xref: /freebsd/sys/netinet/sctp_syscalls.c (revision f126890ac5386406dadf7c4cfa9566cbb56537c5)
1 /*-
2  * Copyright (c) 1982, 1986, 1989, 1990, 1993
3  *	The Regents of the University of California.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  * 3. Neither the name of the University nor the names of its contributors
14  *    may be used to endorse or promote products derived from this software
15  *    without specific prior written permission.
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE REGENTS 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 REGENTS 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 #include <sys/cdefs.h>
32 #include "opt_capsicum.h"
33 #include "opt_sctp.h"
34 #include "opt_ktrace.h"
35 
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/capsicum.h>
39 #include <sys/kernel.h>
40 #include <sys/lock.h>
41 #include <sys/mutex.h>
42 #include <sys/sysproto.h>
43 #include <sys/malloc.h>
44 #include <sys/filedesc.h>
45 #include <sys/event.h>
46 #include <sys/proc.h>
47 #include <sys/fcntl.h>
48 #include <sys/file.h>
49 #include <sys/filio.h>
50 #include <sys/jail.h>
51 #include <sys/mount.h>
52 #include <sys/mbuf.h>
53 #include <sys/protosw.h>
54 #include <sys/sf_buf.h>
55 #include <sys/sysent.h>
56 #include <sys/socket.h>
57 #include <sys/socketvar.h>
58 #include <sys/signalvar.h>
59 #include <sys/syscall.h>
60 #include <sys/syscallsubr.h>
61 #include <sys/sysctl.h>
62 #include <sys/uio.h>
63 #include <sys/vnode.h>
64 #ifdef KTRACE
65 #include <sys/ktrace.h>
66 #endif
67 #ifdef COMPAT_FREEBSD32
68 #include <compat/freebsd32/freebsd32.h>
69 #include <compat/freebsd32/freebsd32_syscall.h>
70 #include <compat/freebsd32/freebsd32_util.h>
71 #endif
72 
73 #include <net/vnet.h>
74 
75 #include <security/audit/audit.h>
76 #include <security/mac/mac_framework.h>
77 
78 #include <netinet/sctp.h>
79 #include <netinet/sctp_os_bsd.h>
80 #include <netinet/sctp_peeloff.h>
81 
82 static struct syscall_helper_data sctp_syscalls[] = {
83 	SYSCALL_INIT_HELPER_F(sctp_peeloff, SYF_CAPENABLED),
84 	SYSCALL_INIT_HELPER_F(sctp_generic_sendmsg, SYF_CAPENABLED),
85 	SYSCALL_INIT_HELPER_F(sctp_generic_sendmsg_iov, SYF_CAPENABLED),
86 	SYSCALL_INIT_HELPER_F(sctp_generic_recvmsg, SYF_CAPENABLED),
87 	SYSCALL_INIT_LAST
88 };
89 
90 #ifdef COMPAT_FREEBSD32
91 static struct syscall_helper_data sctp32_syscalls[] = {
92 	SYSCALL32_INIT_HELPER_COMPAT(sctp_peeloff),
93 	SYSCALL32_INIT_HELPER_COMPAT(sctp_generic_sendmsg),
94 	SYSCALL32_INIT_HELPER_COMPAT(sctp_generic_sendmsg_iov),
95 	SYSCALL32_INIT_HELPER_COMPAT(sctp_generic_recvmsg),
96 	SYSCALL_INIT_LAST
97 };
98 #endif
99 
100 int
101 sctp_syscalls_init(void)
102 {
103 	int error;
104 
105 	error = syscall_helper_register(sctp_syscalls, SY_THR_STATIC_KLD);
106 	if (error != 0)
107 		return (error);
108 #ifdef COMPAT_FREEBSD32
109 	error = syscall32_helper_register(sctp32_syscalls, SY_THR_STATIC_KLD);
110 	if (error != 0)
111 		return (error);
112 #endif
113 	return (0);
114 }
115 
116 #ifdef SCTP
117 SYSINIT(sctp_syscalls, SI_SUB_SYSCALLS, SI_ORDER_ANY, sctp_syscalls_init, NULL);
118 #endif
119 
120 int
121 sctp_syscalls_uninit(void)
122 {
123 	int error;
124 
125 #ifdef COMPAT_FREEBSD32
126 	error = syscall32_helper_unregister(sctp32_syscalls);
127 	if (error != 0)
128 		return (error);
129 #endif
130 	error = syscall_helper_unregister(sctp_syscalls);
131 	if (error != 0)
132 		return (error);
133 	return (0);
134 }
135 
136 /*
137  * SCTP syscalls.
138  */
139 int
140 sys_sctp_peeloff(struct thread *td, struct sctp_peeloff_args *uap)
141 {
142 	struct file *headfp, *nfp = NULL;
143 	struct socket *head, *so;
144 	cap_rights_t rights;
145 	u_int fflag;
146 	int error, fd;
147 
148 	AUDIT_ARG_FD(uap->sd);
149 	error = getsock(td, uap->sd, cap_rights_init_one(&rights, CAP_PEELOFF),
150 	    &headfp);
151 	if (error != 0)
152 		goto done2;
153 	fflag = atomic_load_int(&headfp->f_flag);
154 	head = headfp->f_data;
155 	if (head->so_proto->pr_protocol != IPPROTO_SCTP) {
156 		error = EOPNOTSUPP;
157 		goto done;
158 	}
159 	error = sctp_can_peel_off(head, (sctp_assoc_t)uap->name);
160 	if (error != 0)
161 		goto done;
162 	/*
163 	 * At this point we know we do have a assoc to pull
164 	 * we proceed to get the fd setup. This may block
165 	 * but that is ok.
166 	 */
167 
168 	error = falloc(td, &nfp, &fd, 0);
169 	if (error != 0)
170 		goto done;
171 	td->td_retval[0] = fd;
172 
173 	CURVNET_SET(head->so_vnet);
174 	so = sopeeloff(head);
175 	if (so == NULL) {
176 		error = ENOMEM;
177 		goto noconnection;
178 	}
179 	finit(nfp, fflag, DTYPE_SOCKET, so, &socketops);
180 	error = sctp_do_peeloff(head, so, (sctp_assoc_t)uap->name);
181 	if (error != 0)
182 		goto noconnection;
183 	if (head->so_sigio != NULL)
184 		fsetown(fgetown(&head->so_sigio), &so->so_sigio);
185 
186 noconnection:
187 	/*
188 	 * close the new descriptor, assuming someone hasn't ripped it
189 	 * out from under us.
190 	 */
191 	if (error != 0)
192 		fdclose(td, nfp, fd);
193 
194 	/*
195 	 * Release explicitly held references before returning.
196 	 */
197 	CURVNET_RESTORE();
198 done:
199 	if (nfp != NULL)
200 		fdrop(nfp, td);
201 	fdrop(headfp, td);
202 done2:
203 	return (error);
204 }
205 
206 int
207 sys_sctp_generic_sendmsg(struct thread *td, struct sctp_generic_sendmsg_args *uap)
208 {
209 	struct sctp_sndrcvinfo sinfo, *u_sinfo = NULL;
210 	struct socket *so;
211 	struct file *fp = NULL;
212 	struct sockaddr *to = NULL;
213 #ifdef KTRACE
214 	struct uio *ktruio = NULL;
215 #endif
216 	struct uio auio;
217 	struct iovec iov[1];
218 	cap_rights_t rights;
219 	int error = 0, len;
220 
221 	if (uap->sinfo != NULL) {
222 		error = copyin(uap->sinfo, &sinfo, sizeof (sinfo));
223 		if (error != 0)
224 			return (error);
225 		u_sinfo = &sinfo;
226 	}
227 
228 	cap_rights_init_one(&rights, CAP_SEND);
229 	if (uap->tolen != 0) {
230 		error = getsockaddr(&to, uap->to, uap->tolen);
231 		if (error != 0) {
232 			to = NULL;
233 			goto sctp_bad2;
234 		}
235 		cap_rights_set_one(&rights, CAP_CONNECT);
236 	}
237 
238 	AUDIT_ARG_FD(uap->sd);
239 	error = getsock(td, uap->sd, &rights, &fp);
240 	if (error != 0)
241 		goto sctp_bad;
242 #ifdef KTRACE
243 	if (to && (KTRPOINT(td, KTR_STRUCT)))
244 		ktrsockaddr(to);
245 #endif
246 
247 	iov[0].iov_base = uap->msg;
248 	iov[0].iov_len = uap->mlen;
249 
250 	so = (struct socket *)fp->f_data;
251 	if (so->so_proto->pr_protocol != IPPROTO_SCTP) {
252 		error = EOPNOTSUPP;
253 		goto sctp_bad;
254 	}
255 #ifdef MAC
256 	error = mac_socket_check_send(td->td_ucred, so);
257 	if (error != 0)
258 		goto sctp_bad;
259 #endif /* MAC */
260 
261 	auio.uio_iov =  iov;
262 	auio.uio_iovcnt = 1;
263 	auio.uio_segflg = UIO_USERSPACE;
264 	auio.uio_rw = UIO_WRITE;
265 	auio.uio_td = td;
266 	auio.uio_offset = 0;			/* XXX */
267 	auio.uio_resid = 0;
268 #ifdef KTRACE
269 	if (KTRPOINT(td, KTR_GENIO))
270 		ktruio = cloneuio(&auio);
271 #endif /* KTRACE */
272 	len = auio.uio_resid = uap->mlen;
273 	CURVNET_SET(so->so_vnet);
274 	error = sctp_lower_sosend(so, to, &auio, (struct mbuf *)NULL,
275 	    (struct mbuf *)NULL, uap->flags, u_sinfo, td);
276 	CURVNET_RESTORE();
277 	if (error != 0) {
278 		if (auio.uio_resid != len && (error == ERESTART ||
279 		    error == EINTR || error == EWOULDBLOCK))
280 			error = 0;
281 		/* Generation of SIGPIPE can be controlled per socket. */
282 		if (error == EPIPE && !(so->so_options & SO_NOSIGPIPE) &&
283 		    !(uap->flags & MSG_NOSIGNAL)) {
284 			PROC_LOCK(td->td_proc);
285 			tdsignal(td, SIGPIPE);
286 			PROC_UNLOCK(td->td_proc);
287 		}
288 	}
289 	if (error == 0)
290 		td->td_retval[0] = len - auio.uio_resid;
291 #ifdef KTRACE
292 	if (ktruio != NULL) {
293 		if (error == 0)
294 			ktruio->uio_resid = td->td_retval[0];
295 		ktrgenio(uap->sd, UIO_WRITE, ktruio, error);
296 	}
297 #endif /* KTRACE */
298 sctp_bad:
299 	if (fp != NULL)
300 		fdrop(fp, td);
301 sctp_bad2:
302 	free(to, M_SONAME);
303 	return (error);
304 }
305 
306 int
307 sys_sctp_generic_sendmsg_iov(struct thread *td, struct sctp_generic_sendmsg_iov_args *uap)
308 {
309 	struct sctp_sndrcvinfo sinfo, *u_sinfo = NULL;
310 	struct socket *so;
311 	struct file *fp = NULL;
312 	struct sockaddr *to = NULL;
313 #ifdef KTRACE
314 	struct uio *ktruio = NULL;
315 #endif
316 	struct uio auio;
317 	struct iovec *iov, *tiov;
318 	cap_rights_t rights;
319 	ssize_t len;
320 	int error, i;
321 
322 	if (uap->sinfo != NULL) {
323 		error = copyin(uap->sinfo, &sinfo, sizeof (sinfo));
324 		if (error != 0)
325 			return (error);
326 		u_sinfo = &sinfo;
327 	}
328 	cap_rights_init_one(&rights, CAP_SEND);
329 	if (uap->tolen != 0) {
330 		error = getsockaddr(&to, uap->to, uap->tolen);
331 		if (error != 0) {
332 			to = NULL;
333 			goto sctp_bad2;
334 		}
335 		cap_rights_set_one(&rights, CAP_CONNECT);
336 	}
337 
338 	AUDIT_ARG_FD(uap->sd);
339 	error = getsock(td, uap->sd, &rights, &fp);
340 	if (error != 0)
341 		goto sctp_bad1;
342 
343 #ifdef COMPAT_FREEBSD32
344 	if (SV_CURPROC_FLAG(SV_ILP32))
345 		error = freebsd32_copyiniov((struct iovec32 *)uap->iov,
346 		    uap->iovlen, &iov, EMSGSIZE);
347 	else
348 #endif
349 		error = copyiniov(uap->iov, uap->iovlen, &iov, EMSGSIZE);
350 	if (error != 0)
351 		goto sctp_bad1;
352 #ifdef KTRACE
353 	if (to && (KTRPOINT(td, KTR_STRUCT)))
354 		ktrsockaddr(to);
355 #endif
356 
357 	so = (struct socket *)fp->f_data;
358 	if (so->so_proto->pr_protocol != IPPROTO_SCTP) {
359 		error = EOPNOTSUPP;
360 		goto sctp_bad;
361 	}
362 #ifdef MAC
363 	error = mac_socket_check_send(td->td_ucred, so);
364 	if (error != 0)
365 		goto sctp_bad;
366 #endif /* MAC */
367 
368 	auio.uio_iov = iov;
369 	auio.uio_iovcnt = uap->iovlen;
370 	auio.uio_segflg = UIO_USERSPACE;
371 	auio.uio_rw = UIO_WRITE;
372 	auio.uio_td = td;
373 	auio.uio_offset = 0;			/* XXX */
374 	auio.uio_resid = 0;
375 	tiov = iov;
376 	for (i = 0; i <uap->iovlen; i++, tiov++) {
377 		if ((auio.uio_resid += tiov->iov_len) < 0) {
378 			error = EINVAL;
379 			goto sctp_bad;
380 		}
381 	}
382 #ifdef KTRACE
383 	if (KTRPOINT(td, KTR_GENIO))
384 		ktruio = cloneuio(&auio);
385 #endif /* KTRACE */
386 	len = auio.uio_resid;
387 	CURVNET_SET(so->so_vnet);
388 	error = sctp_lower_sosend(so, to, &auio,
389 		    (struct mbuf *)NULL, (struct mbuf *)NULL,
390 		    uap->flags, u_sinfo, td);
391 	CURVNET_RESTORE();
392 	if (error != 0) {
393 		if (auio.uio_resid != len && (error == ERESTART ||
394 		    error == EINTR || error == EWOULDBLOCK))
395 			error = 0;
396 		/* Generation of SIGPIPE can be controlled per socket */
397 		if (error == EPIPE && !(so->so_options & SO_NOSIGPIPE) &&
398 		    !(uap->flags & MSG_NOSIGNAL)) {
399 			PROC_LOCK(td->td_proc);
400 			tdsignal(td, SIGPIPE);
401 			PROC_UNLOCK(td->td_proc);
402 		}
403 	}
404 	if (error == 0)
405 		td->td_retval[0] = len - auio.uio_resid;
406 #ifdef KTRACE
407 	if (ktruio != NULL) {
408 		if (error == 0)
409 			ktruio->uio_resid = td->td_retval[0];
410 		ktrgenio(uap->sd, UIO_WRITE, ktruio, error);
411 	}
412 #endif /* KTRACE */
413 sctp_bad:
414 	free(iov, M_IOV);
415 sctp_bad1:
416 	if (fp != NULL)
417 		fdrop(fp, td);
418 sctp_bad2:
419 	free(to, M_SONAME);
420 	return (error);
421 }
422 
423 int
424 sys_sctp_generic_recvmsg(struct thread *td, struct sctp_generic_recvmsg_args *uap)
425 {
426 	uint8_t sockbufstore[256];
427 	struct uio auio;
428 	struct iovec *iov, *tiov;
429 	struct sctp_sndrcvinfo sinfo;
430 	struct socket *so;
431 	struct file *fp = NULL;
432 	struct sockaddr *fromsa;
433 	cap_rights_t rights;
434 #ifdef KTRACE
435 	struct uio *ktruio = NULL;
436 #endif
437 	ssize_t len;
438 	int error, fromlen, i, msg_flags;
439 
440 	AUDIT_ARG_FD(uap->sd);
441 	error = getsock(td, uap->sd, cap_rights_init_one(&rights, CAP_RECV),
442 	    &fp);
443 	if (error != 0)
444 		return (error);
445 #ifdef COMPAT_FREEBSD32
446 	if (SV_CURPROC_FLAG(SV_ILP32))
447 		error = freebsd32_copyiniov((struct iovec32 *)uap->iov,
448 		    uap->iovlen, &iov, EMSGSIZE);
449 	else
450 #endif
451 		error = copyiniov(uap->iov, uap->iovlen, &iov, EMSGSIZE);
452 	if (error != 0)
453 		goto out1;
454 
455 	so = fp->f_data;
456 	if (so->so_proto->pr_protocol != IPPROTO_SCTP) {
457 		error = EOPNOTSUPP;
458 		goto out;
459 	}
460 #ifdef MAC
461 	error = mac_socket_check_receive(td->td_ucred, so);
462 	if (error != 0)
463 		goto out;
464 #endif /* MAC */
465 
466 	if (uap->fromlenaddr != NULL) {
467 		error = copyin(uap->fromlenaddr, &fromlen, sizeof (fromlen));
468 		if (error != 0)
469 			goto out;
470 	} else {
471 		fromlen = 0;
472 	}
473 	if (uap->msg_flags) {
474 		error = copyin(uap->msg_flags, &msg_flags, sizeof (int));
475 		if (error != 0)
476 			goto out;
477 	} else {
478 		msg_flags = 0;
479 	}
480 	auio.uio_iov = iov;
481 	auio.uio_iovcnt = uap->iovlen;
482 	auio.uio_segflg = UIO_USERSPACE;
483 	auio.uio_rw = UIO_READ;
484 	auio.uio_td = td;
485 	auio.uio_offset = 0;			/* XXX */
486 	auio.uio_resid = 0;
487 	tiov = iov;
488 	for (i = 0; i <uap->iovlen; i++, tiov++) {
489 		if ((auio.uio_resid += tiov->iov_len) < 0) {
490 			error = EINVAL;
491 			goto out;
492 		}
493 	}
494 	len = auio.uio_resid;
495 	fromsa = (struct sockaddr *)sockbufstore;
496 
497 #ifdef KTRACE
498 	if (KTRPOINT(td, KTR_GENIO))
499 		ktruio = cloneuio(&auio);
500 #endif /* KTRACE */
501 	memset(&sinfo, 0, sizeof(struct sctp_sndrcvinfo));
502 	CURVNET_SET(so->so_vnet);
503 	error = sctp_sorecvmsg(so, &auio, (struct mbuf **)NULL,
504 		    fromsa, fromlen, &msg_flags,
505 		    (struct sctp_sndrcvinfo *)&sinfo, 1);
506 	CURVNET_RESTORE();
507 	if (error != 0) {
508 		if (auio.uio_resid != len && (error == ERESTART ||
509 		    error == EINTR || error == EWOULDBLOCK))
510 			error = 0;
511 	} else {
512 		if (uap->sinfo)
513 			error = copyout(&sinfo, uap->sinfo, sizeof (sinfo));
514 	}
515 #ifdef KTRACE
516 	if (ktruio != NULL) {
517 		ktruio->uio_resid = len - auio.uio_resid;
518 		ktrgenio(uap->sd, UIO_READ, ktruio, error);
519 	}
520 #endif /* KTRACE */
521 	if (error != 0)
522 		goto out;
523 	td->td_retval[0] = len - auio.uio_resid;
524 
525 	if (fromlen && uap->from) {
526 		len = fromlen;
527 		if (len <= 0 || fromsa == NULL)
528 			len = 0;
529 		else {
530 			len = MIN(len, fromsa->sa_len);
531 			error = copyout(fromsa, uap->from, (size_t)len);
532 			if (error != 0)
533 				goto out;
534 		}
535 		error = copyout(&len, uap->fromlenaddr, sizeof (socklen_t));
536 		if (error != 0)
537 			goto out;
538 	}
539 #ifdef KTRACE
540 	if (KTRPOINT(td, KTR_STRUCT))
541 		ktrsockaddr(fromsa);
542 #endif
543 	if (uap->msg_flags) {
544 		error = copyout(&msg_flags, uap->msg_flags, sizeof (int));
545 		if (error != 0)
546 			goto out;
547 	}
548 out:
549 	free(iov, M_IOV);
550 out1:
551 	if (fp != NULL)
552 		fdrop(fp, td);
553 
554 	return (error);
555 }
556