lib: Skip DRF rebase on same-epoch retransmit

On some stalls the receiver can go inactive and NACK-driven HoL
retransmits and brief snd-window drains can deliver a DRF-flagged
packet that's still part of the current receive epoch (rxm_pkt_prepare
preserves the original flags). This treats in-window DRF and
RXM-flagged DRF arrivals as same-epoch once the window is seeded and
skip the release_rq + lwe/rwe rebase that would otherwise wipe valid
OOO fragments from rq[].

Bootstrap (lwe == rwe) still rebases unconditionally so a NACK-driven
retransmit of a lost initial DRF can seed the receiver.

Harden seqno_rotate to redraw the ISN until it falls outside the
peer's current rcv window, closing the ~RQ_SIZE / 2^32 collision where
a true new epoch would be misclassified as same-epoch.

Signed-off-by: Dimitri Staessens <dimitri@ouroboros.rocks>
Signed-off-by: Sander Vrijders <sander@ouroboros.rocks>

0 files changed, 0 insertions, 0 deletions