[deliverable/linux.git] / net / core / flow_dissector.c

#include <linux/skbuff.h>
#include <linux/export.h>
#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>

/* 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));
}

/**
 * skb_flow_get_ports - extract the upper layer ports and return them
 * @skb: buffer to extract the ports from
 * @thoff: transport header offset
 * @ip_proto: protocol for which to get port offset
 *
 * The function will try to retrieve the ports at offset thoff + poff where poff
 * is the protocol port offset returned from proto_ports_offset
 */
__be32 skb_flow_get_ports(const struct sk_buff *skb, int thoff, u8 ip_proto)
{
	int poff = proto_ports_offset(ip_proto);

	if (poff >= 0) {
		__be32 *ports, _ports;

		ports = skb_header_pointer(skb, thoff + poff,
					   sizeof(_ports), &_ports);
		if (ports)
			return *ports;
	}

	return 0;
}
EXPORT_SYMBOL(skb_flow_get_ports);

bool skb_flow_dissect(const struct sk_buff *skb, struct flow_keys *flow)
{
	int nhoff = skb_network_offset(skb);
	u8 ip_proto;
	__be16 proto = skb->protocol;

	memset(flow, 0, sizeof(*flow));

again:
	switch (proto) {
	case htons(ETH_P_IP): {
		const struct iphdr *iph;
		struct iphdr _iph;
ip:
		iph = skb_header_pointer(skb, nhoff, sizeof(_iph), &_iph);
		if (!iph || iph->ihl < 5)
			return false;
		nhoff += iph->ihl * 4;

		ip_proto = iph->protocol;
		if (ip_is_fragment(iph))
			ip_proto = 0;

		iph_to_flow_copy_addrs(flow, iph);
		break;
	}
	case htons(ETH_P_IPV6): {
		const struct ipv6hdr *iph;
		struct ipv6hdr _iph;
		__be32 flow_label;

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);

		flow_label = ip6_flowlabel(iph);
		if (flow_label) {
			/* Awesome, IPv6 packet has a flow label so we can
			 * use that to represent the ports without any
			 * further dissection.
			 */
			flow->n_proto = proto;
			flow->ip_proto = ip_proto;
			flow->ports = flow_label;
			flow->thoff = (u16)nhoff;

			return true;
		}

		break;
	}
	case htons(ETH_P_8021AD):
	case 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 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 htons(PPP_IP):
			goto ip;
		case 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:
		proto = htons(ETH_P_IP);
		goto ip;
	case IPPROTO_IPV6:
		proto = htons(ETH_P_IPV6);
		goto ipv6;
	default:
		break;
	}

	flow->n_proto = proto;
	flow->ip_proto = ip_proto;
	flow->ports = skb_flow_get_ports(skb, nhoff, ip_proto);
	flow->thoff = (u16) nhoff;

	return true;
}
EXPORT_SYMBOL(skb_flow_dissect);

static u32 hashrnd __read_mostly;
static __always_inline void __flow_hash_secret_init(void)
{
	net_get_random_once(&hashrnd, sizeof(hashrnd));
}

static __always_inline u32 __flow_hash_3words(u32 a, u32 b, u32 c)
{
	__flow_hash_secret_init();
	return jhash_3words(a, b, c, hashrnd);
}

static inline u32 __flow_hash_from_keys(struct flow_keys *keys)
{
	u32 hash;

	/* 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]);
	}

	hash = __flow_hash_3words((__force u32)keys->dst,
				  (__force u32)keys->src,
				  (__force u32)keys->ports);
	if (!hash)
		hash = 1;

	return hash;
}

u32 flow_hash_from_keys(struct flow_keys *keys)
{
	return __flow_hash_from_keys(keys);
}
EXPORT_SYMBOL(flow_hash_from_keys);

/*
 * __skb_get_hash: calculate a flow hash based on src/dst addresses
 * and src/dst port numbers.  Sets hash in skb to non-zero hash value
 * on success, zero indicates no valid hash.  Also, sets l4_hash in skb
 * if hash is a canonical 4-tuple hash over transport ports.
 */
void __skb_get_hash(struct sk_buff *skb)
{
	struct flow_keys keys;

	if (!skb_flow_dissect(skb, &keys))
		return;

	if (keys.ports)
		skb->l4_hash = 1;

	skb->sw_hash = 1;

	skb->hash = __flow_hash_from_keys(&keys);
}
EXPORT_SYMBOL(__skb_get_hash);

/*
 * Returns a Tx hash based on the given packet descriptor a Tx queues' number
 * to be used as a distribution range.
 */
u16 __skb_tx_hash(const struct net_device *dev, struct sk_buff *skb,
		  unsigned int num_tx_queues)
{
	u32 hash;
	u16 qoffset = 0;
	u16 qcount = num_tx_queues;

	if (skb_rx_queue_recorded(skb)) {
		hash = skb_get_rx_queue(skb);
		while (unlikely(hash >= num_tx_queues))
			hash -= num_tx_queues;
		return hash;
	}

	if (dev->num_tc) {
		u8 tc = netdev_get_prio_tc_map(dev, skb->priority);
		qoffset = dev->tc_to_txq[tc].offset;
		qcount = dev->tc_to_txq[tc].count;
	}

	return (u16) (((u64)skb_get_hash(skb) * qcount) >> 32) + qoffset;
}
EXPORT_SYMBOL(__skb_tx_hash);

/* __skb_get_poff() returns the offset to the payload as far as it could
 * be dissected. The main user is currently BPF, so that we can dynamically
 * truncate packets without needing to push actual payload to the user
 * space and can analyze headers only, instead.
 */
u32 __skb_get_poff(const struct sk_buff *skb)
{
	struct flow_keys keys;
	u32 poff = 0;

	if (!skb_flow_dissect(skb, &keys))
		return 0;

	poff += keys.thoff;
	switch (keys.ip_proto) {
	case IPPROTO_TCP: {
		const struct tcphdr *tcph;
		struct tcphdr _tcph;

		tcph = skb_header_pointer(skb, poff, sizeof(_tcph), &_tcph);
		if (!tcph)
			return poff;

		poff += max_t(u32, sizeof(struct tcphdr), tcph->doff * 4);
		break;
	}
	case IPPROTO_UDP:
	case IPPROTO_UDPLITE:
		poff += sizeof(struct udphdr);
		break;
	/* For the rest, we do not really care about header
	 * extensions at this point for now.
	 */
	case IPPROTO_ICMP:
		poff += sizeof(struct icmphdr);
		break;
	case IPPROTO_ICMPV6:
		poff += sizeof(struct icmp6hdr);
		break;
	case IPPROTO_IGMP:
		poff += sizeof(struct igmphdr);
		break;
	case IPPROTO_DCCP:
		poff += sizeof(struct dccp_hdr);
		break;
	case IPPROTO_SCTP:
		poff += sizeof(struct sctphdr);
		break;
	}

	return poff;
}

static inline int get_xps_queue(struct net_device *dev, struct sk_buff *skb)
{
#ifdef CONFIG_XPS
	struct xps_dev_maps *dev_maps;
	struct xps_map *map;
	int queue_index = -1;

	rcu_read_lock();
	dev_maps = rcu_dereference(dev->xps_maps);
	if (dev_maps) {
		map = rcu_dereference(
		    dev_maps->cpu_map[raw_smp_processor_id()]);
		if (map) {
			if (map->len == 1)
				queue_index = map->queues[0];
			else
				queue_index = map->queues[
				    ((u64)skb_get_hash(skb) * map->len) >> 32];

			if (unlikely(queue_index >= dev->real_num_tx_queues))
				queue_index = -1;
		}
	}
	rcu_read_unlock();

	return queue_index;
#else
	return -1;
#endif
}

static u16 __netdev_pick_tx(struct net_device *dev, struct sk_buff *skb)
{
	struct sock *sk = skb->sk;
	int queue_index = sk_tx_queue_get(sk);

	if (queue_index < 0 || skb->ooo_okay ||
	    queue_index >= dev->real_num_tx_queues) {
		int new_index = get_xps_queue(dev, skb);
		if (new_index < 0)
			new_index = skb_tx_hash(dev, skb);

		if (queue_index != new_index && sk &&
		    rcu_access_pointer(sk->sk_dst_cache))
			sk_tx_queue_set(sk, new_index);

		queue_index = new_index;
	}

	return queue_index;
}

struct netdev_queue *netdev_pick_tx(struct net_device *dev,
				    struct sk_buff *skb,
				    void *accel_priv)
{
	int queue_index = 0;

	if (dev->real_num_tx_queues != 1) {
		const struct net_device_ops *ops = dev->netdev_ops;
		if (ops->ndo_select_queue)
			queue_index = ops->ndo_select_queue(dev, skb, accel_priv,
							    __netdev_pick_tx);
		else
			queue_index = __netdev_pick_tx(dev, skb);

		if (!accel_priv)
			queue_index = netdev_cap_txqueue(dev, queue_index);
	}

	skb_set_queue_mapping(skb, queue_index);
	return netdev_get_tx_queue(dev, queue_index);
}
Commit	Line	Data
0744dd00	1	#include <linux/skbuff.h>
c452ed70	2	#include <linux/export.h>
0744dd00 ED	3	#include <linux/ip.h>
	4	#include <linux/ipv6.h>
	5	#include <linux/if_vlan.h>
	6	#include <net/ip.h>
ddbe5032	7	#include <net/ipv6.h>
f77668dc DB	8	#include <linux/igmp.h>
	9	#include <linux/icmp.h>
	10	#include <linux/sctp.h>
	11	#include <linux/dccp.h>
0744dd00 ED	12	#include <linux/if_tunnel.h>
	13	#include <linux/if_pppox.h>
	14	#include <linux/ppp_defs.h>
	15	#include <net/flow_keys.h>
	16
4d77d2b5 ED	17	/* copy saddr & daddr, possibly using 64bit load/store
	18	* Equivalent to : flow->src = iph->saddr;
	19	* flow->dst = iph->daddr;
	20	*/
	21	static void iph_to_flow_copy_addrs(struct flow_keys flow, const struct iphdr iph)
	22	{
	23	BUILD_BUG_ON(offsetof(typeof(*flow), dst) !=
	24	offsetof(typeof(*flow), src) + sizeof(flow->src));
	25	memcpy(&flow->src, &iph->saddr, sizeof(flow->src) + sizeof(flow->dst));
	26	}
0744dd00	27
357afe9c NA	28	/**
	29	* skb_flow_get_ports - extract the upper layer ports and return them
	30	* @skb: buffer to extract the ports from
	31	* @thoff: transport header offset
	32	* @ip_proto: protocol for which to get port offset
	33	*
	34	* The function will try to retrieve the ports at offset thoff + poff where poff
	35	* is the protocol port offset returned from proto_ports_offset
	36	*/
	37	__be32 skb_flow_get_ports(const struct sk_buff *skb, int thoff, u8 ip_proto)
	38	{
	39	int poff = proto_ports_offset(ip_proto);
	40
	41	if (poff >= 0) {
	42	__be32 *ports, _ports;
	43
	44	ports = skb_header_pointer(skb, thoff + poff,
	45	sizeof(_ports), &_ports);
	46	if (ports)
	47	return *ports;
	48	}
	49
	50	return 0;
	51	}
	52	EXPORT_SYMBOL(skb_flow_get_ports);
	53
0744dd00 ED	54	bool skb_flow_dissect(const struct sk_buff skb, struct flow_keys flow)
0744dd00 ED	55	{
357afe9c	56	int nhoff = skb_network_offset(skb);
0744dd00 ED	57	u8 ip_proto;
	58	__be16 proto = skb->protocol;
	59
	60	memset(flow, 0, sizeof(*flow));
	61
	62	again:
	63	switch (proto) {
2b8837ae	64	case htons(ETH_P_IP): {
0744dd00 ED	65	const struct iphdr *iph;
	66	struct iphdr _iph;
	67	ip:
	68	iph = skb_header_pointer(skb, nhoff, sizeof(_iph), &_iph);
6f092343	69	if (!iph \|\| iph->ihl < 5)
0744dd00	70	return false;
3797d3e8	71	nhoff += iph->ihl * 4;
0744dd00	72
3797d3e8	73	ip_proto = iph->protocol;
0744dd00 ED	74	if (ip_is_fragment(iph))
0744dd00 ED	75	ip_proto = 0;
3797d3e8	76
4d77d2b5	77	iph_to_flow_copy_addrs(flow, iph);
0744dd00 ED	78	break;
0744dd00 ED	79	}
2b8837ae	80	case htons(ETH_P_IPV6): {
0744dd00 ED	81	const struct ipv6hdr *iph;
0744dd00 ED	82	struct ipv6hdr _iph;
19469a87 TH	83	__be32 flow_label;
19469a87 TH	84
0744dd00 ED	85	ipv6:
	86	iph = skb_header_pointer(skb, nhoff, sizeof(_iph), &_iph);
	87	if (!iph)
	88	return false;
	89
	90	ip_proto = iph->nexthdr;
ddbe5032 ED	91	flow->src = (__force __be32)ipv6_addr_hash(&iph->saddr);
ddbe5032 ED	92	flow->dst = (__force __be32)ipv6_addr_hash(&iph->daddr);
0744dd00	93	nhoff += sizeof(struct ipv6hdr);
19469a87 TH	94
	95	flow_label = ip6_flowlabel(iph);
	96	if (flow_label) {
	97	/* Awesome, IPv6 packet has a flow label so we can
	98	* use that to represent the ports without any
	99	* further dissection.
	100	*/
	101	flow->n_proto = proto;
	102	flow->ip_proto = ip_proto;
	103	flow->ports = flow_label;
	104	flow->thoff = (u16)nhoff;
	105
	106	return true;
	107	}
	108
0744dd00 ED	109	break;
0744dd00 ED	110	}
2b8837ae JP	111	case htons(ETH_P_8021AD):
2b8837ae JP	112	case htons(ETH_P_8021Q): {
0744dd00 ED	113	const struct vlan_hdr *vlan;
	114	struct vlan_hdr _vlan;
	115
	116	vlan = skb_header_pointer(skb, nhoff, sizeof(_vlan), &_vlan);
	117	if (!vlan)
	118	return false;
	119
	120	proto = vlan->h_vlan_encapsulated_proto;
	121	nhoff += sizeof(*vlan);
	122	goto again;
	123	}
2b8837ae	124	case htons(ETH_P_PPP_SES): {
0744dd00 ED	125	struct {
	126	struct pppoe_hdr hdr;
	127	__be16 proto;
	128	} *hdr, _hdr;
	129	hdr = skb_header_pointer(skb, nhoff, sizeof(_hdr), &_hdr);
	130	if (!hdr)
	131	return false;
	132	proto = hdr->proto;
	133	nhoff += PPPOE_SES_HLEN;
	134	switch (proto) {
2b8837ae	135	case htons(PPP_IP):
0744dd00	136	goto ip;
2b8837ae	137	case htons(PPP_IPV6):
0744dd00 ED	138	goto ipv6;
	139	default:
	140	return false;
	141	}
	142	}
	143	default:
	144	return false;
	145	}
	146
	147	switch (ip_proto) {
	148	case IPPROTO_GRE: {
	149	struct gre_hdr {
	150	__be16 flags;
	151	__be16 proto;
	152	} *hdr, _hdr;
	153
	154	hdr = skb_header_pointer(skb, nhoff, sizeof(_hdr), &_hdr);
	155	if (!hdr)
	156	return false;
	157	/*
	158	* Only look inside GRE if version zero and no
	159	* routing
	160	*/
	161	if (!(hdr->flags & (GRE_VERSION\|GRE_ROUTING))) {
	162	proto = hdr->proto;
	163	nhoff += 4;
	164	if (hdr->flags & GRE_CSUM)
	165	nhoff += 4;
	166	if (hdr->flags & GRE_KEY)
	167	nhoff += 4;
	168	if (hdr->flags & GRE_SEQ)
	169	nhoff += 4;
e1733de2 MD	170	if (proto == htons(ETH_P_TEB)) {
	171	const struct ethhdr *eth;
	172	struct ethhdr _eth;
	173
	174	eth = skb_header_pointer(skb, nhoff,
	175	sizeof(_eth), &_eth);
	176	if (!eth)
	177	return false;
	178	proto = eth->h_proto;
	179	nhoff += sizeof(*eth);
	180	}
0744dd00 ED	181	goto again;
	182	}
	183	break;
	184	}
	185	case IPPROTO_IPIP:
fca41895 TH	186	proto = htons(ETH_P_IP);
fca41895 TH	187	goto ip;
b438f940 TH	188	case IPPROTO_IPV6:
	189	proto = htons(ETH_P_IPV6);
	190	goto ipv6;
0744dd00 ED	191	default:
	192	break;
	193	}
	194
e0f31d84	195	flow->n_proto = proto;
0744dd00	196	flow->ip_proto = ip_proto;
357afe9c	197	flow->ports = skb_flow_get_ports(skb, nhoff, ip_proto);
8ed78166 DB	198	flow->thoff = (u16) nhoff;
8ed78166 DB	199
0744dd00 ED	200	return true;
	201	}
	202	EXPORT_SYMBOL(skb_flow_dissect);
441d9d32 CW	203
441d9d32 CW	204	static u32 hashrnd __read_mostly;
66415cf8 HFS	205	static __always_inline void __flow_hash_secret_init(void)
	206	{
	207	net_get_random_once(&hashrnd, sizeof(hashrnd));
	208	}
	209
	210	static __always_inline u32 __flow_hash_3words(u32 a, u32 b, u32 c)
	211	{
	212	__flow_hash_secret_init();
	213	return jhash_3words(a, b, c, hashrnd);
	214	}
	215
5ed20a68 TH	216	static inline u32 __flow_hash_from_keys(struct flow_keys *keys)
	217	{
	218	u32 hash;
	219
	220	/* get a consistent hash (same value on both flow directions) */
	221	if (((__force u32)keys->dst < (__force u32)keys->src) \|\|
	222	(((__force u32)keys->dst == (__force u32)keys->src) &&
	223	((__force u16)keys->port16[1] < (__force u16)keys->port16[0]))) {
	224	swap(keys->dst, keys->src);
	225	swap(keys->port16[0], keys->port16[1]);
	226	}
	227
	228	hash = __flow_hash_3words((__force u32)keys->dst,
	229	(__force u32)keys->src,
	230	(__force u32)keys->ports);
	231	if (!hash)
	232	hash = 1;
	233
	234	return hash;
	235	}
	236
	237	u32 flow_hash_from_keys(struct flow_keys *keys)
	238	{
	239	return __flow_hash_from_keys(keys);
	240	}
	241	EXPORT_SYMBOL(flow_hash_from_keys);
	242
441d9d32	243	/*
3958afa1	244	* __skb_get_hash: calculate a flow hash based on src/dst addresses
61b905da TH	245	* and src/dst port numbers. Sets hash in skb to non-zero hash value
61b905da TH	246	* on success, zero indicates no valid hash. Also, sets l4_hash in skb
441d9d32 CW	247	* if hash is a canonical 4-tuple hash over transport ports.
441d9d32 CW	248	*/
3958afa1	249	void __skb_get_hash(struct sk_buff *skb)
441d9d32 CW	250	{
441d9d32 CW	251	struct flow_keys keys;
441d9d32 CW	252
	253	if (!skb_flow_dissect(skb, &keys))
	254	return;
	255
	256	if (keys.ports)
61b905da	257	skb->l4_hash = 1;
441d9d32	258
a3b18ddb TH	259	skb->sw_hash = 1;
a3b18ddb TH	260
5ed20a68	261	skb->hash = __flow_hash_from_keys(&keys);
441d9d32	262	}
3958afa1	263	EXPORT_SYMBOL(__skb_get_hash);
441d9d32 CW	264
	265	/*
	266	* Returns a Tx hash based on the given packet descriptor a Tx queues' number
	267	* to be used as a distribution range.
	268	*/
0e001614	269	u16 __skb_tx_hash(const struct net_device dev, struct sk_buff skb,
441d9d32 CW	270	unsigned int num_tx_queues)
	271	{
	272	u32 hash;
	273	u16 qoffset = 0;
	274	u16 qcount = num_tx_queues;
	275
	276	if (skb_rx_queue_recorded(skb)) {
	277	hash = skb_get_rx_queue(skb);
	278	while (unlikely(hash >= num_tx_queues))
	279	hash -= num_tx_queues;
	280	return hash;
	281	}
	282
	283	if (dev->num_tc) {
	284	u8 tc = netdev_get_prio_tc_map(dev, skb->priority);
	285	qoffset = dev->tc_to_txq[tc].offset;
	286	qcount = dev->tc_to_txq[tc].count;
	287	}
	288
0e001614	289	return (u16) (((u64)skb_get_hash(skb) * qcount) >> 32) + qoffset;
441d9d32 CW	290	}
	291	EXPORT_SYMBOL(__skb_tx_hash);
	292
f77668dc DB	293	/* __skb_get_poff() returns the offset to the payload as far as it could
	294	* be dissected. The main user is currently BPF, so that we can dynamically
	295	* truncate packets without needing to push actual payload to the user
	296	* space and can analyze headers only, instead.
	297	*/
	298	u32 __skb_get_poff(const struct sk_buff *skb)
	299	{
	300	struct flow_keys keys;
	301	u32 poff = 0;
	302
	303	if (!skb_flow_dissect(skb, &keys))
	304	return 0;
	305
	306	poff += keys.thoff;
	307	switch (keys.ip_proto) {
	308	case IPPROTO_TCP: {
	309	const struct tcphdr *tcph;
	310	struct tcphdr _tcph;
	311
	312	tcph = skb_header_pointer(skb, poff, sizeof(_tcph), &_tcph);
	313	if (!tcph)
	314	return poff;
	315
	316	poff += max_t(u32, sizeof(struct tcphdr), tcph->doff * 4);
	317	break;
	318	}
	319	case IPPROTO_UDP:
	320	case IPPROTO_UDPLITE:
	321	poff += sizeof(struct udphdr);
	322	break;
	323	/* For the rest, we do not really care about header
	324	* extensions at this point for now.
	325	*/
	326	case IPPROTO_ICMP:
	327	poff += sizeof(struct icmphdr);
	328	break;
	329	case IPPROTO_ICMPV6:
	330	poff += sizeof(struct icmp6hdr);
	331	break;
	332	case IPPROTO_IGMP:
	333	poff += sizeof(struct igmphdr);
	334	break;
	335	case IPPROTO_DCCP:
	336	poff += sizeof(struct dccp_hdr);
	337	break;
	338	case IPPROTO_SCTP:
	339	poff += sizeof(struct sctphdr);
	340	break;
	341	}
	342
	343	return poff;
	344	}
	345
441d9d32 CW	346	static inline int get_xps_queue(struct net_device dev, struct sk_buff skb)
	347	{
	348	#ifdef CONFIG_XPS
	349	struct xps_dev_maps *dev_maps;
	350	struct xps_map *map;
	351	int queue_index = -1;
	352
	353	rcu_read_lock();
	354	dev_maps = rcu_dereference(dev->xps_maps);
	355	if (dev_maps) {
	356	map = rcu_dereference(
	357	dev_maps->cpu_map[raw_smp_processor_id()]);
	358	if (map) {
	359	if (map->len == 1)
	360	queue_index = map->queues[0];
0e001614	361	else
441d9d32	362	queue_index = map->queues[
0e001614 TH	363	((u64)skb_get_hash(skb) * map->len) >> 32];
0e001614 TH	364
441d9d32 CW	365	if (unlikely(queue_index >= dev->real_num_tx_queues))
	366	queue_index = -1;
	367	}
	368	}
	369	rcu_read_unlock();
	370
	371	return queue_index;
	372	#else
	373	return -1;
	374	#endif
	375	}
	376
99932d4f	377	static u16 __netdev_pick_tx(struct net_device dev, struct sk_buff skb)
441d9d32 CW	378	{
	379	struct sock *sk = skb->sk;
	380	int queue_index = sk_tx_queue_get(sk);
	381
	382	if (queue_index < 0 \|\| skb->ooo_okay \|\|
	383	queue_index >= dev->real_num_tx_queues) {
	384	int new_index = get_xps_queue(dev, skb);
	385	if (new_index < 0)
	386	new_index = skb_tx_hash(dev, skb);
	387
702821f4 ED	388	if (queue_index != new_index && sk &&
702821f4 ED	389	rcu_access_pointer(sk->sk_dst_cache))
50d1784e	390	sk_tx_queue_set(sk, new_index);
441d9d32 CW	391
	392	queue_index = new_index;
	393	}
	394
	395	return queue_index;
	396	}
441d9d32 CW	397
441d9d32 CW	398	struct netdev_queue netdev_pick_tx(struct net_device dev,
f663dd9a JW	399	struct sk_buff *skb,
f663dd9a JW	400	void *accel_priv)
441d9d32 CW	401	{
	402	int queue_index = 0;
	403
	404	if (dev->real_num_tx_queues != 1) {
	405	const struct net_device_ops *ops = dev->netdev_ops;
	406	if (ops->ndo_select_queue)
99932d4f DB	407	queue_index = ops->ndo_select_queue(dev, skb, accel_priv,
99932d4f DB	408	__netdev_pick_tx);
441d9d32 CW	409	else
441d9d32 CW	410	queue_index = __netdev_pick_tx(dev, skb);
f663dd9a JW	411
f663dd9a JW	412	if (!accel_priv)
b9507bda	413	queue_index = netdev_cap_txqueue(dev, queue_index);
441d9d32 CW	414	}
	415
	416	skb_set_queue_mapping(skb, queue_index);
	417	return netdev_get_tx_queue(dev, queue_index);
	418	}