public static SIPDNSLookupResult DNSAAAARecordLookup(string host, int port, bool async, SIPURI uri, SIPDNSLookupResult lookupResult = null)
{
SIPMonitorLogEvent(new SIPMonitorConsoleEvent(SIPMonitorServerTypesEnum.Unknown, SIPMonitorEventTypesEnum.DNS, "SIP DNS A record lookup requested for " + host + ".", null));
SIPDNSLookupResult result = lookupResult ?? new SIPDNSLookupResult(uri);
result.LookupError = null;
DNSResponse aaaaRecordResponse = DNSManager.Lookup(host, QType.AAAA, DNS_A_RECORD_LOOKUP_TIMEOUT, null, true, async);
if (aaaaRecordResponse == null)
{
if (async)
{
result.Pending = true;
}
}
else if (aaaaRecordResponse.Timedout)
{
result.ATimedoutAt = DateTime.Now;
}
else if (!string.IsNullOrWhiteSpace(aaaaRecordResponse.Error))
{
result.LookupError = aaaaRecordResponse.Error;
}
else if (aaaaRecordResponse.RecordsAAAA == null || aaaaRecordResponse.RecordsAAAA.Length == 0)
{
SIPMonitorLogEvent(new SIPMonitorConsoleEvent(SIPMonitorServerTypesEnum.Unknown, SIPMonitorEventTypesEnum.DNS, "SIP DNS no AAAA records found for " + host + ".", null));
result.LookupError = "No AAAA records found for " + host + ".";
}
else
{
SIPURI sipURI = result.URI;
foreach (RecordAAAA aRecord in aaaaRecordResponse.RecordsAAAA)
{
SIPDNSLookupEndPoint sipLookupEndPoint = new SIPDNSLookupEndPoint(new SIPEndPoint(sipURI.Protocol, new IPEndPoint(aRecord.Address, port)), aRecord.RR.TTL);
result.AddLookupResult(sipLookupEndPoint);
SIPMonitorLogEvent(new SIPMonitorConsoleEvent(SIPMonitorServerTypesEnum.Unknown, SIPMonitorEventTypesEnum.DNS, "SIP DNS AAAA record found for " + host + ", result " + sipLookupEndPoint.LookupEndPoint.ToString() + ".", null));
}
}
return(result);
}
public static SIPDNSLookupResult ResolveSIPService(SIPURI sipURI, bool async)
{
try
{
if (sipURI == null)
{
throw new ArgumentNullException("sipURI", "Cannot resolve SIP service on a null URI.");
}
string host = sipURI.Host;
int port = (sipURI.Scheme == SIPSchemesEnum.sip) ? m_defaultSIPPort : m_defaultSIPSPort;
bool explicitPort = false;
if (sipURI.Host.IndexOf(':') != -1)
{
host = sipURI.Host.Split(':')[0];
Int32.TryParse(sipURI.Host.Split(':')[1], out port);
explicitPort = true;
}
if (Regex.Match(host, @"^\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}$").Success)
{
// Target is an IP address, no DNS lookup required.
IPAddress hostIP = IPAddress.Parse(host);
SIPDNSLookupEndPoint sipLookupEndPoint = new SIPDNSLookupEndPoint(new SIPEndPoint(sipURI.Protocol, new IPEndPoint(hostIP, port)), 0);
SIPDNSLookupResult result = new SIPDNSLookupResult(sipURI);
result.AddLookupResult(sipLookupEndPoint);
return result;
}
else if (explicitPort)
{
// Target is a hostname with an explicit port, DNS lookup for A or AAAA record.
return DNSARecordLookup(host, port, async, sipURI);
}
else
{
// Target is a hostname with no explicit port, use the whole NAPTR->SRV->A lookup procedure.
SIPDNSLookupResult sipLookupResult = new SIPDNSLookupResult(sipURI);
// Do without the NAPTR lookup for the time being. Very few organisations appear to use them and it can cost up to 2.5s to get a failed resolution.
/*SIPMonitorLogEvent(new SIPMonitorConsoleEvent(SIPMonitorServerTypesEnum.Unknown, SIPMonitorEventTypesEnum.DNS, "SIP DNS full lookup requested for " + sipURI.ToString() + ".", null));
DNSNAPTRRecordLookup(host, async, ref sipLookupResult);
if (sipLookupResult.Pending)
{
if (!m_inProgressSIPServiceLookups.Contains(sipURI.ToString()))
{
m_inProgressSIPServiceLookups.Add(sipURI.ToString());
ThreadPool.QueueUserWorkItem(delegate { ResolveSIPService(sipURI, false); });
}
return sipLookupResult;
}*/
DNSSRVRecordLookup(sipURI.Scheme, sipURI.Protocol, host, async, ref sipLookupResult);
if (sipLookupResult.Pending)
{
//logger.Debug("SIPDNSManager SRV lookup for " + host + " is pending.");
return sipLookupResult;
}
else
{
//logger.Debug("SIPDNSManager SRV lookup for " + host + " is final.");
SIPDNSServiceResult nextSRVRecord = sipLookupResult.GetNextUnusedSRV();
int lookupPort = (nextSRVRecord != null) ? nextSRVRecord.Port : port;
return DNSARecordLookup(nextSRVRecord, host, lookupPort, async, sipLookupResult.URI);
}
}
}
catch (Exception excp)
{
logger.Error("Exception SIPDNSManager ResolveSIPService (" + sipURI.ToString() + "). " + excp.Message);
m_inProgressSIPServiceLookups.Remove(sipURI.ToString());
return new SIPDNSLookupResult(sipURI, excp.Message);
}
}
public static SIPDNSLookupResult DNSARecordLookup(string host, int port, bool async, SIPURI uri)
{
SIPMonitorLogEvent(new SIPMonitorConsoleEvent(SIPMonitorServerTypesEnum.Unknown, SIPMonitorEventTypesEnum.DNS, "SIP DNS A record lookup requested for " + host + ".", null));
SIPDNSLookupResult result = new SIPDNSLookupResult(uri);
DNSResponse aRecordResponse = DNSManager.Lookup(host, DNSQType.A, DNS_A_RECORD_LOOKUP_TIMEOUT, null, true, async);
if (aRecordResponse == null && async)
{
result.Pending = true;
}
else if (aRecordResponse.Timedout)
{
result.ATimedoutAt = DateTime.Now;
}
else if (aRecordResponse.Error != null)
{
result.LookupError = aRecordResponse.Error;
}
else if (aRecordResponse.RecordsA == null || aRecordResponse.RecordsA.Length == 0)
{
SIPMonitorLogEvent(new SIPMonitorConsoleEvent(SIPMonitorServerTypesEnum.Unknown, SIPMonitorEventTypesEnum.DNS, "SIP DNS no A records found for " + host + ".", null));
result.LookupError = "No A records found for " + host + ".";
}
else
{
SIPURI sipURI = result.URI;
foreach (RecordA aRecord in aRecordResponse.RecordsA)
{
SIPDNSLookupEndPoint sipLookupEndPoint = new SIPDNSLookupEndPoint(new SIPEndPoint(sipURI.Protocol, new IPEndPoint(aRecord.Address, port)), aRecord.RR.TTL);
result.AddLookupResult(sipLookupEndPoint);
SIPMonitorLogEvent(new SIPMonitorConsoleEvent(SIPMonitorServerTypesEnum.Unknown, SIPMonitorEventTypesEnum.DNS, "SIP DNS A record found for " + host + ", result " + sipLookupEndPoint.LookupEndPoint.ToString() + ".", null));
}
}
return result;
}
public static SIPDNSLookupResult ResolveSIPService(SIPURI sipURI, bool async)
{
try
{
if (sipURI == null)
{
throw new ArgumentNullException("sipURI", "Cannot resolve SIP service on a null URI.");
}
string host = sipURI.Host;
int port = (sipURI.Scheme == SIPSchemesEnum.sip) ? m_defaultSIPPort : m_defaultSIPSPort;
bool explicitPort = false;
if (sipURI.Host.IndexOf(':') != -1)
{
host = sipURI.Host.Split(':')[0];
Int32.TryParse(sipURI.Host.Split(':')[1], out port);
explicitPort = true;
}
if (Regex.Match(host, @"^\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}$").Success)
{
// Target is an IP address, no DNS lookup required.
IPAddress hostIP = IPAddress.Parse(host);
SIPDNSLookupEndPoint sipLookupEndPoint = new SIPDNSLookupEndPoint(new SIPEndPoint(sipURI.Protocol, new IPEndPoint(hostIP, port)), 0);
SIPDNSLookupResult result = new SIPDNSLookupResult(sipURI);
result.AddLookupResult(sipLookupEndPoint);
return(result);
}
else if (explicitPort)
{
// Target is a hostname with an explicit port, DNS lookup for A or AAAA record.
return(DNSARecordLookup(host, port, async, sipURI));
}
else
{
// Target is a hostname with no explicit port, use the whole NAPTR->SRV->A lookup procedure.
SIPDNSLookupResult sipLookupResult = new SIPDNSLookupResult(sipURI);
// Do without the NAPTR lookup for the time being. Very few organisations appear to use them and it can cost up to 2.5s to get a failed resolution.
/*SIPMonitorLogEvent(new SIPMonitorConsoleEvent(SIPMonitorServerTypesEnum.Unknown, SIPMonitorEventTypesEnum.DNS, "SIP DNS full lookup requested for " + sipURI.ToString() + ".", null));
* DNSNAPTRRecordLookup(host, async, ref sipLookupResult);
* if (sipLookupResult.Pending)
* {
* if (!m_inProgressSIPServiceLookups.Contains(sipURI.ToString()))
* {
* m_inProgressSIPServiceLookups.Add(sipURI.ToString());
* ThreadPool.QueueUserWorkItem(delegate { ResolveSIPService(sipURI, false); });
* }
* return sipLookupResult;
* }*/
DNSSRVRecordLookup(sipURI.Scheme, sipURI.Protocol, host, async, ref sipLookupResult);
if (sipLookupResult.Pending)
{
//logger.Debug("SIPDNSManager SRV lookup for " + host + " is pending.");
return(sipLookupResult);
}
else
{
//logger.Debug("SIPDNSManager SRV lookup for " + host + " is final.");
// Add some custom logic to cope with sips SRV records using _sips._tcp (e.g. free.call.ciscospark.com).
// By default only _sips._tls SRV records are checked for. THis block adds an additional check for _sips._tcp SRV records.
//if ((sipLookupResult.SIPSRVResults == null || sipLookupResult.SIPSRVResults.Count == 0) && sipURI.Scheme == SIPSchemesEnum.sips)
//{
// DNSSRVRecordLookup(sipURI.Scheme, SIPProtocolsEnum.tcp, host, async, ref sipLookupResult);
// SIPDNSServiceResult nextSRVRecord = sipLookupResult.GetNextUnusedSRV();
// int lookupPort = (nextSRVRecord != null) ? nextSRVRecord.Port : port;
// return DNSARecordLookup(nextSRVRecord, host, lookupPort, async, sipLookupResult.URI);
//}
//else
//{
SIPDNSServiceResult nextSRVRecord = sipLookupResult.GetNextUnusedSRV();
int lookupPort = (nextSRVRecord != null) ? nextSRVRecord.Port : port;
return(DNSARecordLookup(nextSRVRecord, host, lookupPort, async, sipLookupResult.URI));
//}
}
}
}
catch (Exception excp)
{
logger.Error("Exception SIPDNSManager ResolveSIPService (" + sipURI.ToString() + "). " + excp.Message);
m_inProgressSIPServiceLookups.Remove(sipURI.ToString());
return(new SIPDNSLookupResult(sipURI, excp.Message));
}
}
public static SIPDNSLookupResult DNSNameRecordLookup(string host, int port, bool async, SIPURI uri, SIPDNSLookupResult lookupResult = null, bool?preferIPv6 = null, int recursionLevel = 0)
{
SIPMonitorLogEvent(new SIPMonitorConsoleEvent(SIPMonitorServerTypesEnum.Unknown, SIPMonitorEventTypesEnum.DNS, "SIP DNS Name record lookup requested for " + host + ".", null));
SIPDNSLookupResult result = lookupResult ?? new SIPDNSLookupResult(uri);
result.LookupError = null;
if (UseANYLookups)
{
DNSResponse aRecordResponse = DNSManager.Lookup(host, QType.ANY, DNS_A_RECORD_LOOKUP_TIMEOUT, null, true, async);
if (aRecordResponse == null && async)
{
result.Pending = true;
}
else if (aRecordResponse == null)
{
}
else if (aRecordResponse.Timedout)
{
result.ATimedoutAt = DateTime.Now;
}
else if (!string.IsNullOrWhiteSpace(aRecordResponse.Error))
{
result.LookupError = aRecordResponse.Error;
}
else if ((aRecordResponse.RecordsAAAA == null || aRecordResponse.RecordsAAAA.Length == 0) && (aRecordResponse.RecordsA == null || aRecordResponse.RecordsA.Length == 0) && (aRecordResponse.RecordsCNAME == null || aRecordResponse.RecordsCNAME.Length == 0))
{
SIPMonitorLogEvent(new SIPMonitorConsoleEvent(SIPMonitorServerTypesEnum.Unknown, SIPMonitorEventTypesEnum.DNS, "SIP DNS no CNAME, A or AAAA records found for " + host + ".", null));
result.LookupError = "No CNAME, A or AAAA records found for " + host + ".";
}
else
{
if (preferIPv6 == null)
{
preferIPv6 = SIPDNSManager.PreferIPv6NameResolution;
}
foreach (RecordCNAME aRecord in aRecordResponse.RecordsCNAME)
{
//CNAME could be another CNAME or A/AAAA Record -> max 3 levels recursive name resolution
if (recursionLevel < 3)
{
SIPDNSLookupResult resultCName = DNSNameRecordLookup(aRecord.CNAME, port, async, uri, lookupResult, preferIPv6, recursionLevel + 1);
if (resultCName != null)
{
foreach (SIPDNSLookupEndPoint ep in resultCName.EndPointResults)
{
result.AddLookupResult(ep);
}
}
}
}
if (preferIPv6 == true)
{
SIPURI sipURI = result.URI;
foreach (RecordAAAA aRecord in aRecordResponse.RecordsAAAA)
{
SIPDNSLookupEndPoint sipLookupEndPoint = new SIPDNSLookupEndPoint(new SIPEndPoint(sipURI.Protocol, new IPEndPoint(aRecord.Address, port)), aRecord.RR.TTL);
result.AddLookupResult(sipLookupEndPoint);
SIPMonitorLogEvent(new SIPMonitorConsoleEvent(SIPMonitorServerTypesEnum.Unknown, SIPMonitorEventTypesEnum.DNS, "SIP DNS AAAA record found for " + host + ", result " + sipLookupEndPoint.LookupEndPoint.ToString() + ".", null));
}
foreach (RecordA aRecord in aRecordResponse.RecordsA)
{
SIPDNSLookupEndPoint sipLookupEndPoint = new SIPDNSLookupEndPoint(new SIPEndPoint(sipURI.Protocol, new IPEndPoint(aRecord.Address, port)), aRecord.RR.TTL);
result.AddLookupResult(sipLookupEndPoint);
SIPMonitorLogEvent(new SIPMonitorConsoleEvent(SIPMonitorServerTypesEnum.Unknown, SIPMonitorEventTypesEnum.DNS, "SIP DNS A record found for " + host + ", result " + sipLookupEndPoint.LookupEndPoint.ToString() + ".", null));
}
}
else
{
SIPURI sipURI = result.URI;
foreach (RecordA aRecord in aRecordResponse.RecordsA)
{
SIPDNSLookupEndPoint sipLookupEndPoint = new SIPDNSLookupEndPoint(new SIPEndPoint(sipURI.Protocol, new IPEndPoint(aRecord.Address, port)), aRecord.RR.TTL);
result.AddLookupResult(sipLookupEndPoint);
SIPMonitorLogEvent(new SIPMonitorConsoleEvent(SIPMonitorServerTypesEnum.Unknown, SIPMonitorEventTypesEnum.DNS, "SIP DNS A record found for " + host + ", result " + sipLookupEndPoint.LookupEndPoint.ToString() + ".", null));
}
foreach (RecordAAAA aRecord in aRecordResponse.RecordsAAAA)
{
SIPDNSLookupEndPoint sipLookupEndPoint = new SIPDNSLookupEndPoint(new SIPEndPoint(sipURI.Protocol, new IPEndPoint(aRecord.Address, port)), aRecord.RR.TTL);
result.AddLookupResult(sipLookupEndPoint);
SIPMonitorLogEvent(new SIPMonitorConsoleEvent(SIPMonitorServerTypesEnum.Unknown, SIPMonitorEventTypesEnum.DNS, "SIP DNS AAAA record found for " + host + ", result " + sipLookupEndPoint.LookupEndPoint.ToString() + ".", null));
}
}
}
}
if (result.LookupError != null || result.EndPointResults == null || result.EndPointResults.Count == 0)
{
if (preferIPv6 == true)
{
result = DNSAAAARecordLookup(host, port, async, uri, lookupResult);
}
else
{
result = DNSARecordLookup(host, port, async, uri, lookupResult);
}
}
return(result);
}
// TODO: Remove this nasty code duplication with ResolveSIPService!
public static async Task <SIPDNSLookupResult> ResolveAsync(SIPURI sipURI, bool?preferIPv6 = null)
{
try
{
if (sipURI == null)
{
throw new ArgumentNullException("sipURI", "Cannot resolve SIP service on a null URI.");
}
if (IPSocket.TryParseIPEndPoint(sipURI.MAddrOrHost, out var ipEndPoint))
{
// Target is an IP address, no DNS lookup required.
SIPDNSLookupEndPoint sipLookupEndPoint = new SIPDNSLookupEndPoint(new SIPEndPoint(sipURI.Protocol, ipEndPoint), 0);
SIPDNSLookupResult result = new SIPDNSLookupResult(sipURI);
result.AddLookupResult(sipLookupEndPoint);
return(result);
}
else
{
string host = sipURI.MAddrOrHostAddress;
//int port = IPSocket.ParsePortFromSocket(host);
int port = sipURI.Protocol != SIPProtocolsEnum.tls ? m_defaultSIPPort : m_defaultSIPSPort;
if (preferIPv6 == null)
{
preferIPv6 = SIPDNSManager.PreferIPv6NameResolution;
}
bool explicitPort = false;
try
{
//Parse returns true if sipURI.Host can be parsed as an ipaddress
bool parseresult = SIPSorcery.Sys.IPSocket.Parse(sipURI.MAddrOrHost, out host, out port);
explicitPort = port >= 0;
if (!explicitPort)
{
//port = (sipURI.Scheme == SIPSchemesEnum.sip) ? m_defaultSIPPort : m_defaultSIPSPort;
port = sipURI.Protocol != SIPProtocolsEnum.tls ? m_defaultSIPPort : m_defaultSIPSPort;
}
if (parseresult == true)
{
IPAddress hostIP = IPAddress.Parse(host);
SIPDNSLookupEndPoint sipLookupEndPoint = new SIPDNSLookupEndPoint(new SIPEndPoint(sipURI.Protocol, new IPEndPoint(hostIP, port)), 0);
SIPDNSLookupResult result = new SIPDNSLookupResult(sipURI);
result.AddLookupResult(sipLookupEndPoint);
return(result);
}
}
catch (Exception ex)
{
SIPMonitorLogEvent(new SIPMonitorConsoleEvent(SIPMonitorServerTypesEnum.Unknown, SIPMonitorEventTypesEnum.DNS, "Exception SIPDNSManager ResolveSIPService (" + sipURI.ToString() + "). " + ex, null));
//rj2: if there is a parsing exception, then fallback to original sipsorcery parsing mechanism
port = IPSocket.ParsePortFromSocket(sipURI.Host);
explicitPort = port > 0;
//if(Regex.Match(host, @"^\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}$").Success)
if (SIPSorcery.Sys.IPSocket.IsIPAddress(host))
{
// Target is an IP address, no DNS lookup required.
IPAddress hostIP = IPAddress.Parse(host);
SIPDNSLookupEndPoint sipLookupEndPoint = new SIPDNSLookupEndPoint(new SIPEndPoint(sipURI.Protocol, new IPEndPoint(hostIP, port)), 0);
SIPDNSLookupResult result = new SIPDNSLookupResult(sipURI);
result.AddLookupResult(sipLookupEndPoint);
return(result);
}
}
if (!explicitPort)
{
//port = (sipURI.Scheme == SIPSchemesEnum.sip) ? m_defaultSIPPort : m_defaultSIPSPort;
port = sipURI.Protocol != SIPProtocolsEnum.tls ? m_defaultSIPPort : m_defaultSIPSPort;
}
if (host.Contains(".") == false || IPSocket.ParseHostFromSocket(host).EndsWith(MDNS_TLD))
{
string hostOnly = IPSocket.ParseHostFromSocket(host);
// If host is not fully qualified then assume there's no point using NAPTR or SRV record look ups and go straight to A's.
if (hostOnly.ToLower() == System.Net.Dns.GetHostName()?.ToLower())
{
// The lookup is for the current machine.
var addressList = System.Net.Dns.GetHostEntry(System.Net.Dns.GetHostName()).AddressList;
if (addressList?.Length == 0)
{
return(new SIPDNSLookupResult(sipURI, $"Failed to resolve local machine hostname."));
}
else
{
// Preference for IPv4 IP address for local host name lookup.
IPAddress firstAddress = addressList.Where(x => x.AddressFamily == (preferIPv6 == true ? AddressFamily.InterNetworkV6 : AddressFamily.InterNetwork)).FirstOrDefault() ?? addressList.FirstOrDefault();
SIPEndPoint resultEp = new SIPEndPoint(sipURI.Protocol, new IPEndPoint(firstAddress, port));
return(new SIPDNSLookupResult(sipURI, resultEp));
}
}
else
{
return(await Task.Run(() => DNSNameRecordLookup(hostOnly, port, false, sipURI, null, preferIPv6)).ConfigureAwait(false));
}
}
else if (explicitPort)
{
// If target is a hostname with an explicit port then SIP lookup rules state to use DNS lookup for A or AAAA record.
host = host.Substring(0, host.LastIndexOf(':'));
return(await Task.Run(() => DNSNameRecordLookup(host, port, false, sipURI, null, preferIPv6)).ConfigureAwait(false));
}
else
{
// Target is a hostname with no explicit port, use the whole NAPTR->SRV->A lookup procedure.
SIPDNSLookupResult sipLookupResult = new SIPDNSLookupResult(sipURI);
// Do without the NAPTR lookup for the time being. Very few organisations appear to use them and it can cost up to 2.5s to get a failed resolution.
//rj2: uncomment this section for telekom 1TR118 lookup
SIPMonitorLogEvent(new SIPMonitorConsoleEvent(SIPMonitorServerTypesEnum.Unknown, SIPMonitorEventTypesEnum.DNS, "SIP DNS full lookup requested for " + sipURI.ToString() + ".", null));
DNSNAPTRRecordLookup(host, false, ref sipLookupResult);
if (sipLookupResult.Pending)
{
if (!m_inProgressSIPServiceLookups.Contains(sipURI.ToString()))
{
m_inProgressSIPServiceLookups.Add(sipURI.ToString());
//ThreadPool.QueueUserWorkItem(delegate { ResolveSIPService(sipURI, false); });
System.Threading.ThreadPool.QueueUserWorkItem((obj) => ResolveSIPService(sipURI, false, preferIPv6));
}
return(sipLookupResult);
}
return(await Task.Run(() =>
{
DNSSRVRecordLookup(sipURI.Scheme, sipURI.Protocol, host, false, ref sipLookupResult);
if (sipLookupResult.Pending)
{
//logger.LogDebug("SIPDNSManager SRV lookup for " + host + " is pending.");
return sipLookupResult;
}
else
{
//logger.LogDebug("SIPDNSManager SRV lookup for " + host + " is final.");
// Add some custom logic to cope with sips SRV records using _sips._tcp (e.g. free.call.ciscospark.com).
// By default only _sips._tls SRV records are checked for. THis block adds an additional check for _sips._tcp SRV records.
//if ((sipLookupResult.SIPSRVResults == null || sipLookupResult.SIPSRVResults.Count == 0) && sipURI.Scheme == SIPSchemesEnum.sips)
//{
// DNSSRVRecordLookup(sipURI.Scheme, SIPProtocolsEnum.tcp, host, async, ref sipLookupResult);
// SIPDNSServiceResult nextSRVRecord = sipLookupResult.GetNextUnusedSRV();
// int lookupPort = (nextSRVRecord != null) ? nextSRVRecord.Port : port;
// return DNSARecordLookup(nextSRVRecord, host, lookupPort, async, sipLookupResult.URI);
//}
//else
//{
// SIPDNSServiceResult nextSRVRecord = sipLookupResult.GetNextUnusedSRV();
// int lookupPort = (nextSRVRecord != null) ? nextSRVRecord.Port : port;
// return DNSARecordLookup(nextSRVRecord, host, lookupPort, false, sipLookupResult.URI);
//}
// The SRV record can indicate the SIP server is using a non-standard port.
SIPDNSServiceResult nextSRVRecord = sipLookupResult.GetNextUnusedSRV();
int lookupPort = (nextSRVRecord != null) ? nextSRVRecord.Port : port;
return DNSNameRecordLookup(host, lookupPort, false, sipLookupResult.URI, ref sipLookupResult, preferIPv6);
}
}).ConfigureAwait(false));
}
}
}
catch (Exception excp)
{
logger.LogError("Exception SIPDNSManager ResolveSIPService (" + sipURI.ToString() + "). " + excp.Message);
m_inProgressSIPServiceLookups.Remove(sipURI.ToString());
return(new SIPDNSLookupResult(sipURI, excp.Message));
}
}
public static SIPDNSLookupResult ResolveSIPService(SIPURI sipURI, bool async)
{
try
{
if (sipURI == null)
{
throw new ArgumentNullException("sipURI", "Cannot resolve SIP service on a null URI.");
}
if (IPSocket.TryParseIPEndPoint(sipURI.Host, out var ipEndPoint))
{
// Target is an IP address, no DNS lookup required.
SIPDNSLookupEndPoint sipLookupEndPoint = new SIPDNSLookupEndPoint(new SIPEndPoint(sipURI.Protocol, ipEndPoint), 0);
SIPDNSLookupResult result = new SIPDNSLookupResult(sipURI);
result.AddLookupResult(sipLookupEndPoint);
return(result);
}
else
{
string host = sipURI.Host;
int port = IPSocket.ParsePortFromSocket(sipURI.Host);
bool explicitPort = (port != 0);
if (!explicitPort)
{
port = (sipURI.Scheme == SIPSchemesEnum.sip) ? m_defaultSIPPort : m_defaultSIPSPort;
}
if (host.Contains(".") == false)
{
string hostOnly = IPSocket.ParseHostFromSocket(host);
// If host is not fully qualified then assume there's no point using NAPTR or SRV record look ups and go straight to A's.
if (hostOnly.ToLower() == System.Net.Dns.GetHostName()?.ToLower())
{
// The lookup is for the current machine.
var addressList = System.Net.Dns.GetHostEntry(System.Net.Dns.GetHostName()).AddressList;
if (addressList?.Length == 0)
{
return(new SIPDNSLookupResult(sipURI, $"Failed to resolve local machine hostname."));
}
else
{
// Preference for IPv4 IP address for local host anem lookup.
IPAddress firstAddress = addressList.Where(x => x.AddressFamily == AddressFamily.InterNetwork).FirstOrDefault() ?? addressList.FirstOrDefault();
SIPEndPoint resultEp = new SIPEndPoint(sipURI.Protocol, new IPEndPoint(firstAddress, port));
return(new SIPDNSLookupResult(sipURI, resultEp));
}
}
else
{
return(DNSARecordLookup(hostOnly, port, async, sipURI));
}
}
else if (explicitPort)
{
// If target is a hostname with an explicit port then SIP lookup rules state to use DNS lookup for A or AAAA record.
host = host.Substring(0, host.LastIndexOf(':'));
return(DNSARecordLookup(host, port, async, sipURI));
}
else
{
// Target is a hostname with no explicit port, use the whole NAPTR->SRV->A lookup procedure.
SIPDNSLookupResult sipLookupResult = new SIPDNSLookupResult(sipURI);
// Do without the NAPTR lookup for the time being. Very few organisations appear to use them and it can cost up to 2.5s to get a failed resolution.
/*SIPMonitorLogEvent(new SIPMonitorConsoleEvent(SIPMonitorServerTypesEnum.Unknown, SIPMonitorEventTypesEnum.DNS, "SIP DNS full lookup requested for " + sipURI.ToString() + ".", null));
* DNSNAPTRRecordLookup(host, async, ref sipLookupResult);
* if (sipLookupResult.Pending)
* {
* if (!m_inProgressSIPServiceLookups.Contains(sipURI.ToString()))
* {
* m_inProgressSIPServiceLookups.Add(sipURI.ToString());
* ThreadPool.QueueUserWorkItem(delegate { ResolveSIPService(sipURI, false); });
* }
* return sipLookupResult;
* }*/
DNSSRVRecordLookup(sipURI.Scheme, sipURI.Protocol, host, async, ref sipLookupResult);
if (sipLookupResult.Pending)
{
//logger.LogDebug("SIPDNSManager SRV lookup for " + host + " is pending.");
return(sipLookupResult);
}
else
{
//logger.LogDebug("SIPDNSManager SRV lookup for " + host + " is final.");
// Add some custom logic to cope with sips SRV records using _sips._tcp (e.g. free.call.ciscospark.com).
// By default only _sips._tls SRV records are checked for. THis block adds an additional check for _sips._tcp SRV records.
//if ((sipLookupResult.SIPSRVResults == null || sipLookupResult.SIPSRVResults.Count == 0) && sipURI.Scheme == SIPSchemesEnum.sips)
//{
// DNSSRVRecordLookup(sipURI.Scheme, SIPProtocolsEnum.tcp, host, async, ref sipLookupResult);
// SIPDNSServiceResult nextSRVRecord = sipLookupResult.GetNextUnusedSRV();
// int lookupPort = (nextSRVRecord != null) ? nextSRVRecord.Port : port;
// return DNSARecordLookup(nextSRVRecord, host, lookupPort, async, sipLookupResult.URI);
//}
//else
//{
SIPDNSServiceResult nextSRVRecord = sipLookupResult.GetNextUnusedSRV();
int lookupPort = (nextSRVRecord != null) ? nextSRVRecord.Port : port;
return(DNSARecordLookup(nextSRVRecord, host, lookupPort, async, sipLookupResult.URI));
//}
}
}
}
}
catch (Exception excp)
{
logger.LogError("Exception SIPDNSManager ResolveSIPService (" + sipURI.ToString() + "). " + excp.Message);
m_inProgressSIPServiceLookups.Remove(sipURI.ToString());
return(new SIPDNSLookupResult(sipURI, excp.Message));
}
}