src/hash/hash_collisiondetect.h

   1 /*
   2  * Copyright (C) the libgit2 contributors. All rights reserved.
   3  *
   4  * This file is part of libgit2, distributed under the GNU GPL v2 with
   5  * a Linking Exception. For full terms see the included COPYING file.
   6  */
   7
   8 #ifndef INCLUDE_hash_collisiondetect_h__
   9 #define INCLUDE_hash_collisiondetect_h__
  10
  11 #include "hash.h"
  12 #include "sha1dc/sha1.h"
  13
  14 struct git_hash_ctx {
  15         SHA1_CTX c;
  16 };
  17
  18 #define git_hash_global_init() 0
  19 #define git_hash_ctx_init(ctx) git_hash_init(ctx)
  20 #define git_hash_ctx_cleanup(ctx)
  21
  22 GIT_INLINE(int) git_hash_init(git_hash_ctx *ctx)
  23 {
  24         assert(ctx);
  25         SHA1DCInit(&ctx->c);
  26         return 0;
  27 }
  28
  29 GIT_INLINE(int) git_hash_update(git_hash_ctx *ctx, const void *data, size_t len)
  30 {
  31         assert(ctx);
  32         SHA1DCUpdate(&ctx->c, data, len);
  33         return 0;
  34 }
  35
  36 GIT_INLINE(int) git_hash_final(git_oid *out, git_hash_ctx *ctx)
  37 {
  38         assert(ctx);
  39         if (SHA1DCFinal(out->id, &ctx->c)) {
  40                 giterr_set(GITERR_SHA1, "SHA1 collision attack detected");
  41                 return -1;
  42         }
  43
  44         return 0;
  45 }
  46
  47 #endif /* INCLUDE_hash_collisiondetect_h__ */