1=pod 2 3=head1 NAME 4 5MD2, MD4, MD5, MD2_Init, MD2_Update, MD2_Final, MD4_Init, MD4_Update, 6MD4_Final, MD5_Init, MD5_Update, MD5_Final - MD2, MD4, and MD5 hash functions 7 8=head1 SYNOPSIS 9 10The following functions have been deprecated since OpenSSL 3.0, and can be 11hidden entirely by defining B<OPENSSL_API_COMPAT> with a suitable version value, 12see L<openssl_user_macros(7)>: 13 14 #include <openssl/md2.h> 15 16 unsigned char *MD2(const unsigned char *d, unsigned long n, unsigned char *md); 17 18 int MD2_Init(MD2_CTX *c); 19 int MD2_Update(MD2_CTX *c, const unsigned char *data, unsigned long len); 20 int MD2_Final(unsigned char *md, MD2_CTX *c); 21 22 23The following functions have been deprecated since OpenSSL 3.0, and can be 24hidden entirely by defining B<OPENSSL_API_COMPAT> with a suitable version value, 25see L<openssl_user_macros(7)>: 26 27 #include <openssl/md4.h> 28 29 unsigned char *MD4(const unsigned char *d, unsigned long n, unsigned char *md); 30 31 int MD4_Init(MD4_CTX *c); 32 int MD4_Update(MD4_CTX *c, const void *data, unsigned long len); 33 int MD4_Final(unsigned char *md, MD4_CTX *c); 34 35The following functions have been deprecated since OpenSSL 3.0, and can be 36hidden entirely by defining B<OPENSSL_API_COMPAT> with a suitable version value, 37see L<openssl_user_macros(7)>: 38 39 #include <openssl/md5.h> 40 41 unsigned char *MD5(const unsigned char *d, unsigned long n, unsigned char *md); 42 43 int MD5_Init(MD5_CTX *c); 44 int MD5_Update(MD5_CTX *c, const void *data, unsigned long len); 45 int MD5_Final(unsigned char *md, MD5_CTX *c); 46 47=head1 DESCRIPTION 48 49All of the functions described on this page are deprecated. 50Applications should instead use L<EVP_DigestInit_ex(3)>, L<EVP_DigestUpdate(3)> 51and L<EVP_DigestFinal_ex(3)>. 52 53MD2, MD4, and MD5 are cryptographic hash functions with a 128 bit output. 54 55MD2(), MD4(), and MD5() compute the MD2, MD4, and MD5 message digest 56of the B<n> bytes at B<d> and place it in B<md> (which must have space 57for MD2_DIGEST_LENGTH == MD4_DIGEST_LENGTH == MD5_DIGEST_LENGTH == 16 58bytes of output). If B<md> is NULL, the digest is placed in a static 59array. 60 61The following functions may be used if the message is not completely 62stored in memory: 63 64MD2_Init() initializes a B<MD2_CTX> structure. 65 66MD2_Update() can be called repeatedly with chunks of the message to 67be hashed (B<len> bytes at B<data>). 68 69MD2_Final() places the message digest in B<md>, which must have space 70for MD2_DIGEST_LENGTH == 16 bytes of output, and erases the B<MD2_CTX>. 71 72MD4_Init(), MD4_Update(), MD4_Final(), MD5_Init(), MD5_Update(), and 73MD5_Final() are analogous using an B<MD4_CTX> and B<MD5_CTX> structure. The parameter B<MUST NOT> be NULL. 74 75Applications should use the higher level functions 76L<EVP_DigestInit(3)> 77etc. instead of calling the hash functions directly. 78 79=head1 NOTE 80 81MD2, MD4, and MD5 are recommended only for compatibility with existing 82applications. In new applications, hashes from the SHA-2 or SHA-3 family 83should be preferred. 84 85=head1 RETURN VALUES 86 87MD2(), MD4(), and MD5() return pointers to the hash value. 88 89MD2_Init(), MD2_Update(), MD2_Final(), MD4_Init(), MD4_Update(), 90MD4_Final(), MD5_Init(), MD5_Update(), and MD5_Final() return 1 for 91success, 0 otherwise. 92 93=head1 CONFORMING TO 94 95RFC 1319, RFC 1320, RFC 1321 96 97=head1 SEE ALSO 98 99L<EVP_DigestInit(3)>, L<EVP_MD-SHA2(7)>, L<EVP_MD-SHA3(7)> 100 101=head1 HISTORY 102 103All of these functions were deprecated in OpenSSL 3.0. 104 105=head1 COPYRIGHT 106 107Copyright 2000-2024 The OpenSSL Project Authors. All Rights Reserved. 108 109Licensed under the Apache License 2.0 (the "License"). You may not use 110this file except in compliance with the License. You can obtain a copy 111in the file LICENSE in the source distribution or at 112L<https://www.openssl.org/source/license.html>. 113 114=cut 115
