JPakePrimeOrderGroup
A pre-computed prime order group for use during a J-PAKE exchange.
Typically a Schnorr group is used. In general, J-PAKE can use any prime order group
that is suitable for public key cryptography, including elliptic curve cryptography.
See JPakePrimeOrderGroups for convenient standard groups.
NIST publishes
many groups that can be used for the desired level of security.
Constructs a new JPakePrimeOrderGroup.
In general, you should use one of the pre-approved groups from
JPakePrimeOrderGroups, rather than manually constructing one.
The following basic checks are performed:
p-1 must be evenly divisible by q
g must be in [2, p-1]
g^q mod p must equal 1
p must be prime (within reasonably certainty)
q must be prime (within reasonably certainty)
The prime checks are performed using BigInteger#isProbablePrime(int),
and are therefore subject to the same probability guarantees.
These checks prevent trivial mistakes.
However, due to the small uncertainties if p and q are not prime,
advanced attacks are not prevented.
Use it at your own risk.
Throws NullReferenceException if any argument is null. Throws
InvalidOperationException is any of the above validations fail.
Constructor used by the pre-approved groups in JPakePrimeOrderGroups.
These pre-approved groups can avoid the expensive checks.
User-specified groups should not use this constructor.