protected override BigInteger GenerateSearchBase (int bits, object Context)
{
if (Context == null) throw new ArgumentNullException ("Context");
BigInteger ret = new BigInteger ((BigInteger)Context);
ret.setBit (0);
return ret;
}
protected virtual BigInteger GenerateSearchBase(int bits, object Context)
{
BigInteger ret = BigInteger.genRandom(bits);
ret.setBit(0);
return(ret);
}
protected override BigInteger GenerateSearchBase(int bits, object Context)
{
if (Context == null)
{
throw new ArgumentNullException("Context");
}
BigInteger ret = new BigInteger((BigInteger)Context);
ret.setBit(0);
return(ret);
}
private BigInteger GenerateOddNumber(uint nBits)
{
var result = new BigInteger();
var random = new Random();
for (uint i = 0; i < nBits; i++)
{
if (random.Next(2) == 1)
{
result.setBit(i);
}
}
// ensures the bigint is odd
result.setBit(0);
// ensures ns high bit is set
result.setBit(nBits - 1);
result.setBit(nBits - 2);
return(result);
}
protected override BigInteger GenerateSearchBase(int bits, object Context)
{
BigInteger ret = base.GenerateSearchBase(bits, Context);
ContextData ctx = (ContextData)Context;
Assert.AreEqual(ctx.bits, bits);
uint d = ctx.testData;
for (uint i = (uint)bits - 2; d > 0; i--, d >>= 1)
{
ret.setBit(i, (d & 1) == 1);
}
return(ret);
}
private static BigInteger[] findRandomStrongPrime(uint primeBits, int orderBits, Rng random)
{
BigInteger one = new BigInteger(1);
BigInteger u, aux, aux2;
long[] table_q, table_u, prime_table;
PrimeSieve sieve = new PrimeSieve(16000);
uint table_count = sieve.AvailablePrimes() - 1;
int i, j;
bool flag;
BigInteger prime = null, order = null;
order = BigInteger.genPseudoPrime(orderBits, 20, random);
prime_table = new long[table_count];
table_q = new long[table_count];
table_u = new long[table_count];
i = 0;
for (int pN = 2; pN != 0; pN = sieve.getNextPrime(pN), i++)
{
prime_table[i] = (long)pN;
}
for (i = 0; i < table_count; i++)
{
table_q[i] =
(((order % new BigInteger(prime_table[i])).LongValue()) *
(long)2) % prime_table[i];
}
while (true)
{
u = new BigInteger();
u.genRandomBits((int)primeBits, random);
u.setBit(primeBits - 1);
aux = order << 1;
aux2 = u % aux;
u = u - aux2;
u = u + one;
if (u.bitCount() <= (primeBits - 1))
{
continue;
}
for (j = 0; j < table_count; j++)
{
table_u[j] =
(u % new BigInteger(prime_table[j])).LongValue();
}
aux2 = order << 1;
for (i = 0; i < (1 << 24); i++)
{
long cur_p;
long value;
flag = true;
for (j = 1; j < table_count; j++)
{
cur_p = prime_table[j];
value = table_u[j];
if (value >= cur_p)
{
value -= cur_p;
}
if (value == 0)
{
flag = false;
}
table_u[j] = value + table_q[j];
}
if (!flag)
{
continue;
}
aux = aux2 * new BigInteger(i);
prime = u + aux;
if (prime.bitCount() > primeBits)
{
continue;
}
if (prime.isProbablePrime(20))
{
break;
}
}
if (i < (1 << 24))
{
break;
}
}
return(new BigInteger[] { prime, order });
}
private static BigInteger[] findRandomStrongPrime(uint primeBits, int orderBits, Random random)
{
BigInteger one = new BigInteger(1);
BigInteger u, aux, aux2;
long[] table_q, table_u, prime_table;
PrimeSieve sieve = new PrimeSieve(16000);
uint table_count = sieve.AvailablePrimes() - 1;
int i, j;
bool flag;
BigInteger prime = null, order = null;
order = BigInteger.genPseudoPrime(orderBits, 20, random);
prime_table = new long[table_count];
table_q = new long[table_count];
table_u = new long[table_count];
i = 0;
for(int pN = 2; pN != 0; pN = sieve.getNextPrime(pN), i++) {
prime_table[i] = (long)pN;
}
for(i = 0; i < table_count; i++) {
table_q[i] =
(((order % new BigInteger(prime_table[i])).LongValue()) *
(long)2) % prime_table[i];
}
while(true) {
u = new BigInteger();
u.genRandomBits((int)primeBits, random);
u.setBit(primeBits - 1);
aux = order << 1;
aux2 = u % aux;
u = u - aux2;
u = u + one;
if(u.bitCount() <= (primeBits - 1))
continue;
for(j = 0; j < table_count; j++) {
table_u[j] =
(u % new BigInteger(prime_table[j])).LongValue();
}
aux2 = order << 1;
for(i = 0; i < (1 << 24); i++) {
long cur_p;
long value;
flag = true;
for(j = 1; j < table_count; j++) {
cur_p = prime_table[j];
value = table_u[j];
if(value >= cur_p)
value -= cur_p;
if(value == 0)
flag = false;
table_u[j] = value + table_q[j];
}
if(!flag)
continue;
aux = aux2 * new BigInteger(i);
prime = u + aux;
if(prime.bitCount() > primeBits)
continue;
if(prime.isProbablePrime(20))
break;
}
if(i < (1 << 24))
break;
}
return new BigInteger[] { prime, order };
}
