From 28e144cf5f72ce1c304571bc448e37c27495903a Mon Sep 17 00:00:00 2001 From: Xin Long Date: Tue, 7 Mar 2023 16:31:30 -0500 Subject: netfilter: move br_nf_check_hbh_len to utils Rename br_nf_check_hbh_len() to nf_ip6_check_hbh_len() and move it to netfilter utils, so that it can be used by other modules, like ovs and tc. Signed-off-by: Xin Long Reviewed-by: Simon Horman Reviewed-by: Nikolay Aleksandrov Reviewed-by: Aaron Conole Signed-off-by: Florian Westphal --- net/netfilter/utils.c | 52 +++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 52 insertions(+) (limited to 'net/netfilter/utils.c') diff --git a/net/netfilter/utils.c b/net/netfilter/utils.c index 2182d361e273..acef4155f0da 100644 --- a/net/netfilter/utils.c +++ b/net/netfilter/utils.c @@ -215,3 +215,55 @@ int nf_reroute(struct sk_buff *skb, struct nf_queue_entry *entry) } return ret; } + +/* Only get and check the lengths, not do any hop-by-hop stuff. */ +int nf_ip6_check_hbh_len(struct sk_buff *skb, u32 *plen) +{ + int len, off = sizeof(struct ipv6hdr); + unsigned char *nh; + + if (!pskb_may_pull(skb, off + 8)) + return -ENOMEM; + nh = (unsigned char *)(ipv6_hdr(skb) + 1); + len = (nh[1] + 1) << 3; + + if (!pskb_may_pull(skb, off + len)) + return -ENOMEM; + nh = skb_network_header(skb); + + off += 2; + len -= 2; + while (len > 0) { + int optlen; + + if (nh[off] == IPV6_TLV_PAD1) { + off++; + len--; + continue; + } + if (len < 2) + return -EBADMSG; + optlen = nh[off + 1] + 2; + if (optlen > len) + return -EBADMSG; + + if (nh[off] == IPV6_TLV_JUMBO) { + u32 pkt_len; + + if (nh[off + 1] != 4 || (off & 3) != 2) + return -EBADMSG; + pkt_len = ntohl(*(__be32 *)(nh + off + 2)); + if (pkt_len <= IPV6_MAXPLEN || + ipv6_hdr(skb)->payload_len) + return -EBADMSG; + if (pkt_len > skb->len - sizeof(struct ipv6hdr)) + return -EBADMSG; + *plen = pkt_len; + } + off += optlen; + len -= optlen; + } + + return len ? -EBADMSG : 0; +} +EXPORT_SYMBOL_GPL(nf_ip6_check_hbh_len); -- cgit v1.2.3