1  /*
       2   * This is an implementation of the National Institute of Standards
       3   * and Technology US Secure Hash Algorithm 1 (SHA1).
       4   *
       5   * Public api for steve reid's public domain SHA-1 implementation.
       6   * This file is in the public domain.
       7   */
       8  
       9  #ifndef _CRYPT_ALG_SHA1_H
      10  #define _CRYPT_ALG_SHA1_H 1
      11  
      12  /* Structure to save state of computation between the single steps.  */
      13  struct sha1_ctx
      14  {
      15    uint32_t state[5];
      16    uint32_t count[2];
      17    uint8_t  buffer[64];
      18  };
      19  
      20  /* Initialize structure containing state of computation.
      21     (RFC 3174, 6.1)  */
      22  extern void sha1_init_ctx (struct sha1_ctx *ctx);
      23  
      24  /* Starting with the result of former calls of this function (or the
      25     initialization function) update the context for the next LEN bytes
      26     starting at BUFFER.  LEN does not need to be a multiple of 64.  */
      27  extern void sha1_process_bytes (const void *buffer, struct sha1_ctx *ctx, size_t size);
      28  
      29  /* Process the remaining bytes in the buffer and write the finalized
      30     hash to RESBUF, which should point to 20 bytes of storage.  All
      31     data written to CTX is erased before returning from the function.  */
      32  extern void *sha1_finish_ctx (struct sha1_ctx *ctx, void *resbuf);
      33  
      34  #endif