/* SPDX-License-Identifier: GPL-2.0-or-later */ /* * PTP 1588 support * * This file implements a BPF that recognizes PTP event messages. * * Copyright (C) 2010 OMICRON electronics GmbH */ #ifndef _PTP_CLASSIFY_H_ #define _PTP_CLASSIFY_H_ #include <linux/ip.h> #include <linux/skbuff.h> #define PTP_CLASS_NONE 0x00 /* not a PTP event message */ #define PTP_CLASS_V1 0x01 /* protocol version 1 */ #define PTP_CLASS_V2 0x02 /* protocol version 2 */ #define PTP_CLASS_VMASK 0x0f /* max protocol version is 15 */ #define PTP_CLASS_IPV4 0x10 /* event in an IPV4 UDP packet */ #define PTP_CLASS_IPV6 0x20 /* event in an IPV6 UDP packet */ #define PTP_CLASS_L2 0x40 /* event in a L2 packet */ #define PTP_CLASS_PMASK 0x70 /* mask for the packet type field */ #define PTP_CLASS_VLAN 0x80 /* event in a VLAN tagged packet */ #define PTP_CLASS_V1_IPV4 (PTP_CLASS_V1 | PTP_CLASS_IPV4) #define PTP_CLASS_V1_IPV6 (PTP_CLASS_V1 | PTP_CLASS_IPV6) /* probably DNE */ #define PTP_CLASS_V2_IPV4 (PTP_CLASS_V2 | PTP_CLASS_IPV4) #define PTP_CLASS_V2_IPV6 (PTP_CLASS_V2 | PTP_CLASS_IPV6) #define PTP_CLASS_V2_L2 (PTP_CLASS_V2 | PTP_CLASS_L2) #define PTP_CLASS_V2_VLAN (PTP_CLASS_V2 | PTP_CLASS_VLAN) #define PTP_CLASS_L4 (PTP_CLASS_IPV4 | PTP_CLASS_IPV6) #define PTP_MSGTYPE_SYNC 0x0 #define PTP_MSGTYPE_DELAY_REQ 0x1 #define PTP_MSGTYPE_PDELAY_REQ 0x2 #define PTP_MSGTYPE_PDELAY_RESP 0x3 #define PTP_EV_PORT 319 #define PTP_GEN_BIT 0x08 /* indicates general message, if set in message type */ #define OFF_PTP_SOURCE_UUID 22 /* PTPv1 only */ #define OFF_PTP_SEQUENCE_ID 30 /* Below defines should actually be removed at some point in time. */ #define IP6_HLEN 40 #define UDP_HLEN 8 #define OFF_IHL 14 #define IPV4_HLEN(data) (((struct iphdr *)(data + OFF_IHL))->ihl << 2) struct clock_identity { u8 id[8]; } __packed; struct port_identity { struct clock_identity clock_identity; __be16 port_number; } __packed; struct ptp_header { u8 tsmt; /* transportSpecific | messageType */ u8 ver; /* reserved | versionPTP */ __be16 message_length; u8 domain_number; u8 reserved1; u8 flag_field[2]; __be64 correction; __be32 reserved2; struct port_identity source_port_identity; __be16 sequence_id; u8 control; u8 log_message_interval; } __packed; #if defined(CONFIG_NET_PTP_CLASSIFY) /** * ptp_classify_raw - classify a PTP packet * @skb: buffer * * Runs a minimal BPF dissector to classify a network packet to * determine the PTP class. In case the skb does not contain any * PTP protocol data, PTP_CLASS_NONE will be returned, otherwise * PTP_CLASS_V1_IPV{4,6}, PTP_CLASS_V2_IPV{4,6} or * PTP_CLASS_V2_{L2,VLAN}, depending on the packet content. */ unsigned int ptp_classify_raw(const struct sk_buff *skb); /** * ptp_parse_header - Get pointer to the PTP v2 header * @skb: packet buffer * @type: type of the packet (see ptp_classify_raw()) * * This function takes care of the VLAN, UDP, IPv4 and IPv6 headers. The length * is checked. * * Note, internally skb_mac_header() is used. Make sure that the @skb is * initialized accordingly. * * Return: Pointer to the ptp v2 header or NULL if not found */ struct ptp_header *ptp_parse_header(struct sk_buff *skb, unsigned int type); /** * ptp_get_msgtype - Extract ptp message type from given header * @hdr: ptp header * @type: type of the packet (see ptp_classify_raw()) * * This function returns the message type for a given ptp header. It takes care * of the different ptp header versions (v1 or v2). * * Return: The message type */ static inline u8 ptp_get_msgtype(const struct ptp_header *hdr, unsigned int type) { u8 msgtype; if (unlikely(type & PTP_CLASS_V1)) { /* msg type is located at the control field for ptp v1 */ msgtype = hdr->control; } else { msgtype = hdr->tsmt & 0x0f; } return msgtype; } void __init ptp_classifier_init(void); #else static inline void ptp_classifier_init(void) { } static inline unsigned int ptp_classify_raw(struct sk_buff *skb) { return PTP_CLASS_NONE; } static inline struct ptp_header *ptp_parse_header(struct sk_buff *skb, unsigned int type) { return NULL; } static inline u8 ptp_get_msgtype(const struct ptp_header *hdr, unsigned int type) { /* The return is meaningless. The stub function would not be * executed since no available header from ptp_parse_header. */ return PTP_MSGTYPE_SYNC; } #endif #endif /* _PTP_CLASSIFY_H_ */