| // 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 = ð_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_UNKNOWN, |
| ether_setup, txqs, rxqs); |
| } |
| EXPORT_SYMBOL(alloc_etherdev_mqs); |
| |
| ssize_t sysfs_format_mac(char *buf, const unsigned char *addr, int len) |
| { |
| return scnprintf(buf, PAGE_SIZE, "%*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_fast(skb, off_eth); |
| if (skb_gro_header_hard(skb, hlen)) { |
| eh = skb_gro_header_slow(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; |
| |
| rcu_read_lock(); |
| ptype = gro_find_receive_by_type(type); |
| if (ptype == NULL) { |
| flush = 1; |
| goto out_unlock; |
| } |
| |
| 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_unlock: |
| rcu_read_unlock(); |
| 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); |
| |
| rcu_read_lock(); |
| 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)); |
| |
| rcu_read_unlock(); |
| 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(ð_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); |