MD5.3ossl - Man Page

MD2, MD4, and MD5 hash functions

Synopsis

 #include <openssl/md2.h>

The following functions have been deprecated since OpenSSL 3.0, and can be hidden entirely by defining OPENSSL_API_COMPAT with a suitable version value, see openssl_user_macros(7):

 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>

The following functions have been deprecated since OpenSSL 3.0, and can be hidden entirely by defining OPENSSL_API_COMPAT with a suitable version value, see openssl_user_macros(7):

 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>

The following functions have been deprecated since OpenSSL 3.0, and can be hidden entirely by defining OPENSSL_API_COMPAT with a suitable version value, see openssl_user_macros(7):

 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

All of the functions described on this page are deprecated. Applications should instead use EVP_DigestInit_ex(3), EVP_DigestUpdate(3) and EVP_DigestFinal_ex(3).

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, hashes from the SHA-2 or SHA-3 family 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.

Conforming to

RFC 1319, RFC 1320, RFC 1321

See Also

EVP_DigestInit(3), EVP_MD-SHA2(7), EVP_MD-SHA3(7)

History

All of these functions were deprecated in OpenSSL 3.0.

Referenced By

EVP_DigestSignInit.3ossl(3), EVP_DigestVerifyInit.3ossl(3), EVP_SignInit.3ossl(3), EVP_VerifyInit.3ossl(3).

The man pages MD2.3ossl(3), MD2_Final.3ossl(3), MD2_Init.3ossl(3), MD2_Update.3ossl(3), MD4.3ossl(3), MD4_Final.3ossl(3), MD4_Init.3ossl(3), MD4_Update.3ossl(3), MD5_Final.3ossl(3), MD5_Init.3ossl(3) and MD5_Update.3ossl(3) are aliases of MD5.3ossl(3).

2024-09-12 3.2.2 OpenSSL