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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-27 10:05:51 +0000 |
commit | 5d1646d90e1f2cceb9f0828f4b28318cd0ec7744 (patch) | |
tree | a94efe259b9009378be6d90eb30d2b019d95c194 /net/hsr/hsr_forward.c | |
parent | Initial commit. (diff) | |
download | linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.tar.xz linux-5d1646d90e1f2cceb9f0828f4b28318cd0ec7744.zip |
Adding upstream version 5.10.209.upstream/5.10.209upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'net/hsr/hsr_forward.c')
-rw-r--r-- | net/hsr/hsr_forward.c | 575 |
1 files changed, 575 insertions, 0 deletions
diff --git a/net/hsr/hsr_forward.c b/net/hsr/hsr_forward.c new file mode 100644 index 000000000..0c115d8de --- /dev/null +++ b/net/hsr/hsr_forward.c @@ -0,0 +1,575 @@ +// SPDX-License-Identifier: GPL-2.0 +/* Copyright 2011-2014 Autronica Fire and Security AS + * + * Author(s): + * 2011-2014 Arvid Brodin, arvid.brodin@alten.se + * + * Frame router for HSR and PRP. + */ + +#include "hsr_forward.h" +#include <linux/types.h> +#include <linux/skbuff.h> +#include <linux/etherdevice.h> +#include <linux/if_vlan.h> +#include "hsr_main.h" +#include "hsr_framereg.h" + +struct hsr_node; + +/* The uses I can see for these HSR supervision frames are: + * 1) Use the frames that are sent after node initialization ("HSR_TLV.Type = + * 22") to reset any sequence_nr counters belonging to that node. Useful if + * the other node's counter has been reset for some reason. + * -- + * Or not - resetting the counter and bridging the frame would create a + * loop, unfortunately. + * + * 2) Use the LifeCheck frames to detect ring breaks. I.e. if no LifeCheck + * frame is received from a particular node, we know something is wrong. + * We just register these (as with normal frames) and throw them away. + * + * 3) Allow different MAC addresses for the two slave interfaces, using the + * MacAddressA field. + */ +static bool is_supervision_frame(struct hsr_priv *hsr, struct sk_buff *skb) +{ + struct ethhdr *eth_hdr; + struct hsr_sup_tag *hsr_sup_tag; + struct hsrv1_ethhdr_sp *hsr_V1_hdr; + + WARN_ON_ONCE(!skb_mac_header_was_set(skb)); + eth_hdr = (struct ethhdr *)skb_mac_header(skb); + + /* Correct addr? */ + if (!ether_addr_equal(eth_hdr->h_dest, + hsr->sup_multicast_addr)) + return false; + + /* Correct ether type?. */ + if (!(eth_hdr->h_proto == htons(ETH_P_PRP) || + eth_hdr->h_proto == htons(ETH_P_HSR))) + return false; + + /* Get the supervision header from correct location. */ + if (eth_hdr->h_proto == htons(ETH_P_HSR)) { /* Okay HSRv1. */ + hsr_V1_hdr = (struct hsrv1_ethhdr_sp *)skb_mac_header(skb); + if (hsr_V1_hdr->hsr.encap_proto != htons(ETH_P_PRP)) + return false; + + hsr_sup_tag = &hsr_V1_hdr->hsr_sup; + } else { + hsr_sup_tag = + &((struct hsrv0_ethhdr_sp *)skb_mac_header(skb))->hsr_sup; + } + + if (hsr_sup_tag->HSR_TLV_type != HSR_TLV_ANNOUNCE && + hsr_sup_tag->HSR_TLV_type != HSR_TLV_LIFE_CHECK && + hsr_sup_tag->HSR_TLV_type != PRP_TLV_LIFE_CHECK_DD && + hsr_sup_tag->HSR_TLV_type != PRP_TLV_LIFE_CHECK_DA) + return false; + if (hsr_sup_tag->HSR_TLV_length != 12 && + hsr_sup_tag->HSR_TLV_length != sizeof(struct hsr_sup_payload)) + return false; + + return true; +} + +static struct sk_buff *create_stripped_skb_hsr(struct sk_buff *skb_in, + struct hsr_frame_info *frame) +{ + struct sk_buff *skb; + int copylen; + unsigned char *dst, *src; + + skb_pull(skb_in, HSR_HLEN); + skb = __pskb_copy(skb_in, skb_headroom(skb_in) - HSR_HLEN, GFP_ATOMIC); + skb_push(skb_in, HSR_HLEN); + if (!skb) + return NULL; + + skb_reset_mac_header(skb); + + if (skb->ip_summed == CHECKSUM_PARTIAL) + skb->csum_start -= HSR_HLEN; + + copylen = 2 * ETH_ALEN; + if (frame->is_vlan) + copylen += VLAN_HLEN; + src = skb_mac_header(skb_in); + dst = skb_mac_header(skb); + memcpy(dst, src, copylen); + + skb->protocol = eth_hdr(skb)->h_proto; + return skb; +} + +struct sk_buff *hsr_get_untagged_frame(struct hsr_frame_info *frame, + struct hsr_port *port) +{ + if (!frame->skb_std) { + if (frame->skb_hsr) + frame->skb_std = + create_stripped_skb_hsr(frame->skb_hsr, frame); + else + netdev_warn_once(port->dev, + "Unexpected frame received in hsr_get_untagged_frame()\n"); + + if (!frame->skb_std) + return NULL; + } + + return skb_clone(frame->skb_std, GFP_ATOMIC); +} + +struct sk_buff *prp_get_untagged_frame(struct hsr_frame_info *frame, + struct hsr_port *port) +{ + if (!frame->skb_std) { + if (frame->skb_prp) { + /* trim the skb by len - HSR_HLEN to exclude RCT */ + skb_trim(frame->skb_prp, + frame->skb_prp->len - HSR_HLEN); + frame->skb_std = + __pskb_copy(frame->skb_prp, + skb_headroom(frame->skb_prp), + GFP_ATOMIC); + } else { + /* Unexpected */ + WARN_ONCE(1, "%s:%d: Unexpected frame received (port_src %s)\n", + __FILE__, __LINE__, port->dev->name); + return NULL; + } + } + + return skb_clone(frame->skb_std, GFP_ATOMIC); +} + +static void prp_set_lan_id(struct prp_rct *trailer, + struct hsr_port *port) +{ + int lane_id; + + if (port->type == HSR_PT_SLAVE_A) + lane_id = 0; + else + lane_id = 1; + + /* Add net_id in the upper 3 bits of lane_id */ + lane_id |= port->hsr->net_id; + set_prp_lan_id(trailer, lane_id); +} + +/* Tailroom for PRP rct should have been created before calling this */ +static struct sk_buff *prp_fill_rct(struct sk_buff *skb, + struct hsr_frame_info *frame, + struct hsr_port *port) +{ + struct prp_rct *trailer; + int min_size = ETH_ZLEN; + int lsdu_size; + + if (!skb) + return skb; + + if (frame->is_vlan) + min_size = VLAN_ETH_ZLEN; + + if (skb_put_padto(skb, min_size)) + return NULL; + + trailer = (struct prp_rct *)skb_put(skb, HSR_HLEN); + lsdu_size = skb->len - 14; + if (frame->is_vlan) + lsdu_size -= 4; + prp_set_lan_id(trailer, port); + set_prp_LSDU_size(trailer, lsdu_size); + trailer->sequence_nr = htons(frame->sequence_nr); + trailer->PRP_suffix = htons(ETH_P_PRP); + skb->protocol = eth_hdr(skb)->h_proto; + + return skb; +} + +static void hsr_set_path_id(struct hsr_ethhdr *hsr_ethhdr, + struct hsr_port *port) +{ + int path_id; + + if (port->type == HSR_PT_SLAVE_A) + path_id = 0; + else + path_id = 1; + + set_hsr_tag_path(&hsr_ethhdr->hsr_tag, path_id); +} + +static struct sk_buff *hsr_fill_tag(struct sk_buff *skb, + struct hsr_frame_info *frame, + struct hsr_port *port, u8 proto_version) +{ + struct hsr_ethhdr *hsr_ethhdr; + int lsdu_size; + + /* pad to minimum packet size which is 60 + 6 (HSR tag) */ + if (skb_put_padto(skb, ETH_ZLEN + HSR_HLEN)) + return NULL; + + lsdu_size = skb->len - 14; + if (frame->is_vlan) + lsdu_size -= 4; + + hsr_ethhdr = (struct hsr_ethhdr *)skb_mac_header(skb); + + hsr_set_path_id(hsr_ethhdr, port); + set_hsr_tag_LSDU_size(&hsr_ethhdr->hsr_tag, lsdu_size); + hsr_ethhdr->hsr_tag.sequence_nr = htons(frame->sequence_nr); + hsr_ethhdr->hsr_tag.encap_proto = hsr_ethhdr->ethhdr.h_proto; + hsr_ethhdr->ethhdr.h_proto = htons(proto_version ? + ETH_P_HSR : ETH_P_PRP); + skb->protocol = hsr_ethhdr->ethhdr.h_proto; + + return skb; +} + +/* If the original frame was an HSR tagged frame, just clone it to be sent + * unchanged. Otherwise, create a private frame especially tagged for 'port'. + */ +struct sk_buff *hsr_create_tagged_frame(struct hsr_frame_info *frame, + struct hsr_port *port) +{ + unsigned char *dst, *src; + struct sk_buff *skb; + int movelen; + + if (frame->skb_hsr) { + struct hsr_ethhdr *hsr_ethhdr = + (struct hsr_ethhdr *)skb_mac_header(frame->skb_hsr); + + /* set the lane id properly */ + hsr_set_path_id(hsr_ethhdr, port); + return skb_clone(frame->skb_hsr, GFP_ATOMIC); + } + + /* Create the new skb with enough headroom to fit the HSR tag */ + skb = __pskb_copy(frame->skb_std, + skb_headroom(frame->skb_std) + HSR_HLEN, GFP_ATOMIC); + if (!skb) + return NULL; + skb_reset_mac_header(skb); + + if (skb->ip_summed == CHECKSUM_PARTIAL) + skb->csum_start += HSR_HLEN; + + movelen = ETH_HLEN; + if (frame->is_vlan) + movelen += VLAN_HLEN; + + src = skb_mac_header(skb); + dst = skb_push(skb, HSR_HLEN); + memmove(dst, src, movelen); + skb_reset_mac_header(skb); + + /* skb_put_padto free skb on error and hsr_fill_tag returns NULL in + * that case + */ + return hsr_fill_tag(skb, frame, port, port->hsr->prot_version); +} + +struct sk_buff *prp_create_tagged_frame(struct hsr_frame_info *frame, + struct hsr_port *port) +{ + struct sk_buff *skb; + + if (frame->skb_prp) { + struct prp_rct *trailer = skb_get_PRP_rct(frame->skb_prp); + + if (trailer) { + prp_set_lan_id(trailer, port); + } else { + WARN_ONCE(!trailer, "errored PRP skb"); + return NULL; + } + return skb_clone(frame->skb_prp, GFP_ATOMIC); + } + + skb = skb_copy_expand(frame->skb_std, 0, + skb_tailroom(frame->skb_std) + HSR_HLEN, + GFP_ATOMIC); + return prp_fill_rct(skb, frame, port); +} + +static void hsr_deliver_master(struct sk_buff *skb, struct net_device *dev, + struct hsr_node *node_src) +{ + bool was_multicast_frame; + int res, recv_len; + + was_multicast_frame = (skb->pkt_type == PACKET_MULTICAST); + hsr_addr_subst_source(node_src, skb); + skb_pull(skb, ETH_HLEN); + recv_len = skb->len; + res = netif_rx(skb); + if (res == NET_RX_DROP) { + dev->stats.rx_dropped++; + } else { + dev->stats.rx_packets++; + dev->stats.rx_bytes += recv_len; + if (was_multicast_frame) + dev->stats.multicast++; + } +} + +static int hsr_xmit(struct sk_buff *skb, struct hsr_port *port, + struct hsr_frame_info *frame) +{ + if (frame->port_rcv->type == HSR_PT_MASTER) { + hsr_addr_subst_dest(frame->node_src, skb, port); + + /* Address substitution (IEC62439-3 pp 26, 50): replace mac + * address of outgoing frame with that of the outgoing slave's. + */ + ether_addr_copy(eth_hdr(skb)->h_source, port->dev->dev_addr); + } + return dev_queue_xmit(skb); +} + +bool prp_drop_frame(struct hsr_frame_info *frame, struct hsr_port *port) +{ + return ((frame->port_rcv->type == HSR_PT_SLAVE_A && + port->type == HSR_PT_SLAVE_B) || + (frame->port_rcv->type == HSR_PT_SLAVE_B && + port->type == HSR_PT_SLAVE_A)); +} + +/* Forward the frame through all devices except: + * - Back through the receiving device + * - If it's a HSR frame: through a device where it has passed before + * - if it's a PRP frame: through another PRP slave device (no bridge) + * - To the local HSR master only if the frame is directly addressed to it, or + * a non-supervision multicast or broadcast frame. + * + * HSR slave devices should insert a HSR tag into the frame, or forward the + * frame unchanged if it's already tagged. Interlink devices should strip HSR + * tags if they're of the non-HSR type (but only after duplicate discard). The + * master device always strips HSR tags. + */ +static void hsr_forward_do(struct hsr_frame_info *frame) +{ + struct hsr_port *port; + struct sk_buff *skb; + + hsr_for_each_port(frame->port_rcv->hsr, port) { + struct hsr_priv *hsr = port->hsr; + /* Don't send frame back the way it came */ + if (port == frame->port_rcv) + continue; + + /* Don't deliver locally unless we should */ + if (port->type == HSR_PT_MASTER && !frame->is_local_dest) + continue; + + /* Deliver frames directly addressed to us to master only */ + if (port->type != HSR_PT_MASTER && frame->is_local_exclusive) + continue; + + /* Don't send frame over port where it has been sent before. + * Also fro SAN, this shouldn't be done. + */ + if (!frame->is_from_san && + hsr_register_frame_out(port, frame->node_src, + frame->sequence_nr)) + continue; + + if (frame->is_supervision && port->type == HSR_PT_MASTER) { + hsr_handle_sup_frame(frame); + continue; + } + + /* Check if frame is to be dropped. Eg. for PRP no forward + * between ports. + */ + if (hsr->proto_ops->drop_frame && + hsr->proto_ops->drop_frame(frame, port)) + continue; + + if (port->type != HSR_PT_MASTER) + skb = hsr->proto_ops->create_tagged_frame(frame, port); + else + skb = hsr->proto_ops->get_untagged_frame(frame, port); + + if (!skb) { + frame->port_rcv->dev->stats.rx_dropped++; + continue; + } + + skb->dev = port->dev; + if (port->type == HSR_PT_MASTER) + hsr_deliver_master(skb, port->dev, frame->node_src); + else + hsr_xmit(skb, port, frame); + } +} + +static void check_local_dest(struct hsr_priv *hsr, struct sk_buff *skb, + struct hsr_frame_info *frame) +{ + if (hsr_addr_is_self(hsr, eth_hdr(skb)->h_dest)) { + frame->is_local_exclusive = true; + skb->pkt_type = PACKET_HOST; + } else { + frame->is_local_exclusive = false; + } + + if (skb->pkt_type == PACKET_HOST || + skb->pkt_type == PACKET_MULTICAST || + skb->pkt_type == PACKET_BROADCAST) { + frame->is_local_dest = true; + } else { + frame->is_local_dest = false; + } +} + +static void handle_std_frame(struct sk_buff *skb, + struct hsr_frame_info *frame) +{ + struct hsr_port *port = frame->port_rcv; + struct hsr_priv *hsr = port->hsr; + + frame->skb_hsr = NULL; + frame->skb_prp = NULL; + frame->skb_std = skb; + + if (port->type != HSR_PT_MASTER) { + frame->is_from_san = true; + } else { + /* Sequence nr for the master node */ + lockdep_assert_held(&hsr->seqnr_lock); + frame->sequence_nr = hsr->sequence_nr; + hsr->sequence_nr++; + } +} + +int hsr_fill_frame_info(__be16 proto, struct sk_buff *skb, + struct hsr_frame_info *frame) +{ + struct hsr_port *port = frame->port_rcv; + struct hsr_priv *hsr = port->hsr; + + /* HSRv0 supervisory frames double as a tag so treat them as tagged. */ + if ((!hsr->prot_version && proto == htons(ETH_P_PRP)) || + proto == htons(ETH_P_HSR)) { + /* Check if skb contains hsr_ethhdr */ + if (skb->mac_len < sizeof(struct hsr_ethhdr)) + return -EINVAL; + + /* HSR tagged frame :- Data or Supervision */ + frame->skb_std = NULL; + frame->skb_prp = NULL; + frame->skb_hsr = skb; + frame->sequence_nr = hsr_get_skb_sequence_nr(skb); + return 0; + } + + /* Standard frame or PRP from master port */ + handle_std_frame(skb, frame); + + return 0; +} + +int prp_fill_frame_info(__be16 proto, struct sk_buff *skb, + struct hsr_frame_info *frame) +{ + /* Supervision frame */ + struct prp_rct *rct = skb_get_PRP_rct(skb); + + if (rct && + prp_check_lsdu_size(skb, rct, frame->is_supervision)) { + frame->skb_hsr = NULL; + frame->skb_std = NULL; + frame->skb_prp = skb; + frame->sequence_nr = prp_get_skb_sequence_nr(rct); + return 0; + } + handle_std_frame(skb, frame); + + return 0; +} + +static int fill_frame_info(struct hsr_frame_info *frame, + struct sk_buff *skb, struct hsr_port *port) +{ + struct hsr_priv *hsr = port->hsr; + struct hsr_vlan_ethhdr *vlan_hdr; + struct ethhdr *ethhdr; + __be16 proto; + int ret; + + /* Check if skb contains ethhdr */ + if (skb->mac_len < sizeof(struct ethhdr)) + return -EINVAL; + + memset(frame, 0, sizeof(*frame)); + frame->is_supervision = is_supervision_frame(port->hsr, skb); + frame->node_src = hsr_get_node(port, &hsr->node_db, skb, + frame->is_supervision, + port->type); + if (!frame->node_src) + return -1; /* Unknown node and !is_supervision, or no mem */ + + ethhdr = (struct ethhdr *)skb_mac_header(skb); + frame->is_vlan = false; + proto = ethhdr->h_proto; + + if (proto == htons(ETH_P_8021Q)) + frame->is_vlan = true; + + if (frame->is_vlan) { + vlan_hdr = (struct hsr_vlan_ethhdr *)ethhdr; + proto = vlan_hdr->vlanhdr.h_vlan_encapsulated_proto; + /* FIXME: */ + netdev_warn_once(skb->dev, "VLAN not yet supported"); + return -EINVAL; + } + + frame->is_from_san = false; + frame->port_rcv = port; + ret = hsr->proto_ops->fill_frame_info(proto, skb, frame); + if (ret) + return ret; + + check_local_dest(port->hsr, skb, frame); + + return 0; +} + +/* Must be called holding rcu read lock (because of the port parameter) */ +void hsr_forward_skb(struct sk_buff *skb, struct hsr_port *port) +{ + struct hsr_frame_info frame; + + rcu_read_lock(); + if (fill_frame_info(&frame, skb, port) < 0) + goto out_drop; + + hsr_register_frame_in(frame.node_src, port, frame.sequence_nr); + hsr_forward_do(&frame); + rcu_read_unlock(); + /* Gets called for ingress frames as well as egress from master port. + * So check and increment stats for master port only here. + */ + if (port->type == HSR_PT_MASTER) { + port->dev->stats.tx_packets++; + port->dev->stats.tx_bytes += skb->len; + } + + kfree_skb(frame.skb_hsr); + kfree_skb(frame.skb_prp); + kfree_skb(frame.skb_std); + return; + +out_drop: + rcu_read_unlock(); + port->dev->stats.tx_dropped++; + kfree_skb(skb); +} |