sysdeps/unix/sysv/linux/getsockopt.c

   1 /* Copyright (C) 2015-2024 Free Software Foundation, Inc.
   2    This file is part of the GNU C Library.
   3
   4    The GNU C Library is free software; you can redistribute it and/or
   5    modify it under the terms of the GNU Lesser General Public
   6    License as published by the Free Software Foundation; either
   7    version 2.1 of the License, or (at your option) any later version.
   8
   9    The GNU C Library is distributed in the hope that it will be useful,
  10    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  12    Lesser General Public License for more details.
  13
  14    You should have received a copy of the GNU Lesser General Public
  15    License along with the GNU C Library; if not, see
  16    <https://www.gnu.org/licenses/>.  */
  17
  18 #include <sys/socket.h>
  19 #include <time.h>
  20 #include <sysdep.h>
  21 #include <socketcall.h>
  22 #include <socket-constants-time64.h>
  23
  24 static int
  25 getsockopt_syscall (int fd, int level, int optname, void *optval,
  26                     socklen_t *len)
  27 {
  28 #ifdef __ASSUME_GETSOCKOPT_SYSCALL
  29   return INLINE_SYSCALL (getsockopt, 5, fd, level, optname, optval, len);
  30 #else
  31   return SOCKETCALL (getsockopt, fd, level, optname, optval, len);
  32 #endif
  33 }
  34
  35 #ifndef __ASSUME_TIME64_SYSCALLS
  36 static int
  37 getsockopt32 (int fd, int level, int optname, void *optval,
  38               socklen_t *len)
  39 {
  40   int r = -1;
  41
  42   if (level != SOL_SOCKET)
  43     return r;
  44
  45   switch (optname)
  46     {
  47     case COMPAT_SO_RCVTIMEO_NEW:
  48     case COMPAT_SO_SNDTIMEO_NEW:
  49       {
  50         if (optname == COMPAT_SO_RCVTIMEO_NEW)
  51           optname = COMPAT_SO_RCVTIMEO_OLD;
  52         if (optname == COMPAT_SO_SNDTIMEO_NEW)
  53           optname = COMPAT_SO_SNDTIMEO_OLD;
  54
  55         struct __timeval32 tv32;
  56         r = getsockopt_syscall (fd, level, optname, &tv32,
  57                                 (socklen_t[]) { sizeof tv32 });
  58         if (r < 0)
  59           break;
  60
  61         /* POSIX states that if the size of the option value is greater than
  62            then option length, the option value argument shall be silently
  63            truncated.  */
  64         if (*len >= sizeof (struct __timeval64))
  65           {
  66             struct __timeval64 *tv64 = (struct __timeval64 *) optval;
  67             *tv64 = valid_timeval32_to_timeval64 (tv32);
  68             *len = sizeof (*tv64);
  69           }
  70         else
  71           memcpy (optval, &tv32, sizeof tv32);
  72       }
  73       break;
  74
  75     case COMPAT_SO_TIMESTAMP_NEW:
  76     case COMPAT_SO_TIMESTAMPNS_NEW:
  77       {
  78         if (optname == COMPAT_SO_TIMESTAMP_NEW)
  79           optname = COMPAT_SO_TIMESTAMP_OLD;
  80         if (optname == COMPAT_SO_TIMESTAMPNS_NEW)
  81           optname = COMPAT_SO_TIMESTAMPNS_OLD;
  82         r = getsockopt_syscall (fd, level, optname, optval, len);
  83       }
  84       break;
  85     }
  86
  87   return r;
  88 }
  89 #endif
  90
  91 int
  92 __getsockopt (int fd, int level, int optname, void *optval, socklen_t *len)
  93 {
  94   int r = getsockopt_syscall (fd, level, optname, optval, len);
  95
  96 #ifndef __ASSUME_TIME64_SYSCALLS
  97   if (r == -1 && errno == ENOPROTOOPT)
  98     r = getsockopt32 (fd, level, optname, optval, len);
  99 #endif
 100
 101  return r;
 102 }
 103 weak_alias (__getsockopt, getsockopt)
 104 #if __TIMESIZE != 64
 105 weak_alias (__getsockopt, __getsockopt64)
 106 #endif