macsec: Fix traffic counters/statistics

OutOctetsProtected, OutOctetsEncrypted, InOctetsValidated, and
InOctetsDecrypted were incrementing by the total number of octets in frames
instead of by the number of octets of User Data in frames.

The Controlled Port statistics ifOutOctets and ifInOctets were incrementing
by the total number of octets instead of the number of octets of the MSDUs
plus octets of the destination and source MAC addresses.

The Controlled Port statistics ifInDiscards and ifInErrors were not
incrementing each time the counters they aggregate were.

The Controlled Port statistic ifInErrors was not included in the output of
macsec_get_stats64 so the value was not present in ip commands output.

The ReceiveSA counters InPktsNotValid, InPktsNotUsingSA, and InPktsUnusedSA
were not incrementing.

Signed-off-by: Clayton Yager <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

drivers/net/macsec.c

···
 	return sa;
 }
 
+static struct macsec_rx_sa *macsec_active_rxsa_get(struct macsec_rx_sc *rx_sc)
+{
+	struct macsec_rx_sa *sa = NULL;
+	int an;
+
+	for (an = 0; an < MACSEC_NUM_AN; an++)	{
+		sa = macsec_rxsa_get(rx_sc->sa[an]);
+		if (sa)
+			break;
+	}
+	return sa;
+}
+
 static void free_rx_sc_rcu(struct rcu_head *head)
 {
 	struct macsec_rx_sc *rx_sc = container_of(head, struct macsec_rx_sc, rcu_head);
···
 	skb->protocol = eth_hdr(skb)->h_proto;
 }
 
+static unsigned int macsec_msdu_len(struct sk_buff *skb)
+{
+	struct macsec_dev *macsec = macsec_priv(skb->dev);
+	struct macsec_secy *secy = &macsec->secy;
+	bool sci_present = macsec_skb_cb(skb)->has_sci;
+
+	return skb->len - macsec_hdr_len(sci_present) - secy->icv_len;
+}
+
 static void macsec_count_tx(struct sk_buff *skb, struct macsec_tx_sc *tx_sc,
 			    struct macsec_tx_sa *tx_sa)
 {
+	unsigned int msdu_len = macsec_msdu_len(skb);
 	struct pcpu_tx_sc_stats *txsc_stats = this_cpu_ptr(tx_sc->stats);
 
 	u64_stats_update_begin(&txsc_stats->syncp);
 	if (tx_sc->encrypt) {
-		txsc_stats->stats.OutOctetsEncrypted += skb->len;
+		txsc_stats->stats.OutOctetsEncrypted += msdu_len;
 		txsc_stats->stats.OutPktsEncrypted++;
 		this_cpu_inc(tx_sa->stats->OutPktsEncrypted);
 	} else {
-		txsc_stats->stats.OutOctetsProtected += skb->len;
+		txsc_stats->stats.OutOctetsProtected += msdu_len;
 		txsc_stats->stats.OutPktsProtected++;
 		this_cpu_inc(tx_sa->stats->OutPktsProtected);
 	}
···
 	aead_request_free(macsec_skb_cb(skb)->req);
 
 	rcu_read_lock_bh();
-	macsec_encrypt_finish(skb, dev);
 	macsec_count_tx(skb, &macsec->secy.tx_sc, macsec_skb_cb(skb)->tx_sa);
-	len = skb->len;
+	/* packet is encrypted/protected so tx_bytes must be calculated */
+	len = macsec_msdu_len(skb) + 2 * ETH_ALEN;
+	macsec_encrypt_finish(skb, dev);
 	ret = dev_queue_xmit(skb);
 	count_tx(dev, ret, len);
 	rcu_read_unlock_bh();
···
 
 	macsec_skb_cb(skb)->req = req;
 	macsec_skb_cb(skb)->tx_sa = tx_sa;
+	macsec_skb_cb(skb)->has_sci = sci_present;
 	aead_request_set_callback(req, 0, macsec_encrypt_done, skb);
 
 	dev_hold(skb->dev);
···
 		u64_stats_update_begin(&rxsc_stats->syncp);
 		rxsc_stats->stats.InPktsLate++;
 		u64_stats_update_end(&rxsc_stats->syncp);
+		secy->netdev->stats.rx_dropped++;
 		return false;
 	}
 
 	if (secy->validate_frames != MACSEC_VALIDATE_DISABLED) {
+		unsigned int msdu_len = macsec_msdu_len(skb);
 		u64_stats_update_begin(&rxsc_stats->syncp);
 		if (hdr->tci_an & MACSEC_TCI_E)
-			rxsc_stats->stats.InOctetsDecrypted += skb->len;
+			rxsc_stats->stats.InOctetsDecrypted += msdu_len;
 		else
-			rxsc_stats->stats.InOctetsValidated += skb->len;
+			rxsc_stats->stats.InOctetsValidated += msdu_len;
 		u64_stats_update_end(&rxsc_stats->syncp);
 	}
 
···
 			u64_stats_update_begin(&rxsc_stats->syncp);
 			rxsc_stats->stats.InPktsNotValid++;
 			u64_stats_update_end(&rxsc_stats->syncp);
+			this_cpu_inc(rx_sa->stats->InPktsNotValid);
+			secy->netdev->stats.rx_errors++;
 			return false;
 		}
 
···
 
 	macsec_finalize_skb(skb, macsec->secy.icv_len,
 			    macsec_extra_len(macsec_skb_cb(skb)->has_sci));
+	len = skb->len;
 	macsec_reset_skb(skb, macsec->secy.netdev);
 
-	len = skb->len;
 	if (gro_cells_receive(&macsec->gro_cells, skb) == NET_RX_SUCCESS)
 		count_rx(dev, len);
 
···
 			u64_stats_update_begin(&secy_stats->syncp);
 			secy_stats->stats.InPktsNoTag++;
 			u64_stats_update_end(&secy_stats->syncp);
+			macsec->secy.netdev->stats.rx_dropped++;
 			continue;
 		}
 
···
 		u64_stats_update_begin(&secy_stats->syncp);
 		secy_stats->stats.InPktsBadTag++;
 		u64_stats_update_end(&secy_stats->syncp);
+		secy->netdev->stats.rx_errors++;
 		goto drop_nosa;
 	}
 
···
 		/* If validateFrames is Strict or the C bit in the
 		 * SecTAG is set, discard
 		 */
+		struct macsec_rx_sa *active_rx_sa = macsec_active_rxsa_get(rx_sc);
 		if (hdr->tci_an & MACSEC_TCI_C ||
 		    secy->validate_frames == MACSEC_VALIDATE_STRICT) {
 			u64_stats_update_begin(&rxsc_stats->syncp);
 			rxsc_stats->stats.InPktsNotUsingSA++;
 			u64_stats_update_end(&rxsc_stats->syncp);
+			secy->netdev->stats.rx_errors++;
+			if (active_rx_sa)
+				this_cpu_inc(active_rx_sa->stats->InPktsNotUsingSA);
 			goto drop_nosa;
 		}
 
···
 		u64_stats_update_begin(&rxsc_stats->syncp);
 		rxsc_stats->stats.InPktsUnusedSA++;
 		u64_stats_update_end(&rxsc_stats->syncp);
+		if (active_rx_sa)
+			this_cpu_inc(active_rx_sa->stats->InPktsUnusedSA);
 		goto deliver;
 	}
 
···
 			u64_stats_update_begin(&rxsc_stats->syncp);
 			rxsc_stats->stats.InPktsLate++;
 			u64_stats_update_end(&rxsc_stats->syncp);
+			macsec->secy.netdev->stats.rx_dropped++;
 			goto drop;
 		}
 	}
···
 deliver:
 	macsec_finalize_skb(skb, secy->icv_len,
 			    macsec_extra_len(macsec_skb_cb(skb)->has_sci));
+	len = skb->len;
 	macsec_reset_skb(skb, secy->netdev);
 
 	if (rx_sa)
···
 	macsec_rxsc_put(rx_sc);
 
 	skb_orphan(skb);
-	len = skb->len;
 	ret = gro_cells_receive(&macsec->gro_cells, skb);
 	if (ret == NET_RX_SUCCESS)
 		count_rx(dev, len);
···
 			u64_stats_update_begin(&secy_stats->syncp);
 			secy_stats->stats.InPktsNoSCI++;
 			u64_stats_update_end(&secy_stats->syncp);
+			macsec->secy.netdev->stats.rx_errors++;
 			continue;
 		}
 
···
 		return NETDEV_TX_OK;
 	}
 
+	len = skb->len;
 	skb = macsec_encrypt(skb, dev);
 	if (IS_ERR(skb)) {
 		if (PTR_ERR(skb) != -EINPROGRESS)
···
 	macsec_count_tx(skb, &macsec->secy.tx_sc, macsec_skb_cb(skb)->tx_sa);
 
 	macsec_encrypt_finish(skb, dev);
-	len = skb->len;
 	ret = dev_queue_xmit(skb);
 	count_tx(dev, ret, len);
 	return ret;
···
 
 	s->rx_dropped = dev->stats.rx_dropped;
 	s->tx_dropped = dev->stats.tx_dropped;
+	s->rx_errors = dev->stats.rx_errors;
 }
 
 static int macsec_get_iflink(const struct net_device *dev)