NAME    [Toc]    [Back]

       MDC2, MDC2_Init, MDC2_Update, MDC2_Final - MDC2 hash function

SYNOPSIS    [Toc]    [Back]

       #include <openssl/mdc2.h>

       unsigned char *MDC2(
               const  unsigned  char   *d,   unsigned   long   n,
       unsigned char *md ); void MDC2_Init(
               MDC2_CTX *c ); void MDC2_Update(
               MDC2_CTX    *c,   const   unsigned   char   *data,
       unsigned long len ); void MDC2_Final(
               unsigned char *md, MDC2_CTX *c );

DESCRIPTION    [Toc]    [Back]

       MDC2 is a method to construct hash functions with 128  bit
       output  from block ciphers.  These functions are an implementation
 of MDC2 with DES.

       The MDC2() function computes the MDC2  message  digest  of
       the  n  bytes  at  d  and places it in md (which must have
       space for MDC2_DIGEST_LENGTH == 16 bytes of output). If md
       is NULL, the digest is placed in a static array.

       The  following functions can be used if the message is not
       completely stored in memory:

       The MDC2_Init() function initializes a MDC2_CTX structure.

       The  MDC2_Update()  function can be called repeatedly with
       chunks of the message to be hashed (len bytes at data).

       The MDC2_Final() function places the message digest in md,
       which  must  have space for MDC2_DIGEST_LENGTH == 16 bytes
       of output, and erases the MDC2_CTX.

       Applications should use the higher level  functions,  such
       as EVP_DigestInit(), instead of calling the hash functions
       directly.

       MDC2 conforms to ISO/IEC 10118-2, with DES.

RETURN VALUES    [Toc]    [Back]

       The MDC2() function returns a pointer to the hash value.

       The MDC2_Init(), MDC2_Update(), and MDC2_Final() functions
       do not return values.

HISTORY    [Toc]    [Back]

       The  MDC2(),  MDC2_Init(), MDC2_Update(), and MDC2_Final()
       functions are available since SSLeay 0.8.

SEE ALSO    [Toc]    [Back]

       Functions: sha(3), EVP_DigestInit(3)



                                                          MDC2(3)