bsd/kern/sys_socket.c

   1 /*
   2  * Copyright (c) 2000-2008 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 /* TODO: these should be in header file */
 101 extern int soo_ioctl(struct fileproc *, u_long, caddr_t, vfs_context_t ctx);
 102 extern int soo_stat(struct socket *, void *, int);
 103 extern int soo_select(struct fileproc *, int, void *, vfs_context_t ctx);
 104 extern int soo_kqfilter(struct fileproc *, struct knote *, vfs_context_t ctx);
 105
 106 struct fileops socketops = {
 107         soo_read, soo_write, soo_ioctl, soo_select, soo_close,
 108         soo_kqfilter, 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 //###LD will have to change
 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 #endif /* CONFIG_MACF_SOCKET */
 174
 175         fsosend = so->so_proto->pr_usrreqs->pru_sosend;
 176
 177         stat = (*fsosend)(so, 0, uio, 0, 0, 0);
 178
 179         /* Generation of SIGPIPE can be controlled per socket */
 180         procp = vfs_context_proc(ctx);
 181         if (stat == EPIPE && !(so->so_flags & SOF_NOSIGPIPE))
 182                 psignal(procp, SIGPIPE);
 183
 184         return (stat);
 185 }
 186
 187 __private_extern__ int
 188 soioctl(struct socket *so, u_long cmd, caddr_t data, struct proc *p)
 189 {
 190         int error = 0;
 191         int dropsockref = -1;
 192
 193         socket_lock(so, 1);
 194
 195         /* Call the socket filter's ioctl handler for most ioctls */
 196         if (IOCGROUP(cmd) != 'i' && IOCGROUP(cmd) != 'r') {
 197                 int filtered = 0;
 198                 struct socket_filter_entry *filter;
 199
 200                 for (filter = so->so_filt; filter && error == 0;
 201                     filter = filter->sfe_next_onsocket) {
 202                         if (filter->sfe_filter->sf_filter.sf_ioctl) {
 203                                 if (filtered == 0) {
 204                                         sflt_use(so);
 205                                         socket_unlock(so, 0);
 206                                         filtered = 1;
 207                                 }
 208                                 error = filter->sfe_filter->sf_filter.
 209                                     sf_ioctl(filter->sfe_cookie, so, cmd, data);
 210                         }
 211                 }
 212
 213                 if (filtered) {
 214                         socket_lock(so, 0);
 215                         sflt_unuse(so);
 216                 }
 217
 218                 if (error != 0)
 219                         goto out;
 220         }
 221
 222         switch (cmd) {
 223
 224         case FIONBIO:
 225                 if (*(int *)data)
 226                         so->so_state |= SS_NBIO;
 227                 else
 228                         so->so_state &= ~SS_NBIO;
 229
 230                 goto out;
 231
 232         case FIOASYNC:
 233                 if (*(int *)data) {
 234                         so->so_state |= SS_ASYNC;
 235                         so->so_rcv.sb_flags |= SB_ASYNC;
 236                         so->so_snd.sb_flags |= SB_ASYNC;
 237                 } else {
 238                         so->so_state &= ~SS_ASYNC;
 239                         so->so_rcv.sb_flags &= ~SB_ASYNC;
 240                         so->so_snd.sb_flags &= ~SB_ASYNC;
 241                 }
 242                 goto out;
 243
 244         case FIONREAD:
 245                 *(int *)data = so->so_rcv.sb_cc;
 246                 goto out;
 247
 248         case SIOCSPGRP:
 249                 so->so_pgid = *(int *)data;
 250                 goto out;
 251
 252         case SIOCGPGRP:
 253                 *(int *)data = so->so_pgid;
 254                 goto out;
 255
 256         case SIOCATMARK:
 257                 *(int *)data = (so->so_state&SS_RCVATMARK) != 0;
 258                 goto out;
 259
 260         case SIOCSETOT: {
 261                 /*
 262                  * Set socket level options here and then call protocol
 263                  * specific routine.
 264                  */
 265                 struct socket *cloned_so = NULL;
 266                 int cloned_fd = *(int *)data;
 267
 268                 /* let's make sure it's either -1 or a valid file descriptor */
 269                 if (cloned_fd != -1) {
 270                         error = file_socket(cloned_fd, &cloned_so);
 271                         if (error) {
 272                                 goto out;
 273                         }
 274                         dropsockref = cloned_fd;
 275                 }
 276
 277                 /* Always set socket non-blocking for OT */
 278                 so->so_state |= SS_NBIO;
 279                 so->so_options |= SO_DONTTRUNC | SO_WANTMORE;
 280                 so->so_flags |= SOF_NOSIGPIPE | SOF_NPX_SETOPTSHUT;
 281
 282                 if (cloned_so && so != cloned_so) {
 283                         /* Flags options */
 284                         so->so_options |=
 285                             cloned_so->so_options & ~SO_ACCEPTCONN;
 286
 287                         /* SO_LINGER */
 288                         if (so->so_options & SO_LINGER)
 289                                 so->so_linger = cloned_so->so_linger;
 290
 291                         /* SO_SNDBUF, SO_RCVBUF */
 292                         if (cloned_so->so_snd.sb_hiwat > 0) {
 293                                 if (sbreserve(&so->so_snd,
 294                                     cloned_so->so_snd.sb_hiwat) == 0) {
 295                                         error = ENOBUFS;
 296                                         goto out;
 297                                 }
 298                         }
 299                         if (cloned_so->so_rcv.sb_hiwat > 0) {
 300                                 if (sbreserve(&so->so_rcv,
 301                                     cloned_so->so_rcv.sb_hiwat) == 0) {
 302                                         error = ENOBUFS;
 303                                         goto out;
 304                                 }
 305                         }
 306
 307                         /* SO_SNDLOWAT, SO_RCVLOWAT */
 308                         so->so_snd.sb_lowat =
 309                             (cloned_so->so_snd.sb_lowat > so->so_snd.sb_hiwat) ?
 310                             so->so_snd.sb_hiwat : cloned_so->so_snd.sb_lowat;
 311                         so->so_rcv.sb_lowat =
 312                             (cloned_so->so_rcv.sb_lowat > so->so_rcv.sb_hiwat) ?
 313                             so->so_rcv.sb_hiwat : cloned_so->so_rcv.sb_lowat;
 314
 315                         /* SO_SNDTIMEO, SO_RCVTIMEO */
 316                         so->so_snd.sb_timeo = cloned_so->so_snd.sb_timeo;
 317                         so->so_rcv.sb_timeo = cloned_so->so_rcv.sb_timeo;
 318                 }
 319
 320                 error = (*so->so_proto->pr_usrreqs->pru_control)(so, cmd,
 321                     data, 0, p);
 322                 /* Just ignore protocols that do not understand it */
 323                 if (error == EOPNOTSUPP)
 324                         error = 0;
 325
 326                 goto out;
 327         }
 328         }
 329         /*
 330          * Interface/routing/protocol specific ioctls:
 331          * interface and routing ioctls should have a
 332          * different entry since a socket's unnecessary
 333          */
 334         if (IOCGROUP(cmd) == 'i') {
 335                 error = ifioctllocked(so, cmd, data, p);
 336         } else {
 337                 if (IOCGROUP(cmd) == 'r')
 338                         error = rtioctl(cmd, data, p);
 339                 else
 340                         error = (*so->so_proto->pr_usrreqs->pru_control)(so,
 341                             cmd, data, 0, p);
 342         }
 343
 344 out:
 345         if (dropsockref != -1)
 346                 file_drop(dropsockref);
 347         socket_unlock(so, 1);
 348
 349         if (error == EJUSTRETURN)
 350                 error = 0;
 351
 352         return (error);
 353 }
 354
 355 int
 356 soo_ioctl(struct fileproc *fp, u_long cmd, caddr_t data, vfs_context_t ctx)
 357 {
 358         struct socket *so;
 359         int error;
 360         proc_t procp = vfs_context_proc(ctx);
 361
 362         if ((so = (struct socket *)fp->f_fglob->fg_data) == NULL) {
 363                 /* This is not a valid open file descriptor */
 364                 return (EBADF);
 365         }
 366
 367         error = soioctl(so, cmd, data, procp);
 368
 369         if (error == 0 && cmd == SIOCSETOT)
 370                 fp->f_fglob->fg_flag |= FNONBLOCK;
 371
 372         return (error);
 373 }
 374
 375 int
 376 soo_select(struct fileproc *fp, int which, void *wql, vfs_context_t ctx)
 377 {
 378         struct socket *so = (struct socket *)fp->f_fglob->fg_data;
 379         int retnum = 0;
 380         proc_t procp;
 381
 382         if (so == NULL || so == (struct socket *)-1)
 383                 return (0);
 384
 385         procp = vfs_context_proc(ctx);
 386
 387 #if CONFIG_MACF_SOCKET
 388         if (mac_socket_check_select(vfs_context_ucred(ctx), so, which) != 0);
 389                 return (0);
 390 #endif /* CONFIG_MACF_SOCKET */
 391
 392
 393         socket_lock(so, 1);
 394         switch (which) {
 395
 396         case FREAD:
 397                 so->so_rcv.sb_flags |= SB_SEL;
 398                 if (soreadable(so)) {
 399                         retnum = 1;
 400                         so->so_rcv.sb_flags &= ~SB_SEL;
 401                         goto done;
 402                 }
 403                 selrecord(procp, &so->so_rcv.sb_sel, wql);
 404                 break;
 405
 406         case FWRITE:
 407                 so->so_snd.sb_flags |= SB_SEL;
 408                 if (sowriteable(so)) {
 409                         retnum = 1;
 410                         so->so_snd.sb_flags &= ~SB_SEL;
 411                         goto done;
 412                 }
 413                 selrecord(procp, &so->so_snd.sb_sel, wql);
 414                 break;
 415
 416         case 0:
 417                 so->so_rcv.sb_flags |= SB_SEL;
 418                 if (so->so_oobmark || (so->so_state & SS_RCVATMARK)) {
 419                         retnum = 1;
 420                         so->so_rcv.sb_flags &= ~SB_SEL;
 421                         goto done;
 422                 }
 423                 selrecord(procp, &so->so_rcv.sb_sel, wql);
 424                 break;
 425         }
 426
 427 done:
 428         socket_unlock(so, 1);
 429         return (retnum);
 430 }
 431
 432 int
 433 soo_stat(struct socket *so, void *ub, int isstat64)
 434 {
 435         int ret;
 436         /* warning avoidance ; protected by isstat64 */
 437         struct stat *sb = (struct stat *)0;
 438         /* warning avoidance ; protected by isstat64 */
 439         struct stat64 *sb64 = (struct stat64 *)0;
 440
 441 #if CONFIG_MACF_SOCKET
 442         ret = mac_socket_check_stat(kauth_cred_get(), so);
 443         if (ret)
 444                 return (ret);
 445 #endif
 446
 447         if (isstat64 != 0) {
 448                 sb64 = (struct stat64 *)ub;
 449                 bzero((caddr_t)sb64, sizeof (*sb64));
 450         } else {
 451                 sb = (struct stat *)ub;
 452                 bzero((caddr_t)sb, sizeof (*sb));
 453         }
 454
 455         socket_lock(so, 1);
 456         if (isstat64 != 0) {
 457                 sb64->st_mode = S_IFSOCK;
 458                 if ((so->so_state & SS_CANTRCVMORE) == 0 ||
 459                     so->so_rcv.sb_cc != 0)
 460                         sb64->st_mode |= S_IRUSR | S_IRGRP | S_IROTH;
 461                 if ((so->so_state & SS_CANTSENDMORE) == 0)
 462                         sb64->st_mode |= S_IWUSR | S_IWGRP | S_IWOTH;
 463                 sb64->st_size = so->so_rcv.sb_cc - so->so_rcv.sb_ctl;
 464                 sb64->st_uid = so->so_uid;
 465                 sb64->st_gid = -1;      /* XXX -- what else to do? */
 466         } else {
 467                 sb->st_mode = S_IFSOCK;
 468                 if ((so->so_state & SS_CANTRCVMORE) == 0 ||
 469                     so->so_rcv.sb_cc != 0)
 470                         sb->st_mode |= S_IRUSR | S_IRGRP | S_IROTH;
 471                 if ((so->so_state & SS_CANTSENDMORE) == 0)
 472                         sb->st_mode |= S_IWUSR | S_IWGRP | S_IWOTH;
 473                 sb->st_size = so->so_rcv.sb_cc - so->so_rcv.sb_ctl;
 474                 sb->st_uid = so->so_uid;
 475                 sb->st_gid = -1;        /* XXX -- what else to do? */
 476         }
 477
 478         ret = (*so->so_proto->pr_usrreqs->pru_sense)(so, ub, isstat64);
 479         socket_unlock(so, 1);
 480         return (ret);
 481 }
 482
 483 /* ARGSUSED */
 484 static int
 485 soo_close(struct fileglob *fg, __unused vfs_context_t ctx)
 486 {
 487         int error = 0;
 488         struct socket *sp;
 489
 490         sp = (struct socket *)fg->fg_data;
 491         fg->fg_data = NULL;
 492
 493         if (sp)
 494                 error = soclose(sp);
 495
 496         return (error);
 497 }
 498
 499 static int
 500 soo_drain(struct fileproc *fp, __unused vfs_context_t ctx)
 501 {
 502         int error = 0;
 503         struct socket *so = (struct socket *)fp->f_fglob->fg_data;
 504
 505         if (so) {
 506                 socket_lock(so, 1);
 507                 so->so_state |= SS_DRAINING;
 508
 509                 wakeup((caddr_t)&so->so_timeo);
 510                 sorwakeup(so);
 511                 sowwakeup(so);
 512
 513                 socket_unlock(so, 1);
 514         }
 515
 516         return (error);
 517 }