NAME    [Toc]    [Back]

       md5,  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    [Toc]    [Back]

       #include <openssl/md2.h>

       unsigned char *MD2(
               const   unsigned   char   *d,   unsigned  long  n,
       unsigned char *md ); void MD2_Init(
               MD2_CTX *c ); void MD2_Update(
               MD2_CTX   *c,   const   unsigned    char    *data,
       unsigned long len ); void 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 ); void MD4_Init(
               MD4_CTX *c ); void MD4_Update(
               MD4_CTX *c, const void *data, unsigned long len );
       void 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 ); void MD5_Init(
               MD5_CTX *c ); void MD5_Update(
               MD5_CTX *c, const void *data, unsigned long len );
       void MD5_Final(
               unsigned char *md, MD5_CTX *c );

DESCRIPTION    [Toc]    [Back]

       MD2,  MD4, and MD5 are cryptographic hash functions with a
       128 bit output.

       The MD2(), MD4(), and MD5()  functions  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:

       The MD2_Init() function initializes a MD2_CTX structure.

       The MD2_Update() function can be  called  repeatedly  with
       chunks of the message to be hashed (len bytes at data).

       The  MD2_Final() function places the message digest in md,
       which must have space for MD2_DIGEST_LENGTH == 16 bytes of
       output, and erases the MD2_CTX.

       The  MD4_Init(),  MD4_Update(),  MD4_Final(),  MD5_Init(),
       MD5_Update(),  and  MD5_Final()  functions  are  analogous
       using an MD4_CTX and MD5_CTX structure.

       Applications  should  use the higher level functions, such
       as EVP_DigestInit(), instead of calling the hash functions
       directly.

       MD2,  MD4,  and MD5 conform to RFC 1319, RFC 1320, and RFC
       1321.

NOTES    [Toc]    [Back]

       MD2, MD4, and MD5 are recommended only  for  compatibility
       with  existing applications. In new applications, SHA-1 or
       RIPEMD-160 are preferred.

RETURN VALUES    [Toc]    [Back]

       The MD2(), MD4(), and MD5() functions return  pointers  to
       the hash value.

       The  MD2_Init(),  MD2_Update(),  MD2_Final(),  MD4_Init(),
       MD4_Update(), MD4_Final(), MD5_Init(),  MD5_Update(),  and
       MD5_Final() functions do not return values.

HISTORY    [Toc]    [Back]

       The  MD2(), MD2_Init(), MD2_Update(), MD2_Final()), MD5(),
       MD5_Init(), MD5_Update(), and  MD5_Final()  functions  are
       available in all versions of SSLeay and OpenSSL.

       The  MD4(),  MD4_Init(),  and  MD4_Update()  functions are
       available in OpenSSL 0.9.6 and above.

SEE ALSO    [Toc]    [Back]

       Functions: sha(3), ripemd(3), EVP_DigestInit(3)



                                                           md5(3)