ROHC library mishandles RTP Payload Type (PT) changes

Confirmed for 1.2.1.

Confirmed for 1.3.0.

Confirmed for trunk.

Fix committed in branch 1.2.x, see http://bazaar.launchpad.net/~didier-barvaux/rohc/1.2.x/revision/113. Scheduled for release 1.2.2.

The change on the RTP Payload Type (PT) field was not detected correctly because the function is_changed() that reports if a field changed in the IP/UDP/RTP headers returned a bitmask instead of a boolean. The bitmask was later truncated in a 8-bit variable and the fact that the Payload Type changed was lost. The Payload Type was the only field impacted since it was the only one that got a value greater than 0xFF in the bitmask.

The detection of a change in the RTP Payload Type (PT) field was moved in the rtp_changed_rtp_dynamic() function of the c_rtp.c file because the code is specific to the RTP profile.

As a side effect, a bug that affected the extension 3 of the UOR-2 packets was found. The decision to set the "I" flag to 1 and the decison to put the optional IP-ID field were not the same. This leads to ROHC packets with the "I" flag set but without the related IP-ID field or ROHC packets without the "I" flag set but with the related IP-ID field.

This bug was fixed on the 1.2.x branch because it does not affects the compatibility with previous 1.2.x releases.

The capture that is attached to the bug was used to create a new non-regression test.

Fix committed in branch 1.3.x, see http://bazaar.launchpad.net/~didier-barvaux/rohc/1.3.x/revision/137. Scheduled for release 1.2.2.

The fix is the same as the one for branch 1.2.x. The new non-regression test was adapted to be run within "make check".

The bug was fixed on the 1.3.x branch because it does not affects the compatibility with previous 1.3.x releases.

Errata: the fix committed in branch 1.3.x is scheduled for release 1.3.1 not 1.2.2.

Fix committed in trunk, see http://bazaar.launchpad.net/~didier-barvaux/rohc/main/revision/142. Scheduled for release 1.4.0.

The fix is the same as the one for branch 1.3.x. Some debug traces that helped a lot during bug analysis and fix were also committed.

Fix released in version 1.3.1.

Fix released in version 1.2.2.