MDC2_Init.3ossl - Man Page

MDC2 hash function


 #include <openssl/mdc2.h>

The following functions have been deprecated since OpenSSL 3.0, and can be hidden entirely by defining OPENSSL_API_COMPAT with a suitable version value, see openssl_user_macros(7):

 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);


All of the functions described on this page are deprecated. Applications should instead use EVP_DigestInit_ex(3), EVP_DigestUpdate(3) and EVP_DigestFinal_ex(3).

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

MDC2() returns a pointer to the hash value.

MDC2_Init(), MDC2_Update() and MDC2_Final() return 1 for success, 0 otherwise.

Conforming to

ISO/IEC 10118-2:2000 Hash-Function 2, with DES as the underlying block cipher.

See Also



All of these functions were deprecated in OpenSSL 3.0.

Referenced By

The man pages MDC2.3ossl(3), MDC2_Final.3ossl(3) and MDC2_Update.3ossl(3) are aliases of MDC2_Init.3ossl(3).

2023-10-26 3.1.4 OpenSSL