xref: /freebsd/usr.sbin/rpc.tlsservd/rpc.tlsservd.c (revision 06c3fb2749bda94cb5201f81ffdb8fa6c3161b2e)
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  *
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/param.h>
36 #include <sys/types.h>
37 #include <sys/linker.h>
38 #include <sys/module.h>
39 #include <sys/queue.h>
40 #include <sys/stat.h>
41 #include <sys/sysctl.h>
42 #include <sys/syslog.h>
43 #include <sys/time.h>
44 #include <sys/wait.h>
45 #include <err.h>
46 #include <getopt.h>
47 #include <libutil.h>
48 #include <netdb.h>
49 #include <pwd.h>
50 #include <signal.h>
51 #include <stdarg.h>
52 #include <stdio.h>
53 #include <stdlib.h>
54 #include <stdbool.h>
55 #include <string.h>
56 #include <unistd.h>
57 
58 #include <rpc/rpc.h>
59 #include <rpc/rpc_com.h>
60 #include <rpc/rpcsec_tls.h>
61 
62 #include <openssl/opensslconf.h>
63 #include <openssl/bio.h>
64 #include <openssl/ssl.h>
65 #include <openssl/err.h>
66 #include <openssl/x509v3.h>
67 
68 #include "rpctlssd.h"
69 #include "rpc.tlscommon.h"
70 
71 #ifndef _PATH_RPCTLSSDSOCK
72 #define _PATH_RPCTLSSDSOCK	"/var/run/rpc.tlsservd.sock"
73 #endif
74 #ifndef	_PATH_CERTANDKEY
75 #define	_PATH_CERTANDKEY	"/etc/rpc.tlsservd/"
76 #endif
77 #ifndef	_PATH_RPCTLSSDPID
78 #define	_PATH_RPCTLSSDPID	"/var/run/rpc.tlsservd.pid"
79 #endif
80 #ifndef	_PREFERRED_CIPHERS
81 #define	_PREFERRED_CIPHERS	"AES128-GCM-SHA256"
82 #endif
83 
84 /* Global variables also used by rpc.tlscommon.c. */
85 int			rpctls_debug_level;
86 bool			rpctls_verbose;
87 SSL_CTX			*rpctls_ctx = NULL;
88 const char		*rpctls_verify_cafile = NULL;
89 const char		*rpctls_verify_capath = NULL;
90 char			*rpctls_crlfile = NULL;
91 bool			rpctls_gothup = false;
92 struct ssl_list		rpctls_ssllist;
93 
94 static struct pidfh	*rpctls_pfh = NULL;
95 static bool		rpctls_do_mutual = false;
96 static const char	*rpctls_certdir = _PATH_CERTANDKEY;
97 static bool		rpctls_comparehost = false;
98 static unsigned int	rpctls_wildcard = X509_CHECK_FLAG_NO_WILDCARDS;
99 static uint64_t		rpctls_ssl_refno = 0;
100 static uint64_t		rpctls_ssl_sec = 0;
101 static uint64_t		rpctls_ssl_usec = 0;
102 static bool		rpctls_cnuser = false;
103 static char		*rpctls_dnsname;
104 static const char	*rpctls_cnuseroid = "1.3.6.1.4.1.2238.1.1.1";
105 static const char	*rpctls_ciphers = NULL;
106 static int		rpctls_mintls = TLS1_3_VERSION;
107 static int		rpctls_procs = 1;
108 static char		*rpctls_sockname[RPCTLS_SRV_MAXNPROCS];
109 static pid_t		rpctls_workers[RPCTLS_SRV_MAXNPROCS - 1];
110 static bool		rpctls_im_a_worker = false;
111 
112 static void		rpctls_cleanup_term(int sig);
113 static SSL_CTX		*rpctls_setup_ssl(const char *certdir);
114 static SSL		*rpctls_server(SSL_CTX *ctx, int s,
115 			    uint32_t *flags, uint32_t *uidp,
116 			    int *ngrps, uint32_t *gidp, X509 **certp);
117 static int		rpctls_cnname(X509 *cert, uint32_t *uidp,
118 			    int *ngrps, uint32_t *gidp);
119 static char		*rpctls_getdnsname(char *dnsname);
120 static void		rpctls_huphandler(int sig __unused);
121 
122 extern void		rpctlssd_1(struct svc_req *rqstp, SVCXPRT *transp);
123 
124 static struct option longopts[] = {
125 	{ "allowtls1_2",	no_argument,		NULL,	'2' },
126 	{ "ciphers",		required_argument,	NULL,	'C' },
127 	{ "certdir",		required_argument,	NULL,	'D' },
128 	{ "debuglevel",		no_argument,		NULL,	'd' },
129 	{ "checkhost",		no_argument,		NULL,	'h' },
130 	{ "verifylocs",		required_argument,	NULL,	'l' },
131 	{ "mutualverf",		no_argument,		NULL,	'm' },
132 	{ "numdaemons",		required_argument,	NULL,	'N' },
133 	{ "domain",		required_argument,	NULL,	'n' },
134 	{ "verifydir",		required_argument,	NULL,	'p' },
135 	{ "crl",		required_argument,	NULL,	'r' },
136 	{ "certuser",		no_argument,		NULL,	'u' },
137 	{ "verbose",		no_argument,		NULL,	'v' },
138 	{ "multiwild",		no_argument,		NULL,	'W' },
139 	{ "singlewild",		no_argument,		NULL,	'w' },
140 	{ NULL,			0,			NULL,	0  }
141 };
142 
143 int
144 main(int argc, char **argv)
145 {
146 	/*
147 	 * We provide an RPC service on a local-domain socket. The
148 	 * kernel rpctls code will upcall to this daemon to do the initial
149 	 * TLS handshake.
150 	 */
151 	struct sockaddr_un sun;
152 	int ch, fd, i, mypos, oldmask;
153 	SVCXPRT *xprt;
154 	struct timeval tm;
155 	struct timezone tz;
156 	char hostname[MAXHOSTNAMELEN + 2];
157 	pid_t otherpid;
158 	bool tls_enable;
159 	size_t tls_enable_len;
160 	sigset_t signew;
161 
162 	/* Check that another rpctlssd isn't already running. */
163 	rpctls_pfh = pidfile_open(_PATH_RPCTLSSDPID, 0600, &otherpid);
164 	if (rpctls_pfh == NULL) {
165 		if (errno == EEXIST)
166 			errx(1, "rpctlssd already running, pid: %d.", otherpid);
167 		warn("cannot open or create pidfile");
168 	}
169 
170 	/* Check to see that the ktls is enabled. */
171 	tls_enable_len = sizeof(tls_enable);
172 	if (sysctlbyname("kern.ipc.tls.enable", &tls_enable, &tls_enable_len,
173 	    NULL, 0) != 0 || !tls_enable)
174 		errx(1, "Kernel TLS not enabled");
175 
176 	/* Get the time when this daemon is started. */
177 	gettimeofday(&tm, &tz);
178 	rpctls_ssl_sec = tm.tv_sec;
179 	rpctls_ssl_usec = tm.tv_usec;
180 
181 	/* Set the dns name for the server. */
182 	rpctls_dnsname = rpctls_getdnsname(hostname);
183 	if (rpctls_dnsname == NULL) {
184 		strcpy(hostname, "@default.domain");
185 		rpctls_dnsname = hostname;
186 	}
187 
188 	/* Initialize socket names. */
189 	for (i = 0; i < RPCTLS_SRV_MAXNPROCS; i++) {
190 		asprintf(&rpctls_sockname[i], "%s.%d", _PATH_RPCTLSSDSOCK, i);
191 		if (rpctls_sockname[i] == NULL)
192 			errx(1, "Cannot malloc socknames");
193 	}
194 
195 	rpctls_verbose = false;
196 	while ((ch = getopt_long(argc, argv, "2C:D:dhl:N:n:mp:r:uvWw", longopts,
197 	    NULL)) != -1) {
198 		switch (ch) {
199 		case '2':
200 			rpctls_mintls = TLS1_2_VERSION;
201 			break;
202 		case 'C':
203 			rpctls_ciphers = optarg;
204 			break;
205 		case 'D':
206 			rpctls_certdir = optarg;
207 			break;
208 		case 'd':
209 			rpctls_debug_level++;
210 			break;
211 		case 'h':
212 			rpctls_comparehost = true;
213 			break;
214 		case 'l':
215 			rpctls_verify_cafile = optarg;
216 			break;
217 		case 'm':
218 			rpctls_do_mutual = true;
219 			break;
220 		case 'N':
221 			rpctls_procs = atoi(optarg);
222 			if (rpctls_procs < 1 ||
223 			    rpctls_procs > RPCTLS_SRV_MAXNPROCS)
224 				errx(1, "numdaemons/-N must be between 1 and "
225 				    "%d", RPCTLS_SRV_MAXNPROCS);
226 			break;
227 		case 'n':
228 			hostname[0] = '@';
229 			strlcpy(&hostname[1], optarg, MAXHOSTNAMELEN + 1);
230 			rpctls_dnsname = hostname;
231 			break;
232 		case 'p':
233 			rpctls_verify_capath = optarg;
234 			break;
235 		case 'r':
236 			rpctls_crlfile = optarg;
237 			break;
238 		case 'u':
239 			rpctls_cnuser = true;
240 			break;
241 		case 'v':
242 			rpctls_verbose = true;
243 			break;
244 		case 'W':
245 			if (rpctls_wildcard != X509_CHECK_FLAG_NO_WILDCARDS)
246 				errx(1, "options -w and -W are mutually "
247 				    "exclusive");
248 			rpctls_wildcard = X509_CHECK_FLAG_MULTI_LABEL_WILDCARDS;
249 			break;
250 		case 'w':
251 			if (rpctls_wildcard != X509_CHECK_FLAG_NO_WILDCARDS)
252 				errx(1, "options -w and -W are mutually "
253 				    "exclusive");
254 			rpctls_wildcard = 0;
255 			break;
256 		default:
257 			fprintf(stderr, "usage: %s "
258 			    "[-2/--allowtls1_2] "
259 			    "[-C/--ciphers available_ciphers] "
260 			    "[-D/--certdir certdir] [-d/--debuglevel] "
261 			    "[-h/--checkhost] "
262 			    "[-l/--verifylocs CAfile] [-m/--mutualverf] "
263 			    "[-N/--numdaemons num] "
264 			    "[-n/--domain domain_name] "
265 			    "[-p/--verifydir CApath] [-r/--crl CRLfile] "
266 			    "[-u/--certuser] [-v/--verbose] [-W/--multiwild] "
267 			    "[-w/--singlewild]\n", argv[0]);
268 			exit(1);
269 		}
270 	}
271 	if (rpctls_do_mutual && rpctls_verify_cafile == NULL &&
272 	    rpctls_verify_capath == NULL)
273 		errx(1, "-m requires the -l <CAfile> and/or "
274 		    "-p <CApath> options");
275 	if (rpctls_comparehost && (!rpctls_do_mutual ||
276 	    (rpctls_verify_cafile == NULL && rpctls_verify_capath == NULL)))
277 		errx(1, "-h requires the -m plus the "
278 		    "-l <CAfile> and/or -p <CApath> options");
279 	if (!rpctls_comparehost && rpctls_wildcard !=
280 	    X509_CHECK_FLAG_NO_WILDCARDS)
281 		errx(1, "The -w or -W options require the -h option");
282 	if (rpctls_cnuser && (!rpctls_do_mutual ||
283 	    (rpctls_verify_cafile == NULL && rpctls_verify_capath == NULL)))
284 		errx(1, "-u requires the -m plus the "
285 		    "-l <CAfile> and/or -p <CApath> options");
286 
287 	if (modfind("krpc") < 0) {
288 		/* Not present in kernel, try loading it */
289 		if (kldload("krpc") < 0 || modfind("krpc") < 0)
290 			errx(1, "Kernel RPC is not available");
291 	}
292 
293 	for (i = 0; i < rpctls_procs - 1; i++)
294 		rpctls_workers[i] = -1;
295 	mypos = 0;
296 
297 	if (rpctls_debug_level == 0) {
298 		/*
299 		 * Temporarily block SIGTERM and SIGCHLD, so workers[] can't
300 		 * end up bogus.
301 		 */
302 		sigemptyset(&signew);
303 		sigaddset(&signew, SIGTERM);
304 		sigaddset(&signew, SIGCHLD);
305 		sigprocmask(SIG_BLOCK, &signew, NULL);
306 
307 		if (daemon(0, 0) != 0)
308 			err(1, "Can't daemonize");
309 		signal(SIGINT, SIG_IGN);
310 		signal(SIGQUIT, SIG_IGN);
311 	}
312 	signal(SIGPIPE, SIG_IGN);
313 	signal(SIGHUP, rpctls_huphandler);
314 	signal(SIGTERM, rpctls_cleanup_term);
315 	signal(SIGCHLD, rpctls_cleanup_term);
316 
317 	pidfile_write(rpctls_pfh);
318 
319 	rpctls_syscall(RPCTLS_SYSC_SRVSTARTUP, "");
320 
321 	if (rpctls_debug_level == 0) {
322 		/* Fork off the worker daemons. */
323 		for (i = 0; i < rpctls_procs - 1; i++) {
324 			rpctls_workers[i] = fork();
325 			if (rpctls_workers[i] == 0) {
326 				rpctls_im_a_worker = true;
327 				mypos = i + 1;
328 				setproctitle("server");
329 				break;
330 			} else if (rpctls_workers[i] < 0) {
331 				syslog(LOG_ERR, "fork: %m");
332 			}
333 		}
334 
335 		if (!rpctls_im_a_worker && rpctls_procs > 1)
336 			setproctitle("master");
337 	}
338 	sigemptyset(&signew);
339 	sigaddset(&signew, SIGTERM);
340 	sigaddset(&signew, SIGCHLD);
341 	sigprocmask(SIG_UNBLOCK, &signew, NULL);
342 
343 	memset(&sun, 0, sizeof sun);
344 	sun.sun_family = AF_LOCAL;
345 	unlink(rpctls_sockname[mypos]);
346 	strcpy(sun.sun_path, rpctls_sockname[mypos]);
347 	sun.sun_len = SUN_LEN(&sun);
348 	fd = socket(AF_LOCAL, SOCK_STREAM, 0);
349 	if (fd < 0) {
350 		if (rpctls_debug_level == 0) {
351 			syslog(LOG_ERR, "Can't create local rpctlssd socket");
352 			exit(1);
353 		}
354 		err(1, "Can't create local rpctlssd socket");
355 	}
356 	oldmask = umask(S_IXUSR|S_IRWXG|S_IRWXO);
357 	if (bind(fd, (struct sockaddr *)&sun, sun.sun_len) < 0) {
358 		if (rpctls_debug_level == 0) {
359 			syslog(LOG_ERR, "Can't bind local rpctlssd socket");
360 			exit(1);
361 		}
362 		err(1, "Can't bind local rpctlssd socket");
363 	}
364 	umask(oldmask);
365 	if (listen(fd, SOMAXCONN) < 0) {
366 		if (rpctls_debug_level == 0) {
367 			syslog(LOG_ERR,
368 			    "Can't listen on local rpctlssd socket");
369 			exit(1);
370 		}
371 		err(1, "Can't listen on local rpctlssd socket");
372 	}
373 	xprt = svc_vc_create(fd, RPC_MAXDATASIZE, RPC_MAXDATASIZE);
374 	if (!xprt) {
375 		if (rpctls_debug_level == 0) {
376 			syslog(LOG_ERR,
377 			    "Can't create transport for local rpctlssd socket");
378 			exit(1);
379 		}
380 		err(1, "Can't create transport for local rpctlssd socket");
381 	}
382 	if (!svc_reg(xprt, RPCTLSSD, RPCTLSSDVERS, rpctlssd_1, NULL)) {
383 		if (rpctls_debug_level == 0) {
384 			syslog(LOG_ERR,
385 			    "Can't register service for local rpctlssd socket");
386 			exit(1);
387 		}
388 		err(1, "Can't register service for local rpctlssd socket");
389 	}
390 
391 	rpctls_ctx = rpctls_setup_ssl(rpctls_certdir);
392 	if (rpctls_ctx == NULL) {
393 		if (rpctls_debug_level == 0) {
394 			syslog(LOG_ERR, "Can't create SSL context");
395 			exit(1);
396 		}
397 		err(1, "Can't create SSL context");
398 	}
399 	rpctls_gothup = false;
400 	LIST_INIT(&rpctls_ssllist);
401 
402 	if (rpctls_syscall(RPCTLS_SYSC_SRVSETPATH, rpctls_sockname[mypos]) < 0){
403 		if (rpctls_debug_level == 0) {
404 			syslog(LOG_ERR,
405 			    "Can't set upcall socket path=%s errno=%d",
406 			    rpctls_sockname[mypos], errno);
407 			exit(1);
408 		}
409 		err(1, "Can't set upcall socket path=%s",
410 		    rpctls_sockname[mypos]);
411 	}
412 
413 	rpctls_svc_run();
414 
415 	SSL_CTX_free(rpctls_ctx);
416 	return (0);
417 }
418 
419 bool_t
420 rpctlssd_null_1_svc(__unused void *argp, __unused void *result,
421     __unused struct svc_req *rqstp)
422 {
423 
424 	rpctls_verbose_out("rpctlssd_null_svc: done\n");
425 	return (TRUE);
426 }
427 
428 bool_t
429 rpctlssd_connect_1_svc(__unused void *argp,
430     struct rpctlssd_connect_res *result, __unused struct svc_req *rqstp)
431 {
432 	int ngrps, s;
433 	SSL *ssl;
434 	uint32_t flags;
435 	struct ssl_entry *newslp;
436 	uint32_t uid;
437 	uint32_t *gidp;
438 	X509 *cert;
439 
440 	rpctls_verbose_out("rpctlsd_connect_svc: started\n");
441 	memset(result, 0, sizeof(*result));
442 	/* Get the socket fd from the kernel. */
443 	s = rpctls_syscall(RPCTLS_SYSC_SRVSOCKET, "");
444 	if (s < 0)
445 		return (FALSE);
446 
447 	/* Do the server side of a TLS handshake. */
448 	gidp = calloc(NGROUPS, sizeof(*gidp));
449 	ssl = rpctls_server(rpctls_ctx, s, &flags, &uid, &ngrps, gidp, &cert);
450 	if (ssl == NULL) {
451 		free(gidp);
452 		rpctls_verbose_out("rpctlssd_connect_svc: ssl "
453 		    "accept failed\n");
454 		/*
455 		 * For RPC-over-TLS, this upcall is expected
456 		 * to close off the socket upon handshake failure.
457 		 */
458 		close(s);
459 		return (FALSE);
460 	} else {
461 		rpctls_verbose_out("rpctlssd_connect_svc: "
462 		    "succeeded flags=0x%x\n", flags);
463 		result->flags = flags;
464 		result->sec = rpctls_ssl_sec;
465 		result->usec = rpctls_ssl_usec;
466 		result->ssl = ++rpctls_ssl_refno;
467 		/* Hard to believe this could ever wrap around.. */
468 		if (rpctls_ssl_refno == 0)
469 			result->ssl = ++rpctls_ssl_refno;
470 		if ((flags & RPCTLS_FLAGS_CERTUSER) != 0) {
471 			result->uid = uid;
472 			result->gid.gid_len = ngrps;
473 			result->gid.gid_val = gidp;
474 		} else {
475 			result->uid = 0;
476 			result->gid.gid_len = 0;
477 			result->gid.gid_val = gidp;
478 		}
479 	}
480 
481 	/* Maintain list of all current SSL *'s */
482 	newslp = malloc(sizeof(*newslp));
483 	newslp->ssl = ssl;
484 	newslp->s = s;
485 	newslp->shutoff = false;
486 	newslp->refno = rpctls_ssl_refno;
487 	newslp->cert = cert;
488 	LIST_INSERT_HEAD(&rpctls_ssllist, newslp, next);
489 	return (TRUE);
490 }
491 
492 bool_t
493 rpctlssd_handlerecord_1_svc(struct rpctlssd_handlerecord_arg *argp,
494     struct rpctlssd_handlerecord_res *result, __unused struct svc_req *rqstp)
495 {
496 	struct ssl_entry *slp;
497 	int ret;
498 	char junk;
499 
500 	slp = NULL;
501 	if (argp->sec == rpctls_ssl_sec && argp->usec ==
502 	    rpctls_ssl_usec) {
503 		LIST_FOREACH(slp, &rpctls_ssllist, next) {
504 			if (slp->refno == argp->ssl)
505 				break;
506 		}
507 	}
508 
509 	if (slp != NULL) {
510 		rpctls_verbose_out("rpctlssd_handlerecord fd=%d\n",
511 		    slp->s);
512 		/*
513 		 * An SSL_read() of 0 bytes should fail, but it should
514 		 * handle the non-application data record before doing so.
515 		 */
516 		ret = SSL_read(slp->ssl, &junk, 0);
517 		if (ret <= 0) {
518 			/* Check to see if this was a close alert. */
519 			ret = SSL_get_shutdown(slp->ssl);
520 			if ((ret & (SSL_SENT_SHUTDOWN |
521 			    SSL_RECEIVED_SHUTDOWN)) == SSL_RECEIVED_SHUTDOWN)
522 				SSL_shutdown(slp->ssl);
523 		} else {
524 			if (rpctls_debug_level == 0)
525 				syslog(LOG_ERR, "SSL_read returned %d", ret);
526 			else
527 				fprintf(stderr, "SSL_read returned %d\n", ret);
528 		}
529 		result->reterr = RPCTLSERR_OK;
530 	} else
531 		result->reterr = RPCTLSERR_NOSSL;
532 	return (TRUE);
533 }
534 
535 bool_t
536 rpctlssd_disconnect_1_svc(struct rpctlssd_disconnect_arg *argp,
537     struct rpctlssd_disconnect_res *result, __unused struct svc_req *rqstp)
538 {
539 	struct ssl_entry *slp;
540 	int ret;
541 
542 	slp = NULL;
543 	if (argp->sec == rpctls_ssl_sec && argp->usec ==
544 	    rpctls_ssl_usec) {
545 		LIST_FOREACH(slp, &rpctls_ssllist, next) {
546 			if (slp->refno == argp->ssl)
547 				break;
548 		}
549 	}
550 
551 	if (slp != NULL) {
552 		rpctls_verbose_out("rpctlssd_disconnect fd=%d closed\n",
553 		    slp->s);
554 		LIST_REMOVE(slp, next);
555 		if (!slp->shutoff) {
556 			ret = SSL_get_shutdown(slp->ssl);
557 			/*
558 			 * Do an SSL_shutdown() unless a close alert has
559 			 * already been sent.
560 			 */
561 			if ((ret & SSL_SENT_SHUTDOWN) == 0)
562 				SSL_shutdown(slp->ssl);
563 		}
564 		SSL_free(slp->ssl);
565 		if (slp->cert != NULL)
566 			X509_free(slp->cert);
567 		/*
568 		 * For RPC-over-TLS, this upcall is expected
569 		 * to close off the socket.
570 		 */
571 		if (!slp->shutoff)
572 			shutdown(slp->s, SHUT_WR);
573 		close(slp->s);
574 		free(slp);
575 		result->reterr = RPCTLSERR_OK;
576 	} else
577 		result->reterr = RPCTLSERR_NOCLOSE;
578 	return (TRUE);
579 }
580 
581 int
582 rpctlssd_1_freeresult(__unused SVCXPRT *transp, xdrproc_t xdr_result,
583     caddr_t result)
584 {
585 	rpctlssd_connect_res *res;
586 
587 	if (xdr_result == (xdrproc_t)xdr_rpctlssd_connect_res) {
588 		res = (rpctlssd_connect_res *)(void *)result;
589 		free(res->gid.gid_val);
590 	}
591 	return (TRUE);
592 }
593 
594 /*
595  * cleanup_term() called via SIGTERM (or SIGCHLD if a child dies).
596  */
597 static void
598 rpctls_cleanup_term(int sig)
599 {
600 	struct ssl_entry *slp;
601 	int i, cnt;
602 
603 	if (rpctls_im_a_worker && sig == SIGCHLD)
604 		return;
605 	LIST_FOREACH(slp, &rpctls_ssllist, next)
606 		shutdown(slp->s, SHUT_RD);
607 	SSL_CTX_free(rpctls_ctx);
608 	EVP_cleanup();
609 
610 	if (rpctls_im_a_worker)
611 		exit(0);
612 
613 	/* I'm the server, so terminate the workers. */
614 	cnt = 0;
615 	for (i = 0; i < rpctls_procs - 1; i++) {
616 		if (rpctls_workers[i] != -1) {
617 			cnt++;
618 			kill(rpctls_workers[i], SIGTERM);
619 		}
620 	}
621 
622 	/*
623 	 * Wait for them to die.
624 	 */
625 	for (i = 0; i < cnt; i++)
626 		wait3(NULL, 0, NULL);
627 
628 	rpctls_syscall(RPCTLS_SYSC_SRVSHUTDOWN, "");
629 	pidfile_remove(rpctls_pfh);
630 
631 	exit(0);
632 }
633 
634 /* Allow the handshake to proceed. */
635 static int
636 rpctls_verify_callback(__unused int preverify_ok,
637     __unused X509_STORE_CTX *x509_ctx)
638 {
639 
640 	return (1);
641 }
642 
643 static SSL_CTX *
644 rpctls_setup_ssl(const char *certdir)
645 {
646 	SSL_CTX *ctx;
647 	char path[PATH_MAX];
648 	size_t len, rlen;
649 	int ret;
650 
651 	ctx = SSL_CTX_new(TLS_server_method());
652 	if (ctx == NULL) {
653 		rpctls_verbose_out("rpctls_setup_ssl: SSL_CTX_new failed\n");
654 		return (NULL);
655 	}
656 
657 	if (rpctls_ciphers != NULL) {
658 		/*
659 		 * Set available ciphers, since KERN_TLS only supports a
660 		 * few of them.  Normally, not doing this should be ok,
661 		 * since the library defaults will work.
662 		 */
663 		ret = SSL_CTX_set_ciphersuites(ctx, rpctls_ciphers);
664 		if (ret == 0) {
665 			rpctls_verbose_out("rpctls_setup_ssl: "
666 			    "SSL_CTX_set_ciphersuites failed: %s\n",
667 			    rpctls_ciphers);
668 			SSL_CTX_free(ctx);
669 			return (NULL);
670 		}
671 	}
672 
673 	ret = SSL_CTX_set_min_proto_version(ctx, rpctls_mintls);
674 	if (ret == 0) {
675 		rpctls_verbose_out("rpctls_setup_ssl: "
676 		    "SSL_CTX_set_min_proto_version failed\n");
677 		SSL_CTX_free(ctx);
678 		return (NULL);
679 	}
680 	ret = SSL_CTX_set_max_proto_version(ctx, TLS1_3_VERSION);
681 	if (ret == 0) {
682 		rpctls_verbose_out("rpctls_setup_ssl: "
683 		    "SSL_CTX_set_max_proto_version failed\n");
684 		SSL_CTX_free(ctx);
685 		return (NULL);
686 	}
687 
688 	/* Get the cert.pem and certkey.pem files from the directory certdir. */
689 	len = strlcpy(path, certdir, sizeof(path));
690 	rlen = sizeof(path) - len;
691 	if (strlcpy(&path[len], "cert.pem", rlen) != 8) {
692 		SSL_CTX_free(ctx);
693 		return (NULL);
694 	}
695 	ret = SSL_CTX_use_certificate_file(ctx, path, SSL_FILETYPE_PEM);
696 	if (ret != 1) {
697 		rpctls_verbose_out("rpctls_setup_ssl: can't use certificate "
698 		    "file path=%s ret=%d\n", path, ret);
699 		SSL_CTX_free(ctx);
700 		return (NULL);
701 	}
702 	if (strlcpy(&path[len], "certkey.pem", rlen) != 11) {
703 		SSL_CTX_free(ctx);
704 		return (NULL);
705 	}
706 	ret = SSL_CTX_use_PrivateKey_file(ctx, path, SSL_FILETYPE_PEM);
707 	if (ret != 1) {
708 		rpctls_verbose_out("rpctls_setup_ssl: Can't use private "
709 		    "key path=%s ret=%d\n", path, ret);
710 		SSL_CTX_free(ctx);
711 		return (NULL);
712 	}
713 
714 	/* Set Mutual authentication, as required. */
715 	if (rpctls_do_mutual) {
716 		if (rpctls_verify_cafile != NULL ||
717 		    rpctls_verify_capath != NULL) {
718 			if (rpctls_crlfile != NULL) {
719 				ret = rpctls_loadcrlfile(ctx);
720 				if (ret == 0) {
721 					rpctls_verbose_out("rpctls_setup_ssl:"
722 					    " Load CRLfile failed\n");
723 					SSL_CTX_free(ctx);
724 					return (NULL);
725 				}
726 			}
727 #if OPENSSL_VERSION_NUMBER >= 0x30000000
728 			ret = 1;
729 			if (rpctls_verify_cafile != NULL)
730 				ret = SSL_CTX_load_verify_file(ctx,
731 				    rpctls_verify_cafile);
732 			if (ret != 0 && rpctls_verify_capath != NULL)
733 				ret = SSL_CTX_load_verify_dir(ctx,
734 				    rpctls_verify_capath);
735 #else
736 			ret = SSL_CTX_load_verify_locations(ctx,
737 			    rpctls_verify_cafile, rpctls_verify_capath);
738 #endif
739 			if (ret == 0) {
740 				rpctls_verbose_out("rpctls_setup_ssl: "
741 				    "Can't load verify locations\n");
742 				SSL_CTX_free(ctx);
743 				return (NULL);
744 			}
745 			if (rpctls_verify_cafile != NULL)
746 				SSL_CTX_set_client_CA_list(ctx,
747 				    SSL_load_client_CA_file(
748 			    rpctls_verify_cafile));
749 		}
750 		SSL_CTX_set_verify(ctx, SSL_VERIFY_PEER,
751 		    rpctls_verify_callback);
752 	}
753 #ifdef SSL_OP_ENABLE_KTLS
754 	SSL_CTX_set_options(ctx, SSL_OP_ENABLE_KTLS);
755 #endif
756 #ifdef SSL_MODE_NO_KTLS_TX
757 	SSL_CTX_clear_mode(ctx, SSL_MODE_NO_KTLS_TX | SSL_MODE_NO_KTLS_RX);
758 #endif
759 	return (ctx);
760 }
761 
762 static SSL *
763 rpctls_server(SSL_CTX *ctx, int s, uint32_t *flags, uint32_t *uidp,
764     int *ngrps, uint32_t *gidp, X509 **certp)
765 {
766 	SSL *ssl;
767 	X509 *cert;
768 	struct sockaddr *sad;
769 	struct sockaddr_storage ad;
770 	char hostnam[NI_MAXHOST];
771 	int gethostret, ret;
772 	char *cp, *cp2;
773 	long verfret;
774 
775 	*flags = 0;
776 	*certp = NULL;
777 	sad = (struct sockaddr *)&ad;
778 	ssl = SSL_new(ctx);
779 	if (ssl == NULL) {
780 		rpctls_verbose_out("rpctls_server: SSL_new failed\n");
781 		return (NULL);
782 	}
783 	if (SSL_set_fd(ssl, s) != 1) {
784 		rpctls_verbose_out("rpctls_server: SSL_set_fd failed\n");
785 		SSL_free(ssl);
786 		return (NULL);
787 	}
788 	ret = SSL_accept(ssl);
789 	if (ret != 1) {
790 		rpctls_verbose_out("rpctls_server: SSL_accept "
791 		    "failed ret=%d\n", ret);
792 		SSL_free(ssl);
793 		return (NULL);
794 	}
795 	*flags |= RPCTLS_FLAGS_HANDSHAKE;
796 	if (rpctls_verbose) {
797 		gethostret = rpctls_gethost(s, sad, hostnam, sizeof(hostnam));
798 		if (gethostret == 0)
799 			hostnam[0] = '\0';
800 		rpctls_verbose_out("rpctls_server: SSL handshake ok for host %s"
801 		    " <%s %s>\n", hostnam, SSL_get_version(ssl),
802 		    SSL_get_cipher(ssl));
803 	}
804 	if (rpctls_do_mutual) {
805 #if OPENSSL_VERSION_NUMBER >= 0x30000000
806 		cert = SSL_get1_peer_certificate(ssl);
807 #else
808 		cert = SSL_get_peer_certificate(ssl);
809 #endif
810 		if (cert != NULL) {
811 			if (!rpctls_verbose) {
812 				gethostret = rpctls_gethost(s, sad, hostnam,
813 				    sizeof(hostnam));
814 				if (gethostret == 0)
815 					hostnam[0] = '\0';
816 			}
817 			cp2 = X509_NAME_oneline(
818 			    X509_get_subject_name(cert), NULL, 0);
819 			*flags |= RPCTLS_FLAGS_GOTCERT;
820 			verfret = SSL_get_verify_result(ssl);
821 			if (verfret != X509_V_OK) {
822 				cp = X509_NAME_oneline(
823 				    X509_get_issuer_name(cert), NULL, 0);
824 				if (rpctls_debug_level == 0)
825 					syslog(LOG_INFO | LOG_DAEMON,
826 					    "rpctls_server: client IP %s "
827 					    "issuerName=%s subjectName=%s"
828 					    " verify failed %s\n", hostnam,
829 					    cp, cp2,
830 					    X509_verify_cert_error_string(
831 					    verfret));
832 				else
833 					fprintf(stderr,
834 					    "rpctls_server: client IP %s "
835 					    "issuerName=%s subjectName=%s"
836 					    " verify failed %s\n", hostnam,
837 					    cp, cp2,
838 					    X509_verify_cert_error_string(
839 					    verfret));
840 			}
841 			if (verfret ==
842 			    X509_V_ERR_DEPTH_ZERO_SELF_SIGNED_CERT ||
843 			    verfret == X509_V_ERR_SELF_SIGNED_CERT_IN_CHAIN)
844 				*flags |= RPCTLS_FLAGS_SELFSIGNED;
845 			else if (verfret == X509_V_OK) {
846 				if (rpctls_comparehost) {
847 					ret = 0;
848 					if (gethostret != 0)
849 						ret = rpctls_checkhost(sad,
850 						    cert, rpctls_wildcard);
851 					if (ret != 1) {
852 						*flags |=
853 						    RPCTLS_FLAGS_DISABLED;
854 						rpctls_verbose_out(
855 						    "rpctls_server: "
856 						    "checkhost "
857 						    "failed\n");
858 					}
859 				}
860 				if (rpctls_cnuser) {
861 					ret = rpctls_cnname(cert, uidp,
862 					    ngrps, gidp);
863 					if (ret != 0)
864 						*flags |= RPCTLS_FLAGS_CERTUSER;
865 				}
866 				*flags |= RPCTLS_FLAGS_VERIFIED;
867 				*certp = cert;
868 				cert = NULL;
869 			}
870 			if (cert != NULL)
871 				X509_free(cert);
872 		} else
873 			rpctls_verbose_out("rpctls_server: "
874 			    "No peer certificate\n");
875 	}
876 
877 	/* Check to see that ktls is working for the connection. */
878 	ret = BIO_get_ktls_send(SSL_get_wbio(ssl));
879 	rpctls_verbose_out("rpctls_server: BIO_get_ktls_send=%d\n", ret);
880 	if (ret != 0) {
881 		ret = BIO_get_ktls_recv(SSL_get_rbio(ssl));
882 		rpctls_verbose_out("rpctls_server: BIO_get_ktls_recv=%d\n",
883 		    ret);
884 	}
885 	if (ret == 0) {
886 		if (rpctls_debug_level == 0)
887 			syslog(LOG_ERR, "ktls not working");
888 		else
889 			fprintf(stderr, "ktls not working\n");
890 		/*
891 		 * The handshake has completed, so all that can be
892 		 * done is disable the connection.
893 		 */
894 		*flags |= RPCTLS_FLAGS_DISABLED;
895 	}
896 
897 	return (ssl);
898 }
899 
900 /*
901  * Acquire the dnsname for this server.
902  */
903 static char *
904 rpctls_getdnsname(char *hostname)
905 {
906 	char *cp, *dnsname;
907 	struct addrinfo *aip, hints;
908 	int error;
909 
910 	dnsname = NULL;
911 	if (gethostname(hostname, MAXHOSTNAMELEN) == 0) {
912 		if ((cp = strchr(hostname, '.')) != NULL &&
913 		    *(cp + 1) != '\0') {
914 			*cp = '@';
915 			dnsname = cp;
916 		} else {
917 			memset((void *)&hints, 0, sizeof (hints));
918 			hints.ai_flags = AI_CANONNAME;
919 			error = getaddrinfo(hostname, NULL, &hints, &aip);
920 			if (error == 0) {
921 				if (aip->ai_canonname != NULL &&
922 				    (cp = strchr(aip->ai_canonname, '.')) !=
923 				    NULL && *(cp + 1) != '\0') {
924 					hostname[0] = '@';
925 					strlcpy(&hostname[1], cp + 1,
926 					    MAXHOSTNAMELEN + 1);
927 					dnsname = hostname;
928 				}
929 				freeaddrinfo(aip);
930 			}
931 		}
932 	}
933 	return (dnsname);
934 }
935 
936 /*
937  * Check for an otherName component of subjectAltName where the OID
938  * matches and the "domain" matches that of this server.
939  * If found, map "user" to a <uid, gidlist> for it.
940  */
941 static int
942 rpctls_cnname(X509 *cert, uint32_t *uidp, int *ngrps, uint32_t *gidp)
943 {
944 	char *cp, usern[1024 + 1];
945 	struct passwd *pwd;
946 	gid_t gids[NGROUPS];
947 	int i, j;
948 	GENERAL_NAMES *genlist;
949 	GENERAL_NAME *genname;
950 	OTHERNAME *val;
951 	size_t slen;
952 
953 	/* First, find the otherName in the subjectAltName. */
954 	genlist = X509_get_ext_d2i(cert, NID_subject_alt_name, NULL, NULL);
955 	if (genlist == NULL)
956 		return (0);
957 	cp = NULL;
958 	for (i = 0; i < sk_GENERAL_NAME_num(genlist); i++) {
959 		genname = sk_GENERAL_NAME_value(genlist, i);
960 		if (genname->type != GEN_OTHERNAME)
961 			continue;
962 		val = genname->d.otherName;
963 
964 		/* Check to see that it is the correct OID. */
965 		slen = i2t_ASN1_OBJECT(usern, sizeof(usern), val->type_id);
966 		if (slen != strlen(rpctls_cnuseroid) || memcmp(usern,
967 		    rpctls_cnuseroid, slen) != 0)
968 			continue;
969 
970 		/* Sanity check the otherName. */
971 		if (val->value->type != V_ASN1_UTF8STRING ||
972 		    val->value->value.utf8string->length < 3 ||
973 		    (size_t)val->value->value.utf8string->length > sizeof(usern)
974 		    - 1) {
975 			rpctls_verbose_out("rpctls_cnname: invalid cnuser "
976 			    "type=%d\n", val->value->type);
977 			continue;
978 		}
979 
980 		/* Look for a "user" in the otherName */
981 		memcpy(usern, val->value->value.utf8string->data,
982 		    val->value->value.utf8string->length);
983 		usern[val->value->value.utf8string->length] = '\0';
984 
985 		/* Now, look for the @dnsname suffix in the commonName. */
986 		cp = strcasestr(usern, rpctls_dnsname);
987 		if (cp == NULL)
988 			continue;
989 		if (*(cp + strlen(rpctls_dnsname)) != '\0') {
990 			cp = NULL;
991 			continue;
992 		}
993 		*cp = '\0';
994 		break;
995 	}
996 	if (cp == NULL)
997 		return (0);
998 
999 	/* See if the "user" is in the passwd database. */
1000 	pwd = getpwnam(usern);
1001 	if (pwd == NULL)
1002 		return (0);
1003 	*uidp = pwd->pw_uid;
1004 	*ngrps = NGROUPS;
1005 	if (getgrouplist(pwd->pw_name, pwd->pw_gid, gids, ngrps) < 0)
1006 		return (0);
1007 	rpctls_verbose_out("mapped user=%s ngrps=%d uid=%d\n", pwd->pw_name,
1008 	    *ngrps, pwd->pw_uid);
1009 	for (j = 0; j < *ngrps; j++)
1010 		gidp[j] = gids[j];
1011 	return (1);
1012 }
1013 
1014 static void
1015 rpctls_huphandler(int sig __unused)
1016 {
1017 
1018 	rpctls_gothup = true;
1019 }
1020