| =pod |
| |
| =head1 NAME |
| |
| MDC2, MDC2_Init, MDC2_Update, MDC2_Final - MDC2 hash function |
| |
| =head1 SYNOPSIS |
| |
| #include <openssl/mdc2.h> |
| |
| unsigned char *MDC2(const unsigned char *d, unsigned long n, |
| unsigned char *md); |
| |
| int MDC2_Init(MDC2_CTX *c); |
| int MDC2_Update(MDC2_CTX *c, const unsigned char *data, |
| unsigned long len); |
| int MDC2_Final(unsigned char *md, MDC2_CTX *c); |
| |
| =head1 DESCRIPTION |
| |
| 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 B<n> |
| bytes at B<d> and places it in B<md> (which must have space for |
| MDC2_DIGEST_LENGTH == 16 bytes of output). If B<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 B<MDC2_CTX> structure. |
| |
| MDC2_Update() can be called repeatedly with chunks of the message to |
| be hashed (B<len> bytes at B<data>). |
| |
| MDC2_Final() places the message digest in B<md>, which must have space |
| for MDC2_DIGEST_LENGTH == 16 bytes of output, and erases the B<MDC2_CTX>. |
| |
| Applications should use the higher level functions |
| L<EVP_DigestInit(3)|EVP_DigestInit(3)> etc. instead of calling the |
| hash functions directly. |
| |
| =head1 RETURN VALUES |
| |
| MDC2() returns a pointer to the hash value. |
| |
| MDC2_Init(), MDC2_Update() and MDC2_Final() return 1 for success, 0 otherwise. |
| |
| =head1 CONFORMING TO |
| |
| ISO/IEC 10118-2, with DES |
| |
| =head1 SEE ALSO |
| |
| L<sha(3)|sha(3)>, L<EVP_DigestInit(3)|EVP_DigestInit(3)> |
| |
| =head1 HISTORY |
| |
| MDC2(), MDC2_Init(), MDC2_Update() and MDC2_Final() are available since |
| SSLeay 0.8. |
| |
| =cut |
