Re: [PATCH v2] ipvs: optimize tunnel dumps for icmp errors
From: Julian Anastasov
Date: Wed Mar 18 2020 - 07:37:23 EST
Hello,
On Sun, 15 Mar 2020, Haishuang Yan wrote:
> After strip GRE/UDP tunnel header for icmp errors, it's better to show
> "GRE/UDP" instead of "IPIP" in debug message.
>
> Signed-off-by: Haishuang Yan <yanhaishuang@xxxxxxxxxxxxxxxxxxxx>
Looks good to me, thanks!
Acked-by: Julian Anastasov <ja@xxxxxx>
Simon, this is for -next kernels...
> ---
> v2: Fix wrong proto message
> ---
> net/netfilter/ipvs/ip_vs_core.c | 46 +++++++++++++++++++++++------------------
> 1 file changed, 26 insertions(+), 20 deletions(-)
>
> diff --git a/net/netfilter/ipvs/ip_vs_core.c b/net/netfilter/ipvs/ip_vs_core.c
> index 512259f..d2ac530 100644
> --- a/net/netfilter/ipvs/ip_vs_core.c
> +++ b/net/netfilter/ipvs/ip_vs_core.c
> @@ -1661,8 +1661,9 @@ static int ipvs_gre_decap(struct netns_ipvs *ipvs, struct sk_buff *skb,
> struct ip_vs_protocol *pp;
> struct ip_vs_proto_data *pd;
> unsigned int offset, offset2, ihl, verdict;
> - bool ipip, new_cp = false;
> + bool tunnel, new_cp = false;
> union nf_inet_addr *raddr;
> + char *outer_proto;
>
> *related = 1;
>
> @@ -1703,8 +1704,8 @@ static int ipvs_gre_decap(struct netns_ipvs *ipvs, struct sk_buff *skb,
> return NF_ACCEPT; /* The packet looks wrong, ignore */
> raddr = (union nf_inet_addr *)&cih->daddr;
>
> - /* Special case for errors for IPIP packets */
> - ipip = false;
> + /* Special case for errors for IPIP/UDP/GRE tunnel packets */
> + tunnel = false;
> if (cih->protocol == IPPROTO_IPIP) {
> struct ip_vs_dest *dest;
>
> @@ -1721,7 +1722,8 @@ static int ipvs_gre_decap(struct netns_ipvs *ipvs, struct sk_buff *skb,
> cih = skb_header_pointer(skb, offset, sizeof(_ciph), &_ciph);
> if (cih == NULL)
> return NF_ACCEPT; /* The packet looks wrong, ignore */
> - ipip = true;
> + tunnel = true;
> + outer_proto = "IPIP";
> } else if ((cih->protocol == IPPROTO_UDP || /* Can be UDP encap */
> cih->protocol == IPPROTO_GRE) && /* Can be GRE encap */
> /* Error for our tunnel must arrive at LOCAL_IN */
> @@ -1729,16 +1731,19 @@ static int ipvs_gre_decap(struct netns_ipvs *ipvs, struct sk_buff *skb,
> __u8 iproto;
> int ulen;
>
> - /* Non-first fragment has no UDP header */
> + /* Non-first fragment has no UDP/GRE header */
> if (unlikely(cih->frag_off & htons(IP_OFFSET)))
> return NF_ACCEPT;
> offset2 = offset + cih->ihl * 4;
> - if (cih->protocol == IPPROTO_UDP)
> + if (cih->protocol == IPPROTO_UDP) {
> ulen = ipvs_udp_decap(ipvs, skb, offset2, AF_INET,
> raddr, &iproto);
> - else
> + outer_proto = "UDP";
> + } else {
> ulen = ipvs_gre_decap(ipvs, skb, offset2, AF_INET,
> raddr, &iproto);
> + outer_proto = "GRE";
> + }
> if (ulen > 0) {
> /* Skip IP and UDP/GRE tunnel headers */
> offset = offset2 + ulen;
> @@ -1747,7 +1752,7 @@ static int ipvs_gre_decap(struct netns_ipvs *ipvs, struct sk_buff *skb,
> &_ciph);
> if (cih && cih->version == 4 && cih->ihl >= 5 &&
> iproto == IPPROTO_IPIP)
> - ipip = true;
> + tunnel = true;
> else
> return NF_ACCEPT;
> }
> @@ -1767,11 +1772,11 @@ static int ipvs_gre_decap(struct netns_ipvs *ipvs, struct sk_buff *skb,
> "Checking incoming ICMP for");
>
> offset2 = offset;
> - ip_vs_fill_iph_skb_icmp(AF_INET, skb, offset, !ipip, &ciph);
> + ip_vs_fill_iph_skb_icmp(AF_INET, skb, offset, !tunnel, &ciph);
> offset = ciph.len;
>
> /* The embedded headers contain source and dest in reverse order.
> - * For IPIP this is error for request, not for reply.
> + * For IPIP/UDP/GRE tunnel this is error for request, not for reply.
> */
> cp = INDIRECT_CALL_1(pp->conn_in_get, ip_vs_conn_in_get_proto,
> ipvs, AF_INET, skb, &ciph);
> @@ -1779,7 +1784,7 @@ static int ipvs_gre_decap(struct netns_ipvs *ipvs, struct sk_buff *skb,
> if (!cp) {
> int v;
>
> - if (ipip || !sysctl_schedule_icmp(ipvs))
> + if (tunnel || !sysctl_schedule_icmp(ipvs))
> return NF_ACCEPT;
>
> if (!ip_vs_try_to_schedule(ipvs, AF_INET, skb, pd, &v, &cp, &ciph))
> @@ -1797,7 +1802,7 @@ static int ipvs_gre_decap(struct netns_ipvs *ipvs, struct sk_buff *skb,
> goto out;
> }
>
> - if (ipip) {
> + if (tunnel) {
> __be32 info = ic->un.gateway;
> __u8 type = ic->type;
> __u8 code = ic->code;
> @@ -1809,17 +1814,18 @@ static int ipvs_gre_decap(struct netns_ipvs *ipvs, struct sk_buff *skb,
> u32 mtu = ntohs(ic->un.frag.mtu);
> __be16 frag_off = cih->frag_off;
>
> - /* Strip outer IP and ICMP, go to IPIP header */
> + /* Strip outer IP and ICMP, go to IPIP/UDP/GRE header */
> if (pskb_pull(skb, ihl + sizeof(_icmph)) == NULL)
> - goto ignore_ipip;
> + goto ignore_tunnel;
> offset2 -= ihl + sizeof(_icmph);
> skb_reset_network_header(skb);
> - IP_VS_DBG(12, "ICMP for IPIP %pI4->%pI4: mtu=%u\n",
> - &ip_hdr(skb)->saddr, &ip_hdr(skb)->daddr, mtu);
> + IP_VS_DBG(12, "ICMP for %s %pI4->%pI4: mtu=%u\n",
> + outer_proto, &ip_hdr(skb)->saddr,
> + &ip_hdr(skb)->daddr, mtu);
> ipv4_update_pmtu(skb, ipvs->net, mtu, 0, 0);
> /* Client uses PMTUD? */
> if (!(frag_off & htons(IP_DF)))
> - goto ignore_ipip;
> + goto ignore_tunnel;
> /* Prefer the resulting PMTU */
> if (dest) {
> struct ip_vs_dest_dst *dest_dst;
> @@ -1832,11 +1838,11 @@ static int ipvs_gre_decap(struct netns_ipvs *ipvs, struct sk_buff *skb,
> mtu -= sizeof(struct iphdr);
> info = htonl(mtu);
> }
> - /* Strip outer IP, ICMP and IPIP, go to IP header of
> + /* Strip outer IP, ICMP and IPIP/UDP/GRE, go to IP header of
> * original request.
> */
> if (pskb_pull(skb, offset2) == NULL)
> - goto ignore_ipip;
> + goto ignore_tunnel;
> skb_reset_network_header(skb);
> IP_VS_DBG(12, "Sending ICMP for %pI4->%pI4: t=%u, c=%u, i=%u\n",
> &ip_hdr(skb)->saddr, &ip_hdr(skb)->daddr,
> @@ -1845,7 +1851,7 @@ static int ipvs_gre_decap(struct netns_ipvs *ipvs, struct sk_buff *skb,
> /* ICMP can be shorter but anyways, account it */
> ip_vs_out_stats(cp, skb);
>
> -ignore_ipip:
> +ignore_tunnel:
> consume_skb(skb);
> verdict = NF_STOLEN;
> goto out;
> --
> 1.8.3.1
Regards
--
Julian Anastasov <ja@xxxxxx>