HP Open Source Security for OpenVMS Volume 2: HP SSL for OpenVMS > CRYPTO Application
Programming Interface (API) ReferenceMD2
NAMEMD2, MD4, MD5, MD2_Init, MD2_Update, MD2_Final, MD4_Init, MD4_Update, MD4_Final, MD5_Init, MD5_Update, MD5_Final — MD2, MD4, and MD5 hash functions Synopsis#include <openssl/md2.h> DESCRIPTIONMD2, MD4, and MD5 are cryptographic hash functions with a 128 bit output. MD2(), MD4(), and MD5() compute the MD2, MD4, and MD5 message digest of the n bytes at d and place it in md (which must have space for MD2_DIGEST_LENGTH == MD4_DIGEST_LENGTH == MD5_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: MD2_Init() initializes a MD2_CTX structure. MD2_Update() can be called repeatedly with chunks of the message to be hashed (len bytes at data). MD2_Final() places the message digest in md, which must have space for MD2_DIGEST_LENGTH == 16 bytes of output, and erases the MD2_CTX. MD4_Init(), MD4_Update(), MD4_Final(), MD5_Init(), MD5_Update(), and MD5_Final() are analogous using an MD4_CTX and MD5_CTX structure. Applications should use the higher level functions EVP_DigestInit(3) etc. instead of calling the hash functions directly. NOTEMD2, MD4, and MD5 are recommended only for compatibility with existing applications. In new applications, SHA-1 or RIPEMD-160 should be preferred. |