This changes the implementations for the reception of RESET and
RESET_ACK to be compatible with 3GPP TS 08.16, 7.3.1:
- Just send a RESET_ACK with correct values back to the SGSN when a
RESET with an invalid NSVCI or NSEI has been received.
- Check RESET_ACK for matching NSEI and NSVCI.
- Ignore unexpected RESET_ACKs.
In addition, use RESET_ACK from a BSS to update the BSS source
address based on the NSVCI to be tolerant with changing UDP source
addresses/ports.
Sponsored-by: On-Waves ehf
Under special circumstances (see below) receiving a NS-RESET leads to
duplicated NS-VC entries.
This happens when the source port of a NS-VC changes to a new one
that has already been used by another NS-VC.
This patch changes gprs_ns_rx_reset() to check for this case and to
use the existing NS-VC object. The NS-VC object that was associated
with the source address before is detached from this source but kept
in the NS-VC list so that it can be reattached when a correspondent
NS-RESET is received later on. Meanwhile it will have a cleared link
layer address which will not match a real link info.
A new counter NS_CTR_REPLACED is incremented each time when the NS-VC
object is replacing another one. A new signal S_NS_REPLACED is added
which gets dispatched in this case, too.
Another new counter NS_CTR_NSEI_CHG is incremented each time when the
NSEI of a NS-VC object (with fixed NSVCI) changes.
Ticket: OW#874
Sponsored-by: On-Waves ehf
Adds the functions gprs_ns_ll_copy() and gprs_ns_ll_clear(). Renames
gprs_ns_format_peer() to gprs_ns_ll_str(). All of these functions
uniformly access the link layer part within the NS-VC objects.
Sponsored-by: On-Waves ehf
Register an osmo signal handler to print a short notice about every
SS_L_NS signal that is generated while processing the tests.
Sponsored-by: On-Waves ehf
This patch refactors gprs_ns_rcvmsg() by moving the parts relevant to
the NS messages into the new functions gprs_ns_vc_create() (nsvc
object creation) and gprs_ns_process_msg() (main NS automaton). These
do not contain code that directly depends on the link layer (they
call other functions that still do). This reduces the gprs_ns_rcvmsg()
function to calling these two functions and optionally setting up the
link layer specific fields of the nsvc.
Sponsored-by: On-Waves ehf
Sylvain Munaut
Jacob Erlbeck
Harald Welte