bsd/kern/sys_socket.c

   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_kqfilter = soo_kqfilter,
 108         .fo_drain = soo_drain,
 109 };
 110
 111 /* ARGSUSED */
 112 static int
 113 soo_read(struct fileproc *fp, struct uio *uio, __unused int flags,
 114 #if !CONFIG_MACF_SOCKET
 115     __unused
 116 #endif
 117     vfs_context_t ctx)
 118 {
 119         struct socket *so;
 120         int stat;
 121 #if CONFIG_MACF_SOCKET
 122         int error;
 123 #endif
 124
 125         int (*fsoreceive)(struct socket *so2, struct sockaddr **paddr,
 126             struct uio *uio2, struct mbuf **mp0, struct mbuf **controlp,
 127             int *flagsp);
 128
 129         if ((so = (struct socket *)fp->f_fglob->fg_data) == NULL) {
 130                 /* This is not a valid open file descriptor */
 131                 return EBADF;
 132         }
 133
 134 #if CONFIG_MACF_SOCKET
 135         error = mac_socket_check_receive(vfs_context_ucred(ctx), so);
 136         if (error) {
 137                 return error;
 138         }
 139 #endif /* CONFIG_MACF_SOCKET */
 140
 141         fsoreceive = so->so_proto->pr_usrreqs->pru_soreceive;
 142
 143         stat = (*fsoreceive)(so, 0, uio, 0, 0, 0);
 144         return stat;
 145 }
 146
 147 /* ARGSUSED */
 148 static int
 149 soo_write(struct fileproc *fp, struct uio *uio, __unused int flags,
 150     vfs_context_t ctx)
 151 {
 152         struct socket *so;
 153         int stat;
 154         int (*fsosend)(struct socket *so2, struct sockaddr *addr,
 155             struct uio *uio2, struct mbuf *top, struct mbuf *control,
 156             int flags2);
 157         proc_t procp;
 158
 159 #if CONFIG_MACF_SOCKET
 160         int error;
 161 #endif
 162
 163         if ((so = (struct socket *)fp->f_fglob->fg_data) == NULL) {
 164                 /* This is not a valid open file descriptor */
 165                 return EBADF;
 166         }
 167
 168 #if CONFIG_MACF_SOCKET
 169         /* JMM - have to fetch the socket's remote addr */
 170         error = mac_socket_check_send(vfs_context_ucred(ctx), so, NULL);
 171         if (error) {
 172                 return error;
 173         }
 174 #endif /* CONFIG_MACF_SOCKET */
 175
 176         fsosend = so->so_proto->pr_usrreqs->pru_sosend;
 177
 178         stat = (*fsosend)(so, 0, uio, 0, 0, 0);
 179
 180         /* Generation of SIGPIPE can be controlled per socket */
 181         procp = vfs_context_proc(ctx);
 182         if (stat == EPIPE && !(so->so_flags & SOF_NOSIGPIPE)) {
 183                 psignal(procp, SIGPIPE);
 184         }
 185
 186         return stat;
 187 }
 188
 189 __private_extern__ int
 190 soioctl(struct socket *so, u_long cmd, caddr_t data, struct proc *p)
 191 {
 192         int error = 0;
 193         int int_arg;
 194
 195 #if CONFIG_MACF_SOCKET_SUBSET
 196         error = mac_socket_check_ioctl(kauth_cred_get(), so, cmd);
 197         if (error) {
 198                 return error;
 199         }
 200 #endif
 201
 202         socket_lock(so, 1);
 203
 204         /* call the socket filter's ioctl handler anything but ours */
 205         if (IOCGROUP(cmd) != 'i' && IOCGROUP(cmd) != 'r') {
 206                 switch (cmd) {
 207                 case SIOCGASSOCIDS32:
 208                 case SIOCGASSOCIDS64:
 209                 case SIOCGCONNIDS32:
 210                 case SIOCGCONNIDS64:
 211                 case SIOCGCONNINFO32:
 212                 case SIOCGCONNINFO64:
 213                 case SIOCSCONNORDER:
 214                 case SIOCGCONNORDER:
 215                         /* don't pass to filter */
 216                         break;
 217
 218                 default:
 219                         error = sflt_ioctl(so, cmd, data);
 220                         if (error != 0) {
 221                                 goto out;
 222                         }
 223                         break;
 224                 }
 225         }
 226
 227         switch (cmd) {
 228         case FIONBIO:                   /* int */
 229                 bcopy(data, &int_arg, sizeof(int_arg));
 230                 if (int_arg) {
 231                         so->so_state |= SS_NBIO;
 232                 } else {
 233                         so->so_state &= ~SS_NBIO;
 234                 }
 235
 236                 goto out;
 237
 238         case FIOASYNC:                  /* int */
 239                 bcopy(data, &int_arg, sizeof(int_arg));
 240                 if (int_arg) {
 241                         so->so_state |= SS_ASYNC;
 242                         so->so_rcv.sb_flags |= SB_ASYNC;
 243                         so->so_snd.sb_flags |= SB_ASYNC;
 244                 } else {
 245                         so->so_state &= ~SS_ASYNC;
 246                         so->so_rcv.sb_flags &= ~SB_ASYNC;
 247                         so->so_snd.sb_flags &= ~SB_ASYNC;
 248                 }
 249                 goto out;
 250
 251         case FIONREAD:                  /* int */
 252                 bcopy(&so->so_rcv.sb_cc, data, sizeof(u_int32_t));
 253                 goto out;
 254
 255         case SIOCSPGRP:                 /* int */
 256                 bcopy(data, &so->so_pgid, sizeof(pid_t));
 257                 goto out;
 258
 259         case SIOCGPGRP:                 /* int */
 260                 bcopy(&so->so_pgid, data, sizeof(pid_t));
 261                 goto out;
 262
 263         case SIOCATMARK:                /* int */
 264                 int_arg = (so->so_state & SS_RCVATMARK) != 0;
 265                 bcopy(&int_arg, data, sizeof(int_arg));
 266                 goto out;
 267
 268         case SIOCSETOT:                 /* int; deprecated */
 269                 error = EOPNOTSUPP;
 270                 goto out;
 271
 272         case SIOCGASSOCIDS32:           /* so_aidreq32 */
 273         case SIOCGASSOCIDS64:           /* so_aidreq64 */
 274         case SIOCGCONNIDS32:            /* so_cidreq32 */
 275         case SIOCGCONNIDS64:            /* so_cidreq64 */
 276         case SIOCGCONNINFO32:           /* so_cinforeq32 */
 277         case SIOCGCONNINFO64:           /* so_cinforeq64 */
 278         case SIOCSCONNORDER:            /* so_cordreq */
 279         case SIOCGCONNORDER:            /* so_cordreq */
 280                 error = (*so->so_proto->pr_usrreqs->pru_control)(so,
 281                     cmd, data, NULL, p);
 282                 goto out;
 283         }
 284
 285         /*
 286          * Interface/routing/protocol specific ioctls:
 287          * interface and routing ioctls should have a
 288          * different entry since a socket's unnecessary
 289          */
 290         if (IOCGROUP(cmd) == 'i') {
 291                 error = ifioctllocked(so, cmd, data, p);
 292         } else {
 293                 if (IOCGROUP(cmd) == 'r') {
 294                         error = rtioctl(cmd, data, p);
 295                 } else {
 296                         error = (*so->so_proto->pr_usrreqs->pru_control)(so,
 297                             cmd, data, NULL, p);
 298                 }
 299         }
 300
 301 out:
 302         socket_unlock(so, 1);
 303
 304         if (error == EJUSTRETURN) {
 305                 error = 0;
 306         }
 307
 308         return error;
 309 }
 310
 311 int
 312 soo_ioctl(struct fileproc *fp, u_long cmd, caddr_t data, vfs_context_t ctx)
 313 {
 314         struct socket *so;
 315         proc_t procp = vfs_context_proc(ctx);
 316
 317         if ((so = (struct socket *)fp->f_fglob->fg_data) == NULL) {
 318                 /* This is not a valid open file descriptor */
 319                 return EBADF;
 320         }
 321
 322         return soioctl(so, cmd, data, procp);
 323 }
 324
 325 int
 326 soo_select(struct fileproc *fp, int which, void *wql, vfs_context_t ctx)
 327 {
 328         struct socket *so = (struct socket *)fp->f_fglob->fg_data;
 329         int retnum = 0;
 330         proc_t procp;
 331
 332         if (so == NULL || so == (struct socket *)-1) {
 333                 return 0;
 334         }
 335
 336         procp = vfs_context_proc(ctx);
 337
 338 #if CONFIG_MACF_SOCKET
 339         if (mac_socket_check_select(vfs_context_ucred(ctx), so, which) != 0) {
 340                 return 0;
 341         }
 342 #endif /* CONFIG_MACF_SOCKET */
 343
 344
 345         socket_lock(so, 1);
 346         switch (which) {
 347         case FREAD:
 348                 so->so_rcv.sb_flags |= SB_SEL;
 349                 if (soreadable(so)) {
 350                         retnum = 1;
 351                         so->so_rcv.sb_flags &= ~SB_SEL;
 352                         goto done;
 353                 }
 354                 selrecord(procp, &so->so_rcv.sb_sel, wql);
 355                 break;
 356
 357         case FWRITE:
 358                 so->so_snd.sb_flags |= SB_SEL;
 359                 if (sowriteable(so)) {
 360                         retnum = 1;
 361                         so->so_snd.sb_flags &= ~SB_SEL;
 362                         goto done;
 363                 }
 364                 selrecord(procp, &so->so_snd.sb_sel, wql);
 365                 break;
 366
 367         case 0:
 368                 so->so_rcv.sb_flags |= SB_SEL;
 369                 if (so->so_oobmark || (so->so_state & SS_RCVATMARK)) {
 370                         retnum = 1;
 371                         so->so_rcv.sb_flags &= ~SB_SEL;
 372                         goto done;
 373                 }
 374                 selrecord(procp, &so->so_rcv.sb_sel, wql);
 375                 break;
 376         }
 377
 378 done:
 379         socket_unlock(so, 1);
 380         return retnum;
 381 }
 382
 383 int
 384 soo_stat(struct socket *so, void *ub, int isstat64)
 385 {
 386         int ret;
 387         /* warning avoidance ; protected by isstat64 */
 388         struct stat *sb = (struct stat *)0;
 389         /* warning avoidance ; protected by isstat64 */
 390         struct stat64 *sb64 = (struct stat64 *)0;
 391
 392 #if CONFIG_MACF_SOCKET_SUBSET
 393         ret = mac_socket_check_stat(kauth_cred_get(), so);
 394         if (ret) {
 395                 return ret;
 396         }
 397 #endif
 398
 399         if (isstat64 != 0) {
 400                 sb64 = (struct stat64 *)ub;
 401                 bzero((caddr_t)sb64, sizeof(*sb64));
 402         } else {
 403                 sb = (struct stat *)ub;
 404                 bzero((caddr_t)sb, sizeof(*sb));
 405         }
 406
 407         socket_lock(so, 1);
 408         if (isstat64 != 0) {
 409                 sb64->st_mode = S_IFSOCK;
 410                 if ((so->so_state & SS_CANTRCVMORE) == 0 ||
 411                     so->so_rcv.sb_cc != 0) {
 412                         sb64->st_mode |= S_IRUSR | S_IRGRP | S_IROTH;
 413                 }
 414                 if ((so->so_state & SS_CANTSENDMORE) == 0) {
 415                         sb64->st_mode |= S_IWUSR | S_IWGRP | S_IWOTH;
 416                 }
 417                 sb64->st_size = so->so_rcv.sb_cc - so->so_rcv.sb_ctl;
 418                 sb64->st_uid = kauth_cred_getuid(so->so_cred);
 419                 sb64->st_gid = kauth_cred_getgid(so->so_cred);
 420         } else {
 421                 sb->st_mode = S_IFSOCK;
 422                 if ((so->so_state & SS_CANTRCVMORE) == 0 ||
 423                     so->so_rcv.sb_cc != 0) {
 424                         sb->st_mode |= S_IRUSR | S_IRGRP | S_IROTH;
 425                 }
 426                 if ((so->so_state & SS_CANTSENDMORE) == 0) {
 427                         sb->st_mode |= S_IWUSR | S_IWGRP | S_IWOTH;
 428                 }
 429                 sb->st_size = so->so_rcv.sb_cc - so->so_rcv.sb_ctl;
 430                 sb->st_uid = kauth_cred_getuid(so->so_cred);
 431                 sb->st_gid = kauth_cred_getgid(so->so_cred);
 432         }
 433
 434         ret = (*so->so_proto->pr_usrreqs->pru_sense)(so, ub, isstat64);
 435         socket_unlock(so, 1);
 436         return ret;
 437 }
 438
 439 /* ARGSUSED */
 440 static int
 441 soo_close(struct fileglob *fg, __unused vfs_context_t ctx)
 442 {
 443         int error = 0;
 444         struct socket *sp;
 445
 446         sp = (struct socket *)fg->fg_data;
 447         fg->fg_data = NULL;
 448
 449         if (sp) {
 450                 error = soclose(sp);
 451         }
 452
 453         return error;
 454 }
 455
 456 static int
 457 soo_drain(struct fileproc *fp, __unused vfs_context_t ctx)
 458 {
 459         int error = 0;
 460         struct socket *so = (struct socket *)fp->f_fglob->fg_data;
 461
 462         if (so) {
 463                 socket_lock(so, 1);
 464                 so->so_state |= SS_DRAINING;
 465
 466                 wakeup((caddr_t)&so->so_timeo);
 467                 sorwakeup(so);
 468                 sowwakeup(so);
 469                 soevent(so, SO_FILT_HINT_LOCKED);
 470
 471                 socket_unlock(so, 1);
 472         }
 473
 474         return error;
 475 }
 476
 477 /*
 478  * 's' group ioctls.
 479  *
 480  * The switch statement below does nothing at runtime, as it serves as a
 481  * compile time check to ensure that all of the socket 's' ioctls (those
 482  * in the 's' group going thru soo_ioctl) that are made available by the
 483  * networking stack is unique.  This works as long as this routine gets
 484  * updated each time a new interface ioctl gets added.
 485  *
 486  * Any failures at compile time indicates duplicated ioctl values.
 487  */
 488 static __attribute__((unused)) void
 489 soioctl_cassert(void)
 490 {
 491         /*
 492          * This is equivalent to _CASSERT() and the compiler wouldn't
 493          * generate any instructions, thus for compile time only.
 494          */
 495         switch ((u_long)0) {
 496         case 0:
 497
 498         /* bsd/sys/sockio.h */
 499         case SIOCSHIWAT:
 500         case SIOCGHIWAT:
 501         case SIOCSLOWAT:
 502         case SIOCGLOWAT:
 503         case SIOCATMARK:
 504         case SIOCSPGRP:
 505         case SIOCGPGRP:
 506         case SIOCSETOT:
 507         case SIOCGASSOCIDS32:
 508         case SIOCGASSOCIDS64:
 509         case SIOCGCONNIDS32:
 510         case SIOCGCONNIDS64:
 511         case SIOCGCONNINFO32:
 512         case SIOCGCONNINFO64:
 513         case SIOCSCONNORDER:
 514         case SIOCGCONNORDER:
 515                 ;
 516         }
 517 }