#include <NatMaintainer.h>
This pinhole is maintained open by the NAT/FW until the traffic flowing through it stops. sipXecs requires this pinhole to be maintained open so that it can send SIP messages to the User Agent behind the NAT/FW. To that end, the NAT Traversal feature includes a component that will periodically send a SIP message to every UA known to the system that is behind a NAT. Basically, sipXecs needs to maintain pinholes for every endpoint behind a NAT/FW that it may send messages to. These endpoints are: 1. REMOTE_NATED endpoints that are registered to sipXecs: On an incoming call to such endpoints, sipXecs will have to send an INVITE to their public IP:port therefore requiring the pinhole to be open; 2. REMOTE_NATED endpoints that have active subscriptions on the sipXecs: sipXecs will need to send NOTIFY messages to these endpoints’ public IP:port therefore requiring the pinhole to be open; 3. REMOTE_NATED endpoints that are involved in a call: While on a call, an endpoint behind a remote NAT may be the recipient of in-dialog requests which will be sent to their public IP:Port therefore requiring the pinhole to be open. In non-HA deployments, item #1 is a superset of items #2 and #3 however in HA deployments these items are not fully overlapping so to ensure full coverage, all three items must be considered by the pinhole-maintaining component. That NatMaintainer is a class implemented in code unit ‘NatMaintainer.cpp’ and is responsible for maintaining NAT pinholes alive. An instance of the NatMaintainer class is created by NatTraveralAgent only when the NAT Traversal feature is enabled. The list of pinholes that it needs to maintain is built from three sources: 1. Registration DB: NatMaintainer queries the registration DB looking for unexpired contacts that containing a ‘x-sipX-privcontact’ URL parameter. 2. Subscription DB: NatMaintainer queries the subscription DB looking for unexpired contacts that containing a ‘x-sipX-privcontact’ URL parameter. 3. External Pinhole List: NatMaintainer exposes methods to be invoked by components of the NAT Traversal feature to dynamically add and remove pinholes that need to be maintained. Such methods are used by the CallTracker when REMOTE NATED endpoints initiate calls to ensure that their pinholes get maintained by NatMaintainer for the duration of the call.
Public Member Functions | |
| NatMaintainer (SipRouter *sipRouter) | |
| virtual | ~NatMaintainer () |
| virtual int | run (void *runArg) |
| Start running the NatMaintainer task. | |
| virtual void | requestShutdown (void) |
| Stop running the NatMaintainer task. | |
| void | addEndpointToKeepAlive (const TransportData &endpointToKeepAlive) |
| Add transport (protocol/address/port) to the list of endpoints to which we must send keepalives. | |
| void | removeEndpointToKeepAlive (const TransportData &endpointKeptAlive) |
| Remove transport from the list of endpoints. | |
Private Member Functions | |
| void | sendKeepAliveToContactList (UtlSList &contactList) |
| Send keepalives to the list of URIs (as UtlString's) in contactList. | |
| void | sendKeepAliveToExternalKeepAliveList (void) |
| Send keepalives to the endpoints in mExternalKeepAliveList. | |
| void | sendKeepAliveToEndpoint (const char *pIpAddress, uint16_t portNumber) |
| Send a keepalive to the specified address/port. (Transport is always UDP.). | |
Private Attributes | |
| uint32_t | mRefreshRoundNumber |
| Counter of refresh rounds. | |
| RegistrationDB * | mpRegistrationDB |
| The registration DB. | |
| SubscriptionDB * | mpSubscriptionDB |
| The subscription DB. | |
| int | mNextSeqValue |
| Sequence number to use in next OPTIONS wave. | |
| UtlString | mBaseCallId |
| Call-id from which all the others will be derived. | |
| OsMutex | mTimerMutex |
| Time-outs of mTimerMutex.acquire() provide the timing signal. | |
| SipRouter * | mpSipRouter |
| SipRouter through which to send keepalives. | |
| KeepAliveEndpointDescriptor * | mpEndpointsKeptAliveList |
| Array, indexed by endpoint listening port, of addresses and what keepalive round we last sent keepalives to them. | |
| SipMessage * | mpKeepAliveMessage |
| The keepalive message. List of TransportData's describing endpoints to which to send keepalives. | |
| UtlSList | mExternalKeepAliveList |
| OsMutex | mExternalKeepAliveListMutex |
| mutex protecting mExternalKeepAliveList | |
Classes | |
| struct | KeepAliveEndpointDescriptor |
| Information that NatMaintainer keeps about an endpoint. More... | |
| NatMaintainer | ( | SipRouter * | sipRouter | ) |
| ~NatMaintainer | ( | ) | [virtual] |
| int run | ( | void * | runArg | ) | [virtual] |
Start running the NatMaintainer task.
| void requestShutdown | ( | void | ) | [virtual] |
Stop running the NatMaintainer task.
| void addEndpointToKeepAlive | ( | const TransportData & | endpointToKeepAlive | ) |
Add transport (protocol/address/port) to the list of endpoints to which we must send keepalives.
| void removeEndpointToKeepAlive | ( | const TransportData & | endpointKeptAlive | ) |
Remove transport from the list of endpoints.
| void sendKeepAliveToContactList | ( | UtlSList & | contactList | ) | [private] |
Send keepalives to the list of URIs (as UtlString's) in contactList.
| void sendKeepAliveToExternalKeepAliveList | ( | void | ) | [private] |
Send keepalives to the endpoints in mExternalKeepAliveList.
| void sendKeepAliveToEndpoint | ( | const char * | pIpAddress, | |
| uint16_t | portNumber | |||
| ) | [private] |
Send a keepalive to the specified address/port. (Transport is always UDP.).
uint32_t mRefreshRoundNumber [private] |
Counter of refresh rounds.
RegistrationDB* mpRegistrationDB [private] |
The registration DB.
SubscriptionDB* mpSubscriptionDB [private] |
The subscription DB.
int mNextSeqValue [private] |
Sequence number to use in next OPTIONS wave.
UtlString mBaseCallId [private] |
Call-id from which all the others will be derived.
OsMutex mTimerMutex [private] |
Time-outs of mTimerMutex.acquire() provide the timing signal.
SipRouter* mpSipRouter [private] |
SipRouter through which to send keepalives.
Array, indexed by endpoint listening port, of addresses and what keepalive round we last sent keepalives to them.
SipMessage* mpKeepAliveMessage [private] |
The keepalive message. List of TransportData's describing endpoints to which to send keepalives.
UtlSList mExternalKeepAliveList [private] |
OsMutex mExternalKeepAliveListMutex [private] |
mutex protecting mExternalKeepAliveList