Annotation of src/usr.bin/ssh/monitor.c, Revision 1.170
1.170 ! markus 1: /* $OpenBSD: monitor.c,v 1.169 2017/05/30 14:10:53 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>
1.95 djm 32: #include <sys/queue.h>
1.1 provos 33:
1.132 markus 34: #ifdef WITH_OPENSSL
1.78 stevesk 35: #include <openssl/dh.h>
1.132 markus 36: #endif
1.78 stevesk 37:
1.81 stevesk 38: #include <errno.h>
1.80 stevesk 39: #include <fcntl.h>
1.159 djm 40: #include <limits.h>
1.65 stevesk 41: #include <paths.h>
1.114 djm 42: #include <poll.h>
1.78 stevesk 43: #include <pwd.h>
1.68 stevesk 44: #include <signal.h>
1.134 djm 45: #include <stdarg.h>
1.142 millert 46: #include <stdint.h>
1.134 djm 47: #include <stdio.h>
1.84 stevesk 48: #include <stdlib.h>
1.82 stevesk 49: #include <string.h>
1.1 provos 50:
1.114 djm 51: #include "atomicio.h"
1.85 deraadt 52: #include "xmalloc.h"
1.1 provos 53: #include "ssh.h"
1.85 deraadt 54: #include "key.h"
55: #include "buffer.h"
56: #include "hostfile.h"
1.1 provos 57: #include "auth.h"
1.85 deraadt 58: #include "cipher.h"
1.1 provos 59: #include "kex.h"
60: #include "dh.h"
1.88 miod 61: #include <zlib.h>
1.1 provos 62: #include "packet.h"
63: #include "auth-options.h"
64: #include "sshpty.h"
65: #include "channels.h"
66: #include "session.h"
67: #include "sshlogin.h"
68: #include "canohost.h"
69: #include "log.h"
1.135 millert 70: #include "misc.h"
1.1 provos 71: #include "servconf.h"
72: #include "monitor.h"
1.85 deraadt 73: #ifdef GSSAPI
74: #include "ssh-gss.h"
75: #endif
1.1 provos 76: #include "monitor_wrap.h"
77: #include "monitor_fdpass.h"
78: #include "compat.h"
79: #include "ssh2.h"
1.127 markus 80: #include "authfd.h"
1.137 djm 81: #include "match.h"
1.138 djm 82: #include "ssherr.h"
1.1 provos 83:
1.46 markus 84: #ifdef GSSAPI
85: static Gssctxt *gsscontext = NULL;
86: #endif
87:
1.1 provos 88: /* Imports */
89: extern ServerOptions options;
90: extern u_int utmp_len;
91: extern u_char session_id[];
92: extern Buffer auth_debug;
93: extern int auth_debug_init;
1.61 dtucker 94: extern Buffer loginmsg;
1.1 provos 95:
96: /* State exported from the child */
1.139 markus 97: static struct sshbuf *child_state;
1.1 provos 98:
1.43 markus 99: /* Functions on the monitor that answer unprivileged requests */
1.1 provos 100:
101: int mm_answer_moduli(int, Buffer *);
102: int mm_answer_sign(int, Buffer *);
103: int mm_answer_pwnamallow(int, Buffer *);
1.10 djm 104: int mm_answer_auth2_read_banner(int, Buffer *);
1.1 provos 105: int mm_answer_authserv(int, Buffer *);
106: int mm_answer_authpassword(int, Buffer *);
107: int mm_answer_bsdauthquery(int, Buffer *);
108: int mm_answer_bsdauthrespond(int, Buffer *);
109: int mm_answer_skeyquery(int, Buffer *);
110: int mm_answer_skeyrespond(int, Buffer *);
111: int mm_answer_keyallowed(int, Buffer *);
112: int mm_answer_keyverify(int, Buffer *);
113: int mm_answer_pty(int, Buffer *);
114: int mm_answer_pty_cleanup(int, Buffer *);
115: int mm_answer_term(int, Buffer *);
116: int mm_answer_rsa_keyallowed(int, Buffer *);
117: int mm_answer_rsa_challenge(int, Buffer *);
118: int mm_answer_rsa_response(int, Buffer *);
119: int mm_answer_sesskey(int, Buffer *);
120: int mm_answer_sessid(int, Buffer *);
121:
1.46 markus 122: #ifdef GSSAPI
123: int mm_answer_gss_setup_ctx(int, Buffer *);
124: int mm_answer_gss_accept_ctx(int, Buffer *);
125: int mm_answer_gss_userok(int, Buffer *);
1.52 markus 126: int mm_answer_gss_checkmic(int, Buffer *);
1.46 markus 127: #endif
1.25 itojun 128:
1.114 djm 129: static int monitor_read_log(struct monitor *);
130:
1.1 provos 131: static Authctxt *authctxt;
1.132 markus 132:
1.1 provos 133: /* local state for key verify */
134: static u_char *key_blob = NULL;
135: static u_int key_bloblen = 0;
136: static int key_blobtype = MM_NOKEY;
1.26 markus 137: static char *hostbased_cuser = NULL;
138: static char *hostbased_chost = NULL;
1.1 provos 139: static char *auth_method = "unknown";
1.119 djm 140: static char *auth_submethod = NULL;
1.44 markus 141: static u_int session_id2_len = 0;
1.13 markus 142: static u_char *session_id2 = NULL;
1.40 markus 143: static pid_t monitor_child_pid;
1.1 provos 144:
145: struct mon_table {
146: enum monitor_reqtype type;
147: int flags;
148: int (*f)(int, Buffer *);
149: };
150:
151: #define MON_ISAUTH 0x0004 /* Required for Authentication */
152: #define MON_AUTHDECIDE 0x0008 /* Decides Authentication */
153: #define MON_ONCE 0x0010 /* Disable after calling */
1.77 dtucker 154: #define MON_ALOG 0x0020 /* Log auth attempt without authenticating */
1.1 provos 155:
156: #define MON_AUTH (MON_ISAUTH|MON_AUTHDECIDE)
157:
158: #define MON_PERMIT 0x1000 /* Request is permitted */
159:
160: struct mon_table mon_dispatch_proto20[] = {
1.132 markus 161: #ifdef WITH_OPENSSL
1.1 provos 162: {MONITOR_REQ_MODULI, MON_ONCE, mm_answer_moduli},
1.132 markus 163: #endif
1.1 provos 164: {MONITOR_REQ_SIGN, MON_ONCE, mm_answer_sign},
165: {MONITOR_REQ_PWNAM, MON_ONCE, mm_answer_pwnamallow},
166: {MONITOR_REQ_AUTHSERV, MON_ONCE, mm_answer_authserv},
1.10 djm 167: {MONITOR_REQ_AUTH2_READ_BANNER, MON_ONCE, mm_answer_auth2_read_banner},
1.1 provos 168: {MONITOR_REQ_AUTHPASSWORD, MON_AUTH, mm_answer_authpassword},
169: {MONITOR_REQ_BSDAUTHQUERY, MON_ISAUTH, mm_answer_bsdauthquery},
1.66 stevesk 170: {MONITOR_REQ_BSDAUTHRESPOND, MON_AUTH, mm_answer_bsdauthrespond},
1.1 provos 171: {MONITOR_REQ_KEYALLOWED, MON_ISAUTH, mm_answer_keyallowed},
172: {MONITOR_REQ_KEYVERIFY, MON_AUTH, mm_answer_keyverify},
1.46 markus 173: #ifdef GSSAPI
174: {MONITOR_REQ_GSSSETUP, MON_ISAUTH, mm_answer_gss_setup_ctx},
1.165 djm 175: {MONITOR_REQ_GSSSTEP, 0, mm_answer_gss_accept_ctx},
176: {MONITOR_REQ_GSSUSEROK, MON_ONCE|MON_AUTHDECIDE, mm_answer_gss_userok},
177: {MONITOR_REQ_GSSCHECKMIC, MON_ONCE, mm_answer_gss_checkmic},
1.46 markus 178: #endif
1.1 provos 179: {0, 0, NULL}
180: };
181:
182: struct mon_table mon_dispatch_postauth20[] = {
1.132 markus 183: #ifdef WITH_OPENSSL
1.1 provos 184: {MONITOR_REQ_MODULI, 0, mm_answer_moduli},
1.132 markus 185: #endif
1.1 provos 186: {MONITOR_REQ_SIGN, 0, mm_answer_sign},
187: {MONITOR_REQ_PTY, 0, mm_answer_pty},
188: {MONITOR_REQ_PTYCLEANUP, 0, mm_answer_pty_cleanup},
189: {MONITOR_REQ_TERM, 0, mm_answer_term},
190: {0, 0, NULL}
191: };
192:
193: struct mon_table *mon_dispatch;
194:
195: /* Specifies if a certain message is allowed at the moment */
196:
197: static void
198: monitor_permit(struct mon_table *ent, enum monitor_reqtype type, int permit)
199: {
200: while (ent->f != NULL) {
201: if (ent->type == type) {
202: ent->flags &= ~MON_PERMIT;
203: ent->flags |= permit ? MON_PERMIT : 0;
204: return;
205: }
206: ent++;
207: }
208: }
209:
210: static void
211: monitor_permit_authentications(int permit)
212: {
213: struct mon_table *ent = mon_dispatch;
214:
215: while (ent->f != NULL) {
216: if (ent->flags & MON_AUTH) {
217: ent->flags &= ~MON_PERMIT;
218: ent->flags |= permit ? MON_PERMIT : 0;
219: }
220: ent++;
221: }
222: }
223:
1.50 markus 224: void
225: monitor_child_preauth(Authctxt *_authctxt, struct monitor *pmonitor)
1.1 provos 226: {
1.167 djm 227: struct ssh *ssh = active_state; /* XXX */
1.1 provos 228: struct mon_table *ent;
1.119 djm 229: int authenticated = 0, partial = 0;
1.1 provos 230:
231: debug3("preauth child monitor started");
232:
1.114 djm 233: close(pmonitor->m_recvfd);
234: close(pmonitor->m_log_sendfd);
235: pmonitor->m_log_sendfd = pmonitor->m_recvfd = -1;
236:
1.50 markus 237: authctxt = _authctxt;
238: memset(authctxt, 0, sizeof(*authctxt));
239:
1.162 markus 240: mon_dispatch = mon_dispatch_proto20;
241: /* Permit requests for moduli and signatures */
242: monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
243: monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
1.1 provos 244:
245: /* The first few requests do not require asynchronous access */
246: while (!authenticated) {
1.119 djm 247: partial = 0;
1.77 dtucker 248: auth_method = "unknown";
1.119 djm 249: auth_submethod = NULL;
1.89 markus 250: authenticated = (monitor_read(pmonitor, mon_dispatch, &ent) == 1);
1.118 djm 251:
252: /* Special handling for multiple required authentications */
253: if (options.num_auth_methods != 0) {
254: if (authenticated &&
255: !auth2_update_methods_lists(authctxt,
1.122 markus 256: auth_method, auth_submethod)) {
1.118 djm 257: debug3("%s: method %s: partial", __func__,
258: auth_method);
259: authenticated = 0;
1.119 djm 260: partial = 1;
1.118 djm 261: }
262: }
263:
1.1 provos 264: if (authenticated) {
265: if (!(ent->flags & MON_AUTHDECIDE))
266: fatal("%s: unexpected authentication from %d",
1.14 markus 267: __func__, ent->type);
1.1 provos 268: if (authctxt->pw->pw_uid == 0 &&
269: !auth_root_allowed(auth_method))
270: authenticated = 0;
271: }
1.77 dtucker 272: if (ent->flags & (MON_AUTHDECIDE|MON_ALOG)) {
1.119 djm 273: auth_log(authctxt, authenticated, partial,
1.125 djm 274: auth_method, auth_submethod);
1.150 djm 275: if (!partial && !authenticated)
1.1 provos 276: authctxt->failures++;
277: }
278: }
279:
280: if (!authctxt->valid)
1.14 markus 281: fatal("%s: authenticated invalid user", __func__);
1.77 dtucker 282: if (strcmp(auth_method, "unknown") == 0)
283: fatal("%s: authentication method name unknown", __func__);
1.1 provos 284:
285: debug("%s: %s has been authenticated by privileged process",
1.14 markus 286: __func__, authctxt->user);
1.167 djm 287: ssh_packet_set_log_preamble(ssh, "user %s", authctxt->user);
1.1 provos 288:
1.11 mouring 289: mm_get_keystate(pmonitor);
1.120 markus 290:
291: /* Drain any buffered messages from the child */
292: while (pmonitor->m_log_recvfd != -1 && monitor_read_log(pmonitor) == 0)
293: ;
1.114 djm 294:
295: close(pmonitor->m_sendfd);
296: close(pmonitor->m_log_recvfd);
297: pmonitor->m_sendfd = pmonitor->m_log_recvfd = -1;
1.1 provos 298: }
299:
1.40 markus 300: static void
301: monitor_set_child_handler(pid_t pid)
302: {
303: monitor_child_pid = pid;
304: }
305:
306: static void
1.59 avsm 307: monitor_child_handler(int sig)
1.40 markus 308: {
1.59 avsm 309: kill(monitor_child_pid, sig);
1.40 markus 310: }
311:
1.1 provos 312: void
1.11 mouring 313: monitor_child_postauth(struct monitor *pmonitor)
1.1 provos 314: {
1.114 djm 315: close(pmonitor->m_recvfd);
316: pmonitor->m_recvfd = -1;
317:
1.40 markus 318: monitor_set_child_handler(pmonitor->m_pid);
319: signal(SIGHUP, &monitor_child_handler);
320: signal(SIGTERM, &monitor_child_handler);
1.91 djm 321: signal(SIGINT, &monitor_child_handler);
1.40 markus 322:
1.162 markus 323: mon_dispatch = mon_dispatch_postauth20;
324:
325: /* Permit requests for moduli and signatures */
326: monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
327: monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
328: monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1);
1.1 provos 329:
330: if (!no_pty_flag) {
331: monitor_permit(mon_dispatch, MONITOR_REQ_PTY, 1);
332: monitor_permit(mon_dispatch, MONITOR_REQ_PTYCLEANUP, 1);
333: }
334:
335: for (;;)
1.11 mouring 336: monitor_read(pmonitor, mon_dispatch, NULL);
1.1 provos 337: }
338:
1.114 djm 339: static int
340: monitor_read_log(struct monitor *pmonitor)
341: {
342: Buffer logmsg;
343: u_int len, level;
344: char *msg;
345:
346: buffer_init(&logmsg);
347:
348: /* Read length */
349: buffer_append_space(&logmsg, 4);
350: if (atomicio(read, pmonitor->m_log_recvfd,
351: buffer_ptr(&logmsg), buffer_len(&logmsg)) != buffer_len(&logmsg)) {
352: if (errno == EPIPE) {
1.116 djm 353: buffer_free(&logmsg);
1.114 djm 354: debug("%s: child log fd closed", __func__);
355: close(pmonitor->m_log_recvfd);
356: pmonitor->m_log_recvfd = -1;
357: return -1;
358: }
359: fatal("%s: log fd read: %s", __func__, strerror(errno));
360: }
361: len = buffer_get_int(&logmsg);
362: if (len <= 4 || len > 8192)
363: fatal("%s: invalid log message length %u", __func__, len);
364:
365: /* Read severity, message */
366: buffer_clear(&logmsg);
367: buffer_append_space(&logmsg, len);
368: if (atomicio(read, pmonitor->m_log_recvfd,
369: buffer_ptr(&logmsg), buffer_len(&logmsg)) != buffer_len(&logmsg))
370: fatal("%s: log fd read: %s", __func__, strerror(errno));
371:
372: /* Log it */
373: level = buffer_get_int(&logmsg);
374: msg = buffer_get_string(&logmsg, NULL);
375: if (log_level_name(level) == NULL)
376: fatal("%s: invalid log level %u (corrupted message?)",
377: __func__, level);
378: do_log2(level, "%s [preauth]", msg);
379:
380: buffer_free(&logmsg);
1.124 djm 381: free(msg);
1.114 djm 382:
383: return 0;
384: }
385:
1.1 provos 386: int
1.11 mouring 387: monitor_read(struct monitor *pmonitor, struct mon_table *ent,
1.1 provos 388: struct mon_table **pent)
389: {
390: Buffer m;
391: int ret;
392: u_char type;
1.114 djm 393: struct pollfd pfd[2];
394:
395: for (;;) {
1.130 tedu 396: memset(&pfd, 0, sizeof(pfd));
1.114 djm 397: pfd[0].fd = pmonitor->m_sendfd;
398: pfd[0].events = POLLIN;
399: pfd[1].fd = pmonitor->m_log_recvfd;
400: pfd[1].events = pfd[1].fd == -1 ? 0 : POLLIN;
1.115 djm 401: if (poll(pfd, pfd[1].fd == -1 ? 1 : 2, -1) == -1) {
402: if (errno == EINTR || errno == EAGAIN)
403: continue;
1.114 djm 404: fatal("%s: poll: %s", __func__, strerror(errno));
1.115 djm 405: }
1.114 djm 406: if (pfd[1].revents) {
407: /*
408: * Drain all log messages before processing next
409: * monitor request.
410: */
411: monitor_read_log(pmonitor);
412: continue;
413: }
414: if (pfd[0].revents)
415: break; /* Continues below */
416: }
1.1 provos 417:
418: buffer_init(&m);
419:
1.11 mouring 420: mm_request_receive(pmonitor->m_sendfd, &m);
1.1 provos 421: type = buffer_get_char(&m);
422:
1.14 markus 423: debug3("%s: checking request %d", __func__, type);
1.1 provos 424:
425: while (ent->f != NULL) {
426: if (ent->type == type)
427: break;
428: ent++;
429: }
430:
431: if (ent->f != NULL) {
432: if (!(ent->flags & MON_PERMIT))
1.14 markus 433: fatal("%s: unpermitted request %d", __func__,
1.1 provos 434: type);
1.11 mouring 435: ret = (*ent->f)(pmonitor->m_sendfd, &m);
1.1 provos 436: buffer_free(&m);
437:
438: /* The child may use this request only once, disable it */
439: if (ent->flags & MON_ONCE) {
1.14 markus 440: debug2("%s: %d used once, disabling now", __func__,
1.1 provos 441: type);
442: ent->flags &= ~MON_PERMIT;
443: }
444:
445: if (pent != NULL)
446: *pent = ent;
1.3 markus 447:
1.1 provos 448: return ret;
449: }
450:
1.14 markus 451: fatal("%s: unsupported request: %d", __func__, type);
1.1 provos 452:
453: /* NOTREACHED */
454: return (-1);
455: }
456:
457: /* allowed key state */
458: static int
459: monitor_allowed_key(u_char *blob, u_int bloblen)
460: {
461: /* make sure key is allowed */
462: if (key_blob == NULL || key_bloblen != bloblen ||
1.108 djm 463: timingsafe_bcmp(key_blob, blob, key_bloblen))
1.1 provos 464: return (0);
465: return (1);
466: }
467:
468: static void
469: monitor_reset_key_state(void)
470: {
471: /* reset state */
1.124 djm 472: free(key_blob);
473: free(hostbased_cuser);
474: free(hostbased_chost);
1.1 provos 475: key_blob = NULL;
476: key_bloblen = 0;
477: key_blobtype = MM_NOKEY;
478: hostbased_cuser = NULL;
479: hostbased_chost = NULL;
480: }
481:
1.132 markus 482: #ifdef WITH_OPENSSL
1.1 provos 483: int
1.59 avsm 484: mm_answer_moduli(int sock, Buffer *m)
1.1 provos 485: {
486: DH *dh;
487: int min, want, max;
488:
489: min = buffer_get_int(m);
490: want = buffer_get_int(m);
491: max = buffer_get_int(m);
492:
493: debug3("%s: got parameters: %d %d %d",
1.14 markus 494: __func__, min, want, max);
1.1 provos 495: /* We need to check here, too, in case the child got corrupted */
496: if (max < min || want < min || max < want)
497: fatal("%s: bad parameters: %d %d %d",
1.14 markus 498: __func__, min, want, max);
1.1 provos 499:
500: buffer_clear(m);
501:
502: dh = choose_dh(min, want, max);
503: if (dh == NULL) {
504: buffer_put_char(m, 0);
505: return (0);
506: } else {
507: /* Send first bignum */
508: buffer_put_char(m, 1);
509: buffer_put_bignum2(m, dh->p);
510: buffer_put_bignum2(m, dh->g);
1.3 markus 511:
1.1 provos 512: DH_free(dh);
513: }
1.59 avsm 514: mm_request_send(sock, MONITOR_ANS_MODULI, m);
1.1 provos 515: return (0);
516: }
1.132 markus 517: #endif
1.1 provos 518:
519: int
1.59 avsm 520: mm_answer_sign(int sock, Buffer *m)
1.1 provos 521: {
1.144 djm 522: struct ssh *ssh = active_state; /* XXX */
1.138 djm 523: extern int auth_sock; /* XXX move to state struct? */
524: struct sshkey *key;
1.157 djm 525: struct sshbuf *sigbuf = NULL;
526: u_char *p = NULL, *signature = NULL;
527: char *alg = NULL;
1.155 markus 528: size_t datlen, siglen, alglen;
1.159 djm 529: int r, is_proof = 0;
530: u_int keyid;
1.145 djm 531: const char proof_req[] = "hostkeys-prove-00@openssh.com";
1.3 markus 532:
1.14 markus 533: debug3("%s", __func__);
1.1 provos 534:
1.138 djm 535: if ((r = sshbuf_get_u32(m, &keyid)) != 0 ||
1.155 markus 536: (r = sshbuf_get_string(m, &p, &datlen)) != 0 ||
537: (r = sshbuf_get_cstring(m, &alg, &alglen)) != 0)
1.138 djm 538: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.159 djm 539: if (keyid > INT_MAX)
540: fatal("%s: invalid key ID", __func__);
1.1 provos 541:
1.69 djm 542: /*
1.110 djm 543: * Supported KEX types use SHA1 (20 bytes), SHA256 (32 bytes),
544: * SHA384 (48 bytes) and SHA512 (64 bytes).
1.144 djm 545: *
546: * Otherwise, verify the signature request is for a hostkey
547: * proof.
548: *
549: * XXX perform similar check for KEX signature requests too?
550: * it's not trivial, since what is signed is the hash, rather
551: * than the full kex structure...
1.69 djm 552: */
1.144 djm 553: if (datlen != 20 && datlen != 32 && datlen != 48 && datlen != 64) {
554: /*
555: * Construct expected hostkey proof and compare it to what
556: * the client sent us.
557: */
558: if (session_id2_len == 0) /* hostkeys is never first */
559: fatal("%s: bad data length: %zu", __func__, datlen);
560: if ((key = get_hostkey_public_by_index(keyid, ssh)) == NULL)
561: fatal("%s: no hostkey for index %d", __func__, keyid);
562: if ((sigbuf = sshbuf_new()) == NULL)
563: fatal("%s: sshbuf_new", __func__);
1.145 djm 564: if ((r = sshbuf_put_cstring(sigbuf, proof_req)) != 0 ||
565: (r = sshbuf_put_string(sigbuf, session_id2,
1.152 jsg 566: session_id2_len)) != 0 ||
1.144 djm 567: (r = sshkey_puts(key, sigbuf)) != 0)
568: fatal("%s: couldn't prepare private key "
569: "proof buffer: %s", __func__, ssh_err(r));
570: if (datlen != sshbuf_len(sigbuf) ||
571: memcmp(p, sshbuf_ptr(sigbuf), sshbuf_len(sigbuf)) != 0)
572: fatal("%s: bad data length: %zu, hostkey proof len %zu",
573: __func__, datlen, sshbuf_len(sigbuf));
574: sshbuf_free(sigbuf);
575: is_proof = 1;
576: }
1.1 provos 577:
1.13 markus 578: /* save session id, it will be passed on the first call */
579: if (session_id2_len == 0) {
580: session_id2_len = datlen;
581: session_id2 = xmalloc(session_id2_len);
582: memcpy(session_id2, p, session_id2_len);
583: }
584:
1.127 markus 585: if ((key = get_hostkey_by_index(keyid)) != NULL) {
1.155 markus 586: if ((r = sshkey_sign(key, &signature, &siglen, p, datlen, alg,
1.138 djm 587: datafellows)) != 0)
588: fatal("%s: sshkey_sign failed: %s",
589: __func__, ssh_err(r));
1.144 djm 590: } else if ((key = get_hostkey_public_by_index(keyid, ssh)) != NULL &&
1.138 djm 591: auth_sock > 0) {
592: if ((r = ssh_agent_sign(auth_sock, key, &signature, &siglen,
1.155 markus 593: p, datlen, alg, datafellows)) != 0) {
1.138 djm 594: fatal("%s: ssh_agent_sign failed: %s",
595: __func__, ssh_err(r));
596: }
1.127 markus 597: } else
1.14 markus 598: fatal("%s: no hostkey from index %d", __func__, keyid);
1.1 provos 599:
1.144 djm 600: debug3("%s: %s signature %p(%zu)", __func__,
601: is_proof ? "KEX" : "hostkey proof", signature, siglen);
1.1 provos 602:
1.138 djm 603: sshbuf_reset(m);
604: if ((r = sshbuf_put_string(m, signature, siglen)) != 0)
605: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.1 provos 606:
1.157 djm 607: free(alg);
1.124 djm 608: free(p);
609: free(signature);
1.1 provos 610:
1.59 avsm 611: mm_request_send(sock, MONITOR_ANS_SIGN, m);
1.1 provos 612:
613: /* Turn on permissions for getpwnam */
614: monitor_permit(mon_dispatch, MONITOR_REQ_PWNAM, 1);
615:
616: return (0);
617: }
618:
619: /* Retrieves the password entry and also checks if the user is permitted */
620:
621: int
1.59 avsm 622: mm_answer_pwnamallow(int sock, Buffer *m)
1.1 provos 623: {
1.167 djm 624: struct ssh *ssh = active_state; /* XXX */
1.60 dtucker 625: char *username;
1.1 provos 626: struct passwd *pwent;
627: int allowed = 0;
1.113 djm 628: u_int i;
1.3 markus 629:
1.14 markus 630: debug3("%s", __func__);
1.1 provos 631:
632: if (authctxt->attempt++ != 0)
1.14 markus 633: fatal("%s: multiple attempts for getpwnam", __func__);
1.1 provos 634:
1.60 dtucker 635: username = buffer_get_string(m, NULL);
1.1 provos 636:
1.60 dtucker 637: pwent = getpwnamallow(username);
1.1 provos 638:
1.60 dtucker 639: authctxt->user = xstrdup(username);
640: setproctitle("%s [priv]", pwent ? username : "unknown");
1.124 djm 641: free(username);
1.1 provos 642:
643: buffer_clear(m);
644:
645: if (pwent == NULL) {
646: buffer_put_char(m, 0);
1.53 djm 647: authctxt->pw = fakepw();
1.1 provos 648: goto out;
649: }
650:
651: allowed = 1;
1.4 markus 652: authctxt->pw = pwent;
1.1 provos 653: authctxt->valid = 1;
654:
655: buffer_put_char(m, 1);
656: buffer_put_string(m, pwent, sizeof(struct passwd));
657: buffer_put_cstring(m, pwent->pw_name);
658: buffer_put_cstring(m, "*");
659: buffer_put_cstring(m, pwent->pw_gecos);
660: buffer_put_cstring(m, pwent->pw_class);
661: buffer_put_cstring(m, pwent->pw_dir);
662: buffer_put_cstring(m, pwent->pw_shell);
1.94 dtucker 663:
664: out:
1.167 djm 665: ssh_packet_set_log_preamble(ssh, "%suser %s",
666: authctxt->valid ? "authenticating" : "invalid ", authctxt->user);
1.90 dtucker 667: buffer_put_string(m, &options, sizeof(options));
1.112 djm 668:
669: #define M_CP_STROPT(x) do { \
670: if (options.x != NULL) \
671: buffer_put_cstring(m, options.x); \
672: } while (0)
1.113 djm 673: #define M_CP_STRARRAYOPT(x, nx) do { \
674: for (i = 0; i < options.nx; i++) \
675: buffer_put_cstring(m, options.x[i]); \
676: } while (0)
1.112 djm 677: /* See comment in servconf.h */
678: COPY_MATCH_STRING_OPTS();
679: #undef M_CP_STROPT
1.113 djm 680: #undef M_CP_STRARRAYOPT
1.118 djm 681:
682: /* Create valid auth method lists */
1.162 markus 683: if (auth2_setup_methods_lists(authctxt) != 0) {
1.118 djm 684: /*
685: * The monitor will continue long enough to let the child
686: * run to it's packet_disconnect(), but it must not allow any
687: * authentication to succeed.
688: */
689: debug("%s: no valid authentication method lists", __func__);
690: }
691:
1.14 markus 692: debug3("%s: sending MONITOR_ANS_PWNAM: %d", __func__, allowed);
1.59 avsm 693: mm_request_send(sock, MONITOR_ANS_PWNAM, m);
1.1 provos 694:
1.162 markus 695: /* Allow service/style information on the auth context */
696: monitor_permit(mon_dispatch, MONITOR_REQ_AUTHSERV, 1);
697: monitor_permit(mon_dispatch, MONITOR_REQ_AUTH2_READ_BANNER, 1);
1.10 djm 698:
699: return (0);
700: }
701:
1.59 avsm 702: int mm_answer_auth2_read_banner(int sock, Buffer *m)
1.10 djm 703: {
704: char *banner;
705:
706: buffer_clear(m);
707: banner = auth2_read_banner();
708: buffer_put_cstring(m, banner != NULL ? banner : "");
1.59 avsm 709: mm_request_send(sock, MONITOR_ANS_AUTH2_READ_BANNER, m);
1.124 djm 710: free(banner);
1.1 provos 711:
712: return (0);
713: }
714:
715: int
1.59 avsm 716: mm_answer_authserv(int sock, Buffer *m)
1.1 provos 717: {
718: monitor_permit_authentications(1);
719:
720: authctxt->service = buffer_get_string(m, NULL);
721: authctxt->style = buffer_get_string(m, NULL);
1.6 stevesk 722: debug3("%s: service=%s, style=%s",
1.14 markus 723: __func__, authctxt->service, authctxt->style);
1.6 stevesk 724:
1.1 provos 725: if (strlen(authctxt->style) == 0) {
1.124 djm 726: free(authctxt->style);
1.1 provos 727: authctxt->style = NULL;
728: }
729:
730: return (0);
731: }
732:
733: int
1.59 avsm 734: mm_answer_authpassword(int sock, Buffer *m)
1.1 provos 735: {
736: static int call_count;
737: char *passwd;
1.22 stevesk 738: int authenticated;
739: u_int plen;
1.1 provos 740:
1.164 djm 741: if (!options.password_authentication)
742: fatal("%s: password authentication not enabled", __func__);
1.1 provos 743: passwd = buffer_get_string(m, &plen);
744: /* Only authenticate if the context is valid */
1.12 markus 745: authenticated = options.password_authentication &&
1.48 markus 746: auth_password(authctxt, passwd);
1.131 djm 747: explicit_bzero(passwd, strlen(passwd));
1.124 djm 748: free(passwd);
1.1 provos 749:
750: buffer_clear(m);
751: buffer_put_int(m, authenticated);
752:
1.14 markus 753: debug3("%s: sending result %d", __func__, authenticated);
1.59 avsm 754: mm_request_send(sock, MONITOR_ANS_AUTHPASSWORD, m);
1.1 provos 755:
756: call_count++;
757: if (plen == 0 && call_count == 1)
758: auth_method = "none";
759: else
760: auth_method = "password";
761:
762: /* Causes monitor loop to terminate if authenticated */
763: return (authenticated);
764: }
765:
766: int
1.59 avsm 767: mm_answer_bsdauthquery(int sock, Buffer *m)
1.1 provos 768: {
769: char *name, *infotxt;
770: u_int numprompts;
771: u_int *echo_on;
772: char **prompts;
1.31 markus 773: u_int success;
1.1 provos 774:
1.164 djm 775: if (!options.kbd_interactive_authentication)
776: fatal("%s: kbd-int authentication not enabled", __func__);
1.31 markus 777: success = bsdauth_query(authctxt, &name, &infotxt, &numprompts,
778: &prompts, &echo_on) < 0 ? 0 : 1;
1.1 provos 779:
780: buffer_clear(m);
1.31 markus 781: buffer_put_int(m, success);
782: if (success)
1.1 provos 783: buffer_put_cstring(m, prompts[0]);
784:
1.31 markus 785: debug3("%s: sending challenge success: %u", __func__, success);
1.59 avsm 786: mm_request_send(sock, MONITOR_ANS_BSDAUTHQUERY, m);
1.1 provos 787:
1.31 markus 788: if (success) {
1.124 djm 789: free(name);
790: free(infotxt);
791: free(prompts);
792: free(echo_on);
1.1 provos 793: }
794:
795: return (0);
796: }
797:
798: int
1.59 avsm 799: mm_answer_bsdauthrespond(int sock, Buffer *m)
1.1 provos 800: {
801: char *response;
802: int authok;
803:
1.164 djm 804: if (!options.kbd_interactive_authentication)
805: fatal("%s: kbd-int authentication not enabled", __func__);
1.154 mmcc 806: if (authctxt->as == NULL)
1.14 markus 807: fatal("%s: no bsd auth session", __func__);
1.1 provos 808:
809: response = buffer_get_string(m, NULL);
1.12 markus 810: authok = options.challenge_response_authentication &&
811: auth_userresponse(authctxt->as, response, 0);
1.1 provos 812: authctxt->as = NULL;
1.14 markus 813: debug3("%s: <%s> = <%d>", __func__, response, authok);
1.124 djm 814: free(response);
1.1 provos 815:
816: buffer_clear(m);
817: buffer_put_int(m, authok);
818:
1.14 markus 819: debug3("%s: sending authenticated: %d", __func__, authok);
1.59 avsm 820: mm_request_send(sock, MONITOR_ANS_BSDAUTHRESPOND, m);
1.1 provos 821:
1.162 markus 822: auth_method = "keyboard-interactive";
823: auth_submethod = "bsdauth";
1.1 provos 824:
825: return (authok != 0);
826: }
827:
828: int
1.59 avsm 829: mm_answer_keyallowed(int sock, Buffer *m)
1.1 provos 830: {
1.168 markus 831: struct sshkey *key;
1.26 markus 832: char *cuser, *chost;
833: u_char *blob;
1.148 djm 834: u_int bloblen, pubkey_auth_attempt;
1.1 provos 835: enum mm_keytype type = 0;
836: int allowed = 0;
837:
1.14 markus 838: debug3("%s entering", __func__);
1.3 markus 839:
1.1 provos 840: type = buffer_get_int(m);
841: cuser = buffer_get_string(m, NULL);
842: chost = buffer_get_string(m, NULL);
843: blob = buffer_get_string(m, &bloblen);
1.148 djm 844: pubkey_auth_attempt = buffer_get_int(m);
1.1 provos 845:
846: key = key_from_blob(blob, bloblen);
847:
1.14 markus 848: debug3("%s: key_from_blob: %p", __func__, key);
1.1 provos 849:
1.51 djm 850: if (key != NULL && authctxt->valid) {
1.137 djm 851: /* These should not make it past the privsep child */
852: if (key_type_plain(key->type) == KEY_RSA &&
853: (datafellows & SSH_BUG_RSASIGMD5) != 0)
854: fatal("%s: passed a SSH_BUG_RSASIGMD5 key", __func__);
855:
1.63 deraadt 856: switch (type) {
1.1 provos 857: case MM_USERKEY:
1.12 markus 858: allowed = options.pubkey_authentication &&
1.136 djm 859: !auth2_userkey_already_used(authctxt, key) &&
1.137 djm 860: match_pattern_list(sshkey_ssh_name(key),
1.149 djm 861: options.pubkey_key_types, 0) == 1 &&
1.148 djm 862: user_key_allowed(authctxt->pw, key,
863: pubkey_auth_attempt);
1.126 djm 864: pubkey_auth_info(authctxt, key, NULL);
1.77 dtucker 865: auth_method = "publickey";
1.148 djm 866: if (options.pubkey_authentication &&
867: (!pubkey_auth_attempt || allowed != 1))
1.97 dtucker 868: auth_clear_options();
1.1 provos 869: break;
870: case MM_HOSTKEY:
1.12 markus 871: allowed = options.hostbased_authentication &&
1.137 djm 872: match_pattern_list(sshkey_ssh_name(key),
1.149 djm 873: options.hostbased_key_types, 0) == 1 &&
1.12 markus 874: hostbased_key_allowed(authctxt->pw,
1.1 provos 875: cuser, chost, key);
1.126 djm 876: pubkey_auth_info(authctxt, key,
877: "client user \"%.100s\", client host \"%.100s\"",
878: cuser, chost);
1.77 dtucker 879: auth_method = "hostbased";
1.1 provos 880: break;
881: default:
1.14 markus 882: fatal("%s: unknown key type %d", __func__, type);
1.1 provos 883: break;
884: }
1.33 markus 885: }
1.161 djm 886:
887: debug3("%s: key %p is %s",
888: __func__, key, allowed ? "allowed" : "not allowed");
889:
1.33 markus 890: if (key != NULL)
1.1 provos 891: key_free(key);
892:
893: /* clear temporarily storage (used by verify) */
894: monitor_reset_key_state();
895:
896: if (allowed) {
897: /* Save temporarily for comparison in verify */
898: key_blob = blob;
899: key_bloblen = bloblen;
900: key_blobtype = type;
901: hostbased_cuser = cuser;
902: hostbased_chost = chost;
1.72 djm 903: } else {
1.77 dtucker 904: /* Log failed attempt */
1.125 djm 905: auth_log(authctxt, 0, 0, auth_method, NULL);
1.124 djm 906: free(blob);
907: free(cuser);
908: free(chost);
1.1 provos 909: }
910:
911: buffer_clear(m);
912: buffer_put_int(m, allowed);
1.32 markus 913: buffer_put_int(m, forced_command != NULL);
1.1 provos 914:
1.59 avsm 915: mm_request_send(sock, MONITOR_ANS_KEYALLOWED, m);
1.1 provos 916:
917: return (0);
918: }
919:
920: static int
921: monitor_valid_userblob(u_char *data, u_int datalen)
922: {
923: Buffer b;
1.159 djm 924: u_char *p;
925: char *userstyle, *cp;
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:
1.1 provos 932: if (datafellows & SSH_OLD_SESSIONID) {
1.13 markus 933: p = buffer_ptr(&b);
934: len = buffer_len(&b);
935: if ((session_id2 == NULL) ||
936: (len < session_id2_len) ||
1.108 djm 937: (timingsafe_bcmp(p, session_id2, session_id2_len) != 0))
1.13 markus 938: fail++;
1.1 provos 939: buffer_consume(&b, session_id2_len);
940: } else {
1.13 markus 941: p = buffer_get_string(&b, &len);
942: if ((session_id2 == NULL) ||
943: (len != session_id2_len) ||
1.108 djm 944: (timingsafe_bcmp(p, session_id2, session_id2_len) != 0))
1.1 provos 945: fail++;
1.124 djm 946: free(p);
1.1 provos 947: }
948: if (buffer_get_char(&b) != SSH2_MSG_USERAUTH_REQUEST)
949: fail++;
1.159 djm 950: cp = buffer_get_cstring(&b, NULL);
1.121 djm 951: xasprintf(&userstyle, "%s%s%s", authctxt->user,
952: authctxt->style ? ":" : "",
953: authctxt->style ? authctxt->style : "");
1.159 djm 954: if (strcmp(userstyle, cp) != 0) {
955: logit("wrong user name passed to monitor: "
956: "expected %s != %.100s", userstyle, cp);
1.1 provos 957: fail++;
958: }
1.124 djm 959: free(userstyle);
1.159 djm 960: free(cp);
1.1 provos 961: buffer_skip_string(&b);
962: if (datafellows & SSH_BUG_PKAUTH) {
963: if (!buffer_get_char(&b))
964: fail++;
965: } else {
1.159 djm 966: cp = buffer_get_cstring(&b, NULL);
967: if (strcmp("publickey", cp) != 0)
1.1 provos 968: fail++;
1.159 djm 969: free(cp);
1.1 provos 970: if (!buffer_get_char(&b))
971: fail++;
972: buffer_skip_string(&b);
973: }
974: buffer_skip_string(&b);
975: if (buffer_len(&b) != 0)
976: fail++;
977: buffer_free(&b);
978: return (fail == 0);
979: }
980:
981: static int
1.26 markus 982: monitor_valid_hostbasedblob(u_char *data, u_int datalen, char *cuser,
983: char *chost)
1.1 provos 984: {
985: Buffer b;
1.121 djm 986: char *p, *userstyle;
1.1 provos 987: u_int len;
988: int fail = 0;
989:
990: buffer_init(&b);
991: buffer_append(&b, data, datalen);
1.3 markus 992:
1.13 markus 993: p = buffer_get_string(&b, &len);
994: if ((session_id2 == NULL) ||
995: (len != session_id2_len) ||
1.108 djm 996: (timingsafe_bcmp(p, session_id2, session_id2_len) != 0))
1.1 provos 997: fail++;
1.124 djm 998: free(p);
1.13 markus 999:
1.1 provos 1000: if (buffer_get_char(&b) != SSH2_MSG_USERAUTH_REQUEST)
1001: fail++;
1.121 djm 1002: p = buffer_get_cstring(&b, NULL);
1003: xasprintf(&userstyle, "%s%s%s", authctxt->user,
1004: authctxt->style ? ":" : "",
1005: authctxt->style ? authctxt->style : "");
1006: if (strcmp(userstyle, p) != 0) {
1.38 itojun 1007: logit("wrong user name passed to monitor: expected %s != %.100s",
1.121 djm 1008: userstyle, p);
1.1 provos 1009: fail++;
1010: }
1.121 djm 1011: free(userstyle);
1.124 djm 1012: free(p);
1.1 provos 1013: buffer_skip_string(&b); /* service */
1.121 djm 1014: p = buffer_get_cstring(&b, NULL);
1.1 provos 1015: if (strcmp(p, "hostbased") != 0)
1016: fail++;
1.124 djm 1017: free(p);
1.1 provos 1018: buffer_skip_string(&b); /* pkalg */
1019: buffer_skip_string(&b); /* pkblob */
1020:
1021: /* verify client host, strip trailing dot if necessary */
1022: p = buffer_get_string(&b, NULL);
1023: if (((len = strlen(p)) > 0) && p[len - 1] == '.')
1024: p[len - 1] = '\0';
1025: if (strcmp(p, chost) != 0)
1026: fail++;
1.124 djm 1027: free(p);
1.1 provos 1028:
1029: /* verify client user */
1030: p = buffer_get_string(&b, NULL);
1031: if (strcmp(p, cuser) != 0)
1032: fail++;
1.124 djm 1033: free(p);
1.1 provos 1034:
1035: if (buffer_len(&b) != 0)
1036: fail++;
1037: buffer_free(&b);
1038: return (fail == 0);
1039: }
1040:
1041: int
1.169 markus 1042: mm_answer_keyverify(int sock, struct sshbuf *m)
1.1 provos 1043: {
1.168 markus 1044: struct sshkey *key;
1.1 provos 1045: u_char *signature, *data, *blob;
1.169 markus 1046: size_t signaturelen, datalen, bloblen;
1047: int r, ret, valid_data = 0, encoded_ret;
1.1 provos 1048:
1.169 markus 1049: if ((r = sshbuf_get_string(m, &blob, &bloblen)) != 0 ||
1050: (r = sshbuf_get_string(m, &signature, &signaturelen)) != 0 ||
1051: (r = sshbuf_get_string(m, &data, &datalen)) != 0)
1052: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.1 provos 1053:
1054: if (hostbased_cuser == NULL || hostbased_chost == NULL ||
1.8 mouring 1055: !monitor_allowed_key(blob, bloblen))
1.14 markus 1056: fatal("%s: bad key, not previously allowed", __func__);
1.1 provos 1057:
1.169 markus 1058: /* XXX use sshkey_froms here; need to change key_blob, etc. */
1059: if ((r = sshkey_from_blob(blob, bloblen, &key)) != 0)
1060: fatal("%s: bad public key blob: %s", __func__, ssh_err(r));
1.1 provos 1061:
1062: switch (key_blobtype) {
1063: case MM_USERKEY:
1064: valid_data = monitor_valid_userblob(data, datalen);
1065: break;
1066: case MM_HOSTKEY:
1067: valid_data = monitor_valid_hostbasedblob(data, datalen,
1068: hostbased_cuser, hostbased_chost);
1069: break;
1070: default:
1071: valid_data = 0;
1072: break;
1073: }
1074: if (!valid_data)
1.14 markus 1075: fatal("%s: bad signature data blob", __func__);
1.1 provos 1076:
1.169 markus 1077: ret = sshkey_verify(key, signature, signaturelen, data, datalen,
1078: active_state->compat);
1.1 provos 1079: debug3("%s: key %p signature %s",
1.169 markus 1080: __func__, key, (ret == 0) ? "verified" : "unverified");
1.1 provos 1081:
1.136 djm 1082: /* If auth was successful then record key to ensure it isn't reused */
1.169 markus 1083: if (ret == 0 && key_blobtype == MM_USERKEY)
1.136 djm 1084: auth2_record_userkey(authctxt, key);
1085: else
1.169 markus 1086: sshkey_free(key);
1.136 djm 1087:
1.124 djm 1088: free(blob);
1089: free(signature);
1090: free(data);
1.1 provos 1091:
1.17 stevesk 1092: auth_method = key_blobtype == MM_USERKEY ? "publickey" : "hostbased";
1093:
1.1 provos 1094: monitor_reset_key_state();
1.3 markus 1095:
1.169 markus 1096: sshbuf_reset(m);
1097:
1098: /* encode ret != 0 as positive integer, since we're sending u32 */
1099: encoded_ret = (ret != 0);
1100: if ((r = sshbuf_put_u32(m, encoded_ret)) != 0)
1101: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.59 avsm 1102: mm_request_send(sock, MONITOR_ANS_KEYVERIFY, m);
1.1 provos 1103:
1.169 markus 1104: return ret == 0;
1.1 provos 1105: }
1106:
1.2 markus 1107: static void
1.1 provos 1108: mm_record_login(Session *s, struct passwd *pw)
1109: {
1.158 djm 1110: struct ssh *ssh = active_state; /* XXX */
1.1 provos 1111: socklen_t fromlen;
1112: struct sockaddr_storage from;
1113:
1114: /*
1115: * Get IP address of client. If the connection is not a socket, let
1116: * the address be 0.0.0.0.
1117: */
1118: memset(&from, 0, sizeof(from));
1.24 stevesk 1119: fromlen = sizeof(from);
1.1 provos 1120: if (packet_connection_is_on_socket()) {
1121: if (getpeername(packet_get_connection_in(),
1.74 deraadt 1122: (struct sockaddr *)&from, &fromlen) < 0) {
1.1 provos 1123: debug("getpeername: %.100s", strerror(errno));
1.50 markus 1124: cleanup_exit(255);
1.1 provos 1125: }
1126: }
1127: /* Record that there was a login on that tty from the remote host. */
1128: record_login(s->pid, s->tty, pw->pw_name, pw->pw_uid,
1.158 djm 1129: session_get_remote_name_or_ip(ssh, utmp_len, options.use_dns),
1.24 stevesk 1130: (struct sockaddr *)&from, fromlen);
1.1 provos 1131: }
1132:
1133: static void
1134: mm_session_close(Session *s)
1135: {
1.41 djm 1136: debug3("%s: session %d pid %ld", __func__, s->self, (long)s->pid);
1.1 provos 1137: if (s->ttyfd != -1) {
1.86 stevesk 1138: debug3("%s: tty %s ptyfd %d", __func__, s->tty, s->ptyfd);
1.1 provos 1139: session_pty_cleanup2(s);
1140: }
1.96 djm 1141: session_unused(s->self);
1.1 provos 1142: }
1143:
1144: int
1.59 avsm 1145: mm_answer_pty(int sock, Buffer *m)
1.1 provos 1146: {
1.11 mouring 1147: extern struct monitor *pmonitor;
1.1 provos 1148: Session *s;
1149: int res, fd0;
1150:
1.14 markus 1151: debug3("%s entering", __func__);
1.1 provos 1152:
1153: buffer_clear(m);
1154: s = session_new();
1155: if (s == NULL)
1156: goto error;
1157: s->authctxt = authctxt;
1158: s->pw = authctxt->pw;
1.11 mouring 1159: s->pid = pmonitor->m_pid;
1.1 provos 1160: res = pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty));
1161: if (res == 0)
1162: goto error;
1163: pty_setowner(authctxt->pw, s->tty);
1164:
1165: buffer_put_int(m, 1);
1166: buffer_put_cstring(m, s->tty);
1167:
1168: /* We need to trick ttyslot */
1169: if (dup2(s->ttyfd, 0) == -1)
1.14 markus 1170: fatal("%s: dup2", __func__);
1.1 provos 1171:
1172: mm_record_login(s, authctxt->pw);
1173:
1174: /* Now we can close the file descriptor again */
1175: close(0);
1.61 dtucker 1176:
1177: /* send messages generated by record_login */
1178: buffer_put_string(m, buffer_ptr(&loginmsg), buffer_len(&loginmsg));
1179: buffer_clear(&loginmsg);
1180:
1181: mm_request_send(sock, MONITOR_ANS_PTY, m);
1182:
1.92 djm 1183: if (mm_send_fd(sock, s->ptyfd) == -1 ||
1184: mm_send_fd(sock, s->ttyfd) == -1)
1185: fatal("%s: send fds failed", __func__);
1.1 provos 1186:
1187: /* make sure nothing uses fd 0 */
1188: if ((fd0 = open(_PATH_DEVNULL, O_RDONLY)) < 0)
1.14 markus 1189: fatal("%s: open(/dev/null): %s", __func__, strerror(errno));
1.1 provos 1190: if (fd0 != 0)
1.14 markus 1191: error("%s: fd0 %d != 0", __func__, fd0);
1.1 provos 1192:
1193: /* slave is not needed */
1194: close(s->ttyfd);
1195: s->ttyfd = s->ptyfd;
1196: /* no need to dup() because nobody closes ptyfd */
1197: s->ptymaster = s->ptyfd;
1198:
1.86 stevesk 1199: debug3("%s: tty %s ptyfd %d", __func__, s->tty, s->ttyfd);
1.1 provos 1200:
1201: return (0);
1202:
1203: error:
1204: if (s != NULL)
1205: mm_session_close(s);
1206: buffer_put_int(m, 0);
1.59 avsm 1207: mm_request_send(sock, MONITOR_ANS_PTY, m);
1.1 provos 1208: return (0);
1209: }
1210:
1211: int
1.59 avsm 1212: mm_answer_pty_cleanup(int sock, Buffer *m)
1.1 provos 1213: {
1214: Session *s;
1215: char *tty;
1216:
1.14 markus 1217: debug3("%s entering", __func__);
1.1 provos 1218:
1219: tty = buffer_get_string(m, NULL);
1220: if ((s = session_by_tty(tty)) != NULL)
1221: mm_session_close(s);
1222: buffer_clear(m);
1.124 djm 1223: free(tty);
1.1 provos 1224: return (0);
1225: }
1226:
1227: int
1.59 avsm 1228: mm_answer_term(int sock, Buffer *req)
1.1 provos 1229: {
1.11 mouring 1230: extern struct monitor *pmonitor;
1.1 provos 1231: int res, status;
1232:
1.14 markus 1233: debug3("%s: tearing down sessions", __func__);
1.1 provos 1234:
1235: /* The child is terminating */
1236: session_destroy_all(&mm_session_close);
1237:
1.11 mouring 1238: while (waitpid(pmonitor->m_pid, &status, 0) == -1)
1.9 markus 1239: if (errno != EINTR)
1240: exit(1);
1.1 provos 1241:
1242: res = WIFEXITED(status) ? WEXITSTATUS(status) : 1;
1243:
1244: /* Terminate process */
1.57 deraadt 1245: exit(res);
1.170 ! markus 1246: }
! 1247:
! 1248: void
! 1249: monitor_clear_keystate(struct monitor *pmonitor)
! 1250: {
! 1251: struct ssh *ssh = active_state; /* XXX */
! 1252:
! 1253: ssh_clear_newkeys(ssh, MODE_IN);
! 1254: ssh_clear_newkeys(ssh, MODE_OUT);
! 1255: sshbuf_free(child_state);
! 1256: child_state = NULL;
1.1 provos 1257: }
1258:
1259: void
1.11 mouring 1260: monitor_apply_keystate(struct monitor *pmonitor)
1.1 provos 1261: {
1.139 markus 1262: struct ssh *ssh = active_state; /* XXX */
1263: struct kex *kex;
1264: int r;
1265:
1266: debug3("%s: packet_set_state", __func__);
1267: if ((r = ssh_packet_set_state(ssh, child_state)) != 0)
1268: fatal("%s: packet_set_state: %s", __func__, ssh_err(r));
1269: sshbuf_free(child_state);
1270: child_state = NULL;
1271:
1.154 mmcc 1272: if ((kex = ssh->kex) != NULL) {
1.139 markus 1273: /* XXX set callbacks */
1.147 djm 1274: #ifdef WITH_OPENSSL
1.139 markus 1275: kex->kex[KEX_DH_GRP1_SHA1] = kexdh_server;
1276: kex->kex[KEX_DH_GRP14_SHA1] = kexdh_server;
1.160 djm 1277: kex->kex[KEX_DH_GRP14_SHA256] = kexdh_server;
1278: kex->kex[KEX_DH_GRP16_SHA512] = kexdh_server;
1279: kex->kex[KEX_DH_GRP18_SHA512] = kexdh_server;
1.139 markus 1280: kex->kex[KEX_DH_GEX_SHA1] = kexgex_server;
1281: kex->kex[KEX_DH_GEX_SHA256] = kexgex_server;
1282: kex->kex[KEX_ECDH_SHA2] = kexecdh_server;
1.147 djm 1283: #endif
1.139 markus 1284: kex->kex[KEX_C25519_SHA256] = kexc25519_server;
1285: kex->load_host_public_key=&get_hostkey_public_by_type;
1286: kex->load_host_private_key=&get_hostkey_private_by_type;
1287: kex->host_key_index=&get_hostkey_index;
1288: kex->sign = sshd_hostkey_sign;
1289: }
1.1 provos 1290: }
1291:
1292: /* This function requries careful sanity checking */
1293:
1294: void
1.11 mouring 1295: mm_get_keystate(struct monitor *pmonitor)
1.1 provos 1296: {
1.14 markus 1297: debug3("%s: Waiting for new keys", __func__);
1.1 provos 1298:
1.139 markus 1299: if ((child_state = sshbuf_new()) == NULL)
1300: fatal("%s: sshbuf_new failed", __func__);
1301: mm_request_receive_expect(pmonitor->m_sendfd, MONITOR_REQ_KEYEXPORT,
1302: child_state);
1303: debug3("%s: GOT new keys", __func__);
1.1 provos 1304: }
1305:
1306:
1307: /* XXX */
1308:
1309: #define FD_CLOSEONEXEC(x) do { \
1.111 djm 1310: if (fcntl(x, F_SETFD, FD_CLOEXEC) == -1) \
1.1 provos 1311: fatal("fcntl(%d, F_SETFD)", x); \
1312: } while (0)
1313:
1.2 markus 1314: static void
1.114 djm 1315: monitor_openfds(struct monitor *mon, int do_logfds)
1.3 markus 1316: {
1.114 djm 1317: int pair[2];
1318:
1.1 provos 1319: if (socketpair(AF_UNIX, SOCK_STREAM, 0, pair) == -1)
1.114 djm 1320: fatal("%s: socketpair: %s", __func__, strerror(errno));
1.1 provos 1321: FD_CLOSEONEXEC(pair[0]);
1322: FD_CLOSEONEXEC(pair[1]);
1.114 djm 1323: mon->m_recvfd = pair[0];
1324: mon->m_sendfd = pair[1];
1325:
1326: if (do_logfds) {
1327: if (pipe(pair) == -1)
1328: fatal("%s: pipe: %s", __func__, strerror(errno));
1329: FD_CLOSEONEXEC(pair[0]);
1330: FD_CLOSEONEXEC(pair[1]);
1331: mon->m_log_recvfd = pair[0];
1332: mon->m_log_sendfd = pair[1];
1333: } else
1334: mon->m_log_recvfd = mon->m_log_sendfd = -1;
1.1 provos 1335: }
1336:
1337: #define MM_MEMSIZE 65536
1338:
1339: struct monitor *
1340: monitor_init(void)
1341: {
1342: struct monitor *mon;
1343:
1.75 djm 1344: mon = xcalloc(1, sizeof(*mon));
1.114 djm 1345: monitor_openfds(mon, 1);
1.1 provos 1346:
1347: return mon;
1348: }
1349:
1350: void
1351: monitor_reinit(struct monitor *mon)
1352: {
1.114 djm 1353: monitor_openfds(mon, 0);
1.1 provos 1354: }
1.46 markus 1355:
1356: #ifdef GSSAPI
1357: int
1.59 avsm 1358: mm_answer_gss_setup_ctx(int sock, Buffer *m)
1.46 markus 1359: {
1.59 avsm 1360: gss_OID_desc goid;
1.46 markus 1361: OM_uint32 major;
1362: u_int len;
1363:
1.164 djm 1364: if (!options.gss_authentication)
1365: fatal("%s: GSSAPI authentication not enabled", __func__);
1366:
1.59 avsm 1367: goid.elements = buffer_get_string(m, &len);
1368: goid.length = len;
1.46 markus 1369:
1.59 avsm 1370: major = ssh_gssapi_server_ctx(&gsscontext, &goid);
1.46 markus 1371:
1.124 djm 1372: free(goid.elements);
1.46 markus 1373:
1374: buffer_clear(m);
1375: buffer_put_int(m, major);
1376:
1.64 stevesk 1377: mm_request_send(sock, MONITOR_ANS_GSSSETUP, m);
1.46 markus 1378:
1379: /* Now we have a context, enable the step */
1380: monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 1);
1381:
1382: return (0);
1383: }
1384:
1385: int
1.59 avsm 1386: mm_answer_gss_accept_ctx(int sock, Buffer *m)
1.46 markus 1387: {
1388: gss_buffer_desc in;
1389: gss_buffer_desc out = GSS_C_EMPTY_BUFFER;
1.64 stevesk 1390: OM_uint32 major, minor;
1.46 markus 1391: OM_uint32 flags = 0; /* GSI needs this */
1.47 deraadt 1392: u_int len;
1.46 markus 1393:
1.164 djm 1394: if (!options.gss_authentication)
1395: fatal("%s: GSSAPI authentication not enabled", __func__);
1396:
1.47 deraadt 1397: in.value = buffer_get_string(m, &len);
1398: in.length = len;
1.46 markus 1399: major = ssh_gssapi_accept_ctx(gsscontext, &in, &out, &flags);
1.124 djm 1400: free(in.value);
1.46 markus 1401:
1402: buffer_clear(m);
1403: buffer_put_int(m, major);
1404: buffer_put_string(m, out.value, out.length);
1405: buffer_put_int(m, flags);
1.59 avsm 1406: mm_request_send(sock, MONITOR_ANS_GSSSTEP, m);
1.46 markus 1407:
1408: gss_release_buffer(&minor, &out);
1409:
1.64 stevesk 1410: if (major == GSS_S_COMPLETE) {
1.46 markus 1411: monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 0);
1412: monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
1.52 markus 1413: monitor_permit(mon_dispatch, MONITOR_REQ_GSSCHECKMIC, 1);
1.46 markus 1414: }
1415: return (0);
1416: }
1417:
1418: int
1.59 avsm 1419: mm_answer_gss_checkmic(int sock, Buffer *m)
1.52 markus 1420: {
1421: gss_buffer_desc gssbuf, mic;
1422: OM_uint32 ret;
1423: u_int len;
1.54 djm 1424:
1.164 djm 1425: if (!options.gss_authentication)
1426: fatal("%s: GSSAPI authentication not enabled", __func__);
1427:
1.52 markus 1428: gssbuf.value = buffer_get_string(m, &len);
1429: gssbuf.length = len;
1430: mic.value = buffer_get_string(m, &len);
1431: mic.length = len;
1.54 djm 1432:
1.52 markus 1433: ret = ssh_gssapi_checkmic(gsscontext, &gssbuf, &mic);
1.54 djm 1434:
1.124 djm 1435: free(gssbuf.value);
1436: free(mic.value);
1.54 djm 1437:
1.52 markus 1438: buffer_clear(m);
1439: buffer_put_int(m, ret);
1.54 djm 1440:
1.59 avsm 1441: mm_request_send(sock, MONITOR_ANS_GSSCHECKMIC, m);
1.54 djm 1442:
1.52 markus 1443: if (!GSS_ERROR(ret))
1444: monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
1.54 djm 1445:
1.52 markus 1446: return (0);
1447: }
1448:
1449: int
1.59 avsm 1450: mm_answer_gss_userok(int sock, Buffer *m)
1.46 markus 1451: {
1452: int authenticated;
1.164 djm 1453:
1454: if (!options.gss_authentication)
1455: fatal("%s: GSSAPI authentication not enabled", __func__);
1.46 markus 1456:
1457: authenticated = authctxt->valid && ssh_gssapi_userok(authctxt->user);
1458:
1459: buffer_clear(m);
1460: buffer_put_int(m, authenticated);
1461:
1462: debug3("%s: sending result %d", __func__, authenticated);
1.59 avsm 1463: mm_request_send(sock, MONITOR_ANS_GSSUSEROK, m);
1.46 markus 1464:
1.64 stevesk 1465: auth_method = "gssapi-with-mic";
1.46 markus 1466:
1467: /* Monitor loop will terminate if authenticated */
1468: return (authenticated);
1469: }
1470: #endif /* GSSAPI */
1.100 djm 1471:
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