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How to download files from FTPS in C#

Our IT department gave me credentials for an FTPS, which I can access using FileZilla
But I also need to access the FTPS using an application I am working on to automate the process. The information provided to me was,
That this is an FTP over TLS/SSL
IP: xxx.xxx.xx.xx
Port: 990 <-- suggesting its an implicit encryption
UserName: username.ftp
Password: password123
After reading some posts on WinSCP on stack and their documentation, I still can't access the ftps using my application. My code so far..
SessionOptions sessionOp = new SessionOptions()
{
FtpSecure = FtpSecure.Implicit,
Protocol = Protocol.Ftp,
HostName = IP,
UserName = userName,
Password = password,
};
sessionOp.AddRawSettings("ProxyMethod", "3");
sessionOp.AddRawSettings("ProxyPort", "990");
using (Session session = new Session())
{
session.Open(sessionOp);
var list = session.ListDirectory(dir);
Console.WriteLine(list);
}
The error I get is, "Failed to Connect" from WinSCP
How can I access this FTPS?

What you did is configuring the HTTP Proxy port to 990. Instead you should configure the FTPS port.
SessionOptions sessionOp = new SessionOptions()
{
FtpSecure = FtpSecure.Implicit,
Protocol = Protocol.Ftp,
HostName = IP,
UserName = userName,
Password = password,
PortNumber = 990
};
and remove the lines
sessionOp.AddRawSettings("ProxyMethod", "3");
sessionOp.AddRawSettings("ProxyPort", "990");
Also, I suggest using the WinSCP GUI to try this instead of FileZilla, considering that the library is related to the GUI.

Connecting to LDAP with PHP Successfully, but cannot connect with C#

I am connecting successfully to the LDAP with PHP, tried a whole lot of things but when I try with C# am always getting either "Server is not operational" or "The LDAP server in unavailable".
Here is the PHP code:
<?php
function login($username='user', $password='pass') {
if (empty($username) || empty($password)) {
throw new BadCredentialsException('Invalid username or password.');
}
if (($ldap = #ldap_connect($url = 'ldap://ds.xyz-example.com', $port = 636)) === false) {
echo('Error connecting LDAP server with url %s on port %d.');
}
if (!#ldap_bind($ldap, sprintf($dn='uid=%s,ou=People,dc=xyz-example,dc=com', $username), $password)) {
$error = ldap_errno($ldap);
if ($error === 0x31) {
echo('Invalid username or password.');
} else {
echo('error during authentication with LDAP.');
}
}
return true;
}
login(); // call the function
?>
This is working perfect but I need it with C#. How can I do this with C# using the port and the dn and the user and pass?
Here is what I tried with C# but with an error "Server is not operational"
string ldapPath = "LDAP://ds.xyz-example.com:636/UID=user,OU=People,DC=xyz-example,DC=com";
string user = "user";
string password = "pass";
DirectoryEntry deSSL = new DirectoryEntry(ldapPath, user, password, AuthenticationTypes.SecureSocketsLayer);
try
{
user = deSSL.Properties["uid"][0].ToString(); //if this works, we bound successfully
Response.Output.Write("Success... {0} has bound", user);
}
catch (Exception ex)
{
Response.Output.Write("Bind Failure: {0}", ex.Message);
}
Thanks in advance!

Could it be your library doesn't implement LDAP but rather a weird non-standard Microsoft version of LDAP called ActiveDirectory, which only works when the server is an actual ActiveDirectory Server and doesn't quite work as easily when you use non-microsoft servers, such as OpenLDAP?
Could it be?

AE.Net.Mail not able to connect to outlook.office365.com IMAP

I am finding that I am unable to connect to outlook.office365.com's IMAP server using AE.Net.Mail. The code is very simple:
this._imapClient = new ImapClient(imapServer, username, password, AE.Net.Mail.AuthMethods.Login, port, enableSSL)
I find that I can connect to GMail with no issues, but office365 outlook will not connect, I keep getting timeouts. I've verified the IMAP settings by putting them in to Outlook and in to Thunderbird.
Has anyone else had trouble connecting AE.Net.Mail to Office365's IMAP server?

AE.Net.Mail is quite buggy and has not seen any development in over a year last I checked. I would recommend using MailKit instead.
I just confirmed that MailKit works with Office365.com with the following code snippet:
using (var client = new ImapClient ()) {
client.Connect ("outlook.office365.com", 993, true);
client.Authenticate ("username", "password");
// get the unread messages
var uids = client.Inbox.Search (SearchQuery.NotSeen);
foreach (var uid in uids) {
var message = client.Inbox.GetMessage (uid);
}
client.Disconnect (true);
}
Hope that helps.

Found I am able to connect by increasing the timeouts:
_imapClient.ServerTimeout = 120000;
_imapClient.IdleTimeout = 120000;
_imapClient.Connect(_imapServer, _port, _enableSSL, false);
_imapClient.Login(_username, _password);
_imapClient.SelectMailbox("Inbox");

Retrieving all user accounts on an accessible external Active Directory server over LDAPS

I need to connect to an external LDAP server that is accessible to me but only over LDAPS.
The information I have available is username, server, password. I need to query and retrieve a list of all users. The format I have the details in are
Username: domain\username
Password: {password}
Domain: remote.{domain}.net.au
The following code I wrote will authenticate my user account successfully, but I now need to enumerate all users which is where I'm having issues. Ideally this would be ALL users in the directory, not from within a specific OU. Again, I don't have the fully qualified paths to any OUs for this server. The server has a self signed certificate which is why in my example I am specifically telling it to accept the certificate.
int port = secured ? 636 : 389;
LdapConnection connection = new LdapConnection(new LdapDirectoryIdentifier(ldapServer, port, false, false));
if (secured)
{
connection.SessionOptions.ProtocolVersion = 3;
connection.SessionOptions.SecureSocketLayer = true;
}
connection.Credential = new NetworkCredential(username, password);
connection.AuthType = AuthType.Basic;
connection.SessionOptions.VerifyServerCertificate += (conn, cert) => { return true; };
connection.Bind();
return connection;

So the answer is in Performing a Simple Search sample of Introduction to System.DirectoryServices.Protocols (S.DS.P) with :
// create a search filter to find all objects
string ldapSearchFilter = "(&(objectCategory=person)(objectClass=user))";

Using StartTLS with LDAP from System.DirectoryServices

I'm trying to connect to an LDAP server which requires StartTLS, but having no luck - whenever I use either the SessionOptions.StartTransportLayerSecurity(..) or set SessionOptions.SecureSocketLayer to true, I get exceptions.
Here's the code I'm using:
using (var connection = new LdapConnection(new LdapDirectoryIdentifier(config.LdapServer, config.Port, false, false)))
{
connection.SessionOptions.ProtocolVersion = 3;
connection.Credential = new NetworkCredential(config.BindDN, config.BindPassword);
connection.SessionOptions.VerifyServerCertificate += (conn, cert) => {return true;};
connection.AuthType = AuthType.Basic;
//connection.SessionOptions.SecureSocketLayer = true;
connection.SessionOptions.StartTransportLayerSecurity(null); // throws here, same if done after bind.
connection.Bind();
... do stuff with connection
}
The resulting exception is "TlsOperationException: An unspecified error occurred", which happens when invoking the StartTransportLayerSecurity method.
I've tested the code against both and OpenLDAP server and Active Directory, but neither works.
Does anyone know how to get StartTLS working with System.DirectoryServices?

There used to be a fair amount of subtle LDAP stack incompatibilities in the wild, which could still apply to the potentially legacy scenario your customer might be using.
The following are the most commonly encountered issues regarding incompatibilities between OpenLDAP and Microsoft's LDAP stack (I'll amend and/or replace these links once more info is available):
The OpenLDAP StartTLS issues (ITS#3037) (summarized in On getting OpenLDAP and Windows LDAP to interop) have triggered a respective hotfix:
You cannot send Start TLS requests from a computer that is running Windows Server 2003 or Windows XP or Windows Vista to a server that is running OpenLDAP Software
An extended operation that is sent to an LDAP server by API over the LDAP service causes a protocol error
Obviously, updating either OpenLDAP and/or Windows (ideally both of course) should remedy these issues, if they turn out to be the culprit here.
Good luck!

Please read this topic:
Binding over a TLS/SSL Encrypted Connection
Example 19. Binding to an ADAM instance on secure port 50001 using Basic authentication and SSL/TLS
string hostNameAndSSLPort = "sea-dc-02.fabrikam.com:50001";
string userName = "cn=User1,cn=AdamUsers,cn=ap1,dc=fabrikam,dc=com";
string password = "adamPassword01!";
// establish a connection
LdapConnection connection = new LdapConnection(hostNameAndSSLPort);
// create an LdapSessionOptions object to configure session
// settings on the connection.
LdapSessionOptions options = connection.SessionOptions;
options.ProtocolVersion = 3;
options.SecureSocketLayer = true;
connection.AuthType = AuthType.Basic;
NetworkCredential credential =
new NetworkCredential(userName, password);
connection.Credential = credential;
try
{
connection.Bind();
Console.WriteLine("\nUser account {0} validated using " +
"ssl.", userName);
if (options.SecureSocketLayer == true)
{
Console.WriteLine("SSL for encryption is enabled\nSSL information:\n" +
"\tcipher strength: {0}\n" +
"\texchange strength: {1}\n" +
"\tprotocol: {2}\n" +
"\thash strength: {3}\n" +
"\talgorithm: {4}\n",
options.SslInformation.CipherStrength,
options.SslInformation.ExchangeStrength,
options.SslInformation.Protocol,
options.SslInformation.HashStrength,
options.SslInformation.AlgorithmIdentifier);
}
}
catch (LdapException e)
{
Console.WriteLine("\nCredential validation for User " +
"account {0} using ssl failed\n" +
"LdapException: {1}", userName, e.Message);
}
catch (DirectoryOperationException e)
{
Console.WriteLine("\nCredential validation for User " +
"account {0} using ssl failed\n" +
"DirectoryOperationException: {1}", userName, e.Message);
}
And the next example show "How to use TLS to authenticate and perform a task"
string hostOrDomainName = "fabrikam.com";
string userName = "user1";
string password = "password1";
// establish a connection to the directory
LdapConnection connection = new LdapConnection(hostOrDomainName);
NetworkCredential credential =
new NetworkCredential(userName, password, domainName);
connection.Credential = credential;
connection.AuthType = AuthType.Basic;
LdapSessionOptions options = connection.SessionOptions;
options.ProtocolVersion = 3;
try
{
options.StartTransportLayerSecurity(null);
Console.WriteLine("TLS started.\n");
}
catch (Exception e)
{
Console.WriteLine("Start TLS failed with {0}",
e.Message);
return;
}
try
{
connection.Bind();
Console.WriteLine("Bind succeeded using basic " +
"authentication and SSL.\n");
Console.WriteLine("Complete another task over " +
"this SSL connection");
TestTask(hostName);
}
catch (LdapException e)
{
Console.WriteLine(e.Message);
}
try
{
options.StopTransportLayerSecurity();
Console.WriteLine("Stop TLS succeeded\n");
}
catch (Exception e)
{
Console.WriteLine("Stop TLS failed with {0}", e.Message);
}
Console.WriteLine("Switching to negotiate auth type");
connection.AuthType = AuthType.Negotiate;
Console.WriteLine("\nRe-binding to the directory");
connection.Bind();
// complete some action over this non-SSL connection
// note, because Negotiate was used, the bind request
// is secure.
// run a task using this new binding
TestTask(hostName);

After a bit more work on this issue I found that I was running up against a couple of issues:
There was a bug in the code where the port number was being incorrectly changed to the SSL port (636) when connecting to AD in our test suite (doh!).
The OpenLDAP test server (that was a replica of our customers) was using openldap-2.4.18 - which has known issues with StartTLS.
After applying a patch to OpenLDAP (as discussed here - http://www.openldap.org/lists/openldap-bugs/200405/msg00096.html) we were able to fix #2 - at which point we started getting a different error "A local error occurred".
Though originally we had this code:
connection.SessionOptions.VerifyServerCertificate
+= (conn, cert) => {return true;};
We had removed it while testing, and because the OpenLDAP server was using a self-signed cert, that was not in a trusted store. Re-introducing that callback resolved this issue, though we now make it a configurable option i.e. "Verify Server Certificate Y/N" so customers need to opt into skipping the check (mostly for our QA team to use).
Thanks Steffen for pointing me in the direction of OpenLDAP versions which lead me to this solution.