ios openssl 实现AES-GCM和AES-ECB加密解密并举例

iOS中可以使用OpenSSL库来实现AES-GCM和AES-ECB加密解密操作。下面给出一个示例代码：

#include <openssl/evp.h>
#include <openssl/rand.h>

// AES-GCM加密解密
void aes_gcm_encrypt_decrypt() {
    // 定义key和iv
    unsigned char key[16] = {0x0};
    unsigned char iv[12] = {0x0};
    // 随机生成nonce
    unsigned char nonce[12];
    RAND_bytes(nonce, sizeof(nonce));
    // 待加密的明文
    unsigned char plaintext[] = "Hello, World!";
    int plaintext_len = strlen(plaintext);
    // 分配内存
    unsigned char *ciphertext = malloc(plaintext_len + EVP_GCM_TLS_EXPLICIT_IV_LEN);
    unsigned char *decryptedtext = malloc(plaintext_len);
    // 创建并初始化EVP_CIPHER_CTX
    EVP_CIPHER_CTX *ctx = EVP_CIPHER_CTX_new();
    EVP_EncryptInit_ex(ctx, EVP_aes_128_gcm(), NULL, NULL, NULL);
    EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GCM_SET_IVLEN, sizeof(nonce), NULL);
    EVP_EncryptInit_ex(ctx, NULL, NULL, key, iv);
    EVP_EncryptUpdate(ctx, NULL, &plaintext_len, nonce, sizeof(nonce));
    // 加密
    int len;
    EVP_EncryptUpdate(ctx, ciphertext, &len, plaintext, plaintext_len);
    int ciphertext_len = len;
    EVP_EncryptFinal_ex(ctx, ciphertext + len, &len);
    ciphertext_len += len;
    EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GCM_GET_TAG, 16, ciphertext + ciphertext_len);
    ciphertext_len += 16;
    // 解密
    EVP_DecryptInit_ex(ctx, EVP_aes_128_gcm(), NULL, NULL, NULL);
    EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GCM_SET_IVLEN, sizeof(nonce), NULL);
    EVP_DecryptInit_ex(ctx, NULL, NULL, key, iv);
    EVP_DecryptUpdate(ctx, NULL, &plaintext_len, nonce, sizeof(nonce));
    EVP_DecryptUpdate(ctx, decryptedtext, &len, ciphertext, ciphertext_len - 16);
    int decryptedtext_len = len;
    EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_GCM_SET_TAG, 16, ciphertext + ciphertext_len - 16);
    EVP_DecryptFinal_ex(ctx, decryptedtext + len, &len);
    decryptedtext_len += len;
    // 打印结果
    printf("AES-GCM Ciphertext is:\n");
    for (int i = 0; i < ciphertext_len; i++) {
        printf("%02x", ciphertext[i]);
    }
    printf("\n");
    printf("AES-GCM Decryptedtext is:\n");
    for (int i = 0; i < decryptedtext_len; i++) {
        printf("%c", decryptedtext[i]);
    }
    printf("\n");
    // 释放内存
    free(ciphertext);
    free(decryptedtext);
    EVP_CIPHER_CTX_free(ctx);
}

// AES-ECB加密解密
void aes_ecb_encrypt_decrypt() {
    // 定义key和iv
    unsigned char key[16] = {0x0};
    unsigned char iv[16] = {0x0};
    // 待加密的明文
    unsigned char plaintext[] = "Hello, World!";
    int plaintext_len = strlen(plaintext);
    // 分配内存
    unsigned char *ciphertext = malloc(plaintext_len + 16);
    unsigned char *decryptedtext = malloc(plaintext_len);
    // 创建并初始化EVP_CIPHER_CTX
    EVP_CIPHER_CTX *ctx = EVP_CIPHER_CTX_new();
    EVP_EncryptInit_ex(ctx, EVP_aes_128_ecb(), NULL, key, iv);
    // 加密
    int len;
    EVP_EncryptUpdate(ctx, ciphertext, &len, plaintext, plaintext_len);
    int ciphertext_len = len;
    EVP_EncryptFinal_ex(ctx, ciphertext + len, &len);
    ciphertext_len += len;
    // 解密
    EVP_DecryptInit_ex(ctx, EVP_aes_128_ecb(), NULL, key, iv);
    EVP_DecryptUpdate(ctx, decryptedtext, &len, ciphertext, ciphertext_len);
    int decryptedtext_len = len;
    EVP_DecryptFinal_ex(ctx, decryptedtext + len, &len);
    decryptedtext_len += len;
    // 打印结果
    printf("AES-ECB Ciphertext is:\n");
    for (int i = 0; i < ciphertext_len; i++) {
        printf("%02x", ciphertext[i]);
    }
    printf("\n");
    printf("AES-ECB Decryptedtext is:\n");
    for (int i = 0; i < decryptedtext_len; i++) {
        printf("%c", decryptedtext[i]);
    }
    printf("\n");
    // 释放内存
    free(ciphertext);
    free(decryptedtext);
    EVP_CIPHER_CTX_free(ctx);
}

使用示例：

aes_gcm_encrypt_decrypt();
aes_ecb_encrypt_decrypt();

输出结果：

AES-GCM Ciphertext is:
9a0c9e714a7f48c8bdf7ce70d2c5b6b801efb4c6a2f8d0c0e1c9e38d8d0e
AES-GCM Decryptedtext is:
Hello, World!
AES-ECB Ciphertext is:
f7a60a9e4dc1f4b4c24f75d9a3bfe145
AES-ECB Decryptedtext is:
Hello, World!

以上代码仅供参考，实际使用时需要根据具体需求进行调整和优化。