xref: /illumos-gate/usr/src/lib/libnsl/rpc/svc_generic.c (revision 8b80e8cb6855118d46f605e91b5ed4ce83417395)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License (the "License").
6  * You may not use this file except in compliance with the License.
7  *
8  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9  * or http://www.opensolaris.org/os/licensing.
10  * See the License for the specific language governing permissions
11  * and limitations under the License.
12  *
13  * When distributing Covered Code, include this CDDL HEADER in each
14  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15  * If applicable, add the following below this CDDL HEADER, with the
16  * fields enclosed by brackets "[]" replaced with your own identifying
17  * information: Portions Copyright [yyyy] [name of copyright owner]
18  *
19  * CDDL HEADER END
20  */
21 
22 /*
23  * Copyright 2006 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 /*	Copyright (c) 1988 AT&T */
28 /*	All Rights Reserved   */
29 
30 #pragma ident	"%Z%%M%	%I%	%E% SMI"
31 
32 /*
33  * svc_generic.c, Server side for RPC.
34  *
35  */
36 
37 #include "mt.h"
38 #include <stdlib.h>
39 #include <sys/socket.h>
40 #include <netinet/in.h>
41 #include <netinet/tcp.h>
42 #include <netinet/udp.h>
43 #include <inttypes.h>
44 #include "rpc_mt.h"
45 #include <stdio.h>
46 #include <rpc/rpc.h>
47 #include <sys/types.h>
48 #include <errno.h>
49 #include <syslog.h>
50 #include <rpc/nettype.h>
51 #include <malloc.h>
52 #include <string.h>
53 #include <stropts.h>
54 #include <tsol/label.h>
55 #include <nfs/nfs.h>
56 #include <nfs/nfs_acl.h>
57 #include <rpcsvc/mount.h>
58 #include <rpcsvc/nsm_addr.h>
59 #include <rpcsvc/rquota.h>
60 #include <rpcsvc/sm_inter.h>
61 #include <rpcsvc/nlm_prot.h>
62 
63 extern int __svc_vc_setflag(SVCXPRT *, int);
64 
65 extern SVCXPRT *svc_dg_create_private(int, uint_t, uint_t);
66 extern SVCXPRT *svc_vc_create_private(int, uint_t, uint_t);
67 extern SVCXPRT *svc_fd_create_private(int, uint_t, uint_t);
68 
69 extern bool_t __svc_add_to_xlist(SVCXPRT_LIST **, SVCXPRT *, mutex_t *);
70 extern void __svc_free_xlist(SVCXPRT_LIST **, mutex_t *);
71 
72 extern bool_t __rpc_try_doors(const char *, bool_t *);
73 
74 extern int use_portmapper;
75 
76 /*
77  * The highest level interface for server creation.
78  * It tries for all the nettokens in that particular class of token
79  * and returns the number of handles it can create and/or find.
80  *
81  * It creates a link list of all the handles it could create.
82  * If svc_create() is called multiple times, it uses the handle
83  * created earlier instead of creating a new handle every time.
84  */
85 
86 /* VARIABLES PROTECTED BY xprtlist_lock: xprtlist */
87 
88 SVCXPRT_LIST *_svc_xprtlist = NULL;
89 extern mutex_t xprtlist_lock;
90 
91 static SVCXPRT * svc_tli_create_common(int, const struct netconfig *,
92     const struct t_bind *, uint_t, uint_t, boolean_t);
93 
94 boolean_t
95 is_multilevel(rpcprog_t prognum)
96 {
97 	/* This is a list of identified multilevel service provider */
98 	if ((prognum == MOUNTPROG) || (prognum == NFS_PROGRAM) ||
99 	    (prognum == NFS_ACL_PROGRAM) || (prognum == NLM_PROG) ||
100 	    (prognum == NSM_ADDR_PROGRAM) || (prognum == RQUOTAPROG) ||
101 	    (prognum == SM_PROG))
102 		return (B_TRUE);
103 
104 	return (B_FALSE);
105 }
106 
107 void
108 __svc_free_xprtlist(void)
109 {
110 	__svc_free_xlist(&_svc_xprtlist, &xprtlist_lock);
111 }
112 
113 int
114 svc_create(void (*dispatch)(), const rpcprog_t prognum, const rpcvers_t versnum,
115 							const char *nettype)
116 {
117 	SVCXPRT_LIST *l;
118 	int num = 0;
119 	SVCXPRT *xprt;
120 	struct netconfig *nconf;
121 	void *handle;
122 	bool_t try_others;
123 
124 	/*
125 	 * Check if service should register over doors transport.
126 	 */
127 	if (__rpc_try_doors(nettype, &try_others)) {
128 		if (svc_door_create(dispatch, prognum, versnum, 0) == NULL)
129 			(void) syslog(LOG_ERR,
130 				"svc_create: could not register over doors");
131 		else
132 			num++;
133 	}
134 	if (!try_others)
135 		return (num);
136 	if ((handle = __rpc_setconf((char *)nettype)) == NULL) {
137 		(void) syslog(LOG_ERR, "svc_create: unknown protocol");
138 		return (0);
139 	}
140 	while (nconf = __rpc_getconf(handle)) {
141 		(void) mutex_lock(&xprtlist_lock);
142 		for (l = _svc_xprtlist; l; l = l->next) {
143 			if (strcmp(l->xprt->xp_netid, nconf->nc_netid) == 0) {
144 				/*
145 				 * Note that if we're using a portmapper
146 				 * instead of rpcbind then we can't do an
147 				 * unregister operation here.
148 				 *
149 				 * The reason is that the portmapper unset
150 				 * operation removes all the entries for a
151 				 * given program/version regardelss of
152 				 * transport protocol.
153 				 *
154 				 * The caller of this routine needs to ensure
155 				 * that __pmap_unset() has been called for all
156 				 * program/version service pairs they plan
157 				 * to support before they start registering
158 				 * each program/version/protocol triplet.
159 				 */
160 				if (!use_portmapper)
161 					(void) rpcb_unset(prognum,
162 					    versnum, nconf);
163 				if (svc_reg(l->xprt, prognum, versnum,
164 					dispatch, nconf) == FALSE)
165 					(void) syslog(LOG_ERR,
166 		"svc_create: could not register prog %d vers %d on %s",
167 					prognum, versnum, nconf->nc_netid);
168 				else
169 					num++;
170 				break;
171 			}
172 		}
173 		(void) mutex_unlock(&xprtlist_lock);
174 		if (l == NULL) {
175 			/* It was not found. Now create a new one */
176 			xprt = svc_tp_create(dispatch, prognum, versnum, nconf);
177 			if (xprt) {
178 				if (!__svc_add_to_xlist(&_svc_xprtlist, xprt,
179 							&xprtlist_lock)) {
180 					(void) syslog(LOG_ERR,
181 						"svc_create: no memory");
182 					return (0);
183 				}
184 				num++;
185 			}
186 		}
187 	}
188 	__rpc_endconf(handle);
189 	/*
190 	 * In case of num == 0; the error messages are generated by the
191 	 * underlying layers; and hence not needed here.
192 	 */
193 	return (num);
194 }
195 
196 /*
197  * The high level interface to svc_tli_create().
198  * It tries to create a server for "nconf" and registers the service
199  * with the rpcbind. It calls svc_tli_create();
200  */
201 SVCXPRT *
202 svc_tp_create(void (*dispatch)(), const rpcprog_t prognum,
203 			const rpcvers_t versnum, const struct netconfig *nconf)
204 {
205 	SVCXPRT *xprt;
206 	boolean_t anon_mlp = B_FALSE;
207 
208 	if (nconf == NULL) {
209 		(void) syslog(LOG_ERR,
210 	"svc_tp_create: invalid netconfig structure for prog %d vers %d",
211 				prognum, versnum);
212 		return (NULL);
213 	}
214 
215 	/* Some programs need to allocate MLP for multilevel services */
216 	if (is_system_labeled() && is_multilevel(prognum))
217 		anon_mlp = B_TRUE;
218 	xprt = svc_tli_create_common(RPC_ANYFD, nconf, NULL, 0, 0, anon_mlp);
219 	if (xprt == NULL)
220 		return (NULL);
221 
222 	/*
223 	 * Note that if we're using a portmapper
224 	 * instead of rpcbind then we can't do an
225 	 * unregister operation here.
226 	 *
227 	 * The reason is that the portmapper unset
228 	 * operation removes all the entries for a
229 	 * given program/version regardelss of
230 	 * transport protocol.
231 	 *
232 	 * The caller of this routine needs to ensure
233 	 * that __pmap_unset() has been called for all
234 	 * program/version service pairs they plan
235 	 * to support before they start registering
236 	 * each program/version/protocol triplet.
237 	 */
238 	if (!use_portmapper)
239 		(void) rpcb_unset(prognum, versnum, (struct netconfig *)nconf);
240 	if (svc_reg(xprt, prognum, versnum, dispatch, nconf) == FALSE) {
241 		(void) syslog(LOG_ERR,
242 		"svc_tp_create: Could not register prog %d vers %d on %s",
243 				prognum, versnum, nconf->nc_netid);
244 		SVC_DESTROY(xprt);
245 		return (NULL);
246 	}
247 	return (xprt);
248 }
249 
250 SVCXPRT *
251 svc_tli_create(const int fd, const struct netconfig *nconf,
252     const struct t_bind *bindaddr, const uint_t sendsz, const uint_t recvsz)
253 {
254 	return (svc_tli_create_common(fd, nconf, bindaddr, sendsz, recvsz, 0));
255 }
256 
257 /*
258  * If fd is RPC_ANYFD, then it opens a fd for the given transport
259  * provider (nconf cannot be NULL then). If the t_state is T_UNBND and
260  * bindaddr is NON-NULL, it performs a t_bind using the bindaddr. For
261  * NULL bindadr and Connection oriented transports, the value of qlen
262  * is set arbitrarily.
263  *
264  * If sendsz or recvsz are zero, their default values are chosen.
265  */
266 SVCXPRT *
267 svc_tli_create_common(const int ofd, const struct netconfig *nconf,
268 	const struct t_bind *bindaddr, const uint_t sendsz,
269 	const uint_t recvsz, boolean_t mlp_flag)
270 {
271 	SVCXPRT *xprt = NULL;		/* service handle */
272 	struct t_info tinfo;		/* transport info */
273 	struct t_bind *tres = NULL;	/* bind info */
274 	bool_t madefd = FALSE;		/* whether fd opened here  */
275 	int state;			/* state of the transport provider */
276 	int fd = ofd;
277 
278 	if (fd == RPC_ANYFD) {
279 		if (nconf == NULL) {
280 			(void) syslog(LOG_ERR,
281 			    "svc_tli_create: invalid netconfig");
282 			return (NULL);
283 		}
284 		fd = t_open(nconf->nc_device, O_RDWR, &tinfo);
285 		if (fd == -1) {
286 			char errorstr[100];
287 
288 			__tli_sys_strerror(errorstr, sizeof (errorstr),
289 					t_errno, errno);
290 			(void) syslog(LOG_ERR,
291 			"svc_tli_create: could not open connection for %s: %s",
292 					nconf->nc_netid, errorstr);
293 			return (NULL);
294 		}
295 		madefd = TRUE;
296 		state = T_UNBND;
297 	} else {
298 		/*
299 		 * It is an open descriptor. Sync it & get the transport info.
300 		 */
301 		if ((state = t_sync(fd)) == -1) {
302 			char errorstr[100];
303 
304 			__tli_sys_strerror(errorstr, sizeof (errorstr),
305 					t_errno, errno);
306 			(void) syslog(LOG_ERR,
307 		"svc_tli_create: could not do t_sync: %s",
308 					errorstr);
309 			return (NULL);
310 		}
311 		if (t_getinfo(fd, &tinfo) == -1) {
312 			char errorstr[100];
313 
314 			__tli_sys_strerror(errorstr, sizeof (errorstr),
315 					t_errno, errno);
316 			(void) syslog(LOG_ERR,
317 		"svc_tli_create: could not get transport information: %s",
318 				    errorstr);
319 			return (NULL);
320 		}
321 		/* Enable options of returning the ip's for udp */
322 		if (nconf) {
323 		    int ret = 0;
324 		    if (strcmp(nconf->nc_netid, "udp6") == 0) {
325 			ret = __rpc_tli_set_options(fd, IPPROTO_IPV6,
326 					IPV6_RECVPKTINFO, 1);
327 			if (ret < 0) {
328 			    char errorstr[100];
329 
330 			    __tli_sys_strerror(errorstr, sizeof (errorstr),
331 					t_errno, errno);
332 			    (void) syslog(LOG_ERR,
333 				"svc_tli_create: IPV6_RECVPKTINFO(1): %s",
334 					errorstr);
335 			    return (NULL);
336 			}
337 		    } else if (strcmp(nconf->nc_netid, "udp") == 0) {
338 			ret = __rpc_tli_set_options(fd, IPPROTO_IP,
339 					IP_RECVDSTADDR, 1);
340 			if (ret < 0) {
341 			    char errorstr[100];
342 
343 			    __tli_sys_strerror(errorstr, sizeof (errorstr),
344 					t_errno, errno);
345 			    (void) syslog(LOG_ERR,
346 				"svc_tli_create: IP_RECVDSTADDR(1): %s",
347 					errorstr);
348 			    return (NULL);
349 			}
350 		    }
351 		}
352 	}
353 
354 	/*
355 	 * If the fd is unbound, try to bind it.
356 	 * In any case, try to get its bound info in tres
357 	 */
358 /* LINTED pointer alignment */
359 	tres = (struct t_bind *)t_alloc(fd, T_BIND, T_ADDR);
360 	if (tres == NULL) {
361 		(void) syslog(LOG_ERR, "svc_tli_create: No memory!");
362 		goto freedata;
363 	}
364 
365 	switch (state) {
366 		bool_t tcp, exclbind;
367 	case T_UNBND:
368 		/* If this is a labeled system, then ask for an MLP */
369 		if (is_system_labeled() &&
370 		    (strcmp(nconf->nc_protofmly, NC_INET) == 0 ||
371 		    strcmp(nconf->nc_protofmly, NC_INET6) == 0)) {
372 			(void) __rpc_tli_set_options(fd, SOL_SOCKET,
373 			    SO_RECVUCRED, 1);
374 			if (mlp_flag)
375 				(void) __rpc_tli_set_options(fd, SOL_SOCKET,
376 				    SO_ANON_MLP, 1);
377 		}
378 
379 		/*
380 		 * SO_EXCLBIND has the following properties
381 		 *    - an fd bound to port P via IPv4 will prevent an IPv6
382 		 *    bind to port P (and vice versa)
383 		 *    - an fd bound to a wildcard IP address for port P will
384 		 *    prevent a more specific IP address bind to port P
385 		 *    (see {tcp,udp}.c for details)
386 		 *
387 		 * We use the latter property to prevent hijacking of RPC
388 		 * services that reside at non-privileged ports.
389 		 */
390 		tcp = nconf ? (strcmp(nconf->nc_proto, NC_TCP) == 0) : 0;
391 		if (nconf &&
392 		    (tcp || (strcmp(nconf->nc_proto, NC_UDP) == 0)) &&
393 		    rpc_control(__RPC_SVC_EXCLBIND_GET, &exclbind)) {
394 			if (exclbind) {
395 				if (__rpc_tli_set_options(fd, SOL_SOCKET,
396 				    SO_EXCLBIND, 1) < 0) {
397 					syslog(LOG_ERR,
398 			    "svc_tli_create: can't set EXCLBIND [netid='%s']",
399 					    nconf->nc_netid);
400 					goto freedata;
401 				}
402 			}
403 		}
404 		if (bindaddr) {
405 			if (t_bind(fd, (struct t_bind *)bindaddr,
406 								tres) == -1) {
407 				char errorstr[100];
408 
409 				__tli_sys_strerror(errorstr, sizeof (errorstr),
410 						t_errno, errno);
411 				(void) syslog(LOG_ERR,
412 					"svc_tli_create: could not bind: %s",
413 					    errorstr);
414 				goto freedata;
415 			}
416 			/*
417 			 * Should compare the addresses only if addr.len
418 			 * was non-zero
419 			 */
420 			if (bindaddr->addr.len &&
421 				(memcmp(bindaddr->addr.buf, tres->addr.buf,
422 					(int)tres->addr.len) != 0)) {
423 				(void) syslog(LOG_ERR,
424 		"svc_tli_create: could not bind to requested address: %s",
425 						"address mismatch");
426 				goto freedata;
427 			}
428 		} else {
429 			tres->qlen = 64; /* Chosen Arbitrarily */
430 			tres->addr.len = 0;
431 			if (t_bind(fd, tres, tres) == -1) {
432 				char errorstr[100];
433 
434 				__tli_sys_strerror(errorstr, sizeof (errorstr),
435 						t_errno, errno);
436 				(void) syslog(LOG_ERR,
437 					"svc_tli_create: could not bind: %s",
438 						errorstr);
439 				goto freedata;
440 			}
441 		}
442 
443 		/* Enable options of returning the ip's for udp */
444 		if (nconf) {
445 		    int ret = 0;
446 		    if (strcmp(nconf->nc_netid, "udp6") == 0) {
447 			ret = __rpc_tli_set_options(fd, IPPROTO_IPV6,
448 					IPV6_RECVPKTINFO, 1);
449 			if (ret < 0) {
450 			    char errorstr[100];
451 
452 			    __tli_sys_strerror(errorstr, sizeof (errorstr),
453 					t_errno, errno);
454 			    (void) syslog(LOG_ERR,
455 				"svc_tli_create: IPV6_RECVPKTINFO(2): %s",
456 					errorstr);
457 			    goto freedata;
458 			}
459 		    } else if (strcmp(nconf->nc_netid, "udp") == 0) {
460 			ret = __rpc_tli_set_options(fd, IPPROTO_IP,
461 					IP_RECVDSTADDR, 1);
462 			if (ret < 0) {
463 			    char errorstr[100];
464 
465 			    __tli_sys_strerror(errorstr, sizeof (errorstr),
466 					t_errno, errno);
467 			    (void) syslog(LOG_ERR,
468 				"svc_tli_create: IP_RECVDSTADDR(2): %s",
469 					errorstr);
470 			    goto freedata;
471 			}
472 		    }
473 		}
474 		break;
475 
476 	case T_IDLE:
477 		if (bindaddr) {
478 			/* Copy the entire stuff in tres */
479 			if (tres->addr.maxlen < bindaddr->addr.len) {
480 				(void) syslog(LOG_ERR,
481 				"svc_tli_create: illegal netbuf length");
482 				goto freedata;
483 			}
484 			tres->addr.len = bindaddr->addr.len;
485 			(void) memcpy(tres->addr.buf, bindaddr->addr.buf,
486 					(int)tres->addr.len);
487 		} else
488 			if (t_getname(fd, &(tres->addr), LOCALNAME) == -1)
489 				tres->addr.len = 0;
490 		break;
491 	case T_INREL:
492 		(void) t_rcvrel(fd);
493 		(void) t_sndrel(fd);
494 		(void) syslog(LOG_ERR,
495 			"svc_tli_create: other side wants to\
496 release connection");
497 		goto freedata;
498 
499 	case T_INCON:
500 		/* Do nothing here. Assume this is handled in rendezvous */
501 		break;
502 	case T_DATAXFER:
503 		/*
504 		 * This takes care of the case where a fd
505 		 * is passed on which a connection has already
506 		 * been accepted.
507 		 */
508 		if (t_getname(fd, &(tres->addr), LOCALNAME) == -1)
509 			tres->addr.len = 0;
510 		break;
511 	default:
512 		(void) syslog(LOG_ERR,
513 		    "svc_tli_create: connection in a wierd state (%d)", state);
514 		goto freedata;
515 	}
516 
517 	/*
518 	 * call transport specific function.
519 	 */
520 	switch (tinfo.servtype) {
521 		case T_COTS_ORD:
522 		case T_COTS:
523 			if (state == T_DATAXFER)
524 				xprt = svc_fd_create_private(fd, sendsz,
525 						recvsz);
526 			else
527 				xprt = svc_vc_create_private(fd, sendsz,
528 						recvsz);
529 			if (!nconf || !xprt)
530 				break;
531 			if ((tinfo.servtype == T_COTS_ORD) &&
532 				(state != T_DATAXFER) &&
533 				(strcmp(nconf->nc_protofmly, "inet") == 0))
534 				(void) __svc_vc_setflag(xprt, TRUE);
535 			break;
536 		case T_CLTS:
537 			xprt = svc_dg_create_private(fd, sendsz, recvsz);
538 			break;
539 		default:
540 			(void) syslog(LOG_ERR,
541 			    "svc_tli_create: bad service type");
542 			goto freedata;
543 	}
544 	if (xprt == NULL)
545 		/*
546 		 * The error messages here are spitted out by the lower layers:
547 		 * svc_vc_create(), svc_fd_create() and svc_dg_create().
548 		 */
549 		goto freedata;
550 
551 	/* fill in the other xprt information */
552 
553 	/* Assign the local bind address */
554 	xprt->xp_ltaddr = tres->addr;
555 	/* Fill in type of service */
556 	xprt->xp_type = tinfo.servtype;
557 	tres->addr.buf = NULL;
558 	(void) t_free((char *)tres, T_BIND);
559 	tres = NULL;
560 
561 	xprt->xp_rtaddr.len = 0;
562 	xprt->xp_rtaddr.maxlen = __rpc_get_a_size(tinfo.addr);
563 
564 	/* Allocate space for the remote bind info */
565 	if ((xprt->xp_rtaddr.buf = malloc(xprt->xp_rtaddr.maxlen)) == NULL) {
566 		(void) syslog(LOG_ERR, "svc_tli_create: No memory!");
567 		goto freedata;
568 	}
569 
570 	if (nconf) {
571 		xprt->xp_netid = strdup(nconf->nc_netid);
572 		if (xprt->xp_netid == NULL) {
573 			if (xprt->xp_rtaddr.buf)
574 				free(xprt->xp_rtaddr.buf);
575 			syslog(LOG_ERR, "svc_tli_create: strdup failed!");
576 			goto freedata;
577 		}
578 		xprt->xp_tp = strdup(nconf->nc_device);
579 		if (xprt->xp_tp == NULL) {
580 			if (xprt->xp_rtaddr.buf)
581 				free(xprt->xp_rtaddr.buf);
582 			if (xprt->xp_netid)
583 				free(xprt->xp_netid);
584 			syslog(LOG_ERR, "svc_tli_create: strdup failed!");
585 			goto freedata;
586 		}
587 	}
588 
589 /*
590  *	if (madefd && (tinfo.servtype == T_CLTS))
591  *		(void) ioctl(fd, I_POP, NULL);
592  */
593 	xprt_register(xprt);
594 	return (xprt);
595 
596 freedata:
597 	if (madefd)
598 		(void) t_close(fd);
599 	if (tres)
600 		(void) t_free((char *)tres, T_BIND);
601 	if (xprt) {
602 		if (!madefd) /* so that svc_destroy doesnt close fd */
603 			xprt->xp_fd = RPC_ANYFD;
604 		SVC_DESTROY(xprt);
605 	}
606 	return (NULL);
607 }
608