Annotation of src/usr.bin/ssh/monitor.c, Revision 1.166
1.166 ! djm 1: /* $OpenBSD: monitor.c,v 1.165 2016/09/05 13:57:31 djm Exp $ */
1.1 provos 2: /*
3: * Copyright 2002 Niels Provos <provos@citi.umich.edu>
4: * Copyright 2002 Markus Friedl <markus@openbsd.org>
5: * All rights reserved.
6: *
7: * Redistribution and use in source and binary forms, with or without
8: * modification, are permitted provided that the following conditions
9: * are met:
10: * 1. Redistributions of source code must retain the above copyright
11: * notice, this list of conditions and the following disclaimer.
12: * 2. Redistributions in binary form must reproduce the above copyright
13: * notice, this list of conditions and the following disclaimer in the
14: * documentation and/or other materials provided with the distribution.
15: *
16: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26: */
27:
1.67 stevesk 28: #include <sys/types.h>
29: #include <sys/wait.h>
1.79 stevesk 30: #include <sys/socket.h>
1.85 deraadt 31: #include <sys/tree.h>
1.95 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: {
227: struct mon_table *ent;
1.119 djm 228: int authenticated = 0, partial = 0;
1.1 provos 229:
230: debug3("preauth child monitor started");
231:
1.114 djm 232: close(pmonitor->m_recvfd);
233: close(pmonitor->m_log_sendfd);
234: pmonitor->m_log_sendfd = pmonitor->m_recvfd = -1;
235:
1.50 markus 236: authctxt = _authctxt;
237: memset(authctxt, 0, sizeof(*authctxt));
238:
1.162 markus 239: mon_dispatch = mon_dispatch_proto20;
240: /* Permit requests for moduli and signatures */
241: monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
242: monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
1.1 provos 243:
244: /* The first few requests do not require asynchronous access */
245: while (!authenticated) {
1.119 djm 246: partial = 0;
1.77 dtucker 247: auth_method = "unknown";
1.119 djm 248: auth_submethod = NULL;
1.89 markus 249: authenticated = (monitor_read(pmonitor, mon_dispatch, &ent) == 1);
1.118 djm 250:
251: /* Special handling for multiple required authentications */
252: if (options.num_auth_methods != 0) {
253: if (authenticated &&
254: !auth2_update_methods_lists(authctxt,
1.122 markus 255: auth_method, auth_submethod)) {
1.118 djm 256: debug3("%s: method %s: partial", __func__,
257: auth_method);
258: authenticated = 0;
1.119 djm 259: partial = 1;
1.118 djm 260: }
261: }
262:
1.1 provos 263: if (authenticated) {
264: if (!(ent->flags & MON_AUTHDECIDE))
265: fatal("%s: unexpected authentication from %d",
1.14 markus 266: __func__, ent->type);
1.1 provos 267: if (authctxt->pw->pw_uid == 0 &&
268: !auth_root_allowed(auth_method))
269: authenticated = 0;
270: }
1.77 dtucker 271: if (ent->flags & (MON_AUTHDECIDE|MON_ALOG)) {
1.119 djm 272: auth_log(authctxt, authenticated, partial,
1.125 djm 273: auth_method, auth_submethod);
1.150 djm 274: if (!partial && !authenticated)
1.1 provos 275: authctxt->failures++;
276: }
277: }
278:
279: if (!authctxt->valid)
1.14 markus 280: fatal("%s: authenticated invalid user", __func__);
1.77 dtucker 281: if (strcmp(auth_method, "unknown") == 0)
282: fatal("%s: authentication method name unknown", __func__);
1.1 provos 283:
284: debug("%s: %s has been authenticated by privileged process",
1.14 markus 285: __func__, authctxt->user);
1.1 provos 286:
1.11 mouring 287: mm_get_keystate(pmonitor);
1.120 markus 288:
289: /* Drain any buffered messages from the child */
290: while (pmonitor->m_log_recvfd != -1 && monitor_read_log(pmonitor) == 0)
291: ;
1.114 djm 292:
293: close(pmonitor->m_sendfd);
294: close(pmonitor->m_log_recvfd);
295: pmonitor->m_sendfd = pmonitor->m_log_recvfd = -1;
1.1 provos 296: }
297:
1.40 markus 298: static void
299: monitor_set_child_handler(pid_t pid)
300: {
301: monitor_child_pid = pid;
302: }
303:
304: static void
1.59 avsm 305: monitor_child_handler(int sig)
1.40 markus 306: {
1.59 avsm 307: kill(monitor_child_pid, sig);
1.40 markus 308: }
309:
1.1 provos 310: void
1.11 mouring 311: monitor_child_postauth(struct monitor *pmonitor)
1.1 provos 312: {
1.114 djm 313: close(pmonitor->m_recvfd);
314: pmonitor->m_recvfd = -1;
315:
1.40 markus 316: monitor_set_child_handler(pmonitor->m_pid);
317: signal(SIGHUP, &monitor_child_handler);
318: signal(SIGTERM, &monitor_child_handler);
1.91 djm 319: signal(SIGINT, &monitor_child_handler);
1.40 markus 320:
1.162 markus 321: mon_dispatch = mon_dispatch_postauth20;
322:
323: /* Permit requests for moduli and signatures */
324: monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
325: monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
326: monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1);
1.1 provos 327:
328: if (!no_pty_flag) {
329: monitor_permit(mon_dispatch, MONITOR_REQ_PTY, 1);
330: monitor_permit(mon_dispatch, MONITOR_REQ_PTYCLEANUP, 1);
331: }
332:
333: for (;;)
1.11 mouring 334: monitor_read(pmonitor, mon_dispatch, NULL);
1.1 provos 335: }
336:
1.114 djm 337: static int
338: monitor_read_log(struct monitor *pmonitor)
339: {
340: Buffer logmsg;
341: u_int len, level;
342: char *msg;
343:
344: buffer_init(&logmsg);
345:
346: /* Read length */
347: buffer_append_space(&logmsg, 4);
348: if (atomicio(read, pmonitor->m_log_recvfd,
349: buffer_ptr(&logmsg), buffer_len(&logmsg)) != buffer_len(&logmsg)) {
350: if (errno == EPIPE) {
1.116 djm 351: buffer_free(&logmsg);
1.114 djm 352: debug("%s: child log fd closed", __func__);
353: close(pmonitor->m_log_recvfd);
354: pmonitor->m_log_recvfd = -1;
355: return -1;
356: }
357: fatal("%s: log fd read: %s", __func__, strerror(errno));
358: }
359: len = buffer_get_int(&logmsg);
360: if (len <= 4 || len > 8192)
361: fatal("%s: invalid log message length %u", __func__, len);
362:
363: /* Read severity, message */
364: buffer_clear(&logmsg);
365: buffer_append_space(&logmsg, len);
366: if (atomicio(read, pmonitor->m_log_recvfd,
367: buffer_ptr(&logmsg), buffer_len(&logmsg)) != buffer_len(&logmsg))
368: fatal("%s: log fd read: %s", __func__, strerror(errno));
369:
370: /* Log it */
371: level = buffer_get_int(&logmsg);
372: msg = buffer_get_string(&logmsg, NULL);
373: if (log_level_name(level) == NULL)
374: fatal("%s: invalid log level %u (corrupted message?)",
375: __func__, level);
376: do_log2(level, "%s [preauth]", msg);
377:
378: buffer_free(&logmsg);
1.124 djm 379: free(msg);
1.114 djm 380:
381: return 0;
382: }
383:
1.1 provos 384: int
1.11 mouring 385: monitor_read(struct monitor *pmonitor, struct mon_table *ent,
1.1 provos 386: struct mon_table **pent)
387: {
388: Buffer m;
389: int ret;
390: u_char type;
1.114 djm 391: struct pollfd pfd[2];
392:
393: for (;;) {
1.130 tedu 394: memset(&pfd, 0, sizeof(pfd));
1.114 djm 395: pfd[0].fd = pmonitor->m_sendfd;
396: pfd[0].events = POLLIN;
397: pfd[1].fd = pmonitor->m_log_recvfd;
398: pfd[1].events = pfd[1].fd == -1 ? 0 : POLLIN;
1.115 djm 399: if (poll(pfd, pfd[1].fd == -1 ? 1 : 2, -1) == -1) {
400: if (errno == EINTR || errno == EAGAIN)
401: continue;
1.114 djm 402: fatal("%s: poll: %s", __func__, strerror(errno));
1.115 djm 403: }
1.114 djm 404: if (pfd[1].revents) {
405: /*
406: * Drain all log messages before processing next
407: * monitor request.
408: */
409: monitor_read_log(pmonitor);
410: continue;
411: }
412: if (pfd[0].revents)
413: break; /* Continues below */
414: }
1.1 provos 415:
416: buffer_init(&m);
417:
1.11 mouring 418: mm_request_receive(pmonitor->m_sendfd, &m);
1.1 provos 419: type = buffer_get_char(&m);
420:
1.14 markus 421: debug3("%s: checking request %d", __func__, type);
1.1 provos 422:
423: while (ent->f != NULL) {
424: if (ent->type == type)
425: break;
426: ent++;
427: }
428:
429: if (ent->f != NULL) {
430: if (!(ent->flags & MON_PERMIT))
1.14 markus 431: fatal("%s: unpermitted request %d", __func__,
1.1 provos 432: type);
1.11 mouring 433: ret = (*ent->f)(pmonitor->m_sendfd, &m);
1.1 provos 434: buffer_free(&m);
435:
436: /* The child may use this request only once, disable it */
437: if (ent->flags & MON_ONCE) {
1.14 markus 438: debug2("%s: %d used once, disabling now", __func__,
1.1 provos 439: type);
440: ent->flags &= ~MON_PERMIT;
441: }
442:
443: if (pent != NULL)
444: *pent = ent;
1.3 markus 445:
1.1 provos 446: return ret;
447: }
448:
1.14 markus 449: fatal("%s: unsupported request: %d", __func__, type);
1.1 provos 450:
451: /* NOTREACHED */
452: return (-1);
453: }
454:
455: /* allowed key state */
456: static int
457: monitor_allowed_key(u_char *blob, u_int bloblen)
458: {
459: /* make sure key is allowed */
460: if (key_blob == NULL || key_bloblen != bloblen ||
1.108 djm 461: timingsafe_bcmp(key_blob, blob, key_bloblen))
1.1 provos 462: return (0);
463: return (1);
464: }
465:
466: static void
467: monitor_reset_key_state(void)
468: {
469: /* reset state */
1.124 djm 470: free(key_blob);
471: free(hostbased_cuser);
472: free(hostbased_chost);
1.1 provos 473: key_blob = NULL;
474: key_bloblen = 0;
475: key_blobtype = MM_NOKEY;
476: hostbased_cuser = NULL;
477: hostbased_chost = NULL;
478: }
479:
1.132 markus 480: #ifdef WITH_OPENSSL
1.1 provos 481: int
1.59 avsm 482: mm_answer_moduli(int sock, Buffer *m)
1.1 provos 483: {
484: DH *dh;
485: int min, want, max;
486:
487: min = buffer_get_int(m);
488: want = buffer_get_int(m);
489: max = buffer_get_int(m);
490:
491: debug3("%s: got parameters: %d %d %d",
1.14 markus 492: __func__, min, want, max);
1.1 provos 493: /* We need to check here, too, in case the child got corrupted */
494: if (max < min || want < min || max < want)
495: fatal("%s: bad parameters: %d %d %d",
1.14 markus 496: __func__, min, want, max);
1.1 provos 497:
498: buffer_clear(m);
499:
500: dh = choose_dh(min, want, max);
501: if (dh == NULL) {
502: buffer_put_char(m, 0);
503: return (0);
504: } else {
505: /* Send first bignum */
506: buffer_put_char(m, 1);
507: buffer_put_bignum2(m, dh->p);
508: buffer_put_bignum2(m, dh->g);
1.3 markus 509:
1.1 provos 510: DH_free(dh);
511: }
1.59 avsm 512: mm_request_send(sock, MONITOR_ANS_MODULI, m);
1.1 provos 513: return (0);
514: }
1.132 markus 515: #endif
1.1 provos 516:
517: int
1.59 avsm 518: mm_answer_sign(int sock, Buffer *m)
1.1 provos 519: {
1.144 djm 520: struct ssh *ssh = active_state; /* XXX */
1.138 djm 521: extern int auth_sock; /* XXX move to state struct? */
522: struct sshkey *key;
1.157 djm 523: struct sshbuf *sigbuf = NULL;
524: u_char *p = NULL, *signature = NULL;
525: char *alg = NULL;
1.155 markus 526: size_t datlen, siglen, alglen;
1.159 djm 527: int r, is_proof = 0;
528: u_int keyid;
1.145 djm 529: const char proof_req[] = "hostkeys-prove-00@openssh.com";
1.3 markus 530:
1.14 markus 531: debug3("%s", __func__);
1.1 provos 532:
1.138 djm 533: if ((r = sshbuf_get_u32(m, &keyid)) != 0 ||
1.155 markus 534: (r = sshbuf_get_string(m, &p, &datlen)) != 0 ||
535: (r = sshbuf_get_cstring(m, &alg, &alglen)) != 0)
1.138 djm 536: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.159 djm 537: if (keyid > INT_MAX)
538: fatal("%s: invalid key ID", __func__);
1.1 provos 539:
1.69 djm 540: /*
1.110 djm 541: * Supported KEX types use SHA1 (20 bytes), SHA256 (32 bytes),
542: * SHA384 (48 bytes) and SHA512 (64 bytes).
1.144 djm 543: *
544: * Otherwise, verify the signature request is for a hostkey
545: * proof.
546: *
547: * XXX perform similar check for KEX signature requests too?
548: * it's not trivial, since what is signed is the hash, rather
549: * than the full kex structure...
1.69 djm 550: */
1.144 djm 551: if (datlen != 20 && datlen != 32 && datlen != 48 && datlen != 64) {
552: /*
553: * Construct expected hostkey proof and compare it to what
554: * the client sent us.
555: */
556: if (session_id2_len == 0) /* hostkeys is never first */
557: fatal("%s: bad data length: %zu", __func__, datlen);
558: if ((key = get_hostkey_public_by_index(keyid, ssh)) == NULL)
559: fatal("%s: no hostkey for index %d", __func__, keyid);
560: if ((sigbuf = sshbuf_new()) == NULL)
561: fatal("%s: sshbuf_new", __func__);
1.145 djm 562: if ((r = sshbuf_put_cstring(sigbuf, proof_req)) != 0 ||
563: (r = sshbuf_put_string(sigbuf, session_id2,
1.152 jsg 564: session_id2_len)) != 0 ||
1.144 djm 565: (r = sshkey_puts(key, sigbuf)) != 0)
566: fatal("%s: couldn't prepare private key "
567: "proof buffer: %s", __func__, ssh_err(r));
568: if (datlen != sshbuf_len(sigbuf) ||
569: memcmp(p, sshbuf_ptr(sigbuf), sshbuf_len(sigbuf)) != 0)
570: fatal("%s: bad data length: %zu, hostkey proof len %zu",
571: __func__, datlen, sshbuf_len(sigbuf));
572: sshbuf_free(sigbuf);
573: is_proof = 1;
574: }
1.1 provos 575:
1.13 markus 576: /* save session id, it will be passed on the first call */
577: if (session_id2_len == 0) {
578: session_id2_len = datlen;
579: session_id2 = xmalloc(session_id2_len);
580: memcpy(session_id2, p, session_id2_len);
581: }
582:
1.127 markus 583: if ((key = get_hostkey_by_index(keyid)) != NULL) {
1.155 markus 584: if ((r = sshkey_sign(key, &signature, &siglen, p, datlen, alg,
1.138 djm 585: datafellows)) != 0)
586: fatal("%s: sshkey_sign failed: %s",
587: __func__, ssh_err(r));
1.144 djm 588: } else if ((key = get_hostkey_public_by_index(keyid, ssh)) != NULL &&
1.138 djm 589: auth_sock > 0) {
590: if ((r = ssh_agent_sign(auth_sock, key, &signature, &siglen,
1.155 markus 591: p, datlen, alg, datafellows)) != 0) {
1.138 djm 592: fatal("%s: ssh_agent_sign failed: %s",
593: __func__, ssh_err(r));
594: }
1.127 markus 595: } else
1.14 markus 596: fatal("%s: no hostkey from index %d", __func__, keyid);
1.1 provos 597:
1.144 djm 598: debug3("%s: %s signature %p(%zu)", __func__,
599: is_proof ? "KEX" : "hostkey proof", signature, siglen);
1.1 provos 600:
1.138 djm 601: sshbuf_reset(m);
602: if ((r = sshbuf_put_string(m, signature, siglen)) != 0)
603: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.1 provos 604:
1.157 djm 605: free(alg);
1.124 djm 606: free(p);
607: free(signature);
1.1 provos 608:
1.59 avsm 609: mm_request_send(sock, MONITOR_ANS_SIGN, m);
1.1 provos 610:
611: /* Turn on permissions for getpwnam */
612: monitor_permit(mon_dispatch, MONITOR_REQ_PWNAM, 1);
613:
614: return (0);
615: }
616:
617: /* Retrieves the password entry and also checks if the user is permitted */
618:
619: int
1.59 avsm 620: mm_answer_pwnamallow(int sock, Buffer *m)
1.1 provos 621: {
1.60 dtucker 622: char *username;
1.1 provos 623: struct passwd *pwent;
624: int allowed = 0;
1.113 djm 625: u_int i;
1.3 markus 626:
1.14 markus 627: debug3("%s", __func__);
1.1 provos 628:
629: if (authctxt->attempt++ != 0)
1.14 markus 630: fatal("%s: multiple attempts for getpwnam", __func__);
1.1 provos 631:
1.60 dtucker 632: username = buffer_get_string(m, NULL);
1.1 provos 633:
1.60 dtucker 634: pwent = getpwnamallow(username);
1.1 provos 635:
1.60 dtucker 636: authctxt->user = xstrdup(username);
637: setproctitle("%s [priv]", pwent ? username : "unknown");
1.124 djm 638: free(username);
1.1 provos 639:
640: buffer_clear(m);
641:
642: if (pwent == NULL) {
643: buffer_put_char(m, 0);
1.53 djm 644: authctxt->pw = fakepw();
1.1 provos 645: goto out;
646: }
647:
648: allowed = 1;
1.4 markus 649: authctxt->pw = pwent;
1.1 provos 650: authctxt->valid = 1;
651:
652: buffer_put_char(m, 1);
653: buffer_put_string(m, pwent, sizeof(struct passwd));
654: buffer_put_cstring(m, pwent->pw_name);
655: buffer_put_cstring(m, "*");
656: buffer_put_cstring(m, pwent->pw_gecos);
657: buffer_put_cstring(m, pwent->pw_class);
658: buffer_put_cstring(m, pwent->pw_dir);
659: buffer_put_cstring(m, pwent->pw_shell);
1.94 dtucker 660:
661: out:
1.90 dtucker 662: buffer_put_string(m, &options, sizeof(options));
1.112 djm 663:
664: #define M_CP_STROPT(x) do { \
665: if (options.x != NULL) \
666: buffer_put_cstring(m, options.x); \
667: } while (0)
1.113 djm 668: #define M_CP_STRARRAYOPT(x, nx) do { \
669: for (i = 0; i < options.nx; i++) \
670: buffer_put_cstring(m, options.x[i]); \
671: } while (0)
1.112 djm 672: /* See comment in servconf.h */
673: COPY_MATCH_STRING_OPTS();
674: #undef M_CP_STROPT
1.113 djm 675: #undef M_CP_STRARRAYOPT
1.118 djm 676:
677: /* Create valid auth method lists */
1.162 markus 678: if (auth2_setup_methods_lists(authctxt) != 0) {
1.118 djm 679: /*
680: * The monitor will continue long enough to let the child
681: * run to it's packet_disconnect(), but it must not allow any
682: * authentication to succeed.
683: */
684: debug("%s: no valid authentication method lists", __func__);
685: }
686:
1.14 markus 687: debug3("%s: sending MONITOR_ANS_PWNAM: %d", __func__, allowed);
1.59 avsm 688: mm_request_send(sock, MONITOR_ANS_PWNAM, m);
1.1 provos 689:
1.162 markus 690: /* Allow service/style information on the auth context */
691: monitor_permit(mon_dispatch, MONITOR_REQ_AUTHSERV, 1);
692: monitor_permit(mon_dispatch, MONITOR_REQ_AUTH2_READ_BANNER, 1);
1.10 djm 693:
694: return (0);
695: }
696:
1.59 avsm 697: int mm_answer_auth2_read_banner(int sock, Buffer *m)
1.10 djm 698: {
699: char *banner;
700:
701: buffer_clear(m);
702: banner = auth2_read_banner();
703: buffer_put_cstring(m, banner != NULL ? banner : "");
1.59 avsm 704: mm_request_send(sock, MONITOR_ANS_AUTH2_READ_BANNER, m);
1.124 djm 705: free(banner);
1.1 provos 706:
707: return (0);
708: }
709:
710: int
1.59 avsm 711: mm_answer_authserv(int sock, Buffer *m)
1.1 provos 712: {
713: monitor_permit_authentications(1);
714:
715: authctxt->service = buffer_get_string(m, NULL);
716: authctxt->style = buffer_get_string(m, NULL);
1.6 stevesk 717: debug3("%s: service=%s, style=%s",
1.14 markus 718: __func__, authctxt->service, authctxt->style);
1.6 stevesk 719:
1.1 provos 720: if (strlen(authctxt->style) == 0) {
1.124 djm 721: free(authctxt->style);
1.1 provos 722: authctxt->style = NULL;
723: }
724:
725: return (0);
726: }
727:
728: int
1.59 avsm 729: mm_answer_authpassword(int sock, Buffer *m)
1.1 provos 730: {
731: static int call_count;
732: char *passwd;
1.22 stevesk 733: int authenticated;
734: u_int plen;
1.1 provos 735:
1.164 djm 736: if (!options.password_authentication)
737: fatal("%s: password authentication not enabled", __func__);
1.1 provos 738: passwd = buffer_get_string(m, &plen);
739: /* Only authenticate if the context is valid */
1.12 markus 740: authenticated = options.password_authentication &&
1.48 markus 741: auth_password(authctxt, passwd);
1.131 djm 742: explicit_bzero(passwd, strlen(passwd));
1.124 djm 743: free(passwd);
1.1 provos 744:
745: buffer_clear(m);
746: buffer_put_int(m, authenticated);
747:
1.14 markus 748: debug3("%s: sending result %d", __func__, authenticated);
1.59 avsm 749: mm_request_send(sock, MONITOR_ANS_AUTHPASSWORD, m);
1.1 provos 750:
751: call_count++;
752: if (plen == 0 && call_count == 1)
753: auth_method = "none";
754: else
755: auth_method = "password";
756:
757: /* Causes monitor loop to terminate if authenticated */
758: return (authenticated);
759: }
760:
761: int
1.59 avsm 762: mm_answer_bsdauthquery(int sock, Buffer *m)
1.1 provos 763: {
764: char *name, *infotxt;
765: u_int numprompts;
766: u_int *echo_on;
767: char **prompts;
1.31 markus 768: u_int success;
1.1 provos 769:
1.164 djm 770: if (!options.kbd_interactive_authentication)
771: fatal("%s: kbd-int authentication not enabled", __func__);
1.31 markus 772: success = bsdauth_query(authctxt, &name, &infotxt, &numprompts,
773: &prompts, &echo_on) < 0 ? 0 : 1;
1.1 provos 774:
775: buffer_clear(m);
1.31 markus 776: buffer_put_int(m, success);
777: if (success)
1.1 provos 778: buffer_put_cstring(m, prompts[0]);
779:
1.31 markus 780: debug3("%s: sending challenge success: %u", __func__, success);
1.59 avsm 781: mm_request_send(sock, MONITOR_ANS_BSDAUTHQUERY, m);
1.1 provos 782:
1.31 markus 783: if (success) {
1.124 djm 784: free(name);
785: free(infotxt);
786: free(prompts);
787: free(echo_on);
1.1 provos 788: }
789:
790: return (0);
791: }
792:
793: int
1.59 avsm 794: mm_answer_bsdauthrespond(int sock, Buffer *m)
1.1 provos 795: {
796: char *response;
797: int authok;
798:
1.164 djm 799: if (!options.kbd_interactive_authentication)
800: fatal("%s: kbd-int authentication not enabled", __func__);
1.154 mmcc 801: if (authctxt->as == NULL)
1.14 markus 802: fatal("%s: no bsd auth session", __func__);
1.1 provos 803:
804: response = buffer_get_string(m, NULL);
1.12 markus 805: authok = options.challenge_response_authentication &&
806: auth_userresponse(authctxt->as, response, 0);
1.1 provos 807: authctxt->as = NULL;
1.14 markus 808: debug3("%s: <%s> = <%d>", __func__, response, authok);
1.124 djm 809: free(response);
1.1 provos 810:
811: buffer_clear(m);
812: buffer_put_int(m, authok);
813:
1.14 markus 814: debug3("%s: sending authenticated: %d", __func__, authok);
1.59 avsm 815: mm_request_send(sock, MONITOR_ANS_BSDAUTHRESPOND, m);
1.1 provos 816:
1.162 markus 817: auth_method = "keyboard-interactive";
818: auth_submethod = "bsdauth";
1.1 provos 819:
820: return (authok != 0);
821: }
822:
823: int
1.59 avsm 824: mm_answer_keyallowed(int sock, Buffer *m)
1.1 provos 825: {
826: Key *key;
1.26 markus 827: char *cuser, *chost;
828: u_char *blob;
1.148 djm 829: u_int bloblen, pubkey_auth_attempt;
1.1 provos 830: enum mm_keytype type = 0;
831: int allowed = 0;
832:
1.14 markus 833: debug3("%s entering", __func__);
1.3 markus 834:
1.1 provos 835: type = buffer_get_int(m);
836: cuser = buffer_get_string(m, NULL);
837: chost = buffer_get_string(m, NULL);
838: blob = buffer_get_string(m, &bloblen);
1.148 djm 839: pubkey_auth_attempt = buffer_get_int(m);
1.1 provos 840:
841: key = key_from_blob(blob, bloblen);
842:
1.14 markus 843: debug3("%s: key_from_blob: %p", __func__, key);
1.1 provos 844:
1.51 djm 845: if (key != NULL && authctxt->valid) {
1.137 djm 846: /* These should not make it past the privsep child */
847: if (key_type_plain(key->type) == KEY_RSA &&
848: (datafellows & SSH_BUG_RSASIGMD5) != 0)
849: fatal("%s: passed a SSH_BUG_RSASIGMD5 key", __func__);
850:
1.63 deraadt 851: switch (type) {
1.1 provos 852: case MM_USERKEY:
1.12 markus 853: allowed = options.pubkey_authentication &&
1.136 djm 854: !auth2_userkey_already_used(authctxt, key) &&
1.137 djm 855: match_pattern_list(sshkey_ssh_name(key),
1.149 djm 856: options.pubkey_key_types, 0) == 1 &&
1.148 djm 857: user_key_allowed(authctxt->pw, key,
858: pubkey_auth_attempt);
1.126 djm 859: pubkey_auth_info(authctxt, key, NULL);
1.77 dtucker 860: auth_method = "publickey";
1.148 djm 861: if (options.pubkey_authentication &&
862: (!pubkey_auth_attempt || allowed != 1))
1.97 dtucker 863: auth_clear_options();
1.1 provos 864: break;
865: case MM_HOSTKEY:
1.12 markus 866: allowed = options.hostbased_authentication &&
1.137 djm 867: match_pattern_list(sshkey_ssh_name(key),
1.149 djm 868: options.hostbased_key_types, 0) == 1 &&
1.12 markus 869: hostbased_key_allowed(authctxt->pw,
1.1 provos 870: cuser, chost, key);
1.126 djm 871: pubkey_auth_info(authctxt, key,
872: "client user \"%.100s\", client host \"%.100s\"",
873: cuser, chost);
1.77 dtucker 874: auth_method = "hostbased";
1.1 provos 875: break;
876: default:
1.14 markus 877: fatal("%s: unknown key type %d", __func__, type);
1.1 provos 878: break;
879: }
1.33 markus 880: }
1.161 djm 881:
882: debug3("%s: key %p is %s",
883: __func__, key, allowed ? "allowed" : "not allowed");
884:
1.33 markus 885: if (key != NULL)
1.1 provos 886: key_free(key);
887:
888: /* clear temporarily storage (used by verify) */
889: monitor_reset_key_state();
890:
891: if (allowed) {
892: /* Save temporarily for comparison in verify */
893: key_blob = blob;
894: key_bloblen = bloblen;
895: key_blobtype = type;
896: hostbased_cuser = cuser;
897: hostbased_chost = chost;
1.72 djm 898: } else {
1.77 dtucker 899: /* Log failed attempt */
1.125 djm 900: auth_log(authctxt, 0, 0, auth_method, NULL);
1.124 djm 901: free(blob);
902: free(cuser);
903: free(chost);
1.1 provos 904: }
905:
906: buffer_clear(m);
907: buffer_put_int(m, allowed);
1.32 markus 908: buffer_put_int(m, forced_command != NULL);
1.1 provos 909:
1.59 avsm 910: mm_request_send(sock, MONITOR_ANS_KEYALLOWED, m);
1.1 provos 911:
912: return (0);
913: }
914:
915: static int
916: monitor_valid_userblob(u_char *data, u_int datalen)
917: {
918: Buffer b;
1.159 djm 919: u_char *p;
920: char *userstyle, *cp;
1.1 provos 921: u_int len;
922: int fail = 0;
923:
924: buffer_init(&b);
925: buffer_append(&b, data, datalen);
1.3 markus 926:
1.1 provos 927: if (datafellows & SSH_OLD_SESSIONID) {
1.13 markus 928: p = buffer_ptr(&b);
929: len = buffer_len(&b);
930: if ((session_id2 == NULL) ||
931: (len < session_id2_len) ||
1.108 djm 932: (timingsafe_bcmp(p, session_id2, session_id2_len) != 0))
1.13 markus 933: fail++;
1.1 provos 934: buffer_consume(&b, session_id2_len);
935: } else {
1.13 markus 936: p = buffer_get_string(&b, &len);
937: if ((session_id2 == NULL) ||
938: (len != session_id2_len) ||
1.108 djm 939: (timingsafe_bcmp(p, session_id2, session_id2_len) != 0))
1.1 provos 940: fail++;
1.124 djm 941: free(p);
1.1 provos 942: }
943: if (buffer_get_char(&b) != SSH2_MSG_USERAUTH_REQUEST)
944: fail++;
1.159 djm 945: cp = buffer_get_cstring(&b, NULL);
1.121 djm 946: xasprintf(&userstyle, "%s%s%s", authctxt->user,
947: authctxt->style ? ":" : "",
948: authctxt->style ? authctxt->style : "");
1.159 djm 949: if (strcmp(userstyle, cp) != 0) {
950: logit("wrong user name passed to monitor: "
951: "expected %s != %.100s", userstyle, cp);
1.1 provos 952: fail++;
953: }
1.124 djm 954: free(userstyle);
1.159 djm 955: free(cp);
1.1 provos 956: buffer_skip_string(&b);
957: if (datafellows & SSH_BUG_PKAUTH) {
958: if (!buffer_get_char(&b))
959: fail++;
960: } else {
1.159 djm 961: cp = buffer_get_cstring(&b, NULL);
962: if (strcmp("publickey", cp) != 0)
1.1 provos 963: fail++;
1.159 djm 964: free(cp);
1.1 provos 965: if (!buffer_get_char(&b))
966: fail++;
967: buffer_skip_string(&b);
968: }
969: buffer_skip_string(&b);
970: if (buffer_len(&b) != 0)
971: fail++;
972: buffer_free(&b);
973: return (fail == 0);
974: }
975:
976: static int
1.26 markus 977: monitor_valid_hostbasedblob(u_char *data, u_int datalen, char *cuser,
978: char *chost)
1.1 provos 979: {
980: Buffer b;
1.121 djm 981: char *p, *userstyle;
1.1 provos 982: u_int len;
983: int fail = 0;
984:
985: buffer_init(&b);
986: buffer_append(&b, data, datalen);
1.3 markus 987:
1.13 markus 988: p = buffer_get_string(&b, &len);
989: if ((session_id2 == NULL) ||
990: (len != session_id2_len) ||
1.108 djm 991: (timingsafe_bcmp(p, session_id2, session_id2_len) != 0))
1.1 provos 992: fail++;
1.124 djm 993: free(p);
1.13 markus 994:
1.1 provos 995: if (buffer_get_char(&b) != SSH2_MSG_USERAUTH_REQUEST)
996: fail++;
1.121 djm 997: p = buffer_get_cstring(&b, NULL);
998: xasprintf(&userstyle, "%s%s%s", authctxt->user,
999: authctxt->style ? ":" : "",
1000: authctxt->style ? authctxt->style : "");
1001: if (strcmp(userstyle, p) != 0) {
1.38 itojun 1002: logit("wrong user name passed to monitor: expected %s != %.100s",
1.121 djm 1003: userstyle, p);
1.1 provos 1004: fail++;
1005: }
1.121 djm 1006: free(userstyle);
1.124 djm 1007: free(p);
1.1 provos 1008: buffer_skip_string(&b); /* service */
1.121 djm 1009: p = buffer_get_cstring(&b, NULL);
1.1 provos 1010: if (strcmp(p, "hostbased") != 0)
1011: fail++;
1.124 djm 1012: free(p);
1.1 provos 1013: buffer_skip_string(&b); /* pkalg */
1014: buffer_skip_string(&b); /* pkblob */
1015:
1016: /* verify client host, strip trailing dot if necessary */
1017: p = buffer_get_string(&b, NULL);
1018: if (((len = strlen(p)) > 0) && p[len - 1] == '.')
1019: p[len - 1] = '\0';
1020: if (strcmp(p, chost) != 0)
1021: fail++;
1.124 djm 1022: free(p);
1.1 provos 1023:
1024: /* verify client user */
1025: p = buffer_get_string(&b, NULL);
1026: if (strcmp(p, cuser) != 0)
1027: fail++;
1.124 djm 1028: free(p);
1.1 provos 1029:
1030: if (buffer_len(&b) != 0)
1031: fail++;
1032: buffer_free(&b);
1033: return (fail == 0);
1034: }
1035:
1036: int
1.59 avsm 1037: mm_answer_keyverify(int sock, Buffer *m)
1.1 provos 1038: {
1039: Key *key;
1040: u_char *signature, *data, *blob;
1041: u_int signaturelen, datalen, bloblen;
1042: int verified = 0;
1043: int valid_data = 0;
1044:
1045: blob = buffer_get_string(m, &bloblen);
1046: signature = buffer_get_string(m, &signaturelen);
1047: data = buffer_get_string(m, &datalen);
1048:
1049: if (hostbased_cuser == NULL || hostbased_chost == NULL ||
1.8 mouring 1050: !monitor_allowed_key(blob, bloblen))
1.14 markus 1051: fatal("%s: bad key, not previously allowed", __func__);
1.1 provos 1052:
1053: key = key_from_blob(blob, bloblen);
1054: if (key == NULL)
1.14 markus 1055: fatal("%s: bad public key blob", __func__);
1.1 provos 1056:
1057: switch (key_blobtype) {
1058: case MM_USERKEY:
1059: valid_data = monitor_valid_userblob(data, datalen);
1060: break;
1061: case MM_HOSTKEY:
1062: valid_data = monitor_valid_hostbasedblob(data, datalen,
1063: hostbased_cuser, hostbased_chost);
1064: break;
1065: default:
1066: valid_data = 0;
1067: break;
1068: }
1069: if (!valid_data)
1.14 markus 1070: fatal("%s: bad signature data blob", __func__);
1.1 provos 1071:
1072: verified = key_verify(key, signature, signaturelen, data, datalen);
1073: debug3("%s: key %p signature %s",
1.89 markus 1074: __func__, key, (verified == 1) ? "verified" : "unverified");
1.1 provos 1075:
1.136 djm 1076: /* If auth was successful then record key to ensure it isn't reused */
1.153 djm 1077: if (verified == 1 && key_blobtype == MM_USERKEY)
1.136 djm 1078: auth2_record_userkey(authctxt, key);
1079: else
1080: key_free(key);
1081:
1.124 djm 1082: free(blob);
1083: free(signature);
1084: free(data);
1.1 provos 1085:
1.17 stevesk 1086: auth_method = key_blobtype == MM_USERKEY ? "publickey" : "hostbased";
1087:
1.1 provos 1088: monitor_reset_key_state();
1.3 markus 1089:
1.1 provos 1090: buffer_clear(m);
1091: buffer_put_int(m, verified);
1.59 avsm 1092: mm_request_send(sock, MONITOR_ANS_KEYVERIFY, m);
1.1 provos 1093:
1.89 markus 1094: return (verified == 1);
1.1 provos 1095: }
1096:
1.2 markus 1097: static void
1.1 provos 1098: mm_record_login(Session *s, struct passwd *pw)
1099: {
1.158 djm 1100: struct ssh *ssh = active_state; /* XXX */
1.1 provos 1101: socklen_t fromlen;
1102: struct sockaddr_storage from;
1103:
1104: /*
1105: * Get IP address of client. If the connection is not a socket, let
1106: * the address be 0.0.0.0.
1107: */
1108: memset(&from, 0, sizeof(from));
1.24 stevesk 1109: fromlen = sizeof(from);
1.1 provos 1110: if (packet_connection_is_on_socket()) {
1111: if (getpeername(packet_get_connection_in(),
1.74 deraadt 1112: (struct sockaddr *)&from, &fromlen) < 0) {
1.1 provos 1113: debug("getpeername: %.100s", strerror(errno));
1.50 markus 1114: cleanup_exit(255);
1.1 provos 1115: }
1116: }
1117: /* Record that there was a login on that tty from the remote host. */
1118: record_login(s->pid, s->tty, pw->pw_name, pw->pw_uid,
1.158 djm 1119: session_get_remote_name_or_ip(ssh, utmp_len, options.use_dns),
1.24 stevesk 1120: (struct sockaddr *)&from, fromlen);
1.1 provos 1121: }
1122:
1123: static void
1124: mm_session_close(Session *s)
1125: {
1.41 djm 1126: debug3("%s: session %d pid %ld", __func__, s->self, (long)s->pid);
1.1 provos 1127: if (s->ttyfd != -1) {
1.86 stevesk 1128: debug3("%s: tty %s ptyfd %d", __func__, s->tty, s->ptyfd);
1.1 provos 1129: session_pty_cleanup2(s);
1130: }
1.96 djm 1131: session_unused(s->self);
1.1 provos 1132: }
1133:
1134: int
1.59 avsm 1135: mm_answer_pty(int sock, Buffer *m)
1.1 provos 1136: {
1.11 mouring 1137: extern struct monitor *pmonitor;
1.1 provos 1138: Session *s;
1139: int res, fd0;
1140:
1.14 markus 1141: debug3("%s entering", __func__);
1.1 provos 1142:
1143: buffer_clear(m);
1144: s = session_new();
1145: if (s == NULL)
1146: goto error;
1147: s->authctxt = authctxt;
1148: s->pw = authctxt->pw;
1.11 mouring 1149: s->pid = pmonitor->m_pid;
1.1 provos 1150: res = pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty));
1151: if (res == 0)
1152: goto error;
1153: pty_setowner(authctxt->pw, s->tty);
1154:
1155: buffer_put_int(m, 1);
1156: buffer_put_cstring(m, s->tty);
1157:
1158: /* We need to trick ttyslot */
1159: if (dup2(s->ttyfd, 0) == -1)
1.14 markus 1160: fatal("%s: dup2", __func__);
1.1 provos 1161:
1162: mm_record_login(s, authctxt->pw);
1163:
1164: /* Now we can close the file descriptor again */
1165: close(0);
1.61 dtucker 1166:
1167: /* send messages generated by record_login */
1168: buffer_put_string(m, buffer_ptr(&loginmsg), buffer_len(&loginmsg));
1169: buffer_clear(&loginmsg);
1170:
1171: mm_request_send(sock, MONITOR_ANS_PTY, m);
1172:
1.92 djm 1173: if (mm_send_fd(sock, s->ptyfd) == -1 ||
1174: mm_send_fd(sock, s->ttyfd) == -1)
1175: fatal("%s: send fds failed", __func__);
1.1 provos 1176:
1177: /* make sure nothing uses fd 0 */
1178: if ((fd0 = open(_PATH_DEVNULL, O_RDONLY)) < 0)
1.14 markus 1179: fatal("%s: open(/dev/null): %s", __func__, strerror(errno));
1.1 provos 1180: if (fd0 != 0)
1.14 markus 1181: error("%s: fd0 %d != 0", __func__, fd0);
1.1 provos 1182:
1183: /* slave is not needed */
1184: close(s->ttyfd);
1185: s->ttyfd = s->ptyfd;
1186: /* no need to dup() because nobody closes ptyfd */
1187: s->ptymaster = s->ptyfd;
1188:
1.86 stevesk 1189: debug3("%s: tty %s ptyfd %d", __func__, s->tty, s->ttyfd);
1.1 provos 1190:
1191: return (0);
1192:
1193: error:
1194: if (s != NULL)
1195: mm_session_close(s);
1196: buffer_put_int(m, 0);
1.59 avsm 1197: mm_request_send(sock, MONITOR_ANS_PTY, m);
1.1 provos 1198: return (0);
1199: }
1200:
1201: int
1.59 avsm 1202: mm_answer_pty_cleanup(int sock, Buffer *m)
1.1 provos 1203: {
1204: Session *s;
1205: char *tty;
1206:
1.14 markus 1207: debug3("%s entering", __func__);
1.1 provos 1208:
1209: tty = buffer_get_string(m, NULL);
1210: if ((s = session_by_tty(tty)) != NULL)
1211: mm_session_close(s);
1212: buffer_clear(m);
1.124 djm 1213: free(tty);
1.1 provos 1214: return (0);
1215: }
1216:
1217: int
1.59 avsm 1218: mm_answer_term(int sock, Buffer *req)
1.1 provos 1219: {
1.11 mouring 1220: extern struct monitor *pmonitor;
1.1 provos 1221: int res, status;
1222:
1.14 markus 1223: debug3("%s: tearing down sessions", __func__);
1.1 provos 1224:
1225: /* The child is terminating */
1226: session_destroy_all(&mm_session_close);
1227:
1.11 mouring 1228: while (waitpid(pmonitor->m_pid, &status, 0) == -1)
1.9 markus 1229: if (errno != EINTR)
1230: exit(1);
1.1 provos 1231:
1232: res = WIFEXITED(status) ? WEXITSTATUS(status) : 1;
1233:
1234: /* Terminate process */
1.57 deraadt 1235: exit(res);
1.1 provos 1236: }
1237:
1238: void
1.11 mouring 1239: monitor_apply_keystate(struct monitor *pmonitor)
1.1 provos 1240: {
1.139 markus 1241: struct ssh *ssh = active_state; /* XXX */
1242: struct kex *kex;
1243: int r;
1244:
1245: debug3("%s: packet_set_state", __func__);
1246: if ((r = ssh_packet_set_state(ssh, child_state)) != 0)
1247: fatal("%s: packet_set_state: %s", __func__, ssh_err(r));
1248: sshbuf_free(child_state);
1249: child_state = NULL;
1250:
1.154 mmcc 1251: if ((kex = ssh->kex) != NULL) {
1.139 markus 1252: /* XXX set callbacks */
1.147 djm 1253: #ifdef WITH_OPENSSL
1.139 markus 1254: kex->kex[KEX_DH_GRP1_SHA1] = kexdh_server;
1255: kex->kex[KEX_DH_GRP14_SHA1] = kexdh_server;
1.160 djm 1256: kex->kex[KEX_DH_GRP14_SHA256] = kexdh_server;
1257: kex->kex[KEX_DH_GRP16_SHA512] = kexdh_server;
1258: kex->kex[KEX_DH_GRP18_SHA512] = kexdh_server;
1.139 markus 1259: kex->kex[KEX_DH_GEX_SHA1] = kexgex_server;
1260: kex->kex[KEX_DH_GEX_SHA256] = kexgex_server;
1261: kex->kex[KEX_ECDH_SHA2] = kexecdh_server;
1.147 djm 1262: #endif
1.139 markus 1263: kex->kex[KEX_C25519_SHA256] = kexc25519_server;
1264: kex->load_host_public_key=&get_hostkey_public_by_type;
1265: kex->load_host_private_key=&get_hostkey_private_by_type;
1266: kex->host_key_index=&get_hostkey_index;
1267: kex->sign = sshd_hostkey_sign;
1268: }
1.1 provos 1269: }
1270:
1271: /* This function requries careful sanity checking */
1272:
1273: void
1.11 mouring 1274: mm_get_keystate(struct monitor *pmonitor)
1.1 provos 1275: {
1.14 markus 1276: debug3("%s: Waiting for new keys", __func__);
1.1 provos 1277:
1.139 markus 1278: if ((child_state = sshbuf_new()) == NULL)
1279: fatal("%s: sshbuf_new failed", __func__);
1280: mm_request_receive_expect(pmonitor->m_sendfd, MONITOR_REQ_KEYEXPORT,
1281: child_state);
1282: debug3("%s: GOT new keys", __func__);
1.1 provos 1283: }
1284:
1285:
1286: /* XXX */
1287:
1288: #define FD_CLOSEONEXEC(x) do { \
1.111 djm 1289: if (fcntl(x, F_SETFD, FD_CLOEXEC) == -1) \
1.1 provos 1290: fatal("fcntl(%d, F_SETFD)", x); \
1291: } while (0)
1292:
1.2 markus 1293: static void
1.114 djm 1294: monitor_openfds(struct monitor *mon, int do_logfds)
1.3 markus 1295: {
1.114 djm 1296: int pair[2];
1297:
1.1 provos 1298: if (socketpair(AF_UNIX, SOCK_STREAM, 0, pair) == -1)
1.114 djm 1299: fatal("%s: socketpair: %s", __func__, strerror(errno));
1.1 provos 1300: FD_CLOSEONEXEC(pair[0]);
1301: FD_CLOSEONEXEC(pair[1]);
1.114 djm 1302: mon->m_recvfd = pair[0];
1303: mon->m_sendfd = pair[1];
1304:
1305: if (do_logfds) {
1306: if (pipe(pair) == -1)
1307: fatal("%s: pipe: %s", __func__, strerror(errno));
1308: FD_CLOSEONEXEC(pair[0]);
1309: FD_CLOSEONEXEC(pair[1]);
1310: mon->m_log_recvfd = pair[0];
1311: mon->m_log_sendfd = pair[1];
1312: } else
1313: mon->m_log_recvfd = mon->m_log_sendfd = -1;
1.1 provos 1314: }
1315:
1316: #define MM_MEMSIZE 65536
1317:
1318: struct monitor *
1319: monitor_init(void)
1320: {
1321: struct monitor *mon;
1322:
1.75 djm 1323: mon = xcalloc(1, sizeof(*mon));
1.114 djm 1324: monitor_openfds(mon, 1);
1.1 provos 1325:
1326: return mon;
1327: }
1328:
1329: void
1330: monitor_reinit(struct monitor *mon)
1331: {
1.114 djm 1332: monitor_openfds(mon, 0);
1.1 provos 1333: }
1.46 markus 1334:
1335: #ifdef GSSAPI
1336: int
1.59 avsm 1337: mm_answer_gss_setup_ctx(int sock, Buffer *m)
1.46 markus 1338: {
1.59 avsm 1339: gss_OID_desc goid;
1.46 markus 1340: OM_uint32 major;
1341: u_int len;
1342:
1.164 djm 1343: if (!options.gss_authentication)
1344: fatal("%s: GSSAPI authentication not enabled", __func__);
1345:
1.59 avsm 1346: goid.elements = buffer_get_string(m, &len);
1347: goid.length = len;
1.46 markus 1348:
1.59 avsm 1349: major = ssh_gssapi_server_ctx(&gsscontext, &goid);
1.46 markus 1350:
1.124 djm 1351: free(goid.elements);
1.46 markus 1352:
1353: buffer_clear(m);
1354: buffer_put_int(m, major);
1355:
1.64 stevesk 1356: mm_request_send(sock, MONITOR_ANS_GSSSETUP, m);
1.46 markus 1357:
1358: /* Now we have a context, enable the step */
1359: monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 1);
1360:
1361: return (0);
1362: }
1363:
1364: int
1.59 avsm 1365: mm_answer_gss_accept_ctx(int sock, Buffer *m)
1.46 markus 1366: {
1367: gss_buffer_desc in;
1368: gss_buffer_desc out = GSS_C_EMPTY_BUFFER;
1.64 stevesk 1369: OM_uint32 major, minor;
1.46 markus 1370: OM_uint32 flags = 0; /* GSI needs this */
1.47 deraadt 1371: u_int len;
1.46 markus 1372:
1.164 djm 1373: if (!options.gss_authentication)
1374: fatal("%s: GSSAPI authentication not enabled", __func__);
1375:
1.47 deraadt 1376: in.value = buffer_get_string(m, &len);
1377: in.length = len;
1.46 markus 1378: major = ssh_gssapi_accept_ctx(gsscontext, &in, &out, &flags);
1.124 djm 1379: free(in.value);
1.46 markus 1380:
1381: buffer_clear(m);
1382: buffer_put_int(m, major);
1383: buffer_put_string(m, out.value, out.length);
1384: buffer_put_int(m, flags);
1.59 avsm 1385: mm_request_send(sock, MONITOR_ANS_GSSSTEP, m);
1.46 markus 1386:
1387: gss_release_buffer(&minor, &out);
1388:
1.64 stevesk 1389: if (major == GSS_S_COMPLETE) {
1.46 markus 1390: monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 0);
1391: monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
1.52 markus 1392: monitor_permit(mon_dispatch, MONITOR_REQ_GSSCHECKMIC, 1);
1.46 markus 1393: }
1394: return (0);
1395: }
1396:
1397: int
1.59 avsm 1398: mm_answer_gss_checkmic(int sock, Buffer *m)
1.52 markus 1399: {
1400: gss_buffer_desc gssbuf, mic;
1401: OM_uint32 ret;
1402: u_int len;
1.54 djm 1403:
1.164 djm 1404: if (!options.gss_authentication)
1405: fatal("%s: GSSAPI authentication not enabled", __func__);
1406:
1.52 markus 1407: gssbuf.value = buffer_get_string(m, &len);
1408: gssbuf.length = len;
1409: mic.value = buffer_get_string(m, &len);
1410: mic.length = len;
1.54 djm 1411:
1.52 markus 1412: ret = ssh_gssapi_checkmic(gsscontext, &gssbuf, &mic);
1.54 djm 1413:
1.124 djm 1414: free(gssbuf.value);
1415: free(mic.value);
1.54 djm 1416:
1.52 markus 1417: buffer_clear(m);
1418: buffer_put_int(m, ret);
1.54 djm 1419:
1.59 avsm 1420: mm_request_send(sock, MONITOR_ANS_GSSCHECKMIC, m);
1.54 djm 1421:
1.52 markus 1422: if (!GSS_ERROR(ret))
1423: monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
1.54 djm 1424:
1.52 markus 1425: return (0);
1426: }
1427:
1428: int
1.59 avsm 1429: mm_answer_gss_userok(int sock, Buffer *m)
1.46 markus 1430: {
1431: int authenticated;
1.164 djm 1432:
1433: if (!options.gss_authentication)
1434: fatal("%s: GSSAPI authentication not enabled", __func__);
1.46 markus 1435:
1436: authenticated = authctxt->valid && ssh_gssapi_userok(authctxt->user);
1437:
1438: buffer_clear(m);
1439: buffer_put_int(m, authenticated);
1440:
1441: debug3("%s: sending result %d", __func__, authenticated);
1.59 avsm 1442: mm_request_send(sock, MONITOR_ANS_GSSUSEROK, m);
1.46 markus 1443:
1.64 stevesk 1444: auth_method = "gssapi-with-mic";
1.46 markus 1445:
1446: /* Monitor loop will terminate if authenticated */
1447: return (authenticated);
1448: }
1449: #endif /* GSSAPI */
1.100 djm 1450:
![[BACK]](/icons/back.gif){kind=icon}
Return to monitor.c CVS log ![[TXT]](/icons/text.gif){kind=icon}
![[DIR]](/icons/dir.gif){kind=icon}
Up to [local] / src / usr.bin / ssh