diff options
Diffstat (limited to 'include/linux/ptp_classify.h')
| -rw-r--r-- | include/linux/ptp_classify.h | 194 |
1 files changed, 179 insertions, 15 deletions
diff --git a/include/linux/ptp_classify.h b/include/linux/ptp_classify.h index a079656b614c..3a74f69e0b59 100644 --- a/include/linux/ptp_classify.h +++ b/include/linux/ptp_classify.h @@ -1,30 +1,21 @@ +/* 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 - * - * 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/unaligned.h> #include <linux/ip.h> +#include <linux/ktime.h> #include <linux/skbuff.h> +#include <linux/udp.h> +#include <net/checksum.h> #define PTP_CLASS_NONE 0x00 /* not a PTP event message */ #define PTP_CLASS_V1 0x01 /* protocol version 1 */ @@ -44,12 +35,20 @@ #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 -#define OFF_PTP_CONTROL 32 /* PTPv1 only */ + +/* 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 @@ -57,6 +56,30 @@ #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 @@ -70,10 +93,151 @@ */ 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_check_diff8 - Computes new checksum (when altering a 64-bit field) + * @old: old field value + * @new: new field value + * @oldsum: previous checksum + * + * This function can be used to calculate a new checksum when only a single + * field is changed. Similar as ip_vs_check_diff*() in ip_vs.h. + * + * Return: Updated checksum + */ +static inline __wsum ptp_check_diff8(__be64 old, __be64 new, __wsum oldsum) +{ + __be64 diff[2] = { ~old, new }; + + return csum_partial(diff, sizeof(diff), oldsum); +} + +/** + * ptp_header_update_correction - Update PTP header's correction field + * @skb: packet buffer + * @type: type of the packet (see ptp_classify_raw()) + * @hdr: ptp header + * @correction: new correction value + * + * This updates the correction field of a PTP header and updates the UDP + * checksum (if UDP is used as transport). It is needed for hardware capable of + * one-step P2P that does not already modify the correction field of Pdelay_Req + * event messages on ingress. + */ +static inline +void ptp_header_update_correction(struct sk_buff *skb, unsigned int type, + struct ptp_header *hdr, s64 correction) +{ + __be64 correction_old; + struct udphdr *uhdr; + + /* previous correction value is required for checksum update. */ + memcpy(&correction_old, &hdr->correction, sizeof(correction_old)); + + /* write new correction value */ + put_unaligned_be64((u64)correction, &hdr->correction); + + switch (type & PTP_CLASS_PMASK) { + case PTP_CLASS_IPV4: + case PTP_CLASS_IPV6: + /* locate udp header */ + uhdr = (struct udphdr *)((char *)hdr - sizeof(struct udphdr)); + break; + default: + return; + } + + /* update checksum */ + uhdr->check = csum_fold(ptp_check_diff8(correction_old, + hdr->correction, + ~csum_unfold(uhdr->check))); + if (!uhdr->check) + uhdr->check = CSUM_MANGLED_0; + + skb->ip_summed = CHECKSUM_NONE; +} + +/** + * 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; +} + +static inline +void ptp_header_update_correction(struct sk_buff *skb, unsigned int type, + struct ptp_header *hdr, s64 correction) +{ +} #endif #endif /* _PTP_CLASSIFY_H_ */ |