xref: /freebsd/usr.sbin/rpc.tlsservd/rpc.tlsservd.c (revision dd41de95a84d979615a2ef11df6850622bf6184e)
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 
108 static void		rpctlssd_terminate(int);
109 static SSL_CTX		*rpctls_setup_ssl(const char *certdir);
110 static SSL		*rpctls_server(SSL_CTX *ctx, int s,
111 			    uint32_t *flags, uint32_t *uidp,
112 			    int *ngrps, uint32_t *gidp, X509 **certp);
113 static int		rpctls_cnname(X509 *cert, uint32_t *uidp,
114 			    int *ngrps, uint32_t *gidp);
115 static char		*rpctls_getdnsname(char *dnsname);
116 static void		rpctls_huphandler(int sig __unused);
117 
118 extern void		rpctlssd_1(struct svc_req *rqstp, SVCXPRT *transp);
119 
120 static struct option longopts[] = {
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 	{ "domain",		required_argument,	NULL,	'n' },
127 	{ "verifydir",		required_argument,	NULL,	'p' },
128 	{ "crl",		required_argument,	NULL,	'r' },
129 	{ "certuser",		no_argument,		NULL,	'u' },
130 	{ "verbose",		no_argument,		NULL,	'v' },
131 	{ "multiwild",		no_argument,		NULL,	'W' },
132 	{ "singlewild",		no_argument,		NULL,	'w' },
133 	{ NULL,			0,			NULL,	0  }
134 };
135 
136 int
137 main(int argc, char **argv)
138 {
139 	/*
140 	 * We provide an RPC service on a local-domain socket. The
141 	 * kernel rpctls code will upcall to this daemon to do the initial
142 	 * TLS handshake.
143 	 */
144 	struct sockaddr_un sun;
145 	int ch, debug, fd, oldmask;
146 	SVCXPRT *xprt;
147 	struct timeval tm;
148 	struct timezone tz;
149 	char hostname[MAXHOSTNAMELEN + 2];
150 	pid_t otherpid;
151 	bool tls_enable;
152 	size_t tls_enable_len;
153 
154 	/* Check that another rpctlssd isn't already running. */
155 	rpctls_pfh = pidfile_open(_PATH_RPCTLSSDPID, 0600, &otherpid);
156 	if (rpctls_pfh == NULL) {
157 		if (errno == EEXIST)
158 			errx(1, "rpctlssd already running, pid: %d.", otherpid);
159 		warn("cannot open or create pidfile");
160 	}
161 
162 	/* Check to see that the ktls is enabled. */
163 	tls_enable_len = sizeof(tls_enable);
164 	if (sysctlbyname("kern.ipc.tls.enable", &tls_enable, &tls_enable_len,
165 	    NULL, 0) != 0 || !tls_enable)
166 		errx(1, "Kernel TLS not enabled");
167 
168 	/* Get the time when this daemon is started. */
169 	gettimeofday(&tm, &tz);
170 	rpctls_ssl_sec = tm.tv_sec;
171 	rpctls_ssl_usec = tm.tv_usec;
172 
173 	/* Set the dns name for the server. */
174 	rpctls_dnsname = rpctls_getdnsname(hostname);
175 	if (rpctls_dnsname == NULL) {
176 		strcpy(hostname, "@default.domain");
177 		rpctls_dnsname = hostname;
178 	}
179 
180 	debug = 0;
181 	rpctls_verbose = false;
182 	while ((ch = getopt_long(argc, argv, "D:dhl:n:mp:r:uvWw", longopts,
183 	    NULL)) != -1) {
184 		switch (ch) {
185 		case 'D':
186 			rpctls_certdir = optarg;
187 			break;
188 		case 'd':
189 			rpctls_debug_level++;
190 			break;
191 		case 'h':
192 			rpctls_comparehost = true;
193 			break;
194 		case 'l':
195 			rpctls_verify_cafile = optarg;
196 			break;
197 		case 'm':
198 			rpctls_do_mutual = true;
199 			break;
200 		case 'n':
201 			hostname[0] = '@';
202 			strlcpy(&hostname[1], optarg, MAXHOSTNAMELEN + 1);
203 			rpctls_dnsname = hostname;
204 			break;
205 		case 'p':
206 			rpctls_verify_capath = optarg;
207 			break;
208 		case 'r':
209 			rpctls_crlfile = optarg;
210 			break;
211 		case 'u':
212 			rpctls_cnuser = true;
213 			break;
214 		case 'v':
215 			rpctls_verbose = true;
216 			break;
217 		case 'W':
218 			if (rpctls_wildcard != X509_CHECK_FLAG_NO_WILDCARDS)
219 				errx(1, "options -w and -W are mutually "
220 				    "exclusive");
221 			rpctls_wildcard = X509_CHECK_FLAG_MULTI_LABEL_WILDCARDS;
222 			break;
223 		case 'w':
224 			if (rpctls_wildcard != X509_CHECK_FLAG_NO_WILDCARDS)
225 				errx(1, "options -w and -W are mutually "
226 				    "exclusive");
227 			rpctls_wildcard = 0;
228 			break;
229 		default:
230 			fprintf(stderr, "usage: %s "
231 			    "[-D/--certdir certdir] [-d/--debuglevel] "
232 			    "[-h/--checkhost] "
233 			    "[-l/--verifylocs CAfile] [-m/--mutualverf] "
234 			    "[-n/--domain domain_name] "
235 			    "[-p/--verifydir CApath] [-r/--crl CRLfile] "
236 			    "[-u/--certuser] [-v/--verbose] [-W/--multiwild] "
237 			    "[-w/--singlewild]\n", argv[0]);
238 			exit(1);
239 		}
240 	}
241 	if (rpctls_do_mutual && rpctls_verify_cafile == NULL &&
242 	    rpctls_verify_capath == NULL)
243 		errx(1, "-m requires the -l <CAfile> and/or "
244 		    "-p <CApath> options");
245 	if (rpctls_comparehost && (!rpctls_do_mutual ||
246 	    (rpctls_verify_cafile == NULL && rpctls_verify_capath == NULL)))
247 		errx(1, "-h requires the -m plus the "
248 		    "-l <CAfile> and/or -p <CApath> options");
249 	if (!rpctls_comparehost && rpctls_wildcard !=
250 	    X509_CHECK_FLAG_NO_WILDCARDS)
251 		errx(1, "The -w or -W options require the -h option");
252 	if (rpctls_cnuser && (!rpctls_do_mutual ||
253 	    (rpctls_verify_cafile == NULL && rpctls_verify_capath == NULL)))
254 		errx(1, "-u requires the -m plus the "
255 		    "-l <CAfile> and/or -p <CApath> options");
256 
257 	if (modfind("krpc") < 0) {
258 		/* Not present in kernel, try loading it */
259 		if (kldload("krpc") < 0 || modfind("krpc") < 0)
260 			errx(1, "Kernel RPC is not available");
261 	}
262 
263 	if (rpctls_debug_level == 0) {
264 		if (daemon(0, 0) != 0)
265 			err(1, "Can't daemonize");
266 		signal(SIGINT, SIG_IGN);
267 		signal(SIGQUIT, SIG_IGN);
268 		signal(SIGHUP, SIG_IGN);
269 	}
270 	signal(SIGTERM, rpctlssd_terminate);
271 	signal(SIGPIPE, SIG_IGN);
272 	signal(SIGHUP, rpctls_huphandler);
273 
274 	pidfile_write(rpctls_pfh);
275 
276 	memset(&sun, 0, sizeof sun);
277 	sun.sun_family = AF_LOCAL;
278 	unlink(_PATH_RPCTLSSDSOCK);
279 	strcpy(sun.sun_path, _PATH_RPCTLSSDSOCK);
280 	sun.sun_len = SUN_LEN(&sun);
281 	fd = socket(AF_LOCAL, SOCK_STREAM, 0);
282 	if (fd < 0) {
283 		if (rpctls_debug_level == 0) {
284 			syslog(LOG_ERR, "Can't create local rpctlssd socket");
285 			exit(1);
286 		}
287 		err(1, "Can't create local rpctlssd socket");
288 	}
289 	oldmask = umask(S_IXUSR|S_IRWXG|S_IRWXO);
290 	if (bind(fd, (struct sockaddr *)&sun, sun.sun_len) < 0) {
291 		if (rpctls_debug_level == 0) {
292 			syslog(LOG_ERR, "Can't bind local rpctlssd socket");
293 			exit(1);
294 		}
295 		err(1, "Can't bind local rpctlssd socket");
296 	}
297 	umask(oldmask);
298 	if (listen(fd, SOMAXCONN) < 0) {
299 		if (rpctls_debug_level == 0) {
300 			syslog(LOG_ERR,
301 			    "Can't listen on local rpctlssd socket");
302 			exit(1);
303 		}
304 		err(1, "Can't listen on local rpctlssd socket");
305 	}
306 	xprt = svc_vc_create(fd, RPC_MAXDATASIZE, RPC_MAXDATASIZE);
307 	if (!xprt) {
308 		if (rpctls_debug_level == 0) {
309 			syslog(LOG_ERR,
310 			    "Can't create transport for local rpctlssd socket");
311 			exit(1);
312 		}
313 		err(1, "Can't create transport for local rpctlssd socket");
314 	}
315 	if (!svc_reg(xprt, RPCTLSSD, RPCTLSSDVERS, rpctlssd_1, NULL)) {
316 		if (rpctls_debug_level == 0) {
317 			syslog(LOG_ERR,
318 			    "Can't register service for local rpctlssd socket");
319 			exit(1);
320 		}
321 		err(1, "Can't register service for local rpctlssd socket");
322 	}
323 
324 	rpctls_ctx = rpctls_setup_ssl(rpctls_certdir);
325 	if (rpctls_ctx == NULL) {
326 		if (rpctls_debug_level == 0) {
327 			syslog(LOG_ERR, "Can't create SSL context");
328 			exit(1);
329 		}
330 		err(1, "Can't create SSL context");
331 	}
332 	rpctls_gothup = false;
333 	LIST_INIT(&rpctls_ssllist);
334 
335 	rpctls_syscall(RPCTLS_SYSC_SRVSETPATH, _PATH_RPCTLSSDSOCK);
336 
337 	rpctls_svc_run();
338 
339 	rpctls_syscall(RPCTLS_SYSC_SRVSHUTDOWN, "");
340 
341 	SSL_CTX_free(rpctls_ctx);
342 	EVP_cleanup();
343 	return (0);
344 }
345 
346 bool_t
347 rpctlssd_null_1_svc(__unused void *argp, __unused void *result,
348     __unused struct svc_req *rqstp)
349 {
350 
351 	rpctls_verbose_out("rpctlssd_null_svc: done\n");
352 	return (TRUE);
353 }
354 
355 bool_t
356 rpctlssd_connect_1_svc(__unused void *argp,
357     struct rpctlssd_connect_res *result, __unused struct svc_req *rqstp)
358 {
359 	int ngrps, s;
360 	SSL *ssl;
361 	uint32_t flags;
362 	struct ssl_entry *newslp;
363 	uint32_t uid;
364 	uint32_t *gidp;
365 	X509 *cert;
366 
367 	rpctls_verbose_out("rpctlsd_connect_svc: started\n");
368 	memset(result, 0, sizeof(*result));
369 	/* Get the socket fd from the kernel. */
370 	s = rpctls_syscall(RPCTLS_SYSC_SRVSOCKET, "");
371 	if (s < 0)
372 		return (FALSE);
373 
374 	/* Do the server side of a TLS handshake. */
375 	gidp = calloc(NGROUPS, sizeof(*gidp));
376 	ssl = rpctls_server(rpctls_ctx, s, &flags, &uid, &ngrps, gidp, &cert);
377 	if (ssl == NULL) {
378 		free(gidp);
379 		rpctls_verbose_out("rpctlssd_connect_svc: ssl "
380 		    "accept failed\n");
381 		/*
382 		 * For RPC-over-TLS, this upcall is expected
383 		 * to close off the socket upon handshake failure.
384 		 */
385 		close(s);
386 		return (FALSE);
387 	} else {
388 		rpctls_verbose_out("rpctlssd_connect_svc: "
389 		    "succeeded flags=0x%x\n", flags);
390 		result->flags = flags;
391 		result->sec = rpctls_ssl_sec;
392 		result->usec = rpctls_ssl_usec;
393 		result->ssl = ++rpctls_ssl_refno;
394 		/* Hard to believe this could ever wrap around.. */
395 		if (rpctls_ssl_refno == 0)
396 			result->ssl = ++rpctls_ssl_refno;
397 		if ((flags & RPCTLS_FLAGS_CERTUSER) != 0) {
398 			result->uid = uid;
399 			result->gid.gid_len = ngrps;
400 			result->gid.gid_val = gidp;
401 		} else {
402 			result->uid = 0;
403 			result->gid.gid_len = 0;
404 			result->gid.gid_val = gidp;
405 		}
406 	}
407 
408 	/* Maintain list of all current SSL *'s */
409 	newslp = malloc(sizeof(*newslp));
410 	newslp->ssl = ssl;
411 	newslp->s = s;
412 	newslp->shutoff = false;
413 	newslp->refno = rpctls_ssl_refno;
414 	newslp->cert = cert;
415 	LIST_INSERT_HEAD(&rpctls_ssllist, newslp, next);
416 	return (TRUE);
417 }
418 
419 bool_t
420 rpctlssd_handlerecord_1_svc(struct rpctlssd_handlerecord_arg *argp,
421     struct rpctlssd_handlerecord_res *result, __unused struct svc_req *rqstp)
422 {
423 	struct ssl_entry *slp;
424 	int ret;
425 	char junk;
426 
427 	slp = NULL;
428 	if (argp->sec == rpctls_ssl_sec && argp->usec ==
429 	    rpctls_ssl_usec) {
430 		LIST_FOREACH(slp, &rpctls_ssllist, next) {
431 			if (slp->refno == argp->ssl)
432 				break;
433 		}
434 	}
435 
436 	if (slp != NULL) {
437 		rpctls_verbose_out("rpctlssd_handlerecord fd=%d\n",
438 		    slp->s);
439 		/*
440 		 * An SSL_read() of 0 bytes should fail, but it should
441 		 * handle the non-application data record before doing so.
442 		 */
443 		ret = SSL_read(slp->ssl, &junk, 0);
444 		if (ret <= 0) {
445 			/* Check to see if this was a close alert. */
446 			ret = SSL_get_shutdown(slp->ssl);
447 			if ((ret & (SSL_SENT_SHUTDOWN |
448 			    SSL_RECEIVED_SHUTDOWN)) == SSL_RECEIVED_SHUTDOWN)
449 				SSL_shutdown(slp->ssl);
450 		} else {
451 			if (rpctls_debug_level == 0)
452 				syslog(LOG_ERR, "SSL_read returned %d", ret);
453 			else
454 				fprintf(stderr, "SSL_read returned %d\n", ret);
455 		}
456 		result->reterr = RPCTLSERR_OK;
457 	} else
458 		result->reterr = RPCTLSERR_NOSSL;
459 	return (TRUE);
460 }
461 
462 bool_t
463 rpctlssd_disconnect_1_svc(struct rpctlssd_disconnect_arg *argp,
464     struct rpctlssd_disconnect_res *result, __unused struct svc_req *rqstp)
465 {
466 	struct ssl_entry *slp;
467 	int ret;
468 
469 	slp = NULL;
470 	if (argp->sec == rpctls_ssl_sec && argp->usec ==
471 	    rpctls_ssl_usec) {
472 		LIST_FOREACH(slp, &rpctls_ssllist, next) {
473 			if (slp->refno == argp->ssl)
474 				break;
475 		}
476 	}
477 
478 	if (slp != NULL) {
479 		rpctls_verbose_out("rpctlssd_disconnect fd=%d closed\n",
480 		    slp->s);
481 		LIST_REMOVE(slp, next);
482 		if (!slp->shutoff) {
483 			ret = SSL_get_shutdown(slp->ssl);
484 			/*
485 			 * Do an SSL_shutdown() unless a close alert has
486 			 * already been sent.
487 			 */
488 			if ((ret & SSL_SENT_SHUTDOWN) == 0)
489 				SSL_shutdown(slp->ssl);
490 		}
491 		SSL_free(slp->ssl);
492 		if (slp->cert != NULL)
493 			X509_free(slp->cert);
494 		/*
495 		 * For RPC-over-TLS, this upcall is expected
496 		 * to close off the socket.
497 		 */
498 		if (!slp->shutoff)
499 			shutdown(slp->s, SHUT_WR);
500 		close(slp->s);
501 		free(slp);
502 		result->reterr = RPCTLSERR_OK;
503 	} else
504 		result->reterr = RPCTLSERR_NOCLOSE;
505 	return (TRUE);
506 }
507 
508 int
509 rpctlssd_1_freeresult(__unused SVCXPRT *transp, xdrproc_t xdr_result,
510     caddr_t result)
511 {
512 	rpctlssd_connect_res *res;
513 
514 	if (xdr_result == (xdrproc_t)xdr_rpctlssd_connect_res) {
515 		res = (rpctlssd_connect_res *)(void *)result;
516 		free(res->gid.gid_val);
517 	}
518 	return (TRUE);
519 }
520 
521 static void
522 rpctlssd_terminate(int sig __unused)
523 {
524 	struct ssl_entry *slp;
525 
526 	rpctls_syscall(RPCTLS_SYSC_SRVSHUTDOWN, "");
527 	pidfile_remove(rpctls_pfh);
528 
529 	LIST_FOREACH(slp, &rpctls_ssllist, next)
530 		shutdown(slp->s, SHUT_RD);
531 	exit(0);
532 }
533 
534 /* Allow the handshake to proceed. */
535 static int
536 rpctls_verify_callback(__unused int preverify_ok,
537     __unused X509_STORE_CTX *x509_ctx)
538 {
539 
540 	return (1);
541 }
542 
543 static SSL_CTX *
544 rpctls_setup_ssl(const char *certdir)
545 {
546 	SSL_CTX *ctx;
547 	char path[PATH_MAX];
548 	size_t len, rlen;
549 	int ret;
550 
551 	SSL_library_init();
552 	SSL_load_error_strings();
553 	OpenSSL_add_all_algorithms();
554 
555 	ctx = SSL_CTX_new(TLS_server_method());
556 	if (ctx == NULL) {
557 		rpctls_verbose_out("rpctls_setup_ssl: SSL_CTX_new failed\n");
558 		return (NULL);
559 	}
560 	SSL_CTX_set_ecdh_auto(ctx, 1);
561 
562 	/*
563 	 * Set preferred ciphers, since KERN_TLS only supports a
564 	 * few of them.
565 	 */
566 	ret = SSL_CTX_set_cipher_list(ctx, _PREFERRED_CIPHERS);
567 	if (ret == 0) {
568 		rpctls_verbose_out("rpctls_setup_ssl: "
569 		    "SSL_CTX_set_cipher_list failed to set any ciphers\n");
570 		SSL_CTX_free(ctx);
571 		return (NULL);
572 	}
573 
574 	/* Get the cert.pem and certkey.pem files from the directory certdir. */
575 	len = strlcpy(path, certdir, sizeof(path));
576 	rlen = sizeof(path) - len;
577 	if (strlcpy(&path[len], "cert.pem", rlen) != 8) {
578 		SSL_CTX_free(ctx);
579 		return (NULL);
580 	}
581 	ret = SSL_CTX_use_certificate_file(ctx, path, SSL_FILETYPE_PEM);
582 	if (ret != 1) {
583 		rpctls_verbose_out("rpctls_setup_ssl: can't use certificate "
584 		    "file path=%s ret=%d\n", path, ret);
585 		SSL_CTX_free(ctx);
586 		return (NULL);
587 	}
588 	if (strlcpy(&path[len], "certkey.pem", rlen) != 11) {
589 		SSL_CTX_free(ctx);
590 		return (NULL);
591 	}
592 	ret = SSL_CTX_use_PrivateKey_file(ctx, path, SSL_FILETYPE_PEM);
593 	if (ret != 1) {
594 		rpctls_verbose_out("rpctls_setup_ssl: Can't use private "
595 		    "key path=%s ret=%d\n", path, ret);
596 		SSL_CTX_free(ctx);
597 		return (NULL);
598 	}
599 
600 	/* Set Mutual authentication, as required. */
601 	if (rpctls_do_mutual) {
602 		if (rpctls_verify_cafile != NULL ||
603 		    rpctls_verify_capath != NULL) {
604 			if (rpctls_crlfile != NULL) {
605 				ret = rpctls_loadcrlfile(ctx);
606 				if (ret == 0) {
607 					rpctls_verbose_out("rpctls_setup_ssl:"
608 					    " Load CRLfile failed\n");
609 					SSL_CTX_free(ctx);
610 					return (NULL);
611 				}
612 			}
613 #if OPENSSL_VERSION_NUMBER >= 0x30000000
614 			ret = 1;
615 			if (rpctls_verify_cafile != NULL)
616 				ret = SSL_CTX_load_verify_file(ctx,
617 				    rpctls_verify_cafile);
618 			if (ret != 0 && rpctls_verify_capath != NULL)
619 				ret = SSL_CTX_load_verify_dir(ctx,
620 				    rpctls_verify_capath);
621 #else
622 			ret = SSL_CTX_load_verify_locations(ctx,
623 			    rpctls_verify_cafile, rpctls_verify_capath);
624 #endif
625 			if (ret == 0) {
626 				rpctls_verbose_out("rpctls_setup_ssl: "
627 				    "Can't load verify locations\n");
628 				SSL_CTX_free(ctx);
629 				return (NULL);
630 			}
631 			if (rpctls_verify_cafile != NULL)
632 				SSL_CTX_set_client_CA_list(ctx,
633 				    SSL_load_client_CA_file(
634 			    rpctls_verify_cafile));
635 		}
636 		SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER,
637 		    rpctls_verify_callback);
638 	}
639 	SSL_CTX_clear_mode(ctx, SSL_MODE_NO_KTLS_TX | SSL_MODE_NO_KTLS_RX);
640 	return (ctx);
641 }
642 
643 static SSL *
644 rpctls_server(SSL_CTX *ctx, int s, uint32_t *flags, uint32_t *uidp,
645     int *ngrps, uint32_t *gidp, X509 **certp)
646 {
647 	SSL *ssl;
648 	X509 *cert;
649 	struct sockaddr *sad;
650 	struct sockaddr_storage ad;
651 	char hostnam[NI_MAXHOST];
652 	int gethostret, ret;
653 	char *cp, *cp2;
654 	long verfret;
655 
656 	*flags = 0;
657 	*certp = NULL;
658 	sad = (struct sockaddr *)&ad;
659 	ssl = SSL_new(ctx);
660 	if (ssl == NULL) {
661 		rpctls_verbose_out("rpctls_server: SSL_new failed\n");
662 		return (NULL);
663 	}
664 	if (SSL_set_fd(ssl, s) != 1) {
665 		rpctls_verbose_out("rpctls_server: SSL_set_fd failed\n");
666 		SSL_free(ssl);
667 		return (NULL);
668 	}
669 	ret = SSL_accept(ssl);
670 	if (ret != 1) {
671 		rpctls_verbose_out("rpctls_server: SSL_accept "
672 		    "failed ret=%d\n", ret);
673 		SSL_free(ssl);
674 		return (NULL);
675 	}
676 	*flags |= RPCTLS_FLAGS_HANDSHAKE;
677 	if (rpctls_do_mutual) {
678 		cert = SSL_get_peer_certificate(ssl);
679 		if (cert != NULL) {
680 			gethostret = rpctls_gethost(s, sad, hostnam,
681 			    sizeof(hostnam));
682 			if (gethostret == 0)
683 				hostnam[0] = '\0';
684 			cp2 = X509_NAME_oneline(
685 			    X509_get_subject_name(cert), NULL, 0);
686 			*flags |= RPCTLS_FLAGS_GOTCERT;
687 			verfret = SSL_get_verify_result(ssl);
688 			if (verfret != X509_V_OK) {
689 				cp = X509_NAME_oneline(
690 				    X509_get_issuer_name(cert), NULL, 0);
691 				if (rpctls_debug_level == 0)
692 					syslog(LOG_INFO | LOG_DAEMON,
693 					    "rpctls_server: client IP %s "
694 					    "issuerName=%s subjectName=%s"
695 					    " verify failed %s\n", hostnam,
696 					    cp, cp2,
697 					    X509_verify_cert_error_string(
698 					    verfret));
699 				else
700 					fprintf(stderr,
701 					    "rpctls_server: client IP %s "
702 					    "issuerName=%s subjectName=%s"
703 					    " verify failed %s\n", hostnam,
704 					    cp, cp2,
705 					    X509_verify_cert_error_string(
706 					    verfret));
707 			}
708 			if (verfret ==
709 			    X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT ||
710 			    verfret == X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN)
711 				*flags |= RPCTLS_FLAGS_SELFSIGNED;
712 			else if (verfret == X509_V_OK) {
713 				if (rpctls_comparehost) {
714 					ret = 0;
715 					if (gethostret != 0)
716 						ret = rpctls_checkhost(sad,
717 						    cert, rpctls_wildcard);
718 					if (ret != 1) {
719 						*flags |=
720 						    RPCTLS_FLAGS_DISABLED;
721 						rpctls_verbose_out(
722 						    "rpctls_server: "
723 						    "checkhost "
724 						    "failed\n");
725 					}
726 				}
727 				if (rpctls_cnuser) {
728 					ret = rpctls_cnname(cert, uidp,
729 					    ngrps, gidp);
730 					if (ret != 0)
731 						*flags |= RPCTLS_FLAGS_CERTUSER;
732 				}
733 				*flags |= RPCTLS_FLAGS_VERIFIED;
734 				*certp = cert;
735 				cert = NULL;
736 			}
737 			if (cert != NULL)
738 				X509_free(cert);
739 		} else
740 			rpctls_verbose_out("rpctls_server: "
741 			    "No peer certificate\n");
742 	}
743 
744 	/* Check to see that ktls is working for the connection. */
745 	ret = BIO_get_ktls_send(SSL_get_wbio(ssl));
746 	rpctls_verbose_out("rpctls_server: BIO_get_ktls_send=%d\n", ret);
747 	if (ret != 0) {
748 		ret = BIO_get_ktls_recv(SSL_get_rbio(ssl));
749 		rpctls_verbose_out("rpctls_server: BIO_get_ktls_recv=%d\n",
750 		    ret);
751 	}
752 	if (ret == 0) {
753 		if (rpctls_debug_level == 0)
754 			syslog(LOG_ERR, "ktls not working");
755 		else
756 			fprintf(stderr, "ktls not working\n");
757 		/*
758 		 * The handshake has completed, so all that can be
759 		 * done is disable the connection.
760 		 */
761 		*flags |= RPCTLS_FLAGS_DISABLED;
762 	}
763 
764 	return (ssl);
765 }
766 
767 /*
768  * Acquire the dnsname for this server.
769  */
770 static char *
771 rpctls_getdnsname(char *hostname)
772 {
773 	char *cp, *dnsname;
774 	struct addrinfo *aip, hints;
775 	int error;
776 
777 	dnsname = NULL;
778 	if (gethostname(hostname, MAXHOSTNAMELEN) == 0) {
779 		if ((cp = strchr(hostname, '.')) != NULL &&
780 		    *(cp + 1) != '\0') {
781 			*cp = '@';
782 			dnsname = cp;
783 		} else {
784 			memset((void *)&hints, 0, sizeof (hints));
785 			hints.ai_flags = AI_CANONNAME;
786 			error = getaddrinfo(hostname, NULL, &hints, &aip);
787 			if (error == 0) {
788 				if (aip->ai_canonname != NULL &&
789 				    (cp = strchr(aip->ai_canonname, '.')) !=
790 				    NULL && *(cp + 1) != '\0') {
791 					hostname[0] = '@';
792 					strlcpy(&hostname[1], cp + 1,
793 					    MAXHOSTNAMELEN + 1);
794 					dnsname = hostname;
795 				}
796 				freeaddrinfo(aip);
797 			}
798 		}
799 	}
800 	return (dnsname);
801 }
802 
803 /*
804  * Check for an otherName component of subjectAltName where the OID
805  * matches and the "domain" matches that of this server.
806  * If found, map "user" to a <uid, gidlist> for it.
807  */
808 static int
809 rpctls_cnname(X509 *cert, uint32_t *uidp, int *ngrps, uint32_t *gidp)
810 {
811 	char *cp, usern[1024 + 1];
812 	struct passwd *pwd;
813 	gid_t gids[NGROUPS];
814 	int i, j;
815 	GENERAL_NAMES *genlist;
816 	GENERAL_NAME *genname;
817 	OTHERNAME *val;
818 	size_t slen;
819 
820 	/* First, find the otherName in the subjectAltName. */
821 	genlist = X509_get_ext_d2i(cert, NID_subject_alt_name, NULL, NULL);
822 	if (genlist == NULL)
823 		return (0);
824 	cp = NULL;
825 	for (i = 0; i < sk_GENERAL_NAME_num(genlist); i++) {
826 		genname = sk_GENERAL_NAME_value(genlist, i);
827 		if (genname->type != GEN_OTHERNAME)
828 			continue;
829 		val = genname->d.otherName;
830 
831 		/* Check to see that it is the correct OID. */
832 		slen = i2t_ASN1_OBJECT(usern, sizeof(usern), val->type_id);
833 		if (slen != strlen(rpctls_cnuseroid) || memcmp(usern,
834 		    rpctls_cnuseroid, slen) != 0)
835 			continue;
836 
837 		/* Sanity check the otherName. */
838 		if (val->value->type != V_ASN1_UTF8STRING ||
839 		    val->value->value.utf8string->length < 3 ||
840 		    (size_t)val->value->value.utf8string->length > sizeof(usern)
841 		    - 1) {
842 			rpctls_verbose_out("rpctls_cnname: invalid cnuser "
843 			    "type=%d\n", val->value->type);
844 			continue;
845 		}
846 
847 		/* Look for a "user" in the otherName */
848 		memcpy(usern, val->value->value.utf8string->data,
849 		    val->value->value.utf8string->length);
850 		usern[val->value->value.utf8string->length] = '\0';
851 
852 		/* Now, look for the @dnsname suffix in the commonName. */
853 		cp = strcasestr(usern, rpctls_dnsname);
854 		if (cp == NULL)
855 			continue;
856 		if (*(cp + strlen(rpctls_dnsname)) != '\0') {
857 			cp = NULL;
858 			continue;
859 		}
860 		*cp = '\0';
861 		break;
862 	}
863 	if (cp == NULL)
864 		return (0);
865 
866 	/* See if the "user" is in the passwd database. */
867 	pwd = getpwnam(usern);
868 	if (pwd == NULL)
869 		return (0);
870 	*uidp = pwd->pw_uid;
871 	*ngrps = NGROUPS;
872 	if (getgrouplist(pwd->pw_name, pwd->pw_gid, gids, ngrps) < 0)
873 		return (0);
874 	rpctls_verbose_out("mapped user=%s ngrps=%d uid=%d\n", pwd->pw_name,
875 	    *ngrps, pwd->pw_uid);
876 	for (j = 0; j < *ngrps; j++)
877 		gidp[j] = gids[j];
878 	return (1);
879 }
880 
881 static void
882 rpctls_huphandler(int sig __unused)
883 {
884 
885 	rpctls_gothup = true;
886 }
887