openssl/doc/crypto/md5.pod
Rich Salz c7497f34fb RT1665,2300: Crypto doc cleanups
RT1665: aes documentation.

Paul Green wrote a nice aes.pod file.
But we now encourage the EVP interface.
So I took his RT item and used it as impetus to add
the AES modes to EVP_EncryptInit.pod
I also noticed that rc4.pod has spurious references to some other
cipher pages, so I removed them.

RT2300: Clean up MD history (merged into RT1665)

Put HISTORY section only in EVP_DigestInit.pod. Also add words
to discourage use of older cipher-specific API, and remove SEE ALSO
links that point to them.

Make sure digest pages have a NOTE that says use EVP_DigestInit.

Review feedback:
More cleanup in EVP_EncryptInit.pod
Fixed SEE ALSO links in ripemd160.pod, sha.pod, mdc2.pod, blowfish.pod,
rc4.d, and des.pod.  Re-order sections in des.pod for consistency

Reviewed-by: Matt Caswell <matt@openssl.org>
2014-08-28 18:55:50 -04:00

92 lines
2.6 KiB
Text

=pod
=head1 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
=head1 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);
=head1 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 B<n> bytes at B<d> and place it in B<md> (which must have space
for MD2_DIGEST_LENGTH == MD4_DIGEST_LENGTH == MD5_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:
MD2_Init() initializes a B<MD2_CTX> structure.
MD2_Update() can be called repeatedly with chunks of the message to
be hashed (B<len> bytes at B<data>).
MD2_Final() places the message digest in B<md>, which must have space
for MD2_DIGEST_LENGTH == 16 bytes of output, and erases the B<MD2_CTX>.
MD4_Init(), MD4_Update(), MD4_Final(), MD5_Init(), MD5_Update(), and
MD5_Final() are analogous using an B<MD4_CTX> and B<MD5_CTX> structure.
Applications should use the higher level functions
L<EVP_DigestInit(3)|EVP_DigestInit(3)>
etc. instead of calling the hash functions directly.
=head1 NOTE
MD2, MD4, and MD5 are recommended only for compatibility with existing
applications. In new applications, SHA-1 or RIPEMD-160 should be
preferred.
=head1 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.
=head1 CONFORMING TO
RFC 1319, RFC 1320, RFC 1321
=head1 SEE ALSO
L<EVP_DigestInit(3)|EVP_DigestInit(3)>
=cut