コード例 #1
0
        public static void crypto_sign_keypair(byte[] pk, int pkoffset, byte[] sk, int skoffset, byte[] seed, int seedoffset)
        {
            GroupElementP3 A;
            int            i;

            Array.Copy(seed, seedoffset, sk, skoffset, 32);
            byte[] h = Sha512.Hash(sk, skoffset, 32);//ToDo: Remove alloc
            ScalarOperations.sc_clamp(h, 0);

            GroupOperations.ge_scalarmult_base(out A, h, 0);
            GroupOperations.ge_p3_tobytes(pk, pkoffset, ref A);

            for (i = 0; i < 32; ++i)
            {
                sk[skoffset + 32 + i] = pk[pkoffset + i];
            }
            CryptoBytes.Wipe(h);
        }
コード例 #2
0
        public static bool crypto_sign_verify(
            byte[] signature, int signatureOffset,
            byte[] message, int messageOffset, int messageLength,
            byte[] publicKey, int publicKeyOffset)
        {
            byte[]         h;
            byte[]         checkr = new byte[32];
            GroupElementP3 A;
            GroupElementP2 R;

            if ((signature[signatureOffset + 63] & 224) != 0)
            {
                return(false);
            }
            if (GroupOperations.ge_frombytes_negate_vartime(out A, publicKey, publicKeyOffset) != 0)
            {
                return(false);
            }

            var hasher = new Sha512();

            hasher.Update(signature, signatureOffset, 32);
            hasher.Update(publicKey, publicKeyOffset, 32);
            hasher.Update(message, messageOffset, messageLength);
            h = hasher.FinalizeHash();

            ScalarOperations.sc_reduce(h);

            var sm32 = new byte[32];//todo: remove allocation

            Array.Copy(signature, signatureOffset + 32, sm32, 0, 32);
            GroupOperations.ge_double_scalarmult_vartime(out R, h, ref A, sm32);
            GroupOperations.ge_tobytes(checkr, 0, ref R);
            var result = CryptoBytes.ConstantTimeEquals(checkr, 0, signature, signatureOffset, 32);

            CryptoBytes.Wipe(h);
            CryptoBytes.Wipe(checkr);
            return(result);
        }
コード例 #3
0
        public static void crypto_sign(
            byte[] sig, int sigoffset,
            byte[] m, int moffset, int mlen,
            byte[] sk, int skoffset)
        {
            byte[]         az, r, hram;
            GroupElementP3 R;
            var            hasher = new Sha512();
            {
                hasher.Update(sk, skoffset, 32);
                az = hasher.FinalizeHash();
                ScalarOperations.sc_clamp(az, 0);

                hasher.Init();
                hasher.Update(az, 32, 32);
                hasher.Update(m, moffset, mlen);
                r = hasher.FinalizeHash();

                ScalarOperations.sc_reduce(r);
                GroupOperations.ge_scalarmult_base(out R, r, 0);
                GroupOperations.ge_p3_tobytes(sig, sigoffset, ref R);

                hasher.Init();
                hasher.Update(sig, sigoffset, 32);
                hasher.Update(sk, skoffset + 32, 32);
                hasher.Update(m, moffset, mlen);
                hram = hasher.FinalizeHash();

                ScalarOperations.sc_reduce(hram);
                var s = new byte[32];                //todo: remove allocation
                Array.Copy(sig, sigoffset + 32, s, 0, 32);
                ScalarOperations.sc_muladd(s, hram, az, r);
                Array.Copy(s, 0, sig, sigoffset + 32, 32);
                CryptoBytes.Wipe(s);
            }
        }
コード例 #4
0
        internal static void scalarmult(
            out FieldElement q,
            byte[] n, int noffset,
            ref FieldElement p)
        {
            byte[]       e = new byte[32];      //ToDo: remove allocation
            FieldElement x1, x2, x3;
            FieldElement z2, z3;
            FieldElement tmp0, tmp1;

            for (int i = 0; i < 32; ++i)
            {
                e[i] = n[noffset + i];
            }
            ScalarOperations.sc_clamp(e, 0);
            x1 = p;
            FieldOperations.fe_1(out x2);
            FieldOperations.fe_0(out z2);
            x3 = x1;
            FieldOperations.fe_1(out z3);

            uint swap = 0;

            for (int pos = 254; pos >= 0; --pos)
            {
                uint b = (uint)(e[pos / 8] >> (pos & 7));
                b    &= 1;
                swap ^= b;
                FieldOperations.fe_cswap(ref x2, ref x3, swap);
                FieldOperations.fe_cswap(ref z2, ref z3, swap);
                swap = b;

                /* qhasm: enter ladder */

                /* qhasm: D = X3-Z3 */
                /* asm 1: fe_sub(>D=fe#5,<X3=fe#3,<Z3=fe#4); */
                /* asm 2: fe_sub(>D=tmp0,<X3=x3,<Z3=z3); */
                FieldOperations.fe_sub(out tmp0, ref x3, ref z3);

                /* qhasm: B = X2-Z2 */
                /* asm 1: fe_sub(>B=fe#6,<X2=fe#1,<Z2=fe#2); */
                /* asm 2: fe_sub(>B=tmp1,<X2=x2,<Z2=z2); */
                FieldOperations.fe_sub(out tmp1, ref x2, ref z2);

                /* qhasm: A = X2+Z2 */
                /* asm 1: fe_add(>A=fe#1,<X2=fe#1,<Z2=fe#2); */
                /* asm 2: fe_add(>A=x2,<X2=x2,<Z2=z2); */
                FieldOperations.fe_add(out x2, ref x2, ref z2);

                /* qhasm: C = X3+Z3 */
                /* asm 1: fe_add(>C=fe#2,<X3=fe#3,<Z3=fe#4); */
                /* asm 2: fe_add(>C=z2,<X3=x3,<Z3=z3); */
                FieldOperations.fe_add(out z2, ref x3, ref z3);

                /* qhasm: DA = D*A */
                /* asm 1: fe_mul(>DA=fe#4,<D=fe#5,<A=fe#1); */
                /* asm 2: fe_mul(>DA=z3,<D=tmp0,<A=x2); */
                FieldOperations.fe_mul(out z3, ref tmp0, ref x2);

                /* qhasm: CB = C*B */
                /* asm 1: fe_mul(>CB=fe#2,<C=fe#2,<B=fe#6); */
                /* asm 2: fe_mul(>CB=z2,<C=z2,<B=tmp1); */
                FieldOperations.fe_mul(out z2, ref z2, ref tmp1);

                /* qhasm: BB = B^2 */
                /* asm 1: fe_sq(>BB=fe#5,<B=fe#6); */
                /* asm 2: fe_sq(>BB=tmp0,<B=tmp1); */
                FieldOperations.fe_sq(out tmp0, ref tmp1);

                /* qhasm: AA = A^2 */
                /* asm 1: fe_sq(>AA=fe#6,<A=fe#1); */
                /* asm 2: fe_sq(>AA=tmp1,<A=x2); */
                FieldOperations.fe_sq(out tmp1, ref x2);

                /* qhasm: t0 = DA+CB */
                /* asm 1: fe_add(>t0=fe#3,<DA=fe#4,<CB=fe#2); */
                /* asm 2: fe_add(>t0=x3,<DA=z3,<CB=z2); */
                FieldOperations.fe_add(out x3, ref z3, ref z2);

                /* qhasm: assign x3 to t0 */

                /* qhasm: t1 = DA-CB */
                /* asm 1: fe_sub(>t1=fe#2,<DA=fe#4,<CB=fe#2); */
                /* asm 2: fe_sub(>t1=z2,<DA=z3,<CB=z2); */
                FieldOperations.fe_sub(out z2, ref z3, ref z2);

                /* qhasm: X4 = AA*BB */
                /* asm 1: fe_mul(>X4=fe#1,<AA=fe#6,<BB=fe#5); */
                /* asm 2: fe_mul(>X4=x2,<AA=tmp1,<BB=tmp0); */
                FieldOperations.fe_mul(out x2, ref tmp1, ref tmp0);

                /* qhasm: E = AA-BB */
                /* asm 1: fe_sub(>E=fe#6,<AA=fe#6,<BB=fe#5); */
                /* asm 2: fe_sub(>E=tmp1,<AA=tmp1,<BB=tmp0); */
                FieldOperations.fe_sub(out tmp1, ref tmp1, ref tmp0);

                /* qhasm: t2 = t1^2 */
                /* asm 1: fe_sq(>t2=fe#2,<t1=fe#2); */
                /* asm 2: fe_sq(>t2=z2,<t1=z2); */
                FieldOperations.fe_sq(out z2, ref z2);

                /* qhasm: t3 = a24*E */
                /* asm 1: fe_mul121666(>t3=fe#4,<E=fe#6); */
                /* asm 2: fe_mul121666(>t3=z3,<E=tmp1); */
                FieldOperations.fe_mul121666(out z3, ref tmp1);

                /* qhasm: X5 = t0^2 */
                /* asm 1: fe_sq(>X5=fe#3,<t0=fe#3); */
                /* asm 2: fe_sq(>X5=x3,<t0=x3); */
                FieldOperations.fe_sq(out x3, ref x3);

                /* qhasm: t4 = BB+t3 */
                /* asm 1: fe_add(>t4=fe#5,<BB=fe#5,<t3=fe#4); */
                /* asm 2: fe_add(>t4=tmp0,<BB=tmp0,<t3=z3); */
                FieldOperations.fe_add(out tmp0, ref tmp0, ref z3);

                /* qhasm: Z5 = X1*t2 */
                /* asm 1: fe_mul(>Z5=fe#4,x1,<t2=fe#2); */
                /* asm 2: fe_mul(>Z5=z3,x1,<t2=z2); */
                FieldOperations.fe_mul(out z3, ref x1, ref z2);

                /* qhasm: Z4 = E*t4 */
                /* asm 1: fe_mul(>Z4=fe#2,<E=fe#6,<t4=fe#5); */
                /* asm 2: fe_mul(>Z4=z2,<E=tmp1,<t4=tmp0); */
                FieldOperations.fe_mul(out z2, ref tmp1, ref tmp0);

                /* qhasm: return */
            }
            FieldOperations.fe_cswap(ref x2, ref x3, swap);
            FieldOperations.fe_cswap(ref z2, ref z3, swap);

            FieldOperations.fe_invert(out z2, ref z2);
            FieldOperations.fe_mul(out x2, ref x2, ref z2);
            q = x2;
            CryptoBytes.Wipe(e);
        }