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_drain    = soo_drain,
 108         .fo_kqfilter = soo_kqfilter,
 109 };
 110
 111 /* ARGSUSED */
 112 static int
 113 soo_read(struct fileproc *fp, struct uio *uio, __unused int flags,
 114     __unused vfs_context_t ctx)
 115 {
 116         struct socket *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->fp_glob->fg_data) == 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
 136 soo_write(struct fileproc *fp, struct uio *uio, __unused int flags,
 137     vfs_context_t ctx)
 138 {
 139         struct socket *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->fp_glob->fg_data) == 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
 165 soioctl(struct socket *so, u_long cmd, caddr_t 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 SIOCSETOT:                 /* int; deprecated */
 244                 error = EOPNOTSUPP;
 245                 goto out;
 246
 247         case SIOCGASSOCIDS32:           /* so_aidreq32 */
 248         case SIOCGASSOCIDS64:           /* so_aidreq64 */
 249         case SIOCGCONNIDS32:            /* so_cidreq32 */
 250         case SIOCGCONNIDS64:            /* so_cidreq64 */
 251         case SIOCGCONNINFO32:           /* so_cinforeq32 */
 252         case SIOCGCONNINFO64:           /* so_cinforeq64 */
 253         case SIOCSCONNORDER:            /* so_cordreq */
 254         case SIOCGCONNORDER:            /* so_cordreq */
 255                 error = (*so->so_proto->pr_usrreqs->pru_control)(so,
 256                     cmd, data, NULL, p);
 257                 goto out;
 258         }
 259
 260         /*
 261          * Interface/routing/protocol specific ioctls:
 262          * interface and routing ioctls should have a
 263          * different entry since a socket's unnecessary
 264          */
 265         if (IOCGROUP(cmd) == 'i') {
 266                 error = ifioctllocked(so, cmd, data, p);
 267         } else {
 268                 if (IOCGROUP(cmd) == 'r') {
 269                         error = rtioctl(cmd, data, p);
 270                 } else {
 271                         error = (*so->so_proto->pr_usrreqs->pru_control)(so,
 272                             cmd, data, NULL, p);
 273                 }
 274         }
 275
 276 out:
 277         socket_unlock(so, 1);
 278
 279         if (error == EJUSTRETURN) {
 280                 error = 0;
 281         }
 282
 283         return error;
 284 }
 285
 286 int
 287 soo_ioctl(struct fileproc *fp, u_long cmd, caddr_t data, vfs_context_t ctx)
 288 {
 289         struct socket *so;
 290         proc_t procp = vfs_context_proc(ctx);
 291
 292         if ((so = (struct socket *)fp->fp_glob->fg_data) == NULL) {
 293                 /* This is not a valid open file descriptor */
 294                 return EBADF;
 295         }
 296
 297         return soioctl(so, cmd, data, procp);
 298 }
 299
 300 int
 301 soo_select(struct fileproc *fp, int which, void *wql, vfs_context_t ctx)
 302 {
 303         struct socket *so = (struct socket *)fp->fp_glob->fg_data;
 304         int retnum = 0;
 305         proc_t procp;
 306
 307         if (so == NULL || so == (struct socket *)-1) {
 308                 return 0;
 309         }
 310
 311         procp = vfs_context_proc(ctx);
 312
 313         socket_lock(so, 1);
 314         switch (which) {
 315         case FREAD:
 316                 so->so_rcv.sb_flags |= SB_SEL;
 317                 if (soreadable(so)) {
 318                         retnum = 1;
 319                         so->so_rcv.sb_flags &= ~SB_SEL;
 320                         goto done;
 321                 }
 322                 selrecord(procp, &so->so_rcv.sb_sel, wql);
 323                 break;
 324
 325         case FWRITE:
 326                 so->so_snd.sb_flags |= SB_SEL;
 327                 if (sowriteable(so)) {
 328                         retnum = 1;
 329                         so->so_snd.sb_flags &= ~SB_SEL;
 330                         goto done;
 331                 }
 332                 selrecord(procp, &so->so_snd.sb_sel, wql);
 333                 break;
 334
 335         case 0:
 336                 so->so_rcv.sb_flags |= SB_SEL;
 337                 if (so->so_oobmark || (so->so_state & SS_RCVATMARK)) {
 338                         retnum = 1;
 339                         so->so_rcv.sb_flags &= ~SB_SEL;
 340                         goto done;
 341                 }
 342                 selrecord(procp, &so->so_rcv.sb_sel, wql);
 343                 break;
 344         }
 345
 346 done:
 347         socket_unlock(so, 1);
 348         return retnum;
 349 }
 350
 351 int
 352 soo_stat(struct socket *so, void *ub, int isstat64)
 353 {
 354         int ret;
 355         /* warning avoidance ; protected by isstat64 */
 356         struct stat *sb = (struct stat *)0;
 357         /* warning avoidance ; protected by isstat64 */
 358         struct stat64 *sb64 = (struct stat64 *)0;
 359
 360 #if CONFIG_MACF_SOCKET_SUBSET
 361         ret = mac_socket_check_stat(kauth_cred_get(), so);
 362         if (ret) {
 363                 return ret;
 364         }
 365 #endif
 366
 367         if (isstat64 != 0) {
 368                 sb64 = (struct stat64 *)ub;
 369                 bzero((caddr_t)sb64, sizeof(*sb64));
 370         } else {
 371                 sb = (struct stat *)ub;
 372                 bzero((caddr_t)sb, sizeof(*sb));
 373         }
 374
 375         socket_lock(so, 1);
 376         if (isstat64 != 0) {
 377                 sb64->st_mode = S_IFSOCK;
 378                 if ((so->so_state & SS_CANTRCVMORE) == 0 ||
 379                     so->so_rcv.sb_cc != 0) {
 380                         sb64->st_mode |= S_IRUSR | S_IRGRP | S_IROTH;
 381                 }
 382                 if ((so->so_state & SS_CANTSENDMORE) == 0) {
 383                         sb64->st_mode |= S_IWUSR | S_IWGRP | S_IWOTH;
 384                 }
 385                 sb64->st_size = so->so_rcv.sb_cc - so->so_rcv.sb_ctl;
 386                 sb64->st_uid = kauth_cred_getuid(so->so_cred);
 387                 sb64->st_gid = kauth_cred_getgid(so->so_cred);
 388         } else {
 389                 sb->st_mode = S_IFSOCK;
 390                 if ((so->so_state & SS_CANTRCVMORE) == 0 ||
 391                     so->so_rcv.sb_cc != 0) {
 392                         sb->st_mode |= S_IRUSR | S_IRGRP | S_IROTH;
 393                 }
 394                 if ((so->so_state & SS_CANTSENDMORE) == 0) {
 395                         sb->st_mode |= S_IWUSR | S_IWGRP | S_IWOTH;
 396                 }
 397                 sb->st_size = so->so_rcv.sb_cc - so->so_rcv.sb_ctl;
 398                 sb->st_uid = kauth_cred_getuid(so->so_cred);
 399                 sb->st_gid = kauth_cred_getgid(so->so_cred);
 400         }
 401
 402         ret = (*so->so_proto->pr_usrreqs->pru_sense)(so, ub, isstat64);
 403         socket_unlock(so, 1);
 404         return ret;
 405 }
 406
 407 /* ARGSUSED */
 408 static int
 409 soo_close(struct fileglob *fg, __unused vfs_context_t ctx)
 410 {
 411         int error = 0;
 412         struct socket *sp;
 413
 414         sp = (struct socket *)fg->fg_data;
 415         fg->fg_data = NULL;
 416
 417         if (sp) {
 418                 error = soclose(sp);
 419         }
 420
 421         return error;
 422 }
 423
 424 static int
 425 soo_drain(struct fileproc *fp, __unused vfs_context_t ctx)
 426 {
 427         int error = 0;
 428         struct socket *so = (struct socket *)fp->fp_glob->fg_data;
 429
 430         if (so) {
 431                 socket_lock(so, 1);
 432                 so->so_state |= SS_DRAINING;
 433
 434                 wakeup((caddr_t)&so->so_timeo);
 435                 sorwakeup(so);
 436                 sowwakeup(so);
 437                 soevent(so, SO_FILT_HINT_LOCKED);
 438
 439                 socket_unlock(so, 1);
 440         }
 441
 442         return error;
 443 }
 444
 445 /*
 446  * 's' group ioctls.
 447  *
 448  * The switch statement below does nothing at runtime, as it serves as a
 449  * compile time check to ensure that all of the socket 's' ioctls (those
 450  * in the 's' group going thru soo_ioctl) that are made available by the
 451  * networking stack is unique.  This works as long as this routine gets
 452  * updated each time a new interface ioctl gets added.
 453  *
 454  * Any failures at compile time indicates duplicated ioctl values.
 455  */
 456 static __attribute__((unused)) void
 457 soioctl_cassert(void)
 458 {
 459         /*
 460          * This is equivalent to _CASSERT() and the compiler wouldn't
 461          * generate any instructions, thus for compile time only.
 462          */
 463         switch ((u_long)0) {
 464         case 0:
 465
 466         /* bsd/sys/sockio.h */
 467         case SIOCSHIWAT:
 468         case SIOCGHIWAT:
 469         case SIOCSLOWAT:
 470         case SIOCGLOWAT:
 471         case SIOCATMARK:
 472         case SIOCSPGRP:
 473         case SIOCGPGRP:
 474         case SIOCSETOT:
 475         case SIOCGASSOCIDS32:
 476         case SIOCGASSOCIDS64:
 477         case SIOCGCONNIDS32:
 478         case SIOCGCONNIDS64:
 479         case SIOCGCONNINFO32:
 480         case SIOCGCONNINFO64:
 481         case SIOCSCONNORDER:
 482         case SIOCGCONNORDER:
 483                 ;
 484         }
 485 }