flow_dissector.c 37.5 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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#include <uapi/linux/batadv_packet.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;
}

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void
skb_flow_dissect_tunnel_info(const struct sk_buff *skb,
			     struct flow_dissector *flow_dissector,
			     void *target_container)
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{
	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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EXPORT_SYMBOL(skb_flow_dissect_tunnel_info);
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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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/**
 * __skb_flow_dissect_batadv() - dissect batman-adv header
 * @skb: sk_buff to with the batman-adv header
 * @key_control: flow dissectors control key
 * @data: raw buffer pointer to the packet, if NULL use skb->data
 * @p_proto: pointer used to update the protocol to process next
 * @p_nhoff: pointer used to update inner network header offset
 * @hlen: packet header length
 * @flags: any combination of FLOW_DISSECTOR_F_*
 *
 * ETH_P_BATMAN packets are tried to be dissected. Only
 * &struct batadv_unicast packets are actually processed because they contain an
 * inner ethernet header and are usually followed by actual network header. This
 * allows the flow dissector to continue processing the packet.
 *
 * Return: FLOW_DISSECT_RET_PROTO_AGAIN when &struct batadv_unicast was found,
 *  FLOW_DISSECT_RET_OUT_GOOD when dissector should stop after encapsulation,
 *  otherwise FLOW_DISSECT_RET_OUT_BAD
 */
static enum flow_dissect_ret
__skb_flow_dissect_batadv(const struct sk_buff *skb,
			  struct flow_dissector_key_control *key_control,
			  void *data, __be16 *p_proto, int *p_nhoff, int hlen,
			  unsigned int flags)
{
	struct {
		struct batadv_unicast_packet batadv_unicast;
		struct ethhdr eth;
	} *hdr, _hdr;

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

	if (hdr->batadv_unicast.version != BATADV_COMPAT_VERSION)
		return FLOW_DISSECT_RET_OUT_BAD;

	if (hdr->batadv_unicast.packet_type != BATADV_UNICAST)
		return FLOW_DISSECT_RET_OUT_BAD;

	*p_proto = hdr->eth.h_proto;
	*p_nhoff += sizeof(*hdr);

	key_control->flags |= FLOW_DIS_ENCAPSULATION;
	if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP)
		return FLOW_DISSECT_RET_OUT_GOOD;

	return FLOW_DISSECT_RET_PROTO_AGAIN;
}

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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;
S
Simon Horman 已提交
588
	struct flow_dissector_key_icmp *key_icmp;
T
Tom Herbert 已提交
589
	struct flow_dissector_key_tags *key_tags;
590
	struct flow_dissector_key_vlan *key_vlan;
591
	enum flow_dissect_ret fdret;
592
	bool skip_vlan = false;
593
	int num_hdrs = 0;
594
	u8 ip_proto = 0;
595
	bool ret;
E
Eric Dumazet 已提交
596

597 598
	if (!data) {
		data = skb->data;
599 600
		proto = skb_vlan_tag_present(skb) ?
			 skb->vlan_proto : skb->protocol;
601
		nhoff = skb_network_offset(skb);
602
		hlen = skb_headlen(skb);
603
#if IS_ENABLED(CONFIG_NET_DSA)
604
		if (unlikely(skb->dev && netdev_uses_dsa(skb->dev))) {
605 606 607 608 609 610 611 612 613 614
			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;
			}
		}
615
#endif
616 617
	}

618 619 620 621 622 623 624
	/* 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);

625 626 627 628 629 630
	/* 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);
E
Eric Dumazet 已提交
631

632 633
	if (dissector_uses_key(flow_dissector,
			       FLOW_DISSECTOR_KEY_ETH_ADDRS)) {
634 635 636 637 638 639 640 641 642
		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));
	}

643
proto_again:
644 645
	fdret = FLOW_DISSECT_RET_CONTINUE;

E
Eric Dumazet 已提交
646
	switch (proto) {
647
	case htons(ETH_P_IP): {
E
Eric Dumazet 已提交
648 649
		const struct iphdr *iph;
		struct iphdr _iph;
650

651
		iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph);
652 653 654 655 656
		if (!iph || iph->ihl < 5) {
			fdret = FLOW_DISSECT_RET_OUT_BAD;
			break;
		}

657
		nhoff += iph->ihl * 4;
E
Eric Dumazet 已提交
658

659 660
		ip_proto = iph->protocol;

661 662 663 664 665 666 667 668 669 670
		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;
		}
671 672

		if (ip_is_fragment(iph)) {
673
			key_control->flags |= FLOW_DIS_IS_FRAGMENT;
674 675

			if (iph->frag_off & htons(IP_OFFSET)) {
676 677
				fdret = FLOW_DISSECT_RET_OUT_GOOD;
				break;
678
			} else {
679
				key_control->flags |= FLOW_DIS_FIRST_FRAG;
680 681 682 683 684
				if (!(flags &
				      FLOW_DISSECTOR_F_PARSE_1ST_FRAG)) {
					fdret = FLOW_DISSECT_RET_OUT_GOOD;
					break;
				}
685 686 687
			}
		}

688 689 690
		__skb_flow_dissect_ipv4(skb, flow_dissector,
					target_container, data, iph);

691 692 693 694
		if (flags & FLOW_DISSECTOR_F_STOP_AT_L3) {
			fdret = FLOW_DISSECT_RET_OUT_GOOD;
			break;
		}
695

E
Eric Dumazet 已提交
696 697
		break;
	}
698
	case htons(ETH_P_IPV6): {
E
Eric Dumazet 已提交
699 700
		const struct ipv6hdr *iph;
		struct ipv6hdr _iph;
701

702
		iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph);
703 704 705 706
		if (!iph) {
			fdret = FLOW_DISSECT_RET_OUT_BAD;
			break;
		}
E
Eric Dumazet 已提交
707 708 709

		ip_proto = iph->nexthdr;
		nhoff += sizeof(struct ipv6hdr);
710

711 712
		if (dissector_uses_key(flow_dissector,
				       FLOW_DISSECTOR_KEY_IPV6_ADDRS)) {
713 714 715
			key_addrs = skb_flow_dissector_target(flow_dissector,
							      FLOW_DISSECTOR_KEY_IPV6_ADDRS,
							      target_container);
716

717 718
			memcpy(&key_addrs->v6addrs, &iph->saddr,
			       sizeof(key_addrs->v6addrs));
719
			key_control->addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
720
		}
721

722 723 724 725 726 727
		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);

728 729
			if (dissector_uses_key(flow_dissector,
					       FLOW_DISSECTOR_KEY_FLOW_LABEL)) {
730 731 732 733
				key_tags = skb_flow_dissector_target(flow_dissector,
								     FLOW_DISSECTOR_KEY_FLOW_LABEL,
								     target_container);
				key_tags->flow_label = ntohl(flow_label);
734
			}
735 736 737 738
			if (flags & FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL) {
				fdret = FLOW_DISSECT_RET_OUT_GOOD;
				break;
			}
739 740
		}

741 742 743
		__skb_flow_dissect_ipv6(skb, flow_dissector,
					target_container, data, iph);

744
		if (flags & FLOW_DISSECTOR_F_STOP_AT_L3)
745
			fdret = FLOW_DISSECT_RET_OUT_GOOD;
746

E
Eric Dumazet 已提交
747 748
		break;
	}
749 750
	case htons(ETH_P_8021AD):
	case htons(ETH_P_8021Q): {
E
Eric Dumazet 已提交
751
		const struct vlan_hdr *vlan;
752 753
		struct vlan_hdr _vlan;
		bool vlan_tag_present = skb && skb_vlan_tag_present(skb);
754
		__be16 saved_vlan_tpid = proto;
E
Eric Dumazet 已提交
755

756
		if (vlan_tag_present)
757 758
			proto = skb->protocol;

759
		if (!vlan_tag_present || eth_type_vlan(skb->protocol)) {
760 761
			vlan = __skb_header_pointer(skb, nhoff, sizeof(_vlan),
						    data, hlen, &_vlan);
762 763 764 765 766
			if (!vlan) {
				fdret = FLOW_DISSECT_RET_OUT_BAD;
				break;
			}

767 768
			proto = vlan->h_vlan_encapsulated_proto;
			nhoff += sizeof(*vlan);
769 770 771 772
			if (skip_vlan) {
				fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
				break;
			}
773
		}
E
Eric Dumazet 已提交
774

775
		skip_vlan = true;
776
		if (dissector_uses_key(flow_dissector,
777 778 779
				       FLOW_DISSECTOR_KEY_VLAN)) {
			key_vlan = skb_flow_dissector_target(flow_dissector,
							     FLOW_DISSECTOR_KEY_VLAN,
T
Tom Herbert 已提交
780 781
							     target_container);

782
			if (vlan_tag_present) {
783 784 785 786 787
				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) &
788
					VLAN_VID_MASK;
789 790 791 792
				key_vlan->vlan_priority =
					(ntohs(vlan->h_vlan_TCI) &
					 VLAN_PRIO_MASK) >> VLAN_PRIO_SHIFT;
			}
793
			key_vlan->vlan_tpid = saved_vlan_tpid;
T
Tom Herbert 已提交
794 795
		}

796 797
		fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
		break;
E
Eric Dumazet 已提交
798
	}
799
	case htons(ETH_P_PPP_SES): {
E
Eric Dumazet 已提交
800 801 802 803
		struct {
			struct pppoe_hdr hdr;
			__be16 proto;
		} *hdr, _hdr;
804
		hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
805 806 807 808 809
		if (!hdr) {
			fdret = FLOW_DISSECT_RET_OUT_BAD;
			break;
		}

E
Eric Dumazet 已提交
810 811 812
		proto = hdr->proto;
		nhoff += PPPOE_SES_HLEN;
		switch (proto) {
813
		case htons(PPP_IP):
814 815 816
			proto = htons(ETH_P_IP);
			fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
			break;
817
		case htons(PPP_IPV6):
818 819 820
			proto = htons(ETH_P_IPV6);
			fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
			break;
E
Eric Dumazet 已提交
821
		default:
822 823
			fdret = FLOW_DISSECT_RET_OUT_BAD;
			break;
E
Eric Dumazet 已提交
824
		}
825
		break;
E
Eric Dumazet 已提交
826
	}
E
Erik Hugne 已提交
827
	case htons(ETH_P_TIPC): {
828 829 830 831
		struct tipc_basic_hdr *hdr, _hdr;

		hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr),
					   data, hlen, &_hdr);
832 833 834 835
		if (!hdr) {
			fdret = FLOW_DISSECT_RET_OUT_BAD;
			break;
		}
836

837
		if (dissector_uses_key(flow_dissector,
838
				       FLOW_DISSECTOR_KEY_TIPC)) {
839
			key_addrs = skb_flow_dissector_target(flow_dissector,
840
							      FLOW_DISSECTOR_KEY_TIPC,
841
							      target_container);
842 843
			key_addrs->tipckey.key = tipc_hdr_rps_key(hdr);
			key_control->addr_type = FLOW_DISSECTOR_KEY_TIPC;
844
		}
845 846
		fdret = FLOW_DISSECT_RET_OUT_GOOD;
		break;
E
Erik Hugne 已提交
847
	}
848 849

	case htons(ETH_P_MPLS_UC):
850
	case htons(ETH_P_MPLS_MC):
851
		fdret = __skb_flow_dissect_mpls(skb, flow_dissector,
852
						target_container, data,
853 854
						nhoff, hlen);
		break;
855
	case htons(ETH_P_FCOE):
856 857 858 859
		if ((hlen - nhoff) < FCOE_HEADER_LEN) {
			fdret = FLOW_DISSECT_RET_OUT_BAD;
			break;
		}
860 861

		nhoff += FCOE_HEADER_LEN;
862 863
		fdret = FLOW_DISSECT_RET_OUT_GOOD;
		break;
S
Simon Horman 已提交
864 865

	case htons(ETH_P_ARP):
866
	case htons(ETH_P_RARP):
867
		fdret = __skb_flow_dissect_arp(skb, flow_dissector,
868
					       target_container, data,
869 870 871
					       nhoff, hlen);
		break;

872 873 874 875 876
	case htons(ETH_P_BATMAN):
		fdret = __skb_flow_dissect_batadv(skb, key_control, data,
						  &proto, &nhoff, hlen, flags);
		break;

877 878 879 880 881 882 883 884 885 886
	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:
887 888 889
		if (skb_flow_dissect_allowed(&num_hdrs))
			goto proto_again;
		goto out_good;
890 891 892 893
	case FLOW_DISSECT_RET_CONTINUE:
	case FLOW_DISSECT_RET_IPPROTO_AGAIN:
		break;
	case FLOW_DISSECT_RET_OUT_BAD:
E
Eric Dumazet 已提交
894
	default:
895
		goto out_bad;
E
Eric Dumazet 已提交
896 897
	}

898
ip_proto_again:
899 900
	fdret = FLOW_DISSECT_RET_CONTINUE;

E
Eric Dumazet 已提交
901
	switch (ip_proto) {
902
	case IPPROTO_GRE:
903
		fdret = __skb_flow_dissect_gre(skb, key_control, flow_dissector,
904
					       target_container, data,
905 906 907
					       &proto, &nhoff, &hlen, flags);
		break;

908 909 910 911 912 913 914 915 916 917
	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);
918 919 920 921
		if (!opthdr) {
			fdret = FLOW_DISSECT_RET_OUT_BAD;
			break;
		}
922

923 924
		ip_proto = opthdr[0];
		nhoff += (opthdr[1] + 1) << 3;
925

926 927
		fdret = FLOW_DISSECT_RET_IPPROTO_AGAIN;
		break;
928
	}
929 930 931 932 933 934 935 936 937
	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);

938 939 940 941
		if (!fh) {
			fdret = FLOW_DISSECT_RET_OUT_BAD;
			break;
		}
942

943
		key_control->flags |= FLOW_DIS_IS_FRAGMENT;
944 945

		nhoff += sizeof(_fh);
946
		ip_proto = fh->nexthdr;
947 948

		if (!(fh->frag_off & htons(IP6_OFFSET))) {
949
			key_control->flags |= FLOW_DIS_FIRST_FRAG;
950 951 952 953
			if (flags & FLOW_DISSECTOR_F_PARSE_1ST_FRAG) {
				fdret = FLOW_DISSECT_RET_IPPROTO_AGAIN;
				break;
			}
954
		}
955 956 957

		fdret = FLOW_DISSECT_RET_OUT_GOOD;
		break;
958
	}
E
Eric Dumazet 已提交
959
	case IPPROTO_IPIP:
T
Tom Herbert 已提交
960
		proto = htons(ETH_P_IP);
961

962
		key_control->flags |= FLOW_DIS_ENCAPSULATION;
963 964 965 966 967 968 969
		if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP) {
			fdret = FLOW_DISSECT_RET_OUT_GOOD;
			break;
		}

		fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
		break;
970

971 972
	case IPPROTO_IPV6:
		proto = htons(ETH_P_IPV6);
973

974
		key_control->flags |= FLOW_DIS_ENCAPSULATION;
975 976 977 978 979 980 981 982
		if (flags & FLOW_DISSECTOR_F_STOP_AT_ENCAP) {
			fdret = FLOW_DISSECT_RET_OUT_GOOD;
			break;
		}

		fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
		break;

983

984 985
	case IPPROTO_MPLS:
		proto = htons(ETH_P_MPLS_UC);
986 987 988
		fdret = FLOW_DISSECT_RET_PROTO_AGAIN;
		break;

989 990 991 992
	case IPPROTO_TCP:
		__skb_flow_dissect_tcp(skb, flow_dissector, target_container,
				       data, nhoff, hlen);
		break;
993

E
Eric Dumazet 已提交
994 995 996 997
	default:
		break;
	}

998 999
	if (dissector_uses_key(flow_dissector,
			       FLOW_DISSECTOR_KEY_PORTS)) {
1000 1001 1002 1003 1004 1005
		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);
	}
1006

S
Simon Horman 已提交
1007 1008 1009 1010 1011 1012 1013 1014
	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);
	}

1015 1016 1017
	/* Process result of IP proto processing */
	switch (fdret) {
	case FLOW_DISSECT_RET_PROTO_AGAIN:
1018 1019 1020
		if (skb_flow_dissect_allowed(&num_hdrs))
			goto proto_again;
		break;
1021
	case FLOW_DISSECT_RET_IPPROTO_AGAIN:
1022 1023 1024
		if (skb_flow_dissect_allowed(&num_hdrs))
			goto ip_proto_again;
		break;
1025 1026 1027 1028 1029 1030 1031 1032
	case FLOW_DISSECT_RET_OUT_GOOD:
	case FLOW_DISSECT_RET_CONTINUE:
		break;
	case FLOW_DISSECT_RET_OUT_BAD:
	default:
		goto out_bad;
	}

1033 1034 1035
out_good:
	ret = true;

1036
out:
1037
	key_control->thoff = min_t(u16, nhoff, skb ? skb->len : hlen);
1038 1039 1040 1041
	key_basic->n_proto = proto;
	key_basic->ip_proto = ip_proto;

	return ret;
1042 1043 1044 1045

out_bad:
	ret = false;
	goto out;
E
Eric Dumazet 已提交
1046
}
1047
EXPORT_SYMBOL(__skb_flow_dissect);
1048 1049

static u32 hashrnd __read_mostly;
1050 1051 1052 1053 1054
static __always_inline void __flow_hash_secret_init(void)
{
	net_get_random_once(&hashrnd, sizeof(hashrnd));
}

1055 1056
static __always_inline u32 __flow_hash_words(const u32 *words, u32 length,
					     u32 keyval)
1057 1058 1059 1060
{
	return jhash2(words, length, keyval);
}

1061
static inline const u32 *flow_keys_hash_start(const struct flow_keys *flow)
1062
{
1063 1064
	const void *p = flow;

1065
	BUILD_BUG_ON(FLOW_KEYS_HASH_OFFSET % sizeof(u32));
1066
	return (const u32 *)(p + FLOW_KEYS_HASH_OFFSET);
1067 1068
}

1069
static inline size_t flow_keys_hash_length(const struct flow_keys *flow)
1070
{
1071
	size_t diff = FLOW_KEYS_HASH_OFFSET + sizeof(flow->addrs);
1072
	BUILD_BUG_ON((sizeof(*flow) - FLOW_KEYS_HASH_OFFSET) % sizeof(u32));
1073 1074 1075 1076 1077 1078 1079 1080 1081 1082
	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;
1083 1084
	case FLOW_DISSECTOR_KEY_TIPC:
		diff -= sizeof(flow->addrs.tipckey);
T
Tom Herbert 已提交
1085
		break;
1086 1087 1088 1089 1090 1091 1092 1093 1094 1095 1096 1097
	}
	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);
1098 1099
	case FLOW_DISSECTOR_KEY_TIPC:
		return flow->addrs.tipckey.key;
1100 1101 1102 1103 1104 1105 1106 1107 1108 1109 1110 1111 1112 1113 1114 1115 1116 1117 1118 1119 1120 1121 1122 1123 1124 1125 1126 1127 1128 1129 1130 1131 1132 1133 1134 1135 1136 1137 1138 1139 1140 1141 1142 1143 1144 1145 1146 1147 1148 1149 1150
	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;
	}
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}

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static inline u32 __flow_hash_from_keys(struct flow_keys *keys, u32 keyval)
1154 1155 1156
{
	u32 hash;

1157
	__flow_hash_consistentify(keys);
1158

1159
	hash = __flow_hash_words(flow_keys_hash_start(keys),
1160
				 flow_keys_hash_length(keys), keyval);
1161 1162 1163 1164 1165 1166 1167 1168
	if (!hash)
		hash = 1;

	return hash;
}

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

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static inline u32 ___skb_get_hash(const struct sk_buff *skb,
				  struct flow_keys *keys, u32 keyval)
{
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	skb_flow_dissect_flow_keys(skb, keys,
				   FLOW_DISSECTOR_F_STOP_AT_FLOW_LABEL);
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	return __flow_hash_from_keys(keys, keyval);
}

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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;

1212
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.
 */
1236
void __skb_get_hash(struct sk_buff *skb)
1237 1238
{
	struct flow_keys keys;
1239
	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));
1246
}
1247
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);

1257
u32 __skb_get_poff(const struct sk_buff *skb, void *data,
1258
		   const struct flow_keys_basic *keys, int hlen)
1259
{
1260
	u32 poff = keys->control.thoff;
1261

1262 1263 1264 1265 1266
	/* 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;

1267
	switch (keys->basic.ip_proto) {
1268
	case IPPROTO_TCP: {
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		/* access doff as u8 to avoid unaligned access */
		const u8 *doff;
		u8 _doff;
1272

1273 1274 1275
		doff = __skb_header_pointer(skb, poff + 12, sizeof(_doff),
					    data, hlen, &_doff);
		if (!doff)
1276 1277
			return poff;

1278
		poff += max_t(u32, sizeof(struct tcphdr), (*doff & 0xF0) >> 2);
1279 1280 1281 1282 1283 1284 1285 1286 1287 1288 1289 1290 1291 1292 1293 1294 1295 1296 1297 1298 1299 1300 1301 1302 1303 1304 1305 1306 1307
		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
1314 1315 1316 1317 1318
 * 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)
{
1319
	struct flow_keys_basic keys;
1320

1321
	if (!skb_flow_dissect_flow_keys_basic(skb, &keys, NULL, 0, 0, 0, 0))
1322 1323 1324 1325
		return 0;

	return __skb_get_poff(skb, skb->data, &keys, skb_headlen(skb));
}
1326

1327
__u32 __get_hash_from_flowi6(const struct flowi6 *fl6, struct flow_keys *keys)
1328 1329 1330 1331 1332 1333 1334 1335 1336 1337 1338
{
	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;
1339
	keys->tags.flow_label = (__force u32)flowi6_get_flowlabel(fl6);
1340 1341 1342 1343 1344 1345
	keys->basic.ip_proto = fl6->flowi6_proto;

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

1346
static const struct flow_dissector_key flow_keys_dissector_keys[] = {
1347 1348 1349 1350
	{
		.key_id = FLOW_DISSECTOR_KEY_CONTROL,
		.offset = offsetof(struct flow_keys, control),
	},
1351 1352 1353 1354 1355 1356
	{
		.key_id = FLOW_DISSECTOR_KEY_BASIC,
		.offset = offsetof(struct flow_keys, basic),
	},
	{
		.key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS,
1357 1358 1359 1360 1361
		.offset = offsetof(struct flow_keys, addrs.v4addrs),
	},
	{
		.key_id = FLOW_DISSECTOR_KEY_IPV6_ADDRS,
		.offset = offsetof(struct flow_keys, addrs.v6addrs),
1362
	},
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	{
1364 1365
		.key_id = FLOW_DISSECTOR_KEY_TIPC,
		.offset = offsetof(struct flow_keys, addrs.tipckey),
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	},
1367 1368 1369 1370
	{
		.key_id = FLOW_DISSECTOR_KEY_PORTS,
		.offset = offsetof(struct flow_keys, ports),
	},
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	{
1372 1373
		.key_id = FLOW_DISSECTOR_KEY_VLAN,
		.offset = offsetof(struct flow_keys, vlan),
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	},
1375 1376 1377 1378
	{
		.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),
	},
1383 1384
};

1385 1386 1387 1388 1389 1390 1391 1392 1393 1394 1395 1396 1397 1398 1399 1400 1401 1402 1403 1404 1405 1406 1407
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),
	},
};

1408
static const struct flow_dissector_key flow_keys_basic_dissector_keys[] = {
1409 1410 1411 1412
	{
		.key_id = FLOW_DISSECTOR_KEY_CONTROL,
		.offset = offsetof(struct flow_keys, control),
	},
1413 1414 1415 1416 1417 1418 1419 1420 1421
	{
		.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);

1422 1423
struct flow_dissector flow_keys_basic_dissector __read_mostly;
EXPORT_SYMBOL(flow_keys_basic_dissector);
1424 1425 1426 1427 1428 1429

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));
1430 1431 1432
	skb_flow_dissector_init(&flow_keys_dissector_symmetric,
				flow_keys_dissector_symmetric_keys,
				ARRAY_SIZE(flow_keys_dissector_symmetric_keys));
1433 1434 1435
	skb_flow_dissector_init(&flow_keys_basic_dissector,
				flow_keys_basic_dissector_keys,
				ARRAY_SIZE(flow_keys_basic_dissector_keys));
1436 1437 1438
	return 0;
}

1439
core_initcall(init_default_flow_dissectors);