openssl/doc/crypto/md5.pod
Rich Salz 9b86974e0c Fix L<> content in manpages
L<foo|foo> is sub-optimal  If the xref is the same as the title,
which is what we do, then you only need L<foo>.  This fixes all
1457 occurrences in 349 files.  Approximately.  (And pod used to
need both.)

Reviewed-by: Richard Levitte <levitte@openssl.org>
2015-08-21 15:11:50 -04:00

92 lines
2.5 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)>
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)>
=cut