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