1 /* SPDX-License-Identifier: GPL-2.0-or-later */
2 /*
3  * PTP 1588 support
4  *
5  * This file implements a BPF that recognizes PTP event messages.
6  *
7  * Copyright (C) 2010 OMICRON electronics GmbH
8  */
9 
10 #ifndef _PTP_CLASSIFY_H_
11 #define _PTP_CLASSIFY_H_
12 
13 #include <linux/ip.h>
14 #include <linux/skbuff.h>
15 
16 #define PTP_CLASS_NONE  0x00 /* not a PTP event message */
17 #define PTP_CLASS_V1    0x01 /* protocol version 1 */
18 #define PTP_CLASS_V2    0x02 /* protocol version 2 */
19 #define PTP_CLASS_VMASK 0x0f /* max protocol version is 15 */
20 #define PTP_CLASS_IPV4  0x10 /* event in an IPV4 UDP packet */
21 #define PTP_CLASS_IPV6  0x20 /* event in an IPV6 UDP packet */
22 #define PTP_CLASS_L2    0x40 /* event in a L2 packet */
23 #define PTP_CLASS_PMASK	0x70 /* mask for the packet type field */
24 #define PTP_CLASS_VLAN	0x80 /* event in a VLAN tagged packet */
25 
26 #define PTP_CLASS_V1_IPV4 (PTP_CLASS_V1 | PTP_CLASS_IPV4)
27 #define PTP_CLASS_V1_IPV6 (PTP_CLASS_V1 | PTP_CLASS_IPV6) /* probably DNE */
28 #define PTP_CLASS_V2_IPV4 (PTP_CLASS_V2 | PTP_CLASS_IPV4)
29 #define PTP_CLASS_V2_IPV6 (PTP_CLASS_V2 | PTP_CLASS_IPV6)
30 #define PTP_CLASS_V2_L2   (PTP_CLASS_V2 | PTP_CLASS_L2)
31 #define PTP_CLASS_V2_VLAN (PTP_CLASS_V2 | PTP_CLASS_VLAN)
32 #define PTP_CLASS_L4      (PTP_CLASS_IPV4 | PTP_CLASS_IPV6)
33 
34 #define PTP_EV_PORT 319
35 #define PTP_GEN_BIT 0x08 /* indicates general message, if set in message type */
36 
37 #define OFF_PTP_SOURCE_UUID	22 /* PTPv1 only */
38 #define OFF_PTP_SEQUENCE_ID	30
39 #define OFF_PTP_CONTROL		32 /* PTPv1 only */
40 
41 /* Below defines should actually be removed at some point in time. */
42 #define IP6_HLEN	40
43 #define UDP_HLEN	8
44 #define OFF_IHL		14
45 #define IPV4_HLEN(data) (((struct iphdr *)(data + OFF_IHL))->ihl << 2)
46 
47 #if defined(CONFIG_NET_PTP_CLASSIFY)
48 /**
49  * ptp_classify_raw - classify a PTP packet
50  * @skb: buffer
51  *
52  * Runs a minimal BPF dissector to classify a network packet to
53  * determine the PTP class. In case the skb does not contain any
54  * PTP protocol data, PTP_CLASS_NONE will be returned, otherwise
55  * PTP_CLASS_V1_IPV{4,6}, PTP_CLASS_V2_IPV{4,6} or
56  * PTP_CLASS_V2_{L2,VLAN}, depending on the packet content.
57  */
58 unsigned int ptp_classify_raw(const struct sk_buff *skb);
59 
60 void __init ptp_classifier_init(void);
61 #else
ptp_classifier_init(void)62 static inline void ptp_classifier_init(void)
63 {
64 }
ptp_classify_raw(struct sk_buff * skb)65 static inline unsigned int ptp_classify_raw(struct sk_buff *skb)
66 {
67 	return PTP_CLASS_NONE;
68 }
69 #endif
70 #endif /* _PTP_CLASSIFY_H_ */
71