- allows registering and un-registering sent-by values
cc [ flag ... ] file ... -lsip [ library ... ] #include <sip.h> int sip_register_sent_by(char *val);
void sip_unregister_sent_by(char *val);
void sip_unregister_all_sent_by(int *error);
The sip_register_sent_by() function can be used to register a list of hostnames or IP addresses that the application may add to the VIA headers. The val is a comma separated list of such sent-by values. If any value is registered using sip_register_sent_by(), the SIP stack validates incoming responses to check if the sent-by parameter in the topmost VIA header is part of the registered list. If the check fails, the response is dropped. If there are no sent-by values registered, there is no check done on incoming responses.
The sip_unregister_sent_by() and sip_unregister_all_sent_by() functions are used to un-register sent-by values. The val for sip_unregister_sent_by() is a comma separated list of sent-by values that need to be un-registered. sip_unregister_all_sent_by() un-registers all the values that have been registered.
The sip_register_sent_by() function returns 0 on success and the appropriate error value on failure.
The value of errno is not changed by these calls in the event of an error.
See attributes(5) for descriptions of the following attributes: