sha1dc_git.c

   1 #include "git-compat-util.h"
   2 #include "sha1dc_git.h"
   3 #include "hex.h"
   4
   5 #ifdef DC_SHA1_EXTERNAL
   6 /*
   7  * Same as SHA1DCInit, but with default save_hash=0
   8  */
   9 void git_SHA1DCInit(SHA1_CTX *ctx)
  10 {
  11         SHA1DCInit(ctx);
  12         SHA1DCSetSafeHash(ctx, 0);
  13 }
  14 #endif
  15
  16 /*
  17  * Same as SHA1DCFinal, but convert collision attack case into a verbose die().
  18  */
  19 void git_SHA1DCFinal(unsigned char hash[20], SHA1_CTX *ctx)
  20 {
  21         if (!SHA1DCFinal(hash, ctx))
  22                 return;
  23         die("SHA-1 appears to be part of a collision attack: %s",
  24             hash_to_hex_algop(hash, &hash_algos[GIT_HASH_SHA1]));
  25 }
  26
  27 /*
  28  * Same as SHA1DCUpdate, but adjust types to match git's usual interface.
  29  */
  30 void git_SHA1DCUpdate(SHA1_CTX *ctx, const void *vdata, unsigned long len)
  31 {
  32         const char *data = vdata;
  33         /* We expect an unsigned long, but sha1dc only takes an int */
  34         while (len > INT_MAX) {
  35                 SHA1DCUpdate(ctx, data, INT_MAX);
  36                 data += INT_MAX;
  37                 len -= INT_MAX;
  38         }
  39         SHA1DCUpdate(ctx, data, len);
  40 }