Merge branch 'inet_csums'

Tom Herbert says:

====================
net: Support checksum in UDP

This patch series adds support for using checksums in UDP tunnels. With
this it is possible that two or more checksums may be set within the
same packet and we would like to do that efficiently.

This series also creates some new helper functions to be used by various
tunnel protocol implementations.

v2: Fixed indentation in tcp_v6_send_check arguments.
v3: Move udp_set_csum and udp6_set_csum to be not inlined
    Also have this functions call with a nocheck boolean argument
    instead of passing a sock structure.
====================

Signed-off-by: David S. Miller <davem@davemloft.net>

1 files changed, 59 insertions, 61 deletions

diff --git a/drivers/net/vxlan.c b/drivers/net/vxlan.c
index e68c8eb4ea8e..4e2caaf8b5da 100644
--- a/drivers/net/vxlan.c
+++ b/drivers/net/vxlan.c
@@ -135,7 +135,7 @@ struct vxlan_dev {
 	__u16		  port_max;
 	__u8		  tos;		/* TOS override */
 	__u8		  ttl;
-	u32		  flags;	/* VXLAN_F_* below */
+	u32		  flags;	/* VXLAN_F_* in vxlan.h */
 
 	struct work_struct sock_work;
 	struct work_struct igmp_join;
@@ -150,13 +150,6 @@ struct vxlan_dev {
 	struct hlist_head fdb_head[FDB_HASH_SIZE];
 };
 
-#define VXLAN_F_LEARN	0x01
-#define VXLAN_F_PROXY	0x02
-#define VXLAN_F_RSC	0x04
-#define VXLAN_F_L2MISS	0x08
-#define VXLAN_F_L3MISS	0x10
-#define VXLAN_F_IPV6	0x20 /* internal flag */
-
 /* salt for hash table */
 static u32 vxlan_salt __read_mostly;
 static struct workqueue_struct *vxlan_wq;
@@ -1601,18 +1594,11 @@ __be16 vxlan_src_port(__u16 port_min, __u16 port_max, struct sk_buff *skb)
 }
 EXPORT_SYMBOL_GPL(vxlan_src_port);
 
-static int handle_offloads(struct sk_buff *skb)
+static inline struct sk_buff *vxlan_handle_offloads(struct sk_buff *skb,
+						    bool udp_csum)
 {
-	if (skb_is_gso(skb)) {
-		int err = skb_unclone(skb, GFP_ATOMIC);
-		if (unlikely(err))
-			return err;
-
-		skb_shinfo(skb)->gso_type |= SKB_GSO_UDP_TUNNEL;
-	} else if (skb->ip_summed != CHECKSUM_PARTIAL)
-		skb->ip_summed = CHECKSUM_NONE;
-
-	return 0;
+	int type = udp_csum ? SKB_GSO_UDP_TUNNEL_CSUM : SKB_GSO_UDP_TUNNEL;
+	return iptunnel_handle_offloads(skb, udp_csum, type);
 }
 
 #if IS_ENABLED(CONFIG_IPV6)
@@ -1629,10 +1615,9 @@ static int vxlan6_xmit_skb(struct vxlan_sock *vs,
 	int min_headroom;
 	int err;
 
-	if (!skb->encapsulation) {
-		skb_reset_inner_headers(skb);
-		skb->encapsulation = 1;
-	}
+	skb = vxlan_handle_offloads(skb, !udp_get_no_check6_tx(vs->sock->sk));
+	if (IS_ERR(skb))
+		return -EINVAL;
 
 	skb_scrub_packet(skb, xnet);
 
@@ -1666,27 +1651,14 @@ static int vxlan6_xmit_skb(struct vxlan_sock *vs,
 	uh->source = src_port;
 
 	uh->len = htons(skb->len);
-	uh->check = 0;
 
 	memset(&(IPCB(skb)->opt), 0, sizeof(IPCB(skb)->opt));
 	IPCB(skb)->flags &= ~(IPSKB_XFRM_TUNNEL_SIZE | IPSKB_XFRM_TRANSFORMED |
 			      IPSKB_REROUTED);
 	skb_dst_set(skb, dst);
 
-	if (!skb_is_gso(skb) && !(dst->dev->features & NETIF_F_IPV6_CSUM)) {
-		__wsum csum = skb_checksum(skb, 0, skb->len, 0);
-		skb->ip_summed = CHECKSUM_UNNECESSARY;
-		uh->check = csum_ipv6_magic(saddr, daddr, skb->len,
-					    IPPROTO_UDP, csum);
-		if (uh->check == 0)
-			uh->check = CSUM_MANGLED_0;
-	} else {
-		skb->ip_summed = CHECKSUM_PARTIAL;
-		skb->csum_start = skb_transport_header(skb) - skb->head;
-		skb->csum_offset = offsetof(struct udphdr, check);
-		uh->check = ~csum_ipv6_magic(saddr, daddr,
-					     skb->len, IPPROTO_UDP, 0);
-	}
+	udp6_set_csum(udp_get_no_check6_tx(vs->sock->sk), skb,
+		      saddr, daddr, skb->len);
 
 	__skb_push(skb, sizeof(*ip6h));
 	skb_reset_network_header(skb);
@@ -1702,10 +1674,6 @@ static int vxlan6_xmit_skb(struct vxlan_sock *vs,
 	ip6h->daddr	  = *daddr;
 	ip6h->saddr	  = *saddr;
 
-	err = handle_offloads(skb);
-	if (err)
-		return err;
-
 	ip6tunnel_xmit(skb, dev);
 	return 0;
 }
@@ -1721,10 +1689,9 @@ int vxlan_xmit_skb(struct vxlan_sock *vs,
 	int min_headroom;
 	int err;
 
-	if (!skb->encapsulation) {
-		skb_reset_inner_headers(skb);
-		skb->encapsulation = 1;
-	}
+	skb = vxlan_handle_offloads(skb, !vs->sock->sk->sk_no_check_tx);
+	if (IS_ERR(skb))
+		return -EINVAL;
 
 	min_headroom = LL_RESERVED_SPACE(rt->dst.dev) + rt->dst.header_len
 			+ VXLAN_HLEN + sizeof(struct iphdr)
@@ -1756,11 +1723,9 @@ int vxlan_xmit_skb(struct vxlan_sock *vs,
 	uh->source = src_port;
 
 	uh->len = htons(skb->len);
-	uh->check = 0;
 
-	err = handle_offloads(skb);
-	if (err)
-		return err;
+	udp_set_csum(vs->sock->sk->sk_no_check_tx, skb,
+		     src, dst, skb->len);
 
 	return iptunnel_xmit(vs->sock->sk, rt, skb, src, dst, IPPROTO_UDP,
 			     tos, ttl, df, xnet);
@@ -2405,7 +2370,7 @@ static void vxlan_del_work(struct work_struct *work)
  * could be used for both IPv4 and IPv6 communications, but
  * users may set bindv6only=1.
  */
-static struct socket *create_v6_sock(struct net *net, __be16 port)
+static struct socket *create_v6_sock(struct net *net, __be16 port, u32 flags)
 {
 	struct sock *sk;
 	struct socket *sock;
@@ -2442,18 +2407,25 @@ static struct socket *create_v6_sock(struct net *net, __be16 port)
 
 	/* Disable multicast loopback */
 	inet_sk(sk)->mc_loop = 0;
+
+	if (flags & VXLAN_F_UDP_ZERO_CSUM6_TX)
+		udp_set_no_check6_tx(sk, true);
+
+	if (flags & VXLAN_F_UDP_ZERO_CSUM6_RX)
+		udp_set_no_check6_rx(sk, true);
+
 	return sock;
 }
 
 #else
 
-static struct socket *create_v6_sock(struct net *net, __be16 port)
+static struct socket *create_v6_sock(struct net *net, __be16 port, u32 flags)
 {
 		return ERR_PTR(-EPFNOSUPPORT);
 }
 #endif
 
-static struct socket *create_v4_sock(struct net *net, __be16 port)
+static struct socket *create_v4_sock(struct net *net, __be16 port, u32 flags)
 {
 	struct sock *sk;
 	struct socket *sock;
@@ -2486,18 +2458,24 @@ static struct socket *create_v4_sock(struct net *net, __be16 port)
 
 	/* Disable multicast loopback */
 	inet_sk(sk)->mc_loop = 0;
+
+	if (!(flags & VXLAN_F_UDP_CSUM))
+		sock->sk->sk_no_check_tx = 1;
+
 	return sock;
 }
 
 /* Create new listen socket if needed */
 static struct vxlan_sock *vxlan_socket_create(struct net *net, __be16 port,
-					      vxlan_rcv_t *rcv, void *data, bool ipv6)
+					      vxlan_rcv_t *rcv, void *data,
+					      u32 flags)
 {
 	struct vxlan_net *vn = net_generic(net, vxlan_net_id);
 	struct vxlan_sock *vs;
 	struct socket *sock;
 	struct sock *sk;
 	unsigned int h;
+	bool ipv6 = !!(flags & VXLAN_F_IPV6);
 
 	vs = kzalloc(sizeof(*vs), GFP_KERNEL);
 	if (!vs)
@@ -2509,9 +2487,9 @@ static struct vxlan_sock *vxlan_socket_create(struct net *net, __be16 port,
 	INIT_WORK(&vs->del_work, vxlan_del_work);
 
 	if (ipv6)
-		sock = create_v6_sock(net, port);
+		sock = create_v6_sock(net, port, flags);
 	else
-		sock = create_v4_sock(net, port);
+		sock = create_v4_sock(net, port, flags);
 	if (IS_ERR(sock)) {
 		kfree(vs);
 		return ERR_CAST(sock);
@@ -2549,12 +2527,12 @@ static struct vxlan_sock *vxlan_socket_create(struct net *net, __be16 port,
 
 struct vxlan_sock *vxlan_sock_add(struct net *net, __be16 port,
 				  vxlan_rcv_t *rcv, void *data,
-				  bool no_share, bool ipv6)
+				  bool no_share, u32 flags)
 {
 	struct vxlan_net *vn = net_generic(net, vxlan_net_id);
 	struct vxlan_sock *vs;
 
-	vs = vxlan_socket_create(net, port, rcv, data, ipv6);
+	vs = vxlan_socket_create(net, port, rcv, data, flags);
 	if (!IS_ERR(vs))
 		return vs;
 
@@ -2587,7 +2565,7 @@ static void vxlan_sock_work(struct work_struct *work)
 	__be16 port = vxlan->dst_port;
 	struct vxlan_sock *nvs;
 
-	nvs = vxlan_sock_add(net, port, vxlan_rcv, NULL, false, vxlan->flags & VXLAN_F_IPV6);
+	nvs = vxlan_sock_add(net, port, vxlan_rcv, NULL, false, vxlan->flags);
 	spin_lock(&vn->sock_lock);
 	if (!IS_ERR(nvs))
 		vxlan_vs_add_dev(nvs, vxlan);
@@ -2711,6 +2689,17 @@ static int vxlan_newlink(struct net *net, struct net_device *dev,
 	if (data[IFLA_VXLAN_PORT])
 		vxlan->dst_port = nla_get_be16(data[IFLA_VXLAN_PORT]);
 
+	if (data[IFLA_VXLAN_UDP_CSUM] && nla_get_u8(data[IFLA_VXLAN_UDP_CSUM]))
+		vxlan->flags |= VXLAN_F_UDP_CSUM;
+
+	if (data[IFLA_VXLAN_UDP_ZERO_CSUM6_TX] &&
+	    nla_get_u8(data[IFLA_VXLAN_UDP_ZERO_CSUM6_TX]))
+		vxlan->flags |= VXLAN_F_UDP_ZERO_CSUM6_TX;
+
+	if (data[IFLA_VXLAN_UDP_ZERO_CSUM6_RX] &&
+	    nla_get_u8(data[IFLA_VXLAN_UDP_ZERO_CSUM6_RX]))
+		vxlan->flags |= VXLAN_F_UDP_ZERO_CSUM6_RX;
+
 	if (vxlan_find_vni(net, vni, vxlan->dst_port)) {
 		pr_info("duplicate VNI %u\n", vni);
 		return -EEXIST;
@@ -2774,7 +2763,10 @@ static size_t vxlan_get_size(const struct net_device *dev)
 		nla_total_size(sizeof(__u32)) +	/* IFLA_VXLAN_AGEING */
 		nla_total_size(sizeof(__u32)) +	/* IFLA_VXLAN_LIMIT */
 		nla_total_size(sizeof(struct ifla_vxlan_port_range)) +
-		nla_total_size(sizeof(__be16))+ /* IFLA_VXLAN_PORT */
+		nla_total_size(sizeof(__be16)) + /* IFLA_VXLAN_PORT */
+		nla_total_size(sizeof(__u8)) + /* IFLA_VXLAN_UDP_CSUM */
+		nla_total_size(sizeof(__u8)) + /* IFLA_VXLAN_UDP_ZERO_CSUM6_TX */
+		nla_total_size(sizeof(__u8)) + /* IFLA_VXLAN_UDP_ZERO_CSUM6_RX */
 		0;
 }
 
@@ -2834,7 +2826,13 @@ static int vxlan_fill_info(struct sk_buff *skb, const struct net_device *dev)
 			!!(vxlan->flags & VXLAN_F_L3MISS)) ||
 	    nla_put_u32(skb, IFLA_VXLAN_AGEING, vxlan->age_interval) ||
 	    nla_put_u32(skb, IFLA_VXLAN_LIMIT, vxlan->addrmax) ||
-	    nla_put_be16(skb, IFLA_VXLAN_PORT, vxlan->dst_port))
+	    nla_put_be16(skb, IFLA_VXLAN_PORT, vxlan->dst_port) ||
+	    nla_put_u8(skb, IFLA_VXLAN_UDP_CSUM,
+			!!(vxlan->flags & VXLAN_F_UDP_CSUM)) ||
+	    nla_put_u8(skb, IFLA_VXLAN_UDP_ZERO_CSUM6_TX,
+			!!(vxlan->flags & VXLAN_F_UDP_ZERO_CSUM6_TX)) ||
+	    nla_put_u8(skb, IFLA_VXLAN_UDP_ZERO_CSUM6_RX,
+			!!(vxlan->flags & VXLAN_F_UDP_ZERO_CSUM6_RX)))
 		goto nla_put_failure;
 
 	if (nla_put(skb, IFLA_VXLAN_PORT_RANGE, sizeof(ports), &ports))