libkern/crypto/corecrypto_md5.c

   1 #include <libkern/crypto/crypto_internal.h>
   2 #include <libkern/crypto/md5.h>
   3 #include <kern/debug.h>
   4 #include <corecrypto/ccdigest.h>
   5
   6 static uint64_t
   7 getCount(MD5_CTX *ctx)
   8 {
   9         return (((uint64_t)ctx->count[0]) << 32) | (ctx->count[1]);
  10 }
  11
  12 static void
  13 setCount(MD5_CTX *ctx, uint64_t count)
  14 {
  15         ctx->count[0] = (uint32_t)(count >> 32);
  16         ctx->count[1] = (uint32_t)count;
  17 }
  18
  19 /* Copy a ccdigest ctx into a legacy MD5 context */
  20 static void
  21 DiToMD5(const struct ccdigest_info *di, struct ccdigest_ctx *di_ctx, MD5_CTX *md5_ctx)
  22 {
  23         setCount(md5_ctx, ccdigest_nbits(di, di_ctx) / 8 + ccdigest_num(di, di_ctx));
  24         memcpy(md5_ctx->buffer, ccdigest_data(di, di_ctx), di->block_size);
  25         memcpy(md5_ctx->state, ccdigest_state_ccn(di, di_ctx), di->state_size);
  26 }
  27
  28 /* Copy a legacy MD5 context into a ccdigest ctx  */
  29 static void
  30 MD5ToDi(const struct ccdigest_info *di, MD5_CTX *md5_ctx, struct ccdigest_ctx *di_ctx)
  31 {
  32         uint64_t count = getCount(md5_ctx);
  33
  34         ccdigest_num(di, di_ctx) = (unsigned)(count % di->block_size);
  35         ccdigest_nbits(di, di_ctx) = (count - ccdigest_num(di, di_ctx)) * 8;
  36         memcpy(ccdigest_data(di, di_ctx), md5_ctx->buffer, di->block_size);
  37         memcpy(ccdigest_state_ccn(di, di_ctx), md5_ctx->state, di->state_size);
  38 }
  39
  40 void
  41 MD5Init(MD5_CTX *ctx)
  42 {
  43         const struct ccdigest_info *di = g_crypto_funcs->ccmd5_di;
  44         ccdigest_di_decl(di, di_ctx);
  45
  46         g_crypto_funcs->ccdigest_init_fn(di, di_ctx);
  47
  48         DiToMD5(di, di_ctx, ctx);
  49 }
  50
  51 void
  52 MD5Update(MD5_CTX *ctx, const void *data, unsigned int len)
  53 {
  54         const struct ccdigest_info *di = g_crypto_funcs->ccmd5_di;
  55         ccdigest_di_decl(di, di_ctx);
  56
  57         MD5ToDi(di, ctx, di_ctx);
  58         g_crypto_funcs->ccdigest_update_fn(di, di_ctx, len, data);
  59         DiToMD5(di, di_ctx, ctx);
  60 }
  61
  62 void
  63 MD5Final(unsigned char digest[MD5_DIGEST_LENGTH], MD5_CTX *ctx)
  64 {
  65         const struct ccdigest_info *di = g_crypto_funcs->ccmd5_di;
  66         ccdigest_di_decl(di, di_ctx);
  67
  68         MD5ToDi(di, ctx, di_ctx);
  69         ccdigest_final(di, di_ctx, digest);
  70 }