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