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net/ipv4/arp.c
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/* linux/net/ipv4/arp.c |
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* |
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* Copyright (C) 1994 by Florian La Roche * * This module implements the Address Resolution Protocol ARP (RFC 826), * which is used to convert IP addresses (or in the future maybe other * high-level addresses) into a low-level hardware address (like an Ethernet * address). * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. * * Fixes: |
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* Alan Cox : Removed the Ethernet assumptions in |
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* Florian's code |
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* Alan Cox : Fixed some small errors in the ARP |
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* logic * Alan Cox : Allow >4K in /proc * Alan Cox : Make ARP add its own protocol entry * Ross Martin : Rewrote arp_rcv() and arp_get_info() * Stephen Henson : Add AX25 support to arp_get_info() * Alan Cox : Drop data when a device is downed. * Alan Cox : Use init_timer(). * Alan Cox : Double lock fixes. * Martin Seine : Move the arphdr structure * to if_arp.h for compatibility. * with BSD based programs. * Andrew Tridgell : Added ARP netmask code and * re-arranged proxy handling. * Alan Cox : Changed to use notifiers. * Niibe Yutaka : Reply for this device or proxies only. * Alan Cox : Don't proxy across hardware types! * Jonathan Naylor : Added support for NET/ROM. * Mike Shaver : RFC1122 checks. * Jonathan Naylor : Only lookup the hardware address for * the correct hardware type. * Germano Caronni : Assorted subtle races. |
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* Craig Schlenter : Don't modify permanent entry |
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* during arp_rcv. * Russ Nelson : Tidied up a few bits. * Alexey Kuznetsov: Major changes to caching and behaviour, |
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* eg intelligent arp probing and |
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* generation * of host down events. * Alan Cox : Missing unlock in device events. * Eckes : ARP ioctl control errors. * Alexey Kuznetsov: Arp free fix. * Manuel Rodriguez: Gratuitous ARP. |
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* Jonathan Layes : Added arpd support through kerneld |
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* message queue (960314) * Mike Shaver : /proc/sys/net/ipv4/arp_* support * Mike McLagan : Routing by source * Stuart Cheshire : Metricom and grat arp fixes * *** FOR 2.1 clean this up *** * Lawrence V. Stefani: (08/12/96) Added FDDI support. |
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* Alan Cox : Took the AP1000 nasty FDDI hack and |
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* folded into the mainstream FDDI code. * Ack spit, Linus how did you allow that * one in... * Jes Sorensen : Make FDDI work again in 2.1.x and * clean up the APFDDI & gen. FDDI bits. * Alexey Kuznetsov: new arp state machine; * now it is in net/core/neighbour.c. * Krzysztof Halasa: Added Frame Relay ARP support. * Arnaldo C. Melo : convert /proc/net/arp to seq_file * Shmulik Hen: Split arp_send to arp_create and * arp_xmit so intermediate drivers like * bonding can change the skb before * sending (e.g. insert 8021q tag). * Harald Welte : convert to make use of jenkins hash |
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* Jesper D. Brouer: Proxy ARP PVLAN RFC 3069 support. |
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*/ #include <linux/module.h> #include <linux/types.h> #include <linux/string.h> #include <linux/kernel.h> |
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#include <linux/capability.h> |
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#include <linux/socket.h> #include <linux/sockios.h> #include <linux/errno.h> #include <linux/in.h> #include <linux/mm.h> #include <linux/inet.h> |
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#include <linux/inetdevice.h> |
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#include <linux/netdevice.h> #include <linux/etherdevice.h> #include <linux/fddidevice.h> #include <linux/if_arp.h> #include <linux/trdevice.h> #include <linux/skbuff.h> #include <linux/proc_fs.h> #include <linux/seq_file.h> #include <linux/stat.h> #include <linux/init.h> #include <linux/net.h> #include <linux/rcupdate.h> |
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#include <linux/slab.h> |
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#ifdef CONFIG_SYSCTL #include <linux/sysctl.h> #endif |
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#include <net/net_namespace.h> |
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#include <net/ip.h> #include <net/icmp.h> #include <net/route.h> #include <net/protocol.h> #include <net/tcp.h> #include <net/sock.h> #include <net/arp.h> |
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#include <net/ax25.h> |
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#include <net/netrom.h> |
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#include <asm/system.h> |
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#include <linux/uaccess.h> |
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#include <linux/netfilter_arp.h> /* * Interface to generic neighbour cache. */ |
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static u32 arp_hash(const void *pkey, const struct net_device *dev, __u32 *hash_rnd); |
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static int arp_constructor(struct neighbour *neigh); static void arp_solicit(struct neighbour *neigh, struct sk_buff *skb); static void arp_error_report(struct neighbour *neigh, struct sk_buff *skb); static void parp_redo(struct sk_buff *skb); |
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static const struct neigh_ops arp_generic_ops = { |
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.family = AF_INET, .solicit = arp_solicit, .error_report = arp_error_report, .output = neigh_resolve_output, .connected_output = neigh_connected_output, |
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}; |
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static const struct neigh_ops arp_hh_ops = { |
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.family = AF_INET, .solicit = arp_solicit, .error_report = arp_error_report, .output = neigh_resolve_output, .connected_output = neigh_resolve_output, |
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}; |
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static const struct neigh_ops arp_direct_ops = { |
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.family = AF_INET, |
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.output = neigh_direct_output, .connected_output = neigh_direct_output, |
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}; |
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static const struct neigh_ops arp_broken_ops = { |
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.family = AF_INET, .solicit = arp_solicit, .error_report = arp_error_report, .output = neigh_compat_output, .connected_output = neigh_compat_output, |
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}; struct neigh_table arp_tbl = { |
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.family = AF_INET, |
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.key_len = 4, .hash = arp_hash, .constructor = arp_constructor, .proxy_redo = parp_redo, .id = "arp_cache", .parms = { .tbl = &arp_tbl, .base_reachable_time = 30 * HZ, .retrans_time = 1 * HZ, .gc_staletime = 60 * HZ, .reachable_time = 30 * HZ, .delay_probe_time = 5 * HZ, |
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.queue_len_bytes = 64*1024, |
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.ucast_probes = 3, .mcast_probes = 3, .anycast_delay = 1 * HZ, .proxy_delay = (8 * HZ) / 10, .proxy_qlen = 64, .locktime = 1 * HZ, |
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}, |
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.gc_interval = 30 * HZ, .gc_thresh1 = 128, .gc_thresh2 = 512, .gc_thresh3 = 1024, |
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}; |
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EXPORT_SYMBOL(arp_tbl); |
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int arp_mc_map(__be32 addr, u8 *haddr, struct net_device *dev, int dir) |
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{ switch (dev->type) { case ARPHRD_ETHER: case ARPHRD_FDDI: case ARPHRD_IEEE802: ip_eth_mc_map(addr, haddr); |
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return 0; |
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case ARPHRD_IEEE802_TR: ip_tr_mc_map(addr, haddr); return 0; case ARPHRD_INFINIBAND: |
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ip_ib_mc_map(addr, dev->broadcast, haddr); |
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return 0; |
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case ARPHRD_IPGRE: ip_ipgre_mc_map(addr, dev->broadcast, haddr); return 0; |
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default: if (dir) { memcpy(haddr, dev->broadcast, dev->addr_len); return 0; } } return -EINVAL; } |
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static u32 arp_hash(const void *pkey, const struct net_device *dev, |
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__u32 *hash_rnd) |
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{ |
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return arp_hashfn(*(u32 *)pkey, dev, *hash_rnd); |
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} static int arp_constructor(struct neighbour *neigh) { |
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__be32 addr = *(__be32 *)neigh->primary_key; |
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struct net_device *dev = neigh->dev; struct in_device *in_dev; struct neigh_parms *parms; |
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rcu_read_lock(); |
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in_dev = __in_dev_get_rcu(dev); |
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if (in_dev == NULL) { rcu_read_unlock(); return -EINVAL; } |
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neigh->type = inet_addr_type(dev_net(dev), addr); |
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parms = in_dev->arp_parms; __neigh_parms_put(neigh->parms); neigh->parms = neigh_parms_clone(parms); rcu_read_unlock(); |
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if (!dev->header_ops) { |
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neigh->nud_state = NUD_NOARP; neigh->ops = &arp_direct_ops; |
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neigh->output = neigh_direct_output; |
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} else { /* Good devices (checked by reading texts, but only Ethernet is tested) ARPHRD_ETHER: (ethernet, apfddi) ARPHRD_FDDI: (fddi) ARPHRD_IEEE802: (tr) ARPHRD_METRICOM: (strip) ARPHRD_ARCNET: etc. etc. etc. ARPHRD_IPDDP will also work, if author repairs it. I did not it, because this driver does not work even in old paradigm. */ #if 1 /* So... these "amateur" devices are hopeless. The only thing, that I can say now: It is very sad that we need to keep ugly obsolete code to make them happy. They should be moved to more reasonable state, now they use rebuild_header INSTEAD OF hard_start_xmit!!! Besides that, they are sort of out of date (a lot of redundant clones/copies, useless in 2.1), I wonder why people believe that they work. */ switch (dev->type) { default: break; |
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case ARPHRD_ROSE: |
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#if IS_ENABLED(CONFIG_AX25) |
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case ARPHRD_AX25: |
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#if IS_ENABLED(CONFIG_NETROM) |
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case ARPHRD_NETROM: #endif neigh->ops = &arp_broken_ops; neigh->output = neigh->ops->output; return 0; |
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#else break; |
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#endif |
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} |
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#endif if (neigh->type == RTN_MULTICAST) { neigh->nud_state = NUD_NOARP; arp_mc_map(addr, neigh->ha, dev, 1); |
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} else if (dev->flags & (IFF_NOARP | IFF_LOOPBACK)) { |
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neigh->nud_state = NUD_NOARP; memcpy(neigh->ha, dev->dev_addr, dev->addr_len); |
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} else if (neigh->type == RTN_BROADCAST || (dev->flags & IFF_POINTOPOINT)) { |
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neigh->nud_state = NUD_NOARP; memcpy(neigh->ha, dev->broadcast, dev->addr_len); } |
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if (dev->header_ops->cache) |
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neigh->ops = &arp_hh_ops; else neigh->ops = &arp_generic_ops; |
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if (neigh->nud_state & NUD_VALID) |
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neigh->output = neigh->ops->connected_output; else neigh->output = neigh->ops->output; } return 0; } static void arp_error_report(struct neighbour *neigh, struct sk_buff *skb) { dst_link_failure(skb); kfree_skb(skb); } static void arp_solicit(struct neighbour *neigh, struct sk_buff *skb) { |
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__be32 saddr = 0; |
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u8 *dst_ha = NULL; struct net_device *dev = neigh->dev; |
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__be32 target = *(__be32 *)neigh->primary_key; |
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int probes = atomic_read(&neigh->probes); |
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struct in_device *in_dev; |
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rcu_read_lock(); in_dev = __in_dev_get_rcu(dev); if (!in_dev) { rcu_read_unlock(); |
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return; |
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} |
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switch (IN_DEV_ARP_ANNOUNCE(in_dev)) { default: case 0: /* By default announce any local IP */ |
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if (skb && inet_addr_type(dev_net(dev), ip_hdr(skb)->saddr) == RTN_LOCAL) |
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saddr = ip_hdr(skb)->saddr; |
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break; case 1: /* Restrict announcements of saddr in same subnet */ if (!skb) break; |
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saddr = ip_hdr(skb)->saddr; |
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if (inet_addr_type(dev_net(dev), saddr) == RTN_LOCAL) { |
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/* saddr should be known to target */ if (inet_addr_onlink(in_dev, target, saddr)) break; } saddr = 0; break; case 2: /* Avoid secondary IPs, get a primary/preferred one */ break; } |
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rcu_read_unlock(); |
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if (!saddr) saddr = inet_select_addr(dev, target, RT_SCOPE_LINK); |
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probes -= neigh->parms->ucast_probes; if (probes < 0) { if (!(neigh->nud_state & NUD_VALID)) printk(KERN_DEBUG "trying to ucast probe in NUD_INVALID "); |
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dst_ha = neigh->ha; |
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read_lock_bh(&neigh->lock); |
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} else { probes -= neigh->parms->app_probes; if (probes < 0) { |
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#ifdef CONFIG_ARPD |
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neigh_app_ns(neigh); |
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#endif |
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return; } |
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} arp_send(ARPOP_REQUEST, ETH_P_ARP, target, dev, saddr, dst_ha, dev->dev_addr, NULL); |
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if (dst_ha) read_unlock_bh(&neigh->lock); |
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} |
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static int arp_ignore(struct in_device *in_dev, __be32 sip, __be32 tip) |
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{ int scope; switch (IN_DEV_ARP_IGNORE(in_dev)) { case 0: /* Reply, the tip is already validated */ return 0; case 1: /* Reply only if tip is configured on the incoming interface */ sip = 0; scope = RT_SCOPE_HOST; break; case 2: /* * Reply only if tip is configured on the incoming interface * and is in same subnet as sip */ scope = RT_SCOPE_HOST; break; case 3: /* Do not reply for scope host addresses */ sip = 0; scope = RT_SCOPE_LINK; |
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break; case 4: /* Reserved */ case 5: case 6: case 7: return 0; case 8: /* Do not reply */ return 1; default: return 0; } |
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return !inet_confirm_addr(in_dev, sip, tip, scope); |
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} |
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static int arp_filter(__be32 sip, __be32 tip, struct net_device *dev) |
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{ |
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struct rtable *rt; |
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int flag = 0; |
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/*unsigned long now; */ |
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struct net *net = dev_net(dev); |
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rt = ip_route_output(net, sip, tip, 0, 0); |
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if (IS_ERR(rt)) |
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return 1; |
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if (rt->dst.dev != dev) { |
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NET_INC_STATS_BH(net, LINUX_MIB_ARPFILTER); |
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flag = 1; |
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} ip_rt_put(rt); return flag; } |
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/* OBSOLETE FUNCTIONS */ /* * Find an arp mapping in the cache. If not found, post a request. * * It is very UGLY routine: it DOES NOT use skb->dst->neighbour, * even if it exists. It is supposed that skb->dev was mangled * by a virtual device (eql, shaper). Nobody but broken devices * is allowed to use this function, it is scheduled to be removed. --ANK */ |
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static int arp_set_predefined(int addr_hint, unsigned char *haddr, __be32 paddr, struct net_device *dev) |
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{ switch (addr_hint) { case RTN_LOCAL: printk(KERN_DEBUG "ARP: arp called for own IP address "); memcpy(haddr, dev->dev_addr, dev->addr_len); return 1; case RTN_MULTICAST: arp_mc_map(paddr, haddr, dev, 1); return 1; case RTN_BROADCAST: memcpy(haddr, dev->broadcast, dev->addr_len); return 1; } return 0; } int arp_find(unsigned char *haddr, struct sk_buff *skb) { struct net_device *dev = skb->dev; |
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__be32 paddr; |
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struct neighbour *n; |
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if (!skb_dst(skb)) { |
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printk(KERN_DEBUG "arp_find is called with dst==NULL "); kfree_skb(skb); return 1; } |
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paddr = skb_rtable(skb)->rt_gateway; |
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if (arp_set_predefined(inet_addr_type(dev_net(dev), paddr), haddr, paddr, dev)) |
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return 0; n = __neigh_lookup(&arp_tbl, &paddr, dev, 1); if (n) { n->used = jiffies; |
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if (n->nud_state & NUD_VALID || neigh_event_send(n, skb) == 0) { neigh_ha_snapshot(haddr, n, dev); |
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neigh_release(n); return 0; } neigh_release(n); } else kfree_skb(skb); return 1; } |
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EXPORT_SYMBOL(arp_find); |
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/* END OF OBSOLETE FUNCTIONS */ |
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/* * Check if we can use proxy ARP for this path */ |
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static inline int arp_fwd_proxy(struct in_device *in_dev, struct net_device *dev, struct rtable *rt) |
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{ struct in_device *out_dev; int imi, omi = -1; |
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if (rt->dst.dev == dev) |
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return 0; |
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if (!IN_DEV_PROXY_ARP(in_dev)) return 0; |
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imi = IN_DEV_MEDIUM_ID(in_dev); if (imi == 0) |
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return 1; if (imi == -1) return 0; /* place to check for proxy_arp for routes */ |
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out_dev = __in_dev_get_rcu(rt->dst.dev); |
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if (out_dev) |
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omi = IN_DEV_MEDIUM_ID(out_dev); |
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return omi != imi && omi != -1; |
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} /* |
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|
519 520 521 522 523 524 525 526 527 528 529 530 531 532 533 534 535 536 537 538 539 540 541 |
* Check for RFC3069 proxy arp private VLAN (allow to send back to same dev) * * RFC3069 supports proxy arp replies back to the same interface. This * is done to support (ethernet) switch features, like RFC 3069, where * the individual ports are not allowed to communicate with each * other, BUT they are allowed to talk to the upstream router. As * described in RFC 3069, it is possible to allow these hosts to * communicate through the upstream router, by proxy_arp'ing. * * RFC 3069: "VLAN Aggregation for Efficient IP Address Allocation" * * This technology is known by different names: * In RFC 3069 it is called VLAN Aggregation. * Cisco and Allied Telesyn call it Private VLAN. * Hewlett-Packard call it Source-Port filtering or port-isolation. * Ericsson call it MAC-Forced Forwarding (RFC Draft). * */ static inline int arp_fwd_pvlan(struct in_device *in_dev, struct net_device *dev, struct rtable *rt, __be32 sip, __be32 tip) { /* Private VLAN is only concerned about the same ethernet segment */ |
d8d1f30b9
|
542 |
if (rt->dst.dev != dev) |
65324144b
|
543 544 545 546 547 548 549 550 551 552 553 554 555 |
return 0; /* Don't reply on self probes (often done by windowz boxes)*/ if (sip == tip) return 0; if (IN_DEV_PROXY_ARP_PVLAN(in_dev)) return 1; else return 0; } /* |
1da177e4c
|
556 557 558 559 560 561 562 |
* Interface to link layer: send routine and receive handler. */ /* * Create an arp packet. If (dest_hw == NULL), we create a broadcast * message. */ |
ed9bad06e
|
563 564 |
struct sk_buff *arp_create(int type, int ptype, __be32 dest_ip, struct net_device *dev, __be32 src_ip, |
abfdf1c48
|
565 566 567 |
const unsigned char *dest_hw, const unsigned char *src_hw, const unsigned char *target_hw) |
1da177e4c
|
568 569 570 571 |
{ struct sk_buff *skb; struct arphdr *arp; unsigned char *arp_ptr; |
660882432
|
572 573 |
int hlen = LL_RESERVED_SPACE(dev); int tlen = dev->needed_tailroom; |
1da177e4c
|
574 575 576 577 |
/* * Allocate a buffer */ |
e905a9eda
|
578 |
|
660882432
|
579 |
skb = alloc_skb(arp_hdr_len(dev) + hlen + tlen, GFP_ATOMIC); |
1da177e4c
|
580 581 |
if (skb == NULL) return NULL; |
660882432
|
582 |
skb_reserve(skb, hlen); |
c1d2bbe1c
|
583 |
skb_reset_network_header(skb); |
988b70507
|
584 |
arp = (struct arphdr *) skb_put(skb, arp_hdr_len(dev)); |
1da177e4c
|
585 586 587 588 589 590 591 592 593 594 |
skb->dev = dev; skb->protocol = htons(ETH_P_ARP); if (src_hw == NULL) src_hw = dev->dev_addr; if (dest_hw == NULL) dest_hw = dev->broadcast; /* * Fill the device header for the ARP frame */ |
0c4e85813
|
595 |
if (dev_hard_header(skb, dev, ptype, dest_hw, src_hw, skb->len) < 0) |
1da177e4c
|
596 597 598 599 600 601 602 603 604 605 606 607 608 609 610 611 612 |
goto out; /* * Fill out the arp protocol part. * * The arp hardware type should match the device type, except for FDDI, * which (according to RFC 1390) should always equal 1 (Ethernet). */ /* * Exceptions everywhere. AX.25 uses the AX.25 PID value not the * DIX code for the protocol. Make these device structure fields. */ switch (dev->type) { default: arp->ar_hrd = htons(dev->type); arp->ar_pro = htons(ETH_P_IP); break; |
40e4783ee
|
613 |
#if IS_ENABLED(CONFIG_AX25) |
1da177e4c
|
614 615 616 617 |
case ARPHRD_AX25: arp->ar_hrd = htons(ARPHRD_AX25); arp->ar_pro = htons(AX25_P_IP); break; |
40e4783ee
|
618 |
#if IS_ENABLED(CONFIG_NETROM) |
1da177e4c
|
619 620 621 622 623 624 |
case ARPHRD_NETROM: arp->ar_hrd = htons(ARPHRD_NETROM); arp->ar_pro = htons(AX25_P_IP); break; #endif #endif |
40e4783ee
|
625 |
#if IS_ENABLED(CONFIG_FDDI) |
1da177e4c
|
626 627 628 629 630 |
case ARPHRD_FDDI: arp->ar_hrd = htons(ARPHRD_ETHER); arp->ar_pro = htons(ETH_P_IP); break; #endif |
40e4783ee
|
631 |
#if IS_ENABLED(CONFIG_TR) |
1da177e4c
|
632 633 634 635 636 637 638 639 640 641 |
case ARPHRD_IEEE802_TR: arp->ar_hrd = htons(ARPHRD_IEEE802); arp->ar_pro = htons(ETH_P_IP); break; #endif } arp->ar_hln = dev->addr_len; arp->ar_pln = 4; arp->ar_op = htons(type); |
deffd7775
|
642 |
arp_ptr = (unsigned char *)(arp + 1); |
1da177e4c
|
643 644 |
memcpy(arp_ptr, src_hw, dev->addr_len); |
f4cca7ffb
|
645 646 647 |
arp_ptr += dev->addr_len; memcpy(arp_ptr, &src_ip, 4); arp_ptr += 4; |
1da177e4c
|
648 649 650 651 |
if (target_hw != NULL) memcpy(arp_ptr, target_hw, dev->addr_len); else memset(arp_ptr, 0, dev->addr_len); |
f4cca7ffb
|
652 |
arp_ptr += dev->addr_len; |
1da177e4c
|
653 654 655 656 657 658 659 660 |
memcpy(arp_ptr, &dest_ip, 4); return skb; out: kfree_skb(skb); return NULL; } |
4bc2f18ba
|
661 |
EXPORT_SYMBOL(arp_create); |
1da177e4c
|
662 663 664 665 666 667 668 |
/* * Send an arp packet. */ void arp_xmit(struct sk_buff *skb) { /* Send it off, maybe filter it using firewalling first. */ |
fdc9314cb
|
669 |
NF_HOOK(NFPROTO_ARP, NF_ARP_OUT, skb, NULL, skb->dev, dev_queue_xmit); |
1da177e4c
|
670 |
} |
4bc2f18ba
|
671 |
EXPORT_SYMBOL(arp_xmit); |
1da177e4c
|
672 673 674 675 |
/* * Create and send an arp packet. */ |
ed9bad06e
|
676 677 |
void arp_send(int type, int ptype, __be32 dest_ip, struct net_device *dev, __be32 src_ip, |
abfdf1c48
|
678 679 |
const unsigned char *dest_hw, const unsigned char *src_hw, const unsigned char *target_hw) |
1da177e4c
|
680 681 682 683 684 685 |
{ struct sk_buff *skb; /* * No arp on this interface. */ |
e905a9eda
|
686 |
|
1da177e4c
|
687 688 689 690 691 |
if (dev->flags&IFF_NOARP) return; skb = arp_create(type, ptype, dest_ip, dev, src_ip, dest_hw, src_hw, target_hw); |
deffd7775
|
692 |
if (skb == NULL) |
1da177e4c
|
693 |
return; |
1da177e4c
|
694 695 696 |
arp_xmit(skb); } |
4bc2f18ba
|
697 |
EXPORT_SYMBOL(arp_send); |
1da177e4c
|
698 |
|
1da177e4c
|
699 700 701 702 703 704 705 |
/* * Process an arp request. */ static int arp_process(struct sk_buff *skb) { struct net_device *dev = skb->dev; |
faa9dcf79
|
706 |
struct in_device *in_dev = __in_dev_get_rcu(dev); |
1da177e4c
|
707 708 709 |
struct arphdr *arp; unsigned char *arp_ptr; struct rtable *rt; |
e0260fedd
|
710 |
unsigned char *sha; |
9e12bb22e
|
711 |
__be32 sip, tip; |
1da177e4c
|
712 713 714 |
u16 dev_type = dev->type; int addr_type; struct neighbour *n; |
c346dca10
|
715 |
struct net *net = dev_net(dev); |
1da177e4c
|
716 717 718 719 720 721 722 |
/* arp_rcv below verifies the ARP header and verifies the device * is ARP'able. */ if (in_dev == NULL) goto out; |
d0a92be05
|
723 |
arp = arp_hdr(skb); |
1da177e4c
|
724 725 |
switch (dev_type) { |
e905a9eda
|
726 |
default: |
1da177e4c
|
727 728 729 730 |
if (arp->ar_pro != htons(ETH_P_IP) || htons(dev_type) != arp->ar_hrd) goto out; break; |
1da177e4c
|
731 |
case ARPHRD_ETHER: |
1da177e4c
|
732 |
case ARPHRD_IEEE802_TR: |
1da177e4c
|
733 |
case ARPHRD_FDDI: |
1da177e4c
|
734 |
case ARPHRD_IEEE802: |
1da177e4c
|
735 736 737 738 739 740 741 742 743 744 745 746 747 748 |
/* * ETHERNET, Token Ring and Fibre Channel (which are IEEE 802 * devices, according to RFC 2625) devices will accept ARP * hardware types of either 1 (Ethernet) or 6 (IEEE 802.2). * This is the case also of FDDI, where the RFC 1390 says that * FDDI devices should accept ARP hardware of (1) Ethernet, * however, to be more robust, we'll accept both 1 (Ethernet) * or 6 (IEEE 802.2) */ if ((arp->ar_hrd != htons(ARPHRD_ETHER) && arp->ar_hrd != htons(ARPHRD_IEEE802)) || arp->ar_pro != htons(ETH_P_IP)) goto out; break; |
1da177e4c
|
749 750 751 752 753 |
case ARPHRD_AX25: if (arp->ar_pro != htons(AX25_P_IP) || arp->ar_hrd != htons(ARPHRD_AX25)) goto out; break; |
1da177e4c
|
754 755 756 757 758 |
case ARPHRD_NETROM: if (arp->ar_pro != htons(AX25_P_IP) || arp->ar_hrd != htons(ARPHRD_NETROM)) goto out; break; |
1da177e4c
|
759 760 761 762 763 764 765 766 767 768 769 |
} /* Understand only these message types */ if (arp->ar_op != htons(ARPOP_REPLY) && arp->ar_op != htons(ARPOP_REQUEST)) goto out; /* * Extract fields */ |
deffd7775
|
770 |
arp_ptr = (unsigned char *)(arp + 1); |
1da177e4c
|
771 772 773 774 |
sha = arp_ptr; arp_ptr += dev->addr_len; memcpy(&sip, arp_ptr, 4); arp_ptr += 4; |
1da177e4c
|
775 776 |
arp_ptr += dev->addr_len; memcpy(&tip, arp_ptr, 4); |
e905a9eda
|
777 |
/* |
1da177e4c
|
778 779 780 |
* Check for bad requests for 127.x.x.x and requests for multicast * addresses. If this is one such, delete it. */ |
f97c1e0c6
|
781 |
if (ipv4_is_loopback(tip) || ipv4_is_multicast(tip)) |
1da177e4c
|
782 783 784 785 786 787 788 789 790 791 792 793 |
goto out; /* * Special case: We must set Frame Relay source Q.922 address */ if (dev_type == ARPHRD_DLCI) sha = dev->broadcast; /* * Process entry. The idea here is we want to send a reply if it is a * request for us or if it is a request for someone else that we hold * a proxy for. We want to add an entry to our cache if it is a reply |
e905a9eda
|
794 795 796 797 |
* to us or if it is a request for our address. * (The assumption for this last is that if someone is requesting our * address, they are probably intending to talk to us, so it saves time * if we cache their address. Their address is also probably not in |
1da177e4c
|
798 |
* our cache, since ours is not in their cache.) |
e905a9eda
|
799 |
* |
1da177e4c
|
800 801 802 |
* Putting this another way, we only care about replies if they are to * us, in which case we add them to the cache. For requests, we care * about those for us and those for our proxies. We reply to both, |
e905a9eda
|
803 |
* and in the case of requests for us we add the requester to the arp |
1da177e4c
|
804 805 |
* cache. */ |
f8a68e752
|
806 807 |
/* Special case: IPv4 duplicate address detection packet (RFC2131) */ if (sip == 0) { |
1da177e4c
|
808 |
if (arp->ar_op == htons(ARPOP_REQUEST) && |
49e8a279a
|
809 |
inet_addr_type(net, tip) == RTN_LOCAL && |
9bd85e326
|
810 |
!arp_ignore(in_dev, sip, tip)) |
b4a9811c4
|
811 812 |
arp_send(ARPOP_REPLY, ETH_P_ARP, sip, dev, tip, sha, dev->dev_addr, sha); |
1da177e4c
|
813 814 815 816 |
goto out; } if (arp->ar_op == htons(ARPOP_REQUEST) && |
4a94445c9
|
817 |
ip_route_input_noref(skb, tip, sip, 0, dev) == 0) { |
1da177e4c
|
818 |
|
511c3f92a
|
819 |
rt = skb_rtable(skb); |
1da177e4c
|
820 821 822 |
addr_type = rt->rt_type; if (addr_type == RTN_LOCAL) { |
deffd7775
|
823 |
int dont_send; |
8164f1b79
|
824 |
|
deffd7775
|
825 |
dont_send = arp_ignore(in_dev, sip, tip); |
8164f1b79
|
826 |
if (!dont_send && IN_DEV_ARPFILTER(in_dev)) |
ae9c416d6
|
827 |
dont_send = arp_filter(sip, tip, dev); |
8164f1b79
|
828 829 830 |
if (!dont_send) { n = neigh_event_ns(&arp_tbl, sha, &sip, dev); if (n) { |
deffd7775
|
831 832 833 |
arp_send(ARPOP_REPLY, ETH_P_ARP, sip, dev, tip, sha, dev->dev_addr, sha); |
8164f1b79
|
834 835 |
neigh_release(n); } |
1da177e4c
|
836 837 838 |
} goto out; } else if (IN_DEV_FORWARD(in_dev)) { |
65324144b
|
839 840 841 |
if (addr_type == RTN_UNICAST && (arp_fwd_proxy(in_dev, dev, rt) || arp_fwd_pvlan(in_dev, dev, rt, sip, tip) || |
deffd7775
|
842 |
pneigh_lookup(&arp_tbl, net, &tip, dev, 0))) { |
1da177e4c
|
843 844 845 |
n = neigh_event_ns(&arp_tbl, sha, &sip, dev); if (n) neigh_release(n); |
e905a9eda
|
846 |
if (NEIGH_CB(skb)->flags & LOCALLY_ENQUEUED || |
1da177e4c
|
847 848 |
skb->pkt_type == PACKET_HOST || in_dev->arp_parms->proxy_delay == 0) { |
deffd7775
|
849 850 851 |
arp_send(ARPOP_REPLY, ETH_P_ARP, sip, dev, tip, sha, dev->dev_addr, sha); |
1da177e4c
|
852 |
} else { |
deffd7775
|
853 854 |
pneigh_enqueue(&arp_tbl, in_dev->arp_parms, skb); |
1da177e4c
|
855 856 857 858 859 860 861 862 863 864 |
return 0; } goto out; } } } /* Update our ARP tables */ n = __neigh_lookup(&arp_tbl, &sip, dev, 0); |
c346dca10
|
865 |
if (IPV4_DEVCONF_ALL(dev_net(dev), ARP_ACCEPT)) { |
abd596a4b
|
866 867 868 869 870 |
/* Unsolicited ARP is not accepted by default. It is possible, that this option should be enabled for some devices (strip is candidate) */ if (n == NULL && |
6d955180b
|
871 872 |
(arp->ar_op == htons(ARPOP_REPLY) || (arp->ar_op == htons(ARPOP_REQUEST) && tip == sip)) && |
49e8a279a
|
873 |
inet_addr_type(net, sip) == RTN_UNICAST) |
1b1ac759d
|
874 |
n = __neigh_lookup(&arp_tbl, &sip, dev, 1); |
abd596a4b
|
875 |
} |
1da177e4c
|
876 877 878 879 880 881 882 883 884 885 886 887 888 889 890 891 892 893 |
if (n) { int state = NUD_REACHABLE; int override; /* If several different ARP replies follows back-to-back, use the FIRST one. It is possible, if several proxy agents are active. Taking the first reply prevents arp trashing and chooses the fastest router. */ override = time_after(jiffies, n->updated + n->parms->locktime); /* Broadcast replies and request packets do not assert neighbour reachability. */ if (arp->ar_op != htons(ARPOP_REPLY) || skb->pkt_type != PACKET_HOST) state = NUD_STALE; |
deffd7775
|
894 895 |
neigh_update(n, sha, state, override ? NEIGH_UPDATE_F_OVERRIDE : 0); |
1da177e4c
|
896 897 898 899 |
neigh_release(n); } out: |
ead2ceb0e
|
900 |
consume_skb(skb); |
1da177e4c
|
901 902 |
return 0; } |
444fc8fc3
|
903 904 905 906 |
static void parp_redo(struct sk_buff *skb) { arp_process(skb); } |
1da177e4c
|
907 908 909 910 |
/* * Receive an arp request from the device layer. */ |
6c97e72a1
|
911 912 |
static int arp_rcv(struct sk_buff *skb, struct net_device *dev, struct packet_type *pt, struct net_device *orig_dev) |
1da177e4c
|
913 914 915 916 |
{ struct arphdr *arp; /* ARP header, plus 2 device addresses, plus 2 IP addresses. */ |
988b70507
|
917 |
if (!pskb_may_pull(skb, arp_hdr_len(dev))) |
1da177e4c
|
918 |
goto freeskb; |
d0a92be05
|
919 |
arp = arp_hdr(skb); |
1da177e4c
|
920 921 922 923 924 925 |
if (arp->ar_hln != dev->addr_len || dev->flags & IFF_NOARP || skb->pkt_type == PACKET_OTHERHOST || skb->pkt_type == PACKET_LOOPBACK || arp->ar_pln != 4) goto freeskb; |
deffd7775
|
926 927 |
skb = skb_share_check(skb, GFP_ATOMIC); if (skb == NULL) |
1da177e4c
|
928 |
goto out_of_mem; |
a61bbcf28
|
929 |
memset(NEIGH_CB(skb), 0, sizeof(struct neighbour_cb)); |
fdc9314cb
|
930 |
return NF_HOOK(NFPROTO_ARP, NF_ARP_IN, skb, dev, NULL, arp_process); |
1da177e4c
|
931 932 933 934 935 936 937 938 939 940 941 942 943 944 |
freeskb: kfree_skb(skb); out_of_mem: return 0; } /* * User level interface (ioctl) */ /* * Set (create) an ARP cache entry. */ |
32e569b72
|
945 |
static int arp_req_set_proxy(struct net *net, struct net_device *dev, int on) |
f8b33fdfa
|
946 947 |
{ if (dev == NULL) { |
586f12115
|
948 |
IPV4_DEVCONF_ALL(net, PROXY_ARP) = on; |
f8b33fdfa
|
949 950 |
return 0; } |
c506653d3
|
951 952 |
if (__in_dev_get_rtnl(dev)) { IN_DEV_CONF_SET(__in_dev_get_rtnl(dev), PROXY_ARP, on); |
f8b33fdfa
|
953 954 955 956 |
return 0; } return -ENXIO; } |
32e569b72
|
957 958 |
static int arp_req_set_public(struct net *net, struct arpreq *r, struct net_device *dev) |
43dc17011
|
959 960 961 962 963 964 965 |
{ __be32 ip = ((struct sockaddr_in *)&r->arp_pa)->sin_addr.s_addr; __be32 mask = ((struct sockaddr_in *)&r->arp_netmask)->sin_addr.s_addr; if (mask && mask != htonl(0xFFFFFFFF)) return -EINVAL; if (!dev && (r->arp_flags & ATF_COM)) { |
941666c2e
|
966 |
dev = dev_getbyhwaddr_rcu(net, r->arp_ha.sa_family, |
deffd7775
|
967 |
r->arp_ha.sa_data); |
43dc17011
|
968 969 970 971 |
if (!dev) return -ENODEV; } if (mask) { |
2db82b534
|
972 |
if (pneigh_lookup(&arp_tbl, net, &ip, dev, 1) == NULL) |
43dc17011
|
973 974 975 |
return -ENOBUFS; return 0; } |
f8b33fdfa
|
976 |
|
32e569b72
|
977 |
return arp_req_set_proxy(net, dev, 1); |
43dc17011
|
978 |
} |
32e569b72
|
979 |
static int arp_req_set(struct net *net, struct arpreq *r, |
deffd7775
|
980 |
struct net_device *dev) |
1da177e4c
|
981 |
{ |
43dc17011
|
982 |
__be32 ip; |
1da177e4c
|
983 984 |
struct neighbour *neigh; int err; |
43dc17011
|
985 |
if (r->arp_flags & ATF_PUBL) |
32e569b72
|
986 |
return arp_req_set_public(net, r, dev); |
1da177e4c
|
987 |
|
43dc17011
|
988 |
ip = ((struct sockaddr_in *)&r->arp_pa)->sin_addr.s_addr; |
1da177e4c
|
989 990 991 |
if (r->arp_flags & ATF_PERM) r->arp_flags |= ATF_COM; if (dev == NULL) { |
78fbfd8a6
|
992 |
struct rtable *rt = ip_route_output(net, ip, 0, RTO_ONLINK, 0); |
b23dd4fe4
|
993 994 995 |
if (IS_ERR(rt)) return PTR_ERR(rt); |
d8d1f30b9
|
996 |
dev = rt->dst.dev; |
1da177e4c
|
997 998 999 1000 1001 |
ip_rt_put(rt); if (!dev) return -EINVAL; } switch (dev->type) { |
40e4783ee
|
1002 |
#if IS_ENABLED(CONFIG_FDDI) |
1da177e4c
|
1003 1004 1005 1006 1007 1008 1009 1010 1011 1012 1013 1014 1015 1016 1017 1018 1019 1020 1021 1022 1023 1024 1025 1026 1027 |
case ARPHRD_FDDI: /* * According to RFC 1390, FDDI devices should accept ARP * hardware types of 1 (Ethernet). However, to be more * robust, we'll accept hardware types of either 1 (Ethernet) * or 6 (IEEE 802.2). */ if (r->arp_ha.sa_family != ARPHRD_FDDI && r->arp_ha.sa_family != ARPHRD_ETHER && r->arp_ha.sa_family != ARPHRD_IEEE802) return -EINVAL; break; #endif default: if (r->arp_ha.sa_family != dev->type) return -EINVAL; break; } neigh = __neigh_lookup_errno(&arp_tbl, &ip, dev); err = PTR_ERR(neigh); if (!IS_ERR(neigh)) { unsigned state = NUD_STALE; if (r->arp_flags & ATF_PERM) state = NUD_PERMANENT; |
deffd7775
|
1028 |
err = neigh_update(neigh, (r->arp_flags & ATF_COM) ? |
e905a9eda
|
1029 |
r->arp_ha.sa_data : NULL, state, |
deffd7775
|
1030 |
NEIGH_UPDATE_F_OVERRIDE | |
1da177e4c
|
1031 1032 1033 1034 1035 1036 1037 1038 |
NEIGH_UPDATE_F_ADMIN); neigh_release(neigh); } return err; } static unsigned arp_state_to_flags(struct neighbour *neigh) { |
1da177e4c
|
1039 |
if (neigh->nud_state&NUD_PERMANENT) |
deffd7775
|
1040 |
return ATF_PERM | ATF_COM; |
1da177e4c
|
1041 |
else if (neigh->nud_state&NUD_VALID) |
deffd7775
|
1042 1043 1044 |
return ATF_COM; else return 0; |
1da177e4c
|
1045 1046 1047 1048 1049 1050 1051 1052 |
} /* * Get an ARP cache entry. */ static int arp_req_get(struct arpreq *r, struct net_device *dev) { |
ed9bad06e
|
1053 |
__be32 ip = ((struct sockaddr_in *) &r->arp_pa)->sin_addr.s_addr; |
1da177e4c
|
1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 |
struct neighbour *neigh; int err = -ENXIO; neigh = neigh_lookup(&arp_tbl, &ip, dev); if (neigh) { read_lock_bh(&neigh->lock); memcpy(r->arp_ha.sa_data, neigh->ha, dev->addr_len); r->arp_flags = arp_state_to_flags(neigh); read_unlock_bh(&neigh->lock); r->arp_ha.sa_family = dev->type; strlcpy(r->arp_dev, dev->name, sizeof(r->arp_dev)); neigh_release(neigh); err = 0; } return err; } |
545ecdc3b
|
1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 |
int arp_invalidate(struct net_device *dev, __be32 ip) { struct neighbour *neigh = neigh_lookup(&arp_tbl, &ip, dev); int err = -ENXIO; if (neigh) { if (neigh->nud_state & ~NUD_NOARP) err = neigh_update(neigh, NULL, NUD_FAILED, NEIGH_UPDATE_F_OVERRIDE| NEIGH_UPDATE_F_ADMIN); neigh_release(neigh); } return err; } EXPORT_SYMBOL(arp_invalidate); |
32e569b72
|
1086 1087 |
static int arp_req_delete_public(struct net *net, struct arpreq *r, struct net_device *dev) |
46479b432
|
1088 1089 1090 1091 1092 |
{ __be32 ip = ((struct sockaddr_in *) &r->arp_pa)->sin_addr.s_addr; __be32 mask = ((struct sockaddr_in *)&r->arp_netmask)->sin_addr.s_addr; if (mask == htonl(0xFFFFFFFF)) |
2db82b534
|
1093 |
return pneigh_delete(&arp_tbl, net, &ip, dev); |
46479b432
|
1094 |
|
f8b33fdfa
|
1095 1096 |
if (mask) return -EINVAL; |
32e569b72
|
1097 |
return arp_req_set_proxy(net, dev, 0); |
46479b432
|
1098 |
} |
32e569b72
|
1099 |
static int arp_req_delete(struct net *net, struct arpreq *r, |
deffd7775
|
1100 |
struct net_device *dev) |
1da177e4c
|
1101 |
{ |
46479b432
|
1102 |
__be32 ip; |
1da177e4c
|
1103 |
|
46479b432
|
1104 |
if (r->arp_flags & ATF_PUBL) |
32e569b72
|
1105 |
return arp_req_delete_public(net, r, dev); |
1da177e4c
|
1106 |
|
46479b432
|
1107 |
ip = ((struct sockaddr_in *)&r->arp_pa)->sin_addr.s_addr; |
1da177e4c
|
1108 |
if (dev == NULL) { |
78fbfd8a6
|
1109 |
struct rtable *rt = ip_route_output(net, ip, 0, RTO_ONLINK, 0); |
b23dd4fe4
|
1110 1111 |
if (IS_ERR(rt)) return PTR_ERR(rt); |
d8d1f30b9
|
1112 |
dev = rt->dst.dev; |
1da177e4c
|
1113 1114 1115 1116 |
ip_rt_put(rt); if (!dev) return -EINVAL; } |
545ecdc3b
|
1117 |
return arp_invalidate(dev, ip); |
1da177e4c
|
1118 1119 1120 1121 1122 |
} /* * Handle an ARP layer I/O control request. */ |
32e569b72
|
1123 |
int arp_ioctl(struct net *net, unsigned int cmd, void __user *arg) |
1da177e4c
|
1124 1125 1126 1127 1128 1129 |
{ int err; struct arpreq r; struct net_device *dev = NULL; switch (cmd) { |
deffd7775
|
1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 |
case SIOCDARP: case SIOCSARP: if (!capable(CAP_NET_ADMIN)) return -EPERM; case SIOCGARP: err = copy_from_user(&r, arg, sizeof(struct arpreq)); if (err) return -EFAULT; break; default: return -EINVAL; |
1da177e4c
|
1141 1142 1143 1144 1145 1146 |
} if (r.arp_pa.sa_family != AF_INET) return -EPFNOSUPPORT; if (!(r.arp_flags & ATF_PUBL) && |
deffd7775
|
1147 |
(r.arp_flags & (ATF_NETMASK | ATF_DONTPUB))) |
1da177e4c
|
1148 1149 1150 1151 |
return -EINVAL; if (!(r.arp_flags & ATF_NETMASK)) ((struct sockaddr_in *)&r.arp_netmask)->sin_addr.s_addr = htonl(0xFFFFFFFFUL); |
c506653d3
|
1152 |
rtnl_lock(); |
1da177e4c
|
1153 1154 |
if (r.arp_dev[0]) { err = -ENODEV; |
c506653d3
|
1155 |
dev = __dev_get_by_name(net, r.arp_dev); |
deffd7775
|
1156 |
if (dev == NULL) |
1da177e4c
|
1157 1158 1159 1160 1161 1162 1163 1164 1165 1166 1167 1168 |
goto out; /* Mmmm... It is wrong... ARPHRD_NETROM==0 */ if (!r.arp_ha.sa_family) r.arp_ha.sa_family = dev->type; err = -EINVAL; if ((r.arp_flags & ATF_COM) && r.arp_ha.sa_family != dev->type) goto out; } else if (cmd == SIOCGARP) { err = -ENODEV; goto out; } |
132adf546
|
1169 |
switch (cmd) { |
1da177e4c
|
1170 |
case SIOCDARP: |
32e569b72
|
1171 |
err = arp_req_delete(net, &r, dev); |
1da177e4c
|
1172 1173 |
break; case SIOCSARP: |
32e569b72
|
1174 |
err = arp_req_set(net, &r, dev); |
1da177e4c
|
1175 1176 1177 |
break; case SIOCGARP: err = arp_req_get(&r, dev); |
1da177e4c
|
1178 1179 1180 |
break; } out: |
c506653d3
|
1181 |
rtnl_unlock(); |
941666c2e
|
1182 1183 |
if (cmd == SIOCGARP && !err && copy_to_user(arg, &r, sizeof(r))) err = -EFAULT; |
1da177e4c
|
1184 1185 |
return err; } |
deffd7775
|
1186 1187 |
static int arp_netdev_event(struct notifier_block *this, unsigned long event, void *ptr) |
1da177e4c
|
1188 1189 1190 1191 1192 1193 |
{ struct net_device *dev = ptr; switch (event) { case NETDEV_CHANGEADDR: neigh_changeaddr(&arp_tbl, dev); |
76e6ebfb4
|
1194 |
rt_cache_flush(dev_net(dev), 0); |
1da177e4c
|
1195 1196 1197 1198 1199 1200 1201 1202 1203 1204 1205 1206 1207 1208 1209 1210 1211 1212 1213 1214 1215 1216 1217 1218 1219 |
break; default: break; } return NOTIFY_DONE; } static struct notifier_block arp_netdev_notifier = { .notifier_call = arp_netdev_event, }; /* Note, that it is not on notifier chain. It is necessary, that this routine was called after route cache will be flushed. */ void arp_ifdown(struct net_device *dev) { neigh_ifdown(&arp_tbl, dev); } /* * Called once on startup. */ |
7546dd97d
|
1220 |
static struct packet_type arp_packet_type __read_mostly = { |
09640e636
|
1221 |
.type = cpu_to_be16(ETH_P_ARP), |
1da177e4c
|
1222 1223 1224 1225 1226 1227 1228 1229 1230 1231 1232 1233 |
.func = arp_rcv, }; static int arp_proc_init(void); void __init arp_init(void) { neigh_table_init(&arp_tbl); dev_add_pack(&arp_packet_type); arp_proc_init(); #ifdef CONFIG_SYSCTL |
54716e3be
|
1234 |
neigh_sysctl_register(NULL, &arp_tbl.parms, "ipv4", NULL); |
1da177e4c
|
1235 1236 1237 1238 1239 |
#endif register_netdevice_notifier(&arp_netdev_notifier); } #ifdef CONFIG_PROC_FS |
40e4783ee
|
1240 |
#if IS_ENABLED(CONFIG_AX25) |
1da177e4c
|
1241 1242 1243 1244 1245 1246 1247 1248 1249 1250 1251 1252 |
/* ------------------------------------------------------------------------ */ /* * ax25 -> ASCII conversion */ static char *ax2asc2(ax25_address *a, char *buf) { char c, *s; int n; for (n = 0, s = buf; n < 6; n++) { c = (a->ax25_call[n] >> 1) & 0x7F; |
deffd7775
|
1253 1254 |
if (c != ' ') *s++ = c; |
1da177e4c
|
1255 |
} |
e905a9eda
|
1256 |
|
1da177e4c
|
1257 |
*s++ = '-'; |
deffd7775
|
1258 1259 |
n = (a->ax25_call[6] >> 1) & 0x0F; if (n > 9) { |
1da177e4c
|
1260 1261 1262 |
*s++ = '1'; n -= 10; } |
e905a9eda
|
1263 |
|
1da177e4c
|
1264 1265 1266 1267 |
*s++ = n + '0'; *s++ = '\0'; if (*buf == '\0' || *buf == '-') |
deffd7775
|
1268 |
return "*"; |
1da177e4c
|
1269 1270 |
return buf; |
1da177e4c
|
1271 1272 1273 1274 1275 1276 1277 1278 1279 |
} #endif /* CONFIG_AX25 */ #define HBUFFERLEN 30 static void arp_format_neigh_entry(struct seq_file *seq, struct neighbour *n) { char hbuffer[HBUFFERLEN]; |
1da177e4c
|
1280 1281 1282 1283 1284 1285 1286 |
int k, j; char tbuf[16]; struct net_device *dev = n->dev; int hatype = dev->type; read_lock(&n->lock); /* Convert hardware address to XX:XX:XX:XX ... form. */ |
40e4783ee
|
1287 |
#if IS_ENABLED(CONFIG_AX25) |
1da177e4c
|
1288 1289 1290 1291 1292 |
if (hatype == ARPHRD_AX25 || hatype == ARPHRD_NETROM) ax2asc2((ax25_address *)n->ha, hbuffer); else { #endif for (k = 0, j = 0; k < HBUFFERLEN - 3 && j < dev->addr_len; j++) { |
51f82a2b1
|
1293 1294 |
hbuffer[k++] = hex_asc_hi(n->ha[j]); hbuffer[k++] = hex_asc_lo(n->ha[j]); |
1da177e4c
|
1295 1296 |
hbuffer[k++] = ':'; } |
a3e8ee682
|
1297 1298 1299 |
if (k != 0) --k; hbuffer[k] = 0; |
40e4783ee
|
1300 |
#if IS_ENABLED(CONFIG_AX25) |
1da177e4c
|
1301 1302 |
} #endif |
673d57e72
|
1303 |
sprintf(tbuf, "%pI4", n->primary_key); |
1da177e4c
|
1304 1305 1306 1307 1308 1309 1310 1311 1312 1313 1314 1315 |
seq_printf(seq, "%-16s 0x%-10x0x%-10x%s * %s ", tbuf, hatype, arp_state_to_flags(n), hbuffer, dev->name); read_unlock(&n->lock); } static void arp_format_pneigh_entry(struct seq_file *seq, struct pneigh_entry *n) { struct net_device *dev = n->dev; int hatype = dev ? dev->type : 0; char tbuf[16]; |
673d57e72
|
1316 |
sprintf(tbuf, "%pI4", n->key); |
1da177e4c
|
1317 1318 1319 1320 1321 1322 1323 1324 1325 1326 1327 1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338 1339 1340 1341 1342 1343 1344 1345 1346 1347 1348 1349 |
seq_printf(seq, "%-16s 0x%-10x0x%-10x%s * %s ", tbuf, hatype, ATF_PUBL | ATF_PERM, "00:00:00:00:00:00", dev ? dev->name : "*"); } static int arp_seq_show(struct seq_file *seq, void *v) { if (v == SEQ_START_TOKEN) { seq_puts(seq, "IP address HW type Flags " "HW address Mask Device "); } else { struct neigh_seq_state *state = seq->private; if (state->flags & NEIGH_SEQ_IS_PNEIGH) arp_format_pneigh_entry(seq, v); else arp_format_neigh_entry(seq, v); } return 0; } static void *arp_seq_start(struct seq_file *seq, loff_t *pos) { /* Don't want to confuse "arp -a" w/ magic entries, * so we tell the generic iterator to skip NUD_NOARP. */ return neigh_seq_start(seq, pos, &arp_tbl, NEIGH_SEQ_SKIP_NOARP); } /* ------------------------------------------------------------------------ */ |
f690808e1
|
1350 |
static const struct seq_operations arp_seq_ops = { |
deffd7775
|
1351 1352 1353 1354 |
.start = arp_seq_start, .next = neigh_seq_next, .stop = neigh_seq_stop, .show = arp_seq_show, |
1da177e4c
|
1355 1356 1357 1358 |
}; static int arp_seq_open(struct inode *inode, struct file *file) { |
426b5303e
|
1359 1360 |
return seq_open_net(inode, file, &arp_seq_ops, sizeof(struct neigh_seq_state)); |
1da177e4c
|
1361 |
} |
9a32144e9
|
1362 |
static const struct file_operations arp_seq_fops = { |
1da177e4c
|
1363 1364 1365 1366 |
.owner = THIS_MODULE, .open = arp_seq_open, .read = seq_read, .llseek = seq_lseek, |
426b5303e
|
1367 |
.release = seq_release_net, |
1da177e4c
|
1368 |
}; |
ffc31d3d7
|
1369 1370 |
static int __net_init arp_net_init(struct net *net) |
1da177e4c
|
1371 |
{ |
ffc31d3d7
|
1372 |
if (!proc_net_fops_create(net, "arp", S_IRUGO, &arp_seq_fops)) |
1da177e4c
|
1373 1374 1375 |
return -ENOMEM; return 0; } |
ffc31d3d7
|
1376 1377 1378 1379 1380 1381 1382 1383 1384 1385 1386 1387 1388 1389 |
static void __net_exit arp_net_exit(struct net *net) { proc_net_remove(net, "arp"); } static struct pernet_operations arp_net_ops = { .init = arp_net_init, .exit = arp_net_exit, }; static int __init arp_proc_init(void) { return register_pernet_subsys(&arp_net_ops); } |
1da177e4c
|
1390 1391 1392 1393 1394 1395 1396 1397 |
#else /* CONFIG_PROC_FS */ static int __init arp_proc_init(void) { return 0; } #endif /* CONFIG_PROC_FS */ |