:
606: int
1.59 avsm 607: mm_answer_authserv(int sock, Buffer *m)
1.1 provos 608: {
609: monitor_permit_authentications(1);
610:
611: authctxt->service = buffer_get_string(m, NULL);
612: authctxt->style = buffer_get_string(m, NULL);
1.6 stevesk 613: debug3("%s: service=%s, style=%s",
1.14 markus 614: __func__, authctxt->service, authctxt->style);
1.6 stevesk 615:
1.1 provos 616: if (strlen(authctxt->style) == 0) {
617: xfree(authctxt->style);
618: authctxt->style = NULL;
619: }
620:
621: return (0);
622: }
623:
624: int
1.59 avsm 625: mm_answer_authpassword(int sock, Buffer *m)
1.1 provos 626: {
627: static int call_count;
628: char *passwd;
1.22 stevesk 629: int authenticated;
630: u_int plen;
1.1 provos 631:
632: passwd = buffer_get_string(m, &plen);
633: /* Only authenticate if the context is valid */
1.12 markus 634: authenticated = options.password_authentication &&
1.48 markus 635: auth_password(authctxt, passwd);
1.1 provos 636: memset(passwd, 0, strlen(passwd));
637: xfree(passwd);
638:
639: buffer_clear(m);
640: buffer_put_int(m, authenticated);
641:
1.14 markus 642: debug3("%s: sending result %d", __func__, authenticated);
1.59 avsm 643: mm_request_send(sock, MONITOR_ANS_AUTHPASSWORD, m);
1.1 provos 644:
645: call_count++;
646: if (plen == 0 && call_count == 1)
647: auth_method = "none";
648: else
649: auth_method = "password";
650:
651: /* Causes monitor loop to terminate if authenticated */
652: return (authenticated);
653: }
654:
655: #ifdef BSD_AUTH
656: int
1.59 avsm 657: mm_answer_bsdauthquery(int sock, Buffer *m)
1.1 provos 658: {
659: char *name, *infotxt;
660: u_int numprompts;
661: u_int *echo_on;
662: char **prompts;
1.31 markus 663: u_int success;
1.1 provos 664:
1.31 markus 665: success = bsdauth_query(authctxt, &name, &infotxt, &numprompts,
666: &prompts, &echo_on) < 0 ? 0 : 1;
1.1 provos 667:
668: buffer_clear(m);
1.31 markus 669: buffer_put_int(m, success);
670: if (success)
1.1 provos 671: buffer_put_cstring(m, prompts[0]);
672:
1.31 markus 673: debug3("%s: sending challenge success: %u", __func__, success);
1.59 avsm 674: mm_request_send(sock, MONITOR_ANS_BSDAUTHQUERY, m);
1.1 provos 675:
1.31 markus 676: if (success) {
1.1 provos 677: xfree(name);
678: xfree(infotxt);
679: xfree(prompts);
680: xfree(echo_on);
681: }
682:
683: return (0);
684: }
685:
686: int
1.59 avsm 687: mm_answer_bsdauthrespond(int sock, Buffer *m)
1.1 provos 688: {
689: char *response;
690: int authok;
691:
692: if (authctxt->as == 0)
1.14 markus 693: fatal("%s: no bsd auth session", __func__);
1.1 provos 694:
695: response = buffer_get_string(m, NULL);
1.12 markus 696: authok = options.challenge_response_authentication &&
697: auth_userresponse(authctxt->as, response, 0);
1.1 provos 698: authctxt->as = NULL;
1.14 markus 699: debug3("%s: <%s> = <%d>", __func__, response, authok);
1.1 provos 700: xfree(response);
701:
702: buffer_clear(m);
703: buffer_put_int(m, authok);
704:
1.14 markus 705: debug3("%s: sending authenticated: %d", __func__, authok);
1.59 avsm 706: mm_request_send(sock, MONITOR_ANS_BSDAUTHRESPOND, m);
1.1 provos 707:
708: auth_method = "bsdauth";
709:
710: return (authok != 0);
711: }
712: #endif
713:
714: #ifdef SKEY
715: int
1.59 avsm 716: mm_answer_skeyquery(int sock, Buffer *m)
1.1 provos 717: {
718: struct skey skey;
719: char challenge[1024];
1.31 markus 720: u_int success;
1.1 provos 721:
1.31 markus 722: success = skeychallenge(&skey, authctxt->user, challenge) < 0 ? 0 : 1;
1.1 provos 723:
724: buffer_clear(m);
1.31 markus 725: buffer_put_int(m, success);
726: if (success)
1.1 provos 727: buffer_put_cstring(m, challenge);
728:
1.31 markus 729: debug3("%s: sending challenge success: %u", __func__, success);
1.59 avsm 730: mm_request_send(sock, MONITOR_ANS_SKEYQUERY, m);
1.1 provos 731:
732: return (0);
733: }
734:
735: int
1.59 avsm 736: mm_answer_skeyrespond(int sock, Buffer *m)
1.1 provos 737: {
738: char *response;
739: int authok;
740:
741: response = buffer_get_string(m, NULL);
742:
1.12 markus 743: authok = (options.challenge_response_authentication &&
744: authctxt->valid &&
1.1 provos 745: skey_haskey(authctxt->pw->pw_name) == 0 &&
746: skey_passcheck(authctxt->pw->pw_name, response) != -1);
747:
748: xfree(response);
749:
750: buffer_clear(m);
751: buffer_put_int(m, authok);
752:
1.14 markus 753: debug3("%s: sending authenticated: %d", __func__, authok);
1.59 avsm 754: mm_request_send(sock, MONITOR_ANS_SKEYRESPOND, m);
1.1 provos 755:
756: auth_method = "skey";
757:
758: return (authok != 0);
759: }
760: #endif
761:
1.2 markus 762: static void
1.1 provos 763: mm_append_debug(Buffer *m)
764: {
765: if (auth_debug_init && buffer_len(&auth_debug)) {
1.14 markus 766: debug3("%s: Appending debug messages for child", __func__);
1.1 provos 767: buffer_append(m, buffer_ptr(&auth_debug),
768: buffer_len(&auth_debug));
769: buffer_clear(&auth_debug);
770: }
771: }
772:
773: int
1.59 avsm 774: mm_answer_keyallowed(int sock, Buffer *m)
1.1 provos 775: {
776: Key *key;
1.26 markus 777: char *cuser, *chost;
778: u_char *blob;
1.1 provos 779: u_int bloblen;
780: enum mm_keytype type = 0;
781: int allowed = 0;
782:
1.14 markus 783: debug3("%s entering", __func__);
1.3 markus 784:
1.1 provos 785: type = buffer_get_int(m);
786: cuser = buffer_get_string(m, NULL);
787: chost = buffer_get_string(m, NULL);
788: blob = buffer_get_string(m, &bloblen);
789:
790: key = key_from_blob(blob, bloblen);
791:
792: if ((compat20 && type == MM_RSAHOSTKEY) ||
793: (!compat20 && type != MM_RSAHOSTKEY))
1.14 markus 794: fatal("%s: key type and protocol mismatch", __func__);
1.1 provos 795:
1.14 markus 796: debug3("%s: key_from_blob: %p", __func__, key);
1.1 provos 797:
1.51 djm 798: if (key != NULL && authctxt->valid) {
1.63 deraadt 799: switch (type) {
1.1 provos 800: case MM_USERKEY:
1.12 markus 801: allowed = options.pubkey_authentication &&
802: user_key_allowed(authctxt->pw, key);
1.77 dtucker 803: auth_method = "publickey";
1.1 provos 804: break;
805: case MM_HOSTKEY:
1.12 markus 806: allowed = options.hostbased_authentication &&
807: hostbased_key_allowed(authctxt->pw,
1.1 provos 808: cuser, chost, key);
1.77 dtucker 809: auth_method = "hostbased";
1.1 provos 810: break;
811: case MM_RSAHOSTKEY:
812: key->type = KEY_RSA1; /* XXX */
1.12 markus 813: allowed = options.rhosts_rsa_authentication &&
814: auth_rhosts_rsa_key_allowed(authctxt->pw,
1.1 provos 815: cuser, chost, key);
1.77 dtucker 816: auth_method = "rsa";
1.1 provos 817: break;
818: default:
1.14 markus 819: fatal("%s: unknown key type %d", __func__, type);
1.1 provos 820: break;
821: }
1.33 markus 822: }
823: if (key != NULL)
1.1 provos 824: key_free(key);
825:
826: /* clear temporarily storage (used by verify) */
827: monitor_reset_key_state();
828:
829: if (allowed) {
830: /* Save temporarily for comparison in verify */
831: key_blob = blob;
832: key_bloblen = bloblen;
833: key_blobtype = type;
834: hostbased_cuser = cuser;
835: hostbased_chost = chost;
1.72 djm 836: } else {
1.77 dtucker 837: /* Log failed attempt */
838: auth_log(authctxt, 0, auth_method, compat20 ? " ssh2" : "");
1.72 djm 839: xfree(blob);
840: xfree(cuser);
841: xfree(chost);
1.1 provos 842: }
843:
844: debug3("%s: key %p is %s",
1.14 markus 845: __func__, key, allowed ? "allowed" : "disallowed");
1.1 provos 846:
847: buffer_clear(m);
848: buffer_put_int(m, allowed);
1.32 markus 849: buffer_put_int(m, forced_command != NULL);
1.1 provos 850:
851: mm_append_debug(m);
852:
1.59 avsm 853: mm_request_send(sock, MONITOR_ANS_KEYALLOWED, m);
1.1 provos 854:
855: if (type == MM_RSAHOSTKEY)
856: monitor_permit(mon_dispatch, MONITOR_REQ_RSACHALLENGE, allowed);
857:
858: return (0);
859: }
860:
861: static int
862: monitor_valid_userblob(u_char *data, u_int datalen)
863: {
864: Buffer b;
1.26 markus 865: char *p;
1.1 provos 866: u_int len;
867: int fail = 0;
868:
869: buffer_init(&b);
870: buffer_append(&b, data, datalen);
1.3 markus 871:
1.1 provos 872: if (datafellows & SSH_OLD_SESSIONID) {
1.13 markus 873: p = buffer_ptr(&b);
874: len = buffer_len(&b);
875: if ((session_id2 == NULL) ||
876: (len < session_id2_len) ||
877: (memcmp(p, session_id2, session_id2_len) != 0))
878: fail++;
1.1 provos 879: buffer_consume(&b, session_id2_len);
880: } else {
1.13 markus 881: p = buffer_get_string(&b, &len);
882: if ((session_id2 == NULL) ||
883: (len != session_id2_len) ||
884: (memcmp(p, session_id2, session_id2_len) != 0))
1.1 provos 885: fail++;
1.13 markus 886: xfree(p);
1.1 provos 887: }
888: if (buffer_get_char(&b) != SSH2_MSG_USERAUTH_REQUEST)
889: fail++;
890: p = buffer_get_string(&b, NULL);
891: if (strcmp(authctxt->user, p) != 0) {
1.38 itojun 892: logit("wrong user name passed to monitor: expected %s != %.100s",
1.1 provos 893: authctxt->user, p);
894: fail++;
895: }
896: xfree(p);
897: buffer_skip_string(&b);
898: if (datafellows & SSH_BUG_PKAUTH) {
899: if (!buffer_get_char(&b))
900: fail++;
901: } else {
902: p = buffer_get_string(&b, NULL);
903: if (strcmp("publickey", p) != 0)
904: fail++;
905: xfree(p);
906: if (!buffer_get_char(&b))
907: fail++;
908: buffer_skip_string(&b);
909: }
910: buffer_skip_string(&b);
911: if (buffer_len(&b) != 0)
912: fail++;
913: buffer_free(&b);
914: return (fail == 0);
915: }
916:
917: static int
1.26 markus 918: monitor_valid_hostbasedblob(u_char *data, u_int datalen, char *cuser,
919: char *chost)
1.1 provos 920: {
921: Buffer b;
1.26 markus 922: char *p;
1.1 provos 923: u_int len;
924: int fail = 0;
925:
926: buffer_init(&b);
927: buffer_append(&b, data, datalen);
1.3 markus 928:
1.13 markus 929: p = buffer_get_string(&b, &len);
930: if ((session_id2 == NULL) ||
931: (len != session_id2_len) ||
932: (memcmp(p, session_id2, session_id2_len) != 0))
1.1 provos 933: fail++;
1.13 markus 934: xfree(p);
935:
1.1 provos 936: if (buffer_get_char(&b) != SSH2_MSG_USERAUTH_REQUEST)
937: fail++;
938: p = buffer_get_string(&b, NULL);
939: if (strcmp(authctxt->user, p) != 0) {
1.38 itojun 940: logit("wrong user name passed to monitor: expected %s != %.100s",
1.1 provos 941: authctxt->user, p);
942: fail++;
943: }
944: xfree(p);
945: buffer_skip_string(&b); /* service */
946: p = buffer_get_string(&b, NULL);
947: if (strcmp(p, "hostbased") != 0)
948: fail++;
949: xfree(p);
950: buffer_skip_string(&b); /* pkalg */
951: buffer_skip_string(&b); /* pkblob */
952:
953: /* verify client host, strip trailing dot if necessary */
954: p = buffer_get_string(&b, NULL);
955: if (((len = strlen(p)) > 0) && p[len - 1] == '.')
956: p[len - 1] = '\0';
957: if (strcmp(p, chost) != 0)
958: fail++;
959: xfree(p);
960:
961: /* verify client user */
962: p = buffer_get_string(&b, NULL);
963: if (strcmp(p, cuser) != 0)
964: fail++;
965: xfree(p);
966:
967: if (buffer_len(&b) != 0)
968: fail++;
969: buffer_free(&b);
970: return (fail == 0);
971: }
972:
973: int
1.59 avsm 974: mm_answer_keyverify(int sock, Buffer *m)
1.1 provos 975: {
976: Key *key;
977: u_char *signature, *data, *blob;
978: u_int signaturelen, datalen, bloblen;
979: int verified = 0;
980: int valid_data = 0;
981:
982: blob = buffer_get_string(m, &bloblen);
983: signature = buffer_get_string(m, &signaturelen);
984: data = buffer_get_string(m, &datalen);
985:
986: if (hostbased_cuser == NULL || hostbased_chost == NULL ||
1.8 mouring 987: !monitor_allowed_key(blob, bloblen))
1.14 markus 988: fatal("%s: bad key, not previously allowed", __func__);
1.1 provos 989:
990: key = key_from_blob(blob, bloblen);
991: if (key == NULL)
1.14 markus 992: fatal("%s: bad public key blob", __func__);
1.1 provos 993:
994: switch (key_blobtype) {
995: case MM_USERKEY:
996: valid_data = monitor_valid_userblob(data, datalen);
997: break;
998: case MM_HOSTKEY:
999: valid_data = monitor_valid_hostbasedblob(data, datalen,
1000: hostbased_cuser, hostbased_chost);
1001: break;
1002: default:
1003: valid_data = 0;
1004: break;
1005: }
1006: if (!valid_data)
1.14 markus 1007: fatal("%s: bad signature data blob", __func__);
1.1 provos 1008:
1009: verified = key_verify(key, signature, signaturelen, data, datalen);
1010: debug3("%s: key %p signature %s",
1.14 markus 1011: __func__, key, verified ? "verified" : "unverified");
1.1 provos 1012:
1013: key_free(key);
1014: xfree(blob);
1015: xfree(signature);
1016: xfree(data);
1017:
1.17 stevesk 1018: auth_method = key_blobtype == MM_USERKEY ? "publickey" : "hostbased";
1019:
1.1 provos 1020: monitor_reset_key_state();
1.3 markus 1021:
1.1 provos 1022: buffer_clear(m);
1023: buffer_put_int(m, verified);
1.59 avsm 1024: mm_request_send(sock, MONITOR_ANS_KEYVERIFY, m);
1.1 provos 1025:
1026: return (verified);
1027: }
1028:
1.2 markus 1029: static void
1.1 provos 1030: mm_record_login(Session *s, struct passwd *pw)
1031: {
1032: socklen_t fromlen;
1033: struct sockaddr_storage from;
1034:
1035: /*
1036: * Get IP address of client. If the connection is not a socket, let
1037: * the address be 0.0.0.0.
1038: */
1039: memset(&from, 0, sizeof(from));
1.24 stevesk 1040: fromlen = sizeof(from);
1.1 provos 1041: if (packet_connection_is_on_socket()) {
1042: if (getpeername(packet_get_connection_in(),
1.74 deraadt 1043: (struct sockaddr *)&from, &fromlen) < 0) {
1.1 provos 1044: debug("getpeername: %.100s", strerror(errno));
1.50 markus 1045: cleanup_exit(255);
1.1 provos 1046: }
1047: }
1048: /* Record that there was a login on that tty from the remote host. */
1049: record_login(s->pid, s->tty, pw->pw_name, pw->pw_uid,
1.42 markus 1050: get_remote_name_or_ip(utmp_len, options.use_dns),
1.24 stevesk 1051: (struct sockaddr *)&from, fromlen);
1.1 provos 1052: }
1053:
1054: static void
1055: mm_session_close(Session *s)
1056: {
1.41 djm 1057: debug3("%s: session %d pid %ld", __func__, s->self, (long)s->pid);
1.1 provos 1058: if (s->ttyfd != -1) {
1.14 markus 1059: debug3("%s: tty %s ptyfd %d", __func__, s->tty, s->ptyfd);
1.1 provos 1060: session_pty_cleanup2(s);
1061: }
1062: s->used = 0;
1063: }
1064:
1065: int
1.59 avsm 1066: mm_answer_pty(int sock, Buffer *m)
1.1 provos 1067: {
1.11 mouring 1068: extern struct monitor *pmonitor;
1.1 provos 1069: Session *s;
1070: int res, fd0;
1071:
1.14 markus 1072: debug3("%s entering", __func__);
1.1 provos 1073:
1074: buffer_clear(m);
1075: s = session_new();
1076: if (s == NULL)
1077: goto error;
1078: s->authctxt = authctxt;
1079: s->pw = authctxt->pw;
1.11 mouring 1080: s->pid = pmonitor->m_pid;
1.1 provos 1081: res = pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty));
1082: if (res == 0)
1083: goto error;
1084: pty_setowner(authctxt->pw, s->tty);
1085:
1086: buffer_put_int(m, 1);
1087: buffer_put_cstring(m, s->tty);
1088:
1089: /* We need to trick ttyslot */
1090: if (dup2(s->ttyfd, 0) == -1)
1.14 markus 1091: fatal("%s: dup2", __func__);
1.1 provos 1092:
1093: mm_record_login(s, authctxt->pw);
1094:
1095: /* Now we can close the file descriptor again */
1096: close(0);
1.61 dtucker 1097:
1098: /* send messages generated by record_login */
1099: buffer_put_string(m, buffer_ptr(&loginmsg), buffer_len(&loginmsg));
1100: buffer_clear(&loginmsg);
1101:
1102: mm_request_send(sock, MONITOR_ANS_PTY, m);
1103:
1104: mm_send_fd(sock, s->ptyfd);
1105: mm_send_fd(sock, s->ttyfd);
1.1 provos 1106:
1107: /* make sure nothing uses fd 0 */
1108: if ((fd0 = open(_PATH_DEVNULL, O_RDONLY)) < 0)
1.14 markus 1109: fatal("%s: open(/dev/null): %s", __func__, strerror(errno));
1.1 provos 1110: if (fd0 != 0)
1.14 markus 1111: error("%s: fd0 %d != 0", __func__, fd0);
1.1 provos 1112:
1113: /* slave is not needed */
1114: close(s->ttyfd);
1115: s->ttyfd = s->ptyfd;
1116: /* no need to dup() because nobody closes ptyfd */
1117: s->ptymaster = s->ptyfd;
1118:
1.14 markus 1119: debug3("%s: tty %s ptyfd %d", __func__, s->tty, s->ttyfd);
1.1 provos 1120:
1121: return (0);
1122:
1123: error:
1124: if (s != NULL)
1125: mm_session_close(s);
1126: buffer_put_int(m, 0);
1.59 avsm 1127: mm_request_send(sock, MONITOR_ANS_PTY, m);
1.1 provos 1128: return (0);
1129: }
1130:
1131: int
1.59 avsm 1132: mm_answer_pty_cleanup(int sock, Buffer *m)
1.1 provos 1133: {
1134: Session *s;
1135: char *tty;
1136:
1.14 markus 1137: debug3("%s entering", __func__);
1.1 provos 1138:
1139: tty = buffer_get_string(m, NULL);
1140: if ((s = session_by_tty(tty)) != NULL)
1141: mm_session_close(s);
1142: buffer_clear(m);
1143: xfree(tty);
1144: return (0);
1145: }
1146:
1147: int
1.59 avsm 1148: mm_answer_sesskey(int sock, Buffer *m)
1.1 provos 1149: {
1150: BIGNUM *p;
1151: int rsafail;
1152:
1153: /* Turn off permissions */
1.62 dtucker 1154: monitor_permit(mon_dispatch, MONITOR_REQ_SESSKEY, 0);
1.1 provos 1155:
1156: if ((p = BN_new()) == NULL)
1.14 markus 1157: fatal("%s: BN_new", __func__);
1.1 provos 1158:
1159: buffer_get_bignum2(m, p);
1160:
1161: rsafail = ssh1_session_key(p);
1162:
1163: buffer_clear(m);
1164: buffer_put_int(m, rsafail);
1165: buffer_put_bignum2(m, p);
1166:
1167: BN_clear_free(p);
1168:
1.59 avsm 1169: mm_request_send(sock, MONITOR_ANS_SESSKEY, m);
1.1 provos 1170:
1171: /* Turn on permissions for sessid passing */
1172: monitor_permit(mon_dispatch, MONITOR_REQ_SESSID, 1);
1173:
1174: return (0);
1175: }
1176:
1177: int
1.59 avsm 1178: mm_answer_sessid(int sock, Buffer *m)
1.1 provos 1179: {
1180: int i;
1181:
1.14 markus 1182: debug3("%s entering", __func__);
1.1 provos 1183:
1184: if (buffer_len(m) != 16)
1.14 markus 1185: fatal("%s: bad ssh1 session id", __func__);
1.1 provos 1186: for (i = 0; i < 16; i++)
1187: session_id[i] = buffer_get_char(m);
1188:
1189: /* Turn on permissions for getpwnam */
1190: monitor_permit(mon_dispatch, MONITOR_REQ_PWNAM, 1);
1191:
1192: return (0);
1193: }
1194:
1195: int
1.59 avsm 1196: mm_answer_rsa_keyallowed(int sock, Buffer *m)
1.1 provos 1197: {
1198: BIGNUM *client_n;
1199: Key *key = NULL;
1.3 markus 1200: u_char *blob = NULL;
1201: u_int blen = 0;
1.1 provos 1202: int allowed = 0;
1203:
1.14 markus 1204: debug3("%s entering", __func__);
1.1 provos 1205:
1.77 dtucker 1206: auth_method = "rsa";
1.12 markus 1207: if (options.rsa_authentication && authctxt->valid) {
1.1 provos 1208: if ((client_n = BN_new()) == NULL)
1.14 markus 1209: fatal("%s: BN_new", __func__);
1.1 provos 1210: buffer_get_bignum2(m, client_n);
1211: allowed = auth_rsa_key_allowed(authctxt->pw, client_n, &key);
1212: BN_clear_free(client_n);
1213: }
1214: buffer_clear(m);
1215: buffer_put_int(m, allowed);
1.32 markus 1216: buffer_put_int(m, forced_command != NULL);
1.1 provos 1217:
1218: /* clear temporarily storage (used by generate challenge) */
1219: monitor_reset_key_state();
1220:
1221: if (allowed && key != NULL) {
1222: key->type = KEY_RSA; /* cheat for key_to_blob */
1223: if (key_to_blob(key, &blob, &blen) == 0)
1.14 markus 1224: fatal("%s: key_to_blob failed", __func__);
1.1 provos 1225: buffer_put_string(m, blob, blen);
1226:
1227: /* Save temporarily for comparison in verify */
1228: key_blob = blob;
1229: key_bloblen = blen;
1230: key_blobtype = MM_RSAUSERKEY;
1.33 markus 1231: }
1232: if (key != NULL)
1.1 provos 1233: key_free(key);
1234:
1235: mm_append_debug(m);
1236:
1.59 avsm 1237: mm_request_send(sock, MONITOR_ANS_RSAKEYALLOWED, m);
1.1 provos 1238:
1239: monitor_permit(mon_dispatch, MONITOR_REQ_RSACHALLENGE, allowed);
1240: monitor_permit(mon_dispatch, MONITOR_REQ_RSARESPONSE, 0);
1241: return (0);
1242: }
1243:
1244: int
1.59 avsm 1245: mm_answer_rsa_challenge(int sock, Buffer *m)
1.1 provos 1246: {
1247: Key *key = NULL;
1.3 markus 1248: u_char *blob;
1249: u_int blen;
1.1 provos 1250:
1.14 markus 1251: debug3("%s entering", __func__);
1.1 provos 1252:
1253: if (!authctxt->valid)
1.14 markus 1254: fatal("%s: authctxt not valid", __func__);
1.1 provos 1255: blob = buffer_get_string(m, &blen);
1256: if (!monitor_allowed_key(blob, blen))
1.14 markus 1257: fatal("%s: bad key, not previously allowed", __func__);
1.1 provos 1258: if (key_blobtype != MM_RSAUSERKEY && key_blobtype != MM_RSAHOSTKEY)
1.14 markus 1259: fatal("%s: key type mismatch", __func__);
1.1 provos 1260: if ((key = key_from_blob(blob, blen)) == NULL)
1.14 markus 1261: fatal("%s: received bad key", __func__);
1.1 provos 1262:
1263: if (ssh1_challenge)
1264: BN_clear_free(ssh1_challenge);
1265: ssh1_challenge = auth_rsa_generate_challenge(key);
1266:
1267: buffer_clear(m);
1268: buffer_put_bignum2(m, ssh1_challenge);
1269:
1.14 markus 1270: debug3("%s sending reply", __func__);
1.59 avsm 1271: mm_request_send(sock, MONITOR_ANS_RSACHALLENGE, m);
1.1 provos 1272:
1273: monitor_permit(mon_dispatch, MONITOR_REQ_RSARESPONSE, 1);
1.33 markus 1274:
1275: xfree(blob);
1276: key_free(key);
1.1 provos 1277: return (0);
1278: }
1279:
1280: int
1.59 avsm 1281: mm_answer_rsa_response(int sock, Buffer *m)
1.1 provos 1282: {
1283: Key *key = NULL;
1.3 markus 1284: u_char *blob, *response;
1285: u_int blen, len;
1286: int success;
1.1 provos 1287:
1.14 markus 1288: debug3("%s entering", __func__);
1.1 provos 1289:
1290: if (!authctxt->valid)
1.14 markus 1291: fatal("%s: authctxt not valid", __func__);
1.1 provos 1292: if (ssh1_challenge == NULL)
1.14 markus 1293: fatal("%s: no ssh1_challenge", __func__);
1.1 provos 1294:
1295: blob = buffer_get_string(m, &blen);
1296: if (!monitor_allowed_key(blob, blen))
1.14 markus 1297: fatal("%s: bad key, not previously allowed", __func__);
1.1 provos 1298: if (key_blobtype != MM_RSAUSERKEY && key_blobtype != MM_RSAHOSTKEY)
1.14 markus 1299: fatal("%s: key type mismatch: %d", __func__, key_blobtype);
1.1 provos 1300: if ((key = key_from_blob(blob, blen)) == NULL)
1.14 markus 1301: fatal("%s: received bad key", __func__);
1.1 provos 1302: response = buffer_get_string(m, &len);
1303: if (len != 16)
1.14 markus 1304: fatal("%s: received bad response to challenge", __func__);
1.1 provos 1305: success = auth_rsa_verify_response(key, ssh1_challenge, response);
1306:
1.33 markus 1307: xfree(blob);
1.1 provos 1308: key_free(key);
1309: xfree(response);
1310:
1311: auth_method = key_blobtype == MM_RSAUSERKEY ? "rsa" : "rhosts-rsa";
1312:
1313: /* reset state */
1314: BN_clear_free(ssh1_challenge);
1315: ssh1_challenge = NULL;
1316: monitor_reset_key_state();
1317:
1318: buffer_clear(m);
1319: buffer_put_int(m, success);
1.59 avsm 1320: mm_request_send(sock, MONITOR_ANS_RSARESPONSE, m);
1.1 provos 1321:
1322: return (success);
1323: }
1324:
1325: int
1.59 avsm 1326: mm_answer_term(int sock, Buffer *req)
1.1 provos 1327: {
1.11 mouring 1328: extern struct monitor *pmonitor;
1.1 provos 1329: int res, status;
1330:
1.14 markus 1331: debug3("%s: tearing down sessions", __func__);
1.1 provos 1332:
1333: /* The child is terminating */
1334: session_destroy_all(&mm_session_close);
1335:
1.11 mouring 1336: while (waitpid(pmonitor->m_pid, &status, 0) == -1)
1.9 markus 1337: if (errno != EINTR)
1338: exit(1);
1.1 provos 1339:
1340: res = WIFEXITED(status) ? WEXITSTATUS(status) : 1;
1341:
1342: /* Terminate process */
1.57 deraadt 1343: exit(res);
1.1 provos 1344: }
1345:
1346: void
1.11 mouring 1347: monitor_apply_keystate(struct monitor *pmonitor)
1.1 provos 1348: {
1349: if (compat20) {
1350: set_newkeys(MODE_IN);
1351: set_newkeys(MODE_OUT);
1352: } else {
1353: packet_set_protocol_flags(child_state.ssh1protoflags);
1.15 markus 1354: packet_set_encryption_key(child_state.ssh1key,
1355: child_state.ssh1keylen, child_state.ssh1cipher);
1356: xfree(child_state.ssh1key);
1.1 provos 1357: }
1358:
1.15 markus 1359: /* for rc4 and other stateful ciphers */
1.1 provos 1360: packet_set_keycontext(MODE_OUT, child_state.keyout);
1361: xfree(child_state.keyout);
1362: packet_set_keycontext(MODE_IN, child_state.keyin);
1363: xfree(child_state.keyin);
1364:
1365: if (!compat20) {
1366: packet_set_iv(MODE_OUT, child_state.ivout);
1367: xfree(child_state.ivout);
1368: packet_set_iv(MODE_IN, child_state.ivin);
1369: xfree(child_state.ivin);
1370: }
1371:
1372: memcpy(&incoming_stream, &child_state.incoming,
1373: sizeof(incoming_stream));
1374: memcpy(&outgoing_stream, &child_state.outgoing,
1375: sizeof(outgoing_stream));
1.3 markus 1376:
1.1 provos 1377: /* Update with new address */
1.16 djm 1378: if (options.compression)
1379: mm_init_compression(pmonitor->m_zlib);
1.1 provos 1380:
1381: /* Network I/O buffers */
1382: /* XXX inefficient for large buffers, need: buffer_init_from_string */
1383: buffer_clear(&input);
1384: buffer_append(&input, child_state.input, child_state.ilen);
1385: memset(child_state.input, 0, child_state.ilen);
1386: xfree(child_state.input);
1387:
1388: buffer_clear(&output);
1389: buffer_append(&output, child_state.output, child_state.olen);
1390: memset(child_state.output, 0, child_state.olen);
1391: xfree(child_state.output);
1392: }
1393:
1.2 markus 1394: static Kex *
1.1 provos 1395: mm_get_kex(Buffer *m)
1396: {
1397: Kex *kex;
1398: void *blob;
1399: u_int bloblen;
1400:
1.75 djm 1401: kex = xcalloc(1, sizeof(*kex));
1.1 provos 1402: kex->session_id = buffer_get_string(m, &kex->session_id_len);
1.13 markus 1403: if ((session_id2 == NULL) ||
1404: (kex->session_id_len != session_id2_len) ||
1405: (memcmp(kex->session_id, session_id2, session_id2_len) != 0))
1406: fatal("mm_get_get: internal error: bad session id");
1.1 provos 1407: kex->we_need = buffer_get_int(m);
1.34 markus 1408: kex->kex[KEX_DH_GRP1_SHA1] = kexdh_server;
1.58 djm 1409: kex->kex[KEX_DH_GRP14_SHA1] = kexdh_server;
1.34 markus 1410: kex->kex[KEX_DH_GEX_SHA1] = kexgex_server;
1.69 djm 1411: kex->kex[KEX_DH_GEX_SHA256] = kexgex_server;
1.1 provos 1412: kex->server = 1;
1413: kex->hostkey_type = buffer_get_int(m);
1414: kex->kex_type = buffer_get_int(m);
1415: blob = buffer_get_string(m, &bloblen);
1416: buffer_init(&kex->my);
1417: buffer_append(&kex->my, blob, bloblen);
1418: xfree(blob);
1419: blob = buffer_get_string(m, &bloblen);
1420: buffer_init(&kex->peer);
1421: buffer_append(&kex->peer, blob, bloblen);
1422: xfree(blob);
1423: kex->done = 1;
1424: kex->flags = buffer_get_int(m);
1425: kex->client_version_string = buffer_get_string(m, NULL);
1426: kex->server_version_string = buffer_get_string(m, NULL);
1427: kex->load_host_key=&get_hostkey_by_type;
1428: kex->host_key_index=&get_hostkey_index;
1429:
1430: return (kex);
1431: }
1432:
1433: /* This function requries careful sanity checking */
1434:
1435: void
1.11 mouring 1436: mm_get_keystate(struct monitor *pmonitor)
1.1 provos 1437: {
1438: Buffer m;
1439: u_char *blob, *p;
1440: u_int bloblen, plen;
1.37 markus 1441: u_int32_t seqnr, packets;
1442: u_int64_t blocks;
1.1 provos 1443:
1.14 markus 1444: debug3("%s: Waiting for new keys", __func__);
1.1 provos 1445:
1446: buffer_init(&m);
1.11 mouring 1447: mm_request_receive_expect(pmonitor->m_sendfd, MONITOR_REQ_KEYEXPORT, &m);
1.1 provos 1448: if (!compat20) {
1449: child_state.ssh1protoflags = buffer_get_int(&m);
1450: child_state.ssh1cipher = buffer_get_int(&m);
1.15 markus 1451: child_state.ssh1key = buffer_get_string(&m,
1452: &child_state.ssh1keylen);
1.1 provos 1453: child_state.ivout = buffer_get_string(&m,
1454: &child_state.ivoutlen);
1455: child_state.ivin = buffer_get_string(&m, &child_state.ivinlen);
1456: goto skip;
1457: } else {
1458: /* Get the Kex for rekeying */
1.11 mouring 1459: *pmonitor->m_pkex = mm_get_kex(&m);
1.1 provos 1460: }
1461:
1462: blob = buffer_get_string(&m, &bloblen);
1463: current_keys[MODE_OUT] = mm_newkeys_from_blob(blob, bloblen);
1464: xfree(blob);
1465:
1.14 markus 1466: debug3("%s: Waiting for second key", __func__);
1.1 provos 1467: blob = buffer_get_string(&m, &bloblen);
1468: current_keys[MODE_IN] = mm_newkeys_from_blob(blob, bloblen);
1469: xfree(blob);
1.3 markus 1470:
1.1 provos 1471: /* Now get sequence numbers for the packets */
1.37 markus 1472: seqnr = buffer_get_int(&m);
1473: blocks = buffer_get_int64(&m);
1474: packets = buffer_get_int(&m);
1475: packet_set_state(MODE_OUT, seqnr, blocks, packets);
1476: seqnr = buffer_get_int(&m);
1477: blocks = buffer_get_int64(&m);
1478: packets = buffer_get_int(&m);
1479: packet_set_state(MODE_IN, seqnr, blocks, packets);
1.1 provos 1480:
1481: skip:
1482: /* Get the key context */
1483: child_state.keyout = buffer_get_string(&m, &child_state.keyoutlen);
1484: child_state.keyin = buffer_get_string(&m, &child_state.keyinlen);
1485:
1.14 markus 1486: debug3("%s: Getting compression state", __func__);
1.1 provos 1487: /* Get compression state */
1488: p = buffer_get_string(&m, &plen);
1489: if (plen != sizeof(child_state.outgoing))
1.14 markus 1490: fatal("%s: bad request size", __func__);
1.1 provos 1491: memcpy(&child_state.outgoing, p, sizeof(child_state.outgoing));
1492: xfree(p);
1493:
1494: p = buffer_get_string(&m, &plen);
1495: if (plen != sizeof(child_state.incoming))
1.14 markus 1496: fatal("%s: bad request size", __func__);
1.1 provos 1497: memcpy(&child_state.incoming, p, sizeof(child_state.incoming));
1498: xfree(p);
1499:
1500: /* Network I/O buffers */
1.14 markus 1501: debug3("%s: Getting Network I/O buffers", __func__);
1.1 provos 1502: child_state.input = buffer_get_string(&m, &child_state.ilen);
1503: child_state.output = buffer_get_string(&m, &child_state.olen);
1504:
1505: buffer_free(&m);
1506: }
1507:
1508:
1509: /* Allocation functions for zlib */
1510: void *
1511: mm_zalloc(struct mm_master *mm, u_int ncount, u_int size)
1512: {
1.30 markus 1513: size_t len = (size_t) size * ncount;
1.1 provos 1514: void *address;
1515:
1.23 millert 1516: if (len == 0 || ncount > SIZE_T_MAX / size)
1.18 deraadt 1517: fatal("%s: mm_zalloc(%u, %u)", __func__, ncount, size);
1518:
1519: address = mm_malloc(mm, len);
1.1 provos 1520:
1521: return (address);
1522: }
1523:
1524: void
1525: mm_zfree(struct mm_master *mm, void *address)
1526: {
1527: mm_free(mm, address);
1528: }
1529:
1530: void
1531: mm_init_compression(struct mm_master *mm)
1532: {
1533: outgoing_stream.zalloc = (alloc_func)mm_zalloc;
1534: outgoing_stream.zfree = (free_func)mm_zfree;
1535: outgoing_stream.opaque = mm;
1536:
1537: incoming_stream.zalloc = (alloc_func)mm_zalloc;
1538: incoming_stream.zfree = (free_func)mm_zfree;
1539: incoming_stream.opaque = mm;
1540: }
1541:
1542: /* XXX */
1543:
1544: #define FD_CLOSEONEXEC(x) do { \
1545: if (fcntl(x, F_SETFD, 1) == -1) \
1546: fatal("fcntl(%d, F_SETFD)", x); \
1547: } while (0)
1548:
1.2 markus 1549: static void
1.1 provos 1550: monitor_socketpair(int *pair)
1.3 markus 1551: {
1.1 provos 1552: if (socketpair(AF_UNIX, SOCK_STREAM, 0, pair) == -1)
1.14 markus 1553: fatal("%s: socketpair", __func__);
1.1 provos 1554: FD_CLOSEONEXEC(pair[0]);
1555: FD_CLOSEONEXEC(pair[1]);
1556: }
1557:
1558: #define MM_MEMSIZE 65536
1559:
1560: struct monitor *
1561: monitor_init(void)
1562: {
1563: struct monitor *mon;
1564: int pair[2];
1565:
1.75 djm 1566: mon = xcalloc(1, sizeof(*mon));
1.1 provos 1567:
1568: monitor_socketpair(pair);
1569:
1570: mon->m_recvfd = pair[0];
1571: mon->m_sendfd = pair[1];
1572:
1573: /* Used to share zlib space across processes */
1.16 djm 1574: if (options.compression) {
1575: mon->m_zback = mm_create(NULL, MM_MEMSIZE);
1576: mon->m_zlib = mm_create(mon->m_zback, 20 * MM_MEMSIZE);
1.1 provos 1577:
1.16 djm 1578: /* Compression needs to share state across borders */
1579: mm_init_compression(mon->m_zlib);
1580: }
1.1 provos 1581:
1582: return mon;
1583: }
1584:
1585: void
1586: monitor_reinit(struct monitor *mon)
1587: {
1588: int pair[2];
1589:
1590: monitor_socketpair(pair);
1591:
1592: mon->m_recvfd = pair[0];
1593: mon->m_sendfd = pair[1];
1594: }
1.46 markus 1595:
1596: #ifdef GSSAPI
1597: int
1.59 avsm 1598: mm_answer_gss_setup_ctx(int sock, Buffer *m)
1.46 markus 1599: {
1.59 avsm 1600: gss_OID_desc goid;
1.46 markus 1601: OM_uint32 major;
1602: u_int len;
1603:
1.59 avsm 1604: goid.elements = buffer_get_string(m, &len);
1605: goid.length = len;
1.46 markus 1606:
1.59 avsm 1607: major = ssh_gssapi_server_ctx(&gsscontext, &goid);
1.46 markus 1608:
1.59 avsm 1609: xfree(goid.elements);
1.46 markus 1610:
1611: buffer_clear(m);
1612: buffer_put_int(m, major);
1613:
1.64 stevesk 1614: mm_request_send(sock, MONITOR_ANS_GSSSETUP, m);
1.46 markus 1615:
1616: /* Now we have a context, enable the step */
1617: monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 1);
1618:
1619: return (0);
1620: }
1621:
1622: int
1.59 avsm 1623: mm_answer_gss_accept_ctx(int sock, Buffer *m)
1.46 markus 1624: {
1625: gss_buffer_desc in;
1626: gss_buffer_desc out = GSS_C_EMPTY_BUFFER;
1.64 stevesk 1627: OM_uint32 major, minor;
1.46 markus 1628: OM_uint32 flags = 0; /* GSI needs this */
1.47 deraadt 1629: u_int len;
1.46 markus 1630:
1.47 deraadt 1631: in.value = buffer_get_string(m, &len);
1632: in.length = len;
1.46 markus 1633: major = ssh_gssapi_accept_ctx(gsscontext, &in, &out, &flags);
1634: xfree(in.value);
1635:
1636: buffer_clear(m);
1637: buffer_put_int(m, major);
1638: buffer_put_string(m, out.value, out.length);
1639: buffer_put_int(m, flags);
1.59 avsm 1640: mm_request_send(sock, MONITOR_ANS_GSSSTEP, m);
1.46 markus 1641:
1642: gss_release_buffer(&minor, &out);
1643:
1.64 stevesk 1644: if (major == GSS_S_COMPLETE) {
1.46 markus 1645: monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 0);
1646: monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
1.52 markus 1647: monitor_permit(mon_dispatch, MONITOR_REQ_GSSCHECKMIC, 1);
1.46 markus 1648: }
1649: return (0);
1650: }
1651:
1652: int
1.59 avsm 1653: mm_answer_gss_checkmic(int sock, Buffer *m)
1.52 markus 1654: {
1655: gss_buffer_desc gssbuf, mic;
1656: OM_uint32 ret;
1657: u_int len;
1.54 djm 1658:
1.52 markus 1659: gssbuf.value = buffer_get_string(m, &len);
1660: gssbuf.length = len;
1661: mic.value = buffer_get_string(m, &len);
1662: mic.length = len;
1.54 djm 1663:
1.52 markus 1664: ret = ssh_gssapi_checkmic(gsscontext, &gssbuf, &mic);
1.54 djm 1665:
1.52 markus 1666: xfree(gssbuf.value);
1667: xfree(mic.value);
1.54 djm 1668:
1.52 markus 1669: buffer_clear(m);
1670: buffer_put_int(m, ret);
1.54 djm 1671:
1.59 avsm 1672: mm_request_send(sock, MONITOR_ANS_GSSCHECKMIC, m);
1.54 djm 1673:
1.52 markus 1674: if (!GSS_ERROR(ret))
1675: monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
1.54 djm 1676:
1.52 markus 1677: return (0);
1678: }
1679:
1680: int
1.59 avsm 1681: mm_answer_gss_userok(int sock, Buffer *m)
1.46 markus 1682: {
1683: int authenticated;
1684:
1685: authenticated = authctxt->valid && ssh_gssapi_userok(authctxt->user);
1686:
1687: buffer_clear(m);
1688: buffer_put_int(m, authenticated);
1689:
1690: debug3("%s: sending result %d", __func__, authenticated);
1.59 avsm 1691: mm_request_send(sock, MONITOR_ANS_GSSUSEROK, m);
1.46 markus 1692:
1.64 stevesk 1693: auth_method = "gssapi-with-mic";
1.46 markus 1694:
1695: /* Monitor loop will terminate if authenticated */
1696: return (authenticated);
1697: }
1698: #endif /* GSSAPI */
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