icmp: add helpers to recognize ICMP error packets (15122464) · Commits · 戴 / test

Add two helper functions, one for IPv4 and one for IPv6, to recognize the ICMP packets which are error responses. This packets are special because they have as payload the original header of the packet which generated it (RFC 792 says at least 8 bytes, but Linux actually includes much more than that). Signed-off-by:

Matteo Croce <mcroce@redhat.com> Signed-off-by:

David S. Miller <davem@davemloft.net>

include/linux/icmp.h

+15 −0

Original line number	Diff line number	Diff line
		@@ -20,4 +20,19 @@ static inline struct icmphdr icmp_hdr(const struct sk_buff skb)
		{
		return (struct icmphdr *)skb_transport_header(skb);
		}

		static inline bool icmp_is_err(int type)
		{
		switch (type) {
		case ICMP_DEST_UNREACH:
		case ICMP_SOURCE_QUENCH:
		case ICMP_REDIRECT:
		case ICMP_TIME_EXCEEDED:
		case ICMP_PARAMETERPROB:
		return true;
		}

		return false;
		}

		#endif /* _LINUX_ICMP_H */

include/linux/icmpv6.h

+14 −0

Original line number	Diff line number	Diff line
		@@ -46,4 +46,18 @@ extern void icmpv6_flow_init(struct sock *sk,
		const struct in6_addr *saddr,
		const struct in6_addr *daddr,
		int oif);

		static inline bool icmpv6_is_err(int type)
		{
		switch (type) {
		case ICMPV6_DEST_UNREACH:
		case ICMPV6_PKT_TOOBIG:
		case ICMPV6_TIME_EXCEED:
		case ICMPV6_PARAMPROB:
		return true;
		}

		return false;
		}

		#endif

Admin message