[GitHub/mt8127/android_kernel_alcatel_ttab.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/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));
}

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;
			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;
}
EXPORT_SYMBOL(skb_flow_dissect);

static u32 hashrnd __read_mostly;

/*
 * __skb_get_rxhash: calculate a flow hash based on src/dst addresses
 * and src/dst port numbers.  Sets rxhash in skb to non-zero hash value
 * on success, zero indicates no valid hash.  Also, sets l4_rxhash in skb
 * if hash is a canonical 4-tuple hash over transport ports.
 */
void __skb_get_rxhash(struct sk_buff *skb)
{
	struct flow_keys keys;
	u32 hash;

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

	if (keys.ports)
		skb->l4_rxhash = 1;

	/* 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 = jhash_3words((__force u32)keys.dst,
			    (__force u32)keys.src,
			    (__force u32)keys.ports, hashrnd);
	if (!hash)
		hash = 1;

	skb->rxhash = hash;
}
EXPORT_SYMBOL(__skb_get_rxhash);

/*
 * 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, const 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;
	}

	if (skb->sk && skb->sk->sk_hash)
		hash = skb->sk->sk_hash;
	else
		hash = (__force u16) skb->protocol;
	hash = jhash_1word(hash, hashrnd);

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

static inline u16 dev_cap_txqueue(struct net_device *dev, u16 queue_index)
{
	if (unlikely(queue_index >= dev->real_num_tx_queues)) {
		net_warn_ratelimited("%s selects TX queue %d, but real number of TX queues is %d\n",
				     dev->name, queue_index,
				     dev->real_num_tx_queues);
		return 0;
	}
	return queue_index;
}

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 {
				u32 hash;
				if (skb->sk && skb->sk->sk_hash)
					hash = skb->sk->sk_hash;
				else
					hash = (__force u16) skb->protocol ^
					    skb->rxhash;
				hash = jhash_1word(hash, hashrnd);
				queue_index = map->queues[
				    ((u64)hash * 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
}

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) {
			struct dst_entry *dst =
				    rcu_dereference_check(sk->sk_dst_cache, 1);

			if (dst && skb_dst(skb) == dst)
				sk_tx_queue_set(sk, queue_index);

		}

		queue_index = new_index;
	}

	return queue_index;
}
EXPORT_SYMBOL(__netdev_pick_tx);

struct netdev_queue *netdev_pick_tx(struct net_device *dev,
				    struct sk_buff *skb)
{
	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);
		else
			queue_index = __netdev_pick_tx(dev, skb);
		queue_index = dev_cap_txqueue(dev, queue_index);
	}

	skb_set_queue_mapping(skb, queue_index);
	return netdev_get_tx_queue(dev, queue_index);
}

static int __init initialize_hashrnd(void)
{
	get_random_bytes(&hashrnd, sizeof(hashrnd));
	return 0;
}

late_initcall_sync(initialize_hashrnd);
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>
0744dd00 ED	8	#include <linux/if_tunnel.h>
	9	#include <linux/if_pppox.h>
	10	#include <linux/ppp_defs.h>
	11	#include <net/flow_keys.h>
	12
4d77d2b5 ED	13	/* copy saddr & daddr, possibly using 64bit load/store
	14	* Equivalent to : flow->src = iph->saddr;
	15	* flow->dst = iph->daddr;
	16	*/
	17	static void iph_to_flow_copy_addrs(struct flow_keys flow, const struct iphdr iph)
	18	{
	19	BUILD_BUG_ON(offsetof(typeof(*flow), dst) !=
	20	offsetof(typeof(*flow), src) + sizeof(flow->src));
	21	memcpy(&flow->src, &iph->saddr, sizeof(flow->src) + sizeof(flow->dst));
	22	}
0744dd00 ED	23
	24	bool skb_flow_dissect(const struct sk_buff skb, struct flow_keys flow)
	25	{
	26	int poff, nhoff = skb_network_offset(skb);
	27	u8 ip_proto;
	28	__be16 proto = skb->protocol;
	29
	30	memset(flow, 0, sizeof(*flow));
	31
	32	again:
	33	switch (proto) {
	34	case __constant_htons(ETH_P_IP): {
	35	const struct iphdr *iph;
	36	struct iphdr _iph;
	37	ip:
	38	iph = skb_header_pointer(skb, nhoff, sizeof(_iph), &_iph);
	39	if (!iph)
	40	return false;
	41
	42	if (ip_is_fragment(iph))
	43	ip_proto = 0;
	44	else
	45	ip_proto = iph->protocol;
4d77d2b5	46	iph_to_flow_copy_addrs(flow, iph);
0744dd00 ED	47	nhoff += iph->ihl * 4;
	48	break;
	49	}
	50	case __constant_htons(ETH_P_IPV6): {
	51	const struct ipv6hdr *iph;
	52	struct ipv6hdr _iph;
	53	ipv6:
	54	iph = skb_header_pointer(skb, nhoff, sizeof(_iph), &_iph);
	55	if (!iph)
	56	return false;
	57
	58	ip_proto = iph->nexthdr;
ddbe5032 ED	59	flow->src = (__force __be32)ipv6_addr_hash(&iph->saddr);
ddbe5032 ED	60	flow->dst = (__force __be32)ipv6_addr_hash(&iph->daddr);
0744dd00 ED	61	nhoff += sizeof(struct ipv6hdr);
	62	break;
	63	}
	64	case __constant_htons(ETH_P_8021Q): {
	65	const struct vlan_hdr *vlan;
	66	struct vlan_hdr _vlan;
	67
	68	vlan = skb_header_pointer(skb, nhoff, sizeof(_vlan), &_vlan);
	69	if (!vlan)
	70	return false;
	71
	72	proto = vlan->h_vlan_encapsulated_proto;
	73	nhoff += sizeof(*vlan);
	74	goto again;
	75	}
	76	case __constant_htons(ETH_P_PPP_SES): {
	77	struct {
	78	struct pppoe_hdr hdr;
	79	__be16 proto;
	80	} *hdr, _hdr;
	81	hdr = skb_header_pointer(skb, nhoff, sizeof(_hdr), &_hdr);
	82	if (!hdr)
	83	return false;
	84	proto = hdr->proto;
	85	nhoff += PPPOE_SES_HLEN;
	86	switch (proto) {
	87	case __constant_htons(PPP_IP):
	88	goto ip;
	89	case __constant_htons(PPP_IPV6):
	90	goto ipv6;
	91	default:
	92	return false;
	93	}
	94	}
	95	default:
	96	return false;
	97	}
	98
	99	switch (ip_proto) {
	100	case IPPROTO_GRE: {
	101	struct gre_hdr {
	102	__be16 flags;
	103	__be16 proto;
	104	} *hdr, _hdr;
	105
	106	hdr = skb_header_pointer(skb, nhoff, sizeof(_hdr), &_hdr);
	107	if (!hdr)
	108	return false;
	109	/*
	110	* Only look inside GRE if version zero and no
	111	* routing
	112	*/
	113	if (!(hdr->flags & (GRE_VERSION\|GRE_ROUTING))) {
	114	proto = hdr->proto;
	115	nhoff += 4;
	116	if (hdr->flags & GRE_CSUM)
	117	nhoff += 4;
	118	if (hdr->flags & GRE_KEY)
	119	nhoff += 4;
	120	if (hdr->flags & GRE_SEQ)
	121	nhoff += 4;
	122	goto again;
	123	}
	124	break;
125	}
126	case IPPROTO_IPIP:
127	goto again;
128	default:
129	break;
130	}
131
132	flow->ip_proto = ip_proto;
133	poff = proto_ports_offset(ip_proto);
134	if (poff >= 0) {
135	__be32 *ports, _ports;
136
137	nhoff += poff;
138	ports = skb_header_pointer(skb, nhoff, sizeof(_ports), &_ports);
139	if (ports)
140	flow->ports = *ports;
141	}
142
8ed78166 DB	143	flow->thoff = (u16) nhoff;
8ed78166 DB	144
0744dd00 ED	145	return true;
	146	}
	147	EXPORT_SYMBOL(skb_flow_dissect);
441d9d32 CW	148
	149	static u32 hashrnd __read_mostly;
	150
	151	/*
	152	* __skb_get_rxhash: calculate a flow hash based on src/dst addresses
	153	* and src/dst port numbers. Sets rxhash in skb to non-zero hash value
	154	* on success, zero indicates no valid hash. Also, sets l4_rxhash in skb
	155	* if hash is a canonical 4-tuple hash over transport ports.
	156	*/
	157	void __skb_get_rxhash(struct sk_buff *skb)
	158	{
	159	struct flow_keys keys;
	160	u32 hash;
	161
	162	if (!skb_flow_dissect(skb, &keys))
	163	return;
	164
	165	if (keys.ports)
	166	skb->l4_rxhash = 1;
	167
	168	/* get a consistent hash (same value on both flow directions) */
	169	if (((__force u32)keys.dst < (__force u32)keys.src) \|\|
	170	(((__force u32)keys.dst == (__force u32)keys.src) &&
	171	((__force u16)keys.port16[1] < (__force u16)keys.port16[0]))) {
	172	swap(keys.dst, keys.src);
	173	swap(keys.port16[0], keys.port16[1]);
	174	}
	175
	176	hash = jhash_3words((__force u32)keys.dst,
	177	(__force u32)keys.src,
	178	(__force u32)keys.ports, hashrnd);
	179	if (!hash)
	180	hash = 1;
	181
	182	skb->rxhash = hash;
	183	}
	184	EXPORT_SYMBOL(__skb_get_rxhash);
	185
	186	/*
	187	* Returns a Tx hash based on the given packet descriptor a Tx queues' number
	188	* to be used as a distribution range.
	189	*/
	190	u16 __skb_tx_hash(const struct net_device dev, const struct sk_buff skb,
	191	unsigned int num_tx_queues)
	192	{
	193	u32 hash;
	194	u16 qoffset = 0;
	195	u16 qcount = num_tx_queues;
	196
	197	if (skb_rx_queue_recorded(skb)) {
	198	hash = skb_get_rx_queue(skb);
	199	while (unlikely(hash >= num_tx_queues))
	200	hash -= num_tx_queues;
	201	return hash;
	202	}
	203
	204	if (dev->num_tc) {
	205	u8 tc = netdev_get_prio_tc_map(dev, skb->priority);
	206	qoffset = dev->tc_to_txq[tc].offset;
	207	qcount = dev->tc_to_txq[tc].count;
	208	}
	209
	210	if (skb->sk && skb->sk->sk_hash)
	211	hash = skb->sk->sk_hash;
212	else
213	hash = (__force u16) skb->protocol;
214	hash = jhash_1word(hash, hashrnd);
215
216	return (u16) (((u64) hash * qcount) >> 32) + qoffset;
217	}
218	EXPORT_SYMBOL(__skb_tx_hash);
219
220	static inline u16 dev_cap_txqueue(struct net_device *dev, u16 queue_index)
221	{
222	if (unlikely(queue_index >= dev->real_num_tx_queues)) {
223	net_warn_ratelimited("%s selects TX queue %d, but real number of TX queues is %d\n",
224	dev->name, queue_index,
225	dev->real_num_tx_queues);
226	return 0;
227	}
228	return queue_index;
229	}
230
231	static inline int get_xps_queue(struct net_device dev, struct sk_buff skb)
232	{
233	#ifdef CONFIG_XPS
234	struct xps_dev_maps *dev_maps;
235	struct xps_map *map;
236	int queue_index = -1;
237
238	rcu_read_lock();
239	dev_maps = rcu_dereference(dev->xps_maps);
240	if (dev_maps) {
241	map = rcu_dereference(
242	dev_maps->cpu_map[raw_smp_processor_id()]);
243	if (map) {
244	if (map->len == 1)
245	queue_index = map->queues[0];
246	else {
247	u32 hash;
248	if (skb->sk && skb->sk->sk_hash)
249	hash = skb->sk->sk_hash;
250	else
251	hash = (__force u16) skb->protocol ^
252	skb->rxhash;
253	hash = jhash_1word(hash, hashrnd);
254	queue_index = map->queues[
255	((u64)hash * map->len) >> 32];
256	}
257	if (unlikely(queue_index >= dev->real_num_tx_queues))
258	queue_index = -1;
259	}
260	}
261	rcu_read_unlock();
262
263	return queue_index;
264	#else
265	return -1;
266	#endif
267	}
268
269	u16 __netdev_pick_tx(struct net_device dev, struct sk_buff skb)
270	{
271	struct sock *sk = skb->sk;
272	int queue_index = sk_tx_queue_get(sk);
273
274	if (queue_index < 0 \|\| skb->ooo_okay \|\|
275	queue_index >= dev->real_num_tx_queues) {
276	int new_index = get_xps_queue(dev, skb);
277	if (new_index < 0)
278	new_index = skb_tx_hash(dev, skb);
279
280	if (queue_index != new_index && sk) {
281	struct dst_entry *dst =
282	rcu_dereference_check(sk->sk_dst_cache, 1);
283
284	if (dst && skb_dst(skb) == dst)
285	sk_tx_queue_set(sk, queue_index);
286
287	}
288
289	queue_index = new_index;
290	}
291
292	return queue_index;
293	}
294	EXPORT_SYMBOL(__netdev_pick_tx);
295
296	struct netdev_queue netdev_pick_tx(struct net_device dev,
297	struct sk_buff *skb)
298	{
299	int queue_index = 0;
300
301	if (dev->real_num_tx_queues != 1) {
302	const struct net_device_ops *ops = dev->netdev_ops;
303	if (ops->ndo_select_queue)
304	queue_index = ops->ndo_select_queue(dev, skb);
305	else
306	queue_index = __netdev_pick_tx(dev, skb);
307	queue_index = dev_cap_txqueue(dev, queue_index);
308	}
309
310	skb_set_queue_mapping(skb, queue_index);
311	return netdev_get_tx_queue(dev, queue_index);
312	}
313
314	static int __init initialize_hashrnd(void)
315	{
316	get_random_bytes(&hashrnd, sizeof(hashrnd));
317	return 0;
318	}
319
320	late_initcall_sync(initialize_hashrnd);