xref: /freebsd/sys/compat/linux/linux_socket.c (revision 0986ab12e44caea472245845f9a89ced4f137d73)
1 /*-
2  * Copyright (c) 1995 S�ren Schmidt
3  * 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  *    in this position and unchanged.
11  * 2. Redistributions in binary form must reproduce the above copyright
12  *    notice, this list of conditions and the following disclaimer in the
13  *    documentation and/or other materials provided with the distribution.
14  * 3. The name of the author may not be used to endorse or promote products
15  *    derived from this software without specific prior written permission
16  *
17  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
18  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
19  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
20  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
21  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
22  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
26  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 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 #ifndef COMPAT_43
37 #error "Unable to compile Linux-emulator due to missing COMPAT_43 option!"
38 #endif
39 
40 #include <sys/param.h>
41 #include <sys/proc.h>
42 #include <sys/systm.h>
43 #include <sys/sysproto.h>
44 #include <sys/fcntl.h>
45 #include <sys/file.h>
46 #include <sys/limits.h>
47 #include <sys/malloc.h>
48 #include <sys/socket.h>
49 #include <sys/socketvar.h>
50 #include <sys/syscallsubr.h>
51 #include <sys/uio.h>
52 #include <sys/syslog.h>
53 
54 #include <netinet/in.h>
55 #include <netinet/in_systm.h>
56 #include <netinet/ip.h>
57 #ifdef INET6
58 #include <netinet/ip6.h>
59 #include <netinet6/ip6_var.h>
60 #endif
61 
62 #include <machine/../linux/linux.h>
63 #include <machine/../linux/linux_proto.h>
64 #include <compat/linux/linux_socket.h>
65 #include <compat/linux/linux_util.h>
66 
67 static int do_sa_get(struct sockaddr **, const struct osockaddr *, int *,
68     struct malloc_type *);
69 static int linux_to_bsd_domain(int);
70 
71 /*
72  * Reads a linux sockaddr and does any necessary translation.
73  * Linux sockaddrs don't have a length field, only a family.
74  */
75 static int
76 linux_getsockaddr(struct sockaddr **sap, const struct osockaddr *osa, int len)
77 {
78 	int osalen = len;
79 
80 	return (do_sa_get(sap, osa, &osalen, M_SONAME));
81 }
82 
83 /*
84  * Copy the osockaddr structure pointed to by osa to kernel, adjust
85  * family and convert to sockaddr.
86  */
87 static int
88 do_sa_get(struct sockaddr **sap, const struct osockaddr *osa, int *osalen,
89     struct malloc_type *mtype)
90 {
91 	int error=0, bdom;
92 	struct sockaddr *sa;
93 	struct osockaddr *kosa;
94 	int alloclen;
95 #ifdef INET6
96 	int oldv6size;
97 	struct sockaddr_in6 *sin6;
98 #endif
99 
100 	if (*osalen < 2 || *osalen > UCHAR_MAX || !osa)
101 		return (EINVAL);
102 
103 	alloclen = *osalen;
104 #ifdef INET6
105 	oldv6size = 0;
106 	/*
107 	 * Check for old (pre-RFC2553) sockaddr_in6. We may accept it
108 	 * if it's a v4-mapped address, so reserve the proper space
109 	 * for it.
110 	 */
111 	if (alloclen == sizeof (struct sockaddr_in6) - sizeof (u_int32_t)) {
112 		alloclen = sizeof (struct sockaddr_in6);
113 		oldv6size = 1;
114 	}
115 #endif
116 
117 	MALLOC(kosa, struct osockaddr *, alloclen, mtype, M_WAITOK);
118 
119 	if ((error = copyin(osa, kosa, *osalen)))
120 		goto out;
121 
122 	bdom = linux_to_bsd_domain(kosa->sa_family);
123 	if (bdom == -1) {
124 		error = EINVAL;
125 		goto out;
126 	}
127 
128 #ifdef INET6
129 	/*
130 	 * Older Linux IPv6 code uses obsolete RFC2133 struct sockaddr_in6,
131 	 * which lacks the scope id compared with RFC2553 one. If we detect
132 	 * the situation, reject the address and write a message to system log.
133 	 *
134 	 * Still accept addresses for which the scope id is not used.
135 	 */
136 	if (oldv6size && bdom == AF_INET6) {
137 		sin6 = (struct sockaddr_in6 *)kosa;
138 		if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr) ||
139 		    (!IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr) &&
140 		     !IN6_IS_ADDR_SITELOCAL(&sin6->sin6_addr) &&
141 		     !IN6_IS_ADDR_V4COMPAT(&sin6->sin6_addr) &&
142 		     !IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr) &&
143 		     !IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr))) {
144 			sin6->sin6_scope_id = 0;
145 		} else {
146 			log(LOG_DEBUG,
147 			    "obsolete pre-RFC2553 sockaddr_in6 rejected");
148 			error = EINVAL;
149 			goto out;
150 		}
151 	} else
152 #endif
153 	if (bdom == AF_INET)
154 		alloclen = sizeof(struct sockaddr_in);
155 
156 	sa = (struct sockaddr *) kosa;
157 	sa->sa_family = bdom;
158 	sa->sa_len = alloclen;
159 
160 	*sap = sa;
161 	*osalen = alloclen;
162 	return (0);
163 
164 out:
165 	FREE(kosa, mtype);
166 	return (error);
167 }
168 
169 static int
170 linux_to_bsd_domain(int domain)
171 {
172 
173 	switch (domain) {
174 	case LINUX_AF_UNSPEC:
175 		return (AF_UNSPEC);
176 	case LINUX_AF_UNIX:
177 		return (AF_LOCAL);
178 	case LINUX_AF_INET:
179 		return (AF_INET);
180 	case LINUX_AF_INET6:
181 		return (AF_INET6);
182 	case LINUX_AF_AX25:
183 		return (AF_CCITT);
184 	case LINUX_AF_IPX:
185 		return (AF_IPX);
186 	case LINUX_AF_APPLETALK:
187 		return (AF_APPLETALK);
188 	}
189 	return (-1);
190 }
191 
192 #ifndef __alpha__
193 static int
194 bsd_to_linux_domain(int domain)
195 {
196 
197 	switch (domain) {
198 	case AF_UNSPEC:
199 		return (LINUX_AF_UNSPEC);
200 	case AF_LOCAL:
201 		return (LINUX_AF_UNIX);
202 	case AF_INET:
203 		return (LINUX_AF_INET);
204 	case AF_INET6:
205 		return (LINUX_AF_INET6);
206 	case AF_CCITT:
207 		return (LINUX_AF_AX25);
208 	case AF_IPX:
209 		return (LINUX_AF_IPX);
210 	case AF_APPLETALK:
211 		return (LINUX_AF_APPLETALK);
212 	}
213 	return (-1);
214 }
215 
216 static int
217 linux_to_bsd_sockopt_level(int level)
218 {
219 
220 	switch (level) {
221 	case LINUX_SOL_SOCKET:
222 		return (SOL_SOCKET);
223 	}
224 	return (level);
225 }
226 
227 static int
228 bsd_to_linux_sockopt_level(int level)
229 {
230 
231 	switch (level) {
232 	case SOL_SOCKET:
233 		return (LINUX_SOL_SOCKET);
234 	}
235 	return (level);
236 }
237 
238 static int
239 linux_to_bsd_ip_sockopt(int opt)
240 {
241 
242 	switch (opt) {
243 	case LINUX_IP_TOS:
244 		return (IP_TOS);
245 	case LINUX_IP_TTL:
246 		return (IP_TTL);
247 	case LINUX_IP_OPTIONS:
248 		return (IP_OPTIONS);
249 	case LINUX_IP_MULTICAST_IF:
250 		return (IP_MULTICAST_IF);
251 	case LINUX_IP_MULTICAST_TTL:
252 		return (IP_MULTICAST_TTL);
253 	case LINUX_IP_MULTICAST_LOOP:
254 		return (IP_MULTICAST_LOOP);
255 	case LINUX_IP_ADD_MEMBERSHIP:
256 		return (IP_ADD_MEMBERSHIP);
257 	case LINUX_IP_DROP_MEMBERSHIP:
258 		return (IP_DROP_MEMBERSHIP);
259 	case LINUX_IP_HDRINCL:
260 		return (IP_HDRINCL);
261 	}
262 	return (-1);
263 }
264 
265 static int
266 linux_to_bsd_so_sockopt(int opt)
267 {
268 
269 	switch (opt) {
270 	case LINUX_SO_DEBUG:
271 		return (SO_DEBUG);
272 	case LINUX_SO_REUSEADDR:
273 		return (SO_REUSEADDR);
274 	case LINUX_SO_TYPE:
275 		return (SO_TYPE);
276 	case LINUX_SO_ERROR:
277 		return (SO_ERROR);
278 	case LINUX_SO_DONTROUTE:
279 		return (SO_DONTROUTE);
280 	case LINUX_SO_BROADCAST:
281 		return (SO_BROADCAST);
282 	case LINUX_SO_SNDBUF:
283 		return (SO_SNDBUF);
284 	case LINUX_SO_RCVBUF:
285 		return (SO_RCVBUF);
286 	case LINUX_SO_KEEPALIVE:
287 		return (SO_KEEPALIVE);
288 	case LINUX_SO_OOBINLINE:
289 		return (SO_OOBINLINE);
290 	case LINUX_SO_LINGER:
291 		return (SO_LINGER);
292 	}
293 	return (-1);
294 }
295 
296 static int
297 linux_to_bsd_msg_flags(int flags)
298 {
299 	int ret_flags = 0;
300 
301 	if (flags & LINUX_MSG_OOB)
302 		ret_flags |= MSG_OOB;
303 	if (flags & LINUX_MSG_PEEK)
304 		ret_flags |= MSG_PEEK;
305 	if (flags & LINUX_MSG_DONTROUTE)
306 		ret_flags |= MSG_DONTROUTE;
307 	if (flags & LINUX_MSG_CTRUNC)
308 		ret_flags |= MSG_CTRUNC;
309 	if (flags & LINUX_MSG_TRUNC)
310 		ret_flags |= MSG_TRUNC;
311 	if (flags & LINUX_MSG_DONTWAIT)
312 		ret_flags |= MSG_DONTWAIT;
313 	if (flags & LINUX_MSG_EOR)
314 		ret_flags |= MSG_EOR;
315 	if (flags & LINUX_MSG_WAITALL)
316 		ret_flags |= MSG_WAITALL;
317 #if 0 /* not handled */
318 	if (flags & LINUX_MSG_PROXY)
319 		;
320 	if (flags & LINUX_MSG_FIN)
321 		;
322 	if (flags & LINUX_MSG_SYN)
323 		;
324 	if (flags & LINUX_MSG_CONFIRM)
325 		;
326 	if (flags & LINUX_MSG_RST)
327 		;
328 	if (flags & LINUX_MSG_ERRQUEUE)
329 		;
330 	if (flags & LINUX_MSG_NOSIGNAL)
331 		;
332 #endif
333 	return ret_flags;
334 }
335 
336 /*
337  * Allocate stackgap and put the converted sockaddr structure
338  * there, address on stackgap returned in sap.
339  */
340 static int
341 linux_sa_get(caddr_t *sgp, struct sockaddr **sap,
342 	     const struct osockaddr *osa, int *osalen)
343 {
344 	struct sockaddr *sa, *usa;
345 	int alloclen, error;
346 
347 	alloclen = *osalen;
348 	error = do_sa_get(&sa, osa, &alloclen, M_TEMP);
349 	if (error)
350 		return (error);
351 
352 	usa = (struct sockaddr *) stackgap_alloc(sgp, alloclen);
353 	if (!usa) {
354 		error = ENOMEM;
355 		goto out;
356 	}
357 
358 	if ((error = copyout(sa, usa, alloclen)))
359 		goto out;
360 
361 	*sap = usa;
362 	*osalen = alloclen;
363 
364 out:
365 	FREE(sa, M_TEMP);
366 	return (error);
367 }
368 
369 static int
370 linux_sa_put(struct osockaddr *osa)
371 {
372 	struct osockaddr sa;
373 	int error, bdom;
374 
375 	/*
376 	 * Only read/write the osockaddr family part, the rest is
377 	 * not changed.
378 	 */
379 	error = copyin(osa, &sa, sizeof(sa.sa_family));
380 	if (error)
381 		return (error);
382 
383 	bdom = bsd_to_linux_domain(sa.sa_family);
384 	if (bdom == -1)
385 		return (EINVAL);
386 
387 	sa.sa_family = bdom;
388 	error = copyout(&sa, osa, sizeof(sa.sa_family));
389 	if (error)
390 		return (error);
391 
392 	return (0);
393 }
394 
395 /* Return 0 if IP_HDRINCL is set for the given socket. */
396 static int
397 linux_check_hdrincl(struct thread *td, caddr_t *sg, int s)
398 {
399 	struct getsockopt_args /* {
400 		int s;
401 		int level;
402 		int name;
403 		caddr_t val;
404 		int *avalsize;
405 	} */ bsd_args;
406 	int error;
407 	caddr_t val, valsize;
408 	int size_val = sizeof val;
409 	int optval;
410 
411 	val = stackgap_alloc(sg, sizeof(int));
412 	valsize = stackgap_alloc(sg, sizeof(int));
413 
414 	if ((error = copyout(&size_val, valsize, sizeof(size_val))))
415 		return (error);
416 
417 	bsd_args.s = s;
418 	bsd_args.level = IPPROTO_IP;
419 	bsd_args.name = IP_HDRINCL;
420 	bsd_args.val = val;
421 	bsd_args.avalsize = (int *)valsize;
422 	if ((error = getsockopt(td, &bsd_args)))
423 		return (error);
424 
425 	if ((error = copyin(val, &optval, sizeof(optval))))
426 		return (error);
427 
428 	return (optval == 0);
429 }
430 
431 /*
432  * Updated sendto() when IP_HDRINCL is set:
433  * tweak endian-dependent fields in the IP packet.
434  */
435 static int
436 linux_sendto_hdrincl(struct thread *td, caddr_t *sg, struct sendto_args *bsd_args)
437 {
438 /*
439  * linux_ip_copysize defines how many bytes we should copy
440  * from the beginning of the IP packet before we customize it for BSD.
441  * It should include all the fields we modify (ip_len and ip_off)
442  * and be as small as possible to minimize copying overhead.
443  */
444 #define linux_ip_copysize	8
445 
446 	struct ip *packet;
447 	struct msghdr *msg;
448 	struct iovec *iov;
449 
450 	int error;
451 	struct  sendmsg_args /* {
452 		int s;
453 		caddr_t msg;
454 		int flags;
455 	} */ sendmsg_args;
456 
457 	/* Check the packet isn't too small before we mess with it */
458 	if (bsd_args->len < linux_ip_copysize)
459 		return (EINVAL);
460 
461 	/*
462 	 * Tweaking the user buffer in place would be bad manners.
463 	 * We create a corrected IP header with just the needed length,
464 	 * then use an iovec to glue it to the rest of the user packet
465 	 * when calling sendmsg().
466 	 */
467 	packet = (struct ip *)stackgap_alloc(sg, linux_ip_copysize);
468 	msg = (struct msghdr *)stackgap_alloc(sg, sizeof(*msg));
469 	iov = (struct iovec *)stackgap_alloc(sg, sizeof(*iov)*2);
470 
471 	/* Make a copy of the beginning of the packet to be sent */
472 	if ((error = copyin(bsd_args->buf, packet, linux_ip_copysize)))
473 		return (error);
474 
475 	/* Convert fields from Linux to BSD raw IP socket format */
476 	packet->ip_len = bsd_args->len;
477 	packet->ip_off = ntohs(packet->ip_off);
478 
479 	/* Prepare the msghdr and iovec structures describing the new packet */
480 	msg->msg_name = bsd_args->to;
481 	msg->msg_namelen = bsd_args->tolen;
482 	msg->msg_iov = iov;
483 	msg->msg_iovlen = 2;
484 	msg->msg_control = NULL;
485 	msg->msg_controllen = 0;
486 	msg->msg_flags = 0;
487 	iov[0].iov_base = (char *)packet;
488 	iov[0].iov_len = linux_ip_copysize;
489 	iov[1].iov_base = (char *)(bsd_args->buf) + linux_ip_copysize;
490 	iov[1].iov_len = bsd_args->len - linux_ip_copysize;
491 
492 	sendmsg_args.s = bsd_args->s;
493 	sendmsg_args.msg = (caddr_t)msg;
494 	sendmsg_args.flags = bsd_args->flags;
495 	return (sendmsg(td, &sendmsg_args));
496 }
497 
498 struct linux_socket_args {
499 	int domain;
500 	int type;
501 	int protocol;
502 };
503 
504 static int
505 linux_socket(struct thread *td, struct linux_socket_args *args)
506 {
507 	struct linux_socket_args linux_args;
508 	struct socket_args /* {
509 		int domain;
510 		int type;
511 		int protocol;
512 	} */ bsd_args;
513 	struct setsockopt_args /* {
514 		int s;
515 		int level;
516 		int name;
517 		caddr_t val;
518 		int valsize;
519 	} */ bsd_setsockopt_args;
520 	int error;
521 	int retval_socket;
522 
523 	if ((error = copyin(args, &linux_args, sizeof(linux_args))))
524 		return (error);
525 
526 	bsd_args.protocol = linux_args.protocol;
527 	bsd_args.type = linux_args.type;
528 	bsd_args.domain = linux_to_bsd_domain(linux_args.domain);
529 	if (bsd_args.domain == -1)
530 		return (EINVAL);
531 
532 	retval_socket = socket(td, &bsd_args);
533 	if (bsd_args.type == SOCK_RAW
534 	    && (bsd_args.protocol == IPPROTO_RAW || bsd_args.protocol == 0)
535 	    && bsd_args.domain == AF_INET
536 	    && retval_socket >= 0) {
537 		/* It's a raw IP socket: set the IP_HDRINCL option. */
538 		caddr_t sg;
539 		int *hdrincl;
540 
541 		sg = stackgap_init();
542 		hdrincl = (int *)stackgap_alloc(&sg, sizeof(*hdrincl));
543 		*hdrincl = 1;
544 		bsd_setsockopt_args.s = td->td_retval[0];
545 		bsd_setsockopt_args.level = IPPROTO_IP;
546 		bsd_setsockopt_args.name = IP_HDRINCL;
547 		bsd_setsockopt_args.val = (caddr_t)hdrincl;
548 		bsd_setsockopt_args.valsize = sizeof(*hdrincl);
549 		/* We ignore any error returned by setsockopt() */
550 		setsockopt(td, &bsd_setsockopt_args);
551 		/* Copy back the return value from socket() */
552 		td->td_retval[0] = bsd_setsockopt_args.s;
553 	}
554 #ifdef INET6
555 	/*
556 	 * Linux AF_INET6 socket has IPV6_V6ONLY setsockopt set to 0 by
557 	 * default and some apps depend on this. So, set V6ONLY to 0
558 	 * for Linux apps if the sysctl value is set to 1.
559 	 */
560 	if (bsd_args.domain == PF_INET6 && retval_socket >= 0
561 #ifndef KLD_MODULE
562 	    /*
563 	     * XXX: Avoid undefined symbol error with an IPv4 only
564 	     * kernel.
565 	     */
566 	    && ip6_v6only
567 #endif
568 	    ) {
569 		caddr_t sg;
570 		int *v6only;
571 
572 		sg = stackgap_init();
573 		v6only = (int *)stackgap_alloc(&sg, sizeof(*v6only));
574 		*v6only = 0;
575 		bsd_setsockopt_args.s = td->td_retval[0];
576 		bsd_setsockopt_args.level = IPPROTO_IPV6;
577 		bsd_setsockopt_args.name = IPV6_V6ONLY;
578 		bsd_setsockopt_args.val = (caddr_t)v6only;
579 		bsd_setsockopt_args.valsize = sizeof(*v6only);
580 		/* We ignore any error returned by setsockopt() */
581 		setsockopt(td, &bsd_setsockopt_args);
582 		/* Copy back the return value from socket() */
583 		td->td_retval[0] = bsd_setsockopt_args.s;
584 	}
585 #endif
586 
587 	return (retval_socket);
588 }
589 
590 struct linux_bind_args {
591 	int s;
592 	struct osockaddr *name;
593 	int namelen;
594 };
595 
596 static int
597 linux_bind(struct thread *td, struct linux_bind_args *args)
598 {
599 	struct linux_bind_args linux_args;
600 	struct sockaddr *sa;
601 	int error;
602 
603 	if ((error = copyin(args, &linux_args, sizeof(linux_args))))
604 		return (error);
605 
606 	error = linux_getsockaddr(&sa, linux_args.name, linux_args.namelen);
607 	if (error)
608 		return (error);
609 
610 	return (kern_bind(td, linux_args.s, sa));
611 }
612 
613 struct linux_connect_args {
614 	int s;
615 	struct osockaddr * name;
616 	int namelen;
617 };
618 int linux_connect(struct thread *, struct linux_connect_args *);
619 #endif /* !__alpha__*/
620 
621 int
622 linux_connect(struct thread *td, struct linux_connect_args *args)
623 {
624 	struct linux_connect_args linux_args;
625 	struct socket *so;
626 	struct sockaddr *sa;
627 	u_int fflag;
628 	int error;
629 
630 #ifdef __alpha__
631 	bcopy(args, &linux_args, sizeof(linux_args));
632 #else
633 	if ((error = copyin(args, &linux_args, sizeof(linux_args))))
634 		return (error);
635 #endif /* __alpha__ */
636 
637 	error = linux_getsockaddr(&sa, (struct osockaddr *)linux_args.name,
638 	    linux_args.namelen);
639 	if (error)
640 		return (error);
641 
642 	error = kern_connect(td, linux_args.s, sa);
643 	if (error != EISCONN)
644 		return (error);
645 
646 	/*
647 	 * Linux doesn't return EISCONN the first time it occurs,
648 	 * when on a non-blocking socket. Instead it returns the
649 	 * error getsockopt(SOL_SOCKET, SO_ERROR) would return on BSD.
650 	 */
651 	if ((error = fgetsock(td, linux_args.s, &so, &fflag)) != 0)
652 		return(error);
653 	error = EISCONN;
654 	if (fflag & FNONBLOCK) {
655 		if (so->so_emuldata == 0)
656 			error = so->so_error;
657 		so->so_emuldata = (void *)1;
658 	}
659 	fputsock(so);
660 	return (error);
661 }
662 
663 #ifndef __alpha__
664 
665 struct linux_listen_args {
666 	int s;
667 	int backlog;
668 };
669 
670 static int
671 linux_listen(struct thread *td, struct linux_listen_args *args)
672 {
673 	struct linux_listen_args linux_args;
674 	struct listen_args /* {
675 		int s;
676 		int backlog;
677 	} */ bsd_args;
678 	int error;
679 
680 	if ((error = copyin(args, &linux_args, sizeof(linux_args))))
681 		return (error);
682 
683 	bsd_args.s = linux_args.s;
684 	bsd_args.backlog = linux_args.backlog;
685 	return (listen(td, &bsd_args));
686 }
687 
688 struct linux_accept_args {
689 	int s;
690 	struct osockaddr *addr;
691 	int *namelen;
692 };
693 
694 static int
695 linux_accept(struct thread *td, struct linux_accept_args *args)
696 {
697 	struct linux_accept_args linux_args;
698 	struct accept_args /* {
699 		int s;
700 		caddr_t name;
701 		int *anamelen;
702 	} */ bsd_args;
703 	struct close_args /* {
704 		int     fd;
705 	} */ c_args;
706 	struct fcntl_args /* {
707 		int fd;
708 		int cmd;
709 		long arg;
710 	} */ f_args;
711 	int error;
712 
713 	if ((error = copyin(args, &linux_args, sizeof(linux_args))))
714 		return (error);
715 
716 	bsd_args.s = linux_args.s;
717 	bsd_args.name = (caddr_t)linux_args.addr;
718 	bsd_args.anamelen = linux_args.namelen;
719 	error = oaccept(td, &bsd_args);
720 	if (error)
721 		return (error);
722 	if (linux_args.addr) {
723 		error = linux_sa_put(linux_args.addr);
724 		if (error) {
725 			c_args.fd = td->td_retval[0];
726 			(void)close(td, &c_args);
727 			return (error);
728 		}
729 	}
730 
731 	/*
732 	 * linux appears not to copy flags from the parent socket to the
733 	 * accepted one, so we must clear the flags in the new descriptor.
734 	 * Ignore any errors, because we already have an open fd.
735 	 */
736 	f_args.fd = td->td_retval[0];
737 	f_args.cmd = F_SETFL;
738 	f_args.arg = 0;
739 	(void)fcntl(td, &f_args);
740 	td->td_retval[0] = f_args.fd;
741 	return (0);
742 }
743 
744 struct linux_getsockname_args {
745 	int s;
746 	struct osockaddr *addr;
747 	int *namelen;
748 };
749 
750 static int
751 linux_getsockname(struct thread *td, struct linux_getsockname_args *args)
752 {
753 	struct linux_getsockname_args linux_args;
754 	struct getsockname_args /* {
755 		int fdes;
756 		caddr_t asa;
757 		int *alen;
758 	} */ bsd_args;
759 	int error;
760 
761 	if ((error = copyin(args, &linux_args, sizeof(linux_args))))
762 		return (error);
763 
764 	bsd_args.fdes = linux_args.s;
765 	bsd_args.asa = (caddr_t) linux_args.addr;
766 	bsd_args.alen = linux_args.namelen;
767 	error = ogetsockname(td, &bsd_args);
768 	if (error)
769 		return (error);
770 	error = linux_sa_put(linux_args.addr);
771 	if (error)
772 		return (error);
773 	return (0);
774 }
775 
776 struct linux_getpeername_args {
777 	int s;
778 	struct osockaddr *addr;
779 	int *namelen;
780 };
781 
782 static int
783 linux_getpeername(struct thread *td, struct linux_getpeername_args *args)
784 {
785 	struct linux_getpeername_args linux_args;
786 	struct ogetpeername_args /* {
787 		int fdes;
788 		caddr_t asa;
789 		int *alen;
790 	} */ bsd_args;
791 	int error;
792 
793 	if ((error = copyin(args, &linux_args, sizeof(linux_args))))
794 		return (error);
795 
796 	bsd_args.fdes = linux_args.s;
797 	bsd_args.asa = (caddr_t) linux_args.addr;
798 	bsd_args.alen = linux_args.namelen;
799 	error = ogetpeername(td, &bsd_args);
800 	if (error)
801 		return (error);
802 	error = linux_sa_put(linux_args.addr);
803 	if (error)
804 		return (error);
805 	return (0);
806 }
807 
808 struct linux_socketpair_args {
809 	int domain;
810 	int type;
811 	int protocol;
812 	int *rsv;
813 };
814 
815 static int
816 linux_socketpair(struct thread *td, struct linux_socketpair_args *args)
817 {
818 	struct linux_socketpair_args linux_args;
819 	struct socketpair_args /* {
820 		int domain;
821 		int type;
822 		int protocol;
823 		int *rsv;
824 	} */ bsd_args;
825 	int error;
826 
827 	if ((error = copyin(args, &linux_args, sizeof(linux_args))))
828 		return (error);
829 
830 	bsd_args.domain = linux_to_bsd_domain(linux_args.domain);
831 	if (bsd_args.domain == -1)
832 		return (EINVAL);
833 
834 	bsd_args.type = linux_args.type;
835 	bsd_args.protocol = linux_args.protocol;
836 	bsd_args.rsv = linux_args.rsv;
837 	return (socketpair(td, &bsd_args));
838 }
839 
840 struct linux_send_args {
841 	int s;
842 	void *msg;
843 	int len;
844 	int flags;
845 };
846 
847 static int
848 linux_send(struct thread *td, struct linux_send_args *args)
849 {
850 	struct linux_send_args linux_args;
851 	struct osend_args /* {
852 		int s;
853 		caddr_t buf;
854 		int len;
855 		int flags;
856 	} */ bsd_args;
857 	int error;
858 
859 	if ((error = copyin(args, &linux_args, sizeof(linux_args))))
860 		return (error);
861 
862 	bsd_args.s = linux_args.s;
863 	bsd_args.buf = linux_args.msg;
864 	bsd_args.len = linux_args.len;
865 	bsd_args.flags = linux_args.flags;
866 	return (osend(td, &bsd_args));
867 }
868 
869 struct linux_recv_args {
870 	int s;
871 	void *msg;
872 	int len;
873 	int flags;
874 };
875 
876 static int
877 linux_recv(struct thread *td, struct linux_recv_args *args)
878 {
879 	struct linux_recv_args linux_args;
880 	struct orecv_args /* {
881 		int s;
882 		caddr_t buf;
883 		int len;
884 		int flags;
885 	} */ bsd_args;
886 	int error;
887 
888 	if ((error = copyin(args, &linux_args, sizeof(linux_args))))
889 		return (error);
890 
891 	bsd_args.s = linux_args.s;
892 	bsd_args.buf = linux_args.msg;
893 	bsd_args.len = linux_args.len;
894 	bsd_args.flags = linux_args.flags;
895 	return (orecv(td, &bsd_args));
896 }
897 
898 struct linux_sendto_args {
899 	int s;
900 	void *msg;
901 	int len;
902 	int flags;
903 	caddr_t to;
904 	int tolen;
905 };
906 
907 static int
908 linux_sendto(struct thread *td, struct linux_sendto_args *args)
909 {
910 	struct linux_sendto_args linux_args;
911 	struct sendto_args /* {
912 		int s;
913 		caddr_t buf;
914 		size_t len;
915 		int flags;
916 		caddr_t to;
917 		int tolen;
918 	} */ bsd_args;
919 	caddr_t sg = stackgap_init();
920 	struct sockaddr *to;
921 	int tolen, error;
922 
923 	if ((error = copyin(args, &linux_args, sizeof(linux_args))))
924 		return (error);
925 
926 	tolen = linux_args.tolen;
927 	if (linux_args.to) {
928 		error = linux_sa_get(&sg, &to,
929 		    (struct osockaddr *) linux_args.to, &tolen);
930 		if (error)
931 			return (error);
932 	} else
933 		to = NULL;
934 
935 	bsd_args.s = linux_args.s;
936 	bsd_args.buf = linux_args.msg;
937 	bsd_args.len = linux_args.len;
938 	bsd_args.flags = linux_args.flags;
939 	bsd_args.to = (caddr_t) to;
940 	bsd_args.tolen = (unsigned int) tolen;
941 
942 	if (linux_check_hdrincl(td, &sg, linux_args.s) == 0)
943 		/* IP_HDRINCL set, tweak the packet before sending */
944 		return (linux_sendto_hdrincl(td, &sg, &bsd_args));
945 
946 	return (sendto(td, &bsd_args));
947 }
948 
949 struct linux_recvfrom_args {
950 	int s;
951 	void *buf;
952 	int len;
953 	int flags;
954 	caddr_t from;
955 	int *fromlen;
956 };
957 
958 static int
959 linux_recvfrom(struct thread *td, struct linux_recvfrom_args *args)
960 {
961 	struct linux_recvfrom_args linux_args;
962 	struct recvfrom_args /* {
963 		int s;
964 		caddr_t buf;
965 		size_t len;
966 		int flags;
967 		caddr_t from;
968 		int *fromlenaddr;
969 	} */ bsd_args;
970 	int error;
971 
972 	if ((error = copyin(args, &linux_args, sizeof(linux_args))))
973 		return (error);
974 
975 	bsd_args.s = linux_args.s;
976 	bsd_args.buf = linux_args.buf;
977 	bsd_args.len = linux_args.len;
978 	bsd_args.flags = linux_to_bsd_msg_flags(linux_args.flags);
979 	bsd_args.from = linux_args.from;
980 	bsd_args.fromlenaddr = linux_args.fromlen;
981 	error = orecvfrom(td, &bsd_args);
982 	if (error)
983 		return (error);
984 	if (linux_args.from) {
985 		error = linux_sa_put((struct osockaddr *) linux_args.from);
986 		if (error)
987 			return (error);
988 	}
989 	return (0);
990 }
991 
992 struct linux_sendmsg_args {
993 	int s;
994 	const struct msghdr *msg;
995 	int flags;
996 };
997 
998 static int
999 linux_sendmsg(struct thread *td, struct linux_sendmsg_args *args)
1000 {
1001 	struct linux_sendmsg_args linux_args;
1002 	struct sendmsg_args /* {
1003 		int s;
1004 		const struct msghdr *msg;
1005 		int flags;
1006 	} */ bsd_args;
1007 	struct msghdr msg;
1008 	struct msghdr *nmsg = NULL;
1009 	struct cmsghdr *cmsg;
1010 	int error;
1011 	caddr_t sg;
1012 
1013 	if ((error = copyin(args, &linux_args, sizeof(linux_args))))
1014 		return (error);
1015 
1016 	error = copyin(linux_args.msg, &msg, sizeof(msg));
1017 	if (error)
1018 		return (error);
1019 
1020 	sg = stackgap_init();
1021 	nmsg = (struct msghdr *)stackgap_alloc(&sg, sizeof(struct msghdr));
1022 	if (nmsg == NULL)
1023 		return (ENOMEM);
1024 
1025 	bcopy(&msg, nmsg, sizeof(struct msghdr));
1026 
1027 	if (msg.msg_name != NULL) {
1028 		struct sockaddr *sa;
1029 
1030 		error = linux_sa_get(&sg, &sa,
1031 		    (struct osockaddr *) msg.msg_name, &msg.msg_namelen);
1032 		if (error)
1033 			return (error);
1034 
1035 		nmsg->msg_name = sa;
1036 	}
1037 
1038 	if (msg.msg_control != NULL) {
1039 		nmsg->msg_control = (struct cmsghdr *)stackgap_alloc(&sg,
1040 		    msg.msg_controllen);
1041 		if (nmsg->msg_control == NULL)
1042 			return (ENOMEM);
1043 
1044 		bcopy(msg.msg_control, nmsg->msg_control, msg.msg_controllen);
1045 		cmsg = (struct cmsghdr*)nmsg->msg_control;
1046 
1047 		cmsg->cmsg_level = linux_to_bsd_sockopt_level(cmsg->cmsg_level);
1048 	}
1049 
1050 	bsd_args.s = linux_args.s;
1051 	bsd_args.msg = (caddr_t)nmsg;
1052 	bsd_args.flags = linux_to_bsd_msg_flags(linux_args.flags);
1053 	return (sendmsg(td, &bsd_args));
1054 }
1055 
1056 struct linux_recvmsg_args {
1057 	int s;
1058 	struct msghdr *msg;
1059 	int flags;
1060 };
1061 
1062 static int
1063 linux_recvmsg(struct thread *td, struct linux_recvmsg_args *args)
1064 {
1065 	struct linux_recvmsg_args linux_args;
1066 	struct recvmsg_args /* {
1067 		int	s;
1068 		struct	msghdr *msg;
1069 		int	flags;
1070 	} */ bsd_args;
1071 	struct msghdr msg;
1072 	struct cmsghdr *cmsg;
1073 	int error;
1074 
1075 	if ((error = copyin(args, &linux_args, sizeof(linux_args))))
1076 		return (error);
1077 
1078 	bsd_args.s = linux_args.s;
1079 	bsd_args.msg = linux_args.msg;
1080 	bsd_args.flags = linux_to_bsd_msg_flags(linux_args.flags);
1081 	error = recvmsg(td, &bsd_args);
1082 	if (error)
1083 		return (error);
1084 
1085 	if (bsd_args.msg->msg_control != NULL) {
1086 		cmsg = (struct cmsghdr*)bsd_args.msg->msg_control;
1087 		cmsg->cmsg_level = bsd_to_linux_sockopt_level(cmsg->cmsg_level);
1088 	}
1089 
1090 	error = copyin(linux_args.msg, &msg, sizeof(msg));
1091 	if (error)
1092 		return (error);
1093 	if (msg.msg_name && msg.msg_namelen > 2)
1094 		error = linux_sa_put(msg.msg_name);
1095 	return (error);
1096 }
1097 
1098 struct linux_shutdown_args {
1099 	int s;
1100 	int how;
1101 };
1102 
1103 static int
1104 linux_shutdown(struct thread *td, struct linux_shutdown_args *args)
1105 {
1106 	struct linux_shutdown_args linux_args;
1107 	struct shutdown_args /* {
1108 		int s;
1109 		int how;
1110 	} */ bsd_args;
1111 	int error;
1112 
1113 	if ((error = copyin(args, &linux_args, sizeof(linux_args))))
1114 		return (error);
1115 
1116 	bsd_args.s = linux_args.s;
1117 	bsd_args.how = linux_args.how;
1118 	return (shutdown(td, &bsd_args));
1119 }
1120 
1121 struct linux_setsockopt_args {
1122 	int s;
1123 	int level;
1124 	int optname;
1125 	void *optval;
1126 	int optlen;
1127 };
1128 
1129 static int
1130 linux_setsockopt(struct thread *td, struct linux_setsockopt_args *args)
1131 {
1132 	struct linux_setsockopt_args linux_args;
1133 	struct setsockopt_args /* {
1134 		int s;
1135 		int level;
1136 		int name;
1137 		caddr_t val;
1138 		int valsize;
1139 	} */ bsd_args;
1140 	int error, name;
1141 
1142 	if ((error = copyin(args, &linux_args, sizeof(linux_args))))
1143 		return (error);
1144 
1145 	bsd_args.s = linux_args.s;
1146 	bsd_args.level = linux_to_bsd_sockopt_level(linux_args.level);
1147 	switch (bsd_args.level) {
1148 	case SOL_SOCKET:
1149 		name = linux_to_bsd_so_sockopt(linux_args.optname);
1150 		break;
1151 	case IPPROTO_IP:
1152 		name = linux_to_bsd_ip_sockopt(linux_args.optname);
1153 		break;
1154 	case IPPROTO_TCP:
1155 		/* Linux TCP option values match BSD's */
1156 		name = linux_args.optname;
1157 		break;
1158 	default:
1159 		name = -1;
1160 		break;
1161 	}
1162 	if (name == -1)
1163 		return (EINVAL);
1164 
1165 	bsd_args.name = name;
1166 	bsd_args.val = linux_args.optval;
1167 	bsd_args.valsize = linux_args.optlen;
1168 	return (setsockopt(td, &bsd_args));
1169 }
1170 
1171 struct linux_getsockopt_args {
1172 	int s;
1173 	int level;
1174 	int optname;
1175 	void *optval;
1176 	int *optlen;
1177 };
1178 
1179 static int
1180 linux_getsockopt(struct thread *td, struct linux_getsockopt_args *args)
1181 {
1182 	struct linux_getsockopt_args linux_args;
1183 	struct getsockopt_args /* {
1184 		int s;
1185 		int level;
1186 		int name;
1187 		caddr_t val;
1188 		int *avalsize;
1189 	} */ bsd_args;
1190 	int error, name;
1191 
1192 	if ((error = copyin(args, &linux_args, sizeof(linux_args))))
1193 		return (error);
1194 
1195 	bsd_args.s = linux_args.s;
1196 	bsd_args.level = linux_to_bsd_sockopt_level(linux_args.level);
1197 	switch (bsd_args.level) {
1198 	case SOL_SOCKET:
1199 		name = linux_to_bsd_so_sockopt(linux_args.optname);
1200 		break;
1201 	case IPPROTO_IP:
1202 		name = linux_to_bsd_ip_sockopt(linux_args.optname);
1203 		break;
1204 	case IPPROTO_TCP:
1205 		/* Linux TCP option values match BSD's */
1206 		name = linux_args.optname;
1207 		break;
1208 	default:
1209 		name = -1;
1210 		break;
1211 	}
1212 	if (name == -1)
1213 		return (EINVAL);
1214 
1215 	bsd_args.name = name;
1216 	bsd_args.val = linux_args.optval;
1217 	bsd_args.avalsize = linux_args.optlen;
1218 	return (getsockopt(td, &bsd_args));
1219 }
1220 
1221 int
1222 linux_socketcall(struct thread *td, struct linux_socketcall_args *args)
1223 {
1224 	void *arg = (void *)args->args;
1225 
1226 	switch (args->what) {
1227 	case LINUX_SOCKET:
1228 		return (linux_socket(td, arg));
1229 	case LINUX_BIND:
1230 		return (linux_bind(td, arg));
1231 	case LINUX_CONNECT:
1232 		return (linux_connect(td, arg));
1233 	case LINUX_LISTEN:
1234 		return (linux_listen(td, arg));
1235 	case LINUX_ACCEPT:
1236 		return (linux_accept(td, arg));
1237 	case LINUX_GETSOCKNAME:
1238 		return (linux_getsockname(td, arg));
1239 	case LINUX_GETPEERNAME:
1240 		return (linux_getpeername(td, arg));
1241 	case LINUX_SOCKETPAIR:
1242 		return (linux_socketpair(td, arg));
1243 	case LINUX_SEND:
1244 		return (linux_send(td, arg));
1245 	case LINUX_RECV:
1246 		return (linux_recv(td, arg));
1247 	case LINUX_SENDTO:
1248 		return (linux_sendto(td, arg));
1249 	case LINUX_RECVFROM:
1250 		return (linux_recvfrom(td, arg));
1251 	case LINUX_SHUTDOWN:
1252 		return (linux_shutdown(td, arg));
1253 	case LINUX_SETSOCKOPT:
1254 		return (linux_setsockopt(td, arg));
1255 	case LINUX_GETSOCKOPT:
1256 		return (linux_getsockopt(td, arg));
1257 	case LINUX_SENDMSG:
1258 		return (linux_sendmsg(td, arg));
1259 	case LINUX_RECVMSG:
1260 		return (linux_recvmsg(td, arg));
1261 	}
1262 
1263 	uprintf("LINUX: 'socket' typ=%d not implemented\n", args->what);
1264 	return (ENOSYS);
1265 }
1266 #endif	/*!__alpha__*/
1267