dp83640: Include hash in timestamp/packet matching

Only using the message type and sequence id for matching timestamps
with packets is error prone, as multiple clients may very well be
sending packets with the same messagetype and timestamp at the same
time. Fix by extending the check to include the hash of bytes 20-29
(source id in PTPv2) that is provided with the timestamps.

Signed-off-by: Stefan Sørensen <stefan.sorensen@spectralink.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
This commit is contained in:
Stefan Sørensen 2015-11-03 09:34:04 +01:00 committed by David S. Miller
parent 0561e8e878
commit 539e44d268

View File

@ -20,6 +20,7 @@
#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt
#include <linux/crc32.h>
#include <linux/ethtool.h> #include <linux/ethtool.h>
#include <linux/kernel.h> #include <linux/kernel.h>
#include <linux/list.h> #include <linux/list.h>
@ -787,9 +788,12 @@ static int decode_evnt(struct dp83640_private *dp83640,
return parsed; return parsed;
} }
#define DP83640_PACKET_HASH_OFFSET 20
#define DP83640_PACKET_HASH_LEN 10
static int match(struct sk_buff *skb, unsigned int type, struct rxts *rxts) static int match(struct sk_buff *skb, unsigned int type, struct rxts *rxts)
{ {
u16 *seqid; u16 *seqid, hash;
unsigned int offset = 0; unsigned int offset = 0;
u8 *msgtype, *data = skb_mac_header(skb); u8 *msgtype, *data = skb_mac_header(skb);
@ -819,11 +823,19 @@ static int match(struct sk_buff *skb, unsigned int type, struct rxts *rxts)
msgtype = data + offset + OFF_PTP_CONTROL; msgtype = data + offset + OFF_PTP_CONTROL;
else else
msgtype = data + offset; msgtype = data + offset;
if (rxts->msgtype != (*msgtype & 0xf))
return 0;
seqid = (u16 *)(data + offset + OFF_PTP_SEQUENCE_ID); seqid = (u16 *)(data + offset + OFF_PTP_SEQUENCE_ID);
if (rxts->seqid != ntohs(*seqid))
return 0;
return rxts->msgtype == (*msgtype & 0xf) && hash = ether_crc(DP83640_PACKET_HASH_LEN,
rxts->seqid == ntohs(*seqid); data + offset + DP83640_PACKET_HASH_OFFSET) >> 20;
if (rxts->hash != hash)
return 0;
return 1;
} }
static void decode_rxts(struct dp83640_private *dp83640, static void decode_rxts(struct dp83640_private *dp83640,