NAME    [Toc]    [Back]

       MDC2, MDC2_Init, MDC2_Update, MDC2_Final - MDC2 hash function

LIBRARY    [Toc]    [Back]

       libcrypto, -lcrypto

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.

       MDC2() 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 may be used if the message is not
       completely stored in memory:

       MDC2_Init() initializes a MDC2_CTX structure.

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

       MDC2_Final() 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
       EVP_DigestInit(3) etc. instead of calling the hash functions
 directly.

RETURN VALUES    [Toc]    [Back]

       MDC2() returns a pointer to the hash value.

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

CONFORMING TO    [Toc]    [Back]

       ISO/IEC 10118-2, with DES

SEE ALSO    [Toc]    [Back]

       openssl_sha(3), EVP_DigestInit(3)

HISTORY    [Toc]    [Back]

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



2000-07-22                    0.9.6g                      mdc2(3)