diff options
Diffstat (limited to 'net/wireless/util.c')
-rw-r--r-- | net/wireless/util.c | 51 |
1 files changed, 51 insertions, 0 deletions
diff --git a/net/wireless/util.c b/net/wireless/util.c index ca3361a3e750..a52a0eb44aa0 100644 --- a/net/wireless/util.c +++ b/net/wireless/util.c @@ -1872,3 +1872,54 @@ EXPORT_SYMBOL(rfc1042_header); const unsigned char bridge_tunnel_header[] __aligned(2) = { 0xaa, 0xaa, 0x03, 0x00, 0x00, 0xf8 }; EXPORT_SYMBOL(bridge_tunnel_header); + +bool cfg80211_is_gratuitous_arp_unsolicited_na(struct sk_buff *skb) +{ + const struct ethhdr *eth = (void *)skb->data; + const struct { + struct arphdr hdr; + u8 ar_sha[ETH_ALEN]; + u8 ar_sip[4]; + u8 ar_tha[ETH_ALEN]; + u8 ar_tip[4]; + } __packed *arp; + const struct ipv6hdr *ipv6; + const struct icmp6hdr *icmpv6; + + switch (eth->h_proto) { + case cpu_to_be16(ETH_P_ARP): + /* can't say - but will probably be dropped later anyway */ + if (!pskb_may_pull(skb, sizeof(*eth) + sizeof(*arp))) + return false; + + arp = (void *)(eth + 1); + + if ((arp->hdr.ar_op == cpu_to_be16(ARPOP_REPLY) || + arp->hdr.ar_op == cpu_to_be16(ARPOP_REQUEST)) && + !memcmp(arp->ar_sip, arp->ar_tip, sizeof(arp->ar_sip))) + return true; + break; + case cpu_to_be16(ETH_P_IPV6): + /* can't say - but will probably be dropped later anyway */ + if (!pskb_may_pull(skb, sizeof(*eth) + sizeof(*ipv6) + + sizeof(*icmpv6))) + return false; + + ipv6 = (void *)(eth + 1); + icmpv6 = (void *)(ipv6 + 1); + + if (icmpv6->icmp6_type == NDISC_NEIGHBOUR_ADVERTISEMENT && + !memcmp(&ipv6->saddr, &ipv6->daddr, sizeof(ipv6->saddr))) + return true; + break; + default: + /* + * no need to support other protocols, proxy service isn't + * specified for any others + */ + break; + } + + return false; +} +EXPORT_SYMBOL(cfg80211_is_gratuitous_arp_unsolicited_na); |