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 --- include/linux/netfilter_ipv6.h | 2 ++ net/bridge/br_netfilter_ipv6.c | 55 +----------------------------------------- net/netfilter/utils.c | 52 +++++++++++++++++++++++++++++++++++++++ 3 files changed, 55 insertions(+), 54 deletions(-) diff --git a/include/linux/netfilter_ipv6.h b/include/linux/netfilter_ipv6.h index 48314ade1506..7834c0be2831 100644 --- a/include/linux/netfilter_ipv6.h +++ b/include/linux/netfilter_ipv6.h @@ -197,6 +197,8 @@ static inline int nf_cookie_v6_check(const struct ipv6hdr *iph, __sum16 nf_ip6_checksum(struct sk_buff *skb, unsigned int hook, unsigned int dataoff, u_int8_t protocol); +int nf_ip6_check_hbh_len(struct sk_buff *skb, u32 *plen); + int ipv6_netfilter_init(void); void ipv6_netfilter_fini(void); diff --git a/net/bridge/br_netfilter_ipv6.c b/net/bridge/br_netfilter_ipv6.c index a0d6dfb3e255..550039dfc31a 100644 --- a/net/bridge/br_netfilter_ipv6.c +++ b/net/bridge/br_netfilter_ipv6.c @@ -40,59 +40,6 @@ #include #endif -/* We only check the length. A bridge shouldn't do any hop-by-hop stuff - * anyway - */ -static int br_nf_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 -1; - nh = (unsigned char *)(ipv6_hdr(skb) + 1); - len = (nh[1] + 1) << 3; - - if (!pskb_may_pull(skb, off + len)) - return -1; - 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 -1; - optlen = nh[off + 1] + 2; - if (optlen > len) - return -1; - - if (nh[off] == IPV6_TLV_JUMBO) { - u32 pkt_len; - - if (nh[off + 1] != 4 || (off & 3) != 2) - return -1; - pkt_len = ntohl(*(__be32 *)(nh + off + 2)); - if (pkt_len <= IPV6_MAXPLEN || - ipv6_hdr(skb)->payload_len) - return -1; - if (pkt_len > skb->len - sizeof(struct ipv6hdr)) - return -1; - *plen = pkt_len; - } - off += optlen; - len -= optlen; - } - - return len ? -1 : 0; -} - int br_validate_ipv6(struct net *net, struct sk_buff *skb) { const struct ipv6hdr *hdr; @@ -112,7 +59,7 @@ int br_validate_ipv6(struct net *net, struct sk_buff *skb) goto inhdr_error; pkt_len = ntohs(hdr->payload_len); - if (hdr->nexthdr == NEXTHDR_HOP && br_nf_check_hbh_len(skb, &pkt_len)) + if (hdr->nexthdr == NEXTHDR_HOP && nf_ip6_check_hbh_len(skb, &pkt_len)) goto drop; if (pkt_len + ip6h_len > skb->len) { 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