flow_dissector.c 36.0 KB
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#include <linux/kernel.h>
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#include <linux/skbuff.h>
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#include <linux/export.h>
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#include <linux/ip.h>
#include <linux/ipv6.h>
#include <linux/if_vlan.h>
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#include <net/dsa.h>
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#include <net/dst_metadata.h>
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#include <net/ip.h>
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#include <net/ipv6.h>
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#include <net/gre.h>
#include <net/pptp.h>
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#include <net/tipc.h>
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#include <linux/igmp.h>
#include <linux/icmp.h>
#include <linux/sctp.h>
#include <linux/dccp.h>
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#include <linux/if_tunnel.h>
#include <linux/if_pppox.h>
#include <linux/ppp_defs.h>
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#include <linux/stddef.h>
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#include <linux/if_ether.h>
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#include <linux/mpls.h>
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#include <linux/tcp.h>
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#include <net/flow_dissector.h>
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#include <scsi/fc/fc_fcoe.h>
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static void dissector_set_key(struct flow_dissector *flow_dissector,
			      enum flow_dissector_key_id key_id)
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{
	flow_dissector->used_keys |= (1 << key_id);
}

void skb_flow_dissector_init(struct flow_dissector *flow_dissector,
			     const struct flow_dissector_key *key,
			     unsigned int key_count)
{
	unsigned int i;

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

	for (i = 0; i < key_count; i++, key++) {
		/* User should make sure that every key target offset is withing
		 * boundaries of unsigned short.
		 */
		BUG_ON(key->offset > USHRT_MAX);
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		BUG_ON(dissector_uses_key(flow_dissector,
					  key->key_id));
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		dissector_set_key(flow_dissector, key->key_id);
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		flow_dissector->offset[key->key_id] = key->offset;
	}

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	/* Ensure that the dissector always includes control and basic key.
	 * That way we are able to avoid handling lack of these in fast path.
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	 */
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	BUG_ON(!dissector_uses_key(flow_dissector,
				   FLOW_DISSECTOR_KEY_CONTROL));
	BUG_ON(!dissector_uses_key(flow_dissector,
				   FLOW_DISSECTOR_KEY_BASIC));
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}
EXPORT_SYMBOL(skb_flow_dissector_init);

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/**
 * skb_flow_get_be16 - extract be16 entity
 * @skb: sk_buff to extract from
 * @poff: offset to extract at
 * @data: raw buffer pointer to the packet
 * @hlen: packet header length
 *
 * The function will try to retrieve a be32 entity at
 * offset poff
 */
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static __be16 skb_flow_get_be16(const struct sk_buff *skb, int poff,
				void *data, int hlen)
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{
	__be16 *u, _u;

	u = __skb_header_pointer(skb, poff, sizeof(_u), data, hlen, &_u);
	if (u)
		return *u;

	return 0;
}

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/**
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 * __skb_flow_get_ports - extract the upper layer ports and return them
 * @skb: sk_buff to extract the ports from
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 * @thoff: transport header offset
 * @ip_proto: protocol for which to get port offset
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 * @data: raw buffer pointer to the packet, if NULL use skb->data
 * @hlen: packet header length, if @data is NULL use skb_headlen(skb)
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 *
 * The function will try to retrieve the ports at offset thoff + poff where poff
 * is the protocol port offset returned from proto_ports_offset
 */
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__be32 __skb_flow_get_ports(const struct sk_buff *skb, int thoff, u8 ip_proto,
			    void *data, int hlen)
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{
	int poff = proto_ports_offset(ip_proto);

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	if (!data) {
		data = skb->data;
		hlen = skb_headlen(skb);
	}

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

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

	return 0;
}
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EXPORT_SYMBOL(__skb_flow_get_ports);
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static void
skb_flow_dissect_set_enc_addr_type(enum flow_dissector_key_id type,
				   struct flow_dissector *flow_dissector,
				   void *target_container)
{
	struct flow_dissector_key_control *ctrl;

	if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_CONTROL))
		return;

	ctrl = skb_flow_dissector_target(flow_dissector,
					 FLOW_DISSECTOR_KEY_ENC_CONTROL,
					 target_container);
	ctrl->addr_type = type;
}

static void
__skb_flow_dissect_tunnel_info(const struct sk_buff *skb,
			       struct flow_dissector *flow_dissector,
			       void *target_container)
{
	struct ip_tunnel_info *info;
	struct ip_tunnel_key *key;

	/* A quick check to see if there might be something to do. */
	if (!dissector_uses_key(flow_dissector,
				FLOW_DISSECTOR_KEY_ENC_KEYID) &&
	    !dissector_uses_key(flow_dissector,
				FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS) &&
	    !dissector_uses_key(flow_dissector,
				FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS) &&
	    !dissector_uses_key(flow_dissector,
				FLOW_DISSECTOR_KEY_ENC_CONTROL) &&
	    !dissector_uses_key(flow_dissector,
				FLOW_DISSECTOR_KEY_ENC_PORTS))
		return;

	info = skb_tunnel_info(skb);
	if (!info)
		return;

	key = &info->key;

	switch (ip_tunnel_info_af(info)) {
	case AF_INET:
		skb_flow_dissect_set_enc_addr_type(FLOW_DISSECTOR_KEY_IPV4_ADDRS,
						   flow_dissector,
						   target_container);
		if (dissector_uses_key(flow_dissector,
				       FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS)) {
			struct flow_dissector_key_ipv4_addrs *ipv4;

			ipv4 = skb_flow_dissector_target(flow_dissector,
							 FLOW_DISSECTOR_KEY_ENC_IPV4_ADDRS,
							 target_container);
			ipv4->src = key->u.ipv4.src;
			ipv4->dst = key->u.ipv4.dst;
		}
		break;
	case AF_INET6:
		skb_flow_dissect_set_enc_addr_type(FLOW_DISSECTOR_KEY_IPV6_ADDRS,
						   flow_dissector,
						   target_container);
		if (dissector_uses_key(flow_dissector,
				       FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS)) {
			struct flow_dissector_key_ipv6_addrs *ipv6;

			ipv6 = skb_flow_dissector_target(flow_dissector,
							 FLOW_DISSECTOR_KEY_ENC_IPV6_ADDRS,
							 target_container);
			ipv6->src = key->u.ipv6.src;
			ipv6->dst = key->u.ipv6.dst;
		}
		break;
	}

	if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_KEYID)) {
		struct flow_dissector_key_keyid *keyid;

		keyid = skb_flow_dissector_target(flow_dissector,
						  FLOW_DISSECTOR_KEY_ENC_KEYID,
						  target_container);
		keyid->keyid = tunnel_id_to_key32(key->tun_id);
	}

	if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ENC_PORTS)) {
		struct flow_dissector_key_ports *tp;

		tp = skb_flow_dissector_target(flow_dissector,
					       FLOW_DISSECTOR_KEY_ENC_PORTS,
					       target_container);
		tp->src = key->tp_src;
		tp->dst = key->tp_dst;
	}
}

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static enum flow_dissect_ret
__skb_flow_dissect_mpls(const struct sk_buff *skb,
			struct flow_dissector *flow_dissector,
			void *target_container, void *data, int nhoff, int hlen)
{
	struct flow_dissector_key_keyid *key_keyid;
	struct mpls_label *hdr, _hdr[2];
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	u32 entry, label;
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	if (!dissector_uses_key(flow_dissector,
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				FLOW_DISSECTOR_KEY_MPLS_ENTROPY) &&
	    !dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_MPLS))
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		return FLOW_DISSECT_RET_OUT_GOOD;

	hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data,
				   hlen, &_hdr);
	if (!hdr)
		return FLOW_DISSECT_RET_OUT_BAD;

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	entry = ntohl(hdr[0].entry);
	label = (entry & MPLS_LS_LABEL_MASK) >> MPLS_LS_LABEL_SHIFT;

	if (dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_MPLS)) {
		struct flow_dissector_key_mpls *key_mpls;

		key_mpls = skb_flow_dissector_target(flow_dissector,
						     FLOW_DISSECTOR_KEY_MPLS,
						     target_container);
		key_mpls->mpls_label = label;
		key_mpls->mpls_ttl = (entry & MPLS_LS_TTL_MASK)
					>> MPLS_LS_TTL_SHIFT;
		key_mpls->mpls_tc = (entry & MPLS_LS_TC_MASK)
					>> MPLS_LS_TC_SHIFT;
		key_mpls->mpls_bos = (entry & MPLS_LS_S_MASK)
					>> MPLS_LS_S_SHIFT;
	}

	if (label == MPLS_LABEL_ENTROPY) {
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		key_keyid = skb_flow_dissector_target(flow_dissector,
						      FLOW_DISSECTOR_KEY_MPLS_ENTROPY,
						      target_container);
		key_keyid->keyid = hdr[1].entry & htonl(MPLS_LS_LABEL_MASK);
	}
	return FLOW_DISSECT_RET_OUT_GOOD;
}

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static enum flow_dissect_ret
__skb_flow_dissect_arp(const struct sk_buff *skb,
		       struct flow_dissector *flow_dissector,
		       void *target_container, void *data, int nhoff, int hlen)
{
	struct flow_dissector_key_arp *key_arp;
	struct {
		unsigned char ar_sha[ETH_ALEN];
		unsigned char ar_sip[4];
		unsigned char ar_tha[ETH_ALEN];
		unsigned char ar_tip[4];
	} *arp_eth, _arp_eth;
	const struct arphdr *arp;
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	struct arphdr _arp;
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	if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_ARP))
		return FLOW_DISSECT_RET_OUT_GOOD;

	arp = __skb_header_pointer(skb, nhoff, sizeof(_arp), data,
				   hlen, &_arp);
	if (!arp)
		return FLOW_DISSECT_RET_OUT_BAD;

	if (arp->ar_hrd != htons(ARPHRD_ETHER) ||
	    arp->ar_pro != htons(ETH_P_IP) ||
	    arp->ar_hln != ETH_ALEN ||
	    arp->ar_pln != 4 ||
	    (arp->ar_op != htons(ARPOP_REPLY) &&
	     arp->ar_op != htons(ARPOP_REQUEST)))
		return FLOW_DISSECT_RET_OUT_BAD;

	arp_eth = __skb_header_pointer(skb, nhoff + sizeof(_arp),
				       sizeof(_arp_eth), data,
				       hlen, &_arp_eth);
	if (!arp_eth)
		return FLOW_DISSECT_RET_OUT_BAD;

	key_arp = skb_flow_dissector_target(flow_dissector,
					    FLOW_DISSECTOR_KEY_ARP,
					    target_container);

	memcpy(&key_arp->sip, arp_eth->ar_sip, sizeof(key_arp->sip));
	memcpy(&key_arp->tip, arp_eth->ar_tip, sizeof(key_arp->tip));

	/* Only store the lower byte of the opcode;
	 * this covers ARPOP_REPLY and ARPOP_REQUEST.
	 */
	key_arp->op = ntohs(arp->ar_op) & 0xff;

	ether_addr_copy(key_arp->sha, arp_eth->ar_sha);
	ether_addr_copy(key_arp->tha, arp_eth->ar_tha);

	return FLOW_DISSECT_RET_OUT_GOOD;
}

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static enum flow_dissect_ret
__skb_flow_dissect_gre(const struct sk_buff *skb,
		       struct flow_dissector_key_control *key_control,
		       struct flow_dissector *flow_dissector,
		       void *target_container, void *data,
		       __be16 *p_proto, int *p_nhoff, int *p_hlen,
		       unsigned int flags)
{
	struct flow_dissector_key_keyid *key_keyid;
	struct gre_base_hdr *hdr, _hdr;
	int offset = 0;
	u16 gre_ver;

	hdr = __skb_header_pointer(skb, *p_nhoff, sizeof(_hdr),
				   data, *p_hlen, &_hdr);
	if (!hdr)
		return FLOW_DISSECT_RET_OUT_BAD;

	/* Only look inside GRE without routing */
	if (hdr->flags & GRE_ROUTING)
		return FLOW_DISSECT_RET_OUT_GOOD;

	/* Only look inside GRE for version 0 and 1 */
	gre_ver = ntohs(hdr->flags & GRE_VERSION);
	if (gre_ver > 1)
		return FLOW_DISSECT_RET_OUT_GOOD;

	*p_proto = hdr->protocol;
	if (gre_ver) {
		/* Version1 must be PPTP, and check the flags */
		if (!(*p_proto == GRE_PROTO_PPP && (hdr->flags & GRE_KEY)))
			return FLOW_DISSECT_RET_OUT_GOOD;
	}

	offset += sizeof(struct gre_base_hdr);

	if (hdr->flags & GRE_CSUM)
		offset += sizeof(((struct gre_full_hdr *) 0)->csum) +
			  sizeof(((struct gre_full_hdr *) 0)->reserved1);

	if (hdr->flags & GRE_KEY) {
		const __be32 *keyid;
		__be32 _keyid;

		keyid = __skb_header_pointer(skb, *p_nhoff + offset,
					     sizeof(_keyid),
					     data, *p_hlen, &_keyid);
		if (!keyid)
			return FLOW_DISSECT_RET_OUT_BAD;

		if (dissector_uses_key(flow_dissector,
				       FLOW_DISSECTOR_KEY_GRE_KEYID)) {
			key_keyid = skb_flow_dissector_target(flow_dissector,
							      FLOW_DISSECTOR_KEY_GRE_KEYID,
							      target_container);
			if (gre_ver == 0)
				key_keyid->keyid = *keyid;
			else
				key_keyid->keyid = *keyid & GRE_PPTP_KEY_MASK;
		}
		offset += sizeof(((struct gre_full_hdr *) 0)->key);
	}

	if (hdr->flags & GRE_SEQ)
		offset += sizeof(((struct pptp_gre_header *) 0)->seq);

	if (gre_ver == 0) {
		if (*p_proto == htons(ETH_P_TEB)) {
			const struct ethhdr *eth;
			struct ethhdr _eth;

			eth = __skb_header_pointer(skb, *p_nhoff + offset,
						   sizeof(_eth),
						   data, *p_hlen, &_eth);
			if (!eth)
				return FLOW_DISSECT_RET_OUT_BAD;
			*p_proto = eth->h_proto;
			offset += sizeof(*eth);

			/* Cap headers that we access via pointers at the
			 * end of the Ethernet header as our maximum alignment
			 * at that point is only 2 bytes.
			 */
			if (NET_IP_ALIGN)
				*p_hlen = *p_nhoff + offset;
		}
	} else { /* version 1, must be PPTP */
		u8 _ppp_hdr[PPP_HDRLEN];
		u8 *ppp_hdr;

		if (hdr->flags & GRE_ACK)
			offset += sizeof(((struct pptp_gre_header *) 0)->ack);

		ppp_hdr = __skb_header_pointer(skb, *p_nhoff + offset,
					       sizeof(_ppp_hdr),
					       data, *p_hlen, _ppp_hdr);
		if (!ppp_hdr)
			return FLOW_DISSECT_RET_OUT_BAD;

		switch (PPP_PROTOCOL(ppp_hdr)) {
		case PPP_IP:
			*p_proto = htons(ETH_P_IP);
			break;
		case PPP_IPV6:
			*p_proto = htons(ETH_P_IPV6);
			break;
		default:
			/* Could probably catch some more like MPLS */
			break;
		}

		offset += PPP_HDRLEN;
	}

	*p_nhoff += offset;
	key_control->flags |= FLOW_DIS_ENCAPSULATION;
	if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP)
		return FLOW_DISSECT_RET_OUT_GOOD;

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	return FLOW_DISSECT_RET_PROTO_AGAIN;
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}

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static void
__skb_flow_dissect_tcp(const struct sk_buff *skb,
		       struct flow_dissector *flow_dissector,
		       void *target_container, void *data, int thoff, int hlen)
{
	struct flow_dissector_key_tcp *key_tcp;
	struct tcphdr *th, _th;

	if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_TCP))
		return;

	th = __skb_header_pointer(skb, thoff, sizeof(_th), data, hlen, &_th);
	if (!th)
		return;

	if (unlikely(__tcp_hdrlen(th) < sizeof(_th)))
		return;

	key_tcp = skb_flow_dissector_target(flow_dissector,
					    FLOW_DISSECTOR_KEY_TCP,
					    target_container);
	key_tcp->flags = (*(__be16 *) &tcp_flag_word(th) & htons(0x0FFF));
}

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static void
__skb_flow_dissect_ipv4(const struct sk_buff *skb,
			struct flow_dissector *flow_dissector,
			void *target_container, void *data, const struct iphdr *iph)
{
	struct flow_dissector_key_ip *key_ip;

	if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IP))
		return;

	key_ip = skb_flow_dissector_target(flow_dissector,
					   FLOW_DISSECTOR_KEY_IP,
					   target_container);
	key_ip->tos = iph->tos;
	key_ip->ttl = iph->ttl;
}

static void
__skb_flow_dissect_ipv6(const struct sk_buff *skb,
			struct flow_dissector *flow_dissector,
			void *target_container, void *data, const struct ipv6hdr *iph)
{
	struct flow_dissector_key_ip *key_ip;

	if (!dissector_uses_key(flow_dissector, FLOW_DISSECTOR_KEY_IP))
		return;

	key_ip = skb_flow_dissector_target(flow_dissector,
					   FLOW_DISSECTOR_KEY_IP,
					   target_container);
	key_ip->tos = ipv6_get_dsfield(iph);
	key_ip->ttl = iph->hop_limit;
}

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/* Maximum number of protocol headers that can be parsed in
 * __skb_flow_dissect
 */
#define MAX_FLOW_DISSECT_HDRS	15

static bool skb_flow_dissect_allowed(int *num_hdrs)
{
	++*num_hdrs;

	return (*num_hdrs <= MAX_FLOW_DISSECT_HDRS);
}

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/**
 * __skb_flow_dissect - extract the flow_keys struct and return it
 * @skb: sk_buff to extract the flow from, can be NULL if the rest are specified
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 * @flow_dissector: list of keys to dissect
 * @target_container: target structure to put dissected values into
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 * @data: raw buffer pointer to the packet, if NULL use skb->data
 * @proto: protocol for which to get the flow, if @data is NULL use skb->protocol
 * @nhoff: network header offset, if @data is NULL use skb_network_offset(skb)
 * @hlen: packet header length, if @data is NULL use skb_headlen(skb)
 *
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 * The function will try to retrieve individual keys into target specified
 * by flow_dissector from either the skbuff or a raw buffer specified by the
 * rest parameters.
 *
 * Caller must take care of zeroing target container memory.
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 */
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bool __skb_flow_dissect(const struct sk_buff *skb,
			struct flow_dissector *flow_dissector,
			void *target_container,
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			void *data, __be16 proto, int nhoff, int hlen,
			unsigned int flags)
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{
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	struct flow_dissector_key_control *key_control;
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	struct flow_dissector_key_basic *key_basic;
	struct flow_dissector_key_addrs *key_addrs;
	struct flow_dissector_key_ports *key_ports;
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	struct flow_dissector_key_icmp *key_icmp;
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	struct flow_dissector_key_tags *key_tags;
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	struct flow_dissector_key_vlan *key_vlan;
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	enum flow_dissect_ret fdret;
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	bool skip_vlan = false;
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	int num_hdrs = 0;
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	u8 ip_proto = 0;
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	bool ret;
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	if (!data) {
		data = skb->data;
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		proto = skb_vlan_tag_present(skb) ?
			 skb->vlan_proto : skb->protocol;
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		nhoff = skb_network_offset(skb);
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		hlen = skb_headlen(skb);
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#if IS_ENABLED(CONFIG_NET_DSA)
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		if (unlikely(skb->dev && netdev_uses_dsa(skb->dev))) {
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			const struct dsa_device_ops *ops;
			int offset;

			ops = skb->dev->dsa_ptr->tag_ops;
			if (ops->flow_dissect &&
			    !ops->flow_dissect(skb, &proto, &offset)) {
				hlen -= offset;
				nhoff += offset;
			}
		}
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#endif
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	}

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	/* It is ensured by skb_flow_dissector_init() that control key will
	 * be always present.
	 */
	key_control = skb_flow_dissector_target(flow_dissector,
						FLOW_DISSECTOR_KEY_CONTROL,
						target_container);

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	/* It is ensured by skb_flow_dissector_init() that basic key will
	 * be always present.
	 */
	key_basic = skb_flow_dissector_target(flow_dissector,
					      FLOW_DISSECTOR_KEY_BASIC,
					      target_container);
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	__skb_flow_dissect_tunnel_info(skb, flow_dissector,
				       target_container);

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	if (dissector_uses_key(flow_dissector,
			       FLOW_DISSECTOR_KEY_ETH_ADDRS)) {
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		struct ethhdr *eth = eth_hdr(skb);
		struct flow_dissector_key_eth_addrs *key_eth_addrs;

		key_eth_addrs = skb_flow_dissector_target(flow_dissector,
							  FLOW_DISSECTOR_KEY_ETH_ADDRS,
							  target_container);
		memcpy(key_eth_addrs, &eth->h_dest, sizeof(*key_eth_addrs));
	}

593
proto_again:
594 595
	fdret = FLOW_DISSECT_RET_CONTINUE;

E
Eric Dumazet 已提交
596
	switch (proto) {
597
	case htons(ETH_P_IP): {
E
Eric Dumazet 已提交
598 599
		const struct iphdr *iph;
		struct iphdr _iph;
600

601
		iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph);
602 603 604 605 606
		if (!iph || iph->ihl < 5) {
			fdret = FLOW_DISSECT_RET_OUT_BAD;
			break;
		}

607
		nhoff += iph->ihl * 4;
E
Eric Dumazet 已提交
608

609 610
		ip_proto = iph->protocol;

611 612 613 614 615 616 617 618 619 620
		if (dissector_uses_key(flow_dissector,
				       FLOW_DISSECTOR_KEY_IPV4_ADDRS)) {
			key_addrs = skb_flow_dissector_target(flow_dissector,
							      FLOW_DISSECTOR_KEY_IPV4_ADDRS,
							      target_container);

			memcpy(&key_addrs->v4addrs, &iph->saddr,
			       sizeof(key_addrs->v4addrs));
			key_control->addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
		}
621 622

		if (ip_is_fragment(iph)) {
623
			key_control->flags |= FLOW_DIS_IS_FRAGMENT;
624 625

			if (iph->frag_off & htons(IP_OFFSET)) {
626 627
				fdret = FLOW_DISSECT_RET_OUT_GOOD;
				break;
628
			} else {
629
				key_control->flags |= FLOW_DIS_FIRST_FRAG;
630 631 632 633 634
				if (!(flags &
				      FLOW_DISSECTOR_F_PARSE_1ST_FRAG)) {
					fdret = FLOW_DISSECT_RET_OUT_GOOD;
					break;
				}
635 636 637
			}
		}

638 639 640
		__skb_flow_dissect_ipv4(skb, flow_dissector,
					target_container, data, iph);

641 642 643 644
		if (flags & FLOW_DISSECTOR_F_STOP_AT_L3) {
			fdret = FLOW_DISSECT_RET_OUT_GOOD;
			break;
		}
645

E
Eric Dumazet 已提交
646 647
		break;
	}
648
	case htons(ETH_P_IPV6): {
E
Eric Dumazet 已提交
649 650
		const struct ipv6hdr *iph;
		struct ipv6hdr _iph;
651

652
		iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph);
653 654 655 656
		if (!iph) {
			fdret = FLOW_DISSECT_RET_OUT_BAD;
			break;
		}
E
Eric Dumazet 已提交
657 658 659

		ip_proto = iph->nexthdr;
		nhoff += sizeof(struct ipv6hdr);
660

661 662
		if (dissector_uses_key(flow_dissector,
				       FLOW_DISSECTOR_KEY_IPV6_ADDRS)) {
663 664 665
			key_addrs = skb_flow_dissector_target(flow_dissector,
							      FLOW_DISSECTOR_KEY_IPV6_ADDRS,
							      target_container);
666

667 668
			memcpy(&key_addrs->v6addrs, &iph->saddr,
			       sizeof(key_addrs->v6addrs));
669
			key_control->addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
670
		}
671

672 673 674 675 676 677
		if ((dissector_uses_key(flow_dissector,
					FLOW_DISSECTOR_KEY_FLOW_LABEL) ||
		     (flags & FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL)) &&
		    ip6_flowlabel(iph)) {
			__be32 flow_label = ip6_flowlabel(iph);

678 679
			if (dissector_uses_key(flow_dissector,
					       FLOW_DISSECTOR_KEY_FLOW_LABEL)) {
680 681 682 683
				key_tags = skb_flow_dissector_target(flow_dissector,
								     FLOW_DISSECTOR_KEY_FLOW_LABEL,
								     target_container);
				key_tags->flow_label = ntohl(flow_label);
684
			}
685 686 687 688
			if (flags & FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL) {
				fdret = FLOW_DISSECT_RET_OUT_GOOD;
				break;
			}
689 690
		}

691 692 693
		__skb_flow_dissect_ipv6(skb, flow_dissector,
					target_container, data, iph);

694
		if (flags & FLOW_DISSECTOR_F_STOP_AT_L3)
695
			fdret = FLOW_DISSECT_RET_OUT_GOOD;
696

E
Eric Dumazet 已提交
697 698
		break;
	}
699 700
	case htons(ETH_P_8021AD):
	case htons(ETH_P_8021Q): {
E
Eric Dumazet 已提交
701
		const struct vlan_hdr *vlan;
702 703
		struct vlan_hdr _vlan;
		bool vlan_tag_present = skb && skb_vlan_tag_present(skb);
E
Eric Dumazet 已提交
704

705
		if (vlan_tag_present)
706 707
			proto = skb->protocol;

708
		if (!vlan_tag_present || eth_type_vlan(skb->protocol)) {
709 710
			vlan = __skb_header_pointer(skb, nhoff, sizeof(_vlan),
						    data, hlen, &_vlan);
711 712 713 714 715
			if (!vlan) {
				fdret = FLOW_DISSECT_RET_OUT_BAD;
				break;
			}

716 717
			proto = vlan->h_vlan_encapsulated_proto;
			nhoff += sizeof(*vlan);
718 719 720 721
			if (skip_vlan) {
				fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
				break;
			}
722
		}
E
Eric Dumazet 已提交
723

724
		skip_vlan = true;
725
		if (dissector_uses_key(flow_dissector,
726 727 728
				       FLOW_DISSECTOR_KEY_VLAN)) {
			key_vlan = skb_flow_dissector_target(flow_dissector,
							     FLOW_DISSECTOR_KEY_VLAN,
T
Tom Herbert 已提交
729 730
							     target_container);

731
			if (vlan_tag_present) {
732 733 734 735 736
				key_vlan->vlan_id = skb_vlan_tag_get_id(skb);
				key_vlan->vlan_priority =
					(skb_vlan_tag_get_prio(skb) >> VLAN_PRIO_SHIFT);
			} else {
				key_vlan->vlan_id = ntohs(vlan->h_vlan_TCI) &
737
					VLAN_VID_MASK;
738 739 740 741
				key_vlan->vlan_priority =
					(ntohs(vlan->h_vlan_TCI) &
					 VLAN_PRIO_MASK) >> VLAN_PRIO_SHIFT;
			}
T
Tom Herbert 已提交
742 743
		}

744 745
		fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
		break;
E
Eric Dumazet 已提交
746
	}
747
	case htons(ETH_P_PPP_SES): {
E
Eric Dumazet 已提交
748 749 750 751
		struct {
			struct pppoe_hdr hdr;
			__be16 proto;
		} *hdr, _hdr;
752
		hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
753 754 755 756 757
		if (!hdr) {
			fdret = FLOW_DISSECT_RET_OUT_BAD;
			break;
		}

E
Eric Dumazet 已提交
758 759 760
		proto = hdr->proto;
		nhoff += PPPOE_SES_HLEN;
		switch (proto) {
761
		case htons(PPP_IP):
762 763 764
			proto = htons(ETH_P_IP);
			fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
			break;
765
		case htons(PPP_IPV6):
766 767 768
			proto = htons(ETH_P_IPV6);
			fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
			break;
E
Eric Dumazet 已提交
769
		default:
770 771
			fdret = FLOW_DISSECT_RET_OUT_BAD;
			break;
E
Eric Dumazet 已提交
772
		}
773
		break;
E
Eric Dumazet 已提交
774
	}
E
Erik Hugne 已提交
775
	case htons(ETH_P_TIPC): {
776 777 778 779
		struct tipc_basic_hdr *hdr, _hdr;

		hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr),
					   data, hlen, &_hdr);
780 781 782 783
		if (!hdr) {
			fdret = FLOW_DISSECT_RET_OUT_BAD;
			break;
		}
784

785
		if (dissector_uses_key(flow_dissector,
786
				       FLOW_DISSECTOR_KEY_TIPC)) {
787
			key_addrs = skb_flow_dissector_target(flow_dissector,
788
							      FLOW_DISSECTOR_KEY_TIPC,
789
							      target_container);
790 791
			key_addrs->tipckey.key = tipc_hdr_rps_key(hdr);
			key_control->addr_type = FLOW_DISSECTOR_KEY_TIPC;
792
		}
793 794
		fdret = FLOW_DISSECT_RET_OUT_GOOD;
		break;
E
Erik Hugne 已提交
795
	}
796 797

	case htons(ETH_P_MPLS_UC):
798
	case htons(ETH_P_MPLS_MC):
799
		fdret = __skb_flow_dissect_mpls(skb, flow_dissector,
800
						target_container, data,
801 802
						nhoff, hlen);
		break;
803
	case htons(ETH_P_FCOE):
804 805 806 807
		if ((hlen - nhoff) < FCOE_HEADER_LEN) {
			fdret = FLOW_DISSECT_RET_OUT_BAD;
			break;
		}
808 809

		nhoff += FCOE_HEADER_LEN;
810 811
		fdret = FLOW_DISSECT_RET_OUT_GOOD;
		break;
S
Simon Horman 已提交
812 813

	case htons(ETH_P_ARP):
814
	case htons(ETH_P_RARP):
815
		fdret = __skb_flow_dissect_arp(skb, flow_dissector,
816
					       target_container, data,
817 818 819 820 821 822 823 824 825 826 827 828 829
					       nhoff, hlen);
		break;

	default:
		fdret = FLOW_DISSECT_RET_OUT_BAD;
		break;
	}

	/* Process result of proto processing */
	switch (fdret) {
	case FLOW_DISSECT_RET_OUT_GOOD:
		goto out_good;
	case FLOW_DISSECT_RET_PROTO_AGAIN:
830 831 832
		if (skb_flow_dissect_allowed(&num_hdrs))
			goto proto_again;
		goto out_good;
833 834 835 836
	case FLOW_DISSECT_RET_CONTINUE:
	case FLOW_DISSECT_RET_IPPROTO_AGAIN:
		break;
	case FLOW_DISSECT_RET_OUT_BAD:
E
Eric Dumazet 已提交
837
	default:
838
		goto out_bad;
E
Eric Dumazet 已提交
839 840
	}

841
ip_proto_again:
842 843
	fdret = FLOW_DISSECT_RET_CONTINUE;

E
Eric Dumazet 已提交
844
	switch (ip_proto) {
845
	case IPPROTO_GRE:
846
		fdret = __skb_flow_dissect_gre(skb, key_control, flow_dissector,
847
					       target_container, data,
848 849 850
					       &proto, &nhoff, &hlen, flags);
		break;

851 852 853 854 855 856 857 858 859 860
	case NEXTHDR_HOP:
	case NEXTHDR_ROUTING:
	case NEXTHDR_DEST: {
		u8 _opthdr[2], *opthdr;

		if (proto != htons(ETH_P_IPV6))
			break;

		opthdr = __skb_header_pointer(skb, nhoff, sizeof(_opthdr),
					      data, hlen, &_opthdr);
861 862 863 864
		if (!opthdr) {
			fdret = FLOW_DISSECT_RET_OUT_BAD;
			break;
		}
865

866 867
		ip_proto = opthdr[0];
		nhoff += (opthdr[1] + 1) << 3;
868

869 870
		fdret = FLOW_DISSECT_RET_IPPROTO_AGAIN;
		break;
871
	}
872 873 874 875 876 877 878 879 880
	case NEXTHDR_FRAGMENT: {
		struct frag_hdr _fh, *fh;

		if (proto != htons(ETH_P_IPV6))
			break;

		fh = __skb_header_pointer(skb, nhoff, sizeof(_fh),
					  data, hlen, &_fh);

881 882 883 884
		if (!fh) {
			fdret = FLOW_DISSECT_RET_OUT_BAD;
			break;
		}
885

886
		key_control->flags |= FLOW_DIS_IS_FRAGMENT;
887 888

		nhoff += sizeof(_fh);
889
		ip_proto = fh->nexthdr;
890 891

		if (!(fh->frag_off & htons(IP6_OFFSET))) {
892
			key_control->flags |= FLOW_DIS_FIRST_FRAG;
893 894 895 896
			if (flags & FLOW_DISSECTOR_F_PARSE_1ST_FRAG) {
				fdret = FLOW_DISSECT_RET_IPPROTO_AGAIN;
				break;
			}
897
		}
898 899 900

		fdret = FLOW_DISSECT_RET_OUT_GOOD;
		break;
901
	}
E
Eric Dumazet 已提交
902
	case IPPROTO_IPIP:
T
Tom Herbert 已提交
903
		proto = htons(ETH_P_IP);
904

905
		key_control->flags |= FLOW_DIS_ENCAPSULATION;
906 907 908 909 910 911 912
		if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP) {
			fdret = FLOW_DISSECT_RET_OUT_GOOD;
			break;
		}

		fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
		break;
913

914 915
	case IPPROTO_IPV6:
		proto = htons(ETH_P_IPV6);
916

917
		key_control->flags |= FLOW_DIS_ENCAPSULATION;
918 919 920 921 922 923 924 925
		if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP) {
			fdret = FLOW_DISSECT_RET_OUT_GOOD;
			break;
		}

		fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
		break;

926

927 928
	case IPPROTO_MPLS:
		proto = htons(ETH_P_MPLS_UC);
929 930 931
		fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
		break;

932 933 934 935
	case IPPROTO_TCP:
		__skb_flow_dissect_tcp(skb, flow_dissector, target_container,
				       data, nhoff, hlen);
		break;
936

E
Eric Dumazet 已提交
937 938 939 940
	default:
		break;
	}

941 942
	if (dissector_uses_key(flow_dissector,
			       FLOW_DISSECTOR_KEY_PORTS)) {
943 944 945 946 947 948
		key_ports = skb_flow_dissector_target(flow_dissector,
						      FLOW_DISSECTOR_KEY_PORTS,
						      target_container);
		key_ports->ports = __skb_flow_get_ports(skb, nhoff, ip_proto,
							data, hlen);
	}
949

S
Simon Horman 已提交
950 951 952 953 954 955 956 957
	if (dissector_uses_key(flow_dissector,
			       FLOW_DISSECTOR_KEY_ICMP)) {
		key_icmp = skb_flow_dissector_target(flow_dissector,
						     FLOW_DISSECTOR_KEY_ICMP,
						     target_container);
		key_icmp->icmp = skb_flow_get_be16(skb, nhoff, data, hlen);
	}

958 959 960
	/* Process result of IP proto processing */
	switch (fdret) {
	case FLOW_DISSECT_RET_PROTO_AGAIN:
961 962 963
		if (skb_flow_dissect_allowed(&num_hdrs))
			goto proto_again;
		break;
964
	case FLOW_DISSECT_RET_IPPROTO_AGAIN:
965 966 967
		if (skb_flow_dissect_allowed(&num_hdrs))
			goto ip_proto_again;
		break;
968 969 970 971 972 973 974 975
	case FLOW_DISSECT_RET_OUT_GOOD:
	case FLOW_DISSECT_RET_CONTINUE:
		break;
	case FLOW_DISSECT_RET_OUT_BAD:
	default:
		goto out_bad;
	}

976 977 978
out_good:
	ret = true;

979 980
	key_control->thoff = (u16)nhoff;
out:
981 982 983 984
	key_basic->n_proto = proto;
	key_basic->ip_proto = ip_proto;

	return ret;
985 986 987 988 989

out_bad:
	ret = false;
	key_control->thoff = min_t(u16, nhoff, skb ? skb->len : hlen);
	goto out;
E
Eric Dumazet 已提交
990
}
991
EXPORT_SYMBOL(__skb_flow_dissect);
992 993

static u32 hashrnd __read_mostly;
994 995 996 997 998
static __always_inline void __flow_hash_secret_init(void)
{
	net_get_random_once(&hashrnd, sizeof(hashrnd));
}

999 1000
static __always_inline u32 __flow_hash_words(const u32 *words, u32 length,
					     u32 keyval)
1001 1002 1003 1004
{
	return jhash2(words, length, keyval);
}

1005
static inline const u32 *flow_keys_hash_start(const struct flow_keys *flow)
1006
{
1007 1008
	const void *p = flow;

1009
	BUILD_BUG_ON(FLOW_KEYS_HASH_OFFSET % sizeof(u32));
1010
	return (const u32 *)(p + FLOW_KEYS_HASH_OFFSET);
1011 1012
}

1013
static inline size_t flow_keys_hash_length(const struct flow_keys *flow)
1014
{
1015
	size_t diff = FLOW_KEYS_HASH_OFFSET + sizeof(flow->addrs);
1016
	BUILD_BUG_ON((sizeof(*flow) - FLOW_KEYS_HASH_OFFSET) % sizeof(u32));
1017 1018 1019 1020 1021 1022 1023 1024 1025 1026
	BUILD_BUG_ON(offsetof(typeof(*flow), addrs) !=
		     sizeof(*flow) - sizeof(flow->addrs));

	switch (flow->control.addr_type) {
	case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
		diff -= sizeof(flow->addrs.v4addrs);
		break;
	case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
		diff -= sizeof(flow->addrs.v6addrs);
		break;
1027 1028
	case FLOW_DISSECTOR_KEY_TIPC:
		diff -= sizeof(flow->addrs.tipckey);
T
Tom Herbert 已提交
1029
		break;
1030 1031 1032 1033 1034 1035 1036 1037 1038 1039 1040 1041
	}
	return (sizeof(*flow) - diff) / sizeof(u32);
}

__be32 flow_get_u32_src(const struct flow_keys *flow)
{
	switch (flow->control.addr_type) {
	case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
		return flow->addrs.v4addrs.src;
	case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
		return (__force __be32)ipv6_addr_hash(
			&flow->addrs.v6addrs.src);
1042 1043
	case FLOW_DISSECTOR_KEY_TIPC:
		return flow->addrs.tipckey.key;
1044 1045 1046 1047 1048 1049 1050 1051 1052 1053 1054 1055 1056 1057 1058 1059 1060 1061 1062 1063 1064 1065 1066 1067 1068 1069 1070 1071 1072 1073 1074 1075 1076 1077 1078 1079 1080 1081 1082 1083 1084 1085 1086 1087 1088 1089 1090 1091 1092 1093 1094
	default:
		return 0;
	}
}
EXPORT_SYMBOL(flow_get_u32_src);

__be32 flow_get_u32_dst(const struct flow_keys *flow)
{
	switch (flow->control.addr_type) {
	case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
		return flow->addrs.v4addrs.dst;
	case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
		return (__force __be32)ipv6_addr_hash(
			&flow->addrs.v6addrs.dst);
	default:
		return 0;
	}
}
EXPORT_SYMBOL(flow_get_u32_dst);

static inline void __flow_hash_consistentify(struct flow_keys *keys)
{
	int addr_diff, i;

	switch (keys->control.addr_type) {
	case FLOW_DISSECTOR_KEY_IPV4_ADDRS:
		addr_diff = (__force u32)keys->addrs.v4addrs.dst -
			    (__force u32)keys->addrs.v4addrs.src;
		if ((addr_diff < 0) ||
		    (addr_diff == 0 &&
		     ((__force u16)keys->ports.dst <
		      (__force u16)keys->ports.src))) {
			swap(keys->addrs.v4addrs.src, keys->addrs.v4addrs.dst);
			swap(keys->ports.src, keys->ports.dst);
		}
		break;
	case FLOW_DISSECTOR_KEY_IPV6_ADDRS:
		addr_diff = memcmp(&keys->addrs.v6addrs.dst,
				   &keys->addrs.v6addrs.src,
				   sizeof(keys->addrs.v6addrs.dst));
		if ((addr_diff < 0) ||
		    (addr_diff == 0 &&
		     ((__force u16)keys->ports.dst <
		      (__force u16)keys->ports.src))) {
			for (i = 0; i < 4; i++)
				swap(keys->addrs.v6addrs.src.s6_addr32[i],
				     keys->addrs.v6addrs.dst.s6_addr32[i]);
			swap(keys->ports.src, keys->ports.dst);
		}
		break;
	}
1095 1096
}

T
Tom Herbert 已提交
1097
static inline u32 __flow_hash_from_keys(struct flow_keys *keys, u32 keyval)
1098 1099 1100
{
	u32 hash;

1101
	__flow_hash_consistentify(keys);
1102

1103
	hash = __flow_hash_words(flow_keys_hash_start(keys),
1104
				 flow_keys_hash_length(keys), keyval);
1105 1106 1107 1108 1109 1110 1111 1112
	if (!hash)
		hash = 1;

	return hash;
}

u32 flow_hash_from_keys(struct flow_keys *keys)
{
T
Tom Herbert 已提交
1113 1114
	__flow_hash_secret_init();
	return __flow_hash_from_keys(keys, hashrnd);
1115 1116 1117
}
EXPORT_SYMBOL(flow_hash_from_keys);

T
Tom Herbert 已提交
1118 1119 1120
static inline u32 ___skb_get_hash(const struct sk_buff *skb,
				  struct flow_keys *keys, u32 keyval)
{
1121 1122
	skb_flow_dissect_flow_keys(skb, keys,
				   FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL);
T
Tom Herbert 已提交
1123 1124 1125 1126

	return __flow_hash_from_keys(keys, keyval);
}

T
Tom Herbert 已提交
1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145
struct _flow_keys_digest_data {
	__be16	n_proto;
	u8	ip_proto;
	u8	padding;
	__be32	ports;
	__be32	src;
	__be32	dst;
};

void make_flow_keys_digest(struct flow_keys_digest *digest,
			   const struct flow_keys *flow)
{
	struct _flow_keys_digest_data *data =
	    (struct _flow_keys_digest_data *)digest;

	BUILD_BUG_ON(sizeof(*data) > sizeof(*digest));

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

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	data->n_proto = flow->basic.n_proto;
	data->ip_proto = flow->basic.ip_proto;
	data->ports = flow->ports.ports;
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	data->src = flow->addrs.v4addrs.src;
	data->dst = flow->addrs.v4addrs.dst;
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}
EXPORT_SYMBOL(make_flow_keys_digest);

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static struct flow_dissector flow_keys_dissector_symmetric __read_mostly;

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u32 __skb_get_hash_symmetric(const struct sk_buff *skb)
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{
	struct flow_keys keys;

	__flow_hash_secret_init();

	memset(&keys, 0, sizeof(keys));
	__skb_flow_dissect(skb, &flow_keys_dissector_symmetric, &keys,
			   NULL, 0, 0, 0,
			   FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL);

	return __flow_hash_from_keys(&keys, hashrnd);
}
EXPORT_SYMBOL_GPL(__skb_get_hash_symmetric);

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/**
 * __skb_get_hash: calculate a flow hash
 * @skb: sk_buff to calculate flow hash from
 *
 * This function calculates a flow hash based on src/dst addresses
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 * 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
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 * if hash is a canonical 4-tuple hash over transport ports.
 */
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void __skb_get_hash(struct sk_buff *skb)
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{
	struct flow_keys keys;
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	u32 hash;
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	__flow_hash_secret_init();

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	hash = ___skb_get_hash(skb, &keys, hashrnd);

	__skb_set_sw_hash(skb, hash, flow_keys_have_l4(&keys));
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}
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EXPORT_SYMBOL(__skb_get_hash);
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__u32 skb_get_hash_perturb(const struct sk_buff *skb, u32 perturb)
{
	struct flow_keys keys;

	return ___skb_get_hash(skb, &keys, perturb);
}
EXPORT_SYMBOL(skb_get_hash_perturb);

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u32 __skb_get_poff(const struct sk_buff *skb, void *data,
		   const struct flow_keys *keys, int hlen)
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{
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	u32 poff = keys->control.thoff;
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	/* skip L4 headers for fragments after the first */
	if ((keys->control.flags & FLOW_DIS_IS_FRAGMENT) &&
	    !(keys->control.flags & FLOW_DIS_FIRST_FRAG))
		return poff;

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	switch (keys->basic.ip_proto) {
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	case IPPROTO_TCP: {
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		/* access doff as u8 to avoid unaligned access */
		const u8 *doff;
		u8 _doff;
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		doff = __skb_header_pointer(skb, poff + 12, sizeof(_doff),
					    data, hlen, &_doff);
		if (!doff)
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			return poff;

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		poff += max_t(u32, sizeof(struct tcphdr), (*doff & 0xF0) >> 2);
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		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;
}

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/**
 * skb_get_poff - get the offset to the payload
 * @skb: sk_buff to get the payload offset from
 *
 * The function will get the offset to the payload as far as it could
 * be dissected.  The main user is currently BPF, so that we can dynamically
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 * 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;

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

	return __skb_get_poff(skb, skb->data, &keys, skb_headlen(skb));
}
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__u32 __get_hash_from_flowi6(const struct flowi6 *fl6, struct flow_keys *keys)
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{
	memset(keys, 0, sizeof(*keys));

	memcpy(&keys->addrs.v6addrs.src, &fl6->saddr,
	    sizeof(keys->addrs.v6addrs.src));
	memcpy(&keys->addrs.v6addrs.dst, &fl6->daddr,
	    sizeof(keys->addrs.v6addrs.dst));
	keys->control.addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
	keys->ports.src = fl6->fl6_sport;
	keys->ports.dst = fl6->fl6_dport;
	keys->keyid.keyid = fl6->fl6_gre_key;
	keys->tags.flow_label = (__force u32)fl6->flowlabel;
	keys->basic.ip_proto = fl6->flowi6_proto;

	return flow_hash_from_keys(keys);
}
EXPORT_SYMBOL(__get_hash_from_flowi6);

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__u32 __get_hash_from_flowi4(const struct flowi4 *fl4, struct flow_keys *keys)
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{
	memset(keys, 0, sizeof(*keys));

	keys->addrs.v4addrs.src = fl4->saddr;
	keys->addrs.v4addrs.dst = fl4->daddr;
	keys->control.addr_type = FLOW_DISSECTOR_KEY_IPV4_ADDRS;
	keys->ports.src = fl4->fl4_sport;
	keys->ports.dst = fl4->fl4_dport;
	keys->keyid.keyid = fl4->fl4_gre_key;
	keys->basic.ip_proto = fl4->flowi4_proto;

	return flow_hash_from_keys(keys);
}
EXPORT_SYMBOL(__get_hash_from_flowi4);

1306
static const struct flow_dissector_key flow_keys_dissector_keys[] = {
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	{
		.key_id = FLOW_DISSECTOR_KEY_CONTROL,
		.offset = offsetof(struct flow_keys, control),
	},
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	{
		.key_id = FLOW_DISSECTOR_KEY_BASIC,
		.offset = offsetof(struct flow_keys, basic),
	},
	{
		.key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS,
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		.offset = offsetof(struct flow_keys, addrs.v4addrs),
	},
	{
		.key_id = FLOW_DISSECTOR_KEY_IPV6_ADDRS,
		.offset = offsetof(struct flow_keys, addrs.v6addrs),
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	},
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	{
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		.key_id = FLOW_DISSECTOR_KEY_TIPC,
		.offset = offsetof(struct flow_keys, addrs.tipckey),
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	},
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	{
		.key_id = FLOW_DISSECTOR_KEY_PORTS,
		.offset = offsetof(struct flow_keys, ports),
	},
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	{
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		.key_id = FLOW_DISSECTOR_KEY_VLAN,
		.offset = offsetof(struct flow_keys, vlan),
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	},
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	{
		.key_id = FLOW_DISSECTOR_KEY_FLOW_LABEL,
		.offset = offsetof(struct flow_keys, tags),
	},
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	{
		.key_id = FLOW_DISSECTOR_KEY_GRE_KEYID,
		.offset = offsetof(struct flow_keys, keyid),
	},
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};

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static const struct flow_dissector_key flow_keys_dissector_symmetric_keys[] = {
	{
		.key_id = FLOW_DISSECTOR_KEY_CONTROL,
		.offset = offsetof(struct flow_keys, control),
	},
	{
		.key_id = FLOW_DISSECTOR_KEY_BASIC,
		.offset = offsetof(struct flow_keys, basic),
	},
	{
		.key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS,
		.offset = offsetof(struct flow_keys, addrs.v4addrs),
	},
	{
		.key_id = FLOW_DISSECTOR_KEY_IPV6_ADDRS,
		.offset = offsetof(struct flow_keys, addrs.v6addrs),
	},
	{
		.key_id = FLOW_DISSECTOR_KEY_PORTS,
		.offset = offsetof(struct flow_keys, ports),
	},
};

1368
static const struct flow_dissector_key flow_keys_buf_dissector_keys[] = {
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	{
		.key_id = FLOW_DISSECTOR_KEY_CONTROL,
		.offset = offsetof(struct flow_keys, control),
	},
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	{
		.key_id = FLOW_DISSECTOR_KEY_BASIC,
		.offset = offsetof(struct flow_keys, basic),
	},
};

struct flow_dissector flow_keys_dissector __read_mostly;
EXPORT_SYMBOL(flow_keys_dissector);

struct flow_dissector flow_keys_buf_dissector __read_mostly;

static int __init init_default_flow_dissectors(void)
{
	skb_flow_dissector_init(&flow_keys_dissector,
				flow_keys_dissector_keys,
				ARRAY_SIZE(flow_keys_dissector_keys));
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	skb_flow_dissector_init(&flow_keys_dissector_symmetric,
				flow_keys_dissector_symmetric_keys,
				ARRAY_SIZE(flow_keys_dissector_symmetric_keys));
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	skb_flow_dissector_init(&flow_keys_buf_dissector,
				flow_keys_buf_dissector_keys,
				ARRAY_SIZE(flow_keys_buf_dissector_keys));
	return 0;
}

1398
core_initcall(init_default_flow_dissectors);