From 6f7b841bc939e7c811ad32427b58d54edbcfa6ed Mon Sep 17 00:00:00 2001 From: Vadim Fedorenko Date: Mon, 1 Jul 2019 19:49:34 +0300 Subject: [PATCH] ipvs: allow tunneling with gre encapsulation windows real servers can handle gre tunnels, this patch allows gre encapsulation with the tunneling method, thereby letting ipvs be load balancer for windows-based services Signed-off-by: Vadim Fedorenko Acked-by: Julian Anastasov Signed-off-by: Simon Horman Signed-off-by: Pablo Neira Ayuso --- include/uapi/linux/ip_vs.h | 1 + net/netfilter/ipvs/ip_vs_ctl.c | 1 + net/netfilter/ipvs/ip_vs_xmit.c | 66 +++++++++++++++++++++++++++++++-- 3 files changed, 65 insertions(+), 3 deletions(-) diff --git a/include/uapi/linux/ip_vs.h b/include/uapi/linux/ip_vs.h index e4f18061a4fd..4102ddcb4e14 100644 --- a/include/uapi/linux/ip_vs.h +++ b/include/uapi/linux/ip_vs.h @@ -128,6 +128,7 @@ enum { IP_VS_CONN_F_TUNNEL_TYPE_IPIP = 0, /* IPIP */ IP_VS_CONN_F_TUNNEL_TYPE_GUE, /* GUE */ + IP_VS_CONN_F_TUNNEL_TYPE_GRE, /* GRE */ IP_VS_CONN_F_TUNNEL_TYPE_MAX, }; diff --git a/net/netfilter/ipvs/ip_vs_ctl.c b/net/netfilter/ipvs/ip_vs_ctl.c index 84384d896e29..998353bec74f 100644 --- a/net/netfilter/ipvs/ip_vs_ctl.c +++ b/net/netfilter/ipvs/ip_vs_ctl.c @@ -525,6 +525,7 @@ static void ip_vs_rs_hash(struct netns_ipvs *ipvs, struct ip_vs_dest *dest) port = dest->tun_port; break; case IP_VS_CONN_F_TUNNEL_TYPE_IPIP: + case IP_VS_CONN_F_TUNNEL_TYPE_GRE: port = 0; break; default: diff --git a/net/netfilter/ipvs/ip_vs_xmit.c b/net/netfilter/ipvs/ip_vs_xmit.c index 71fc6d63a67f..9c464d24beec 100644 --- a/net/netfilter/ipvs/ip_vs_xmit.c +++ b/net/netfilter/ipvs/ip_vs_xmit.c @@ -29,6 +29,7 @@ #include /* for tcphdr */ #include #include +#include #include /* for csum_tcpudp_magic */ #include #include /* for icmp_send */ @@ -388,6 +389,12 @@ __ip_vs_get_out_rt(struct netns_ipvs *ipvs, int skb_af, struct sk_buff *skb, IP_VS_TUNNEL_ENCAP_FLAG_REMCSUM) && skb->ip_summed == CHECKSUM_PARTIAL) mtu -= GUE_PLEN_REMCSUM + GUE_LEN_PRIV; + } else if (dest->tun_type == IP_VS_CONN_F_TUNNEL_TYPE_GRE) { + __be16 tflags = 0; + + if (dest->tun_flags & IP_VS_TUNNEL_ENCAP_FLAG_CSUM) + tflags |= TUNNEL_CSUM; + mtu -= gre_calc_hlen(tflags); } if (mtu < 68) { IP_VS_DBG_RL("%s(): mtu less than 68\n", __func__); @@ -548,6 +555,12 @@ __ip_vs_get_out_rt_v6(struct netns_ipvs *ipvs, int skb_af, struct sk_buff *skb, IP_VS_TUNNEL_ENCAP_FLAG_REMCSUM) && skb->ip_summed == CHECKSUM_PARTIAL) mtu -= GUE_PLEN_REMCSUM + GUE_LEN_PRIV; + } else if (dest->tun_type == IP_VS_CONN_F_TUNNEL_TYPE_GRE) { + __be16 tflags = 0; + + if (dest->tun_flags & IP_VS_TUNNEL_ENCAP_FLAG_CSUM) + tflags |= TUNNEL_CSUM; + mtu -= gre_calc_hlen(tflags); } if (mtu < IPV6_MIN_MTU) { IP_VS_DBG_RL("%s(): mtu less than %d\n", __func__, @@ -1079,6 +1092,24 @@ ipvs_gue_encap(struct net *net, struct sk_buff *skb, return 0; } +static void +ipvs_gre_encap(struct net *net, struct sk_buff *skb, + struct ip_vs_conn *cp, __u8 *next_protocol) +{ + __be16 proto = *next_protocol == IPPROTO_IPIP ? + htons(ETH_P_IP) : htons(ETH_P_IPV6); + __be16 tflags = 0; + size_t hdrlen; + + if (cp->dest->tun_flags & IP_VS_TUNNEL_ENCAP_FLAG_CSUM) + tflags |= TUNNEL_CSUM; + + hdrlen = gre_calc_hlen(tflags); + gre_build_header(skb, hdrlen, tflags, proto, 0, 0); + + *next_protocol = IPPROTO_GRE; +} + /* * IP Tunneling transmitter * @@ -1151,6 +1182,15 @@ ip_vs_tunnel_xmit(struct sk_buff *skb, struct ip_vs_conn *cp, gue_hdrlen = sizeof(struct guehdr) + gue_optlen; max_headroom += sizeof(struct udphdr) + gue_hdrlen; + } else if (tun_type == IP_VS_CONN_F_TUNNEL_TYPE_GRE) { + size_t gre_hdrlen; + __be16 tflags = 0; + + if (tun_flags & IP_VS_TUNNEL_ENCAP_FLAG_CSUM) + tflags |= TUNNEL_CSUM; + gre_hdrlen = gre_calc_hlen(tflags); + + max_headroom += gre_hdrlen; } /* We only care about the df field if sysctl_pmtu_disc(ipvs) is set */ @@ -1172,6 +1212,11 @@ ip_vs_tunnel_xmit(struct sk_buff *skb, struct ip_vs_conn *cp, skb->ip_summed == CHECKSUM_PARTIAL) { gso_type |= SKB_GSO_TUNNEL_REMCSUM; } + } else if (tun_type == IP_VS_CONN_F_TUNNEL_TYPE_GRE) { + if (tun_flags & IP_VS_TUNNEL_ENCAP_FLAG_CSUM) + gso_type |= SKB_GSO_GRE_CSUM; + else + gso_type |= SKB_GSO_GRE; } if (iptunnel_handle_offloads(skb, gso_type)) @@ -1192,8 +1237,8 @@ ip_vs_tunnel_xmit(struct sk_buff *skb, struct ip_vs_conn *cp, check = true; udp_set_csum(!check, skb, saddr, cp->daddr.ip, skb->len); - } - + } else if (tun_type == IP_VS_CONN_F_TUNNEL_TYPE_GRE) + ipvs_gre_encap(net, skb, cp, &next_protocol); skb_push(skb, sizeof(struct iphdr)); skb_reset_network_header(skb); @@ -1287,6 +1332,15 @@ ip_vs_tunnel_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp, gue_hdrlen = sizeof(struct guehdr) + gue_optlen; max_headroom += sizeof(struct udphdr) + gue_hdrlen; + } else if (tun_type == IP_VS_CONN_F_TUNNEL_TYPE_GRE) { + size_t gre_hdrlen; + __be16 tflags = 0; + + if (tun_flags & IP_VS_TUNNEL_ENCAP_FLAG_CSUM) + tflags |= TUNNEL_CSUM; + gre_hdrlen = gre_calc_hlen(tflags); + + max_headroom += gre_hdrlen; } skb = ip_vs_prepare_tunneled_skb(skb, cp->af, max_headroom, @@ -1306,6 +1360,11 @@ ip_vs_tunnel_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp, skb->ip_summed == CHECKSUM_PARTIAL) { gso_type |= SKB_GSO_TUNNEL_REMCSUM; } + } else if (tun_type == IP_VS_CONN_F_TUNNEL_TYPE_GRE) { + if (tun_flags & IP_VS_TUNNEL_ENCAP_FLAG_CSUM) + gso_type |= SKB_GSO_GRE_CSUM; + else + gso_type |= SKB_GSO_GRE; } if (iptunnel_handle_offloads(skb, gso_type)) @@ -1326,7 +1385,8 @@ ip_vs_tunnel_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp, check = true; udp6_set_csum(!check, skb, &saddr, &cp->daddr.in6, skb->len); - } + } else if (tun_type == IP_VS_CONN_F_TUNNEL_TYPE_GRE) + ipvs_gre_encap(net, skb, cp, &next_protocol); skb_push(skb, sizeof(struct ipv6hdr)); skb_reset_network_header(skb); -- 2.30.2