granicus.if.org Git - strace/blob - desc.c

   1 /*
   2  * Copyright (c) 1991, 1992 Paul Kranenburg <pk@cs.few.eur.nl>
   3  * Copyright (c) 1993 Branko Lankester <branko@hacktic.nl>
   4  * Copyright (c) 1993, 1994, 1995, 1996 Rick Sladkey <jrs@world.std.com>
   5  * Copyright (c) 1996-1999 Wichert Akkerman <wichert@cistron.nl>
   6  * All rights reserved.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  * 3. The name of the author may not be used to endorse or promote products
  17  *    derived from this software without specific prior written permission.
  18  *
  19  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  20  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  21  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  22  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  23  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  24  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  25  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  26  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  27  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  28  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  29  */
  30
  31 #include "defs.h"
  32 #include <fcntl.h>
  33 #include <sys/file.h>
  34 #ifdef HAVE_SYS_EPOLL_H
  35 # include <sys/epoll.h>
  36 #endif
  37 #ifdef HAVE_LINUX_PERF_EVENT_H
  38 # include  <linux/perf_event.h>
  39 #endif
  40
  41 #include "xlat/fcntlcmds.h"
  42 #include "xlat/fdflags.h"
  43 #include "xlat/flockcmds.h"
  44 #include "xlat/lockfcmds.h"
  45 #include "xlat/notifyflags.h"
  46 #include "xlat/perf_event_open_flags.h"
  47
  48 /*
  49  * Assume that F_SETLK64, F_SETLKW64, and F_GETLK64 are either defined
  50  * or not defined altogether.
  51  */
  52 #if defined(F_SETLK64) && F_SETLK64 + 0 != F_SETLK
  53 # define USE_PRINTFLOCK64 1
  54 #else
  55 # define USE_PRINTFLOCK64 0
  56 #endif
  57
  58 #if USE_PRINTFLOCK64
  59
  60 # ifndef HAVE_STRUCT_FLOCK64
  61 struct flock64 {
  62         short int l_type, l_whence;
  63         int64_t l_start, l_len;
  64         int l_pid;
  65 };
  66 # endif
  67
  68 static void
  69 printflock64(struct tcb *tcp, long addr, int getlk)
  70 {
  71         struct flock64 fl;
  72
  73         if (umove(tcp, addr, &fl) < 0) {
  74                 tprints("{...}");
  75                 return;
  76         }
  77         tprints("{type=");
  78         printxval(lockfcmds, fl.l_type, "F_???");
  79         tprints(", whence=");
  80         printxval(whence_codes, fl.l_whence, "SEEK_???");
  81         tprintf(", start=%lld, len=%lld", (long long) fl.l_start, (long long) fl.l_len);
  82         if (getlk)
  83                 tprintf(", pid=%lu}", (unsigned long) fl.l_pid);
  84         else
  85                 tprints("}");
  86 }
  87 #endif /* USE_PRINTFLOCK64 */
  88
  89 static void
  90 printflock(struct tcb *tcp, long addr, int getlk)
  91 {
  92         struct flock fl;
  93         int r;
  94
  95 #if SUPPORTED_PERSONALITIES > 1
  96         if (
  97 # if SIZEOF_OFF_T > SIZEOF_LONG
  98             current_personality > 0 &&
  99 #endif
 100             current_wordsize != sizeof(fl.l_start)) {
 101                 if (current_wordsize == 4) {
 102                         /* 32-bit x86 app on x86_64 and similar cases */
 103                         struct {
 104                                 short int l_type;
 105                                 short int l_whence;
 106                                 int32_t l_start; /* off_t */
 107                                 int32_t l_len; /* off_t */
 108                                 int32_t l_pid; /* pid_t */
 109                         } fl32;
 110                         r = umove(tcp, addr, &fl32);
 111                         if (r >= 0) {
 112                                 fl.l_type = fl32.l_type;
 113                                 fl.l_whence = fl32.l_whence;
 114                                 fl.l_start = fl32.l_start;
 115                                 fl.l_len = fl32.l_len;
 116                                 fl.l_pid = fl32.l_pid;
 117                         }
 118                 } else {
 119                         /* let people know we have a problem here */
 120                         tprintf("<decode error: unsupported wordsize %d>",
 121                                 current_wordsize);
 122                         return;
 123                 }
 124         } else
 125 #endif
 126         {
 127                 r = umove(tcp, addr, &fl);
 128         }
 129         if (r < 0) {
 130                 tprints("{...}");
 131                 return;
 132         }
 133         tprints("{type=");
 134         printxval(lockfcmds, fl.l_type, "F_???");
 135         tprints(", whence=");
 136         printxval(whence_codes, fl.l_whence, "SEEK_???");
 137 #if SIZEOF_OFF_T > SIZEOF_LONG
 138         tprintf(", start=%lld, len=%lld", fl.l_start, fl.l_len);
 139 #else
 140         tprintf(", start=%ld, len=%ld", fl.l_start, fl.l_len);
 141 #endif
 142         if (getlk)
 143                 tprintf(", pid=%lu}", (unsigned long) fl.l_pid);
 144         else
 145                 tprints("}");
 146 }
 147
 148 int
 149 sys_fcntl(struct tcb *tcp)
 150 {
 151         if (entering(tcp)) {
 152                 printfd(tcp, tcp->u_arg[0]);
 153                 tprints(", ");
 154                 printxval(fcntlcmds, tcp->u_arg[1], "F_???");
 155                 switch (tcp->u_arg[1]) {
 156                 case F_SETFD:
 157                         tprints(", ");
 158                         printflags(fdflags, tcp->u_arg[2], "FD_???");
 159                         break;
 160                 case F_SETOWN: case F_DUPFD:
 161 #ifdef F_DUPFD_CLOEXEC
 162                 case F_DUPFD_CLOEXEC:
 163 #endif
 164                         tprintf(", %ld", tcp->u_arg[2]);
 165                         break;
 166                 case F_SETFL:
 167                         tprints(", ");
 168                         tprint_open_modes(tcp->u_arg[2]);
 169                         break;
 170                 case F_SETLK: case F_SETLKW:
 171                         tprints(", ");
 172                         printflock(tcp, tcp->u_arg[2], 0);
 173                         break;
 174 #if USE_PRINTFLOCK64
 175                 case F_SETLK64: case F_SETLKW64:
 176                         tprints(", ");
 177                         printflock64(tcp, tcp->u_arg[2], 0);
 178                         break;
 179 #endif /* USE_PRINTFLOCK64 */
 180 #ifdef F_NOTIFY
 181                 case F_NOTIFY:
 182                         tprints(", ");
 183                         printflags(notifyflags, tcp->u_arg[2], "DN_???");
 184                         break;
 185 #endif
 186 #ifdef F_SETLEASE
 187                 case F_SETLEASE:
 188                         tprints(", ");
 189                         printxval(lockfcmds, tcp->u_arg[2], "F_???");
 190                         break;
 191 #endif
 192                 }
 193         }
 194         else {
 195                 switch (tcp->u_arg[1]) {
 196                 case F_DUPFD:
 197 #ifdef F_DUPFD_CLOEXEC
 198                 case F_DUPFD_CLOEXEC:
 199 #endif
 200                 case F_SETFD: case F_SETFL:
 201                 case F_SETLK: case F_SETLKW:
 202                 case F_SETOWN: case F_GETOWN:
 203 #ifdef F_NOTIFY
 204                 case F_NOTIFY:
 205 #endif
 206 #ifdef F_SETLEASE
 207                 case F_SETLEASE:
 208 #endif
 209                         break;
 210                 case F_GETFD:
 211                         if (syserror(tcp) || tcp->u_rval == 0)
 212                                 return 0;
 213                         tcp->auxstr = sprintflags("flags ", fdflags, tcp->u_rval);
 214                         return RVAL_HEX|RVAL_STR;
 215                 case F_GETFL:
 216                         if (syserror(tcp))
 217                                 return 0;
 218                         tcp->auxstr = sprint_open_modes(tcp->u_rval);
 219                         return RVAL_HEX|RVAL_STR;
 220                 case F_GETLK:
 221                         tprints(", ");
 222                         printflock(tcp, tcp->u_arg[2], 1);
 223                         break;
 224 #if USE_PRINTFLOCK64
 225                 case F_GETLK64:
 226                         tprints(", ");
 227                         printflock64(tcp, tcp->u_arg[2], 1);
 228                         break;
 229 #endif
 230 #ifdef F_GETLEASE
 231                 case F_GETLEASE:
 232                         if (syserror(tcp))
 233                                 return 0;
 234                         tcp->auxstr = xlookup(lockfcmds, tcp->u_rval);
 235                         return RVAL_HEX|RVAL_STR;
 236 #endif
 237                 default:
 238                         tprintf(", %#lx", tcp->u_arg[2]);
 239                         break;
 240                 }
 241         }
 242         return 0;
 243 }
 244
 245 #ifdef LOCK_SH
 246
 247 int
 248 sys_flock(struct tcb *tcp)
 249 {
 250         if (entering(tcp)) {
 251                 printfd(tcp, tcp->u_arg[0]);
 252                 tprints(", ");
 253                 printflags(flockcmds, tcp->u_arg[1], "LOCK_???");
 254         }
 255         return 0;
 256 }
 257 #endif /* LOCK_SH */
 258
 259 int
 260 sys_close(struct tcb *tcp)
 261 {
 262         if (entering(tcp)) {
 263                 printfd(tcp, tcp->u_arg[0]);
 264         }
 265         return 0;
 266 }
 267
 268 static int
 269 do_dup2(struct tcb *tcp, int flags_arg)
 270 {
 271         if (entering(tcp)) {
 272                 printfd(tcp, tcp->u_arg[0]);
 273                 tprints(", ");
 274                 printfd(tcp, tcp->u_arg[1]);
 275                 if (flags_arg >= 0) {
 276                         tprints(", ");
 277                         printflags(open_mode_flags, tcp->u_arg[flags_arg], "O_???");
 278                 }
 279         }
 280         return 0;
 281 }
 282
 283 int
 284 sys_dup2(struct tcb *tcp)
 285 {
 286         return do_dup2(tcp, -1);
 287 }
 288
 289 int
 290 sys_dup3(struct tcb *tcp)
 291 {
 292         return do_dup2(tcp, 2);
 293 }
 294
 295 #if defined(ALPHA)
 296 int
 297 sys_getdtablesize(struct tcb *tcp)
 298 {
 299         return 0;
 300 }
 301 #endif
 302
 303 static int
 304 decode_select(struct tcb *tcp, long *args, enum bitness_t bitness)
 305 {
 306         int i, j;
 307         int nfds, fdsize;
 308         fd_set *fds;
 309         const char *sep;
 310         long arg;
 311
 312         /* Kernel truncates arg[0] to int, we do the same. */
 313         nfds = (int) args[0];
 314
 315         /* Kernel rejects negative nfds, so we don't parse it either. */
 316         if (nfds < 0) {
 317                 nfds = 0;
 318                 fds = NULL;
 319         }
 320         /* Beware of select(2^31-1, NULL, NULL, NULL) and similar... */
 321         if (nfds > 1024*1024)
 322                 nfds = 1024*1024;
 323
 324         /*
 325          * We had bugs a-la "while (j < args[0])" and "umoven(args[0])" below.
 326          * Instead of args[0], use nfds for fd count, fdsize for array lengths.
 327          */
 328         fdsize = (((nfds + 7) / 8) + current_wordsize-1) & -current_wordsize;
 329
 330         if (entering(tcp)) {
 331                 tprintf("%d", (int) args[0]);
 332
 333                 if (fdsize > 0) {
 334                         fds = malloc(fdsize);
 335                         if (!fds)
 336                                 die_out_of_memory();
 337                 }
 338                 for (i = 0; i < 3; i++) {
 339                         arg = args[i+1];
 340                         if (arg == 0) {
 341                                 tprints(", NULL");
 342                                 continue;
 343                         }
 344                         if (!verbose(tcp) || !fds) {
 345                                 tprintf(", %#lx", arg);
 346                                 continue;
 347                         }
 348                         if (umoven(tcp, arg, fdsize, (char *) fds) < 0) {
 349                                 tprints(", [?]");
 350                                 continue;
 351                         }
 352                         tprints(", [");
 353                         for (j = 0, sep = "";; j++) {
 354                                 j = next_set_bit(fds, j, nfds);
 355                                 if (j < 0)
 356                                         break;
 357                                 tprints(sep);
 358                                 printfd(tcp, j);
 359                                 sep = " ";
 360                         }
 361                         tprints("]");
 362                 }
 363                 free(fds);
 364                 tprints(", ");
 365                 printtv_bitness(tcp, args[4], bitness, 0);
 366         }
 367         else {
 368                 static char outstr[1024];
 369                 char *outptr;
 370 #define end_outstr (outstr + sizeof(outstr))
 371                 int ready_fds;
 372
 373                 if (syserror(tcp))
 374                         return 0;
 375
 376                 ready_fds = tcp->u_rval;
 377                 if (ready_fds == 0) {
 378                         tcp->auxstr = "Timeout";
 379                         return RVAL_STR;
 380                 }
 381
 382                 fds = malloc(fdsize);
 383                 if (!fds)
 384                         die_out_of_memory();
 385
 386                 outptr = outstr;
 387                 sep = "";
 388                 for (i = 0; i < 3 && ready_fds > 0; i++) {
 389                         int first = 1;
 390
 391                         arg = args[i+1];
 392                         if (!arg || umoven(tcp, arg, fdsize, (char *) fds) < 0)
 393                                 continue;
 394                         for (j = 0;; j++) {
 395                                 j = next_set_bit(fds, j, nfds);
 396                                 if (j < 0)
 397                                         break;
 398                                 /* +2 chars needed at the end: ']',NUL */
 399                                 if (outptr < end_outstr - (sizeof(", except [") + sizeof(int)*3 + 2)) {
 400                                         if (first) {
 401                                                 outptr += sprintf(outptr, "%s%s [%u",
 402                                                         sep,
 403                                                         i == 0 ? "in" : i == 1 ? "out" : "except",
 404                                                         j
 405                                                 );
 406                                                 first = 0;
 407                                                 sep = ", ";
 408                                         }
 409                                         else {
 410                                                 outptr += sprintf(outptr, " %u", j);
 411                                         }
 412                                 }
 413                                 if (--ready_fds == 0)
 414                                         break;
 415                         }
 416                         if (outptr != outstr)
 417                                 *outptr++ = ']';
 418                 }
 419                 free(fds);
 420                 /* This contains no useful information on SunOS.  */
 421                 if (args[4]) {
 422                         if (outptr < end_outstr - (10 + TIMEVAL_TEXT_BUFSIZE)) {
 423                                 outptr += sprintf(outptr, "%sleft ", sep);
 424                                 outptr = sprinttv(outptr, tcp, args[4], bitness, /*special:*/ 0);
 425                         }
 426                 }
 427                 *outptr = '\0';
 428                 tcp->auxstr = outstr;
 429                 return RVAL_STR;
 430 #undef end_outstr
 431         }
 432         return 0;
 433 }
 434
 435 int
 436 sys_oldselect(struct tcb *tcp)
 437 {
 438         long args[5];
 439
 440         if (umoven(tcp, tcp->u_arg[0], sizeof args, (char *) args) < 0) {
 441                 tprints("[...]");
 442                 return 0;
 443         }
 444         return decode_select(tcp, args, BITNESS_CURRENT);
 445 }
 446
 447 #ifdef ALPHA
 448 int
 449 sys_osf_select(struct tcb *tcp)
 450 {
 451         long *args = tcp->u_arg;
 452         return decode_select(tcp, args, BITNESS_32);
 453 }
 454 #endif
 455
 456 #include "xlat/epollctls.h"
 457 #include "xlat/epollevents.h"
 458 #include "xlat/epollflags.h"
 459
 460 /* Not aliased to printargs_ld: we want it to have a distinct address */
 461 int
 462 sys_epoll_create(struct tcb *tcp)
 463 {
 464         return printargs_ld(tcp);
 465 }
 466
 467 int
 468 sys_epoll_create1(struct tcb *tcp)
 469 {
 470         if (entering(tcp))
 471                 printflags(epollflags, tcp->u_arg[0], "EPOLL_???");
 472         return 0;
 473 }
 474
 475 #ifdef HAVE_SYS_EPOLL_H
 476 static void
 477 print_epoll_event(struct epoll_event *ev)
 478 {
 479         tprints("{");
 480         printflags(epollevents, ev->events, "EPOLL???");
 481         /* We cannot know what format the program uses, so print u32 and u64
 482            which will cover every value.  */
 483         tprintf(", {u32=%" PRIu32 ", u64=%" PRIu64 "}}",
 484                 ev->data.u32, ev->data.u64);
 485 }
 486 #endif
 487
 488 int
 489 sys_epoll_ctl(struct tcb *tcp)
 490 {
 491         if (entering(tcp)) {
 492                 printfd(tcp, tcp->u_arg[0]);
 493                 tprints(", ");
 494                 printxval(epollctls, tcp->u_arg[1], "EPOLL_CTL_???");
 495                 tprints(", ");
 496                 printfd(tcp, tcp->u_arg[2]);
 497                 tprints(", ");
 498                 if (tcp->u_arg[3] == 0)
 499                         tprints("NULL");
 500                 else {
 501 #ifdef HAVE_SYS_EPOLL_H
 502                         struct epoll_event ev;
 503                         if (
 504 #ifdef EPOLL_CTL_DEL
 505                             (tcp->u_arg[1] != EPOLL_CTL_DEL) &&
 506 #endif
 507                             umove(tcp, tcp->u_arg[3], &ev) == 0)
 508                                 print_epoll_event(&ev);
 509                         else
 510 #endif
 511                                 tprintf("%lx", tcp->u_arg[3]);
 512                 }
 513         }
 514         return 0;
 515 }
 516
 517 static void
 518 epoll_wait_common(struct tcb *tcp)
 519 {
 520         if (entering(tcp)) {
 521                 printfd(tcp, tcp->u_arg[0]);
 522                 tprints(", ");
 523         } else {
 524                 if (syserror(tcp))
 525                         tprintf("%lx", tcp->u_arg[1]);
 526                 else if (tcp->u_rval == 0)
 527                         tprints("{}");
 528                 else {
 529 #ifdef HAVE_SYS_EPOLL_H
 530                         struct epoll_event ev, *start, *cur, *end;
 531                         int failed = 0;
 532
 533                         tprints("{");
 534                         start = (struct epoll_event *) tcp->u_arg[1];
 535                         end = start + tcp->u_rval;
 536                         for (cur = start; cur < end; ++cur) {
 537                                 if (cur > start)
 538                                         tprints(", ");
 539                                 if (umove(tcp, (long) cur, &ev) == 0)
 540                                         print_epoll_event(&ev);
 541                                 else {
 542                                         tprints("?");
 543                                         failed = 1;
 544                                         break;
 545                                 }
 546                         }
 547                         tprints("}");
 548                         if (failed)
 549                                 tprintf(" %#lx", (long) start);
 550 #else
 551                         tprints("{...}");
 552 #endif
 553                 }
 554                 tprintf(", %d, %d", (int) tcp->u_arg[2], (int) tcp->u_arg[3]);
 555         }
 556 }
 557
 558 int
 559 sys_epoll_wait(struct tcb *tcp)
 560 {
 561         epoll_wait_common(tcp);
 562         return 0;
 563 }
 564
 565 int
 566 sys_epoll_pwait(struct tcb *tcp)
 567 {
 568         epoll_wait_common(tcp);
 569         if (exiting(tcp)) {
 570                 tprints(", ");
 571                 /* NB: kernel requires arg[5] == NSIG / 8 */
 572                 print_sigset_addr_len(tcp, tcp->u_arg[4], tcp->u_arg[5]);
 573                 tprintf(", %lu", tcp->u_arg[5]);
 574         }
 575         return 0;
 576 }
 577
 578 int
 579 sys_select(struct tcb *tcp)
 580 {
 581         return decode_select(tcp, tcp->u_arg, BITNESS_CURRENT);
 582 }
 583
 584 int
 585 sys_pselect6(struct tcb *tcp)
 586 {
 587         int rc = decode_select(tcp, tcp->u_arg, BITNESS_CURRENT);
 588         if (entering(tcp)) {
 589                 long r;
 590                 struct {
 591                         unsigned long ptr;
 592                         unsigned long len;
 593                 } data;
 594 #if SUPPORTED_PERSONALITIES > 1 && SIZEOF_LONG > 4
 595                 if (current_wordsize == 4) {
 596                         struct {
 597                                 uint32_t ptr;
 598                                 uint32_t len;
 599                         } data32;
 600                         r = umove(tcp, tcp->u_arg[5], &data32);
 601                         data.ptr = data32.ptr;
 602                         data.len = data32.len;
 603                 } else
 604 #endif
 605                         r = umove(tcp, tcp->u_arg[5], &data);
 606                 if (r < 0)
 607                         tprintf(", %#lx", tcp->u_arg[5]);
 608                 else {
 609                         tprints(", {");
 610                         /* NB: kernel requires data.len == NSIG / 8 */
 611                         print_sigset_addr_len(tcp, data.ptr, data.len);
 612                         tprintf(", %lu}", data.len);
 613                 }
 614         }
 615         return rc;
 616 }
 617
 618 static int
 619 do_eventfd(struct tcb *tcp, int flags_arg)
 620 {
 621         if (entering(tcp)) {
 622                 tprintf("%lu", tcp->u_arg[0]);
 623                 if (flags_arg >= 0) {
 624                         tprints(", ");
 625                         printflags(open_mode_flags, tcp->u_arg[flags_arg], "O_???");
 626                 }
 627         }
 628         return 0;
 629 }
 630
 631 int
 632 sys_eventfd(struct tcb *tcp)
 633 {
 634         return do_eventfd(tcp, -1);
 635 }
 636
 637 int
 638 sys_eventfd2(struct tcb *tcp)
 639 {
 640         return do_eventfd(tcp, 1);
 641 }
 642
 643 int
 644 sys_perf_event_open(struct tcb *tcp)
 645 {
 646         if (entering(tcp)) {
 647                 tprintf("%#lx, %d, %d, %d, ",
 648                         tcp->u_arg[0],
 649                         (int) tcp->u_arg[1],
 650                         (int) tcp->u_arg[2],
 651                         (int) tcp->u_arg[3]);
 652                 printflags(perf_event_open_flags, tcp->u_arg[4],
 653                            "PERF_FLAG_???");
 654         }
 655         return 0;
 656 }