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- #include <linux/kernel.h>
- #include <linux/skbuff.h>
- #include <linux/export.h>
- #include <linux/ip.h>
- #include <linux/ipv6.h>
- #include <linux/if_vlan.h>
- #include <net/ip.h>
- #include <net/ipv6.h>
- #include <linux/igmp.h>
- #include <linux/icmp.h>
- #include <linux/sctp.h>
- #include <linux/dccp.h>
- #include <linux/if_tunnel.h>
- #include <linux/if_pppox.h>
- #include <linux/ppp_defs.h>
- #include <linux/stddef.h>
- #include <linux/if_ether.h>
- #include <linux/mpls.h>
- #include <net/flow_dissector.h>
- #include <scsi/fc/fc_fcoe.h>
- static bool skb_flow_dissector_uses_key(struct flow_dissector *flow_dissector,
- enum flow_dissector_key_id key_id)
- {
- return flow_dissector->used_keys & (1 << key_id);
- }
- static void skb_flow_dissector_set_key(struct flow_dissector *flow_dissector,
- enum flow_dissector_key_id key_id)
- {
- flow_dissector->used_keys |= (1 << key_id);
- }
- static void *skb_flow_dissector_target(struct flow_dissector *flow_dissector,
- enum flow_dissector_key_id key_id,
- void *target_container)
- {
- return ((char *) target_container) + flow_dissector->offset[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);
- BUG_ON(skb_flow_dissector_uses_key(flow_dissector,
- key->key_id));
- skb_flow_dissector_set_key(flow_dissector, key->key_id);
- flow_dissector->offset[key->key_id] = key->offset;
- }
- /* Ensure that the dissector always includes control and basic key.
- * That way we are able to avoid handling lack of these in fast path.
- */
- BUG_ON(!skb_flow_dissector_uses_key(flow_dissector,
- FLOW_DISSECTOR_KEY_CONTROL));
- BUG_ON(!skb_flow_dissector_uses_key(flow_dissector,
- FLOW_DISSECTOR_KEY_BASIC));
- }
- EXPORT_SYMBOL(skb_flow_dissector_init);
- /**
- * __skb_flow_get_ports - extract the upper layer ports and return them
- * @skb: sk_buff to extract the ports from
- * @thoff: transport header offset
- * @ip_proto: protocol for which to get port offset
- * @data: raw buffer pointer to the packet, if NULL use skb->data
- * @hlen: packet header length, if @data is NULL use skb_headlen(skb)
- *
- * The function will try to retrieve the ports at offset thoff + poff where poff
- * is the protocol port offset returned from proto_ports_offset
- */
- __be32 __skb_flow_get_ports(const struct sk_buff *skb, int thoff, u8 ip_proto,
- void *data, int hlen)
- {
- int poff = proto_ports_offset(ip_proto);
- if (!data) {
- data = skb->data;
- hlen = skb_headlen(skb);
- }
- if (poff >= 0) {
- __be32 *ports, _ports;
- ports = __skb_header_pointer(skb, thoff + poff,
- sizeof(_ports), data, hlen, &_ports);
- if (ports)
- return *ports;
- }
- return 0;
- }
- EXPORT_SYMBOL(__skb_flow_get_ports);
- /**
- * __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
- * @flow_dissector: list of keys to dissect
- * @target_container: target structure to put dissected values into
- * @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)
- *
- * 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.
- */
- bool __skb_flow_dissect(const struct sk_buff *skb,
- struct flow_dissector *flow_dissector,
- void *target_container,
- void *data, __be16 proto, int nhoff, int hlen)
- {
- struct flow_dissector_key_control *key_control;
- struct flow_dissector_key_basic *key_basic;
- struct flow_dissector_key_addrs *key_addrs;
- struct flow_dissector_key_ports *key_ports;
- struct flow_dissector_key_tags *key_tags;
- struct flow_dissector_key_keyid *key_keyid;
- u8 ip_proto = 0;
- if (!data) {
- data = skb->data;
- proto = skb->protocol;
- nhoff = skb_network_offset(skb);
- hlen = skb_headlen(skb);
- }
- /* 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);
- /* 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);
- if (skb_flow_dissector_uses_key(flow_dissector,
- FLOW_DISSECTOR_KEY_ETH_ADDRS)) {
- 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, ð->h_dest, sizeof(*key_eth_addrs));
- }
- again:
- switch (proto) {
- case htons(ETH_P_IP): {
- const struct iphdr *iph;
- struct iphdr _iph;
- ip:
- iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph);
- if (!iph || iph->ihl < 5)
- return false;
- nhoff += iph->ihl * 4;
- ip_proto = iph->protocol;
- if (ip_is_fragment(iph))
- ip_proto = 0;
- if (!skb_flow_dissector_uses_key(flow_dissector,
- FLOW_DISSECTOR_KEY_IPV4_ADDRS))
- break;
- 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;
- break;
- }
- case htons(ETH_P_IPV6): {
- const struct ipv6hdr *iph;
- struct ipv6hdr _iph;
- __be32 flow_label;
- ipv6:
- iph = __skb_header_pointer(skb, nhoff, sizeof(_iph), data, hlen, &_iph);
- if (!iph)
- return false;
- ip_proto = iph->nexthdr;
- nhoff += sizeof(struct ipv6hdr);
- if (skb_flow_dissector_uses_key(flow_dissector,
- FLOW_DISSECTOR_KEY_IPV6_ADDRS)) {
- struct flow_dissector_key_ipv6_addrs *key_ipv6_addrs;
- key_ipv6_addrs = skb_flow_dissector_target(flow_dissector,
- FLOW_DISSECTOR_KEY_IPV6_ADDRS,
- target_container);
- memcpy(key_ipv6_addrs, &iph->saddr, sizeof(*key_ipv6_addrs));
- key_control->addr_type = FLOW_DISSECTOR_KEY_IPV6_ADDRS;
- }
- flow_label = ip6_flowlabel(iph);
- if (flow_label) {
- if (skb_flow_dissector_uses_key(flow_dissector,
- FLOW_DISSECTOR_KEY_FLOW_LABEL)) {
- key_tags = skb_flow_dissector_target(flow_dissector,
- FLOW_DISSECTOR_KEY_FLOW_LABEL,
- target_container);
- key_tags->flow_label = ntohl(flow_label);
- }
- }
- break;
- }
- case htons(ETH_P_8021AD):
- case htons(ETH_P_8021Q): {
- const struct vlan_hdr *vlan;
- struct vlan_hdr _vlan;
- vlan = __skb_header_pointer(skb, nhoff, sizeof(_vlan), data, hlen, &_vlan);
- if (!vlan)
- return false;
- if (skb_flow_dissector_uses_key(flow_dissector,
- FLOW_DISSECTOR_KEY_VLANID)) {
- key_tags = skb_flow_dissector_target(flow_dissector,
- FLOW_DISSECTOR_KEY_VLANID,
- target_container);
- key_tags->vlan_id = skb_vlan_tag_get_id(skb);
- }
- proto = vlan->h_vlan_encapsulated_proto;
- nhoff += sizeof(*vlan);
- goto again;
- }
- case htons(ETH_P_PPP_SES): {
- struct {
- struct pppoe_hdr hdr;
- __be16 proto;
- } *hdr, _hdr;
- hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
- if (!hdr)
- return false;
- proto = hdr->proto;
- nhoff += PPPOE_SES_HLEN;
- switch (proto) {
- case htons(PPP_IP):
- goto ip;
- case htons(PPP_IPV6):
- goto ipv6;
- default:
- return false;
- }
- }
- case htons(ETH_P_TIPC): {
- struct {
- __be32 pre[3];
- __be32 srcnode;
- } *hdr, _hdr;
- hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
- if (!hdr)
- return false;
- key_basic->n_proto = proto;
- key_control->thoff = (u16)nhoff;
- if (skb_flow_dissector_uses_key(flow_dissector,
- FLOW_DISSECTOR_KEY_TIPC_ADDRS)) {
- key_addrs = skb_flow_dissector_target(flow_dissector,
- FLOW_DISSECTOR_KEY_TIPC_ADDRS,
- target_container);
- key_addrs->tipcaddrs.srcnode = hdr->srcnode;
- key_control->addr_type = FLOW_DISSECTOR_KEY_TIPC_ADDRS;
- }
- return true;
- }
- case htons(ETH_P_MPLS_UC):
- case htons(ETH_P_MPLS_MC): {
- struct mpls_label *hdr, _hdr[2];
- mpls:
- hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data,
- hlen, &_hdr);
- if (!hdr)
- return false;
- if ((ntohl(hdr[0].entry) & MPLS_LS_LABEL_MASK) >>
- MPLS_LS_LABEL_SHIFT == MPLS_LABEL_ENTROPY) {
- if (skb_flow_dissector_uses_key(flow_dissector,
- FLOW_DISSECTOR_KEY_MPLS_ENTROPY)) {
- 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);
- }
- key_basic->n_proto = proto;
- key_basic->ip_proto = ip_proto;
- key_control->thoff = (u16)nhoff;
- return true;
- }
- return true;
- }
- case htons(ETH_P_FCOE):
- key_control->thoff = (u16)(nhoff + FCOE_HEADER_LEN);
- /* fall through */
- default:
- return false;
- }
- ip_proto_again:
- switch (ip_proto) {
- case IPPROTO_GRE: {
- struct gre_hdr {
- __be16 flags;
- __be16 proto;
- } *hdr, _hdr;
- hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr);
- if (!hdr)
- return false;
- /*
- * Only look inside GRE if version zero and no
- * routing
- */
- if (hdr->flags & (GRE_VERSION | GRE_ROUTING))
- break;
- proto = hdr->proto;
- nhoff += 4;
- if (hdr->flags & GRE_CSUM)
- nhoff += 4;
- if (hdr->flags & GRE_KEY) {
- const __be32 *keyid;
- __be32 _keyid;
- keyid = __skb_header_pointer(skb, nhoff, sizeof(_keyid),
- data, hlen, &_keyid);
- if (!keyid)
- return false;
- if (skb_flow_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);
- key_keyid->keyid = *keyid;
- }
- nhoff += 4;
- }
- if (hdr->flags & GRE_SEQ)
- nhoff += 4;
- if (proto == htons(ETH_P_TEB)) {
- const struct ethhdr *eth;
- struct ethhdr _eth;
- eth = __skb_header_pointer(skb, nhoff,
- sizeof(_eth),
- data, hlen, &_eth);
- if (!eth)
- return false;
- proto = eth->h_proto;
- nhoff += sizeof(*eth);
- }
- goto again;
- }
- 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);
- if (!opthdr)
- return false;
- ip_proto = opthdr[0];
- nhoff += (opthdr[1] + 1) << 3;
- goto ip_proto_again;
- }
- case IPPROTO_IPIP:
- proto = htons(ETH_P_IP);
- goto ip;
- case IPPROTO_IPV6:
- proto = htons(ETH_P_IPV6);
- goto ipv6;
- case IPPROTO_MPLS:
- proto = htons(ETH_P_MPLS_UC);
- goto mpls;
- default:
- break;
- }
- key_basic->n_proto = proto;
- key_basic->ip_proto = ip_proto;
- key_control->thoff = (u16)nhoff;
- if (skb_flow_dissector_uses_key(flow_dissector,
- FLOW_DISSECTOR_KEY_PORTS)) {
- 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);
- }
- return true;
- }
- EXPORT_SYMBOL(__skb_flow_dissect);
- static u32 hashrnd __read_mostly;
- static __always_inline void __flow_hash_secret_init(void)
- {
- net_get_random_once(&hashrnd, sizeof(hashrnd));
- }
- static __always_inline u32 __flow_hash_words(u32 *words, u32 length, u32 keyval)
- {
- return jhash2(words, length, keyval);
- }
- static inline void *flow_keys_hash_start(struct flow_keys *flow)
- {
- BUILD_BUG_ON(FLOW_KEYS_HASH_OFFSET % sizeof(u32));
- return (void *)flow + FLOW_KEYS_HASH_OFFSET;
- }
- static inline size_t flow_keys_hash_length(struct flow_keys *flow)
- {
- size_t diff = FLOW_KEYS_HASH_OFFSET + sizeof(flow->addrs);
- BUILD_BUG_ON((sizeof(*flow) - FLOW_KEYS_HASH_OFFSET) % sizeof(u32));
- 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;
- case FLOW_DISSECTOR_KEY_TIPC_ADDRS:
- diff -= sizeof(flow->addrs.tipcaddrs);
- break;
- }
- 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);
- case FLOW_DISSECTOR_KEY_TIPC_ADDRS:
- return flow->addrs.tipcaddrs.srcnode;
- 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;
- }
- }
- static inline u32 __flow_hash_from_keys(struct flow_keys *keys, u32 keyval)
- {
- u32 hash;
- __flow_hash_consistentify(keys);
- hash = __flow_hash_words((u32 *)flow_keys_hash_start(keys),
- flow_keys_hash_length(keys), keyval);
- if (!hash)
- hash = 1;
- return hash;
- }
- u32 flow_hash_from_keys(struct flow_keys *keys)
- {
- __flow_hash_secret_init();
- return __flow_hash_from_keys(keys, hashrnd);
- }
- EXPORT_SYMBOL(flow_hash_from_keys);
- static inline u32 ___skb_get_hash(const struct sk_buff *skb,
- struct flow_keys *keys, u32 keyval)
- {
- if (!skb_flow_dissect_flow_keys(skb, keys))
- return 0;
- return __flow_hash_from_keys(keys, keyval);
- }
- 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));
- data->n_proto = flow->basic.n_proto;
- data->ip_proto = flow->basic.ip_proto;
- data->ports = flow->ports.ports;
- data->src = flow->addrs.v4addrs.src;
- data->dst = flow->addrs.v4addrs.dst;
- }
- EXPORT_SYMBOL(make_flow_keys_digest);
- /**
- * __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
- * and src/dst port numbers. Sets hash in skb to non-zero hash value
- * on success, zero indicates no valid hash. Also, sets l4_hash in skb
- * if hash is a canonical 4-tuple hash over transport ports.
- */
- void __skb_get_hash(struct sk_buff *skb)
- {
- struct flow_keys keys;
- u32 hash;
- __flow_hash_secret_init();
- hash = ___skb_get_hash(skb, &keys, hashrnd);
- if (!hash)
- return;
- if (keys.ports.ports)
- skb->l4_hash = 1;
- skb->sw_hash = 1;
- skb->hash = hash;
- }
- EXPORT_SYMBOL(__skb_get_hash);
- __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);
- u32 __skb_get_poff(const struct sk_buff *skb, void *data,
- const struct flow_keys *keys, int hlen)
- {
- u32 poff = keys->control.thoff;
- switch (keys->basic.ip_proto) {
- case IPPROTO_TCP: {
- /* access doff as u8 to avoid unaligned access */
- const u8 *doff;
- u8 _doff;
- doff = __skb_header_pointer(skb, poff + 12, sizeof(_doff),
- data, hlen, &_doff);
- if (!doff)
- return poff;
- poff += max_t(u32, sizeof(struct tcphdr), (*doff & 0xF0) >> 2);
- 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;
- }
- /**
- * 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
- * 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;
- if (!skb_flow_dissect_flow_keys(skb, &keys))
- return 0;
- return __skb_get_poff(skb, skb->data, &keys, skb_headlen(skb));
- }
- static const struct flow_dissector_key flow_keys_dissector_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_TIPC_ADDRS,
- .offset = offsetof(struct flow_keys, addrs.tipcaddrs),
- },
- {
- .key_id = FLOW_DISSECTOR_KEY_PORTS,
- .offset = offsetof(struct flow_keys, ports),
- },
- {
- .key_id = FLOW_DISSECTOR_KEY_VLANID,
- .offset = offsetof(struct flow_keys, tags),
- },
- {
- .key_id = FLOW_DISSECTOR_KEY_FLOW_LABEL,
- .offset = offsetof(struct flow_keys, tags),
- },
- {
- .key_id = FLOW_DISSECTOR_KEY_GRE_KEYID,
- .offset = offsetof(struct flow_keys, keyid),
- },
- };
- static const struct flow_dissector_key flow_keys_buf_dissector_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),
- },
- };
- 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));
- skb_flow_dissector_init(&flow_keys_buf_dissector,
- flow_keys_buf_dissector_keys,
- ARRAY_SIZE(flow_keys_buf_dissector_keys));
- return 0;
- }
- late_initcall_sync(init_default_flow_dissectors);
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