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 struct clock_identity { 48 u8 id[8]; 49 } __packed; 50 51 struct port_identity { 52 struct clock_identity clock_identity; 53 __be16 port_number; 54 } __packed; 55 56 struct ptp_header { 57 u8 tsmt; /* transportSpecific | messageType */ 58 u8 ver; /* reserved | versionPTP */ 59 __be16 message_length; 60 u8 domain_number; 61 u8 reserved1; 62 u8 flag_field[2]; 63 __be64 correction; 64 __be32 reserved2; 65 struct port_identity source_port_identity; 66 __be16 sequence_id; 67 u8 control; 68 u8 log_message_interval; 69 } __packed; 70 71 #if defined(CONFIG_NET_PTP_CLASSIFY) 72 /** 73 * ptp_classify_raw - classify a PTP packet 74 * @skb: buffer 75 * 76 * Runs a minimal BPF dissector to classify a network packet to 77 * determine the PTP class. In case the skb does not contain any 78 * PTP protocol data, PTP_CLASS_NONE will be returned, otherwise 79 * PTP_CLASS_V1_IPV{4,6}, PTP_CLASS_V2_IPV{4,6} or 80 * PTP_CLASS_V2_{L2,VLAN}, depending on the packet content. 81 */ 82 unsigned int ptp_classify_raw(const struct sk_buff *skb); 83 84 /** 85 * ptp_parse_header - Get pointer to the PTP v2 header 86 * @skb: packet buffer 87 * @type: type of the packet (see ptp_classify_raw()) 88 * 89 * This function takes care of the VLAN, UDP, IPv4 and IPv6 headers. The length 90 * is checked. 91 * 92 * Note, internally skb_mac_header() is used. Make sure that the @skb is 93 * initialized accordingly. 94 * 95 * Return: Pointer to the ptp v2 header or NULL if not found 96 */ 97 struct ptp_header *ptp_parse_header(struct sk_buff *skb, unsigned int type); 98 99 void __init ptp_classifier_init(void); 100 #else 101 static inline void ptp_classifier_init(void) 102 { 103 } 104 static inline unsigned int ptp_classify_raw(struct sk_buff *skb) 105 { 106 return PTP_CLASS_NONE; 107 } 108 static inline struct ptp_header *ptp_parse_header(struct sk_buff *skb, 109 unsigned int type) 110 { 111 return NULL; 112 } 113 #endif 114 #endif /* _PTP_CLASSIFY_H_ */ 115