[ovs-dev] [PATCH net-next v3 2/2] datapath: Restructure vxlan tunneling.

Kyle Mestery (kmestery) kmestery at cisco.com
Fri Jul 19 13:28:42 UTC 2013


On Jul 18, 2013, at 5:22 PM, Pravin B Shelar <pshelar at nicira.com> wrote:

> Following patch restructures vxlan tunneling so that it is more
> in sync with upstream vxlan tunneling code.
> 
> Signed-off-by: Pravin Shelar <pshelar at nicira.com>
> ---
> v3-v2:
> - Moved kernel version in flow_dissector check to top.
> v1-v2:
> - Added create flag to vxlan-port add.
> - Moved rxhash functions to flow_dissector.c
> ---
> datapath/compat.h                             |    6 +
> datapath/linux/Modules.mk                     |    6 +-
> datapath/linux/compat/flow_dissector.c        |  203 +++++++++++
> datapath/linux/compat/include/linux/in.h      |   20 ++
> datapath/linux/compat/include/linux/skbuff.h  |   22 ++
> datapath/linux/compat/include/net/flow_keys.h |   22 ++
> datapath/linux/compat/include/net/ip.h        |    7 +
> datapath/linux/compat/include/net/ipv6.h      |   15 +
> datapath/linux/compat/include/net/vxlan.h     |   43 +++
> datapath/linux/compat/vxlan.c                 |  457 +++++++++++++++++++++++++
> datapath/vport-vxlan.c                        |  221 +++++--------
> 11 files changed, 877 insertions(+), 145 deletions(-)
> create mode 100644 datapath/linux/compat/flow_dissector.c
> create mode 100644 datapath/linux/compat/include/net/flow_keys.h
> create mode 100644 datapath/linux/compat/include/net/vxlan.h
> create mode 100644 datapath/linux/compat/vxlan.c
> 
> diff --git a/datapath/compat.h b/datapath/compat.h
> index a6a01d5..4dfd192 100644
> --- a/datapath/compat.h
> +++ b/datapath/compat.h
> @@ -100,4 +100,10 @@ static inline void skb_set_mark(struct sk_buff *skb, u32 mark)
> #define rt_dst(rt) (rt->u.dst)
> #endif
> 
> +#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,33)
> +#define inet_sport(sk)	(inet_sk(sk)->sport)
> +#else
> +#define inet_sport(sk)	(inet_sk(sk)->inet_sport)
> +#endif
> +
> #endif /* compat.h */
> diff --git a/datapath/linux/Modules.mk b/datapath/linux/Modules.mk
> index dcacc79..edaeabb 100644
> --- a/datapath/linux/Modules.mk
> +++ b/datapath/linux/Modules.mk
> @@ -3,6 +3,7 @@ openvswitch_sources += \
> 	linux/compat/dev-openvswitch.c \
> 	linux/compat/exthdrs_core.c \
> 	linux/compat/flex_array.c \
> +	linux/compat/flow_dissector.c \
> 	linux/compat/gre.c \
> 	linux/compat/gso.c \
> 	linux/compat/genetlink-openvswitch.c \
> @@ -14,6 +15,7 @@ openvswitch_sources += \
> 	linux/compat/reciprocal_div.c \
> 	linux/compat/skbuff-openvswitch.c \
> 	linux/compat/time.c	\
> +	linux/compat/vxlan.c	\
> 	linux/compat/workqueue.c
> openvswitch_headers += \
> 	linux/compat/gso.h \
> @@ -65,6 +67,7 @@ openvswitch_headers += \
> 	linux/compat/include/linux/workqueue.h \
> 	linux/compat/include/net/checksum.h \
> 	linux/compat/include/net/dst.h \
> +	linux/compat/include/net/flow_keys.h \
> 	linux/compat/include/net/genetlink.h \
> 	linux/compat/include/net/gre.h \
> 	linux/compat/include/net/inet_frag.h \
> @@ -76,4 +79,5 @@ openvswitch_headers += \
> 	linux/compat/include/net/protocol.h \
> 	linux/compat/include/net/route.h \
> 	linux/compat/include/net/sock.h \
> -	linux/compat/include/net/netns/generic.h
> +	linux/compat/include/net/netns/generic.h \
> +	linux/compat/include/net/vxlan.h
> diff --git a/datapath/linux/compat/flow_dissector.c b/datapath/linux/compat/flow_dissector.c
> new file mode 100644
> index 0000000..c2078d6
> --- /dev/null
> +++ b/datapath/linux/compat/flow_dissector.c
> @@ -0,0 +1,203 @@
> +
> +#include <linux/version.h>
> +#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,37)
> +#include <linux/ip.h>
> +#include <linux/ipv6.h>
> +#include <linux/if_vlan.h>
> +#include <net/ip.h>
> +#include <net/ipv6.h>
> +#include <linux/igmp.h>
> +#include <linux/icmp.h>
> +#include <linux/sctp.h>
> +#include <linux/dccp.h>
> +#include <linux/if_tunnel.h>
> +#include <linux/if_pppox.h>
> +#include <linux/ppp_defs.h>
> +#include <net/flow_keys.h>
> +
This file appears to be missing license and copyright information.

> +
> +/* copy saddr & daddr, possibly using 64bit load/store
> + * Equivalent to :	flow->src = iph->saddr;
> + *			flow->dst = iph->daddr;
> + */
> +static void iph_to_flow_copy_addrs(struct flow_keys *flow, const struct iphdr *iph)
> +{
> +	BUILD_BUG_ON(offsetof(typeof(*flow), dst) !=
> +		     offsetof(typeof(*flow), src) + sizeof(flow->src));
> +	memcpy(&flow->src, &iph->saddr, sizeof(flow->src) + sizeof(flow->dst));
> +}
> +
> +static bool skb_flow_dissect(const struct sk_buff *skb, struct flow_keys *flow)
> +{
> +	int poff, nhoff = skb_network_offset(skb);
> +	u8 ip_proto;
> +	__be16 proto = skb->protocol;
> +
> +	memset(flow, 0, sizeof(*flow));
> +
> +again:
> +	switch (proto) {
> +	case __constant_htons(ETH_P_IP): {
> +		const struct iphdr *iph;
> +		struct iphdr _iph;
> +ip:
> +		iph = skb_header_pointer(skb, nhoff, sizeof(_iph), &_iph);
> +		if (!iph)
> +			return false;
> +
> +		if (ip_is_fragment(iph))
> +			ip_proto = 0;
> +		else
> +			ip_proto = iph->protocol;
> +		iph_to_flow_copy_addrs(flow, iph);
> +		nhoff += iph->ihl * 4;
> +		break;
> +	}
> +	case __constant_htons(ETH_P_IPV6): {
> +		const struct ipv6hdr *iph;
> +		struct ipv6hdr _iph;
> +ipv6:
> +		iph = skb_header_pointer(skb, nhoff, sizeof(_iph), &_iph);
> +		if (!iph)
> +			return false;
> +
> +		ip_proto = iph->nexthdr;
> +		flow->src = (__force __be32)ipv6_addr_hash(&iph->saddr);
> +		flow->dst = (__force __be32)ipv6_addr_hash(&iph->daddr);
> +		nhoff += sizeof(struct ipv6hdr);
> +		break;
> +	}
> +	case __constant_htons(ETH_P_8021Q): {
> +		const struct vlan_hdr *vlan;
> +		struct vlan_hdr _vlan;
> +
> +		vlan = skb_header_pointer(skb, nhoff, sizeof(_vlan), &_vlan);
> +		if (!vlan)
> +			return false;
> +
> +		proto = vlan->h_vlan_encapsulated_proto;
> +		nhoff += sizeof(*vlan);
> +		goto again;
> +	}
> +	case __constant_htons(ETH_P_PPP_SES): {
> +		struct {
> +			struct pppoe_hdr hdr;
> +			__be16 proto;
> +		} *hdr, _hdr;
> +		hdr = skb_header_pointer(skb, nhoff, sizeof(_hdr), &_hdr);
> +		if (!hdr)
> +			return false;
> +		proto = hdr->proto;
> +		nhoff += PPPOE_SES_HLEN;
> +		switch (proto) {
> +		case __constant_htons(PPP_IP):
> +			goto ip;
> +		case __constant_htons(PPP_IPV6):
> +			goto ipv6;
> +		default:
> +			return false;
> +		}
> +	}
> +	default:
> +		return false;
> +	}
> +
> +	switch (ip_proto) {
> +	case IPPROTO_GRE: {
> +		struct gre_hdr {
> +			__be16 flags;
> +			__be16 proto;
> +		} *hdr, _hdr;
> +
> +		hdr = skb_header_pointer(skb, nhoff, sizeof(_hdr), &_hdr);
> +		if (!hdr)
> +			return false;
> +		/*
> +		 * Only look inside GRE if version zero and no
> +		 * routing
> +		 */
> +		if (!(hdr->flags & (GRE_VERSION|GRE_ROUTING))) {
> +			proto = hdr->proto;
> +			nhoff += 4;
> +			if (hdr->flags & GRE_CSUM)
> +				nhoff += 4;
> +			if (hdr->flags & GRE_KEY)
> +				nhoff += 4;
> +			if (hdr->flags & GRE_SEQ)
> +				nhoff += 4;
> +			if (proto == htons(ETH_P_TEB)) {
> +				const struct ethhdr *eth;
> +				struct ethhdr _eth;
> +
> +				eth = skb_header_pointer(skb, nhoff,
> +							 sizeof(_eth), &_eth);
> +				if (!eth)
> +					return false;
> +				proto = eth->h_proto;
> +				nhoff += sizeof(*eth);
> +			}
> +			goto again;
> +		}
> +		break;
> +	}
> +	case IPPROTO_IPIP:
> +		goto again;
> +	default:
> +		break;
> +	}
> +
> +	flow->ip_proto = ip_proto;
> +	poff = proto_ports_offset(ip_proto);
> +	if (poff >= 0) {
> +		__be32 *ports, _ports;
> +
> +		nhoff += poff;
> +		ports = skb_header_pointer(skb, nhoff, sizeof(_ports), &_ports);
> +		if (ports)
> +			flow->ports = *ports;
> +	}
> +
> +	flow->thoff = (u16) nhoff;
> +
> +	return true;
> +}
> +
> +static u32 hashrnd __read_mostly;
> +
> +static void init_hashrnd(void)
> +{
> +	if (likely(hashrnd))
> +		return;
> +	get_random_bytes(&hashrnd, sizeof(hashrnd));
> +}
> +
> +u32 __skb_get_rxhash(struct sk_buff *skb)
> +{
> +	struct flow_keys keys;
> +	u32 hash;
> +
> +	if (!skb_flow_dissect(skb, &keys))
> +		return 0;
> +
> +	/* get a consistent hash (same value on both flow directions) */
> +	if (((__force u32)keys.dst < (__force u32)keys.src) ||
> +	    (((__force u32)keys.dst == (__force u32)keys.src) &&
> +	     ((__force u16)keys.port16[1] < (__force u16)keys.port16[0]))) {
> +		swap(keys.dst, keys.src);
> +		swap(keys.port16[0], keys.port16[1]);
> +	}
> +
> +	init_hashrnd();
> +
> +	hash = jhash_3words((__force u32)keys.dst,
> +			    (__force u32)keys.src,
> +			    (__force u32)keys.ports, hashrnd);
> +	if (!hash)
> +		hash = 1;
> +
> +#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,34)
> +	skb->rxhash = hash;
> +#endif
> +	return hash;
> +}
> +#endif
> diff --git a/datapath/linux/compat/include/linux/in.h b/datapath/linux/compat/include/linux/in.h
> index f91a832..fa2e026 100644
> --- a/datapath/linux/compat/include/linux/in.h
> +++ b/datapath/linux/compat/include/linux/in.h
> @@ -3,6 +3,26 @@
> 
> #include_next <linux/in.h>
> 
> +#include <linux/module.h>
> +#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,37)
> +static inline int proto_ports_offset(int proto)
> +{
> +	switch (proto) {
> +	case IPPROTO_TCP:
> +	case IPPROTO_UDP:
> +	case IPPROTO_DCCP:
> +	case IPPROTO_ESP:	/* SPI */
> +	case IPPROTO_SCTP:
> +	case IPPROTO_UDPLITE:
> +		return 0;
> +	case IPPROTO_AH:	/* SPI */
> +		return 4;
> +	default:
> +		return -EINVAL;
> +	}
> +}
> +#endif
> +
> #ifndef HAVE_IPV4_IS_MULTICAST
> 
> static inline bool ipv4_is_loopback(__be32 addr)
> diff --git a/datapath/linux/compat/include/linux/skbuff.h b/datapath/linux/compat/include/linux/skbuff.h
> index d485b39..c9c103d 100644
> --- a/datapath/linux/compat/include/linux/skbuff.h
> +++ b/datapath/linux/compat/include/linux/skbuff.h
> @@ -251,4 +251,26 @@ static inline void skb_reset_mac_len(struct sk_buff *skb)
> 	skb->mac_len = skb->network_header - skb->mac_header;
> }
> #endif
> +
> +static inline int skb_unclone(struct sk_buff *skb, gfp_t pri)
> +{
> +	might_sleep_if(pri & __GFP_WAIT);
> +
> +	if (skb_cloned(skb))
> +		return pskb_expand_head(skb, 0, 0, pri);
> +
> +	return 0;
> +}
> +
> +#if LINUX_VERSION_CODE < KERNEL_VERSION(2,6,37)
> +extern u32 __skb_get_rxhash(struct sk_buff *skb);
> +static inline __u32 skb_get_rxhash(struct sk_buff *skb)
> +{
> +#if LINUX_VERSION_CODE > KERNEL_VERSION(2,6,34)
> +	if (!skb->rxhash)
> +#endif
> +	return __skb_get_rxhash(skb);
> +}
> +#endif
> +
> #endif
> diff --git a/datapath/linux/compat/include/net/flow_keys.h b/datapath/linux/compat/include/net/flow_keys.h
> new file mode 100644
> index 0000000..4de17d1
> --- /dev/null
> +++ b/datapath/linux/compat/include/net/flow_keys.h
> @@ -0,0 +1,22 @@
> +#ifndef _NET_FLOW_KEYS_WRAPPER_H
> +#define _NET_FLOW_KEYS_WRAPPER_H
> +
> +#include <linux/version.h>
> +
> +#if LINUX_VERSION_CODE >= KERNEL_VERSION(3,3,0)
> +#include_next <net/flow_keys.h>
> +#else
> +struct flow_keys {
> +	/* (src,dst) must be grouped, in the same way than in IP header */
> +	__be32 src;
> +	__be32 dst;
> +	union {
> +		__be32 ports;
> +		__be16 port16[2];
> +	};
> +	u16 thoff;
> +	u8 ip_proto;
> +};
> +#endif
> +
> +#endif
> diff --git a/datapath/linux/compat/include/net/ip.h b/datapath/linux/compat/include/net/ip.h
> index b18b968..1dccdea 100644
> --- a/datapath/linux/compat/include/net/ip.h
> +++ b/datapath/linux/compat/include/net/ip.h
> @@ -11,4 +11,11 @@ extern int		ip_local_out(struct sk_buff *skb);
> 
> #endif /* linux kernel < 2.6.25 */
> 
> +#if LINUX_VERSION_CODE < KERNEL_VERSION(3,1,0)
> +static inline bool ip_is_fragment(const struct iphdr *iph)
> +{
> +	return (iph->frag_off & htons(IP_MF | IP_OFFSET)) != 0;
> +}
> +#endif
> +
> #endif
> diff --git a/datapath/linux/compat/include/net/ipv6.h b/datapath/linux/compat/include/net/ipv6.h
> index d1e3248..7ab234a 100644
> --- a/datapath/linux/compat/include/net/ipv6.h
> +++ b/datapath/linux/compat/include/net/ipv6.h
> @@ -23,4 +23,19 @@ enum {
> extern int ipv6_find_hdr(const struct sk_buff *skb, unsigned int *offset,
> 			 int target, unsigned short *fragoff, int *fragflg);
> 
> +#if LINUX_VERSION_CODE < KERNEL_VERSION(3,4,0)
> +static inline u32 ipv6_addr_hash(const struct in6_addr *a)
> +{
> +#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && BITS_PER_LONG == 64
> +	const unsigned long *ul = (const unsigned long *)a;
> +	unsigned long x = ul[0] ^ ul[1];
> +
> +	return (u32)(x ^ (x >> 32));
> +#else
> +	return (__force u32)(a->s6_addr32[0] ^ a->s6_addr32[1] ^
> +			     a->s6_addr32[2] ^ a->s6_addr32[3]);
> +#endif
> +}
> +#endif
> +
> #endif
> diff --git a/datapath/linux/compat/include/net/vxlan.h b/datapath/linux/compat/include/net/vxlan.h
> new file mode 100644
> index 0000000..102bc0c
> --- /dev/null
> +++ b/datapath/linux/compat/include/net/vxlan.h
> @@ -0,0 +1,43 @@
> +#ifndef __NET_VXLAN_WRAPPER_H
> +#define __NET_VXLAN_WRAPPER_H  1
> +
> +#include <linux/skbuff.h>
> +#include <linux/netdevice.h>
> +#include <linux/udp.h>
> +
> +/* per UDP socket information */
> +struct vxlan_sock {
> +	struct hlist_node hlist;
> +	struct rcu_head	  rcu;
> +	struct socket	  *sock;
> +	struct list_head  handler_list;
> +};
> +
> +struct vxlan_handler;
> +typedef int (vxlan_rcv_t)(struct vxlan_handler *vh, struct sk_buff *skb, __be32 key);
> +
> +struct vxlan_handler {
> +	vxlan_rcv_t	  *rcv;
> +	struct list_head   node;
> +	void		  *data;
> +	struct vxlan_sock *vs;
> +	atomic_t	   refcnt;
> +	struct rcu_head    rcu;
> +	struct work_struct del_work;
> +	int		   priority;
> +};
> +
> +void vxlan_handler_put(struct vxlan_handler *vh);
> +
> +struct vxlan_handler *vxlan_handler_add(struct net *net,
> +					__be16 portno, vxlan_rcv_t *rcv,
> +					void *data, int priority, bool create);
> +
> +int vxlan_xmit_skb(struct net *net, struct vxlan_handler *vh,
> +		   struct rtable *rt, struct sk_buff *skb,
> +		   __be32 src, __be32 dst, __u8 tos, __u8 ttl, __be16 df,
> +		   __be16 src_port, __be16 dst_port, __be32 vni);
> +
> +__be16 vxlan_src_port(__u16 port_min, __u16 port_max, struct sk_buff *skb);
> +
> +#endif
> diff --git a/datapath/linux/compat/vxlan.c b/datapath/linux/compat/vxlan.c
> new file mode 100644
> index 0000000..b41ecc2
> --- /dev/null
> +++ b/datapath/linux/compat/vxlan.c
> @@ -0,0 +1,457 @@
> +#include <linux/kernel.h>
> +#include <linux/types.h>
> +#include <linux/module.h>
> +#include <linux/errno.h>
> +#include <linux/slab.h>
> +#include <linux/skbuff.h>
> +#include <linux/rculist.h>
> +#include <linux/netdevice.h>
> +#include <linux/in.h>
> +#include <linux/ip.h>
> +#include <linux/udp.h>
> +#include <linux/igmp.h>
> +#include <linux/etherdevice.h>
> +#include <linux/if_ether.h>
> +#include <linux/if_vlan.h>
> +#include <linux/hash.h>
> +#include <linux/ethtool.h>
> +#include <net/arp.h>
> +#include <net/ndisc.h>
> +#include <net/ip.h>
> +#include <net/ip_tunnels.h>
> +#include <net/icmp.h>
> +#include <net/udp.h>
> +#include <net/rtnetlink.h>
> +#include <net/route.h>
> +#include <net/dsfield.h>
> +#include <net/inet_ecn.h>
> +#include <net/net_namespace.h>
> +#include <net/netns/generic.h>
> +#include <net/vxlan.h>
> +
Same thing here, no license or copyright.

> +#include "checksum.h"
> +#include "compat.h"
> +#include "gso.h"
> +#include "vlan.h"
> +
> +#define PORT_HASH_BITS	8
> +#define PORT_HASH_SIZE  (1<<PORT_HASH_BITS)
> +
> +#define VXLAN_N_VID	(1u << 24)
> +#define VXLAN_VID_MASK	(VXLAN_N_VID - 1)
> +/* IP header + UDP + VXLAN + Ethernet header */
> +#define VXLAN_HEADROOM (20 + 8 + 8 + 14)
> +#define VXLAN_HLEN (sizeof(struct udphdr) + sizeof(struct vxlanhdr))
> +
> +#define VXLAN_FLAGS 0x08000000	/* struct vxlanhdr.vx_flags required value. */
> +
> +/* VXLAN protocol header */
> +struct vxlanhdr {
> +	__be32 vx_flags;
> +	__be32 vx_vni;
> +};
> +
> +static int vxlan_net_id;
> +
> +/* per-network namespace private data for this module */
> +struct vxlan_net {
> +	struct hlist_head sock_list[PORT_HASH_SIZE];
> +	struct mutex	  sock_lock;	/* RTNL lock nests inside this lock. */
> +};
> +
> +/* Socket hash table head */
> +static inline struct hlist_head *vs_head(struct net *net, __be16 port)
> +{
> +	struct vxlan_net *vn = net_generic(net, vxlan_net_id);
> +
> +	return &vn->sock_list[hash_32(ntohs(port), PORT_HASH_BITS)];
> +}
> +
> +/* Find VXLAN socket based on network namespace and UDP port */
> +static struct vxlan_sock *vxlan_find_port(struct net *net, __be16 port)
> +{
> +	struct vxlan_sock *vs;
> +
> +	hlist_for_each_entry_rcu(vs, vs_head(net, port), hlist) {
> +		if (inet_sport(vs->sock->sk) == port)
> +			return vs;
> +	}
> +	return NULL;
> +}
> +
> +/* Callback from net/ipv4/udp.c to receive packets */
> +static int vxlan_udp_encap_recv(struct sock *sk, struct sk_buff *skb)
> +{
> +	struct vxlan_handler *vh;
> +	struct vxlan_sock *vs;
> +	struct vxlanhdr *vxh;
> +
> +	/* Need Vxlan and inner Ethernet header to be present */
> +	if (!pskb_may_pull(skb, VXLAN_HLEN))
> +		goto error;
> +
> +	/* Return packets with reserved bits set */
> +	vxh = (struct vxlanhdr *)(udp_hdr(skb) + 1);
> +	if (vxh->vx_flags != htonl(VXLAN_FLAGS) ||
> +	    (vxh->vx_vni & htonl(0xff))) {
> +		printk("invalid vxlan flags=%#x vni=%#x\n",
> +			ntohl(vxh->vx_flags), ntohl(vxh->vx_vni));
> +		goto error;
> +	}
> +
> +	if (iptunnel_pull_header(skb, VXLAN_HLEN, htons(ETH_P_TEB)))
> +		goto drop;
> +
> +	vs = vxlan_find_port(sock_net(sk), inet_sport(sk));
> +	if (!vs)
> +		goto drop;
> +
> +	list_for_each_entry_rcu(vh, &vs->handler_list, node) {
> +		if (vh->rcv(vh, skb, vxh->vx_vni) == PACKET_RCVD)
> +			return 0;
> +	}
> +
> +drop:
> +	/* Consume bad packet */
> +	kfree_skb(skb);
> +	return 0;
> +
> +error:
> +	/* Return non vxlan pkt */
> +	return 1;
> +}
> +
> +static void vxlan_sock_put(struct sk_buff *skb)
> +{
> +	sock_put(skb->sk);
> +}
> +
> +/* On transmit, associate with the tunnel socket */
> +static void vxlan_set_owner(struct sock *sk, struct sk_buff *skb)
> +{
> +	skb_orphan(skb);
> +	sock_hold(sk);
> +	skb->sk = sk;
> +	skb->destructor = vxlan_sock_put;
> +}
> +
> +/* Compute source port for outgoing packet
> + *   first choice to use L4 flow hash since it will spread
> + *     better and maybe available from hardware
> + *   secondary choice is to use jhash on the Ethernet header
> + */
> +__be16 vxlan_src_port(__u16 port_min, __u16 port_max, struct sk_buff *skb)
> +{
> +	unsigned int range = (port_max - port_min) + 1;
> +	u32 hash;
> +
> +	hash = skb_get_rxhash(skb);
> +	if (!hash)
> +		hash = jhash(skb->data, 2 * ETH_ALEN,
> +			     (__force u32) skb->protocol);
> +
> +	return htons((((u64) hash * range) >> 32) + port_min);
> +}
> +
> +static void vxlan_gso(struct sk_buff *skb)
> +{
> +	int udp_offset = skb_transport_offset(skb);
> +	struct udphdr *uh;
> +
> +	uh = udp_hdr(skb);
> +	uh->len = htons(skb->len - udp_offset);
> +
> +	/* csum segment if tunnel sets skb with csum. */
> +	if (unlikely(uh->check)) {
> +		struct iphdr *iph = ip_hdr(skb);
> +
> +		uh->check = ~csum_tcpudp_magic(iph->saddr, iph->daddr,
> +					       skb->len - udp_offset,
> +					       IPPROTO_UDP, 0);
> +		uh->check = csum_fold(skb_checksum(skb, udp_offset,
> +				      skb->len - udp_offset, 0));
> +
> +		if (uh->check == 0)
> +			uh->check = CSUM_MANGLED_0;
> +
> +	}
> +	skb->ip_summed = CHECKSUM_NONE;
> +}
> +
> +static int handle_offloads(struct sk_buff *skb)
> +{
> +	if (skb_is_gso(skb)) {
> +		OVS_GSO_CB(skb)->fix_segment = vxlan_gso;
> +	} else {
> +		if (skb->ip_summed != CHECKSUM_PARTIAL)
> +			skb->ip_summed = CHECKSUM_NONE;
> +	}
> +	return 0;
> +}
> +
> +int vxlan_xmit_skb(struct net *net, struct vxlan_handler *vh,
> +		   struct rtable *rt, struct sk_buff *skb,
> +		   __be32 src, __be32 dst, __u8 tos, __u8 ttl, __be16 df,
> +		   __be16 src_port, __be16 dst_port, __be32 vni)
> +{
> +	struct vxlanhdr *vxh;
> +	struct udphdr *uh;
> +	int min_headroom;
> +	int err;
> +
> +	skb_reset_inner_headers(skb);
> +
> +	min_headroom = LL_RESERVED_SPACE(rt_dst(rt).dev) + rt_dst(rt).header_len
> +			+ VXLAN_HLEN + sizeof(struct iphdr)
> +			+ (vlan_tx_tag_present(skb) ? VLAN_HLEN : 0);
> +
> +	/* Need space for new headers (invalidates iph ptr) */
> +	err = skb_cow_head(skb, min_headroom);
> +	if (unlikely(err))
> +		return err;
> +
> +	if (unlikely(vlan_deaccel_tag(skb)))
> +		return -ENOMEM;
> +
> +	vxh = (struct vxlanhdr *) __skb_push(skb, sizeof(*vxh));
> +	vxh->vx_flags = htonl(VXLAN_FLAGS);
> +	vxh->vx_vni = vni;
> +
> +	__skb_push(skb, sizeof(*uh));
> +	skb_reset_transport_header(skb);
> +	uh = udp_hdr(skb);
> +
> +	uh->dest = dst_port;
> +	uh->source = src_port;
> +
> +	uh->len = htons(skb->len);
> +	uh->check = 0;
> +
> +	vxlan_set_owner(vh->vs->sock->sk, skb);
> +
> +	err = handle_offloads(skb);
> +	if (err)
> +		return err;
> +
> +	return iptunnel_xmit(net, rt, skb, src, dst,
> +			IPPROTO_UDP, tos, ttl, df);
> +}
> +
> +static struct vxlan_sock *vxlan_socket_create(struct net *net, __be16 port)
> +{
> +	struct vxlan_sock *vs;
> +	struct sock *sk;
> +	struct sockaddr_in vxlan_addr = {
> +		.sin_family = AF_INET,
> +		.sin_addr.s_addr = htonl(INADDR_ANY),
> +		.sin_port = port,
> +	};
> +	int rc;
> +
> +	vs = kmalloc(sizeof(*vs), GFP_KERNEL);
> +	if (!vs)
> +		return ERR_PTR(-ENOMEM);
> +
> +	/* Create UDP socket for encapsulation receive. */
> +	rc = sock_create_kern(AF_INET, SOCK_DGRAM, IPPROTO_UDP, &vs->sock);
> +	if (rc < 0) {
> +		pr_debug("UDP socket create failed\n");
> +		kfree(vs);
> +		return ERR_PTR(rc);
> +	}
> +
> +	/* Put in proper namespace */
> +	sk = vs->sock->sk;
> +	sk_change_net(sk, net);
> +
> +	rc = kernel_bind(vs->sock, (struct sockaddr *) &vxlan_addr,
> +			 sizeof(vxlan_addr));
> +	if (rc < 0) {
> +		pr_debug("bind for UDP socket %pI4:%u (%d)\n",
> +			 &vxlan_addr.sin_addr, ntohs(vxlan_addr.sin_port), rc);
> +		sk_release_kernel(sk);
> +		kfree(vs);
> +		return ERR_PTR(rc);
> +	}
> +
> +	/* Disable multicast loopback */
> +	inet_sk(sk)->mc_loop = 0;
> +	INIT_LIST_HEAD(&vs->handler_list);
> +	hlist_add_head_rcu(&vs->hlist, vs_head(net, port));
> +
> +	/* Mark socket as an encapsulation socket. */
> +	udp_sk(sk)->encap_type = 1;
> +	udp_sk(sk)->encap_rcv = vxlan_udp_encap_recv;
> +	udp_encap_enable();
> +
> +	return vs;
> +}
> +
> +static void rcu_free_vs_callback(struct rcu_head *rcu)
> +{
> +	struct vxlan_sock *vs = container_of(rcu, struct vxlan_sock, rcu);
> +
> +	kfree(vs);
> +}
> +
> +static void vxlan_socket_del(struct vxlan_sock *vs)
> +{
> +	if (list_empty(&vs->handler_list)) {
> +		hlist_del_rcu(&vs->hlist);
> +
> +		sk_release_kernel(vs->sock->sk);
> +		call_rcu(&vs->rcu, rcu_free_vs_callback);
> +	}
> +}
> +
> +static int vxlan_init_module(void);
> +static void vxlan_cleanup_module(void);
> +
> +static void rcu_free_vh_callback(struct rcu_head *rcu)
> +{
> +	struct vxlan_handler *vh = container_of(rcu, struct vxlan_handler, rcu);
> +
> +	kfree(vh);
> +}
> +
> +static void vh_del_work(struct work_struct *work)
> +{
> +	struct vxlan_handler *vh = container_of(work, struct vxlan_handler, del_work);
> +	struct vxlan_sock *vs = vh->vs;
> +	struct net *net = sock_net(vs->sock->sk);
> +	struct vxlan_net *vn = net_generic(net, vxlan_net_id);
> +
> +	mutex_lock(&vn->sock_lock);
> +
> +	list_del_rcu(&vh->node);
> +	call_rcu(&vh->rcu, rcu_free_vh_callback);
> +	vxlan_socket_del(vs);
> +
> +	mutex_unlock(&vn->sock_lock);
> +
> +	vxlan_cleanup_module();
> +}
> +
> +struct vxlan_handler *vxlan_handler_add(struct net *net,
> +					__be16 portno, vxlan_rcv_t *rcv,
> +					void *data, int priority, bool create)
> +{
> +	struct vxlan_net *vn;
> +	struct vxlan_sock *vs;
> +	struct vxlan_handler *vh;
> +	struct vxlan_handler *new;
> +	int err;
> +
> +	err = vxlan_init_module();
> +	if (err)
> +		return ERR_PTR(err);
> +
> +	vn = net_generic(net, vxlan_net_id);
> +	mutex_lock(&vn->sock_lock);
> +	/* Look to see if can reuse socket */
> +	vs = vxlan_find_port(net, portno);
> +	if (!vs) {
> +		vs = vxlan_socket_create(net, portno);
> +		if (IS_ERR(vs)) {
> +			new = (void *) vs;
> +			goto out;
> +		}
> +	}
> +
> +	/* Try existing vxlan hanlders for this socket. */
> +	list_for_each_entry(vh, &vs->handler_list, node) {
> +		if (vh->rcv == rcv) {
> +			if (create) {
> +				vxlan_socket_del(vs);
> +				new = ERR_PTR(-EEXIST);
> +				goto out;
> +			}
> +			atomic_inc(&vh->refcnt);
> +			new = vh;
> +			goto out;
> +		}
> +	}
> +
> +	new = kzalloc(sizeof(*new), GFP_KERNEL);
> +	if (!new) {
> +		vxlan_socket_del(vs);
> +		new = ERR_PTR(-ENOMEM);
> +		goto out;
> +	}
> +
> +	new->rcv = rcv;
> +	new->vs = vs;
> +	atomic_set(&new->refcnt, 1);
> +	INIT_WORK(&new->del_work, vh_del_work);
> +	new->data = data;
> +	new->priority = priority;
> +
> +	list_for_each_entry(vh, &vs->handler_list, node) {
> +		if (vh->priority > priority) {
> +			list_add_tail_rcu(&new->node, &vh->node);
> +			goto out;
> +		}
> +	}
> +
> +	list_add_tail_rcu(&new->node, &vs->handler_list);
> +out:
> +	mutex_unlock(&vn->sock_lock);
> +	return new;
> +}
> +
> +void vxlan_handler_put(struct vxlan_handler *vh)
> +{
> +	BUG_ON(!vh->vs);
> +
> +	if (atomic_dec_and_test(&vh->refcnt))
> +		queue_work(&vh->del_work);
> +}
> +
> +static __net_init int vxlan_init_net(struct net *net)
> +{
> +	struct vxlan_net *vn = net_generic(net, vxlan_net_id);
> +	unsigned int h;
> +
> +	mutex_init(&vn->sock_lock);
> +
> +	for (h = 0; h < PORT_HASH_SIZE; ++h)
> +		INIT_HLIST_HEAD(&vn->sock_list[h]);
> +
> +	return 0;
> +}
> +
> +static struct pernet_operations vxlan_net_ops = {
> +	.init = vxlan_init_net,
> +	.id   = &vxlan_net_id,
> +	.size = sizeof(struct vxlan_net),
> +};
> +
> +static int refcnt;
> +static DEFINE_MUTEX(init_lock);
> +DEFINE_COMPAT_PNET_REG_FUNC(gen_device);
> +
> +static int vxlan_init_module(void)
> +{
> +	int err = 0;
> +
> +	mutex_lock(&init_lock);
> +	if (refcnt)
> +		goto out;
> +	err = register_pernet_device(&vxlan_net_ops);
> +out:
> +	if (!err)
> +		refcnt++;
> +	mutex_unlock(&init_lock);
> +	return err;
> +}
> +
> +static void vxlan_cleanup_module(void)
> +{
> +	mutex_lock(&init_lock);
> +	refcnt--;
> +	if (refcnt)
> +		goto out;
> +	unregister_pernet_device(&vxlan_net_ops);
> +out:
> +	mutex_unlock(&init_lock);
> +}
> diff --git a/datapath/vport-vxlan.c b/datapath/vport-vxlan.c
> index 7ff51fd..5546820 100644
> --- a/datapath/vport-vxlan.c
> +++ b/datapath/vport-vxlan.c
> @@ -31,164 +31,60 @@
> #include <net/icmp.h>
> #include <net/ip.h>
> #include <net/udp.h>
> +#include <net/ip_tunnels.h>
> +#include <net/udp.h>
> +#include <net/rtnetlink.h>
> +#include <net/route.h>
> +#include <net/dsfield.h>
> +#include <net/inet_ecn.h>
> +#include <net/net_namespace.h>
> +#include <net/netns/generic.h>
> +#include <net/vxlan.h>
> 
> #include "datapath.h"
> #include "tunnel.h"
> #include "vport.h"
> 
> -#define VXLAN_FLAGS 0x08000000  /* struct vxlanhdr.vx_flags required value. */
> -
> -/**
> - * struct vxlanhdr - VXLAN header
> - * @vx_flags: Must have the exact value %VXLAN_FLAGS.
> - * @vx_vni: VXLAN Network Identifier (VNI) in top 24 bits, low 8 bits zeroed.
> - */
> -struct vxlanhdr {
> -	__be32 vx_flags;
> -	__be32 vx_vni;
> -};
> -
> -#define VXLAN_HLEN (sizeof(struct udphdr) + sizeof(struct vxlanhdr))
> +#define OVS_VXLAN_RCV_PRIORITY		8
> 
> /**
>  * struct vxlan_port - Keeps track of open UDP ports
> - * @dst_port: vxlan UDP port no.
> - * @list: list element in @vxlan_ports.
> - * @vxlan_rcv_socket: The socket created for this port number.
> + * @vh: vxlan_handler created for the port.
>  * @name: vport name.
>  */
> struct vxlan_port {
> -	__be16 dst_port;
> -	struct list_head list;
> -	struct socket *vxlan_rcv_socket;
> +	struct vxlan_handler *vh;
> 	char name[IFNAMSIZ];
> };
> 
> -static LIST_HEAD(vxlan_ports);
> -
> static inline struct vxlan_port *vxlan_vport(const struct vport *vport)
> {
> 	return vport_priv(vport);
> }
> 
> -static struct vxlan_port *vxlan_find_port(struct net *net, __be16 port)
> -{
> -	struct vxlan_port *vxlan_port;
> -
> -	list_for_each_entry_rcu(vxlan_port, &vxlan_ports, list) {
> -
> -		if (vxlan_port->dst_port == port &&
> -			net_eq(sock_net(vxlan_port->vxlan_rcv_socket->sk), net))
> -			return vxlan_port;
> -	}
> -
> -	return NULL;
> -}
> -
> -static inline struct vxlanhdr *vxlan_hdr(const struct sk_buff *skb)
> -{
> -	return (struct vxlanhdr *)(udp_hdr(skb) + 1);
> -}
> -
> -static void vxlan_build_header(const struct vport *vport,
> -			       struct sk_buff *skb,
> -			       int tunnel_hlen)
> -{
> -	struct vxlan_port *vxlan_port = vxlan_vport(vport);
> -	struct udphdr *udph = udp_hdr(skb);
> -	struct vxlanhdr *vxh = (struct vxlanhdr *)(udph + 1);
> -	const struct ovs_key_ipv4_tunnel *tun_key = OVS_CB(skb)->tun_key;
> -
> -	udph->dest = vxlan_port->dst_port;
> -	udph->source = htons(ovs_tnl_get_src_port(skb));
> -	udph->check = 0;
> -	udph->len = htons(skb->len - skb_transport_offset(skb));
> -
> -	vxh->vx_flags = htonl(VXLAN_FLAGS);
> -	vxh->vx_vni = htonl(be64_to_cpu(tun_key->tun_id) << 8);
> -}
> -
> /* Called with rcu_read_lock and BH disabled. */
> -static int vxlan_rcv(struct sock *sk, struct sk_buff *skb)
> +static int vxlan_rcv(struct vxlan_handler *vh, struct sk_buff *skb, __be32 vx_vni)
> {
> -	struct vxlan_port *vxlan_vport;
> -	struct vxlanhdr *vxh;
> +	struct vport *vport = vh->data;
> 	struct iphdr *iph;
> 	struct ovs_key_ipv4_tunnel tun_key;
> 	__be64 key;
> 
> -	vxlan_vport = vxlan_find_port(dev_net(skb->dev), udp_hdr(skb)->dest);
> -	if (unlikely(!vxlan_vport))
> -		goto error;
> -
> -	if (unlikely(!pskb_may_pull(skb, VXLAN_HLEN + ETH_HLEN)))
> -		goto error;
> -
> -	vxh = vxlan_hdr(skb);
> -	if (unlikely(vxh->vx_flags != htonl(VXLAN_FLAGS) ||
> -		     vxh->vx_vni & htonl(0xff)))
> -		goto error;
> -
> -	skb_pull_rcsum(skb, VXLAN_HLEN);
> -
> -	key = cpu_to_be64(ntohl(vxh->vx_vni) >> 8);
> -
> 	/* Save outer tunnel values */
> 	iph = ip_hdr(skb);
> +	key = cpu_to_be64(ntohl(vx_vni) >> 8);
> 	tnl_tun_key_init(&tun_key, iph, key, TUNNEL_KEY);
> 
> -	ovs_tnl_rcv(vport_from_priv(vxlan_vport), skb, &tun_key);
> -	goto out;
> -
> -error:
> -	kfree_skb(skb);
> -out:
> -	return 0;
> -}
> -
> -/* Random value.  Irrelevant as long as it's not 0 since we set the handler. */
> -#define UDP_ENCAP_VXLAN 1
> -static int vxlan_socket_init(struct vxlan_port *vxlan_port, struct net *net)
> -{
> -	struct sockaddr_in sin;
> -	int err;
> -
> -	err = sock_create_kern(AF_INET, SOCK_DGRAM, 0,
> -			       &vxlan_port->vxlan_rcv_socket);
> -	if (err)
> -		goto error;
> -
> -	/* release net ref. */
> -	sk_change_net(vxlan_port->vxlan_rcv_socket->sk, net);
> -
> -	sin.sin_family = AF_INET;
> -	sin.sin_addr.s_addr = htonl(INADDR_ANY);
> -	sin.sin_port = vxlan_port->dst_port;
> -
> -	err = kernel_bind(vxlan_port->vxlan_rcv_socket, (struct sockaddr *)&sin,
> -			  sizeof(struct sockaddr_in));
> -	if (err)
> -		goto error_sock;
> -
> -	udp_sk(vxlan_port->vxlan_rcv_socket->sk)->encap_type = UDP_ENCAP_VXLAN;
> -	udp_sk(vxlan_port->vxlan_rcv_socket->sk)->encap_rcv = vxlan_rcv;
> -
> -	udp_encap_enable();
> -
> -	return 0;
> -
> -error_sock:
> -	sk_release_kernel(vxlan_port->vxlan_rcv_socket->sk);
> -error:
> -	pr_warn("cannot register vxlan protocol handler\n");
> -	return err;
> +	ovs_vport_receive(vport, skb, &tun_key);
> +	return PACKET_RCVD;
> }
> 
> static int vxlan_get_options(const struct vport *vport, struct sk_buff *skb)
> {
> 	struct vxlan_port *vxlan_port = vxlan_vport(vport);
> +	__be16 dst_port = inet_sport(vxlan_port->vh->vs->sock->sk);
> 
> -	if (nla_put_u16(skb, OVS_TUNNEL_ATTR_DST_PORT, ntohs(vxlan_port->dst_port)))
> +	if (nla_put_u16(skb, OVS_TUNNEL_ATTR_DST_PORT, ntohs(dst_port)))
> 		return -EMSGSIZE;
> 	return 0;
> }
> @@ -197,9 +93,7 @@ static void vxlan_tnl_destroy(struct vport *vport)
> {
> 	struct vxlan_port *vxlan_port = vxlan_vport(vport);
> 
> -	list_del_rcu(&vxlan_port->list);
> -	/* Release socket */
> -	sk_release_kernel(vxlan_port->vxlan_rcv_socket->sk);
> +	vxlan_handler_put(vxlan_port->vh);
> 
> 	ovs_vport_deferred_free(vport);
> }
> @@ -209,10 +103,11 @@ static struct vport *vxlan_tnl_create(const struct vport_parms *parms)
> 	struct net *net = ovs_dp_get_net(parms->dp);
> 	struct nlattr *options = parms->options;
> 	struct vxlan_port *vxlan_port;
> +	struct vxlan_handler *vh;
> 	struct vport *vport;
> 	struct nlattr *a;
> -	int err;
> 	u16 dst_port;
> +	int err;
> 
> 	if (!options) {
> 		err = -EINVAL;
> @@ -227,41 +122,79 @@ static struct vport *vxlan_tnl_create(const struct vport_parms *parms)
> 		goto error;
> 	}
> 
> -	/* Verify if we already have a socket created for this port */
> -	if (vxlan_find_port(net, htons(dst_port))) {
> -		err = -EEXIST;
> -		goto error;
> -	}
> -
> 	vport = ovs_vport_alloc(sizeof(struct vxlan_port),
> 				&ovs_vxlan_vport_ops, parms);
> 	if (IS_ERR(vport))
> 		return vport;
> 
> 	vxlan_port = vxlan_vport(vport);
> -	vxlan_port->dst_port = htons(dst_port);
> 	strncpy(vxlan_port->name, parms->name, IFNAMSIZ);
> 
> -	err = vxlan_socket_init(vxlan_port, net);
> -	if (err)
> -		goto error_free;
> +	vh = vxlan_handler_add(net, htons(dst_port), vxlan_rcv,
> +			       vport, OVS_VXLAN_RCV_PRIORITY, true);
> +	if (IS_ERR(vh)) {
> +		ovs_vport_free(vport);
> +		return (void *)vh;
> +	}
> +	vxlan_port->vh = vh;
> 
> -	list_add_tail_rcu(&vxlan_port->list, &vxlan_ports);
> 	return vport;
> 
> -error_free:
> -	ovs_vport_free(vport);
> error:
> 	return ERR_PTR(err);
> }
> 
> static int vxlan_tnl_send(struct vport *vport, struct sk_buff *skb)
> {
> -	if (unlikely(!OVS_CB(skb)->tun_key))
> -		return -EINVAL;
> +	struct vxlan_port *vxlan_port = vxlan_vport(vport);
> +	__be16 dst_port = inet_sport(vxlan_port->vh->vs->sock->sk);
> +	struct net *net = ovs_dp_get_net(vport->dp);
> +	struct rtable *rt;
> +	__be16 src_port;
> +	__be32 saddr;
> +	__be16 df;
> +	int port_min;
> +	int port_max;
> +	int err;
> +
> +	if (unlikely(!OVS_CB(skb)->tun_key)) {
> +		err = -EINVAL;
> +		goto error;
> +	}
> 
> -	return ovs_tnl_send(vport, skb, IPPROTO_UDP,
> -			VXLAN_HLEN, vxlan_build_header);
> +	forward_ip_summed(skb, true);
> +
> +	/* Route lookup */
> +	saddr = OVS_CB(skb)->tun_key->ipv4_src;
> +	rt = find_route(ovs_dp_get_net(vport->dp),
> +			&saddr,
> +			OVS_CB(skb)->tun_key->ipv4_dst,
> +			IPPROTO_UDP,
> +			OVS_CB(skb)->tun_key->ipv4_tos,
> +			skb_get_mark(skb));
> +	if (IS_ERR(rt)) {
> +		err = PTR_ERR(rt);
> +		goto error;
> +	}
> +
> +	df = OVS_CB(skb)->tun_key->tun_flags & TUNNEL_DONT_FRAGMENT ?
> +		htons(IP_DF) : 0;
> +
> +	skb->local_df = 1;
> +
> +	inet_get_local_port_range(&port_min, &port_max);
> +	src_port = vxlan_src_port(port_min, port_max, skb);
> +
> +	err = vxlan_xmit_skb(net, vxlan_port->vh, rt, skb,
> +			     saddr, OVS_CB(skb)->tun_key->ipv4_dst,
> +			     OVS_CB(skb)->tun_key->ipv4_tos,
> +			     OVS_CB(skb)->tun_key->ipv4_ttl, df,
> +			     src_port, dst_port,
> +			     htonl(be64_to_cpu(OVS_CB(skb)->tun_key->tun_id) << 8));
> +	if (err < 0)
> +		ip_rt_put(rt);
> +error:
> +	return err;
> }
> 
> static const char *vxlan_get_name(const struct vport *vport)
> -- 
> 1.7.1
> 
> _______________________________________________
> dev mailing list
> dev at openvswitch.org
> http://openvswitch.org/mailman/listinfo/dev




More information about the dev mailing list