[PATCH net-next,v2 03/12] flow_dissector: add flow action infrastructure

Pablo Neira Ayuso
2018-11-19T10:38:44Z

This new infrastructure defines the nic actions that you can perform
from existing network drivers. This infrastructure allows us to avoid a
direct dependency with the native software TC action representation.

Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
---
v2: no changes.

include/net/flow_dissector.h | 70 ++++++++++++++++++++++++++++++++++++++++++++
net/core/flow_dissector.c | 18 ++++++++++++
2 files changed, 88 insertions(+)

diff --git a/include/net/flow_dissector.h b/include/net/flow_dissector.h
index 965a82b8d881..925c208816f1 100644
--- a/include/net/flow_dissector.h
+++ b/include/net/flow_dissector.h
@@ -402,8 +402,78 @@ void flow_rule_match_enc_keyid(const struct flow_rule *rule,
void flow_rule_match_enc_opts(const struct flow_rule *rule,
struct flow_match_enc_opts *out);

+enum flow_action_key_id {
+ FLOW_ACTION_KEY_ACCEPT = 0,
+ FLOW_ACTION_KEY_DROP,
+ FLOW_ACTION_KEY_TRAP,
+ FLOW_ACTION_KEY_GOTO,
+ FLOW_ACTION_KEY_REDIRECT,
+ FLOW_ACTION_KEY_MIRRED,
+ FLOW_ACTION_KEY_VLAN_PUSH,
+ FLOW_ACTION_KEY_VLAN_POP,
+ FLOW_ACTION_KEY_VLAN_MANGLE,
+ FLOW_ACTION_KEY_TUNNEL_ENCAP,
+ FLOW_ACTION_KEY_TUNNEL_DECAP,
+ FLOW_ACTION_KEY_MANGLE,
+ FLOW_ACTION_KEY_ADD,
+ FLOW_ACTION_KEY_CSUM,
+ FLOW_ACTION_KEY_MARK,
+};
+
+/* This is mirroring enum pedit_header_type definition for easy mapping between
+ * tc pedit action. Legacy TCA_PEDIT_KEY_EX_HDR_TYPE_NETWORK is mapped to
+ * FLOW_ACT_MANGLE_UNSPEC, which is supported by no driver.
+ */
+enum flow_act_mangle_base {
+ FLOW_ACT_MANGLE_UNSPEC = 0,
+ FLOW_ACT_MANGLE_HDR_TYPE_ETH,
+ FLOW_ACT_MANGLE_HDR_TYPE_IP4,
+ FLOW_ACT_MANGLE_HDR_TYPE_IP6,
+ FLOW_ACT_MANGLE_HDR_TYPE_TCP,
+ FLOW_ACT_MANGLE_HDR_TYPE_UDP,
+};
+
+struct flow_action_key {
+ enum flow_action_key_id id;
+ union {
+ u32 chain_index; /* FLOW_ACTION_KEY_GOTO */
+ struct net_device *dev; /* FLOW_ACTION_KEY_REDIRECT */
+ struct { /* FLOW_ACTION_KEY_VLAN */
+ u16 vid;
+ __be16 proto;
+ u8 prio;
+ } vlan;
+ struct { /* FLOW_ACTION_KEY_PACKET_EDIT */
+ enum flow_act_mangle_base htype;
+ u32 offset;
+ u32 mask;
+ u32 val;
+ } mangle;
+ const struct ip_tunnel_info *tunnel; /* FLOW_ACTION_KEY_TUNNEL_ENCAP */
+ u32 csum_flags; /* FLOW_ACTION_KEY_CSUM */
+ u32 mark; /* FLOW_ACTION_KEY_MARK */
+ };
+};
+
+struct flow_action {
+ int num_keys;
+ struct flow_action_key *keys;
+};
+
+int flow_action_init(struct flow_action *flow_action, int num_acts);
+void flow_action_free(struct flow_action *flow_action);
+
+static inline bool flow_action_has_keys(const struct flow_action *action)
+{
+ return action->num_keys;
+}
+
+#define flow_action_for_each(__i, __act, __actions) \
+ for (__i = 0, __act = &(__actions)->keys[0]; __i < (__actions)->num_keys; __act = &(__actions)->keys[++__i])
+
struct flow_rule {
struct flow_match match;
+ struct flow_action action;
};

static inline bool flow_rule_match_key(const struct flow_rule *rule,
diff --git a/net/core/flow_dissector.c b/net/core/flow_dissector.c
index 186089b8d852..b9368349f0f7 100644
--- a/net/core/flow_dissector.c
+++ b/net/core/flow_dissector.c
@@ -258,6 +258,24 @@ void flow_rule_match_enc_opts(const struct flow_rule *rule,
}
EXPORT_SYMBOL(flow_rule_match_enc_opts);

+int flow_action_init(struct flow_action *flow_action, int num_acts)
+{
+ flow_action->keys = kmalloc(sizeof(struct flow_action_key) * num_acts,
+ GFP_KERNEL);
+ if (!flow_action->keys)
+ return -ENOMEM;
+
+ flow_action->num_keys = num_acts;
+ return 0;
+}
+EXPORT_SYMBOL(flow_action_init);
+
+void flow_action_free(struct flow_action *flow_action)
+{
+ kfree(flow_action->keys);
+}
+EXPORT_SYMBOL(flow_action_free);
+
/**
* __skb_flow_get_ports - extract the upper layer ports and return them
* @skb: sk_buff to extract the ports from
--
2.11.0