netfilter: bridge: re-order check_hbh_len()
Prepare check_hbh_len() to be called from newly introduced br_validate_ipv6() in next commit. Signed-off-by: Bernhard Thaler <bernhard.thaler@wvnet.at> Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
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@ -264,6 +264,62 @@ drop:
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return -1;
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}
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/* We only check the length. A bridge shouldn't do any hop-by-hop stuff
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* anyway
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*/
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static int check_hbh_len(struct sk_buff *skb)
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{
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unsigned char *raw = (u8 *)(ipv6_hdr(skb) + 1);
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u32 pkt_len;
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const unsigned char *nh = skb_network_header(skb);
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int off = raw - nh;
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int len = (raw[1] + 1) << 3;
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if ((raw + len) - skb->data > skb_headlen(skb))
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goto bad;
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off += 2;
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len -= 2;
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while (len > 0) {
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int optlen = nh[off + 1] + 2;
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switch (nh[off]) {
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case IPV6_TLV_PAD1:
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optlen = 1;
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break;
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case IPV6_TLV_PADN:
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break;
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case IPV6_TLV_JUMBO:
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if (nh[off + 1] != 4 || (off & 3) != 2)
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goto bad;
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pkt_len = ntohl(*(__be32 *)(nh + off + 2));
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if (pkt_len <= IPV6_MAXPLEN ||
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ipv6_hdr(skb)->payload_len)
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goto bad;
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if (pkt_len > skb->len - sizeof(struct ipv6hdr))
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goto bad;
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if (pskb_trim_rcsum(skb,
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pkt_len + sizeof(struct ipv6hdr)))
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goto bad;
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nh = skb_network_header(skb);
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break;
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default:
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if (optlen > len)
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goto bad;
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break;
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}
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off += optlen;
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len -= optlen;
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}
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if (len == 0)
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return 0;
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bad:
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return -1;
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}
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static void nf_bridge_update_protocol(struct sk_buff *skb)
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{
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switch (skb->nf_bridge->orig_proto) {
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@ -549,61 +605,6 @@ static struct net_device *setup_pre_routing(struct sk_buff *skb)
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return skb->dev;
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}
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/* We only check the length. A bridge shouldn't do any hop-by-hop stuff anyway */
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static int check_hbh_len(struct sk_buff *skb)
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{
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unsigned char *raw = (u8 *)(ipv6_hdr(skb) + 1);
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u32 pkt_len;
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const unsigned char *nh = skb_network_header(skb);
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int off = raw - nh;
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int len = (raw[1] + 1) << 3;
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if ((raw + len) - skb->data > skb_headlen(skb))
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goto bad;
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off += 2;
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len -= 2;
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while (len > 0) {
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int optlen = nh[off + 1] + 2;
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switch (nh[off]) {
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case IPV6_TLV_PAD1:
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optlen = 1;
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break;
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case IPV6_TLV_PADN:
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break;
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case IPV6_TLV_JUMBO:
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if (nh[off + 1] != 4 || (off & 3) != 2)
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goto bad;
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pkt_len = ntohl(*(__be32 *) (nh + off + 2));
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if (pkt_len <= IPV6_MAXPLEN ||
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ipv6_hdr(skb)->payload_len)
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goto bad;
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if (pkt_len > skb->len - sizeof(struct ipv6hdr))
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goto bad;
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if (pskb_trim_rcsum(skb,
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pkt_len + sizeof(struct ipv6hdr)))
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goto bad;
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nh = skb_network_header(skb);
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break;
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default:
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if (optlen > len)
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goto bad;
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break;
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}
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off += optlen;
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len -= optlen;
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}
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if (len == 0)
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return 0;
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bad:
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return -1;
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}
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/* Replicate the checks that IPv6 does on packet reception and pass the packet
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* to ip6tables, which doesn't support NAT, so things are fairly simple. */
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static unsigned int br_nf_pre_routing_ipv6(const struct nf_hook_ops *ops,
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