public bool IsValidMXRecord(string _domain)
{
try
{
Dns_Client.DnsServers = new string[] { "8.8.8.8" };
Dns_Client.UseDnsCache = true;
using (Dns_Client dns = new Dns_Client())
{
DnsServerResponse reponse = null;
reponse = dns.Query(_domain, LumiSoft.Net.DNS.DNS_QType.MX);
if (((LumiSoft.Net.DNS.DNS_rr_MX)reponse.Answers[0]).Host != null)
{
return(true);
}
else
{
return(false);
}
}
}
catch (Exception ex)
{
return(false);
}
}
/// <summary>
/// Gets host name. If fails returns ip address.
/// </summary>
/// <param name="ip">IP address which to reverse lookup.</param>
/// <returns>Returns host name of specified IP address.</returns>
/// <exception cref="ArgumentNullException">Is raised when <b>ip</b> is null.</exception>
public static string GetHostName(IPAddress ip)
{
if (ip == null)
{
throw new ArgumentNullException("ip");
}
string retVal = ip.ToString();
try
{
Dns_Client dns = new Dns_Client();
DnsServerResponse response = dns.Query(ip.ToString(), QTYPE.PTR);
if (response.ResponseCode == RCODE.NO_ERROR)
{
DNS_rr_PTR[] ptrs = response.GetPTRRecords();
if (ptrs.Length > 0)
{
retVal = ptrs[0].DomainName;
}
}
}
catch {}
return retVal;
}
/// <summary>
/// Connects to sepcified host.
/// </summary>
/// <param name="localEndpoint">Sets local endpoint. Pass null, to use default.</param>
/// <param name="host">Host name or IP address.</param>
/// <param name="port">Port where to connect.</param>
/// <param name="ssl">Specifies if to connected via SSL. Default SMTP port is 25 and SSL port is 465.</param>
public void Connect(IPEndPoint localEndpoint, string host, int port, bool ssl)
{
m_pSocket = new SocketEx();
if (localEndpoint != null)
{
m_pSocket.Bind(localEndpoint);
}
// Create logger
if (SessionLog != null)
{
m_pLogger = new SocketLogger(m_pSocket.RawSocket, SessionLog);
m_pLogger.SessionID = Guid.NewGuid().ToString();
m_pSocket.Logger = m_pLogger;
}
if (host.IndexOf("@") == -1)
{
m_pSocket.Connect(host, port, ssl);
}
else
{
//---- Parse e-domain -------------------------------//
string domain = host;
// eg. Ivx <*****@*****.**>
if (domain.IndexOf("<") > -1 && domain.IndexOf(">") > -1)
{
domain = domain.Substring(domain.IndexOf("<") + 1,
domain.IndexOf(">") - domain.IndexOf("<") - 1);
}
if (domain.IndexOf("@") > -1)
{
domain = domain.Substring(domain.LastIndexOf("@") + 1);
}
if (domain.Trim().Length == 0)
{
if (m_pLogger != null)
{
m_pLogger.AddTextEntry("Destination address '" + host + "' is invalid, aborting !");
}
throw new Exception("Destination address '" + host + "' is invalid, aborting !");
}
//--- Get MX record -------------------------------------------//
Dns_Client dns = new Dns_Client();
Dns_Client.DnsServers = m_pDnsServers;
DnsServerResponse dnsResponse = dns.Query(domain, QTYPE.MX);
bool connected = false;
switch (dnsResponse.ResponseCode)
{
case RCODE.NO_ERROR:
DNS_rr_MX[] mxRecords = dnsResponse.GetMXRecords();
// Try all available hosts by MX preference order, if can't connect specified host.
foreach (DNS_rr_MX mx in mxRecords)
{
try
{
if (m_pLogger != null)
{
m_pLogger.AddTextEntry("Connecting with mx record to: " + mx.Host);
}
m_pSocket.Connect(mx.Host, port, ssl);
connected = true;
break;
}
catch (Exception x)
{
// Just skip and let for to try next host.
if (m_pLogger != null)
{
m_pLogger.AddTextEntry("Failed connect to: " + mx.Host + " error:" +
x.Message);
}
}
}
// None of MX didn't connect
if (mxRecords.Length > 0 && !connected)
{
throw new Exception("Destination email server is down");
}
/* Rfc 2821 5
If no MX records are found, but an A RR is found, the A RR is treated as
if it was associated with an implicit MX RR, with a preference of 0,
pointing to that host.
*/
if (!connected)
{
// Try to connect with A record
IPAddress[] ipEntry = null;
try
{
if (m_pLogger != null)
{
m_pLogger.AddTextEntry("No mx record, trying to get A record for: " +
domain);
}
ipEntry = Dns_Client.Resolve(domain);
}
catch
{
if (m_pLogger != null)
{
m_pLogger.AddTextEntry("Invalid domain,no MX or A record: " + domain);
}
throw new Exception("Invalid domain,no MX or A record: " + domain);
}
try
{
if (m_pLogger != null)
{
m_pLogger.AddTextEntry("Connecting with A record to:" + domain);
}
m_pSocket.Connect(domain, port, ssl);
}
catch
{
if (m_pLogger != null)
{
m_pLogger.AddTextEntry("Failed connect to:" + domain);
}
throw new Exception("Destination email server is down");
}
}
break;
case RCODE.NAME_ERROR:
if (m_pLogger != null)
{
m_pLogger.AddTextEntry("Invalid domain,no MX or A record: " + domain);
}
throw new Exception("Invalid domain,no MX or A record: " + domain);
case RCODE.SERVER_FAILURE:
if (m_pLogger != null)
{
m_pLogger.AddTextEntry("Dns server unvailable.");
}
throw new Exception("Dns server unvailable.");
}
}
/*
* Notes: Greeting may be single or multiline response.
*
* Examples:
* 220<SP>SMTP server ready<CRLF>
*
* 220-SMTP server ready<CRLF>
* 220-Addtitional text<CRLF>
* 220<SP>final row<CRLF>
*
*/
// Read server response
string responseLine = m_pSocket.ReadLine(1000);
while (!responseLine.StartsWith("220 "))
{
// If lisne won't start with 220, then its error response
if (!responseLine.StartsWith("220"))
{
throw new Exception(responseLine);
}
responseLine = m_pSocket.ReadLine(1000);
}
m_Connected = true;
}
/// <summary>
/// Gets specified email domain possible connect points. Values are in priority descending order.
/// </summary>
/// <param name="domain">Email address or domain name.</param>
/// <returns>Returns possible email server connection points.</returns>
public IPAddress[] GetDestinations(string domain)
{
/*
1) Add MX records
2) Add A records
*/
// We have email address, just get domain from it.
if (domain.IndexOf('@') > -1)
{
domain = domain.Substring(domain.IndexOf('@') + 1);
}
List<IPAddress> retVal = new List<IPAddress>();
Dns_Client dns = new Dns_Client();
Dns_Client.DnsServers = DnsServers;
DnsServerResponse response = dns.Query(domain, QTYPE.MX);
// Add MX
foreach (DNS_rr_MX mx in response.GetMXRecords())
{
try
{
IPAddress[] ips = Dns.GetHostAddresses(mx.Host);
foreach (IPAddress ip in ips)
{
if (!retVal.Contains(ip))
{
retVal.Add(ip);
}
}
}
catch
{
// Probably wrong MX record, no A reocrd for it, so we don't get IP. Just skip it.
}
}
// Add A records only if no MX records.
if (retVal.Count == 0)
{
response = dns.Query(domain, QTYPE.A);
foreach (DNS_rr_A a in response.GetARecords())
{
IPAddress ip = a.IP;
if (!retVal.Contains(ip))
{
retVal.Add(ip);
}
}
}
return retVal.ToArray();
}
/// <summary>
/// Gets specified email domain SMTP hosts. Values are in descending priority order.
/// </summary>
/// <param name="domain">Domain name. This value can be email address too, then domain parsed automatically.</param>
/// <returns>Returns specified email domain SMTP hosts.</returns>
/// <exception cref="ArgumentNullException">Is raised when <b>domain</b> is null.</exception>
/// <exception cref="ArgumentException">Is raised when any of the arguments has invalid value.</exception>
/// <exception cref="DNS_ClientException">Is raised when DNS query failure.</exception>
public static string[] GetDomainHosts(string domain)
{
if (domain == null)
{
throw new ArgumentNullException("domain");
}
if (string.IsNullOrEmpty(domain))
{
throw new ArgumentException(
"Invalid argument 'domain' value, you need to specify domain value.");
}
// We have email address, parse domain.
if (domain.IndexOf("@") > -1)
{
domain = domain.Substring(domain.IndexOf('@') + 1);
}
List<string> retVal = new List<string>();
// Get MX records.
Dns_Client dns = new Dns_Client();
DnsServerResponse response = dns.Query(domain, QTYPE.MX);
if (response.ResponseCode == RCODE.NO_ERROR)
{
foreach (DNS_rr_MX mx in response.GetMXRecords())
{
// Block invalid MX records.
if (!string.IsNullOrEmpty(mx.Host))
{
retVal.Add(mx.Host);
}
}
}
else
{
throw new DNS_ClientException(response.ResponseCode);
}
/* RFC 2821 5.
If no MX records are found, but an A RR is found, the A RR is treated as if it
was associated with an implicit MX RR, with a preference of 0, pointing to that host.
*/
if (retVal.Count == 0)
{
retVal.Add(domain);
}
return retVal.ToArray();
}
//---- SMTP implementation ----//
#region function SendMessageToServer
private bool SendMessageToServer(string[] to, string reverse_path, Stream message)
{
// Get email from to string
for (int i = 0; i < to.Length; i++)
{
to[i] = (new InfoControl.Net.Mail.Mime.eAddress(to[i])).Email;
}
ArrayList defectiveEmails = new ArrayList();
Socket so = new Socket(AddressFamily.InterNetwork, SocketType.Stream, ProtocolType.Tcp);
so.SetSocketOption(SocketOptionLevel.Socket, SocketOptionName.SendTimeout, 15000);
BufferedSocket socket = new BufferedSocket(so);
SocketLogger logger = null;
if (m_LogCmds && this.SessionLog != null)
{
logger = new SocketLogger(so, this.SessionLog);
logger.SessionID = socket.GetHashCode().ToString();
socket.Logger = logger;
}
try{
string reply = "";
bool supports_SIZE = false;
bool supports_8BIT = false;
bool supports_BDAT = false;
if (m_UseSmartHost)
{
socket.Connect(new IPEndPoint(System.Net.Dns.Resolve(m_SmartHost).AddressList[0], m_Port));
}
else
{
//---- Parse e-domain -------------------------------//
string domain = to[0];
// eg. Ivx <*****@*****.**>
if (domain.IndexOf("<") > -1 && domain.IndexOf(">") > -1)
{
domain = domain.Substring(domain.IndexOf("<") + 1, domain.IndexOf(">") - domain.IndexOf("<") - 1);
}
if (domain.IndexOf("@") > -1)
{
domain = domain.Substring(domain.LastIndexOf("@") + 1);
}
if (domain.Trim().Length == 0)
{
if (logger != null)
{
logger.AddTextEntry("Destination address '" + to[0] + "' is invalid, aborting !");
}
return(false);
}
//--- Get MX record -------------------------------------------//
Dns_Client dns = new Dns_Client();
Dns_Client.DnsServers = m_DnsServers;
DnsServerResponse dnsResponse = dns.Query(domain, QTYPE.MX);
switch (dnsResponse.ResponseCode)
{
case RCODE.NO_ERROR:
MX_Record[] mxRecords = dnsResponse.GetMXRecords();
// Try all available hosts by MX preference order, if can't connect specified host.
foreach (MX_Record mx in mxRecords)
{
try{
if (logger != null)
{
logger.AddTextEntry("Connecting with mx record to: " + mx.Host);
}
socket.Connect(new IPEndPoint(System.Net.Dns.Resolve(mx.Host).AddressList[0], m_Port));
break;
}
catch { // Just skip and let for to try next host.
if (logger != null)
{
logger.AddTextEntry("Failed connect to: " + mx.Host);
}
}
}
/* Rfc 2821 5
* If no MX records are found, but an A RR is found, the A RR is treated as
* if it was associated with an implicit MX RR, with a preference of 0,
* pointing to that host.
*
*/
if (mxRecords.Length == 0)
{
// Try to connect with A record
IPHostEntry ipEntry = null;
try{
if (logger != null)
{
logger.AddTextEntry("No mx record, trying to get A record for: " + domain);
}
ipEntry = System.Net.Dns.Resolve(domain);
}
catch {
if (logger != null)
{
logger.AddTextEntry("Invalid domain,no MX or A record: " + domain);
}
OnError(SMTP_ErrorType.InvalidEmailAddress, to, "email domain <" + domain + "> is invalid");
defectiveEmails.AddRange(to);
if (logger != null)
{
logger.Flush();
}
return(false);
}
try{
if (logger != null)
{
logger.AddTextEntry("Connecting with A record to:" + domain);
}
socket.Connect(new IPEndPoint(ipEntry.AddressList[0], m_Port));
}
catch {
if (logger != null)
{
logger.AddTextEntry("Failed connect to:" + domain);
}
}
}
break;
case RCODE.NAME_ERROR:
if (logger != null)
{
logger.AddTextEntry("Invalid domain,no MX or A record: " + domain);
}
OnError(SMTP_ErrorType.InvalidEmailAddress, to, "email domain <" + domain + "> is invalid");
defectiveEmails.AddRange(to);
if (logger != null)
{
logger.Flush();
}
return(false);
case RCODE.SERVER_FAILURE:
if (logger != null)
{
logger.AddTextEntry("Dns server unvailable.");
}
OnError(SMTP_ErrorType.UnKnown, to, "Dns server unvailable.");
defectiveEmails.AddRange(to);
if (logger != null)
{
logger.Flush();
}
return(false);
}
}
if (!socket.Connected)
{
OnError(SMTP_ErrorType.UnKnown, to, "Unable connect to server !");
if (logger != null)
{
logger.Flush();
}
return(false);
}
#region Get 220 reply from server
/* NOTE: reply may be multiline
* 220 xx ready
* or
* 220-someBull
* 200 xx
*/
// Server must reply 220 - Server OK
reply = socket.ReadLine();
if (!IsReplyCode("220", reply))
{
OnError(SMTP_ErrorType.UnKnown, to, reply);
socket.SendLine("QUIT");
if (logger != null)
{
logger.Flush();
}
return(false);
}
else
{
// 220-xxx<CRLF>
// 220 aa<CRLF> - means end
// reply isn't complete, get more
while (reply.IndexOf("220 ") == -1)
{
reply += socket.ReadLine();
}
}
#endregion
#region cmd EHLO/HELO
// Send greeting to server
socket.SendLine("EHLO " + m_HostName);
reply = socket.ReadLine();
if (!IsReplyCode("250", reply))
{
// EHLO failed, mayby server doesn't support it, try HELO
socket.SendLine("HELO " + m_HostName);
reply = socket.ReadLine();
if (!IsReplyCode("250", reply))
{
OnError(SMTP_ErrorType.UnKnown, to, reply);
socket.SendLine("QUIT");
defectiveEmails.AddRange(to);
if (logger != null)
{
logger.Flush();
}
return(false);
}
// else{
// supports_ESMTP = false;
// }
}
else
{
// 250-xxx<CRLF>
// 250 aa<CRLF> - means end
// reply isn't complete, get more
while (reply.IndexOf("250 ") == -1)
{
reply += socket.ReadLine();
}
// Check if SIZE argument is supported
if (reply.ToUpper().IndexOf("SIZE") > -1)
{
supports_SIZE = true;
}
// Check if 8BITMIME argument is supported
if (reply.ToUpper().IndexOf("8BITMIME") > -1)
{
supports_8BIT = true;
}
// Check if CHUNKING argument is supported
if (reply.ToUpper().IndexOf("CHUNKING") > -1)
{
supports_BDAT = true;
}
}
#endregion
//*** All server today support 8-bit, just skip it.
// If server doesn't support 8bit mime, check if message is 8bit.
// If is we MAY NOT send this message or loss of data
/* if(!supports_8BIT){
* if(Is8BitMime(message)){
* OnError(SMTP_ErrorType.NotSupported,to,"Message is 8-Bit mime and server doesn't support it.");
* socket.SendLine("QUIT");
*
* if(logger != null){
* logger.Flush();
* }
* return false;
* }
* }*/
#region cmd AUTH
if (this.m_Username != null && m_Username.Length > 0 && m_Password != null && m_Password.Length > 0)
{
if (reply.ToUpper().IndexOf("AUTH") > -1)
{
if (reply.ToUpper().IndexOf("LOGIN") > -1)
{
socket.SendLine("AUTH LOGIN");
reply = socket.ReadLine();
if (!IsReplyCode("334", reply))
{
OnError(SMTP_ErrorType.NotAuthenticated, to, "Failed to authenticate");
socket.SendLine("QUIT");
if (logger != null)
{
logger.Flush();
}
return(false);
}
socket.SendLine(Convert.ToBase64String(System.Text.Encoding.ASCII.GetBytes(m_Username.ToCharArray())));
reply = socket.ReadLine();
if (!IsReplyCode("334", reply))
{
OnError(SMTP_ErrorType.NotAuthenticated, to, "Failed to authenticate");
socket.SendLine("QUIT");
if (logger != null)
{
logger.Flush();
}
return(false);
}
socket.SendLine(Convert.ToBase64String(System.Text.Encoding.ASCII.GetBytes(m_Password.ToCharArray())));
reply = socket.ReadLine();
if (!IsReplyCode("235", reply))
{
OnError(SMTP_ErrorType.NotAuthenticated, to, "Failed to authenticate");
socket.SendLine("QUIT");
if (logger != null)
{
logger.Flush();
}
return(false);
}
}
// if(reply.ToUpper().IndexOf("CRAM-MD5") > -1)
// {
// socket.SendLine("AUTH CRAM-MD5");
// reply = socket.ReadLine();
// if (IsReplyCode("334",auth))
// {
// socket.SendLine(Convert.ToBase64String(Encoding.ASCII.GetBytes(m_Username.ToCharArray())));
// socket.SendLine(Convert.ToBase64String(Encoding.ASCII.GetBytes(m_Password.ToCharArray())));
// }
// }
}
else
{
//server did not support AUTH
}
}
#endregion
#region cmd MAIL
// NOTE: Syntax:{MAIL FROM:<*****@*****.**> [SIZE=msgSize]<CRLF>}
// Send Mail From
if (supports_SIZE)
{
socket.SendLine("MAIL FROM:<" + reverse_path + "> SIZE=" + (message.Length - message.Position));
}
else
{
socket.SendLine("MAIL FROM:<" + reverse_path + ">");
}
reply = socket.ReadLine();
if (!IsReplyCode("250", reply))
{
// To Do: Check if size exceeded error:
OnError(SMTP_ErrorType.UnKnown, to, reply);
socket.SendLine("QUIT");
defectiveEmails.AddRange(to);
if (logger != null)
{
logger.Flush();
}
return(false);
}
#endregion
#region cmd RCPT
// NOTE: Syntax:{RCPT TO:<*****@*****.**><CRLF>}
bool isAnyValidEmail = false;
foreach (string rcpt in to)
{
// Send Mail To
socket.SendLine("RCPT TO:<" + rcpt + ">");
reply = socket.ReadLine();
if (!IsReplyCode("250", reply))
{
// Is unknown user
if (IsReplyCode("550", reply))
{
OnError(SMTP_ErrorType.InvalidEmailAddress, new string[] { rcpt }, reply);
}
else
{
OnError(SMTP_ErrorType.UnKnown, new string[] { rcpt }, reply);
}
defectiveEmails.Add(rcpt);
}
else
{
isAnyValidEmail = true;
}
}
// If there isn't any valid email - quit.
if (!isAnyValidEmail)
{
socket.SendLine("QUIT");
if (logger != null)
{
logger.Flush();
}
return(false);
}
//---------------------------------------------//
#endregion
#region cmd DATA
if (!(supports_BDAT && m_UseBDAT))
{
// Notify Data Start
socket.SendLine("DATA");
reply = socket.ReadLine();
if (!IsReplyCode("354", reply))
{
OnError(SMTP_ErrorType.UnKnown, to, reply);
socket.SendLine("QUIT");
defectiveEmails.AddRange(to);
if (logger != null)
{
logger.Flush();
}
return(false);
}
//------- Do period handling -----------------------------------------//
// If line starts with '.', add additional '.'.(Read rfc for more info)
MemoryStream msgStrmPeriodOk = Core.DoPeriodHandling(message, true, false);
//--------------------------------------------------------------------//
// Check if message ends with <CRLF>, if not add it. -------//
if (msgStrmPeriodOk.Length >= 2)
{
byte[] byteEnd = new byte[2];
msgStrmPeriodOk.Position = msgStrmPeriodOk.Length - 2;
msgStrmPeriodOk.Read(byteEnd, 0, 2);
if (byteEnd[0] != (byte)'\r' && byteEnd[1] != (byte)'\n')
{
msgStrmPeriodOk.Write(new byte[] { (byte)'\r', (byte)'\n' }, 0, 2);
}
}
msgStrmPeriodOk.Position = 0;
//-----------------------------------------------------------//
//---- Send message --------------------------------------------//
long totalSent = 0;
long totalLength = msgStrmPeriodOk.Length;
while (totalSent < totalLength)
{
byte[] dataBuf = new byte[4000];
int nCount = msgStrmPeriodOk.Read(dataBuf, 0, dataBuf.Length);
int countSended = socket.Send(dataBuf, 0, nCount, SocketFlags.None);
totalSent += countSended;
if (countSended != nCount)
{
msgStrmPeriodOk.Position = totalSent;
}
OnPartOfMessageIsSent(countSended, totalSent, totalLength);
}
//-------------------------------------------------------------//
msgStrmPeriodOk.Close();
// Notify End of Data
socket.SendLine(".");
reply = socket.ReadLine();
if (!IsReplyCode("250", reply))
{
OnError(SMTP_ErrorType.UnKnown, to, reply);
socket.SendLine("QUIT");
defectiveEmails.AddRange(to);
if (logger != null)
{
logger.Flush();
}
return(false);
}
}
#endregion
#region cmd BDAT
if (supports_BDAT && m_UseBDAT)
{
socket.SendLine("BDAT " + (message.Length - message.Position) + " LAST");
//---- Send message --------------------------------------------//
long totalSent = 0;
long totalLength = message.Length - message.Position;
while (totalSent < totalLength)
{
byte[] dataBuf = new byte[4000];
int nCount = message.Read(dataBuf, 0, dataBuf.Length);
int countSended = socket.Send(dataBuf, 0, nCount, SocketFlags.None);
totalSent += countSended;
if (countSended != nCount)
{
message.Position = totalSent;
}
OnPartOfMessageIsSent(countSended, totalSent, totalLength);
}
//-------------------------------------------------------------//
// Get store result
reply = socket.ReadLine();
if (!reply.StartsWith("250"))
{
OnError(SMTP_ErrorType.UnKnown, to, reply);
socket.SendLine("QUIT");
defectiveEmails.AddRange(to);
if (logger != null)
{
logger.Flush();
}
return(false);
}
}
#endregion
#region cmd QUIT
// Notify server - server can exit now
socket.SendLine("QUIT");
// reply = socket.ReadLine();
#endregion
}
catch (Exception x) {
OnError(SMTP_ErrorType.UnKnown, to, x.Message);
defectiveEmails.AddRange(to);
if (logger != null)
{
logger.Flush();
}
return(false);
}
finally{
// Raise event
OnSendJobCompleted(Thread.CurrentThread.GetHashCode().ToString(), to, defectiveEmails);
}
if (logger != null)
{
logger.Flush();
}
return(true);
}
