Data commit

Task/Main-step-of-GOST-28147-89/JavaScript/main-step-of-gost-28147-89.js

@@ -0,0 +1,31 @@
+const Таблица_замен = [
+	[ 4, 10,  9,  2, 13,  8,  0, 14,  6, 11,  1, 12,  7, 15,  5,  3],
+	[14, 11,  4, 12,  6, 13, 15, 10,  2,  3,  8,  1,  0,  7,  5,  9],
+	[ 5,  8,  1, 13, 10,  3,  4,  2, 14, 15, 12,  7,  6,  0,  9, 11],
+	[ 7, 13, 10,  1,  0,  8,  9, 15, 14,  4,  6, 12, 11,  2,  5,  3],
+	[ 6, 12,  7,  1,  5, 15, 13,  8,  4, 10,  9, 14,  0,  3, 11,  2],
+	[ 4, 11, 10,  0,  7,  2,  1, 13,  3,  6,  8,  5,  9, 12, 15, 14],
+	[13, 11,  4,  1,  3, 15,  5,  9,  0, 10, 14,  7,  6,  8,  2, 12],
+	[ 1, 15, 13,  0,  5,  7, 10,  4,  9,  2,  3, 14,  6, 11,  8, 12]
+];
+
+const Основной_шаг = (блок_текста, элемент_ключа, ТЗ) => {
+	const
+		N = блок_текста.slice(0),
+		S = N[0] + элемент_ключа & 0xFFFFFFFF;
+	let нов_S = 0;
+	for (let сч = 0; сч < 4; сч++) {
+		const яч = (S >>> (сч << 3)) & 0xFF;
+		нов_S +=
+			ТЗ[сч * 2][яч & 0x0F]
+			+ (ТЗ[сч * 2 + 1][яч >>> 4] << 4)
+			<< (сч << 3);
+	}
+	нов_S =
+		(нов_S << 11)
+		+ (нов_S >>> 21)
+		& 0xFFFFFFFF
+		^ N[1];
+	N[1] = N[0]; N[0] = нов_S;
+	return N;
+};