xref: /xnu-11417.140.69/bsd/kern/sys_socket.c (revision 43a90889846e00bfb5cf1d255cdc0a701a1e05a4)
1 /*
2  * Copyright (c) 2000-2013 Apple Inc. All rights reserved.
3  *
4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5  *
6  * This file contains Original Code and/or Modifications of Original Code
7  * as defined in and that are subject to the Apple Public Source License
8  * Version 2.0 (the 'License'). You may not use this file except in
9  * compliance with the License. The rights granted to you under the License
10  * may not be used to create, or enable the creation or redistribution of,
11  * unlawful or unlicensed copies of an Apple operating system, or to
12  * circumvent, violate, or enable the circumvention or violation of, any
13  * terms of an Apple operating system software license agreement.
14  *
15  * Please obtain a copy of the License at
16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
17  *
18  * The Original Code and all software distributed under the License are
19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23  * Please see the License for the specific language governing rights and
24  * limitations under the License.
25  *
26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27  */
28 /*
29  * Copyright (c) 1982, 1986, 1990, 1993
30  *	The Regents of the University of California.  All rights reserved.
31  *
32  * Redistribution and use in source and binary forms, with or without
33  * modification, are permitted provided that the following conditions
34  * are met:
35  * 1. Redistributions of source code must retain the above copyright
36  *    notice, this list of conditions and the following disclaimer.
37  * 2. Redistributions in binary form must reproduce the above copyright
38  *    notice, this list of conditions and the following disclaimer in the
39  *    documentation and/or other materials provided with the distribution.
40  * 3. All advertising materials mentioning features or use of this software
41  *    must display the following acknowledgement:
42  *	This product includes software developed by the University of
43  *	California, Berkeley and its contributors.
44  * 4. Neither the name of the University nor the names of its contributors
45  *    may be used to endorse or promote products derived from this software
46  *    without specific prior written permission.
47  *
48  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
49  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
50  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
51  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
52  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
53  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
54  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
55  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
56  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
57  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
58  * SUCH DAMAGE.
59  *
60  *	@(#)sys_socket.c	8.1 (Berkeley) 6/10/93
61  */
62 /*
63  * NOTICE: This file was modified by SPARTA, Inc. in 2005 to introduce
64  * support for mandatory and extensible security protections.  This notice
65  * is included in support of clause 2.2 (b) of the Apple Public License,
66  * Version 2.0.
67  */
68 
69 #include <sys/param.h>
70 #include <sys/systm.h>
71 #include <sys/file_internal.h>
72 #include <sys/event.h>
73 #include <sys/protosw.h>
74 #include <sys/socket.h>
75 #include <sys/socketvar.h>
76 #include <sys/filio.h>                  /* XXX */
77 #include <sys/sockio.h>
78 #include <sys/stat.h>
79 #include <sys/uio.h>
80 #include <sys/filedesc.h>
81 #include <sys/kauth.h>
82 #include <sys/signalvar.h>
83 #include <sys/vnode.h>
84 
85 #include <net/if.h>
86 #include <net/route.h>
87 
88 #if CONFIG_MACF
89 #include <security/mac_framework.h>
90 #endif
91 
92 /*
93  * File operations on sockets.
94  */
95 static int soo_read(struct fileproc *, struct uio *, int, vfs_context_t ctx);
96 static int soo_write(struct fileproc *, struct uio *, int, vfs_context_t ctx);
97 static int soo_close(struct fileglob *, vfs_context_t ctx);
98 static int soo_drain(struct fileproc *, vfs_context_t ctx);
99 
100 const struct fileops socketops = {
101 	.fo_type     = DTYPE_SOCKET,
102 	.fo_read     = soo_read,
103 	.fo_write    = soo_write,
104 	.fo_ioctl    = soo_ioctl,
105 	.fo_select   = soo_select,
106 	.fo_close    = soo_close,
107 	.fo_drain    = soo_drain,
108 	.fo_kqfilter = soo_kqfilter,
109 };
110 
111 /* ARGSUSED */
112 static int
soo_read(struct fileproc * fp,struct uio * uio,__unused int flags,__unused vfs_context_t ctx)113 soo_read(struct fileproc *fp, struct uio *uio, __unused int flags,
114     __unused vfs_context_t ctx)
115 {
116 	struct socket *__single so;
117 	int stat;
118 
119 	int (*fsoreceive)(struct socket *so2, struct sockaddr **paddr,
120 	    struct uio *uio2, struct mbuf **mp0, struct mbuf **controlp,
121 	    int *flagsp);
122 
123 	if ((so = (struct socket *)fp_get_data(fp)) == NULL) {
124 		/* This is not a valid open file descriptor */
125 		return EBADF;
126 	}
127 
128 	fsoreceive = so->so_proto->pr_usrreqs->pru_soreceive;
129 
130 	stat = (*fsoreceive)(so, 0, uio, 0, 0, 0);
131 	return stat;
132 }
133 
134 /* ARGSUSED */
135 static int
soo_write(struct fileproc * fp,struct uio * uio,__unused int flags,vfs_context_t ctx)136 soo_write(struct fileproc *fp, struct uio *uio, __unused int flags,
137     vfs_context_t ctx)
138 {
139 	struct socket *__single so;
140 	int stat;
141 	int (*fsosend)(struct socket *so2, struct sockaddr *addr,
142 	    struct uio *uio2, struct mbuf *top, struct mbuf *control,
143 	    int flags2);
144 	proc_t procp;
145 
146 	if ((so = (struct socket *)fp_get_data(fp)) == NULL) {
147 		/* This is not a valid open file descriptor */
148 		return EBADF;
149 	}
150 
151 	fsosend = so->so_proto->pr_usrreqs->pru_sosend;
152 
153 	stat = (*fsosend)(so, 0, uio, 0, 0, 0);
154 
155 	/* Generation of SIGPIPE can be controlled per socket */
156 	procp = vfs_context_proc(ctx);
157 	if (stat == EPIPE && !(so->so_flags & SOF_NOSIGPIPE)) {
158 		psignal(procp, SIGPIPE);
159 	}
160 
161 	return stat;
162 }
163 
164 __private_extern__ int
soioctl(struct socket * so,u_long cmd,caddr_t __sized_by (IOCPARM_LEN (cmd))data,struct proc * p)165 soioctl(struct socket *so, u_long cmd, caddr_t __sized_by(IOCPARM_LEN(cmd)) data, struct proc *p)
166 {
167 	int error = 0;
168 	int int_arg;
169 
170 #if CONFIG_MACF_SOCKET_SUBSET
171 	error = mac_socket_check_ioctl(kauth_cred_get(), so, cmd);
172 	if (error) {
173 		return error;
174 	}
175 #endif
176 
177 	socket_lock(so, 1);
178 
179 	/* call the socket filter's ioctl handler anything but ours */
180 	if (IOCGROUP(cmd) != 'i' && IOCGROUP(cmd) != 'r') {
181 		switch (cmd) {
182 		case SIOCGASSOCIDS32:
183 		case SIOCGASSOCIDS64:
184 		case SIOCGCONNIDS32:
185 		case SIOCGCONNIDS64:
186 		case SIOCGCONNINFO32:
187 		case SIOCGCONNINFO64:
188 		case SIOCSCONNORDER:
189 		case SIOCGCONNORDER:
190 			/* don't pass to filter */
191 			break;
192 
193 		default:
194 			error = sflt_ioctl(so, cmd, data);
195 			if (error != 0) {
196 				goto out;
197 			}
198 			break;
199 		}
200 	}
201 
202 	switch (cmd) {
203 	case FIONBIO:                   /* int */
204 		bcopy(data, &int_arg, sizeof(int_arg));
205 		if (int_arg) {
206 			so->so_state |= SS_NBIO;
207 		} else {
208 			so->so_state &= ~SS_NBIO;
209 		}
210 
211 		goto out;
212 
213 	case FIOASYNC:                  /* int */
214 		bcopy(data, &int_arg, sizeof(int_arg));
215 		if (int_arg) {
216 			so->so_state |= SS_ASYNC;
217 			so->so_rcv.sb_flags |= SB_ASYNC;
218 			so->so_snd.sb_flags |= SB_ASYNC;
219 		} else {
220 			so->so_state &= ~SS_ASYNC;
221 			so->so_rcv.sb_flags &= ~SB_ASYNC;
222 			so->so_snd.sb_flags &= ~SB_ASYNC;
223 		}
224 		goto out;
225 
226 	case FIONREAD:                  /* int */
227 		bcopy(&so->so_rcv.sb_cc, data, sizeof(u_int32_t));
228 		goto out;
229 
230 	case SIOCSPGRP:                 /* int */
231 		bcopy(data, &so->so_pgid, sizeof(pid_t));
232 		goto out;
233 
234 	case SIOCGPGRP:                 /* int */
235 		bcopy(&so->so_pgid, data, sizeof(pid_t));
236 		goto out;
237 
238 	case SIOCATMARK:                /* int */
239 		int_arg = (so->so_state & SS_RCVATMARK) != 0;
240 		bcopy(&int_arg, data, sizeof(int_arg));
241 		goto out;
242 
243 	case SIOCGASSOCIDS32:           /* so_aidreq32 */
244 	case SIOCGASSOCIDS64:           /* so_aidreq64 */
245 	case SIOCGCONNIDS32:            /* so_cidreq32 */
246 	case SIOCGCONNIDS64:            /* so_cidreq64 */
247 	case SIOCGCONNINFO32:           /* so_cinforeq32 */
248 	case SIOCGCONNINFO64:           /* so_cinforeq64 */
249 	case SIOCSCONNORDER:            /* so_cordreq */
250 	case SIOCGCONNORDER:            /* so_cordreq */
251 		error = (*so->so_proto->pr_usrreqs->pru_control)(so,
252 		    cmd, data, NULL, p);
253 		goto out;
254 	}
255 
256 	/*
257 	 * Interface/routing/protocol specific ioctls:
258 	 * interface and routing ioctls should have a
259 	 * different entry since a socket's unnecessary
260 	 */
261 	if (IOCGROUP(cmd) == 'i') {
262 		error = ifioctllocked(so, cmd, data, p);
263 	} else {
264 		if (IOCGROUP(cmd) == 'r') {
265 			error = rtioctl(cmd, data, p);
266 		} else {
267 			error = (*so->so_proto->pr_usrreqs->pru_control)(so,
268 			    cmd, data, NULL, p);
269 		}
270 	}
271 
272 out:
273 	socket_unlock(so, 1);
274 
275 	if (error == EJUSTRETURN) {
276 		error = 0;
277 	}
278 
279 	return error;
280 }
281 
282 int
soo_ioctl(struct fileproc * fp,u_long cmd,caddr_t __sized_by (IOCPARM_LEN (cmd))data,vfs_context_t ctx)283 soo_ioctl(struct fileproc *fp, u_long cmd, caddr_t __sized_by(IOCPARM_LEN(cmd)) data, vfs_context_t ctx)
284 {
285 	struct socket *__single so;
286 	proc_t procp = vfs_context_proc(ctx);
287 
288 	if ((so = (struct socket *)fp_get_data(fp)) == NULL) {
289 		/* This is not a valid open file descriptor */
290 		return EBADF;
291 	}
292 
293 	return soioctl(so, cmd, data, procp);
294 }
295 
296 int
soo_select(struct fileproc * fp,int which,void * wql,vfs_context_t ctx)297 soo_select(struct fileproc *fp, int which, void *wql, vfs_context_t ctx)
298 {
299 	struct socket *__single so = (struct socket *)fp_get_data(fp);
300 	int retnum = 0;
301 	proc_t procp;
302 
303 	if (so == NULL || so == (struct socket *)-1) {
304 		return 0;
305 	}
306 
307 	procp = vfs_context_proc(ctx);
308 
309 	socket_lock(so, 1);
310 	switch (which) {
311 	case FREAD:
312 		so->so_rcv.sb_flags |= SB_SEL;
313 		if (soreadable(so)) {
314 			retnum = 1;
315 			so->so_rcv.sb_flags &= ~SB_SEL;
316 			goto done;
317 		}
318 		selrecord(procp, &so->so_rcv.sb_sel, wql);
319 		break;
320 
321 	case FWRITE:
322 		so->so_snd.sb_flags |= SB_SEL;
323 		if (sowriteable(so)) {
324 			retnum = 1;
325 			so->so_snd.sb_flags &= ~SB_SEL;
326 			goto done;
327 		}
328 		selrecord(procp, &so->so_snd.sb_sel, wql);
329 		break;
330 
331 	case 0:
332 		so->so_rcv.sb_flags |= SB_SEL;
333 		if (so->so_oobmark || (so->so_state & SS_RCVATMARK)) {
334 			retnum = 1;
335 			so->so_rcv.sb_flags &= ~SB_SEL;
336 			goto done;
337 		}
338 		selrecord(procp, &so->so_rcv.sb_sel, wql);
339 		break;
340 	}
341 
342 done:
343 	socket_unlock(so, 1);
344 	return retnum;
345 }
346 
347 int
soo_stat(struct socket * so,void * ub,int isstat64)348 soo_stat(struct socket *so, void *ub, int isstat64)
349 {
350 	int ret;
351 	/* warning avoidance ; protected by isstat64 */
352 	struct stat *sb = (struct stat *)0;
353 	/* warning avoidance ; protected by isstat64 */
354 	struct stat64 *sb64 = (struct stat64 *)0;
355 
356 #if CONFIG_MACF_SOCKET_SUBSET
357 	ret = mac_socket_check_stat(kauth_cred_get(), so);
358 	if (ret) {
359 		return ret;
360 	}
361 #endif
362 
363 	if (isstat64 != 0) {
364 		sb64 = (struct stat64 *)ub;
365 		bzero((caddr_t)sb64, sizeof(*sb64));
366 	} else {
367 		sb = (struct stat *)ub;
368 		bzero((caddr_t)sb, sizeof(*sb));
369 	}
370 
371 	socket_lock(so, 1);
372 	if (isstat64 != 0) {
373 		sb64->st_mode = S_IFSOCK;
374 		if ((so->so_state & SS_CANTRCVMORE) == 0 ||
375 		    so->so_rcv.sb_cc != 0) {
376 			sb64->st_mode |= S_IRUSR | S_IRGRP | S_IROTH;
377 		}
378 		if ((so->so_state & SS_CANTSENDMORE) == 0) {
379 			sb64->st_mode |= S_IWUSR | S_IWGRP | S_IWOTH;
380 		}
381 		sb64->st_size = so->so_rcv.sb_cc - so->so_rcv.sb_ctl;
382 		sb64->st_uid = kauth_cred_getuid(so->so_cred);
383 		sb64->st_gid = kauth_cred_getgid(so->so_cred);
384 	} else {
385 		sb->st_mode = S_IFSOCK;
386 		if ((so->so_state & SS_CANTRCVMORE) == 0 ||
387 		    so->so_rcv.sb_cc != 0) {
388 			sb->st_mode |= S_IRUSR | S_IRGRP | S_IROTH;
389 		}
390 		if ((so->so_state & SS_CANTSENDMORE) == 0) {
391 			sb->st_mode |= S_IWUSR | S_IWGRP | S_IWOTH;
392 		}
393 		sb->st_size = so->so_rcv.sb_cc - so->so_rcv.sb_ctl;
394 		sb->st_uid = kauth_cred_getuid(so->so_cred);
395 		sb->st_gid = kauth_cred_getgid(so->so_cred);
396 	}
397 
398 	ret = (*so->so_proto->pr_usrreqs->pru_sense)(so, ub, isstat64);
399 	socket_unlock(so, 1);
400 	return ret;
401 }
402 
403 /* ARGSUSED */
404 static int
soo_close(struct fileglob * fg,__unused vfs_context_t ctx)405 soo_close(struct fileglob *fg, __unused vfs_context_t ctx)
406 {
407 	int error = 0;
408 	struct socket *__single sp;
409 
410 	sp = (struct socket *)fg_get_data(fg);
411 	fg_set_data(fg, NULL);
412 
413 	if (sp) {
414 		error = soclose(sp);
415 	}
416 
417 	return error;
418 }
419 
420 static int
soo_drain(struct fileproc * fp,__unused vfs_context_t ctx)421 soo_drain(struct fileproc *fp, __unused vfs_context_t ctx)
422 {
423 	int error = 0;
424 	struct socket *__single so = (struct socket *)fp_get_data(fp);
425 
426 	if (so) {
427 		socket_lock(so, 1);
428 		so->so_state |= SS_DRAINING;
429 
430 		wakeup((caddr_t)&so->so_timeo);
431 		sorwakeup(so);
432 		sowwakeup(so);
433 		soevent(so, SO_FILT_HINT_LOCKED);
434 
435 		socket_unlock(so, 1);
436 	}
437 
438 	return error;
439 }
440 
441 /*
442  * 's' group ioctls.
443  *
444  * The switch statement below does nothing at runtime, as it serves as a
445  * compile time check to ensure that all of the socket 's' ioctls (those
446  * in the 's' group going thru soo_ioctl) that are made available by the
447  * networking stack is unique.  This works as long as this routine gets
448  * updated each time a new interface ioctl gets added.
449  *
450  * Any failures at compile time indicates duplicated ioctl values.
451  */
452 static __attribute__((unused)) void
soioctl_cassert(void)453 soioctl_cassert(void)
454 {
455 	/*
456 	 * This is equivalent to _CASSERT() and the compiler wouldn't
457 	 * generate any instructions, thus for compile time only.
458 	 */
459 	switch ((u_long)0) {
460 	case 0:
461 
462 	/* bsd/sys/sockio.h */
463 	case SIOCSHIWAT:
464 	case SIOCGHIWAT:
465 	case SIOCSLOWAT:
466 	case SIOCGLOWAT:
467 	case SIOCATMARK:
468 	case SIOCSPGRP:
469 	case SIOCGPGRP:
470 	case SIOCGASSOCIDS32:
471 	case SIOCGASSOCIDS64:
472 	case SIOCGCONNIDS32:
473 	case SIOCGCONNIDS64:
474 	case SIOCGCONNINFO32:
475 	case SIOCGCONNINFO64:
476 	case SIOCSCONNORDER:
477 	case SIOCGCONNORDER:
478 		;
479 	}
480 }
481