xref: /freebsd-13-stable/sys/compat/linux/linux.c (revision db4429d00f0d95a1532f8707f8b828a744586dc7)
1 /*-
2  * Copyright (c) 2015 Dmitry Chagin <dchagin@FreeBSD.org>
3  *
4  * Redistribution and use in source and binary forms, with or without
5  * modification, are permitted provided that the following conditions
6  * are met:
7  * 1. Redistributions of source code must retain the above copyright
8  *    notice, this list of conditions and the following disclaimer.
9  * 2. Redistributions in binary form must reproduce the above copyright
10  *    notice, this list of conditions and the following disclaimer in the
11  *    documentation and/or other materials provided with the distribution.
12  *
13  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
14  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
15  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
16  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
17  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
18  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
19  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
20  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
21  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
22  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
23  * SUCH DAMAGE.
24  */
25 
26 #include <sys/cdefs.h>
27 #include "opt_inet6.h"
28 
29 #include <sys/param.h>
30 #include <sys/conf.h>
31 #include <sys/ctype.h>
32 #include <sys/file.h>
33 #include <sys/filedesc.h>
34 #include <sys/jail.h>
35 #include <sys/lock.h>
36 #include <sys/malloc.h>
37 #include <sys/poll.h>
38 #include <sys/proc.h>
39 #include <sys/signalvar.h>
40 #include <sys/socket.h>
41 #include <sys/socketvar.h>
42 
43 #include <net/if.h>
44 #include <net/if_var.h>
45 #include <net/if_dl.h>
46 #include <net/if_types.h>
47 #include <netlink/netlink.h>
48 
49 #include <sys/un.h>
50 #include <netinet/in.h>
51 
52 #include <compat/linux/linux.h>
53 #include <compat/linux/linux_common.h>
54 #include <compat/linux/linux_mib.h>
55 #include <compat/linux/linux_util.h>
56 
57 CTASSERT(LINUX_IFNAMSIZ == IFNAMSIZ);
58 
59 static bool use_real_ifnames = false;
60 SYSCTL_BOOL(_compat_linux, OID_AUTO, use_real_ifnames, CTLFLAG_RWTUN,
61     &use_real_ifnames, 0,
62     "Use FreeBSD interface names instead of generating ethN aliases");
63 
64 static int bsd_to_linux_sigtbl[LINUX_SIGTBLSZ] = {
65 	LINUX_SIGHUP,	/* SIGHUP */
66 	LINUX_SIGINT,	/* SIGINT */
67 	LINUX_SIGQUIT,	/* SIGQUIT */
68 	LINUX_SIGILL,	/* SIGILL */
69 	LINUX_SIGTRAP,	/* SIGTRAP */
70 	LINUX_SIGABRT,	/* SIGABRT */
71 	0,		/* SIGEMT */
72 	LINUX_SIGFPE,	/* SIGFPE */
73 	LINUX_SIGKILL,	/* SIGKILL */
74 	LINUX_SIGBUS,	/* SIGBUS */
75 	LINUX_SIGSEGV,	/* SIGSEGV */
76 	LINUX_SIGSYS,	/* SIGSYS */
77 	LINUX_SIGPIPE,	/* SIGPIPE */
78 	LINUX_SIGALRM,	/* SIGALRM */
79 	LINUX_SIGTERM,	/* SIGTERM */
80 	LINUX_SIGURG,	/* SIGURG */
81 	LINUX_SIGSTOP,	/* SIGSTOP */
82 	LINUX_SIGTSTP,	/* SIGTSTP */
83 	LINUX_SIGCONT,	/* SIGCONT */
84 	LINUX_SIGCHLD,	/* SIGCHLD */
85 	LINUX_SIGTTIN,	/* SIGTTIN */
86 	LINUX_SIGTTOU,	/* SIGTTOU */
87 	LINUX_SIGIO,	/* SIGIO */
88 	LINUX_SIGXCPU,	/* SIGXCPU */
89 	LINUX_SIGXFSZ,	/* SIGXFSZ */
90 	LINUX_SIGVTALRM,/* SIGVTALRM */
91 	LINUX_SIGPROF,	/* SIGPROF */
92 	LINUX_SIGWINCH,	/* SIGWINCH */
93 	0,		/* SIGINFO */
94 	LINUX_SIGUSR1,	/* SIGUSR1 */
95 	LINUX_SIGUSR2	/* SIGUSR2 */
96 };
97 
98 #define	LINUX_SIGPWREMU	(SIGRTMIN + (LINUX_SIGRTMAX - LINUX_SIGRTMIN) + 1)
99 
100 static int linux_to_bsd_sigtbl[LINUX_SIGTBLSZ] = {
101 	SIGHUP,		/* LINUX_SIGHUP */
102 	SIGINT,		/* LINUX_SIGINT */
103 	SIGQUIT,	/* LINUX_SIGQUIT */
104 	SIGILL,		/* LINUX_SIGILL */
105 	SIGTRAP,	/* LINUX_SIGTRAP */
106 	SIGABRT,	/* LINUX_SIGABRT */
107 	SIGBUS,		/* LINUX_SIGBUS */
108 	SIGFPE,		/* LINUX_SIGFPE */
109 	SIGKILL,	/* LINUX_SIGKILL */
110 	SIGUSR1,	/* LINUX_SIGUSR1 */
111 	SIGSEGV,	/* LINUX_SIGSEGV */
112 	SIGUSR2,	/* LINUX_SIGUSR2 */
113 	SIGPIPE,	/* LINUX_SIGPIPE */
114 	SIGALRM,	/* LINUX_SIGALRM */
115 	SIGTERM,	/* LINUX_SIGTERM */
116 	SIGBUS,		/* LINUX_SIGSTKFLT */
117 	SIGCHLD,	/* LINUX_SIGCHLD */
118 	SIGCONT,	/* LINUX_SIGCONT */
119 	SIGSTOP,	/* LINUX_SIGSTOP */
120 	SIGTSTP,	/* LINUX_SIGTSTP */
121 	SIGTTIN,	/* LINUX_SIGTTIN */
122 	SIGTTOU,	/* LINUX_SIGTTOU */
123 	SIGURG,		/* LINUX_SIGURG */
124 	SIGXCPU,	/* LINUX_SIGXCPU */
125 	SIGXFSZ,	/* LINUX_SIGXFSZ */
126 	SIGVTALRM,	/* LINUX_SIGVTALARM */
127 	SIGPROF,	/* LINUX_SIGPROF */
128 	SIGWINCH,	/* LINUX_SIGWINCH */
129 	SIGIO,		/* LINUX_SIGIO */
130 	/*
131 	 * FreeBSD does not have SIGPWR signal, map Linux SIGPWR signal
132 	 * to the first unused FreeBSD signal number. Since Linux supports
133 	 * signals from 1 to 64 we are ok here as our SIGRTMIN = 65.
134 	 */
135 	LINUX_SIGPWREMU,/* LINUX_SIGPWR */
136 	SIGSYS		/* LINUX_SIGSYS */
137 };
138 
139 static struct cdev *dev_shm_cdev;
140 static struct cdevsw dev_shm_cdevsw = {
141      .d_version = D_VERSION,
142      .d_name    = "dev_shm",
143 };
144 
145 /*
146  * Map Linux RT signals to the FreeBSD RT signals.
147  */
148 static inline int
linux_to_bsd_rt_signal(int sig)149 linux_to_bsd_rt_signal(int sig)
150 {
151 
152 	return (SIGRTMIN + sig - LINUX_SIGRTMIN);
153 }
154 
155 static inline int
bsd_to_linux_rt_signal(int sig)156 bsd_to_linux_rt_signal(int sig)
157 {
158 
159 	return (sig - SIGRTMIN + LINUX_SIGRTMIN);
160 }
161 
162 int
linux_to_bsd_signal(int sig)163 linux_to_bsd_signal(int sig)
164 {
165 
166 	KASSERT(sig > 0 && sig <= LINUX_SIGRTMAX, ("invalid Linux signal %d\n", sig));
167 
168 	if (sig < LINUX_SIGRTMIN)
169 		return (linux_to_bsd_sigtbl[_SIG_IDX(sig)]);
170 
171 	return (linux_to_bsd_rt_signal(sig));
172 }
173 
174 int
bsd_to_linux_signal(int sig)175 bsd_to_linux_signal(int sig)
176 {
177 
178 	if (sig <= LINUX_SIGTBLSZ)
179 		return (bsd_to_linux_sigtbl[_SIG_IDX(sig)]);
180 	if (sig == LINUX_SIGPWREMU)
181 		return (LINUX_SIGPWR);
182 
183 	return (bsd_to_linux_rt_signal(sig));
184 }
185 
186 int
linux_to_bsd_sigaltstack(int lsa)187 linux_to_bsd_sigaltstack(int lsa)
188 {
189 	int bsa = 0;
190 
191 	if (lsa & LINUX_SS_DISABLE)
192 		bsa |= SS_DISABLE;
193 	/*
194 	 * Linux ignores SS_ONSTACK flag for ss
195 	 * parameter while FreeBSD prohibits it.
196 	 */
197 	return (bsa);
198 }
199 
200 int
bsd_to_linux_sigaltstack(int bsa)201 bsd_to_linux_sigaltstack(int bsa)
202 {
203 	int lsa = 0;
204 
205 	if (bsa & SS_DISABLE)
206 		lsa |= LINUX_SS_DISABLE;
207 	if (bsa & SS_ONSTACK)
208 		lsa |= LINUX_SS_ONSTACK;
209 	return (lsa);
210 }
211 
212 void
linux_to_bsd_sigset(l_sigset_t * lss,sigset_t * bss)213 linux_to_bsd_sigset(l_sigset_t *lss, sigset_t *bss)
214 {
215 	int b, l;
216 
217 	SIGEMPTYSET(*bss);
218 	for (l = 1; l <= LINUX_SIGRTMAX; l++) {
219 		if (LINUX_SIGISMEMBER(*lss, l)) {
220 			b = linux_to_bsd_signal(l);
221 			if (b)
222 				SIGADDSET(*bss, b);
223 		}
224 	}
225 }
226 
227 void
bsd_to_linux_sigset(sigset_t * bss,l_sigset_t * lss)228 bsd_to_linux_sigset(sigset_t *bss, l_sigset_t *lss)
229 {
230 	int b, l;
231 
232 	LINUX_SIGEMPTYSET(*lss);
233 	for (b = 1; b <= SIGRTMAX; b++) {
234 		if (SIGISMEMBER(*bss, b)) {
235 			l = bsd_to_linux_signal(b);
236 			if (l)
237 				LINUX_SIGADDSET(*lss, l);
238 		}
239 	}
240 }
241 
242 /*
243  * Translate a FreeBSD interface name to a Linux interface name
244  * by interface name, and return the number of bytes copied to lxname.
245  */
246 int
ifname_bsd_to_linux_name(const char * bsdname,char * lxname,size_t len)247 ifname_bsd_to_linux_name(const char *bsdname, char *lxname, size_t len)
248 {
249 	struct epoch_tracker et;
250 	struct ifnet *ifp;
251 	int ret;
252 
253 	CURVNET_ASSERT_SET();
254 
255 	ret = 0;
256 	NET_EPOCH_ENTER(et);
257 	ifp = ifunit(bsdname);
258 	if (ifp != NULL)
259 		ret = ifname_bsd_to_linux_ifp(ifp, lxname, len);
260 	NET_EPOCH_EXIT(et);
261 	return (ret);
262 }
263 
264 /*
265  * Translate a FreeBSD interface name to a Linux interface name
266  * by interface index, and return the number of bytes copied to lxname.
267  */
268 int
ifname_bsd_to_linux_idx(u_int idx,char * lxname,size_t len)269 ifname_bsd_to_linux_idx(u_int idx, char *lxname, size_t len)
270 {
271 	struct epoch_tracker et;
272 	struct ifnet *ifp;
273 	int ret;
274 
275 	ret = 0;
276 	CURVNET_SET(TD_TO_VNET(curthread));
277 	NET_EPOCH_ENTER(et);
278 	ifp = ifnet_byindex(idx);
279 	if (ifp != NULL)
280 		ret = ifname_bsd_to_linux_ifp(ifp, lxname, len);
281 	NET_EPOCH_EXIT(et);
282 	CURVNET_RESTORE();
283 	return (ret);
284 }
285 
286 /*
287  * Translate a FreeBSD interface name to a Linux interface name,
288  * and return the number of bytes copied to lxname.
289  */
290 int
ifname_bsd_to_linux_ifp(struct ifnet * ifp,char * lxname,size_t len)291 ifname_bsd_to_linux_ifp(struct ifnet *ifp, char *lxname, size_t len)
292 {
293 	struct ifnet *ifscan;
294 	int unit;
295 
296 	NET_EPOCH_ASSERT();
297 
298 	/*
299 	 * Linux loopback interface name is lo (not lo0),
300 	 * we translate lo to lo0, loX to loX.
301 	 */
302 	if (IFP_IS_LOOP(ifp) && strncmp(ifp->if_xname, "lo0", IFNAMSIZ) == 0)
303 		return (strlcpy(lxname, "lo", len));
304 
305 	/* Short-circuit non ethernet interfaces. */
306 	if (!IFP_IS_ETH(ifp) || linux_use_real_ifname(ifp))
307 		return (strlcpy(lxname, ifp->if_xname, len));
308 
309 	/* Determine the (relative) unit number for ethernet interfaces. */
310 	unit = 0;
311 	CK_STAILQ_FOREACH(ifscan, &V_ifnet, if_link) {
312 		if (ifscan == ifp)
313 			return (snprintf(lxname, len, "eth%d", unit));
314 		if (IFP_IS_ETH(ifscan))
315 			unit++;
316 	}
317 	return (0);
318 }
319 
320 /*
321  * Translate a Linux interface name to a FreeBSD interface name,
322  * and return the associated ifnet structure
323  * bsdname and lxname need to be least IFNAMSIZ bytes long, but
324  * can point to the same buffer.
325  */
326 struct ifnet *
ifname_linux_to_bsd(struct thread * td,const char * lxname,char * bsdname)327 ifname_linux_to_bsd(struct thread *td, const char *lxname, char *bsdname)
328 {
329 	struct ifnet *ifp;
330 	int len, unit;
331 	char *ep;
332 	int index;
333 	bool is_eth, is_lo;
334 
335 	for (len = 0; len < LINUX_IFNAMSIZ; ++len)
336 		if (!isalpha(lxname[len]) || lxname[len] == '\0')
337 			break;
338 	if (len == 0 || len == LINUX_IFNAMSIZ)
339 		return (NULL);
340 	/*
341 	 * Linux loopback interface name is lo (not lo0),
342 	 * we translate lo to lo0, loX to loX.
343 	 */
344 	is_lo = (len == 2 && strncmp(lxname, "lo", LINUX_IFNAMSIZ) == 0);
345 	unit = (int)strtoul(lxname + len, &ep, 10);
346 	if ((ep == NULL || ep == lxname + len || ep >= lxname + LINUX_IFNAMSIZ) &&
347 	    is_lo == 0)
348 		return (NULL);
349 	index = 0;
350 	is_eth = (len == 3 && strncmp(lxname, "eth", len) == 0);
351 
352 	CURVNET_SET(TD_TO_VNET(td));
353 	IFNET_RLOCK();
354 	CK_STAILQ_FOREACH(ifp, &V_ifnet, if_link) {
355 		/*
356 		 * Allow Linux programs to use FreeBSD names. Don't presume
357 		 * we never have an interface named "eth", so don't make
358 		 * the test optional based on is_eth.
359 		 */
360 		if (strncmp(ifp->if_xname, lxname, LINUX_IFNAMSIZ) == 0)
361 			break;
362 		if (is_eth && IFP_IS_ETH(ifp) && unit == index++)
363 			break;
364 		if (is_lo && IFP_IS_LOOP(ifp))
365 			break;
366 	}
367 	IFNET_RUNLOCK();
368 	CURVNET_RESTORE();
369 	if (ifp != NULL && bsdname != NULL)
370 		strlcpy(bsdname, ifp->if_xname, IFNAMSIZ);
371 	return (ifp);
372 }
373 
374 void
linux_ifflags(struct ifnet * ifp,short * flags)375 linux_ifflags(struct ifnet *ifp, short *flags)
376 {
377 	unsigned short fl;
378 
379 	fl = (ifp->if_flags | ifp->if_drv_flags) & 0xffff;
380 	*flags = 0;
381 	if (fl & IFF_UP)
382 		*flags |= LINUX_IFF_UP;
383 	if (fl & IFF_BROADCAST)
384 		*flags |= LINUX_IFF_BROADCAST;
385 	if (fl & IFF_DEBUG)
386 		*flags |= LINUX_IFF_DEBUG;
387 	if (fl & IFF_LOOPBACK)
388 		*flags |= LINUX_IFF_LOOPBACK;
389 	if (fl & IFF_POINTOPOINT)
390 		*flags |= LINUX_IFF_POINTOPOINT;
391 	if (fl & IFF_DRV_RUNNING)
392 		*flags |= LINUX_IFF_RUNNING;
393 	if (fl & IFF_NOARP)
394 		*flags |= LINUX_IFF_NOARP;
395 	if (fl & IFF_PROMISC)
396 		*flags |= LINUX_IFF_PROMISC;
397 	if (fl & IFF_ALLMULTI)
398 		*flags |= LINUX_IFF_ALLMULTI;
399 	if (fl & IFF_MULTICAST)
400 		*flags |= LINUX_IFF_MULTICAST;
401 }
402 
403 int
linux_ifhwaddr(struct ifnet * ifp,struct l_sockaddr * lsa)404 linux_ifhwaddr(struct ifnet *ifp, struct l_sockaddr *lsa)
405 {
406 	struct ifaddr *ifa;
407 	struct sockaddr_dl *sdl;
408 
409 	if (IFP_IS_LOOP(ifp)) {
410 		bzero(lsa, sizeof(*lsa));
411 		lsa->sa_family = LINUX_ARPHRD_LOOPBACK;
412 		return (0);
413 	}
414 
415 	if (!IFP_IS_ETH(ifp))
416 		return (ENOENT);
417 
418 	CK_STAILQ_FOREACH(ifa, &ifp->if_addrhead, ifa_link) {
419 		sdl = (struct sockaddr_dl*)ifa->ifa_addr;
420 		if (sdl != NULL && (sdl->sdl_family == AF_LINK) &&
421 		    (sdl->sdl_type == IFT_ETHER)) {
422 			bzero(lsa, sizeof(*lsa));
423 			lsa->sa_family = LINUX_ARPHRD_ETHER;
424 			bcopy(LLADDR(sdl), lsa->sa_data, LINUX_IFHWADDRLEN);
425 			return (0);
426 		}
427 	}
428 
429 	return (ENOENT);
430 }
431 
432 int
linux_to_bsd_domain(int domain)433 linux_to_bsd_domain(int domain)
434 {
435 
436 	switch (domain) {
437 	case LINUX_AF_UNSPEC:
438 		return (AF_UNSPEC);
439 	case LINUX_AF_UNIX:
440 		return (AF_LOCAL);
441 	case LINUX_AF_INET:
442 		return (AF_INET);
443 	case LINUX_AF_INET6:
444 		return (AF_INET6);
445 	case LINUX_AF_AX25:
446 		return (AF_CCITT);
447 	case LINUX_AF_IPX:
448 		return (AF_IPX);
449 	case LINUX_AF_APPLETALK:
450 		return (AF_APPLETALK);
451 	case LINUX_AF_NETLINK:
452 		return (AF_NETLINK);
453 	}
454 	return (-1);
455 }
456 
457 int
bsd_to_linux_domain(int domain)458 bsd_to_linux_domain(int domain)
459 {
460 
461 	switch (domain) {
462 	case AF_UNSPEC:
463 		return (LINUX_AF_UNSPEC);
464 	case AF_LOCAL:
465 		return (LINUX_AF_UNIX);
466 	case AF_INET:
467 		return (LINUX_AF_INET);
468 	case AF_INET6:
469 		return (LINUX_AF_INET6);
470 	case AF_CCITT:
471 		return (LINUX_AF_AX25);
472 	case AF_IPX:
473 		return (LINUX_AF_IPX);
474 	case AF_APPLETALK:
475 		return (LINUX_AF_APPLETALK);
476 	case AF_NETLINK:
477 		return (LINUX_AF_NETLINK);
478 	}
479 	return (-1);
480 }
481 
482 /*
483  * Based on the fact that:
484  * 1. Native and Linux storage of struct sockaddr
485  * and struct sockaddr_in6 are equal.
486  * 2. On Linux sa_family is the first member of all struct sockaddr.
487  */
488 int
bsd_to_linux_sockaddr(const struct sockaddr * sa,struct l_sockaddr ** lsa,socklen_t len)489 bsd_to_linux_sockaddr(const struct sockaddr *sa, struct l_sockaddr **lsa,
490     socklen_t len)
491 {
492 	struct l_sockaddr *kosa;
493 	int bdom;
494 
495 	*lsa = NULL;
496 	if (len < 2 || len > UCHAR_MAX)
497 		return (EINVAL);
498 	bdom = bsd_to_linux_domain(sa->sa_family);
499 	if (bdom == -1)
500 		return (EAFNOSUPPORT);
501 
502 	kosa = malloc(len, M_LINUX, M_WAITOK);
503 	bcopy(sa, kosa, len);
504 	kosa->sa_family = bdom;
505 	*lsa = kosa;
506 	return (0);
507 }
508 
509 int
linux_to_bsd_sockaddr(const struct l_sockaddr * osa,struct sockaddr ** sap,socklen_t * len)510 linux_to_bsd_sockaddr(const struct l_sockaddr *osa, struct sockaddr **sap,
511     socklen_t *len)
512 {
513 	struct sockaddr *sa;
514 	struct l_sockaddr *kosa;
515 #ifdef INET6
516 	struct sockaddr_in6 *sin6;
517 	bool  oldv6size;
518 #endif
519 	char *name;
520 	int salen, bdom, error, hdrlen, namelen;
521 
522 	if (*len < 2 || *len > UCHAR_MAX)
523 		return (EINVAL);
524 
525 	salen = *len;
526 
527 #ifdef INET6
528 	oldv6size = false;
529 	/*
530 	 * Check for old (pre-RFC2553) sockaddr_in6. We may accept it
531 	 * if it's a v4-mapped address, so reserve the proper space
532 	 * for it.
533 	 */
534 	if (salen == sizeof(struct sockaddr_in6) - sizeof(uint32_t)) {
535 		salen += sizeof(uint32_t);
536 		oldv6size = true;
537 	}
538 #endif
539 
540 	kosa = malloc(salen, M_SONAME, M_WAITOK);
541 
542 	if ((error = copyin(osa, kosa, *len)))
543 		goto out;
544 
545 	bdom = linux_to_bsd_domain(kosa->sa_family);
546 	if (bdom == -1) {
547 		error = EAFNOSUPPORT;
548 		goto out;
549 	}
550 
551 #ifdef INET6
552 	/*
553 	 * Older Linux IPv6 code uses obsolete RFC2133 struct sockaddr_in6,
554 	 * which lacks the scope id compared with RFC2553 one. If we detect
555 	 * the situation, reject the address and write a message to system log.
556 	 *
557 	 * Still accept addresses for which the scope id is not used.
558 	 */
559 	if (oldv6size) {
560 		if (bdom == AF_INET6) {
561 			sin6 = (struct sockaddr_in6 *)kosa;
562 			if (IN6_IS_ADDR_V4MAPPED(&sin6->sin6_addr) ||
563 			    (!IN6_IS_ADDR_LINKLOCAL(&sin6->sin6_addr) &&
564 			     !IN6_IS_ADDR_SITELOCAL(&sin6->sin6_addr) &&
565 			     !IN6_IS_ADDR_V4COMPAT(&sin6->sin6_addr) &&
566 			     !IN6_IS_ADDR_UNSPECIFIED(&sin6->sin6_addr) &&
567 			     !IN6_IS_ADDR_MULTICAST(&sin6->sin6_addr))) {
568 				sin6->sin6_scope_id = 0;
569 			} else {
570 				linux_msg(curthread,
571 				    "obsolete pre-RFC2553 sockaddr_in6 rejected");
572 				error = EINVAL;
573 				goto out;
574 			}
575 		} else
576 			salen -= sizeof(uint32_t);
577 	}
578 #endif
579 	if (bdom == AF_INET) {
580 		if (salen < sizeof(struct sockaddr_in)) {
581 			error = EINVAL;
582 			goto out;
583 		}
584 		salen = sizeof(struct sockaddr_in);
585 	}
586 
587 	if (bdom == AF_LOCAL && salen > sizeof(struct sockaddr_un)) {
588 		hdrlen = offsetof(struct sockaddr_un, sun_path);
589 		name = ((struct sockaddr_un *)kosa)->sun_path;
590 		if (*name == '\0') {
591 			/*
592 			 * Linux abstract namespace starts with a NULL byte.
593 			 * XXX We do not support abstract namespace yet.
594 			 */
595 			namelen = strnlen(name + 1, salen - hdrlen - 1) + 1;
596 		} else
597 			namelen = strnlen(name, salen - hdrlen);
598 		salen = hdrlen + namelen;
599 		if (salen > sizeof(struct sockaddr_un)) {
600 			error = ENAMETOOLONG;
601 			goto out;
602 		}
603 	}
604 
605 	if (bdom == AF_NETLINK) {
606 		if (salen < sizeof(struct sockaddr_nl)) {
607 			error = EINVAL;
608 			goto out;
609 		}
610 		salen = sizeof(struct sockaddr_nl);
611 	}
612 
613 	sa = (struct sockaddr *)kosa;
614 	sa->sa_family = bdom;
615 	sa->sa_len = salen;
616 
617 	*sap = sa;
618 	*len = salen;
619 	return (0);
620 
621 out:
622 	free(kosa, M_SONAME);
623 	return (error);
624 }
625 
626 void
linux_dev_shm_create(void)627 linux_dev_shm_create(void)
628 {
629 	int error;
630 
631 	error = make_dev_p(MAKEDEV_CHECKNAME | MAKEDEV_WAITOK, &dev_shm_cdev,
632 	    &dev_shm_cdevsw, NULL, UID_ROOT, GID_WHEEL, 0, "shm/.mountpoint");
633 	if (error != 0) {
634 		printf("%s: failed to create device node, error %d\n",
635 		    __func__, error);
636 	}
637 }
638 
639 void
linux_dev_shm_destroy(void)640 linux_dev_shm_destroy(void)
641 {
642 
643 	destroy_dev(dev_shm_cdev);
644 }
645 
646 int
bsd_to_linux_bits_(int value,struct bsd_to_linux_bitmap * bitmap,size_t mapcnt,int no_value)647 bsd_to_linux_bits_(int value, struct bsd_to_linux_bitmap *bitmap,
648     size_t mapcnt, int no_value)
649 {
650 	int bsd_mask, bsd_value, linux_mask, linux_value;
651 	int linux_ret;
652 	size_t i;
653 	bool applied;
654 
655 	applied = false;
656 	linux_ret = 0;
657 	for (i = 0; i < mapcnt; ++i) {
658 		bsd_mask = bitmap[i].bsd_mask;
659 		bsd_value = bitmap[i].bsd_value;
660 		if (bsd_mask == 0)
661 			bsd_mask = bsd_value;
662 
663 		linux_mask = bitmap[i].linux_mask;
664 		linux_value = bitmap[i].linux_value;
665 		if (linux_mask == 0)
666 			linux_mask = linux_value;
667 
668 		/*
669 		 * If a mask larger than just the value is set, we explicitly
670 		 * want to make sure that only this bit we mapped within that
671 		 * mask is set.
672 		 */
673 		if ((value & bsd_mask) == bsd_value) {
674 			linux_ret = (linux_ret & ~linux_mask) | linux_value;
675 			applied = true;
676 		}
677 	}
678 
679 	if (!applied)
680 		return (no_value);
681 	return (linux_ret);
682 }
683 
684 int
linux_to_bsd_bits_(int value,struct bsd_to_linux_bitmap * bitmap,size_t mapcnt,int no_value)685 linux_to_bsd_bits_(int value, struct bsd_to_linux_bitmap *bitmap,
686     size_t mapcnt, int no_value)
687 {
688 	int bsd_mask, bsd_value, linux_mask, linux_value;
689 	int bsd_ret;
690 	size_t i;
691 	bool applied;
692 
693 	applied = false;
694 	bsd_ret = 0;
695 	for (i = 0; i < mapcnt; ++i) {
696 		bsd_mask = bitmap[i].bsd_mask;
697 		bsd_value = bitmap[i].bsd_value;
698 		if (bsd_mask == 0)
699 			bsd_mask = bsd_value;
700 
701 		linux_mask = bitmap[i].linux_mask;
702 		linux_value = bitmap[i].linux_value;
703 		if (linux_mask == 0)
704 			linux_mask = linux_value;
705 
706 		/*
707 		 * If a mask larger than just the value is set, we explicitly
708 		 * want to make sure that only this bit we mapped within that
709 		 * mask is set.
710 		 */
711 		if ((value & linux_mask) == linux_value) {
712 			bsd_ret = (bsd_ret & ~bsd_mask) | bsd_value;
713 			applied = true;
714 		}
715 	}
716 
717 	if (!applied)
718 		return (no_value);
719 	return (bsd_ret);
720 }
721 
722 void
linux_to_bsd_poll_events(struct thread * td,int fd,short lev,short * bev)723 linux_to_bsd_poll_events(struct thread *td, int fd, short lev,
724     short *bev)
725 {
726 	struct proc *p = td->td_proc;
727 	struct filedesc *fdp;
728 	struct file *fp;
729 	int error;
730 	short bits = 0;
731 
732 	if (lev & LINUX_POLLIN)
733 		bits |= POLLIN;
734 	if (lev & LINUX_POLLPRI)
735 		bits |=	POLLPRI;
736 	if (lev & LINUX_POLLOUT)
737 		bits |= POLLOUT;
738 	if (lev & LINUX_POLLERR)
739 		bits |= POLLERR;
740 	if (lev & LINUX_POLLHUP)
741 		bits |= POLLHUP;
742 	if (lev & LINUX_POLLNVAL)
743 		bits |= POLLNVAL;
744 	if (lev & LINUX_POLLRDNORM)
745 		bits |= POLLRDNORM;
746 	if (lev & LINUX_POLLRDBAND)
747 		bits |= POLLRDBAND;
748 	if (lev & LINUX_POLLWRBAND)
749 		bits |= POLLWRBAND;
750 	if (lev & LINUX_POLLWRNORM)
751 		bits |= POLLWRNORM;
752 
753 	if (lev & LINUX_POLLRDHUP) {
754 		/*
755 		 * It seems that the Linux silencly ignores POLLRDHUP
756 		 * on non-socket file descriptors unlike FreeBSD, where
757 		 * events bits is more strictly checked (POLLSTANDARD).
758 		 */
759 		fdp = p->p_fd;
760 		error = fget_unlocked(fdp, fd, &cap_no_rights, &fp);
761 		if (error == 0) {
762 			/*
763 			 * XXX. On FreeBSD POLLRDHUP applies only to
764 			 * stream sockets.
765 			 */
766 			if (fp->f_type == DTYPE_SOCKET)
767 				bits |= POLLRDHUP;
768 			fdrop(fp, td);
769 		}
770 	}
771 
772 	if (lev & LINUX_POLLMSG)
773 		LINUX_RATELIMIT_MSG_OPT1("unsupported POLLMSG, events(%d)", lev);
774 	if (lev & LINUX_POLLREMOVE)
775 		LINUX_RATELIMIT_MSG_OPT1("unsupported POLLREMOVE, events(%d)", lev);
776 
777 	*bev = bits;
778 }
779 
780 void
bsd_to_linux_poll_events(short bev,short * lev)781 bsd_to_linux_poll_events(short bev, short *lev)
782 {
783 	short bits = 0;
784 
785 	if (bev & POLLIN)
786 		bits |= LINUX_POLLIN;
787 	if (bev & POLLPRI)
788 		bits |=	LINUX_POLLPRI;
789 	if (bev & (POLLOUT | POLLWRNORM))
790 		/*
791 		 * POLLWRNORM is equal to POLLOUT on FreeBSD,
792 		 * but not on Linux
793 		 */
794 		bits |= LINUX_POLLOUT;
795 	if (bev & POLLERR)
796 		bits |= LINUX_POLLERR;
797 	if (bev & POLLHUP)
798 		bits |= LINUX_POLLHUP;
799 	if (bev & POLLNVAL)
800 		bits |= LINUX_POLLNVAL;
801 	if (bev & POLLRDNORM)
802 		bits |= LINUX_POLLRDNORM;
803 	if (bev & POLLRDBAND)
804 		bits |= LINUX_POLLRDBAND;
805 	if (bev & POLLWRBAND)
806 		bits |= LINUX_POLLWRBAND;
807 	if (bev & POLLRDHUP)
808 		bits |= LINUX_POLLRDHUP;
809 
810 	*lev = bits;
811 }
812 
813 bool
linux_use_real_ifname(const struct ifnet * ifp)814 linux_use_real_ifname(const struct ifnet *ifp)
815 {
816 
817 	return (use_real_ifnames);
818 }
819