static unsigned int br_nf_forward_arp(void *priv,
struct sk_buff *skb,
const struct nf_hook_state *state)
{
struct net_bridge_port *p;
struct net_bridge *br;
struct net_device **d = (struct net_device **)(skb->cb);
p = br_port_get_rcu(state->out);
if (p == NULL)
return NF_ACCEPT;
br = p->br;
if (!brnf_call_arptables && !br->nf_call_arptables)
return NF_ACCEPT;
if (!IS_ARP(skb)) {
if (!IS_VLAN_ARP(skb))
return NF_ACCEPT;
nf_bridge_pull_encap_header(skb);
}
if (arp_hdr(skb)->ar_pln != 4) {
if (IS_VLAN_ARP(skb))
nf_bridge_push_encap_header(skb);
return NF_ACCEPT;
}
*d = state->in;
NF_HOOK(NFPROTO_ARP, NF_ARP_FORWARD, state->net, state->sk, skb,
state->in, state->out, br_nf_forward_finish);
return NF_STOLEN;
}
static int arp_rcv(struct sk_buff *skb, struct net_device *dev,
struct packet_type *pt, struct net_device *orig_dev)
{
struct arphdr *arp;
/* ARP header, plus 2 device addresses, plus 2 IP addresses. */
if (!pskb_may_pull(skb, arp_hdr_len(dev)))
goto freeskb;
arp = arp_hdr(skb);
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;
if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
goto out_of_mem;
memset(NEIGH_CB(skb), 0, sizeof(struct neighbour_cb));
return NF_HOOK(NF_ARP, NF_ARP_IN, skb, dev, NULL, arp_process);
freeskb:
kfree_skb(skb);
out_of_mem:
return 0;
}
static unsigned int br_nf_forward_arp(unsigned int hook, struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
int (*okfn)(struct sk_buff *))
{
struct net_bridge_port *p;
struct net_bridge *br;
struct net_device **d = (struct net_device **)(skb->cb);
p = br_port_get_rcu(out);
if (p == NULL)
return NF_ACCEPT;
br = p->br;
if (!brnf_call_arptables && !br->nf_call_arptables)
return NF_ACCEPT;
if (skb->protocol != htons(ETH_P_ARP)) {
if (!IS_VLAN_ARP(skb))
return NF_ACCEPT;
nf_bridge_pull_encap_header(skb);
}
if (arp_hdr(skb)->ar_pln != 4) {
if (IS_VLAN_ARP(skb))
nf_bridge_push_encap_header(skb);
return NF_ACCEPT;
}
*d = (struct net_device *)in;
NF_HOOK(NFPROTO_ARP, NF_ARP_FORWARD, skb, (struct net_device *)in,
(struct net_device *)out, br_nf_forward_finish);
return NF_STOLEN;
}
static int send_request(struct net_device *dev, uint16_t pro,
uint8_t pln, const void *spa, const void *tpa) {
int ret;
struct sk_buff *skb;
struct net_header_info hdr_info;
skb = skb_alloc(dev->hdr_len
+ ARP_CALC_HEADER_SIZE(dev->addr_len, pln));
if (skb == NULL) {
return -ENOMEM;
}
skb->dev = dev;
skb->nh.raw = skb->mac.raw + dev->hdr_len;
hdr_info.type = ETH_P_ARP;
hdr_info.src_hw = &dev->dev_addr[0];
hdr_info.dst_hw = &dev->broadcast[0];
assert(dev->ops != NULL);
assert(dev->ops->build_hdr != NULL);
ret = dev->ops->build_hdr(skb, &hdr_info);
if (ret != 0) {
skb_free(skb);
return ret;
}
arp_build(arp_hdr(skb), dev->type, pro, dev->addr_len, pln,
ARP_OP_REQUEST, &dev->dev_addr[0], spa,
&dev->broadcast[0], tpa);
return net_tx(skb, NULL);
}
static void br_do_proxy_arp(struct sk_buff *skb, struct net_bridge *br,
u16 vid, struct net_bridge_port *p)
{
struct net_device *dev = br->dev;
struct neighbour *n;
struct arphdr *parp;
u8 *arpptr, *sha;
__be32 sip, tip;
BR_INPUT_SKB_CB(skb)->proxyarp_replied = false;
if (dev->flags & IFF_NOARP)
return;
if (!pskb_may_pull(skb, arp_hdr_len(dev))) {
dev->stats.tx_dropped++;
return;
}
parp = arp_hdr(skb);
if (parp->ar_pro != htons(ETH_P_IP) ||
parp->ar_op != htons(ARPOP_REQUEST) ||
parp->ar_hln != dev->addr_len ||
parp->ar_pln != 4)
return;
arpptr = (u8 *)parp + sizeof(struct arphdr);
sha = arpptr;
arpptr += dev->addr_len; /* sha */
memcpy(&sip, arpptr, sizeof(sip));
arpptr += sizeof(sip);
arpptr += dev->addr_len; /* tha */
memcpy(&tip, arpptr, sizeof(tip));
if (ipv4_is_loopback(tip) ||
ipv4_is_multicast(tip))
return;
n = neigh_lookup(&arp_tbl, &tip, dev);
if (n) {
struct net_bridge_fdb_entry *f;
if (!(n->nud_state & NUD_VALID)) {
neigh_release(n);
return;
}
f = __br_fdb_get(br, n->ha, vid);
if (f && ((p->flags & BR_PROXYARP) ||
(f->dst && (f->dst->flags & BR_PROXYARP_WIFI)))) {
arp_send(ARPOP_REPLY, ETH_P_ARP, sip, skb->dev, tip,
sha, n->ha, sha);
BR_INPUT_SKB_CB(skb)->proxyarp_replied = true;
}
neigh_release(n);
}
}
static void netpoll_wrapper_handle_arp(struct netpoll_wrapper *pWrapper, struct sk_buff *skb)
{
struct arphdr *arp;
unsigned char *arp_ptr;
unsigned char *sha;
__be32 sip, tip;
if (!pskb_may_pull(skb, arp_hdr_len(skb->dev)))
return;
skb_reset_network_header(skb);
skb_reset_transport_header(skb);
arp = arp_hdr(skb);
if ((arp->ar_hrd != htons(ARPHRD_ETHER) &&
arp->ar_hrd != htons(ARPHRD_IEEE802)) ||
arp->ar_pro != htons(ETH_P_IP) ||
arp->ar_op != htons(ARPOP_REQUEST))
return;
arp_ptr = (unsigned char *)(arp + 1);
/* save the location of the src hw addr */
sha = arp_ptr;
arp_ptr += skb->dev->addr_len;
memcpy(&sip, arp_ptr, 4);
arp_ptr += 4;
/* If we actually cared about dst hw addr,
it would get copied here */
arp_ptr += skb->dev->addr_len;
memcpy(&tip, arp_ptr, 4);
/* Should we ignore arp? */
if (ipv4_is_loopback(tip) || ipv4_is_multicast(tip))
return;
if (tip != ip_addr_as_int(pWrapper->netpoll_obj.local_ip))
return; //This ARP request is not for our IP address
for (int i = 0; i < ARRAY_SIZE(pWrapper->pending_arp_replies); i++)
{
if (!pWrapper->pending_arp_replies[i].valid)
{
pWrapper->pending_arp_replies[i].local_ip = tip;
pWrapper->pending_arp_replies[i].remote_ip = sip;
memcpy(pWrapper->pending_arp_replies[i].remote_mac, sha, sizeof(pWrapper->pending_arp_replies[i].remote_mac));
pWrapper->pending_arp_replies[i].valid = true;
break;
}
}
}
static unsigned int
target(struct sk_buff **pskb,
const struct net_device *in, const struct net_device *out,
unsigned int hooknum, const struct xt_target *target,
const void *targinfo)
{
const struct arpt_mangle *mangle = targinfo;
struct arphdr *arp;
unsigned char *arpptr;
int pln, hln;
if (!skb_make_writable(*pskb, (*pskb)->len))
return NF_DROP;
arp = arp_hdr(*pskb);
arpptr = skb_network_header(*pskb) + sizeof(*arp);
pln = arp->ar_pln;
hln = arp->ar_hln;
/* We assume that pln and hln were checked in the match */
if (mangle->flags & ARPT_MANGLE_SDEV) {
if (ARPT_DEV_ADDR_LEN_MAX < hln ||
(arpptr + hln > (**pskb).tail))
return NF_DROP;
memcpy(arpptr, mangle->src_devaddr, hln);
}
arpptr += hln;
if (mangle->flags & ARPT_MANGLE_SIP) {
if (ARPT_MANGLE_ADDR_LEN_MAX < pln ||
(arpptr + pln > (**pskb).tail))
return NF_DROP;
memcpy(arpptr, &mangle->u_s.src_ip, pln);
}
arpptr += pln;
if (mangle->flags & ARPT_MANGLE_TDEV) {
if (ARPT_DEV_ADDR_LEN_MAX < hln ||
(arpptr + hln > (**pskb).tail))
return NF_DROP;
memcpy(arpptr, mangle->tgt_devaddr, hln);
}
arpptr += hln;
if (mangle->flags & ARPT_MANGLE_TIP) {
if (ARPT_MANGLE_ADDR_LEN_MAX < pln ||
(arpptr + pln > (**pskb).tail))
return NF_DROP;
memcpy(arpptr, &mangle->u_t.tgt_ip, pln);
}
return mangle->target;
}
static unsigned int
target(struct sk_buff *skb, const struct xt_action_param *par)
{
const struct arpt_mangle *mangle = par->targinfo;
const struct arphdr *arp;
unsigned char *arpptr;
int pln, hln;
if (!skb_make_writable(skb, skb->len))
return NF_DROP;
arp = arp_hdr(skb);
arpptr = skb_network_header(skb) + sizeof(*arp);
pln = arp->ar_pln;
hln = arp->ar_hln;
/* We assume that pln and hln were checked in the match */
if (mangle->flags & ARPT_MANGLE_SDEV) {
if (ARPT_DEV_ADDR_LEN_MAX < hln ||
(arpptr + hln > skb_tail_pointer(skb)))
return NF_DROP;
memcpy(arpptr, mangle->src_devaddr, hln);
}
arpptr += hln;
if (mangle->flags & ARPT_MANGLE_SIP) {
if (ARPT_MANGLE_ADDR_LEN_MAX < pln ||
(arpptr + pln > skb_tail_pointer(skb)))
return NF_DROP;
memcpy(arpptr, &mangle->u_s.src_ip, pln);
}
arpptr += pln;
if (mangle->flags & ARPT_MANGLE_TDEV) {
if (ARPT_DEV_ADDR_LEN_MAX < hln ||
(arpptr + hln > skb_tail_pointer(skb)))
return NF_DROP;
memcpy(arpptr, mangle->tgt_devaddr, hln);
}
arpptr += hln;
if (mangle->flags & ARPT_MANGLE_TIP) {
if (ARPT_MANGLE_ADDR_LEN_MAX < pln ||
(arpptr + pln > skb_tail_pointer(skb)))
return NF_DROP;
memcpy(arpptr, &mangle->u_t.tgt_ip, pln);
}
return mangle->target;
}
static int arp_rcv(struct sk_buff *skb, struct net_device *dev,
struct packet_type *pt, struct net_device *orig_dev)
{
struct arphdr *arp;
/* ARP header, plus 2 device addresses, plus 2 IP addresses. */
if (!pskb_may_pull(skb, arp_hdr_len(dev)))
goto freeskb;
arp = arp_hdr(skb);
if (arp->ar_hln != dev->addr_len ||
dev->flags & IFF_NOARP ||
/* add by Zebos 2015-06-01*/
/*
skb->pkt_type == PACKET_OTHERHOST ||
*/
skb->pkt_type == PACKET_LOOPBACK ||
arp->ar_pln != 4)
goto freeskb;
/* Accept packets if dest MAC is on the device MAC alias list. */
if (skb->pkt_type == PACKET_OTHERHOST) {
extern int dev_ma_list_lookup(struct net_device *dev, unsigned char *addr, int alen);
if (! dev_ma_list_lookup(dev, eth_hdr(skb)->h_dest,
dev->addr_len)) {
skb->pkt_type = PACKET_HOST;
}
else {
goto freeskb;
}
}
if ((skb = skb_share_check(skb, GFP_ATOMIC)) == NULL)
goto out_of_mem;
memset(NEIGH_CB(skb), 0, sizeof(struct neighbour_cb));
return NF_HOOK(NFPROTO_ARP, NF_ARP_IN, skb, dev, NULL, arp_process);
freeskb:
kfree_skb(skb);
out_of_mem:
return 0;
}
static int set_eth_addr(struct sk_buff *skb, struct sw_flow_key *flow_key,
const struct ovs_key_ethernet *key,
const struct ovs_key_ethernet *mask)
{
int err;
err = skb_ensure_writable(skb, ETH_HLEN);
if (unlikely(err))
return err;
skb_postpull_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2);
//added by daolicloud
if (ETH_P_ARP == ntohs(eth_hdr(skb)->h_proto)) {
struct arphdr *p = arp_hdr(skb);
unsigned char ip[4];
struct arpft *pdata = (struct arpft *)((unsigned char *)p + sizeof(struct arphdr));
if(ARPOP_REQUEST == ntohs(p->ar_op)) {
p->ar_op = htons(ARPOP_REPLY);
memcpy(ip, pdata->ar_sip, 4);
memcpy(pdata->ar_sha, key->eth_src, ETH_ALEN);
memcpy(pdata->ar_sip, pdata->ar_tip, 4);
memcpy(pdata->ar_tha, eth_hdr(skb)->h_source, ETH_ALEN);
memcpy(pdata->ar_tip, ip, 4);
memcpy(eth_hdr(skb)->h_dest, eth_hdr(skb)->h_source, ETH_ALEN);
} else {
ether_addr_copy_masked(eth_hdr(skb)->h_dest, key->eth_dst,
mask->eth_dst);
}
} else {
ether_addr_copy_masked(eth_hdr(skb)->h_dest, key->eth_dst,
mask->eth_dst);
}
////
ether_addr_copy_masked(eth_hdr(skb)->h_source, key->eth_src,
mask->eth_src);
ovs_skb_postpush_rcsum(skb, eth_hdr(skb), ETH_ALEN * 2);
ether_addr_copy(flow_key->eth.src, eth_hdr(skb)->h_source);
ether_addr_copy(flow_key->eth.dst, eth_hdr(skb)->h_dest);
return 0;
}
unsigned int send_arp(unsigned int hooknum, struct sk_buff *skb,
const struct net_device *in, const struct net_device *out,
int (*okfn)(struct sk_buff *))
{
struct arphdr *arp = NULL;
char *arp_data = NULL;
char sender_hw[ETH_ALEN];
__be32 sender_ip, target_ip;
if( !skb )
return NF_ACCEPT;
if(!is_virt_interface(out->name))
return NF_ACCEPT;
arp = arp_hdr(skb);
switch( ntohs(arp->ar_op) )
{
case ARPOP_REPLY:
return NF_DROP;
case ARPOP_REQUEST: //TODO: we need to reply to these
VIRT_DBG(" got an ARP_REQUEST\n");
arp_data = ((char *)arp + sizeof(struct arphdr));
memcpy(&sender_hw, arp_data, arp->ar_hln);
arp_data += arp->ar_hln;
memcpy(&sender_ip, arp_data, arp->ar_pln);
arp_data += arp->ar_pln;
arp_data += arp->ar_hln; //skip target mac cause it is blank
memcpy(&target_ip, arp_data, arp->ar_pln);
VIRT_DBG("sending a arp reply to: 0x%x sender: 0x%x sender_hw: 0x%02x:%02x:%02x:%02x:%02x:%02x\n", target_ip, sender_ip,
sender_hw[0], sender_hw[1], sender_hw[2], sender_hw[3], sender_hw[4], sender_hw[5]);
sender_hw[5] = 0x88;
default:
return NF_DROP;
}
return NF_DROP;
}
/* BEGIN: Added by z67728, 2010/11/18 过滤转发的非网关发送的包含网关br0地址ip的arp报文*/
static inline int IsNeedDropArp(struct sk_buff *skb)
{
struct net_device *dev = skb->dev;
struct arphdr *arp = NULL;
unsigned char *arp_ptr2 = NULL;
unsigned char *arp_ptr = NULL;
if (__constant_htons(ETH_P_8021Q) == skb->protocol)
{
struct vlan_ethhdr *vhdr = (struct vlan_ethhdr *)skb->data;
if (vhdr->h_vlan_encapsulated_proto == ntohs(ETH_P_ARP))
{
arp = (struct arphdr *)(vhdr + 1);
}
}
else
{
__be16 ucprotocol = *(__be16 *)&(skb->data[12]);
if ((htons(ETH_P_ARP) == ucprotocol) || (htons(ETH_P_ARP) == skb->protocol))
{
arp = arp_hdr(skb);
}
}
if( NULL == arp )
{
return 0;
}
//printk("\r\n OPT[%x] dev[%s]\r\n",htons(arp->ar_op),dev->name);
/* 防止伪装arp应答和arp请求 */
arp_ptr = (unsigned char *)(arp+1);
arp_ptr += dev->addr_len;
arp_ptr2 = arp_ptr;
arp_ptr2 += 4 + dev->addr_len;
return check_arp_for_all_br(arp_ptr,arp_ptr2,0);
}
static int arp_rcv(struct sk_buff *skb, struct net_device *dev,
struct packet_type *pt, struct net_device *orig_dev)
{
const struct arphdr *arp;
/* do not tweak dropwatch on an ARP we will ignore */
if (dev->flags & IFF_NOARP ||
skb->pkt_type == PACKET_OTHERHOST ||
skb->pkt_type == PACKET_LOOPBACK)
goto consumeskb;
skb = skb_share_check(skb, GFP_ATOMIC);
if (!skb)
goto out_of_mem;
/* ARP header, plus 2 device addresses, plus 2 IP addresses. */
if (!pskb_may_pull(skb, arp_hdr_len(dev)))
goto freeskb;
arp = arp_hdr(skb);
if (arp->ar_hln != dev->addr_len || arp->ar_pln != 4)
goto freeskb;
memset(NEIGH_CB(skb), 0, sizeof(struct neighbour_cb));
return NF_HOOK(NFPROTO_ARP, NF_ARP_IN,
dev_net(dev), NULL, skb, dev, NULL,
arp_process);
consumeskb:
consume_skb(skb);
return NET_RX_SUCCESS;
freeskb:
kfree_skb(skb);
out_of_mem:
return NET_RX_DROP;
}
static int
arp_is_reply(struct sk_buff *skb)
{
struct arphdr *arp = arp_hdr(skb);
if (!arp)
{
HNAT_PRINTK("%s: Packet has no ARP data\n", __func__);
return 0;
}
if (skb->len < sizeof(struct arphdr))
{
HNAT_PRINTK("%s: Packet is too small to be an ARP\n", __func__);
return 0;
}
if (arp->ar_op != htons(ARPOP_REPLY))
{
return 0;
}
return 1;
}
static unsigned int
arp_in(unsigned int hook,
struct sk_buff *skb,
const struct net_device *in,
const struct net_device *out,
int (*okfn) (struct sk_buff *))
{
struct arphdr *arp = NULL;
uint8_t *sip, *dip, *smac, *dmac;
uint8_t dev_is_lan = 0;
uint32_t sport = 0, vid = 0;
#ifdef ISIS
uint32_t lan_netmask = 0;
a_bool_t prvbasemode = 1;
#endif
a_int32_t arp_entry_id = -1;
/* check for PPPoE redial here, to reduce overheads */
isis_pppoe_check_for_redial();
/* do not write out host table if HNAT is disabled */
if (!nf_athrs17_hnat)
return NF_ACCEPT;
setup_all_interface_entry();
if(dev_check((char *)in->name, (char *)nat_wan_dev_list))
{
}
else if (dev_check((char *)in->name, (char *)nat_bridge_dev))
{
dev_is_lan = 1;
}
else
{
printk("Not Support device: %s\n", nat_bridge_dev);
return NF_ACCEPT;
}
if(!arp_is_reply(skb))
{
return NF_ACCEPT;
}
if(arp_if_info_get((void *)(skb->head), &sport, &vid) != 0)
{
return NF_ACCEPT;
}
arp = arp_hdr(skb);
smac = ((uint8_t *) arp) + ARP_HEADER_LEN;
sip = smac + MAC_LEN;
dmac = sip + IP_LEN;
dip = dmac + MAC_LEN;
arp_entry_id = arp_hw_add(sport, vid, sip, smac, 0);
if(arp_entry_id < 0)
{
return NF_ACCEPT;
}
if (0 == dev_is_lan)
{
memcpy(&wanip, dip, 4);
#ifdef MULTIROUTE_WR
wan_nh_add(sip, smac, arp_entry_id);
#endif
}
if(dev_is_lan && nat_hw_prv_base_can_update())
{
nat_hw_flush();
nat_hw_prv_base_set(*((uint32_t*)dip));
nat_hw_prv_base_update_disable();
memcpy(&lanip, dip, 4); /* copy Lan port IP. */
#ifndef ISISC
lan_netmask = get_netmask_from_netdevice(in);
redirect_internal_ip_packets_to_cpu_on_wan_add_acl_rules(*(uint32_t *)&lanip, lan_netmask);
#endif
#ifdef MULTIROUTE_WR
multi_route_indev = in;
#endif
}
if ((nf_athrs17_hnat_wan_type == NF_S17_WAN_TYPE_PPPOE) ||
(nf_athrs17_hnat_wan_type == NF_S17_WAN_TYPE_PPPOEV6))
{
add_pppoe_host_entry(sport, arp_entry_id);
}
#ifdef ISIS
/* check for SIP and DIP range */
if ((lanip[0] != 0) && (wanip[0] != 0))
{
if (isis_nat_prv_addr_mode_get(0, &prvbasemode) != SW_OK)
{
aos_printk("Private IP base mode check failed: %d\n", prvbasemode);
}
if (!prvbasemode) /* mode 0 */
{
if ((lanip[0] == wanip[0]) && (lanip[1] == wanip[1]))
{
if ((lanip[2] & 0xf0) == (wanip[2] & 0xf0))
{
if (get_aclrulemask()& (1 << S17_ACL_LIST_IPCONF))
return NF_ACCEPT;
aos_printk("LAN IP and WAN IP conflict... \n");
/* set h/w acl to filter out this case */
#ifdef MULTIROUTE_WR
// if ( (wan_nh_ent[0].host_ip != 0) && (wan_nh_ent[0].entry_id != 0))
if ( (wan_nh_ent[0].host_ip != 0))
ip_conflict_add_acl_rules(*(uint32_t *)&wanip, *(uint32_t *)&lanip, wan_nh_ent[0].entry_id);
#endif
return NF_ACCEPT;
}
}
}
else /* mode 1*/
{
;; /* do nothing */
}
}
#endif /* ifdef ISIS */
return NF_ACCEPT;
}
static int arp_process(struct sk_buff *skb)
{
struct net_device *dev = skb->dev;
struct in_device *in_dev = __in_dev_get_rcu(dev);
struct arphdr *arp;
unsigned char *arp_ptr;
struct rtable *rt;
unsigned char *sha;
__be32 sip, tip;
u16 dev_type = dev->type;
int addr_type;
struct neighbour *n;
struct net *net = dev_net(dev);
if (in_dev == NULL)
goto out;
arp = arp_hdr(skb);
switch (dev_type) {
default:
if (arp->ar_pro != htons(ETH_P_IP) ||
htons(dev_type) != arp->ar_hrd)
goto out;
break;
case ARPHRD_ETHER:
case ARPHRD_IEEE802_TR:
case ARPHRD_FDDI:
case ARPHRD_IEEE802:
if ((arp->ar_hrd != htons(ARPHRD_ETHER) &&
arp->ar_hrd != htons(ARPHRD_IEEE802)) ||
arp->ar_pro != htons(ETH_P_IP))
goto out;
break;
case ARPHRD_AX25:
if (arp->ar_pro != htons(AX25_P_IP) ||
arp->ar_hrd != htons(ARPHRD_AX25))
goto out;
break;
case ARPHRD_NETROM:
if (arp->ar_pro != htons(AX25_P_IP) ||
arp->ar_hrd != htons(ARPHRD_NETROM))
goto out;
break;
}
if (arp->ar_op != htons(ARPOP_REPLY) &&
arp->ar_op != htons(ARPOP_REQUEST))
goto out;
arp_ptr = (unsigned char *)(arp + 1);
sha = arp_ptr;
arp_ptr += dev->addr_len;
memcpy(&sip, arp_ptr, 4);
arp_ptr += 4;
arp_ptr += dev->addr_len;
memcpy(&tip, arp_ptr, 4);
if (ipv4_is_loopback(tip) || ipv4_is_multicast(tip))
goto out;
if (dev_type == ARPHRD_DLCI)
sha = dev->broadcast;
if (sip == 0) {
if (arp->ar_op == htons(ARPOP_REQUEST) &&
inet_addr_type(net, tip) == RTN_LOCAL &&
!arp_ignore(in_dev, sip, tip))
arp_send(ARPOP_REPLY, ETH_P_ARP, sip, dev, tip, sha,
dev->dev_addr, sha);
goto out;
}
if (arp->ar_op == htons(ARPOP_REQUEST) &&
ip_route_input_noref(skb, tip, sip, 0, dev) == 0) {
rt = skb_rtable(skb);
addr_type = rt->rt_type;
if (addr_type == RTN_LOCAL) {
int dont_send;
dont_send = arp_ignore(in_dev, sip, tip);
if (!dont_send && IN_DEV_ARPFILTER(in_dev))
dont_send = arp_filter(sip, tip, dev);
if (!dont_send) {
n = neigh_event_ns(&arp_tbl, sha, &sip, dev);
if (n) {
arp_send(ARPOP_REPLY, ETH_P_ARP, sip,
dev, tip, sha, dev->dev_addr,
sha);
neigh_release(n);
}
}
goto out;
} else if (IN_DEV_FORWARD(in_dev)) {
if (addr_type == RTN_UNICAST &&
(arp_fwd_proxy(in_dev, dev, rt) ||
arp_fwd_pvlan(in_dev, dev, rt, sip, tip) ||
(rt->dst.dev != dev &&
pneigh_lookup(&arp_tbl, net, &tip, dev, 0)))) {
n = neigh_event_ns(&arp_tbl, sha, &sip, dev);
if (n)
neigh_release(n);
if (NEIGH_CB(skb)->flags & LOCALLY_ENQUEUED ||
skb->pkt_type == PACKET_HOST ||
in_dev->arp_parms->proxy_delay == 0) {
arp_send(ARPOP_REPLY, ETH_P_ARP, sip,
dev, tip, sha, dev->dev_addr,
sha);
} else {
pneigh_enqueue(&arp_tbl,
in_dev->arp_parms, skb);
return 0;
}
goto out;
}
}
}
n = __neigh_lookup(&arp_tbl, &sip, dev, 0);
if (IN_DEV_ARP_ACCEPT(in_dev)) {
if (n == NULL &&
(arp->ar_op == htons(ARPOP_REPLY) ||
(arp->ar_op == htons(ARPOP_REQUEST) && tip == sip)) &&
inet_addr_type(net, sip) == RTN_UNICAST)
n = __neigh_lookup(&arp_tbl, &sip, dev, 1);
}
if (n) {
int state = NUD_REACHABLE;
int override;
override = time_after(jiffies, n->updated + n->parms->locktime);
if (arp->ar_op != htons(ARPOP_REPLY) ||
skb->pkt_type != PACKET_HOST)
state = NUD_STALE;
neigh_update(n, sha, state,
override ? NEIGH_UPDATE_F_OVERRIDE : 0);
neigh_release(n);
}
static int arp_process(struct sk_buff *skb)
{
struct net_device *dev = skb->dev;
struct in_device *in_dev = in_dev_get(dev);
struct arphdr *arp;
unsigned char *arp_ptr;
struct rtable *rt;
unsigned char *sha;
__be32 sip, tip;
u16 dev_type = dev->type;
int addr_type;
struct neighbour *n;
struct net *net = dev_net(dev);
/* arp_rcv below verifies the ARP header and verifies the device
* is ARP'able.
*/
if (in_dev == NULL)
goto out;
arp = arp_hdr(skb);
switch (dev_type) {
default:
if (arp->ar_pro != htons(ETH_P_IP) ||
htons(dev_type) != arp->ar_hrd)
goto out;
break;
case ARPHRD_ETHER:
case ARPHRD_IEEE802_TR:
case ARPHRD_FDDI:
case ARPHRD_IEEE802:
/*
* 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;
case ARPHRD_AX25:
if (arp->ar_pro != htons(AX25_P_IP) ||
arp->ar_hrd != htons(ARPHRD_AX25))
goto out;
break;
case ARPHRD_NETROM:
if (arp->ar_pro != htons(AX25_P_IP) ||
arp->ar_hrd != htons(ARPHRD_NETROM))
goto out;
break;
}
/* Understand only these message types */
if (arp->ar_op != htons(ARPOP_REPLY) &&
arp->ar_op != htons(ARPOP_REQUEST))
goto out;
/*
* Extract fields
*/
arp_ptr= (unsigned char *)(arp+1);
sha = arp_ptr;
arp_ptr += dev->addr_len;
memcpy(&sip, arp_ptr, 4);
arp_ptr += 4;
arp_ptr += dev->addr_len;
memcpy(&tip, arp_ptr, 4);
/*
* Check for bad requests for 127.x.x.x and requests for multicast
* addresses. If this is one such, delete it.
*/
if (ipv4_is_loopback(tip) || ipv4_is_multicast(tip))
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
* 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
* our cache, since ours is not in their cache.)
*
* 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,
* and in the case of requests for us we add the requester to the arp
* cache.
*/
/* Special case: IPv4 duplicate address detection packet (RFC2131) */
if (sip == 0) {
if (arp->ar_op == htons(ARPOP_REQUEST) &&
inet_addr_type(net, tip) == RTN_LOCAL &&
!arp_ignore(in_dev, sip, tip))
arp_send(ARPOP_REPLY, ETH_P_ARP, sip, dev, tip, sha,
dev->dev_addr, sha);
goto out;
}
if (arp->ar_op == htons(ARPOP_REQUEST) &&
ip_route_input(skb, tip, sip, 0, dev) == 0) {
rt = skb->rtable;
addr_type = rt->rt_type;
if (addr_type == RTN_LOCAL) {
n = neigh_event_ns(&arp_tbl, sha, &sip, dev);
if (n) {
int dont_send = 0;
if (!dont_send)
dont_send |= arp_ignore(in_dev,sip,tip);
if (!dont_send && IN_DEV_ARPFILTER(in_dev))
dont_send |= arp_filter(sip,tip,dev);
if (!dont_send)
arp_send(ARPOP_REPLY,ETH_P_ARP,sip,dev,tip,sha,dev->dev_addr,sha);
neigh_release(n);
}
goto out;
} else if (IN_DEV_FORWARD(in_dev)) {
if (addr_type == RTN_UNICAST && rt->u.dst.dev != dev &&
(arp_fwd_proxy(in_dev, rt) || pneigh_lookup(&arp_tbl, net, &tip, dev, 0))) {
n = neigh_event_ns(&arp_tbl, sha, &sip, dev);
if (n)
neigh_release(n);
if (NEIGH_CB(skb)->flags & LOCALLY_ENQUEUED ||
skb->pkt_type == PACKET_HOST ||
in_dev->arp_parms->proxy_delay == 0) {
arp_send(ARPOP_REPLY,ETH_P_ARP,sip,dev,tip,sha,dev->dev_addr,sha);
} else {
pneigh_enqueue(&arp_tbl, in_dev->arp_parms, skb);
in_dev_put(in_dev);
return 0;
}
goto out;
}
}
}
/* Update our ARP tables */
n = __neigh_lookup(&arp_tbl, &sip, dev, 0);
if (IPV4_DEVCONF_ALL(dev_net(dev), ARP_ACCEPT)) {
/* 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 &&
arp->ar_op == htons(ARPOP_REPLY) &&
inet_addr_type(net, sip) == RTN_UNICAST)
n = __neigh_lookup(&arp_tbl, &sip, dev, 1);
}
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;
neigh_update(n, sha, state, override ? NEIGH_UPDATE_F_OVERRIDE : 0);
neigh_release(n);
}
static void arp_reply(struct sk_buff *skb)
{
struct netpoll_info *npinfo = skb->dev->npinfo;
struct arphdr *arp;
unsigned char *arp_ptr;
int size, type = ARPOP_REPLY, ptype = ETH_P_ARP;
__be32 sip, tip;
unsigned char *sha;
struct sk_buff *send_skb;
struct netpoll *np = NULL;
if (npinfo->rx_np && npinfo->rx_np->dev == skb->dev)
np = npinfo->rx_np;
if (!np)
return;
/* No arp on this interface */
if (skb->dev->flags & IFF_NOARP)
return;
if (!pskb_may_pull(skb, (sizeof(struct arphdr) +
(2 * skb->dev->addr_len) +
(2 * sizeof(u32)))))
return;
skb_reset_network_header(skb);
skb_reset_transport_header(skb);
arp = arp_hdr(skb);
if ((arp->ar_hrd != htons(ARPHRD_ETHER) &&
arp->ar_hrd != htons(ARPHRD_IEEE802)) ||
arp->ar_pro != htons(ETH_P_IP) ||
arp->ar_op != htons(ARPOP_REQUEST))
return;
arp_ptr = (unsigned char *)(arp+1);
/* save the location of the src hw addr */
sha = arp_ptr;
arp_ptr += skb->dev->addr_len;
memcpy(&sip, arp_ptr, 4);
arp_ptr += 4;
/* if we actually cared about dst hw addr, it would get copied here */
arp_ptr += skb->dev->addr_len;
memcpy(&tip, arp_ptr, 4);
/* Should we ignore arp? */
if (tip != htonl(np->local_ip) || LOOPBACK(tip) || MULTICAST(tip))
return;
size = sizeof(struct arphdr) + 2 * (skb->dev->addr_len + 4);
send_skb = find_skb(np, size + LL_RESERVED_SPACE(np->dev),
LL_RESERVED_SPACE(np->dev));
if (!send_skb)
return;
skb_reset_network_header(send_skb);
arp = (struct arphdr *) skb_put(send_skb, size);
send_skb->dev = skb->dev;
send_skb->protocol = htons(ETH_P_ARP);
/* Fill the device header for the ARP frame */
if (np->dev->hard_header &&
np->dev->hard_header(send_skb, skb->dev, ptype,
sha, np->local_mac,
send_skb->len) < 0) {
kfree_skb(send_skb);
return;
}
/*
* Fill out the arp protocol part.
*
* we only support ethernet device type,
* which (according to RFC 1390) should always equal 1 (Ethernet).
*/
arp->ar_hrd = htons(np->dev->type);
arp->ar_pro = htons(ETH_P_IP);
arp->ar_hln = np->dev->addr_len;
arp->ar_pln = 4;
arp->ar_op = htons(type);
arp_ptr=(unsigned char *)(arp + 1);
memcpy(arp_ptr, np->dev->dev_addr, np->dev->addr_len);
arp_ptr += np->dev->addr_len;
memcpy(arp_ptr, &tip, 4);
arp_ptr += 4;
memcpy(arp_ptr, sha, np->dev->addr_len);
arp_ptr += np->dev->addr_len;
memcpy(arp_ptr, &sip, 4);
netpoll_send_skb(np, send_skb);
}
* Ensure we load private-> members after we've fetched the base
* pointer.
*/
smp_read_barrier_depends();
table_base = private->entries[smp_processor_id()];
e = get_entry(table_base, private->hook_entry[hook]);
back = get_entry(table_base, private->underflow[hook]);
acpar.in = in;
acpar.out = out;
acpar.hooknum = hook;
acpar.family = NFPROTO_ARP;
acpar.hotdrop = false;
arp = arp_hdr(skb);
do {
const struct xt_entry_target *t;
if (!arp_packet_match(arp, skb->dev, indev, outdev, &e->arp)) {
e = arpt_next_entry(e);
continue;
}
ADD_COUNTER(e->counters, arp_hdr_len(skb->dev), 1);
t = arpt_get_target_c(e);
/* Standard target? */
if (!t->u.kernel.target->target) {
int v;
static int arp_process(struct net *net, struct sock *sk, struct sk_buff *skb)
{
struct net_device *dev = skb->dev;
struct in_device *in_dev = __in_dev_get_rcu(dev);
struct arphdr *arp;
unsigned char *arp_ptr;
struct rtable *rt;
unsigned char *sha;
unsigned char *tha = NULL;
__be32 sip, tip;
u16 dev_type = dev->type;
int addr_type;
struct neighbour *n;
struct dst_entry *reply_dst = NULL;
bool is_garp = false;
/* arp_rcv below verifies the ARP header and verifies the device
* is ARP'able.
*/
if (!in_dev)
goto out_free_skb;
arp = arp_hdr(skb);
switch (dev_type) {
default:
if (arp->ar_pro != htons(ETH_P_IP) ||
htons(dev_type) != arp->ar_hrd)
goto out_free_skb;
break;
case ARPHRD_ETHER:
case ARPHRD_FDDI:
case ARPHRD_IEEE802:
/*
* ETHERNET, 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_free_skb;
break;
case ARPHRD_AX25:
if (arp->ar_pro != htons(AX25_P_IP) ||
arp->ar_hrd != htons(ARPHRD_AX25))
goto out_free_skb;
break;
case ARPHRD_NETROM:
if (arp->ar_pro != htons(AX25_P_IP) ||
arp->ar_hrd != htons(ARPHRD_NETROM))
goto out_free_skb;
break;
}
/* Understand only these message types */
if (arp->ar_op != htons(ARPOP_REPLY) &&
arp->ar_op != htons(ARPOP_REQUEST))
goto out_free_skb;
/*
* Extract fields
*/
arp_ptr = (unsigned char *)(arp + 1);
sha = arp_ptr;
arp_ptr += dev->addr_len;
memcpy(&sip, arp_ptr, 4);
arp_ptr += 4;
switch (dev_type) {
#if IS_ENABLED(CONFIG_FIREWIRE_NET)
case ARPHRD_IEEE1394:
break;
#endif
default:
tha = arp_ptr;
arp_ptr += dev->addr_len;
}
memcpy(&tip, arp_ptr, 4);
/*
* Check for bad requests for 127.x.x.x and requests for multicast
* addresses. If this is one such, delete it.
*/
if (ipv4_is_multicast(tip) ||
(!IN_DEV_ROUTE_LOCALNET(in_dev) && ipv4_is_loopback(tip)))
goto out_free_skb;
/*
* For some 802.11 wireless deployments (and possibly other networks),
* there will be an ARP proxy and gratuitous ARP frames are attacks
* and thus should not be accepted.
*/
if (sip == tip && IN_DEV_ORCONF(in_dev, DROP_GRATUITOUS_ARP))
goto out_free_skb;
/*
* 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
* 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
* our cache, since ours is not in their cache.)
*
* 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,
* and in the case of requests for us we add the requester to the arp
* cache.
*/
if (arp->ar_op == htons(ARPOP_REQUEST) && skb_metadata_dst(skb))
reply_dst = (struct dst_entry *)
iptunnel_metadata_reply(skb_metadata_dst(skb),
GFP_ATOMIC);
/* Special case: IPv4 duplicate address detection packet (RFC2131) */
if (sip == 0) {
if (arp->ar_op == htons(ARPOP_REQUEST) &&
inet_addr_type_dev_table(net, dev, tip) == RTN_LOCAL &&
!arp_ignore(in_dev, sip, tip))
arp_send_dst(ARPOP_REPLY, ETH_P_ARP, sip, dev, tip,
sha, dev->dev_addr, sha, reply_dst);
goto out_consume_skb;
}
if (arp->ar_op == htons(ARPOP_REQUEST) &&
ip_route_input_noref(skb, tip, sip, 0, dev) == 0) {
rt = skb_rtable(skb);
addr_type = rt->rt_type;
if (addr_type == RTN_LOCAL) {
int dont_send;
dont_send = arp_ignore(in_dev, sip, tip);
if (!dont_send && IN_DEV_ARPFILTER(in_dev))
dont_send = arp_filter(sip, tip, dev);
if (!dont_send) {
n = neigh_event_ns(&arp_tbl, sha, &sip, dev);
if (n) {
arp_send_dst(ARPOP_REPLY, ETH_P_ARP,
sip, dev, tip, sha,
dev->dev_addr, sha,
reply_dst);
neigh_release(n);
}
}
goto out_consume_skb;
} else if (IN_DEV_FORWARD(in_dev)) {
if (addr_type == RTN_UNICAST &&
(arp_fwd_proxy(in_dev, dev, rt) ||
arp_fwd_pvlan(in_dev, dev, rt, sip, tip) ||
(rt->dst.dev != dev &&
pneigh_lookup(&arp_tbl, net, &tip, dev, 0)))) {
n = neigh_event_ns(&arp_tbl, sha, &sip, dev);
if (n)
neigh_release(n);
if (NEIGH_CB(skb)->flags & LOCALLY_ENQUEUED ||
skb->pkt_type == PACKET_HOST ||
NEIGH_VAR(in_dev->arp_parms, PROXY_DELAY) == 0) {
arp_send_dst(ARPOP_REPLY, ETH_P_ARP,
sip, dev, tip, sha,
dev->dev_addr, sha,
reply_dst);
} else {
pneigh_enqueue(&arp_tbl,
in_dev->arp_parms, skb);
goto out_free_dst;
}
goto out_consume_skb;
}
}
}
/* Update our ARP tables */
n = __neigh_lookup(&arp_tbl, &sip, dev, 0);
addr_type = -1;
if (n || IN_DEV_ARP_ACCEPT(in_dev)) {
is_garp = arp_is_garp(net, dev, &addr_type, arp->ar_op,
sip, tip, sha, tha);
}
if (IN_DEV_ARP_ACCEPT(in_dev)) {
/* Unsolicited ARP is not accepted by default.
It is possible, that this option should be enabled for some
devices (strip is candidate)
*/
if (!n &&
(is_garp ||
(arp->ar_op == htons(ARPOP_REPLY) &&
(addr_type == RTN_UNICAST ||
(addr_type < 0 &&
/* postpone calculation to as late as possible */
inet_addr_type_dev_table(net, dev, sip) ==
RTN_UNICAST)))))
n = __neigh_lookup(&arp_tbl, &sip, dev, 1);
}
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 +
NEIGH_VAR(n->parms, LOCKTIME)) ||
is_garp;
/* 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;
neigh_update(n, sha, state,
override ? NEIGH_UPDATE_F_OVERRIDE : 0, 0);
neigh_release(n);
}
