xref: /freebsd/sys/compat/linux/linux_socket.c (revision f10845877e962a7dcdc4cf9b9614bdfcdac46d59)
1 /*-
2  * SPDX-License-Identifier: BSD-2-Clause-FreeBSD
3  *
4  * Copyright (c) 1995 Søren Schmidt
5  * All rights reserved.
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  * 1. Redistributions of source code must retain the above copyright
11  *    notice, this list of conditions and the following disclaimer.
12  * 2. Redistributions in binary form must reproduce the above copyright
13  *    notice, this list of conditions and the following disclaimer in the
14  *    documentation and/or other materials provided with the distribution.
15  *
16  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26  * SUCH DAMAGE.
27  */
28 
29 #include <sys/cdefs.h>
30 __FBSDID("$FreeBSD$");
31 
32 /* XXX we use functions that might not exist. */
33 #include "opt_compat.h"
34 #include "opt_inet6.h"
35 
36 #include <sys/param.h>
37 #include <sys/proc.h>
38 #include <sys/systm.h>
39 #include <sys/sysproto.h>
40 #include <sys/capsicum.h>
41 #include <sys/fcntl.h>
42 #include <sys/file.h>
43 #include <sys/filedesc.h>
44 #include <sys/limits.h>
45 #include <sys/lock.h>
46 #include <sys/malloc.h>
47 #include <sys/mutex.h>
48 #include <sys/mbuf.h>
49 #include <sys/socket.h>
50 #include <sys/socketvar.h>
51 #include <sys/syscallsubr.h>
52 #include <sys/uio.h>
53 #include <sys/stat.h>
54 #include <sys/syslog.h>
55 #include <sys/un.h>
56 #include <sys/unistd.h>
57 
58 #include <security/audit/audit.h>
59 
60 #include <net/if.h>
61 #include <net/vnet.h>
62 #include <netinet/in.h>
63 #include <netinet/in_systm.h>
64 #include <netinet/ip.h>
65 #include <netinet/tcp.h>
66 #ifdef INET6
67 #include <netinet/ip6.h>
68 #include <netinet6/ip6_var.h>
69 #endif
70 
71 #ifdef COMPAT_LINUX32
72 #include <machine/../linux32/linux.h>
73 #include <machine/../linux32/linux32_proto.h>
74 #else
75 #include <machine/../linux/linux.h>
76 #include <machine/../linux/linux_proto.h>
77 #endif
78 #include <compat/linux/linux_common.h>
79 #include <compat/linux/linux_file.h>
80 #include <compat/linux/linux_mib.h>
81 #include <compat/linux/linux_socket.h>
82 #include <compat/linux/linux_timer.h>
83 #include <compat/linux/linux_util.h>
84 
85 static int linux_sendmsg_common(struct thread *, l_int, struct l_msghdr *,
86 					l_uint);
87 static int linux_recvmsg_common(struct thread *, l_int, struct l_msghdr *,
88 					l_uint, struct msghdr *);
89 static int linux_set_socket_flags(int, int *);
90 
91 static int
92 linux_to_bsd_sockopt_level(int level)
93 {
94 
95 	if (level == LINUX_SOL_SOCKET)
96 		return (SOL_SOCKET);
97 	/* Remaining values are RFC-defined protocol numbers. */
98 	return (level);
99 }
100 
101 static int
102 bsd_to_linux_sockopt_level(int level)
103 {
104 
105 	if (level == SOL_SOCKET)
106 		return (LINUX_SOL_SOCKET);
107 	return (level);
108 }
109 
110 static int
111 linux_to_bsd_ip_sockopt(int opt)
112 {
113 
114 	switch (opt) {
115 	case LINUX_IP_TOS:
116 		return (IP_TOS);
117 	case LINUX_IP_TTL:
118 		return (IP_TTL);
119 	case LINUX_IP_OPTIONS:
120 		return (IP_OPTIONS);
121 	case LINUX_IP_MULTICAST_IF:
122 		return (IP_MULTICAST_IF);
123 	case LINUX_IP_MULTICAST_TTL:
124 		return (IP_MULTICAST_TTL);
125 	case LINUX_IP_MULTICAST_LOOP:
126 		return (IP_MULTICAST_LOOP);
127 	case LINUX_IP_ADD_MEMBERSHIP:
128 		return (IP_ADD_MEMBERSHIP);
129 	case LINUX_IP_DROP_MEMBERSHIP:
130 		return (IP_DROP_MEMBERSHIP);
131 	case LINUX_IP_HDRINCL:
132 		return (IP_HDRINCL);
133 	}
134 	return (-1);
135 }
136 
137 static int
138 linux_to_bsd_ip6_sockopt(int opt)
139 {
140 
141 	switch (opt) {
142 	case LINUX_IPV6_NEXTHOP:
143 		return (IPV6_NEXTHOP);
144 	case LINUX_IPV6_UNICAST_HOPS:
145 		return (IPV6_UNICAST_HOPS);
146 	case LINUX_IPV6_MULTICAST_IF:
147 		return (IPV6_MULTICAST_IF);
148 	case LINUX_IPV6_MULTICAST_HOPS:
149 		return (IPV6_MULTICAST_HOPS);
150 	case LINUX_IPV6_MULTICAST_LOOP:
151 		return (IPV6_MULTICAST_LOOP);
152 	case LINUX_IPV6_ADD_MEMBERSHIP:
153 		return (IPV6_JOIN_GROUP);
154 	case LINUX_IPV6_DROP_MEMBERSHIP:
155 		return (IPV6_LEAVE_GROUP);
156 	case LINUX_IPV6_V6ONLY:
157 		return (IPV6_V6ONLY);
158 	case LINUX_IPV6_DONTFRAG:
159 		return (IPV6_DONTFRAG);
160 #if 0
161 	case LINUX_IPV6_CHECKSUM:
162 		return (IPV6_CHECKSUM);
163 	case LINUX_IPV6_RECVPKTINFO:
164 		return (IPV6_RECVPKTINFO);
165 	case LINUX_IPV6_PKTINFO:
166 		return (IPV6_PKTINFO);
167 	case LINUX_IPV6_RECVHOPLIMIT:
168 		return (IPV6_RECVHOPLIMIT);
169 	case LINUX_IPV6_HOPLIMIT:
170 		return (IPV6_HOPLIMIT);
171 	case LINUX_IPV6_RECVHOPOPTS:
172 		return (IPV6_RECVHOPOPTS);
173 	case LINUX_IPV6_HOPOPTS:
174 		return (IPV6_HOPOPTS);
175 	case LINUX_IPV6_RTHDRDSTOPTS:
176 		return (IPV6_RTHDRDSTOPTS);
177 	case LINUX_IPV6_RECVRTHDR:
178 		return (IPV6_RECVRTHDR);
179 	case LINUX_IPV6_RTHDR:
180 		return (IPV6_RTHDR);
181 	case LINUX_IPV6_RECVDSTOPTS:
182 		return (IPV6_RECVDSTOPTS);
183 	case LINUX_IPV6_DSTOPTS:
184 		return (IPV6_DSTOPTS);
185 	case LINUX_IPV6_RECVPATHMTU:
186 		return (IPV6_RECVPATHMTU);
187 	case LINUX_IPV6_PATHMTU:
188 		return (IPV6_PATHMTU);
189 #endif
190 	}
191 	return (-1);
192 }
193 
194 static int
195 linux_to_bsd_so_sockopt(int opt)
196 {
197 
198 	switch (opt) {
199 	case LINUX_SO_DEBUG:
200 		return (SO_DEBUG);
201 	case LINUX_SO_REUSEADDR:
202 		return (SO_REUSEADDR);
203 	case LINUX_SO_TYPE:
204 		return (SO_TYPE);
205 	case LINUX_SO_ERROR:
206 		return (SO_ERROR);
207 	case LINUX_SO_DONTROUTE:
208 		return (SO_DONTROUTE);
209 	case LINUX_SO_BROADCAST:
210 		return (SO_BROADCAST);
211 	case LINUX_SO_SNDBUF:
212 	case LINUX_SO_SNDBUFFORCE:
213 		return (SO_SNDBUF);
214 	case LINUX_SO_RCVBUF:
215 	case LINUX_SO_RCVBUFFORCE:
216 		return (SO_RCVBUF);
217 	case LINUX_SO_KEEPALIVE:
218 		return (SO_KEEPALIVE);
219 	case LINUX_SO_OOBINLINE:
220 		return (SO_OOBINLINE);
221 	case LINUX_SO_LINGER:
222 		return (SO_LINGER);
223 	case LINUX_SO_REUSEPORT:
224 		return (SO_REUSEPORT_LB);
225 	case LINUX_SO_PASSCRED:
226 		return (LOCAL_CREDS_PERSISTENT);
227 	case LINUX_SO_PEERCRED:
228 		return (LOCAL_PEERCRED);
229 	case LINUX_SO_RCVLOWAT:
230 		return (SO_RCVLOWAT);
231 	case LINUX_SO_SNDLOWAT:
232 		return (SO_SNDLOWAT);
233 	case LINUX_SO_RCVTIMEO:
234 		return (SO_RCVTIMEO);
235 	case LINUX_SO_SNDTIMEO:
236 		return (SO_SNDTIMEO);
237 	case LINUX_SO_TIMESTAMP:
238 		return (SO_TIMESTAMP);
239 	case LINUX_SO_ACCEPTCONN:
240 		return (SO_ACCEPTCONN);
241 	case LINUX_SO_PROTOCOL:
242 		return (SO_PROTOCOL);
243 	}
244 	return (-1);
245 }
246 
247 static int
248 linux_to_bsd_tcp_sockopt(int opt)
249 {
250 
251 	switch (opt) {
252 	case LINUX_TCP_NODELAY:
253 		return (TCP_NODELAY);
254 	case LINUX_TCP_MAXSEG:
255 		return (TCP_MAXSEG);
256 	case LINUX_TCP_CORK:
257 		return (TCP_NOPUSH);
258 	case LINUX_TCP_KEEPIDLE:
259 		return (TCP_KEEPIDLE);
260 	case LINUX_TCP_KEEPINTVL:
261 		return (TCP_KEEPINTVL);
262 	case LINUX_TCP_KEEPCNT:
263 		return (TCP_KEEPCNT);
264 	case LINUX_TCP_MD5SIG:
265 		return (TCP_MD5SIG);
266 	}
267 	return (-1);
268 }
269 
270 static int
271 linux_to_bsd_msg_flags(int flags)
272 {
273 	int ret_flags = 0;
274 
275 	if (flags & LINUX_MSG_OOB)
276 		ret_flags |= MSG_OOB;
277 	if (flags & LINUX_MSG_PEEK)
278 		ret_flags |= MSG_PEEK;
279 	if (flags & LINUX_MSG_DONTROUTE)
280 		ret_flags |= MSG_DONTROUTE;
281 	if (flags & LINUX_MSG_CTRUNC)
282 		ret_flags |= MSG_CTRUNC;
283 	if (flags & LINUX_MSG_TRUNC)
284 		ret_flags |= MSG_TRUNC;
285 	if (flags & LINUX_MSG_DONTWAIT)
286 		ret_flags |= MSG_DONTWAIT;
287 	if (flags & LINUX_MSG_EOR)
288 		ret_flags |= MSG_EOR;
289 	if (flags & LINUX_MSG_WAITALL)
290 		ret_flags |= MSG_WAITALL;
291 	if (flags & LINUX_MSG_NOSIGNAL)
292 		ret_flags |= MSG_NOSIGNAL;
293 #if 0 /* not handled */
294 	if (flags & LINUX_MSG_PROXY)
295 		;
296 	if (flags & LINUX_MSG_FIN)
297 		;
298 	if (flags & LINUX_MSG_SYN)
299 		;
300 	if (flags & LINUX_MSG_CONFIRM)
301 		;
302 	if (flags & LINUX_MSG_RST)
303 		;
304 	if (flags & LINUX_MSG_ERRQUEUE)
305 		;
306 #endif
307 	return (ret_flags);
308 }
309 
310 static int
311 linux_to_bsd_cmsg_type(int cmsg_type)
312 {
313 
314 	switch (cmsg_type) {
315 	case LINUX_SCM_RIGHTS:
316 		return (SCM_RIGHTS);
317 	case LINUX_SCM_CREDENTIALS:
318 		return (SCM_CREDS);
319 	}
320 	return (-1);
321 }
322 
323 static int
324 bsd_to_linux_cmsg_type(int cmsg_type)
325 {
326 
327 	switch (cmsg_type) {
328 	case SCM_RIGHTS:
329 		return (LINUX_SCM_RIGHTS);
330 	case SCM_CREDS:
331 		return (LINUX_SCM_CREDENTIALS);
332 	case SCM_TIMESTAMP:
333 		return (LINUX_SCM_TIMESTAMP);
334 	}
335 	return (-1);
336 }
337 
338 static int
339 linux_to_bsd_msghdr(struct msghdr *bhdr, const struct l_msghdr *lhdr)
340 {
341 	if (lhdr->msg_controllen > INT_MAX)
342 		return (ENOBUFS);
343 
344 	bhdr->msg_name		= PTRIN(lhdr->msg_name);
345 	bhdr->msg_namelen	= lhdr->msg_namelen;
346 	bhdr->msg_iov		= PTRIN(lhdr->msg_iov);
347 	bhdr->msg_iovlen	= lhdr->msg_iovlen;
348 	bhdr->msg_control	= PTRIN(lhdr->msg_control);
349 
350 	/*
351 	 * msg_controllen is skipped since BSD and LINUX control messages
352 	 * are potentially different sizes (e.g. the cred structure used
353 	 * by SCM_CREDS is different between the two operating system).
354 	 *
355 	 * The caller can set it (if necessary) after converting all the
356 	 * control messages.
357 	 */
358 
359 	bhdr->msg_flags		= linux_to_bsd_msg_flags(lhdr->msg_flags);
360 	return (0);
361 }
362 
363 static int
364 bsd_to_linux_msghdr(const struct msghdr *bhdr, struct l_msghdr *lhdr)
365 {
366 	lhdr->msg_name		= PTROUT(bhdr->msg_name);
367 	lhdr->msg_namelen	= bhdr->msg_namelen;
368 	lhdr->msg_iov		= PTROUT(bhdr->msg_iov);
369 	lhdr->msg_iovlen	= bhdr->msg_iovlen;
370 	lhdr->msg_control	= PTROUT(bhdr->msg_control);
371 
372 	/*
373 	 * msg_controllen is skipped since BSD and LINUX control messages
374 	 * are potentially different sizes (e.g. the cred structure used
375 	 * by SCM_CREDS is different between the two operating system).
376 	 *
377 	 * The caller can set it (if necessary) after converting all the
378 	 * control messages.
379 	 */
380 
381 	/* msg_flags skipped */
382 	return (0);
383 }
384 
385 static int
386 linux_set_socket_flags(int lflags, int *flags)
387 {
388 
389 	if (lflags & ~(LINUX_SOCK_CLOEXEC | LINUX_SOCK_NONBLOCK))
390 		return (EINVAL);
391 	if (lflags & LINUX_SOCK_NONBLOCK)
392 		*flags |= SOCK_NONBLOCK;
393 	if (lflags & LINUX_SOCK_CLOEXEC)
394 		*flags |= SOCK_CLOEXEC;
395 	return (0);
396 }
397 
398 static int
399 linux_copyout_sockaddr(const struct sockaddr *sa, void *uaddr, size_t len)
400 {
401 	struct l_sockaddr *lsa;
402 	int error;
403 
404 	error = bsd_to_linux_sockaddr(sa, &lsa, len);
405 	if (error != 0)
406 		return (error);
407 
408 	error = copyout(lsa, uaddr, len);
409 	free(lsa, M_SONAME);
410 
411 	return (error);
412 }
413 
414 static int
415 linux_sendit(struct thread *td, int s, struct msghdr *mp, int flags,
416     struct mbuf *control, enum uio_seg segflg)
417 {
418 	struct sockaddr *to;
419 	int error, len;
420 
421 	if (mp->msg_name != NULL) {
422 		len = mp->msg_namelen;
423 		error = linux_to_bsd_sockaddr(mp->msg_name, &to, &len);
424 		if (error != 0)
425 			return (error);
426 		mp->msg_name = to;
427 	} else
428 		to = NULL;
429 
430 	error = kern_sendit(td, s, mp, linux_to_bsd_msg_flags(flags), control,
431 	    segflg);
432 
433 	if (to)
434 		free(to, M_SONAME);
435 	return (error);
436 }
437 
438 /* Return 0 if IP_HDRINCL is set for the given socket. */
439 static int
440 linux_check_hdrincl(struct thread *td, int s)
441 {
442 	int error, optval;
443 	socklen_t size_val;
444 
445 	size_val = sizeof(optval);
446 	error = kern_getsockopt(td, s, IPPROTO_IP, IP_HDRINCL,
447 	    &optval, UIO_SYSSPACE, &size_val);
448 	if (error != 0)
449 		return (error);
450 
451 	return (optval == 0);
452 }
453 
454 /*
455  * Updated sendto() when IP_HDRINCL is set:
456  * tweak endian-dependent fields in the IP packet.
457  */
458 static int
459 linux_sendto_hdrincl(struct thread *td, struct linux_sendto_args *linux_args)
460 {
461 /*
462  * linux_ip_copysize defines how many bytes we should copy
463  * from the beginning of the IP packet before we customize it for BSD.
464  * It should include all the fields we modify (ip_len and ip_off).
465  */
466 #define linux_ip_copysize	8
467 
468 	struct ip *packet;
469 	struct msghdr msg;
470 	struct iovec aiov[1];
471 	int error;
472 
473 	/* Check that the packet isn't too big or too small. */
474 	if (linux_args->len < linux_ip_copysize ||
475 	    linux_args->len > IP_MAXPACKET)
476 		return (EINVAL);
477 
478 	packet = (struct ip *)malloc(linux_args->len, M_LINUX, M_WAITOK);
479 
480 	/* Make kernel copy of the packet to be sent */
481 	if ((error = copyin(PTRIN(linux_args->msg), packet,
482 	    linux_args->len)))
483 		goto goout;
484 
485 	/* Convert fields from Linux to BSD raw IP socket format */
486 	packet->ip_len = linux_args->len;
487 	packet->ip_off = ntohs(packet->ip_off);
488 
489 	/* Prepare the msghdr and iovec structures describing the new packet */
490 	msg.msg_name = PTRIN(linux_args->to);
491 	msg.msg_namelen = linux_args->tolen;
492 	msg.msg_iov = aiov;
493 	msg.msg_iovlen = 1;
494 	msg.msg_control = NULL;
495 	msg.msg_flags = 0;
496 	aiov[0].iov_base = (char *)packet;
497 	aiov[0].iov_len = linux_args->len;
498 	error = linux_sendit(td, linux_args->s, &msg, linux_args->flags,
499 	    NULL, UIO_SYSSPACE);
500 goout:
501 	free(packet, M_LINUX);
502 	return (error);
503 }
504 
505 static const char *linux_netlink_names[] = {
506 	[LINUX_NETLINK_ROUTE] = "ROUTE",
507 	[LINUX_NETLINK_SOCK_DIAG] = "SOCK_DIAG",
508 	[LINUX_NETLINK_NFLOG] = "NFLOG",
509 	[LINUX_NETLINK_SELINUX] = "SELINUX",
510 	[LINUX_NETLINK_AUDIT] = "AUDIT",
511 	[LINUX_NETLINK_FIB_LOOKUP] = "FIB_LOOKUP",
512 	[LINUX_NETLINK_NETFILTER] = "NETFILTER",
513 	[LINUX_NETLINK_KOBJECT_UEVENT] = "KOBJECT_UEVENT",
514 };
515 
516 int
517 linux_socket(struct thread *td, struct linux_socket_args *args)
518 {
519 	int domain, retval_socket, type;
520 
521 	type = args->type & LINUX_SOCK_TYPE_MASK;
522 	if (type < 0 || type > LINUX_SOCK_MAX)
523 		return (EINVAL);
524 	retval_socket = linux_set_socket_flags(args->type & ~LINUX_SOCK_TYPE_MASK,
525 		&type);
526 	if (retval_socket != 0)
527 		return (retval_socket);
528 	domain = linux_to_bsd_domain(args->domain);
529 	if (domain == -1) {
530 		/* Mask off SOCK_NONBLOCK / CLOEXEC for error messages. */
531 		type = args->type & LINUX_SOCK_TYPE_MASK;
532 		if (args->domain == LINUX_AF_NETLINK) {
533 			const char *nl_name;
534 
535 			if (args->protocol >= 0 &&
536 			    args->protocol < nitems(linux_netlink_names))
537 				nl_name = linux_netlink_names[args->protocol];
538 			else
539 				nl_name = NULL;
540 			if (nl_name != NULL)
541 				linux_msg(curthread,
542 				    "unsupported socket(AF_NETLINK, %d, "
543 				    "NETLINK_%s)", type, nl_name);
544 			else
545 				linux_msg(curthread,
546 				    "unsupported socket(AF_NETLINK, %d, %d)",
547 				    type, args->protocol);
548 		} else {
549 			linux_msg(curthread, "unsupported socket domain %d, "
550 			    "type %d, protocol %d", args->domain, type,
551 			    args->protocol);
552 		}
553 		return (EAFNOSUPPORT);
554 	}
555 
556 	retval_socket = kern_socket(td, domain, type, args->protocol);
557 	if (retval_socket)
558 		return (retval_socket);
559 
560 	if (type == SOCK_RAW
561 	    && (args->protocol == IPPROTO_RAW || args->protocol == 0)
562 	    && domain == PF_INET) {
563 		/* It's a raw IP socket: set the IP_HDRINCL option. */
564 		int hdrincl;
565 
566 		hdrincl = 1;
567 		/* We ignore any error returned by kern_setsockopt() */
568 		kern_setsockopt(td, td->td_retval[0], IPPROTO_IP, IP_HDRINCL,
569 		    &hdrincl, UIO_SYSSPACE, sizeof(hdrincl));
570 	}
571 #ifdef INET6
572 	/*
573 	 * Linux AF_INET6 socket has IPV6_V6ONLY setsockopt set to 0 by default
574 	 * and some apps depend on this. So, set V6ONLY to 0 for Linux apps.
575 	 * For simplicity we do this unconditionally of the net.inet6.ip6.v6only
576 	 * sysctl value.
577 	 */
578 	if (domain == PF_INET6) {
579 		int v6only;
580 
581 		v6only = 0;
582 		/* We ignore any error returned by setsockopt() */
583 		kern_setsockopt(td, td->td_retval[0], IPPROTO_IPV6, IPV6_V6ONLY,
584 		    &v6only, UIO_SYSSPACE, sizeof(v6only));
585 	}
586 #endif
587 
588 	return (retval_socket);
589 }
590 
591 int
592 linux_bind(struct thread *td, struct linux_bind_args *args)
593 {
594 	struct sockaddr *sa;
595 	int error;
596 
597 	error = linux_to_bsd_sockaddr(PTRIN(args->name), &sa,
598 	    &args->namelen);
599 	if (error != 0)
600 		return (error);
601 
602 	error = kern_bindat(td, AT_FDCWD, args->s, sa);
603 	free(sa, M_SONAME);
604 
605 	/* XXX */
606 	if (error == EADDRNOTAVAIL && args->namelen != sizeof(struct sockaddr_in))
607 		return (EINVAL);
608 	return (error);
609 }
610 
611 int
612 linux_connect(struct thread *td, struct linux_connect_args *args)
613 {
614 	struct socket *so;
615 	struct sockaddr *sa;
616 	struct file *fp;
617 	u_int fflag;
618 	int error;
619 
620 	error = linux_to_bsd_sockaddr(PTRIN(args->name), &sa,
621 	    &args->namelen);
622 	if (error != 0)
623 		return (error);
624 
625 	error = kern_connectat(td, AT_FDCWD, args->s, sa);
626 	free(sa, M_SONAME);
627 	if (error != EISCONN)
628 		return (error);
629 
630 	/*
631 	 * Linux doesn't return EISCONN the first time it occurs,
632 	 * when on a non-blocking socket. Instead it returns the
633 	 * error getsockopt(SOL_SOCKET, SO_ERROR) would return on BSD.
634 	 */
635 	error = getsock_cap(td, args->s, &cap_connect_rights,
636 	    &fp, &fflag, NULL);
637 	if (error != 0)
638 		return (error);
639 
640 	error = EISCONN;
641 	so = fp->f_data;
642 	if (fflag & FNONBLOCK) {
643 		SOCK_LOCK(so);
644 		if (so->so_emuldata == 0)
645 			error = so->so_error;
646 		so->so_emuldata = (void *)1;
647 		SOCK_UNLOCK(so);
648 	}
649 	fdrop(fp, td);
650 
651 	return (error);
652 }
653 
654 int
655 linux_listen(struct thread *td, struct linux_listen_args *args)
656 {
657 
658 	return (kern_listen(td, args->s, args->backlog));
659 }
660 
661 static int
662 linux_accept_common(struct thread *td, int s, l_uintptr_t addr,
663     l_uintptr_t namelen, int flags)
664 {
665 	struct sockaddr *sa;
666 	struct file *fp, *fp1;
667 	int bflags, len;
668 	struct socket *so;
669 	int error, error1;
670 
671 	bflags = 0;
672 	fp = NULL;
673 	sa = NULL;
674 
675 	error = linux_set_socket_flags(flags, &bflags);
676 	if (error != 0)
677 		return (error);
678 
679 	if (PTRIN(addr) == NULL) {
680 		len = 0;
681 		error = kern_accept4(td, s, NULL, NULL, bflags, NULL);
682 	} else {
683 		error = copyin(PTRIN(namelen), &len, sizeof(len));
684 		if (error != 0)
685 			return (error);
686 		if (len < 0)
687 			return (EINVAL);
688 		error = kern_accept4(td, s, &sa, &len, bflags, &fp);
689 	}
690 
691 	/*
692 	 * Translate errno values into ones used by Linux.
693 	 */
694 	if (error != 0) {
695 		/*
696 		 * XXX. This is wrong, different sockaddr structures
697 		 * have different sizes.
698 		 */
699 		switch (error) {
700 		case EFAULT:
701 			if (namelen != sizeof(struct sockaddr_in))
702 				error = EINVAL;
703 			break;
704 		case EINVAL:
705 			error1 = getsock_cap(td, s, &cap_accept_rights, &fp1, NULL, NULL);
706 			if (error1 != 0) {
707 				error = error1;
708 				break;
709 			}
710 			so = fp1->f_data;
711 			if (so->so_type == SOCK_DGRAM)
712 				error = EOPNOTSUPP;
713 			fdrop(fp1, td);
714 			break;
715 		}
716 		return (error);
717 	}
718 
719 	if (len != 0) {
720 		error = linux_copyout_sockaddr(sa, PTRIN(addr), len);
721 
722 		/*
723 		 * XXX: We should also copyout the len, shouldn't we?
724 		 */
725 
726 		if (error != 0) {
727 			fdclose(td, fp, td->td_retval[0]);
728 			td->td_retval[0] = 0;
729 		}
730 	}
731 	if (fp != NULL)
732 		fdrop(fp, td);
733 	free(sa, M_SONAME);
734 	return (error);
735 }
736 
737 int
738 linux_accept(struct thread *td, struct linux_accept_args *args)
739 {
740 
741 	return (linux_accept_common(td, args->s, args->addr,
742 	    args->namelen, 0));
743 }
744 
745 int
746 linux_accept4(struct thread *td, struct linux_accept4_args *args)
747 {
748 
749 	return (linux_accept_common(td, args->s, args->addr,
750 	    args->namelen, args->flags));
751 }
752 
753 int
754 linux_getsockname(struct thread *td, struct linux_getsockname_args *args)
755 {
756 	struct sockaddr *sa;
757 	int len, error;
758 
759 	error = copyin(PTRIN(args->namelen), &len, sizeof(len));
760 	if (error != 0)
761 		return (error);
762 
763 	error = kern_getsockname(td, args->s, &sa, &len);
764 	if (error != 0)
765 		return (error);
766 
767 	if (len != 0)
768 		error = linux_copyout_sockaddr(sa, PTRIN(args->addr), len);
769 
770 	free(sa, M_SONAME);
771 	if (error == 0)
772 		error = copyout(&len, PTRIN(args->namelen), sizeof(len));
773 	return (error);
774 }
775 
776 int
777 linux_getpeername(struct thread *td, struct linux_getpeername_args *args)
778 {
779 	struct sockaddr *sa;
780 	int len, error;
781 
782 	error = copyin(PTRIN(args->namelen), &len, sizeof(len));
783 	if (error != 0)
784 		return (error);
785 	if (len < 0)
786 		return (EINVAL);
787 
788 	error = kern_getpeername(td, args->s, &sa, &len);
789 	if (error != 0)
790 		return (error);
791 
792 	if (len != 0)
793 		error = linux_copyout_sockaddr(sa, PTRIN(args->addr), len);
794 
795 	free(sa, M_SONAME);
796 	if (error == 0)
797 		error = copyout(&len, PTRIN(args->namelen), sizeof(len));
798 	return (error);
799 }
800 
801 int
802 linux_socketpair(struct thread *td, struct linux_socketpair_args *args)
803 {
804 	int domain, error, sv[2], type;
805 
806 	domain = linux_to_bsd_domain(args->domain);
807 	if (domain != PF_LOCAL)
808 		return (EAFNOSUPPORT);
809 	type = args->type & LINUX_SOCK_TYPE_MASK;
810 	if (type < 0 || type > LINUX_SOCK_MAX)
811 		return (EINVAL);
812 	error = linux_set_socket_flags(args->type & ~LINUX_SOCK_TYPE_MASK,
813 	    &type);
814 	if (error != 0)
815 		return (error);
816 	if (args->protocol != 0 && args->protocol != PF_UNIX) {
817 		/*
818 		 * Use of PF_UNIX as protocol argument is not right,
819 		 * but Linux does it.
820 		 * Do not map PF_UNIX as its Linux value is identical
821 		 * to FreeBSD one.
822 		 */
823 		return (EPROTONOSUPPORT);
824 	}
825 	error = kern_socketpair(td, domain, type, 0, sv);
826 	if (error != 0)
827                 return (error);
828         error = copyout(sv, PTRIN(args->rsv), 2 * sizeof(int));
829         if (error != 0) {
830                 (void)kern_close(td, sv[0]);
831                 (void)kern_close(td, sv[1]);
832         }
833 	return (error);
834 }
835 
836 #if defined(__i386__) || (defined(__amd64__) && defined(COMPAT_LINUX32))
837 struct linux_send_args {
838 	register_t s;
839 	register_t msg;
840 	register_t len;
841 	register_t flags;
842 };
843 
844 static int
845 linux_send(struct thread *td, struct linux_send_args *args)
846 {
847 	struct sendto_args /* {
848 		int s;
849 		caddr_t buf;
850 		int len;
851 		int flags;
852 		caddr_t to;
853 		int tolen;
854 	} */ bsd_args;
855 	struct file *fp;
856 	int error, fflag;
857 
858 	bsd_args.s = args->s;
859 	bsd_args.buf = (caddr_t)PTRIN(args->msg);
860 	bsd_args.len = args->len;
861 	bsd_args.flags = args->flags;
862 	bsd_args.to = NULL;
863 	bsd_args.tolen = 0;
864 	error = sys_sendto(td, &bsd_args);
865 	if (error == ENOTCONN) {
866 		/*
867 		 * Linux doesn't return ENOTCONN for non-blocking sockets.
868 		 * Instead it returns the EAGAIN.
869 		 */
870 		error = getsock_cap(td, args->s, &cap_send_rights, &fp,
871 		    &fflag, NULL);
872 		if (error == 0) {
873 			if (fflag & FNONBLOCK)
874 				error = EAGAIN;
875 			fdrop(fp, td);
876 		}
877 	}
878 	return (error);
879 }
880 
881 struct linux_recv_args {
882 	register_t s;
883 	register_t msg;
884 	register_t len;
885 	register_t flags;
886 };
887 
888 static int
889 linux_recv(struct thread *td, struct linux_recv_args *args)
890 {
891 	struct recvfrom_args /* {
892 		int s;
893 		caddr_t buf;
894 		int len;
895 		int flags;
896 		struct sockaddr *from;
897 		socklen_t fromlenaddr;
898 	} */ bsd_args;
899 
900 	bsd_args.s = args->s;
901 	bsd_args.buf = (caddr_t)PTRIN(args->msg);
902 	bsd_args.len = args->len;
903 	bsd_args.flags = linux_to_bsd_msg_flags(args->flags);
904 	bsd_args.from = NULL;
905 	bsd_args.fromlenaddr = 0;
906 	return (sys_recvfrom(td, &bsd_args));
907 }
908 #endif /* __i386__ || (__amd64__ && COMPAT_LINUX32) */
909 
910 int
911 linux_sendto(struct thread *td, struct linux_sendto_args *args)
912 {
913 	struct msghdr msg;
914 	struct iovec aiov;
915 
916 	if (linux_check_hdrincl(td, args->s) == 0)
917 		/* IP_HDRINCL set, tweak the packet before sending */
918 		return (linux_sendto_hdrincl(td, args));
919 
920 	msg.msg_name = PTRIN(args->to);
921 	msg.msg_namelen = args->tolen;
922 	msg.msg_iov = &aiov;
923 	msg.msg_iovlen = 1;
924 	msg.msg_control = NULL;
925 	msg.msg_flags = 0;
926 	aiov.iov_base = PTRIN(args->msg);
927 	aiov.iov_len = args->len;
928 	return (linux_sendit(td, args->s, &msg, args->flags, NULL,
929 	    UIO_USERSPACE));
930 }
931 
932 int
933 linux_recvfrom(struct thread *td, struct linux_recvfrom_args *args)
934 {
935 	struct sockaddr *sa;
936 	struct msghdr msg;
937 	struct iovec aiov;
938 	int error, fromlen;
939 
940 	if (PTRIN(args->fromlen) != NULL) {
941 		error = copyin(PTRIN(args->fromlen), &fromlen,
942 		    sizeof(fromlen));
943 		if (error != 0)
944 			return (error);
945 		if (fromlen < 0)
946 			return (EINVAL);
947 		sa = malloc(fromlen, M_SONAME, M_WAITOK);
948 	} else {
949 		fromlen = 0;
950 		sa = NULL;
951 	}
952 
953 	msg.msg_name = sa;
954 	msg.msg_namelen = fromlen;
955 	msg.msg_iov = &aiov;
956 	msg.msg_iovlen = 1;
957 	aiov.iov_base = PTRIN(args->buf);
958 	aiov.iov_len = args->len;
959 	msg.msg_control = 0;
960 	msg.msg_flags = linux_to_bsd_msg_flags(args->flags);
961 
962 	error = kern_recvit(td, args->s, &msg, UIO_SYSSPACE, NULL);
963 	if (error != 0)
964 		goto out;
965 
966 	if (PTRIN(args->from) != NULL)
967 		error = linux_copyout_sockaddr(sa, PTRIN(args->from), msg.msg_namelen);
968 
969 	if (error == 0 && PTRIN(args->fromlen) != NULL)
970 		error = copyout(&msg.msg_namelen, PTRIN(args->fromlen),
971 		    sizeof(msg.msg_namelen));
972 out:
973 	free(sa, M_SONAME);
974 	return (error);
975 }
976 
977 static int
978 linux_sendmsg_common(struct thread *td, l_int s, struct l_msghdr *msghdr,
979     l_uint flags)
980 {
981 	struct cmsghdr *cmsg;
982 	struct mbuf *control;
983 	struct msghdr msg;
984 	struct l_cmsghdr linux_cmsg;
985 	struct l_cmsghdr *ptr_cmsg;
986 	struct l_msghdr linux_msghdr;
987 	struct iovec *iov;
988 	socklen_t datalen;
989 	struct sockaddr *sa;
990 	struct socket *so;
991 	sa_family_t sa_family;
992 	struct file *fp;
993 	void *data;
994 	l_size_t len;
995 	l_size_t clen;
996 	int error, fflag;
997 
998 	error = copyin(msghdr, &linux_msghdr, sizeof(linux_msghdr));
999 	if (error != 0)
1000 		return (error);
1001 
1002 	/*
1003 	 * Some Linux applications (ping) define a non-NULL control data
1004 	 * pointer, but a msg_controllen of 0, which is not allowed in the
1005 	 * FreeBSD system call interface.  NULL the msg_control pointer in
1006 	 * order to handle this case.  This should be checked, but allows the
1007 	 * Linux ping to work.
1008 	 */
1009 	if (PTRIN(linux_msghdr.msg_control) != NULL &&
1010 	    linux_msghdr.msg_controllen == 0)
1011 		linux_msghdr.msg_control = PTROUT(NULL);
1012 
1013 	error = linux_to_bsd_msghdr(&msg, &linux_msghdr);
1014 	if (error != 0)
1015 		return (error);
1016 
1017 #ifdef COMPAT_LINUX32
1018 	error = linux32_copyiniov(PTRIN(msg.msg_iov), msg.msg_iovlen,
1019 	    &iov, EMSGSIZE);
1020 #else
1021 	error = copyiniov(msg.msg_iov, msg.msg_iovlen, &iov, EMSGSIZE);
1022 #endif
1023 	if (error != 0)
1024 		return (error);
1025 
1026 	control = NULL;
1027 
1028 	error = kern_getsockname(td, s, &sa, &datalen);
1029 	if (error != 0)
1030 		goto bad;
1031 	sa_family = sa->sa_family;
1032 	free(sa, M_SONAME);
1033 
1034 	if (flags & LINUX_MSG_OOB) {
1035 		error = EOPNOTSUPP;
1036 		if (sa_family == AF_UNIX)
1037 			goto bad;
1038 
1039 		error = getsock_cap(td, s, &cap_send_rights, &fp,
1040 		    &fflag, NULL);
1041 		if (error != 0)
1042 			goto bad;
1043 		so = fp->f_data;
1044 		if (so->so_type != SOCK_STREAM)
1045 			error = EOPNOTSUPP;
1046 		fdrop(fp, td);
1047 		if (error != 0)
1048 			goto bad;
1049 	}
1050 
1051 	if (linux_msghdr.msg_controllen >= sizeof(struct l_cmsghdr)) {
1052 		error = ENOBUFS;
1053 		control = m_get(M_WAITOK, MT_CONTROL);
1054 		MCLGET(control, M_WAITOK);
1055 		data = mtod(control, void *);
1056 		datalen = 0;
1057 
1058 		ptr_cmsg = PTRIN(linux_msghdr.msg_control);
1059 		clen = linux_msghdr.msg_controllen;
1060 		do {
1061 			error = copyin(ptr_cmsg, &linux_cmsg,
1062 			    sizeof(struct l_cmsghdr));
1063 			if (error != 0)
1064 				goto bad;
1065 
1066 			error = EINVAL;
1067 			if (linux_cmsg.cmsg_len < sizeof(struct l_cmsghdr) ||
1068 			    linux_cmsg.cmsg_len > clen)
1069 				goto bad;
1070 
1071 			if (datalen + CMSG_HDRSZ > MCLBYTES)
1072 				goto bad;
1073 
1074 			/*
1075 			 * Now we support only SCM_RIGHTS and SCM_CRED,
1076 			 * so return EINVAL in any other cmsg_type
1077 			 */
1078 			cmsg = data;
1079 			cmsg->cmsg_type =
1080 			    linux_to_bsd_cmsg_type(linux_cmsg.cmsg_type);
1081 			cmsg->cmsg_level =
1082 			    linux_to_bsd_sockopt_level(linux_cmsg.cmsg_level);
1083 			if (cmsg->cmsg_type == -1
1084 			    || cmsg->cmsg_level != SOL_SOCKET) {
1085 				linux_msg(curthread,
1086 				    "unsupported sendmsg cmsg level %d type %d",
1087 				    linux_cmsg.cmsg_level, linux_cmsg.cmsg_type);
1088 				goto bad;
1089 			}
1090 
1091 			/*
1092 			 * Some applications (e.g. pulseaudio) attempt to
1093 			 * send ancillary data even if the underlying protocol
1094 			 * doesn't support it which is not allowed in the
1095 			 * FreeBSD system call interface.
1096 			 */
1097 			if (sa_family != AF_UNIX)
1098 				goto next;
1099 
1100 			if (cmsg->cmsg_type == SCM_CREDS) {
1101 				len = sizeof(struct cmsgcred);
1102 				if (datalen + CMSG_SPACE(len) > MCLBYTES)
1103 					goto bad;
1104 
1105 				/*
1106 				 * The lower levels will fill in the structure
1107 				 */
1108 				memset(CMSG_DATA(data), 0, len);
1109 			} else {
1110 				len = linux_cmsg.cmsg_len - L_CMSG_HDRSZ;
1111 				if (datalen + CMSG_SPACE(len) < datalen ||
1112 				    datalen + CMSG_SPACE(len) > MCLBYTES)
1113 					goto bad;
1114 
1115 				error = copyin(LINUX_CMSG_DATA(ptr_cmsg),
1116 				    CMSG_DATA(data), len);
1117 				if (error != 0)
1118 					goto bad;
1119 			}
1120 
1121 			cmsg->cmsg_len = CMSG_LEN(len);
1122 			data = (char *)data + CMSG_SPACE(len);
1123 			datalen += CMSG_SPACE(len);
1124 
1125 next:
1126 			if (clen <= LINUX_CMSG_ALIGN(linux_cmsg.cmsg_len))
1127 				break;
1128 
1129 			clen -= LINUX_CMSG_ALIGN(linux_cmsg.cmsg_len);
1130 			ptr_cmsg = (struct l_cmsghdr *)((char *)ptr_cmsg +
1131 			    LINUX_CMSG_ALIGN(linux_cmsg.cmsg_len));
1132 		} while(clen >= sizeof(struct l_cmsghdr));
1133 
1134 		control->m_len = datalen;
1135 		if (datalen == 0) {
1136 			m_freem(control);
1137 			control = NULL;
1138 		}
1139 	}
1140 
1141 	msg.msg_iov = iov;
1142 	msg.msg_flags = 0;
1143 	error = linux_sendit(td, s, &msg, flags, control, UIO_USERSPACE);
1144 	control = NULL;
1145 
1146 bad:
1147 	m_freem(control);
1148 	free(iov, M_IOV);
1149 	return (error);
1150 }
1151 
1152 int
1153 linux_sendmsg(struct thread *td, struct linux_sendmsg_args *args)
1154 {
1155 
1156 	return (linux_sendmsg_common(td, args->s, PTRIN(args->msg),
1157 	    args->flags));
1158 }
1159 
1160 int
1161 linux_sendmmsg(struct thread *td, struct linux_sendmmsg_args *args)
1162 {
1163 	struct l_mmsghdr *msg;
1164 	l_uint retval;
1165 	int error, datagrams;
1166 
1167 	if (args->vlen > UIO_MAXIOV)
1168 		args->vlen = UIO_MAXIOV;
1169 
1170 	msg = PTRIN(args->msg);
1171 	datagrams = 0;
1172 	while (datagrams < args->vlen) {
1173 		error = linux_sendmsg_common(td, args->s, &msg->msg_hdr,
1174 		    args->flags);
1175 		if (error != 0)
1176 			break;
1177 
1178 		retval = td->td_retval[0];
1179 		error = copyout(&retval, &msg->msg_len, sizeof(msg->msg_len));
1180 		if (error != 0)
1181 			break;
1182 		++msg;
1183 		++datagrams;
1184 	}
1185 	if (error == 0)
1186 		td->td_retval[0] = datagrams;
1187 	return (error);
1188 }
1189 
1190 static int
1191 linux_recvmsg_common(struct thread *td, l_int s, struct l_msghdr *msghdr,
1192     l_uint flags, struct msghdr *msg)
1193 {
1194 	struct cmsghdr *cm;
1195 	struct cmsgcred *cmcred;
1196 	struct l_cmsghdr *linux_cmsg = NULL;
1197 	struct l_ucred linux_ucred;
1198 	socklen_t datalen, maxlen, outlen;
1199 	struct l_msghdr linux_msghdr;
1200 	struct iovec *iov, *uiov;
1201 	struct mbuf *control = NULL;
1202 	struct mbuf **controlp;
1203 	struct timeval *ftmvl;
1204 	struct sockaddr *sa;
1205 	l_timeval ltmvl;
1206 	caddr_t outbuf;
1207 	void *data;
1208 	int error, i, fd, fds, *fdp;
1209 
1210 	error = copyin(msghdr, &linux_msghdr, sizeof(linux_msghdr));
1211 	if (error != 0)
1212 		return (error);
1213 
1214 	error = linux_to_bsd_msghdr(msg, &linux_msghdr);
1215 	if (error != 0)
1216 		return (error);
1217 
1218 #ifdef COMPAT_LINUX32
1219 	error = linux32_copyiniov(PTRIN(msg->msg_iov), msg->msg_iovlen,
1220 	    &iov, EMSGSIZE);
1221 #else
1222 	error = copyiniov(msg->msg_iov, msg->msg_iovlen, &iov, EMSGSIZE);
1223 #endif
1224 	if (error != 0)
1225 		return (error);
1226 
1227 	if (msg->msg_name != NULL && msg->msg_namelen > 0) {
1228 		msg->msg_namelen = min(msg->msg_namelen, SOCK_MAXADDRLEN);
1229 		sa = malloc(msg->msg_namelen, M_SONAME, M_WAITOK);
1230 		msg->msg_name = sa;
1231 	} else {
1232 		sa = NULL;
1233 		msg->msg_name = NULL;
1234 	}
1235 
1236 	uiov = msg->msg_iov;
1237 	msg->msg_iov = iov;
1238 	controlp = (msg->msg_control != NULL) ? &control : NULL;
1239 	error = kern_recvit(td, s, msg, UIO_SYSSPACE, controlp);
1240 	msg->msg_iov = uiov;
1241 	if (error != 0)
1242 		goto bad;
1243 
1244 	/*
1245 	 * Note that kern_recvit() updates msg->msg_namelen.
1246 	 */
1247 	if (msg->msg_name != NULL && msg->msg_namelen > 0) {
1248 		msg->msg_name = PTRIN(linux_msghdr.msg_name);
1249 		error = linux_copyout_sockaddr(sa,
1250 		    PTRIN(msg->msg_name), msg->msg_namelen);
1251 		if (error != 0)
1252 			goto bad;
1253 	}
1254 
1255 	error = bsd_to_linux_msghdr(msg, &linux_msghdr);
1256 	if (error != 0)
1257 		goto bad;
1258 
1259 	maxlen = linux_msghdr.msg_controllen;
1260 	linux_msghdr.msg_controllen = 0;
1261 	if (control) {
1262 		linux_cmsg = malloc(L_CMSG_HDRSZ, M_LINUX, M_WAITOK | M_ZERO);
1263 
1264 		msg->msg_control = mtod(control, struct cmsghdr *);
1265 		msg->msg_controllen = control->m_len;
1266 
1267 		cm = CMSG_FIRSTHDR(msg);
1268 		outbuf = PTRIN(linux_msghdr.msg_control);
1269 		outlen = 0;
1270 		while (cm != NULL) {
1271 			linux_cmsg->cmsg_type =
1272 			    bsd_to_linux_cmsg_type(cm->cmsg_type);
1273 			linux_cmsg->cmsg_level =
1274 			    bsd_to_linux_sockopt_level(cm->cmsg_level);
1275 			if (linux_cmsg->cmsg_type == -1 ||
1276 			    cm->cmsg_level != SOL_SOCKET) {
1277 				linux_msg(curthread,
1278 				    "unsupported recvmsg cmsg level %d type %d",
1279 				    cm->cmsg_level, cm->cmsg_type);
1280 				error = EINVAL;
1281 				goto bad;
1282 			}
1283 
1284 			data = CMSG_DATA(cm);
1285 			datalen = (caddr_t)cm + cm->cmsg_len - (caddr_t)data;
1286 
1287 			switch (cm->cmsg_type) {
1288 			case SCM_RIGHTS:
1289 				if (flags & LINUX_MSG_CMSG_CLOEXEC) {
1290 					fds = datalen / sizeof(int);
1291 					fdp = data;
1292 					for (i = 0; i < fds; i++) {
1293 						fd = *fdp++;
1294 						(void)kern_fcntl(td, fd,
1295 						    F_SETFD, FD_CLOEXEC);
1296 					}
1297 				}
1298 				break;
1299 
1300 			case SCM_CREDS:
1301 				/*
1302 				 * Currently LOCAL_CREDS is never in
1303 				 * effect for Linux so no need to worry
1304 				 * about sockcred
1305 				 */
1306 				if (datalen != sizeof(*cmcred)) {
1307 					error = EMSGSIZE;
1308 					goto bad;
1309 				}
1310 				cmcred = (struct cmsgcred *)data;
1311 				bzero(&linux_ucred, sizeof(linux_ucred));
1312 				linux_ucred.pid = cmcred->cmcred_pid;
1313 				linux_ucred.uid = cmcred->cmcred_uid;
1314 				linux_ucred.gid = cmcred->cmcred_gid;
1315 				data = &linux_ucred;
1316 				datalen = sizeof(linux_ucred);
1317 				break;
1318 
1319 			case SCM_TIMESTAMP:
1320 				if (datalen != sizeof(struct timeval)) {
1321 					error = EMSGSIZE;
1322 					goto bad;
1323 				}
1324 				ftmvl = (struct timeval *)data;
1325 				ltmvl.tv_sec = ftmvl->tv_sec;
1326 				ltmvl.tv_usec = ftmvl->tv_usec;
1327 				data = &ltmvl;
1328 				datalen = sizeof(ltmvl);
1329 				break;
1330 			}
1331 
1332 			if (outlen + LINUX_CMSG_LEN(datalen) > maxlen) {
1333 				if (outlen == 0) {
1334 					error = EMSGSIZE;
1335 					goto bad;
1336 				} else {
1337 					linux_msghdr.msg_flags |= LINUX_MSG_CTRUNC;
1338 					m_dispose_extcontrolm(control);
1339 					goto out;
1340 				}
1341 			}
1342 
1343 			linux_cmsg->cmsg_len = LINUX_CMSG_LEN(datalen);
1344 
1345 			error = copyout(linux_cmsg, outbuf, L_CMSG_HDRSZ);
1346 			if (error != 0)
1347 				goto bad;
1348 			outbuf += L_CMSG_HDRSZ;
1349 
1350 			error = copyout(data, outbuf, datalen);
1351 			if (error != 0)
1352 				goto bad;
1353 
1354 			outbuf += LINUX_CMSG_ALIGN(datalen);
1355 			outlen += LINUX_CMSG_LEN(datalen);
1356 
1357 			cm = CMSG_NXTHDR(msg, cm);
1358 		}
1359 		linux_msghdr.msg_controllen = outlen;
1360 	}
1361 
1362 out:
1363 	error = copyout(&linux_msghdr, msghdr, sizeof(linux_msghdr));
1364 
1365 bad:
1366 	if (control != NULL) {
1367 		if (error != 0)
1368 			m_dispose_extcontrolm(control);
1369 		m_freem(control);
1370 	}
1371 	free(iov, M_IOV);
1372 	free(linux_cmsg, M_LINUX);
1373 	free(sa, M_SONAME);
1374 
1375 	return (error);
1376 }
1377 
1378 int
1379 linux_recvmsg(struct thread *td, struct linux_recvmsg_args *args)
1380 {
1381 	struct msghdr bsd_msg;
1382 
1383 	return (linux_recvmsg_common(td, args->s, PTRIN(args->msg),
1384 	    args->flags, &bsd_msg));
1385 }
1386 
1387 int
1388 linux_recvmmsg(struct thread *td, struct linux_recvmmsg_args *args)
1389 {
1390 	struct l_mmsghdr *msg;
1391 	struct msghdr bsd_msg;
1392 	struct l_timespec lts;
1393 	struct timespec ts, tts;
1394 	l_uint retval;
1395 	int error, datagrams;
1396 
1397 	if (args->timeout) {
1398 		error = copyin(args->timeout, &lts, sizeof(struct l_timespec));
1399 		if (error != 0)
1400 			return (error);
1401 		error = linux_to_native_timespec(&ts, &lts);
1402 		if (error != 0)
1403 			return (error);
1404 		getnanotime(&tts);
1405 		timespecadd(&tts, &ts, &tts);
1406 	}
1407 
1408 	msg = PTRIN(args->msg);
1409 	datagrams = 0;
1410 	while (datagrams < args->vlen) {
1411 		error = linux_recvmsg_common(td, args->s, &msg->msg_hdr,
1412 		    args->flags & ~LINUX_MSG_WAITFORONE, &bsd_msg);
1413 		if (error != 0)
1414 			break;
1415 
1416 		retval = td->td_retval[0];
1417 		error = copyout(&retval, &msg->msg_len, sizeof(msg->msg_len));
1418 		if (error != 0)
1419 			break;
1420 		++msg;
1421 		++datagrams;
1422 
1423 		/*
1424 		 * MSG_WAITFORONE turns on MSG_DONTWAIT after one packet.
1425 		 */
1426 		if (args->flags & LINUX_MSG_WAITFORONE)
1427 			args->flags |= LINUX_MSG_DONTWAIT;
1428 
1429 		/*
1430 		 * See BUGS section of recvmmsg(2).
1431 		 */
1432 		if (args->timeout) {
1433 			getnanotime(&ts);
1434 			timespecsub(&ts, &tts, &ts);
1435 			if (!timespecisset(&ts) || ts.tv_sec > 0)
1436 				break;
1437 		}
1438 		/* Out of band data, return right away. */
1439 		if (bsd_msg.msg_flags & MSG_OOB)
1440 			break;
1441 	}
1442 	if (error == 0)
1443 		td->td_retval[0] = datagrams;
1444 	return (error);
1445 }
1446 
1447 int
1448 linux_shutdown(struct thread *td, struct linux_shutdown_args *args)
1449 {
1450 
1451 	return (kern_shutdown(td, args->s, args->how));
1452 }
1453 
1454 int
1455 linux_setsockopt(struct thread *td, struct linux_setsockopt_args *args)
1456 {
1457 	l_timeval linux_tv;
1458 	struct sockaddr *sa;
1459 	struct timeval tv;
1460 	socklen_t len;
1461 	int error, level, name;
1462 
1463 	level = linux_to_bsd_sockopt_level(args->level);
1464 	switch (level) {
1465 	case SOL_SOCKET:
1466 		name = linux_to_bsd_so_sockopt(args->optname);
1467 		switch (name) {
1468 		case LOCAL_CREDS_PERSISTENT:
1469 			level = SOL_LOCAL;
1470 			break;
1471 		case SO_RCVTIMEO:
1472 			/* FALLTHROUGH */
1473 		case SO_SNDTIMEO:
1474 			error = copyin(PTRIN(args->optval), &linux_tv,
1475 			    sizeof(linux_tv));
1476 			if (error != 0)
1477 				return (error);
1478 			tv.tv_sec = linux_tv.tv_sec;
1479 			tv.tv_usec = linux_tv.tv_usec;
1480 			return (kern_setsockopt(td, args->s, level,
1481 			    name, &tv, UIO_SYSSPACE, sizeof(tv)));
1482 			/* NOTREACHED */
1483 		default:
1484 			break;
1485 		}
1486 		break;
1487 	case IPPROTO_IP:
1488 		if (args->optname == LINUX_IP_RECVERR &&
1489 		    linux_ignore_ip_recverr) {
1490 			/*
1491 			 * XXX: This is a hack to unbreak DNS resolution
1492 			 *	with glibc 2.30 and above.
1493 			 */
1494 			return (0);
1495 		}
1496 		name = linux_to_bsd_ip_sockopt(args->optname);
1497 		break;
1498 	case IPPROTO_IPV6:
1499 		name = linux_to_bsd_ip6_sockopt(args->optname);
1500 		break;
1501 	case IPPROTO_TCP:
1502 		name = linux_to_bsd_tcp_sockopt(args->optname);
1503 		break;
1504 	default:
1505 		name = -1;
1506 		break;
1507 	}
1508 	if (name == -1) {
1509 		linux_msg(curthread,
1510 		    "unsupported setsockopt level %d optname %d",
1511 		    args->level, args->optname);
1512 		return (ENOPROTOOPT);
1513 	}
1514 
1515 	if (name == IPV6_NEXTHOP) {
1516 		len = args->optlen;
1517 		error = linux_to_bsd_sockaddr(PTRIN(args->optval), &sa, &len);
1518 		if (error != 0)
1519 			return (error);
1520 
1521 		error = kern_setsockopt(td, args->s, level,
1522 		    name, sa, UIO_SYSSPACE, len);
1523 		free(sa, M_SONAME);
1524 	} else {
1525 		error = kern_setsockopt(td, args->s, level,
1526 		    name, PTRIN(args->optval), UIO_USERSPACE, args->optlen);
1527 	}
1528 
1529 	return (error);
1530 }
1531 
1532 int
1533 linux_getsockopt(struct thread *td, struct linux_getsockopt_args *args)
1534 {
1535 	l_timeval linux_tv;
1536 	struct timeval tv;
1537 	socklen_t tv_len, xulen, len;
1538 	struct sockaddr *sa;
1539 	struct xucred xu;
1540 	struct l_ucred lxu;
1541 	int error, level, name, newval;
1542 
1543 	level = linux_to_bsd_sockopt_level(args->level);
1544 	switch (level) {
1545 	case SOL_SOCKET:
1546 		name = linux_to_bsd_so_sockopt(args->optname);
1547 		switch (name) {
1548 		case LOCAL_CREDS_PERSISTENT:
1549 			level = SOL_LOCAL;
1550 			break;
1551 		case SO_RCVTIMEO:
1552 			/* FALLTHROUGH */
1553 		case SO_SNDTIMEO:
1554 			tv_len = sizeof(tv);
1555 			error = kern_getsockopt(td, args->s, level,
1556 			    name, &tv, UIO_SYSSPACE, &tv_len);
1557 			if (error != 0)
1558 				return (error);
1559 			linux_tv.tv_sec = tv.tv_sec;
1560 			linux_tv.tv_usec = tv.tv_usec;
1561 			return (copyout(&linux_tv, PTRIN(args->optval),
1562 			    sizeof(linux_tv)));
1563 			/* NOTREACHED */
1564 		case LOCAL_PEERCRED:
1565 			if (args->optlen < sizeof(lxu))
1566 				return (EINVAL);
1567 			/*
1568 			 * LOCAL_PEERCRED is not served at the SOL_SOCKET level,
1569 			 * but by the Unix socket's level 0.
1570 			 */
1571 			level = 0;
1572 			xulen = sizeof(xu);
1573 			error = kern_getsockopt(td, args->s, level,
1574 			    name, &xu, UIO_SYSSPACE, &xulen);
1575 			if (error != 0)
1576 				return (error);
1577 			lxu.pid = xu.cr_pid;
1578 			lxu.uid = xu.cr_uid;
1579 			lxu.gid = xu.cr_gid;
1580 			return (copyout(&lxu, PTRIN(args->optval), sizeof(lxu)));
1581 			/* NOTREACHED */
1582 		case SO_ERROR:
1583 			len = sizeof(newval);
1584 			error = kern_getsockopt(td, args->s, level,
1585 			    name, &newval, UIO_SYSSPACE, &len);
1586 			if (error != 0)
1587 				return (error);
1588 			newval = -bsd_to_linux_errno(newval);
1589 			return (copyout(&newval, PTRIN(args->optval), len));
1590 			/* NOTREACHED */
1591 		default:
1592 			break;
1593 		}
1594 		break;
1595 	case IPPROTO_IP:
1596 		name = linux_to_bsd_ip_sockopt(args->optname);
1597 		break;
1598 	case IPPROTO_IPV6:
1599 		name = linux_to_bsd_ip6_sockopt(args->optname);
1600 		break;
1601 	case IPPROTO_TCP:
1602 		name = linux_to_bsd_tcp_sockopt(args->optname);
1603 		break;
1604 	default:
1605 		name = -1;
1606 		break;
1607 	}
1608 	if (name == -1) {
1609 		linux_msg(curthread,
1610 		    "unsupported getsockopt level %d optname %d",
1611 		    args->level, args->optname);
1612 		return (EINVAL);
1613 	}
1614 
1615 	if (name == IPV6_NEXTHOP) {
1616 		error = copyin(PTRIN(args->optlen), &len, sizeof(len));
1617                 if (error != 0)
1618                         return (error);
1619 		sa = malloc(len, M_SONAME, M_WAITOK);
1620 
1621 		error = kern_getsockopt(td, args->s, level,
1622 		    name, sa, UIO_SYSSPACE, &len);
1623 		if (error != 0)
1624 			goto out;
1625 
1626 		error = linux_copyout_sockaddr(sa, PTRIN(args->optval), len);
1627 		if (error == 0)
1628 			error = copyout(&len, PTRIN(args->optlen),
1629 			    sizeof(len));
1630 out:
1631 		free(sa, M_SONAME);
1632 	} else {
1633 		if (args->optval) {
1634 			error = copyin(PTRIN(args->optlen), &len, sizeof(len));
1635 			if (error != 0)
1636 				return (error);
1637 		}
1638 		error = kern_getsockopt(td, args->s, level,
1639 		    name, PTRIN(args->optval), UIO_USERSPACE, &len);
1640 		if (error == 0)
1641 			error = copyout(&len, PTRIN(args->optlen),
1642 			    sizeof(len));
1643 	}
1644 
1645 	return (error);
1646 }
1647 
1648 static int
1649 linux_sendfile_common(struct thread *td, l_int out, l_int in,
1650     l_loff_t *offset, l_size_t count)
1651 {
1652 	off_t bytes_read;
1653 	int error;
1654 	l_loff_t current_offset;
1655 	struct file *fp;
1656 
1657 	AUDIT_ARG_FD(in);
1658 	error = fget_read(td, in, &cap_pread_rights, &fp);
1659 	if (error != 0)
1660 		return (error);
1661 
1662 	if (offset != NULL) {
1663 		current_offset = *offset;
1664 	} else {
1665 		error = (fp->f_ops->fo_flags & DFLAG_SEEKABLE) != 0 ?
1666 		    fo_seek(fp, 0, SEEK_CUR, td) : ESPIPE;
1667 		if (error != 0)
1668 			goto drop;
1669 		current_offset = td->td_uretoff.tdu_off;
1670 	}
1671 
1672 	bytes_read = 0;
1673 
1674 	/* Linux cannot have 0 count. */
1675 	if (count <= 0 || current_offset < 0) {
1676 		error = EINVAL;
1677 		goto drop;
1678 	}
1679 
1680 	error = fo_sendfile(fp, out, NULL, NULL, current_offset, count,
1681 	    &bytes_read, 0, td);
1682 	if (error != 0)
1683 		goto drop;
1684 	current_offset += bytes_read;
1685 
1686 	if (offset != NULL) {
1687 		*offset = current_offset;
1688 	} else {
1689 		error = fo_seek(fp, current_offset, SEEK_SET, td);
1690 		if (error != 0)
1691 			goto drop;
1692 	}
1693 
1694 	td->td_retval[0] = (ssize_t)bytes_read;
1695 drop:
1696 	fdrop(fp, td);
1697 	return (error);
1698 }
1699 
1700 int
1701 linux_sendfile(struct thread *td, struct linux_sendfile_args *arg)
1702 {
1703 	/*
1704 	 * Differences between FreeBSD and Linux sendfile:
1705 	 * - Linux doesn't send anything when count is 0 (FreeBSD uses 0 to
1706 	 *   mean send the whole file.)  In linux_sendfile given fds are still
1707 	 *   checked for validity when the count is 0.
1708 	 * - Linux can send to any fd whereas FreeBSD only supports sockets.
1709 	 *   The same restriction follows for linux_sendfile.
1710 	 * - Linux doesn't have an equivalent for FreeBSD's flags and sf_hdtr.
1711 	 * - Linux takes an offset pointer and updates it to the read location.
1712 	 *   FreeBSD takes in an offset and a 'bytes read' parameter which is
1713 	 *   only filled if it isn't NULL.  We use this parameter to update the
1714 	 *   offset pointer if it exists.
1715 	 * - Linux sendfile returns bytes read on success while FreeBSD
1716 	 *   returns 0.  We use the 'bytes read' parameter to get this value.
1717 	 */
1718 
1719 	l_loff_t offset64;
1720 	l_long offset;
1721 	int ret;
1722 	int error;
1723 
1724 	if (arg->offset != NULL) {
1725 		error = copyin(arg->offset, &offset, sizeof(offset));
1726 		if (error != 0)
1727 			return (error);
1728 		offset64 = (l_loff_t)offset;
1729 	}
1730 
1731 	ret = linux_sendfile_common(td, arg->out, arg->in,
1732 	    arg->offset != NULL ? &offset64 : NULL, arg->count);
1733 
1734 	if (arg->offset != NULL) {
1735 #if defined(__i386__) || defined(__arm__) || \
1736     (defined(__amd64__) && defined(COMPAT_LINUX32))
1737 		if (offset64 > INT32_MAX)
1738 			return (EOVERFLOW);
1739 #endif
1740 		offset = (l_long)offset64;
1741 		error = copyout(&offset, arg->offset, sizeof(offset));
1742 		if (error != 0)
1743 			return (error);
1744 	}
1745 
1746 	return (ret);
1747 }
1748 
1749 #if defined(__i386__) || defined(__arm__) || \
1750     (defined(__amd64__) && defined(COMPAT_LINUX32))
1751 
1752 int
1753 linux_sendfile64(struct thread *td, struct linux_sendfile64_args *arg)
1754 {
1755 	l_loff_t offset;
1756 	int ret;
1757 	int error;
1758 
1759 	if (arg->offset != NULL) {
1760 		error = copyin(arg->offset, &offset, sizeof(offset));
1761 		if (error != 0)
1762 			return (error);
1763 	}
1764 
1765 	ret = linux_sendfile_common(td, arg->out, arg->in,
1766 		arg->offset != NULL ? &offset : NULL, arg->count);
1767 
1768 	if (arg->offset != NULL) {
1769 		error = copyout(&offset, arg->offset, sizeof(offset));
1770 		if (error != 0)
1771 			return (error);
1772 	}
1773 
1774 	return (ret);
1775 }
1776 
1777 /* Argument list sizes for linux_socketcall */
1778 static const unsigned char lxs_args_cnt[] = {
1779 	0 /* unused*/,		3 /* socket */,
1780 	3 /* bind */,		3 /* connect */,
1781 	2 /* listen */,		3 /* accept */,
1782 	3 /* getsockname */,	3 /* getpeername */,
1783 	4 /* socketpair */,	4 /* send */,
1784 	4 /* recv */,		6 /* sendto */,
1785 	6 /* recvfrom */,	2 /* shutdown */,
1786 	5 /* setsockopt */,	5 /* getsockopt */,
1787 	3 /* sendmsg */,	3 /* recvmsg */,
1788 	4 /* accept4 */,	5 /* recvmmsg */,
1789 	4 /* sendmmsg */,	4 /* sendfile */
1790 };
1791 #define	LINUX_ARGS_CNT		(nitems(lxs_args_cnt) - 1)
1792 #define	LINUX_ARG_SIZE(x)	(lxs_args_cnt[x] * sizeof(l_ulong))
1793 
1794 int
1795 linux_socketcall(struct thread *td, struct linux_socketcall_args *args)
1796 {
1797 	l_ulong a[6];
1798 #if defined(__amd64__) && defined(COMPAT_LINUX32)
1799 	register_t l_args[6];
1800 #endif
1801 	void *arg;
1802 	int error;
1803 
1804 	if (args->what < LINUX_SOCKET || args->what > LINUX_ARGS_CNT)
1805 		return (EINVAL);
1806 	error = copyin(PTRIN(args->args), a, LINUX_ARG_SIZE(args->what));
1807 	if (error != 0)
1808 		return (error);
1809 
1810 #if defined(__amd64__) && defined(COMPAT_LINUX32)
1811 	for (int i = 0; i < lxs_args_cnt[args->what]; ++i)
1812 		l_args[i] = a[i];
1813 	arg = l_args;
1814 #else
1815 	arg = a;
1816 #endif
1817 	switch (args->what) {
1818 	case LINUX_SOCKET:
1819 		return (linux_socket(td, arg));
1820 	case LINUX_BIND:
1821 		return (linux_bind(td, arg));
1822 	case LINUX_CONNECT:
1823 		return (linux_connect(td, arg));
1824 	case LINUX_LISTEN:
1825 		return (linux_listen(td, arg));
1826 	case LINUX_ACCEPT:
1827 		return (linux_accept(td, arg));
1828 	case LINUX_GETSOCKNAME:
1829 		return (linux_getsockname(td, arg));
1830 	case LINUX_GETPEERNAME:
1831 		return (linux_getpeername(td, arg));
1832 	case LINUX_SOCKETPAIR:
1833 		return (linux_socketpair(td, arg));
1834 	case LINUX_SEND:
1835 		return (linux_send(td, arg));
1836 	case LINUX_RECV:
1837 		return (linux_recv(td, arg));
1838 	case LINUX_SENDTO:
1839 		return (linux_sendto(td, arg));
1840 	case LINUX_RECVFROM:
1841 		return (linux_recvfrom(td, arg));
1842 	case LINUX_SHUTDOWN:
1843 		return (linux_shutdown(td, arg));
1844 	case LINUX_SETSOCKOPT:
1845 		return (linux_setsockopt(td, arg));
1846 	case LINUX_GETSOCKOPT:
1847 		return (linux_getsockopt(td, arg));
1848 	case LINUX_SENDMSG:
1849 		return (linux_sendmsg(td, arg));
1850 	case LINUX_RECVMSG:
1851 		return (linux_recvmsg(td, arg));
1852 	case LINUX_ACCEPT4:
1853 		return (linux_accept4(td, arg));
1854 	case LINUX_RECVMMSG:
1855 		return (linux_recvmmsg(td, arg));
1856 	case LINUX_SENDMMSG:
1857 		return (linux_sendmmsg(td, arg));
1858 	case LINUX_SENDFILE:
1859 		return (linux_sendfile(td, arg));
1860 	}
1861 
1862 	linux_msg(td, "socket type %d not implemented", args->what);
1863 	return (ENOSYS);
1864 }
1865 #endif /* __i386__ || __arm__ || (__amd64__ && COMPAT_LINUX32) */
1866