e56b2e5556
* fixes dynamic memory allocation test. previously a function called freeze() would trigger it
* this adds DilithiumII. Preprocessor conditionals still need to be removed
* fix ms Makefile
* fix MS compiler warnings
* clean-up
* remove preprocessor conditionals
* add dilithium3
* add dilithium4
* add duplicate consistency checks
* SHA2 state constants in common
* clean up symmetric.h
* Port SPHINCS+-SHA256 to sha256ctx struct
* Implement ctx struct for fips202
* Port Kyber{512,768,1024} to fips202 ctx struct
* Port NewHope to fips202 structs
* Port SPHINCS+-SHAKE256 to fips202 ctx structs
* Use opaque fips202 structs in MQDSS
* port dilithium to use fips202 ctx structs
* include -Wredundant-decls
* remove comment; format NTT constants
* reduce casts in power2round
75 lines
1.8 KiB
C
75 lines
1.8 KiB
C
#include "params.h"
|
|
#include "reduce.h"
|
|
#include <stdint.h>
|
|
|
|
/*************************************************
|
|
* Name: montgomery_reduce
|
|
*
|
|
* Description: For finite field element a with 0 <= a <= Q*2^32,
|
|
* compute r \equiv a*2^{-32} (mod Q) such that 0 <= r < 2*Q.
|
|
*
|
|
* Arguments: - uint64_t: finite field element a
|
|
*
|
|
* Returns r.
|
|
**************************************************/
|
|
uint32_t PQCLEAN_DILITHIUM2_CLEAN_montgomery_reduce(uint64_t a) {
|
|
uint64_t t;
|
|
|
|
t = a * QINV;
|
|
t &= (1ULL << 32) - 1;
|
|
t *= Q;
|
|
t = a + t;
|
|
t >>= 32;
|
|
return (uint32_t) t;
|
|
}
|
|
|
|
/*************************************************
|
|
* Name: reduce32
|
|
*
|
|
* Description: For finite field element a, compute r \equiv a (mod Q)
|
|
* such that 0 <= r < 2*Q.
|
|
*
|
|
* Arguments: - uint32_t: finite field element a
|
|
*
|
|
* Returns r.
|
|
**************************************************/
|
|
uint32_t PQCLEAN_DILITHIUM2_CLEAN_reduce32(uint32_t a) {
|
|
uint32_t t;
|
|
|
|
t = a & 0x7FFFFF;
|
|
a >>= 23;
|
|
t += (a << 13) - a;
|
|
return t;
|
|
}
|
|
|
|
/*************************************************
|
|
* Name: csubq
|
|
*
|
|
* Description: Subtract Q if input coefficient is bigger than Q.
|
|
*
|
|
* Arguments: - uint32_t: finite field element a
|
|
*
|
|
* Returns r.
|
|
**************************************************/
|
|
uint32_t PQCLEAN_DILITHIUM2_CLEAN_csubq(uint32_t a) {
|
|
a -= Q;
|
|
a += ((int32_t)a >> 31) & Q;
|
|
return a;
|
|
}
|
|
|
|
/*************************************************
|
|
* Name: freeze
|
|
*
|
|
* Description: For finite field element a, compute standard
|
|
* representative r = a mod Q.
|
|
*
|
|
* Arguments: - uint32_t: finite field element a
|
|
*
|
|
* Returns r.
|
|
**************************************************/
|
|
uint32_t PQCLEAN_DILITHIUM2_CLEAN_freeze(uint32_t a) {
|
|
a = PQCLEAN_DILITHIUM2_CLEAN_reduce32(a);
|
|
a = PQCLEAN_DILITHIUM2_CLEAN_csubq(a);
|
|
return a;
|
|
}
|