diff options
Diffstat (limited to 'net/core/flow_dissector.c')
-rw-r--r-- | net/core/flow_dissector.c | 199 |
1 files changed, 138 insertions, 61 deletions
diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c index 6883e22..6a49aca 100644 --- a/net/core/flow_dissector.c +++ b/net/core/flow_dissector.c @@ -13,6 +13,7 @@ #include <linux/if_tunnel.h> #include <linux/if_pppox.h> #include <linux/ppp_defs.h> +#include <linux/stddef.h> #include <net/flow_dissector.h> #include <scsi/fc/fc_fcoe.h> @@ -63,17 +64,6 @@ void skb_flow_dissector_init(struct flow_dissector *flow_dissector, } EXPORT_SYMBOL(skb_flow_dissector_init); -/* copy saddr & daddr, possibly using 64bit load/store - * Equivalent to : flow->src = iph->saddr; - * flow->dst = iph->daddr; - */ -static void iph_to_flow_copy_addrs(struct flow_keys *flow, const struct iphdr *iph) -{ - BUILD_BUG_ON(offsetof(typeof(*flow), dst) != - offsetof(typeof(*flow), src) + sizeof(flow->src)); - memcpy(&flow->src, &iph->saddr, sizeof(flow->src) + sizeof(flow->dst)); -} - /** * __skb_flow_get_ports - extract the upper layer ports and return them * @skb: sk_buff to extract the ports from @@ -111,17 +101,27 @@ 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 the struct flow_keys from either the skbuff - * or a raw buffer specified by the rest parameters + * 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_keys *flow, +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_basic *key_basic; + struct flow_dissector_key_addrs *key_addrs; + struct flow_dissector_key_ports *key_ports; u8 ip_proto; if (!data) { @@ -131,7 +131,12 @@ bool __skb_flow_dissect(const struct sk_buff *skb, struct flow_keys *flow, hlen = skb_headlen(skb); } - memset(flow, 0, sizeof(*flow)); + /* 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); again: switch (proto) { @@ -148,14 +153,13 @@ ip: if (ip_is_fragment(iph)) ip_proto = 0; - /* skip the address processing if skb is NULL. The assumption - * here is that if there is no skb we are not looking for flow - * info but lengths and protocols. - */ - if (!skb) + if (!skb_flow_dissector_uses_key(flow_dissector, + FLOW_DISSECTOR_KEY_IPV4_ADDRS)) break; - - iph_to_flow_copy_addrs(flow, iph); + key_addrs = skb_flow_dissector_target(flow_dissector, + FLOW_DISSECTOR_KEY_IPV4_ADDRS, + target_container); + memcpy(key_addrs, &iph->saddr, sizeof(*key_addrs)); break; } case htons(ETH_P_IPV6): { @@ -171,12 +175,15 @@ ipv6: ip_proto = iph->nexthdr; nhoff += sizeof(struct ipv6hdr); - /* see comment above in IPv4 section */ - if (!skb) + if (!skb_flow_dissector_uses_key(flow_dissector, + FLOW_DISSECTOR_KEY_IPV6_HASH_ADDRS)) break; + key_addrs = skb_flow_dissector_target(flow_dissector, + FLOW_DISSECTOR_KEY_IPV6_HASH_ADDRS, + target_container); - flow->src = (__force __be32)ipv6_addr_hash(&iph->saddr); - flow->dst = (__force __be32)ipv6_addr_hash(&iph->daddr); + key_addrs->src = (__force __be32)ipv6_addr_hash(&iph->saddr); + key_addrs->dst = (__force __be32)ipv6_addr_hash(&iph->daddr); flow_label = ip6_flowlabel(iph); if (flow_label) { @@ -184,10 +191,18 @@ ipv6: * use that to represent the ports without any * further dissection. */ - flow->n_proto = proto; - flow->ip_proto = ip_proto; - flow->ports = flow_label; - flow->thoff = (u16)nhoff; + + key_basic->n_proto = proto; + key_basic->ip_proto = ip_proto; + key_basic->thoff = (u16)nhoff; + + if (!skb_flow_dissector_uses_key(flow_dissector, + FLOW_DISSECTOR_KEY_PORTS)) + break; + key_ports = skb_flow_dissector_target(flow_dissector, + FLOW_DISSECTOR_KEY_PORTS, + target_container); + key_ports->ports = flow_label; return true; } @@ -234,14 +249,22 @@ ipv6: hdr = __skb_header_pointer(skb, nhoff, sizeof(_hdr), data, hlen, &_hdr); if (!hdr) return false; - flow->src = hdr->srcnode; - flow->dst = 0; - flow->n_proto = proto; - flow->thoff = (u16)nhoff; + key_basic->n_proto = proto; + key_basic->thoff = (u16)nhoff; + + if (skb_flow_dissector_uses_key(flow_dissector, + FLOW_DISSECTOR_KEY_IPV6_HASH_ADDRS)) { + return true; + key_addrs = skb_flow_dissector_target(flow_dissector, + FLOW_DISSECTOR_KEY_IPV6_HASH_ADDRS, + target_container); + key_addrs->src = hdr->srcnode; + key_addrs->dst = 0; + } return true; } case htons(ETH_P_FCOE): - flow->thoff = (u16)(nhoff + FCOE_HEADER_LEN); + key_basic->thoff = (u16)(nhoff + FCOE_HEADER_LEN); /* fall through */ default: return false; @@ -296,14 +319,24 @@ ipv6: break; } - flow->n_proto = proto; - flow->ip_proto = ip_proto; - flow->thoff = (u16) nhoff; - - /* unless skb is set we don't need to record port info */ - if (skb) - flow->ports = __skb_flow_get_ports(skb, nhoff, ip_proto, - data, hlen); + /* 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); + key_basic->n_proto = proto; + key_basic->ip_proto = ip_proto; + key_basic->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; } @@ -325,16 +358,16 @@ static inline u32 __flow_hash_from_keys(struct flow_keys *keys, u32 keyval) u32 hash; /* get a consistent hash (same value on both flow directions) */ - if (((__force u32)keys->dst < (__force u32)keys->src) || - (((__force u32)keys->dst == (__force u32)keys->src) && - ((__force u16)keys->port16[1] < (__force u16)keys->port16[0]))) { - swap(keys->dst, keys->src); - swap(keys->port16[0], keys->port16[1]); + if (((__force u32)keys->addrs.dst < (__force u32)keys->addrs.src) || + (((__force u32)keys->addrs.dst == (__force u32)keys->addrs.src) && + ((__force u16)keys->ports.port16[1] < (__force u16)keys->ports.port16[0]))) { + swap(keys->addrs.dst, keys->addrs.src); + swap(keys->ports.port16[0], keys->ports.port16[1]); } - hash = __flow_hash_3words((__force u32)keys->dst, - (__force u32)keys->src, - (__force u32)keys->ports, + hash = __flow_hash_3words((__force u32)keys->addrs.dst, + (__force u32)keys->addrs.src, + (__force u32)keys->ports.ports, keyval); if (!hash) hash = 1; @@ -352,7 +385,7 @@ 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(skb, keys)) + if (!skb_flow_dissect_flow_keys(skb, keys)) return 0; return __flow_hash_from_keys(keys, keyval); @@ -377,11 +410,11 @@ void make_flow_keys_digest(struct flow_keys_digest *digest, memset(digest, 0, sizeof(*digest)); - data->n_proto = flow->n_proto; - data->ip_proto = flow->ip_proto; - data->ports = flow->ports; - data->src = flow->src; - data->dst = flow->dst; + data->n_proto = flow->basic.n_proto; + data->ip_proto = flow->basic.ip_proto; + data->ports = flow->ports.ports; + data->src = flow->addrs.src; + data->dst = flow->addrs.dst; } EXPORT_SYMBOL(make_flow_keys_digest); @@ -404,7 +437,7 @@ void __skb_get_hash(struct sk_buff *skb) hash = ___skb_get_hash(skb, &keys, hashrnd); if (!hash) return; - if (keys.ports) + if (keys.ports.ports) skb->l4_hash = 1; skb->sw_hash = 1; skb->hash = hash; @@ -422,9 +455,9 @@ 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->thoff; + u32 poff = keys->basic.thoff; - switch (keys->ip_proto) { + switch (keys->basic.ip_proto) { case IPPROTO_TCP: { /* access doff as u8 to avoid unaligned access */ const u8 *doff; @@ -478,8 +511,52 @@ u32 skb_get_poff(const struct sk_buff *skb) { struct flow_keys keys; - if (!skb_flow_dissect(skb, &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_BASIC, + .offset = offsetof(struct flow_keys, basic), + }, + { + .key_id = FLOW_DISSECTOR_KEY_IPV4_ADDRS, + .offset = offsetof(struct flow_keys, addrs), + }, + { + .key_id = FLOW_DISSECTOR_KEY_IPV6_HASH_ADDRS, + .offset = offsetof(struct flow_keys, addrs), + }, + { + .key_id = FLOW_DISSECTOR_KEY_PORTS, + .offset = offsetof(struct flow_keys, ports), + }, +}; + +static const struct flow_dissector_key flow_keys_buf_dissector_keys[] = { + { + .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); |