xref: /freebsd/sys/netinet/sctp_syscalls.c (revision 7fdf597e96a02165cfe22ff357b857d5fa15ed8a)
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 	struct filecaps fcaps;
145 	cap_rights_t rights;
146 	u_int fflag;
147 	int error, fd;
148 
149 	AUDIT_ARG_FD(uap->sd);
150 	error = getsock_cap(td, uap->sd,
151 	    cap_rights_init_one(&rights, CAP_PEELOFF), &headfp, &fcaps);
152 	if (error != 0)
153 		goto done2;
154 	fflag = atomic_load_int(&headfp->f_flag);
155 	head = headfp->f_data;
156 	if (head->so_proto->pr_protocol != IPPROTO_SCTP) {
157 		error = EOPNOTSUPP;
158 		goto done;
159 	}
160 	error = sctp_can_peel_off(head, (sctp_assoc_t)uap->name);
161 	if (error != 0)
162 		goto done;
163 	/*
164 	 * At this point we know we do have a assoc to pull
165 	 * we proceed to get the fd setup. This may block
166 	 * but that is ok.
167 	 */
168 
169 	error = falloc_caps(td, &nfp, &fd, 0, &fcaps);
170 	if (error != 0)
171 		goto done;
172 	td->td_retval[0] = fd;
173 
174 	CURVNET_SET(head->so_vnet);
175 	so = sopeeloff(head);
176 	if (so == NULL) {
177 		error = ENOMEM;
178 		goto noconnection;
179 	}
180 	finit(nfp, fflag, DTYPE_SOCKET, so, &socketops);
181 	error = sctp_do_peeloff(head, so, (sctp_assoc_t)uap->name);
182 	if (error != 0)
183 		goto noconnection;
184 	if (head->so_sigio != NULL)
185 		fsetown(fgetown(&head->so_sigio), &so->so_sigio);
186 
187 noconnection:
188 	/*
189 	 * close the new descriptor, assuming someone hasn't ripped it
190 	 * out from under us.
191 	 */
192 	if (error != 0)
193 		fdclose(td, nfp, fd);
194 
195 	/*
196 	 * Release explicitly held references before returning.
197 	 */
198 	CURVNET_RESTORE();
199 done:
200 	if (nfp != NULL)
201 		fdrop(nfp, td);
202 	fdrop(headfp, td);
203 done2:
204 	return (error);
205 }
206 
207 int
208 sys_sctp_generic_sendmsg(struct thread *td, struct sctp_generic_sendmsg_args *uap)
209 {
210 	struct sctp_sndrcvinfo sinfo, *u_sinfo = NULL;
211 	struct socket *so;
212 	struct file *fp = NULL;
213 	struct sockaddr *to = NULL;
214 #ifdef KTRACE
215 	struct uio *ktruio = NULL;
216 #endif
217 	struct uio auio;
218 	struct iovec iov[1];
219 	cap_rights_t rights;
220 	int error = 0, len;
221 
222 	if (uap->sinfo != NULL) {
223 		error = copyin(uap->sinfo, &sinfo, sizeof (sinfo));
224 		if (error != 0)
225 			return (error);
226 		u_sinfo = &sinfo;
227 	}
228 
229 	cap_rights_init_one(&rights, CAP_SEND);
230 	if (uap->tolen != 0) {
231 		error = getsockaddr(&to, uap->to, uap->tolen);
232 		if (error != 0) {
233 			to = NULL;
234 			goto sctp_bad2;
235 		}
236 		cap_rights_set_one(&rights, CAP_CONNECT);
237 	}
238 
239 	AUDIT_ARG_FD(uap->sd);
240 	error = getsock(td, uap->sd, &rights, &fp);
241 	if (error != 0)
242 		goto sctp_bad;
243 #ifdef KTRACE
244 	if (to && (KTRPOINT(td, KTR_STRUCT)))
245 		ktrsockaddr(to);
246 #endif
247 
248 	iov[0].iov_base = uap->msg;
249 	iov[0].iov_len = uap->mlen;
250 
251 	so = (struct socket *)fp->f_data;
252 	if (so->so_proto->pr_protocol != IPPROTO_SCTP) {
253 		error = EOPNOTSUPP;
254 		goto sctp_bad;
255 	}
256 #ifdef MAC
257 	error = mac_socket_check_send(td->td_ucred, so);
258 	if (error != 0)
259 		goto sctp_bad;
260 #endif /* MAC */
261 
262 	auio.uio_iov =  iov;
263 	auio.uio_iovcnt = 1;
264 	auio.uio_segflg = UIO_USERSPACE;
265 	auio.uio_rw = UIO_WRITE;
266 	auio.uio_td = td;
267 	auio.uio_offset = 0;			/* XXX */
268 	auio.uio_resid = 0;
269 #ifdef KTRACE
270 	if (KTRPOINT(td, KTR_GENIO))
271 		ktruio = cloneuio(&auio);
272 #endif /* KTRACE */
273 	len = auio.uio_resid = uap->mlen;
274 	CURVNET_SET(so->so_vnet);
275 	error = sctp_lower_sosend(so, to, &auio, (struct mbuf *)NULL,
276 	    (struct mbuf *)NULL, uap->flags, u_sinfo, td);
277 	CURVNET_RESTORE();
278 	if (error != 0) {
279 		if (auio.uio_resid != len && (error == ERESTART ||
280 		    error == EINTR || error == EWOULDBLOCK))
281 			error = 0;
282 		/* Generation of SIGPIPE can be controlled per socket. */
283 		if (error == EPIPE && !(so->so_options & SO_NOSIGPIPE) &&
284 		    !(uap->flags & MSG_NOSIGNAL)) {
285 			PROC_LOCK(td->td_proc);
286 			tdsignal(td, SIGPIPE);
287 			PROC_UNLOCK(td->td_proc);
288 		}
289 	}
290 	if (error == 0)
291 		td->td_retval[0] = len - auio.uio_resid;
292 #ifdef KTRACE
293 	if (ktruio != NULL) {
294 		if (error == 0)
295 			ktruio->uio_resid = td->td_retval[0];
296 		ktrgenio(uap->sd, UIO_WRITE, ktruio, error);
297 	}
298 #endif /* KTRACE */
299 sctp_bad:
300 	if (fp != NULL)
301 		fdrop(fp, td);
302 sctp_bad2:
303 	free(to, M_SONAME);
304 	return (error);
305 }
306 
307 int
308 sys_sctp_generic_sendmsg_iov(struct thread *td, struct sctp_generic_sendmsg_iov_args *uap)
309 {
310 	struct sctp_sndrcvinfo sinfo, *u_sinfo = NULL;
311 	struct socket *so;
312 	struct file *fp = NULL;
313 	struct sockaddr *to = NULL;
314 #ifdef KTRACE
315 	struct uio *ktruio = NULL;
316 #endif
317 	struct uio auio;
318 	struct iovec *iov, *tiov;
319 	cap_rights_t rights;
320 	ssize_t len;
321 	int error, i;
322 
323 	if (uap->sinfo != NULL) {
324 		error = copyin(uap->sinfo, &sinfo, sizeof (sinfo));
325 		if (error != 0)
326 			return (error);
327 		u_sinfo = &sinfo;
328 	}
329 	cap_rights_init_one(&rights, CAP_SEND);
330 	if (uap->tolen != 0) {
331 		error = getsockaddr(&to, uap->to, uap->tolen);
332 		if (error != 0) {
333 			to = NULL;
334 			goto sctp_bad2;
335 		}
336 		cap_rights_set_one(&rights, CAP_CONNECT);
337 	}
338 
339 	AUDIT_ARG_FD(uap->sd);
340 	error = getsock(td, uap->sd, &rights, &fp);
341 	if (error != 0)
342 		goto sctp_bad1;
343 
344 #ifdef COMPAT_FREEBSD32
345 	if (SV_CURPROC_FLAG(SV_ILP32))
346 		error = freebsd32_copyiniov((struct iovec32 *)uap->iov,
347 		    uap->iovlen, &iov, EMSGSIZE);
348 	else
349 #endif
350 		error = copyiniov(uap->iov, uap->iovlen, &iov, EMSGSIZE);
351 	if (error != 0)
352 		goto sctp_bad1;
353 #ifdef KTRACE
354 	if (to && (KTRPOINT(td, KTR_STRUCT)))
355 		ktrsockaddr(to);
356 #endif
357 
358 	so = (struct socket *)fp->f_data;
359 	if (so->so_proto->pr_protocol != IPPROTO_SCTP) {
360 		error = EOPNOTSUPP;
361 		goto sctp_bad;
362 	}
363 #ifdef MAC
364 	error = mac_socket_check_send(td->td_ucred, so);
365 	if (error != 0)
366 		goto sctp_bad;
367 #endif /* MAC */
368 
369 	auio.uio_iov = iov;
370 	auio.uio_iovcnt = uap->iovlen;
371 	auio.uio_segflg = UIO_USERSPACE;
372 	auio.uio_rw = UIO_WRITE;
373 	auio.uio_td = td;
374 	auio.uio_offset = 0;			/* XXX */
375 	auio.uio_resid = 0;
376 	tiov = iov;
377 	for (i = 0; i <uap->iovlen; i++, tiov++) {
378 		if ((auio.uio_resid += tiov->iov_len) < 0) {
379 			error = EINVAL;
380 			goto sctp_bad;
381 		}
382 	}
383 #ifdef KTRACE
384 	if (KTRPOINT(td, KTR_GENIO))
385 		ktruio = cloneuio(&auio);
386 #endif /* KTRACE */
387 	len = auio.uio_resid;
388 	CURVNET_SET(so->so_vnet);
389 	error = sctp_lower_sosend(so, to, &auio,
390 		    (struct mbuf *)NULL, (struct mbuf *)NULL,
391 		    uap->flags, u_sinfo, td);
392 	CURVNET_RESTORE();
393 	if (error != 0) {
394 		if (auio.uio_resid != len && (error == ERESTART ||
395 		    error == EINTR || error == EWOULDBLOCK))
396 			error = 0;
397 		/* Generation of SIGPIPE can be controlled per socket */
398 		if (error == EPIPE && !(so->so_options & SO_NOSIGPIPE) &&
399 		    !(uap->flags & MSG_NOSIGNAL)) {
400 			PROC_LOCK(td->td_proc);
401 			tdsignal(td, SIGPIPE);
402 			PROC_UNLOCK(td->td_proc);
403 		}
404 	}
405 	if (error == 0)
406 		td->td_retval[0] = len - auio.uio_resid;
407 #ifdef KTRACE
408 	if (ktruio != NULL) {
409 		if (error == 0)
410 			ktruio->uio_resid = td->td_retval[0];
411 		ktrgenio(uap->sd, UIO_WRITE, ktruio, error);
412 	}
413 #endif /* KTRACE */
414 sctp_bad:
415 	free(iov, M_IOV);
416 sctp_bad1:
417 	if (fp != NULL)
418 		fdrop(fp, td);
419 sctp_bad2:
420 	free(to, M_SONAME);
421 	return (error);
422 }
423 
424 int
425 sys_sctp_generic_recvmsg(struct thread *td, struct sctp_generic_recvmsg_args *uap)
426 {
427 	uint8_t sockbufstore[256];
428 	struct uio auio;
429 	struct iovec *iov, *tiov;
430 	struct sctp_sndrcvinfo sinfo;
431 	struct socket *so;
432 	struct file *fp = NULL;
433 	struct sockaddr *fromsa;
434 	cap_rights_t rights;
435 #ifdef KTRACE
436 	struct uio *ktruio = NULL;
437 #endif
438 	ssize_t len;
439 	int error, fromlen, i, msg_flags;
440 
441 	AUDIT_ARG_FD(uap->sd);
442 	error = getsock(td, uap->sd, cap_rights_init_one(&rights, CAP_RECV),
443 	    &fp);
444 	if (error != 0)
445 		return (error);
446 #ifdef COMPAT_FREEBSD32
447 	if (SV_CURPROC_FLAG(SV_ILP32))
448 		error = freebsd32_copyiniov((struct iovec32 *)uap->iov,
449 		    uap->iovlen, &iov, EMSGSIZE);
450 	else
451 #endif
452 		error = copyiniov(uap->iov, uap->iovlen, &iov, EMSGSIZE);
453 	if (error != 0)
454 		goto out1;
455 
456 	so = fp->f_data;
457 	if (so->so_proto->pr_protocol != IPPROTO_SCTP) {
458 		error = EOPNOTSUPP;
459 		goto out;
460 	}
461 #ifdef MAC
462 	error = mac_socket_check_receive(td->td_ucred, so);
463 	if (error != 0)
464 		goto out;
465 #endif /* MAC */
466 
467 	if (uap->fromlenaddr != NULL) {
468 		error = copyin(uap->fromlenaddr, &fromlen, sizeof (fromlen));
469 		if (error != 0)
470 			goto out;
471 	} else {
472 		fromlen = 0;
473 	}
474 	if (uap->msg_flags) {
475 		error = copyin(uap->msg_flags, &msg_flags, sizeof (int));
476 		if (error != 0)
477 			goto out;
478 	} else {
479 		msg_flags = 0;
480 	}
481 	auio.uio_iov = iov;
482 	auio.uio_iovcnt = uap->iovlen;
483 	auio.uio_segflg = UIO_USERSPACE;
484 	auio.uio_rw = UIO_READ;
485 	auio.uio_td = td;
486 	auio.uio_offset = 0;			/* XXX */
487 	auio.uio_resid = 0;
488 	tiov = iov;
489 	for (i = 0; i <uap->iovlen; i++, tiov++) {
490 		if ((auio.uio_resid += tiov->iov_len) < 0) {
491 			error = EINVAL;
492 			goto out;
493 		}
494 	}
495 	len = auio.uio_resid;
496 	fromsa = (struct sockaddr *)sockbufstore;
497 
498 #ifdef KTRACE
499 	if (KTRPOINT(td, KTR_GENIO))
500 		ktruio = cloneuio(&auio);
501 #endif /* KTRACE */
502 	memset(&sinfo, 0, sizeof(struct sctp_sndrcvinfo));
503 	CURVNET_SET(so->so_vnet);
504 	error = sctp_sorecvmsg(so, &auio, (struct mbuf **)NULL,
505 		    fromsa, fromlen, &msg_flags,
506 		    (struct sctp_sndrcvinfo *)&sinfo, 1);
507 	CURVNET_RESTORE();
508 	if (error != 0) {
509 		if (auio.uio_resid != len && (error == ERESTART ||
510 		    error == EINTR || error == EWOULDBLOCK))
511 			error = 0;
512 	} else {
513 		if (uap->sinfo)
514 			error = copyout(&sinfo, uap->sinfo, sizeof (sinfo));
515 	}
516 #ifdef KTRACE
517 	if (ktruio != NULL) {
518 		ktruio->uio_resid = len - auio.uio_resid;
519 		ktrgenio(uap->sd, UIO_READ, ktruio, error);
520 	}
521 #endif /* KTRACE */
522 	if (error != 0)
523 		goto out;
524 	td->td_retval[0] = len - auio.uio_resid;
525 
526 	if (fromlen && uap->from) {
527 		len = fromlen;
528 		if (len <= 0 || fromsa == NULL)
529 			len = 0;
530 		else {
531 			len = MIN(len, fromsa->sa_len);
532 			error = copyout(fromsa, uap->from, (size_t)len);
533 			if (error != 0)
534 				goto out;
535 		}
536 		error = copyout(&len, uap->fromlenaddr, sizeof (socklen_t));
537 		if (error != 0)
538 			goto out;
539 	}
540 #ifdef KTRACE
541 	if (KTRPOINT(td, KTR_STRUCT))
542 		ktrsockaddr(fromsa);
543 #endif
544 	if (uap->msg_flags) {
545 		error = copyout(&msg_flags, uap->msg_flags, sizeof (int));
546 		if (error != 0)
547 			goto out;
548 	}
549 out:
550 	free(iov, M_IOV);
551 out1:
552 	if (fp != NULL)
553 		fdrop(fp, td);
554 
555 	return (error);
556 }
557