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 0x40 /* event in a L2 packet */
36 #define PTP_CLASS_PMASK 0x70 /* mask for the packet type field */
37 #define PTP_CLASS_VLAN 0x80 /* 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 #define PTP_CLASS_L4 (PTP_CLASS_IPV4 | PTP_CLASS_IPV6)
46
47 #define PTP_EV_PORT 319
48 #define PTP_GEN_BIT 0x08 /* indicates general message, if set in message type */
49
50 #define OFF_PTP_SOURCE_UUID 22 /* PTPv1 only */
51 #define OFF_PTP_SEQUENCE_ID 30
52 #define OFF_PTP_CONTROL 32 /* PTPv1 only */
53
54 /* Below defines should actually be removed at some point in time. */
55 #define IP6_HLEN 40
56 #define UDP_HLEN 8
57 #define OFF_IHL 14
58 #define IPV4_HLEN(data) (((struct iphdr *)(data + OFF_IHL))->ihl << 2)
59
60 #if defined(CONFIG_NET_PTP_CLASSIFY)
61 /**
62 * ptp_classify_raw - classify a PTP packet
63 * @skb: buffer
64 *
65 * Runs a minimal BPF dissector to classify a network packet to
66 * determine the PTP class. In case the skb does not contain any
67 * PTP protocol data, PTP_CLASS_NONE will be returned, otherwise
68 * PTP_CLASS_V1_IPV{4,6}, PTP_CLASS_V2_IPV{4,6} or
69 * PTP_CLASS_V2_{L2,VLAN}, depending on the packet content.
70 */
71 unsigned int ptp_classify_raw(const struct sk_buff *skb);
72
73 void __init ptp_classifier_init(void);
74 #else
ptp_classifier_init(void)75 static inline void ptp_classifier_init(void)
76 {
77 }
ptp_classify_raw(struct sk_buff * skb)78 static inline unsigned int ptp_classify_raw(struct sk_buff *skb)
79 {
80 return PTP_CLASS_NONE;
81 }
82 #endif
83 #endif /* _PTP_CLASSIFY_H_ */
84