tnt has uploaded this change for review. ( https://gerrit.osmocom.org/c/osmo-e1d/+/27826 )
Change subject: OCTOI: Fix the extension of 16b FN from packet to full 32b FN ......................................................................
OCTOI: Fix the extension of 16b FN from packet to full 32b FN
Only frames withing a certain window are even accepted for processing the rest is dropped since it could corrupt our state.
Signed-off-by: Sylvain Munaut tnt@246tNt.com Change-Id: I25b2e150d924aa8c714b766cb92e9e23e67cfa4c --- M src/octoi/e1oip.c 1 file changed, 19 insertions(+), 25 deletions(-)
git pull ssh://gerrit.osmocom.org:29418/osmo-e1d refs/changes/26/27826/1
diff --git a/src/octoi/e1oip.c b/src/octoi/e1oip.c index 27eb201..482b89c 100644 --- a/src/octoi/e1oip.c +++ b/src/octoi/e1oip.c @@ -165,10 +165,12 @@ /* An E1OIP_MSGT_TDM_DATA message was received from a remote IP peer */ int e1oip_rcvmsg_tdm_data(struct e1oip_line *iline, struct msgb *msg) { + const int WIN = 8000; struct octoi_peer *peer = iline->peer; const struct e1oip_tdm_hdr *e1th; uint16_t frame_nr; uint32_t fn32; + bool update_next; uint32_t ts_mask; uint8_t idx2ts[BYTES_PER_FRAME]; unsigned int n_frames; @@ -194,32 +196,25 @@ ts_mask = ntohl(e1th->ts_mask);
if (frame_nr != exp_next_seq) { - int delta = frame_nr - exp_next_seq; - bool re_ordering; - if (delta > 0 && delta < 5 * iline->cfg.batching_factor) { - /* assume re-ordering */ - re_ordering = true; - } else { - /* assume packet loss */ - re_ordering = false; + uint16_t frame_nr_ofs; + + LOGPEER(peer, LOGL_NOTICE, "RxIP: frame_nr=%u, but expected %u\n", + frame_nr, exp_next_seq); + + frame_nr_ofs = frame_nr - (exp_next_seq - WIN); + if (frame_nr_ofs > (2 * WIN)) { + /* Outside window, throw packet away */ + LOGPEER(peer, LOGL_NOTICE, "RxIP: frame_nr=%u at exp_next_fn32=%u; " + "received frame outside +/- 1s window of expected frame\n", + frame_nr, iline->e1t.next_fn32); + return -EINVAL; }
- LOGPEER(peer, LOGL_NOTICE, "RxIP: frame_nr=%u, but expected %u: delta=%d - assuming %s\n", - frame_nr, exp_next_seq, delta, re_ordering ? "re-ordering" : "packet loss"); - - fn32 = (iline->e1t.next_fn32 & 0xffff0000) + frame_nr; - if (fn32 > iline->e1t.next_fn32 + 8000) { - /* more than 1s in the future: was this a wrap-around? */ - fn32 = ((iline->e1t.next_fn32 & 0xffff0000) - 0x10000) + frame_nr; - if (fn32 < iline->e1t.next_fn32 - 8000) { - /* also no match: give up */ - LOGPEER(peer, LOGL_NOTICE, "RxIP: frame_nr=%u at exp_next_fn32=%u; " - "received frame outside +/- 1s window of expected frame\n", - frame_nr, iline->e1t.next_fn32); - } - } + fn32 = iline->e1t.next_fn32 + frame_nr_ofs - WIN; + update_next = frame_nr_ofs >= WIN; } else { fn32 = iline->e1t.next_fn32; + update_next = true; }
/* compute E1oIP idx to timeslot table */ @@ -252,9 +247,8 @@ } /* update local state */ memcpy(iline->e1t.last_frame, frame_buf, BYTES_PER_FRAME); - /* FIXME: only in some cases */ - //if (fn32 >= iline->e1t.next_fn32I - iline->e1t.next_fn32 = fn32 + n_frames; + if (update_next) + iline->e1t.next_fn32 = fn32 + n_frames;
iline_stat_set(iline, LINE_STAT_E1oIP_E1T_FIFO, frame_rifo_depth(&iline->e1t.rifo));