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-rw-r--r--net/ethernet/Makefile6
-rw-r--r--net/ethernet/eth.c650
2 files changed, 656 insertions, 0 deletions
diff --git a/net/ethernet/Makefile b/net/ethernet/Makefile
new file mode 100644
index 0000000000..e03eff94e0
--- /dev/null
+++ b/net/ethernet/Makefile
@@ -0,0 +1,6 @@
+# SPDX-License-Identifier: GPL-2.0-only
+#
+# Makefile for the Linux Ethernet layer.
+#
+
+obj-y += eth.o
diff --git a/net/ethernet/eth.c b/net/ethernet/eth.c
new file mode 100644
index 0000000000..2edc8b796a
--- /dev/null
+++ b/net/ethernet/eth.c
@@ -0,0 +1,650 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * INET An implementation of the TCP/IP protocol suite for the LINUX
+ * operating system. INET is implemented using the BSD Socket
+ * interface as the means of communication with the user level.
+ *
+ * Ethernet-type device handling.
+ *
+ * Version: @(#)eth.c 1.0.7 05/25/93
+ *
+ * Authors: Ross Biro
+ * Fred N. van Kempen, <waltje@uWalt.NL.Mugnet.ORG>
+ * Mark Evans, <evansmp@uhura.aston.ac.uk>
+ * Florian La Roche, <rzsfl@rz.uni-sb.de>
+ * Alan Cox, <gw4pts@gw4pts.ampr.org>
+ *
+ * Fixes:
+ * Mr Linux : Arp problems
+ * Alan Cox : Generic queue tidyup (very tiny here)
+ * Alan Cox : eth_header ntohs should be htons
+ * Alan Cox : eth_rebuild_header missing an htons and
+ * minor other things.
+ * Tegge : Arp bug fixes.
+ * Florian : Removed many unnecessary functions, code cleanup
+ * and changes for new arp and skbuff.
+ * Alan Cox : Redid header building to reflect new format.
+ * Alan Cox : ARP only when compiled with CONFIG_INET
+ * Greg Page : 802.2 and SNAP stuff.
+ * Alan Cox : MAC layer pointers/new format.
+ * Paul Gortmaker : eth_copy_and_sum shouldn't csum padding.
+ * Alan Cox : Protect against forwarding explosions with
+ * older network drivers and IFF_ALLMULTI.
+ * Christer Weinigel : Better rebuild header message.
+ * Andrew Morton : 26Feb01: kill ether_setup() - use netdev_boot_setup().
+ */
+#include <linux/module.h>
+#include <linux/types.h>
+#include <linux/kernel.h>
+#include <linux/string.h>
+#include <linux/mm.h>
+#include <linux/socket.h>
+#include <linux/in.h>
+#include <linux/inet.h>
+#include <linux/ip.h>
+#include <linux/netdevice.h>
+#include <linux/nvmem-consumer.h>
+#include <linux/etherdevice.h>
+#include <linux/skbuff.h>
+#include <linux/errno.h>
+#include <linux/init.h>
+#include <linux/if_ether.h>
+#include <linux/of_net.h>
+#include <linux/pci.h>
+#include <linux/property.h>
+#include <net/dst.h>
+#include <net/arp.h>
+#include <net/sock.h>
+#include <net/ipv6.h>
+#include <net/ip.h>
+#include <net/dsa.h>
+#include <net/flow_dissector.h>
+#include <net/gro.h>
+#include <linux/uaccess.h>
+#include <net/pkt_sched.h>
+
+/**
+ * eth_header - create the Ethernet header
+ * @skb: buffer to alter
+ * @dev: source device
+ * @type: Ethernet type field
+ * @daddr: destination address (NULL leave destination address)
+ * @saddr: source address (NULL use device source address)
+ * @len: packet length (<= skb->len)
+ *
+ *
+ * Set the protocol type. For a packet of type ETH_P_802_3/2 we put the length
+ * in here instead.
+ */
+int eth_header(struct sk_buff *skb, struct net_device *dev,
+ unsigned short type,
+ const void *daddr, const void *saddr, unsigned int len)
+{
+ struct ethhdr *eth = skb_push(skb, ETH_HLEN);
+
+ if (type != ETH_P_802_3 && type != ETH_P_802_2)
+ eth->h_proto = htons(type);
+ else
+ eth->h_proto = htons(len);
+
+ /*
+ * Set the source hardware address.
+ */
+
+ if (!saddr)
+ saddr = dev->dev_addr;
+ memcpy(eth->h_source, saddr, ETH_ALEN);
+
+ if (daddr) {
+ memcpy(eth->h_dest, daddr, ETH_ALEN);
+ return ETH_HLEN;
+ }
+
+ /*
+ * Anyway, the loopback-device should never use this function...
+ */
+
+ if (dev->flags & (IFF_LOOPBACK | IFF_NOARP)) {
+ eth_zero_addr(eth->h_dest);
+ return ETH_HLEN;
+ }
+
+ return -ETH_HLEN;
+}
+EXPORT_SYMBOL(eth_header);
+
+/**
+ * eth_get_headlen - determine the length of header for an ethernet frame
+ * @dev: pointer to network device
+ * @data: pointer to start of frame
+ * @len: total length of frame
+ *
+ * Make a best effort attempt to pull the length for all of the headers for
+ * a given frame in a linear buffer.
+ */
+u32 eth_get_headlen(const struct net_device *dev, const void *data, u32 len)
+{
+ const unsigned int flags = FLOW_DISSECTOR_F_PARSE_1ST_FRAG;
+ const struct ethhdr *eth = (const struct ethhdr *)data;
+ struct flow_keys_basic keys;
+
+ /* this should never happen, but better safe than sorry */
+ if (unlikely(len < sizeof(*eth)))
+ return len;
+
+ /* parse any remaining L2/L3 headers, check for L4 */
+ if (!skb_flow_dissect_flow_keys_basic(dev_net(dev), NULL, &keys, data,
+ eth->h_proto, sizeof(*eth),
+ len, flags))
+ return max_t(u32, keys.control.thoff, sizeof(*eth));
+
+ /* parse for any L4 headers */
+ return min_t(u32, __skb_get_poff(NULL, data, &keys, len), len);
+}
+EXPORT_SYMBOL(eth_get_headlen);
+
+/**
+ * eth_type_trans - determine the packet's protocol ID.
+ * @skb: received socket data
+ * @dev: receiving network device
+ *
+ * The rule here is that we
+ * assume 802.3 if the type field is short enough to be a length.
+ * This is normal practice and works for any 'now in use' protocol.
+ */
+__be16 eth_type_trans(struct sk_buff *skb, struct net_device *dev)
+{
+ unsigned short _service_access_point;
+ const unsigned short *sap;
+ const struct ethhdr *eth;
+
+ skb->dev = dev;
+ skb_reset_mac_header(skb);
+
+ eth = (struct ethhdr *)skb->data;
+ skb_pull_inline(skb, ETH_HLEN);
+
+ if (unlikely(!ether_addr_equal_64bits(eth->h_dest,
+ dev->dev_addr))) {
+ if (unlikely(is_multicast_ether_addr_64bits(eth->h_dest))) {
+ if (ether_addr_equal_64bits(eth->h_dest, dev->broadcast))
+ skb->pkt_type = PACKET_BROADCAST;
+ else
+ skb->pkt_type = PACKET_MULTICAST;
+ } else {
+ skb->pkt_type = PACKET_OTHERHOST;
+ }
+ }
+
+ /*
+ * Some variants of DSA tagging don't have an ethertype field
+ * at all, so we check here whether one of those tagging
+ * variants has been configured on the receiving interface,
+ * and if so, set skb->protocol without looking at the packet.
+ */
+ if (unlikely(netdev_uses_dsa(dev)))
+ return htons(ETH_P_XDSA);
+
+ if (likely(eth_proto_is_802_3(eth->h_proto)))
+ return eth->h_proto;
+
+ /*
+ * This is a magic hack to spot IPX packets. Older Novell breaks
+ * the protocol design and runs IPX over 802.3 without an 802.2 LLC
+ * layer. We look for FFFF which isn't a used 802.2 SSAP/DSAP. This
+ * won't work for fault tolerant netware but does for the rest.
+ */
+ sap = skb_header_pointer(skb, 0, sizeof(*sap), &_service_access_point);
+ if (sap && *sap == 0xFFFF)
+ return htons(ETH_P_802_3);
+
+ /*
+ * Real 802.2 LLC
+ */
+ return htons(ETH_P_802_2);
+}
+EXPORT_SYMBOL(eth_type_trans);
+
+/**
+ * eth_header_parse - extract hardware address from packet
+ * @skb: packet to extract header from
+ * @haddr: destination buffer
+ */
+int eth_header_parse(const struct sk_buff *skb, unsigned char *haddr)
+{
+ const struct ethhdr *eth = eth_hdr(skb);
+ memcpy(haddr, eth->h_source, ETH_ALEN);
+ return ETH_ALEN;
+}
+EXPORT_SYMBOL(eth_header_parse);
+
+/**
+ * eth_header_cache - fill cache entry from neighbour
+ * @neigh: source neighbour
+ * @hh: destination cache entry
+ * @type: Ethernet type field
+ *
+ * Create an Ethernet header template from the neighbour.
+ */
+int eth_header_cache(const struct neighbour *neigh, struct hh_cache *hh, __be16 type)
+{
+ struct ethhdr *eth;
+ const struct net_device *dev = neigh->dev;
+
+ eth = (struct ethhdr *)
+ (((u8 *) hh->hh_data) + (HH_DATA_OFF(sizeof(*eth))));
+
+ if (type == htons(ETH_P_802_3))
+ return -1;
+
+ eth->h_proto = type;
+ memcpy(eth->h_source, dev->dev_addr, ETH_ALEN);
+ memcpy(eth->h_dest, neigh->ha, ETH_ALEN);
+
+ /* Pairs with READ_ONCE() in neigh_resolve_output(),
+ * neigh_hh_output() and neigh_update_hhs().
+ */
+ smp_store_release(&hh->hh_len, ETH_HLEN);
+
+ return 0;
+}
+EXPORT_SYMBOL(eth_header_cache);
+
+/**
+ * eth_header_cache_update - update cache entry
+ * @hh: destination cache entry
+ * @dev: network device
+ * @haddr: new hardware address
+ *
+ * Called by Address Resolution module to notify changes in address.
+ */
+void eth_header_cache_update(struct hh_cache *hh,
+ const struct net_device *dev,
+ const unsigned char *haddr)
+{
+ memcpy(((u8 *) hh->hh_data) + HH_DATA_OFF(sizeof(struct ethhdr)),
+ haddr, ETH_ALEN);
+}
+EXPORT_SYMBOL(eth_header_cache_update);
+
+/**
+ * eth_header_parse_protocol - extract protocol from L2 header
+ * @skb: packet to extract protocol from
+ */
+__be16 eth_header_parse_protocol(const struct sk_buff *skb)
+{
+ const struct ethhdr *eth = eth_hdr(skb);
+
+ return eth->h_proto;
+}
+EXPORT_SYMBOL(eth_header_parse_protocol);
+
+/**
+ * eth_prepare_mac_addr_change - prepare for mac change
+ * @dev: network device
+ * @p: socket address
+ */
+int eth_prepare_mac_addr_change(struct net_device *dev, void *p)
+{
+ struct sockaddr *addr = p;
+
+ if (!(dev->priv_flags & IFF_LIVE_ADDR_CHANGE) && netif_running(dev))
+ return -EBUSY;
+ if (!is_valid_ether_addr(addr->sa_data))
+ return -EADDRNOTAVAIL;
+ return 0;
+}
+EXPORT_SYMBOL(eth_prepare_mac_addr_change);
+
+/**
+ * eth_commit_mac_addr_change - commit mac change
+ * @dev: network device
+ * @p: socket address
+ */
+void eth_commit_mac_addr_change(struct net_device *dev, void *p)
+{
+ struct sockaddr *addr = p;
+
+ eth_hw_addr_set(dev, addr->sa_data);
+}
+EXPORT_SYMBOL(eth_commit_mac_addr_change);
+
+/**
+ * eth_mac_addr - set new Ethernet hardware address
+ * @dev: network device
+ * @p: socket address
+ *
+ * Change hardware address of device.
+ *
+ * This doesn't change hardware matching, so needs to be overridden
+ * for most real devices.
+ */
+int eth_mac_addr(struct net_device *dev, void *p)
+{
+ int ret;
+
+ ret = eth_prepare_mac_addr_change(dev, p);
+ if (ret < 0)
+ return ret;
+ eth_commit_mac_addr_change(dev, p);
+ return 0;
+}
+EXPORT_SYMBOL(eth_mac_addr);
+
+int eth_validate_addr(struct net_device *dev)
+{
+ if (!is_valid_ether_addr(dev->dev_addr))
+ return -EADDRNOTAVAIL;
+
+ return 0;
+}
+EXPORT_SYMBOL(eth_validate_addr);
+
+const struct header_ops eth_header_ops ____cacheline_aligned = {
+ .create = eth_header,
+ .parse = eth_header_parse,
+ .cache = eth_header_cache,
+ .cache_update = eth_header_cache_update,
+ .parse_protocol = eth_header_parse_protocol,
+};
+
+/**
+ * ether_setup - setup Ethernet network device
+ * @dev: network device
+ *
+ * Fill in the fields of the device structure with Ethernet-generic values.
+ */
+void ether_setup(struct net_device *dev)
+{
+ dev->header_ops = &eth_header_ops;
+ dev->type = ARPHRD_ETHER;
+ dev->hard_header_len = ETH_HLEN;
+ dev->min_header_len = ETH_HLEN;
+ dev->mtu = ETH_DATA_LEN;
+ dev->min_mtu = ETH_MIN_MTU;
+ dev->max_mtu = ETH_DATA_LEN;
+ dev->addr_len = ETH_ALEN;
+ dev->tx_queue_len = DEFAULT_TX_QUEUE_LEN;
+ dev->flags = IFF_BROADCAST|IFF_MULTICAST;
+ dev->priv_flags |= IFF_TX_SKB_SHARING;
+
+ eth_broadcast_addr(dev->broadcast);
+
+}
+EXPORT_SYMBOL(ether_setup);
+
+/**
+ * alloc_etherdev_mqs - Allocates and sets up an Ethernet device
+ * @sizeof_priv: Size of additional driver-private structure to be allocated
+ * for this Ethernet device
+ * @txqs: The number of TX queues this device has.
+ * @rxqs: The number of RX queues this device has.
+ *
+ * Fill in the fields of the device structure with Ethernet-generic
+ * values. Basically does everything except registering the device.
+ *
+ * Constructs a new net device, complete with a private data area of
+ * size (sizeof_priv). A 32-byte (not bit) alignment is enforced for
+ * this private data area.
+ */
+
+struct net_device *alloc_etherdev_mqs(int sizeof_priv, unsigned int txqs,
+ unsigned int rxqs)
+{
+ return alloc_netdev_mqs(sizeof_priv, "eth%d", NET_NAME_ENUM,
+ ether_setup, txqs, rxqs);
+}
+EXPORT_SYMBOL(alloc_etherdev_mqs);
+
+ssize_t sysfs_format_mac(char *buf, const unsigned char *addr, int len)
+{
+ return sysfs_emit(buf, "%*phC\n", len, addr);
+}
+EXPORT_SYMBOL(sysfs_format_mac);
+
+struct sk_buff *eth_gro_receive(struct list_head *head, struct sk_buff *skb)
+{
+ const struct packet_offload *ptype;
+ unsigned int hlen, off_eth;
+ struct sk_buff *pp = NULL;
+ struct ethhdr *eh, *eh2;
+ struct sk_buff *p;
+ __be16 type;
+ int flush = 1;
+
+ off_eth = skb_gro_offset(skb);
+ hlen = off_eth + sizeof(*eh);
+ eh = skb_gro_header(skb, hlen, off_eth);
+ if (unlikely(!eh))
+ goto out;
+
+ flush = 0;
+
+ list_for_each_entry(p, head, list) {
+ if (!NAPI_GRO_CB(p)->same_flow)
+ continue;
+
+ eh2 = (struct ethhdr *)(p->data + off_eth);
+ if (compare_ether_header(eh, eh2)) {
+ NAPI_GRO_CB(p)->same_flow = 0;
+ continue;
+ }
+ }
+
+ type = eh->h_proto;
+
+ ptype = gro_find_receive_by_type(type);
+ if (ptype == NULL) {
+ flush = 1;
+ goto out;
+ }
+
+ skb_gro_pull(skb, sizeof(*eh));
+ skb_gro_postpull_rcsum(skb, eh, sizeof(*eh));
+
+ pp = indirect_call_gro_receive_inet(ptype->callbacks.gro_receive,
+ ipv6_gro_receive, inet_gro_receive,
+ head, skb);
+
+out:
+ skb_gro_flush_final(skb, pp, flush);
+
+ return pp;
+}
+EXPORT_SYMBOL(eth_gro_receive);
+
+int eth_gro_complete(struct sk_buff *skb, int nhoff)
+{
+ struct ethhdr *eh = (struct ethhdr *)(skb->data + nhoff);
+ __be16 type = eh->h_proto;
+ struct packet_offload *ptype;
+ int err = -ENOSYS;
+
+ if (skb->encapsulation)
+ skb_set_inner_mac_header(skb, nhoff);
+
+ ptype = gro_find_complete_by_type(type);
+ if (ptype != NULL)
+ err = INDIRECT_CALL_INET(ptype->callbacks.gro_complete,
+ ipv6_gro_complete, inet_gro_complete,
+ skb, nhoff + sizeof(*eh));
+
+ return err;
+}
+EXPORT_SYMBOL(eth_gro_complete);
+
+static struct packet_offload eth_packet_offload __read_mostly = {
+ .type = cpu_to_be16(ETH_P_TEB),
+ .priority = 10,
+ .callbacks = {
+ .gro_receive = eth_gro_receive,
+ .gro_complete = eth_gro_complete,
+ },
+};
+
+static int __init eth_offload_init(void)
+{
+ dev_add_offload(&eth_packet_offload);
+
+ return 0;
+}
+
+fs_initcall(eth_offload_init);
+
+unsigned char * __weak arch_get_platform_mac_address(void)
+{
+ return NULL;
+}
+
+int eth_platform_get_mac_address(struct device *dev, u8 *mac_addr)
+{
+ unsigned char *addr;
+ int ret;
+
+ ret = of_get_mac_address(dev->of_node, mac_addr);
+ if (!ret)
+ return 0;
+
+ addr = arch_get_platform_mac_address();
+ if (!addr)
+ return -ENODEV;
+
+ ether_addr_copy(mac_addr, addr);
+
+ return 0;
+}
+EXPORT_SYMBOL(eth_platform_get_mac_address);
+
+/**
+ * platform_get_ethdev_address - Set netdev's MAC address from a given device
+ * @dev: Pointer to the device
+ * @netdev: Pointer to netdev to write the address to
+ *
+ * Wrapper around eth_platform_get_mac_address() which writes the address
+ * directly to netdev->dev_addr.
+ */
+int platform_get_ethdev_address(struct device *dev, struct net_device *netdev)
+{
+ u8 addr[ETH_ALEN] __aligned(2);
+ int ret;
+
+ ret = eth_platform_get_mac_address(dev, addr);
+ if (!ret)
+ eth_hw_addr_set(netdev, addr);
+ return ret;
+}
+EXPORT_SYMBOL(platform_get_ethdev_address);
+
+/**
+ * nvmem_get_mac_address - Obtain the MAC address from an nvmem cell named
+ * 'mac-address' associated with given device.
+ *
+ * @dev: Device with which the mac-address cell is associated.
+ * @addrbuf: Buffer to which the MAC address will be copied on success.
+ *
+ * Returns 0 on success or a negative error number on failure.
+ */
+int nvmem_get_mac_address(struct device *dev, void *addrbuf)
+{
+ struct nvmem_cell *cell;
+ const void *mac;
+ size_t len;
+
+ cell = nvmem_cell_get(dev, "mac-address");
+ if (IS_ERR(cell))
+ return PTR_ERR(cell);
+
+ mac = nvmem_cell_read(cell, &len);
+ nvmem_cell_put(cell);
+
+ if (IS_ERR(mac))
+ return PTR_ERR(mac);
+
+ if (len != ETH_ALEN || !is_valid_ether_addr(mac)) {
+ kfree(mac);
+ return -EINVAL;
+ }
+
+ ether_addr_copy(addrbuf, mac);
+ kfree(mac);
+
+ return 0;
+}
+
+static int fwnode_get_mac_addr(struct fwnode_handle *fwnode,
+ const char *name, char *addr)
+{
+ int ret;
+
+ ret = fwnode_property_read_u8_array(fwnode, name, addr, ETH_ALEN);
+ if (ret)
+ return ret;
+
+ if (!is_valid_ether_addr(addr))
+ return -EINVAL;
+ return 0;
+}
+
+/**
+ * fwnode_get_mac_address - Get the MAC from the firmware node
+ * @fwnode: Pointer to the firmware node
+ * @addr: Address of buffer to store the MAC in
+ *
+ * Search the firmware node for the best MAC address to use. 'mac-address' is
+ * checked first, because that is supposed to contain to "most recent" MAC
+ * address. If that isn't set, then 'local-mac-address' is checked next,
+ * because that is the default address. If that isn't set, then the obsolete
+ * 'address' is checked, just in case we're using an old device tree.
+ *
+ * Note that the 'address' property is supposed to contain a virtual address of
+ * the register set, but some DTS files have redefined that property to be the
+ * MAC address.
+ *
+ * All-zero MAC addresses are rejected, because those could be properties that
+ * exist in the firmware tables, but were not updated by the firmware. For
+ * example, the DTS could define 'mac-address' and 'local-mac-address', with
+ * zero MAC addresses. Some older U-Boots only initialized 'local-mac-address'.
+ * In this case, the real MAC is in 'local-mac-address', and 'mac-address'
+ * exists but is all zeros.
+ */
+int fwnode_get_mac_address(struct fwnode_handle *fwnode, char *addr)
+{
+ if (!fwnode_get_mac_addr(fwnode, "mac-address", addr) ||
+ !fwnode_get_mac_addr(fwnode, "local-mac-address", addr) ||
+ !fwnode_get_mac_addr(fwnode, "address", addr))
+ return 0;
+
+ return -ENOENT;
+}
+EXPORT_SYMBOL(fwnode_get_mac_address);
+
+/**
+ * device_get_mac_address - Get the MAC for a given device
+ * @dev: Pointer to the device
+ * @addr: Address of buffer to store the MAC in
+ */
+int device_get_mac_address(struct device *dev, char *addr)
+{
+ return fwnode_get_mac_address(dev_fwnode(dev), addr);
+}
+EXPORT_SYMBOL(device_get_mac_address);
+
+/**
+ * device_get_ethdev_address - Set netdev's MAC address from a given device
+ * @dev: Pointer to the device
+ * @netdev: Pointer to netdev to write the address to
+ *
+ * Wrapper around device_get_mac_address() which writes the address
+ * directly to netdev->dev_addr.
+ */
+int device_get_ethdev_address(struct device *dev, struct net_device *netdev)
+{
+ u8 addr[ETH_ALEN];
+ int ret;
+
+ ret = device_get_mac_address(dev, addr);
+ if (!ret)
+ eth_hw_addr_set(netdev, addr);
+ return ret;
+}
+EXPORT_SYMBOL(device_get_ethdev_address);
generated by cgit v1.2.3 (git 2.39.1) at 2024-12-03 04:39:58 +0000