Annotation of src/usr.bin/ssh/monitor.c, Revision 1.90
1.90 ! dtucker 1: /* $OpenBSD: monitor.c,v 1.89 2006/11/07 10:31:31 markus 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"
1.88 miod 57: #include <zlib.h>
1.1 provos 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";
1.89 markus 295: authenticated = (monitor_read(pmonitor, mon_dispatch, &ent) == 1);
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);
1.90 ! dtucker 573: buffer_put_string(m, &options, sizeof(options));
! 574: if (options.banner != NULL)
! 575: buffer_put_cstring(m, options.banner);
1.1 provos 576:
577: out:
1.14 markus 578: debug3("%s: sending MONITOR_ANS_PWNAM: %d", __func__, allowed);
1.59 avsm 579: mm_request_send(sock, MONITOR_ANS_PWNAM, m);
1.1 provos 580:
581: /* For SSHv1 allow authentication now */
582: if (!compat20)
583: monitor_permit_authentications(1);
1.10 djm 584: else {
1.1 provos 585: /* Allow service/style information on the auth context */
586: monitor_permit(mon_dispatch, MONITOR_REQ_AUTHSERV, 1);
1.10 djm 587: monitor_permit(mon_dispatch, MONITOR_REQ_AUTH2_READ_BANNER, 1);
588: }
589:
590:
591: return (0);
592: }
593:
1.59 avsm 594: int mm_answer_auth2_read_banner(int sock, Buffer *m)
1.10 djm 595: {
596: char *banner;
597:
598: buffer_clear(m);
599: banner = auth2_read_banner();
600: buffer_put_cstring(m, banner != NULL ? banner : "");
1.59 avsm 601: mm_request_send(sock, MONITOR_ANS_AUTH2_READ_BANNER, m);
1.1 provos 602:
1.10 djm 603: if (banner != NULL)
1.21 deraadt 604: xfree(banner);
1.1 provos 605:
606: return (0);
607: }
608:
609: int
1.59 avsm 610: mm_answer_authserv(int sock, Buffer *m)
1.1 provos 611: {
612: monitor_permit_authentications(1);
613:
614: authctxt->service = buffer_get_string(m, NULL);
615: authctxt->style = buffer_get_string(m, NULL);
1.6 stevesk 616: debug3("%s: service=%s, style=%s",
1.14 markus 617: __func__, authctxt->service, authctxt->style);
1.6 stevesk 618:
1.1 provos 619: if (strlen(authctxt->style) == 0) {
620: xfree(authctxt->style);
621: authctxt->style = NULL;
622: }
623:
624: return (0);
625: }
626:
627: int
1.59 avsm 628: mm_answer_authpassword(int sock, Buffer *m)
1.1 provos 629: {
630: static int call_count;
631: char *passwd;
1.22 stevesk 632: int authenticated;
633: u_int plen;
1.1 provos 634:
635: passwd = buffer_get_string(m, &plen);
636: /* Only authenticate if the context is valid */
1.12 markus 637: authenticated = options.password_authentication &&
1.48 markus 638: auth_password(authctxt, passwd);
1.1 provos 639: memset(passwd, 0, strlen(passwd));
640: xfree(passwd);
641:
642: buffer_clear(m);
643: buffer_put_int(m, authenticated);
644:
1.14 markus 645: debug3("%s: sending result %d", __func__, authenticated);
1.59 avsm 646: mm_request_send(sock, MONITOR_ANS_AUTHPASSWORD, m);
1.1 provos 647:
648: call_count++;
649: if (plen == 0 && call_count == 1)
650: auth_method = "none";
651: else
652: auth_method = "password";
653:
654: /* Causes monitor loop to terminate if authenticated */
655: return (authenticated);
656: }
657:
658: #ifdef BSD_AUTH
659: int
1.59 avsm 660: mm_answer_bsdauthquery(int sock, Buffer *m)
1.1 provos 661: {
662: char *name, *infotxt;
663: u_int numprompts;
664: u_int *echo_on;
665: char **prompts;
1.31 markus 666: u_int success;
1.1 provos 667:
1.31 markus 668: success = bsdauth_query(authctxt, &name, &infotxt, &numprompts,
669: &prompts, &echo_on) < 0 ? 0 : 1;
1.1 provos 670:
671: buffer_clear(m);
1.31 markus 672: buffer_put_int(m, success);
673: if (success)
1.1 provos 674: buffer_put_cstring(m, prompts[0]);
675:
1.31 markus 676: debug3("%s: sending challenge success: %u", __func__, success);
1.59 avsm 677: mm_request_send(sock, MONITOR_ANS_BSDAUTHQUERY, m);
1.1 provos 678:
1.31 markus 679: if (success) {
1.1 provos 680: xfree(name);
681: xfree(infotxt);
682: xfree(prompts);
683: xfree(echo_on);
684: }
685:
686: return (0);
687: }
688:
689: int
1.59 avsm 690: mm_answer_bsdauthrespond(int sock, Buffer *m)
1.1 provos 691: {
692: char *response;
693: int authok;
694:
695: if (authctxt->as == 0)
1.14 markus 696: fatal("%s: no bsd auth session", __func__);
1.1 provos 697:
698: response = buffer_get_string(m, NULL);
1.12 markus 699: authok = options.challenge_response_authentication &&
700: auth_userresponse(authctxt->as, response, 0);
1.1 provos 701: authctxt->as = NULL;
1.14 markus 702: debug3("%s: <%s> = <%d>", __func__, response, authok);
1.1 provos 703: xfree(response);
704:
705: buffer_clear(m);
706: buffer_put_int(m, authok);
707:
1.14 markus 708: debug3("%s: sending authenticated: %d", __func__, authok);
1.59 avsm 709: mm_request_send(sock, MONITOR_ANS_BSDAUTHRESPOND, m);
1.1 provos 710:
711: auth_method = "bsdauth";
712:
713: return (authok != 0);
714: }
715: #endif
716:
717: #ifdef SKEY
718: int
1.59 avsm 719: mm_answer_skeyquery(int sock, Buffer *m)
1.1 provos 720: {
721: struct skey skey;
722: char challenge[1024];
1.31 markus 723: u_int success;
1.1 provos 724:
1.31 markus 725: success = skeychallenge(&skey, authctxt->user, challenge) < 0 ? 0 : 1;
1.1 provos 726:
727: buffer_clear(m);
1.31 markus 728: buffer_put_int(m, success);
729: if (success)
1.1 provos 730: buffer_put_cstring(m, challenge);
731:
1.31 markus 732: debug3("%s: sending challenge success: %u", __func__, success);
1.59 avsm 733: mm_request_send(sock, MONITOR_ANS_SKEYQUERY, m);
1.1 provos 734:
735: return (0);
736: }
737:
738: int
1.59 avsm 739: mm_answer_skeyrespond(int sock, Buffer *m)
1.1 provos 740: {
741: char *response;
742: int authok;
743:
744: response = buffer_get_string(m, NULL);
745:
1.12 markus 746: authok = (options.challenge_response_authentication &&
747: authctxt->valid &&
1.1 provos 748: skey_haskey(authctxt->pw->pw_name) == 0 &&
749: skey_passcheck(authctxt->pw->pw_name, response) != -1);
750:
751: xfree(response);
752:
753: buffer_clear(m);
754: buffer_put_int(m, authok);
755:
1.14 markus 756: debug3("%s: sending authenticated: %d", __func__, authok);
1.59 avsm 757: mm_request_send(sock, MONITOR_ANS_SKEYRESPOND, m);
1.1 provos 758:
759: auth_method = "skey";
760:
761: return (authok != 0);
762: }
763: #endif
764:
1.2 markus 765: static void
1.1 provos 766: mm_append_debug(Buffer *m)
767: {
768: if (auth_debug_init && buffer_len(&auth_debug)) {
1.14 markus 769: debug3("%s: Appending debug messages for child", __func__);
1.1 provos 770: buffer_append(m, buffer_ptr(&auth_debug),
771: buffer_len(&auth_debug));
772: buffer_clear(&auth_debug);
773: }
774: }
775:
776: int
1.59 avsm 777: mm_answer_keyallowed(int sock, Buffer *m)
1.1 provos 778: {
779: Key *key;
1.26 markus 780: char *cuser, *chost;
781: u_char *blob;
1.1 provos 782: u_int bloblen;
783: enum mm_keytype type = 0;
784: int allowed = 0;
785:
1.14 markus 786: debug3("%s entering", __func__);
1.3 markus 787:
1.1 provos 788: type = buffer_get_int(m);
789: cuser = buffer_get_string(m, NULL);
790: chost = buffer_get_string(m, NULL);
791: blob = buffer_get_string(m, &bloblen);
792:
793: key = key_from_blob(blob, bloblen);
794:
795: if ((compat20 && type == MM_RSAHOSTKEY) ||
796: (!compat20 && type != MM_RSAHOSTKEY))
1.14 markus 797: fatal("%s: key type and protocol mismatch", __func__);
1.1 provos 798:
1.14 markus 799: debug3("%s: key_from_blob: %p", __func__, key);
1.1 provos 800:
1.51 djm 801: if (key != NULL && authctxt->valid) {
1.63 deraadt 802: switch (type) {
1.1 provos 803: case MM_USERKEY:
1.12 markus 804: allowed = options.pubkey_authentication &&
805: user_key_allowed(authctxt->pw, key);
1.77 dtucker 806: auth_method = "publickey";
1.1 provos 807: break;
808: case MM_HOSTKEY:
1.12 markus 809: allowed = options.hostbased_authentication &&
810: hostbased_key_allowed(authctxt->pw,
1.1 provos 811: cuser, chost, key);
1.77 dtucker 812: auth_method = "hostbased";
1.1 provos 813: break;
814: case MM_RSAHOSTKEY:
815: key->type = KEY_RSA1; /* XXX */
1.12 markus 816: allowed = options.rhosts_rsa_authentication &&
817: auth_rhosts_rsa_key_allowed(authctxt->pw,
1.1 provos 818: cuser, chost, key);
1.77 dtucker 819: auth_method = "rsa";
1.1 provos 820: break;
821: default:
1.14 markus 822: fatal("%s: unknown key type %d", __func__, type);
1.1 provos 823: break;
824: }
1.33 markus 825: }
826: if (key != NULL)
1.1 provos 827: key_free(key);
828:
829: /* clear temporarily storage (used by verify) */
830: monitor_reset_key_state();
831:
832: if (allowed) {
833: /* Save temporarily for comparison in verify */
834: key_blob = blob;
835: key_bloblen = bloblen;
836: key_blobtype = type;
837: hostbased_cuser = cuser;
838: hostbased_chost = chost;
1.72 djm 839: } else {
1.77 dtucker 840: /* Log failed attempt */
841: auth_log(authctxt, 0, auth_method, compat20 ? " ssh2" : "");
1.72 djm 842: xfree(blob);
843: xfree(cuser);
844: xfree(chost);
1.1 provos 845: }
846:
847: debug3("%s: key %p is %s",
1.14 markus 848: __func__, key, allowed ? "allowed" : "disallowed");
1.1 provos 849:
850: buffer_clear(m);
851: buffer_put_int(m, allowed);
1.32 markus 852: buffer_put_int(m, forced_command != NULL);
1.1 provos 853:
854: mm_append_debug(m);
855:
1.59 avsm 856: mm_request_send(sock, MONITOR_ANS_KEYALLOWED, m);
1.1 provos 857:
858: if (type == MM_RSAHOSTKEY)
859: monitor_permit(mon_dispatch, MONITOR_REQ_RSACHALLENGE, allowed);
860:
861: return (0);
862: }
863:
864: static int
865: monitor_valid_userblob(u_char *data, u_int datalen)
866: {
867: Buffer b;
1.26 markus 868: char *p;
1.1 provos 869: u_int len;
870: int fail = 0;
871:
872: buffer_init(&b);
873: buffer_append(&b, data, datalen);
1.3 markus 874:
1.1 provos 875: if (datafellows & SSH_OLD_SESSIONID) {
1.13 markus 876: p = buffer_ptr(&b);
877: len = buffer_len(&b);
878: if ((session_id2 == NULL) ||
879: (len < session_id2_len) ||
880: (memcmp(p, session_id2, session_id2_len) != 0))
881: fail++;
1.1 provos 882: buffer_consume(&b, session_id2_len);
883: } else {
1.13 markus 884: p = buffer_get_string(&b, &len);
885: if ((session_id2 == NULL) ||
886: (len != session_id2_len) ||
887: (memcmp(p, session_id2, session_id2_len) != 0))
1.1 provos 888: fail++;
1.13 markus 889: xfree(p);
1.1 provos 890: }
891: if (buffer_get_char(&b) != SSH2_MSG_USERAUTH_REQUEST)
892: fail++;
893: p = buffer_get_string(&b, NULL);
894: if (strcmp(authctxt->user, p) != 0) {
1.38 itojun 895: logit("wrong user name passed to monitor: expected %s != %.100s",
1.1 provos 896: authctxt->user, p);
897: fail++;
898: }
899: xfree(p);
900: buffer_skip_string(&b);
901: if (datafellows & SSH_BUG_PKAUTH) {
902: if (!buffer_get_char(&b))
903: fail++;
904: } else {
905: p = buffer_get_string(&b, NULL);
906: if (strcmp("publickey", p) != 0)
907: fail++;
908: xfree(p);
909: if (!buffer_get_char(&b))
910: fail++;
911: buffer_skip_string(&b);
912: }
913: buffer_skip_string(&b);
914: if (buffer_len(&b) != 0)
915: fail++;
916: buffer_free(&b);
917: return (fail == 0);
918: }
919:
920: static int
1.26 markus 921: monitor_valid_hostbasedblob(u_char *data, u_int datalen, char *cuser,
922: char *chost)
1.1 provos 923: {
924: Buffer b;
1.26 markus 925: char *p;
1.1 provos 926: u_int len;
927: int fail = 0;
928:
929: buffer_init(&b);
930: buffer_append(&b, data, datalen);
1.3 markus 931:
1.13 markus 932: p = buffer_get_string(&b, &len);
933: if ((session_id2 == NULL) ||
934: (len != session_id2_len) ||
935: (memcmp(p, session_id2, session_id2_len) != 0))
1.1 provos 936: fail++;
1.13 markus 937: xfree(p);
938:
1.1 provos 939: if (buffer_get_char(&b) != SSH2_MSG_USERAUTH_REQUEST)
940: fail++;
941: p = buffer_get_string(&b, NULL);
942: if (strcmp(authctxt->user, p) != 0) {
1.38 itojun 943: logit("wrong user name passed to monitor: expected %s != %.100s",
1.1 provos 944: authctxt->user, p);
945: fail++;
946: }
947: xfree(p);
948: buffer_skip_string(&b); /* service */
949: p = buffer_get_string(&b, NULL);
950: if (strcmp(p, "hostbased") != 0)
951: fail++;
952: xfree(p);
953: buffer_skip_string(&b); /* pkalg */
954: buffer_skip_string(&b); /* pkblob */
955:
956: /* verify client host, strip trailing dot if necessary */
957: p = buffer_get_string(&b, NULL);
958: if (((len = strlen(p)) > 0) && p[len - 1] == '.')
959: p[len - 1] = '\0';
960: if (strcmp(p, chost) != 0)
961: fail++;
962: xfree(p);
963:
964: /* verify client user */
965: p = buffer_get_string(&b, NULL);
966: if (strcmp(p, cuser) != 0)
967: fail++;
968: xfree(p);
969:
970: if (buffer_len(&b) != 0)
971: fail++;
972: buffer_free(&b);
973: return (fail == 0);
974: }
975:
976: int
1.59 avsm 977: mm_answer_keyverify(int sock, Buffer *m)
1.1 provos 978: {
979: Key *key;
980: u_char *signature, *data, *blob;
981: u_int signaturelen, datalen, bloblen;
982: int verified = 0;
983: int valid_data = 0;
984:
985: blob = buffer_get_string(m, &bloblen);
986: signature = buffer_get_string(m, &signaturelen);
987: data = buffer_get_string(m, &datalen);
988:
989: if (hostbased_cuser == NULL || hostbased_chost == NULL ||
1.8 mouring 990: !monitor_allowed_key(blob, bloblen))
1.14 markus 991: fatal("%s: bad key, not previously allowed", __func__);
1.1 provos 992:
993: key = key_from_blob(blob, bloblen);
994: if (key == NULL)
1.14 markus 995: fatal("%s: bad public key blob", __func__);
1.1 provos 996:
997: switch (key_blobtype) {
998: case MM_USERKEY:
999: valid_data = monitor_valid_userblob(data, datalen);
1000: break;
1001: case MM_HOSTKEY:
1002: valid_data = monitor_valid_hostbasedblob(data, datalen,
1003: hostbased_cuser, hostbased_chost);
1004: break;
1005: default:
1006: valid_data = 0;
1007: break;
1008: }
1009: if (!valid_data)
1.14 markus 1010: fatal("%s: bad signature data blob", __func__);
1.1 provos 1011:
1012: verified = key_verify(key, signature, signaturelen, data, datalen);
1013: debug3("%s: key %p signature %s",
1.89 markus 1014: __func__, key, (verified == 1) ? "verified" : "unverified");
1.1 provos 1015:
1016: key_free(key);
1017: xfree(blob);
1018: xfree(signature);
1019: xfree(data);
1020:
1.17 stevesk 1021: auth_method = key_blobtype == MM_USERKEY ? "publickey" : "hostbased";
1022:
1.1 provos 1023: monitor_reset_key_state();
1.3 markus 1024:
1.1 provos 1025: buffer_clear(m);
1026: buffer_put_int(m, verified);
1.59 avsm 1027: mm_request_send(sock, MONITOR_ANS_KEYVERIFY, m);
1.1 provos 1028:
1.89 markus 1029: return (verified == 1);
1.1 provos 1030: }
1031:
1.2 markus 1032: static void
1.1 provos 1033: mm_record_login(Session *s, struct passwd *pw)
1034: {
1035: socklen_t fromlen;
1036: struct sockaddr_storage from;
1037:
1038: /*
1039: * Get IP address of client. If the connection is not a socket, let
1040: * the address be 0.0.0.0.
1041: */
1042: memset(&from, 0, sizeof(from));
1.24 stevesk 1043: fromlen = sizeof(from);
1.1 provos 1044: if (packet_connection_is_on_socket()) {
1045: if (getpeername(packet_get_connection_in(),
1.74 deraadt 1046: (struct sockaddr *)&from, &fromlen) < 0) {
1.1 provos 1047: debug("getpeername: %.100s", strerror(errno));
1.50 markus 1048: cleanup_exit(255);
1.1 provos 1049: }
1050: }
1051: /* Record that there was a login on that tty from the remote host. */
1052: record_login(s->pid, s->tty, pw->pw_name, pw->pw_uid,
1.42 markus 1053: get_remote_name_or_ip(utmp_len, options.use_dns),
1.24 stevesk 1054: (struct sockaddr *)&from, fromlen);
1.1 provos 1055: }
1056:
1057: static void
1058: mm_session_close(Session *s)
1059: {
1.41 djm 1060: debug3("%s: session %d pid %ld", __func__, s->self, (long)s->pid);
1.1 provos 1061: if (s->ttyfd != -1) {
1.86 stevesk 1062: debug3("%s: tty %s ptyfd %d", __func__, s->tty, s->ptyfd);
1.1 provos 1063: session_pty_cleanup2(s);
1064: }
1065: s->used = 0;
1066: }
1067:
1068: int
1.59 avsm 1069: mm_answer_pty(int sock, Buffer *m)
1.1 provos 1070: {
1.11 mouring 1071: extern struct monitor *pmonitor;
1.1 provos 1072: Session *s;
1073: int res, fd0;
1074:
1.14 markus 1075: debug3("%s entering", __func__);
1.1 provos 1076:
1077: buffer_clear(m);
1078: s = session_new();
1079: if (s == NULL)
1080: goto error;
1081: s->authctxt = authctxt;
1082: s->pw = authctxt->pw;
1.11 mouring 1083: s->pid = pmonitor->m_pid;
1.1 provos 1084: res = pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty));
1085: if (res == 0)
1086: goto error;
1087: pty_setowner(authctxt->pw, s->tty);
1088:
1089: buffer_put_int(m, 1);
1090: buffer_put_cstring(m, s->tty);
1091:
1092: /* We need to trick ttyslot */
1093: if (dup2(s->ttyfd, 0) == -1)
1.14 markus 1094: fatal("%s: dup2", __func__);
1.1 provos 1095:
1096: mm_record_login(s, authctxt->pw);
1097:
1098: /* Now we can close the file descriptor again */
1099: close(0);
1.61 dtucker 1100:
1101: /* send messages generated by record_login */
1102: buffer_put_string(m, buffer_ptr(&loginmsg), buffer_len(&loginmsg));
1103: buffer_clear(&loginmsg);
1104:
1105: mm_request_send(sock, MONITOR_ANS_PTY, m);
1106:
1107: mm_send_fd(sock, s->ptyfd);
1108: mm_send_fd(sock, s->ttyfd);
1.1 provos 1109:
1110: /* make sure nothing uses fd 0 */
1111: if ((fd0 = open(_PATH_DEVNULL, O_RDONLY)) < 0)
1.14 markus 1112: fatal("%s: open(/dev/null): %s", __func__, strerror(errno));
1.1 provos 1113: if (fd0 != 0)
1.14 markus 1114: error("%s: fd0 %d != 0", __func__, fd0);
1.1 provos 1115:
1116: /* slave is not needed */
1117: close(s->ttyfd);
1118: s->ttyfd = s->ptyfd;
1119: /* no need to dup() because nobody closes ptyfd */
1120: s->ptymaster = s->ptyfd;
1121:
1.86 stevesk 1122: debug3("%s: tty %s ptyfd %d", __func__, s->tty, s->ttyfd);
1.1 provos 1123:
1124: return (0);
1125:
1126: error:
1127: if (s != NULL)
1128: mm_session_close(s);
1129: buffer_put_int(m, 0);
1.59 avsm 1130: mm_request_send(sock, MONITOR_ANS_PTY, m);
1.1 provos 1131: return (0);
1132: }
1133:
1134: int
1.59 avsm 1135: mm_answer_pty_cleanup(int sock, Buffer *m)
1.1 provos 1136: {
1137: Session *s;
1138: char *tty;
1139:
1.14 markus 1140: debug3("%s entering", __func__);
1.1 provos 1141:
1142: tty = buffer_get_string(m, NULL);
1143: if ((s = session_by_tty(tty)) != NULL)
1144: mm_session_close(s);
1145: buffer_clear(m);
1146: xfree(tty);
1147: return (0);
1148: }
1149:
1150: int
1.59 avsm 1151: mm_answer_sesskey(int sock, Buffer *m)
1.1 provos 1152: {
1153: BIGNUM *p;
1154: int rsafail;
1155:
1156: /* Turn off permissions */
1.62 dtucker 1157: monitor_permit(mon_dispatch, MONITOR_REQ_SESSKEY, 0);
1.1 provos 1158:
1159: if ((p = BN_new()) == NULL)
1.14 markus 1160: fatal("%s: BN_new", __func__);
1.1 provos 1161:
1162: buffer_get_bignum2(m, p);
1163:
1164: rsafail = ssh1_session_key(p);
1165:
1166: buffer_clear(m);
1167: buffer_put_int(m, rsafail);
1168: buffer_put_bignum2(m, p);
1169:
1170: BN_clear_free(p);
1171:
1.59 avsm 1172: mm_request_send(sock, MONITOR_ANS_SESSKEY, m);
1.1 provos 1173:
1174: /* Turn on permissions for sessid passing */
1175: monitor_permit(mon_dispatch, MONITOR_REQ_SESSID, 1);
1176:
1177: return (0);
1178: }
1179:
1180: int
1.59 avsm 1181: mm_answer_sessid(int sock, Buffer *m)
1.1 provos 1182: {
1183: int i;
1184:
1.14 markus 1185: debug3("%s entering", __func__);
1.1 provos 1186:
1187: if (buffer_len(m) != 16)
1.14 markus 1188: fatal("%s: bad ssh1 session id", __func__);
1.1 provos 1189: for (i = 0; i < 16; i++)
1190: session_id[i] = buffer_get_char(m);
1191:
1192: /* Turn on permissions for getpwnam */
1193: monitor_permit(mon_dispatch, MONITOR_REQ_PWNAM, 1);
1194:
1195: return (0);
1196: }
1197:
1198: int
1.59 avsm 1199: mm_answer_rsa_keyallowed(int sock, Buffer *m)
1.1 provos 1200: {
1201: BIGNUM *client_n;
1202: Key *key = NULL;
1.3 markus 1203: u_char *blob = NULL;
1204: u_int blen = 0;
1.1 provos 1205: int allowed = 0;
1206:
1.14 markus 1207: debug3("%s entering", __func__);
1.1 provos 1208:
1.77 dtucker 1209: auth_method = "rsa";
1.12 markus 1210: if (options.rsa_authentication && authctxt->valid) {
1.1 provos 1211: if ((client_n = BN_new()) == NULL)
1.14 markus 1212: fatal("%s: BN_new", __func__);
1.1 provos 1213: buffer_get_bignum2(m, client_n);
1214: allowed = auth_rsa_key_allowed(authctxt->pw, client_n, &key);
1215: BN_clear_free(client_n);
1216: }
1217: buffer_clear(m);
1218: buffer_put_int(m, allowed);
1.32 markus 1219: buffer_put_int(m, forced_command != NULL);
1.1 provos 1220:
1221: /* clear temporarily storage (used by generate challenge) */
1222: monitor_reset_key_state();
1223:
1224: if (allowed && key != NULL) {
1225: key->type = KEY_RSA; /* cheat for key_to_blob */
1226: if (key_to_blob(key, &blob, &blen) == 0)
1.14 markus 1227: fatal("%s: key_to_blob failed", __func__);
1.1 provos 1228: buffer_put_string(m, blob, blen);
1229:
1230: /* Save temporarily for comparison in verify */
1231: key_blob = blob;
1232: key_bloblen = blen;
1233: key_blobtype = MM_RSAUSERKEY;
1.33 markus 1234: }
1235: if (key != NULL)
1.1 provos 1236: key_free(key);
1237:
1238: mm_append_debug(m);
1239:
1.59 avsm 1240: mm_request_send(sock, MONITOR_ANS_RSAKEYALLOWED, m);
1.1 provos 1241:
1242: monitor_permit(mon_dispatch, MONITOR_REQ_RSACHALLENGE, allowed);
1243: monitor_permit(mon_dispatch, MONITOR_REQ_RSARESPONSE, 0);
1244: return (0);
1245: }
1246:
1247: int
1.59 avsm 1248: mm_answer_rsa_challenge(int sock, Buffer *m)
1.1 provos 1249: {
1250: Key *key = NULL;
1.3 markus 1251: u_char *blob;
1252: u_int blen;
1.1 provos 1253:
1.14 markus 1254: debug3("%s entering", __func__);
1.1 provos 1255:
1256: if (!authctxt->valid)
1.14 markus 1257: fatal("%s: authctxt not valid", __func__);
1.1 provos 1258: blob = buffer_get_string(m, &blen);
1259: if (!monitor_allowed_key(blob, blen))
1.14 markus 1260: fatal("%s: bad key, not previously allowed", __func__);
1.1 provos 1261: if (key_blobtype != MM_RSAUSERKEY && key_blobtype != MM_RSAHOSTKEY)
1.14 markus 1262: fatal("%s: key type mismatch", __func__);
1.1 provos 1263: if ((key = key_from_blob(blob, blen)) == NULL)
1.14 markus 1264: fatal("%s: received bad key", __func__);
1.1 provos 1265:
1266: if (ssh1_challenge)
1267: BN_clear_free(ssh1_challenge);
1268: ssh1_challenge = auth_rsa_generate_challenge(key);
1269:
1270: buffer_clear(m);
1271: buffer_put_bignum2(m, ssh1_challenge);
1272:
1.14 markus 1273: debug3("%s sending reply", __func__);
1.59 avsm 1274: mm_request_send(sock, MONITOR_ANS_RSACHALLENGE, m);
1.1 provos 1275:
1276: monitor_permit(mon_dispatch, MONITOR_REQ_RSARESPONSE, 1);
1.33 markus 1277:
1278: xfree(blob);
1279: key_free(key);
1.1 provos 1280: return (0);
1281: }
1282:
1283: int
1.59 avsm 1284: mm_answer_rsa_response(int sock, Buffer *m)
1.1 provos 1285: {
1286: Key *key = NULL;
1.3 markus 1287: u_char *blob, *response;
1288: u_int blen, len;
1289: int success;
1.1 provos 1290:
1.14 markus 1291: debug3("%s entering", __func__);
1.1 provos 1292:
1293: if (!authctxt->valid)
1.14 markus 1294: fatal("%s: authctxt not valid", __func__);
1.1 provos 1295: if (ssh1_challenge == NULL)
1.14 markus 1296: fatal("%s: no ssh1_challenge", __func__);
1.1 provos 1297:
1298: blob = buffer_get_string(m, &blen);
1299: if (!monitor_allowed_key(blob, blen))
1.14 markus 1300: fatal("%s: bad key, not previously allowed", __func__);
1.1 provos 1301: if (key_blobtype != MM_RSAUSERKEY && key_blobtype != MM_RSAHOSTKEY)
1.14 markus 1302: fatal("%s: key type mismatch: %d", __func__, key_blobtype);
1.1 provos 1303: if ((key = key_from_blob(blob, blen)) == NULL)
1.14 markus 1304: fatal("%s: received bad key", __func__);
1.1 provos 1305: response = buffer_get_string(m, &len);
1306: if (len != 16)
1.14 markus 1307: fatal("%s: received bad response to challenge", __func__);
1.1 provos 1308: success = auth_rsa_verify_response(key, ssh1_challenge, response);
1309:
1.33 markus 1310: xfree(blob);
1.1 provos 1311: key_free(key);
1312: xfree(response);
1313:
1314: auth_method = key_blobtype == MM_RSAUSERKEY ? "rsa" : "rhosts-rsa";
1315:
1316: /* reset state */
1317: BN_clear_free(ssh1_challenge);
1318: ssh1_challenge = NULL;
1319: monitor_reset_key_state();
1320:
1321: buffer_clear(m);
1322: buffer_put_int(m, success);
1.59 avsm 1323: mm_request_send(sock, MONITOR_ANS_RSARESPONSE, m);
1.1 provos 1324:
1325: return (success);
1326: }
1327:
1328: int
1.59 avsm 1329: mm_answer_term(int sock, Buffer *req)
1.1 provos 1330: {
1.11 mouring 1331: extern struct monitor *pmonitor;
1.1 provos 1332: int res, status;
1333:
1.14 markus 1334: debug3("%s: tearing down sessions", __func__);
1.1 provos 1335:
1336: /* The child is terminating */
1337: session_destroy_all(&mm_session_close);
1338:
1.11 mouring 1339: while (waitpid(pmonitor->m_pid, &status, 0) == -1)
1.9 markus 1340: if (errno != EINTR)
1341: exit(1);
1.1 provos 1342:
1343: res = WIFEXITED(status) ? WEXITSTATUS(status) : 1;
1344:
1345: /* Terminate process */
1.57 deraadt 1346: exit(res);
1.1 provos 1347: }
1348:
1349: void
1.11 mouring 1350: monitor_apply_keystate(struct monitor *pmonitor)
1.1 provos 1351: {
1352: if (compat20) {
1353: set_newkeys(MODE_IN);
1354: set_newkeys(MODE_OUT);
1355: } else {
1356: packet_set_protocol_flags(child_state.ssh1protoflags);
1.15 markus 1357: packet_set_encryption_key(child_state.ssh1key,
1358: child_state.ssh1keylen, child_state.ssh1cipher);
1359: xfree(child_state.ssh1key);
1.1 provos 1360: }
1361:
1.15 markus 1362: /* for rc4 and other stateful ciphers */
1.1 provos 1363: packet_set_keycontext(MODE_OUT, child_state.keyout);
1364: xfree(child_state.keyout);
1365: packet_set_keycontext(MODE_IN, child_state.keyin);
1366: xfree(child_state.keyin);
1367:
1368: if (!compat20) {
1369: packet_set_iv(MODE_OUT, child_state.ivout);
1370: xfree(child_state.ivout);
1371: packet_set_iv(MODE_IN, child_state.ivin);
1372: xfree(child_state.ivin);
1373: }
1374:
1375: memcpy(&incoming_stream, &child_state.incoming,
1376: sizeof(incoming_stream));
1377: memcpy(&outgoing_stream, &child_state.outgoing,
1378: sizeof(outgoing_stream));
1.3 markus 1379:
1.1 provos 1380: /* Update with new address */
1.16 djm 1381: if (options.compression)
1382: mm_init_compression(pmonitor->m_zlib);
1.1 provos 1383:
1384: /* Network I/O buffers */
1385: /* XXX inefficient for large buffers, need: buffer_init_from_string */
1386: buffer_clear(&input);
1387: buffer_append(&input, child_state.input, child_state.ilen);
1388: memset(child_state.input, 0, child_state.ilen);
1389: xfree(child_state.input);
1390:
1391: buffer_clear(&output);
1392: buffer_append(&output, child_state.output, child_state.olen);
1393: memset(child_state.output, 0, child_state.olen);
1394: xfree(child_state.output);
1395: }
1396:
1.2 markus 1397: static Kex *
1.1 provos 1398: mm_get_kex(Buffer *m)
1399: {
1400: Kex *kex;
1401: void *blob;
1402: u_int bloblen;
1403:
1.75 djm 1404: kex = xcalloc(1, sizeof(*kex));
1.1 provos 1405: kex->session_id = buffer_get_string(m, &kex->session_id_len);
1.13 markus 1406: if ((session_id2 == NULL) ||
1407: (kex->session_id_len != session_id2_len) ||
1408: (memcmp(kex->session_id, session_id2, session_id2_len) != 0))
1409: fatal("mm_get_get: internal error: bad session id");
1.1 provos 1410: kex->we_need = buffer_get_int(m);
1.34 markus 1411: kex->kex[KEX_DH_GRP1_SHA1] = kexdh_server;
1.58 djm 1412: kex->kex[KEX_DH_GRP14_SHA1] = kexdh_server;
1.34 markus 1413: kex->kex[KEX_DH_GEX_SHA1] = kexgex_server;
1.69 djm 1414: kex->kex[KEX_DH_GEX_SHA256] = kexgex_server;
1.1 provos 1415: kex->server = 1;
1416: kex->hostkey_type = buffer_get_int(m);
1417: kex->kex_type = buffer_get_int(m);
1418: blob = buffer_get_string(m, &bloblen);
1419: buffer_init(&kex->my);
1420: buffer_append(&kex->my, blob, bloblen);
1421: xfree(blob);
1422: blob = buffer_get_string(m, &bloblen);
1423: buffer_init(&kex->peer);
1424: buffer_append(&kex->peer, blob, bloblen);
1425: xfree(blob);
1426: kex->done = 1;
1427: kex->flags = buffer_get_int(m);
1428: kex->client_version_string = buffer_get_string(m, NULL);
1429: kex->server_version_string = buffer_get_string(m, NULL);
1430: kex->load_host_key=&get_hostkey_by_type;
1431: kex->host_key_index=&get_hostkey_index;
1432:
1433: return (kex);
1434: }
1435:
1436: /* This function requries careful sanity checking */
1437:
1438: void
1.11 mouring 1439: mm_get_keystate(struct monitor *pmonitor)
1.1 provos 1440: {
1441: Buffer m;
1442: u_char *blob, *p;
1443: u_int bloblen, plen;
1.37 markus 1444: u_int32_t seqnr, packets;
1445: u_int64_t blocks;
1.1 provos 1446:
1.14 markus 1447: debug3("%s: Waiting for new keys", __func__);
1.1 provos 1448:
1449: buffer_init(&m);
1.11 mouring 1450: mm_request_receive_expect(pmonitor->m_sendfd, MONITOR_REQ_KEYEXPORT, &m);
1.1 provos 1451: if (!compat20) {
1452: child_state.ssh1protoflags = buffer_get_int(&m);
1453: child_state.ssh1cipher = buffer_get_int(&m);
1.15 markus 1454: child_state.ssh1key = buffer_get_string(&m,
1455: &child_state.ssh1keylen);
1.1 provos 1456: child_state.ivout = buffer_get_string(&m,
1457: &child_state.ivoutlen);
1458: child_state.ivin = buffer_get_string(&m, &child_state.ivinlen);
1459: goto skip;
1460: } else {
1461: /* Get the Kex for rekeying */
1.11 mouring 1462: *pmonitor->m_pkex = mm_get_kex(&m);
1.1 provos 1463: }
1464:
1465: blob = buffer_get_string(&m, &bloblen);
1466: current_keys[MODE_OUT] = mm_newkeys_from_blob(blob, bloblen);
1467: xfree(blob);
1468:
1.14 markus 1469: debug3("%s: Waiting for second key", __func__);
1.1 provos 1470: blob = buffer_get_string(&m, &bloblen);
1471: current_keys[MODE_IN] = mm_newkeys_from_blob(blob, bloblen);
1472: xfree(blob);
1.3 markus 1473:
1.1 provos 1474: /* Now get sequence numbers for the packets */
1.37 markus 1475: seqnr = buffer_get_int(&m);
1476: blocks = buffer_get_int64(&m);
1477: packets = buffer_get_int(&m);
1478: packet_set_state(MODE_OUT, seqnr, blocks, packets);
1479: seqnr = buffer_get_int(&m);
1480: blocks = buffer_get_int64(&m);
1481: packets = buffer_get_int(&m);
1482: packet_set_state(MODE_IN, seqnr, blocks, packets);
1.1 provos 1483:
1484: skip:
1485: /* Get the key context */
1486: child_state.keyout = buffer_get_string(&m, &child_state.keyoutlen);
1487: child_state.keyin = buffer_get_string(&m, &child_state.keyinlen);
1488:
1.14 markus 1489: debug3("%s: Getting compression state", __func__);
1.1 provos 1490: /* Get compression state */
1491: p = buffer_get_string(&m, &plen);
1492: if (plen != sizeof(child_state.outgoing))
1.14 markus 1493: fatal("%s: bad request size", __func__);
1.1 provos 1494: memcpy(&child_state.outgoing, p, sizeof(child_state.outgoing));
1495: xfree(p);
1496:
1497: p = buffer_get_string(&m, &plen);
1498: if (plen != sizeof(child_state.incoming))
1.14 markus 1499: fatal("%s: bad request size", __func__);
1.1 provos 1500: memcpy(&child_state.incoming, p, sizeof(child_state.incoming));
1501: xfree(p);
1502:
1503: /* Network I/O buffers */
1.14 markus 1504: debug3("%s: Getting Network I/O buffers", __func__);
1.1 provos 1505: child_state.input = buffer_get_string(&m, &child_state.ilen);
1506: child_state.output = buffer_get_string(&m, &child_state.olen);
1507:
1508: buffer_free(&m);
1509: }
1510:
1511:
1512: /* Allocation functions for zlib */
1513: void *
1514: mm_zalloc(struct mm_master *mm, u_int ncount, u_int size)
1515: {
1.30 markus 1516: size_t len = (size_t) size * ncount;
1.1 provos 1517: void *address;
1518:
1.23 millert 1519: if (len == 0 || ncount > SIZE_T_MAX / size)
1.18 deraadt 1520: fatal("%s: mm_zalloc(%u, %u)", __func__, ncount, size);
1521:
1522: address = mm_malloc(mm, len);
1.1 provos 1523:
1524: return (address);
1525: }
1526:
1527: void
1528: mm_zfree(struct mm_master *mm, void *address)
1529: {
1530: mm_free(mm, address);
1531: }
1532:
1533: void
1534: mm_init_compression(struct mm_master *mm)
1535: {
1536: outgoing_stream.zalloc = (alloc_func)mm_zalloc;
1537: outgoing_stream.zfree = (free_func)mm_zfree;
1538: outgoing_stream.opaque = mm;
1539:
1540: incoming_stream.zalloc = (alloc_func)mm_zalloc;
1541: incoming_stream.zfree = (free_func)mm_zfree;
1542: incoming_stream.opaque = mm;
1543: }
1544:
1545: /* XXX */
1546:
1547: #define FD_CLOSEONEXEC(x) do { \
1548: if (fcntl(x, F_SETFD, 1) == -1) \
1549: fatal("fcntl(%d, F_SETFD)", x); \
1550: } while (0)
1551:
1.2 markus 1552: static void
1.1 provos 1553: monitor_socketpair(int *pair)
1.3 markus 1554: {
1.1 provos 1555: if (socketpair(AF_UNIX, SOCK_STREAM, 0, pair) == -1)
1.14 markus 1556: fatal("%s: socketpair", __func__);
1.1 provos 1557: FD_CLOSEONEXEC(pair[0]);
1558: FD_CLOSEONEXEC(pair[1]);
1559: }
1560:
1561: #define MM_MEMSIZE 65536
1562:
1563: struct monitor *
1564: monitor_init(void)
1565: {
1566: struct monitor *mon;
1567: int pair[2];
1568:
1.75 djm 1569: mon = xcalloc(1, sizeof(*mon));
1.1 provos 1570:
1571: monitor_socketpair(pair);
1572:
1573: mon->m_recvfd = pair[0];
1574: mon->m_sendfd = pair[1];
1575:
1576: /* Used to share zlib space across processes */
1.16 djm 1577: if (options.compression) {
1578: mon->m_zback = mm_create(NULL, MM_MEMSIZE);
1579: mon->m_zlib = mm_create(mon->m_zback, 20 * MM_MEMSIZE);
1.1 provos 1580:
1.16 djm 1581: /* Compression needs to share state across borders */
1582: mm_init_compression(mon->m_zlib);
1583: }
1.1 provos 1584:
1585: return mon;
1586: }
1587:
1588: void
1589: monitor_reinit(struct monitor *mon)
1590: {
1591: int pair[2];
1592:
1593: monitor_socketpair(pair);
1594:
1595: mon->m_recvfd = pair[0];
1596: mon->m_sendfd = pair[1];
1597: }
1.46 markus 1598:
1599: #ifdef GSSAPI
1600: int
1.59 avsm 1601: mm_answer_gss_setup_ctx(int sock, Buffer *m)
1.46 markus 1602: {
1.59 avsm 1603: gss_OID_desc goid;
1.46 markus 1604: OM_uint32 major;
1605: u_int len;
1606:
1.59 avsm 1607: goid.elements = buffer_get_string(m, &len);
1608: goid.length = len;
1.46 markus 1609:
1.59 avsm 1610: major = ssh_gssapi_server_ctx(&gsscontext, &goid);
1.46 markus 1611:
1.59 avsm 1612: xfree(goid.elements);
1.46 markus 1613:
1614: buffer_clear(m);
1615: buffer_put_int(m, major);
1616:
1.64 stevesk 1617: mm_request_send(sock, MONITOR_ANS_GSSSETUP, m);
1.46 markus 1618:
1619: /* Now we have a context, enable the step */
1620: monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 1);
1621:
1622: return (0);
1623: }
1624:
1625: int
1.59 avsm 1626: mm_answer_gss_accept_ctx(int sock, Buffer *m)
1.46 markus 1627: {
1628: gss_buffer_desc in;
1629: gss_buffer_desc out = GSS_C_EMPTY_BUFFER;
1.64 stevesk 1630: OM_uint32 major, minor;
1.46 markus 1631: OM_uint32 flags = 0; /* GSI needs this */
1.47 deraadt 1632: u_int len;
1.46 markus 1633:
1.47 deraadt 1634: in.value = buffer_get_string(m, &len);
1635: in.length = len;
1.46 markus 1636: major = ssh_gssapi_accept_ctx(gsscontext, &in, &out, &flags);
1637: xfree(in.value);
1638:
1639: buffer_clear(m);
1640: buffer_put_int(m, major);
1641: buffer_put_string(m, out.value, out.length);
1642: buffer_put_int(m, flags);
1.59 avsm 1643: mm_request_send(sock, MONITOR_ANS_GSSSTEP, m);
1.46 markus 1644:
1645: gss_release_buffer(&minor, &out);
1646:
1.64 stevesk 1647: if (major == GSS_S_COMPLETE) {
1.46 markus 1648: monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 0);
1649: monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
1.52 markus 1650: monitor_permit(mon_dispatch, MONITOR_REQ_GSSCHECKMIC, 1);
1.46 markus 1651: }
1652: return (0);
1653: }
1654:
1655: int
1.59 avsm 1656: mm_answer_gss_checkmic(int sock, Buffer *m)
1.52 markus 1657: {
1658: gss_buffer_desc gssbuf, mic;
1659: OM_uint32 ret;
1660: u_int len;
1.54 djm 1661:
1.52 markus 1662: gssbuf.value = buffer_get_string(m, &len);
1663: gssbuf.length = len;
1664: mic.value = buffer_get_string(m, &len);
1665: mic.length = len;
1.54 djm 1666:
1.52 markus 1667: ret = ssh_gssapi_checkmic(gsscontext, &gssbuf, &mic);
1.54 djm 1668:
1.52 markus 1669: xfree(gssbuf.value);
1670: xfree(mic.value);
1.54 djm 1671:
1.52 markus 1672: buffer_clear(m);
1673: buffer_put_int(m, ret);
1.54 djm 1674:
1.59 avsm 1675: mm_request_send(sock, MONITOR_ANS_GSSCHECKMIC, m);
1.54 djm 1676:
1.52 markus 1677: if (!GSS_ERROR(ret))
1678: monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
1.54 djm 1679:
1.52 markus 1680: return (0);
1681: }
1682:
1683: int
1.59 avsm 1684: mm_answer_gss_userok(int sock, Buffer *m)
1.46 markus 1685: {
1686: int authenticated;
1687:
1688: authenticated = authctxt->valid && ssh_gssapi_userok(authctxt->user);
1689:
1690: buffer_clear(m);
1691: buffer_put_int(m, authenticated);
1692:
1693: debug3("%s: sending result %d", __func__, authenticated);
1.59 avsm 1694: mm_request_send(sock, MONITOR_ANS_GSSUSEROK, m);
1.46 markus 1695:
1.64 stevesk 1696: auth_method = "gssapi-with-mic";
1.46 markus 1697:
1698: /* Monitor loop will terminate if authenticated */
1699: return (authenticated);
1700: }
1701: #endif /* GSSAPI */
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