1/*
2 * PTP 1588 support
3 *
4 * This file implements a BPF that recognizes PTP event messages.
5 *
6 * Copyright (C) 2010 OMICRON electronics GmbH
7 *
8 *  This program is free software; you can redistribute it and/or modify
9 *  it under the terms of the GNU General Public License as published by
10 *  the Free Software Foundation; either version 2 of the License, or
11 *  (at your option) any later version.
12 *
13 *  This program is distributed in the hope that it will be useful,
14 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
15 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16 *  GNU General Public License for more details.
17 *
18 *  You should have received a copy of the GNU General Public License
19 *  along with this program; if not, write to the Free Software
20 *  Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21 */
22
23#ifndef _PTP_CLASSIFY_H_
24#define _PTP_CLASSIFY_H_
25
26#include <linux/ip.h>
27#include <linux/skbuff.h>
28
29#define PTP_CLASS_NONE  0x00 /* not a PTP event message */
30#define PTP_CLASS_V1    0x01 /* protocol version 1 */
31#define PTP_CLASS_V2    0x02 /* protocol version 2 */
32#define PTP_CLASS_VMASK 0x0f /* max protocol version is 15 */
33#define PTP_CLASS_IPV4  0x10 /* event in an IPV4 UDP packet */
34#define PTP_CLASS_IPV6  0x20 /* event in an IPV6 UDP packet */
35#define PTP_CLASS_L2    0x30 /* event in a L2 packet */
36#define PTP_CLASS_PMASK 0x30 /* mask for the packet type field */
37#define PTP_CLASS_VLAN  0x40 /* event in a VLAN tagged packet */
38
39#define PTP_CLASS_V1_IPV4 (PTP_CLASS_V1 | PTP_CLASS_IPV4)
40#define PTP_CLASS_V1_IPV6 (PTP_CLASS_V1 | PTP_CLASS_IPV6) /* probably DNE */
41#define PTP_CLASS_V2_IPV4 (PTP_CLASS_V2 | PTP_CLASS_IPV4)
42#define PTP_CLASS_V2_IPV6 (PTP_CLASS_V2 | PTP_CLASS_IPV6)
43#define PTP_CLASS_V2_L2   (PTP_CLASS_V2 | PTP_CLASS_L2)
44#define PTP_CLASS_V2_VLAN (PTP_CLASS_V2 | PTP_CLASS_VLAN)
45
46#define PTP_EV_PORT 319
47#define PTP_GEN_BIT 0x08 /* indicates general message, if set in message type */
48
49#define OFF_PTP_SOURCE_UUID	22 /* PTPv1 only */
50#define OFF_PTP_SEQUENCE_ID	30
51#define OFF_PTP_CONTROL		32 /* PTPv1 only */
52
53/* Below defines should actually be removed at some point in time. */
54#define IP6_HLEN	40
55#define UDP_HLEN	8
56#define OFF_IHL		14
57#define IPV4_HLEN(data) (((struct iphdr *)(data + OFF_IHL))->ihl << 2)
58
59#if defined(CONFIG_NET_PTP_CLASSIFY)
60/**
61 * ptp_classify_raw - classify a PTP packet
62 * @skb: buffer
63 *
64 * Runs a minimal BPF dissector to classify a network packet to
65 * determine the PTP class. In case the skb does not contain any
66 * PTP protocol data, PTP_CLASS_NONE will be returned, otherwise
67 * PTP_CLASS_V1_IPV{4,6}, PTP_CLASS_V2_IPV{4,6} or
68 * PTP_CLASS_V2_{L2,VLAN}, depending on the packet content.
69 */
70unsigned int ptp_classify_raw(const struct sk_buff *skb);
71
72void __init ptp_classifier_init(void);
73#else
74static inline void ptp_classifier_init(void)
75{
76}
77#endif
78#endif /* _PTP_CLASSIFY_H_ */
79