Tue, Feb 21, 2017 at 07:50:53PM CET, t...@herbertland.com wrote:
>On Tue, Feb 21, 2017 at 6:33 AM, Jiri Pirko <j...@resnulli.us> wrote:
>> From: Jiri Pirko <j...@mellanox.com>
>>
>> Make the main flow_dissect function a bit smaller and move the ARP
>> dissection into a separate function. Along with that, do the ARP header
>> processing only in case the flow dissection user requires it.
>>
>
>Acked-by: Tom Herbert <t...@herbertland.com>
>
>GRE might also be a good candidate to get its own function.
>
Submitted with GRE bits. Note that I left you ack and Simon's revby out
since I did some cosmetic changes until rfc.
I would be glad if you both can check it again.
Thanks!
>
>> Signed-off-by: Jiri Pirko <j...@mellanox.com>
>> ---
>> net/core/flow_dissector.c | 111
>> ++++++++++++++++++++++++----------------------
>> 1 file changed, 59 insertions(+), 52 deletions(-)
>>
>> diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c
>> index c35aae1..10dc5bb 100644
>> --- a/net/core/flow_dissector.c
>> +++ b/net/core/flow_dissector.c
>> @@ -113,6 +113,61 @@ __be32 __skb_flow_get_ports(const struct sk_buff *skb,
>> int thoff, u8 ip_proto,
>> }
>> EXPORT_SYMBOL(__skb_flow_get_ports);
>>
>> +static bool __skb_flow_dissect_arp(const struct sk_buff *skb,
>> + struct flow_dissector *flow_dissector,
>> + void *target_container, void *data,
>> + int nhoff, int hlen)
>> +{
>> + struct flow_dissector_key_arp *key_arp;
>> + struct {
>> + unsigned char ar_sha[ETH_ALEN];
>> + unsigned char ar_sip[4];
>> + unsigned char ar_tha[ETH_ALEN];
>> + unsigned char ar_tip[4];
>> + } *arp_eth, _arp_eth;
>> + const struct arphdr *arp;
>> + struct arphdr *_arp;
>> +
>> + if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ARP))
>> + return true;
>> +
>> + arp = __skb_header_pointer(skb, nhoff, sizeof(_arp), data,
>> + hlen, &_arp);
>> + if (!arp)
>> + return false;
>> +
>> + if (arp->ar_hrd != htons(ARPHRD_ETHER) ||
>> + arp->ar_pro != htons(ETH_P_IP) ||
>> + arp->ar_hln != ETH_ALEN ||
>> + arp->ar_pln != 4 ||
>> + (arp->ar_op != htons(ARPOP_REPLY) &&
>> + arp->ar_op != htons(ARPOP_REQUEST)))
>> + return false;
>> +
>> + arp_eth = __skb_header_pointer(skb, nhoff + sizeof(_arp),
>> + sizeof(_arp_eth), data,
>> + hlen, &_arp_eth);
>> + if (!arp_eth)
>> + return false;
>> +
>> + key_arp = skb_flow_dissector_target(flow_dissector,
>> + FLOW_DISSECTOR_KEY_ARP,
>> + target_container);
>> +
>> + memcpy(&key_arp->sip, arp_eth->ar_sip, sizeof(key_arp->sip));
>> + memcpy(&key_arp->tip, arp_eth->ar_tip, sizeof(key_arp->tip));
>> +
>> + /* Only store the lower byte of the opcode;
>> + * this covers ARPOP_REPLY and ARPOP_REQUEST.
>> + */
>> + key_arp->op = ntohs(arp->ar_op) & 0xff;
>> +
>> + ether_addr_copy(key_arp->sha, arp_eth->ar_sha);
>> + ether_addr_copy(key_arp->tha, arp_eth->ar_tha);
>> +
>> + return true;
>> +}
>> +
>> /**
>> * __skb_flow_dissect - extract the flow_keys struct and return it
>> * @skb: sk_buff to extract the flow from, can be NULL if the rest are
>> specified
>> @@ -138,7 +193,6 @@ bool __skb_flow_dissect(const struct sk_buff *skb,
>> struct flow_dissector_key_control *key_control;
>> struct flow_dissector_key_basic *key_basic;
>> struct flow_dissector_key_addrs *key_addrs;
>> - struct flow_dissector_key_arp *key_arp;
>> struct flow_dissector_key_ports *key_ports;
>> struct flow_dissector_key_icmp *key_icmp;
>> struct flow_dissector_key_tags *key_tags;
>> @@ -382,59 +436,12 @@ bool __skb_flow_dissect(const struct sk_buff *skb,
>> goto out_good;
>>
>> case htons(ETH_P_ARP):
>> - case htons(ETH_P_RARP): {
>> - struct {
>> - unsigned char ar_sha[ETH_ALEN];
>> - unsigned char ar_sip[4];
>> - unsigned char ar_tha[ETH_ALEN];
>> - unsigned char ar_tip[4];
>> - } *arp_eth, _arp_eth;
>> - const struct arphdr *arp;
>> - struct arphdr *_arp;
>> -
>> - arp = __skb_header_pointer(skb, nhoff, sizeof(_arp), data,
>> - hlen, &_arp);
>> - if (!arp)
>> - goto out_bad;
>> -
>> - if (arp->ar_hrd != htons(ARPHRD_ETHER) ||
>> - arp->ar_pro != htons(ETH_P_IP) ||
>> - arp->ar_hln != ETH_ALEN ||
>> - arp->ar_pln != 4 ||
>> - (arp->ar_op != htons(ARPOP_REPLY) &&
>> - arp->ar_op != htons(ARPOP_REQUEST)))
>> + case htons(ETH_P_RARP):
>> + if (!__skb_flow_dissect_arp(skb, flow_dissector,
>> + target_container, data,
>> + nhoff, hlen))
>> goto out_bad;
>> -
>> - arp_eth = __skb_header_pointer(skb, nhoff + sizeof(_arp),
>> - sizeof(_arp_eth), data,
>> - hlen,
>> - &_arp_eth);
>> - if (!arp_eth)
>> - goto out_bad;
>> -
>> - if (dissector_uses_key(flow_dissector,
>> - FLOW_DISSECTOR_KEY_ARP)) {
>> -
>> - key_arp = skb_flow_dissector_target(flow_dissector,
>> -
>> FLOW_DISSECTOR_KEY_ARP,
>> -
>> target_container);
>> -
>> - memcpy(&key_arp->sip, arp_eth->ar_sip,
>> - sizeof(key_arp->sip));
>> - memcpy(&key_arp->tip, arp_eth->ar_tip,
>> - sizeof(key_arp->tip));
>> -
>> - /* Only store the lower byte of the opcode;
>> - * this covers ARPOP_REPLY and ARPOP_REQUEST.
>> - */
>> - key_arp->op = ntohs(arp->ar_op) & 0xff;
>> -
>> - ether_addr_copy(key_arp->sha, arp_eth->ar_sha);
>> - ether_addr_copy(key_arp->tha, arp_eth->ar_tha);
>> - }
>> -
>> goto out_good;
>> - }
>>
>> default:
>> goto out_bad;
>> --
>> 2.7.4
>>
