MINOR: quic: Parse long packet version from qc_parse_hd_form()

This is to prepare the support for QUIC v2 version. The packet type
depends on the version. So, we must parse early enough the version
before defining the type of each packet.
diff --git a/src/xprt_quic.c b/src/xprt_quic.c
index 145cf00..a899ec7 100644
--- a/src/xprt_quic.c
+++ b/src/xprt_quic.c
@@ -4537,8 +4537,7 @@
 {
 	unsigned char dcid_len, scid_len;
 
-	/* Version */
-	if (!quic_read_uint32(&pkt->version, (const unsigned char **)buf, end))
+	if (end == *buf)
 		return 0;
 
 	/* Destination Connection ID Length */
@@ -4662,21 +4661,51 @@
 	return 0;
 }
 
-/* Parse the header form from <byte0> first byte of <pkt> pacekt to set type.
+/* Parse the header form from <byte0> first byte of <pkt> packet to set its type.
  * Also set <*long_header> to 1 if this form is long, 0 if not.
  */
-static inline void qc_parse_hd_form(struct quic_rx_packet *pkt,
-                                    unsigned char byte0, int *long_header)
+static inline int qc_parse_hd_form(struct quic_rx_packet *pkt,
+                                   unsigned char **buf, const unsigned char *end,
+                                   int *long_header)
 {
+	const unsigned char byte0 = **buf;
+
+	(*buf)++;
 	if (byte0 & QUIC_PACKET_LONG_HEADER_BIT) {
-		pkt->type =
+		unsigned char type =
 			(byte0 >> QUIC_PACKET_TYPE_SHIFT) & QUIC_PACKET_TYPE_BITMASK;
+
 		*long_header = 1;
+		/* Version */
+		if (!quic_read_uint32(&pkt->version, (const unsigned char **)buf, end))
+			return 0;
+
+		if (pkt->version != QUIC_PROTOCOL_VERSION_2_DRAFT) {
+			pkt->type = type;
+		}
+		else {
+			switch (type) {
+			case 0:
+				pkt->type = QUIC_PACKET_TYPE_RETRY;
+				break;
+			case 1:
+				pkt->type = QUIC_PACKET_TYPE_INITIAL;
+				break;
+			case 2:
+				pkt->type = QUIC_PACKET_TYPE_0RTT;
+				break;
+			case 3:
+				pkt->type = QUIC_PACKET_TYPE_HANDSHAKE;
+				break;
+			}
+		}
 	}
 	else {
 		pkt->type = QUIC_PACKET_TYPE_SHORT;
 		*long_header = 0;
 	}
+
+	return 1;
 }
 
 /*
@@ -5242,7 +5271,11 @@
 	}
 
 	/* Header form */
-	qc_parse_hd_form(pkt, *buf++, &long_header);
+	if (!qc_parse_hd_form(pkt, &buf, end, &long_header)) {
+		TRACE_PROTO("Packet dropped", QUIC_EV_CONN_LPKT);
+		goto drop;
+	}
+
 	if (long_header) {
 		uint64_t len;
 		struct quic_cid odcid;