/*
* PTP 1588 support
*
* This file implements a BPF that recognizes PTP event messages.
*
* Copyright (C) 2010 OMICRON electronics GmbH
*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
#ifndef _PTP_CLASSIFY_H_
#define _PTP_CLASSIFY_H_
#include <linux/if_ether.h>
#include <linux/if_vlan.h>
#include <linux/filter.h>
#ifdef __KERNEL__
#include <linux/in.h>
#else
#include <netinet/in.h>
#endif
#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 0x30 /* event in a L2 packet */
#define PTP_CLASS_VLAN 0x40 /* event in a VLAN tagged L2 packet */
#define PTP_CLASS_PMASK 0xf0 /* mask for the packet type field */
#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_EV_PORT 319
#define OFF_ETYPE 12
#define OFF_IHL 14
#define OFF_FRAG 20
#define OFF_PROTO4 23
#define OFF_NEXT 6
#define OFF_UDP_DST 2
#define IP6_HLEN 40
#define UDP_HLEN 8
#define RELOFF_DST4 (ETH_HLEN + OFF_UDP_DST)
#define OFF_DST6 (ETH_HLEN + IP6_HLEN + OFF_UDP_DST)
#define OFF_PTP6 (ETH_HLEN + IP6_HLEN + UDP_HLEN)
#define OP_AND (BPF_ALU | BPF_AND | BPF_K)
#define OP_JEQ (BPF_JMP | BPF_JEQ | BPF_K)
#define OP_JSET (BPF_JMP | BPF_JSET | BPF_K)
#define OP_LDB (BPF_LD | BPF_B | BPF_ABS)
#define OP_LDH (BPF_LD | BPF_H | BPF_ABS)
#define OP_LDHI (BPF_LD | BPF_H | BPF_IND)
#define OP_LDX (BPF_LDX | BPF_B | BPF_MSH)
#define OP_OR (BPF_ALU | BPF_OR | BPF_K)
#define OP_RETA (BPF_RET | BPF_A)
#define OP_RETK (BPF_RET | BPF_K)
static inline int ptp_filter_init(struct sock_filter *f, int len)
{
if (OP_LDH == f[0].code)
return sk_chk_filter(f, len);
else
return 0;
}
#define PTP_FILTER \
{OP_LDH, 0, 0, OFF_ETYPE }, /* */ \
{OP_JEQ, 0, 12, ETH_P_IP }, /* f goto L20 */ \
{OP_LDB, 0, 0, OFF_PROTO4 }, /* */ \
{OP_JEQ, 0, 9, IPPROTO_UDP }, /* f goto L10 */ \
{OP_LDH, 0, 0, OFF_FRAG }, /* */ \
{OP_JSET, 7, 0, 0x1fff }, /* t goto L11 */ \
{OP_LDX, 0, 0, OFF_IHL }, /* */ \
{OP_LDHI, 0, 0, RELOFF_DST4 }, /* */ \
{OP_JEQ, 0, 4, PTP_EV_PORT }, /* f goto L12 */ \
{OP_LDHI, 0, 0, ETH_HLEN + UDP_HLEN }, /* */ \
{OP_AND, 0, 0, PTP_CLASS_VMASK }, /* */ \
{OP_OR, 0, 0, PTP_CLASS_IPV4 }, /* */ \
{OP_RETA, 0, 0, 0 }, /* */ \
/*L1x*/ {OP_RETK, 0, 0, PTP_CLASS_NONE }, /* */ \
/*L20*/ {OP_JEQ, 0, 9, ETH_P_IPV6 }, /* f goto L40 */ \
{OP_LDB, 0, 0, ETH_HLEN + OFF_NEXT }, /* */ \
{OP_JEQ, 0, 6, IPPROTO_UDP }, /* f goto L30 */ \
{OP_LDH, 0, 0, OFF_DST6 }, /* */ \
{OP_JEQ, 0, 4, PTP_EV_PORT }, /* f goto L31 */ \
{OP_LDH, 0, 0, OFF_PTP6 }, /* */ \
{OP_AND, 0, 0, PTP_CLASS_VMASK }, /* */ \
{OP_OR, 0, 0, PTP_CLASS_IPV6 }, /* */ \
{OP_RETA, 0, 0, 0 }, /* */ \
/*L3x*/ {OP_RETK, 0, 0, PTP_CLASS_NONE }, /* */ \
/*L40*/ {OP_JEQ, 0, 6, ETH_P_8021Q }, /* f goto L50 */ \
{OP_LDH, 0, 0, OFF_ETYPE + 4 }, /* */ \
{OP_JEQ, 0, 9, ETH_P_1588 }, /* f goto L60 */ \
{OP_LDH, 0, 0, ETH_HLEN + VLAN_HLEN }, /* */ \
{OP_AND, 0, 0, PTP_CLASS_VMASK }, /* */ \
{OP_OR, 0, 0, PTP_CLASS_VLAN }, /* */ \
{OP_RETA, 0, 0, 0 }, /* */ \
/*L50*/ {OP_JEQ, 0, 4, ETH_P_1588 }, /* f goto L61 */ \
{OP_LDH, 0, 0, ETH_HLEN }, /* */ \
{OP_AND, 0, 0, PTP_CLASS_VMASK }, /* */ \
{OP_OR, 0, 0, PTP_CLASS_L2 }, /* */ \
{OP_RETA, 0, 0, 0 }, /* */ \
/*L6x*/ {OP_RETK, 0, 0, PTP_CLASS_NONE },
#endif
