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Diffstat (limited to 'include/linux/ptp_classify.h')
| -rw-r--r-- | include/linux/ptp_classify.h | 170 |
1 files changed, 170 insertions, 0 deletions
diff --git a/include/linux/ptp_classify.h b/include/linux/ptp_classify.h new file mode 100644 index 000000000..2b6ea36ad --- /dev/null +++ b/include/linux/ptp_classify.h @@ -0,0 +1,170 @@ +/* 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_PORT 320 +#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 + +/* PTP header flag fields */ +#define PTP_FLAG_TWOSTEP BIT(1) + +/* 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; +} + +/** + * ptp_msg_is_sync - Evaluates whether the given skb is a PTP Sync message + * @skb: packet buffer + * @type: type of the packet (see ptp_classify_raw()) + * + * This function evaluates whether the given skb is a PTP Sync message. + * + * Return: true if sync message, false otherwise + */ +bool ptp_msg_is_sync(struct sk_buff *skb, unsigned int type); + +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; +} +static inline bool ptp_msg_is_sync(struct sk_buff *skb, unsigned int type) +{ + return false; +} +#endif +#endif /* _PTP_CLASSIFY_H_ */ |