Add a command to do just Dilithium NTT

src/dilithium/wrapper.c

@@ -2,6 +2,7 @@
 #include "./params.h"
 #include "./api.h"
 #include "./sign.h"
+#include "./poly.h"
 #include <string.h>
 
 #if DILITHIUM_PUBLIC_KEY_SIZE != CRYPTO_PUBLICKEYBYTES
@@ -13,6 +14,9 @@
 #if DILITHIUM_SIGNATURE_SIZE != CRYPTO_BYTES
 #error invalid signature size, update me!
 #endif
+#if DILITHIUM_N != N
+#error invalid N, update me!
+#endif
 
 int getDilithiumAlgorithmVariant() {
 	return DILITHIUM_MODE;
@@ -39,3 +43,9 @@ int DilithiumState_sign(const DilithiumState* self, uint8_t* signature, const ui
 	size_t signatureSize = DILITHIUM_SIGNATURE_SIZE;
 	return crypto_sign_signature(signature, &signatureSize, message, DILITHIUM_MESSAGE_SIZE, self->m_sk);
 }
+
+int Dilithium_ntt(uint32_t* coefficients) {
+	poly* coeffs = (poly*)coefficients;
+	poly_ntt(coeffs);
+	return 0;
+}

src/dilithium/wrapper.h

@@ -8,6 +8,7 @@
 #define DILITHIUM_PRIVATE_KEY_SIZE 4016
 #define DILITHIUM_SIGNATURE_SIZE 3293
 #define DILITHIUM_MESSAGE_SIZE 16
+#define DILITHIUM_N 256
 #define DILITHIUM_SIGNED_MESSAGE_SIZE (DILITHIUM_SIGNATURE_SIZE + DILITHIUM_MESSAGE_SIZE)
 
 /**
@@ -79,4 +80,14 @@ int DilithiumState_verify(const DilithiumState* self, uint8_t *signedMessage);
  */
 int DilithiumState_sign(const DilithiumState* self, uint8_t* signature, const uint8_t* message);
 
+///
+/// @brief        Perform a forward NTT.
+///
+/// @param[inout] coefficients  Buffer of polynomial coefficients in integer
+///                             domain. The computation is done in-place, and
+///                             this array contains the coefficients in the
+///                             frequency domain after this function returns.
+///
+int Dilithium_ntt(uint32_t *coefficients);
+
 #endif // _DILITHIUM_WRAPPER_H_

src/main.c

@@ -298,6 +298,17 @@ int main(void) {
 				break;
 			}
 
+			case CMD_SW_DILITHIUM_NTT: {
+				int32_t polynomialBuffer[DILITHIUM_N];
+				// Receive the polynomial coefficients.
+				get_bytes(sizeof(int32_t)*DILITHIUM_N, (uint8_t*)polynomialBuffer);
+				BEGIN_INTERESTING_STUFF;
+				Dilithium_ntt(polynomialBuffer);
+				END_INTERESTING_STUFF;
+				// No reply is sent.
+				break;
+			}
+
 			case CMD_SW_KYBER512_SET_PUBLIC_AND_PRIVATE_KEY: {
 				// Receive the input parameters and handle the request.
 				get_bytes(KYBER512_PUBLIC_KEY_SIZE, Kyber512State_getPublicKey(&kyber512));

src/main.h

@@ -216,6 +216,15 @@
 ///   16-bit unsigned integer in little endian order that contains the private key size
 #define CMD_SW_DILITHIUM_GET_KEY_SIZES 0x94
 
+/// Perform Dilithium NTT.
+///
+/// Expected Input:
+///   A total of DILITHIUM_N 32-bit integers in little endian order.
+///
+/// Output:
+///   No reply is sent back.
+#define CMD_SW_DILITHIUM_NTT 0x9A
+
 #define CMD_SWDES_ENC_MISALIGNED 0x14
 #define CMD_SWAES128_ENC_MISALIGNED 0x1E
 #define CMD_SWDES_ENC_DUMMYROUNDS 0x15