DSA_do_sign(3)              OpenSSL              DSA_do_sign(3)





NAME
       DSA_do_sign, DSA_do_verify - raw DSA signature opera-
       tions

SYNOPSIS
        #include <openssl/dsa.h>

        DSA_SIG *DSA_do_sign(const unsigned char *dgst, int dlen, DSA *dsa);

        int DSA_do_verify(const unsigned char *dgst, int dgst_len,
                    DSA_SIG *sig, DSA *dsa);

DESCRIPTION
       DSA_do_sign() computes a digital signature on the len
       byte message digest dgst using the private key dsa and
       returns it in a newly allocated DSA_SIG structure.

       DSA_sign_setup(3) may be used to precompute part of the
       signing operation in case signature generation is
       time-critical.

       DSA_do_verify() verifies that the signature sig matches
       a given message digest dgst of size len.  dsa is the
       signer's public key.

RETURN VALUES
       DSA_do_sign() returns the signature, NULL on error.
       DSA_do_verify() returns 1 for a valid signature, 0 for
       an incorrect signature and -1 on error. The error codes
       can be obtained by ERR_get_error(3).

SEE ALSO
       dsa(3), ERR_get_error(3), rand(3), DSA_SIG_new(3),
       DSA_sign(3)

HISTORY
       DSA_do_sign() and DSA_do_verify() were added in OpenSSL
       0.9.3.



0.9.7c                     2002-09-25            DSA_do_sign(3)
