Re: [PATCH 5/8] net_sched: cls_flow: use proto_ports_offset() to support AH message

[jamal <hadi@cyberus.ca>]

On Wed, 2010-08-18 at 13:05 +0800, Changli Gao wrote:

> -static int has_ports(u8 protocol)
> -{
> -	switch (protocol) {
> -	case IPPROTO_TCP:
> -	case IPPROTO_UDP:
> -	case IPPROTO_UDPLITE:
> -	case IPPROTO_SCTP:
> -	case IPPROTO_DCCP:
> -	case IPPROTO_ESP:
> -		return 1;
> -	default:
> -		return 0;
> -	}
> -}
> -
>  static u32 flow_get_proto_src(struct sk_buff *skb)
>  {
>  	switch (skb->protocol) {
>  	case htons(ETH_P_IP): {
>  		struct iphdr *iph;
> +		int poff;
>  
>  		if (!pskb_network_may_pull(skb, sizeof(*iph)))
>  			break;
>  		iph = ip_hdr(skb);
> -		if (!(iph->frag_off&htons(IP_MF|IP_OFFSET)) &&
> -		    has_ports(iph->protocol) &&
> -		    pskb_network_may_pull(skb, iph->ihl * 4 + 2))
> -			return ntohs(*(__be16 *)((void *)iph + iph->ihl * 4));
> +		if (iph->frag_off & htons(IP_MF|IP_OFFSET))
> +			break;
> +		poff = proto_ports_offset(iph->protocol);
> +		if (poff >= 0 &&


I dont think this maintains the same semantic. Ex: In the original code
AH returns 0. In your case it returns 4 and passes the above test.
Same with the other spot.

cheers,
jamal