[PATCH v1] ipvs: add checksum support for gue encapsulation
From: Jacky Hu
Date: Thu May 23 2019 - 22:55:01 EST
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@xxxxxxxxx>
---
include/net/ip_vs.h | 2 +
include/uapi/linux/ip_vs.h | 7 ++
net/netfilter/ipvs/ip_vs_core.c | 56 +++++++++++++
net/netfilter/ipvs/ip_vs_ctl.c | 11 ++-
net/netfilter/ipvs/ip_vs_xmit.c | 138 ++++++++++++++++++++++++++++----
5 files changed, 198 insertions(+), 16 deletions(-)
diff --git a/include/net/ip_vs.h b/include/net/ip_vs.h
index b01a94ebfc0e..cb1ad0cc5c7b 100644
--- 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 e34f436fc79d..fa5cf8498474 100644
--- 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_core.c b/net/netfilter/ipvs/ip_vs_core.c
index d1d7b2483fd7..85e5ac363b52 100644
--- a/net/netfilter/ipvs/ip_vs_core.c
+++ b/net/netfilter/ipvs/ip_vs_core.c
@@ -1580,6 +1580,29 @@ ip_vs_try_to_schedule(struct netns_ipvs *ipvs, int af, struct sk_buff *skb,
return 1;
}
+static struct guehdr *gue_remcsum(struct sk_buff *skb, struct guehdr *guehdr,
+ void *data, size_t hdrlen, u8 ipproto,
+ bool nopartial)
+{
+ __be16 *pd = data;
+ size_t start = ntohs(pd[0]);
+ size_t offset = ntohs(pd[1]);
+ size_t plen = sizeof(struct udphdr) + hdrlen +
+ max_t(size_t, offset + sizeof(u16), start);
+
+ if (skb->remcsum_offload)
+ return guehdr;
+
+ if (!pskb_may_pull(skb, plen))
+ return NULL;
+ guehdr = (struct guehdr *)&udp_hdr(skb)[1];
+
+ skb_remcsum_process(skb, (void *)guehdr + hdrlen,
+ start, offset, nopartial);
+
+ return guehdr;
+}
+
/* Check the UDP tunnel and return its header length */
static int ipvs_udp_decap(struct netns_ipvs *ipvs, struct sk_buff *skb,
unsigned int offset, __u16 af,
@@ -1597,6 +1620,9 @@ static int ipvs_udp_decap(struct netns_ipvs *ipvs, struct sk_buff *skb,
goto unk;
if (dest->tun_type == IP_VS_CONN_F_TUNNEL_TYPE_GUE) {
struct guehdr _gueh, *gueh;
+ size_t optlen, hdrlen;
+ void *data;
+ u16 doffset = 0;
gueh = skb_header_pointer(skb, offset, sizeof(_gueh), &_gueh);
if (!gueh)
@@ -1606,7 +1632,37 @@ static int ipvs_udp_decap(struct netns_ipvs *ipvs, struct sk_buff *skb,
/* Later we can support also IPPROTO_IPV6 */
if (gueh->proto_ctype != IPPROTO_IPIP)
goto unk;
+
+ optlen = gueh->hlen << 2;
+ hdrlen = sizeof(struct guehdr) + optlen;
+ data = &gueh[1];
+
+ if (gueh->flags & GUE_FLAG_PRIV) {
+ __be32 flags = *(__be32 *)(data + doffset);
+
+ doffset += GUE_LEN_PRIV;
+
+ if (flags & GUE_PFLAG_REMCSUM) {
+ gueh = gue_remcsum(skb, gueh,
+ data + doffset, hdrlen,
+ gueh->proto_ctype,
+ true);
+ if (!gueh)
+ goto unk;
+
+ data = &gueh[1];
+
+ doffset += GUE_PLEN_REMCSUM;
+ }
+ }
+
*proto = gueh->proto_ctype;
+ __skb_pull(skb, sizeof(struct udphdr) + hdrlen);
+ skb_reset_transport_header(skb);
+
+ if (iptunnel_pull_offloads(skb))
+ goto unk;
+
return sizeof(struct udphdr) + sizeof(struct guehdr) +
(gueh->hlen << 2);
}
diff --git a/net/netfilter/ipvs/ip_vs_ctl.c b/net/netfilter/ipvs/ip_vs_ctl.c
index d5847e06350f..d7520179ac67 100644
--- 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_U8 },
};
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_u8(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_u8(nla_tun_flags);
}
return 0;
diff --git a/net/netfilter/ipvs/ip_vs_xmit.c b/net/netfilter/ipvs/ip_vs_xmit.c
index 8d6f94b67772..35fd7e5a9123 100644
--- 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);
@@ -1006,6 +1017,17 @@ 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;
+ }
+
+ hdrlen = sizeof(struct guehdr) + optlen;
skb_push(skb, sizeof(struct guehdr));
@@ -1013,10 +1035,37 @@ ipvs_gue_encap(struct net *net, struct sk_buff *skb,
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 = data;
+
+ gueh->flags |= GUE_FLAG_PRIV;
+ *flags = 0;
+ data += GUE_LEN_PRIV;
+
+ if (csum_start < hdrlen)
+ return -EINVAL;
+
+ csum_start -= hdrlen;
+ 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 +1119,8 @@ 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;
+ size_t gue_hdrlen, gue_optlen = 0;
EnterFunction(10);
@@ -1092,9 +1143,17 @@ 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) {
+ 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 +1164,17 @@ 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 +1183,19 @@ 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 +1253,8 @@ 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;
+ size_t gue_hdrlen, gue_optlen = 0;
EnterFunction(10);
@@ -1197,9 +1278,17 @@ 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) {
+ 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;
- if (tun_type == IP_VS_CONN_F_TUNNEL_TYPE_GUE)
- max_headroom += sizeof(struct udphdr) + sizeof(struct guehdr);
+ max_headroom += sizeof(struct udphdr) + gue_hdrlen;
+ }
skb = ip_vs_prepare_tunneled_skb(skb, cp->af, max_headroom,
&next_protocol, &payload_len,
@@ -1208,8 +1297,17 @@ 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 +1316,18 @@ 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);
--
2.21.0