Manual Pages for UNIX Operating System command usage for man SHA1_Update

OpenSSL                                             sha(3openssl)



NNNNAAAAMMMMEEEE
     SHA1, SHA1_Init, SHA1_Update, SHA1_Final - Secure Hash
     Algorithm

SSSSYYYYNNNNOOOOPPPPSSSSIIIISSSS
      #include 

      unsigned char *SHA1(const unsigned char *d, unsigned long n,
                       unsigned char *md);

      int SHA1_Init(SHA_CTX *c);
      int SHA1_Update(SHA_CTX *c, const void *data,
                       unsigned long len);
      int SHA1_Final(unsigned char *md, SHA_CTX *c);


DDDDEEEESSSSCCCCRRRRIIIIPPPPTTTTIIIIOOOONNNN
     SHA-1 (Secure Hash Algorithm) is a cryptographic hash
     function with a 160 bit output.

     SHA1() computes the SHA-1 message digest of the nnnn bytes at dddd
     and places it in mmmmdddd (which must have space for
     SHA_DIGEST_LENGTH == 20 bytes of output). If mmmmdddd 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:

     SHA1_Init() initializes a SSSSHHHHAAAA_CCCCTTTTXXXX structure.

     SHA1_Update() can be called repeatedly with chunks of the
     message to be hashed (lllleeeennnn bytes at ddddaaaattttaaaa).

     SHA1_Final() places the message digest in mmmmdddd, which must
     have space for SHA_DIGEST_LENGTH == 20 bytes of output, and
     erases the SSSSHHHHAAAA_CCCCTTTTXXXX.

     Applications should use the higher level functions
     EVP_DigestInit(3) etc. instead of calling the hash functions
     directly.

     The predecessor of SHA-1, SHA, is also implemented, but it
     should be used only when backward compatibility is required.

RRRREEEETTTTUUUURRRRNNNN VVVVAAAALLLLUUUUEEEESSSS
     SHA1() returns a pointer to the hash value.

     SHA1_Init(), SHA1_Update() and SHA1_Final() return 1 for
     success, 0 otherwise.

CCCCOOOONNNNFFFFOOOORRRRMMMMIIIINNNNGGGG TTTTOOOO
     SHA: US Federal Information Processing Standard FIPS PUB 180



27/Oct/2006            Last change: 0.9.8o                      1






OpenSSL                                             sha(3openssl)



     (Secure Hash Standard), SHA-1: US Federal Information
     Processing Standard FIPS PUB 180-1 (Secure Hash Standard),
     ANSI X9.30

SSSSEEEEEEEE AAAALLLLSSSSOOOO
     ripemd(3), hmac(3), EVP_DigestInit(3)

HHHHIIIISSSSTTTTOOOORRRRYYYY
     SHA1(), SHA1_Init(), SHA1_Update() and SHA1_Final() are
     available in all versions of SSLeay and OpenSSL.













































27/Oct/2006            Last change: 0.9.8o                      2