BUG/MINOR: quic: Do not drop too small datagrams with Initial packets

When receiving an Initial packet a peer must drop it if the datagram is smaller
than 1200. Before this patch, this is the entire datagram which was dropped.

In such a case, drop the packet after having parsed its length.

Must be backported to 2.6 and 2.7

(cherry picked from commit 35218c6357b441142b2af19e31c8991a28b97075)
Signed-off-by: Christopher Faulet <cfaulet@haproxy.com>
(cherry picked from commit 97c8d5767f9f2e4b07f52bf2cbd3a3ba32d4e839)
Signed-off-by: Amaury Denoyelle <adenoyelle@haproxy.com>
This commit is contained in:
Frédéric Lécaille 2023-02-16 11:40:11 +01:00 committed by Amaury Denoyelle
parent 29165bffcc
commit 2b3722942c

View File

@ -6211,13 +6211,6 @@ static int quic_rx_pkt_parse(struct quic_rx_packet *pkt,
goto drop;
}
if (pkt->type == QUIC_PACKET_TYPE_INITIAL &&
dgram->len < QUIC_INITIAL_PACKET_MINLEN) {
TRACE_PROTO("Too short datagram with an Initial packet", QUIC_EV_CONN_LPKT);
HA_ATOMIC_INC(&prx_counters->too_short_initial_dgram);
goto drop;
}
/* When multiple QUIC packets are coalesced on the same UDP datagram,
* they must have the same DCID.
*/
@ -6312,6 +6305,19 @@ static int quic_rx_pkt_parse(struct quic_rx_packet *pkt,
pkt->pn_offset = buf - beg;
pkt->len = pkt->pn_offset + len;
/* RFC 9000. Initial Datagram Size
*
* A server MUST discard an Initial packet that is carried in a UDP datagram
* with a payload that is smaller than the smallest allowed maximum datagram
* size of 1200 bytes.
*/
if (pkt->type == QUIC_PACKET_TYPE_INITIAL &&
dgram->len < QUIC_INITIAL_PACKET_MINLEN) {
TRACE_PROTO("Too short datagram with an Initial packet", QUIC_EV_CONN_LPKT);
HA_ATOMIC_INC(&prx_counters->too_short_initial_dgram);
goto drop;
}
/* Interrupt parsing after packet length retrieval : this
* ensures that only the packet is dropped but not the whole
* datagram.