1.7

public/assets/sm/sm2_utils.js

@@ -0,0 +1,70 @@
+function decompressPublicKey(compressedKey) {
+    // 获取压缩标志和X坐标
+    var flag = compressedKey.slice(0, 2);
+    var x = compressedKey.slice(2);
+    
+    // 定义常量
+    var p = BigInt('0xFFFFFFFEFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF00000000FFFFFFFFFFFFFFFF', 16);
+    var a = BigInt('0xFFFFFFFEFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF00000000FFFFFFFFFFFFFFFC', 16);
+    var b = BigInt('0x28E9FA9E9D9F5E344D5A9E4BCF6509A7F39789F515AB8F92DDBCBD414D940E93', 16);
+    
+    // 计算Y坐标
+    // y2 = x3 + ax + b
+    var xBigInt = BigInt('0x' + x);
+    var alpha = (xBigInt ** 3n) % p;
+    var beta = (a * xBigInt + b) % p;
+    var y2 = (alpha + beta) % p;
+    var y = modularExponentiation(y2, (p + 1n) / 4n, p);
+    
+    // y2 的值开方有两个值，根据奇偶判定取哪一个
+    if (flag === "02") {
+        // 如果压缩标志为“02”，则Y坐标为偶数
+        if (y % 2n === 0n) {
+            return "04" + x + y.toString(16).padStart(64, '0');
+        } else {
+            y = p - y;
+            return "04" + x + y.toString(16).padStart(64, '0');
+        }
+    } else if (flag === "03") {
+        // 如果压缩标志为“03”，则Y坐标为奇数
+        if (y % 2n === 1n) {
+            return "04" + x + y.toString(16).padStart(64, '0');
+        } else {
+            y = p - y;
+            return "04" + x + y.toString(16).padStart(64, '0');
+        }
+    } else {
+        return null;
+    }
+}
+function modularExponentiation(base, exponent, modulus) {
+    var result = 1n;
+    base = base % modulus;
+    while (exponent > 0n) {
+        if (exponent % 2n === 1n) {
+            result = (result * base) % modulus;
+        }
+        base = (base * base) % modulus;
+        exponent = exponent / 2n;
+    }
+    return result;
+}
+function hexToBase64(hex) {
+    var bytes = [];
+    for (var i = 0; i < hex.length-1; i += 2) {
+        bytes.push(parseInt(hex.substr(i, 2), 16));
+    }
+    var byteArray = new Uint8Array(bytes);
+    return btoa(String.fromCharCode.apply(null, byteArray));
+}
+function base64ToHex(base64) {
+    var binaryString = atob(base64);
+    var byteArray = new Uint8Array(binaryString.length);
+    for (var i = 0; i < binaryString.length; i++) {
+        byteArray[i] = binaryString.charCodeAt(i);
+    }
+    var hexArray = Array.prototype.map.call(byteArray, function(byte) {
+        return ('0' + byte.toString(16)).slice(-2);
+    });
+    return hexArray.join('');
+}