ipvs: add checksum support for gue encapsulation

Add checksum support for gue encapsulation with the tun_flags parameter,
which could be one of the values below:
IP_VS_TUNNEL_ENCAP_FLAG_NOCSUM
IP_VS_TUNNEL_ENCAP_FLAG_CSUM
IP_VS_TUNNEL_ENCAP_FLAG_REMCSUM

Signed-off-by: Jacky Hu <hengqing.hu@gmail.com>
Signed-off-by: Julian Anastasov <ja@ssi.bg>
Signed-off-by: Simon Horman <horms@verge.net.au>
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>

diff --git a/include/net/ip_vs.h b/include/net/ip_vs.h
index b01a94ebfc0e8f197581d960151df7fbd7c2a1a8..cb1ad0cc5c7be23ecf1ce6f985ea404730e5b1d9 100644 (file)
--- a/include/net/ip_vs.h
+++ b/include/net/ip_vs.h
@@ -603,6 +603,7 @@ struct ip_vs_dest_user_kern {
 
        u16                     tun_type;       /* tunnel type */
        __be16                  tun_port;       /* tunnel port */
+       u16                     tun_flags;      /* tunnel flags */
 };
 
 
@@ -665,6 +666,7 @@ struct ip_vs_dest {
        atomic_t                last_weight;    /* server latest weight */
        __u16                   tun_type;       /* tunnel type */
        __be16                  tun_port;       /* tunnel port */
+       __u16                   tun_flags;      /* tunnel flags */
 
        refcount_t              refcnt;         /* reference counter */
        struct ip_vs_stats      stats;          /* statistics */

diff --git a/include/uapi/linux/ip_vs.h b/include/uapi/linux/ip_vs.h
index e34f436fc79d35f7d5930e11ef5176bb088ecd9b..e4f18061a4fd3e02d03a19c0341bac55cd15e8fd 100644 (file)
--- a/include/uapi/linux/ip_vs.h
+++ b/include/uapi/linux/ip_vs.h
@@ -131,6 +131,11 @@ enum {
        IP_VS_CONN_F_TUNNEL_TYPE_MAX,
 };
 
+/* Tunnel encapsulation flags */
+#define IP_VS_TUNNEL_ENCAP_FLAG_NOCSUM         (0)
+#define IP_VS_TUNNEL_ENCAP_FLAG_CSUM           (1 << 0)
+#define IP_VS_TUNNEL_ENCAP_FLAG_REMCSUM                (1 << 1)
+
 /*
  *     The struct ip_vs_service_user and struct ip_vs_dest_user are
  *     used to set IPVS rules through setsockopt.
@@ -403,6 +408,8 @@ enum {
 
        IPVS_DEST_ATTR_TUN_PORT,        /* tunnel port */
 
+       IPVS_DEST_ATTR_TUN_FLAGS,       /* tunnel flags */
+
        __IPVS_DEST_ATTR_MAX,
 };
 

diff --git a/net/netfilter/ipvs/ip_vs_ctl.c b/net/netfilter/ipvs/ip_vs_ctl.c
index d5847e06350f65a2a454561c21cef0cba973d6ef..ad19ac08622fa1858f3700c15d2d2120c5ec679b 100644 (file)
--- a/net/netfilter/ipvs/ip_vs_ctl.c
+++ b/net/netfilter/ipvs/ip_vs_ctl.c
@@ -893,6 +893,7 @@ __ip_vs_update_dest(struct ip_vs_service *svc, struct ip_vs_dest *dest,
        /* set the tunnel info */
        dest->tun_type = udest->tun_type;
        dest->tun_port = udest->tun_port;
+       dest->tun_flags = udest->tun_flags;
 
        /* set the IP_VS_CONN_F_NOOUTPUT flag if not masquerading/NAT */
        if ((conn_flags & IP_VS_CONN_F_FWD_MASK) != IP_VS_CONN_F_MASQ) {
@@ -2967,6 +2968,7 @@ static const struct nla_policy ip_vs_dest_policy[IPVS_DEST_ATTR_MAX + 1] = {
        [IPVS_DEST_ATTR_ADDR_FAMILY]    = { .type = NLA_U16 },
        [IPVS_DEST_ATTR_TUN_TYPE]       = { .type = NLA_U8 },
        [IPVS_DEST_ATTR_TUN_PORT]       = { .type = NLA_U16 },
+       [IPVS_DEST_ATTR_TUN_FLAGS]      = { .type = NLA_U16 },
 };
 
 static int ip_vs_genl_fill_stats(struct sk_buff *skb, int container_type,
@@ -3273,6 +3275,8 @@ static int ip_vs_genl_fill_dest(struct sk_buff *skb, struct ip_vs_dest *dest)
                       dest->tun_type) ||
            nla_put_be16(skb, IPVS_DEST_ATTR_TUN_PORT,
                         dest->tun_port) ||
+           nla_put_u16(skb, IPVS_DEST_ATTR_TUN_FLAGS,
+                       dest->tun_flags) ||
            nla_put_u32(skb, IPVS_DEST_ATTR_U_THRESH, dest->u_threshold) ||
            nla_put_u32(skb, IPVS_DEST_ATTR_L_THRESH, dest->l_threshold) ||
            nla_put_u32(skb, IPVS_DEST_ATTR_ACTIVE_CONNS,
@@ -3393,7 +3397,8 @@ static int ip_vs_genl_parse_dest(struct ip_vs_dest_user_kern *udest,
        /* If a full entry was requested, check for the additional fields */
        if (full_entry) {
                struct nlattr *nla_fwd, *nla_weight, *nla_u_thresh,
-                             *nla_l_thresh, *nla_tun_type, *nla_tun_port;
+                             *nla_l_thresh, *nla_tun_type, *nla_tun_port,
+                             *nla_tun_flags;
 
                nla_fwd         = attrs[IPVS_DEST_ATTR_FWD_METHOD];
                nla_weight      = attrs[IPVS_DEST_ATTR_WEIGHT];
@@ -3401,6 +3406,7 @@ static int ip_vs_genl_parse_dest(struct ip_vs_dest_user_kern *udest,
                nla_l_thresh    = attrs[IPVS_DEST_ATTR_L_THRESH];
                nla_tun_type    = attrs[IPVS_DEST_ATTR_TUN_TYPE];
                nla_tun_port    = attrs[IPVS_DEST_ATTR_TUN_PORT];
+               nla_tun_flags   = attrs[IPVS_DEST_ATTR_TUN_FLAGS];
 
                if (!(nla_fwd && nla_weight && nla_u_thresh && nla_l_thresh))
                        return -EINVAL;
@@ -3416,6 +3422,9 @@ static int ip_vs_genl_parse_dest(struct ip_vs_dest_user_kern *udest,
 
                if (nla_tun_port)
                        udest->tun_port = nla_get_be16(nla_tun_port);
+
+               if (nla_tun_flags)
+                       udest->tun_flags = nla_get_u16(nla_tun_flags);
        }
 
        return 0;

diff --git a/net/netfilter/ipvs/ip_vs_xmit.c b/net/netfilter/ipvs/ip_vs_xmit.c
index 0b41d0504429731dcdaf1893334eacd275103423..af3379d5e5bc20a0053d269eba46f6a118d2277d 100644 (file)
--- a/net/netfilter/ipvs/ip_vs_xmit.c
+++ b/net/netfilter/ipvs/ip_vs_xmit.c
@@ -40,6 +40,7 @@
 #include <net/ipv6.h>
 #include <net/ip6_route.h>
 #include <net/ip_tunnels.h>
+#include <net/ip6_checksum.h>
 #include <net/addrconf.h>
 #include <linux/icmpv6.h>
 #include <linux/netfilter.h>
@@ -385,8 +386,13 @@ __ip_vs_get_out_rt(struct netns_ipvs *ipvs, int skb_af, struct sk_buff *skb,
                mtu = dst_mtu(&rt->dst) - sizeof(struct iphdr);
                if (!dest)
                        goto err_put;
-               if (dest->tun_type == IP_VS_CONN_F_TUNNEL_TYPE_GUE)
+               if (dest->tun_type == IP_VS_CONN_F_TUNNEL_TYPE_GUE) {
                        mtu -= sizeof(struct udphdr) + sizeof(struct guehdr);
+                       if ((dest->tun_flags &
+                            IP_VS_TUNNEL_ENCAP_FLAG_REMCSUM) &&
+                           skb->ip_summed == CHECKSUM_PARTIAL)
+                               mtu -= GUE_PLEN_REMCSUM + GUE_LEN_PRIV;
+               }
                if (mtu < 68) {
                        IP_VS_DBG_RL("%s(): mtu less than 68\n", __func__);
                        goto err_put;
@@ -540,8 +546,13 @@ __ip_vs_get_out_rt_v6(struct netns_ipvs *ipvs, int skb_af, struct sk_buff *skb,
                mtu = dst_mtu(&rt->dst) - sizeof(struct ipv6hdr);
                if (!dest)
                        goto err_put;
-               if (dest->tun_type == IP_VS_CONN_F_TUNNEL_TYPE_GUE)
+               if (dest->tun_type == IP_VS_CONN_F_TUNNEL_TYPE_GUE) {
                        mtu -= sizeof(struct udphdr) + sizeof(struct guehdr);
+                       if ((dest->tun_flags &
+                            IP_VS_TUNNEL_ENCAP_FLAG_REMCSUM) &&
+                           skb->ip_summed == CHECKSUM_PARTIAL)
+                               mtu -= GUE_PLEN_REMCSUM + GUE_LEN_PRIV;
+               }
                if (mtu < IPV6_MIN_MTU) {
                        IP_VS_DBG_RL("%s(): mtu less than %d\n", __func__,
                                     IPV6_MIN_MTU);
@@ -1006,17 +1017,56 @@ ipvs_gue_encap(struct net *net, struct sk_buff *skb,
        __be16 sport = udp_flow_src_port(net, skb, 0, 0, false);
        struct udphdr  *udph;   /* Our new UDP header */
        struct guehdr  *gueh;   /* Our new GUE header */
+       size_t hdrlen, optlen = 0;
+       void *data;
+       bool need_priv = false;
+
+       if ((cp->dest->tun_flags & IP_VS_TUNNEL_ENCAP_FLAG_REMCSUM) &&
+           skb->ip_summed == CHECKSUM_PARTIAL) {
+               optlen += GUE_PLEN_REMCSUM + GUE_LEN_PRIV;
+               need_priv = true;
+       }
 
-       skb_push(skb, sizeof(struct guehdr));
+       hdrlen = sizeof(struct guehdr) + optlen;
+
+       skb_push(skb, hdrlen);
 
        gueh = (struct guehdr *)skb->data;
 
        gueh->control = 0;
        gueh->version = 0;
-       gueh->hlen = 0;
+       gueh->hlen = optlen >> 2;
        gueh->flags = 0;
        gueh->proto_ctype = *next_protocol;
 
+       data = &gueh[1];
+
+       if (need_priv) {
+               __be32 *flags = data;
+               u16 csum_start = skb_checksum_start_offset(skb);
+               __be16 *pd;
+
+               gueh->flags |= GUE_FLAG_PRIV;
+               *flags = 0;
+               data += GUE_LEN_PRIV;
+
+               if (csum_start < hdrlen)
+                       return -EINVAL;
+
+               csum_start -= hdrlen;
+               pd = data;
+               pd[0] = htons(csum_start);
+               pd[1] = htons(csum_start + skb->csum_offset);
+
+               if (!skb_is_gso(skb)) {
+                       skb->ip_summed = CHECKSUM_NONE;
+                       skb->encapsulation = 0;
+               }
+
+               *flags |= GUE_PFLAG_REMCSUM;
+               data += GUE_PLEN_REMCSUM;
+       }
+
        skb_push(skb, sizeof(struct udphdr));
        skb_reset_transport_header(skb);
 
@@ -1070,6 +1120,7 @@ ip_vs_tunnel_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
        unsigned int max_headroom;              /* The extra header space needed */
        int ret, local;
        int tun_type, gso_type;
+       int tun_flags;
 
        EnterFunction(10);
 
@@ -1092,9 +1143,19 @@ ip_vs_tunnel_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
        max_headroom = LL_RESERVED_SPACE(tdev) + sizeof(struct iphdr);
 
        tun_type = cp->dest->tun_type;
+       tun_flags = cp->dest->tun_flags;
 
-       if (tun_type == IP_VS_CONN_F_TUNNEL_TYPE_GUE)
-               max_headroom += sizeof(struct udphdr) + sizeof(struct guehdr);
+       if (tun_type == IP_VS_CONN_F_TUNNEL_TYPE_GUE) {
+               size_t gue_hdrlen, gue_optlen = 0;
+
+               if ((tun_flags & IP_VS_TUNNEL_ENCAP_FLAG_REMCSUM) &&
+                   skb->ip_summed == CHECKSUM_PARTIAL) {
+                       gue_optlen += GUE_PLEN_REMCSUM + GUE_LEN_PRIV;
+               }
+               gue_hdrlen = sizeof(struct guehdr) + gue_optlen;
+
+               max_headroom += sizeof(struct udphdr) + gue_hdrlen;
+       }
 
        /* We only care about the df field if sysctl_pmtu_disc(ipvs) is set */
        dfp = sysctl_pmtu_disc(ipvs) ? &df : NULL;
@@ -1105,8 +1166,17 @@ ip_vs_tunnel_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
                goto tx_error;
 
        gso_type = __tun_gso_type_mask(AF_INET, cp->af);
-       if (tun_type == IP_VS_CONN_F_TUNNEL_TYPE_GUE)
-               gso_type |= SKB_GSO_UDP_TUNNEL;
+       if (tun_type == IP_VS_CONN_F_TUNNEL_TYPE_GUE) {
+               if ((tun_flags & IP_VS_TUNNEL_ENCAP_FLAG_CSUM) ||
+                   (tun_flags & IP_VS_TUNNEL_ENCAP_FLAG_REMCSUM))
+                       gso_type |= SKB_GSO_UDP_TUNNEL_CSUM;
+               else
+                       gso_type |= SKB_GSO_UDP_TUNNEL;
+               if ((tun_flags & IP_VS_TUNNEL_ENCAP_FLAG_REMCSUM) &&
+                   skb->ip_summed == CHECKSUM_PARTIAL) {
+                       gso_type |= SKB_GSO_TUNNEL_REMCSUM;
+               }
+       }
 
        if (iptunnel_handle_offloads(skb, gso_type))
                goto tx_error;
@@ -1115,8 +1185,19 @@ ip_vs_tunnel_xmit(struct sk_buff *skb, struct ip_vs_conn *cp,
 
        skb_set_inner_ipproto(skb, next_protocol);
 
-       if (tun_type == IP_VS_CONN_F_TUNNEL_TYPE_GUE)
-               ipvs_gue_encap(net, skb, cp, &next_protocol);
+       if (tun_type == IP_VS_CONN_F_TUNNEL_TYPE_GUE) {
+               bool check = false;
+
+               if (ipvs_gue_encap(net, skb, cp, &next_protocol))
+                       goto tx_error;
+
+               if ((tun_flags & IP_VS_TUNNEL_ENCAP_FLAG_CSUM) ||
+                   (tun_flags & IP_VS_TUNNEL_ENCAP_FLAG_REMCSUM))
+                       check = true;
+
+               udp_set_csum(!check, skb, saddr, cp->daddr.ip, skb->len);
+       }
+
 
        skb_push(skb, sizeof(struct iphdr));
        skb_reset_network_header(skb);
@@ -1174,6 +1255,7 @@ ip_vs_tunnel_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
        unsigned int max_headroom;      /* The extra header space needed */
        int ret, local;
        int tun_type, gso_type;
+       int tun_flags;
 
        EnterFunction(10);
 
@@ -1197,9 +1279,19 @@ ip_vs_tunnel_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
        max_headroom = LL_RESERVED_SPACE(tdev) + sizeof(struct ipv6hdr);
 
        tun_type = cp->dest->tun_type;
+       tun_flags = cp->dest->tun_flags;
 
-       if (tun_type == IP_VS_CONN_F_TUNNEL_TYPE_GUE)
-               max_headroom += sizeof(struct udphdr) + sizeof(struct guehdr);
+       if (tun_type == IP_VS_CONN_F_TUNNEL_TYPE_GUE) {
+               size_t gue_hdrlen, gue_optlen = 0;
+
+               if ((tun_flags & IP_VS_TUNNEL_ENCAP_FLAG_REMCSUM) &&
+                   skb->ip_summed == CHECKSUM_PARTIAL) {
+                       gue_optlen += GUE_PLEN_REMCSUM + GUE_LEN_PRIV;
+               }
+               gue_hdrlen = sizeof(struct guehdr) + gue_optlen;
+
+               max_headroom += sizeof(struct udphdr) + gue_hdrlen;
+       }
 
        skb = ip_vs_prepare_tunneled_skb(skb, cp->af, max_headroom,
                                         &next_protocol, &payload_len,
@@ -1208,8 +1300,17 @@ ip_vs_tunnel_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
                goto tx_error;
 
        gso_type = __tun_gso_type_mask(AF_INET6, cp->af);
-       if (tun_type == IP_VS_CONN_F_TUNNEL_TYPE_GUE)
-               gso_type |= SKB_GSO_UDP_TUNNEL;
+       if (tun_type == IP_VS_CONN_F_TUNNEL_TYPE_GUE) {
+               if ((tun_flags & IP_VS_TUNNEL_ENCAP_FLAG_CSUM) ||
+                   (tun_flags & IP_VS_TUNNEL_ENCAP_FLAG_REMCSUM))
+                       gso_type |= SKB_GSO_UDP_TUNNEL_CSUM;
+               else
+                       gso_type |= SKB_GSO_UDP_TUNNEL;
+               if ((tun_flags & IP_VS_TUNNEL_ENCAP_FLAG_REMCSUM) &&
+                   skb->ip_summed == CHECKSUM_PARTIAL) {
+                       gso_type |= SKB_GSO_TUNNEL_REMCSUM;
+               }
+       }
 
        if (iptunnel_handle_offloads(skb, gso_type))
                goto tx_error;
@@ -1218,8 +1319,18 @@ ip_vs_tunnel_xmit_v6(struct sk_buff *skb, struct ip_vs_conn *cp,
 
        skb_set_inner_ipproto(skb, next_protocol);
 
-       if (tun_type == IP_VS_CONN_F_TUNNEL_TYPE_GUE)
-               ipvs_gue_encap(net, skb, cp, &next_protocol);
+       if (tun_type == IP_VS_CONN_F_TUNNEL_TYPE_GUE) {
+               bool check = false;
+
+               if (ipvs_gue_encap(net, skb, cp, &next_protocol))
+                       goto tx_error;
+
+               if ((tun_flags & IP_VS_TUNNEL_ENCAP_FLAG_CSUM) ||
+                   (tun_flags & IP_VS_TUNNEL_ENCAP_FLAG_REMCSUM))
+                       check = true;
+
+               udp6_set_csum(!check, skb, &saddr, &cp->daddr.in6, skb->len);
+       }
 
        skb_push(skb, sizeof(struct ipv6hdr));
        skb_reset_network_header(skb);