1 /* SPDX-License-Identifier: GPL-2.0+ */
2 /*
3  * MACsec netdev header, used for h/w accelerated implementations.
4  *
5  * Copyright (c) 2015 Sabrina Dubroca <sd@queasysnail.net>
6  */
7 #ifndef _NET_MACSEC_H_
8 #define _NET_MACSEC_H_
9 
10 #include <linux/u64_stats_sync.h>
11 #include <uapi/linux/if_link.h>
12 #include <uapi/linux/if_macsec.h>
13 
14 #define MACSEC_DEFAULT_PN_LEN 4
15 #define MACSEC_XPN_PN_LEN 8
16 
17 #define MACSEC_NUM_AN 4 /* 2 bits for the association number */
18 
19 #define MACSEC_SCI_LEN 8
20 #define MACSEC_PORT_ES (htons(0x0001))
21 
22 #define MACSEC_TCI_VERSION 0x80
23 #define MACSEC_TCI_ES      0x40 /* end station */
24 #define MACSEC_TCI_SC      0x20 /* SCI present */
25 #define MACSEC_TCI_SCB     0x10 /* epon */
26 #define MACSEC_TCI_E       0x08 /* encryption */
27 #define MACSEC_TCI_C       0x04 /* changed text */
28 #define MACSEC_AN_MASK     0x03 /* association number */
29 #define MACSEC_TCI_CONFID  (MACSEC_TCI_E | MACSEC_TCI_C)
30 
31 #define MACSEC_DEFAULT_ICV_LEN 16
32 
33 typedef u64 __bitwise sci_t;
34 typedef u32 __bitwise ssci_t;
35 
36 struct metadata_dst;
37 
38 typedef union salt {
39 	struct {
40 		u32 ssci;
41 		u64 pn;
42 	} __packed;
43 	u8 bytes[MACSEC_SALT_LEN];
44 } __packed salt_t;
45 
46 typedef union pn {
47 	struct {
48 #if defined(__LITTLE_ENDIAN_BITFIELD)
49 		u32 lower;
50 		u32 upper;
51 #elif defined(__BIG_ENDIAN_BITFIELD)
52 		u32 upper;
53 		u32 lower;
54 #else
55 #error	"Please fix <asm/byteorder.h>"
56 #endif
57 	};
58 	u64 full64;
59 } pn_t;
60 
61 /**
62  * struct macsec_key - SA key
63  * @id: user-provided key identifier
64  * @tfm: crypto struct, key storage
65  * @salt: salt used to generate IV in XPN cipher suites
66  */
67 struct macsec_key {
68 	u8 id[MACSEC_KEYID_LEN];
69 	struct crypto_aead *tfm;
70 	salt_t salt;
71 };
72 
73 struct macsec_rx_sc_stats {
74 	__u64 InOctetsValidated;
75 	__u64 InOctetsDecrypted;
76 	__u64 InPktsUnchecked;
77 	__u64 InPktsDelayed;
78 	__u64 InPktsOK;
79 	__u64 InPktsInvalid;
80 	__u64 InPktsLate;
81 	__u64 InPktsNotValid;
82 	__u64 InPktsNotUsingSA;
83 	__u64 InPktsUnusedSA;
84 };
85 
86 struct macsec_rx_sa_stats {
87 	__u32 InPktsOK;
88 	__u32 InPktsInvalid;
89 	__u32 InPktsNotValid;
90 	__u32 InPktsNotUsingSA;
91 	__u32 InPktsUnusedSA;
92 };
93 
94 struct macsec_tx_sa_stats {
95 	__u32 OutPktsProtected;
96 	__u32 OutPktsEncrypted;
97 };
98 
99 struct macsec_tx_sc_stats {
100 	__u64 OutPktsProtected;
101 	__u64 OutPktsEncrypted;
102 	__u64 OutOctetsProtected;
103 	__u64 OutOctetsEncrypted;
104 };
105 
106 struct macsec_dev_stats {
107 	__u64 OutPktsUntagged;
108 	__u64 InPktsUntagged;
109 	__u64 OutPktsTooLong;
110 	__u64 InPktsNoTag;
111 	__u64 InPktsBadTag;
112 	__u64 InPktsUnknownSCI;
113 	__u64 InPktsNoSCI;
114 	__u64 InPktsOverrun;
115 };
116 
117 /**
118  * struct macsec_rx_sa - receive secure association
119  * @active:
120  * @next_pn: packet number expected for the next packet
121  * @lock: protects next_pn manipulations
122  * @key: key structure
123  * @ssci: short secure channel identifier
124  * @stats: per-SA stats
125  */
126 struct macsec_rx_sa {
127 	struct macsec_key key;
128 	ssci_t ssci;
129 	spinlock_t lock;
130 	union {
131 		pn_t next_pn_halves;
132 		u64 next_pn;
133 	};
134 	refcount_t refcnt;
135 	bool active;
136 	struct macsec_rx_sa_stats __percpu *stats;
137 	struct macsec_rx_sc *sc;
138 	struct rcu_head rcu;
139 };
140 
141 struct pcpu_rx_sc_stats {
142 	struct macsec_rx_sc_stats stats;
143 	struct u64_stats_sync syncp;
144 };
145 
146 struct pcpu_tx_sc_stats {
147 	struct macsec_tx_sc_stats stats;
148 	struct u64_stats_sync syncp;
149 };
150 
151 /**
152  * struct macsec_rx_sc - receive secure channel
153  * @sci: secure channel identifier for this SC
154  * @active: channel is active
155  * @sa: array of secure associations
156  * @stats: per-SC stats
157  */
158 struct macsec_rx_sc {
159 	struct macsec_rx_sc __rcu *next;
160 	sci_t sci;
161 	bool active;
162 	struct macsec_rx_sa __rcu *sa[MACSEC_NUM_AN];
163 	struct pcpu_rx_sc_stats __percpu *stats;
164 	refcount_t refcnt;
165 	struct rcu_head rcu_head;
166 };
167 
168 /**
169  * struct macsec_tx_sa - transmit secure association
170  * @active:
171  * @next_pn: packet number to use for the next packet
172  * @lock: protects next_pn manipulations
173  * @key: key structure
174  * @ssci: short secure channel identifier
175  * @stats: per-SA stats
176  */
177 struct macsec_tx_sa {
178 	struct macsec_key key;
179 	ssci_t ssci;
180 	spinlock_t lock;
181 	union {
182 		pn_t next_pn_halves;
183 		u64 next_pn;
184 	};
185 	refcount_t refcnt;
186 	bool active;
187 	struct macsec_tx_sa_stats __percpu *stats;
188 	struct rcu_head rcu;
189 };
190 
191 /**
192  * struct macsec_tx_sc - transmit secure channel
193  * @active:
194  * @encoding_sa: association number of the SA currently in use
195  * @encrypt: encrypt packets on transmit, or authenticate only
196  * @send_sci: always include the SCI in the SecTAG
197  * @end_station:
198  * @scb: single copy broadcast flag
199  * @sa: array of secure associations
200  * @stats: stats for this TXSC
201  * @md_dst: MACsec offload metadata dst
202  */
203 struct macsec_tx_sc {
204 	bool active;
205 	u8 encoding_sa;
206 	bool encrypt;
207 	bool send_sci;
208 	bool end_station;
209 	bool scb;
210 	struct macsec_tx_sa __rcu *sa[MACSEC_NUM_AN];
211 	struct pcpu_tx_sc_stats __percpu *stats;
212 	struct metadata_dst *md_dst;
213 };
214 
215 /**
216  * struct macsec_secy - MACsec Security Entity
217  * @netdev: netdevice for this SecY
218  * @n_rx_sc: number of receive secure channels configured on this SecY
219  * @sci: secure channel identifier used for tx
220  * @key_len: length of keys used by the cipher suite
221  * @icv_len: length of ICV used by the cipher suite
222  * @validate_frames: validation mode
223  * @xpn: enable XPN for this SecY
224  * @operational: MAC_Operational flag
225  * @protect_frames: enable protection for this SecY
226  * @replay_protect: enable packet number checks on receive
227  * @replay_window: size of the replay window
228  * @tx_sc: transmit secure channel
229  * @rx_sc: linked list of receive secure channels
230  */
231 struct macsec_secy {
232 	struct net_device *netdev;
233 	unsigned int n_rx_sc;
234 	sci_t sci;
235 	u16 key_len;
236 	u16 icv_len;
237 	enum macsec_validation_type validate_frames;
238 	bool xpn;
239 	bool operational;
240 	bool protect_frames;
241 	bool replay_protect;
242 	u32 replay_window;
243 	struct macsec_tx_sc tx_sc;
244 	struct macsec_rx_sc __rcu *rx_sc;
245 };
246 
247 /**
248  * struct macsec_context - MACsec context for hardware offloading
249  */
250 struct macsec_context {
251 	union {
252 		struct net_device *netdev;
253 		struct phy_device *phydev;
254 	};
255 	enum macsec_offload offload;
256 
257 	struct macsec_secy *secy;
258 	struct macsec_rx_sc *rx_sc;
259 	struct {
260 		unsigned char assoc_num;
261 		u8 key[MACSEC_MAX_KEY_LEN];
262 		union {
263 			struct macsec_rx_sa *rx_sa;
264 			struct macsec_tx_sa *tx_sa;
265 		};
266 	} sa;
267 	union {
268 		struct macsec_tx_sc_stats *tx_sc_stats;
269 		struct macsec_tx_sa_stats *tx_sa_stats;
270 		struct macsec_rx_sc_stats *rx_sc_stats;
271 		struct macsec_rx_sa_stats *rx_sa_stats;
272 		struct macsec_dev_stats  *dev_stats;
273 	} stats;
274 };
275 
276 /**
277  * struct macsec_ops - MACsec offloading operations
278  */
279 struct macsec_ops {
280 	/* Device wide */
281 	int (*mdo_dev_open)(struct macsec_context *ctx);
282 	int (*mdo_dev_stop)(struct macsec_context *ctx);
283 	/* SecY */
284 	int (*mdo_add_secy)(struct macsec_context *ctx);
285 	int (*mdo_upd_secy)(struct macsec_context *ctx);
286 	int (*mdo_del_secy)(struct macsec_context *ctx);
287 	/* Security channels */
288 	int (*mdo_add_rxsc)(struct macsec_context *ctx);
289 	int (*mdo_upd_rxsc)(struct macsec_context *ctx);
290 	int (*mdo_del_rxsc)(struct macsec_context *ctx);
291 	/* Security associations */
292 	int (*mdo_add_rxsa)(struct macsec_context *ctx);
293 	int (*mdo_upd_rxsa)(struct macsec_context *ctx);
294 	int (*mdo_del_rxsa)(struct macsec_context *ctx);
295 	int (*mdo_add_txsa)(struct macsec_context *ctx);
296 	int (*mdo_upd_txsa)(struct macsec_context *ctx);
297 	int (*mdo_del_txsa)(struct macsec_context *ctx);
298 	/* Statistics */
299 	int (*mdo_get_dev_stats)(struct macsec_context *ctx);
300 	int (*mdo_get_tx_sc_stats)(struct macsec_context *ctx);
301 	int (*mdo_get_tx_sa_stats)(struct macsec_context *ctx);
302 	int (*mdo_get_rx_sc_stats)(struct macsec_context *ctx);
303 	int (*mdo_get_rx_sa_stats)(struct macsec_context *ctx);
304 };
305 
306 void macsec_pn_wrapped(struct macsec_secy *secy, struct macsec_tx_sa *tx_sa);
macsec_send_sci(const struct macsec_secy * secy)307 static inline bool macsec_send_sci(const struct macsec_secy *secy)
308 {
309 	const struct macsec_tx_sc *tx_sc = &secy->tx_sc;
310 
311 	return tx_sc->send_sci ||
312 		(secy->n_rx_sc > 1 && !tx_sc->end_station && !tx_sc->scb);
313 }
314 
315 #endif /* _NET_MACSEC_H_ */
316