Annotation of src/usr.bin/ssh/monitor.c, Revision 1.215
1.215 ! djm 1: /* $OpenBSD: monitor.c,v 1.214 2020/08/27 01:07:09 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"
1.203 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;
92: extern u_char session_id[];
1.181 markus 93: extern struct sshbuf *loginmsg;
1.180 djm 94: extern struct sshauthopt *auth_opts; /* XXX move to permanent ssh->authctxt? */
1.1 provos 95:
96: /* State exported from the child */
1.139 markus 97: static struct sshbuf *child_state;
1.1 provos 98:
1.43 markus 99: /* Functions on the monitor that answer unprivileged requests */
1.1 provos 100:
1.191 djm 101: int mm_answer_moduli(struct ssh *, int, struct sshbuf *);
102: int mm_answer_sign(struct ssh *, int, struct sshbuf *);
103: int mm_answer_pwnamallow(struct ssh *, int, struct sshbuf *);
104: int mm_answer_auth2_read_banner(struct ssh *, int, struct sshbuf *);
105: int mm_answer_authserv(struct ssh *, int, struct sshbuf *);
106: int mm_answer_authpassword(struct ssh *, int, struct sshbuf *);
107: int mm_answer_bsdauthquery(struct ssh *, int, struct sshbuf *);
108: int mm_answer_bsdauthrespond(struct ssh *, int, struct sshbuf *);
109: int mm_answer_skeyquery(struct ssh *, int, struct sshbuf *);
110: int mm_answer_skeyrespond(struct ssh *, int, struct sshbuf *);
111: int mm_answer_keyallowed(struct ssh *, int, struct sshbuf *);
112: int mm_answer_keyverify(struct ssh *, int, struct sshbuf *);
113: int mm_answer_pty(struct ssh *, int, struct sshbuf *);
114: int mm_answer_pty_cleanup(struct ssh *, int, struct sshbuf *);
115: int mm_answer_term(struct ssh *, int, struct sshbuf *);
116: int mm_answer_rsa_keyallowed(struct ssh *, int, struct sshbuf *);
117: int mm_answer_rsa_challenge(struct ssh *, int, struct sshbuf *);
118: int mm_answer_rsa_response(struct ssh *, int, struct sshbuf *);
119: int mm_answer_sesskey(struct ssh *, int, struct sshbuf *);
120: int mm_answer_sessid(struct ssh *, int, struct sshbuf *);
1.1 provos 121:
1.46 markus 122: #ifdef GSSAPI
1.191 djm 123: int mm_answer_gss_setup_ctx(struct ssh *, int, struct sshbuf *);
124: int mm_answer_gss_accept_ctx(struct ssh *, int, struct sshbuf *);
125: int mm_answer_gss_userok(struct ssh *, int, struct sshbuf *);
126: int mm_answer_gss_checkmic(struct ssh *, int, struct sshbuf *);
1.46 markus 127: #endif
1.25 itojun 128:
1.1 provos 129: static Authctxt *authctxt;
1.132 markus 130:
1.1 provos 131: /* local state for key verify */
132: static u_char *key_blob = NULL;
1.183 markus 133: static size_t key_bloblen = 0;
1.1 provos 134: static int key_blobtype = MM_NOKEY;
1.180 djm 135: static struct sshauthopt *key_opts = NULL;
1.26 markus 136: static char *hostbased_cuser = NULL;
137: static char *hostbased_chost = NULL;
1.1 provos 138: static char *auth_method = "unknown";
1.119 djm 139: static char *auth_submethod = NULL;
1.44 markus 140: static u_int session_id2_len = 0;
1.13 markus 141: static u_char *session_id2 = NULL;
1.40 markus 142: static pid_t monitor_child_pid;
1.1 provos 143:
144: struct mon_table {
145: enum monitor_reqtype type;
146: int flags;
1.191 djm 147: int (*f)(struct ssh *, int, struct sshbuf *);
1.1 provos 148: };
149:
150: #define MON_ISAUTH 0x0004 /* Required for Authentication */
151: #define MON_AUTHDECIDE 0x0008 /* Decides Authentication */
152: #define MON_ONCE 0x0010 /* Disable after calling */
1.77 dtucker 153: #define MON_ALOG 0x0020 /* Log auth attempt without authenticating */
1.1 provos 154:
155: #define MON_AUTH (MON_ISAUTH|MON_AUTHDECIDE)
156:
157: #define MON_PERMIT 0x1000 /* Request is permitted */
158:
1.191 djm 159: static int monitor_read(struct ssh *, struct monitor *, struct mon_table *,
160: struct mon_table **);
161: static int monitor_read_log(struct monitor *);
162:
1.1 provos 163: struct mon_table mon_dispatch_proto20[] = {
1.132 markus 164: #ifdef WITH_OPENSSL
1.1 provos 165: {MONITOR_REQ_MODULI, MON_ONCE, mm_answer_moduli},
1.132 markus 166: #endif
1.1 provos 167: {MONITOR_REQ_SIGN, MON_ONCE, mm_answer_sign},
168: {MONITOR_REQ_PWNAM, MON_ONCE, mm_answer_pwnamallow},
169: {MONITOR_REQ_AUTHSERV, MON_ONCE, mm_answer_authserv},
1.10 djm 170: {MONITOR_REQ_AUTH2_READ_BANNER, MON_ONCE, mm_answer_auth2_read_banner},
1.1 provos 171: {MONITOR_REQ_AUTHPASSWORD, MON_AUTH, mm_answer_authpassword},
172: {MONITOR_REQ_BSDAUTHQUERY, MON_ISAUTH, mm_answer_bsdauthquery},
1.66 stevesk 173: {MONITOR_REQ_BSDAUTHRESPOND, MON_AUTH, mm_answer_bsdauthrespond},
1.1 provos 174: {MONITOR_REQ_KEYALLOWED, MON_ISAUTH, mm_answer_keyallowed},
175: {MONITOR_REQ_KEYVERIFY, MON_AUTH, mm_answer_keyverify},
1.46 markus 176: #ifdef GSSAPI
177: {MONITOR_REQ_GSSSETUP, MON_ISAUTH, mm_answer_gss_setup_ctx},
1.165 djm 178: {MONITOR_REQ_GSSSTEP, 0, mm_answer_gss_accept_ctx},
179: {MONITOR_REQ_GSSUSEROK, MON_ONCE|MON_AUTHDECIDE, mm_answer_gss_userok},
180: {MONITOR_REQ_GSSCHECKMIC, MON_ONCE, mm_answer_gss_checkmic},
1.46 markus 181: #endif
1.1 provos 182: {0, 0, NULL}
183: };
184:
185: struct mon_table mon_dispatch_postauth20[] = {
1.132 markus 186: #ifdef WITH_OPENSSL
1.1 provos 187: {MONITOR_REQ_MODULI, 0, mm_answer_moduli},
1.132 markus 188: #endif
1.1 provos 189: {MONITOR_REQ_SIGN, 0, mm_answer_sign},
190: {MONITOR_REQ_PTY, 0, mm_answer_pty},
191: {MONITOR_REQ_PTYCLEANUP, 0, mm_answer_pty_cleanup},
192: {MONITOR_REQ_TERM, 0, mm_answer_term},
193: {0, 0, NULL}
194: };
195:
196: struct mon_table *mon_dispatch;
197:
198: /* Specifies if a certain message is allowed at the moment */
199: static void
200: monitor_permit(struct mon_table *ent, enum monitor_reqtype type, int permit)
201: {
202: while (ent->f != NULL) {
203: if (ent->type == type) {
204: ent->flags &= ~MON_PERMIT;
205: ent->flags |= permit ? MON_PERMIT : 0;
206: return;
207: }
208: ent++;
209: }
210: }
211:
212: static void
213: monitor_permit_authentications(int permit)
214: {
215: struct mon_table *ent = mon_dispatch;
216:
217: while (ent->f != NULL) {
218: if (ent->flags & MON_AUTH) {
219: ent->flags &= ~MON_PERMIT;
220: ent->flags |= permit ? MON_PERMIT : 0;
221: }
222: ent++;
223: }
224: }
225:
1.50 markus 226: void
1.191 djm 227: monitor_child_preauth(struct ssh *ssh, struct monitor *pmonitor)
1.1 provos 228: {
229: struct mon_table *ent;
1.119 djm 230: int authenticated = 0, partial = 0;
1.1 provos 231:
232: debug3("preauth child monitor started");
233:
1.179 tb 234: if (pmonitor->m_recvfd >= 0)
235: close(pmonitor->m_recvfd);
236: if (pmonitor->m_log_sendfd >= 0)
237: close(pmonitor->m_log_sendfd);
1.114 djm 238: pmonitor->m_log_sendfd = pmonitor->m_recvfd = -1;
239:
1.191 djm 240: authctxt = (Authctxt *)ssh->authctxt;
1.50 markus 241: memset(authctxt, 0, sizeof(*authctxt));
1.180 djm 242: ssh->authctxt = authctxt;
1.50 markus 243:
1.162 markus 244: mon_dispatch = mon_dispatch_proto20;
245: /* Permit requests for moduli and signatures */
246: monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
247: monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
1.1 provos 248:
249: /* The first few requests do not require asynchronous access */
250: while (!authenticated) {
1.119 djm 251: partial = 0;
1.77 dtucker 252: auth_method = "unknown";
1.119 djm 253: auth_submethod = NULL;
1.172 djm 254: auth2_authctxt_reset_info(authctxt);
255:
1.191 djm 256: authenticated = (monitor_read(ssh, pmonitor,
257: mon_dispatch, &ent) == 1);
1.118 djm 258:
259: /* Special handling for multiple required authentications */
260: if (options.num_auth_methods != 0) {
261: if (authenticated &&
262: !auth2_update_methods_lists(authctxt,
1.122 markus 263: auth_method, auth_submethod)) {
1.118 djm 264: debug3("%s: method %s: partial", __func__,
265: auth_method);
266: authenticated = 0;
1.119 djm 267: partial = 1;
1.118 djm 268: }
269: }
270:
1.1 provos 271: if (authenticated) {
272: if (!(ent->flags & MON_AUTHDECIDE))
273: fatal("%s: unexpected authentication from %d",
1.14 markus 274: __func__, ent->type);
1.1 provos 275: if (authctxt->pw->pw_uid == 0 &&
1.180 djm 276: !auth_root_allowed(ssh, auth_method))
1.1 provos 277: authenticated = 0;
278: }
1.77 dtucker 279: if (ent->flags & (MON_AUTHDECIDE|MON_ALOG)) {
1.190 djm 280: auth_log(ssh, authenticated, partial,
1.125 djm 281: auth_method, auth_submethod);
1.150 djm 282: if (!partial && !authenticated)
1.1 provos 283: authctxt->failures++;
1.172 djm 284: if (authenticated || partial) {
285: auth2_update_session_info(authctxt,
286: auth_method, auth_submethod);
287: }
1.1 provos 288: }
289: }
290:
291: if (!authctxt->valid)
1.14 markus 292: fatal("%s: authenticated invalid user", __func__);
1.77 dtucker 293: if (strcmp(auth_method, "unknown") == 0)
294: fatal("%s: authentication method name unknown", __func__);
1.1 provos 295:
296: debug("%s: %s has been authenticated by privileged process",
1.14 markus 297: __func__, authctxt->user);
1.180 djm 298: ssh->authctxt = NULL;
1.167 djm 299: ssh_packet_set_log_preamble(ssh, "user %s", authctxt->user);
1.1 provos 300:
1.192 djm 301: mm_get_keystate(ssh, pmonitor);
1.120 markus 302:
303: /* Drain any buffered messages from the child */
304: while (pmonitor->m_log_recvfd != -1 && monitor_read_log(pmonitor) == 0)
305: ;
1.114 djm 306:
1.179 tb 307: if (pmonitor->m_recvfd >= 0)
308: close(pmonitor->m_recvfd);
309: if (pmonitor->m_log_sendfd >= 0)
310: close(pmonitor->m_log_sendfd);
1.114 djm 311: pmonitor->m_sendfd = pmonitor->m_log_recvfd = -1;
1.1 provos 312: }
313:
1.40 markus 314: static void
315: monitor_set_child_handler(pid_t pid)
316: {
317: monitor_child_pid = pid;
318: }
319:
320: static void
1.59 avsm 321: monitor_child_handler(int sig)
1.40 markus 322: {
1.59 avsm 323: kill(monitor_child_pid, sig);
1.40 markus 324: }
325:
1.1 provos 326: void
1.191 djm 327: monitor_child_postauth(struct ssh *ssh, struct monitor *pmonitor)
1.1 provos 328: {
1.114 djm 329: close(pmonitor->m_recvfd);
330: pmonitor->m_recvfd = -1;
331:
1.40 markus 332: monitor_set_child_handler(pmonitor->m_pid);
1.207 dtucker 333: ssh_signal(SIGHUP, &monitor_child_handler);
334: ssh_signal(SIGTERM, &monitor_child_handler);
335: ssh_signal(SIGINT, &monitor_child_handler);
1.40 markus 336:
1.162 markus 337: mon_dispatch = mon_dispatch_postauth20;
338:
339: /* Permit requests for moduli and signatures */
340: monitor_permit(mon_dispatch, MONITOR_REQ_MODULI, 1);
341: monitor_permit(mon_dispatch, MONITOR_REQ_SIGN, 1);
342: monitor_permit(mon_dispatch, MONITOR_REQ_TERM, 1);
1.1 provos 343:
1.180 djm 344: if (auth_opts->permit_pty_flag) {
1.1 provos 345: monitor_permit(mon_dispatch, MONITOR_REQ_PTY, 1);
346: monitor_permit(mon_dispatch, MONITOR_REQ_PTYCLEANUP, 1);
347: }
348:
349: for (;;)
1.191 djm 350: monitor_read(ssh, pmonitor, mon_dispatch, NULL);
1.1 provos 351: }
352:
1.114 djm 353: static int
354: monitor_read_log(struct monitor *pmonitor)
355: {
1.183 markus 356: struct sshbuf *logmsg;
1.215 ! djm 357: u_int len, level, line;
! 358: char *msg, *file, *func;
1.183 markus 359: u_char *p;
360: int r;
1.114 djm 361:
1.183 markus 362: if ((logmsg = sshbuf_new()) == NULL)
363: fatal("%s: sshbuf_new", __func__);
1.114 djm 364:
365: /* Read length */
1.183 markus 366: if ((r = sshbuf_reserve(logmsg, 4, &p)) != 0)
367: fatal("%s: reserve: %s", __func__, ssh_err(r));
368: if (atomicio(read, pmonitor->m_log_recvfd, p, 4) != 4) {
1.114 djm 369: if (errno == EPIPE) {
1.183 markus 370: sshbuf_free(logmsg);
1.114 djm 371: debug("%s: child log fd closed", __func__);
372: close(pmonitor->m_log_recvfd);
373: pmonitor->m_log_recvfd = -1;
374: return -1;
375: }
376: fatal("%s: log fd read: %s", __func__, strerror(errno));
377: }
1.183 markus 378: if ((r = sshbuf_get_u32(logmsg, &len)) != 0)
379: fatal("%s: get len: %s", __func__, ssh_err(r));
1.114 djm 380: if (len <= 4 || len > 8192)
381: fatal("%s: invalid log message length %u", __func__, len);
382:
383: /* Read severity, message */
1.183 markus 384: sshbuf_reset(logmsg);
385: if ((r = sshbuf_reserve(logmsg, len, &p)) != 0)
386: fatal("%s: reserve: %s", __func__, ssh_err(r));
387: if (atomicio(read, pmonitor->m_log_recvfd, p, len) != len)
1.114 djm 388: fatal("%s: log fd read: %s", __func__, strerror(errno));
1.215 ! djm 389: if ((r = sshbuf_get_cstring(logmsg, &file, NULL)) != 0 ||
! 390: (r = sshbuf_get_cstring(logmsg, &func, NULL)) != 0 ||
! 391: (r = sshbuf_get_u32(logmsg, &line)) != 0 ||
! 392: (r = sshbuf_get_u32(logmsg, &level)) != 0 ||
1.183 markus 393: (r = sshbuf_get_cstring(logmsg, &msg, NULL)) != 0)
394: fatal("%s: decode: %s", __func__, ssh_err(r));
1.114 djm 395:
396: /* Log it */
397: if (log_level_name(level) == NULL)
398: fatal("%s: invalid log level %u (corrupted message?)",
399: __func__, level);
1.215 ! djm 400: sshlog(file, func, line, 0, level, "%s [preauth]", msg);
1.114 djm 401:
1.183 markus 402: sshbuf_free(logmsg);
1.215 ! djm 403: free(file);
! 404: free(func);
1.124 djm 405: free(msg);
1.114 djm 406:
407: return 0;
408: }
409:
1.191 djm 410: static int
411: monitor_read(struct ssh *ssh, struct monitor *pmonitor, struct mon_table *ent,
1.1 provos 412: struct mon_table **pent)
413: {
1.183 markus 414: struct sshbuf *m;
415: int r, ret;
1.1 provos 416: u_char type;
1.114 djm 417: struct pollfd pfd[2];
418:
419: for (;;) {
1.130 tedu 420: memset(&pfd, 0, sizeof(pfd));
1.114 djm 421: pfd[0].fd = pmonitor->m_sendfd;
422: pfd[0].events = POLLIN;
423: pfd[1].fd = pmonitor->m_log_recvfd;
424: pfd[1].events = pfd[1].fd == -1 ? 0 : POLLIN;
1.115 djm 425: if (poll(pfd, pfd[1].fd == -1 ? 1 : 2, -1) == -1) {
426: if (errno == EINTR || errno == EAGAIN)
427: continue;
1.114 djm 428: fatal("%s: poll: %s", __func__, strerror(errno));
1.115 djm 429: }
1.114 djm 430: if (pfd[1].revents) {
431: /*
432: * Drain all log messages before processing next
433: * monitor request.
434: */
435: monitor_read_log(pmonitor);
436: continue;
437: }
438: if (pfd[0].revents)
439: break; /* Continues below */
440: }
1.1 provos 441:
1.183 markus 442: if ((m = sshbuf_new()) == NULL)
443: fatal("%s: sshbuf_new", __func__);
1.1 provos 444:
1.183 markus 445: mm_request_receive(pmonitor->m_sendfd, m);
446: if ((r = sshbuf_get_u8(m, &type)) != 0)
447: fatal("%s: decode: %s", __func__, ssh_err(r));
1.1 provos 448:
1.14 markus 449: debug3("%s: checking request %d", __func__, type);
1.1 provos 450:
451: while (ent->f != NULL) {
452: if (ent->type == type)
453: break;
454: ent++;
455: }
456:
457: if (ent->f != NULL) {
458: if (!(ent->flags & MON_PERMIT))
1.14 markus 459: fatal("%s: unpermitted request %d", __func__,
1.1 provos 460: type);
1.191 djm 461: ret = (*ent->f)(ssh, pmonitor->m_sendfd, m);
1.183 markus 462: sshbuf_free(m);
1.1 provos 463:
464: /* The child may use this request only once, disable it */
465: if (ent->flags & MON_ONCE) {
1.14 markus 466: debug2("%s: %d used once, disabling now", __func__,
1.1 provos 467: type);
468: ent->flags &= ~MON_PERMIT;
469: }
470:
471: if (pent != NULL)
472: *pent = ent;
1.3 markus 473:
1.1 provos 474: return ret;
475: }
476:
1.14 markus 477: fatal("%s: unsupported request: %d", __func__, type);
1.1 provos 478:
479: /* NOTREACHED */
480: return (-1);
481: }
482:
483: /* allowed key state */
484: static int
1.203 djm 485: monitor_allowed_key(const u_char *blob, u_int bloblen)
1.1 provos 486: {
487: /* make sure key is allowed */
488: if (key_blob == NULL || key_bloblen != bloblen ||
1.108 djm 489: timingsafe_bcmp(key_blob, blob, key_bloblen))
1.1 provos 490: return (0);
491: return (1);
492: }
493:
494: static void
495: monitor_reset_key_state(void)
496: {
497: /* reset state */
1.124 djm 498: free(key_blob);
499: free(hostbased_cuser);
500: free(hostbased_chost);
1.180 djm 501: sshauthopt_free(key_opts);
1.1 provos 502: key_blob = NULL;
503: key_bloblen = 0;
504: key_blobtype = MM_NOKEY;
1.180 djm 505: key_opts = NULL;
1.1 provos 506: hostbased_cuser = NULL;
507: hostbased_chost = NULL;
508: }
509:
1.132 markus 510: #ifdef WITH_OPENSSL
1.1 provos 511: int
1.191 djm 512: mm_answer_moduli(struct ssh *ssh, int sock, struct sshbuf *m)
1.1 provos 513: {
514: DH *dh;
1.187 djm 515: const BIGNUM *dh_p, *dh_g;
1.183 markus 516: int r;
517: u_int min, want, max;
1.1 provos 518:
1.183 markus 519: if ((r = sshbuf_get_u32(m, &min)) != 0 ||
520: (r = sshbuf_get_u32(m, &want)) != 0 ||
521: (r = sshbuf_get_u32(m, &max)) != 0)
522: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.1 provos 523:
524: debug3("%s: got parameters: %d %d %d",
1.14 markus 525: __func__, min, want, max);
1.1 provos 526: /* We need to check here, too, in case the child got corrupted */
527: if (max < min || want < min || max < want)
528: fatal("%s: bad parameters: %d %d %d",
1.14 markus 529: __func__, min, want, max);
1.1 provos 530:
1.183 markus 531: sshbuf_reset(m);
1.1 provos 532:
533: dh = choose_dh(min, want, max);
534: if (dh == NULL) {
1.183 markus 535: if ((r = sshbuf_put_u8(m, 0)) != 0)
536: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.1 provos 537: return (0);
538: } else {
539: /* Send first bignum */
1.187 djm 540: DH_get0_pqg(dh, &dh_p, NULL, &dh_g);
1.183 markus 541: if ((r = sshbuf_put_u8(m, 1)) != 0 ||
1.187 djm 542: (r = sshbuf_put_bignum2(m, dh_p)) != 0 ||
543: (r = sshbuf_put_bignum2(m, dh_g)) != 0)
1.183 markus 544: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.3 markus 545:
1.1 provos 546: DH_free(dh);
547: }
1.59 avsm 548: mm_request_send(sock, MONITOR_ANS_MODULI, m);
1.1 provos 549: return (0);
550: }
1.132 markus 551: #endif
1.1 provos 552:
553: int
1.191 djm 554: mm_answer_sign(struct ssh *ssh, int sock, struct sshbuf *m)
1.1 provos 555: {
1.138 djm 556: extern int auth_sock; /* XXX move to state struct? */
557: struct sshkey *key;
1.157 djm 558: struct sshbuf *sigbuf = NULL;
559: u_char *p = NULL, *signature = NULL;
560: char *alg = NULL;
1.155 markus 561: size_t datlen, siglen, alglen;
1.159 djm 562: int r, is_proof = 0;
1.185 markus 563: u_int keyid, compat;
1.145 djm 564: const char proof_req[] = "hostkeys-prove-00@openssh.com";
1.3 markus 565:
1.14 markus 566: debug3("%s", __func__);
1.1 provos 567:
1.138 djm 568: if ((r = sshbuf_get_u32(m, &keyid)) != 0 ||
1.155 markus 569: (r = sshbuf_get_string(m, &p, &datlen)) != 0 ||
1.185 markus 570: (r = sshbuf_get_cstring(m, &alg, &alglen)) != 0 ||
571: (r = sshbuf_get_u32(m, &compat)) != 0)
1.138 djm 572: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.159 djm 573: if (keyid > INT_MAX)
574: fatal("%s: invalid key ID", __func__);
1.1 provos 575:
1.69 djm 576: /*
1.110 djm 577: * Supported KEX types use SHA1 (20 bytes), SHA256 (32 bytes),
578: * SHA384 (48 bytes) and SHA512 (64 bytes).
1.144 djm 579: *
580: * Otherwise, verify the signature request is for a hostkey
581: * proof.
582: *
583: * XXX perform similar check for KEX signature requests too?
584: * it's not trivial, since what is signed is the hash, rather
585: * than the full kex structure...
1.69 djm 586: */
1.144 djm 587: if (datlen != 20 && datlen != 32 && datlen != 48 && datlen != 64) {
588: /*
589: * Construct expected hostkey proof and compare it to what
590: * the client sent us.
591: */
592: if (session_id2_len == 0) /* hostkeys is never first */
593: fatal("%s: bad data length: %zu", __func__, datlen);
594: if ((key = get_hostkey_public_by_index(keyid, ssh)) == NULL)
595: fatal("%s: no hostkey for index %d", __func__, keyid);
596: if ((sigbuf = sshbuf_new()) == NULL)
597: fatal("%s: sshbuf_new", __func__);
1.145 djm 598: if ((r = sshbuf_put_cstring(sigbuf, proof_req)) != 0 ||
599: (r = sshbuf_put_string(sigbuf, session_id2,
1.152 jsg 600: session_id2_len)) != 0 ||
1.144 djm 601: (r = sshkey_puts(key, sigbuf)) != 0)
602: fatal("%s: couldn't prepare private key "
603: "proof buffer: %s", __func__, ssh_err(r));
604: if (datlen != sshbuf_len(sigbuf) ||
605: memcmp(p, sshbuf_ptr(sigbuf), sshbuf_len(sigbuf)) != 0)
606: fatal("%s: bad data length: %zu, hostkey proof len %zu",
607: __func__, datlen, sshbuf_len(sigbuf));
608: sshbuf_free(sigbuf);
609: is_proof = 1;
610: }
1.1 provos 611:
1.13 markus 612: /* save session id, it will be passed on the first call */
613: if (session_id2_len == 0) {
614: session_id2_len = datlen;
615: session_id2 = xmalloc(session_id2_len);
616: memcpy(session_id2, p, session_id2_len);
617: }
618:
1.127 markus 619: if ((key = get_hostkey_by_index(keyid)) != NULL) {
1.155 markus 620: if ((r = sshkey_sign(key, &signature, &siglen, p, datlen, alg,
1.213 djm 621: options.sk_provider, NULL, compat)) != 0)
1.138 djm 622: fatal("%s: sshkey_sign failed: %s",
623: __func__, ssh_err(r));
1.144 djm 624: } else if ((key = get_hostkey_public_by_index(keyid, ssh)) != NULL &&
1.138 djm 625: auth_sock > 0) {
626: if ((r = ssh_agent_sign(auth_sock, key, &signature, &siglen,
1.185 markus 627: p, datlen, alg, compat)) != 0) {
1.138 djm 628: fatal("%s: ssh_agent_sign failed: %s",
629: __func__, ssh_err(r));
630: }
1.127 markus 631: } else
1.14 markus 632: fatal("%s: no hostkey from index %d", __func__, keyid);
1.1 provos 633:
1.144 djm 634: debug3("%s: %s signature %p(%zu)", __func__,
1.199 djm 635: is_proof ? "hostkey proof" : "KEX", signature, siglen);
1.1 provos 636:
1.138 djm 637: sshbuf_reset(m);
638: if ((r = sshbuf_put_string(m, signature, siglen)) != 0)
639: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.1 provos 640:
1.157 djm 641: free(alg);
1.124 djm 642: free(p);
643: free(signature);
1.1 provos 644:
1.59 avsm 645: mm_request_send(sock, MONITOR_ANS_SIGN, m);
1.1 provos 646:
647: /* Turn on permissions for getpwnam */
648: monitor_permit(mon_dispatch, MONITOR_REQ_PWNAM, 1);
649:
650: return (0);
651: }
652:
653: /* Retrieves the password entry and also checks if the user is permitted */
654:
655: int
1.191 djm 656: mm_answer_pwnamallow(struct ssh *ssh, int sock, struct sshbuf *m)
1.1 provos 657: {
1.60 dtucker 658: char *username;
1.1 provos 659: struct passwd *pwent;
1.183 markus 660: int r, allowed = 0;
1.113 djm 661: u_int i;
1.3 markus 662:
1.14 markus 663: debug3("%s", __func__);
1.1 provos 664:
665: if (authctxt->attempt++ != 0)
1.14 markus 666: fatal("%s: multiple attempts for getpwnam", __func__);
1.1 provos 667:
1.183 markus 668: if ((r = sshbuf_get_cstring(m, &username, NULL)) != 0)
669: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.1 provos 670:
1.190 djm 671: pwent = getpwnamallow(ssh, username);
1.1 provos 672:
1.60 dtucker 673: authctxt->user = xstrdup(username);
674: setproctitle("%s [priv]", pwent ? username : "unknown");
1.124 djm 675: free(username);
1.1 provos 676:
1.183 markus 677: sshbuf_reset(m);
1.1 provos 678:
679: if (pwent == NULL) {
1.183 markus 680: if ((r = sshbuf_put_u8(m, 0)) != 0)
681: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.53 djm 682: authctxt->pw = fakepw();
1.1 provos 683: goto out;
684: }
685:
686: allowed = 1;
1.4 markus 687: authctxt->pw = pwent;
1.1 provos 688: authctxt->valid = 1;
689:
1.183 markus 690: /* XXX don't sent pwent to unpriv; send fake class/dir/shell too */
691: if ((r = sshbuf_put_u8(m, 1)) != 0 ||
692: (r = sshbuf_put_string(m, pwent, sizeof(*pwent))) != 0 ||
693: (r = sshbuf_put_cstring(m, pwent->pw_name)) != 0 ||
694: (r = sshbuf_put_cstring(m, "*")) != 0 ||
695: (r = sshbuf_put_cstring(m, pwent->pw_gecos)) != 0 ||
696: (r = sshbuf_put_cstring(m, pwent->pw_class)) != 0 ||
697: (r = sshbuf_put_cstring(m, pwent->pw_dir)) != 0 ||
698: (r = sshbuf_put_cstring(m, pwent->pw_shell)) != 0)
699: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.94 dtucker 700:
701: out:
1.167 djm 702: ssh_packet_set_log_preamble(ssh, "%suser %s",
703: authctxt->valid ? "authenticating" : "invalid ", authctxt->user);
1.183 markus 704: if ((r = sshbuf_put_string(m, &options, sizeof(options))) != 0)
705: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.112 djm 706:
707: #define M_CP_STROPT(x) do { \
1.183 markus 708: if (options.x != NULL) { \
709: if ((r = sshbuf_put_cstring(m, options.x)) != 0) \
710: fatal("%s: buffer error: %s", \
711: __func__, ssh_err(r)); \
712: } \
1.112 djm 713: } while (0)
1.113 djm 714: #define M_CP_STRARRAYOPT(x, nx) do { \
1.183 markus 715: for (i = 0; i < options.nx; i++) { \
716: if ((r = sshbuf_put_cstring(m, options.x[i])) != 0) \
717: fatal("%s: buffer error: %s", \
718: __func__, ssh_err(r)); \
719: } \
1.113 djm 720: } while (0)
1.112 djm 721: /* See comment in servconf.h */
722: COPY_MATCH_STRING_OPTS();
723: #undef M_CP_STROPT
1.113 djm 724: #undef M_CP_STRARRAYOPT
1.118 djm 725:
726: /* Create valid auth method lists */
1.162 markus 727: if (auth2_setup_methods_lists(authctxt) != 0) {
1.118 djm 728: /*
729: * The monitor will continue long enough to let the child
730: * run to it's packet_disconnect(), but it must not allow any
731: * authentication to succeed.
732: */
733: debug("%s: no valid authentication method lists", __func__);
734: }
735:
1.14 markus 736: debug3("%s: sending MONITOR_ANS_PWNAM: %d", __func__, allowed);
1.59 avsm 737: mm_request_send(sock, MONITOR_ANS_PWNAM, m);
1.1 provos 738:
1.162 markus 739: /* Allow service/style information on the auth context */
740: monitor_permit(mon_dispatch, MONITOR_REQ_AUTHSERV, 1);
741: monitor_permit(mon_dispatch, MONITOR_REQ_AUTH2_READ_BANNER, 1);
1.10 djm 742:
743: return (0);
744: }
745:
1.191 djm 746: int mm_answer_auth2_read_banner(struct ssh *ssh, int sock, struct sshbuf *m)
1.10 djm 747: {
748: char *banner;
1.183 markus 749: int r;
1.10 djm 750:
1.183 markus 751: sshbuf_reset(m);
1.10 djm 752: banner = auth2_read_banner();
1.183 markus 753: if ((r = sshbuf_put_cstring(m, banner != NULL ? banner : "")) != 0)
754: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.59 avsm 755: mm_request_send(sock, MONITOR_ANS_AUTH2_READ_BANNER, m);
1.124 djm 756: free(banner);
1.1 provos 757:
758: return (0);
759: }
760:
761: int
1.191 djm 762: mm_answer_authserv(struct ssh *ssh, int sock, struct sshbuf *m)
1.1 provos 763: {
1.183 markus 764: int r;
765:
1.1 provos 766: monitor_permit_authentications(1);
767:
1.183 markus 768: if ((r = sshbuf_get_cstring(m, &authctxt->service, NULL)) != 0 ||
769: (r = sshbuf_get_cstring(m, &authctxt->style, NULL)) != 0)
770: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.6 stevesk 771: debug3("%s: service=%s, style=%s",
1.14 markus 772: __func__, authctxt->service, authctxt->style);
1.6 stevesk 773:
1.1 provos 774: if (strlen(authctxt->style) == 0) {
1.124 djm 775: free(authctxt->style);
1.1 provos 776: authctxt->style = NULL;
777: }
778:
779: return (0);
780: }
781:
782: int
1.191 djm 783: mm_answer_authpassword(struct ssh *ssh, int sock, struct sshbuf *m)
1.1 provos 784: {
785: static int call_count;
786: char *passwd;
1.183 markus 787: int r, authenticated;
788: size_t plen;
1.1 provos 789:
1.164 djm 790: if (!options.password_authentication)
791: fatal("%s: password authentication not enabled", __func__);
1.183 markus 792: if ((r = sshbuf_get_cstring(m, &passwd, &plen)) != 0)
793: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.1 provos 794: /* Only authenticate if the context is valid */
1.12 markus 795: authenticated = options.password_authentication &&
1.180 djm 796: auth_password(ssh, passwd);
1.209 jsg 797: freezero(passwd, plen);
1.1 provos 798:
1.183 markus 799: sshbuf_reset(m);
800: if ((r = sshbuf_put_u32(m, authenticated)) != 0)
801: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.1 provos 802:
1.14 markus 803: debug3("%s: sending result %d", __func__, authenticated);
1.59 avsm 804: mm_request_send(sock, MONITOR_ANS_AUTHPASSWORD, m);
1.1 provos 805:
806: call_count++;
807: if (plen == 0 && call_count == 1)
808: auth_method = "none";
809: else
810: auth_method = "password";
811:
812: /* Causes monitor loop to terminate if authenticated */
813: return (authenticated);
814: }
815:
816: int
1.191 djm 817: mm_answer_bsdauthquery(struct ssh *ssh, int sock, struct sshbuf *m)
1.1 provos 818: {
819: char *name, *infotxt;
1.183 markus 820: u_int numprompts, *echo_on, success;
1.1 provos 821: char **prompts;
1.183 markus 822: int r;
1.1 provos 823:
1.164 djm 824: if (!options.kbd_interactive_authentication)
825: fatal("%s: kbd-int authentication not enabled", __func__);
1.31 markus 826: success = bsdauth_query(authctxt, &name, &infotxt, &numprompts,
827: &prompts, &echo_on) < 0 ? 0 : 1;
1.1 provos 828:
1.183 markus 829: sshbuf_reset(m);
830: if ((r = sshbuf_put_u32(m, success)) != 0)
831: fatal("%s: buffer error: %s", __func__, ssh_err(r));
832: if (success) {
833: if ((r = sshbuf_put_cstring(m, prompts[0])) != 0)
834: fatal("%s: buffer error: %s", __func__, ssh_err(r));
835: }
1.1 provos 836:
1.31 markus 837: debug3("%s: sending challenge success: %u", __func__, success);
1.59 avsm 838: mm_request_send(sock, MONITOR_ANS_BSDAUTHQUERY, m);
1.1 provos 839:
1.31 markus 840: if (success) {
1.124 djm 841: free(name);
842: free(infotxt);
843: free(prompts);
844: free(echo_on);
1.1 provos 845: }
846:
847: return (0);
848: }
849:
850: int
1.191 djm 851: mm_answer_bsdauthrespond(struct ssh *ssh, int sock, struct sshbuf *m)
1.1 provos 852: {
853: char *response;
1.183 markus 854: int r, authok;
1.1 provos 855:
1.164 djm 856: if (!options.kbd_interactive_authentication)
857: fatal("%s: kbd-int authentication not enabled", __func__);
1.154 mmcc 858: if (authctxt->as == NULL)
1.14 markus 859: fatal("%s: no bsd auth session", __func__);
1.1 provos 860:
1.183 markus 861: if ((r = sshbuf_get_cstring(m, &response, NULL)) != 0)
862: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.12 markus 863: authok = options.challenge_response_authentication &&
864: auth_userresponse(authctxt->as, response, 0);
1.1 provos 865: authctxt->as = NULL;
1.14 markus 866: debug3("%s: <%s> = <%d>", __func__, response, authok);
1.124 djm 867: free(response);
1.1 provos 868:
1.183 markus 869: sshbuf_reset(m);
870: if ((r = sshbuf_put_u32(m, authok)) != 0)
871: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.1 provos 872:
1.14 markus 873: debug3("%s: sending authenticated: %d", __func__, authok);
1.59 avsm 874: mm_request_send(sock, MONITOR_ANS_BSDAUTHRESPOND, m);
1.1 provos 875:
1.162 markus 876: auth_method = "keyboard-interactive";
877: auth_submethod = "bsdauth";
1.1 provos 878:
879: return (authok != 0);
880: }
881:
1.188 djm 882: /*
883: * Check that the key type appears in the supplied pattern list, ignoring
884: * mismatches in the signature algorithm. (Signature algorithm checks are
885: * performed in the unprivileged authentication code).
886: * Returns 1 on success, 0 otherwise.
887: */
888: static int
889: key_base_type_match(const char *method, const struct sshkey *key,
890: const char *list)
891: {
892: char *s, *l, *ol = xstrdup(list);
893: int found = 0;
894:
895: l = ol;
896: for ((s = strsep(&l, ",")); s && *s != '\0'; (s = strsep(&l, ","))) {
897: if (sshkey_type_from_name(s) == key->type) {
898: found = 1;
899: break;
900: }
901: }
902: if (!found) {
903: error("%s key type %s is not in permitted list %s", method,
904: sshkey_ssh_name(key), list);
905: }
906:
907: free(ol);
908: return found;
909: }
910:
1.1 provos 911: int
1.191 djm 912: mm_answer_keyallowed(struct ssh *ssh, int sock, struct sshbuf *m)
1.1 provos 913: {
1.183 markus 914: struct sshkey *key = NULL;
1.26 markus 915: char *cuser, *chost;
1.183 markus 916: u_int pubkey_auth_attempt;
1.1 provos 917: enum mm_keytype type = 0;
1.180 djm 918: int r, allowed = 0;
919: struct sshauthopt *opts = NULL;
1.1 provos 920:
1.14 markus 921: debug3("%s entering", __func__);
1.183 markus 922: if ((r = sshbuf_get_u32(m, &type)) != 0 ||
923: (r = sshbuf_get_cstring(m, &cuser, NULL)) != 0 ||
924: (r = sshbuf_get_cstring(m, &chost, NULL)) != 0 ||
925: (r = sshkey_froms(m, &key)) != 0 ||
926: (r = sshbuf_get_u32(m, &pubkey_auth_attempt)) != 0)
927: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.1 provos 928:
1.14 markus 929: debug3("%s: key_from_blob: %p", __func__, key);
1.1 provos 930:
1.51 djm 931: if (key != NULL && authctxt->valid) {
1.137 djm 932: /* These should not make it past the privsep child */
1.185 markus 933: if (sshkey_type_plain(key->type) == KEY_RSA &&
1.137 djm 934: (datafellows & SSH_BUG_RSASIGMD5) != 0)
935: fatal("%s: passed a SSH_BUG_RSASIGMD5 key", __func__);
936:
1.63 deraadt 937: switch (type) {
1.1 provos 938: case MM_USERKEY:
1.77 dtucker 939: auth_method = "publickey";
1.180 djm 940: if (!options.pubkey_authentication)
941: break;
942: if (auth2_key_already_used(authctxt, key))
943: break;
1.188 djm 944: if (!key_base_type_match(auth_method, key,
945: options.pubkey_key_types))
1.180 djm 946: break;
947: allowed = user_key_allowed(ssh, authctxt->pw, key,
948: pubkey_auth_attempt, &opts);
1.1 provos 949: break;
950: case MM_HOSTKEY:
1.180 djm 951: auth_method = "hostbased";
952: if (!options.hostbased_authentication)
953: break;
954: if (auth2_key_already_used(authctxt, key))
955: break;
1.188 djm 956: if (!key_base_type_match(auth_method, key,
957: options.hostbased_key_types))
1.180 djm 958: break;
1.192 djm 959: allowed = hostbased_key_allowed(ssh, authctxt->pw,
1.1 provos 960: cuser, chost, key);
1.172 djm 961: auth2_record_info(authctxt,
1.126 djm 962: "client user \"%.100s\", client host \"%.100s\"",
963: cuser, chost);
1.1 provos 964: break;
965: default:
1.14 markus 966: fatal("%s: unknown key type %d", __func__, type);
1.1 provos 967: break;
968: }
1.33 markus 969: }
1.161 djm 970:
1.180 djm 971: debug3("%s: %s authentication%s: %s key is %s", __func__,
972: auth_method, pubkey_auth_attempt ? "" : " test",
973: (key == NULL || !authctxt->valid) ? "invalid" : sshkey_type(key),
974: allowed ? "allowed" : "not allowed");
1.161 djm 975:
1.172 djm 976: auth2_record_key(authctxt, 0, key);
1.1 provos 977:
978: /* clear temporarily storage (used by verify) */
979: monitor_reset_key_state();
980:
981: if (allowed) {
982: /* Save temporarily for comparison in verify */
1.183 markus 983: if ((r = sshkey_to_blob(key, &key_blob, &key_bloblen)) != 0)
984: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.1 provos 985: key_blobtype = type;
1.180 djm 986: key_opts = opts;
1.1 provos 987: hostbased_cuser = cuser;
988: hostbased_chost = chost;
1.72 djm 989: } else {
1.77 dtucker 990: /* Log failed attempt */
1.190 djm 991: auth_log(ssh, 0, 0, auth_method, NULL);
1.124 djm 992: free(cuser);
993: free(chost);
1.1 provos 994: }
1.183 markus 995: sshkey_free(key);
1.1 provos 996:
1.183 markus 997: sshbuf_reset(m);
998: if ((r = sshbuf_put_u32(m, allowed)) != 0)
999: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.180 djm 1000: if (opts != NULL && (r = sshauthopt_serialise(opts, m, 1)) != 0)
1001: fatal("%s: sshauthopt_serialise: %s", __func__, ssh_err(r));
1002: mm_request_send(sock, MONITOR_ANS_KEYALLOWED, m);
1.1 provos 1003:
1.180 djm 1004: if (!allowed)
1005: sshauthopt_free(opts);
1.1 provos 1006:
1007: return (0);
1008: }
1009:
1010: static int
1.203 djm 1011: monitor_valid_userblob(const u_char *data, u_int datalen)
1.1 provos 1012: {
1.183 markus 1013: struct sshbuf *b;
1014: const u_char *p;
1.159 djm 1015: char *userstyle, *cp;
1.183 markus 1016: size_t len;
1017: u_char type;
1018: int r, fail = 0;
1.1 provos 1019:
1.203 djm 1020: if ((b = sshbuf_from(data, datalen)) == NULL)
1021: fatal("%s: sshbuf_from", __func__);
1.3 markus 1022:
1.1 provos 1023: if (datafellows & SSH_OLD_SESSIONID) {
1.183 markus 1024: p = sshbuf_ptr(b);
1025: len = sshbuf_len(b);
1.13 markus 1026: if ((session_id2 == NULL) ||
1027: (len < session_id2_len) ||
1.108 djm 1028: (timingsafe_bcmp(p, session_id2, session_id2_len) != 0))
1.13 markus 1029: fail++;
1.183 markus 1030: if ((r = sshbuf_consume(b, session_id2_len)) != 0)
1031: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.1 provos 1032: } else {
1.183 markus 1033: if ((r = sshbuf_get_string_direct(b, &p, &len)) != 0)
1034: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.13 markus 1035: if ((session_id2 == NULL) ||
1036: (len != session_id2_len) ||
1.108 djm 1037: (timingsafe_bcmp(p, session_id2, session_id2_len) != 0))
1.1 provos 1038: fail++;
1039: }
1.183 markus 1040: if ((r = sshbuf_get_u8(b, &type)) != 0)
1041: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1042: if (type != SSH2_MSG_USERAUTH_REQUEST)
1.1 provos 1043: fail++;
1.183 markus 1044: if ((r = sshbuf_get_cstring(b, &cp, NULL)) != 0)
1045: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.121 djm 1046: xasprintf(&userstyle, "%s%s%s", authctxt->user,
1047: authctxt->style ? ":" : "",
1048: authctxt->style ? authctxt->style : "");
1.159 djm 1049: if (strcmp(userstyle, cp) != 0) {
1050: logit("wrong user name passed to monitor: "
1051: "expected %s != %.100s", userstyle, cp);
1.1 provos 1052: fail++;
1053: }
1.124 djm 1054: free(userstyle);
1.159 djm 1055: free(cp);
1.183 markus 1056: if ((r = sshbuf_skip_string(b)) != 0 || /* service */
1057: (r = sshbuf_get_cstring(b, &cp, NULL)) != 0)
1058: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.178 djm 1059: if (strcmp("publickey", cp) != 0)
1060: fail++;
1061: free(cp);
1.183 markus 1062: if ((r = sshbuf_get_u8(b, &type)) != 0)
1063: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1064: if (type == 0)
1.178 djm 1065: fail++;
1.183 markus 1066: if ((r = sshbuf_skip_string(b)) != 0 || /* pkalg */
1067: (r = sshbuf_skip_string(b)) != 0) /* pkblob */
1068: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1069: if (sshbuf_len(b) != 0)
1.1 provos 1070: fail++;
1.183 markus 1071: sshbuf_free(b);
1.1 provos 1072: return (fail == 0);
1073: }
1074:
1075: static int
1.203 djm 1076: monitor_valid_hostbasedblob(const u_char *data, u_int datalen,
1077: const char *cuser, const char *chost)
1.1 provos 1078: {
1.183 markus 1079: struct sshbuf *b;
1080: const u_char *p;
1081: char *cp, *userstyle;
1082: size_t len;
1083: int r, fail = 0;
1084: u_char type;
1.1 provos 1085:
1.203 djm 1086: if ((b = sshbuf_from(data, datalen)) == NULL)
1.183 markus 1087: fatal("%s: sshbuf_new", __func__);
1.203 djm 1088: if ((r = sshbuf_get_string_direct(b, &p, &len)) != 0)
1.183 markus 1089: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.3 markus 1090:
1.13 markus 1091: if ((session_id2 == NULL) ||
1092: (len != session_id2_len) ||
1.108 djm 1093: (timingsafe_bcmp(p, session_id2, session_id2_len) != 0))
1.1 provos 1094: fail++;
1.13 markus 1095:
1.183 markus 1096: if ((r = sshbuf_get_u8(b, &type)) != 0)
1097: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1098: if (type != SSH2_MSG_USERAUTH_REQUEST)
1.1 provos 1099: fail++;
1.183 markus 1100: if ((r = sshbuf_get_cstring(b, &cp, NULL)) != 0)
1101: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.121 djm 1102: xasprintf(&userstyle, "%s%s%s", authctxt->user,
1103: authctxt->style ? ":" : "",
1104: authctxt->style ? authctxt->style : "");
1.183 markus 1105: if (strcmp(userstyle, cp) != 0) {
1106: logit("wrong user name passed to monitor: "
1107: "expected %s != %.100s", userstyle, cp);
1.1 provos 1108: fail++;
1109: }
1.121 djm 1110: free(userstyle);
1.183 markus 1111: free(cp);
1112: if ((r = sshbuf_skip_string(b)) != 0 || /* service */
1113: (r = sshbuf_get_cstring(b, &cp, NULL)) != 0)
1114: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1115: if (strcmp(cp, "hostbased") != 0)
1.1 provos 1116: fail++;
1.183 markus 1117: free(cp);
1118: if ((r = sshbuf_skip_string(b)) != 0 || /* pkalg */
1119: (r = sshbuf_skip_string(b)) != 0) /* pkblob */
1120: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.1 provos 1121:
1122: /* verify client host, strip trailing dot if necessary */
1.183 markus 1123: if ((r = sshbuf_get_cstring(b, &cp, NULL)) != 0)
1124: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1125: if (((len = strlen(cp)) > 0) && cp[len - 1] == '.')
1126: cp[len - 1] = '\0';
1127: if (strcmp(cp, chost) != 0)
1.1 provos 1128: fail++;
1.183 markus 1129: free(cp);
1.1 provos 1130:
1131: /* verify client user */
1.183 markus 1132: if ((r = sshbuf_get_cstring(b, &cp, NULL)) != 0)
1133: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1134: if (strcmp(cp, cuser) != 0)
1.1 provos 1135: fail++;
1.183 markus 1136: free(cp);
1.1 provos 1137:
1.183 markus 1138: if (sshbuf_len(b) != 0)
1.1 provos 1139: fail++;
1.183 markus 1140: sshbuf_free(b);
1.1 provos 1141: return (fail == 0);
1142: }
1143:
1144: int
1.191 djm 1145: mm_answer_keyverify(struct ssh *ssh, int sock, struct sshbuf *m)
1.1 provos 1146: {
1.168 markus 1147: struct sshkey *key;
1.203 djm 1148: const u_char *signature, *data, *blob;
1149: char *sigalg = NULL, *fp = NULL;
1.169 markus 1150: size_t signaturelen, datalen, bloblen;
1.214 djm 1151: int r, ret, req_presence = 0, req_verify = 0, valid_data = 0;
1152: int encoded_ret;
1.202 djm 1153: struct sshkey_sig_details *sig_details = NULL;
1.1 provos 1154:
1.203 djm 1155: if ((r = sshbuf_get_string_direct(m, &blob, &bloblen)) != 0 ||
1156: (r = sshbuf_get_string_direct(m, &signature, &signaturelen)) != 0 ||
1157: (r = sshbuf_get_string_direct(m, &data, &datalen)) != 0 ||
1.176 djm 1158: (r = sshbuf_get_cstring(m, &sigalg, NULL)) != 0)
1.169 markus 1159: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.1 provos 1160:
1161: if (hostbased_cuser == NULL || hostbased_chost == NULL ||
1.8 mouring 1162: !monitor_allowed_key(blob, bloblen))
1.14 markus 1163: fatal("%s: bad key, not previously allowed", __func__);
1.1 provos 1164:
1.177 djm 1165: /* Empty signature algorithm means NULL. */
1166: if (*sigalg == '\0') {
1167: free(sigalg);
1168: sigalg = NULL;
1169: }
1170:
1.169 markus 1171: /* XXX use sshkey_froms here; need to change key_blob, etc. */
1172: if ((r = sshkey_from_blob(blob, bloblen, &key)) != 0)
1173: fatal("%s: bad public key blob: %s", __func__, ssh_err(r));
1.1 provos 1174:
1175: switch (key_blobtype) {
1176: case MM_USERKEY:
1177: valid_data = monitor_valid_userblob(data, datalen);
1.172 djm 1178: auth_method = "publickey";
1.1 provos 1179: break;
1180: case MM_HOSTKEY:
1181: valid_data = monitor_valid_hostbasedblob(data, datalen,
1182: hostbased_cuser, hostbased_chost);
1.172 djm 1183: auth_method = "hostbased";
1.1 provos 1184: break;
1185: default:
1186: valid_data = 0;
1187: break;
1188: }
1189: if (!valid_data)
1.14 markus 1190: fatal("%s: bad signature data blob", __func__);
1.1 provos 1191:
1.203 djm 1192: if ((fp = sshkey_fingerprint(key, options.fingerprint_hash,
1193: SSH_FP_DEFAULT)) == NULL)
1194: fatal("%s: sshkey_fingerprint failed", __func__);
1195:
1.169 markus 1196: ret = sshkey_verify(key, signature, signaturelen, data, datalen,
1.202 djm 1197: sigalg, ssh->compat, &sig_details);
1.201 djm 1198: debug3("%s: %s %p signature %s%s%s", __func__, auth_method, key,
1199: (ret == 0) ? "verified" : "unverified",
1200: (ret != 0) ? ": " : "", (ret != 0) ? ssh_err(ret) : "");
1.203 djm 1201:
1202: if (ret == 0 && key_blobtype == MM_USERKEY && sig_details != NULL) {
1203: req_presence = (options.pubkey_auth_options &
1.204 djm 1204: PUBKEYAUTH_TOUCH_REQUIRED) ||
1205: !key_opts->no_require_user_presence;
1.203 djm 1206: if (req_presence &&
1207: (sig_details->sk_flags & SSH_SK_USER_PRESENCE_REQD) == 0) {
1208: error("public key %s %s signature for %s%s from %.128s "
1.208 naddy 1209: "port %d rejected: user presence "
1210: "(authenticator touch) requirement not met ",
1211: sshkey_type(key), fp,
1.214 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: req_verify = (options.pubkey_auth_options &
1218: PUBKEYAUTH_VERIFY_REQUIRED) || key_opts->require_verify;
1219: if (req_verify &&
1220: (sig_details->sk_flags & SSH_SK_USER_VERIFICATION_REQD) == 0) {
1221: error("public key %s %s signature for %s%s from %.128s "
1222: "port %d rejected: user verification requirement "
1223: "not met ", sshkey_type(key), fp,
1.203 djm 1224: authctxt->valid ? "" : "invalid user ",
1225: authctxt->user, ssh_remote_ipaddr(ssh),
1226: ssh_remote_port(ssh));
1227: ret = SSH_ERR_SIGNATURE_INVALID;
1228: }
1229: }
1.172 djm 1230: auth2_record_key(authctxt, ret == 0, key);
1.136 djm 1231:
1.180 djm 1232: if (key_blobtype == MM_USERKEY)
1233: auth_activate_options(ssh, key_opts);
1.1 provos 1234: monitor_reset_key_state();
1.3 markus 1235:
1.169 markus 1236: sshbuf_reset(m);
1237:
1238: /* encode ret != 0 as positive integer, since we're sending u32 */
1239: encoded_ret = (ret != 0);
1.202 djm 1240: if ((r = sshbuf_put_u32(m, encoded_ret)) != 0 ||
1.205 djm 1241: (r = sshbuf_put_u8(m, sig_details != NULL)) != 0)
1.169 markus 1242: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.202 djm 1243: if (sig_details != NULL) {
1244: if ((r = sshbuf_put_u32(m, sig_details->sk_counter)) != 0 ||
1245: (r = sshbuf_put_u8(m, sig_details->sk_flags)) != 0)
1246: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1247: }
1248: sshkey_sig_details_free(sig_details);
1.59 avsm 1249: mm_request_send(sock, MONITOR_ANS_KEYVERIFY, m);
1.203 djm 1250:
1251: free(sigalg);
1252: free(fp);
1253: sshkey_free(key);
1.1 provos 1254:
1.169 markus 1255: return ret == 0;
1.1 provos 1256: }
1257:
1.2 markus 1258: static void
1.191 djm 1259: mm_record_login(struct ssh *ssh, Session *s, struct passwd *pw)
1.1 provos 1260: {
1261: socklen_t fromlen;
1262: struct sockaddr_storage from;
1263:
1264: /*
1265: * Get IP address of client. If the connection is not a socket, let
1266: * the address be 0.0.0.0.
1267: */
1268: memset(&from, 0, sizeof(from));
1.24 stevesk 1269: fromlen = sizeof(from);
1.191 djm 1270: if (ssh_packet_connection_is_on_socket(ssh)) {
1271: if (getpeername(ssh_packet_get_connection_in(ssh),
1.198 deraadt 1272: (struct sockaddr *)&from, &fromlen) == -1) {
1.1 provos 1273: debug("getpeername: %.100s", strerror(errno));
1.50 markus 1274: cleanup_exit(255);
1.1 provos 1275: }
1276: }
1277: /* Record that there was a login on that tty from the remote host. */
1278: record_login(s->pid, s->tty, pw->pw_name, pw->pw_uid,
1.158 djm 1279: session_get_remote_name_or_ip(ssh, utmp_len, options.use_dns),
1.24 stevesk 1280: (struct sockaddr *)&from, fromlen);
1.1 provos 1281: }
1282:
1283: static void
1284: mm_session_close(Session *s)
1285: {
1.41 djm 1286: debug3("%s: session %d pid %ld", __func__, s->self, (long)s->pid);
1.1 provos 1287: if (s->ttyfd != -1) {
1.86 stevesk 1288: debug3("%s: tty %s ptyfd %d", __func__, s->tty, s->ptyfd);
1.1 provos 1289: session_pty_cleanup2(s);
1290: }
1.96 djm 1291: session_unused(s->self);
1.1 provos 1292: }
1293:
1294: int
1.191 djm 1295: mm_answer_pty(struct ssh *ssh, int sock, struct sshbuf *m)
1.1 provos 1296: {
1.11 mouring 1297: extern struct monitor *pmonitor;
1.1 provos 1298: Session *s;
1.183 markus 1299: int r, res, fd0;
1.1 provos 1300:
1.14 markus 1301: debug3("%s entering", __func__);
1.1 provos 1302:
1.183 markus 1303: sshbuf_reset(m);
1.1 provos 1304: s = session_new();
1305: if (s == NULL)
1306: goto error;
1307: s->authctxt = authctxt;
1308: s->pw = authctxt->pw;
1.11 mouring 1309: s->pid = pmonitor->m_pid;
1.1 provos 1310: res = pty_allocate(&s->ptyfd, &s->ttyfd, s->tty, sizeof(s->tty));
1311: if (res == 0)
1312: goto error;
1313: pty_setowner(authctxt->pw, s->tty);
1314:
1.183 markus 1315: if ((r = sshbuf_put_u32(m, 1)) != 0 ||
1316: (r = sshbuf_put_cstring(m, s->tty)) != 0)
1317: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.1 provos 1318:
1319: /* We need to trick ttyslot */
1320: if (dup2(s->ttyfd, 0) == -1)
1.14 markus 1321: fatal("%s: dup2", __func__);
1.1 provos 1322:
1.191 djm 1323: mm_record_login(ssh, s, authctxt->pw);
1.1 provos 1324:
1325: /* Now we can close the file descriptor again */
1326: close(0);
1.61 dtucker 1327:
1328: /* send messages generated by record_login */
1.183 markus 1329: if ((r = sshbuf_put_stringb(m, loginmsg)) != 0)
1330: fatal("%s: put login message: %s", __func__, ssh_err(r));
1331: sshbuf_reset(loginmsg);
1.61 dtucker 1332:
1333: mm_request_send(sock, MONITOR_ANS_PTY, m);
1334:
1.92 djm 1335: if (mm_send_fd(sock, s->ptyfd) == -1 ||
1336: mm_send_fd(sock, s->ttyfd) == -1)
1337: fatal("%s: send fds failed", __func__);
1.1 provos 1338:
1339: /* make sure nothing uses fd 0 */
1.198 deraadt 1340: if ((fd0 = open(_PATH_DEVNULL, O_RDONLY)) == -1)
1.14 markus 1341: fatal("%s: open(/dev/null): %s", __func__, strerror(errno));
1.1 provos 1342: if (fd0 != 0)
1.14 markus 1343: error("%s: fd0 %d != 0", __func__, fd0);
1.1 provos 1344:
1.212 deraadt 1345: /* slave side of pty is not needed */
1.1 provos 1346: close(s->ttyfd);
1347: s->ttyfd = s->ptyfd;
1348: /* no need to dup() because nobody closes ptyfd */
1349: s->ptymaster = s->ptyfd;
1350:
1.86 stevesk 1351: debug3("%s: tty %s ptyfd %d", __func__, s->tty, s->ttyfd);
1.1 provos 1352:
1353: return (0);
1354:
1355: error:
1356: if (s != NULL)
1357: mm_session_close(s);
1.183 markus 1358: if ((r = sshbuf_put_u32(m, 0)) != 0)
1359: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.59 avsm 1360: mm_request_send(sock, MONITOR_ANS_PTY, m);
1.1 provos 1361: return (0);
1362: }
1363:
1364: int
1.191 djm 1365: mm_answer_pty_cleanup(struct ssh *ssh, int sock, struct sshbuf *m)
1.1 provos 1366: {
1367: Session *s;
1368: char *tty;
1.183 markus 1369: int r;
1.1 provos 1370:
1.14 markus 1371: debug3("%s entering", __func__);
1.1 provos 1372:
1.183 markus 1373: if ((r = sshbuf_get_cstring(m, &tty, NULL)) != 0)
1374: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.1 provos 1375: if ((s = session_by_tty(tty)) != NULL)
1376: mm_session_close(s);
1.183 markus 1377: sshbuf_reset(m);
1.124 djm 1378: free(tty);
1.1 provos 1379: return (0);
1380: }
1381:
1382: int
1.191 djm 1383: mm_answer_term(struct ssh *ssh, int sock, struct sshbuf *req)
1.1 provos 1384: {
1.11 mouring 1385: extern struct monitor *pmonitor;
1.1 provos 1386: int res, status;
1387:
1.14 markus 1388: debug3("%s: tearing down sessions", __func__);
1.1 provos 1389:
1390: /* The child is terminating */
1.173 djm 1391: session_destroy_all(ssh, &mm_session_close);
1.1 provos 1392:
1.11 mouring 1393: while (waitpid(pmonitor->m_pid, &status, 0) == -1)
1.9 markus 1394: if (errno != EINTR)
1395: exit(1);
1.1 provos 1396:
1397: res = WIFEXITED(status) ? WEXITSTATUS(status) : 1;
1398:
1399: /* Terminate process */
1.57 deraadt 1400: exit(res);
1.170 markus 1401: }
1402:
1403: void
1.191 djm 1404: monitor_clear_keystate(struct ssh *ssh, struct monitor *pmonitor)
1.170 markus 1405: {
1406: ssh_clear_newkeys(ssh, MODE_IN);
1407: ssh_clear_newkeys(ssh, MODE_OUT);
1408: sshbuf_free(child_state);
1409: child_state = NULL;
1.1 provos 1410: }
1411:
1412: void
1.191 djm 1413: monitor_apply_keystate(struct ssh *ssh, struct monitor *pmonitor)
1.1 provos 1414: {
1.139 markus 1415: struct kex *kex;
1416: int r;
1417:
1418: debug3("%s: packet_set_state", __func__);
1419: if ((r = ssh_packet_set_state(ssh, child_state)) != 0)
1420: fatal("%s: packet_set_state: %s", __func__, ssh_err(r));
1421: sshbuf_free(child_state);
1422: child_state = NULL;
1423:
1.154 mmcc 1424: if ((kex = ssh->kex) != NULL) {
1.139 markus 1425: /* XXX set callbacks */
1.147 djm 1426: #ifdef WITH_OPENSSL
1.197 djm 1427: kex->kex[KEX_DH_GRP1_SHA1] = kex_gen_server;
1428: kex->kex[KEX_DH_GRP14_SHA1] = kex_gen_server;
1429: kex->kex[KEX_DH_GRP14_SHA256] = kex_gen_server;
1430: kex->kex[KEX_DH_GRP16_SHA512] = kex_gen_server;
1431: kex->kex[KEX_DH_GRP18_SHA512] = kex_gen_server;
1.139 markus 1432: kex->kex[KEX_DH_GEX_SHA1] = kexgex_server;
1433: kex->kex[KEX_DH_GEX_SHA256] = kexgex_server;
1.197 djm 1434: kex->kex[KEX_ECDH_SHA2] = kex_gen_server;
1.147 djm 1435: #endif
1.197 djm 1436: kex->kex[KEX_C25519_SHA256] = kex_gen_server;
1437: kex->kex[KEX_KEM_SNTRUP4591761X25519_SHA512] = kex_gen_server;
1.139 markus 1438: kex->load_host_public_key=&get_hostkey_public_by_type;
1439: kex->load_host_private_key=&get_hostkey_private_by_type;
1440: kex->host_key_index=&get_hostkey_index;
1441: kex->sign = sshd_hostkey_sign;
1442: }
1.1 provos 1443: }
1444:
1.210 djm 1445: /* This function requires careful sanity checking */
1.1 provos 1446:
1447: void
1.192 djm 1448: mm_get_keystate(struct ssh *ssh, struct monitor *pmonitor)
1.1 provos 1449: {
1.14 markus 1450: debug3("%s: Waiting for new keys", __func__);
1.1 provos 1451:
1.139 markus 1452: if ((child_state = sshbuf_new()) == NULL)
1453: fatal("%s: sshbuf_new failed", __func__);
1454: mm_request_receive_expect(pmonitor->m_sendfd, MONITOR_REQ_KEYEXPORT,
1455: child_state);
1456: debug3("%s: GOT new keys", __func__);
1.1 provos 1457: }
1458:
1459:
1460: /* XXX */
1461:
1462: #define FD_CLOSEONEXEC(x) do { \
1.111 djm 1463: if (fcntl(x, F_SETFD, FD_CLOEXEC) == -1) \
1.1 provos 1464: fatal("fcntl(%d, F_SETFD)", x); \
1465: } while (0)
1466:
1.2 markus 1467: static void
1.114 djm 1468: monitor_openfds(struct monitor *mon, int do_logfds)
1.3 markus 1469: {
1.114 djm 1470: int pair[2];
1.171 markus 1471: #ifdef SO_ZEROIZE
1472: int on = 1;
1473: #endif
1.114 djm 1474:
1.1 provos 1475: if (socketpair(AF_UNIX, SOCK_STREAM, 0, pair) == -1)
1.114 djm 1476: fatal("%s: socketpair: %s", __func__, strerror(errno));
1.171 markus 1477: #ifdef SO_ZEROIZE
1.198 deraadt 1478: if (setsockopt(pair[0], SOL_SOCKET, SO_ZEROIZE, &on, sizeof(on)) == -1)
1.171 markus 1479: error("setsockopt SO_ZEROIZE(0): %.100s", strerror(errno));
1.198 deraadt 1480: if (setsockopt(pair[1], SOL_SOCKET, SO_ZEROIZE, &on, sizeof(on)) == -1)
1.171 markus 1481: error("setsockopt SO_ZEROIZE(1): %.100s", strerror(errno));
1482: #endif
1.1 provos 1483: FD_CLOSEONEXEC(pair[0]);
1484: FD_CLOSEONEXEC(pair[1]);
1.114 djm 1485: mon->m_recvfd = pair[0];
1486: mon->m_sendfd = pair[1];
1487:
1488: if (do_logfds) {
1489: if (pipe(pair) == -1)
1490: fatal("%s: pipe: %s", __func__, strerror(errno));
1491: FD_CLOSEONEXEC(pair[0]);
1492: FD_CLOSEONEXEC(pair[1]);
1493: mon->m_log_recvfd = pair[0];
1494: mon->m_log_sendfd = pair[1];
1495: } else
1496: mon->m_log_recvfd = mon->m_log_sendfd = -1;
1.1 provos 1497: }
1498:
1499: #define MM_MEMSIZE 65536
1500:
1501: struct monitor *
1502: monitor_init(void)
1503: {
1504: struct monitor *mon;
1505:
1.75 djm 1506: mon = xcalloc(1, sizeof(*mon));
1.114 djm 1507: monitor_openfds(mon, 1);
1.1 provos 1508:
1509: return mon;
1510: }
1511:
1512: void
1513: monitor_reinit(struct monitor *mon)
1514: {
1.114 djm 1515: monitor_openfds(mon, 0);
1.1 provos 1516: }
1.46 markus 1517:
1518: #ifdef GSSAPI
1519: int
1.191 djm 1520: mm_answer_gss_setup_ctx(struct ssh *ssh, int sock, struct sshbuf *m)
1.46 markus 1521: {
1.59 avsm 1522: gss_OID_desc goid;
1.46 markus 1523: OM_uint32 major;
1.183 markus 1524: size_t len;
1.184 djm 1525: u_char *p;
1.183 markus 1526: int r;
1.46 markus 1527:
1.164 djm 1528: if (!options.gss_authentication)
1529: fatal("%s: GSSAPI authentication not enabled", __func__);
1530:
1.184 djm 1531: if ((r = sshbuf_get_string(m, &p, &len)) != 0)
1.183 markus 1532: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.184 djm 1533: goid.elements = p;
1.59 avsm 1534: goid.length = len;
1.46 markus 1535:
1.59 avsm 1536: major = ssh_gssapi_server_ctx(&gsscontext, &goid);
1.46 markus 1537:
1.124 djm 1538: free(goid.elements);
1.46 markus 1539:
1.183 markus 1540: sshbuf_reset(m);
1541: if ((r = sshbuf_put_u32(m, major)) != 0)
1542: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.46 markus 1543:
1.64 stevesk 1544: mm_request_send(sock, MONITOR_ANS_GSSSETUP, m);
1.46 markus 1545:
1546: /* Now we have a context, enable the step */
1547: monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 1);
1548:
1549: return (0);
1550: }
1551:
1552: int
1.191 djm 1553: mm_answer_gss_accept_ctx(struct ssh *ssh, int sock, struct sshbuf *m)
1.46 markus 1554: {
1555: gss_buffer_desc in;
1556: gss_buffer_desc out = GSS_C_EMPTY_BUFFER;
1.64 stevesk 1557: OM_uint32 major, minor;
1.46 markus 1558: OM_uint32 flags = 0; /* GSI needs this */
1.183 markus 1559: int r;
1.46 markus 1560:
1.164 djm 1561: if (!options.gss_authentication)
1562: fatal("%s: GSSAPI authentication not enabled", __func__);
1563:
1.184 djm 1564: if ((r = ssh_gssapi_get_buffer_desc(m, &in)) != 0)
1.183 markus 1565: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.46 markus 1566: major = ssh_gssapi_accept_ctx(gsscontext, &in, &out, &flags);
1.124 djm 1567: free(in.value);
1.46 markus 1568:
1.183 markus 1569: sshbuf_reset(m);
1570: if ((r = sshbuf_put_u32(m, major)) != 0 ||
1571: (r = sshbuf_put_string(m, out.value, out.length)) != 0 ||
1572: (r = sshbuf_put_u32(m, flags)) != 0)
1573: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.59 avsm 1574: mm_request_send(sock, MONITOR_ANS_GSSSTEP, m);
1.46 markus 1575:
1576: gss_release_buffer(&minor, &out);
1577:
1.64 stevesk 1578: if (major == GSS_S_COMPLETE) {
1.46 markus 1579: monitor_permit(mon_dispatch, MONITOR_REQ_GSSSTEP, 0);
1580: monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
1.52 markus 1581: monitor_permit(mon_dispatch, MONITOR_REQ_GSSCHECKMIC, 1);
1.46 markus 1582: }
1583: return (0);
1584: }
1585:
1586: int
1.191 djm 1587: mm_answer_gss_checkmic(struct ssh *ssh, int sock, struct sshbuf *m)
1.52 markus 1588: {
1589: gss_buffer_desc gssbuf, mic;
1590: OM_uint32 ret;
1.184 djm 1591: int r;
1.54 djm 1592:
1.164 djm 1593: if (!options.gss_authentication)
1594: fatal("%s: GSSAPI authentication not enabled", __func__);
1595:
1.184 djm 1596: if ((r = ssh_gssapi_get_buffer_desc(m, &gssbuf)) != 0 ||
1597: (r = ssh_gssapi_get_buffer_desc(m, &mic)) != 0)
1.183 markus 1598: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.54 djm 1599:
1.52 markus 1600: ret = ssh_gssapi_checkmic(gsscontext, &gssbuf, &mic);
1.54 djm 1601:
1.124 djm 1602: free(gssbuf.value);
1603: free(mic.value);
1.54 djm 1604:
1.183 markus 1605: sshbuf_reset(m);
1606: if ((r = sshbuf_put_u32(m, ret)) != 0)
1607: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.54 djm 1608:
1.59 avsm 1609: mm_request_send(sock, MONITOR_ANS_GSSCHECKMIC, m);
1.54 djm 1610:
1.52 markus 1611: if (!GSS_ERROR(ret))
1612: monitor_permit(mon_dispatch, MONITOR_REQ_GSSUSEROK, 1);
1.54 djm 1613:
1.52 markus 1614: return (0);
1615: }
1616:
1617: int
1.191 djm 1618: mm_answer_gss_userok(struct ssh *ssh, int sock, struct sshbuf *m)
1.46 markus 1619: {
1.184 djm 1620: int r, authenticated;
1.172 djm 1621: const char *displayname;
1.164 djm 1622:
1623: if (!options.gss_authentication)
1624: fatal("%s: GSSAPI authentication not enabled", __func__);
1.46 markus 1625:
1626: authenticated = authctxt->valid && ssh_gssapi_userok(authctxt->user);
1627:
1.183 markus 1628: sshbuf_reset(m);
1629: if ((r = sshbuf_put_u32(m, authenticated)) != 0)
1630: fatal("%s: buffer error: %s", __func__, ssh_err(r));
1.46 markus 1631:
1632: debug3("%s: sending result %d", __func__, authenticated);
1.59 avsm 1633: mm_request_send(sock, MONITOR_ANS_GSSUSEROK, m);
1.46 markus 1634:
1.64 stevesk 1635: auth_method = "gssapi-with-mic";
1.172 djm 1636:
1637: if ((displayname = ssh_gssapi_displayname()) != NULL)
1638: auth2_record_info(authctxt, "%s", displayname);
1.46 markus 1639:
1640: /* Monitor loop will terminate if authenticated */
1641: return (authenticated);
1642: }
1643: #endif /* GSSAPI */
1.100 djm 1644:
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