std::string HmacSha1Signer::generate()

in sdk/src/signer/HmacSha1Signer.cc [38:101]

• 55 lines of code
• 3 McCabe index (conditional complexity)

std::string HmacSha1Signer::generate(const std::string & src, const std::string & secret)
{
    if (src.empty())
        return std::string();

#if 0//def _WIN32
    typedef struct _my_blob {
        BLOBHEADER hdr;
        DWORD dwKeySize;
        BYTE rgbKeyData[];
    }my_blob;

    DWORD kbLen = sizeof(my_blob) + secret.size();
    my_blob * kb = (my_blob *)LocalAlloc(LPTR, kbLen);
    kb->hdr.bType = PLAINTEXTKEYBLOB;
    kb->hdr.bVersion = CUR_BLOB_VERSION;
    kb->hdr.reserved = 0;
    kb->hdr.aiKeyAlg = CALG_RC2;
    kb->dwKeySize = secret.size();
    memcpy(&kb->rgbKeyData, secret.c_str(), secret.size());

    HCRYPTPROV hProv = 0;
    HCRYPTKEY hKey = 0;
    HCRYPTHASH hHmacHash = 0;
    BYTE pbHash[32];
    DWORD dwDataLen = 32;
    HMAC_INFO HmacInfo;
    ZeroMemory(&HmacInfo, sizeof(HmacInfo));
    HmacInfo.HashAlgid = CALG_SHA1;

    CryptAcquireContext(&hProv, NULL, MS_ENHANCED_PROV, PROV_RSA_FULL, CRYPT_VERIFYCONTEXT | CRYPT_NEWKEYSET);
    CryptImportKey(hProv, (BYTE*)kb, kbLen, 0, CRYPT_IPSEC_HMAC_KEY, &hKey);
    CryptCreateHash(hProv, CALG_HMAC, hKey, 0, &hHmacHash);
    CryptSetHashParam(hHmacHash, HP_HMAC_INFO, (BYTE*)&HmacInfo, 0);
    CryptHashData(hHmacHash, (BYTE*)(src.c_str()), src.size(), 0);
    CryptGetHashParam(hHmacHash, HP_HASHVAL, pbHash, &dwDataLen, 0);

    LocalFree(kb);
    CryptDestroyHash(hHmacHash);
    CryptDestroyKey(hKey);
    CryptReleaseContext(hProv, 0);

    DWORD dlen = 0;
    CryptBinaryToString(pbHash, dwDataLen, CRYPT_STRING_BASE64 | CRYPT_STRING_NOCRLF, NULL, &dlen);
    char* dest = new char[dlen];
    CryptBinaryToString(pbHash, dwDataLen, CRYPT_STRING_BASE64 | CRYPT_STRING_NOCRLF, dest, &dlen);

    std::string ret = std::string(dest, dlen);
    delete[] dest;
    return ret;
#else
    unsigned char md[32];
    unsigned int mdLen = 32;

    if (HMAC(EVP_sha1(), secret.c_str(), static_cast<int>(secret.size()),
        reinterpret_cast<const unsigned char*>(src.c_str()), src.size(),
        md, &mdLen) == nullptr)
        return std::string();

    char encodedData[100];
    EVP_EncodeBlock(reinterpret_cast<unsigned char*>(encodedData), md, mdLen);
    return encodedData;
#endif
}