net/macsec: Move some code for sharing with various drivers that implements offload

Move some MACsec infrastructure like defines and functions,
in order to avoid code duplication for future drivers which
implements MACsec offload.

Signed-off-by: Lior Nahmanson <liorna@nvidia.com>
Reviewed-by: Raed Salem <raeds@nvidia.com>
Reviewed-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Ben Ben-Ishay <benishay@nvidia.com>
Signed-off-by: Saeed Mahameed <saeedm@nvidia.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

Author: Lior Nahmanson

drivers/net/macsec.c

@@ -25,8 +25,6 @@
 
 #include <uapi/linux/if_macsec.h>
 
-#define MACSEC_SCI_LEN 8
-
 /* SecTAG length = macsec_eth_header without the optional SCI */
 #define MACSEC_TAG_LEN 6
 
@@ -47,20 +45,10 @@ struct macsec_eth_header {
 	u8 secure_channel_id[8]; /* optional */
 } __packed;
 
-#define MACSEC_TCI_VERSION 0x80
-#define MACSEC_TCI_ES      0x40 /* end station */
-#define MACSEC_TCI_SC      0x20 /* SCI present */
-#define MACSEC_TCI_SCB     0x10 /* epon */
-#define MACSEC_TCI_E       0x08 /* encryption */
-#define MACSEC_TCI_C       0x04 /* changed text */
-#define MACSEC_AN_MASK     0x03 /* association number */
-#define MACSEC_TCI_CONFID  (MACSEC_TCI_E | MACSEC_TCI_C)
-
 /* minimum secure data length deemed "not short", see IEEE 802.1AE-2006 9.7 */
 #define MIN_NON_SHORT_LEN 48
 
 #define GCM_AES_IV_LEN 12
-#define DEFAULT_ICV_LEN 16
 
 #define for_each_rxsc(secy, sc)				\
 	for (sc = rcu_dereference_bh(secy->rx_sc);	\
@@ -244,7 +232,6 @@ static struct macsec_cb *macsec_skb_cb(struct sk_buff *skb)
 	return (struct macsec_cb *)skb->cb;
 }
 
-#define MACSEC_PORT_ES (htons(0x0001))
 #define MACSEC_PORT_SCB (0x0000)
 #define MACSEC_UNDEF_SCI ((__force sci_t)0xffffffffffffffffULL)
 #define MACSEC_UNDEF_SSCI ((__force ssci_t)0xffffffff)
@@ -259,14 +246,6 @@ static struct macsec_cb *macsec_skb_cb(struct sk_buff *skb)
 #define DEFAULT_ENCODING_SA 0
 #define MACSEC_XPN_MAX_REPLAY_WINDOW (((1 << 30) - 1))
 
-static bool send_sci(const struct macsec_secy *secy)
-{
-	const struct macsec_tx_sc *tx_sc = &secy->tx_sc;
-
-	return tx_sc->send_sci ||
-		(secy->n_rx_sc > 1 && !tx_sc->end_station && !tx_sc->scb);
-}
-
 static sci_t make_sci(const u8 *addr, __be16 port)
 {
 	sci_t sci;
@@ -331,7 +310,7 @@ static void macsec_fill_sectag(struct macsec_eth_header *h,
 	/* with GCM, C/E clear for !encrypt, both set for encrypt */
 	if (tx_sc->encrypt)
 		h->tci_an |= MACSEC_TCI_CONFID;
-	else if (secy->icv_len != DEFAULT_ICV_LEN)
+	else if (secy->icv_len != MACSEC_DEFAULT_ICV_LEN)
 		h->tci_an |= MACSEC_TCI_C;
 
 	h->tci_an |= tx_sc->encoding_sa;
@@ -655,7 +634,7 @@ static struct sk_buff *macsec_encrypt(struct sk_buff *skb,
 
 	unprotected_len = skb->len;
 	eth = eth_hdr(skb);
-	sci_present = send_sci(secy);
+	sci_present = macsec_send_sci(secy);
 	hh = skb_push(skb, macsec_extra_len(sci_present));
 	memmove(hh, eth, 2 * ETH_ALEN);
 
@@ -1303,7 +1282,7 @@ static rx_handler_result_t macsec_handle_frame(struct sk_buff **pskb)
 	/* 10.6.1 if the SC is not found */
 	cbit = !!(hdr->tci_an & MACSEC_TCI_C);
 	if (!cbit)
-		macsec_finalize_skb(skb, DEFAULT_ICV_LEN,
+		macsec_finalize_skb(skb, MACSEC_DEFAULT_ICV_LEN,
 				    macsec_extra_len(macsec_skb_cb(skb)->has_sci));
 
 	list_for_each_entry_rcu(macsec, &rxd->secys, secys) {
@@ -4067,7 +4046,7 @@ static int macsec_newlink(struct net *net, struct net_device *dev,
 {
 	struct macsec_dev *macsec = macsec_priv(dev);
 	rx_handler_func_t *rx_handler;
-	u8 icv_len = DEFAULT_ICV_LEN;
+	u8 icv_len = MACSEC_DEFAULT_ICV_LEN;
 	struct net_device *real_dev;
 	int err, mtu;
 	sci_t sci;
@@ -4191,7 +4170,7 @@ static int macsec_validate_attr(struct nlattr *tb[], struct nlattr *data[],
 				struct netlink_ext_ack *extack)
 {
 	u64 csid = MACSEC_DEFAULT_CIPHER_ID;
-	u8 icv_len = DEFAULT_ICV_LEN;
+	u8 icv_len = MACSEC_DEFAULT_ICV_LEN;
 	int flag;
 	bool es, scb, sci;
 
@@ -4203,7 +4182,7 @@ static int macsec_validate_attr(struct nlattr *tb[], struct nlattr *data[],
 
 	if (data[IFLA_MACSEC_ICV_LEN]) {
 		icv_len = nla_get_u8(data[IFLA_MACSEC_ICV_LEN]);
-		if (icv_len != DEFAULT_ICV_LEN) {
+		if (icv_len != MACSEC_DEFAULT_ICV_LEN) {
 			char dummy_key[DEFAULT_SAK_LEN] = { 0 };
 			struct crypto_aead *dummy_tfm;
 

include/net/macsec.h

@@ -16,6 +16,20 @@
 
 #define MACSEC_NUM_AN 4 /* 2 bits for the association number */
 
+#define MACSEC_SCI_LEN 8
+#define MACSEC_PORT_ES (htons(0x0001))
+
+#define MACSEC_TCI_VERSION 0x80
+#define MACSEC_TCI_ES      0x40 /* end station */
+#define MACSEC_TCI_SC      0x20 /* SCI present */
+#define MACSEC_TCI_SCB     0x10 /* epon */
+#define MACSEC_TCI_E       0x08 /* encryption */
+#define MACSEC_TCI_C       0x04 /* changed text */
+#define MACSEC_AN_MASK     0x03 /* association number */
+#define MACSEC_TCI_CONFID  (MACSEC_TCI_E | MACSEC_TCI_C)
+
+#define MACSEC_DEFAULT_ICV_LEN 16
+
 typedef u64 __bitwise sci_t;
 typedef u32 __bitwise ssci_t;
 
@@ -292,5 +306,12 @@ struct macsec_ops {
 };
 
 void macsec_pn_wrapped(struct macsec_secy *secy, struct macsec_tx_sa *tx_sa);
+static inline bool macsec_send_sci(const struct macsec_secy *secy)
+{
+	const struct macsec_tx_sc *tx_sc = &secy->tx_sc;
+
+	return tx_sc->send_sci ||
+		(secy->n_rx_sc > 1 && !tx_sc->end_station && !tx_sc->scb);
+}
 
 #endif /* _NET_MACSEC_H_ */