Annotation of src/usr.bin/ssh/monitor.c, Revision 1.193
1.193 ! djm 1: /* $OpenBSD: monitor.c,v 1.192 2019/01/19 21:43:56 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>
1.186 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"
1.189 djm 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[];
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_skeyquery(struct ssh *, int, struct sshbuf *);
109: int mm_answer_skeyrespond(struct ssh *, int, struct sshbuf *);
110: int mm_answer_keyallowed(struct ssh *, int, struct sshbuf *);
111: int mm_answer_keyverify(struct ssh *, int, struct sshbuf *);
112: int mm_answer_pty(struct ssh *, int, struct sshbuf *);
113: int mm_answer_pty_cleanup(struct ssh *, int, struct sshbuf *);
114: int mm_answer_term(struct ssh *, int, struct sshbuf *);
115: int mm_answer_rsa_keyallowed(struct ssh *, int, struct sshbuf *);
116: int mm_answer_rsa_challenge(struct ssh *, int, struct sshbuf *);
117: int mm_answer_rsa_response(struct ssh *, int, struct sshbuf *);
118: int mm_answer_sesskey(struct ssh *, int, struct sshbuf *);
119: int mm_answer_sessid(struct ssh *, int, struct sshbuf *);
1.1 provos 120:
1.46 markus 121: #ifdef GSSAPI
1.191 djm 122: int mm_answer_gss_setup_ctx(struct ssh *, int, struct sshbuf *);
123: int mm_answer_gss_accept_ctx(struct ssh *, int, struct sshbuf *);
124: int mm_answer_gss_userok(struct ssh *, int, struct sshbuf *);
125: int mm_answer_gss_checkmic(struct ssh *, int, struct sshbuf *);
1.46 markus 126: #endif
1.25 itojun 127:
1.1 provos 128: static Authctxt *authctxt;
1.132 markus 129:
1.1 provos 130: /* local state for key verify */
131: static u_char *key_blob = NULL;
1.183 markus 132: static size_t key_bloblen = 0;
1.1 provos 133: static int key_blobtype = MM_NOKEY;
1.180 djm 134: static struct sshauthopt *key_opts = NULL;
1.26 markus 135: static char *hostbased_cuser = NULL;
136: static char *hostbased_chost = NULL;
1.1 provos 137: static char *auth_method = "unknown";
1.119 djm 138: static char *auth_submethod = NULL;
1.44 markus 139: static u_int session_id2_len = 0;
1.13 markus 140: static u_char *session_id2 = NULL;
1.40 markus 141: static pid_t monitor_child_pid;
1.1 provos 142:
143: struct mon_table {
144: enum monitor_reqtype type;
145: int flags;
1.191 djm 146: int (*f)(struct ssh *, int, struct sshbuf *);
1.1 provos 147: };
148:
149: #define MON_ISAUTH 0x0004 /* Required for Authentication */
150: #define MON_AUTHDECIDE 0x0008 /* Decides Authentication */
151: #define MON_ONCE 0x0010 /* Disable after calling */
1.77 dtucker 152: #define MON_ALOG 0x0020 /* Log auth attempt without authenticating */
1.1 provos 153:
154: #define MON_AUTH (MON_ISAUTH|MON_AUTHDECIDE)
155:
156: #define MON_PERMIT 0x1000 /* Request is permitted */
157:
1.191 djm 158: static int monitor_read(struct ssh *, struct monitor *, struct mon_table *,
159: struct mon_table **);
160: static int monitor_read_log(struct monitor *);
161:
1.1 provos 162: struct mon_table mon_dispatch_proto20[] = {
1.132 markus 163: #ifdef WITH_OPENSSL
1.1 provos 164: {MONITOR_REQ_MODULI, MON_ONCE, mm_answer_moduli},
1.132 markus 165: #endif
1.1 provos 166: {MONITOR_REQ_SIGN, MON_ONCE, mm_answer_sign},
167: {MONITOR_REQ_PWNAM, MON_ONCE, mm_answer_pwnamallow},
168: {MONITOR_REQ_AUTHSERV, MON_ONCE, mm_answer_authserv},
1.10 djm 169: {MONITOR_REQ_AUTH2_READ_BANNER, MON_ONCE, mm_answer_auth2_read_banner},
1.1 provos 170: {MONITOR_REQ_AUTHPASSWORD, MON_AUTH, mm_answer_authpassword},
171: {MONITOR_REQ_BSDAUTHQUERY, MON_ISAUTH, mm_answer_bsdauthquery},
1.66 stevesk 172: {MONITOR_REQ_BSDAUTHRESPOND, MON_AUTH, mm_answer_bsdauthrespond},
1.1 provos 173: {MONITOR_REQ_KEYALLOWED, MON_ISAUTH, mm_answer_keyallowed},
174: {MONITOR_REQ_KEYVERIFY, MON_AUTH, mm_answer_keyverify},
1.46 markus 175: #ifdef GSSAPI
176: {MONITOR_REQ_GSSSETUP, MON_ISAUTH, mm_answer_gss_setup_ctx},
1.165 djm 177: {MONITOR_REQ_GSSSTEP, 0, mm_answer_gss_accept_ctx},
178: {MONITOR_REQ_GSSUSEROK, MON_ONCE|MON_AUTHDECIDE, mm_answer_gss_userok},
179: {MONITOR_REQ_GSSCHECKMIC, MON_ONCE, mm_answer_gss_checkmic},
1.46 markus 180: #endif
1.1 provos 181: {0, 0, NULL}
182: };
183:
184: struct mon_table mon_dispatch_postauth20[] = {
1.132 markus 185: #ifdef WITH_OPENSSL
1.1 provos 186: {MONITOR_REQ_MODULI, 0, mm_answer_moduli},
1.132 markus 187: #endif
1.1 provos 188: {MONITOR_REQ_SIGN, 0, mm_answer_sign},
189: {MONITOR_REQ_PTY, 0, mm_answer_pty},
190: {MONITOR_REQ_PTYCLEANUP, 0, mm_answer_pty_cleanup},
191: {MONITOR_REQ_TERM, 0, mm_answer_term},
192: {0, 0, NULL}
193: };
194:
195: struct mon_table *mon_dispatch;
196:
197: /* Specifies if a certain message is allowed at the moment */
198: static void
199: monitor_permit(struct mon_table *ent, enum monitor_reqtype type, int permit)
200: {
201: while (ent->f != NULL) {
202: if (ent->type == type) {
203: ent->flags &= ~MON_PERMIT;
204: ent->flags |= permit ? MON_PERMIT : 0;
205: return;
206: }
207: ent++;
208: }
209: }
210:
211: static void
212: monitor_permit_authentications(int permit)
213: {
214: struct mon_table *ent = mon_dispatch;
215:
216: while (ent->f != NULL) {
217: if (ent->flags & MON_AUTH) {
218: ent->flags &= ~MON_PERMIT;
219: ent->flags |= permit ? MON_PERMIT : 0;
220: }
221: ent++;
222: }
223: }
224:
1.50 markus 225: void
1.191 djm 226: monitor_child_preauth(struct ssh *ssh, struct monitor *pmonitor)
1.1 provos 227: {
228: struct mon_table *ent;
1.119 djm 229: int authenticated = 0, partial = 0;
1.1 provos 230:
231: debug3("preauth child monitor started");
232:
1.179 tb 233: if (pmonitor->m_recvfd >= 0)
234: close(pmonitor->m_recvfd);
235: if (pmonitor->m_log_sendfd >= 0)
236: close(pmonitor->m_log_sendfd);
1.114 djm 237: pmonitor->m_log_sendfd = pmonitor->m_recvfd = -1;
238:
1.191 djm 239: authctxt = (Authctxt *)ssh->authctxt;
1.50 markus 240: memset(authctxt, 0, sizeof(*authctxt));
1.180 djm 241: ssh->authctxt = authctxt;
1.50 markus 242:
1.162 markus 243: mon_dispatch = mon_dispatch_proto20;
244: /* Permit requests for moduli and signatures */
245: monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
246: monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
1.1 provos 247:
248: /* The first few requests do not require asynchronous access */
249: while (!authenticated) {
1.119 djm 250: partial = 0;
1.77 dtucker 251: auth_method = "unknown";
1.119 djm 252: auth_submethod = NULL;
1.172 djm 253: auth2_authctxt_reset_info(authctxt);
254:
1.191 djm 255: authenticated = (monitor_read(ssh, pmonitor,
256: mon_dispatch, &ent) == 1);
1.118 djm 257:
258: /* Special handling for multiple required authentications */
259: if (options.num_auth_methods != 0) {
260: if (authenticated &&
261: !auth2_update_methods_lists(authctxt,
1.122 markus 262: auth_method, auth_submethod)) {
1.118 djm 263: debug3("%s: method %s: partial", __func__,
264: auth_method);
265: authenticated = 0;
1.119 djm 266: partial = 1;
1.118 djm 267: }
268: }
269:
1.1 provos 270: if (authenticated) {
271: if (!(ent->flags & MON_AUTHDECIDE))
272: fatal("%s: unexpected authentication from %d",
1.14 markus 273: __func__, ent->type);
1.1 provos 274: if (authctxt->pw->pw_uid == 0 &&
1.180 djm 275: !auth_root_allowed(ssh, auth_method))
1.1 provos 276: authenticated = 0;
277: }
1.77 dtucker 278: if (ent->flags & (MON_AUTHDECIDE|MON_ALOG)) {
1.190 djm 279: auth_log(ssh, authenticated, partial,
1.125 djm 280: auth_method, auth_submethod);
1.150 djm 281: if (!partial && !authenticated)
1.1 provos 282: authctxt->failures++;
1.172 djm 283: if (authenticated || partial) {
284: auth2_update_session_info(authctxt,
285: auth_method, auth_submethod);
286: }
1.1 provos 287: }
288: }
289:
290: if (!authctxt->valid)
1.14 markus 291: fatal("%s: authenticated invalid user", __func__);
1.77 dtucker 292: if (strcmp(auth_method, "unknown") == 0)
293: fatal("%s: authentication method name unknown", __func__);
1.1 provos 294:
295: debug("%s: %s has been authenticated by privileged process",
1.14 markus 296: __func__, authctxt->user);
1.180 djm 297: ssh->authctxt = NULL;
1.167 djm 298: ssh_packet_set_log_preamble(ssh, "user %s", authctxt->user);
1.1 provos 299:
1.192 djm 300: mm_get_keystate(ssh, pmonitor);
1.120 markus 301:
302: /* Drain any buffered messages from the child */
303: while (pmonitor->m_log_recvfd != -1 && monitor_read_log(pmonitor) == 0)
304: ;
1.114 djm 305:
1.179 tb 306: if (pmonitor->m_recvfd >= 0)
307: close(pmonitor->m_recvfd);
308: if (pmonitor->m_log_sendfd >= 0)
309: close(pmonitor->m_log_sendfd);
1.114 djm 310: pmonitor->m_sendfd = pmonitor->m_log_recvfd = -1;
1.1 provos 311: }
312:
1.40 markus 313: static void
314: monitor_set_child_handler(pid_t pid)
315: {
316: monitor_child_pid = pid;
317: }
318:
319: static void
1.59 avsm 320: monitor_child_handler(int sig)
1.40 markus 321: {
1.59 avsm 322: kill(monitor_child_pid, sig);
1.40 markus 323: }
324:
1.1 provos 325: void
1.191 djm 326: monitor_child_postauth(struct ssh *ssh, struct monitor *pmonitor)
1.1 provos 327: {
1.114 djm 328: close(pmonitor->m_recvfd);
329: pmonitor->m_recvfd = -1;
330:
1.40 markus 331: monitor_set_child_handler(pmonitor->m_pid);
332: signal(SIGHUP, &monitor_child_handler);
333: signal(SIGTERM, &monitor_child_handler);
1.91 djm 334: signal(SIGINT, &monitor_child_handler);
1.40 markus 335:
1.162 markus 336: mon_dispatch = mon_dispatch_postauth20;
337:
338: /* Permit requests for moduli and signatures */
339: monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
340: monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
341: monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1);
1.1 provos 342:
1.180 djm 343: if (auth_opts->permit_pty_flag) {
1.1 provos 344: monitor_permit(mon_dispatch, MONITOR_REQ_PTY, 1);
345: monitor_permit(mon_dispatch, MONITOR_REQ_PTYCLEANUP, 1);
346: }
347:
348: for (;;)
1.191 djm 349: monitor_read(ssh, pmonitor, mon_dispatch, NULL);
1.1 provos 350: }
351:
1.114 djm 352: static int
353: monitor_read_log(struct monitor *pmonitor)
354: {
1.183 markus 355: struct sshbuf *logmsg;
1.114 djm 356: u_int len, level;
357: char *msg;
1.183 markus 358: u_char *p;
359: int r;
1.114 djm 360:
1.183 markus 361: if ((logmsg = sshbuf_new()) == NULL)
362: fatal("%s: sshbuf_new", __func__);
1.114 djm 363:
364: /* Read length */
1.183 markus 365: if ((r = sshbuf_reserve(logmsg, 4, &p)) != 0)
366: fatal("%s: reserve: %s", __func__, ssh_err(r));
367: if (atomicio(read, pmonitor->m_log_recvfd, p, 4) != 4) {
1.114 djm 368: if (errno == EPIPE) {
1.183 markus 369: sshbuf_free(logmsg);
1.114 djm 370: debug("%s: child log fd closed", __func__);
371: close(pmonitor->m_log_recvfd);
372: pmonitor->m_log_recvfd = -1;
373: return -1;
374: }
375: fatal("%s: log fd read: %s", __func__, strerror(errno));
376: }
1.183 markus 377: if ((r = sshbuf_get_u32(logmsg, &len)) != 0)
378: fatal("%s: get len: %s", __func__, ssh_err(r));
1.114 djm 379: if (len <= 4 || len > 8192)
380: fatal("%s: invalid log message length %u", __func__, len);
381:
382: /* Read severity, message */
1.183 markus 383: sshbuf_reset(logmsg);
384: if ((r = sshbuf_reserve(logmsg, len, &p)) != 0)
385: fatal("%s: reserve: %s", __func__, ssh_err(r));
386: if (atomicio(read, pmonitor->m_log_recvfd, p, len) != len)
1.114 djm 387: fatal("%s: log fd read: %s", __func__, strerror(errno));
1.183 markus 388: if ((r = sshbuf_get_u32(logmsg, &level)) != 0 ||
389: (r = sshbuf_get_cstring(logmsg, &msg, NULL)) != 0)
390: fatal("%s: decode: %s", __func__, ssh_err(r));
1.114 djm 391:
392: /* Log it */
393: if (log_level_name(level) == NULL)
394: fatal("%s: invalid log level %u (corrupted message?)",
395: __func__, level);
396: do_log2(level, "%s [preauth]", msg);
397:
1.183 markus 398: sshbuf_free(logmsg);
1.124 djm 399: free(msg);
1.114 djm 400:
401: return 0;
402: }
403:
1.191 djm 404: static int
405: monitor_read(struct ssh *ssh, struct monitor *pmonitor, struct mon_table *ent,
1.1 provos 406: struct mon_table **pent)
407: {
1.183 markus 408: struct sshbuf *m;
409: int r, ret;
1.1 provos 410: u_char type;
1.114 djm 411: struct pollfd pfd[2];
412:
413: for (;;) {
1.130 tedu 414: memset(&pfd, 0, sizeof(pfd));
1.114 djm 415: pfd[0].fd = pmonitor->m_sendfd;
416: pfd[0].events = POLLIN;
417: pfd[1].fd = pmonitor->m_log_recvfd;
418: pfd[1].events = pfd[1].fd == -1 ? 0 : POLLIN;
1.115 djm 419: if (poll(pfd, pfd[1].fd == -1 ? 1 : 2, -1) == -1) {
420: if (errno == EINTR || errno == EAGAIN)
421: continue;
1.114 djm 422: fatal("%s: poll: %s", __func__, strerror(errno));
1.115 djm 423: }
1.114 djm 424: if (pfd[1].revents) {
425: /*
426: * Drain all log messages before processing next
427: * monitor request.
428: */
429: monitor_read_log(pmonitor);
430: continue;
431: }
432: if (pfd[0].revents)
433: break; /* Continues below */
434: }
1.1 provos 435:
1.183 markus 436: if ((m = sshbuf_new()) == NULL)
437: fatal("%s: sshbuf_new", __func__);
1.1 provos 438:
1.183 markus 439: mm_request_receive(pmonitor->m_sendfd, m);
440: if ((r = sshbuf_get_u8(m, &type)) != 0)
441: fatal("%s: decode: %s", __func__, ssh_err(r));
1.1 provos 442:
1.14 markus 443: debug3("%s: checking request %d", __func__, type);
1.1 provos 444:
445: while (ent->f != NULL) {
446: if (ent->type == type)
447: break;
448: ent++;
449: }
450:
451: if (ent->f != NULL) {
452: if (!(ent->flags & MON_PERMIT))
1.14 markus 453: fatal("%s: unpermitted request %d", __func__,
1.1 provos 454: type);
1.191 djm 455: ret = (*ent->f)(ssh, pmonitor->m_sendfd, m);
1.183 markus 456: sshbuf_free(m);
1.1 provos 457:
458: /* The child may use this request only once, disable it */
459: if (ent->flags & MON_ONCE) {
1.14 markus 460: debug2("%s: %d used once, disabling now", __func__,
1.1 provos 461: type);
462: ent->flags &= ~MON_PERMIT;
463: }
464:
465: if (pent != NULL)
466: *pent = ent;
1.3 markus 467:
1.1 provos 468: return ret;
469: }
470:
1.14 markus 471: fatal("%s: unsupported request: %d", __func__, type);
1.1 provos 472:
473: /* NOTREACHED */
474: return (-1);
475: }
476:
477: /* allowed key state */
478: static int
479: monitor_allowed_key(u_char *blob, u_int bloblen)
480: {
481: /* make sure key is allowed */
482: if (key_blob == NULL || key_bloblen != bloblen ||
1.108 djm 483: timingsafe_bcmp(key_blob, blob, key_bloblen))
1.1 provos 484: return (0);
485: return (1);
486: }
487:
488: static void
489: monitor_reset_key_state(void)
490: {
491: /* reset state */
1.124 djm 492: free(key_blob);
493: free(hostbased_cuser);
494: free(hostbased_chost);
1.180 djm 495: sshauthopt_free(key_opts);
1.1 provos 496: key_blob = NULL;
497: key_bloblen = 0;
498: key_blobtype = MM_NOKEY;
1.180 djm 499: key_opts = NULL;
1.1 provos 500: hostbased_cuser = NULL;
501: hostbased_chost = NULL;
502: }
503:
1.132 markus 504: #ifdef WITH_OPENSSL
1.1 provos 505: int
1.191 djm 506: mm_answer_moduli(struct ssh *ssh, int sock, struct sshbuf *m)
1.1 provos 507: {
508: DH *dh;
1.187 djm 509: const BIGNUM *dh_p, *dh_g;
1.183 markus 510: int r;
511: u_int min, want, max;
1.1 provos 512:
1.183 markus 513: if ((r = sshbuf_get_u32(m, &min)) != 0 ||
514: (r = sshbuf_get_u32(m, &want)) != 0 ||
515: (r = sshbuf_get_u32(m, &max)) != 0)
516: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.1 provos 517:
518: debug3("%s: got parameters: %d %d %d",
1.14 markus 519: __func__, min, want, max);
1.1 provos 520: /* We need to check here, too, in case the child got corrupted */
521: if (max < min || want < min || max < want)
522: fatal("%s: bad parameters: %d %d %d",
1.14 markus 523: __func__, min, want, max);
1.1 provos 524:
1.183 markus 525: sshbuf_reset(m);
1.1 provos 526:
527: dh = choose_dh(min, want, max);
528: if (dh == NULL) {
1.183 markus 529: if ((r = sshbuf_put_u8(m, 0)) != 0)
530: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.1 provos 531: return (0);
532: } else {
533: /* Send first bignum */
1.187 djm 534: DH_get0_pqg(dh, &dh_p, NULL, &dh_g);
1.183 markus 535: if ((r = sshbuf_put_u8(m, 1)) != 0 ||
1.187 djm 536: (r = sshbuf_put_bignum2(m, dh_p)) != 0 ||
537: (r = sshbuf_put_bignum2(m, dh_g)) != 0)
1.183 markus 538: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.3 markus 539:
1.1 provos 540: DH_free(dh);
541: }
1.59 avsm 542: mm_request_send(sock, MONITOR_ANS_MODULI, m);
1.1 provos 543: return (0);
544: }
1.132 markus 545: #endif
1.1 provos 546:
547: int
1.191 djm 548: mm_answer_sign(struct ssh *ssh, int sock, struct sshbuf *m)
1.1 provos 549: {
1.138 djm 550: extern int auth_sock; /* XXX move to state struct? */
551: struct sshkey *key;
1.157 djm 552: struct sshbuf *sigbuf = NULL;
553: u_char *p = NULL, *signature = NULL;
554: char *alg = NULL;
1.155 markus 555: size_t datlen, siglen, alglen;
1.159 djm 556: int r, is_proof = 0;
1.185 markus 557: u_int keyid, compat;
1.145 djm 558: const char proof_req[] = "hostkeys-prove-00@openssh.com";
1.3 markus 559:
1.14 markus 560: debug3("%s", __func__);
1.1 provos 561:
1.138 djm 562: if ((r = sshbuf_get_u32(m, &keyid)) != 0 ||
1.155 markus 563: (r = sshbuf_get_string(m, &p, &datlen)) != 0 ||
1.185 markus 564: (r = sshbuf_get_cstring(m, &alg, &alglen)) != 0 ||
565: (r = sshbuf_get_u32(m, &compat)) != 0)
1.138 djm 566: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.159 djm 567: if (keyid > INT_MAX)
568: fatal("%s: invalid key ID", __func__);
1.1 provos 569:
1.69 djm 570: /*
1.110 djm 571: * Supported KEX types use SHA1 (20 bytes), SHA256 (32 bytes),
572: * SHA384 (48 bytes) and SHA512 (64 bytes).
1.144 djm 573: *
574: * Otherwise, verify the signature request is for a hostkey
575: * proof.
576: *
577: * XXX perform similar check for KEX signature requests too?
578: * it's not trivial, since what is signed is the hash, rather
579: * than the full kex structure...
1.69 djm 580: */
1.144 djm 581: if (datlen != 20 && datlen != 32 && datlen != 48 && datlen != 64) {
582: /*
583: * Construct expected hostkey proof and compare it to what
584: * the client sent us.
585: */
586: if (session_id2_len == 0) /* hostkeys is never first */
587: fatal("%s: bad data length: %zu", __func__, datlen);
588: if ((key = get_hostkey_public_by_index(keyid, ssh)) == NULL)
589: fatal("%s: no hostkey for index %d", __func__, keyid);
590: if ((sigbuf = sshbuf_new()) == NULL)
591: fatal("%s: sshbuf_new", __func__);
1.145 djm 592: if ((r = sshbuf_put_cstring(sigbuf, proof_req)) != 0 ||
593: (r = sshbuf_put_string(sigbuf, session_id2,
1.152 jsg 594: session_id2_len)) != 0 ||
1.144 djm 595: (r = sshkey_puts(key, sigbuf)) != 0)
596: fatal("%s: couldn't prepare private key "
597: "proof buffer: %s", __func__, ssh_err(r));
598: if (datlen != sshbuf_len(sigbuf) ||
599: memcmp(p, sshbuf_ptr(sigbuf), sshbuf_len(sigbuf)) != 0)
600: fatal("%s: bad data length: %zu, hostkey proof len %zu",
601: __func__, datlen, sshbuf_len(sigbuf));
602: sshbuf_free(sigbuf);
603: is_proof = 1;
604: }
1.1 provos 605:
1.13 markus 606: /* save session id, it will be passed on the first call */
607: if (session_id2_len == 0) {
608: session_id2_len = datlen;
609: session_id2 = xmalloc(session_id2_len);
610: memcpy(session_id2, p, session_id2_len);
611: }
612:
1.127 markus 613: if ((key = get_hostkey_by_index(keyid)) != NULL) {
1.155 markus 614: if ((r = sshkey_sign(key, &signature, &siglen, p, datlen, alg,
1.185 markus 615: compat)) != 0)
1.138 djm 616: fatal("%s: sshkey_sign failed: %s",
617: __func__, ssh_err(r));
1.144 djm 618: } else if ((key = get_hostkey_public_by_index(keyid, ssh)) != NULL &&
1.138 djm 619: auth_sock > 0) {
620: if ((r = ssh_agent_sign(auth_sock, key, &signature, &siglen,
1.185 markus 621: p, datlen, alg, compat)) != 0) {
1.138 djm 622: fatal("%s: ssh_agent_sign failed: %s",
623: __func__, ssh_err(r));
624: }
1.127 markus 625: } else
1.14 markus 626: fatal("%s: no hostkey from index %d", __func__, keyid);
1.1 provos 627:
1.144 djm 628: debug3("%s: %s signature %p(%zu)", __func__,
629: is_proof ? "KEX" : "hostkey proof", signature, siglen);
1.1 provos 630:
1.138 djm 631: sshbuf_reset(m);
632: if ((r = sshbuf_put_string(m, signature, siglen)) != 0)
633: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.1 provos 634:
1.157 djm 635: free(alg);
1.124 djm 636: free(p);
637: free(signature);
1.1 provos 638:
1.59 avsm 639: mm_request_send(sock, MONITOR_ANS_SIGN, m);
1.1 provos 640:
641: /* Turn on permissions for getpwnam */
642: monitor_permit(mon_dispatch, MONITOR_REQ_PWNAM, 1);
643:
644: return (0);
645: }
646:
647: /* Retrieves the password entry and also checks if the user is permitted */
648:
649: int
1.191 djm 650: mm_answer_pwnamallow(struct ssh *ssh, int sock, struct sshbuf *m)
1.1 provos 651: {
1.60 dtucker 652: char *username;
1.1 provos 653: struct passwd *pwent;
1.183 markus 654: int r, allowed = 0;
1.113 djm 655: u_int i;
1.3 markus 656:
1.14 markus 657: debug3("%s", __func__);
1.1 provos 658:
659: if (authctxt->attempt++ != 0)
1.14 markus 660: fatal("%s: multiple attempts for getpwnam", __func__);
1.1 provos 661:
1.183 markus 662: if ((r = sshbuf_get_cstring(m, &username, NULL)) != 0)
663: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.1 provos 664:
1.190 djm 665: pwent = getpwnamallow(ssh, username);
1.1 provos 666:
1.60 dtucker 667: authctxt->user = xstrdup(username);
668: setproctitle("%s [priv]", pwent ? username : "unknown");
1.124 djm 669: free(username);
1.1 provos 670:
1.183 markus 671: sshbuf_reset(m);
1.1 provos 672:
673: if (pwent == NULL) {
1.183 markus 674: if ((r = sshbuf_put_u8(m, 0)) != 0)
675: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.53 djm 676: authctxt->pw = fakepw();
1.1 provos 677: goto out;
678: }
679:
680: allowed = 1;
1.4 markus 681: authctxt->pw = pwent;
1.1 provos 682: authctxt->valid = 1;
683:
1.183 markus 684: /* XXX don't sent pwent to unpriv; send fake class/dir/shell too */
685: if ((r = sshbuf_put_u8(m, 1)) != 0 ||
686: (r = sshbuf_put_string(m, pwent, sizeof(*pwent))) != 0 ||
687: (r = sshbuf_put_cstring(m, pwent->pw_name)) != 0 ||
688: (r = sshbuf_put_cstring(m, "*")) != 0 ||
689: (r = sshbuf_put_cstring(m, pwent->pw_gecos)) != 0 ||
690: (r = sshbuf_put_cstring(m, pwent->pw_class)) != 0 ||
691: (r = sshbuf_put_cstring(m, pwent->pw_dir)) != 0 ||
692: (r = sshbuf_put_cstring(m, pwent->pw_shell)) != 0)
693: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.94 dtucker 694:
695: out:
1.167 djm 696: ssh_packet_set_log_preamble(ssh, "%suser %s",
697: authctxt->valid ? "authenticating" : "invalid ", authctxt->user);
1.183 markus 698: if ((r = sshbuf_put_string(m, &options, sizeof(options))) != 0)
699: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.112 djm 700:
701: #define M_CP_STROPT(x) do { \
1.183 markus 702: if (options.x != NULL) { \
703: if ((r = sshbuf_put_cstring(m, options.x)) != 0) \
704: fatal("%s: buffer error: %s", \
705: __func__, ssh_err(r)); \
706: } \
1.112 djm 707: } while (0)
1.113 djm 708: #define M_CP_STRARRAYOPT(x, nx) do { \
1.183 markus 709: for (i = 0; i < options.nx; i++) { \
710: if ((r = sshbuf_put_cstring(m, options.x[i])) != 0) \
711: fatal("%s: buffer error: %s", \
712: __func__, ssh_err(r)); \
713: } \
1.113 djm 714: } while (0)
1.112 djm 715: /* See comment in servconf.h */
716: COPY_MATCH_STRING_OPTS();
717: #undef M_CP_STROPT
1.113 djm 718: #undef M_CP_STRARRAYOPT
1.118 djm 719:
720: /* Create valid auth method lists */
1.162 markus 721: if (auth2_setup_methods_lists(authctxt) != 0) {
1.118 djm 722: /*
723: * The monitor will continue long enough to let the child
724: * run to it's packet_disconnect(), but it must not allow any
725: * authentication to succeed.
726: */
727: debug("%s: no valid authentication method lists", __func__);
728: }
729:
1.14 markus 730: debug3("%s: sending MONITOR_ANS_PWNAM: %d", __func__, allowed);
1.59 avsm 731: mm_request_send(sock, MONITOR_ANS_PWNAM, m);
1.1 provos 732:
1.162 markus 733: /* Allow service/style information on the auth context */
734: monitor_permit(mon_dispatch, MONITOR_REQ_AUTHSERV, 1);
735: monitor_permit(mon_dispatch, MONITOR_REQ_AUTH2_READ_BANNER, 1);
1.10 djm 736:
737: return (0);
738: }
739:
1.191 djm 740: int mm_answer_auth2_read_banner(struct ssh *ssh, int sock, struct sshbuf *m)
1.10 djm 741: {
742: char *banner;
1.183 markus 743: int r;
1.10 djm 744:
1.183 markus 745: sshbuf_reset(m);
1.10 djm 746: banner = auth2_read_banner();
1.183 markus 747: if ((r = sshbuf_put_cstring(m, banner != NULL ? banner : "")) != 0)
748: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.59 avsm 749: mm_request_send(sock, MONITOR_ANS_AUTH2_READ_BANNER, m);
1.124 djm 750: free(banner);
1.1 provos 751:
752: return (0);
753: }
754:
755: int
1.191 djm 756: mm_answer_authserv(struct ssh *ssh, int sock, struct sshbuf *m)
1.1 provos 757: {
1.183 markus 758: int r;
759:
1.1 provos 760: monitor_permit_authentications(1);
761:
1.183 markus 762: if ((r = sshbuf_get_cstring(m, &authctxt->service, NULL)) != 0 ||
763: (r = sshbuf_get_cstring(m, &authctxt->style, NULL)) != 0)
764: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.6 stevesk 765: debug3("%s: service=%s, style=%s",
1.14 markus 766: __func__, authctxt->service, authctxt->style);
1.6 stevesk 767:
1.1 provos 768: if (strlen(authctxt->style) == 0) {
1.124 djm 769: free(authctxt->style);
1.1 provos 770: authctxt->style = NULL;
771: }
772:
773: return (0);
774: }
775:
776: int
1.191 djm 777: mm_answer_authpassword(struct ssh *ssh, int sock, struct sshbuf *m)
1.1 provos 778: {
779: static int call_count;
780: char *passwd;
1.183 markus 781: int r, authenticated;
782: size_t plen;
1.1 provos 783:
1.164 djm 784: if (!options.password_authentication)
785: fatal("%s: password authentication not enabled", __func__);
1.183 markus 786: if ((r = sshbuf_get_cstring(m, &passwd, &plen)) != 0)
787: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.1 provos 788: /* Only authenticate if the context is valid */
1.12 markus 789: authenticated = options.password_authentication &&
1.180 djm 790: auth_password(ssh, passwd);
1.183 markus 791: explicit_bzero(passwd, plen);
1.124 djm 792: free(passwd);
1.1 provos 793:
1.183 markus 794: sshbuf_reset(m);
795: if ((r = sshbuf_put_u32(m, authenticated)) != 0)
796: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.1 provos 797:
1.14 markus 798: debug3("%s: sending result %d", __func__, authenticated);
1.59 avsm 799: mm_request_send(sock, MONITOR_ANS_AUTHPASSWORD, m);
1.1 provos 800:
801: call_count++;
802: if (plen == 0 && call_count == 1)
803: auth_method = "none";
804: else
805: auth_method = "password";
806:
807: /* Causes monitor loop to terminate if authenticated */
808: return (authenticated);
809: }
810:
811: int
1.191 djm 812: mm_answer_bsdauthquery(struct ssh *ssh, int sock, struct sshbuf *m)
1.1 provos 813: {
814: char *name, *infotxt;
1.183 markus 815: u_int numprompts, *echo_on, success;
1.1 provos 816: char **prompts;
1.183 markus 817: int r;
1.1 provos 818:
1.164 djm 819: if (!options.kbd_interactive_authentication)
820: fatal("%s: kbd-int authentication not enabled", __func__);
1.31 markus 821: success = bsdauth_query(authctxt, &name, &infotxt, &numprompts,
822: &prompts, &echo_on) < 0 ? 0 : 1;
1.1 provos 823:
1.183 markus 824: sshbuf_reset(m);
825: if ((r = sshbuf_put_u32(m, success)) != 0)
826: fatal("%s: buffer error: %s", __func__, ssh_err(r));
827: if (success) {
828: if ((r = sshbuf_put_cstring(m, prompts[0])) != 0)
829: fatal("%s: buffer error: %s", __func__, ssh_err(r));
830: }
1.1 provos 831:
1.31 markus 832: debug3("%s: sending challenge success: %u", __func__, success);
1.59 avsm 833: mm_request_send(sock, MONITOR_ANS_BSDAUTHQUERY, m);
1.1 provos 834:
1.31 markus 835: if (success) {
1.124 djm 836: free(name);
837: free(infotxt);
838: free(prompts);
839: free(echo_on);
1.1 provos 840: }
841:
842: return (0);
843: }
844:
845: int
1.191 djm 846: mm_answer_bsdauthrespond(struct ssh *ssh, int sock, struct sshbuf *m)
1.1 provos 847: {
848: char *response;
1.183 markus 849: int r, authok;
1.1 provos 850:
1.164 djm 851: if (!options.kbd_interactive_authentication)
852: fatal("%s: kbd-int authentication not enabled", __func__);
1.154 mmcc 853: if (authctxt->as == NULL)
1.14 markus 854: fatal("%s: no bsd auth session", __func__);
1.1 provos 855:
1.183 markus 856: if ((r = sshbuf_get_cstring(m, &response, NULL)) != 0)
857: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.12 markus 858: authok = options.challenge_response_authentication &&
859: auth_userresponse(authctxt->as, response, 0);
1.1 provos 860: authctxt->as = NULL;
1.14 markus 861: debug3("%s: <%s> = <%d>", __func__, response, authok);
1.124 djm 862: free(response);
1.1 provos 863:
1.183 markus 864: sshbuf_reset(m);
865: if ((r = sshbuf_put_u32(m, authok)) != 0)
866: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.1 provos 867:
1.14 markus 868: debug3("%s: sending authenticated: %d", __func__, authok);
1.59 avsm 869: mm_request_send(sock, MONITOR_ANS_BSDAUTHRESPOND, m);
1.1 provos 870:
1.162 markus 871: auth_method = "keyboard-interactive";
872: auth_submethod = "bsdauth";
1.1 provos 873:
874: return (authok != 0);
875: }
876:
1.188 djm 877: /*
878: * Check that the key type appears in the supplied pattern list, ignoring
879: * mismatches in the signature algorithm. (Signature algorithm checks are
880: * performed in the unprivileged authentication code).
881: * Returns 1 on success, 0 otherwise.
882: */
883: static int
884: key_base_type_match(const char *method, const struct sshkey *key,
885: const char *list)
886: {
887: char *s, *l, *ol = xstrdup(list);
888: int found = 0;
889:
890: l = ol;
891: for ((s = strsep(&l, ",")); s && *s != '\0'; (s = strsep(&l, ","))) {
892: if (sshkey_type_from_name(s) == key->type) {
893: found = 1;
894: break;
895: }
896: }
897: if (!found) {
898: error("%s key type %s is not in permitted list %s", method,
899: sshkey_ssh_name(key), list);
900: }
901:
902: free(ol);
903: return found;
904: }
905:
1.1 provos 906: int
1.191 djm 907: mm_answer_keyallowed(struct ssh *ssh, int sock, struct sshbuf *m)
1.1 provos 908: {
1.183 markus 909: struct sshkey *key = NULL;
1.26 markus 910: char *cuser, *chost;
1.183 markus 911: u_int pubkey_auth_attempt;
1.1 provos 912: enum mm_keytype type = 0;
1.180 djm 913: int r, allowed = 0;
914: struct sshauthopt *opts = NULL;
1.1 provos 915:
1.14 markus 916: debug3("%s entering", __func__);
1.183 markus 917: if ((r = sshbuf_get_u32(m, &type)) != 0 ||
918: (r = sshbuf_get_cstring(m, &cuser, NULL)) != 0 ||
919: (r = sshbuf_get_cstring(m, &chost, NULL)) != 0 ||
920: (r = sshkey_froms(m, &key)) != 0 ||
921: (r = sshbuf_get_u32(m, &pubkey_auth_attempt)) != 0)
922: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.1 provos 923:
1.14 markus 924: debug3("%s: key_from_blob: %p", __func__, key);
1.1 provos 925:
1.51 djm 926: if (key != NULL && authctxt->valid) {
1.137 djm 927: /* These should not make it past the privsep child */
1.185 markus 928: if (sshkey_type_plain(key->type) == KEY_RSA &&
1.137 djm 929: (datafellows & SSH_BUG_RSASIGMD5) != 0)
930: fatal("%s: passed a SSH_BUG_RSASIGMD5 key", __func__);
931:
1.63 deraadt 932: switch (type) {
1.1 provos 933: case MM_USERKEY:
1.77 dtucker 934: auth_method = "publickey";
1.180 djm 935: if (!options.pubkey_authentication)
936: break;
937: if (auth2_key_already_used(authctxt, key))
938: break;
1.188 djm 939: if (!key_base_type_match(auth_method, key,
940: options.pubkey_key_types))
1.180 djm 941: break;
942: allowed = user_key_allowed(ssh, authctxt->pw, key,
943: pubkey_auth_attempt, &opts);
1.1 provos 944: break;
945: case MM_HOSTKEY:
1.180 djm 946: auth_method = "hostbased";
947: if (!options.hostbased_authentication)
948: break;
949: if (auth2_key_already_used(authctxt, key))
950: break;
1.188 djm 951: if (!key_base_type_match(auth_method, key,
952: options.hostbased_key_types))
1.180 djm 953: break;
1.192 djm 954: allowed = hostbased_key_allowed(ssh, authctxt->pw,
1.1 provos 955: cuser, chost, key);
1.172 djm 956: auth2_record_info(authctxt,
1.126 djm 957: "client user \"%.100s\", client host \"%.100s\"",
958: cuser, chost);
1.1 provos 959: break;
960: default:
1.14 markus 961: fatal("%s: unknown key type %d", __func__, type);
1.1 provos 962: break;
963: }
1.33 markus 964: }
1.161 djm 965:
1.180 djm 966: debug3("%s: %s authentication%s: %s key is %s", __func__,
967: auth_method, pubkey_auth_attempt ? "" : " test",
968: (key == NULL || !authctxt->valid) ? "invalid" : sshkey_type(key),
969: allowed ? "allowed" : "not allowed");
1.161 djm 970:
1.172 djm 971: auth2_record_key(authctxt, 0, key);
1.1 provos 972:
973: /* clear temporarily storage (used by verify) */
974: monitor_reset_key_state();
975:
976: if (allowed) {
977: /* Save temporarily for comparison in verify */
1.183 markus 978: if ((r = sshkey_to_blob(key, &key_blob, &key_bloblen)) != 0)
979: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.1 provos 980: key_blobtype = type;
1.180 djm 981: key_opts = opts;
1.1 provos 982: hostbased_cuser = cuser;
983: hostbased_chost = chost;
1.72 djm 984: } else {
1.77 dtucker 985: /* Log failed attempt */
1.190 djm 986: auth_log(ssh, 0, 0, auth_method, NULL);
1.124 djm 987: free(cuser);
988: free(chost);
1.1 provos 989: }
1.183 markus 990: sshkey_free(key);
1.1 provos 991:
1.183 markus 992: sshbuf_reset(m);
993: if ((r = sshbuf_put_u32(m, allowed)) != 0)
994: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.180 djm 995: if (opts != NULL && (r = sshauthopt_serialise(opts, m, 1)) != 0)
996: fatal("%s: sshauthopt_serialise: %s", __func__, ssh_err(r));
997: mm_request_send(sock, MONITOR_ANS_KEYALLOWED, m);
1.1 provos 998:
1.180 djm 999: if (!allowed)
1000: sshauthopt_free(opts);
1.1 provos 1001:
1002: return (0);
1003: }
1004:
1005: static int
1006: monitor_valid_userblob(u_char *data, u_int datalen)
1007: {
1.183 markus 1008: struct sshbuf *b;
1009: const u_char *p;
1.159 djm 1010: char *userstyle, *cp;
1.183 markus 1011: size_t len;
1012: u_char type;
1013: int r, fail = 0;
1.1 provos 1014:
1.183 markus 1015: if ((b = sshbuf_new()) == NULL)
1016: fatal("%s: sshbuf_new", __func__);
1017: if ((r = sshbuf_put(b, data, datalen)) != 0)
1018: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.3 markus 1019:
1.1 provos 1020: if (datafellows & SSH_OLD_SESSIONID) {
1.183 markus 1021: p = sshbuf_ptr(b);
1022: len = sshbuf_len(b);
1.13 markus 1023: if ((session_id2 == NULL) ||
1024: (len < session_id2_len) ||
1.108 djm 1025: (timingsafe_bcmp(p, session_id2, session_id2_len) != 0))
1.13 markus 1026: fail++;
1.183 markus 1027: if ((r = sshbuf_consume(b, session_id2_len)) != 0)
1028: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.1 provos 1029: } else {
1.183 markus 1030: if ((r = sshbuf_get_string_direct(b, &p, &len)) != 0)
1031: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.13 markus 1032: if ((session_id2 == NULL) ||
1033: (len != session_id2_len) ||
1.108 djm 1034: (timingsafe_bcmp(p, session_id2, session_id2_len) != 0))
1.1 provos 1035: fail++;
1036: }
1.183 markus 1037: if ((r = sshbuf_get_u8(b, &type)) != 0)
1038: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1039: if (type != SSH2_MSG_USERAUTH_REQUEST)
1.1 provos 1040: fail++;
1.183 markus 1041: if ((r = sshbuf_get_cstring(b, &cp, NULL)) != 0)
1042: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.121 djm 1043: xasprintf(&userstyle, "%s%s%s", authctxt->user,
1044: authctxt->style ? ":" : "",
1045: authctxt->style ? authctxt->style : "");
1.159 djm 1046: if (strcmp(userstyle, cp) != 0) {
1047: logit("wrong user name passed to monitor: "
1048: "expected %s != %.100s", userstyle, cp);
1.1 provos 1049: fail++;
1050: }
1.124 djm 1051: free(userstyle);
1.159 djm 1052: free(cp);
1.183 markus 1053: if ((r = sshbuf_skip_string(b)) != 0 || /* service */
1054: (r = sshbuf_get_cstring(b, &cp, NULL)) != 0)
1055: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.178 djm 1056: if (strcmp("publickey", cp) != 0)
1057: fail++;
1058: free(cp);
1.183 markus 1059: if ((r = sshbuf_get_u8(b, &type)) != 0)
1060: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1061: if (type == 0)
1.178 djm 1062: fail++;
1.183 markus 1063: if ((r = sshbuf_skip_string(b)) != 0 || /* pkalg */
1064: (r = sshbuf_skip_string(b)) != 0) /* pkblob */
1065: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1066: if (sshbuf_len(b) != 0)
1.1 provos 1067: fail++;
1.183 markus 1068: sshbuf_free(b);
1.1 provos 1069: return (fail == 0);
1070: }
1071:
1072: static int
1.26 markus 1073: monitor_valid_hostbasedblob(u_char *data, u_int datalen, char *cuser,
1074: char *chost)
1.1 provos 1075: {
1.183 markus 1076: struct sshbuf *b;
1077: const u_char *p;
1078: char *cp, *userstyle;
1079: size_t len;
1080: int r, fail = 0;
1081: u_char type;
1.1 provos 1082:
1.183 markus 1083: if ((b = sshbuf_new()) == NULL)
1084: fatal("%s: sshbuf_new", __func__);
1085: if ((r = sshbuf_put(b, data, datalen)) != 0 ||
1086: (r = sshbuf_get_string_direct(b, &p, &len)) != 0)
1087: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.3 markus 1088:
1.13 markus 1089: if ((session_id2 == NULL) ||
1090: (len != session_id2_len) ||
1.108 djm 1091: (timingsafe_bcmp(p, session_id2, session_id2_len) != 0))
1.1 provos 1092: fail++;
1.13 markus 1093:
1.183 markus 1094: if ((r = sshbuf_get_u8(b, &type)) != 0)
1095: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1096: if (type != SSH2_MSG_USERAUTH_REQUEST)
1.1 provos 1097: fail++;
1.183 markus 1098: if ((r = sshbuf_get_cstring(b, &cp, NULL)) != 0)
1099: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.121 djm 1100: xasprintf(&userstyle, "%s%s%s", authctxt->user,
1101: authctxt->style ? ":" : "",
1102: authctxt->style ? authctxt->style : "");
1.183 markus 1103: if (strcmp(userstyle, cp) != 0) {
1104: logit("wrong user name passed to monitor: "
1105: "expected %s != %.100s", userstyle, cp);
1.1 provos 1106: fail++;
1107: }
1.121 djm 1108: free(userstyle);
1.183 markus 1109: free(cp);
1110: if ((r = sshbuf_skip_string(b)) != 0 || /* service */
1111: (r = sshbuf_get_cstring(b, &cp, NULL)) != 0)
1112: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1113: if (strcmp(cp, "hostbased") != 0)
1.1 provos 1114: fail++;
1.183 markus 1115: free(cp);
1116: if ((r = sshbuf_skip_string(b)) != 0 || /* pkalg */
1117: (r = sshbuf_skip_string(b)) != 0) /* pkblob */
1118: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.1 provos 1119:
1120: /* verify client host, strip trailing dot if necessary */
1.183 markus 1121: if ((r = sshbuf_get_cstring(b, &cp, NULL)) != 0)
1122: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1123: if (((len = strlen(cp)) > 0) && cp[len - 1] == '.')
1124: cp[len - 1] = '\0';
1125: if (strcmp(cp, chost) != 0)
1.1 provos 1126: fail++;
1.183 markus 1127: free(cp);
1.1 provos 1128:
1129: /* verify client user */
1.183 markus 1130: if ((r = sshbuf_get_cstring(b, &cp, NULL)) != 0)
1131: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1132: if (strcmp(cp, cuser) != 0)
1.1 provos 1133: fail++;
1.183 markus 1134: free(cp);
1.1 provos 1135:
1.183 markus 1136: if (sshbuf_len(b) != 0)
1.1 provos 1137: fail++;
1.183 markus 1138: sshbuf_free(b);
1.1 provos 1139: return (fail == 0);
1140: }
1141:
1142: int
1.191 djm 1143: mm_answer_keyverify(struct ssh *ssh, int sock, struct sshbuf *m)
1.1 provos 1144: {
1.168 markus 1145: struct sshkey *key;
1.1 provos 1146: u_char *signature, *data, *blob;
1.176 djm 1147: char *sigalg;
1.169 markus 1148: size_t signaturelen, datalen, bloblen;
1149: int r, ret, valid_data = 0, encoded_ret;
1.1 provos 1150:
1.169 markus 1151: if ((r = sshbuf_get_string(m, &blob, &bloblen)) != 0 ||
1152: (r = sshbuf_get_string(m, &signature, &signaturelen)) != 0 ||
1.176 djm 1153: (r = sshbuf_get_string(m, &data, &datalen)) != 0 ||
1154: (r = sshbuf_get_cstring(m, &sigalg, NULL)) != 0)
1.169 markus 1155: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.1 provos 1156:
1157: if (hostbased_cuser == NULL || hostbased_chost == NULL ||
1.8 mouring 1158: !monitor_allowed_key(blob, bloblen))
1.14 markus 1159: fatal("%s: bad key, not previously allowed", __func__);
1.1 provos 1160:
1.177 djm 1161: /* Empty signature algorithm means NULL. */
1162: if (*sigalg == '\0') {
1163: free(sigalg);
1164: sigalg = NULL;
1165: }
1166:
1.169 markus 1167: /* XXX use sshkey_froms here; need to change key_blob, etc. */
1168: if ((r = sshkey_from_blob(blob, bloblen, &key)) != 0)
1169: fatal("%s: bad public key blob: %s", __func__, ssh_err(r));
1.1 provos 1170:
1171: switch (key_blobtype) {
1172: case MM_USERKEY:
1173: valid_data = monitor_valid_userblob(data, datalen);
1.172 djm 1174: auth_method = "publickey";
1.1 provos 1175: break;
1176: case MM_HOSTKEY:
1177: valid_data = monitor_valid_hostbasedblob(data, datalen,
1178: hostbased_cuser, hostbased_chost);
1.172 djm 1179: auth_method = "hostbased";
1.1 provos 1180: break;
1181: default:
1182: valid_data = 0;
1183: break;
1184: }
1185: if (!valid_data)
1.14 markus 1186: fatal("%s: bad signature data blob", __func__);
1.1 provos 1187:
1.169 markus 1188: ret = sshkey_verify(key, signature, signaturelen, data, datalen,
1.191 djm 1189: sigalg, ssh->compat);
1.172 djm 1190: debug3("%s: %s %p signature %s", __func__, auth_method, key,
1191: (ret == 0) ? "verified" : "unverified");
1192: auth2_record_key(authctxt, ret == 0, key);
1.136 djm 1193:
1.124 djm 1194: free(blob);
1195: free(signature);
1196: free(data);
1.177 djm 1197: free(sigalg);
1.1 provos 1198:
1.180 djm 1199: if (key_blobtype == MM_USERKEY)
1200: auth_activate_options(ssh, key_opts);
1.1 provos 1201: monitor_reset_key_state();
1.3 markus 1202:
1.172 djm 1203: sshkey_free(key);
1.169 markus 1204: sshbuf_reset(m);
1205:
1206: /* encode ret != 0 as positive integer, since we're sending u32 */
1207: encoded_ret = (ret != 0);
1208: if ((r = sshbuf_put_u32(m, encoded_ret)) != 0)
1209: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.59 avsm 1210: mm_request_send(sock, MONITOR_ANS_KEYVERIFY, m);
1.1 provos 1211:
1.169 markus 1212: return ret == 0;
1.1 provos 1213: }
1214:
1.2 markus 1215: static void
1.191 djm 1216: mm_record_login(struct ssh *ssh, Session *s, struct passwd *pw)
1.1 provos 1217: {
1218: socklen_t fromlen;
1219: struct sockaddr_storage from;
1220:
1221: /*
1222: * Get IP address of client. If the connection is not a socket, let
1223: * the address be 0.0.0.0.
1224: */
1225: memset(&from, 0, sizeof(from));
1.24 stevesk 1226: fromlen = sizeof(from);
1.191 djm 1227: if (ssh_packet_connection_is_on_socket(ssh)) {
1228: if (getpeername(ssh_packet_get_connection_in(ssh),
1.74 deraadt 1229: (struct sockaddr *)&from, &fromlen) < 0) {
1.1 provos 1230: debug("getpeername: %.100s", strerror(errno));
1.50 markus 1231: cleanup_exit(255);
1.1 provos 1232: }
1233: }
1234: /* Record that there was a login on that tty from the remote host. */
1235: record_login(s->pid, s->tty, pw->pw_name, pw->pw_uid,
1.158 djm 1236: session_get_remote_name_or_ip(ssh, utmp_len, options.use_dns),
1.24 stevesk 1237: (struct sockaddr *)&from, fromlen);
1.1 provos 1238: }
1239:
1240: static void
1241: mm_session_close(Session *s)
1242: {
1.41 djm 1243: debug3("%s: session %d pid %ld", __func__, s->self, (long)s->pid);
1.1 provos 1244: if (s->ttyfd != -1) {
1.86 stevesk 1245: debug3("%s: tty %s ptyfd %d", __func__, s->tty, s->ptyfd);
1.1 provos 1246: session_pty_cleanup2(s);
1247: }
1.96 djm 1248: session_unused(s->self);
1.1 provos 1249: }
1250:
1251: int
1.191 djm 1252: mm_answer_pty(struct ssh *ssh, int sock, struct sshbuf *m)
1.1 provos 1253: {
1.11 mouring 1254: extern struct monitor *pmonitor;
1.1 provos 1255: Session *s;
1.183 markus 1256: int r, res, fd0;
1.1 provos 1257:
1.14 markus 1258: debug3("%s entering", __func__);
1.1 provos 1259:
1.183 markus 1260: sshbuf_reset(m);
1.1 provos 1261: s = session_new();
1262: if (s == NULL)
1263: goto error;
1264: s->authctxt = authctxt;
1265: s->pw = authctxt->pw;
1.11 mouring 1266: s->pid = pmonitor->m_pid;
1.1 provos 1267: res = pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty));
1268: if (res == 0)
1269: goto error;
1270: pty_setowner(authctxt->pw, s->tty);
1271:
1.183 markus 1272: if ((r = sshbuf_put_u32(m, 1)) != 0 ||
1273: (r = sshbuf_put_cstring(m, s->tty)) != 0)
1274: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.1 provos 1275:
1276: /* We need to trick ttyslot */
1277: if (dup2(s->ttyfd, 0) == -1)
1.14 markus 1278: fatal("%s: dup2", __func__);
1.1 provos 1279:
1.191 djm 1280: mm_record_login(ssh, s, authctxt->pw);
1.1 provos 1281:
1282: /* Now we can close the file descriptor again */
1283: close(0);
1.61 dtucker 1284:
1285: /* send messages generated by record_login */
1.183 markus 1286: if ((r = sshbuf_put_stringb(m, loginmsg)) != 0)
1287: fatal("%s: put login message: %s", __func__, ssh_err(r));
1288: sshbuf_reset(loginmsg);
1.61 dtucker 1289:
1290: mm_request_send(sock, MONITOR_ANS_PTY, m);
1291:
1.92 djm 1292: if (mm_send_fd(sock, s->ptyfd) == -1 ||
1293: mm_send_fd(sock, s->ttyfd) == -1)
1294: fatal("%s: send fds failed", __func__);
1.1 provos 1295:
1296: /* make sure nothing uses fd 0 */
1297: if ((fd0 = open(_PATH_DEVNULL, O_RDONLY)) < 0)
1.14 markus 1298: fatal("%s: open(/dev/null): %s", __func__, strerror(errno));
1.1 provos 1299: if (fd0 != 0)
1.14 markus 1300: error("%s: fd0 %d != 0", __func__, fd0);
1.1 provos 1301:
1302: /* slave is not needed */
1303: close(s->ttyfd);
1304: s->ttyfd = s->ptyfd;
1305: /* no need to dup() because nobody closes ptyfd */
1306: s->ptymaster = s->ptyfd;
1307:
1.86 stevesk 1308: debug3("%s: tty %s ptyfd %d", __func__, s->tty, s->ttyfd);
1.1 provos 1309:
1310: return (0);
1311:
1312: error:
1313: if (s != NULL)
1314: mm_session_close(s);
1.183 markus 1315: if ((r = sshbuf_put_u32(m, 0)) != 0)
1316: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.59 avsm 1317: mm_request_send(sock, MONITOR_ANS_PTY, m);
1.1 provos 1318: return (0);
1319: }
1320:
1321: int
1.191 djm 1322: mm_answer_pty_cleanup(struct ssh *ssh, int sock, struct sshbuf *m)
1.1 provos 1323: {
1324: Session *s;
1325: char *tty;
1.183 markus 1326: int r;
1.1 provos 1327:
1.14 markus 1328: debug3("%s entering", __func__);
1.1 provos 1329:
1.183 markus 1330: if ((r = sshbuf_get_cstring(m, &tty, NULL)) != 0)
1331: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.1 provos 1332: if ((s = session_by_tty(tty)) != NULL)
1333: mm_session_close(s);
1.183 markus 1334: sshbuf_reset(m);
1.124 djm 1335: free(tty);
1.1 provos 1336: return (0);
1337: }
1338:
1339: int
1.191 djm 1340: mm_answer_term(struct ssh *ssh, int sock, struct sshbuf *req)
1.1 provos 1341: {
1.11 mouring 1342: extern struct monitor *pmonitor;
1.1 provos 1343: int res, status;
1344:
1.14 markus 1345: debug3("%s: tearing down sessions", __func__);
1.1 provos 1346:
1347: /* The child is terminating */
1.173 djm 1348: session_destroy_all(ssh, &mm_session_close);
1.1 provos 1349:
1.11 mouring 1350: while (waitpid(pmonitor->m_pid, &status, 0) == -1)
1.9 markus 1351: if (errno != EINTR)
1352: exit(1);
1.1 provos 1353:
1354: res = WIFEXITED(status) ? WEXITSTATUS(status) : 1;
1355:
1356: /* Terminate process */
1.57 deraadt 1357: exit(res);
1.170 markus 1358: }
1359:
1360: void
1.191 djm 1361: monitor_clear_keystate(struct ssh *ssh, struct monitor *pmonitor)
1.170 markus 1362: {
1363: ssh_clear_newkeys(ssh, MODE_IN);
1364: ssh_clear_newkeys(ssh, MODE_OUT);
1365: sshbuf_free(child_state);
1366: child_state = NULL;
1.1 provos 1367: }
1368:
1369: void
1.191 djm 1370: monitor_apply_keystate(struct ssh *ssh, struct monitor *pmonitor)
1.1 provos 1371: {
1.139 markus 1372: struct kex *kex;
1373: int r;
1374:
1375: debug3("%s: packet_set_state", __func__);
1376: if ((r = ssh_packet_set_state(ssh, child_state)) != 0)
1377: fatal("%s: packet_set_state: %s", __func__, ssh_err(r));
1378: sshbuf_free(child_state);
1379: child_state = NULL;
1380:
1.154 mmcc 1381: if ((kex = ssh->kex) != NULL) {
1.139 markus 1382: /* XXX set callbacks */
1.147 djm 1383: #ifdef WITH_OPENSSL
1.139 markus 1384: kex->kex[KEX_DH_GRP1_SHA1] = kexdh_server;
1385: kex->kex[KEX_DH_GRP14_SHA1] = kexdh_server;
1.160 djm 1386: kex->kex[KEX_DH_GRP14_SHA256] = kexdh_server;
1387: kex->kex[KEX_DH_GRP16_SHA512] = kexdh_server;
1388: kex->kex[KEX_DH_GRP18_SHA512] = kexdh_server;
1.139 markus 1389: kex->kex[KEX_DH_GEX_SHA1] = kexgex_server;
1390: kex->kex[KEX_DH_GEX_SHA256] = kexgex_server;
1391: kex->kex[KEX_ECDH_SHA2] = kexecdh_server;
1.147 djm 1392: #endif
1.139 markus 1393: kex->kex[KEX_C25519_SHA256] = kexc25519_server;
1.193 ! djm 1394: kex->kex[KEX_KEM_SNTRUP4591761X25519_SHA512] = kex_kem_server;
1.139 markus 1395: kex->load_host_public_key=&get_hostkey_public_by_type;
1396: kex->load_host_private_key=&get_hostkey_private_by_type;
1397: kex->host_key_index=&get_hostkey_index;
1398: kex->sign = sshd_hostkey_sign;
1399: }
1.1 provos 1400: }
1401:
1402: /* This function requries careful sanity checking */
1403:
1404: void
1.192 djm 1405: mm_get_keystate(struct ssh *ssh, struct monitor *pmonitor)
1.1 provos 1406: {
1.14 markus 1407: debug3("%s: Waiting for new keys", __func__);
1.1 provos 1408:
1.139 markus 1409: if ((child_state = sshbuf_new()) == NULL)
1410: fatal("%s: sshbuf_new failed", __func__);
1411: mm_request_receive_expect(pmonitor->m_sendfd, MONITOR_REQ_KEYEXPORT,
1412: child_state);
1413: debug3("%s: GOT new keys", __func__);
1.1 provos 1414: }
1415:
1416:
1417: /* XXX */
1418:
1419: #define FD_CLOSEONEXEC(x) do { \
1.111 djm 1420: if (fcntl(x, F_SETFD, FD_CLOEXEC) == -1) \
1.1 provos 1421: fatal("fcntl(%d, F_SETFD)", x); \
1422: } while (0)
1423:
1.2 markus 1424: static void
1.114 djm 1425: monitor_openfds(struct monitor *mon, int do_logfds)
1.3 markus 1426: {
1.114 djm 1427: int pair[2];
1.171 markus 1428: #ifdef SO_ZEROIZE
1429: int on = 1;
1430: #endif
1.114 djm 1431:
1.1 provos 1432: if (socketpair(AF_UNIX, SOCK_STREAM, 0, pair) == -1)
1.114 djm 1433: fatal("%s: socketpair: %s", __func__, strerror(errno));
1.171 markus 1434: #ifdef SO_ZEROIZE
1435: if (setsockopt(pair[0], SOL_SOCKET, SO_ZEROIZE, &on, sizeof(on)) < 0)
1436: error("setsockopt SO_ZEROIZE(0): %.100s", strerror(errno));
1437: if (setsockopt(pair[1], SOL_SOCKET, SO_ZEROIZE, &on, sizeof(on)) < 0)
1438: error("setsockopt SO_ZEROIZE(1): %.100s", strerror(errno));
1439: #endif
1.1 provos 1440: FD_CLOSEONEXEC(pair[0]);
1441: FD_CLOSEONEXEC(pair[1]);
1.114 djm 1442: mon->m_recvfd = pair[0];
1443: mon->m_sendfd = pair[1];
1444:
1445: if (do_logfds) {
1446: if (pipe(pair) == -1)
1447: fatal("%s: pipe: %s", __func__, strerror(errno));
1448: FD_CLOSEONEXEC(pair[0]);
1449: FD_CLOSEONEXEC(pair[1]);
1450: mon->m_log_recvfd = pair[0];
1451: mon->m_log_sendfd = pair[1];
1452: } else
1453: mon->m_log_recvfd = mon->m_log_sendfd = -1;
1.1 provos 1454: }
1455:
1456: #define MM_MEMSIZE 65536
1457:
1458: struct monitor *
1459: monitor_init(void)
1460: {
1461: struct monitor *mon;
1462:
1.75 djm 1463: mon = xcalloc(1, sizeof(*mon));
1.114 djm 1464: monitor_openfds(mon, 1);
1.1 provos 1465:
1466: return mon;
1467: }
1468:
1469: void
1470: monitor_reinit(struct monitor *mon)
1471: {
1.114 djm 1472: monitor_openfds(mon, 0);
1.1 provos 1473: }
1.46 markus 1474:
1475: #ifdef GSSAPI
1476: int
1.191 djm 1477: mm_answer_gss_setup_ctx(struct ssh *ssh, int sock, struct sshbuf *m)
1.46 markus 1478: {
1.59 avsm 1479: gss_OID_desc goid;
1.46 markus 1480: OM_uint32 major;
1.183 markus 1481: size_t len;
1.184 djm 1482: u_char *p;
1.183 markus 1483: int r;
1.46 markus 1484:
1.164 djm 1485: if (!options.gss_authentication)
1486: fatal("%s: GSSAPI authentication not enabled", __func__);
1487:
1.184 djm 1488: if ((r = sshbuf_get_string(m, &p, &len)) != 0)
1.183 markus 1489: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.184 djm 1490: goid.elements = p;
1.59 avsm 1491: goid.length = len;
1.46 markus 1492:
1.59 avsm 1493: major = ssh_gssapi_server_ctx(&gsscontext, &goid);
1.46 markus 1494:
1.124 djm 1495: free(goid.elements);
1.46 markus 1496:
1.183 markus 1497: sshbuf_reset(m);
1498: if ((r = sshbuf_put_u32(m, major)) != 0)
1499: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.46 markus 1500:
1.64 stevesk 1501: mm_request_send(sock, MONITOR_ANS_GSSSETUP, m);
1.46 markus 1502:
1503: /* Now we have a context, enable the step */
1504: monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 1);
1505:
1506: return (0);
1507: }
1508:
1509: int
1.191 djm 1510: mm_answer_gss_accept_ctx(struct ssh *ssh, int sock, struct sshbuf *m)
1.46 markus 1511: {
1512: gss_buffer_desc in;
1513: gss_buffer_desc out = GSS_C_EMPTY_BUFFER;
1.64 stevesk 1514: OM_uint32 major, minor;
1.46 markus 1515: OM_uint32 flags = 0; /* GSI needs this */
1.183 markus 1516: int r;
1.46 markus 1517:
1.164 djm 1518: if (!options.gss_authentication)
1519: fatal("%s: GSSAPI authentication not enabled", __func__);
1520:
1.184 djm 1521: if ((r = ssh_gssapi_get_buffer_desc(m, &in)) != 0)
1.183 markus 1522: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.46 markus 1523: major = ssh_gssapi_accept_ctx(gsscontext, &in, &out, &flags);
1.124 djm 1524: free(in.value);
1.46 markus 1525:
1.183 markus 1526: sshbuf_reset(m);
1527: if ((r = sshbuf_put_u32(m, major)) != 0 ||
1528: (r = sshbuf_put_string(m, out.value, out.length)) != 0 ||
1529: (r = sshbuf_put_u32(m, flags)) != 0)
1530: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.59 avsm 1531: mm_request_send(sock, MONITOR_ANS_GSSSTEP, m);
1.46 markus 1532:
1533: gss_release_buffer(&minor, &out);
1534:
1.64 stevesk 1535: if (major == GSS_S_COMPLETE) {
1.46 markus 1536: monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 0);
1537: monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
1.52 markus 1538: monitor_permit(mon_dispatch, MONITOR_REQ_GSSCHECKMIC, 1);
1.46 markus 1539: }
1540: return (0);
1541: }
1542:
1543: int
1.191 djm 1544: mm_answer_gss_checkmic(struct ssh *ssh, int sock, struct sshbuf *m)
1.52 markus 1545: {
1546: gss_buffer_desc gssbuf, mic;
1547: OM_uint32 ret;
1.184 djm 1548: int r;
1.54 djm 1549:
1.164 djm 1550: if (!options.gss_authentication)
1551: fatal("%s: GSSAPI authentication not enabled", __func__);
1552:
1.184 djm 1553: if ((r = ssh_gssapi_get_buffer_desc(m, &gssbuf)) != 0 ||
1554: (r = ssh_gssapi_get_buffer_desc(m, &mic)) != 0)
1.183 markus 1555: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.54 djm 1556:
1.52 markus 1557: ret = ssh_gssapi_checkmic(gsscontext, &gssbuf, &mic);
1.54 djm 1558:
1.124 djm 1559: free(gssbuf.value);
1560: free(mic.value);
1.54 djm 1561:
1.183 markus 1562: sshbuf_reset(m);
1563: if ((r = sshbuf_put_u32(m, ret)) != 0)
1564: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.54 djm 1565:
1.59 avsm 1566: mm_request_send(sock, MONITOR_ANS_GSSCHECKMIC, m);
1.54 djm 1567:
1.52 markus 1568: if (!GSS_ERROR(ret))
1569: monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
1.54 djm 1570:
1.52 markus 1571: return (0);
1572: }
1573:
1574: int
1.191 djm 1575: mm_answer_gss_userok(struct ssh *ssh, int sock, struct sshbuf *m)
1.46 markus 1576: {
1.184 djm 1577: int r, authenticated;
1.172 djm 1578: const char *displayname;
1.164 djm 1579:
1580: if (!options.gss_authentication)
1581: fatal("%s: GSSAPI authentication not enabled", __func__);
1.46 markus 1582:
1583: authenticated = authctxt->valid && ssh_gssapi_userok(authctxt->user);
1584:
1.183 markus 1585: sshbuf_reset(m);
1586: if ((r = sshbuf_put_u32(m, authenticated)) != 0)
1587: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.46 markus 1588:
1589: debug3("%s: sending result %d", __func__, authenticated);
1.59 avsm 1590: mm_request_send(sock, MONITOR_ANS_GSSUSEROK, m);
1.46 markus 1591:
1.64 stevesk 1592: auth_method = "gssapi-with-mic";
1.172 djm 1593:
1594: if ((displayname = ssh_gssapi_displayname()) != NULL)
1595: auth2_record_info(authctxt, "%s", displayname);
1.46 markus 1596:
1597: /* Monitor loop will terminate if authenticated */
1598: return (authenticated);
1599: }
1600: #endif /* GSSAPI */
1.100 djm 1601:
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