使用Activex主要为了嵌入网页和服务端C#来调用加密。这里只给出关键代码吧

1.私钥解密

STDMETHODIMP CMAddr::DePrivKey(BSTR encode, BSTR* orign)
{

    //HCERTSTORE  hCertStore = NULL;
    BOOL ret=TRUE;
    HCRYPTPROV_OR_NCRYPT_KEY_HANDLE hCryptProv =NULL;
    BOOL bFreeKeyProv=FALSE;
    DWORD dwKeyType;
    HCRYPTKEY hKey = NULL;
    BYTE* pTempByte=NULL;
    CString outStr;
    CString run;

    run="DecodeJson";
    CString b64Str(encode);
    CString tempStr;
    CStringDecodeBase64(b64Str,tempStr);
    Json::Reader reader;
    Json::Value root;  

    if(NULL==Current_PCTX)
    {
        MessageBox("请选择证书！");
        goto cleanup;
    }

    if (!reader.parse(tempStr.GetBuffer(), root))
    {
        goto cleanup;
    }

    DWORD dwCount=root.size();
    pTempByte=new BYTE[dwCount];
    for(DWORD i=0;i<dwCount;i++)
    {
        pTempByte[i]=root[i].asInt();
    }
    
    run="CryptAcquireCertificatePrivateKey";
    ret=CryptAcquireCertificatePrivateKey(Current_PCTX, 0, 0, &hCryptProv, &dwKeyType, &bFreeKeyProv);
    if(!ret)goto cleanup;

    run="CryptGetUserKey";
    ret=CryptGetUserKey(hCryptProv,AT_KEYEXCHANGE,&hKey);
    if(!ret)goto cleanup;

    run="CryptDecrypt";
    ret=CryptDecrypt(hKey, 0, true, 0,pTempByte, &dwCount);
    if(!ret)goto cleanup;

    for(DWORD i=0;i<dwCount;i++)
    {
        outStr.AppendChar(pTempByte[i]);
    }

cleanup:
    if(NULL!=pTempByte)
    {
        delete[] pTempByte;
        pTempByte=NULL;
    }

    if(NULL!=hKey)
    {
        CryptDestroyKey(hKey);
    }

    if(NULL!=hCryptProv&&bFreeKeyProv)
    {
        CryptReleaseContext(hCryptProv,0);
    }

    if(!ret)
    {
        outStr.Empty();
        outStr.Format("ErrorCode:%0x"+run, GetLastError());
    }
    CComBSTR tempSTR(outStr);
    tempSTR.CopyTo(orign);
    tempSTR.Empty();
    return S_OK;
}

2.公钥加密

STDMETHODIMP CMAddr::EnPubKey(BSTR orign, BSTR cert, BSTR* encode)
{
    PCCERT_CONTEXT pCertContext=NULL;
    HCERTSTORE hCertStore = NULL;    
    HCRYPTPROV hCryptProv = NULL;
    HCRYPTKEY hPubKey = NULL;
    BYTE* pBinByte=NULL;
    BYTE* pOrignByte=NULL;

    BOOL ret;
    DWORD binBytes = 0;
    CString outStr;
    CString run;
    CString tempStr;
    Json::Value value;

    //get cert
    std::wstring scert(cert,SysStringLen(cert));

    run="Acquire Context";
    ret=CryptAcquireContext(&hCryptProv,NULL, NULL,PROV_RSA_FULL,0);
    if(!ret)goto cleanup;

    run="Read Cert";
    ret=CryptStringToBinaryW(scert.c_str()  , scert.length() ,CRYPT_STRING_BASE64HEADER , NULL , &binBytes ,NULL,NULL);
    if(!ret)goto cleanup;

    pBinByte=new BYTE[binBytes];
    ZeroMemory(pBinByte,binBytes);
    ret=CryptStringToBinaryW(scert.c_str() , scert.length() ,CRYPT_STRING_BASE64HEADER , pBinByte, &binBytes ,NULL,NULL);
    if(!ret)goto cleanup;

    run="Create Cert";
    pCertContext = CertCreateCertificateContext( PKCS_7_ASN_ENCODING | X509_ASN_ENCODING, pBinByte , binBytes );

    run="Import PubKey";
    ret=CryptImportPublicKeyInfo(hCryptProv,PKCS_7_ASN_ENCODING | X509_ASN_ENCODING,
        &(pCertContext->pCertInfo->SubjectPublicKeyInfo),
        &hPubKey);
    if(!ret)goto cleanup;

    DWORD orignLen=SysStringLen(orign);
    DWORD pDataLen=orignLen;


    run="Run Encrypt";
    ret=CryptEncrypt(hPubKey,NULL,true,0,NULL,&pDataLen,orignLen);
    if(!ret)goto cleanup;

    pOrignByte=new BYTE[pDataLen];
    ZeroMemory(pOrignByte,pDataLen);

    for(DWORD i=0;i<orignLen;i++)
    {
        pOrignByte[i]=(BYTE)orign[i];
    }

    ret=CryptEncrypt(hPubKey,NULL,true,0,pOrignByte,&orignLen,pDataLen);
    if(!ret)goto cleanup;

    for(DWORD i=0;i<pDataLen;i++)
    {
        value[i]=pOrignByte[i];
    }
    tempStr=value.toStyledString().c_str();
    CStringEncodeBase64(tempStr,outStr);

cleanup:
    if(NULL!=pOrignByte)
    {
        delete[] pOrignByte;
        pOrignByte=NULL;
    }

    if(NULL!=pBinByte)
    {
        delete[] pBinByte;
        pBinByte=NULL;
    }

    if(NULL!=pCertContext)
    {
        CertFreeCertificateContext(pCertContext);
    }

    if(NULL!=hPubKey)
    {
        CryptDestroyKey(hPubKey);
    }


    if(NULL!=hCryptProv)
    {
        CryptReleaseContext(hCryptProv,0);
    }

    if(!ret)
    {
        outStr.Empty();
        outStr.Format(run+"ErrorCode:%0x", GetLastError());
    }


    CComBSTR outStrTemp(outStr);
    outStrTemp.CopyTo(encode);
    outStrTemp.Empty();
    return S_OK;
}