SipRouter Class Reference

#include <SipRouter.h>

Inheritance diagram for SipRouter:

List of all members.

---

Detailed Description

SipRouter implements the main message handling responsible for the forking authorization and forwarding of SIP messages.

The SipUserAgent sends a SipMessageEvent to the OsTask queue for this object; for each such message: -# Extract the SipMessage from the OsMsg passed by the SipUserAgent and call the proxyMessage method to process it

• proxyMessage does:
  1. Use SipMessage::normalizeProxyRoutes to get the route set into normal form, keeping a copy of any removed Route headers.
  2. Enforce Proxy-Require
  3. Check for and validate any user authentication in the message for this domain.
  4. Extract RouteState information (carried in Record-Route and Route headers) from the message.
  5. Invoke AuthPlugin::authorizeAndModify on the message for each configured AuthPlugin, stopping if any returns AuthPlugin::UNAUTHORIZED
     • An AuthPlugin may modify the message and/or the RouteState
  6. If all AuthPlugin objects return AuthPlugin::ALLOW_REQUEST, then proxyMessage returns true; if not, it sends a response before returning false:
     • '403 Forbidden' if there was valid user authentication in the message. (in this case, the reasonPhrase provided by AuthPlugin::authorizeAndModify is used if it is not null).
     • '407 Proxy Authentication Required' if there was no valid user authentication in the message.

If proxyMessage returned true, handleMessage passes it back to the SipUserAgent to be sent.

Most of the actual decision making is delegated to the AuthPlugin classes; see the AuthPlugin abstract base class for the interface and rules of operation. This allows modular extensions and changes to the authproxy operation without changing the basic proxy behavior.

Public Types
enum	ProxyAction {   SendRequest,   SendResponse,   DoNothing }
	Action to be taken by the caller of proxyAction method. More...
Public Member Functions
	SipRouter (SipUserAgent &sipUserAgent, ForwardRules &forwardingRules, OsConfigDb &configDb)
	Default constructor.
virtual	~SipRouter ()
virtual UtlBoolean	handleMessage (OsMsg &rMsg)
ProxyAction	proxyMessage (SipMessage &request, SipMessage &response)
	Examine a request to be proxied, and either modify it for forwarding or create a response.
bool	isLocalDomain (const Url &url, bool bIncludeDomainAliases=true) const
void	addHostAlias (const UtlString &hostAliasToAdd)
	Adds a new host alias to the list of aliases for proxy. This method is meant to be used by plugins that require special aliases.
void	addSipOutputProcessor (SipOutputProcessor *pProcessor)
UtlBoolean	removeSipOutputProcessor (SipOutputProcessor *pProcessor)
void	sendUdpKeepAlive (SipMessage &keepAliveMsg, const char *serverAddress, int port)
	Send a keepalive message to the specified address/port using the SipRouter's SipUserAgent.
void	getDomain (UtlString &canonicalDomain) const
	Get the canonical form of our SIP domain name.
const SharedSecret *	authSecret ()
	Get the domain shared secret for signing.
Private Member Functions
void	readConfig (OsConfigDb &configDb, const Url &defaultUri)
	Extract configuration parameters from the configuration file.
bool	isAuthenticated (const SipMessage &sipRequest, UtlString &authUser)
	Find the authenticated identity for a request (if any).
bool	addPathHeaderIfNATRegisterRequest (SipMessage &sipRequest) const
	If sipRequest is a REGISTER that came from behind a NAT (indicated by 'received' parameter on topmost Via), add an initial signed Path URI for this proxy.
bool	addNatMappingInfoToContacts (SipMessage &sipRequest) const
bool	areAllExtensionsSupported (const SipMessage &sipRequest, UtlString &disallowedExtensions) const
	Verifies if the proxy supports all the extensions listed in the Proxy-Require header of an incoming request.
void	authenticationChallenge (const SipMessage &sipRequest, SipMessage &challenge)
	Create an authentication challenge.
bool	isPAIdentityApplicable (const SipMessage &sipRequest)
	P-Asserted-Identity header is only applicable for INVITE, REFER, BYE, OPTIONS, NOTIFY, and SUBSCRIBE.
Private Attributes
SipUserAgent *	mpSipUserAgent
	SIP stack interface.
bool	mAuthenticationEnabled
	based on SIPX_PROXY_AUTHENTICATE_ALGORITHM
UtlString	mRealm
	realm for challenges - common to replicatants
SipNonceDb	mNonceDb
	generator for nonce values
long	mNonceExpiration
	nonce lifetime in seconds
UtlString	mDomainName
	for determining authority for addresses
UtlString	mDomainAliases
	for determining authority for addresses
UtlString	mRouteHostPort
	for writing Record-Route headers
SharedSecret *	mSharedSecret
	secret value to include in authentication hashes
ForwardRules *	mpForwardingRules
	Holds to forwarding rules instructions.
PluginHooks	mAuthPlugins
	decision making modules from configuration
Friends
class	SipRouterTest

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Member Enumeration Documentation

enum ProxyAction

Action to be taken by the caller of proxyAction method.

Enumerator:

SendRequest
SendResponse
DoNothing

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Constructor & Destructor Documentation

SipRouter	(	SipUserAgent &	sipUserAgent,
		ForwardRules &	forwardingRules,
		OsConfigDb &	configDb
	)

Default constructor.

~SipRouter

(

)

[virtual]

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Member Function Documentation

UtlBoolean handleMessage

(

OsMsg &

rMsg

)

[virtual]

Reimplemented from OsServerTask.

SipRouter::ProxyAction proxyMessage	(	SipMessage &	request,
		SipMessage &	response
	)

Examine a request to be proxied, and either modify it for forwarding or create a response.

the caller must pass either request or response to SipUserAgent::send as directed by the return code

Parameters:

request	request to be proxied iff return is SendRequest
response	response to be sent iff return is SendResponse

bool isLocalDomain	(	const Url &	url,
		bool	bIncludeDomainAliases = true
	)			const

Returns:

true iff the domain of url is a valid form of the domain name for this proxy.

Parameters:

url	a url to be tested
bIncludeDomainAliases	also test for domain alias matches

void addHostAlias

(

const UtlString &

hostAliasToAdd

)

Adds a new host alias to the list of aliases for proxy. This method is meant to be used by plugins that require special aliases.

void addSipOutputProcessor

(

SipOutputProcessor *

pProcessor

)

UtlBoolean removeSipOutputProcessor

(

SipOutputProcessor *

pProcessor

)

void sendUdpKeepAlive	(	SipMessage &	keepAliveMsg,
		const char *	serverAddress,
		int	port
	)

Send a keepalive message to the specified address/port using the SipRouter's SipUserAgent.

void getDomain

(

UtlString &

canonicalDomain

)

const

Get the canonical form of our SIP domain name.

const SharedSecret* authSecret

(

)

Get the domain shared secret for signing.

void readConfig	(	OsConfigDb &	configDb,
		const Url &	defaultUri
	)			[private]

Extract configuration parameters from the configuration file.

Parameters:

defaultUri

database to read for parameters to be used for default realm and route

bool isAuthenticated	(	const SipMessage &	sipRequest,
		UtlString &	authUser
	)			[private]

Find the authenticated identity for a request (if any).

Check the credentials in sipRequest for valid credentials for a user in mRealm.

Returns:

true iff valid authentication is found (and sets authUser).

Parameters:

sipRequest	message to be checked for authentication
authUser	returned authenticated identity uri

bool addPathHeaderIfNATRegisterRequest

(

SipMessage &

sipRequest

)

const [private]

If sipRequest is a REGISTER that came from behind a NAT (indicated by 'received' parameter on topmost Via), add an initial signed Path URI for this proxy.

Returns:

true iff sipRequest was modified.

bool addNatMappingInfoToContacts

(

SipMessage &

sipRequest

)

const [private]

bool areAllExtensionsSupported	(	const SipMessage &	sipRequest,
		UtlString &	disallowedExtensions
	)			const [private]

Verifies if the proxy supports all the extensions listed in the Proxy-Require header of an incoming request.

Parameters:

sipRequest	request to be evluated
disallowedExtensions	unsupported extensions

void authenticationChallenge	(	const SipMessage &	sipRequest,
		SipMessage &	challenge
	)			[private]

Create an authentication challenge.

Parameters:

sipRequest	message to be challenged.
challenge	challenge response.

bool isPAIdentityApplicable

(

const SipMessage &

sipRequest

)

[private]

P-Asserted-Identity header is only applicable for INVITE, REFER, BYE, OPTIONS, NOTIFY, and SUBSCRIBE.

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Friends And Related Function Documentation

friend class SipRouterTest [friend]

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Member Data Documentation

SipUserAgent* mpSipUserAgent [private]

SIP stack interface.

bool mAuthenticationEnabled [private]

based on SIPX_PROXY_AUTHENTICATE_ALGORITHM

UtlString mRealm [private]

realm for challenges - common to replicatants

SipNonceDb mNonceDb [private]

generator for nonce values

long mNonceExpiration [private]

nonce lifetime in seconds

UtlString mDomainName [private]

for determining authority for addresses

UtlString mDomainAliases [private]

for determining authority for addresses

UtlString mRouteHostPort [private]

for writing Record-Route headers

SharedSecret* mSharedSecret [private]

secret value to include in authentication hashes

ForwardRules* mpForwardingRules [private]

Holds to forwarding rules instructions.

PluginHooks mAuthPlugins [private]

decision making modules from configuration