1 /*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 2008 Isilon Inc http://www.isilon.com/
5 * Authors: Doug Rabson <dfr@rabson.org>
6 * Developed with Red Inc: Alfred Perlstein <alfred@freebsd.org>
7 * Copyright (c) 2025 Gleb Smirnoff <glebius@FreeBSD.org>
8 *
9 * Redistribution and use in source and binary forms, with or without
10 * modification, are permitted provided that the following conditions
11 * are met:
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in the
16 * documentation and/or other materials provided with the distribution.
17 *
18 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
19 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
20 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
21 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
22 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
23 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
24 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
25 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
26 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
27 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
28 * SUCH DAMAGE.
29 */
30
31 /*
32 * Extensively modified from /usr/src/usr.sbin/gssd.c r344402 for
33 * the server side of kernel RPC-over-TLS by Rick Macklem.
34 */
35
36 #include <sys/types.h>
37 #include <sys/linker.h>
38 #include <sys/module.h>
39 #include <sys/queue.h>
40 #include <sys/sysctl.h>
41 #include <sys/syslog.h>
42 #include <assert.h>
43 #include <err.h>
44 #include <getopt.h>
45 #include <libutil.h>
46 #include <netdb.h>
47 #include <pthread.h>
48 #include <pwd.h>
49 #include <stdbool.h>
50 #include <unistd.h>
51
52 #include <rpc/rpc.h>
53 #include <rpc/rpc_com.h>
54 #include <rpc/rpcsec_tls.h>
55
56 #include <openssl/opensslconf.h>
57 #include <openssl/bio.h>
58 #include <openssl/ssl.h>
59 #include <openssl/err.h>
60 #include <openssl/x509v3.h>
61
62 #include "rpctlssd.h"
63 #include "rpc.tlscommon.h"
64
65 #ifndef _PATH_CERTANDKEY
66 #define _PATH_CERTANDKEY "/etc/rpc.tlsservd/"
67 #endif
68 #ifndef _PATH_RPCTLSSDPID
69 #define _PATH_RPCTLSSDPID "/var/run/rpc.tlsservd.pid"
70 #endif
71 #ifndef _PREFERRED_CIPHERS
72 #define _PREFERRED_CIPHERS "AES128-GCM-SHA256"
73 #endif
74
75 /* Global variables also used by rpc.tlscommon.c. */
76 int rpctls_debug_level;
77 bool rpctls_verbose;
78 SSL_CTX *rpctls_ctx = NULL;
79 const char *rpctls_verify_cafile = NULL;
80 const char *rpctls_verify_capath = NULL;
81 char *rpctls_crlfile = NULL;
82 bool rpctls_gothup = false;
83
84 static SVCXPRT *xprt;
85 static pthread_key_t xidkey;
86 struct ssl_list rpctls_ssllist;
87 static pthread_rwlock_t rpctls_rwlock;
88 static u_int rpctls_nthreads = 0;
89 static pthread_mutex_t rpctls_mtx;
90 static pthread_cond_t rpctls_cv;
91
92 static struct pidfh *rpctls_pfh = NULL;
93 static bool rpctls_do_mutual = false;
94 static const char *rpctls_certdir = _PATH_CERTANDKEY;
95 static bool rpctls_comparehost = false;
96 static unsigned int rpctls_wildcard = X509_CHECK_FLAG_NO_WILDCARDS;
97 static bool rpctls_cnuser = false;
98 static char *rpctls_dnsname;
99 static const char *rpctls_cnuseroid = "1.3.6.1.4.1.2238.1.1.1";
100 static const char *rpctls_ciphers = NULL;
101 static int rpctls_mintls = TLS1_3_VERSION;
102 static u_int rpctls_maxthreads;
103
104 static void rpctls_cleanup_term(int sig);
105 static SSL_CTX *rpctls_setup_ssl(const char *certdir);
106 static SSL *rpctls_server(SSL_CTX *ctx, int s,
107 uint32_t *flags, uint32_t *uidp,
108 int *ngrps, uint32_t *gidp, X509 **certp);
109 static int rpctls_cnname(X509 *cert, uint32_t *uidp,
110 int *ngrps, uint32_t *gidp);
111 static char *rpctls_getdnsname(char *dnsname);
112 static void rpctls_huphandler(int sig __unused);
113
114 extern void rpctlssd_2(struct svc_req *rqstp, SVCXPRT *transp);
115
dummy_thread(void * v __unused)116 static void *dummy_thread(void *v __unused) { return (NULL); }
117
118 static struct option longopts[] = {
119 { "allowtls1_2", no_argument, NULL, '2' },
120 { "ciphers", required_argument, NULL, 'C' },
121 { "certdir", required_argument, NULL, 'D' },
122 { "debuglevel", no_argument, NULL, 'd' },
123 { "checkhost", no_argument, NULL, 'h' },
124 { "verifylocs", required_argument, NULL, 'l' },
125 { "mutualverf", no_argument, NULL, 'm' },
126 { "maxthreads", required_argument, NULL, 'N' },
127 { "domain", required_argument, NULL, 'n' },
128 { "verifydir", required_argument, NULL, 'p' },
129 { "crl", required_argument, NULL, 'r' },
130 { "certuser", no_argument, NULL, 'u' },
131 { "verbose", no_argument, NULL, 'v' },
132 { "multiwild", no_argument, NULL, 'W' },
133 { "singlewild", no_argument, NULL, 'w' },
134 { NULL, 0, NULL, 0 }
135 };
136
137 int
main(int argc,char ** argv)138 main(int argc, char **argv)
139 {
140 int ch;
141 char hostname[MAXHOSTNAMELEN + 2];
142 pid_t otherpid;
143 pthread_t tid;
144 bool tls_enable;
145 size_t tls_enable_len;
146 u_int ncpu;
147
148 /* Check that another rpctlssd isn't already running. */
149 rpctls_pfh = pidfile_open(_PATH_RPCTLSSDPID, 0600, &otherpid);
150 if (rpctls_pfh == NULL) {
151 if (errno == EEXIST)
152 errx(1, "rpctlssd already running, pid: %d.", otherpid);
153 warn("cannot open or create pidfile");
154 }
155
156 /* Check to see that the ktls is enabled. */
157 tls_enable_len = sizeof(tls_enable);
158 if (sysctlbyname("kern.ipc.tls.enable", &tls_enable, &tls_enable_len,
159 NULL, 0) != 0 || !tls_enable)
160 errx(1, "Kernel TLS not enabled");
161
162 /* Set the dns name for the server. */
163 rpctls_dnsname = rpctls_getdnsname(hostname);
164 if (rpctls_dnsname == NULL) {
165 strcpy(hostname, "@default.domain");
166 rpctls_dnsname = hostname;
167 }
168
169 rpctls_verbose = false;
170 ncpu = (u_int)sysconf(_SC_NPROCESSORS_ONLN);
171 rpctls_maxthreads = ncpu > 1 ? ncpu / 2 : 1;
172
173 while ((ch = getopt_long(argc, argv, "2C:D:dhl:N:n:mp:r:uvWw", longopts,
174 NULL)) != -1) {
175 switch (ch) {
176 case '2':
177 rpctls_mintls = TLS1_2_VERSION;
178 break;
179 case 'C':
180 rpctls_ciphers = optarg;
181 break;
182 case 'D':
183 rpctls_certdir = optarg;
184 break;
185 case 'd':
186 rpctls_debug_level++;
187 break;
188 case 'h':
189 rpctls_comparehost = true;
190 break;
191 case 'l':
192 rpctls_verify_cafile = optarg;
193 break;
194 case 'm':
195 rpctls_do_mutual = true;
196 break;
197 case 'N':
198 rpctls_maxthreads = atoi(optarg);
199 if (rpctls_maxthreads < 1 || rpctls_maxthreads > ncpu)
200 errx(1, "maximum threads must be between 1 and "
201 "number of CPUs (%d)", ncpu);
202 break;
203 case 'n':
204 hostname[0] = '@';
205 strlcpy(&hostname[1], optarg, MAXHOSTNAMELEN + 1);
206 rpctls_dnsname = hostname;
207 break;
208 case 'p':
209 rpctls_verify_capath = optarg;
210 break;
211 case 'r':
212 rpctls_crlfile = optarg;
213 break;
214 case 'u':
215 rpctls_cnuser = true;
216 break;
217 case 'v':
218 rpctls_verbose = true;
219 break;
220 case 'W':
221 if (rpctls_wildcard != X509_CHECK_FLAG_NO_WILDCARDS)
222 errx(1, "options -w and -W are mutually "
223 "exclusive");
224 rpctls_wildcard = X509_CHECK_FLAG_MULTI_LABEL_WILDCARDS;
225 break;
226 case 'w':
227 if (rpctls_wildcard != X509_CHECK_FLAG_NO_WILDCARDS)
228 errx(1, "options -w and -W are mutually "
229 "exclusive");
230 rpctls_wildcard = 0;
231 break;
232 default:
233 fprintf(stderr, "usage: %s "
234 "[-2/--allowtls1_2] "
235 "[-C/--ciphers available_ciphers] "
236 "[-D/--certdir certdir] [-d/--debuglevel] "
237 "[-h/--checkhost] "
238 "[-l/--verifylocs CAfile] [-m/--mutualverf] "
239 "[-n/--domain domain_name] "
240 "[-p/--verifydir CApath] [-r/--crl CRLfile] "
241 "[-u/--certuser] [-v/--verbose] [-W/--multiwild] "
242 "[-w/--singlewild]\n", argv[0]);
243 exit(1);
244 }
245 }
246 if (rpctls_do_mutual && rpctls_verify_cafile == NULL &&
247 rpctls_verify_capath == NULL)
248 errx(1, "-m requires the -l <CAfile> and/or "
249 "-p <CApath> options");
250 if (rpctls_comparehost && (!rpctls_do_mutual ||
251 (rpctls_verify_cafile == NULL && rpctls_verify_capath == NULL)))
252 errx(1, "-h requires the -m plus the "
253 "-l <CAfile> and/or -p <CApath> options");
254 if (!rpctls_comparehost && rpctls_wildcard !=
255 X509_CHECK_FLAG_NO_WILDCARDS)
256 errx(1, "The -w or -W options require the -h option");
257 if (rpctls_cnuser && (!rpctls_do_mutual ||
258 (rpctls_verify_cafile == NULL && rpctls_verify_capath == NULL)))
259 errx(1, "-u requires the -m plus the "
260 "-l <CAfile> and/or -p <CApath> options");
261
262 if (modfind("krpc") < 0) {
263 /* Not present in kernel, try loading it */
264 if (kldload("krpc") < 0 || modfind("krpc") < 0)
265 errx(1, "Kernel RPC is not available");
266 }
267 signal(SIGPIPE, SIG_IGN);
268 signal(SIGHUP, rpctls_huphandler);
269 signal(SIGTERM, rpctls_cleanup_term);
270
271 if (rpctls_debug_level == 0 && daemon(0, 0) != 0)
272 err(1, "Can't daemonize");
273 pidfile_write(rpctls_pfh);
274
275 /*
276 * XXX: Push libc internal state into threaded mode before creating
277 * the threaded svc_nl xprt.
278 */
279 (void)pthread_create(&tid, NULL, dummy_thread, NULL);
280 (void)pthread_join(tid, NULL);
281 if ((xprt = svc_nl_create("tlsserv")) == NULL) {
282 if (rpctls_debug_level == 0) {
283 syslog(LOG_ERR,
284 "Can't create transport for local rpctlssd socket");
285 exit(1);
286 }
287 err(1, "Can't create transport for local rpctlssd socket");
288 }
289 if (!SVC_CONTROL(xprt, SVCNL_GET_XIDKEY, &xidkey))
290 err(1, "Failed to obtain pthread key for xid from svc_nl");
291 if (!svc_reg(xprt, RPCTLSSD, RPCTLSSDVERS, rpctlssd_2, NULL)) {
292 if (rpctls_debug_level == 0) {
293 syslog(LOG_ERR,
294 "Can't register service for local rpctlssd socket");
295 exit(1);
296 }
297 err(1, "Can't register service for local rpctlssd socket");
298 }
299
300 rpctls_ctx = rpctls_setup_ssl(rpctls_certdir);
301 if (rpctls_ctx == NULL) {
302 if (rpctls_debug_level == 0) {
303 syslog(LOG_ERR, "Can't create SSL context");
304 exit(1);
305 }
306 err(1, "Can't create SSL context");
307 }
308 rpctls_gothup = false;
309 pthread_rwlock_init(&rpctls_rwlock, NULL);
310 pthread_mutex_init(&rpctls_mtx, NULL);
311 pthread_cond_init(&rpctls_cv, NULL);
312 LIST_INIT(&rpctls_ssllist);
313
314 rpctls_svc_run();
315
316 SSL_CTX_free(rpctls_ctx);
317 return (0);
318 }
319
320 bool_t
rpctlssd_null_2_svc(__unused void * argp,__unused void * result,__unused struct svc_req * rqstp)321 rpctlssd_null_2_svc(__unused void *argp, __unused void *result,
322 __unused struct svc_req *rqstp)
323 {
324
325 rpctls_verbose_out("rpctlssd_null_svc: done\n");
326 return (TRUE);
327 }
328
329 /*
330 * To parallelize SSL handshakes we will launch a thread per handshake. Thread
331 * creation/destruction shall be order(s) of magnitude cheaper than a crypto
332 * handshake, so we are not keeping a pool of workers here.
333 *
334 * Marrying rpc(3) and pthread(3):
335 *
336 * Normally the rpcgen(1) generated rpctlssd_V() calls rpctlssd_connect_V_svc(),
337 * and the latter processes the RPC all the way to the end and returns a TRUE
338 * value and populates the result. The generated code immediately calls
339 * svc_sendreply() transmitting the result back.
340 *
341 * We will make a private copy of arguments and return FALSE. Then it is our
342 * obligation to call svc_sendreply() once we do the work in the thread.
343 */
344
345 static void * rpctlssd_connect_thread(void *);
346 struct rpctlssd_connect_thread_ctx {
347 struct rpctlssd_connect_arg arg;
348 uint32_t xid;
349 };
350
351 bool_t
rpctlssd_connect_2_svc(struct rpctlssd_connect_arg * argp,struct rpctlssd_connect_res * result __unused,struct svc_req * rqstp)352 rpctlssd_connect_2_svc(struct rpctlssd_connect_arg *argp,
353 struct rpctlssd_connect_res *result __unused, struct svc_req *rqstp)
354 {
355 struct rpctlssd_connect_thread_ctx *ctx;
356 pthread_t tid;
357
358 assert(rqstp->rq_xprt == xprt);
359
360 ctx = malloc(sizeof(*ctx));
361 memcpy(&ctx->arg, argp, sizeof(ctx->arg));
362 ctx->xid = *(uint32_t *)pthread_getspecific(xidkey);
363
364 pthread_mutex_lock(&rpctls_mtx);
365 while (rpctls_nthreads >= rpctls_maxthreads)
366 pthread_cond_wait(&rpctls_cv, &rpctls_mtx);
367 rpctls_nthreads++;
368 pthread_mutex_unlock(&rpctls_mtx);
369
370 rpctls_verbose_out("rpctlsd_connect_svc: xid %u thread %u\n",
371 ctx->xid, rpctls_nthreads);
372
373 if (pthread_create(&tid, NULL, rpctlssd_connect_thread, ctx) != 0)
374 warn("failed to start handshake thread");
375
376 /* Intentionally, so that RPC generated code doesn't try to reply. */
377 return (FALSE);
378 }
379
380 static void *
rpctlssd_connect_thread(void * v)381 rpctlssd_connect_thread(void *v)
382 {
383 struct rpctlssd_connect_thread_ctx *ctx = v;
384 struct rpctlssd_connect_res result;
385 uint64_t socookie;
386 int ngrps, s;
387 SSL *ssl;
388 uint32_t flags;
389 struct ssl_entry *newslp;
390 uint32_t xid, uid;
391 uint32_t *gidp;
392 X509 *cert;
393
394 socookie = ctx->arg.socookie;
395 xid = ctx->xid;
396 free(ctx);
397 ctx = NULL;
398 pthread_detach(pthread_self());
399
400 if (pthread_setspecific(xidkey, &xid) != 0) {
401 rpctls_verbose_out("rpctlssd_connect_svc: pthread_setspecific "
402 "failed\n");
403 goto out;
404 }
405
406 /* Get the socket fd from the kernel. */
407 s = rpctls_syscall(socookie);
408 if (s < 0) {
409 rpctls_verbose_out("rpctlssd_connect_svc: rpctls_syscall "
410 "accept failed\n");
411 goto out;
412 }
413
414 /* Do the server side of a TLS handshake. */
415 gidp = calloc(NGROUPS, sizeof(*gidp));
416 ssl = rpctls_server(rpctls_ctx, s, &flags, &uid, &ngrps, gidp, &cert);
417 if (ssl == NULL) {
418 free(gidp);
419 rpctls_verbose_out("rpctlssd_connect_svc: ssl "
420 "accept failed\n");
421 /*
422 * For RPC-over-TLS, this upcall is expected
423 * to close off the socket upon handshake failure.
424 */
425 close(s);
426 goto out;
427 } else {
428 rpctls_verbose_out("rpctlssd_connect_svc: "
429 "succeeded flags=0x%x\n", flags);
430 if ((flags & RPCTLS_FLAGS_CERTUSER) != 0)
431 result = (struct rpctlssd_connect_res){
432 .flags = flags,
433 .uid = uid,
434 .gid.gid_len = ngrps,
435 .gid.gid_val = gidp,
436 };
437 else
438 result = (struct rpctlssd_connect_res){
439 .flags = flags,
440 .uid = 0,
441 .gid.gid_len = 0,
442 .gid.gid_val = gidp,
443 };
444 }
445
446 /* Maintain list of all current SSL *'s */
447 newslp = malloc(sizeof(*newslp));
448 newslp->ssl = ssl;
449 newslp->s = s;
450 newslp->shutoff = false;
451 newslp->cookie = socookie;
452 newslp->cert = cert;
453 pthread_rwlock_wrlock(&rpctls_rwlock);
454 LIST_INSERT_HEAD(&rpctls_ssllist, newslp, next);
455 pthread_rwlock_unlock(&rpctls_rwlock);
456
457 if (!svc_sendreply(xprt, (xdrproc_t)xdr_rpctlssd_connect_res, &result))
458 svcerr_systemerr(xprt);
459
460 free(result.gid.gid_val);
461 rpctls_verbose_out("rpctlsd_connect_svc: xid %u: thread finished\n",
462 xid);
463
464 out:
465 pthread_mutex_lock(&rpctls_mtx);
466 if (rpctls_nthreads-- >= rpctls_maxthreads) {
467 pthread_mutex_unlock(&rpctls_mtx);
468 pthread_cond_signal(&rpctls_cv);
469 } else
470 pthread_mutex_unlock(&rpctls_mtx);
471 return (NULL);
472 }
473
474 bool_t
rpctlssd_handlerecord_2_svc(struct rpctlssd_handlerecord_arg * argp,struct rpctlssd_handlerecord_res * result,__unused struct svc_req * rqstp)475 rpctlssd_handlerecord_2_svc(struct rpctlssd_handlerecord_arg *argp,
476 struct rpctlssd_handlerecord_res *result, __unused struct svc_req *rqstp)
477 {
478 struct ssl_entry *slp;
479 int ret;
480 char junk;
481
482 pthread_rwlock_rdlock(&rpctls_rwlock);
483 LIST_FOREACH(slp, &rpctls_ssllist, next)
484 if (slp->cookie == argp->socookie)
485 break;
486 pthread_rwlock_unlock(&rpctls_rwlock);
487
488 if (slp != NULL) {
489 rpctls_verbose_out("rpctlssd_handlerecord fd=%d\n",
490 slp->s);
491 /*
492 * An SSL_read() of 0 bytes should fail, but it should
493 * handle the non-application data record before doing so.
494 */
495 ret = SSL_read(slp->ssl, &junk, 0);
496 if (ret <= 0) {
497 /* Check to see if this was a close alert. */
498 ret = SSL_get_shutdown(slp->ssl);
499 if ((ret & (SSL_SENT_SHUTDOWN |
500 SSL_RECEIVED_SHUTDOWN)) == SSL_RECEIVED_SHUTDOWN)
501 SSL_shutdown(slp->ssl);
502 } else {
503 if (rpctls_debug_level == 0)
504 syslog(LOG_ERR, "SSL_read returned %d", ret);
505 else
506 fprintf(stderr, "SSL_read returned %d\n", ret);
507 }
508 result->reterr = RPCTLSERR_OK;
509 } else
510 result->reterr = RPCTLSERR_NOSSL;
511 return (TRUE);
512 }
513
514 bool_t
rpctlssd_disconnect_2_svc(struct rpctlssd_disconnect_arg * argp,struct rpctlssd_disconnect_res * result,__unused struct svc_req * rqstp)515 rpctlssd_disconnect_2_svc(struct rpctlssd_disconnect_arg *argp,
516 struct rpctlssd_disconnect_res *result, __unused struct svc_req *rqstp)
517 {
518 struct ssl_entry *slp;
519 int ret;
520
521 pthread_rwlock_wrlock(&rpctls_rwlock);
522 LIST_FOREACH(slp, &rpctls_ssllist, next)
523 if (slp->cookie == argp->socookie) {
524 LIST_REMOVE(slp, next);
525 break;
526 }
527 pthread_rwlock_unlock(&rpctls_rwlock);
528
529 if (slp != NULL) {
530 rpctls_verbose_out("rpctlssd_disconnect fd=%d closed\n",
531 slp->s);
532 if (!slp->shutoff) {
533 ret = SSL_get_shutdown(slp->ssl);
534 /*
535 * Do an SSL_shutdown() unless a close alert has
536 * already been sent.
537 */
538 if ((ret & SSL_SENT_SHUTDOWN) == 0)
539 SSL_shutdown(slp->ssl);
540 }
541 SSL_free(slp->ssl);
542 if (slp->cert != NULL)
543 X509_free(slp->cert);
544 /*
545 * For RPC-over-TLS, this upcall is expected
546 * to close off the socket.
547 */
548 if (!slp->shutoff)
549 shutdown(slp->s, SHUT_WR);
550 close(slp->s);
551 free(slp);
552 result->reterr = RPCTLSERR_OK;
553 } else
554 result->reterr = RPCTLSERR_NOCLOSE;
555 return (TRUE);
556 }
557
558 int
rpctlssd_2_freeresult(__unused SVCXPRT * transp,xdrproc_t xdr_result __unused,caddr_t result __unused)559 rpctlssd_2_freeresult(__unused SVCXPRT *transp, xdrproc_t xdr_result __unused,
560 caddr_t result __unused)
561 {
562 return (TRUE);
563 }
564
565 /*
566 * cleanup_term() called via SIGTERM (or SIGCHLD if a child dies).
567 */
568 static void
rpctls_cleanup_term(int sig __unused)569 rpctls_cleanup_term(int sig __unused)
570 {
571 struct ssl_entry *slp;
572
573 LIST_FOREACH(slp, &rpctls_ssllist, next)
574 shutdown(slp->s, SHUT_RD);
575 SSL_CTX_free(rpctls_ctx);
576 EVP_cleanup();
577 pidfile_remove(rpctls_pfh);
578
579 exit(0);
580 }
581
582 /* Allow the handshake to proceed. */
583 static int
rpctls_verify_callback(__unused int preverify_ok,__unused X509_STORE_CTX * x509_ctx)584 rpctls_verify_callback(__unused int preverify_ok,
585 __unused X509_STORE_CTX *x509_ctx)
586 {
587
588 return (1);
589 }
590
591 static SSL_CTX *
rpctls_setup_ssl(const char * certdir)592 rpctls_setup_ssl(const char *certdir)
593 {
594 SSL_CTX *ctx;
595 char path[PATH_MAX];
596 size_t len, rlen;
597 int ret;
598
599 ctx = SSL_CTX_new(TLS_server_method());
600 if (ctx == NULL) {
601 rpctls_verbose_out("rpctls_setup_ssl: SSL_CTX_new failed\n");
602 return (NULL);
603 }
604
605 if (rpctls_ciphers != NULL) {
606 /*
607 * Set available ciphers, since KERN_TLS only supports a
608 * few of them. Normally, not doing this should be ok,
609 * since the library defaults will work.
610 */
611 ret = SSL_CTX_set_ciphersuites(ctx, rpctls_ciphers);
612 if (ret == 0) {
613 rpctls_verbose_out("rpctls_setup_ssl: "
614 "SSL_CTX_set_ciphersuites failed: %s\n",
615 rpctls_ciphers);
616 SSL_CTX_free(ctx);
617 return (NULL);
618 }
619 }
620
621 ret = SSL_CTX_set_min_proto_version(ctx, rpctls_mintls);
622 if (ret == 0) {
623 rpctls_verbose_out("rpctls_setup_ssl: "
624 "SSL_CTX_set_min_proto_version failed\n");
625 SSL_CTX_free(ctx);
626 return (NULL);
627 }
628 ret = SSL_CTX_set_max_proto_version(ctx, TLS1_3_VERSION);
629 if (ret == 0) {
630 rpctls_verbose_out("rpctls_setup_ssl: "
631 "SSL_CTX_set_max_proto_version failed\n");
632 SSL_CTX_free(ctx);
633 return (NULL);
634 }
635
636 /* Get the cert.pem and certkey.pem files from the directory certdir. */
637 len = strlcpy(path, certdir, sizeof(path));
638 rlen = sizeof(path) - len;
639 if (strlcpy(&path[len], "cert.pem", rlen) != 8) {
640 SSL_CTX_free(ctx);
641 return (NULL);
642 }
643 ret = SSL_CTX_use_certificate_file(ctx, path, SSL_FILETYPE_PEM);
644 if (ret != 1) {
645 rpctls_verbose_out("rpctls_setup_ssl: can't use certificate "
646 "file path=%s ret=%d\n", path, ret);
647 SSL_CTX_free(ctx);
648 return (NULL);
649 }
650 if (strlcpy(&path[len], "certkey.pem", rlen) != 11) {
651 SSL_CTX_free(ctx);
652 return (NULL);
653 }
654 ret = SSL_CTX_use_PrivateKey_file(ctx, path, SSL_FILETYPE_PEM);
655 if (ret != 1) {
656 rpctls_verbose_out("rpctls_setup_ssl: Can't use private "
657 "key path=%s ret=%d\n", path, ret);
658 SSL_CTX_free(ctx);
659 return (NULL);
660 }
661
662 /* Set Mutual authentication, as required. */
663 if (rpctls_do_mutual) {
664 if (rpctls_verify_cafile != NULL ||
665 rpctls_verify_capath != NULL) {
666 if (rpctls_crlfile != NULL) {
667 ret = rpctls_loadcrlfile(ctx);
668 if (ret == 0) {
669 rpctls_verbose_out("rpctls_setup_ssl:"
670 " Load CRLfile failed\n");
671 SSL_CTX_free(ctx);
672 return (NULL);
673 }
674 }
675 #if OPENSSL_VERSION_NUMBER >= 0x30000000
676 ret = 1;
677 if (rpctls_verify_cafile != NULL)
678 ret = SSL_CTX_load_verify_file(ctx,
679 rpctls_verify_cafile);
680 if (ret != 0 && rpctls_verify_capath != NULL)
681 ret = SSL_CTX_load_verify_dir(ctx,
682 rpctls_verify_capath);
683 #else
684 ret = SSL_CTX_load_verify_locations(ctx,
685 rpctls_verify_cafile, rpctls_verify_capath);
686 #endif
687 if (ret == 0) {
688 rpctls_verbose_out("rpctls_setup_ssl: "
689 "Can't load verify locations\n");
690 SSL_CTX_free(ctx);
691 return (NULL);
692 }
693 if (rpctls_verify_cafile != NULL)
694 SSL_CTX_set_client_CA_list(ctx,
695 SSL_load_client_CA_file(
696 rpctls_verify_cafile));
697 }
698 SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER,
699 rpctls_verify_callback);
700 }
701 #ifdef SSL_OP_ENABLE_KTLS
702 SSL_CTX_set_options(ctx, SSL_OP_ENABLE_KTLS);
703 #endif
704 #ifdef SSL_MODE_NO_KTLS_TX
705 SSL_CTX_clear_mode(ctx, SSL_MODE_NO_KTLS_TX | SSL_MODE_NO_KTLS_RX);
706 #endif
707 return (ctx);
708 }
709
710 static SSL *
rpctls_server(SSL_CTX * ctx,int s,uint32_t * flags,uint32_t * uidp,int * ngrps,uint32_t * gidp,X509 ** certp)711 rpctls_server(SSL_CTX *ctx, int s, uint32_t *flags, uint32_t *uidp,
712 int *ngrps, uint32_t *gidp, X509 **certp)
713 {
714 SSL *ssl;
715 X509 *cert;
716 struct sockaddr *sad;
717 struct sockaddr_storage ad;
718 char hostnam[NI_MAXHOST];
719 int gethostret, ret;
720 char *cp, *cp2;
721 long verfret;
722
723 *flags = 0;
724 *certp = NULL;
725 sad = (struct sockaddr *)&ad;
726 ssl = SSL_new(ctx);
727 if (ssl == NULL) {
728 rpctls_verbose_out("rpctls_server: SSL_new failed\n");
729 return (NULL);
730 }
731 if (SSL_set_fd(ssl, s) != 1) {
732 rpctls_verbose_out("rpctls_server: SSL_set_fd failed\n");
733 SSL_free(ssl);
734 return (NULL);
735 }
736 ret = SSL_accept(ssl);
737 if (ret != 1) {
738 rpctls_verbose_out("rpctls_server: SSL_accept "
739 "failed ret=%d\n", ret);
740 SSL_free(ssl);
741 return (NULL);
742 }
743 *flags |= RPCTLS_FLAGS_HANDSHAKE;
744 if (rpctls_verbose) {
745 gethostret = rpctls_gethost(s, sad, hostnam, sizeof(hostnam));
746 if (gethostret == 0)
747 hostnam[0] = '\0';
748 rpctls_verbose_out("rpctls_server: SSL handshake ok for host %s"
749 " <%s %s>\n", hostnam, SSL_get_version(ssl),
750 SSL_get_cipher(ssl));
751 }
752 if (rpctls_do_mutual) {
753 #if OPENSSL_VERSION_NUMBER >= 0x30000000
754 cert = SSL_get1_peer_certificate(ssl);
755 #else
756 cert = SSL_get_peer_certificate(ssl);
757 #endif
758 if (cert != NULL) {
759 if (!rpctls_verbose) {
760 gethostret = rpctls_gethost(s, sad, hostnam,
761 sizeof(hostnam));
762 if (gethostret == 0)
763 hostnam[0] = '\0';
764 }
765 cp2 = X509_NAME_oneline(
766 X509_get_subject_name(cert), NULL, 0);
767 *flags |= RPCTLS_FLAGS_GOTCERT;
768 verfret = SSL_get_verify_result(ssl);
769 if (verfret != X509_V_OK) {
770 cp = X509_NAME_oneline(
771 X509_get_issuer_name(cert), NULL, 0);
772 if (rpctls_debug_level == 0)
773 syslog(LOG_INFO | LOG_DAEMON,
774 "rpctls_server: client IP %s "
775 "issuerName=%s subjectName=%s"
776 " verify failed %s\n", hostnam,
777 cp, cp2,
778 X509_verify_cert_error_string(
779 verfret));
780 else
781 fprintf(stderr,
782 "rpctls_server: client IP %s "
783 "issuerName=%s subjectName=%s"
784 " verify failed %s\n", hostnam,
785 cp, cp2,
786 X509_verify_cert_error_string(
787 verfret));
788 }
789 if (verfret ==
790 X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT ||
791 verfret == X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN)
792 *flags |= RPCTLS_FLAGS_SELFSIGNED;
793 else if (verfret == X509_V_OK) {
794 if (rpctls_comparehost) {
795 ret = 0;
796 if (gethostret != 0)
797 ret = rpctls_checkhost(sad,
798 cert, rpctls_wildcard);
799 if (ret != 1) {
800 *flags |=
801 RPCTLS_FLAGS_DISABLED;
802 rpctls_verbose_out(
803 "rpctls_server: "
804 "checkhost "
805 "failed\n");
806 }
807 }
808 if (rpctls_cnuser) {
809 ret = rpctls_cnname(cert, uidp,
810 ngrps, gidp);
811 if (ret != 0)
812 *flags |= RPCTLS_FLAGS_CERTUSER;
813 }
814 *flags |= RPCTLS_FLAGS_VERIFIED;
815 *certp = cert;
816 cert = NULL;
817 }
818 if (cert != NULL)
819 X509_free(cert);
820 } else
821 rpctls_verbose_out("rpctls_server: "
822 "No peer certificate\n");
823 }
824
825 /* Check to see that ktls is working for the connection. */
826 ret = BIO_get_ktls_send(SSL_get_wbio(ssl));
827 rpctls_verbose_out("rpctls_server: BIO_get_ktls_send=%d\n", ret);
828 if (ret != 0) {
829 ret = BIO_get_ktls_recv(SSL_get_rbio(ssl));
830 rpctls_verbose_out("rpctls_server: BIO_get_ktls_recv=%d\n",
831 ret);
832 }
833 if (ret == 0) {
834 if (rpctls_debug_level == 0)
835 syslog(LOG_ERR, "ktls not working");
836 else
837 fprintf(stderr, "ktls not working\n");
838 /*
839 * The handshake has completed, so all that can be
840 * done is disable the connection.
841 */
842 *flags |= RPCTLS_FLAGS_DISABLED;
843 }
844
845 return (ssl);
846 }
847
848 /*
849 * Acquire the dnsname for this server.
850 */
851 static char *
rpctls_getdnsname(char * hostname)852 rpctls_getdnsname(char *hostname)
853 {
854 char *cp, *dnsname;
855 struct addrinfo *aip, hints;
856 int error;
857
858 dnsname = NULL;
859 if (gethostname(hostname, MAXHOSTNAMELEN) == 0) {
860 if ((cp = strchr(hostname, '.')) != NULL &&
861 *(cp + 1) != '\0') {
862 *cp = '@';
863 dnsname = cp;
864 } else {
865 memset((void *)&hints, 0, sizeof (hints));
866 hints.ai_flags = AI_CANONNAME;
867 error = getaddrinfo(hostname, NULL, &hints, &aip);
868 if (error == 0) {
869 if (aip->ai_canonname != NULL &&
870 (cp = strchr(aip->ai_canonname, '.')) !=
871 NULL && *(cp + 1) != '\0') {
872 hostname[0] = '@';
873 strlcpy(&hostname[1], cp + 1,
874 MAXHOSTNAMELEN + 1);
875 dnsname = hostname;
876 }
877 freeaddrinfo(aip);
878 }
879 }
880 }
881 return (dnsname);
882 }
883
884 /*
885 * Check for an otherName component of subjectAltName where the OID
886 * matches and the "domain" matches that of this server.
887 * If found, map "user" to a <uid, gidlist> for it.
888 */
889 static int
rpctls_cnname(X509 * cert,uint32_t * uidp,int * ngrps,uint32_t * gidp)890 rpctls_cnname(X509 *cert, uint32_t *uidp, int *ngrps, uint32_t *gidp)
891 {
892 char *cp, usern[1024 + 1];
893 struct passwd *pwd;
894 gid_t gids[NGROUPS];
895 int i, j;
896 GENERAL_NAMES *genlist;
897 GENERAL_NAME *genname;
898 OTHERNAME *val;
899 size_t slen;
900
901 /* First, find the otherName in the subjectAltName. */
902 genlist = X509_get_ext_d2i(cert, NID_subject_alt_name, NULL, NULL);
903 if (genlist == NULL)
904 return (0);
905 cp = NULL;
906 for (i = 0; i < sk_GENERAL_NAME_num(genlist); i++) {
907 genname = sk_GENERAL_NAME_value(genlist, i);
908 if (genname->type != GEN_OTHERNAME)
909 continue;
910 val = genname->d.otherName;
911
912 /* Check to see that it is the correct OID. */
913 slen = i2t_ASN1_OBJECT(usern, sizeof(usern), val->type_id);
914 if (slen != strlen(rpctls_cnuseroid) || memcmp(usern,
915 rpctls_cnuseroid, slen) != 0)
916 continue;
917
918 /* Sanity check the otherName. */
919 if (val->value->type != V_ASN1_UTF8STRING ||
920 val->value->value.utf8string->length < 3 ||
921 (size_t)val->value->value.utf8string->length > sizeof(usern)
922 - 1) {
923 rpctls_verbose_out("rpctls_cnname: invalid cnuser "
924 "type=%d\n", val->value->type);
925 continue;
926 }
927
928 /* Look for a "user" in the otherName */
929 memcpy(usern, val->value->value.utf8string->data,
930 val->value->value.utf8string->length);
931 usern[val->value->value.utf8string->length] = '\0';
932
933 /* Now, look for the @dnsname suffix in the commonName. */
934 cp = strcasestr(usern, rpctls_dnsname);
935 if (cp == NULL)
936 continue;
937 if (*(cp + strlen(rpctls_dnsname)) != '\0') {
938 cp = NULL;
939 continue;
940 }
941 *cp = '\0';
942 break;
943 }
944 if (cp == NULL)
945 return (0);
946
947 /* See if the "user" is in the passwd database. */
948 pwd = getpwnam(usern);
949 if (pwd == NULL)
950 return (0);
951 *uidp = pwd->pw_uid;
952 *ngrps = NGROUPS;
953 if (getgrouplist(pwd->pw_name, pwd->pw_gid, gids, ngrps) < 0)
954 return (0);
955 rpctls_verbose_out("mapped user=%s ngrps=%d uid=%d\n", pwd->pw_name,
956 *ngrps, pwd->pw_uid);
957 for (j = 0; j < *ngrps; j++)
958 gidp[j] = gids[j];
959 return (1);
960 }
961
962 static void
rpctls_huphandler(int sig __unused)963 rpctls_huphandler(int sig __unused)
964 {
965
966 rpctls_gothup = true;
967 }
968