ld/ldbuildid.c

   1 /* ldbuildid.c - Build Id support routines
   2    Copyright 2013, 2014 Free Software Foundation, Inc.
   3
   4    This file is part of the GNU Binutils.
   5
   6    This program is free software; you can redistribute it and/or modify
   7    it under the terms of the GNU General Public License as published by
   8    the Free Software Foundation; either version 3 of the License, or
   9    (at your option) any later version.
  10
  11    This program is distributed in the hope that it will be useful,
  12    but WITHOUT ANY WARRANTY; without even the implied warranty of
  13    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14    GNU General Public License for more details.
  15
  16    You should have received a copy of the GNU General Public License
  17    along with this program; if not, write to the Free Software
  18    Foundation, Inc., 51 Franklin Street - Fifth Floor, Boston,
  19    MA 02110-1301, USA.  */
  20
  21 #include "sysdep.h"
  22 #include "bfd.h"
  23 #include "safe-ctype.h"
  24 #include "md5.h"
  25 #include "sha1.h"
  26 #include "ldbuildid.h"
  27
  28 #define streq(a,b)     strcmp ((a), (b)) == 0
  29 #define strneq(a,b,n)  strncmp ((a), (b), (n)) == 0
  30
  31 bfd_boolean
  32 validate_build_id_style (const char *style)
  33 {
  34  if ((streq (style, "md5")) || (streq (style, "sha1"))
  35 #ifndef __MINGW32__
  36      || (streq (style, "uuid"))
  37 #endif
  38      || (strneq (style, "0x", 2)))
  39    return TRUE;
  40
  41  return FALSE;
  42 }
  43
  44 bfd_size_type
  45 compute_build_id_size (const char *style)
  46 {
  47   if (streq (style, "md5") || streq (style, "uuid"))
  48     return  128 / 8;
  49
  50   if (streq (style, "sha1"))
  51     return  160 / 8;
  52
  53   if (strneq (style, "0x", 2))
  54     {
  55       bfd_size_type size = 0;
  56       /* ID is in string form (hex).  Count the bytes.  */
  57       const char *id = style + 2;
  58
  59       do
  60         {
  61           if (ISXDIGIT (id[0]) && ISXDIGIT (id[1]))
  62             {
  63               ++size;
  64               id += 2;
  65             }
  66           else if (*id == '-' || *id == ':')
  67             ++id;
  68           else
  69             {
  70               size = 0;
  71               break;
  72             }
  73         } while (*id != '\0');
  74       return size;
  75     }
  76
  77   return 0;
  78 }
  79
  80 static unsigned char
  81 read_hex (const char xdigit)
  82 {
  83   if (ISDIGIT (xdigit))
  84     return xdigit - '0';
  85
  86   if (ISUPPER (xdigit))
  87     return xdigit - 'A' + 0xa;
  88
  89   if (ISLOWER (xdigit))
  90     return xdigit - 'a' + 0xa;
  91
  92   abort ();
  93   return 0;
  94 }
  95
  96 bfd_boolean
  97 generate_build_id (bfd *abfd,
  98                    const char *style,
  99                    checksum_fn checksum_contents,
 100                    unsigned char *id_bits,
 101                    int size)
 102 {
 103   if (streq (style, "md5"))
 104     {
 105       struct md5_ctx ctx;
 106
 107       md5_init_ctx (&ctx);
 108       if (!(*checksum_contents) (abfd, (sum_fn) &md5_process_bytes, &ctx))
 109         return FALSE;
 110       md5_finish_ctx (&ctx, id_bits);
 111     }
 112   else if (streq (style, "sha1"))
 113     {
 114       struct sha1_ctx ctx;
 115
 116       sha1_init_ctx (&ctx);
 117       if (!(*checksum_contents) (abfd, (sum_fn) &sha1_process_bytes, &ctx))
 118         return FALSE;
 119       sha1_finish_ctx (&ctx, id_bits);
 120     }
 121 #ifndef __MINGW32__
 122   else if (streq (style, "uuid"))
 123     {
 124       int n;
 125       int fd = open ("/dev/urandom", O_RDONLY);
 126
 127       if (fd < 0)
 128         return FALSE;
 129       n = read (fd, id_bits, size);
 130       close (fd);
 131       if (n < size)
 132         return FALSE;
 133     }
 134 #endif
 135   else if (strneq (style, "0x", 2))
 136     {
 137       /* ID is in string form (hex).  Convert to bits.  */
 138       const char *id = style + 2;
 139       size_t n = 0;
 140
 141       do
 142         {
 143           if (ISXDIGIT (id[0]) && ISXDIGIT (id[1]))
 144             {
 145               id_bits[n] = read_hex (*id++) << 4;
 146               id_bits[n++] |= read_hex (*id++);
 147             }
 148           else if (*id == '-' || *id == ':')
 149             ++id;
 150           else
 151             abort ();           /* Should have been validated earlier.  */
 152         } while (*id != '\0');
 153     }
 154   else
 155     abort ();                   /* Should have been validated earlier.  */
 156
 157   return TRUE;
 158 }