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Diffstat (limited to 'include/net/ipv6.h')
-rw-r--r--include/net/ipv6.h44
1 files changed, 44 insertions, 0 deletions
diff --git a/include/net/ipv6.h b/include/net/ipv6.h
index 213612f1680c..5b38bf1a586b 100644
--- a/include/net/ipv6.h
+++ b/include/net/ipv6.h
@@ -151,6 +151,17 @@ struct frag_hdr {
__be32 identification;
};
+/*
+ * Jumbo payload option, as described in RFC 2675 2.
+ */
+struct hop_jumbo_hdr {
+ u8 nexthdr;
+ u8 hdrlen;
+ u8 tlv_type; /* IPV6_TLV_JUMBO, 0xC2 */
+ u8 tlv_len; /* 4 */
+ __be32 jumbo_payload_len;
+};
+
#define IP6_MF 0x0001
#define IP6_OFFSET 0xFFF8
@@ -456,6 +467,39 @@ bool ipv6_opt_accepted(const struct sock *sk, const struct sk_buff *skb,
struct ipv6_txoptions *ipv6_update_options(struct sock *sk,
struct ipv6_txoptions *opt);
+/* This helper is specialized for BIG TCP needs.
+ * It assumes the hop_jumbo_hdr will immediately follow the IPV6 header.
+ * It assumes headers are already in skb->head.
+ * Returns 0, or IPPROTO_TCP if a BIG TCP packet is there.
+ */
+static inline int ipv6_has_hopopt_jumbo(const struct sk_buff *skb)
+{
+ const struct hop_jumbo_hdr *jhdr;
+ const struct ipv6hdr *nhdr;
+
+ if (likely(skb->len <= GRO_LEGACY_MAX_SIZE))
+ return 0;
+
+ if (skb->protocol != htons(ETH_P_IPV6))
+ return 0;
+
+ if (skb_network_offset(skb) +
+ sizeof(struct ipv6hdr) +
+ sizeof(struct hop_jumbo_hdr) > skb_headlen(skb))
+ return 0;
+
+ nhdr = ipv6_hdr(skb);
+
+ if (nhdr->nexthdr != NEXTHDR_HOP)
+ return 0;
+
+ jhdr = (const struct hop_jumbo_hdr *) (nhdr + 1);
+ if (jhdr->tlv_type != IPV6_TLV_JUMBO || jhdr->hdrlen != 0 ||
+ jhdr->nexthdr != IPPROTO_TCP)
+ return 0;
+ return jhdr->nexthdr;
+}
+
static inline bool ipv6_accept_ra(struct inet6_dev *idev)
{
/* If forwarding is enabled, RA are not accepted unless the special