Annotation of src/usr.bin/ssh/monitor.c, Revision 1.228
1.228 ! djm 1: /* $OpenBSD: monitor.c,v 1.227 2021/07/02 05:11:20 dtucker Exp $ */
1.1 provos 2: /*
3: * Copyright 2002 Niels Provos <provos@citi.umich.edu>
4: * Copyright 2002 Markus Friedl <markus@openbsd.org>
5: * All rights reserved.
6: *
7: * Redistribution and use in source and binary forms, with or without
8: * modification, are permitted provided that the following conditions
9: * are met:
10: * 1. Redistributions of source code must retain the above copyright
11: * notice, this list of conditions and the following disclaimer.
12: * 2. Redistributions in binary form must reproduce the above copyright
13: * notice, this list of conditions and the following disclaimer in the
14: * documentation and/or other materials provided with the distribution.
15: *
16: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
17: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
18: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
19: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
20: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
21: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
22: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
23: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
24: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
25: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
26: */
27:
1.67 stevesk 28: #include <sys/types.h>
29: #include <sys/wait.h>
1.79 stevesk 30: #include <sys/socket.h>
1.85 deraadt 31: #include <sys/tree.h>
1.95 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>
1.186 djm 50: #include <unistd.h>
1.1 provos 51:
1.114 djm 52: #include "atomicio.h"
1.85 deraadt 53: #include "xmalloc.h"
1.1 provos 54: #include "ssh.h"
1.185 markus 55: #include "sshkey.h"
1.183 markus 56: #include "sshbuf.h"
1.85 deraadt 57: #include "hostfile.h"
1.1 provos 58: #include "auth.h"
1.85 deraadt 59: #include "cipher.h"
1.1 provos 60: #include "kex.h"
61: #include "dh.h"
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"
1.203 djm 83: #include "sk-api.h"
1.189 djm 84:
1.46 markus 85: #ifdef GSSAPI
86: static Gssctxt *gsscontext = NULL;
87: #endif
88:
1.1 provos 89: /* Imports */
90: extern ServerOptions options;
91: extern u_int utmp_len;
1.181 markus 92: extern struct sshbuf *loginmsg;
1.180 djm 93: extern struct sshauthopt *auth_opts; /* XXX move to permanent ssh->authctxt? */
1.1 provos 94:
95: /* State exported from the child */
1.139 markus 96: static struct sshbuf *child_state;
1.1 provos 97:
1.43 markus 98: /* Functions on the monitor that answer unprivileged requests */
1.1 provos 99:
1.191 djm 100: int mm_answer_moduli(struct ssh *, int, struct sshbuf *);
101: int mm_answer_sign(struct ssh *, int, struct sshbuf *);
102: int mm_answer_pwnamallow(struct ssh *, int, struct sshbuf *);
103: int mm_answer_auth2_read_banner(struct ssh *, int, struct sshbuf *);
104: int mm_answer_authserv(struct ssh *, int, struct sshbuf *);
105: int mm_answer_authpassword(struct ssh *, int, struct sshbuf *);
106: int mm_answer_bsdauthquery(struct ssh *, int, struct sshbuf *);
107: int mm_answer_bsdauthrespond(struct ssh *, int, struct sshbuf *);
108: int mm_answer_keyallowed(struct ssh *, int, struct sshbuf *);
109: int mm_answer_keyverify(struct ssh *, int, struct sshbuf *);
110: int mm_answer_pty(struct ssh *, int, struct sshbuf *);
111: int mm_answer_pty_cleanup(struct ssh *, int, struct sshbuf *);
112: int mm_answer_term(struct ssh *, int, struct sshbuf *);
113: int mm_answer_rsa_keyallowed(struct ssh *, int, struct sshbuf *);
114: int mm_answer_rsa_challenge(struct ssh *, int, struct sshbuf *);
115: int mm_answer_rsa_response(struct ssh *, int, struct sshbuf *);
116: int mm_answer_sesskey(struct ssh *, int, struct sshbuf *);
117: int mm_answer_sessid(struct ssh *, int, struct sshbuf *);
1.1 provos 118:
1.46 markus 119: #ifdef GSSAPI
1.191 djm 120: int mm_answer_gss_setup_ctx(struct ssh *, int, struct sshbuf *);
121: int mm_answer_gss_accept_ctx(struct ssh *, int, struct sshbuf *);
122: int mm_answer_gss_userok(struct ssh *, int, struct sshbuf *);
123: int mm_answer_gss_checkmic(struct ssh *, int, struct sshbuf *);
1.46 markus 124: #endif
1.25 itojun 125:
1.1 provos 126: static Authctxt *authctxt;
1.132 markus 127:
1.1 provos 128: /* local state for key verify */
129: static u_char *key_blob = NULL;
1.183 markus 130: static size_t key_bloblen = 0;
1.224 djm 131: static u_int key_blobtype = MM_NOKEY;
1.180 djm 132: static struct sshauthopt *key_opts = NULL;
1.26 markus 133: static char *hostbased_cuser = NULL;
134: static char *hostbased_chost = NULL;
1.1 provos 135: static char *auth_method = "unknown";
1.119 djm 136: static char *auth_submethod = NULL;
1.44 markus 137: static u_int session_id2_len = 0;
1.13 markus 138: static u_char *session_id2 = NULL;
1.40 markus 139: static pid_t monitor_child_pid;
1.1 provos 140:
141: struct mon_table {
142: enum monitor_reqtype type;
143: int flags;
1.191 djm 144: int (*f)(struct ssh *, int, struct sshbuf *);
1.1 provos 145: };
146:
147: #define MON_ISAUTH 0x0004 /* Required for Authentication */
148: #define MON_AUTHDECIDE 0x0008 /* Decides Authentication */
149: #define MON_ONCE 0x0010 /* Disable after calling */
1.77 dtucker 150: #define MON_ALOG 0x0020 /* Log auth attempt without authenticating */
1.1 provos 151:
152: #define MON_AUTH (MON_ISAUTH|MON_AUTHDECIDE)
153:
154: #define MON_PERMIT 0x1000 /* Request is permitted */
155:
1.191 djm 156: static int monitor_read(struct ssh *, struct monitor *, struct mon_table *,
157: struct mon_table **);
158: static int monitor_read_log(struct monitor *);
159:
1.1 provos 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: static void
197: monitor_permit(struct mon_table *ent, enum monitor_reqtype type, int permit)
198: {
199: while (ent->f != NULL) {
200: if (ent->type == type) {
201: ent->flags &= ~MON_PERMIT;
202: ent->flags |= permit ? MON_PERMIT : 0;
203: return;
204: }
205: ent++;
206: }
207: }
208:
209: static void
210: monitor_permit_authentications(int permit)
211: {
212: struct mon_table *ent = mon_dispatch;
213:
214: while (ent->f != NULL) {
215: if (ent->flags & MON_AUTH) {
216: ent->flags &= ~MON_PERMIT;
217: ent->flags |= permit ? MON_PERMIT : 0;
218: }
219: ent++;
220: }
221: }
222:
1.50 markus 223: void
1.191 djm 224: monitor_child_preauth(struct ssh *ssh, struct monitor *pmonitor)
1.1 provos 225: {
226: struct mon_table *ent;
1.119 djm 227: int authenticated = 0, partial = 0;
1.1 provos 228:
229: debug3("preauth child monitor started");
230:
1.179 tb 231: if (pmonitor->m_recvfd >= 0)
232: close(pmonitor->m_recvfd);
233: if (pmonitor->m_log_sendfd >= 0)
234: close(pmonitor->m_log_sendfd);
1.114 djm 235: pmonitor->m_log_sendfd = pmonitor->m_recvfd = -1;
236:
1.191 djm 237: authctxt = (Authctxt *)ssh->authctxt;
1.50 markus 238: memset(authctxt, 0, sizeof(*authctxt));
1.180 djm 239: ssh->authctxt = authctxt;
1.50 markus 240:
1.162 markus 241: mon_dispatch = mon_dispatch_proto20;
242: /* Permit requests for moduli and signatures */
243: monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
244: monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
1.1 provos 245:
246: /* The first few requests do not require asynchronous access */
247: while (!authenticated) {
1.119 djm 248: partial = 0;
1.77 dtucker 249: auth_method = "unknown";
1.119 djm 250: auth_submethod = NULL;
1.172 djm 251: auth2_authctxt_reset_info(authctxt);
252:
1.191 djm 253: authenticated = (monitor_read(ssh, pmonitor,
254: mon_dispatch, &ent) == 1);
1.118 djm 255:
256: /* Special handling for multiple required authentications */
257: if (options.num_auth_methods != 0) {
258: if (authenticated &&
259: !auth2_update_methods_lists(authctxt,
1.122 markus 260: auth_method, auth_submethod)) {
1.217 djm 261: debug3_f("method %s: partial", auth_method);
1.118 djm 262: authenticated = 0;
1.119 djm 263: partial = 1;
1.118 djm 264: }
265: }
266:
1.1 provos 267: if (authenticated) {
268: if (!(ent->flags & MON_AUTHDECIDE))
1.217 djm 269: fatal_f("unexpected authentication from %d",
270: ent->type);
1.1 provos 271: if (authctxt->pw->pw_uid == 0 &&
1.180 djm 272: !auth_root_allowed(ssh, auth_method))
1.1 provos 273: authenticated = 0;
274: }
1.77 dtucker 275: if (ent->flags & (MON_AUTHDECIDE|MON_ALOG)) {
1.190 djm 276: auth_log(ssh, authenticated, partial,
1.125 djm 277: auth_method, auth_submethod);
1.150 djm 278: if (!partial && !authenticated)
1.1 provos 279: authctxt->failures++;
1.172 djm 280: if (authenticated || partial) {
281: auth2_update_session_info(authctxt,
282: auth_method, auth_submethod);
283: }
1.1 provos 284: }
285: }
286:
287: if (!authctxt->valid)
1.217 djm 288: fatal_f("authenticated invalid user");
1.77 dtucker 289: if (strcmp(auth_method, "unknown") == 0)
1.217 djm 290: fatal_f("authentication method name unknown");
1.1 provos 291:
1.217 djm 292: debug_f("user %s authenticated by privileged process", authctxt->user);
1.180 djm 293: ssh->authctxt = NULL;
1.167 djm 294: ssh_packet_set_log_preamble(ssh, "user %s", authctxt->user);
1.1 provos 295:
1.192 djm 296: mm_get_keystate(ssh, pmonitor);
1.120 markus 297:
298: /* Drain any buffered messages from the child */
299: while (pmonitor->m_log_recvfd != -1 && monitor_read_log(pmonitor) == 0)
300: ;
1.114 djm 301:
1.179 tb 302: if (pmonitor->m_recvfd >= 0)
303: close(pmonitor->m_recvfd);
304: if (pmonitor->m_log_sendfd >= 0)
305: close(pmonitor->m_log_sendfd);
1.114 djm 306: pmonitor->m_sendfd = pmonitor->m_log_recvfd = -1;
1.1 provos 307: }
308:
1.40 markus 309: static void
310: monitor_set_child_handler(pid_t pid)
311: {
312: monitor_child_pid = pid;
313: }
314:
315: static void
1.59 avsm 316: monitor_child_handler(int sig)
1.40 markus 317: {
1.59 avsm 318: kill(monitor_child_pid, sig);
1.40 markus 319: }
320:
1.1 provos 321: void
1.191 djm 322: monitor_child_postauth(struct ssh *ssh, struct monitor *pmonitor)
1.1 provos 323: {
1.114 djm 324: close(pmonitor->m_recvfd);
325: pmonitor->m_recvfd = -1;
326:
1.40 markus 327: monitor_set_child_handler(pmonitor->m_pid);
1.207 dtucker 328: ssh_signal(SIGHUP, &monitor_child_handler);
329: ssh_signal(SIGTERM, &monitor_child_handler);
330: ssh_signal(SIGINT, &monitor_child_handler);
1.40 markus 331:
1.162 markus 332: mon_dispatch = mon_dispatch_postauth20;
333:
334: /* Permit requests for moduli and signatures */
335: monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
336: monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
337: monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1);
1.1 provos 338:
1.180 djm 339: if (auth_opts->permit_pty_flag) {
1.1 provos 340: monitor_permit(mon_dispatch, MONITOR_REQ_PTY, 1);
341: monitor_permit(mon_dispatch, MONITOR_REQ_PTYCLEANUP, 1);
342: }
343:
344: for (;;)
1.191 djm 345: monitor_read(ssh, pmonitor, mon_dispatch, NULL);
1.1 provos 346: }
347:
1.114 djm 348: static int
349: monitor_read_log(struct monitor *pmonitor)
350: {
1.183 markus 351: struct sshbuf *logmsg;
1.225 markus 352: u_int len, level, forced;
353: char *msg;
1.183 markus 354: u_char *p;
355: int r;
1.114 djm 356:
1.183 markus 357: if ((logmsg = sshbuf_new()) == NULL)
1.217 djm 358: fatal_f("sshbuf_new");
1.114 djm 359:
360: /* Read length */
1.183 markus 361: if ((r = sshbuf_reserve(logmsg, 4, &p)) != 0)
1.217 djm 362: fatal_fr(r, "reserve len");
1.183 markus 363: if (atomicio(read, pmonitor->m_log_recvfd, p, 4) != 4) {
1.114 djm 364: if (errno == EPIPE) {
1.183 markus 365: sshbuf_free(logmsg);
1.217 djm 366: debug_f("child log fd closed");
1.114 djm 367: close(pmonitor->m_log_recvfd);
368: pmonitor->m_log_recvfd = -1;
369: return -1;
370: }
1.217 djm 371: fatal_f("log fd read: %s", strerror(errno));
1.114 djm 372: }
1.183 markus 373: if ((r = sshbuf_get_u32(logmsg, &len)) != 0)
1.217 djm 374: fatal_fr(r, "parse len");
1.114 djm 375: if (len <= 4 || len > 8192)
1.217 djm 376: fatal_f("invalid log message length %u", len);
1.114 djm 377:
378: /* Read severity, message */
1.183 markus 379: sshbuf_reset(logmsg);
380: if ((r = sshbuf_reserve(logmsg, len, &p)) != 0)
1.217 djm 381: fatal_fr(r, "reserve msg");
1.183 markus 382: if (atomicio(read, pmonitor->m_log_recvfd, p, len) != len)
1.217 djm 383: fatal_f("log fd read: %s", strerror(errno));
1.225 markus 384: if ((r = sshbuf_get_u32(logmsg, &level)) != 0 ||
385: (r = sshbuf_get_u32(logmsg, &forced)) != 0 ||
1.183 markus 386: (r = sshbuf_get_cstring(logmsg, &msg, NULL)) != 0)
1.217 djm 387: fatal_fr(r, "parse");
1.114 djm 388:
389: /* Log it */
390: if (log_level_name(level) == NULL)
1.216 djm 391: fatal_f("invalid log level %u (corrupted message?)", level);
1.225 markus 392: sshlogdirect(level, forced, "%s [preauth]", msg);
1.114 djm 393:
1.183 markus 394: sshbuf_free(logmsg);
1.124 djm 395: free(msg);
1.114 djm 396:
397: return 0;
398: }
399:
1.191 djm 400: static int
401: monitor_read(struct ssh *ssh, struct monitor *pmonitor, struct mon_table *ent,
1.1 provos 402: struct mon_table **pent)
403: {
1.183 markus 404: struct sshbuf *m;
405: int r, ret;
1.1 provos 406: u_char type;
1.114 djm 407: struct pollfd pfd[2];
408:
409: for (;;) {
1.130 tedu 410: memset(&pfd, 0, sizeof(pfd));
1.114 djm 411: pfd[0].fd = pmonitor->m_sendfd;
412: pfd[0].events = POLLIN;
413: pfd[1].fd = pmonitor->m_log_recvfd;
414: pfd[1].events = pfd[1].fd == -1 ? 0 : POLLIN;
1.115 djm 415: if (poll(pfd, pfd[1].fd == -1 ? 1 : 2, -1) == -1) {
416: if (errno == EINTR || errno == EAGAIN)
417: continue;
1.217 djm 418: fatal_f("poll: %s", strerror(errno));
1.115 djm 419: }
1.114 djm 420: if (pfd[1].revents) {
421: /*
422: * Drain all log messages before processing next
423: * monitor request.
424: */
425: monitor_read_log(pmonitor);
426: continue;
427: }
428: if (pfd[0].revents)
429: break; /* Continues below */
430: }
1.1 provos 431:
1.183 markus 432: if ((m = sshbuf_new()) == NULL)
1.217 djm 433: fatal_f("sshbuf_new");
1.1 provos 434:
1.183 markus 435: mm_request_receive(pmonitor->m_sendfd, m);
436: if ((r = sshbuf_get_u8(m, &type)) != 0)
1.217 djm 437: fatal_fr(r, "parse type");
1.1 provos 438:
1.217 djm 439: debug3_f("checking request %d", type);
1.1 provos 440:
441: while (ent->f != NULL) {
442: if (ent->type == type)
443: break;
444: ent++;
445: }
446:
447: if (ent->f != NULL) {
448: if (!(ent->flags & MON_PERMIT))
1.217 djm 449: fatal_f("unpermitted request %d", type);
1.191 djm 450: ret = (*ent->f)(ssh, pmonitor->m_sendfd, m);
1.183 markus 451: sshbuf_free(m);
1.1 provos 452:
453: /* The child may use this request only once, disable it */
454: if (ent->flags & MON_ONCE) {
1.217 djm 455: debug2_f("%d used once, disabling now", type);
1.1 provos 456: ent->flags &= ~MON_PERMIT;
457: }
458:
459: if (pent != NULL)
460: *pent = ent;
1.3 markus 461:
1.1 provos 462: return ret;
463: }
464:
1.217 djm 465: fatal_f("unsupported request: %d", type);
1.1 provos 466:
467: /* NOTREACHED */
468: return (-1);
469: }
470:
471: /* allowed key state */
472: static int
1.203 djm 473: monitor_allowed_key(const u_char *blob, u_int bloblen)
1.1 provos 474: {
475: /* make sure key is allowed */
476: if (key_blob == NULL || key_bloblen != bloblen ||
1.108 djm 477: timingsafe_bcmp(key_blob, blob, key_bloblen))
1.1 provos 478: return (0);
479: return (1);
480: }
481:
482: static void
483: monitor_reset_key_state(void)
484: {
485: /* reset state */
1.124 djm 486: free(key_blob);
487: free(hostbased_cuser);
488: free(hostbased_chost);
1.180 djm 489: sshauthopt_free(key_opts);
1.1 provos 490: key_blob = NULL;
491: key_bloblen = 0;
492: key_blobtype = MM_NOKEY;
1.180 djm 493: key_opts = NULL;
1.1 provos 494: hostbased_cuser = NULL;
495: hostbased_chost = NULL;
496: }
497:
1.132 markus 498: #ifdef WITH_OPENSSL
1.1 provos 499: int
1.191 djm 500: mm_answer_moduli(struct ssh *ssh, int sock, struct sshbuf *m)
1.1 provos 501: {
502: DH *dh;
1.187 djm 503: const BIGNUM *dh_p, *dh_g;
1.183 markus 504: int r;
505: u_int min, want, max;
1.1 provos 506:
1.183 markus 507: if ((r = sshbuf_get_u32(m, &min)) != 0 ||
508: (r = sshbuf_get_u32(m, &want)) != 0 ||
509: (r = sshbuf_get_u32(m, &max)) != 0)
1.217 djm 510: fatal_fr(r, "parse");
1.1 provos 511:
1.217 djm 512: debug3_f("got parameters: %d %d %d", min, want, max);
1.1 provos 513: /* We need to check here, too, in case the child got corrupted */
514: if (max < min || want < min || max < want)
1.217 djm 515: fatal_f("bad parameters: %d %d %d", min, want, max);
1.1 provos 516:
1.183 markus 517: sshbuf_reset(m);
1.1 provos 518:
519: dh = choose_dh(min, want, max);
520: if (dh == NULL) {
1.183 markus 521: if ((r = sshbuf_put_u8(m, 0)) != 0)
1.217 djm 522: fatal_fr(r, "assemble empty");
1.1 provos 523: return (0);
524: } else {
525: /* Send first bignum */
1.187 djm 526: DH_get0_pqg(dh, &dh_p, NULL, &dh_g);
1.183 markus 527: if ((r = sshbuf_put_u8(m, 1)) != 0 ||
1.187 djm 528: (r = sshbuf_put_bignum2(m, dh_p)) != 0 ||
529: (r = sshbuf_put_bignum2(m, dh_g)) != 0)
1.217 djm 530: fatal_fr(r, "assemble");
1.3 markus 531:
1.1 provos 532: DH_free(dh);
533: }
1.59 avsm 534: mm_request_send(sock, MONITOR_ANS_MODULI, m);
1.1 provos 535: return (0);
536: }
1.132 markus 537: #endif
1.1 provos 538:
539: int
1.191 djm 540: mm_answer_sign(struct ssh *ssh, int sock, struct sshbuf *m)
1.1 provos 541: {
1.138 djm 542: extern int auth_sock; /* XXX move to state struct? */
543: struct sshkey *key;
1.157 djm 544: struct sshbuf *sigbuf = NULL;
545: u_char *p = NULL, *signature = NULL;
546: char *alg = NULL;
1.155 markus 547: size_t datlen, siglen, alglen;
1.159 djm 548: int r, is_proof = 0;
1.185 markus 549: u_int keyid, compat;
1.145 djm 550: const char proof_req[] = "hostkeys-prove-00@openssh.com";
1.3 markus 551:
1.217 djm 552: debug3_f("entering");
1.1 provos 553:
1.138 djm 554: if ((r = sshbuf_get_u32(m, &keyid)) != 0 ||
1.155 markus 555: (r = sshbuf_get_string(m, &p, &datlen)) != 0 ||
1.185 markus 556: (r = sshbuf_get_cstring(m, &alg, &alglen)) != 0 ||
557: (r = sshbuf_get_u32(m, &compat)) != 0)
1.217 djm 558: fatal_fr(r, "parse");
1.159 djm 559: if (keyid > INT_MAX)
1.217 djm 560: fatal_f("invalid key ID");
1.1 provos 561:
1.69 djm 562: /*
1.110 djm 563: * Supported KEX types use SHA1 (20 bytes), SHA256 (32 bytes),
564: * SHA384 (48 bytes) and SHA512 (64 bytes).
1.144 djm 565: *
566: * Otherwise, verify the signature request is for a hostkey
567: * proof.
568: *
569: * XXX perform similar check for KEX signature requests too?
570: * it's not trivial, since what is signed is the hash, rather
571: * than the full kex structure...
1.69 djm 572: */
1.144 djm 573: if (datlen != 20 && datlen != 32 && datlen != 48 && datlen != 64) {
574: /*
575: * Construct expected hostkey proof and compare it to what
576: * the client sent us.
577: */
578: if (session_id2_len == 0) /* hostkeys is never first */
1.217 djm 579: fatal_f("bad data length: %zu", datlen);
1.144 djm 580: if ((key = get_hostkey_public_by_index(keyid, ssh)) == NULL)
1.217 djm 581: fatal_f("no hostkey for index %d", keyid);
1.144 djm 582: if ((sigbuf = sshbuf_new()) == NULL)
1.217 djm 583: fatal_f("sshbuf_new");
1.145 djm 584: if ((r = sshbuf_put_cstring(sigbuf, proof_req)) != 0 ||
585: (r = sshbuf_put_string(sigbuf, session_id2,
1.152 jsg 586: session_id2_len)) != 0 ||
1.144 djm 587: (r = sshkey_puts(key, sigbuf)) != 0)
1.217 djm 588: fatal_fr(r, "assemble private key proof");
1.144 djm 589: if (datlen != sshbuf_len(sigbuf) ||
590: memcmp(p, sshbuf_ptr(sigbuf), sshbuf_len(sigbuf)) != 0)
1.217 djm 591: fatal_f("bad data length: %zu, hostkey proof len %zu",
592: datlen, sshbuf_len(sigbuf));
1.144 djm 593: sshbuf_free(sigbuf);
594: is_proof = 1;
595: }
1.1 provos 596:
1.13 markus 597: /* save session id, it will be passed on the first call */
598: if (session_id2_len == 0) {
599: session_id2_len = datlen;
600: session_id2 = xmalloc(session_id2_len);
601: memcpy(session_id2, p, session_id2_len);
602: }
603:
1.127 markus 604: if ((key = get_hostkey_by_index(keyid)) != NULL) {
1.155 markus 605: if ((r = sshkey_sign(key, &signature, &siglen, p, datlen, alg,
1.213 djm 606: options.sk_provider, NULL, compat)) != 0)
1.217 djm 607: fatal_fr(r, "sign");
1.144 djm 608: } else if ((key = get_hostkey_public_by_index(keyid, ssh)) != NULL &&
1.138 djm 609: auth_sock > 0) {
610: if ((r = ssh_agent_sign(auth_sock, key, &signature, &siglen,
1.217 djm 611: p, datlen, alg, compat)) != 0)
612: fatal_fr(r, "agent sign");
1.127 markus 613: } else
1.217 djm 614: fatal_f("no hostkey from index %d", keyid);
1.1 provos 615:
1.228 ! djm 616: debug3_f("%s %s signature len=%zu", alg,
! 617: is_proof ? "hostkey proof" : "KEX", siglen);
1.1 provos 618:
1.138 djm 619: sshbuf_reset(m);
620: if ((r = sshbuf_put_string(m, signature, siglen)) != 0)
1.217 djm 621: fatal_fr(r, "assemble");
1.1 provos 622:
1.157 djm 623: free(alg);
1.124 djm 624: free(p);
625: free(signature);
1.1 provos 626:
1.59 avsm 627: mm_request_send(sock, MONITOR_ANS_SIGN, m);
1.1 provos 628:
629: /* Turn on permissions for getpwnam */
630: monitor_permit(mon_dispatch, MONITOR_REQ_PWNAM, 1);
631:
632: return (0);
633: }
634:
1.218 djm 635: #define PUTPW(b, id) \
636: do { \
637: if ((r = sshbuf_put_string(b, \
638: &pwent->id, sizeof(pwent->id))) != 0) \
639: fatal_fr(r, "assemble %s", #id); \
640: } while (0)
641:
1.1 provos 642: /* Retrieves the password entry and also checks if the user is permitted */
643: int
1.191 djm 644: mm_answer_pwnamallow(struct ssh *ssh, int sock, struct sshbuf *m)
1.1 provos 645: {
1.60 dtucker 646: char *username;
1.1 provos 647: struct passwd *pwent;
1.183 markus 648: int r, allowed = 0;
1.113 djm 649: u_int i;
1.3 markus 650:
1.217 djm 651: debug3_f("entering");
1.1 provos 652:
653: if (authctxt->attempt++ != 0)
1.217 djm 654: fatal_f("multiple attempts for getpwnam");
1.1 provos 655:
1.183 markus 656: if ((r = sshbuf_get_cstring(m, &username, NULL)) != 0)
1.217 djm 657: fatal_fr(r, "parse");
1.1 provos 658:
1.190 djm 659: pwent = getpwnamallow(ssh, username);
1.1 provos 660:
1.60 dtucker 661: authctxt->user = xstrdup(username);
662: setproctitle("%s [priv]", pwent ? username : "unknown");
1.124 djm 663: free(username);
1.1 provos 664:
1.183 markus 665: sshbuf_reset(m);
1.1 provos 666:
667: if (pwent == NULL) {
1.183 markus 668: if ((r = sshbuf_put_u8(m, 0)) != 0)
1.217 djm 669: fatal_fr(r, "assemble fakepw");
1.53 djm 670: authctxt->pw = fakepw();
1.1 provos 671: goto out;
672: }
673:
674: allowed = 1;
1.4 markus 675: authctxt->pw = pwent;
1.1 provos 676: authctxt->valid = 1;
677:
1.218 djm 678: /* XXX send fake class/dir/shell, etc. */
679: if ((r = sshbuf_put_u8(m, 1)) != 0)
680: fatal_fr(r, "assemble ok");
681: PUTPW(m, pw_uid);
682: PUTPW(m, pw_gid);
683: PUTPW(m, pw_change);
684: PUTPW(m, pw_expire);
685: if ((r = sshbuf_put_cstring(m, pwent->pw_name)) != 0 ||
1.183 markus 686: (r = sshbuf_put_cstring(m, "*")) != 0 ||
687: (r = sshbuf_put_cstring(m, pwent->pw_gecos)) != 0 ||
688: (r = sshbuf_put_cstring(m, pwent->pw_class)) != 0 ||
689: (r = sshbuf_put_cstring(m, pwent->pw_dir)) != 0 ||
690: (r = sshbuf_put_cstring(m, pwent->pw_shell)) != 0)
1.217 djm 691: fatal_fr(r, "assemble pw");
1.94 dtucker 692:
693: out:
1.167 djm 694: ssh_packet_set_log_preamble(ssh, "%suser %s",
695: authctxt->valid ? "authenticating" : "invalid ", authctxt->user);
1.183 markus 696: if ((r = sshbuf_put_string(m, &options, sizeof(options))) != 0)
1.217 djm 697: fatal_fr(r, "assemble options");
1.112 djm 698:
699: #define M_CP_STROPT(x) do { \
1.217 djm 700: if (options.x != NULL && \
701: (r = sshbuf_put_cstring(m, options.x)) != 0) \
702: fatal_fr(r, "assemble %s", #x); \
1.112 djm 703: } while (0)
1.113 djm 704: #define M_CP_STRARRAYOPT(x, nx) do { \
1.183 markus 705: for (i = 0; i < options.nx; i++) { \
706: if ((r = sshbuf_put_cstring(m, options.x[i])) != 0) \
1.217 djm 707: fatal_fr(r, "assemble %s", #x); \
1.183 markus 708: } \
1.113 djm 709: } while (0)
1.112 djm 710: /* See comment in servconf.h */
711: COPY_MATCH_STRING_OPTS();
712: #undef M_CP_STROPT
1.113 djm 713: #undef M_CP_STRARRAYOPT
1.118 djm 714:
715: /* Create valid auth method lists */
1.162 markus 716: if (auth2_setup_methods_lists(authctxt) != 0) {
1.118 djm 717: /*
718: * The monitor will continue long enough to let the child
719: * run to it's packet_disconnect(), but it must not allow any
720: * authentication to succeed.
721: */
1.217 djm 722: debug_f("no valid authentication method lists");
1.118 djm 723: }
724:
1.217 djm 725: debug3_f("sending MONITOR_ANS_PWNAM: %d", allowed);
1.59 avsm 726: mm_request_send(sock, MONITOR_ANS_PWNAM, m);
1.1 provos 727:
1.162 markus 728: /* Allow service/style information on the auth context */
729: monitor_permit(mon_dispatch, MONITOR_REQ_AUTHSERV, 1);
730: monitor_permit(mon_dispatch, MONITOR_REQ_AUTH2_READ_BANNER, 1);
1.10 djm 731:
732: return (0);
733: }
734:
1.191 djm 735: int mm_answer_auth2_read_banner(struct ssh *ssh, int sock, struct sshbuf *m)
1.10 djm 736: {
737: char *banner;
1.183 markus 738: int r;
1.10 djm 739:
1.183 markus 740: sshbuf_reset(m);
1.10 djm 741: banner = auth2_read_banner();
1.183 markus 742: if ((r = sshbuf_put_cstring(m, banner != NULL ? banner : "")) != 0)
1.217 djm 743: fatal_fr(r, "assemble");
1.59 avsm 744: mm_request_send(sock, MONITOR_ANS_AUTH2_READ_BANNER, m);
1.124 djm 745: free(banner);
1.1 provos 746:
747: return (0);
748: }
749:
750: int
1.191 djm 751: mm_answer_authserv(struct ssh *ssh, int sock, struct sshbuf *m)
1.1 provos 752: {
1.183 markus 753: int r;
754:
1.1 provos 755: monitor_permit_authentications(1);
756:
1.183 markus 757: if ((r = sshbuf_get_cstring(m, &authctxt->service, NULL)) != 0 ||
758: (r = sshbuf_get_cstring(m, &authctxt->style, NULL)) != 0)
1.217 djm 759: fatal_fr(r, "parse");
760: debug3_f("service=%s, style=%s", authctxt->service, authctxt->style);
1.6 stevesk 761:
1.1 provos 762: if (strlen(authctxt->style) == 0) {
1.124 djm 763: free(authctxt->style);
1.1 provos 764: authctxt->style = NULL;
765: }
766:
767: return (0);
768: }
769:
770: int
1.191 djm 771: mm_answer_authpassword(struct ssh *ssh, int sock, struct sshbuf *m)
1.1 provos 772: {
773: static int call_count;
774: char *passwd;
1.183 markus 775: int r, authenticated;
776: size_t plen;
1.1 provos 777:
1.164 djm 778: if (!options.password_authentication)
1.217 djm 779: fatal_f("password authentication not enabled");
1.183 markus 780: if ((r = sshbuf_get_cstring(m, &passwd, &plen)) != 0)
1.217 djm 781: fatal_fr(r, "parse");
1.1 provos 782: /* Only authenticate if the context is valid */
1.12 markus 783: authenticated = options.password_authentication &&
1.180 djm 784: auth_password(ssh, passwd);
1.209 jsg 785: freezero(passwd, plen);
1.1 provos 786:
1.183 markus 787: sshbuf_reset(m);
788: if ((r = sshbuf_put_u32(m, authenticated)) != 0)
1.217 djm 789: fatal_fr(r, "assemble");
1.1 provos 790:
1.217 djm 791: debug3_f("sending result %d", authenticated);
1.59 avsm 792: mm_request_send(sock, MONITOR_ANS_AUTHPASSWORD, m);
1.1 provos 793:
794: call_count++;
795: if (plen == 0 && call_count == 1)
796: auth_method = "none";
797: else
798: auth_method = "password";
799:
800: /* Causes monitor loop to terminate if authenticated */
801: return (authenticated);
802: }
803:
804: int
1.191 djm 805: mm_answer_bsdauthquery(struct ssh *ssh, int sock, struct sshbuf *m)
1.1 provos 806: {
807: char *name, *infotxt;
1.183 markus 808: u_int numprompts, *echo_on, success;
1.1 provos 809: char **prompts;
1.183 markus 810: int r;
1.1 provos 811:
1.164 djm 812: if (!options.kbd_interactive_authentication)
1.217 djm 813: fatal_f("kbd-int authentication not enabled");
1.31 markus 814: success = bsdauth_query(authctxt, &name, &infotxt, &numprompts,
815: &prompts, &echo_on) < 0 ? 0 : 1;
1.1 provos 816:
1.183 markus 817: sshbuf_reset(m);
818: if ((r = sshbuf_put_u32(m, success)) != 0)
1.217 djm 819: fatal_fr(r, "assemble");
1.183 markus 820: if (success) {
821: if ((r = sshbuf_put_cstring(m, prompts[0])) != 0)
1.217 djm 822: fatal_fr(r, "assemble prompt");
1.183 markus 823: }
1.1 provos 824:
1.217 djm 825: debug3_f("sending challenge success: %u", success);
1.59 avsm 826: mm_request_send(sock, MONITOR_ANS_BSDAUTHQUERY, m);
1.1 provos 827:
1.31 markus 828: if (success) {
1.124 djm 829: free(name);
830: free(infotxt);
831: free(prompts);
832: free(echo_on);
1.1 provos 833: }
834:
835: return (0);
836: }
837:
838: int
1.191 djm 839: mm_answer_bsdauthrespond(struct ssh *ssh, int sock, struct sshbuf *m)
1.1 provos 840: {
841: char *response;
1.183 markus 842: int r, authok;
1.1 provos 843:
1.164 djm 844: if (!options.kbd_interactive_authentication)
1.217 djm 845: fatal_f("kbd-int authentication not enabled");
1.154 mmcc 846: if (authctxt->as == NULL)
1.217 djm 847: fatal_f("no bsd auth session");
1.1 provos 848:
1.183 markus 849: if ((r = sshbuf_get_cstring(m, &response, NULL)) != 0)
1.217 djm 850: fatal_fr(r, "parse");
1.227 dtucker 851: authok = options.kbd_interactive_authentication &&
1.12 markus 852: auth_userresponse(authctxt->as, response, 0);
1.1 provos 853: authctxt->as = NULL;
1.217 djm 854: debug3_f("<%s> = <%d>", response, authok);
1.124 djm 855: free(response);
1.1 provos 856:
1.183 markus 857: sshbuf_reset(m);
858: if ((r = sshbuf_put_u32(m, authok)) != 0)
1.217 djm 859: fatal_fr(r, "assemble");
1.1 provos 860:
1.217 djm 861: debug3_f("sending authenticated: %d", authok);
1.59 avsm 862: mm_request_send(sock, MONITOR_ANS_BSDAUTHRESPOND, m);
1.1 provos 863:
1.162 markus 864: auth_method = "keyboard-interactive";
865: auth_submethod = "bsdauth";
1.1 provos 866:
867: return (authok != 0);
868: }
869:
1.188 djm 870: /*
871: * Check that the key type appears in the supplied pattern list, ignoring
872: * mismatches in the signature algorithm. (Signature algorithm checks are
873: * performed in the unprivileged authentication code).
874: * Returns 1 on success, 0 otherwise.
875: */
876: static int
877: key_base_type_match(const char *method, const struct sshkey *key,
878: const char *list)
879: {
880: char *s, *l, *ol = xstrdup(list);
881: int found = 0;
882:
883: l = ol;
884: for ((s = strsep(&l, ",")); s && *s != '\0'; (s = strsep(&l, ","))) {
885: if (sshkey_type_from_name(s) == key->type) {
886: found = 1;
887: break;
888: }
889: }
890: if (!found) {
891: error("%s key type %s is not in permitted list %s", method,
892: sshkey_ssh_name(key), list);
893: }
894:
895: free(ol);
896: return found;
897: }
898:
1.1 provos 899: int
1.191 djm 900: mm_answer_keyallowed(struct ssh *ssh, int sock, struct sshbuf *m)
1.1 provos 901: {
1.183 markus 902: struct sshkey *key = NULL;
1.26 markus 903: char *cuser, *chost;
1.183 markus 904: u_int pubkey_auth_attempt;
1.224 djm 905: u_int type = 0;
1.180 djm 906: int r, allowed = 0;
907: struct sshauthopt *opts = NULL;
1.1 provos 908:
1.217 djm 909: debug3_f("entering");
1.183 markus 910: if ((r = sshbuf_get_u32(m, &type)) != 0 ||
911: (r = sshbuf_get_cstring(m, &cuser, NULL)) != 0 ||
912: (r = sshbuf_get_cstring(m, &chost, NULL)) != 0 ||
913: (r = sshkey_froms(m, &key)) != 0 ||
914: (r = sshbuf_get_u32(m, &pubkey_auth_attempt)) != 0)
1.217 djm 915: fatal_fr(r, "parse");
1.1 provos 916:
1.51 djm 917: if (key != NULL && authctxt->valid) {
1.137 djm 918: /* These should not make it past the privsep child */
1.185 markus 919: if (sshkey_type_plain(key->type) == KEY_RSA &&
1.222 djm 920: (ssh->compat & SSH_BUG_RSASIGMD5) != 0)
1.217 djm 921: fatal_f("passed a SSH_BUG_RSASIGMD5 key");
1.137 djm 922:
1.63 deraadt 923: switch (type) {
1.1 provos 924: case MM_USERKEY:
1.77 dtucker 925: auth_method = "publickey";
1.180 djm 926: if (!options.pubkey_authentication)
927: break;
928: if (auth2_key_already_used(authctxt, key))
929: break;
1.188 djm 930: if (!key_base_type_match(auth_method, key,
1.220 dtucker 931: options.pubkey_accepted_algos))
1.180 djm 932: break;
933: allowed = user_key_allowed(ssh, authctxt->pw, key,
934: pubkey_auth_attempt, &opts);
1.1 provos 935: break;
936: case MM_HOSTKEY:
1.180 djm 937: auth_method = "hostbased";
938: if (!options.hostbased_authentication)
939: break;
940: if (auth2_key_already_used(authctxt, key))
941: break;
1.188 djm 942: if (!key_base_type_match(auth_method, key,
1.221 dtucker 943: options.hostbased_accepted_algos))
1.180 djm 944: break;
1.192 djm 945: allowed = hostbased_key_allowed(ssh, authctxt->pw,
1.1 provos 946: cuser, chost, key);
1.172 djm 947: auth2_record_info(authctxt,
1.126 djm 948: "client user \"%.100s\", client host \"%.100s\"",
949: cuser, chost);
1.1 provos 950: break;
951: default:
1.224 djm 952: fatal_f("unknown key type %u", type);
1.1 provos 953: break;
954: }
1.33 markus 955: }
1.161 djm 956:
1.217 djm 957: debug3_f("%s authentication%s: %s key is %s", auth_method,
958: pubkey_auth_attempt ? "" : " test",
1.180 djm 959: (key == NULL || !authctxt->valid) ? "invalid" : sshkey_type(key),
960: allowed ? "allowed" : "not allowed");
1.161 djm 961:
1.172 djm 962: auth2_record_key(authctxt, 0, key);
1.1 provos 963:
964: /* clear temporarily storage (used by verify) */
965: monitor_reset_key_state();
966:
967: if (allowed) {
968: /* Save temporarily for comparison in verify */
1.183 markus 969: if ((r = sshkey_to_blob(key, &key_blob, &key_bloblen)) != 0)
1.217 djm 970: fatal_fr(r, "sshkey_to_blob");
1.1 provos 971: key_blobtype = type;
1.180 djm 972: key_opts = opts;
1.1 provos 973: hostbased_cuser = cuser;
974: hostbased_chost = chost;
1.72 djm 975: } else {
1.77 dtucker 976: /* Log failed attempt */
1.190 djm 977: auth_log(ssh, 0, 0, auth_method, NULL);
1.124 djm 978: free(cuser);
979: free(chost);
1.1 provos 980: }
1.183 markus 981: sshkey_free(key);
1.1 provos 982:
1.183 markus 983: sshbuf_reset(m);
984: if ((r = sshbuf_put_u32(m, allowed)) != 0)
1.217 djm 985: fatal_fr(r, "assemble");
1.180 djm 986: if (opts != NULL && (r = sshauthopt_serialise(opts, m, 1)) != 0)
1.217 djm 987: fatal_fr(r, "sshauthopt_serialise");
1.180 djm 988: mm_request_send(sock, MONITOR_ANS_KEYALLOWED, m);
1.1 provos 989:
1.180 djm 990: if (!allowed)
991: sshauthopt_free(opts);
1.1 provos 992:
993: return (0);
994: }
995:
996: static int
1.222 djm 997: monitor_valid_userblob(struct ssh *ssh, const u_char *data, u_int datalen)
1.1 provos 998: {
1.183 markus 999: struct sshbuf *b;
1000: const u_char *p;
1.159 djm 1001: char *userstyle, *cp;
1.183 markus 1002: size_t len;
1003: u_char type;
1004: int r, fail = 0;
1.1 provos 1005:
1.203 djm 1006: if ((b = sshbuf_from(data, datalen)) == NULL)
1.217 djm 1007: fatal_f("sshbuf_from");
1.3 markus 1008:
1.222 djm 1009: if (ssh->compat & SSH_OLD_SESSIONID) {
1.183 markus 1010: p = sshbuf_ptr(b);
1011: len = sshbuf_len(b);
1.13 markus 1012: if ((session_id2 == NULL) ||
1013: (len < session_id2_len) ||
1.108 djm 1014: (timingsafe_bcmp(p, session_id2, session_id2_len) != 0))
1.13 markus 1015: fail++;
1.183 markus 1016: if ((r = sshbuf_consume(b, session_id2_len)) != 0)
1.217 djm 1017: fatal_fr(r, "consume");
1.1 provos 1018: } else {
1.183 markus 1019: if ((r = sshbuf_get_string_direct(b, &p, &len)) != 0)
1.217 djm 1020: fatal_fr(r, "parse sessionid");
1.13 markus 1021: if ((session_id2 == NULL) ||
1022: (len != session_id2_len) ||
1.108 djm 1023: (timingsafe_bcmp(p, session_id2, session_id2_len) != 0))
1.1 provos 1024: fail++;
1025: }
1.183 markus 1026: if ((r = sshbuf_get_u8(b, &type)) != 0)
1.217 djm 1027: fatal_fr(r, "parse type");
1.183 markus 1028: if (type != SSH2_MSG_USERAUTH_REQUEST)
1.1 provos 1029: fail++;
1.183 markus 1030: if ((r = sshbuf_get_cstring(b, &cp, NULL)) != 0)
1.217 djm 1031: fatal_fr(r, "parse userstyle");
1.121 djm 1032: xasprintf(&userstyle, "%s%s%s", authctxt->user,
1033: authctxt->style ? ":" : "",
1034: authctxt->style ? authctxt->style : "");
1.159 djm 1035: if (strcmp(userstyle, cp) != 0) {
1036: logit("wrong user name passed to monitor: "
1037: "expected %s != %.100s", userstyle, cp);
1.1 provos 1038: fail++;
1039: }
1.124 djm 1040: free(userstyle);
1.159 djm 1041: free(cp);
1.183 markus 1042: if ((r = sshbuf_skip_string(b)) != 0 || /* service */
1043: (r = sshbuf_get_cstring(b, &cp, NULL)) != 0)
1.217 djm 1044: fatal_fr(r, "parse method");
1.178 djm 1045: if (strcmp("publickey", cp) != 0)
1046: fail++;
1047: free(cp);
1.183 markus 1048: if ((r = sshbuf_get_u8(b, &type)) != 0)
1.217 djm 1049: fatal_fr(r, "parse pktype");
1.183 markus 1050: if (type == 0)
1.178 djm 1051: fail++;
1.183 markus 1052: if ((r = sshbuf_skip_string(b)) != 0 || /* pkalg */
1053: (r = sshbuf_skip_string(b)) != 0) /* pkblob */
1.217 djm 1054: fatal_fr(r, "parse pk");
1.183 markus 1055: if (sshbuf_len(b) != 0)
1.1 provos 1056: fail++;
1.183 markus 1057: sshbuf_free(b);
1.1 provos 1058: return (fail == 0);
1059: }
1060:
1061: static int
1.203 djm 1062: monitor_valid_hostbasedblob(const u_char *data, u_int datalen,
1063: const char *cuser, const char *chost)
1.1 provos 1064: {
1.183 markus 1065: struct sshbuf *b;
1066: const u_char *p;
1067: char *cp, *userstyle;
1068: size_t len;
1069: int r, fail = 0;
1070: u_char type;
1.1 provos 1071:
1.203 djm 1072: if ((b = sshbuf_from(data, datalen)) == NULL)
1.217 djm 1073: fatal_f("sshbuf_new");
1.203 djm 1074: if ((r = sshbuf_get_string_direct(b, &p, &len)) != 0)
1.217 djm 1075: fatal_fr(r, "parse sessionid");
1.3 markus 1076:
1.13 markus 1077: if ((session_id2 == NULL) ||
1078: (len != session_id2_len) ||
1.108 djm 1079: (timingsafe_bcmp(p, session_id2, session_id2_len) != 0))
1.1 provos 1080: fail++;
1.13 markus 1081:
1.183 markus 1082: if ((r = sshbuf_get_u8(b, &type)) != 0)
1.217 djm 1083: fatal_fr(r, "parse type");
1.183 markus 1084: if (type != SSH2_MSG_USERAUTH_REQUEST)
1.1 provos 1085: fail++;
1.183 markus 1086: if ((r = sshbuf_get_cstring(b, &cp, NULL)) != 0)
1.217 djm 1087: fatal_fr(r, "parse userstyle");
1.121 djm 1088: xasprintf(&userstyle, "%s%s%s", authctxt->user,
1089: authctxt->style ? ":" : "",
1090: authctxt->style ? authctxt->style : "");
1.183 markus 1091: if (strcmp(userstyle, cp) != 0) {
1092: logit("wrong user name passed to monitor: "
1093: "expected %s != %.100s", userstyle, cp);
1.1 provos 1094: fail++;
1095: }
1.121 djm 1096: free(userstyle);
1.183 markus 1097: free(cp);
1098: if ((r = sshbuf_skip_string(b)) != 0 || /* service */
1099: (r = sshbuf_get_cstring(b, &cp, NULL)) != 0)
1.217 djm 1100: fatal_fr(r, "parse method");
1.183 markus 1101: if (strcmp(cp, "hostbased") != 0)
1.1 provos 1102: fail++;
1.183 markus 1103: free(cp);
1104: if ((r = sshbuf_skip_string(b)) != 0 || /* pkalg */
1105: (r = sshbuf_skip_string(b)) != 0) /* pkblob */
1.217 djm 1106: fatal_fr(r, "parse pk");
1.1 provos 1107:
1108: /* verify client host, strip trailing dot if necessary */
1.183 markus 1109: if ((r = sshbuf_get_cstring(b, &cp, NULL)) != 0)
1.217 djm 1110: fatal_fr(r, "parse host");
1.183 markus 1111: if (((len = strlen(cp)) > 0) && cp[len - 1] == '.')
1112: cp[len - 1] = '\0';
1113: if (strcmp(cp, chost) != 0)
1.1 provos 1114: fail++;
1.183 markus 1115: free(cp);
1.1 provos 1116:
1117: /* verify client user */
1.183 markus 1118: if ((r = sshbuf_get_cstring(b, &cp, NULL)) != 0)
1.217 djm 1119: fatal_fr(r, "parse ruser");
1.183 markus 1120: if (strcmp(cp, cuser) != 0)
1.1 provos 1121: fail++;
1.183 markus 1122: free(cp);
1.1 provos 1123:
1.183 markus 1124: if (sshbuf_len(b) != 0)
1.1 provos 1125: fail++;
1.183 markus 1126: sshbuf_free(b);
1.1 provos 1127: return (fail == 0);
1128: }
1129:
1130: int
1.191 djm 1131: mm_answer_keyverify(struct ssh *ssh, int sock, struct sshbuf *m)
1.1 provos 1132: {
1.168 markus 1133: struct sshkey *key;
1.203 djm 1134: const u_char *signature, *data, *blob;
1135: char *sigalg = NULL, *fp = NULL;
1.169 markus 1136: size_t signaturelen, datalen, bloblen;
1.214 djm 1137: int r, ret, req_presence = 0, req_verify = 0, valid_data = 0;
1138: int encoded_ret;
1.202 djm 1139: struct sshkey_sig_details *sig_details = NULL;
1.1 provos 1140:
1.203 djm 1141: if ((r = sshbuf_get_string_direct(m, &blob, &bloblen)) != 0 ||
1142: (r = sshbuf_get_string_direct(m, &signature, &signaturelen)) != 0 ||
1143: (r = sshbuf_get_string_direct(m, &data, &datalen)) != 0 ||
1.176 djm 1144: (r = sshbuf_get_cstring(m, &sigalg, NULL)) != 0)
1.217 djm 1145: fatal_fr(r, "parse");
1.1 provos 1146:
1147: if (hostbased_cuser == NULL || hostbased_chost == NULL ||
1.8 mouring 1148: !monitor_allowed_key(blob, bloblen))
1.217 djm 1149: fatal_f("bad key, not previously allowed");
1.1 provos 1150:
1.177 djm 1151: /* Empty signature algorithm means NULL. */
1152: if (*sigalg == '\0') {
1153: free(sigalg);
1154: sigalg = NULL;
1155: }
1156:
1.169 markus 1157: /* XXX use sshkey_froms here; need to change key_blob, etc. */
1158: if ((r = sshkey_from_blob(blob, bloblen, &key)) != 0)
1.217 djm 1159: fatal_fr(r, "parse key");
1.1 provos 1160:
1161: switch (key_blobtype) {
1162: case MM_USERKEY:
1.222 djm 1163: valid_data = monitor_valid_userblob(ssh, data, datalen);
1.172 djm 1164: auth_method = "publickey";
1.1 provos 1165: break;
1166: case MM_HOSTKEY:
1167: valid_data = monitor_valid_hostbasedblob(data, datalen,
1168: hostbased_cuser, hostbased_chost);
1.172 djm 1169: auth_method = "hostbased";
1.1 provos 1170: break;
1171: default:
1172: valid_data = 0;
1173: break;
1174: }
1175: if (!valid_data)
1.223 djm 1176: fatal_f("bad %s signature data blob",
1177: key_blobtype == MM_USERKEY ? "userkey" :
1178: (key_blobtype == MM_HOSTKEY ? "hostkey" : "unknown"));
1.1 provos 1179:
1.203 djm 1180: if ((fp = sshkey_fingerprint(key, options.fingerprint_hash,
1181: SSH_FP_DEFAULT)) == NULL)
1.217 djm 1182: fatal_f("sshkey_fingerprint failed");
1.203 djm 1183:
1.169 markus 1184: ret = sshkey_verify(key, signature, signaturelen, data, datalen,
1.202 djm 1185: sigalg, ssh->compat, &sig_details);
1.228 ! djm 1186: debug3_f("%s %s signature %s%s%s", auth_method, sshkey_type(key),
1.201 djm 1187: (ret == 0) ? "verified" : "unverified",
1188: (ret != 0) ? ": " : "", (ret != 0) ? ssh_err(ret) : "");
1.203 djm 1189:
1190: if (ret == 0 && key_blobtype == MM_USERKEY && sig_details != NULL) {
1191: req_presence = (options.pubkey_auth_options &
1.204 djm 1192: PUBKEYAUTH_TOUCH_REQUIRED) ||
1193: !key_opts->no_require_user_presence;
1.203 djm 1194: if (req_presence &&
1195: (sig_details->sk_flags & SSH_SK_USER_PRESENCE_REQD) == 0) {
1196: error("public key %s %s signature for %s%s from %.128s "
1.208 naddy 1197: "port %d rejected: user presence "
1198: "(authenticator touch) requirement not met ",
1199: sshkey_type(key), fp,
1.214 djm 1200: authctxt->valid ? "" : "invalid user ",
1201: authctxt->user, ssh_remote_ipaddr(ssh),
1202: ssh_remote_port(ssh));
1203: ret = SSH_ERR_SIGNATURE_INVALID;
1204: }
1205: req_verify = (options.pubkey_auth_options &
1206: PUBKEYAUTH_VERIFY_REQUIRED) || key_opts->require_verify;
1207: if (req_verify &&
1208: (sig_details->sk_flags & SSH_SK_USER_VERIFICATION_REQD) == 0) {
1209: error("public key %s %s signature for %s%s from %.128s "
1210: "port %d rejected: user verification requirement "
1211: "not met ", sshkey_type(key), fp,
1.203 djm 1212: authctxt->valid ? "" : "invalid user ",
1213: authctxt->user, ssh_remote_ipaddr(ssh),
1214: ssh_remote_port(ssh));
1215: ret = SSH_ERR_SIGNATURE_INVALID;
1216: }
1217: }
1.172 djm 1218: auth2_record_key(authctxt, ret == 0, key);
1.136 djm 1219:
1.180 djm 1220: if (key_blobtype == MM_USERKEY)
1221: auth_activate_options(ssh, key_opts);
1.1 provos 1222: monitor_reset_key_state();
1.3 markus 1223:
1.169 markus 1224: sshbuf_reset(m);
1225:
1226: /* encode ret != 0 as positive integer, since we're sending u32 */
1227: encoded_ret = (ret != 0);
1.202 djm 1228: if ((r = sshbuf_put_u32(m, encoded_ret)) != 0 ||
1.205 djm 1229: (r = sshbuf_put_u8(m, sig_details != NULL)) != 0)
1.217 djm 1230: fatal_fr(r, "assemble");
1.202 djm 1231: if (sig_details != NULL) {
1232: if ((r = sshbuf_put_u32(m, sig_details->sk_counter)) != 0 ||
1233: (r = sshbuf_put_u8(m, sig_details->sk_flags)) != 0)
1.217 djm 1234: fatal_fr(r, "assemble sk");
1.202 djm 1235: }
1236: sshkey_sig_details_free(sig_details);
1.59 avsm 1237: mm_request_send(sock, MONITOR_ANS_KEYVERIFY, m);
1.203 djm 1238:
1239: free(sigalg);
1240: free(fp);
1241: sshkey_free(key);
1.1 provos 1242:
1.169 markus 1243: return ret == 0;
1.1 provos 1244: }
1245:
1.2 markus 1246: static void
1.191 djm 1247: mm_record_login(struct ssh *ssh, Session *s, struct passwd *pw)
1.1 provos 1248: {
1249: socklen_t fromlen;
1250: struct sockaddr_storage from;
1251:
1252: /*
1253: * Get IP address of client. If the connection is not a socket, let
1254: * the address be 0.0.0.0.
1255: */
1256: memset(&from, 0, sizeof(from));
1.24 stevesk 1257: fromlen = sizeof(from);
1.191 djm 1258: if (ssh_packet_connection_is_on_socket(ssh)) {
1259: if (getpeername(ssh_packet_get_connection_in(ssh),
1.198 deraadt 1260: (struct sockaddr *)&from, &fromlen) == -1) {
1.1 provos 1261: debug("getpeername: %.100s", strerror(errno));
1.50 markus 1262: cleanup_exit(255);
1.1 provos 1263: }
1264: }
1265: /* Record that there was a login on that tty from the remote host. */
1266: record_login(s->pid, s->tty, pw->pw_name, pw->pw_uid,
1.158 djm 1267: session_get_remote_name_or_ip(ssh, utmp_len, options.use_dns),
1.24 stevesk 1268: (struct sockaddr *)&from, fromlen);
1.1 provos 1269: }
1270:
1271: static void
1272: mm_session_close(Session *s)
1273: {
1.217 djm 1274: debug3_f("session %d pid %ld", s->self, (long)s->pid);
1.1 provos 1275: if (s->ttyfd != -1) {
1.217 djm 1276: debug3_f("tty %s ptyfd %d", s->tty, s->ptyfd);
1.1 provos 1277: session_pty_cleanup2(s);
1278: }
1.96 djm 1279: session_unused(s->self);
1.1 provos 1280: }
1281:
1282: int
1.191 djm 1283: mm_answer_pty(struct ssh *ssh, int sock, struct sshbuf *m)
1.1 provos 1284: {
1.11 mouring 1285: extern struct monitor *pmonitor;
1.1 provos 1286: Session *s;
1.183 markus 1287: int r, res, fd0;
1.1 provos 1288:
1.217 djm 1289: debug3_f("entering");
1.1 provos 1290:
1.183 markus 1291: sshbuf_reset(m);
1.1 provos 1292: s = session_new();
1293: if (s == NULL)
1294: goto error;
1295: s->authctxt = authctxt;
1296: s->pw = authctxt->pw;
1.11 mouring 1297: s->pid = pmonitor->m_pid;
1.1 provos 1298: res = pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty));
1299: if (res == 0)
1300: goto error;
1301: pty_setowner(authctxt->pw, s->tty);
1302:
1.183 markus 1303: if ((r = sshbuf_put_u32(m, 1)) != 0 ||
1304: (r = sshbuf_put_cstring(m, s->tty)) != 0)
1.217 djm 1305: fatal_fr(r, "assemble");
1.1 provos 1306:
1307: /* We need to trick ttyslot */
1308: if (dup2(s->ttyfd, 0) == -1)
1.217 djm 1309: fatal_f("dup2");
1.1 provos 1310:
1.191 djm 1311: mm_record_login(ssh, s, authctxt->pw);
1.1 provos 1312:
1313: /* Now we can close the file descriptor again */
1314: close(0);
1.61 dtucker 1315:
1316: /* send messages generated by record_login */
1.183 markus 1317: if ((r = sshbuf_put_stringb(m, loginmsg)) != 0)
1.217 djm 1318: fatal_fr(r, "assemble loginmsg");
1.183 markus 1319: sshbuf_reset(loginmsg);
1.61 dtucker 1320:
1321: mm_request_send(sock, MONITOR_ANS_PTY, m);
1322:
1.92 djm 1323: if (mm_send_fd(sock, s->ptyfd) == -1 ||
1324: mm_send_fd(sock, s->ttyfd) == -1)
1.217 djm 1325: fatal_f("send fds failed");
1.1 provos 1326:
1327: /* make sure nothing uses fd 0 */
1.198 deraadt 1328: if ((fd0 = open(_PATH_DEVNULL, O_RDONLY)) == -1)
1.217 djm 1329: fatal_f("open(/dev/null): %s", strerror(errno));
1.1 provos 1330: if (fd0 != 0)
1.217 djm 1331: error_f("fd0 %d != 0", fd0);
1.1 provos 1332:
1.212 deraadt 1333: /* slave side of pty is not needed */
1.1 provos 1334: close(s->ttyfd);
1335: s->ttyfd = s->ptyfd;
1336: /* no need to dup() because nobody closes ptyfd */
1337: s->ptymaster = s->ptyfd;
1338:
1.217 djm 1339: debug3_f("tty %s ptyfd %d", s->tty, s->ttyfd);
1.1 provos 1340:
1341: return (0);
1342:
1343: error:
1344: if (s != NULL)
1345: mm_session_close(s);
1.183 markus 1346: if ((r = sshbuf_put_u32(m, 0)) != 0)
1.217 djm 1347: fatal_fr(r, "assemble 0");
1.59 avsm 1348: mm_request_send(sock, MONITOR_ANS_PTY, m);
1.1 provos 1349: return (0);
1350: }
1351:
1352: int
1.191 djm 1353: mm_answer_pty_cleanup(struct ssh *ssh, int sock, struct sshbuf *m)
1.1 provos 1354: {
1355: Session *s;
1356: char *tty;
1.183 markus 1357: int r;
1.1 provos 1358:
1.217 djm 1359: debug3_f("entering");
1.1 provos 1360:
1.183 markus 1361: if ((r = sshbuf_get_cstring(m, &tty, NULL)) != 0)
1.217 djm 1362: fatal_fr(r, "parse tty");
1.1 provos 1363: if ((s = session_by_tty(tty)) != NULL)
1364: mm_session_close(s);
1.183 markus 1365: sshbuf_reset(m);
1.124 djm 1366: free(tty);
1.1 provos 1367: return (0);
1368: }
1369:
1370: int
1.191 djm 1371: mm_answer_term(struct ssh *ssh, int sock, struct sshbuf *req)
1.1 provos 1372: {
1.11 mouring 1373: extern struct monitor *pmonitor;
1.1 provos 1374: int res, status;
1375:
1.217 djm 1376: debug3_f("tearing down sessions");
1.1 provos 1377:
1378: /* The child is terminating */
1.173 djm 1379: session_destroy_all(ssh, &mm_session_close);
1.1 provos 1380:
1.11 mouring 1381: while (waitpid(pmonitor->m_pid, &status, 0) == -1)
1.9 markus 1382: if (errno != EINTR)
1383: exit(1);
1.1 provos 1384:
1385: res = WIFEXITED(status) ? WEXITSTATUS(status) : 1;
1386:
1387: /* Terminate process */
1.57 deraadt 1388: exit(res);
1.170 markus 1389: }
1390:
1391: void
1.191 djm 1392: monitor_clear_keystate(struct ssh *ssh, struct monitor *pmonitor)
1.170 markus 1393: {
1394: ssh_clear_newkeys(ssh, MODE_IN);
1395: ssh_clear_newkeys(ssh, MODE_OUT);
1396: sshbuf_free(child_state);
1397: child_state = NULL;
1.1 provos 1398: }
1399:
1400: void
1.191 djm 1401: monitor_apply_keystate(struct ssh *ssh, struct monitor *pmonitor)
1.1 provos 1402: {
1.139 markus 1403: struct kex *kex;
1404: int r;
1405:
1.217 djm 1406: debug3_f("packet_set_state");
1.139 markus 1407: if ((r = ssh_packet_set_state(ssh, child_state)) != 0)
1.217 djm 1408: fatal_fr(r, "packet_set_state");
1.139 markus 1409: sshbuf_free(child_state);
1410: child_state = NULL;
1.223 djm 1411: if ((kex = ssh->kex) == NULL)
1412: fatal_f("internal error: ssh->kex == NULL");
1413: if (session_id2_len != sshbuf_len(ssh->kex->session_id)) {
1414: fatal_f("incorrect session id length %zu (expected %u)",
1415: sshbuf_len(ssh->kex->session_id), session_id2_len);
1416: }
1417: if (memcmp(sshbuf_ptr(ssh->kex->session_id), session_id2,
1418: session_id2_len) != 0)
1419: fatal_f("session ID mismatch");
1420: /* XXX set callbacks */
1.147 djm 1421: #ifdef WITH_OPENSSL
1.223 djm 1422: kex->kex[KEX_DH_GRP1_SHA1] = kex_gen_server;
1423: kex->kex[KEX_DH_GRP14_SHA1] = kex_gen_server;
1424: kex->kex[KEX_DH_GRP14_SHA256] = kex_gen_server;
1425: kex->kex[KEX_DH_GRP16_SHA512] = kex_gen_server;
1426: kex->kex[KEX_DH_GRP18_SHA512] = kex_gen_server;
1427: kex->kex[KEX_DH_GEX_SHA1] = kexgex_server;
1428: kex->kex[KEX_DH_GEX_SHA256] = kexgex_server;
1429: kex->kex[KEX_ECDH_SHA2] = kex_gen_server;
1.147 djm 1430: #endif
1.223 djm 1431: kex->kex[KEX_C25519_SHA256] = kex_gen_server;
1432: kex->kex[KEX_KEM_SNTRUP761X25519_SHA512] = kex_gen_server;
1433: kex->load_host_public_key=&get_hostkey_public_by_type;
1434: kex->load_host_private_key=&get_hostkey_private_by_type;
1435: kex->host_key_index=&get_hostkey_index;
1436: kex->sign = sshd_hostkey_sign;
1.1 provos 1437: }
1438:
1.210 djm 1439: /* This function requires careful sanity checking */
1.1 provos 1440:
1441: void
1.192 djm 1442: mm_get_keystate(struct ssh *ssh, struct monitor *pmonitor)
1.1 provos 1443: {
1.217 djm 1444: debug3_f("Waiting for new keys");
1.1 provos 1445:
1.139 markus 1446: if ((child_state = sshbuf_new()) == NULL)
1.217 djm 1447: fatal_f("sshbuf_new failed");
1.139 markus 1448: mm_request_receive_expect(pmonitor->m_sendfd, MONITOR_REQ_KEYEXPORT,
1449: child_state);
1.217 djm 1450: debug3_f("GOT new keys");
1.1 provos 1451: }
1452:
1453:
1454: /* XXX */
1455:
1456: #define FD_CLOSEONEXEC(x) do { \
1.111 djm 1457: if (fcntl(x, F_SETFD, FD_CLOEXEC) == -1) \
1.1 provos 1458: fatal("fcntl(%d, F_SETFD)", x); \
1459: } while (0)
1460:
1.2 markus 1461: static void
1.114 djm 1462: monitor_openfds(struct monitor *mon, int do_logfds)
1.3 markus 1463: {
1.114 djm 1464: int pair[2];
1.171 markus 1465: #ifdef SO_ZEROIZE
1466: int on = 1;
1467: #endif
1.114 djm 1468:
1.1 provos 1469: if (socketpair(AF_UNIX, SOCK_STREAM, 0, pair) == -1)
1.217 djm 1470: fatal_f("socketpair: %s", strerror(errno));
1.171 markus 1471: #ifdef SO_ZEROIZE
1.198 deraadt 1472: if (setsockopt(pair[0], SOL_SOCKET, SO_ZEROIZE, &on, sizeof(on)) == -1)
1.171 markus 1473: error("setsockopt SO_ZEROIZE(0): %.100s", strerror(errno));
1.198 deraadt 1474: if (setsockopt(pair[1], SOL_SOCKET, SO_ZEROIZE, &on, sizeof(on)) == -1)
1.171 markus 1475: error("setsockopt SO_ZEROIZE(1): %.100s", strerror(errno));
1476: #endif
1.1 provos 1477: FD_CLOSEONEXEC(pair[0]);
1478: FD_CLOSEONEXEC(pair[1]);
1.114 djm 1479: mon->m_recvfd = pair[0];
1480: mon->m_sendfd = pair[1];
1481:
1482: if (do_logfds) {
1483: if (pipe(pair) == -1)
1.217 djm 1484: fatal_f("pipe: %s", strerror(errno));
1.114 djm 1485: FD_CLOSEONEXEC(pair[0]);
1486: FD_CLOSEONEXEC(pair[1]);
1487: mon->m_log_recvfd = pair[0];
1488: mon->m_log_sendfd = pair[1];
1489: } else
1490: mon->m_log_recvfd = mon->m_log_sendfd = -1;
1.1 provos 1491: }
1492:
1493: #define MM_MEMSIZE 65536
1494:
1495: struct monitor *
1496: monitor_init(void)
1497: {
1498: struct monitor *mon;
1499:
1.75 djm 1500: mon = xcalloc(1, sizeof(*mon));
1.114 djm 1501: monitor_openfds(mon, 1);
1.1 provos 1502:
1503: return mon;
1504: }
1505:
1506: void
1507: monitor_reinit(struct monitor *mon)
1508: {
1.114 djm 1509: monitor_openfds(mon, 0);
1.1 provos 1510: }
1.46 markus 1511:
1512: #ifdef GSSAPI
1513: int
1.191 djm 1514: mm_answer_gss_setup_ctx(struct ssh *ssh, int sock, struct sshbuf *m)
1.46 markus 1515: {
1.59 avsm 1516: gss_OID_desc goid;
1.46 markus 1517: OM_uint32 major;
1.183 markus 1518: size_t len;
1.184 djm 1519: u_char *p;
1.183 markus 1520: int r;
1.46 markus 1521:
1.164 djm 1522: if (!options.gss_authentication)
1.217 djm 1523: fatal_f("GSSAPI authentication not enabled");
1.164 djm 1524:
1.184 djm 1525: if ((r = sshbuf_get_string(m, &p, &len)) != 0)
1.217 djm 1526: fatal_fr(r, "parse");
1.184 djm 1527: goid.elements = p;
1.59 avsm 1528: goid.length = len;
1.46 markus 1529:
1.59 avsm 1530: major = ssh_gssapi_server_ctx(&gsscontext, &goid);
1.46 markus 1531:
1.124 djm 1532: free(goid.elements);
1.46 markus 1533:
1.183 markus 1534: sshbuf_reset(m);
1535: if ((r = sshbuf_put_u32(m, major)) != 0)
1.217 djm 1536: fatal_fr(r, "assemble");
1.46 markus 1537:
1.64 stevesk 1538: mm_request_send(sock, MONITOR_ANS_GSSSETUP, m);
1.46 markus 1539:
1540: /* Now we have a context, enable the step */
1541: monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 1);
1542:
1543: return (0);
1544: }
1545:
1546: int
1.191 djm 1547: mm_answer_gss_accept_ctx(struct ssh *ssh, int sock, struct sshbuf *m)
1.46 markus 1548: {
1549: gss_buffer_desc in;
1550: gss_buffer_desc out = GSS_C_EMPTY_BUFFER;
1.64 stevesk 1551: OM_uint32 major, minor;
1.46 markus 1552: OM_uint32 flags = 0; /* GSI needs this */
1.183 markus 1553: int r;
1.46 markus 1554:
1.164 djm 1555: if (!options.gss_authentication)
1.217 djm 1556: fatal_f("GSSAPI authentication not enabled");
1.164 djm 1557:
1.184 djm 1558: if ((r = ssh_gssapi_get_buffer_desc(m, &in)) != 0)
1.217 djm 1559: fatal_fr(r, "ssh_gssapi_get_buffer_desc");
1.46 markus 1560: major = ssh_gssapi_accept_ctx(gsscontext, &in, &out, &flags);
1.124 djm 1561: free(in.value);
1.46 markus 1562:
1.183 markus 1563: sshbuf_reset(m);
1564: if ((r = sshbuf_put_u32(m, major)) != 0 ||
1565: (r = sshbuf_put_string(m, out.value, out.length)) != 0 ||
1566: (r = sshbuf_put_u32(m, flags)) != 0)
1.217 djm 1567: fatal_fr(r, "assemble");
1.59 avsm 1568: mm_request_send(sock, MONITOR_ANS_GSSSTEP, m);
1.46 markus 1569:
1570: gss_release_buffer(&minor, &out);
1571:
1.64 stevesk 1572: if (major == GSS_S_COMPLETE) {
1.46 markus 1573: monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 0);
1574: monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
1.52 markus 1575: monitor_permit(mon_dispatch, MONITOR_REQ_GSSCHECKMIC, 1);
1.46 markus 1576: }
1577: return (0);
1578: }
1579:
1580: int
1.191 djm 1581: mm_answer_gss_checkmic(struct ssh *ssh, int sock, struct sshbuf *m)
1.52 markus 1582: {
1583: gss_buffer_desc gssbuf, mic;
1584: OM_uint32 ret;
1.184 djm 1585: int r;
1.54 djm 1586:
1.164 djm 1587: if (!options.gss_authentication)
1.217 djm 1588: fatal_f("GSSAPI authentication not enabled");
1.164 djm 1589:
1.184 djm 1590: if ((r = ssh_gssapi_get_buffer_desc(m, &gssbuf)) != 0 ||
1591: (r = ssh_gssapi_get_buffer_desc(m, &mic)) != 0)
1.217 djm 1592: fatal_fr(r, "ssh_gssapi_get_buffer_desc");
1.54 djm 1593:
1.52 markus 1594: ret = ssh_gssapi_checkmic(gsscontext, &gssbuf, &mic);
1.54 djm 1595:
1.124 djm 1596: free(gssbuf.value);
1597: free(mic.value);
1.54 djm 1598:
1.183 markus 1599: sshbuf_reset(m);
1600: if ((r = sshbuf_put_u32(m, ret)) != 0)
1.217 djm 1601: fatal_fr(r, "assemble");
1.54 djm 1602:
1.59 avsm 1603: mm_request_send(sock, MONITOR_ANS_GSSCHECKMIC, m);
1.54 djm 1604:
1.52 markus 1605: if (!GSS_ERROR(ret))
1606: monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
1.54 djm 1607:
1.52 markus 1608: return (0);
1609: }
1610:
1611: int
1.191 djm 1612: mm_answer_gss_userok(struct ssh *ssh, int sock, struct sshbuf *m)
1.46 markus 1613: {
1.184 djm 1614: int r, authenticated;
1.172 djm 1615: const char *displayname;
1.164 djm 1616:
1617: if (!options.gss_authentication)
1.217 djm 1618: fatal_f("GSSAPI authentication not enabled");
1.46 markus 1619:
1620: authenticated = authctxt->valid && ssh_gssapi_userok(authctxt->user);
1621:
1.183 markus 1622: sshbuf_reset(m);
1623: if ((r = sshbuf_put_u32(m, authenticated)) != 0)
1.217 djm 1624: fatal_fr(r, "assemble");
1.46 markus 1625:
1.217 djm 1626: debug3_f("sending result %d", authenticated);
1.59 avsm 1627: mm_request_send(sock, MONITOR_ANS_GSSUSEROK, m);
1.46 markus 1628:
1.64 stevesk 1629: auth_method = "gssapi-with-mic";
1.172 djm 1630:
1631: if ((displayname = ssh_gssapi_displayname()) != NULL)
1632: auth2_record_info(authctxt, "%s", displayname);
1.46 markus 1633:
1634: /* Monitor loop will terminate if authenticated */
1635: return (authenticated);
1636: }
1637: #endif /* GSSAPI */
1.100 djm 1638: