xref: /linux/net/hsr/hsr_main.h (revision 26fbb4c8c7c3ee9a4c3b4de555a8587b5a19154e)
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 
17 /* Time constants as specified in the HSR specification (IEC-62439-3 2010)
18  * Table 8.
19  * All values in milliseconds.
20  */
21 #define HSR_LIFE_CHECK_INTERVAL		 2000 /* ms */
22 #define HSR_NODE_FORGET_TIME		60000 /* ms */
23 #define HSR_ANNOUNCE_INTERVAL		  100 /* ms */
24 
25 /* By how much may slave1 and slave2 timestamps of latest received frame from
26  * each node differ before we notify of communication problem?
27  */
28 #define MAX_SLAVE_DIFF			 3000 /* ms */
29 #define HSR_SEQNR_START			(USHRT_MAX - 1024)
30 #define HSR_SUP_SEQNR_START		(HSR_SEQNR_START / 2)
31 
32 /* How often shall we check for broken ring and remove node entries older than
33  * HSR_NODE_FORGET_TIME?
34  */
35 #define PRUNE_PERIOD			 3000 /* ms */
36 
37 #define HSR_TLV_ANNOUNCE		   22
38 #define HSR_TLV_LIFE_CHECK		   23
39 /* PRP V1 life check for Duplicate discard */
40 #define PRP_TLV_LIFE_CHECK_DD		   20
41 /* PRP V1 life check for Duplicate Accept */
42 #define PRP_TLV_LIFE_CHECK_DA		   21
43 
44 /* HSR Tag.
45  * As defined in IEC-62439-3:2010, the HSR tag is really { ethertype = 0x88FB,
46  * path, LSDU_size, sequence Nr }. But we let eth_header() create { h_dest,
47  * h_source, h_proto = 0x88FB }, and add { path, LSDU_size, sequence Nr,
48  * encapsulated protocol } instead.
49  *
50  * Field names as defined in the IEC:2010 standard for HSR.
51  */
52 struct hsr_tag {
53 	__be16		path_and_LSDU_size;
54 	__be16		sequence_nr;
55 	__be16		encap_proto;
56 } __packed;
57 
58 #define HSR_HLEN	6
59 
60 #define HSR_V1_SUP_LSDUSIZE		52
61 
62 /* The helper functions below assumes that 'path' occupies the 4 most
63  * significant bits of the 16-bit field shared by 'path' and 'LSDU_size' (or
64  * equivalently, the 4 most significant bits of HSR tag byte 14).
65  *
66  * This is unclear in the IEC specification; its definition of MAC addresses
67  * indicates the spec is written with the least significant bit first (to the
68  * left). This, however, would mean that the LSDU field would be split in two
69  * with the path field in-between, which seems strange. I'm guessing the MAC
70  * address definition is in error.
71  */
72 
73 static inline void set_hsr_tag_path(struct hsr_tag *ht, u16 path)
74 {
75 	ht->path_and_LSDU_size =
76 		htons((ntohs(ht->path_and_LSDU_size) & 0x0FFF) | (path << 12));
77 }
78 
79 static inline void set_hsr_tag_LSDU_size(struct hsr_tag *ht, u16 LSDU_size)
80 {
81 	ht->path_and_LSDU_size = htons((ntohs(ht->path_and_LSDU_size) &
82 				       0xF000) | (LSDU_size & 0x0FFF));
83 }
84 
85 struct hsr_ethhdr {
86 	struct ethhdr	ethhdr;
87 	struct hsr_tag	hsr_tag;
88 } __packed;
89 
90 struct hsr_vlan_ethhdr {
91 	struct vlan_ethhdr vlanhdr;
92 	struct hsr_tag	hsr_tag;
93 } __packed;
94 
95 /* HSR/PRP Supervision Frame data types.
96  * Field names as defined in the IEC:2010 standard for HSR.
97  */
98 struct hsr_sup_tag {
99 	__be16		path_and_HSR_ver;
100 	__be16		sequence_nr;
101 	__u8		HSR_TLV_type;
102 	__u8		HSR_TLV_length;
103 } __packed;
104 
105 struct hsr_sup_payload {
106 	unsigned char	macaddress_A[ETH_ALEN];
107 } __packed;
108 
109 static inline void set_hsr_stag_path(struct hsr_sup_tag *hst, u16 path)
110 {
111 	set_hsr_tag_path((struct hsr_tag *)hst, path);
112 }
113 
114 static inline void set_hsr_stag_HSR_ver(struct hsr_sup_tag *hst, u16 HSR_ver)
115 {
116 	set_hsr_tag_LSDU_size((struct hsr_tag *)hst, HSR_ver);
117 }
118 
119 struct hsrv0_ethhdr_sp {
120 	struct ethhdr		ethhdr;
121 	struct hsr_sup_tag	hsr_sup;
122 } __packed;
123 
124 struct hsrv1_ethhdr_sp {
125 	struct ethhdr		ethhdr;
126 	struct hsr_tag		hsr;
127 	struct hsr_sup_tag	hsr_sup;
128 } __packed;
129 
130 enum hsr_port_type {
131 	HSR_PT_NONE = 0,	/* Must be 0, used by framereg */
132 	HSR_PT_SLAVE_A,
133 	HSR_PT_SLAVE_B,
134 	HSR_PT_INTERLINK,
135 	HSR_PT_MASTER,
136 	HSR_PT_PORTS,	/* This must be the last item in the enum */
137 };
138 
139 /* PRP Redunancy Control Trailor (RCT).
140  * As defined in IEC-62439-4:2012, the PRP RCT is really { sequence Nr,
141  * Lan indentifier (LanId), LSDU_size and PRP_suffix = 0x88FB }.
142  *
143  * Field names as defined in the IEC:2012 standard for PRP.
144  */
145 struct prp_rct {
146 	__be16          sequence_nr;
147 	__be16          lan_id_and_LSDU_size;
148 	__be16          PRP_suffix;
149 } __packed;
150 
151 static inline u16 get_prp_LSDU_size(struct prp_rct *rct)
152 {
153 	return ntohs(rct->lan_id_and_LSDU_size) & 0x0FFF;
154 }
155 
156 static inline void set_prp_lan_id(struct prp_rct *rct, u16 lan_id)
157 {
158 	rct->lan_id_and_LSDU_size = htons((ntohs(rct->lan_id_and_LSDU_size) &
159 					  0x0FFF) | (lan_id << 12));
160 }
161 static inline void set_prp_LSDU_size(struct prp_rct *rct, u16 LSDU_size)
162 {
163 	rct->lan_id_and_LSDU_size = htons((ntohs(rct->lan_id_and_LSDU_size) &
164 					  0xF000) | (LSDU_size & 0x0FFF));
165 }
166 
167 struct hsr_port {
168 	struct list_head	port_list;
169 	struct net_device	*dev;
170 	struct hsr_priv		*hsr;
171 	enum hsr_port_type	type;
172 };
173 
174 /* used by driver internally to differentiate various protocols */
175 enum hsr_version {
176 	HSR_V0 = 0,
177 	HSR_V1,
178 	PRP_V1,
179 };
180 
181 struct hsr_frame_info;
182 struct hsr_node;
183 
184 struct hsr_proto_ops {
185 	/* format and send supervision frame */
186 	void (*send_sv_frame)(struct hsr_port *port, unsigned long *interval);
187 	void (*handle_san_frame)(bool san, enum hsr_port_type port,
188 				 struct hsr_node *node);
189 	bool (*drop_frame)(struct hsr_frame_info *frame, struct hsr_port *port);
190 	struct sk_buff * (*get_untagged_frame)(struct hsr_frame_info *frame,
191 					       struct hsr_port *port);
192 	struct sk_buff * (*create_tagged_frame)(struct hsr_frame_info *frame,
193 						struct hsr_port *port);
194 	void (*fill_frame_info)(__be16 proto, struct sk_buff *skb,
195 				struct hsr_frame_info *frame);
196 	bool (*invalid_dan_ingress_frame)(__be16 protocol);
197 	void (*update_san_info)(struct hsr_node *node, bool is_sup);
198 };
199 
200 struct hsr_priv {
201 	struct rcu_head		rcu_head;
202 	struct list_head	ports;
203 	struct list_head	node_db;	/* Known HSR nodes */
204 	struct list_head	self_node_db;	/* MACs of slaves */
205 	struct timer_list	announce_timer;	/* Supervision frame dispatch */
206 	struct timer_list	prune_timer;
207 	int announce_count;
208 	u16 sequence_nr;
209 	u16 sup_sequence_nr;	/* For HSRv1 separate seq_nr for supervision */
210 	enum hsr_version prot_version;	/* Indicate if HSRv0, HSRv1 or PRPv1 */
211 	spinlock_t seqnr_lock;	/* locking for sequence_nr */
212 	spinlock_t list_lock;	/* locking for node list */
213 	struct hsr_proto_ops	*proto_ops;
214 #define PRP_LAN_ID	0x5     /* 0x1010 for A and 0x1011 for B. Bit 0 is set
215 				 * based on SLAVE_A or SLAVE_B
216 				 */
217 	u8 net_id;		/* for PRP, it occupies most significant 3 bits
218 				 * of lan_id
219 				 */
220 	unsigned char		sup_multicast_addr[ETH_ALEN];
221 #ifdef	CONFIG_DEBUG_FS
222 	struct dentry *node_tbl_root;
223 #endif
224 };
225 
226 #define hsr_for_each_port(hsr, port) \
227 	list_for_each_entry_rcu((port), &(hsr)->ports, port_list)
228 
229 struct hsr_port *hsr_port_get_hsr(struct hsr_priv *hsr, enum hsr_port_type pt);
230 
231 /* Caller must ensure skb is a valid HSR frame */
232 static inline u16 hsr_get_skb_sequence_nr(struct sk_buff *skb)
233 {
234 	struct hsr_ethhdr *hsr_ethhdr;
235 
236 	hsr_ethhdr = (struct hsr_ethhdr *)skb_mac_header(skb);
237 	return ntohs(hsr_ethhdr->hsr_tag.sequence_nr);
238 }
239 
240 static inline struct prp_rct *skb_get_PRP_rct(struct sk_buff *skb)
241 {
242 	unsigned char *tail = skb_tail_pointer(skb) - HSR_HLEN;
243 
244 	struct prp_rct *rct = (struct prp_rct *)tail;
245 
246 	if (rct->PRP_suffix == htons(ETH_P_PRP))
247 		return rct;
248 
249 	return NULL;
250 }
251 
252 /* Assume caller has confirmed this skb is PRP suffixed */
253 static inline u16 prp_get_skb_sequence_nr(struct prp_rct *rct)
254 {
255 	return ntohs(rct->sequence_nr);
256 }
257 
258 static inline u16 get_prp_lan_id(struct prp_rct *rct)
259 {
260 	return ntohs(rct->lan_id_and_LSDU_size) >> 12;
261 }
262 
263 /* assume there is a valid rct */
264 static inline bool prp_check_lsdu_size(struct sk_buff *skb,
265 				       struct prp_rct *rct,
266 				       bool is_sup)
267 {
268 	struct ethhdr *ethhdr;
269 	int expected_lsdu_size;
270 
271 	if (is_sup) {
272 		expected_lsdu_size = HSR_V1_SUP_LSDUSIZE;
273 	} else {
274 		ethhdr = (struct ethhdr *)skb_mac_header(skb);
275 		expected_lsdu_size = skb->len - 14;
276 		if (ethhdr->h_proto == htons(ETH_P_8021Q))
277 			expected_lsdu_size -= 4;
278 	}
279 
280 	return (expected_lsdu_size == get_prp_LSDU_size(rct));
281 }
282 
283 #if IS_ENABLED(CONFIG_DEBUG_FS)
284 void hsr_debugfs_rename(struct net_device *dev);
285 void hsr_debugfs_init(struct hsr_priv *priv, struct net_device *hsr_dev);
286 void hsr_debugfs_term(struct hsr_priv *priv);
287 void hsr_debugfs_create_root(void);
288 void hsr_debugfs_remove_root(void);
289 #else
290 static inline void hsr_debugfs_rename(struct net_device *dev)
291 {
292 }
293 static inline void hsr_debugfs_init(struct hsr_priv *priv,
294 				    struct net_device *hsr_dev)
295 {}
296 static inline void hsr_debugfs_term(struct hsr_priv *priv)
297 {}
298 static inline void hsr_debugfs_create_root(void)
299 {}
300 static inline void hsr_debugfs_remove_root(void)
301 {}
302 #endif
303 
304 #endif /*  __HSR_PRIVATE_H */
305