NAME
MD2, 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>
unsigned
char *MD2(const unsigned char *d, unsigned long n, unsigned char
*md);
void MD2_Init(MD2_CTX *c);
void MD2_Update(MD2_CTX
*c, const unsigned char *data, unsigned long len);
void
MD2_Final(unsigned char *md, MD2_CTX *c);
#include <openssl/md4.h>
unsigned
char *MD4(const unsigned char *d, unsigned long n, unsigned char
*md);
void MD4_Init(MD4_CTX *c);
void MD4_Update(MD4_CTX
*c, const void *data, unsigned long len);
void MD4_Final(unsigned
char *md, MD4_CTX *c);
#include <openssl/md5.h>
unsigned
char *MD5(const unsigned char *d, unsigned long n, unsigned char
*md);
void MD5_Init(MD5_CTX *c);
void MD5_Update(MD5_CTX
*c, const void *data, unsigned long len);
void MD5_Final(unsigned
char *md, MD5_CTX *c);
DESCRIPTION
MD2, 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.
NOTE
MD2, MD4, and MD5 are recommended only for compatibility with
existing applications. In new applications, SHA-1 or RIPEMD-160
should be preferred.
RETURN VALUES
MD2(), MD4(), and MD5() return pointers to the hash value.
MD2_Init(), MD2_Update(), MD2_Final(), MD4_Init(), MD4_Update(),
MD4_Final(), MD5_Init(), MD5_Update(), and MD5_Final() do not return
values.
CONFORMING TO
RFC 1319, RFC 1320, RFC 1321
SEE ALSO
sha(3), ripemd(3), EVP_DigestInit(3)
HISTORY
MD2(), MD2_Init(), MD2_Update() MD2_Final(), MD5(), MD5_Init(),
MD5_Update() and MD5_Final() are available in all versions of SSLeay
and OpenSSL.
MD4(), MD4_Init(), and MD4_Update() are available in OpenSSL
0.9.6 and above.