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);
int MD2_Init(MD2_CTX *c);
int MD2_Update(MD2_CTX *c, const unsigned char *data,
unsigned long len);
int 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);
int MD4_Init(MD4_CTX *c);
int MD4_Update(MD4_CTX *c, const void *data,
unsigned long len);
int 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);
int MD5_Init(MD5_CTX *c);
int MD5_Update(MD5_CTX *c, const void *data,
unsigned long len);
int 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() return 1 for success, 0 otherwise.
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.