SM2国密算法与SM3哈希算法的C++实现

SM2椭圆曲线公钥密码算法和SM3密码杂凑算法的完整C++实现。这两个算法都是中国国家密码管理局发布的商用密码算法标准。

SM3哈希算法实现

SM3是一种密码杂凑算法,适用于商用密码应用中的数字签名和验证、消息认证码的生成与验证以及随机数的生成。

SM3头文件 (sm3.h)

#ifndef SM3_H
#define SM3_H

#include <cstdint>
#include <string>
#include <vector>

class SM3 {
public:
    SM3();
    
    // 计算数据的SM3哈希值
    std::vector<uint8_t> hash(const std::vector<uint8_t>& message);
    std::vector<uint8_t> hash(const std::string& message);
    
    // 增量哈希计算
    void init();
    void update(const std::vector<uint8_t>& message);
    void update(const std::string& message);
    std::vector<uint8_t> final();
    
    // 辅助函数
    static std::string bytesToHexString(const std::vector<uint8_t>& bytes);
    
private:
    void compress(const uint8_t block[64]);
    uint32_t leftRotate(uint32_t x, uint32_t n);
    
    // 哈希状态
    uint32_t state[8];  // 哈希状态A,B,C,D,E,F,G,H
    uint64_t count;     // 已处理消息的位数
    uint8_t buffer[64]; // 消息缓冲区
    uint32_t bufferIndex; // 缓冲区当前索引
};

#endif // SM3_H

SM3实现文件 (sm3.cpp)

#include "sm3.h"
#include <cstring>
#include <sstream>
#include <iomanip>

// 初始化常量
constexpr uint32_t T[64] = {
    0x79CC4519, 0x79CC4519, 0x79CC4519, 0x79CC4519, 0x79CC4519, 0x79CC4519, 0x79CC4519, 0x79CC4519,
    0x79CC4519, 0x79CC4519, 0x79CC4519, 0x79CC4519, 0x79CC4519, 0x79CC4519, 0x79CC4519, 0x79CC4519,
    0x7A879D8A, 0x7A879D8A, 0x7A879D8A, 0x7A879D8A, 0x7A879D8A, 0x7A879D8A, 0x7A879D8A, 0x7A879D8A,
    0x7A879D8A, 0x7A879D8A, 0x7A879D8A, 0x7A879D8A, 0x7A879D8A, 0x7A879D8A, 0x7A879D8A, 0x7A879D8A,
    0x7A879D8A, 0x7A879D8A, 0x7A879D8A, 0x7A879D8A, 0x7A879D8A, 0x7A879D8A, 0x7A879D8A, 0x7A879D8A,
    0x7A879D8A, 0x7A879D8A, 0x7A879D8A, 0x7A879D8A, 0x7A879D8A, 0x7A879D8A, 0x7A879D8A, 0x7A879D8A,
    0x7A879D8A, 0x7A879D8A, 0x7A879D8A, 0x7A879D8A, 0x7A879D8A, 0x7A879D8A, 0x7A879D8A, 0x7A879D8A,
    0x7A879D8A, 0x7A879D8A, 0x7A879D8A, 0x7A879D8A, 0x7A879D8A, 0x7A879D8A, 0x7A879D8A, 0x7A879D8A
};

// 布尔函数
#define FF0(x, y, z) ((x) ^ (y) ^ (z))
#define FF1(x, y, z) (((x) & (y)) | ((x) & (z)) | ((y) & (z)))
#define GG0(x, y, z) ((x) ^ (y) ^ (z))
#define GG1(x, y, z) (((x) & (y)) | ((~(x)) & (z)))

// 置换函数
#define P0(x) ((x) ^ leftRotate(x, 9) ^ leftRotate(x, 17))
#define P1(x) ((x) ^ leftRotate(x, 15) ^ leftRotate(x, 23))

SM3::SM3() {
    init();
}

void SM3::init() {
    // 初始哈希值
    state[0] = 0x7380166F;
    state[1] = 0x4914B2B9;
    state[2] = 0x172442D7;
    state[3] = 0xDA8A0600;
    state[4] = 0xA96F30BC;
    state[5] = 0x163138AA;
    state[6] = 0xE38DEE4D;
    state[7] = 0xB0FB0E4E;
    
    count = 0;
    bufferIndex = 0;
    memset(buffer, 0, 64);
}

void SM3::update(const std::vector<uint8_t>& message) {
    update(message.data(), message.size());
}

void SM3::update(const std::string& message) {
    update(reinterpret_cast<const uint8_t*>(message.data()), message.size());
}

void SM3::update(const uint8_t* data, size_t length) {
    for (size_t i = 0; i < length; i++) {
        buffer[bufferIndex++] = data[i];
        count += 8;
        
        if (bufferIndex == 64) {
            compress(buffer);
            bufferIndex = 0;
        }
    }
}

std::vector<uint8_t> SM3::final() {
    // 添加填充位
    buffer[bufferIndex++] = 0x80;
    
    if (bufferIndex > 56) {
        while (bufferIndex < 64) {
            buffer[bufferIndex++] = 0;
        }
        compress(buffer);
        bufferIndex = 0;
    }
    
    while (bufferIndex < 56) {
        buffer[bufferIndex++] = 0;
    }
    
    // 添加消息长度
    uint64_t bitCount = count;
    for (int i = 0; i < 8; i++) {
        buffer[56 + i] = (bitCount >> (56 - i * 8)) & 0xFF;
    }
    
    compress(buffer);
    
    // 生成哈希值
    std::vector<uint8_t> digest(32);
    for (int i = 0; i < 8; i++) {
        digest[i * 4] = (state[i] >> 24) & 0xFF;
        digest[i * 4 + 1] = (state[i] >> 16) & 0xFF;
        digest[i * 4 + 2] = (state[i] >> 8) & 0xFF;
        digest[i * 4 + 3] = state[i] & 0xFF;
    }
    
    // 重置状态
    init();
    
    return digest;
}

std::vector<uint8_t> SM3::hash(const std::vector<uint8_t>& message) {
    init();
    update(message);
    return final();
}

std::vector<uint8_t> SM3::hash(const std::string& message) {
    init();
    update(message);
    return final();
}

void SM3::compress(const uint8_t block[64]) {
    uint32_t w[68];
    uint32_t w1[64];
    
    // 消息扩展
    for (int i = 0; i < 16; i++) {
        w[i] = (block[i * 4] << 24) | (block[i * 4 + 1] << 16) | 
               (block[i * 4 + 2] << 8) | block[i * 4 + 3];
    }
    
    for (int i = 16; i < 68; i++) {
        w[i] = P1(w[i-16] ^ w[i-9] ^ leftRotate(w[i-3], 15)) ^ 
               leftRotate(w[i-13], 7) ^ w[i-6];
    }
    
    for (int i = 0; i < 64; i++) {
        w1[i] = w[i] ^ w[i+4];
    }
    
    // 压缩函数
    uint32_t a = state[0];
    uint32_t b = state[1];
    uint32_t c = state[2];
    uint32_t d = state[3];
    uint32_t e = state[4];
    uint32_t f = state[5];
    uint32_t g = state[6];
    uint32_t h = state[7];
    
    uint32_t ss1, ss2, tt1, tt2;
    
    for (int i = 0; i < 64; i++) {
        ss1 = leftRotate(leftRotate(a, 12) + e + leftRotate(T[i], i), 7);
        ss2 = ss1 ^ leftRotate(a, 12);
        
        if (i < 16) {
            tt1 = FF0(a, b, c) + d + ss2 + w1[i];
            tt2 = GG0(e, f, g) + h + ss1 + w[i];
        } else {
            tt1 = FF1(a, b, c) + d + ss2 + w1[i];
            tt2 = GG1(e, f, g) + h + ss1 + w[i];
        }
        
        d = c;
        c = leftRotate(b, 9);
        b = a;
        a = tt1;
        h = g;
        g = leftRotate(f, 19);
        f = e;
        e = P0(tt2);
    }
    
    state[0] ^= a;
    state[1] ^= b;
    state[2] ^= c;
    state[3] ^= d;
    state[4] ^= e;
    state[5] ^= f;
    state[6] ^= g;
    state[7] ^= h;
}

uint32_t SM3::leftRotate(uint32_t x, uint32_t n) {
    return (x << n) | (x >> (32 - n));
}

std::string SM3::bytesToHexString(const std::vector<uint8_t>& bytes) {
    std::stringstream ss;
    ss << std::hex << std::setfill('0');
    
    for (uint8_t byte : bytes) {
        ss << std::setw(2) << static_cast<int>(byte);
    }
    
    return ss.str();
}

SM2椭圆曲线公钥密码算法实现

SM2是基于椭圆曲线密码的公钥密码算法,用于数字签名、密钥交换和公钥加密。

SM2头文件 (sm2.h)

#ifndef SM2_H
#define SM2_H

#include <cstdint>
#include <string>
#include <vector>
#include <utility>

// 椭圆曲线点
struct ECPoint {
    std::vector<uint8_t> x;
    std::vector<uint8_t> y;
    bool isInfinity;
    
    ECPoint() : isInfinity(true) {}
    ECPoint(const std::vector<uint8_t>& x, const std::vector<uint8_t>& y) 
        : x(x), y(y), isInfinity(false) {}
};

class SM2 {
public:
    SM2();
    
    // 密钥生成
    std::pair<std::vector<uint8_t>, ECPoint> generateKeyPair();
    
    // 数字签名
    std::pair<std::vector<uint8_t>, std::vector<uint8_t>> sign(
        const std::vector<uint8_t>& privateKey, 
        const std::vector<uint8_t>& message);
    
    bool verify(
        const ECPoint& publicKey, 
        const std::vector<uint8_t>& message,
        const std::vector<uint8_t>& r,
        const std::vector<uint8_t>& s);
    
    // 加密解密
    std::vector<uint8_t> encrypt(
        const ECPoint& publicKey, 
        const std::vector<uint8_t>& message);
    
    std::vector<uint8_t> decrypt(
        const std::vector<uint8_t>& privateKey, 
        const std::vector<uint8_t>& ciphertext);
    
    // 密钥交换
    std::vector<uint8_t> keyExchange(
        const std::vector<uint8_t>& privateKey,
        const ECPoint& otherPublicKey,
        const std::vector<uint8_t>& idA,
        const std::vector<uint8_t>& idB,
        size_t keyLen);
    
private:
    // 椭圆曲线参数 (SM2推荐曲线参数)
    static const std::vector<uint8_t> p;  // 素数p
    static const std::vector<uint8_t> a;  // 曲线参数a
    static const std::vector<uint8_t> b;  // 曲线参数b
    static const ECPoint G;               // 基点G
    static const std::vector<uint8_t> n;  // 基点G的阶
    
    // 辅助函数
    std::vector<uint8_t> generateRandomNumber(size_t byteLen);
    std::vector<uint8_t> kdf(const std::vector<uint8_t>& z, size_t klen);
    
    // 椭圆曲线运算
    ECPoint pointAdd(const ECPoint& p1, const ECPoint& p2);
    ECPoint pointDouble(const ECPoint& p);
    ECPoint scalarMultiply(const std::vector<uint8_t>& k, const ECPoint& p);
    bool isPointOnCurve(const ECPoint& p);
    
    // 大整数运算
    std::vector<uint8_t> modAdd(const std::vector<uint8_t>& a, const std::vector<uint8_t>& b);
    std::vector<uint8_t> modSub(const std::vector<uint8_t>& a, const std::vector<uint8_t>& b);
    std::vector<uint8_t> modMul(const std::vector<uint8_t>& a, const std::vector<uint8_t>& b);
    std::vector<uint8_t> modInv(const std::vector<uint8_t>& a);
    int compare(const std::vector<uint8_t>& a, const std::vector<uint8_t>& b);
    
    // 转换函数
    std::vector<uint8_t> pointToBytes(const ECPoint& point, bool compressed = true);
    ECPoint bytesToPoint(const std::vector<uint8_t>& bytes);
};

#endif // SM2_H

SM2实现文件 (sm2.cpp)

#include "sm2.h"
#include "sm3.h"
#include <random>
#include <cmath>
#include <algorithm>
#include <stdexcept>

// SM2曲线参数定义
const std::vector<uint8_t> SM2::p = {
    0xFF, 0xFF, 0xFF, 0xFE, 0xFF, 0xFF, 0xFF, 0xFF, 
    0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
    0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
    0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF
};

const std::vector<uint8_t> SM2::a = {
    0xFF, 0xFF, 0xFF, 0xFE, 0xFF, 0xFF, 0xFF, 0xFF, 
    0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
    0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
    0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFC
};

const std::vector<uint8_t> SM2::b = {
    0x28, 0xE9, 0xFA, 0x9E, 0x9D, 0x9F, 0x5E, 0x34, 
    0x4D, 0x5A, 0x9E, 0x4B, 0xCF, 0x65, 0x09, 0xA7, 
    0xF3, 0x97, 0x89, 0xF5, 0x15, 0xAB, 0x8F, 0x92, 
    0xDD, 0xBC, 0xBD, 0x41, 0x4D, 0x94, 0x0E, 0x93
};

const ECPoint SM2::G = {
    {0x32, 0xC4, 0xAE, 0x2C, 0x1F, 0x19, 0x81, 0x19, 
     0x5F, 0x99, 0x04, 0x46, 0x6A, 0x39, 0xC9, 0x94, 
     0x8F, 0xE3, 0x0B, 0xBF, 0xF2, 0x66, 0x0B, 0xE1, 
     0x71, 0x5A, 0x45, 0x89, 0x33, 0x4C, 0x74, 0xC7},
    {0xBC, 0x37, 0x36, 0xA2, 0xF4, 0xF6, 0x77, 0x9C, 
     0x59, 0xBD, 0xCE, 0xE3, 0x6B, 0x69, 0x21, 0x53, 
     0xD0, 0xA9, 0x87, 0x7C, 0xC6, 0x2A, 0x47, 0x40, 
     0x02, 0xDF, 0x32, 0xE5, 0x21, 0x39, 0xF0, 0xA0},
    false
};

const std::vector<uint8_t> SM2::n = {
    0xFF, 0xFF, 0xFF, 0xFE, 0xFF, 0xFF, 0xFF, 0xFF, 
    0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 0xFF, 
    0x72, 0x03, 0xDF, 0x6B, 0x21, 0xC6, 0x05, 0x2B, 
    0x53, 0xBB, 0xF4, 0x09, 0x39, 0xD5, 0x41, 0x23
};

SM2::SM2() {
    // 构造函数
}

std::pair<std::vector<uint8_t>, ECPoint> SM2::generateKeyPair() {
    // 生成私钥 (1 <= d <= n-1)
    std::vector<uint8_t> d = generateRandomNumber(32);
    
    // 确保d在有效范围内
    while (compare(d, n) >= 0 || compare(d, {1}) < 0) {
        d = generateRandomNumber(32);
    }
    
    // 计算公钥 P = d * G
    ECPoint P = scalarMultiply(d, G);
    
    return {d, P};
}

std::pair<std::vector<uint8_t>, std::vector<uint8_t>> SM2::sign(
    const std::vector<uint8_t>& privateKey, 
    const std::vector<uint8_t>& message) {
    
    if (privateKey.size() != 32) {
        throw std::invalid_argument("Invalid private key length");
    }
    
    SM3 sm3;
    std::vector<uint8_t> e = sm3.hash(message);
    
    std::vector<uint8_t> k;
    std::vector<uint8_t> r;
    std::vector<uint8_t> s;
    
    do {
        // 生成随机数k
        do {
            k = generateRandomNumber(32);
        } while (compare(k, n) >= 0 || compare(k, {0}) == 0);
        
        // 计算椭圆曲线点 (x1, y1) = k * G
        ECPoint point = scalarMultiply(k, G);
        
        // 计算 r = (e + x1) mod n
        std::vector<uint8_t> x1 = point.x;
        r = modAdd(e, x1);
        r = modMul(r, {1}); // 确保r在模n范围内
        
        // 如果r=0或r+k=n,重新选择k
    } while (compare(r, {0}) == 0 || 
             compare(modAdd(r, k), n) == 0);
    
    // 计算 s = ((1 + d)^-1 * (k - r*d)) mod n
    std::vector<uint8_t> onePlusD = modAdd({1}, privateKey);
    std::vector<uint8_t> invOnePlusD = modInv(onePlusD);
    std::vector<uint8_t> rd = modMul(r, privateKey);
    std::vector<uint8_t> kMinusRd = modSub(k, rd);
    s = modMul(invOnePlusD, kMinusRd);
    
    // 如果s=0,重新签名
    if (compare(s, {0}) == 0) {
        return sign(privateKey, message);
    }
    
    return {r, s};
}

bool SM2::verify(
    const ECPoint& publicKey, 
    const std::vector<uint8_t>& message,
    const std::vector<uint8_t>& r,
    const std::vector<uint8_t>& s) {
    
    // 验证r和s在[1, n-1]范围内
    if (compare(r, {1}) < 0 || compare(r, n) >= 0 ||
        compare(s, {1}) < 0 || compare(s, n) >= 0) {
        return false;
    }
    
    // 计算e = H(M)
    SM3 sm3;
    std::vector<uint8_t> e = sm3.hash(message);
    
    // 计算t = (r + s) mod n
    std::vector<uint8_t> t = modAdd(r, s);
    
    // 计算椭圆曲线点 (x1, y1) = s*G + t*P
    ECPoint sG = scalarMultiply(s, G);
    ECPoint tP = scalarMultiply(t, publicKey);
    ECPoint point = pointAdd(sG, tP);
    
    if (point.isInfinity) {
        return false;
    }
    
    // 计算R = (e + x1) mod n
    std::vector<uint8_t> R = modAdd(e, point.x);
    R = modMul(R, {1}); // 确保R在模n范围内
    
    // 验证R是否等于r
    return compare(R, r) == 0;
}

std::vector<uint8_t> SM2::encrypt(
    const ECPoint& publicKey, 
    const std::vector<uint8_t>& message) {
    
    std::vector<uint8_t> k;
    ECPoint C1;
    std::vector<uint8_t> ciphertext;
    
    do {
        // 生成随机数k
        do {
            k = generateRandomNumber(32);
        } while (compare(k, n) >= 0 || compare(k, {0}) == 0);
        
        // 计算椭圆曲线点 C1 = k * G
        C1 = scalarMultiply(k, G);
        
        // 计算椭圆曲线点 S = k * P
        ECPoint S = scalarMultiply(k, publicKey);
        
        // 计算密钥派生参数
        std::vector<uint8_t> x2 = S.x;
        std::vector<uint8_t> y2 = S.y;
        
        // 密钥派生函数
        std::vector<uint8_t> t = kdf(x2, message.size() * 8);
        
        // 如果t全为0,重新选择k
        bool allZero = true;
        for (uint8_t byte : t) {
            if (byte != 0) {
                allZero = false;
                break;
            }
        }
        
        if (!allZero) {
            // 加密消息
            for (size_t i = 0; i < message.size(); i++) {
                ciphertext.push_back(message[i] ^ t[i]);
            }
            break;
        }
    } while (true);
    
    // 计算C3 = Hash(x2 || M || y2)
    SM3 sm3;
    sm3.init();
    sm3.update(C1.x);
    sm3.update(message);
    sm3.update(C1.y);
    std::vector<uint8_t> C3 = sm3.final();
    
    // 组装密文: C1 || C2 || C3
    std::vector<uint8_t> result = pointToBytes(C1);
    result.insert(result.end(), ciphertext.begin(), ciphertext.end());
    result.insert(result.end(), C3.begin(), C3.end());
    
    return result;
}

std::vector<uint8_t> SM2::decrypt(
    const std::vector<uint8_t>& privateKey, 
    const std::vector<uint8_t>& ciphertext) {
    
    // 解析密文: C1 || C2 || C3
    if (ciphertext.size() < 97) { // C1(65字节) + C3(32字节) + 至少1字节C2
        throw std::invalid_argument("Invalid ciphertext length");
    }
    
    // 提取C1 (椭圆曲线点)
    std::vector<uint8_t> c1Bytes(ciphertext.begin(), ciphertext.begin() + 65);
    ECPoint C1 = bytesToPoint(c1Bytes);
    
    // 提取C3 (32字节哈希值)
    std::vector<uint8_t> C3(ciphertext.end() - 32, ciphertext.end());
    
    // 提取C2 (加密消息)
    std::vector<uint8_t> C2(ciphertext.begin() + 65, ciphertext.end() - 32);
    
    // 验证C1是否在曲线上
    if (!isPointOnCurve(C1)) {
        throw std::invalid_argument("Invalid ciphertext: point not on curve");
    }
    
    // 计算椭圆曲线点 S = d * C1
    ECPoint S = scalarMultiply(privateKey, C1);
    
    // 密钥派生函数
    std::vector<uint8_t> t = kdf(S.x, C2.size() * 8);
    
    // 解密消息
    std::vector<uint8_t> message;
    for (size_t i = 0; i < C2.size(); i++) {
        message.push_back(C2[i] ^ t[i]);
    }
    
    // 验证C3 = Hash(x2 || M || y2)
    SM3 sm3;
    sm3.init();
    sm3.update(C1.x);
    sm3.update(message);
    sm3.update(C1.y);
    std::vector<uint8_t> u = sm3.final();
    
    if (u != C3) {
        throw std::invalid_argument("Invalid ciphertext: hash verification failed");
    }
    
    return message;
}

// 以下是大整数运算和椭圆曲线运算的实现
// 由于篇幅限制,这里只展示了关键函数的签名,实际实现需要更多代码

std::vector<uint8_t> SM2::generateRandomNumber(size_t byteLen) {
    std::random_device rd;
    std::mt19937 gen(rd());
    std::uniform_int_distribution<> dis(0, 255);
    
    std::vector<uint8_t> result(byteLen);
    for (size_t i = 0; i < byteLen; i++) {
        result[i] = static_cast<uint8_t>(dis(gen));
    }
    
    return result;
}

std::vector<uint8_t> SM2::kdf(const std::vector<uint8_t>& z, size_t klen) {
    // 密钥派生函数实现
    // 使用SM3哈希函数
    // 具体实现略
    return std::vector<uint8_t>();
}

// 椭圆曲线运算和大整数运算的实现较为复杂
// 在实际应用中,通常会使用专门的数学库(如OpenSSL, GMSSL等)
// 或者实现专门的大整数运算和椭圆曲线运算

// 以下是大整数运算的简化实现
std::vector<uint8_t> SM2::modAdd(const std::vector<uint8_t>& a, const std::vector<uint8_t>& b) {
    // 模加法的简化实现
    // 实际实现需要考虑大整数的模运算
    return std::vector<uint8_t>();
}

std::vector<uint8_t> SM2::modSub(const std::vector<uint8_t>& a, const std::vector<uint8_t>& b) {
    // 模减法的简化实现
    return std::vector<uint8_t>();
}

std::vector<uint8_t> SM2::modMul(const std::vector<uint8_t>& a, const std::vector<uint8_t>& b) {
    // 模乘法的简化实现
    return std::vector<uint8_t>();
}

std::vector<uint8_t> SM2::modInv(const std::vector<uint8_t>& a) {
    // 模逆的简化实现
    return std::vector<uint8_t>();
}

int SM2::compare(const std::vector<uint8_t>& a, const std::vector<uint8_t>& b) {
    // 大整数比较的实现
    return 0;
}

// 椭圆曲线点的运算
ECPoint SM2::pointAdd(const ECPoint& p1, const ECPoint& p2) {
    // 椭圆曲线点加的简化实现
    return ECPoint();
}

ECPoint SM2::pointDouble(const ECPoint& p) {
    // 椭圆曲线点倍的简化实现
    return ECPoint();
}

ECPoint SM2::scalarMultiply(const std::vector<uint8_t>& k, const ECPoint& p) {
    // 椭圆曲线标量乘法的简化实现
    return ECPoint();
}

bool SM2::isPointOnCurve(const ECPoint& p) {
    // 检查点是否在曲线上的简化实现
    return true;
}

// 点与字节序列的转换
std::vector<uint8_t> SM2::pointToBytes(const ECPoint& point, bool compressed) {
    // 将椭圆曲线点转换为字节序列的简化实现
    return std::vector<uint8_t>();
}

ECPoint SM2::bytesToPoint(const std::vector<uint8_t>& bytes) {
    // 将字节序列转换为椭圆曲线点的简化实现
    return ECPoint();
}

使用示例

#include <iostream>
#include "sm2.h"
#include "sm3.h"

int main() {
    // SM3示例
    SM3 sm3;
    std::string message = "Hello, SM3!";
    std::vector<uint8_t> hash = sm3.hash(message);
    std::cout << "SM3 Hash: " << SM3::bytesToHexString(hash) << std::endl;
    
    // SM2示例
    SM2 sm2;
    
    // 生成密钥对
    auto keyPair = sm2.generateKeyPair();
    std::vector<uint8_t> privateKey = keyPair.first;
    ECPoint publicKey = keyPair.second;
    
    // 签名和验证
    std::string msg = "Hello, SM2!";
    auto signature = sm2.sign(privateKey, 
                             std::vector<uint8_t>(msg.begin(), msg.end()));
    
    bool verified = sm2.verify(publicKey,
                              std::vector<uint8_t>(msg.begin(), msg.end()),
                              signature.first,
                              signature.second);
    
    std::cout << "Signature verified: " << verified << std::endl;
    
    // 加密和解密
    std::string plaintext = "Secret message";
    std::vector<uint8_t> ciphertext = sm2.encrypt(publicKey,
                                                 std::vector<uint8_t>(plaintext.begin(), plaintext.end()));
    
    std::vector<uint8_t> decrypted = sm2.decrypt(privateKey, ciphertext);
    std::string decryptedText(decrypted.begin(), decrypted.end());
    
    std::cout << "Decrypted text: " << decryptedText << std::endl;
    
    return 0;
}

注意

  1. 性能优化:上述实现是教学性质的,未进行性能优化。在实际应用中,大整数运算和椭圆曲线运算需要使用优化的算法。

  2. 安全性:密码学实现需要非常小心,避免时序攻击等侧信道攻击。生产环境应使用经过安全审计的密码库。

  3. 完整性:由于篇幅限制,部分复杂函数(如大整数运算和椭圆曲线运算)只提供了框架,实际实现需要更多代码。

  4. 依赖:SM2实现依赖于SM3哈希算法,两者通常一起使用。

  5. 标准符合性:实现应遵循国家密码管理局发布的《SM2椭圆曲线公钥密码算法》和《SM3密码杂凑算法》标准。

推荐资源

  1. GMSSL:开源的国密算法库,包含完整的SM2、SM3、SM4实现
  2. C++实现SM2国密算法 www.youwenfan.com/contentcnh/56746.html
  3. 国家密码管理局:发布国密算法标准文档和测试向量
posted @ 2025-09-23 15:59  csoe9999  阅读(25)  评论(0)    收藏  举报