FTP Library Features | ComponentPro | ComponentPro

static void Main()
{
    // Create a new class instance.
    Ftp client = new Ftp();

    client.CertificateReceived += client_CertificateReceived;

    // Connect to the FTP server.
    client.Connect("myserver", 21, SslSecurityMode.Explicit);

    // Authenticate.
    client.Authenticate("userName", "password");

    // Do something here...
    client.DownloadFile("/my remote file.dat", "my local file");

    // Disconnect.
    client.Disconnect();
}

/// <summary>
/// Returns all issues of the given certificate.
/// </summary>
/// <param name="status">The certificate verification result.</param>
/// <param name="code">The error code.</param>
/// <returns>Certificate problems.</returns>
private static string GetCertProblem(CertificateVerificationStatus status, int code)
{
    switch (status)
    {
        case CertificateVerificationStatus.TimeNotValid:
            return "Server's certificate has expired or is not valid yet.";

        case CertificateVerificationStatus.Revoked:
            return "Server's certificate has been revoked.";

        case CertificateVerificationStatus.UnknownCa:
            return "Server's certificate was issued by an unknown authority.";

        case CertificateVerificationStatus.UntrustedRoot:
            return "Server's certificate was issued by an untrusted authority.";

        case CertificateVerificationStatus.IncompleteChain:
            return "Server's certificate does not chain up to a trusted root authority.";

        case CertificateVerificationStatus.Malformed:
            return "Server's certificate is malformed.";

        case CertificateVerificationStatus.CnNotMatch:
            return "Server hostname does not match the certificate.";

        case CertificateVerificationStatus.UnknownError:
            return string.Format("Error {0:x} encountered while validating server's certificate.", code);

        default:
            return status.ToString();
    }
}

static void client_CertificateReceived(object sender, ComponentPro.Security.CertificateReceivedEventArgs e)
{
    X509Certificate2 cert = e.ServerCertificates[0];

    CertificateVerificationStatus status = e.Status;

    CertificateVerificationStatus[] values = (CertificateVerificationStatus[])Enum.GetValues(typeof(CertificateVerificationStatus));

    StringBuilder sbIssues = new StringBuilder();
    for (int i = 0; i < values.Length; i++)
    {
        // Matches the validation status?
        if ((status & values[i]) == 0)
            continue;

        // The issue is processed.
        status ^= values[i];

        sbIssues.AppendFormat("{0}\r\n", GetCertProblem(values[i], e.ErrorCode));
    }

    Console.WriteLine("Issue: " + sbIssues.ToString());

    Console.WriteLine("Subject: " + cert.SubjectName.Name);
    Console.WriteLine("Issuer: " + cert.IssuerName.Name);
    Console.WriteLine("Effective Date: " + cert.NotBefore);
    Console.WriteLine("Expiry Date: " + cert.NotAfter);
    Console.ResetColor();
    Console.Write("Do you want to accept this certificate (Add to trusted list, Yes, No) [a,y,n]?");

    string response = Console.ReadLine().Trim().ToLower();

    // Add certiticate of the issuer CA to the trusted list.
    if (response == "a")
    {
        e.AddToTrustedRoot = true;
    }
    else if (response == "y")
    {
        e.Accept = true;
    }
}
Shared Sub Main()
    ' Create a new class instance.
    Dim client As New Ftp()

    AddHandler client.CertificateReceived, AddressOf client_CertificateReceived

    ' Connect to the FTP server.
    client.Connect("myserver", 21, SslSecurityMode.Explicit)

    ' Authenticate.
    client.Authenticate("userName", "password")

    ' Do something here...
    client.DownloadFile("/my remote file.dat", "my local file")

    ' Disconnect.
    client.Disconnect()
End Sub

''' <summary>
''' Returns all issues of the given certificate.
''' </summary>
''' <param name="status">The certificate verification result.</param>
''' <param name="code">The error code.</param>
''' <returns>Certificate problems.</returns>
Private Shared Function GetCertProblem(ByVal status As CertificateVerificationStatus, ByVal code As Integer) As String
    Select Case status
        Case CertificateVerificationStatus.TimeNotValid
            Return "Server's certificate has expired or is not valid yet."

        Case CertificateVerificationStatus.Revoked
            Return "Server's certificate has been revoked."

        Case CertificateVerificationStatus.UnknownCa
            Return "Server's certificate was issued by an unknown authority."

        Case CertificateVerificationStatus.UntrustedRoot
            Return "Server's certificate was issued by an untrusted authority."

        Case CertificateVerificationStatus.IncompleteChain
            Return "Server's certificate does not chain up to a trusted root authority."

        Case CertificateVerificationStatus.Malformed
            Return "Server's certificate is malformed."

        Case CertificateVerificationStatus.CnNotMatch
            Return "Server hostname does not match the certificate."

        Case CertificateVerificationStatus.UnknownError
            Return String.Format("Error {0:x} encountered while validating server's certificate.", code)

        Case Else
            Return status.ToString()
    End Select
End Function

Private Shared Sub client_CertificateReceived(ByVal sender As Object, ByVal e As ComponentPro.Security.CertificateReceivedEventArgs)
    Dim cert As X509Certificate2 = e.ServerCertificates(0)

    Dim status As CertificateVerificationStatus = e.Status

    Dim values() As CertificateVerificationStatus = CType(System.Enum.GetValues(GetType(CertificateVerificationStatus)), CertificateVerificationStatus())

    Dim sbIssues As New StringBuilder()
    For i As Integer = 0 To values.Length - 1
        ' Matches the validation status?
        If (status And values(i)) = 0 Then
            Continue For
        End If

        ' The issue is processed.
        status = status Xor values(i)

        sbIssues.AppendFormat("{0}" & vbCrLf, GetCertProblem(values(i), e.ErrorCode))
    Next i

    Console.WriteLine("Issue: " & sbIssues.ToString())

    Console.WriteLine("Subject: " & cert.SubjectName.Name)
    Console.WriteLine("Issuer: " & cert.IssuerName.Name)
    Console.WriteLine("Effective Date: " & cert.NotBefore)
    Console.WriteLine("Expiry Date: " & cert.NotAfter)
    Console.ResetColor()
    Console.Write("Do you want to accept this certificate (Add to trusted list, Yes, No) [a,y,n]?")

    Dim response As String = Console.ReadLine().Trim().ToLower()

    ' Add certiticate of the issuer CA to the trusted list.
    If response = "a" Then
        e.AddToTrustedRoot = True
    ElseIf response = "y" Then
        e.Accept = True
    End If
End Sub