Question

我缩进以验证服务器端实现的c或c ++中的'google inapp billing signature'

我找到了通过php的方式（Android in-app billing signature verification in php server）并建议它可以在openssl..but中使用EVP_Verify ...函数使用：

int EVP_VerifyFinal（EVP_MD_CTX * ctx，unsigned char * sigbuf，unsigned int siglen，EVP_PKEY * pkey）;

它需要'EVP_PKEY * pkey'结构的实例作为参数......但我没有它！

我相信将'Google InApp Billing签名字符串（base64编码SHA1-with-RAS签名与PKCS＃1填充）'转换为EVP_PKEY的方式。但我不知道该怎么做。

如何将其作为EVP_VerifyFinal函数的参数传递？

int main()
{
    OPENSSL_config(NULL);
    OpenSSL_add_all_digests();
    ERR_load_crypto_strings();

    EVP_MD_CTX* ctx = EVP_MD_CTX_create();
    const EVP_MD* md = EVP_get_digestbyname("SHA1");
    if(0 == EVP_VerifyInit_ex(ctx, md, NULL))
    {
        std::cerr << "init error" << std::endl;
        return 0;
    }

    const char* data = "{\"orderId\":\"12999763169054705758.1310724241212373\",\"packageName\":\"com.company.game.google\",\"productId\":\"game_product_001\",\"purchaseTime\":1358227642000,\"purchaseState\":0,\"developerPayload\":\"12322144\",\"purchaseToken\":\"}";
    if(0 == EVP_VerifyUpdate(ctx, (void*)data, strlen(data)))
    {
        std::cerr << "update error" << std::endl;
        return 0;
    }

    const char* key_context = "MIIBIjANBgkqhkiG9w0BAQEFAAOCAQ8AMIIBCgKCAQEAh0UDlUA1aYPvfRFq6qUjDVG/fi5EetC6LsjdT/WNmHUAy0muvuOTFfQEzBoELciDfh23VXgwVnb/XsfuvQrCgtnQbuMKsj+sDhofLjeq8TznEMlQcJ//0LsGSM8rRVHw72BYA2mSVKi04k1GIicB9J25c2f+eIwF7lEWJlWqVDlNqOS7GIIjnq3HPhqki3ZRSA9c";

    EVP_PKEY* pub_key = EVP_PKEY_new();
    if(NULL == pub_key)
    {
        std::cerr << "evp_pkey new error" << std::endl;
        return 0;
    }

    // I have to call 'EVP_VerifyFinish' here!! but I don't know how to!!
    ERR_remove_state(0);
    ERR_free_strings();

    return 0;
}

请有人帮助我!!

Answer 1

代码未经测试但应该是这样的：

BIO *mem= BIO_new(BIO_s_mem());
BIO_puts(mem, "your data");
RSA *cipher;
PEM_read_bio_RSAPublicKey(mem, &cipher, NULL, NULL);
EVP_PKEY *pkey  = EVP_PKEY_new();
EVP_PKEY_set1_RSA(pkey, cipher);

Answer 2

感谢您的回答.. 但是我在下面做了.. （它有效。我已经测试了!!）

PS。代码中的Base64Decode函数..你可以在互联网上找到很多来源..

int Verify_GoogleInappBilling_Signature(const char* data, const char* signature, const char* pub_key_id)
{
    std::shared_ptr<EVP_MD_CTX> mdctx = std::shared_ptr<EVP_MD_CTX>(EVP_MD_CTX_create(), EVP_MD_CTX_destroy);
    const EVP_MD* md = EVP_get_digestbyname("SHA1");
    if(NULL == md)
    {
        return -1;
    }
    if(0 == EVP_VerifyInit_ex(mdctx.get(), md, NULL))
    {
        return -1;
    }

    if(0 == EVP_VerifyUpdate(mdctx.get(), (void*)data, strlen(data)))
    {
        return -1;
    }
//!!!!!!!!!!!!!!!!!!!
    std::shared_ptr<BIO> b64 = std::shared_ptr<BIO>(BIO_new(BIO_f_base64()), BIO_free);
    BIO_set_flags(b64.get(),BIO_FLAGS_BASE64_NO_NL);

    std::shared_ptr<BIO> bPubKey = std::shared_ptr<BIO>(BIO_new(BIO_s_mem()), BIO_free);
    BIO_puts(bPubKey.get(),pub_key_id);
    BIO_push(b64.get(), bPubKey.get());

    std::shared_ptr<EVP_PKEY> pubkey = std::shared_ptr<EVP_PKEY>(d2i_PUBKEY_bio(b64.get(), NULL), EVP_PKEY_free);
//!!!!!!!!!!!!!!!!!!!
    std::string decoded_signature = Base64Decode(std::string(signature));
    return EVP_VerifyFinal(mdctx.get(), (unsigned char*)decoded_signature.c_str(), decoded_signature.length(), pubkey.get());
}

从'google inapp billing'给出的公钥初始化EVP_PKEY（在openssl中）

2 个答案: