quic: pass the connection ID length into 1-RTT packet parsing
1-RTT packets contain a variable-length connection ID field, but
no indication of the length of the connection ID. The recipient
of the packet has chosen the connection ID, and is expected to
either choose a consistent length or encode the length in the
connection ID.
Change the parse1RTTPacket function to take the connection ID
length as an input, rather than assuming that all 1-RTT packets
contain our hardcoded connection ID length.
This permits using parse1RTTPacket in tests which may create
and parse packets using other lengths.
For golang/go#58547
Change-Id: I9d09e4a0041051be1604c9146f6db9ca959ad696
Reviewed-on: https://go-review.googlesource.com/c/net/+/504856
Run-TryBot: Damien Neil <dneil@google.com>
Reviewed-by: Jonathan Amsterdam <jba@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
diff --git a/internal/quic/packet_codec_test.go b/internal/quic/packet_codec_test.go
index 499ec4d..3503d24 100644
--- a/internal/quic/packet_codec_test.go
+++ b/internal/quic/packet_codec_test.go
@@ -185,7 +185,7 @@
w.b = append(w.b, test.payload...)
w.finish1RTTPacket(test.num, 0, connID, test.k)
pkt := w.datagram()
- p, n := parse1RTTPacket(pkt, test.k, 0)
+ p, n := parse1RTTPacket(pkt, test.k, connIDLen, 0)
if n != len(pkt) {
t.Errorf("parse1RTTPacket: n=%v, want %v", n, len(pkt))
}
diff --git a/internal/quic/packet_parser.go b/internal/quic/packet_parser.go
index e910e0e..908a82e 100644
--- a/internal/quic/packet_parser.go
+++ b/internal/quic/packet_parser.go
@@ -146,9 +146,9 @@
//
// On input, pkt contains a short header packet, k the decryption keys for the packet,
// and pnumMax the largest packet number seen in the number space of this packet.
-func parse1RTTPacket(pkt []byte, k keys, pnumMax packetNumber) (p shortPacket, n int) {
+func parse1RTTPacket(pkt []byte, k keys, dstConnIDLen int, pnumMax packetNumber) (p shortPacket, n int) {
var err error
- p.payload, p.num, err = k.unprotect(pkt, 1+connIDLen, pnumMax)
+ p.payload, p.num, err = k.unprotect(pkt, 1+dstConnIDLen, pnumMax)
if err != nil {
return shortPacket{}, -1
}
