Pull the common logic for preparing an skb to prepend the header into a single function and then set fields such that they can be used in either case (generalize tos and tclass to dscp, hop_limit and ttl to ttl, etc) Signed-off-by: Alex Gartrell <agartrell@xxxxxx> --- net/netfilter/ipvs/ip_vs_conn.c | 12 +++- net/netfilter/ipvs/ip_vs_xmit.c | 135 ++++++++++++++++++++++++++-------------- 2 files changed, 100 insertions(+), 47 deletions(-) diff --git a/net/netfilter/ipvs/ip_vs_conn.c b/net/netfilter/ipvs/ip_vs_conn.c index 22c72da..86ecb14 100644 --- a/net/netfilter/ipvs/ip_vs_conn.c +++ b/net/netfilter/ipvs/ip_vs_conn.c @@ -488,7 +488,12 @@ static inline void ip_vs_bind_xmit(struct ip_vs_conn *cp) break; case IP_VS_CONN_F_TUNNEL: - cp->packet_xmit = ip_vs_tunnel_xmit; +#ifdef CONFIG_IP_VS_IPV6 + if (cp->dest->af == AF_INET6) + cp->packet_xmit = ip_vs_tunnel_xmit_v6; + else +#endif + cp->packet_xmit = ip_vs_tunnel_xmit; break; case IP_VS_CONN_F_DROUTE: @@ -514,7 +519,10 @@ static inline void ip_vs_bind_xmit_v6(struct ip_vs_conn *cp) break; case IP_VS_CONN_F_TUNNEL: - cp->packet_xmit = ip_vs_tunnel_xmit_v6; + if (cp->dest->af == AF_INET6) + cp->packet_xmit = ip_vs_tunnel_xmit_v6; + else + cp->packet_xmit = ip_vs_tunnel_xmit; break; case IP_VS_CONN_F_DROUTE: diff --git a/net/netfilter/ipvs/ip_vs_xmit.c b/net/netfilter/ipvs/ip_vs_xmit.c index 9c68089..2c5097f 100644 --- a/net/netfilter/ipvs/ip_vs_xmit.c +++ b/net/netfilter/ipvs/ip_vs_xmit.c @@ -790,6 +790,66 @@ tx_error: } #endif +/* When forwarding a packet, we must ensure that we've got enough headroom + * for the encapsulation packet in the skb. This also gives us an + * opportunity to figure out what the payload_len, dsfield, ttl, and df + * values should be, so that we won't need to look at the old ip header + * again */ +static struct sk_buff * +ip_vs_prepare_tunneled_skb(struct sk_buff *skb, unsigned int max_headroom, + __u8 *next_protocol, __u32 *payload_len, __u8 *dsfield, + __u8 *ttl, __be16 *df) +{ + struct sk_buff *out_skb = NULL; + __u8 version = ip_hdr(skb)->version; + struct iphdr *old_iph = NULL; +#ifdef CONFIG_IP_VS_IPV6 + struct ipv6hdr *old_ipv6h = NULL; +#endif + + if (skb_headroom(skb) < max_headroom || skb_cloned(skb)) { + out_skb = skb_realloc_headroom(skb, max_headroom); + if (!out_skb) + return NULL; + consume_skb(skb); + } else + out_skb = skb; + +#ifdef CONFIG_IP_VS_IPV6 + if (version == 6) { + old_ipv6h = ipv6_hdr(skb); + *next_protocol = IPPROTO_IPV6; + if (payload_len) + *payload_len = + ntohs(old_ipv6h->payload_len) + sizeof(*old_ipv6h); + *dsfield = ipv6_get_dsfield(old_ipv6h); + *ttl = old_ipv6h->hop_limit; + if (df) + *df = 0; + } else +#endif + { + old_iph = ip_hdr(out_skb); + /* Copy DF, reset fragment offset and MF */ + if (df) + *df = (old_iph->frag_off & htons(IP_DF)); + *next_protocol = IPPROTO_IPIP; + + /* fix old IP header checksum */ + ip_send_check(old_iph); + *dsfield = ipv4_get_dsfield(old_iph); + *ttl = old_iph->ttl; + if (payload_len) + *payload_len = ntohs(old_iph->tot_len); + } + + /* We are about to encapsulate the ip header, which breaks hardware + * checksum offload. Let's call skb_checksum_help to finish up any + * partial checksums */ + skb_checksum_help(skb); + + return out_skb; +} /* * IP Tunneling transmitter @@ -818,11 +878,14 @@ ip_vs_tunnel_xmit(struct sk_buff *skb, struct ip_vs_conn *cp, struct rtable *rt; /* Route to the other host */ __be32 saddr; /* Source for tunnel */ struct net_device *tdev; /* Device to other host */ - struct iphdr *old_iph = ip_hdr(skb); - u8 tos = old_iph->tos; - __be16 df; + __u8 next_protocol = 0; + __u8 dsfield = 0; + __u8 ttl = 0; + __be16 df = 0; + __be16 *dfp = NULL; struct iphdr *iph; /* Our new IP header */ unsigned int max_headroom; /* The extra header space needed */ + struct sk_buff *out_skb = NULL; int ret, local; EnterFunction(10); @@ -843,29 +906,18 @@ ip_vs_tunnel_xmit(struct sk_buff *skb, struct ip_vs_conn *cp, rt = skb_rtable(skb); tdev = rt->dst.dev; - /* Copy DF, reset fragment offset and MF */ - df = sysctl_pmtu_disc(ipvs) ? old_iph->frag_off & htons(IP_DF) : 0; - /* * Okay, now see if we can stuff it in the buffer as-is. */ max_headroom = LL_RESERVED_SPACE(tdev) + sizeof(struct iphdr); - if (skb_headroom(skb) < max_headroom || skb_cloned(skb)) { - struct sk_buff *new_skb = - skb_realloc_headroom(skb, max_headroom); - - if (!new_skb) - goto tx_error; - consume_skb(skb); - skb = new_skb; - old_iph = ip_hdr(skb); - } - - /* We are about to encapsulate the ip header, which breaks hardware - * checksum offload. Let's call skb_checksum_help to finish up any - * partial checksums */ - skb_checksum_help(skb); + /* We only care about the df field is sysctl_pmtu_disc(ipvs) is set */ + dfp = sysctl_pmtu_disc(ipvs) ? &df : NULL; + out_skb = ip_vs_prepare_tunneled_skb(skb, max_headroom, &next_protocol, + NULL, &dsfield, &ttl, dfp); + if (!out_skb) + goto tx_error; + skb = out_skb; skb->transport_header = skb->network_header; @@ -880,11 +932,11 @@ ip_vs_tunnel_xmit(struct sk_buff *skb, struct ip_vs_conn *cp, iph->version = 4; iph->ihl = sizeof(struct iphdr)>>2; iph->frag_off = df; - iph->protocol = IPPROTO_IPIP; - iph->tos = tos; + iph->protocol = next_protocol; + iph->tos = dsfield; iph->daddr = cp->daddr.ip; iph->saddr = saddr; - iph->ttl = old_iph->ttl; + iph->ttl = ttl; ip_select_ident(skb, NULL); /* Another hack: avoid icmp_send in ip_fragment */ @@ -916,9 +968,13 @@ ip_vs_tunnel_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp, struct rt6_info *rt; /* Route to the other host */ struct in6_addr saddr; /* Source for tunnel */ struct net_device *tdev; /* Device to other host */ - struct ipv6hdr *old_iph = ipv6_hdr(skb); + __u8 next_protocol = 0; + __u32 payload_len = 0; + __u8 dsfield = 0; + __u8 ttl = 0; struct ipv6hdr *iph; /* Our new IP header */ unsigned int max_headroom; /* The extra header space needed */ + struct sk_buff *out_skb = NULL; int ret, local; EnterFunction(10); @@ -944,21 +1000,11 @@ ip_vs_tunnel_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp, */ max_headroom = LL_RESERVED_SPACE(tdev) + sizeof(struct ipv6hdr); - if (skb_headroom(skb) < max_headroom || skb_cloned(skb)) { - struct sk_buff *new_skb = - skb_realloc_headroom(skb, max_headroom); - - if (!new_skb) - goto tx_error; - consume_skb(skb); - skb = new_skb; - old_iph = ipv6_hdr(skb); - } - - /* We are about to encapsulate the ip header, which breaks hardware - * checksum offload. Let's call skb_checksum_help to finish up any - * partial checksums */ - skb_checksum_help(skb); + out_skb = ip_vs_prepare_tunneled_skb(skb, max_headroom, &next_protocol, + &payload_len, &dsfield, &ttl, NULL); + if (!out_skb) + goto tx_error; + skb = out_skb; skb->transport_header = skb->network_header; @@ -971,14 +1017,13 @@ ip_vs_tunnel_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp, */ iph = ipv6_hdr(skb); iph->version = 6; - iph->nexthdr = IPPROTO_IPV6; - iph->payload_len = old_iph->payload_len; - be16_add_cpu(&iph->payload_len, sizeof(*old_iph)); + iph->nexthdr = next_protocol; + iph->payload_len = ntohs(payload_len); memset(&iph->flow_lbl, 0, sizeof(iph->flow_lbl)); - ipv6_change_dsfield(iph, 0, ipv6_get_dsfield(old_iph)); + ipv6_change_dsfield(iph, 0, dsfield); iph->daddr = cp->daddr.in6; iph->saddr = saddr; - iph->hop_limit = old_iph->hop_limit; + iph->hop_limit = ttl; /* Another hack: avoid icmp_send in ip_fragment */ skb->ignore_df = 1; -- 1.8.1 -- To unsubscribe from this list: send the line "unsubscribe lvs-devel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html