xref: /linux/net/hsr/hsr_main.h (revision 6a143a7cf94730f57544ea14a987dc025364dbb8)
1 /* SPDX-License-Identifier: GPL-2.0 */
2 /* Copyright 2011-2014 Autronica Fire and Security AS
3  *
4  * Author(s):
5  *	2011-2014 Arvid Brodin, arvid.brodin@alten.se
6  *
7  * include file for HSR and PRP.
8  */
9 
10 #ifndef __HSR_PRIVATE_H
11 #define __HSR_PRIVATE_H
12 
13 #include <linux/netdevice.h>
14 #include <linux/list.h>
15 #include <linux/if_vlan.h>
16 #include <linux/if_hsr.h>
17 
18 /* Time constants as specified in the HSR specification (IEC-62439-3 2010)
19  * Table 8.
20  * All values in milliseconds.
21  */
22 #define HSR_LIFE_CHECK_INTERVAL		 2000 /* ms */
23 #define HSR_NODE_FORGET_TIME		60000 /* ms */
24 #define HSR_ANNOUNCE_INTERVAL		  100 /* ms */
25 #define HSR_ENTRY_FORGET_TIME		  400 /* ms */
26 
27 /* By how much may slave1 and slave2 timestamps of latest received frame from
28  * each node differ before we notify of communication problem?
29  */
30 #define MAX_SLAVE_DIFF			 3000 /* ms */
31 #define HSR_SEQNR_START			(USHRT_MAX - 1024)
32 #define HSR_SUP_SEQNR_START		(HSR_SEQNR_START / 2)
33 
34 /* How often shall we check for broken ring and remove node entries older than
35  * HSR_NODE_FORGET_TIME?
36  */
37 #define PRUNE_PERIOD			 3000 /* ms */
38 
39 #define HSR_TLV_ANNOUNCE		   22
40 #define HSR_TLV_LIFE_CHECK		   23
41 /* PRP V1 life check for Duplicate discard */
42 #define PRP_TLV_LIFE_CHECK_DD		   20
43 /* PRP V1 life check for Duplicate Accept */
44 #define PRP_TLV_LIFE_CHECK_DA		   21
45 
46 /* HSR Tag.
47  * As defined in IEC-62439-3:2010, the HSR tag is really { ethertype = 0x88FB,
48  * path, LSDU_size, sequence Nr }. But we let eth_header() create { h_dest,
49  * h_source, h_proto = 0x88FB }, and add { path, LSDU_size, sequence Nr,
50  * encapsulated protocol } instead.
51  *
52  * Field names as defined in the IEC:2010 standard for HSR.
53  */
54 struct hsr_tag {
55 	__be16		path_and_LSDU_size;
56 	__be16		sequence_nr;
57 	__be16		encap_proto;
58 } __packed;
59 
60 #define HSR_HLEN	6
61 
62 #define HSR_V1_SUP_LSDUSIZE		52
63 
64 /* The helper functions below assumes that 'path' occupies the 4 most
65  * significant bits of the 16-bit field shared by 'path' and 'LSDU_size' (or
66  * equivalently, the 4 most significant bits of HSR tag byte 14).
67  *
68  * This is unclear in the IEC specification; its definition of MAC addresses
69  * indicates the spec is written with the least significant bit first (to the
70  * left). This, however, would mean that the LSDU field would be split in two
71  * with the path field in-between, which seems strange. I'm guessing the MAC
72  * address definition is in error.
73  */
74 
75 static inline void set_hsr_tag_path(struct hsr_tag *ht, u16 path)
76 {
77 	ht->path_and_LSDU_size =
78 		htons((ntohs(ht->path_and_LSDU_size) & 0x0FFF) | (path << 12));
79 }
80 
81 static inline void set_hsr_tag_LSDU_size(struct hsr_tag *ht, u16 LSDU_size)
82 {
83 	ht->path_and_LSDU_size = htons((ntohs(ht->path_and_LSDU_size) &
84 				       0xF000) | (LSDU_size & 0x0FFF));
85 }
86 
87 struct hsr_ethhdr {
88 	struct ethhdr	ethhdr;
89 	struct hsr_tag	hsr_tag;
90 } __packed;
91 
92 struct hsr_vlan_ethhdr {
93 	struct vlan_ethhdr vlanhdr;
94 	struct hsr_tag	hsr_tag;
95 } __packed;
96 
97 /* HSR/PRP Supervision Frame data types.
98  * Field names as defined in the IEC:2010 standard for HSR.
99  */
100 struct hsr_sup_tag {
101 	__be16		path_and_HSR_ver;
102 	__be16		sequence_nr;
103 	__u8		HSR_TLV_type;
104 	__u8		HSR_TLV_length;
105 } __packed;
106 
107 struct hsr_sup_payload {
108 	unsigned char	macaddress_A[ETH_ALEN];
109 } __packed;
110 
111 static inline void set_hsr_stag_path(struct hsr_sup_tag *hst, u16 path)
112 {
113 	set_hsr_tag_path((struct hsr_tag *)hst, path);
114 }
115 
116 static inline void set_hsr_stag_HSR_ver(struct hsr_sup_tag *hst, u16 HSR_ver)
117 {
118 	set_hsr_tag_LSDU_size((struct hsr_tag *)hst, HSR_ver);
119 }
120 
121 struct hsrv0_ethhdr_sp {
122 	struct ethhdr		ethhdr;
123 	struct hsr_sup_tag	hsr_sup;
124 } __packed;
125 
126 struct hsrv1_ethhdr_sp {
127 	struct ethhdr		ethhdr;
128 	struct hsr_tag		hsr;
129 	struct hsr_sup_tag	hsr_sup;
130 } __packed;
131 
132 enum hsr_port_type {
133 	HSR_PT_NONE = 0,	/* Must be 0, used by framereg */
134 	HSR_PT_SLAVE_A,
135 	HSR_PT_SLAVE_B,
136 	HSR_PT_INTERLINK,
137 	HSR_PT_MASTER,
138 	HSR_PT_PORTS,	/* This must be the last item in the enum */
139 };
140 
141 /* PRP Redunancy Control Trailor (RCT).
142  * As defined in IEC-62439-4:2012, the PRP RCT is really { sequence Nr,
143  * Lan indentifier (LanId), LSDU_size and PRP_suffix = 0x88FB }.
144  *
145  * Field names as defined in the IEC:2012 standard for PRP.
146  */
147 struct prp_rct {
148 	__be16          sequence_nr;
149 	__be16          lan_id_and_LSDU_size;
150 	__be16          PRP_suffix;
151 } __packed;
152 
153 static inline u16 get_prp_LSDU_size(struct prp_rct *rct)
154 {
155 	return ntohs(rct->lan_id_and_LSDU_size) & 0x0FFF;
156 }
157 
158 static inline void set_prp_lan_id(struct prp_rct *rct, u16 lan_id)
159 {
160 	rct->lan_id_and_LSDU_size = htons((ntohs(rct->lan_id_and_LSDU_size) &
161 					  0x0FFF) | (lan_id << 12));
162 }
163 static inline void set_prp_LSDU_size(struct prp_rct *rct, u16 LSDU_size)
164 {
165 	rct->lan_id_and_LSDU_size = htons((ntohs(rct->lan_id_and_LSDU_size) &
166 					  0xF000) | (LSDU_size & 0x0FFF));
167 }
168 
169 struct hsr_port {
170 	struct list_head	port_list;
171 	struct net_device	*dev;
172 	struct hsr_priv		*hsr;
173 	enum hsr_port_type	type;
174 };
175 
176 struct hsr_frame_info;
177 struct hsr_node;
178 
179 struct hsr_proto_ops {
180 	/* format and send supervision frame */
181 	void (*send_sv_frame)(struct hsr_port *port, unsigned long *interval);
182 	void (*handle_san_frame)(bool san, enum hsr_port_type port,
183 				 struct hsr_node *node);
184 	bool (*drop_frame)(struct hsr_frame_info *frame, struct hsr_port *port);
185 	struct sk_buff * (*get_untagged_frame)(struct hsr_frame_info *frame,
186 					       struct hsr_port *port);
187 	struct sk_buff * (*create_tagged_frame)(struct hsr_frame_info *frame,
188 						struct hsr_port *port);
189 	void (*fill_frame_info)(__be16 proto, struct sk_buff *skb,
190 				struct hsr_frame_info *frame);
191 	bool (*invalid_dan_ingress_frame)(__be16 protocol);
192 	void (*update_san_info)(struct hsr_node *node, bool is_sup);
193 };
194 
195 struct hsr_priv {
196 	struct rcu_head		rcu_head;
197 	struct list_head	ports;
198 	struct list_head	node_db;	/* Known HSR nodes */
199 	struct list_head	self_node_db;	/* MACs of slaves */
200 	struct timer_list	announce_timer;	/* Supervision frame dispatch */
201 	struct timer_list	prune_timer;
202 	int announce_count;
203 	u16 sequence_nr;
204 	u16 sup_sequence_nr;	/* For HSRv1 separate seq_nr for supervision */
205 	enum hsr_version prot_version;	/* Indicate if HSRv0, HSRv1 or PRPv1 */
206 	spinlock_t seqnr_lock;	/* locking for sequence_nr */
207 	spinlock_t list_lock;	/* locking for node list */
208 	struct hsr_proto_ops	*proto_ops;
209 #define PRP_LAN_ID	0x5     /* 0x1010 for A and 0x1011 for B. Bit 0 is set
210 				 * based on SLAVE_A or SLAVE_B
211 				 */
212 	u8 net_id;		/* for PRP, it occupies most significant 3 bits
213 				 * of lan_id
214 				 */
215 	unsigned char		sup_multicast_addr[ETH_ALEN] __aligned(sizeof(u16));
216 				/* Align to u16 boundary to avoid unaligned access
217 				 * in ether_addr_equal
218 				 */
219 #ifdef	CONFIG_DEBUG_FS
220 	struct dentry *node_tbl_root;
221 #endif
222 };
223 
224 #define hsr_for_each_port(hsr, port) \
225 	list_for_each_entry_rcu((port), &(hsr)->ports, port_list)
226 
227 struct hsr_port *hsr_port_get_hsr(struct hsr_priv *hsr, enum hsr_port_type pt);
228 
229 /* Caller must ensure skb is a valid HSR frame */
230 static inline u16 hsr_get_skb_sequence_nr(struct sk_buff *skb)
231 {
232 	struct hsr_ethhdr *hsr_ethhdr;
233 
234 	hsr_ethhdr = (struct hsr_ethhdr *)skb_mac_header(skb);
235 	return ntohs(hsr_ethhdr->hsr_tag.sequence_nr);
236 }
237 
238 static inline struct prp_rct *skb_get_PRP_rct(struct sk_buff *skb)
239 {
240 	unsigned char *tail = skb_tail_pointer(skb) - HSR_HLEN;
241 
242 	struct prp_rct *rct = (struct prp_rct *)tail;
243 
244 	if (rct->PRP_suffix == htons(ETH_P_PRP))
245 		return rct;
246 
247 	return NULL;
248 }
249 
250 /* Assume caller has confirmed this skb is PRP suffixed */
251 static inline u16 prp_get_skb_sequence_nr(struct prp_rct *rct)
252 {
253 	return ntohs(rct->sequence_nr);
254 }
255 
256 static inline u16 get_prp_lan_id(struct prp_rct *rct)
257 {
258 	return ntohs(rct->lan_id_and_LSDU_size) >> 12;
259 }
260 
261 /* assume there is a valid rct */
262 static inline bool prp_check_lsdu_size(struct sk_buff *skb,
263 				       struct prp_rct *rct,
264 				       bool is_sup)
265 {
266 	struct ethhdr *ethhdr;
267 	int expected_lsdu_size;
268 
269 	if (is_sup) {
270 		expected_lsdu_size = HSR_V1_SUP_LSDUSIZE;
271 	} else {
272 		ethhdr = (struct ethhdr *)skb_mac_header(skb);
273 		expected_lsdu_size = skb->len - 14;
274 		if (ethhdr->h_proto == htons(ETH_P_8021Q))
275 			expected_lsdu_size -= 4;
276 	}
277 
278 	return (expected_lsdu_size == get_prp_LSDU_size(rct));
279 }
280 
281 #if IS_ENABLED(CONFIG_DEBUG_FS)
282 void hsr_debugfs_rename(struct net_device *dev);
283 void hsr_debugfs_init(struct hsr_priv *priv, struct net_device *hsr_dev);
284 void hsr_debugfs_term(struct hsr_priv *priv);
285 void hsr_debugfs_create_root(void);
286 void hsr_debugfs_remove_root(void);
287 #else
288 static inline void hsr_debugfs_rename(struct net_device *dev)
289 {
290 }
291 static inline void hsr_debugfs_init(struct hsr_priv *priv,
292 				    struct net_device *hsr_dev)
293 {}
294 static inline void hsr_debugfs_term(struct hsr_priv *priv)
295 {}
296 static inline void hsr_debugfs_create_root(void)
297 {}
298 static inline void hsr_debugfs_remove_root(void)
299 {}
300 #endif
301 
302 #endif /*  __HSR_PRIVATE_H */
303