text: /*-
   */
  #ifndef _CRYPTO_SCRYPT_H_
  #define _CRYPTO_SCRYPT_H_
  
  
  #include <stdint.h>
  
  #ifdef __cplusplus
  extern "C" {
  #endif
  
  /**
   * crypto_scrypt(passwd, passwdlen, salt, saltlen, N, r, p, buf, buflen):
   * Compute scrypt(passwd[0 .. passwdlen - 1], salt[0 .. saltlen - 1], N, r,
   * p, buflen) and write the result into buf.  The parameters r, p, and buflen
   * must satisfy r * p < 2^30 and buflen <= (2^32 - 1) * 32.  The parameter N
   * must be a power of 2 greater than 1.
   *
   * libscrypt_scrypt(passwd, passwdlen, salt, saltlen, N, r, p, buf, buflen):
   * password; duh
   * N: CPU AND RAM cost (first modifier)
   * r: RAM Cost
   * p: CPU cost (parallelisation)
   * In short, N is your main performance modifier. Values of r = 8, p = 1 are
   * standard unless you want to modify the CPU/RAM ratio.
   * Return 0 on success; or -1 on error.
   */
  int libscrypt_scrypt(const uint8_t *, size_t, const uint8_t *, size_t, uint64_t,
                       uint32_t, uint32_t, /*@out@*/ uint8_t *, size_t);
  
  /* Converts a series of input parameters to a MCF form for storage */
  int libscrypt_mcf(uint32_t N, uint32_t r, uint32_t p, const char *salt,
                    const char *hash, char *mcf);
  
  /* Checks a given MCF against a password */
  int libscrypt_check(char *mcf, const char *password);
  
  #ifdef __cplusplus
  }
  #endif
  
  /* Sane default values */
  #define SCRYPT_HASH_LEN 64 /* This can be user defined - 
   *but 64 is the reference size
   */
  #define SCRYPT_SAFE_N 30 /* This is much higher than you want. It's just
  			  * a blocker for insane defines
  			  */
  #define SCRYPT_SALT_LEN 16 /* This is just a recommended size */
  #define SCRYPT_MCF_LEN 125 /* mcf is 120 byte + nul */
  #define SCRYPT_MCF_ID "$s1"
  #define SCRYPT_N 16384
  #define SCRYPT_r 8
  #define SCRYPT_p 16
  #endif /* !_CRYPTO_SCRYPT_H_ */
  