linux/net/hsr/hsr_main.h
Kurt Kanzenbach bf08824a0f flow_dissector: Add support for HSR
Network drivers such as igb or igc call eth_get_headlen() to determine the
header length for their to be constructed skbs in receive path.

When running HSR on top of these drivers, it results in triggering BUG_ON() in
skb_pull(). The reason is the skb headlen is not sufficient for HSR to work
correctly. skb_pull() notices that.

For instance, eth_get_headlen() returns 14 bytes for TCP traffic over HSR which
is not correct. The problem is, the flow dissection code does not take HSR into
account. Therefore, add support for it.

Reported-by: Anthony Harivel <anthony.harivel@linutronix.de>
Signed-off-by: Kurt Kanzenbach <kurt@linutronix.de>
Link: https://lore.kernel.org/r/20220228195856.88187-1-kurt@linutronix.de
Signed-off-by: Jakub Kicinski <kuba@kernel.org>
2022-03-02 22:44:49 -08:00

293 lines
8.3 KiB
C

/* SPDX-License-Identifier: GPL-2.0 */
/* Copyright 2011-2014 Autronica Fire and Security AS
*
* Author(s):
* 2011-2014 Arvid Brodin, arvid.brodin@alten.se
*
* include file for HSR and PRP.
*/
#ifndef __HSR_PRIVATE_H
#define __HSR_PRIVATE_H
#include <linux/netdevice.h>
#include <linux/list.h>
#include <linux/if_vlan.h>
#include <linux/if_hsr.h>
/* Time constants as specified in the HSR specification (IEC-62439-3 2010)
* Table 8.
* All values in milliseconds.
*/
#define HSR_LIFE_CHECK_INTERVAL 2000 /* ms */
#define HSR_NODE_FORGET_TIME 60000 /* ms */
#define HSR_ANNOUNCE_INTERVAL 100 /* ms */
#define HSR_ENTRY_FORGET_TIME 400 /* ms */
/* By how much may slave1 and slave2 timestamps of latest received frame from
* each node differ before we notify of communication problem?
*/
#define MAX_SLAVE_DIFF 3000 /* ms */
#define HSR_SEQNR_START (USHRT_MAX - 1024)
#define HSR_SUP_SEQNR_START (HSR_SEQNR_START / 2)
/* How often shall we check for broken ring and remove node entries older than
* HSR_NODE_FORGET_TIME?
*/
#define PRUNE_PERIOD 3000 /* ms */
#define HSR_TLV_EOT 0 /* End of TLVs */
#define HSR_TLV_ANNOUNCE 22
#define HSR_TLV_LIFE_CHECK 23
/* PRP V1 life check for Duplicate discard */
#define PRP_TLV_LIFE_CHECK_DD 20
/* PRP V1 life check for Duplicate Accept */
#define PRP_TLV_LIFE_CHECK_DA 21
/* PRP V1 life redundancy box MAC address */
#define PRP_TLV_REDBOX_MAC 30
#define HSR_V1_SUP_LSDUSIZE 52
#define HSR_HSIZE_SHIFT 8
#define HSR_HSIZE BIT(HSR_HSIZE_SHIFT)
/* The helper functions below assumes that 'path' occupies the 4 most
* significant bits of the 16-bit field shared by 'path' and 'LSDU_size' (or
* equivalently, the 4 most significant bits of HSR tag byte 14).
*
* This is unclear in the IEC specification; its definition of MAC addresses
* indicates the spec is written with the least significant bit first (to the
* left). This, however, would mean that the LSDU field would be split in two
* with the path field in-between, which seems strange. I'm guessing the MAC
* address definition is in error.
*/
static inline void set_hsr_tag_path(struct hsr_tag *ht, u16 path)
{
ht->path_and_LSDU_size =
htons((ntohs(ht->path_and_LSDU_size) & 0x0FFF) | (path << 12));
}
static inline void set_hsr_tag_LSDU_size(struct hsr_tag *ht, u16 LSDU_size)
{
ht->path_and_LSDU_size = htons((ntohs(ht->path_and_LSDU_size) &
0xF000) | (LSDU_size & 0x0FFF));
}
struct hsr_ethhdr {
struct ethhdr ethhdr;
struct hsr_tag hsr_tag;
} __packed;
struct hsr_vlan_ethhdr {
struct vlan_ethhdr vlanhdr;
struct hsr_tag hsr_tag;
} __packed;
struct hsr_sup_tlv {
u8 HSR_TLV_type;
u8 HSR_TLV_length;
};
/* HSR/PRP Supervision Frame data types.
* Field names as defined in the IEC:2010 standard for HSR.
*/
struct hsr_sup_tag {
__be16 path_and_HSR_ver;
__be16 sequence_nr;
struct hsr_sup_tlv tlv;
} __packed;
struct hsr_sup_payload {
unsigned char macaddress_A[ETH_ALEN];
} __packed;
static inline void set_hsr_stag_path(struct hsr_sup_tag *hst, u16 path)
{
set_hsr_tag_path((struct hsr_tag *)hst, path);
}
static inline void set_hsr_stag_HSR_ver(struct hsr_sup_tag *hst, u16 HSR_ver)
{
set_hsr_tag_LSDU_size((struct hsr_tag *)hst, HSR_ver);
}
struct hsrv0_ethhdr_sp {
struct ethhdr ethhdr;
struct hsr_sup_tag hsr_sup;
} __packed;
struct hsrv1_ethhdr_sp {
struct ethhdr ethhdr;
struct hsr_tag hsr;
struct hsr_sup_tag hsr_sup;
} __packed;
enum hsr_port_type {
HSR_PT_NONE = 0, /* Must be 0, used by framereg */
HSR_PT_SLAVE_A,
HSR_PT_SLAVE_B,
HSR_PT_INTERLINK,
HSR_PT_MASTER,
HSR_PT_PORTS, /* This must be the last item in the enum */
};
/* PRP Redunancy Control Trailor (RCT).
* As defined in IEC-62439-4:2012, the PRP RCT is really { sequence Nr,
* Lan indentifier (LanId), LSDU_size and PRP_suffix = 0x88FB }.
*
* Field names as defined in the IEC:2012 standard for PRP.
*/
struct prp_rct {
__be16 sequence_nr;
__be16 lan_id_and_LSDU_size;
__be16 PRP_suffix;
} __packed;
static inline u16 get_prp_LSDU_size(struct prp_rct *rct)
{
return ntohs(rct->lan_id_and_LSDU_size) & 0x0FFF;
}
static inline void set_prp_lan_id(struct prp_rct *rct, u16 lan_id)
{
rct->lan_id_and_LSDU_size = htons((ntohs(rct->lan_id_and_LSDU_size) &
0x0FFF) | (lan_id << 12));
}
static inline void set_prp_LSDU_size(struct prp_rct *rct, u16 LSDU_size)
{
rct->lan_id_and_LSDU_size = htons((ntohs(rct->lan_id_and_LSDU_size) &
0xF000) | (LSDU_size & 0x0FFF));
}
struct hsr_port {
struct list_head port_list;
struct net_device *dev;
struct hsr_priv *hsr;
enum hsr_port_type type;
};
struct hsr_frame_info;
struct hsr_node;
struct hsr_proto_ops {
/* format and send supervision frame */
void (*send_sv_frame)(struct hsr_port *port, unsigned long *interval);
void (*handle_san_frame)(bool san, enum hsr_port_type port,
struct hsr_node *node);
bool (*drop_frame)(struct hsr_frame_info *frame, struct hsr_port *port);
struct sk_buff * (*get_untagged_frame)(struct hsr_frame_info *frame,
struct hsr_port *port);
struct sk_buff * (*create_tagged_frame)(struct hsr_frame_info *frame,
struct hsr_port *port);
int (*fill_frame_info)(__be16 proto, struct sk_buff *skb,
struct hsr_frame_info *frame);
bool (*invalid_dan_ingress_frame)(__be16 protocol);
void (*update_san_info)(struct hsr_node *node, bool is_sup);
};
struct hsr_priv {
struct rcu_head rcu_head;
struct list_head ports;
struct hlist_head node_db[HSR_HSIZE]; /* Known HSR nodes */
struct hlist_head self_node_db; /* MACs of slaves */
struct timer_list announce_timer; /* Supervision frame dispatch */
struct timer_list prune_timer;
int announce_count;
u16 sequence_nr;
u16 sup_sequence_nr; /* For HSRv1 separate seq_nr for supervision */
enum hsr_version prot_version; /* Indicate if HSRv0, HSRv1 or PRPv1 */
spinlock_t seqnr_lock; /* locking for sequence_nr */
spinlock_t list_lock; /* locking for node list */
struct hsr_proto_ops *proto_ops;
u32 hash_buckets;
u32 hash_seed;
#define PRP_LAN_ID 0x5 /* 0x1010 for A and 0x1011 for B. Bit 0 is set
* based on SLAVE_A or SLAVE_B
*/
u8 net_id; /* for PRP, it occupies most significant 3 bits
* of lan_id
*/
unsigned char sup_multicast_addr[ETH_ALEN] __aligned(sizeof(u16));
/* Align to u16 boundary to avoid unaligned access
* in ether_addr_equal
*/
#ifdef CONFIG_DEBUG_FS
struct dentry *node_tbl_root;
#endif
};
#define hsr_for_each_port(hsr, port) \
list_for_each_entry_rcu((port), &(hsr)->ports, port_list)
struct hsr_port *hsr_port_get_hsr(struct hsr_priv *hsr, enum hsr_port_type pt);
/* Caller must ensure skb is a valid HSR frame */
static inline u16 hsr_get_skb_sequence_nr(struct sk_buff *skb)
{
struct hsr_ethhdr *hsr_ethhdr;
hsr_ethhdr = (struct hsr_ethhdr *)skb_mac_header(skb);
return ntohs(hsr_ethhdr->hsr_tag.sequence_nr);
}
static inline struct prp_rct *skb_get_PRP_rct(struct sk_buff *skb)
{
unsigned char *tail = skb_tail_pointer(skb) - HSR_HLEN;
struct prp_rct *rct = (struct prp_rct *)tail;
if (rct->PRP_suffix == htons(ETH_P_PRP))
return rct;
return NULL;
}
/* Assume caller has confirmed this skb is PRP suffixed */
static inline u16 prp_get_skb_sequence_nr(struct prp_rct *rct)
{
return ntohs(rct->sequence_nr);
}
/* assume there is a valid rct */
static inline bool prp_check_lsdu_size(struct sk_buff *skb,
struct prp_rct *rct,
bool is_sup)
{
struct ethhdr *ethhdr;
int expected_lsdu_size;
if (is_sup) {
expected_lsdu_size = HSR_V1_SUP_LSDUSIZE;
} else {
ethhdr = (struct ethhdr *)skb_mac_header(skb);
expected_lsdu_size = skb->len - 14;
if (ethhdr->h_proto == htons(ETH_P_8021Q))
expected_lsdu_size -= 4;
}
return (expected_lsdu_size == get_prp_LSDU_size(rct));
}
#if IS_ENABLED(CONFIG_DEBUG_FS)
void hsr_debugfs_rename(struct net_device *dev);
void hsr_debugfs_init(struct hsr_priv *priv, struct net_device *hsr_dev);
void hsr_debugfs_term(struct hsr_priv *priv);
void hsr_debugfs_create_root(void);
void hsr_debugfs_remove_root(void);
#else
static inline void hsr_debugfs_rename(struct net_device *dev)
{
}
static inline void hsr_debugfs_init(struct hsr_priv *priv,
struct net_device *hsr_dev)
{}
static inline void hsr_debugfs_term(struct hsr_priv *priv)
{}
static inline void hsr_debugfs_create_root(void)
{}
static inline void hsr_debugfs_remove_root(void)
{}
#endif
#endif /* __HSR_PRIVATE_H */