linux-stable/include/linux/ptp_classify.h
Vladimir Oltean ec15baec32 net: ptp: add a definition for the UDP port for IEEE 1588 general messages
As opposed to event messages (Sync, PdelayReq etc) which require
timestamping, general messages (Announce, FollowUp etc) do not.
In PTP they are part of different streams of data.

IEEE 1588-2008 Annex D.2 "UDP port numbers" states that the UDP
destination port assigned by IANA is 319 for event messages, and 320 for
general messages. Yet the kernel seems to be missing the definition for
general messages. This patch adds it.

Signed-off-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Acked-by: Richard Cochran <richardcochran@gmail.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2021-11-26 11:38:20 -08:00

152 lines
4.4 KiB
C

/* 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
/* 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_ */