Annotation of src/usr.bin/ssh/monitor.c, Revision 1.95
1.95 ! djm 1: /* $OpenBSD: monitor.c,v 1.94 2007/10/29 04:08:08 dtucker 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>
1.95 ! djm 33: #include <sys/queue.h>
1.1 provos 34:
1.78 stevesk 35: #include <openssl/dh.h>
36:
1.81 stevesk 37: #include <errno.h>
1.80 stevesk 38: #include <fcntl.h>
1.65 stevesk 39: #include <paths.h>
1.78 stevesk 40: #include <pwd.h>
1.68 stevesk 41: #include <signal.h>
1.84 stevesk 42: #include <stdlib.h>
1.82 stevesk 43: #include <string.h>
1.1 provos 44:
45:
1.85 deraadt 46: #include "xmalloc.h"
1.1 provos 47: #include "ssh.h"
1.85 deraadt 48: #include "key.h"
49: #include "buffer.h"
50: #include "hostfile.h"
1.1 provos 51: #include "auth.h"
1.85 deraadt 52: #include "cipher.h"
1.1 provos 53: #include "kex.h"
54: #include "dh.h"
1.88 miod 55: #include <zlib.h>
1.1 provos 56: #include "packet.h"
57: #include "auth-options.h"
58: #include "sshpty.h"
59: #include "channels.h"
60: #include "session.h"
61: #include "sshlogin.h"
62: #include "canohost.h"
63: #include "log.h"
64: #include "servconf.h"
65: #include "monitor.h"
66: #include "monitor_mm.h"
1.85 deraadt 67: #ifdef GSSAPI
68: #include "ssh-gss.h"
69: #endif
1.1 provos 70: #include "monitor_wrap.h"
71: #include "monitor_fdpass.h"
72: #include "misc.h"
73: #include "compat.h"
74: #include "ssh2.h"
75:
1.46 markus 76: #ifdef GSSAPI
77: static Gssctxt *gsscontext = NULL;
78: #endif
79:
1.1 provos 80: /* Imports */
81: extern ServerOptions options;
82: extern u_int utmp_len;
83: extern Newkeys *current_keys[];
84: extern z_stream incoming_stream;
85: extern z_stream outgoing_stream;
86: extern u_char session_id[];
87: extern Buffer input, output;
88: extern Buffer auth_debug;
89: extern int auth_debug_init;
1.61 dtucker 90: extern Buffer loginmsg;
1.1 provos 91:
92: /* State exported from the child */
93:
94: struct {
95: z_stream incoming;
96: z_stream outgoing;
97: u_char *keyin;
98: u_int keyinlen;
99: u_char *keyout;
100: u_int keyoutlen;
101: u_char *ivin;
102: u_int ivinlen;
103: u_char *ivout;
104: u_int ivoutlen;
1.15 markus 105: u_char *ssh1key;
106: u_int ssh1keylen;
1.1 provos 107: int ssh1cipher;
108: int ssh1protoflags;
109: u_char *input;
110: u_int ilen;
111: u_char *output;
112: u_int olen;
113: } child_state;
114:
1.43 markus 115: /* Functions on the monitor that answer unprivileged requests */
1.1 provos 116:
117: int mm_answer_moduli(int, Buffer *);
118: int mm_answer_sign(int, Buffer *);
119: int mm_answer_pwnamallow(int, Buffer *);
1.10 djm 120: int mm_answer_auth2_read_banner(int, Buffer *);
1.1 provos 121: int mm_answer_authserv(int, Buffer *);
122: int mm_answer_authpassword(int, Buffer *);
123: int mm_answer_bsdauthquery(int, Buffer *);
124: int mm_answer_bsdauthrespond(int, Buffer *);
125: int mm_answer_skeyquery(int, Buffer *);
126: int mm_answer_skeyrespond(int, Buffer *);
127: int mm_answer_keyallowed(int, Buffer *);
128: int mm_answer_keyverify(int, Buffer *);
129: int mm_answer_pty(int, Buffer *);
130: int mm_answer_pty_cleanup(int, Buffer *);
131: int mm_answer_term(int, Buffer *);
132: int mm_answer_rsa_keyallowed(int, Buffer *);
133: int mm_answer_rsa_challenge(int, Buffer *);
134: int mm_answer_rsa_response(int, Buffer *);
135: int mm_answer_sesskey(int, Buffer *);
136: int mm_answer_sessid(int, Buffer *);
137:
1.46 markus 138: #ifdef GSSAPI
139: int mm_answer_gss_setup_ctx(int, Buffer *);
140: int mm_answer_gss_accept_ctx(int, Buffer *);
141: int mm_answer_gss_userok(int, Buffer *);
1.52 markus 142: int mm_answer_gss_checkmic(int, Buffer *);
1.46 markus 143: #endif
1.25 itojun 144:
1.1 provos 145: static Authctxt *authctxt;
146: static BIGNUM *ssh1_challenge = NULL; /* used for ssh1 rsa auth */
147:
148: /* local state for key verify */
149: static u_char *key_blob = NULL;
150: static u_int key_bloblen = 0;
151: static int key_blobtype = MM_NOKEY;
1.26 markus 152: static char *hostbased_cuser = NULL;
153: static char *hostbased_chost = NULL;
1.1 provos 154: static char *auth_method = "unknown";
1.44 markus 155: static u_int session_id2_len = 0;
1.13 markus 156: static u_char *session_id2 = NULL;
1.40 markus 157: static pid_t monitor_child_pid;
1.1 provos 158:
159: struct mon_table {
160: enum monitor_reqtype type;
161: int flags;
162: int (*f)(int, Buffer *);
163: };
164:
165: #define MON_ISAUTH 0x0004 /* Required for Authentication */
166: #define MON_AUTHDECIDE 0x0008 /* Decides Authentication */
167: #define MON_ONCE 0x0010 /* Disable after calling */
1.77 dtucker 168: #define MON_ALOG 0x0020 /* Log auth attempt without authenticating */
1.1 provos 169:
170: #define MON_AUTH (MON_ISAUTH|MON_AUTHDECIDE)
171:
172: #define MON_PERMIT 0x1000 /* Request is permitted */
173:
174: struct mon_table mon_dispatch_proto20[] = {
175: {MONITOR_REQ_MODULI, MON_ONCE, mm_answer_moduli},
176: {MONITOR_REQ_SIGN, MON_ONCE, mm_answer_sign},
177: {MONITOR_REQ_PWNAM, MON_ONCE, mm_answer_pwnamallow},
178: {MONITOR_REQ_AUTHSERV, MON_ONCE, mm_answer_authserv},
1.10 djm 179: {MONITOR_REQ_AUTH2_READ_BANNER, MON_ONCE, mm_answer_auth2_read_banner},
1.1 provos 180: {MONITOR_REQ_AUTHPASSWORD, MON_AUTH, mm_answer_authpassword},
181: {MONITOR_REQ_BSDAUTHQUERY, MON_ISAUTH, mm_answer_bsdauthquery},
1.66 stevesk 182: {MONITOR_REQ_BSDAUTHRESPOND, MON_AUTH, mm_answer_bsdauthrespond},
1.1 provos 183: {MONITOR_REQ_KEYALLOWED, MON_ISAUTH, mm_answer_keyallowed},
184: {MONITOR_REQ_KEYVERIFY, MON_AUTH, mm_answer_keyverify},
1.46 markus 185: #ifdef GSSAPI
186: {MONITOR_REQ_GSSSETUP, MON_ISAUTH, mm_answer_gss_setup_ctx},
187: {MONITOR_REQ_GSSSTEP, MON_ISAUTH, mm_answer_gss_accept_ctx},
188: {MONITOR_REQ_GSSUSEROK, MON_AUTH, mm_answer_gss_userok},
1.52 markus 189: {MONITOR_REQ_GSSCHECKMIC, MON_ISAUTH, mm_answer_gss_checkmic},
1.46 markus 190: #endif
1.1 provos 191: {0, 0, NULL}
192: };
193:
194: struct mon_table mon_dispatch_postauth20[] = {
195: {MONITOR_REQ_MODULI, 0, mm_answer_moduli},
196: {MONITOR_REQ_SIGN, 0, mm_answer_sign},
197: {MONITOR_REQ_PTY, 0, mm_answer_pty},
198: {MONITOR_REQ_PTYCLEANUP, 0, mm_answer_pty_cleanup},
199: {MONITOR_REQ_TERM, 0, mm_answer_term},
200: {0, 0, NULL}
201: };
202:
203: struct mon_table mon_dispatch_proto15[] = {
204: {MONITOR_REQ_PWNAM, MON_ONCE, mm_answer_pwnamallow},
205: {MONITOR_REQ_SESSKEY, MON_ONCE, mm_answer_sesskey},
206: {MONITOR_REQ_SESSID, MON_ONCE, mm_answer_sessid},
207: {MONITOR_REQ_AUTHPASSWORD, MON_AUTH, mm_answer_authpassword},
1.77 dtucker 208: {MONITOR_REQ_RSAKEYALLOWED, MON_ISAUTH|MON_ALOG, mm_answer_rsa_keyallowed},
209: {MONITOR_REQ_KEYALLOWED, MON_ISAUTH|MON_ALOG, mm_answer_keyallowed},
1.1 provos 210: {MONITOR_REQ_RSACHALLENGE, MON_ONCE, mm_answer_rsa_challenge},
211: {MONITOR_REQ_RSARESPONSE, MON_ONCE|MON_AUTHDECIDE, mm_answer_rsa_response},
212: {MONITOR_REQ_BSDAUTHQUERY, MON_ISAUTH, mm_answer_bsdauthquery},
1.66 stevesk 213: {MONITOR_REQ_BSDAUTHRESPOND, MON_AUTH, mm_answer_bsdauthrespond},
1.1 provos 214: {0, 0, NULL}
215: };
216:
217: struct mon_table mon_dispatch_postauth15[] = {
218: {MONITOR_REQ_PTY, MON_ONCE, mm_answer_pty},
219: {MONITOR_REQ_PTYCLEANUP, MON_ONCE, mm_answer_pty_cleanup},
220: {MONITOR_REQ_TERM, 0, mm_answer_term},
221: {0, 0, NULL}
222: };
223:
224: struct mon_table *mon_dispatch;
225:
226: /* Specifies if a certain message is allowed at the moment */
227:
228: static void
229: monitor_permit(struct mon_table *ent, enum monitor_reqtype type, int permit)
230: {
231: while (ent->f != NULL) {
232: if (ent->type == type) {
233: ent->flags &= ~MON_PERMIT;
234: ent->flags |= permit ? MON_PERMIT : 0;
235: return;
236: }
237: ent++;
238: }
239: }
240:
241: static void
242: monitor_permit_authentications(int permit)
243: {
244: struct mon_table *ent = mon_dispatch;
245:
246: while (ent->f != NULL) {
247: if (ent->flags & MON_AUTH) {
248: ent->flags &= ~MON_PERMIT;
249: ent->flags |= permit ? MON_PERMIT : 0;
250: }
251: ent++;
252: }
253: }
254:
1.50 markus 255: void
256: monitor_child_preauth(Authctxt *_authctxt, struct monitor *pmonitor)
1.1 provos 257: {
258: struct mon_table *ent;
259: int authenticated = 0;
260:
261: debug3("preauth child monitor started");
262:
1.50 markus 263: authctxt = _authctxt;
264: memset(authctxt, 0, sizeof(*authctxt));
265:
1.1 provos 266: if (compat20) {
267: mon_dispatch = mon_dispatch_proto20;
268:
269: /* Permit requests for moduli and signatures */
270: monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
271: monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
272: } else {
273: mon_dispatch = mon_dispatch_proto15;
274:
275: monitor_permit(mon_dispatch, MONITOR_REQ_SESSKEY, 1);
276: }
277:
278: /* The first few requests do not require asynchronous access */
279: while (!authenticated) {
1.77 dtucker 280: auth_method = "unknown";
1.89 markus 281: authenticated = (monitor_read(pmonitor, mon_dispatch, &ent) == 1);
1.1 provos 282: if (authenticated) {
283: if (!(ent->flags & MON_AUTHDECIDE))
284: fatal("%s: unexpected authentication from %d",
1.14 markus 285: __func__, ent->type);
1.1 provos 286: if (authctxt->pw->pw_uid == 0 &&
287: !auth_root_allowed(auth_method))
288: authenticated = 0;
289: }
290:
1.77 dtucker 291: if (ent->flags & (MON_AUTHDECIDE|MON_ALOG)) {
1.1 provos 292: auth_log(authctxt, authenticated, auth_method,
293: compat20 ? " ssh2" : "");
294: if (!authenticated)
295: authctxt->failures++;
296: }
297: }
298:
299: if (!authctxt->valid)
1.14 markus 300: fatal("%s: authenticated invalid user", __func__);
1.77 dtucker 301: if (strcmp(auth_method, "unknown") == 0)
302: fatal("%s: authentication method name unknown", __func__);
1.1 provos 303:
304: debug("%s: %s has been authenticated by privileged process",
1.14 markus 305: __func__, authctxt->user);
1.1 provos 306:
1.11 mouring 307: mm_get_keystate(pmonitor);
1.1 provos 308: }
309:
1.40 markus 310: static void
311: monitor_set_child_handler(pid_t pid)
312: {
313: monitor_child_pid = pid;
314: }
315:
316: static void
1.59 avsm 317: monitor_child_handler(int sig)
1.40 markus 318: {
1.59 avsm 319: kill(monitor_child_pid, sig);
1.40 markus 320: }
321:
1.1 provos 322: void
1.11 mouring 323: monitor_child_postauth(struct monitor *pmonitor)
1.1 provos 324: {
1.40 markus 325: monitor_set_child_handler(pmonitor->m_pid);
326: signal(SIGHUP, &monitor_child_handler);
327: signal(SIGTERM, &monitor_child_handler);
1.91 djm 328: signal(SIGINT, &monitor_child_handler);
1.40 markus 329:
1.1 provos 330: if (compat20) {
331: mon_dispatch = mon_dispatch_postauth20;
332:
333: /* Permit requests for moduli and signatures */
334: monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
335: monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
336: monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1);
337: } else {
338: mon_dispatch = mon_dispatch_postauth15;
339: monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1);
340: }
341: if (!no_pty_flag) {
342: monitor_permit(mon_dispatch, MONITOR_REQ_PTY, 1);
343: monitor_permit(mon_dispatch, MONITOR_REQ_PTYCLEANUP, 1);
344: }
345:
346: for (;;)
1.11 mouring 347: monitor_read(pmonitor, mon_dispatch, NULL);
1.1 provos 348: }
349:
350: void
1.11 mouring 351: monitor_sync(struct monitor *pmonitor)
1.1 provos 352: {
1.16 djm 353: if (options.compression) {
354: /* The member allocation is not visible, so sync it */
355: mm_share_sync(&pmonitor->m_zlib, &pmonitor->m_zback);
356: }
1.1 provos 357: }
358:
359: int
1.11 mouring 360: monitor_read(struct monitor *pmonitor, struct mon_table *ent,
1.1 provos 361: struct mon_table **pent)
362: {
363: Buffer m;
364: int ret;
365: u_char type;
366:
367: buffer_init(&m);
368:
1.11 mouring 369: mm_request_receive(pmonitor->m_sendfd, &m);
1.1 provos 370: type = buffer_get_char(&m);
371:
1.14 markus 372: debug3("%s: checking request %d", __func__, type);
1.1 provos 373:
374: while (ent->f != NULL) {
375: if (ent->type == type)
376: break;
377: ent++;
378: }
379:
380: if (ent->f != NULL) {
381: if (!(ent->flags & MON_PERMIT))
1.14 markus 382: fatal("%s: unpermitted request %d", __func__,
1.1 provos 383: type);
1.11 mouring 384: ret = (*ent->f)(pmonitor->m_sendfd, &m);
1.1 provos 385: buffer_free(&m);
386:
387: /* The child may use this request only once, disable it */
388: if (ent->flags & MON_ONCE) {
1.14 markus 389: debug2("%s: %d used once, disabling now", __func__,
1.1 provos 390: type);
391: ent->flags &= ~MON_PERMIT;
392: }
393:
394: if (pent != NULL)
395: *pent = ent;
1.3 markus 396:
1.1 provos 397: return ret;
398: }
399:
1.14 markus 400: fatal("%s: unsupported request: %d", __func__, type);
1.1 provos 401:
402: /* NOTREACHED */
403: return (-1);
404: }
405:
406: /* allowed key state */
407: static int
408: monitor_allowed_key(u_char *blob, u_int bloblen)
409: {
410: /* make sure key is allowed */
411: if (key_blob == NULL || key_bloblen != bloblen ||
412: memcmp(key_blob, blob, key_bloblen))
413: return (0);
414: return (1);
415: }
416:
417: static void
418: monitor_reset_key_state(void)
419: {
420: /* reset state */
421: if (key_blob != NULL)
422: xfree(key_blob);
423: if (hostbased_cuser != NULL)
424: xfree(hostbased_cuser);
425: if (hostbased_chost != NULL)
426: xfree(hostbased_chost);
427: key_blob = NULL;
428: key_bloblen = 0;
429: key_blobtype = MM_NOKEY;
430: hostbased_cuser = NULL;
431: hostbased_chost = NULL;
432: }
433:
434: int
1.59 avsm 435: mm_answer_moduli(int sock, Buffer *m)
1.1 provos 436: {
437: DH *dh;
438: int min, want, max;
439:
440: min = buffer_get_int(m);
441: want = buffer_get_int(m);
442: max = buffer_get_int(m);
443:
444: debug3("%s: got parameters: %d %d %d",
1.14 markus 445: __func__, min, want, max);
1.1 provos 446: /* We need to check here, too, in case the child got corrupted */
447: if (max < min || want < min || max < want)
448: fatal("%s: bad parameters: %d %d %d",
1.14 markus 449: __func__, min, want, max);
1.1 provos 450:
451: buffer_clear(m);
452:
453: dh = choose_dh(min, want, max);
454: if (dh == NULL) {
455: buffer_put_char(m, 0);
456: return (0);
457: } else {
458: /* Send first bignum */
459: buffer_put_char(m, 1);
460: buffer_put_bignum2(m, dh->p);
461: buffer_put_bignum2(m, dh->g);
1.3 markus 462:
1.1 provos 463: DH_free(dh);
464: }
1.59 avsm 465: mm_request_send(sock, MONITOR_ANS_MODULI, m);
1.1 provos 466: return (0);
467: }
468:
469: int
1.59 avsm 470: mm_answer_sign(int sock, Buffer *m)
1.1 provos 471: {
472: Key *key;
473: u_char *p;
474: u_char *signature;
475: u_int siglen, datlen;
476: int keyid;
1.3 markus 477:
1.14 markus 478: debug3("%s", __func__);
1.1 provos 479:
1.3 markus 480: keyid = buffer_get_int(m);
481: p = buffer_get_string(m, &datlen);
1.1 provos 482:
1.69 djm 483: /*
1.71 deraadt 484: * Supported KEX types will only return SHA1 (20 byte) or
1.69 djm 485: * SHA256 (32 byte) hashes
486: */
487: if (datlen != 20 && datlen != 32)
1.19 deraadt 488: fatal("%s: data length incorrect: %u", __func__, datlen);
1.1 provos 489:
1.13 markus 490: /* save session id, it will be passed on the first call */
491: if (session_id2_len == 0) {
492: session_id2_len = datlen;
493: session_id2 = xmalloc(session_id2_len);
494: memcpy(session_id2, p, session_id2_len);
495: }
496:
1.1 provos 497: if ((key = get_hostkey_by_index(keyid)) == NULL)
1.14 markus 498: fatal("%s: no hostkey from index %d", __func__, keyid);
1.1 provos 499: if (key_sign(key, &signature, &siglen, p, datlen) < 0)
1.14 markus 500: fatal("%s: key_sign failed", __func__);
1.1 provos 501:
1.19 deraadt 502: debug3("%s: signature %p(%u)", __func__, signature, siglen);
1.1 provos 503:
504: buffer_clear(m);
505: buffer_put_string(m, signature, siglen);
506:
507: xfree(p);
508: xfree(signature);
509:
1.59 avsm 510: mm_request_send(sock, MONITOR_ANS_SIGN, m);
1.1 provos 511:
512: /* Turn on permissions for getpwnam */
513: monitor_permit(mon_dispatch, MONITOR_REQ_PWNAM, 1);
514:
515: return (0);
516: }
517:
518: /* Retrieves the password entry and also checks if the user is permitted */
519:
520: int
1.59 avsm 521: mm_answer_pwnamallow(int sock, Buffer *m)
1.1 provos 522: {
1.60 dtucker 523: char *username;
1.1 provos 524: struct passwd *pwent;
525: int allowed = 0;
1.3 markus 526:
1.14 markus 527: debug3("%s", __func__);
1.1 provos 528:
529: if (authctxt->attempt++ != 0)
1.14 markus 530: fatal("%s: multiple attempts for getpwnam", __func__);
1.1 provos 531:
1.60 dtucker 532: username = buffer_get_string(m, NULL);
1.1 provos 533:
1.60 dtucker 534: pwent = getpwnamallow(username);
1.1 provos 535:
1.60 dtucker 536: authctxt->user = xstrdup(username);
537: setproctitle("%s [priv]", pwent ? username : "unknown");
538: xfree(username);
1.1 provos 539:
540: buffer_clear(m);
541:
542: if (pwent == NULL) {
543: buffer_put_char(m, 0);
1.53 djm 544: authctxt->pw = fakepw();
1.1 provos 545: goto out;
546: }
547:
548: allowed = 1;
1.4 markus 549: authctxt->pw = pwent;
1.1 provos 550: authctxt->valid = 1;
551:
552: buffer_put_char(m, 1);
553: buffer_put_string(m, pwent, sizeof(struct passwd));
554: buffer_put_cstring(m, pwent->pw_name);
555: buffer_put_cstring(m, "*");
556: buffer_put_cstring(m, pwent->pw_gecos);
557: buffer_put_cstring(m, pwent->pw_class);
558: buffer_put_cstring(m, pwent->pw_dir);
559: buffer_put_cstring(m, pwent->pw_shell);
1.94 dtucker 560:
561: out:
1.90 dtucker 562: buffer_put_string(m, &options, sizeof(options));
563: if (options.banner != NULL)
564: buffer_put_cstring(m, options.banner);
1.14 markus 565: debug3("%s: sending MONITOR_ANS_PWNAM: %d", __func__, allowed);
1.59 avsm 566: mm_request_send(sock, MONITOR_ANS_PWNAM, m);
1.1 provos 567:
568: /* For SSHv1 allow authentication now */
569: if (!compat20)
570: monitor_permit_authentications(1);
1.10 djm 571: else {
1.1 provos 572: /* Allow service/style information on the auth context */
573: monitor_permit(mon_dispatch, MONITOR_REQ_AUTHSERV, 1);
1.10 djm 574: monitor_permit(mon_dispatch, MONITOR_REQ_AUTH2_READ_BANNER, 1);
575: }
576:
577:
578: return (0);
579: }
580:
1.59 avsm 581: int mm_answer_auth2_read_banner(int sock, Buffer *m)
1.10 djm 582: {
583: char *banner;
584:
585: buffer_clear(m);
586: banner = auth2_read_banner();
587: buffer_put_cstring(m, banner != NULL ? banner : "");
1.59 avsm 588: mm_request_send(sock, MONITOR_ANS_AUTH2_READ_BANNER, m);
1.1 provos 589:
1.10 djm 590: if (banner != NULL)
1.21 deraadt 591: xfree(banner);
1.1 provos 592:
593: return (0);
594: }
595:
596: int
1.59 avsm 597: mm_answer_authserv(int sock, Buffer *m)
1.1 provos 598: {
599: monitor_permit_authentications(1);
600:
601: authctxt->service = buffer_get_string(m, NULL);
602: authctxt->style = buffer_get_string(m, NULL);
1.6 stevesk 603: debug3("%s: service=%s, style=%s",
1.14 markus 604: __func__, authctxt->service, authctxt->style);
1.6 stevesk 605:
1.1 provos 606: if (strlen(authctxt->style) == 0) {
607: xfree(authctxt->style);
608: authctxt->style = NULL;
609: }
610:
611: return (0);
612: }
613:
614: int
1.59 avsm 615: mm_answer_authpassword(int sock, Buffer *m)
1.1 provos 616: {
617: static int call_count;
618: char *passwd;
1.22 stevesk 619: int authenticated;
620: u_int plen;
1.1 provos 621:
622: passwd = buffer_get_string(m, &plen);
623: /* Only authenticate if the context is valid */
1.12 markus 624: authenticated = options.password_authentication &&
1.48 markus 625: auth_password(authctxt, passwd);
1.1 provos 626: memset(passwd, 0, strlen(passwd));
627: xfree(passwd);
628:
629: buffer_clear(m);
630: buffer_put_int(m, authenticated);
631:
1.14 markus 632: debug3("%s: sending result %d", __func__, authenticated);
1.59 avsm 633: mm_request_send(sock, MONITOR_ANS_AUTHPASSWORD, m);
1.1 provos 634:
635: call_count++;
636: if (plen == 0 && call_count == 1)
637: auth_method = "none";
638: else
639: auth_method = "password";
640:
641: /* Causes monitor loop to terminate if authenticated */
642: return (authenticated);
643: }
644:
645: int
1.59 avsm 646: mm_answer_bsdauthquery(int sock, Buffer *m)
1.1 provos 647: {
648: char *name, *infotxt;
649: u_int numprompts;
650: u_int *echo_on;
651: char **prompts;
1.31 markus 652: u_int success;
1.1 provos 653:
1.31 markus 654: success = bsdauth_query(authctxt, &name, &infotxt, &numprompts,
655: &prompts, &echo_on) < 0 ? 0 : 1;
1.1 provos 656:
657: buffer_clear(m);
1.31 markus 658: buffer_put_int(m, success);
659: if (success)
1.1 provos 660: buffer_put_cstring(m, prompts[0]);
661:
1.31 markus 662: debug3("%s: sending challenge success: %u", __func__, success);
1.59 avsm 663: mm_request_send(sock, MONITOR_ANS_BSDAUTHQUERY, m);
1.1 provos 664:
1.31 markus 665: if (success) {
1.1 provos 666: xfree(name);
667: xfree(infotxt);
668: xfree(prompts);
669: xfree(echo_on);
670: }
671:
672: return (0);
673: }
674:
675: int
1.59 avsm 676: mm_answer_bsdauthrespond(int sock, Buffer *m)
1.1 provos 677: {
678: char *response;
679: int authok;
680:
681: if (authctxt->as == 0)
1.14 markus 682: fatal("%s: no bsd auth session", __func__);
1.1 provos 683:
684: response = buffer_get_string(m, NULL);
1.12 markus 685: authok = options.challenge_response_authentication &&
686: auth_userresponse(authctxt->as, response, 0);
1.1 provos 687: authctxt->as = NULL;
1.14 markus 688: debug3("%s: <%s> = <%d>", __func__, response, authok);
1.1 provos 689: xfree(response);
690:
691: buffer_clear(m);
692: buffer_put_int(m, authok);
693:
1.14 markus 694: debug3("%s: sending authenticated: %d", __func__, authok);
1.59 avsm 695: mm_request_send(sock, MONITOR_ANS_BSDAUTHRESPOND, m);
1.1 provos 696:
697: auth_method = "bsdauth";
698:
699: return (authok != 0);
700: }
701:
702:
1.2 markus 703: static void
1.1 provos 704: mm_append_debug(Buffer *m)
705: {
706: if (auth_debug_init && buffer_len(&auth_debug)) {
1.14 markus 707: debug3("%s: Appending debug messages for child", __func__);
1.1 provos 708: buffer_append(m, buffer_ptr(&auth_debug),
709: buffer_len(&auth_debug));
710: buffer_clear(&auth_debug);
711: }
712: }
713:
714: int
1.59 avsm 715: mm_answer_keyallowed(int sock, Buffer *m)
1.1 provos 716: {
717: Key *key;
1.26 markus 718: char *cuser, *chost;
719: u_char *blob;
1.1 provos 720: u_int bloblen;
721: enum mm_keytype type = 0;
722: int allowed = 0;
723:
1.14 markus 724: debug3("%s entering", __func__);
1.3 markus 725:
1.1 provos 726: type = buffer_get_int(m);
727: cuser = buffer_get_string(m, NULL);
728: chost = buffer_get_string(m, NULL);
729: blob = buffer_get_string(m, &bloblen);
730:
731: key = key_from_blob(blob, bloblen);
732:
733: if ((compat20 && type == MM_RSAHOSTKEY) ||
734: (!compat20 && type != MM_RSAHOSTKEY))
1.14 markus 735: fatal("%s: key type and protocol mismatch", __func__);
1.1 provos 736:
1.14 markus 737: debug3("%s: key_from_blob: %p", __func__, key);
1.1 provos 738:
1.51 djm 739: if (key != NULL && authctxt->valid) {
1.63 deraadt 740: switch (type) {
1.1 provos 741: case MM_USERKEY:
1.12 markus 742: allowed = options.pubkey_authentication &&
743: user_key_allowed(authctxt->pw, key);
1.77 dtucker 744: auth_method = "publickey";
1.1 provos 745: break;
746: case MM_HOSTKEY:
1.12 markus 747: allowed = options.hostbased_authentication &&
748: hostbased_key_allowed(authctxt->pw,
1.1 provos 749: cuser, chost, key);
1.77 dtucker 750: auth_method = "hostbased";
1.1 provos 751: break;
752: case MM_RSAHOSTKEY:
753: key->type = KEY_RSA1; /* XXX */
1.12 markus 754: allowed = options.rhosts_rsa_authentication &&
755: auth_rhosts_rsa_key_allowed(authctxt->pw,
1.1 provos 756: cuser, chost, key);
1.77 dtucker 757: auth_method = "rsa";
1.1 provos 758: break;
759: default:
1.14 markus 760: fatal("%s: unknown key type %d", __func__, type);
1.1 provos 761: break;
762: }
1.33 markus 763: }
764: if (key != NULL)
1.1 provos 765: key_free(key);
766:
767: /* clear temporarily storage (used by verify) */
768: monitor_reset_key_state();
769:
770: if (allowed) {
771: /* Save temporarily for comparison in verify */
772: key_blob = blob;
773: key_bloblen = bloblen;
774: key_blobtype = type;
775: hostbased_cuser = cuser;
776: hostbased_chost = chost;
1.72 djm 777: } else {
1.77 dtucker 778: /* Log failed attempt */
779: auth_log(authctxt, 0, auth_method, compat20 ? " ssh2" : "");
1.72 djm 780: xfree(blob);
781: xfree(cuser);
782: xfree(chost);
1.1 provos 783: }
784:
785: debug3("%s: key %p is %s",
1.14 markus 786: __func__, key, allowed ? "allowed" : "disallowed");
1.1 provos 787:
788: buffer_clear(m);
789: buffer_put_int(m, allowed);
1.32 markus 790: buffer_put_int(m, forced_command != NULL);
1.1 provos 791:
792: mm_append_debug(m);
793:
1.59 avsm 794: mm_request_send(sock, MONITOR_ANS_KEYALLOWED, m);
1.1 provos 795:
796: if (type == MM_RSAHOSTKEY)
797: monitor_permit(mon_dispatch, MONITOR_REQ_RSACHALLENGE, allowed);
798:
799: return (0);
800: }
801:
802: static int
803: monitor_valid_userblob(u_char *data, u_int datalen)
804: {
805: Buffer b;
1.26 markus 806: char *p;
1.1 provos 807: u_int len;
808: int fail = 0;
809:
810: buffer_init(&b);
811: buffer_append(&b, data, datalen);
1.3 markus 812:
1.1 provos 813: if (datafellows & SSH_OLD_SESSIONID) {
1.13 markus 814: p = buffer_ptr(&b);
815: len = buffer_len(&b);
816: if ((session_id2 == NULL) ||
817: (len < session_id2_len) ||
818: (memcmp(p, session_id2, session_id2_len) != 0))
819: fail++;
1.1 provos 820: buffer_consume(&b, session_id2_len);
821: } else {
1.13 markus 822: p = buffer_get_string(&b, &len);
823: if ((session_id2 == NULL) ||
824: (len != session_id2_len) ||
825: (memcmp(p, session_id2, session_id2_len) != 0))
1.1 provos 826: fail++;
1.13 markus 827: xfree(p);
1.1 provos 828: }
829: if (buffer_get_char(&b) != SSH2_MSG_USERAUTH_REQUEST)
830: fail++;
831: p = buffer_get_string(&b, NULL);
832: if (strcmp(authctxt->user, p) != 0) {
1.38 itojun 833: logit("wrong user name passed to monitor: expected %s != %.100s",
1.1 provos 834: authctxt->user, p);
835: fail++;
836: }
837: xfree(p);
838: buffer_skip_string(&b);
839: if (datafellows & SSH_BUG_PKAUTH) {
840: if (!buffer_get_char(&b))
841: fail++;
842: } else {
843: p = buffer_get_string(&b, NULL);
844: if (strcmp("publickey", p) != 0)
845: fail++;
846: xfree(p);
847: if (!buffer_get_char(&b))
848: fail++;
849: buffer_skip_string(&b);
850: }
851: buffer_skip_string(&b);
852: if (buffer_len(&b) != 0)
853: fail++;
854: buffer_free(&b);
855: return (fail == 0);
856: }
857:
858: static int
1.26 markus 859: monitor_valid_hostbasedblob(u_char *data, u_int datalen, char *cuser,
860: char *chost)
1.1 provos 861: {
862: Buffer b;
1.26 markus 863: char *p;
1.1 provos 864: u_int len;
865: int fail = 0;
866:
867: buffer_init(&b);
868: buffer_append(&b, data, datalen);
1.3 markus 869:
1.13 markus 870: p = buffer_get_string(&b, &len);
871: if ((session_id2 == NULL) ||
872: (len != session_id2_len) ||
873: (memcmp(p, session_id2, session_id2_len) != 0))
1.1 provos 874: fail++;
1.13 markus 875: xfree(p);
876:
1.1 provos 877: if (buffer_get_char(&b) != SSH2_MSG_USERAUTH_REQUEST)
878: fail++;
879: p = buffer_get_string(&b, NULL);
880: if (strcmp(authctxt->user, p) != 0) {
1.38 itojun 881: logit("wrong user name passed to monitor: expected %s != %.100s",
1.1 provos 882: authctxt->user, p);
883: fail++;
884: }
885: xfree(p);
886: buffer_skip_string(&b); /* service */
887: p = buffer_get_string(&b, NULL);
888: if (strcmp(p, "hostbased") != 0)
889: fail++;
890: xfree(p);
891: buffer_skip_string(&b); /* pkalg */
892: buffer_skip_string(&b); /* pkblob */
893:
894: /* verify client host, strip trailing dot if necessary */
895: p = buffer_get_string(&b, NULL);
896: if (((len = strlen(p)) > 0) && p[len - 1] == '.')
897: p[len - 1] = '\0';
898: if (strcmp(p, chost) != 0)
899: fail++;
900: xfree(p);
901:
902: /* verify client user */
903: p = buffer_get_string(&b, NULL);
904: if (strcmp(p, cuser) != 0)
905: fail++;
906: xfree(p);
907:
908: if (buffer_len(&b) != 0)
909: fail++;
910: buffer_free(&b);
911: return (fail == 0);
912: }
913:
914: int
1.59 avsm 915: mm_answer_keyverify(int sock, Buffer *m)
1.1 provos 916: {
917: Key *key;
918: u_char *signature, *data, *blob;
919: u_int signaturelen, datalen, bloblen;
920: int verified = 0;
921: int valid_data = 0;
922:
923: blob = buffer_get_string(m, &bloblen);
924: signature = buffer_get_string(m, &signaturelen);
925: data = buffer_get_string(m, &datalen);
926:
927: if (hostbased_cuser == NULL || hostbased_chost == NULL ||
1.8 mouring 928: !monitor_allowed_key(blob, bloblen))
1.14 markus 929: fatal("%s: bad key, not previously allowed", __func__);
1.1 provos 930:
931: key = key_from_blob(blob, bloblen);
932: if (key == NULL)
1.14 markus 933: fatal("%s: bad public key blob", __func__);
1.1 provos 934:
935: switch (key_blobtype) {
936: case MM_USERKEY:
937: valid_data = monitor_valid_userblob(data, datalen);
938: break;
939: case MM_HOSTKEY:
940: valid_data = monitor_valid_hostbasedblob(data, datalen,
941: hostbased_cuser, hostbased_chost);
942: break;
943: default:
944: valid_data = 0;
945: break;
946: }
947: if (!valid_data)
1.14 markus 948: fatal("%s: bad signature data blob", __func__);
1.1 provos 949:
950: verified = key_verify(key, signature, signaturelen, data, datalen);
951: debug3("%s: key %p signature %s",
1.89 markus 952: __func__, key, (verified == 1) ? "verified" : "unverified");
1.1 provos 953:
954: key_free(key);
955: xfree(blob);
956: xfree(signature);
957: xfree(data);
958:
1.17 stevesk 959: auth_method = key_blobtype == MM_USERKEY ? "publickey" : "hostbased";
960:
1.1 provos 961: monitor_reset_key_state();
1.3 markus 962:
1.1 provos 963: buffer_clear(m);
964: buffer_put_int(m, verified);
1.59 avsm 965: mm_request_send(sock, MONITOR_ANS_KEYVERIFY, m);
1.1 provos 966:
1.89 markus 967: return (verified == 1);
1.1 provos 968: }
969:
1.2 markus 970: static void
1.1 provos 971: mm_record_login(Session *s, struct passwd *pw)
972: {
973: socklen_t fromlen;
974: struct sockaddr_storage from;
975:
976: /*
977: * Get IP address of client. If the connection is not a socket, let
978: * the address be 0.0.0.0.
979: */
980: memset(&from, 0, sizeof(from));
1.24 stevesk 981: fromlen = sizeof(from);
1.1 provos 982: if (packet_connection_is_on_socket()) {
983: if (getpeername(packet_get_connection_in(),
1.74 deraadt 984: (struct sockaddr *)&from, &fromlen) < 0) {
1.1 provos 985: debug("getpeername: %.100s", strerror(errno));
1.50 markus 986: cleanup_exit(255);
1.1 provos 987: }
988: }
989: /* Record that there was a login on that tty from the remote host. */
990: record_login(s->pid, s->tty, pw->pw_name, pw->pw_uid,
1.42 markus 991: get_remote_name_or_ip(utmp_len, options.use_dns),
1.24 stevesk 992: (struct sockaddr *)&from, fromlen);
1.1 provos 993: }
994:
995: static void
996: mm_session_close(Session *s)
997: {
1.41 djm 998: debug3("%s: session %d pid %ld", __func__, s->self, (long)s->pid);
1.1 provos 999: if (s->ttyfd != -1) {
1.86 stevesk 1000: debug3("%s: tty %s ptyfd %d", __func__, s->tty, s->ptyfd);
1.1 provos 1001: session_pty_cleanup2(s);
1002: }
1003: s->used = 0;
1004: }
1005:
1006: int
1.59 avsm 1007: mm_answer_pty(int sock, Buffer *m)
1.1 provos 1008: {
1.11 mouring 1009: extern struct monitor *pmonitor;
1.1 provos 1010: Session *s;
1011: int res, fd0;
1012:
1.14 markus 1013: debug3("%s entering", __func__);
1.1 provos 1014:
1015: buffer_clear(m);
1016: s = session_new();
1017: if (s == NULL)
1018: goto error;
1019: s->authctxt = authctxt;
1020: s->pw = authctxt->pw;
1.11 mouring 1021: s->pid = pmonitor->m_pid;
1.1 provos 1022: res = pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty));
1023: if (res == 0)
1024: goto error;
1025: pty_setowner(authctxt->pw, s->tty);
1026:
1027: buffer_put_int(m, 1);
1028: buffer_put_cstring(m, s->tty);
1029:
1030: /* We need to trick ttyslot */
1031: if (dup2(s->ttyfd, 0) == -1)
1.14 markus 1032: fatal("%s: dup2", __func__);
1.1 provos 1033:
1034: mm_record_login(s, authctxt->pw);
1035:
1036: /* Now we can close the file descriptor again */
1037: close(0);
1.61 dtucker 1038:
1039: /* send messages generated by record_login */
1040: buffer_put_string(m, buffer_ptr(&loginmsg), buffer_len(&loginmsg));
1041: buffer_clear(&loginmsg);
1042:
1043: mm_request_send(sock, MONITOR_ANS_PTY, m);
1044:
1.92 djm 1045: if (mm_send_fd(sock, s->ptyfd) == -1 ||
1046: mm_send_fd(sock, s->ttyfd) == -1)
1047: fatal("%s: send fds failed", __func__);
1.1 provos 1048:
1049: /* make sure nothing uses fd 0 */
1050: if ((fd0 = open(_PATH_DEVNULL, O_RDONLY)) < 0)
1.14 markus 1051: fatal("%s: open(/dev/null): %s", __func__, strerror(errno));
1.1 provos 1052: if (fd0 != 0)
1.14 markus 1053: error("%s: fd0 %d != 0", __func__, fd0);
1.1 provos 1054:
1055: /* slave is not needed */
1056: close(s->ttyfd);
1057: s->ttyfd = s->ptyfd;
1058: /* no need to dup() because nobody closes ptyfd */
1059: s->ptymaster = s->ptyfd;
1060:
1.86 stevesk 1061: debug3("%s: tty %s ptyfd %d", __func__, s->tty, s->ttyfd);
1.1 provos 1062:
1063: return (0);
1064:
1065: error:
1066: if (s != NULL)
1067: mm_session_close(s);
1068: buffer_put_int(m, 0);
1.59 avsm 1069: mm_request_send(sock, MONITOR_ANS_PTY, m);
1.1 provos 1070: return (0);
1071: }
1072:
1073: int
1.59 avsm 1074: mm_answer_pty_cleanup(int sock, Buffer *m)
1.1 provos 1075: {
1076: Session *s;
1077: char *tty;
1078:
1.14 markus 1079: debug3("%s entering", __func__);
1.1 provos 1080:
1081: tty = buffer_get_string(m, NULL);
1082: if ((s = session_by_tty(tty)) != NULL)
1083: mm_session_close(s);
1084: buffer_clear(m);
1085: xfree(tty);
1086: return (0);
1087: }
1088:
1089: int
1.59 avsm 1090: mm_answer_sesskey(int sock, Buffer *m)
1.1 provos 1091: {
1092: BIGNUM *p;
1093: int rsafail;
1094:
1095: /* Turn off permissions */
1.62 dtucker 1096: monitor_permit(mon_dispatch, MONITOR_REQ_SESSKEY, 0);
1.1 provos 1097:
1098: if ((p = BN_new()) == NULL)
1.14 markus 1099: fatal("%s: BN_new", __func__);
1.1 provos 1100:
1101: buffer_get_bignum2(m, p);
1102:
1103: rsafail = ssh1_session_key(p);
1104:
1105: buffer_clear(m);
1106: buffer_put_int(m, rsafail);
1107: buffer_put_bignum2(m, p);
1108:
1109: BN_clear_free(p);
1110:
1.59 avsm 1111: mm_request_send(sock, MONITOR_ANS_SESSKEY, m);
1.1 provos 1112:
1113: /* Turn on permissions for sessid passing */
1114: monitor_permit(mon_dispatch, MONITOR_REQ_SESSID, 1);
1115:
1116: return (0);
1117: }
1118:
1119: int
1.59 avsm 1120: mm_answer_sessid(int sock, Buffer *m)
1.1 provos 1121: {
1122: int i;
1123:
1.14 markus 1124: debug3("%s entering", __func__);
1.1 provos 1125:
1126: if (buffer_len(m) != 16)
1.14 markus 1127: fatal("%s: bad ssh1 session id", __func__);
1.1 provos 1128: for (i = 0; i < 16; i++)
1129: session_id[i] = buffer_get_char(m);
1130:
1131: /* Turn on permissions for getpwnam */
1132: monitor_permit(mon_dispatch, MONITOR_REQ_PWNAM, 1);
1133:
1134: return (0);
1135: }
1136:
1137: int
1.59 avsm 1138: mm_answer_rsa_keyallowed(int sock, Buffer *m)
1.1 provos 1139: {
1140: BIGNUM *client_n;
1141: Key *key = NULL;
1.3 markus 1142: u_char *blob = NULL;
1143: u_int blen = 0;
1.1 provos 1144: int allowed = 0;
1145:
1.14 markus 1146: debug3("%s entering", __func__);
1.1 provos 1147:
1.77 dtucker 1148: auth_method = "rsa";
1.12 markus 1149: if (options.rsa_authentication && authctxt->valid) {
1.1 provos 1150: if ((client_n = BN_new()) == NULL)
1.14 markus 1151: fatal("%s: BN_new", __func__);
1.1 provos 1152: buffer_get_bignum2(m, client_n);
1153: allowed = auth_rsa_key_allowed(authctxt->pw, client_n, &key);
1154: BN_clear_free(client_n);
1155: }
1156: buffer_clear(m);
1157: buffer_put_int(m, allowed);
1.32 markus 1158: buffer_put_int(m, forced_command != NULL);
1.1 provos 1159:
1160: /* clear temporarily storage (used by generate challenge) */
1161: monitor_reset_key_state();
1162:
1163: if (allowed && key != NULL) {
1164: key->type = KEY_RSA; /* cheat for key_to_blob */
1165: if (key_to_blob(key, &blob, &blen) == 0)
1.14 markus 1166: fatal("%s: key_to_blob failed", __func__);
1.1 provos 1167: buffer_put_string(m, blob, blen);
1168:
1169: /* Save temporarily for comparison in verify */
1170: key_blob = blob;
1171: key_bloblen = blen;
1172: key_blobtype = MM_RSAUSERKEY;
1.33 markus 1173: }
1174: if (key != NULL)
1.1 provos 1175: key_free(key);
1176:
1177: mm_append_debug(m);
1178:
1.59 avsm 1179: mm_request_send(sock, MONITOR_ANS_RSAKEYALLOWED, m);
1.1 provos 1180:
1181: monitor_permit(mon_dispatch, MONITOR_REQ_RSACHALLENGE, allowed);
1182: monitor_permit(mon_dispatch, MONITOR_REQ_RSARESPONSE, 0);
1183: return (0);
1184: }
1185:
1186: int
1.59 avsm 1187: mm_answer_rsa_challenge(int sock, Buffer *m)
1.1 provos 1188: {
1189: Key *key = NULL;
1.3 markus 1190: u_char *blob;
1191: u_int blen;
1.1 provos 1192:
1.14 markus 1193: debug3("%s entering", __func__);
1.1 provos 1194:
1195: if (!authctxt->valid)
1.14 markus 1196: fatal("%s: authctxt not valid", __func__);
1.1 provos 1197: blob = buffer_get_string(m, &blen);
1198: if (!monitor_allowed_key(blob, blen))
1.14 markus 1199: fatal("%s: bad key, not previously allowed", __func__);
1.1 provos 1200: if (key_blobtype != MM_RSAUSERKEY && key_blobtype != MM_RSAHOSTKEY)
1.14 markus 1201: fatal("%s: key type mismatch", __func__);
1.1 provos 1202: if ((key = key_from_blob(blob, blen)) == NULL)
1.14 markus 1203: fatal("%s: received bad key", __func__);
1.1 provos 1204:
1205: if (ssh1_challenge)
1206: BN_clear_free(ssh1_challenge);
1207: ssh1_challenge = auth_rsa_generate_challenge(key);
1208:
1209: buffer_clear(m);
1210: buffer_put_bignum2(m, ssh1_challenge);
1211:
1.14 markus 1212: debug3("%s sending reply", __func__);
1.59 avsm 1213: mm_request_send(sock, MONITOR_ANS_RSACHALLENGE, m);
1.1 provos 1214:
1215: monitor_permit(mon_dispatch, MONITOR_REQ_RSARESPONSE, 1);
1.33 markus 1216:
1217: xfree(blob);
1218: key_free(key);
1.1 provos 1219: return (0);
1220: }
1221:
1222: int
1.59 avsm 1223: mm_answer_rsa_response(int sock, Buffer *m)
1.1 provos 1224: {
1225: Key *key = NULL;
1.3 markus 1226: u_char *blob, *response;
1227: u_int blen, len;
1228: int success;
1.1 provos 1229:
1.14 markus 1230: debug3("%s entering", __func__);
1.1 provos 1231:
1232: if (!authctxt->valid)
1.14 markus 1233: fatal("%s: authctxt not valid", __func__);
1.1 provos 1234: if (ssh1_challenge == NULL)
1.14 markus 1235: fatal("%s: no ssh1_challenge", __func__);
1.1 provos 1236:
1237: blob = buffer_get_string(m, &blen);
1238: if (!monitor_allowed_key(blob, blen))
1.14 markus 1239: fatal("%s: bad key, not previously allowed", __func__);
1.1 provos 1240: if (key_blobtype != MM_RSAUSERKEY && key_blobtype != MM_RSAHOSTKEY)
1.14 markus 1241: fatal("%s: key type mismatch: %d", __func__, key_blobtype);
1.1 provos 1242: if ((key = key_from_blob(blob, blen)) == NULL)
1.14 markus 1243: fatal("%s: received bad key", __func__);
1.1 provos 1244: response = buffer_get_string(m, &len);
1245: if (len != 16)
1.14 markus 1246: fatal("%s: received bad response to challenge", __func__);
1.1 provos 1247: success = auth_rsa_verify_response(key, ssh1_challenge, response);
1248:
1.33 markus 1249: xfree(blob);
1.1 provos 1250: key_free(key);
1251: xfree(response);
1252:
1253: auth_method = key_blobtype == MM_RSAUSERKEY ? "rsa" : "rhosts-rsa";
1254:
1255: /* reset state */
1256: BN_clear_free(ssh1_challenge);
1257: ssh1_challenge = NULL;
1258: monitor_reset_key_state();
1259:
1260: buffer_clear(m);
1261: buffer_put_int(m, success);
1.59 avsm 1262: mm_request_send(sock, MONITOR_ANS_RSARESPONSE, m);
1.1 provos 1263:
1264: return (success);
1265: }
1266:
1267: int
1.59 avsm 1268: mm_answer_term(int sock, Buffer *req)
1.1 provos 1269: {
1.11 mouring 1270: extern struct monitor *pmonitor;
1.1 provos 1271: int res, status;
1272:
1.14 markus 1273: debug3("%s: tearing down sessions", __func__);
1.1 provos 1274:
1275: /* The child is terminating */
1276: session_destroy_all(&mm_session_close);
1277:
1.11 mouring 1278: while (waitpid(pmonitor->m_pid, &status, 0) == -1)
1.9 markus 1279: if (errno != EINTR)
1280: exit(1);
1.1 provos 1281:
1282: res = WIFEXITED(status) ? WEXITSTATUS(status) : 1;
1283:
1284: /* Terminate process */
1.57 deraadt 1285: exit(res);
1.1 provos 1286: }
1287:
1288: void
1.11 mouring 1289: monitor_apply_keystate(struct monitor *pmonitor)
1.1 provos 1290: {
1291: if (compat20) {
1292: set_newkeys(MODE_IN);
1293: set_newkeys(MODE_OUT);
1294: } else {
1295: packet_set_protocol_flags(child_state.ssh1protoflags);
1.15 markus 1296: packet_set_encryption_key(child_state.ssh1key,
1297: child_state.ssh1keylen, child_state.ssh1cipher);
1298: xfree(child_state.ssh1key);
1.1 provos 1299: }
1300:
1.15 markus 1301: /* for rc4 and other stateful ciphers */
1.1 provos 1302: packet_set_keycontext(MODE_OUT, child_state.keyout);
1303: xfree(child_state.keyout);
1304: packet_set_keycontext(MODE_IN, child_state.keyin);
1305: xfree(child_state.keyin);
1306:
1307: if (!compat20) {
1308: packet_set_iv(MODE_OUT, child_state.ivout);
1309: xfree(child_state.ivout);
1310: packet_set_iv(MODE_IN, child_state.ivin);
1311: xfree(child_state.ivin);
1312: }
1313:
1314: memcpy(&incoming_stream, &child_state.incoming,
1315: sizeof(incoming_stream));
1316: memcpy(&outgoing_stream, &child_state.outgoing,
1317: sizeof(outgoing_stream));
1.3 markus 1318:
1.1 provos 1319: /* Update with new address */
1.16 djm 1320: if (options.compression)
1321: mm_init_compression(pmonitor->m_zlib);
1.1 provos 1322:
1323: /* Network I/O buffers */
1324: /* XXX inefficient for large buffers, need: buffer_init_from_string */
1325: buffer_clear(&input);
1326: buffer_append(&input, child_state.input, child_state.ilen);
1327: memset(child_state.input, 0, child_state.ilen);
1328: xfree(child_state.input);
1329:
1330: buffer_clear(&output);
1331: buffer_append(&output, child_state.output, child_state.olen);
1332: memset(child_state.output, 0, child_state.olen);
1333: xfree(child_state.output);
1334: }
1335:
1.2 markus 1336: static Kex *
1.1 provos 1337: mm_get_kex(Buffer *m)
1338: {
1339: Kex *kex;
1340: void *blob;
1341: u_int bloblen;
1342:
1.75 djm 1343: kex = xcalloc(1, sizeof(*kex));
1.1 provos 1344: kex->session_id = buffer_get_string(m, &kex->session_id_len);
1.13 markus 1345: if ((session_id2 == NULL) ||
1346: (kex->session_id_len != session_id2_len) ||
1347: (memcmp(kex->session_id, session_id2, session_id2_len) != 0))
1348: fatal("mm_get_get: internal error: bad session id");
1.1 provos 1349: kex->we_need = buffer_get_int(m);
1.34 markus 1350: kex->kex[KEX_DH_GRP1_SHA1] = kexdh_server;
1.58 djm 1351: kex->kex[KEX_DH_GRP14_SHA1] = kexdh_server;
1.34 markus 1352: kex->kex[KEX_DH_GEX_SHA1] = kexgex_server;
1.69 djm 1353: kex->kex[KEX_DH_GEX_SHA256] = kexgex_server;
1.1 provos 1354: kex->server = 1;
1355: kex->hostkey_type = buffer_get_int(m);
1356: kex->kex_type = buffer_get_int(m);
1357: blob = buffer_get_string(m, &bloblen);
1358: buffer_init(&kex->my);
1359: buffer_append(&kex->my, blob, bloblen);
1360: xfree(blob);
1361: blob = buffer_get_string(m, &bloblen);
1362: buffer_init(&kex->peer);
1363: buffer_append(&kex->peer, blob, bloblen);
1364: xfree(blob);
1365: kex->done = 1;
1366: kex->flags = buffer_get_int(m);
1367: kex->client_version_string = buffer_get_string(m, NULL);
1368: kex->server_version_string = buffer_get_string(m, NULL);
1369: kex->load_host_key=&get_hostkey_by_type;
1370: kex->host_key_index=&get_hostkey_index;
1371:
1372: return (kex);
1373: }
1374:
1375: /* This function requries careful sanity checking */
1376:
1377: void
1.11 mouring 1378: mm_get_keystate(struct monitor *pmonitor)
1.1 provos 1379: {
1380: Buffer m;
1381: u_char *blob, *p;
1382: u_int bloblen, plen;
1.37 markus 1383: u_int32_t seqnr, packets;
1384: u_int64_t blocks;
1.1 provos 1385:
1.14 markus 1386: debug3("%s: Waiting for new keys", __func__);
1.1 provos 1387:
1388: buffer_init(&m);
1.11 mouring 1389: mm_request_receive_expect(pmonitor->m_sendfd, MONITOR_REQ_KEYEXPORT, &m);
1.1 provos 1390: if (!compat20) {
1391: child_state.ssh1protoflags = buffer_get_int(&m);
1392: child_state.ssh1cipher = buffer_get_int(&m);
1.15 markus 1393: child_state.ssh1key = buffer_get_string(&m,
1394: &child_state.ssh1keylen);
1.1 provos 1395: child_state.ivout = buffer_get_string(&m,
1396: &child_state.ivoutlen);
1397: child_state.ivin = buffer_get_string(&m, &child_state.ivinlen);
1398: goto skip;
1399: } else {
1400: /* Get the Kex for rekeying */
1.11 mouring 1401: *pmonitor->m_pkex = mm_get_kex(&m);
1.1 provos 1402: }
1403:
1404: blob = buffer_get_string(&m, &bloblen);
1405: current_keys[MODE_OUT] = mm_newkeys_from_blob(blob, bloblen);
1406: xfree(blob);
1407:
1.14 markus 1408: debug3("%s: Waiting for second key", __func__);
1.1 provos 1409: blob = buffer_get_string(&m, &bloblen);
1410: current_keys[MODE_IN] = mm_newkeys_from_blob(blob, bloblen);
1411: xfree(blob);
1.3 markus 1412:
1.1 provos 1413: /* Now get sequence numbers for the packets */
1.37 markus 1414: seqnr = buffer_get_int(&m);
1415: blocks = buffer_get_int64(&m);
1416: packets = buffer_get_int(&m);
1417: packet_set_state(MODE_OUT, seqnr, blocks, packets);
1418: seqnr = buffer_get_int(&m);
1419: blocks = buffer_get_int64(&m);
1420: packets = buffer_get_int(&m);
1421: packet_set_state(MODE_IN, seqnr, blocks, packets);
1.1 provos 1422:
1423: skip:
1424: /* Get the key context */
1425: child_state.keyout = buffer_get_string(&m, &child_state.keyoutlen);
1426: child_state.keyin = buffer_get_string(&m, &child_state.keyinlen);
1427:
1.14 markus 1428: debug3("%s: Getting compression state", __func__);
1.1 provos 1429: /* Get compression state */
1430: p = buffer_get_string(&m, &plen);
1431: if (plen != sizeof(child_state.outgoing))
1.14 markus 1432: fatal("%s: bad request size", __func__);
1.1 provos 1433: memcpy(&child_state.outgoing, p, sizeof(child_state.outgoing));
1434: xfree(p);
1435:
1436: p = buffer_get_string(&m, &plen);
1437: if (plen != sizeof(child_state.incoming))
1.14 markus 1438: fatal("%s: bad request size", __func__);
1.1 provos 1439: memcpy(&child_state.incoming, p, sizeof(child_state.incoming));
1440: xfree(p);
1441:
1442: /* Network I/O buffers */
1.14 markus 1443: debug3("%s: Getting Network I/O buffers", __func__);
1.1 provos 1444: child_state.input = buffer_get_string(&m, &child_state.ilen);
1445: child_state.output = buffer_get_string(&m, &child_state.olen);
1446:
1447: buffer_free(&m);
1448: }
1449:
1450:
1451: /* Allocation functions for zlib */
1452: void *
1453: mm_zalloc(struct mm_master *mm, u_int ncount, u_int size)
1454: {
1.30 markus 1455: size_t len = (size_t) size * ncount;
1.1 provos 1456: void *address;
1457:
1.23 millert 1458: if (len == 0 || ncount > SIZE_T_MAX / size)
1.18 deraadt 1459: fatal("%s: mm_zalloc(%u, %u)", __func__, ncount, size);
1460:
1461: address = mm_malloc(mm, len);
1.1 provos 1462:
1463: return (address);
1464: }
1465:
1466: void
1467: mm_zfree(struct mm_master *mm, void *address)
1468: {
1469: mm_free(mm, address);
1470: }
1471:
1472: void
1473: mm_init_compression(struct mm_master *mm)
1474: {
1475: outgoing_stream.zalloc = (alloc_func)mm_zalloc;
1476: outgoing_stream.zfree = (free_func)mm_zfree;
1477: outgoing_stream.opaque = mm;
1478:
1479: incoming_stream.zalloc = (alloc_func)mm_zalloc;
1480: incoming_stream.zfree = (free_func)mm_zfree;
1481: incoming_stream.opaque = mm;
1482: }
1483:
1484: /* XXX */
1485:
1486: #define FD_CLOSEONEXEC(x) do { \
1487: if (fcntl(x, F_SETFD, 1) == -1) \
1488: fatal("fcntl(%d, F_SETFD)", x); \
1489: } while (0)
1490:
1.2 markus 1491: static void
1.1 provos 1492: monitor_socketpair(int *pair)
1.3 markus 1493: {
1.1 provos 1494: if (socketpair(AF_UNIX, SOCK_STREAM, 0, pair) == -1)
1.14 markus 1495: fatal("%s: socketpair", __func__);
1.1 provos 1496: FD_CLOSEONEXEC(pair[0]);
1497: FD_CLOSEONEXEC(pair[1]);
1498: }
1499:
1500: #define MM_MEMSIZE 65536
1501:
1502: struct monitor *
1503: monitor_init(void)
1504: {
1505: struct monitor *mon;
1506: int pair[2];
1507:
1.75 djm 1508: mon = xcalloc(1, sizeof(*mon));
1.1 provos 1509:
1510: monitor_socketpair(pair);
1511:
1512: mon->m_recvfd = pair[0];
1513: mon->m_sendfd = pair[1];
1514:
1515: /* Used to share zlib space across processes */
1.16 djm 1516: if (options.compression) {
1517: mon->m_zback = mm_create(NULL, MM_MEMSIZE);
1518: mon->m_zlib = mm_create(mon->m_zback, 20 * MM_MEMSIZE);
1.1 provos 1519:
1.16 djm 1520: /* Compression needs to share state across borders */
1521: mm_init_compression(mon->m_zlib);
1522: }
1.1 provos 1523:
1524: return mon;
1525: }
1526:
1527: void
1528: monitor_reinit(struct monitor *mon)
1529: {
1530: int pair[2];
1531:
1532: monitor_socketpair(pair);
1533:
1534: mon->m_recvfd = pair[0];
1535: mon->m_sendfd = pair[1];
1536: }
1.46 markus 1537:
1538: #ifdef GSSAPI
1539: int
1.59 avsm 1540: mm_answer_gss_setup_ctx(int sock, Buffer *m)
1.46 markus 1541: {
1.59 avsm 1542: gss_OID_desc goid;
1.46 markus 1543: OM_uint32 major;
1544: u_int len;
1545:
1.59 avsm 1546: goid.elements = buffer_get_string(m, &len);
1547: goid.length = len;
1.46 markus 1548:
1.59 avsm 1549: major = ssh_gssapi_server_ctx(&gsscontext, &goid);
1.46 markus 1550:
1.59 avsm 1551: xfree(goid.elements);
1.46 markus 1552:
1553: buffer_clear(m);
1554: buffer_put_int(m, major);
1555:
1.64 stevesk 1556: mm_request_send(sock, MONITOR_ANS_GSSSETUP, m);
1.46 markus 1557:
1558: /* Now we have a context, enable the step */
1559: monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 1);
1560:
1561: return (0);
1562: }
1563:
1564: int
1.59 avsm 1565: mm_answer_gss_accept_ctx(int sock, Buffer *m)
1.46 markus 1566: {
1567: gss_buffer_desc in;
1568: gss_buffer_desc out = GSS_C_EMPTY_BUFFER;
1.64 stevesk 1569: OM_uint32 major, minor;
1.46 markus 1570: OM_uint32 flags = 0; /* GSI needs this */
1.47 deraadt 1571: u_int len;
1.46 markus 1572:
1.47 deraadt 1573: in.value = buffer_get_string(m, &len);
1574: in.length = len;
1.46 markus 1575: major = ssh_gssapi_accept_ctx(gsscontext, &in, &out, &flags);
1576: xfree(in.value);
1577:
1578: buffer_clear(m);
1579: buffer_put_int(m, major);
1580: buffer_put_string(m, out.value, out.length);
1581: buffer_put_int(m, flags);
1.59 avsm 1582: mm_request_send(sock, MONITOR_ANS_GSSSTEP, m);
1.46 markus 1583:
1584: gss_release_buffer(&minor, &out);
1585:
1.64 stevesk 1586: if (major == GSS_S_COMPLETE) {
1.46 markus 1587: monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 0);
1588: monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
1.52 markus 1589: monitor_permit(mon_dispatch, MONITOR_REQ_GSSCHECKMIC, 1);
1.46 markus 1590: }
1591: return (0);
1592: }
1593:
1594: int
1.59 avsm 1595: mm_answer_gss_checkmic(int sock, Buffer *m)
1.52 markus 1596: {
1597: gss_buffer_desc gssbuf, mic;
1598: OM_uint32 ret;
1599: u_int len;
1.54 djm 1600:
1.52 markus 1601: gssbuf.value = buffer_get_string(m, &len);
1602: gssbuf.length = len;
1603: mic.value = buffer_get_string(m, &len);
1604: mic.length = len;
1.54 djm 1605:
1.52 markus 1606: ret = ssh_gssapi_checkmic(gsscontext, &gssbuf, &mic);
1.54 djm 1607:
1.52 markus 1608: xfree(gssbuf.value);
1609: xfree(mic.value);
1.54 djm 1610:
1.52 markus 1611: buffer_clear(m);
1612: buffer_put_int(m, ret);
1.54 djm 1613:
1.59 avsm 1614: mm_request_send(sock, MONITOR_ANS_GSSCHECKMIC, m);
1.54 djm 1615:
1.52 markus 1616: if (!GSS_ERROR(ret))
1617: monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
1.54 djm 1618:
1.52 markus 1619: return (0);
1620: }
1621:
1622: int
1.59 avsm 1623: mm_answer_gss_userok(int sock, Buffer *m)
1.46 markus 1624: {
1625: int authenticated;
1626:
1627: authenticated = authctxt->valid && ssh_gssapi_userok(authctxt->user);
1628:
1629: buffer_clear(m);
1630: buffer_put_int(m, authenticated);
1631:
1632: debug3("%s: sending result %d", __func__, authenticated);
1.59 avsm 1633: mm_request_send(sock, MONITOR_ANS_GSSUSEROK, m);
1.46 markus 1634:
1.64 stevesk 1635: auth_method = "gssapi-with-mic";
1.46 markus 1636:
1637: /* Monitor loop will terminate if authenticated */
1638: return (authenticated);
1639: }
1640: #endif /* GSSAPI */
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