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-rw-r--r--net/hsr/hsr_framereg.c640
1 files changed, 640 insertions, 0 deletions
diff --git a/net/hsr/hsr_framereg.c b/net/hsr/hsr_framereg.c
new file mode 100644
index 000000000..0b0199878
--- /dev/null
+++ b/net/hsr/hsr_framereg.c
@@ -0,0 +1,640 @@
+// SPDX-License-Identifier: GPL-2.0
+/* Copyright 2011-2014 Autronica Fire and Security AS
+ *
+ * Author(s):
+ * 2011-2014 Arvid Brodin, arvid.brodin@alten.se
+ *
+ * The HSR spec says never to forward the same frame twice on the same
+ * interface. A frame is identified by its source MAC address and its HSR
+ * sequence number. This code keeps track of senders and their sequence numbers
+ * to allow filtering of duplicate frames, and to detect HSR ring errors.
+ * Same code handles filtering of duplicates for PRP as well.
+ */
+
+#include <linux/if_ether.h>
+#include <linux/etherdevice.h>
+#include <linux/slab.h>
+#include <linux/rculist.h>
+#include "hsr_main.h"
+#include "hsr_framereg.h"
+#include "hsr_netlink.h"
+
+/* seq_nr_after(a, b) - return true if a is after (higher in sequence than) b,
+ * false otherwise.
+ */
+static bool seq_nr_after(u16 a, u16 b)
+{
+ /* Remove inconsistency where
+ * seq_nr_after(a, b) == seq_nr_before(a, b)
+ */
+ if ((int)b - a == 32768)
+ return false;
+
+ return (((s16)(b - a)) < 0);
+}
+
+#define seq_nr_before(a, b) seq_nr_after((b), (a))
+#define seq_nr_before_or_eq(a, b) (!seq_nr_after((a), (b)))
+
+bool hsr_addr_is_self(struct hsr_priv *hsr, unsigned char *addr)
+{
+ struct hsr_node *node;
+
+ node = list_first_or_null_rcu(&hsr->self_node_db, struct hsr_node,
+ mac_list);
+ if (!node) {
+ WARN_ONCE(1, "HSR: No self node\n");
+ return false;
+ }
+
+ if (ether_addr_equal(addr, node->macaddress_A))
+ return true;
+ if (ether_addr_equal(addr, node->macaddress_B))
+ return true;
+
+ return false;
+}
+
+/* Search for mac entry. Caller must hold rcu read lock.
+ */
+static struct hsr_node *find_node_by_addr_A(struct list_head *node_db,
+ const unsigned char addr[ETH_ALEN])
+{
+ struct hsr_node *node;
+
+ list_for_each_entry_rcu(node, node_db, mac_list) {
+ if (ether_addr_equal(node->macaddress_A, addr))
+ return node;
+ }
+
+ return NULL;
+}
+
+/* Helper for device init; the self_node_db is used in hsr_rcv() to recognize
+ * frames from self that's been looped over the HSR ring.
+ */
+int hsr_create_self_node(struct hsr_priv *hsr,
+ const unsigned char addr_a[ETH_ALEN],
+ const unsigned char addr_b[ETH_ALEN])
+{
+ struct list_head *self_node_db = &hsr->self_node_db;
+ struct hsr_node *node, *oldnode;
+
+ node = kmalloc(sizeof(*node), GFP_KERNEL);
+ if (!node)
+ return -ENOMEM;
+
+ ether_addr_copy(node->macaddress_A, addr_a);
+ ether_addr_copy(node->macaddress_B, addr_b);
+
+ spin_lock_bh(&hsr->list_lock);
+ oldnode = list_first_or_null_rcu(self_node_db,
+ struct hsr_node, mac_list);
+ if (oldnode) {
+ list_replace_rcu(&oldnode->mac_list, &node->mac_list);
+ spin_unlock_bh(&hsr->list_lock);
+ kfree_rcu(oldnode, rcu_head);
+ } else {
+ list_add_tail_rcu(&node->mac_list, self_node_db);
+ spin_unlock_bh(&hsr->list_lock);
+ }
+
+ return 0;
+}
+
+void hsr_del_self_node(struct hsr_priv *hsr)
+{
+ struct list_head *self_node_db = &hsr->self_node_db;
+ struct hsr_node *node;
+
+ spin_lock_bh(&hsr->list_lock);
+ node = list_first_or_null_rcu(self_node_db, struct hsr_node, mac_list);
+ if (node) {
+ list_del_rcu(&node->mac_list);
+ kfree_rcu(node, rcu_head);
+ }
+ spin_unlock_bh(&hsr->list_lock);
+}
+
+void hsr_del_nodes(struct list_head *node_db)
+{
+ struct hsr_node *node;
+ struct hsr_node *tmp;
+
+ list_for_each_entry_safe(node, tmp, node_db, mac_list)
+ kfree(node);
+}
+
+void prp_handle_san_frame(bool san, enum hsr_port_type port,
+ struct hsr_node *node)
+{
+ /* Mark if the SAN node is over LAN_A or LAN_B */
+ if (port == HSR_PT_SLAVE_A) {
+ node->san_a = true;
+ return;
+ }
+
+ if (port == HSR_PT_SLAVE_B)
+ node->san_b = true;
+}
+
+/* Allocate an hsr_node and add it to node_db. 'addr' is the node's address_A;
+ * seq_out is used to initialize filtering of outgoing duplicate frames
+ * originating from the newly added node.
+ */
+static struct hsr_node *hsr_add_node(struct hsr_priv *hsr,
+ struct list_head *node_db,
+ unsigned char addr[],
+ u16 seq_out, bool san,
+ enum hsr_port_type rx_port)
+{
+ struct hsr_node *new_node, *node;
+ unsigned long now;
+ int i;
+
+ new_node = kzalloc(sizeof(*new_node), GFP_ATOMIC);
+ if (!new_node)
+ return NULL;
+
+ ether_addr_copy(new_node->macaddress_A, addr);
+ spin_lock_init(&new_node->seq_out_lock);
+
+ /* We are only interested in time diffs here, so use current jiffies
+ * as initialization. (0 could trigger an spurious ring error warning).
+ */
+ now = jiffies;
+ for (i = 0; i < HSR_PT_PORTS; i++) {
+ new_node->time_in[i] = now;
+ new_node->time_out[i] = now;
+ }
+ for (i = 0; i < HSR_PT_PORTS; i++)
+ new_node->seq_out[i] = seq_out;
+
+ if (san && hsr->proto_ops->handle_san_frame)
+ hsr->proto_ops->handle_san_frame(san, rx_port, new_node);
+
+ spin_lock_bh(&hsr->list_lock);
+ list_for_each_entry_rcu(node, node_db, mac_list,
+ lockdep_is_held(&hsr->list_lock)) {
+ if (ether_addr_equal(node->macaddress_A, addr))
+ goto out;
+ if (ether_addr_equal(node->macaddress_B, addr))
+ goto out;
+ }
+ list_add_tail_rcu(&new_node->mac_list, node_db);
+ spin_unlock_bh(&hsr->list_lock);
+ return new_node;
+out:
+ spin_unlock_bh(&hsr->list_lock);
+ kfree(new_node);
+ return node;
+}
+
+void prp_update_san_info(struct hsr_node *node, bool is_sup)
+{
+ if (!is_sup)
+ return;
+
+ node->san_a = false;
+ node->san_b = false;
+}
+
+/* Get the hsr_node from which 'skb' was sent.
+ */
+struct hsr_node *hsr_get_node(struct hsr_port *port, struct list_head *node_db,
+ struct sk_buff *skb, bool is_sup,
+ enum hsr_port_type rx_port)
+{
+ struct hsr_priv *hsr = port->hsr;
+ struct hsr_node *node;
+ struct ethhdr *ethhdr;
+ struct prp_rct *rct;
+ bool san = false;
+ u16 seq_out;
+
+ if (!skb_mac_header_was_set(skb))
+ return NULL;
+
+ ethhdr = (struct ethhdr *)skb_mac_header(skb);
+
+ list_for_each_entry_rcu(node, node_db, mac_list) {
+ if (ether_addr_equal(node->macaddress_A, ethhdr->h_source)) {
+ if (hsr->proto_ops->update_san_info)
+ hsr->proto_ops->update_san_info(node, is_sup);
+ return node;
+ }
+ if (ether_addr_equal(node->macaddress_B, ethhdr->h_source)) {
+ if (hsr->proto_ops->update_san_info)
+ hsr->proto_ops->update_san_info(node, is_sup);
+ return node;
+ }
+ }
+
+ /* Everyone may create a node entry, connected node to a HSR/PRP
+ * device.
+ */
+ if (ethhdr->h_proto == htons(ETH_P_PRP) ||
+ ethhdr->h_proto == htons(ETH_P_HSR)) {
+ /* Use the existing sequence_nr from the tag as starting point
+ * for filtering duplicate frames.
+ */
+ seq_out = hsr_get_skb_sequence_nr(skb) - 1;
+ } else {
+ rct = skb_get_PRP_rct(skb);
+ if (rct && prp_check_lsdu_size(skb, rct, is_sup)) {
+ seq_out = prp_get_skb_sequence_nr(rct);
+ } else {
+ if (rx_port != HSR_PT_MASTER)
+ san = true;
+ seq_out = HSR_SEQNR_START;
+ }
+ }
+
+ return hsr_add_node(hsr, node_db, ethhdr->h_source, seq_out,
+ san, rx_port);
+}
+
+/* Use the Supervision frame's info about an eventual macaddress_B for merging
+ * nodes that has previously had their macaddress_B registered as a separate
+ * node.
+ */
+void hsr_handle_sup_frame(struct hsr_frame_info *frame)
+{
+ struct hsr_node *node_curr = frame->node_src;
+ struct hsr_port *port_rcv = frame->port_rcv;
+ struct hsr_priv *hsr = port_rcv->hsr;
+ struct hsr_sup_payload *hsr_sp;
+ struct hsr_sup_tlv *hsr_sup_tlv;
+ struct hsr_node *node_real;
+ struct sk_buff *skb = NULL;
+ struct list_head *node_db;
+ struct ethhdr *ethhdr;
+ int i;
+ unsigned int pull_size = 0;
+ unsigned int total_pull_size = 0;
+
+ /* Here either frame->skb_hsr or frame->skb_prp should be
+ * valid as supervision frame always will have protocol
+ * header info.
+ */
+ if (frame->skb_hsr)
+ skb = frame->skb_hsr;
+ else if (frame->skb_prp)
+ skb = frame->skb_prp;
+ else if (frame->skb_std)
+ skb = frame->skb_std;
+ if (!skb)
+ return;
+
+ /* Leave the ethernet header. */
+ pull_size = sizeof(struct ethhdr);
+ skb_pull(skb, pull_size);
+ total_pull_size += pull_size;
+
+ ethhdr = (struct ethhdr *)skb_mac_header(skb);
+
+ /* And leave the HSR tag. */
+ if (ethhdr->h_proto == htons(ETH_P_HSR)) {
+ pull_size = sizeof(struct hsr_tag);
+ skb_pull(skb, pull_size);
+ total_pull_size += pull_size;
+ }
+
+ /* And leave the HSR sup tag. */
+ pull_size = sizeof(struct hsr_sup_tag);
+ skb_pull(skb, pull_size);
+ total_pull_size += pull_size;
+
+ /* get HSR sup payload */
+ hsr_sp = (struct hsr_sup_payload *)skb->data;
+
+ /* Merge node_curr (registered on macaddress_B) into node_real */
+ node_db = &port_rcv->hsr->node_db;
+ node_real = find_node_by_addr_A(node_db, hsr_sp->macaddress_A);
+ if (!node_real)
+ /* No frame received from AddrA of this node yet */
+ node_real = hsr_add_node(hsr, node_db, hsr_sp->macaddress_A,
+ HSR_SEQNR_START - 1, true,
+ port_rcv->type);
+ if (!node_real)
+ goto done; /* No mem */
+ if (node_real == node_curr)
+ /* Node has already been merged */
+ goto done;
+
+ /* Leave the first HSR sup payload. */
+ pull_size = sizeof(struct hsr_sup_payload);
+ skb_pull(skb, pull_size);
+ total_pull_size += pull_size;
+
+ /* Get second supervision tlv */
+ hsr_sup_tlv = (struct hsr_sup_tlv *)skb->data;
+ /* And check if it is a redbox mac TLV */
+ if (hsr_sup_tlv->HSR_TLV_type == PRP_TLV_REDBOX_MAC) {
+ /* We could stop here after pushing hsr_sup_payload,
+ * or proceed and allow macaddress_B and for redboxes.
+ */
+ /* Sanity check length */
+ if (hsr_sup_tlv->HSR_TLV_length != 6)
+ goto done;
+
+ /* Leave the second HSR sup tlv. */
+ pull_size = sizeof(struct hsr_sup_tlv);
+ skb_pull(skb, pull_size);
+ total_pull_size += pull_size;
+
+ /* Get redbox mac address. */
+ hsr_sp = (struct hsr_sup_payload *)skb->data;
+
+ /* Check if redbox mac and node mac are equal. */
+ if (!ether_addr_equal(node_real->macaddress_A, hsr_sp->macaddress_A)) {
+ /* This is a redbox supervision frame for a VDAN! */
+ goto done;
+ }
+ }
+
+ ether_addr_copy(node_real->macaddress_B, ethhdr->h_source);
+ spin_lock_bh(&node_real->seq_out_lock);
+ for (i = 0; i < HSR_PT_PORTS; i++) {
+ if (!node_curr->time_in_stale[i] &&
+ time_after(node_curr->time_in[i], node_real->time_in[i])) {
+ node_real->time_in[i] = node_curr->time_in[i];
+ node_real->time_in_stale[i] =
+ node_curr->time_in_stale[i];
+ }
+ if (seq_nr_after(node_curr->seq_out[i], node_real->seq_out[i]))
+ node_real->seq_out[i] = node_curr->seq_out[i];
+ }
+ spin_unlock_bh(&node_real->seq_out_lock);
+ node_real->addr_B_port = port_rcv->type;
+
+ spin_lock_bh(&hsr->list_lock);
+ if (!node_curr->removed) {
+ list_del_rcu(&node_curr->mac_list);
+ node_curr->removed = true;
+ kfree_rcu(node_curr, rcu_head);
+ }
+ spin_unlock_bh(&hsr->list_lock);
+
+done:
+ /* Push back here */
+ skb_push(skb, total_pull_size);
+}
+
+/* 'skb' is a frame meant for this host, that is to be passed to upper layers.
+ *
+ * If the frame was sent by a node's B interface, replace the source
+ * address with that node's "official" address (macaddress_A) so that upper
+ * layers recognize where it came from.
+ */
+void hsr_addr_subst_source(struct hsr_node *node, struct sk_buff *skb)
+{
+ if (!skb_mac_header_was_set(skb)) {
+ WARN_ONCE(1, "%s: Mac header not set\n", __func__);
+ return;
+ }
+
+ memcpy(&eth_hdr(skb)->h_source, node->macaddress_A, ETH_ALEN);
+}
+
+/* 'skb' is a frame meant for another host.
+ * 'port' is the outgoing interface
+ *
+ * Substitute the target (dest) MAC address if necessary, so the it matches the
+ * recipient interface MAC address, regardless of whether that is the
+ * recipient's A or B interface.
+ * This is needed to keep the packets flowing through switches that learn on
+ * which "side" the different interfaces are.
+ */
+void hsr_addr_subst_dest(struct hsr_node *node_src, struct sk_buff *skb,
+ struct hsr_port *port)
+{
+ struct hsr_node *node_dst;
+
+ if (!skb_mac_header_was_set(skb)) {
+ WARN_ONCE(1, "%s: Mac header not set\n", __func__);
+ return;
+ }
+
+ if (!is_unicast_ether_addr(eth_hdr(skb)->h_dest))
+ return;
+
+ node_dst = find_node_by_addr_A(&port->hsr->node_db,
+ eth_hdr(skb)->h_dest);
+ if (!node_dst) {
+ if (port->hsr->prot_version != PRP_V1 && net_ratelimit())
+ netdev_err(skb->dev, "%s: Unknown node\n", __func__);
+ return;
+ }
+ if (port->type != node_dst->addr_B_port)
+ return;
+
+ if (is_valid_ether_addr(node_dst->macaddress_B))
+ ether_addr_copy(eth_hdr(skb)->h_dest, node_dst->macaddress_B);
+}
+
+void hsr_register_frame_in(struct hsr_node *node, struct hsr_port *port,
+ u16 sequence_nr)
+{
+ /* Don't register incoming frames without a valid sequence number. This
+ * ensures entries of restarted nodes gets pruned so that they can
+ * re-register and resume communications.
+ */
+ if (!(port->dev->features & NETIF_F_HW_HSR_TAG_RM) &&
+ seq_nr_before(sequence_nr, node->seq_out[port->type]))
+ return;
+
+ node->time_in[port->type] = jiffies;
+ node->time_in_stale[port->type] = false;
+}
+
+/* 'skb' is a HSR Ethernet frame (with a HSR tag inserted), with a valid
+ * ethhdr->h_source address and skb->mac_header set.
+ *
+ * Return:
+ * 1 if frame can be shown to have been sent recently on this interface,
+ * 0 otherwise, or
+ * negative error code on error
+ */
+int hsr_register_frame_out(struct hsr_port *port, struct hsr_node *node,
+ u16 sequence_nr)
+{
+ spin_lock_bh(&node->seq_out_lock);
+ if (seq_nr_before_or_eq(sequence_nr, node->seq_out[port->type]) &&
+ time_is_after_jiffies(node->time_out[port->type] +
+ msecs_to_jiffies(HSR_ENTRY_FORGET_TIME))) {
+ spin_unlock_bh(&node->seq_out_lock);
+ return 1;
+ }
+
+ node->time_out[port->type] = jiffies;
+ node->seq_out[port->type] = sequence_nr;
+ spin_unlock_bh(&node->seq_out_lock);
+ return 0;
+}
+
+static struct hsr_port *get_late_port(struct hsr_priv *hsr,
+ struct hsr_node *node)
+{
+ if (node->time_in_stale[HSR_PT_SLAVE_A])
+ return hsr_port_get_hsr(hsr, HSR_PT_SLAVE_A);
+ if (node->time_in_stale[HSR_PT_SLAVE_B])
+ return hsr_port_get_hsr(hsr, HSR_PT_SLAVE_B);
+
+ if (time_after(node->time_in[HSR_PT_SLAVE_B],
+ node->time_in[HSR_PT_SLAVE_A] +
+ msecs_to_jiffies(MAX_SLAVE_DIFF)))
+ return hsr_port_get_hsr(hsr, HSR_PT_SLAVE_A);
+ if (time_after(node->time_in[HSR_PT_SLAVE_A],
+ node->time_in[HSR_PT_SLAVE_B] +
+ msecs_to_jiffies(MAX_SLAVE_DIFF)))
+ return hsr_port_get_hsr(hsr, HSR_PT_SLAVE_B);
+
+ return NULL;
+}
+
+/* Remove stale sequence_nr records. Called by timer every
+ * HSR_LIFE_CHECK_INTERVAL (two seconds or so).
+ */
+void hsr_prune_nodes(struct timer_list *t)
+{
+ struct hsr_priv *hsr = from_timer(hsr, t, prune_timer);
+ struct hsr_node *node;
+ struct hsr_node *tmp;
+ struct hsr_port *port;
+ unsigned long timestamp;
+ unsigned long time_a, time_b;
+
+ spin_lock_bh(&hsr->list_lock);
+ list_for_each_entry_safe(node, tmp, &hsr->node_db, mac_list) {
+ /* Don't prune own node. Neither time_in[HSR_PT_SLAVE_A]
+ * nor time_in[HSR_PT_SLAVE_B], will ever be updated for
+ * the master port. Thus the master node will be repeatedly
+ * pruned leading to packet loss.
+ */
+ if (hsr_addr_is_self(hsr, node->macaddress_A))
+ continue;
+
+ /* Shorthand */
+ time_a = node->time_in[HSR_PT_SLAVE_A];
+ time_b = node->time_in[HSR_PT_SLAVE_B];
+
+ /* Check for timestamps old enough to risk wrap-around */
+ if (time_after(jiffies, time_a + MAX_JIFFY_OFFSET / 2))
+ node->time_in_stale[HSR_PT_SLAVE_A] = true;
+ if (time_after(jiffies, time_b + MAX_JIFFY_OFFSET / 2))
+ node->time_in_stale[HSR_PT_SLAVE_B] = true;
+
+ /* Get age of newest frame from node.
+ * At least one time_in is OK here; nodes get pruned long
+ * before both time_ins can get stale
+ */
+ timestamp = time_a;
+ if (node->time_in_stale[HSR_PT_SLAVE_A] ||
+ (!node->time_in_stale[HSR_PT_SLAVE_B] &&
+ time_after(time_b, time_a)))
+ timestamp = time_b;
+
+ /* Warn of ring error only as long as we get frames at all */
+ if (time_is_after_jiffies(timestamp +
+ msecs_to_jiffies(1.5 * MAX_SLAVE_DIFF))) {
+ rcu_read_lock();
+ port = get_late_port(hsr, node);
+ if (port)
+ hsr_nl_ringerror(hsr, node->macaddress_A, port);
+ rcu_read_unlock();
+ }
+
+ /* Prune old entries */
+ if (time_is_before_jiffies(timestamp +
+ msecs_to_jiffies(HSR_NODE_FORGET_TIME))) {
+ hsr_nl_nodedown(hsr, node->macaddress_A);
+ if (!node->removed) {
+ list_del_rcu(&node->mac_list);
+ node->removed = true;
+ /* Note that we need to free this entry later: */
+ kfree_rcu(node, rcu_head);
+ }
+ }
+ }
+ spin_unlock_bh(&hsr->list_lock);
+
+ /* Restart timer */
+ mod_timer(&hsr->prune_timer,
+ jiffies + msecs_to_jiffies(PRUNE_PERIOD));
+}
+
+void *hsr_get_next_node(struct hsr_priv *hsr, void *_pos,
+ unsigned char addr[ETH_ALEN])
+{
+ struct hsr_node *node;
+
+ if (!_pos) {
+ node = list_first_or_null_rcu(&hsr->node_db,
+ struct hsr_node, mac_list);
+ if (node)
+ ether_addr_copy(addr, node->macaddress_A);
+ return node;
+ }
+
+ node = _pos;
+ list_for_each_entry_continue_rcu(node, &hsr->node_db, mac_list) {
+ ether_addr_copy(addr, node->macaddress_A);
+ return node;
+ }
+
+ return NULL;
+}
+
+int hsr_get_node_data(struct hsr_priv *hsr,
+ const unsigned char *addr,
+ unsigned char addr_b[ETH_ALEN],
+ unsigned int *addr_b_ifindex,
+ int *if1_age,
+ u16 *if1_seq,
+ int *if2_age,
+ u16 *if2_seq)
+{
+ struct hsr_node *node;
+ struct hsr_port *port;
+ unsigned long tdiff;
+
+ node = find_node_by_addr_A(&hsr->node_db, addr);
+ if (!node)
+ return -ENOENT;
+
+ ether_addr_copy(addr_b, node->macaddress_B);
+
+ tdiff = jiffies - node->time_in[HSR_PT_SLAVE_A];
+ if (node->time_in_stale[HSR_PT_SLAVE_A])
+ *if1_age = INT_MAX;
+#if HZ <= MSEC_PER_SEC
+ else if (tdiff > msecs_to_jiffies(INT_MAX))
+ *if1_age = INT_MAX;
+#endif
+ else
+ *if1_age = jiffies_to_msecs(tdiff);
+
+ tdiff = jiffies - node->time_in[HSR_PT_SLAVE_B];
+ if (node->time_in_stale[HSR_PT_SLAVE_B])
+ *if2_age = INT_MAX;
+#if HZ <= MSEC_PER_SEC
+ else if (tdiff > msecs_to_jiffies(INT_MAX))
+ *if2_age = INT_MAX;
+#endif
+ else
+ *if2_age = jiffies_to_msecs(tdiff);
+
+ /* Present sequence numbers as if they were incoming on interface */
+ *if1_seq = node->seq_out[HSR_PT_SLAVE_B];
+ *if2_seq = node->seq_out[HSR_PT_SLAVE_A];
+
+ if (node->addr_B_port != HSR_PT_NONE) {
+ port = hsr_port_get_hsr(hsr, node->addr_B_port);
+ *addr_b_ifindex = port->dev->ifindex;
+ } else {
+ *addr_b_ifindex = -1;
+ }
+
+ return 0;
+}
generated by cgit v1.2.3 (git 2.39.1) at 2024-06-09 10:43:17 +0000