xref: /freebsd/usr.sbin/rpc.tlsservd/rpc.tlsservd.c (revision 3078531de10dcae44b253a35125c949ff4235284)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
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  *
8  * Redistribution and use in source and binary forms, with or without
9  * modification, are permitted provided that the following conditions
10  * are met:
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in the
15  *    documentation and/or other materials provided with the distribution.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27  * SUCH DAMAGE.
28  */
29 
30 /*
31  * Extensively modified from /usr/src/usr.sbin/gssd.c r344402 for
32  * the server side of kernel RPC-over-TLS by Rick Macklem.
33  */
34 
35 #include <sys/cdefs.h>
36 __FBSDID("$FreeBSD$");
37 
38 #include <sys/param.h>
39 #include <sys/types.h>
40 #include <sys/linker.h>
41 #include <sys/module.h>
42 #include <sys/queue.h>
43 #include <sys/stat.h>
44 #include <sys/sysctl.h>
45 #include <sys/syslog.h>
46 #include <sys/time.h>
47 #include <err.h>
48 #include <getopt.h>
49 #include <libutil.h>
50 #include <netdb.h>
51 #include <pwd.h>
52 #include <signal.h>
53 #include <stdarg.h>
54 #include <stdio.h>
55 #include <stdlib.h>
56 #include <stdbool.h>
57 #include <string.h>
58 #include <unistd.h>
59 
60 #include <rpc/rpc.h>
61 #include <rpc/rpc_com.h>
62 #include <rpc/rpcsec_tls.h>
63 
64 #include <openssl/opensslconf.h>
65 #include <openssl/bio.h>
66 #include <openssl/ssl.h>
67 #include <openssl/err.h>
68 #include <openssl/x509v3.h>
69 
70 #include "rpctlssd.h"
71 #include "rpc.tlscommon.h"
72 
73 #ifndef _PATH_RPCTLSSDSOCK
74 #define _PATH_RPCTLSSDSOCK	"/var/run/rpc.tlsservd.sock"
75 #endif
76 #ifndef	_PATH_CERTANDKEY
77 #define	_PATH_CERTANDKEY	"/etc/rpc.tlsservd/"
78 #endif
79 #ifndef	_PATH_RPCTLSSDPID
80 #define	_PATH_RPCTLSSDPID	"/var/run/rpc.tlsservd.pid"
81 #endif
82 #ifndef	_PREFERRED_CIPHERS
83 #define	_PREFERRED_CIPHERS	"AES128-GCM-SHA256"
84 #endif
85 
86 /* Global variables also used by rpc.tlscommon.c. */
87 int			rpctls_debug_level;
88 bool			rpctls_verbose;
89 SSL_CTX			*rpctls_ctx = NULL;
90 const char		*rpctls_verify_cafile = NULL;
91 const char		*rpctls_verify_capath = NULL;
92 char			*rpctls_crlfile = NULL;
93 bool			rpctls_gothup = false;
94 struct ssl_list		rpctls_ssllist;
95 
96 static struct pidfh	*rpctls_pfh = NULL;
97 static bool		rpctls_do_mutual = false;
98 static const char	*rpctls_certdir = _PATH_CERTANDKEY;
99 static bool		rpctls_comparehost = false;
100 static unsigned int	rpctls_wildcard = X509_CHECK_FLAG_NO_WILDCARDS;
101 static uint64_t		rpctls_ssl_refno = 0;
102 static uint64_t		rpctls_ssl_sec = 0;
103 static uint64_t		rpctls_ssl_usec = 0;
104 static bool		rpctls_cnuser = false;
105 static char		*rpctls_dnsname;
106 static const char	*rpctls_cnuseroid = "1.3.6.1.4.1.2238.1.1.1";
107 static const char	*rpctls_ciphers = NULL;
108 static int		rpctls_mintls = TLS1_3_VERSION;
109 
110 static void		rpctlssd_terminate(int);
111 static SSL_CTX		*rpctls_setup_ssl(const char *certdir);
112 static SSL		*rpctls_server(SSL_CTX *ctx, int s,
113 			    uint32_t *flags, uint32_t *uidp,
114 			    int *ngrps, uint32_t *gidp, X509 **certp);
115 static int		rpctls_cnname(X509 *cert, uint32_t *uidp,
116 			    int *ngrps, uint32_t *gidp);
117 static char		*rpctls_getdnsname(char *dnsname);
118 static void		rpctls_huphandler(int sig __unused);
119 
120 extern void		rpctlssd_1(struct svc_req *rqstp, SVCXPRT *transp);
121 
122 static struct option longopts[] = {
123 	{ "allowtls1_2",	no_argument,		NULL,	'2' },
124 	{ "ciphers",		required_argument,	NULL,	'C' },
125 	{ "certdir",		required_argument,	NULL,	'D' },
126 	{ "debuglevel",		no_argument,		NULL,	'd' },
127 	{ "checkhost",		no_argument,		NULL,	'h' },
128 	{ "verifylocs",		required_argument,	NULL,	'l' },
129 	{ "mutualverf",		no_argument,		NULL,	'm' },
130 	{ "domain",		required_argument,	NULL,	'n' },
131 	{ "verifydir",		required_argument,	NULL,	'p' },
132 	{ "crl",		required_argument,	NULL,	'r' },
133 	{ "certuser",		no_argument,		NULL,	'u' },
134 	{ "verbose",		no_argument,		NULL,	'v' },
135 	{ "multiwild",		no_argument,		NULL,	'W' },
136 	{ "singlewild",		no_argument,		NULL,	'w' },
137 	{ NULL,			0,			NULL,	0  }
138 };
139 
140 int
141 main(int argc, char **argv)
142 {
143 	/*
144 	 * We provide an RPC service on a local-domain socket. The
145 	 * kernel rpctls code will upcall to this daemon to do the initial
146 	 * TLS handshake.
147 	 */
148 	struct sockaddr_un sun;
149 	int ch, fd, oldmask;
150 	SVCXPRT *xprt;
151 	struct timeval tm;
152 	struct timezone tz;
153 	char hostname[MAXHOSTNAMELEN + 2];
154 	pid_t otherpid;
155 	bool tls_enable;
156 	size_t tls_enable_len;
157 
158 	/* Check that another rpctlssd isn't already running. */
159 	rpctls_pfh = pidfile_open(_PATH_RPCTLSSDPID, 0600, &otherpid);
160 	if (rpctls_pfh == NULL) {
161 		if (errno == EEXIST)
162 			errx(1, "rpctlssd already running, pid: %d.", otherpid);
163 		warn("cannot open or create pidfile");
164 	}
165 
166 	/* Check to see that the ktls is enabled. */
167 	tls_enable_len = sizeof(tls_enable);
168 	if (sysctlbyname("kern.ipc.tls.enable", &tls_enable, &tls_enable_len,
169 	    NULL, 0) != 0 || !tls_enable)
170 		errx(1, "Kernel TLS not enabled");
171 
172 	/* Get the time when this daemon is started. */
173 	gettimeofday(&tm, &tz);
174 	rpctls_ssl_sec = tm.tv_sec;
175 	rpctls_ssl_usec = tm.tv_usec;
176 
177 	/* Set the dns name for the server. */
178 	rpctls_dnsname = rpctls_getdnsname(hostname);
179 	if (rpctls_dnsname == NULL) {
180 		strcpy(hostname, "@default.domain");
181 		rpctls_dnsname = hostname;
182 	}
183 
184 	rpctls_verbose = false;
185 	while ((ch = getopt_long(argc, argv, "2C:D:dhl:n:mp:r:uvWw", longopts,
186 	    NULL)) != -1) {
187 		switch (ch) {
188 		case '2':
189 			rpctls_mintls = TLS1_2_VERSION;
190 			break;
191 		case 'C':
192 			rpctls_ciphers = optarg;
193 			break;
194 		case 'D':
195 			rpctls_certdir = optarg;
196 			break;
197 		case 'd':
198 			rpctls_debug_level++;
199 			break;
200 		case 'h':
201 			rpctls_comparehost = true;
202 			break;
203 		case 'l':
204 			rpctls_verify_cafile = optarg;
205 			break;
206 		case 'm':
207 			rpctls_do_mutual = true;
208 			break;
209 		case 'n':
210 			hostname[0] = '@';
211 			strlcpy(&hostname[1], optarg, MAXHOSTNAMELEN + 1);
212 			rpctls_dnsname = hostname;
213 			break;
214 		case 'p':
215 			rpctls_verify_capath = optarg;
216 			break;
217 		case 'r':
218 			rpctls_crlfile = optarg;
219 			break;
220 		case 'u':
221 			rpctls_cnuser = true;
222 			break;
223 		case 'v':
224 			rpctls_verbose = true;
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 = X509_CHECK_FLAG_MULTI_LABEL_WILDCARDS;
231 			break;
232 		case 'w':
233 			if (rpctls_wildcard != X509_CHECK_FLAG_NO_WILDCARDS)
234 				errx(1, "options -w and -W are mutually "
235 				    "exclusive");
236 			rpctls_wildcard = 0;
237 			break;
238 		default:
239 			fprintf(stderr, "usage: %s "
240 			    "[-2/--allowtls1_2] "
241 			    "[-C/--ciphers available_ciphers] "
242 			    "[-D/--certdir certdir] [-d/--debuglevel] "
243 			    "[-h/--checkhost] "
244 			    "[-l/--verifylocs CAfile] [-m/--mutualverf] "
245 			    "[-n/--domain domain_name] "
246 			    "[-p/--verifydir CApath] [-r/--crl CRLfile] "
247 			    "[-u/--certuser] [-v/--verbose] [-W/--multiwild] "
248 			    "[-w/--singlewild]\n", argv[0]);
249 			exit(1);
250 		}
251 	}
252 	if (rpctls_do_mutual && rpctls_verify_cafile == NULL &&
253 	    rpctls_verify_capath == NULL)
254 		errx(1, "-m requires the -l <CAfile> and/or "
255 		    "-p <CApath> options");
256 	if (rpctls_comparehost && (!rpctls_do_mutual ||
257 	    (rpctls_verify_cafile == NULL && rpctls_verify_capath == NULL)))
258 		errx(1, "-h requires the -m plus the "
259 		    "-l <CAfile> and/or -p <CApath> options");
260 	if (!rpctls_comparehost && rpctls_wildcard !=
261 	    X509_CHECK_FLAG_NO_WILDCARDS)
262 		errx(1, "The -w or -W options require the -h option");
263 	if (rpctls_cnuser && (!rpctls_do_mutual ||
264 	    (rpctls_verify_cafile == NULL && rpctls_verify_capath == NULL)))
265 		errx(1, "-u requires the -m plus the "
266 		    "-l <CAfile> and/or -p <CApath> options");
267 
268 	if (modfind("krpc") < 0) {
269 		/* Not present in kernel, try loading it */
270 		if (kldload("krpc") < 0 || modfind("krpc") < 0)
271 			errx(1, "Kernel RPC is not available");
272 	}
273 
274 	if (rpctls_debug_level == 0) {
275 		if (daemon(0, 0) != 0)
276 			err(1, "Can't daemonize");
277 		signal(SIGINT, SIG_IGN);
278 		signal(SIGQUIT, SIG_IGN);
279 		signal(SIGHUP, SIG_IGN);
280 	}
281 	signal(SIGTERM, rpctlssd_terminate);
282 	signal(SIGPIPE, SIG_IGN);
283 	signal(SIGHUP, rpctls_huphandler);
284 
285 	pidfile_write(rpctls_pfh);
286 
287 	memset(&sun, 0, sizeof sun);
288 	sun.sun_family = AF_LOCAL;
289 	unlink(_PATH_RPCTLSSDSOCK);
290 	strcpy(sun.sun_path, _PATH_RPCTLSSDSOCK);
291 	sun.sun_len = SUN_LEN(&sun);
292 	fd = socket(AF_LOCAL, SOCK_STREAM, 0);
293 	if (fd < 0) {
294 		if (rpctls_debug_level == 0) {
295 			syslog(LOG_ERR, "Can't create local rpctlssd socket");
296 			exit(1);
297 		}
298 		err(1, "Can't create local rpctlssd socket");
299 	}
300 	oldmask = umask(S_IXUSR|S_IRWXG|S_IRWXO);
301 	if (bind(fd, (struct sockaddr *)&sun, sun.sun_len) < 0) {
302 		if (rpctls_debug_level == 0) {
303 			syslog(LOG_ERR, "Can't bind local rpctlssd socket");
304 			exit(1);
305 		}
306 		err(1, "Can't bind local rpctlssd socket");
307 	}
308 	umask(oldmask);
309 	if (listen(fd, SOMAXCONN) < 0) {
310 		if (rpctls_debug_level == 0) {
311 			syslog(LOG_ERR,
312 			    "Can't listen on local rpctlssd socket");
313 			exit(1);
314 		}
315 		err(1, "Can't listen on local rpctlssd socket");
316 	}
317 	xprt = svc_vc_create(fd, RPC_MAXDATASIZE, RPC_MAXDATASIZE);
318 	if (!xprt) {
319 		if (rpctls_debug_level == 0) {
320 			syslog(LOG_ERR,
321 			    "Can't create transport for local rpctlssd socket");
322 			exit(1);
323 		}
324 		err(1, "Can't create transport for local rpctlssd socket");
325 	}
326 	if (!svc_reg(xprt, RPCTLSSD, RPCTLSSDVERS, rpctlssd_1, NULL)) {
327 		if (rpctls_debug_level == 0) {
328 			syslog(LOG_ERR,
329 			    "Can't register service for local rpctlssd socket");
330 			exit(1);
331 		}
332 		err(1, "Can't register service for local rpctlssd socket");
333 	}
334 
335 	rpctls_ctx = rpctls_setup_ssl(rpctls_certdir);
336 	if (rpctls_ctx == NULL) {
337 		if (rpctls_debug_level == 0) {
338 			syslog(LOG_ERR, "Can't create SSL context");
339 			exit(1);
340 		}
341 		err(1, "Can't create SSL context");
342 	}
343 	rpctls_gothup = false;
344 	LIST_INIT(&rpctls_ssllist);
345 
346 	rpctls_syscall(RPCTLS_SYSC_SRVSETPATH, _PATH_RPCTLSSDSOCK);
347 
348 	rpctls_svc_run();
349 
350 	rpctls_syscall(RPCTLS_SYSC_SRVSHUTDOWN, "");
351 
352 	SSL_CTX_free(rpctls_ctx);
353 	EVP_cleanup();
354 	return (0);
355 }
356 
357 bool_t
358 rpctlssd_null_1_svc(__unused void *argp, __unused void *result,
359     __unused struct svc_req *rqstp)
360 {
361 
362 	rpctls_verbose_out("rpctlssd_null_svc: done\n");
363 	return (TRUE);
364 }
365 
366 bool_t
367 rpctlssd_connect_1_svc(__unused void *argp,
368     struct rpctlssd_connect_res *result, __unused struct svc_req *rqstp)
369 {
370 	int ngrps, s;
371 	SSL *ssl;
372 	uint32_t flags;
373 	struct ssl_entry *newslp;
374 	uint32_t uid;
375 	uint32_t *gidp;
376 	X509 *cert;
377 
378 	rpctls_verbose_out("rpctlsd_connect_svc: started\n");
379 	memset(result, 0, sizeof(*result));
380 	/* Get the socket fd from the kernel. */
381 	s = rpctls_syscall(RPCTLS_SYSC_SRVSOCKET, "");
382 	if (s < 0)
383 		return (FALSE);
384 
385 	/* Do the server side of a TLS handshake. */
386 	gidp = calloc(NGROUPS, sizeof(*gidp));
387 	ssl = rpctls_server(rpctls_ctx, s, &flags, &uid, &ngrps, gidp, &cert);
388 	if (ssl == NULL) {
389 		free(gidp);
390 		rpctls_verbose_out("rpctlssd_connect_svc: ssl "
391 		    "accept failed\n");
392 		/*
393 		 * For RPC-over-TLS, this upcall is expected
394 		 * to close off the socket upon handshake failure.
395 		 */
396 		close(s);
397 		return (FALSE);
398 	} else {
399 		rpctls_verbose_out("rpctlssd_connect_svc: "
400 		    "succeeded flags=0x%x\n", flags);
401 		result->flags = flags;
402 		result->sec = rpctls_ssl_sec;
403 		result->usec = rpctls_ssl_usec;
404 		result->ssl = ++rpctls_ssl_refno;
405 		/* Hard to believe this could ever wrap around.. */
406 		if (rpctls_ssl_refno == 0)
407 			result->ssl = ++rpctls_ssl_refno;
408 		if ((flags & RPCTLS_FLAGS_CERTUSER) != 0) {
409 			result->uid = uid;
410 			result->gid.gid_len = ngrps;
411 			result->gid.gid_val = gidp;
412 		} else {
413 			result->uid = 0;
414 			result->gid.gid_len = 0;
415 			result->gid.gid_val = gidp;
416 		}
417 	}
418 
419 	/* Maintain list of all current SSL *'s */
420 	newslp = malloc(sizeof(*newslp));
421 	newslp->ssl = ssl;
422 	newslp->s = s;
423 	newslp->shutoff = false;
424 	newslp->refno = rpctls_ssl_refno;
425 	newslp->cert = cert;
426 	LIST_INSERT_HEAD(&rpctls_ssllist, newslp, next);
427 	return (TRUE);
428 }
429 
430 bool_t
431 rpctlssd_handlerecord_1_svc(struct rpctlssd_handlerecord_arg *argp,
432     struct rpctlssd_handlerecord_res *result, __unused struct svc_req *rqstp)
433 {
434 	struct ssl_entry *slp;
435 	int ret;
436 	char junk;
437 
438 	slp = NULL;
439 	if (argp->sec == rpctls_ssl_sec && argp->usec ==
440 	    rpctls_ssl_usec) {
441 		LIST_FOREACH(slp, &rpctls_ssllist, next) {
442 			if (slp->refno == argp->ssl)
443 				break;
444 		}
445 	}
446 
447 	if (slp != NULL) {
448 		rpctls_verbose_out("rpctlssd_handlerecord fd=%d\n",
449 		    slp->s);
450 		/*
451 		 * An SSL_read() of 0 bytes should fail, but it should
452 		 * handle the non-application data record before doing so.
453 		 */
454 		ret = SSL_read(slp->ssl, &junk, 0);
455 		if (ret <= 0) {
456 			/* Check to see if this was a close alert. */
457 			ret = SSL_get_shutdown(slp->ssl);
458 			if ((ret & (SSL_SENT_SHUTDOWN |
459 			    SSL_RECEIVED_SHUTDOWN)) == SSL_RECEIVED_SHUTDOWN)
460 				SSL_shutdown(slp->ssl);
461 		} else {
462 			if (rpctls_debug_level == 0)
463 				syslog(LOG_ERR, "SSL_read returned %d", ret);
464 			else
465 				fprintf(stderr, "SSL_read returned %d\n", ret);
466 		}
467 		result->reterr = RPCTLSERR_OK;
468 	} else
469 		result->reterr = RPCTLSERR_NOSSL;
470 	return (TRUE);
471 }
472 
473 bool_t
474 rpctlssd_disconnect_1_svc(struct rpctlssd_disconnect_arg *argp,
475     struct rpctlssd_disconnect_res *result, __unused struct svc_req *rqstp)
476 {
477 	struct ssl_entry *slp;
478 	int ret;
479 
480 	slp = NULL;
481 	if (argp->sec == rpctls_ssl_sec && argp->usec ==
482 	    rpctls_ssl_usec) {
483 		LIST_FOREACH(slp, &rpctls_ssllist, next) {
484 			if (slp->refno == argp->ssl)
485 				break;
486 		}
487 	}
488 
489 	if (slp != NULL) {
490 		rpctls_verbose_out("rpctlssd_disconnect fd=%d closed\n",
491 		    slp->s);
492 		LIST_REMOVE(slp, next);
493 		if (!slp->shutoff) {
494 			ret = SSL_get_shutdown(slp->ssl);
495 			/*
496 			 * Do an SSL_shutdown() unless a close alert has
497 			 * already been sent.
498 			 */
499 			if ((ret & SSL_SENT_SHUTDOWN) == 0)
500 				SSL_shutdown(slp->ssl);
501 		}
502 		SSL_free(slp->ssl);
503 		if (slp->cert != NULL)
504 			X509_free(slp->cert);
505 		/*
506 		 * For RPC-over-TLS, this upcall is expected
507 		 * to close off the socket.
508 		 */
509 		if (!slp->shutoff)
510 			shutdown(slp->s, SHUT_WR);
511 		close(slp->s);
512 		free(slp);
513 		result->reterr = RPCTLSERR_OK;
514 	} else
515 		result->reterr = RPCTLSERR_NOCLOSE;
516 	return (TRUE);
517 }
518 
519 int
520 rpctlssd_1_freeresult(__unused SVCXPRT *transp, xdrproc_t xdr_result,
521     caddr_t result)
522 {
523 	rpctlssd_connect_res *res;
524 
525 	if (xdr_result == (xdrproc_t)xdr_rpctlssd_connect_res) {
526 		res = (rpctlssd_connect_res *)(void *)result;
527 		free(res->gid.gid_val);
528 	}
529 	return (TRUE);
530 }
531 
532 static void
533 rpctlssd_terminate(int sig __unused)
534 {
535 	struct ssl_entry *slp;
536 
537 	rpctls_syscall(RPCTLS_SYSC_SRVSHUTDOWN, "");
538 	pidfile_remove(rpctls_pfh);
539 
540 	LIST_FOREACH(slp, &rpctls_ssllist, next)
541 		shutdown(slp->s, SHUT_RD);
542 	exit(0);
543 }
544 
545 /* Allow the handshake to proceed. */
546 static int
547 rpctls_verify_callback(__unused int preverify_ok,
548     __unused X509_STORE_CTX *x509_ctx)
549 {
550 
551 	return (1);
552 }
553 
554 static SSL_CTX *
555 rpctls_setup_ssl(const char *certdir)
556 {
557 	SSL_CTX *ctx;
558 	char path[PATH_MAX];
559 	size_t len, rlen;
560 	int ret;
561 
562 	SSL_library_init();
563 	SSL_load_error_strings();
564 	OpenSSL_add_all_algorithms();
565 
566 	ctx = SSL_CTX_new(TLS_server_method());
567 	if (ctx == NULL) {
568 		rpctls_verbose_out("rpctls_setup_ssl: SSL_CTX_new failed\n");
569 		return (NULL);
570 	}
571 	SSL_CTX_set_ecdh_auto(ctx, 1);
572 
573 	if (rpctls_ciphers != NULL) {
574 		/*
575 		 * Set available ciphers, since KERN_TLS only supports a
576 		 * few of them.  Normally, not doing this should be ok,
577 		 * since the library defaults will work.
578 		 */
579 		ret = SSL_CTX_set_ciphersuites(ctx, rpctls_ciphers);
580 		if (ret == 0) {
581 			rpctls_verbose_out("rpctls_setup_ssl: "
582 			    "SSL_CTX_set_ciphersuites failed: %s\n",
583 			    rpctls_ciphers);
584 			SSL_CTX_free(ctx);
585 			return (NULL);
586 		}
587 	}
588 
589 	ret = SSL_CTX_set_min_proto_version(ctx, rpctls_mintls);
590 	if (ret == 0) {
591 		rpctls_verbose_out("rpctls_setup_ssl: "
592 		    "SSL_CTX_set_min_proto_version failed\n");
593 		SSL_CTX_free(ctx);
594 		return (NULL);
595 	}
596 	ret = SSL_CTX_set_max_proto_version(ctx, TLS1_3_VERSION);
597 	if (ret == 0) {
598 		rpctls_verbose_out("rpctls_setup_ssl: "
599 		    "SSL_CTX_set_max_proto_version failed\n");
600 		SSL_CTX_free(ctx);
601 		return (NULL);
602 	}
603 
604 	/* Get the cert.pem and certkey.pem files from the directory certdir. */
605 	len = strlcpy(path, certdir, sizeof(path));
606 	rlen = sizeof(path) - len;
607 	if (strlcpy(&path[len], "cert.pem", rlen) != 8) {
608 		SSL_CTX_free(ctx);
609 		return (NULL);
610 	}
611 	ret = SSL_CTX_use_certificate_file(ctx, path, SSL_FILETYPE_PEM);
612 	if (ret != 1) {
613 		rpctls_verbose_out("rpctls_setup_ssl: can't use certificate "
614 		    "file path=%s ret=%d\n", path, ret);
615 		SSL_CTX_free(ctx);
616 		return (NULL);
617 	}
618 	if (strlcpy(&path[len], "certkey.pem", rlen) != 11) {
619 		SSL_CTX_free(ctx);
620 		return (NULL);
621 	}
622 	ret = SSL_CTX_use_PrivateKey_file(ctx, path, SSL_FILETYPE_PEM);
623 	if (ret != 1) {
624 		rpctls_verbose_out("rpctls_setup_ssl: Can't use private "
625 		    "key path=%s ret=%d\n", path, ret);
626 		SSL_CTX_free(ctx);
627 		return (NULL);
628 	}
629 
630 	/* Set Mutual authentication, as required. */
631 	if (rpctls_do_mutual) {
632 		if (rpctls_verify_cafile != NULL ||
633 		    rpctls_verify_capath != NULL) {
634 			if (rpctls_crlfile != NULL) {
635 				ret = rpctls_loadcrlfile(ctx);
636 				if (ret == 0) {
637 					rpctls_verbose_out("rpctls_setup_ssl:"
638 					    " Load CRLfile failed\n");
639 					SSL_CTX_free(ctx);
640 					return (NULL);
641 				}
642 			}
643 #if OPENSSL_VERSION_NUMBER >= 0x30000000
644 			ret = 1;
645 			if (rpctls_verify_cafile != NULL)
646 				ret = SSL_CTX_load_verify_file(ctx,
647 				    rpctls_verify_cafile);
648 			if (ret != 0 && rpctls_verify_capath != NULL)
649 				ret = SSL_CTX_load_verify_dir(ctx,
650 				    rpctls_verify_capath);
651 #else
652 			ret = SSL_CTX_load_verify_locations(ctx,
653 			    rpctls_verify_cafile, rpctls_verify_capath);
654 #endif
655 			if (ret == 0) {
656 				rpctls_verbose_out("rpctls_setup_ssl: "
657 				    "Can't load verify locations\n");
658 				SSL_CTX_free(ctx);
659 				return (NULL);
660 			}
661 			if (rpctls_verify_cafile != NULL)
662 				SSL_CTX_set_client_CA_list(ctx,
663 				    SSL_load_client_CA_file(
664 			    rpctls_verify_cafile));
665 		}
666 		SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER,
667 		    rpctls_verify_callback);
668 	}
669 #ifdef SSL_OP_ENABLE_KTLS
670 	SSL_CTX_set_options(ctx, SSL_OP_ENABLE_KTLS);
671 #endif
672 #ifdef SSL_MODE_NO_KTLS_TX
673 	SSL_CTX_clear_mode(ctx, SSL_MODE_NO_KTLS_TX | SSL_MODE_NO_KTLS_RX);
674 #endif
675 	return (ctx);
676 }
677 
678 static SSL *
679 rpctls_server(SSL_CTX *ctx, int s, uint32_t *flags, uint32_t *uidp,
680     int *ngrps, uint32_t *gidp, X509 **certp)
681 {
682 	SSL *ssl;
683 	X509 *cert;
684 	struct sockaddr *sad;
685 	struct sockaddr_storage ad;
686 	char hostnam[NI_MAXHOST];
687 	int gethostret, ret;
688 	char *cp, *cp2;
689 	long verfret;
690 
691 	*flags = 0;
692 	*certp = NULL;
693 	sad = (struct sockaddr *)&ad;
694 	ssl = SSL_new(ctx);
695 	if (ssl == NULL) {
696 		rpctls_verbose_out("rpctls_server: SSL_new failed\n");
697 		return (NULL);
698 	}
699 	if (SSL_set_fd(ssl, s) != 1) {
700 		rpctls_verbose_out("rpctls_server: SSL_set_fd failed\n");
701 		SSL_free(ssl);
702 		return (NULL);
703 	}
704 	ret = SSL_accept(ssl);
705 	if (ret != 1) {
706 		rpctls_verbose_out("rpctls_server: SSL_accept "
707 		    "failed ret=%d\n", ret);
708 		SSL_free(ssl);
709 		return (NULL);
710 	}
711 	*flags |= RPCTLS_FLAGS_HANDSHAKE;
712 	if (rpctls_verbose) {
713 		gethostret = rpctls_gethost(s, sad, hostnam, sizeof(hostnam));
714 		if (gethostret == 0)
715 			hostnam[0] = '\0';
716 		rpctls_verbose_out("rpctls_server: SSL handshake ok for host %s"
717 		    " <%s %s>\n", hostnam, SSL_get_version(ssl),
718 		    SSL_get_cipher(ssl));
719 	}
720 	if (rpctls_do_mutual) {
721 		cert = SSL_get_peer_certificate(ssl);
722 		if (cert != NULL) {
723 			if (!rpctls_verbose) {
724 				gethostret = rpctls_gethost(s, sad, hostnam,
725 				    sizeof(hostnam));
726 				if (gethostret == 0)
727 					hostnam[0] = '\0';
728 			}
729 			cp2 = X509_NAME_oneline(
730 			    X509_get_subject_name(cert), NULL, 0);
731 			*flags |= RPCTLS_FLAGS_GOTCERT;
732 			verfret = SSL_get_verify_result(ssl);
733 			if (verfret != X509_V_OK) {
734 				cp = X509_NAME_oneline(
735 				    X509_get_issuer_name(cert), NULL, 0);
736 				if (rpctls_debug_level == 0)
737 					syslog(LOG_INFO | LOG_DAEMON,
738 					    "rpctls_server: client IP %s "
739 					    "issuerName=%s subjectName=%s"
740 					    " verify failed %s\n", hostnam,
741 					    cp, cp2,
742 					    X509_verify_cert_error_string(
743 					    verfret));
744 				else
745 					fprintf(stderr,
746 					    "rpctls_server: client IP %s "
747 					    "issuerName=%s subjectName=%s"
748 					    " verify failed %s\n", hostnam,
749 					    cp, cp2,
750 					    X509_verify_cert_error_string(
751 					    verfret));
752 			}
753 			if (verfret ==
754 			    X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT ||
755 			    verfret == X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN)
756 				*flags |= RPCTLS_FLAGS_SELFSIGNED;
757 			else if (verfret == X509_V_OK) {
758 				if (rpctls_comparehost) {
759 					ret = 0;
760 					if (gethostret != 0)
761 						ret = rpctls_checkhost(sad,
762 						    cert, rpctls_wildcard);
763 					if (ret != 1) {
764 						*flags |=
765 						    RPCTLS_FLAGS_DISABLED;
766 						rpctls_verbose_out(
767 						    "rpctls_server: "
768 						    "checkhost "
769 						    "failed\n");
770 					}
771 				}
772 				if (rpctls_cnuser) {
773 					ret = rpctls_cnname(cert, uidp,
774 					    ngrps, gidp);
775 					if (ret != 0)
776 						*flags |= RPCTLS_FLAGS_CERTUSER;
777 				}
778 				*flags |= RPCTLS_FLAGS_VERIFIED;
779 				*certp = cert;
780 				cert = NULL;
781 			}
782 			if (cert != NULL)
783 				X509_free(cert);
784 		} else
785 			rpctls_verbose_out("rpctls_server: "
786 			    "No peer certificate\n");
787 	}
788 
789 	/* Check to see that ktls is working for the connection. */
790 	ret = BIO_get_ktls_send(SSL_get_wbio(ssl));
791 	rpctls_verbose_out("rpctls_server: BIO_get_ktls_send=%d\n", ret);
792 	if (ret != 0) {
793 		ret = BIO_get_ktls_recv(SSL_get_rbio(ssl));
794 		rpctls_verbose_out("rpctls_server: BIO_get_ktls_recv=%d\n",
795 		    ret);
796 	}
797 	if (ret == 0) {
798 		if (rpctls_debug_level == 0)
799 			syslog(LOG_ERR, "ktls not working");
800 		else
801 			fprintf(stderr, "ktls not working\n");
802 		/*
803 		 * The handshake has completed, so all that can be
804 		 * done is disable the connection.
805 		 */
806 		*flags |= RPCTLS_FLAGS_DISABLED;
807 	}
808 
809 	return (ssl);
810 }
811 
812 /*
813  * Acquire the dnsname for this server.
814  */
815 static char *
816 rpctls_getdnsname(char *hostname)
817 {
818 	char *cp, *dnsname;
819 	struct addrinfo *aip, hints;
820 	int error;
821 
822 	dnsname = NULL;
823 	if (gethostname(hostname, MAXHOSTNAMELEN) == 0) {
824 		if ((cp = strchr(hostname, '.')) != NULL &&
825 		    *(cp + 1) != '\0') {
826 			*cp = '@';
827 			dnsname = cp;
828 		} else {
829 			memset((void *)&hints, 0, sizeof (hints));
830 			hints.ai_flags = AI_CANONNAME;
831 			error = getaddrinfo(hostname, NULL, &hints, &aip);
832 			if (error == 0) {
833 				if (aip->ai_canonname != NULL &&
834 				    (cp = strchr(aip->ai_canonname, '.')) !=
835 				    NULL && *(cp + 1) != '\0') {
836 					hostname[0] = '@';
837 					strlcpy(&hostname[1], cp + 1,
838 					    MAXHOSTNAMELEN + 1);
839 					dnsname = hostname;
840 				}
841 				freeaddrinfo(aip);
842 			}
843 		}
844 	}
845 	return (dnsname);
846 }
847 
848 /*
849  * Check for an otherName component of subjectAltName where the OID
850  * matches and the "domain" matches that of this server.
851  * If found, map "user" to a <uid, gidlist> for it.
852  */
853 static int
854 rpctls_cnname(X509 *cert, uint32_t *uidp, int *ngrps, uint32_t *gidp)
855 {
856 	char *cp, usern[1024 + 1];
857 	struct passwd *pwd;
858 	gid_t gids[NGROUPS];
859 	int i, j;
860 	GENERAL_NAMES *genlist;
861 	GENERAL_NAME *genname;
862 	OTHERNAME *val;
863 	size_t slen;
864 
865 	/* First, find the otherName in the subjectAltName. */
866 	genlist = X509_get_ext_d2i(cert, NID_subject_alt_name, NULL, NULL);
867 	if (genlist == NULL)
868 		return (0);
869 	cp = NULL;
870 	for (i = 0; i < sk_GENERAL_NAME_num(genlist); i++) {
871 		genname = sk_GENERAL_NAME_value(genlist, i);
872 		if (genname->type != GEN_OTHERNAME)
873 			continue;
874 		val = genname->d.otherName;
875 
876 		/* Check to see that it is the correct OID. */
877 		slen = i2t_ASN1_OBJECT(usern, sizeof(usern), val->type_id);
878 		if (slen != strlen(rpctls_cnuseroid) || memcmp(usern,
879 		    rpctls_cnuseroid, slen) != 0)
880 			continue;
881 
882 		/* Sanity check the otherName. */
883 		if (val->value->type != V_ASN1_UTF8STRING ||
884 		    val->value->value.utf8string->length < 3 ||
885 		    (size_t)val->value->value.utf8string->length > sizeof(usern)
886 		    - 1) {
887 			rpctls_verbose_out("rpctls_cnname: invalid cnuser "
888 			    "type=%d\n", val->value->type);
889 			continue;
890 		}
891 
892 		/* Look for a "user" in the otherName */
893 		memcpy(usern, val->value->value.utf8string->data,
894 		    val->value->value.utf8string->length);
895 		usern[val->value->value.utf8string->length] = '\0';
896 
897 		/* Now, look for the @dnsname suffix in the commonName. */
898 		cp = strcasestr(usern, rpctls_dnsname);
899 		if (cp == NULL)
900 			continue;
901 		if (*(cp + strlen(rpctls_dnsname)) != '\0') {
902 			cp = NULL;
903 			continue;
904 		}
905 		*cp = '\0';
906 		break;
907 	}
908 	if (cp == NULL)
909 		return (0);
910 
911 	/* See if the "user" is in the passwd database. */
912 	pwd = getpwnam(usern);
913 	if (pwd == NULL)
914 		return (0);
915 	*uidp = pwd->pw_uid;
916 	*ngrps = NGROUPS;
917 	if (getgrouplist(pwd->pw_name, pwd->pw_gid, gids, ngrps) < 0)
918 		return (0);
919 	rpctls_verbose_out("mapped user=%s ngrps=%d uid=%d\n", pwd->pw_name,
920 	    *ngrps, pwd->pw_uid);
921 	for (j = 0; j < *ngrps; j++)
922 		gidp[j] = gids[j];
923 	return (1);
924 }
925 
926 static void
927 rpctls_huphandler(int sig __unused)
928 {
929 
930 	rpctls_gothup = true;
931 }
932