public static void Main(string[] args)
{
DnsServer server = null;
(new Thread(() => {
server = new DnsServer("8.8.8.8");
server.Responded += (request, response) => Console.WriteLine("{0} => {1}", request, response);
server.MasterFile.AddIPAddressResourceRecord("google.com", "127.0.0.1");
server.Listen();
})).Start();
Thread.Sleep(1000);
//Client client = new Client("72.21.204.209");
//Client client = new Client("8.8.8.8");
DnsClient client = new DnsClient("127.0.0.1");
client.Reverse(IPAddress.Parse("173.194.69.100"));
client.Lookup("google.com");
//client.Lookup("dr.dk");
//Console.WriteLine(client.Resolve("dnstest.managemydedi.com", RecordType.AAAA));
client.Lookup("cnn.com");
server.Close();
}
public static byte[] ByteRequest(string url)
{
Log.O("Downloading: " + url);
var wc = new WebClient();
if (_proxy != null)
{
wc.Proxy = _proxy;
}
var uri = new Uri(url);
if (!string.IsNullOrEmpty(_dns))
{
var host = uri.Host;
if (!_dnsCache.ContainsKey(host))
{
var dns = new DnsClient(_dns);
var resolved = dns.Lookup(host);
resolved.Wait();
_dnsCache[host] = resolved.Result.FirstOrDefault().ToString();
}
uri = uri.ReplaceHost(_dnsCache[host]);
wc.Headers.Add("Host", host);
}
return(wc.DownloadData(uri));
}
public async Task ClientNameError() {
DnsClient client = new DnsClient(new NameErrorRequestResolver());
await Assert.ThrowsAsync<ResponseException>(() => {
return client.Lookup("google.com");
});
}
private async Task <ResolvedDomain> Resolve(string domain)
{
var servers = await System.Net.Dns.GetHostAddressesAsync(_dnsServer);
var dnsServerIp = servers.First();
var mdl = new ResolvedDomain()
{
Name = domain, IsResolved = false
};
try
{
var client = new DnsClient(dnsServerIp);
var resp = await client.Lookup(_idnMapping.GetAscii(domain));
mdl.IsResolved = true;
mdl.IPAddresses = resp.Select(x => x.ToString()).ToHashSet();
return(mdl);
}
catch (Exception)
{
//Logger.Log($"[Resolve] fail {domain}", ex, LogType.INFO);
return(mdl);
}
}
/// <summary>
/// Gets the DNS records of a domain.
/// /// </summary>
/// <param name="domain">Domain to query for DNS records</param>
/// <param name="localDNSIPs">List of local DNS Resolver IPs to do the lookup</param>
/// <returns></returns>
public async Task <CollatedRecords> GetRecordsOfDomain(Uri domain, List <IPAddress> localDNSIPs)
{
IList <IPAddress> respIPs = new List <IPAddress>();
IResponse resp = null;
foreach (var dnsIP in localDNSIPs)
{
DnsClient cli = new DnsClient(dnsIP);
ClientRequest req = cli.Create();
req.RecursionDesired = true;
req.Questions.Add(new Question(Domain.FromString(domain.Host), RecordType.ANY));
try {
resp = await req.Resolve();
respIPs = await cli.Lookup(domain.Host);
} catch {
Console.Error.WriteLine("Swallowed lookup exception.");
}
if (resp != null && resp.ResponseCode.Equals(ResponseCode.NoError))
{
break;
}
}
if (resp == null)
{
throw new InvalidOperationException("Unable to get a valid response from the domain, check input.");
}
return(new CollatedRecords(resp, respIPs));
}
/// <summary>
/// Gets the DNS host entry (a list of IP addresses) for the domain name.
/// </summary>
/// <param name="fqdn">The FQDN.</param>
/// <param name="dnsServer">The DNS server.</param>
/// <param name="port">The port.</param>
/// <returns>
/// An array of local ip addresses of the result produced by this task.
/// </returns>
/// <exception cref="ArgumentNullException">fqdn.</exception>
public static async Task <IPAddress[]> GetDnsHostEntryAsync(string fqdn, IPAddress dnsServer, int port)
{
if (fqdn == null)
{
throw new ArgumentNullException(nameof(fqdn));
}
if (fqdn.IndexOf(".", StringComparison.Ordinal) == -1)
{
fqdn += "." + IPGlobalProperties.GetIPGlobalProperties().DomainName;
}
while (true)
{
if (!fqdn.EndsWith(".", StringComparison.OrdinalIgnoreCase))
{
break;
}
fqdn = fqdn.Substring(0, fqdn.Length - 1);
}
var client = new DnsClient(dnsServer, port);
var result = await client.Lookup(fqdn).ConfigureAwait(false);
return(result.ToArray());
}
public async Task ClientLookup() {
DnsClient client = new DnsClient(new IPAddressRequestResolver());
IList<IPAddress> ips = await client.Lookup("google.com");
Assert.Equal(1, ips.Count);
Assert.Equal("192.168.0.1", ips[0].ToString());
}
public async Task ParallelLookupTest()
{
DnsClient client = new DnsClient(new ParallelRequestResolver(new NameErrorRequestResolver(), new IPAddressRequestResolver()));
IList <IPAddress> ips = await client.Lookup("google.com");
Assert.Equal(1, ips.Count);
Assert.Equal("192.168.0.1", ips[0].ToString());
}
public IPAddress TryResolve(string hostname)
{
// Bind to a Domain Name Server
var client = new DnsClient("8.8.8.8");
// Returns a list of IPs
var ips = client.Lookup(hostname).Result;
return(ips.Count > 0 ? ips[0] : null);
}
public static void Main(string[] args)
{
DnsClient client = new DnsClient("8.8.8.8");
foreach (string domain in args)
{
IList <IPAddress> ips = client.Lookup(domain);
Console.WriteLine("{0} => {1}", domain, string.Join(", ", ips));
}
}
public async static Task MainAsync(string[] args)
{
DnsClient client = new DnsClient("8.8.8.8");
foreach (string domain in args)
{
IList <IPAddress> ips = await client.Lookup(domain).ConfigureAwait(false);
Console.WriteLine("{0} => {1}", domain, string.Join(", ", ips));
}
}
public async static Task LookupAsync(params string[] args)
{
DnsClient client = new DnsClient("127.0.0.1", 53);
foreach (string domain in args)
{
IList <IPAddress> ips = await client.Lookup(domain);
Console.WriteLine("[DNSClient] {0} => {1}", domain, string.Join(", ", ips));
}
}
public async static Task MainAsync()
{
MasterFile masterFile = new MasterFile();
DnsServer server = new DnsServer(masterFile, "8.8.8.8");
masterFile.AddIPAddressResourceRecord("google.com", "127.0.0.1");
server.Requested += (request) => Console.WriteLine("Requested: {0}", request);
server.Responded += (request, response) => Console.WriteLine("Responded: {0} => {1}", request, response);
server.Errored += (e) => Console.WriteLine("Errored: {0}", e.Message);
server.Listening += () => Console.WriteLine("Listening");
server.Listening += async() => {
DnsClient client = new DnsClient("127.0.0.1", PORT);
await client.Lookup("google.com");
await client.Lookup("cnn.com");
server.Dispose();
};
await server.Listen(PORT);
}
public static void Main(string[] args)
{
DnsServer server = null;
(new Thread(() => {
server = new DnsServer("8.8.8.8");
server.Requested += (request) => Console.WriteLine("Requested: {0}", request);
server.Responded += (request, response) => Console.WriteLine("Responded: {0} => {1}", request, response);
server.MasterFile.AddIPAddressResourceRecord("google.com", "127.0.0.1");
server.Listen();
})).Start();
Thread.Sleep(1000);
DnsClient client = new DnsClient("127.0.0.1");
client.Lookup("google.com");
client.Lookup("cnn.com");
server.Close();
}
public async static Task MainAsync()
{
DnsServer server = new DnsServer("8.8.8.8");
server.Requested += (request) => Console.WriteLine("Requested: {0}", request);
server.Responded += (request, response) => Console.WriteLine("Responded: {0} => {1}", request, response);
server.Errored += (e) => Console.WriteLine("Errored: {0}", e.Message);
server.MasterFile.AddIPAddressResourceRecord("google.com", "127.0.0.1");
#pragma warning disable 4014
server.Listen(PORT);
#pragma warning restore 4014
await Task.Delay(1000);
DnsClient client = new DnsClient("127.0.0.1", PORT);
await client.Lookup("google.com");
await client.Lookup("cnn.com");
server.Dispose();
}
public static string StringRequest(string url, string data)
{
var wc = new WebClient();
if (_proxy != null)
{
wc.Proxy = _proxy;
}
wc.Encoding = System.Text.Encoding.UTF8;
wc.Headers.Add("Content-Type", "text/plain; charset=utf8");
wc.Headers.Add("User-Agent", _userAgent);
var uri = new Uri(url);
if (!string.IsNullOrEmpty(_dns))
{
var host = uri.Host;
if (!_dnsCache.ContainsKey(host))
{
var dns = new DnsClient(_dns);
var resolved = dns.Lookup(host);
resolved.Wait();
_dnsCache[host] = resolved.Result.FirstOrDefault().ToString();
}
uri = uri.ReplaceHost(_dnsCache[host]);
wc.Headers.Add("Host", host);
}
string response = string.Empty;
try
{
response = wc.UploadString(uri, "POST", data);
}
catch (WebException wex)
{
Log.O("StringRequest Error: " + wex.ToString());
//Wait and Try again, just in case
Thread.Sleep(500);
response = wc.UploadString(uri, "POST", data);
}
return(response);
}
private ResponseItem Search(string query, RecordType recordType)
{
_logger.LogInformation($"Checking blacklisting for {query}");
var result = _cache.FirstOrDefault(c => c.Query.Equals(query));
if (result != null)
{
_logger.LogInformation("Cached item found");
return(result);
}
if (recordType != RecordType.A && recordType != RecordType.AAAA)
{
return(null);
}
foreach (var rbl in _rblList)
{
_logger.LogInformation($"Checking {rbl}");
try
{
var resolves = _dnsClient.Lookup($"{query}.{rbl}", recordType).Result;
if (!resolves.Any())
{
continue;
}
var rblMessage = SearchTxt($"{query}.{rbl}");
_logger.LogInformation("Found a match");
result = new ResponseItem(query, rbl, rblMessage?.ToStringTextData(), resolves.First());
_cache.Add(result);
return(result);
}
catch (Exception e)
{
// ignored
}
}
_logger.LogInformation("No matches found");
return(null);
}
public async Task ParallelLookupError()
{
DnsClient client = new DnsClient(new ParallelRequestResolver(new NameErrorRequestResolver(), new NameErrorRequestResolver(), new ThrowsExceptionRequestResolver(), new ThrowsExceptionRequestResolver()));
var responseException = await Assert.ThrowsAsync <ResponseException>(() =>
{
return(client.Lookup("google.com"));
});
client = new DnsClient(new ParallelRequestResolver(new ThrowsExceptionRequestResolver(), new ThrowsExceptionRequestResolver()));
var aggregateException = await Assert.ThrowsAsync <AggregateException>(() =>
{
return(client.Lookup("google.com"));
});
Assert.Equal(2, aggregateException.InnerExceptions.Count);
Assert.All(aggregateException.InnerExceptions, i => Assert.IsType <NotImplementedException>(i));
}
public async Task <IPAddress> TryResolve(string hostname)
{
IList <IPAddress> ips = null;
if (IPAddress.TryParse(hostname, out var address))
{
return(address);
}
try
{
ips = await _client.Lookup(hostname);
}
catch
{
// ignore
}
return(ips?.Count > 0 ? ips[0] : null);
}
static async void Run()
{
try
{
// Bind to a Domain Name Server
DnsClient client = new DnsClient("8.8.8.8");
// Create request bound to 8.8.8.8
ClientRequest request = client.Create();
// Returns a list of IPs
IList <IPAddress> ips = await client.Lookup("framesoft.ir");
// Get the domain name belonging to the IP (google.com)
//string domain = await client.Reverse("173.194.69.100");
}
catch (Exception ex)
{
}
}
/// <summary>
/// Gets the DNS host entry (a list of IP addresses) for the domain name.
/// </summary>
/// <param name="fqdn">The FQDN.</param>
/// <param name="dnsServer">The DNS server.</param>
/// <param name="port">The port.</param>
/// <returns>An array of local ip addresses</returns>
public static IPAddress[] GetDnsHostEntry(string fqdn, IPAddress dnsServer, int port)
{
if (fqdn.IndexOf(".", StringComparison.Ordinal) == -1)
{
fqdn += "." + IPGlobalProperties.GetIPGlobalProperties().DomainName;
}
while (true)
{
if (fqdn.EndsWith(".") == false)
{
break;
}
fqdn = fqdn.Substring(0, fqdn.Length - 1);
}
var client = new DnsClient(dnsServer, port);
var result = client.Lookup(fqdn);
return(result.ToArray());
}
public static bool IsDkimSettedUpCorrectForDomain(string domain_name, string selector, string dkim_record, ILogger logger = null)
{
try
{
var domain_txt_records = DnsClient.Lookup(selector + "._domainkey." + domain_name, DnsClient.RecordType.TXT);
if (domain_txt_records == null)
{
throw new ArgumentException("DKIM record on your domain is missing.");
}
return(domain_txt_records.AnswerRecords.Any(re => re.Data.Trim('\"') == dkim_record));
}
catch (Exception ex)
{
if (logger != null)
{
logger.Debug("DnsClient.Lookup: domain: '{0}' selector: '{1}._domainkey.' dkim_pk: '{2}'\r\nException: {3}",
domain_name, selector, dkim_record, ex.ToString());
}
return(false);
}
}
public static bool IsTxtRecordCorrect(string domain_name, string txt_record, ILogger logger = null)
{
try
{
var domain_txt_records = DnsClient.Lookup(domain_name, DnsClient.RecordType.TXT);
if (domain_txt_records == null)
{
throw new ArgumentException("TXT record on your domain is missing.");
}
return(domain_txt_records.AnswerRecords.Any(re => re.Data.Trim('\"') == txt_record));
}
catch (Exception ex)
{
if (logger != null)
{
logger.Debug("DnsClient.LookupMX: domain: '{0}' txt: '{1}'\r\nException: {2}",
domain_name, txt_record, ex.ToString());
}
return(false);
}
}
/// <summary>
/// Detects whether our DNS servers are down.
///
/// This one's a little sticky because we don't know whether internet is down for sure.
/// I think it's easy enough to just assume that if we can't reach our DNS servers we should probably flip the switch.
///
/// If first server checked is up, no more are checked, and so on.
/// </summary>
/// <returns>Returns true if at least one of the servers in the configuration returns a response or if there are none configured. Returns false if all servers tried do not return a response.</returns>
public async Task <bool> IsDnsUp()
{
if (lastDnsCheck.AddMinutes(5) > DateTime.Now)
{
return(lastDnsResult);
}
lastDnsCheck = DateTime.Now;
bool ret = false;
if (m_provider.Config == null)
{
// We can't really make a decision on enforcement here, but just return true anyway.
return(true);
}
string primaryDns = m_provider.Config.PrimaryDns;
string secondaryDns = m_provider.Config.SecondaryDns;
if (string.IsNullOrWhiteSpace(primaryDns) && string.IsNullOrWhiteSpace(secondaryDns))
{
ret = true;
}
else
{
List <string> dnsSearch = new List <string>();
if (!string.IsNullOrWhiteSpace(primaryDns))
{
dnsSearch.Add(primaryDns);
}
if (!string.IsNullOrWhiteSpace(secondaryDns))
{
dnsSearch.Add(secondaryDns);
}
int failedDnsServers = 0;
foreach (string dnsServer in dnsSearch)
{
try
{
DnsClient client = new DnsClient(dnsServer);
IList <IPAddress> ips = await client.Lookup("testdns.cloudveil.org");
if (ips != null && ips.Count > 0)
{
ret = true;
break;
}
else
{
failedDnsServers++;
}
}
catch (Exception ex)
{
failedDnsServers++;
m_logger.Error($"Failed to contact DNS server {dnsServer}");
LoggerUtil.RecursivelyLogException(m_logger, ex);
}
}
}
lastDnsResult = ret;
return(ret);
}
