osfmk/corecrypto/ccsha1/src/ccdigest_final_64be.c

   1 /*
   2  *  ccdigest_final_64be.c
   3  *  corecrypto
   4  *
   5  *  Created by Michael Brouwer on 12/1/10.
   6  *  Copyright 2010,2011 Apple Inc. All rights reserved.
   7  *
   8  */
   9
  10 #include <corecrypto/ccdigest_priv.h>
  11 #include <corecrypto/cc_priv.h>
  12
  13 /* This can be used for SHA1, SHA256 and SHA224 */
  14 void ccdigest_final_64be(const struct ccdigest_info *di, ccdigest_ctx_t ctx,
  15                          unsigned char *digest) {
  16     ccdigest_nbits(di, ctx) += ccdigest_num(di, ctx) * 8;
  17     ccdigest_data(di, ctx)[ccdigest_num(di, ctx)++] = 0x80;
  18
  19     /* If we don't have at least 8 bytes (for the length) left we need to add
  20      a second block. */
  21     if (ccdigest_num(di, ctx) > 64 - 8) {
  22         while (ccdigest_num(di, ctx) < 64) {
  23             ccdigest_data(di, ctx)[ccdigest_num(di, ctx)++] = 0;
  24         }
  25         di->compress(ccdigest_state(di, ctx), 1, ccdigest_data(di, ctx));
  26         ccdigest_num(di, ctx) = 0;
  27     }
  28
  29     /* pad upto block_size minus 8 with 0s */
  30     while (ccdigest_num(di, ctx) < 64 - 8) {
  31         ccdigest_data(di, ctx)[ccdigest_num(di, ctx)++] = 0;
  32     }
  33
  34     CC_STORE64_BE(ccdigest_nbits(di, ctx), ccdigest_data(di, ctx) + 64 - 8);
  35     di->compress(ccdigest_state(di, ctx), 1, ccdigest_data(di, ctx));
  36
  37     /* copy output */
  38     for (unsigned int i = 0; i < di->output_size / 4; i++) {
  39         CC_STORE32_BE(ccdigest_state_u32(di, ctx)[i], digest+(4*i));
  40     }
  41 }