gnu.crypto.key.dss
public class FIPS186 extends Object
An implementation of the DSA parameters generation as described in FIPS-186.
References:Version: $Revision: 1.2 $
Field Summary | |
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static int | DSA_PARAMS_COUNTER |
static int | DSA_PARAMS_E |
static int | DSA_PARAMS_G |
static int | DSA_PARAMS_P |
static int | DSA_PARAMS_Q |
static int | DSA_PARAMS_SEED |
Constructor Summary | |
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FIPS186(int L, SecureRandom rnd) |
Method Summary | |
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BigInteger[] | generateParameters()
This method generates the DSS p , q , and
g parameters only when L (the modulus length)
is not one of the following: 512 , 768 and
1024 . |
p
, q
, and
g
parameters only when L
(the modulus length)
is not one of the following: 512
, 768
and
1024
. For those values of L
, this implementation
uses pre-computed values of p
, q
, and
g
given in the document CryptoSpec included in the
security guide documentation of the standard JDK distribution.
The DSS requires two primes , p
and q
,
satisfying the following three conditions:
2159 < q < 2160
2L-1 < p < 2L
for a
specified L
, where L = 512 + 64j
for some
0 <= j <= 8
q
, in the range 2159 < q
< 2160. Once this is accomplished, the same SEED
value is used to construct an X
in the range 2L-1
< X < 2L. The prime, p
, is then
formed by rounding X
to a number congruent to 1 mod
2q
. In this implementation we use the same SEED value given
in FIPS-186, Appendix 5.