Commit d58e468b authored by Petar Penkov's avatar Petar Penkov Committed by Alexei Starovoitov
Browse files

flow_dissector: implements flow dissector BPF hook 



Adds a hook for programs of type BPF_PROG_TYPE_FLOW_DISSECTOR and
attach type BPF_FLOW_DISSECTOR that is executed in the flow dissector
path. The BPF program is per-network namespace.

Signed-off-by: default avatarPetar Penkov <ppenkov@google.com>
Signed-off-by: default avatarWillem de Bruijn <willemb@google.com>
Signed-off-by: default avatarAlexei Starovoitov <ast@kernel.org>
parent 1edb6e03

include/linux/bpf.h

+1 −0
Original line number Diff line number Diff line
@@ -212,6 +212,7 @@ enum bpf_reg_type { 
	PTR_TO_PACKET_META,	 /* skb->data - meta_len */

	PTR_TO_PACKET,		 /* reg points to skb->data */

	PTR_TO_PACKET_END,	 /* skb->data + headlen */

	PTR_TO_FLOW_KEYS,	 /* reg points to bpf_flow_keys */

};



/* The information passed from prog-specific *_is_valid_access

include/linux/bpf_types.h

+1 −0
Original line number Diff line number Diff line
@@ -32,6 +32,7 @@ BPF_PROG_TYPE(BPF_PROG_TYPE_LIRC_MODE2, lirc_mode2) 
#ifdef CONFIG_INET

BPF_PROG_TYPE(BPF_PROG_TYPE_SK_REUSEPORT, sk_reuseport)

#endif

BPF_PROG_TYPE(BPF_PROG_TYPE_FLOW_DISSECTOR, flow_dissector)



BPF_MAP_TYPE(BPF_MAP_TYPE_ARRAY, array_map_ops)

BPF_MAP_TYPE(BPF_MAP_TYPE_PERCPU_ARRAY, percpu_array_map_ops)

include/linux/skbuff.h

+7 −0
Original line number Diff line number Diff line
@@ -243,6 +243,8 @@ struct scatterlist; 
struct pipe_inode_info;

struct iov_iter;

struct napi_struct;

struct bpf_prog;

union bpf_attr;



#if defined(CONFIG_NF_CONNTRACK) || defined(CONFIG_NF_CONNTRACK_MODULE)

struct nf_conntrack {
@@ -1192,6 +1194,11 @@ void skb_flow_dissector_init(struct flow_dissector *flow_dissector, 
			     const struct flow_dissector_key *key,

			     unsigned int key_count);



int skb_flow_dissector_bpf_prog_attach(const union bpf_attr *attr,

				       struct bpf_prog *prog);



int skb_flow_dissector_bpf_prog_detach(const union bpf_attr *attr);



bool __skb_flow_dissect(const struct sk_buff *skb,

			struct flow_dissector *flow_dissector,

			void *target_container,

include/net/net_namespace.h

+3 −0
Original line number Diff line number Diff line
@@ -43,6 +43,7 @@ struct ctl_table_header; 
struct net_generic;

struct uevent_sock;

struct netns_ipvs;

struct bpf_prog;





#define NETDEV_HASHBITS    8
@@ -145,6 +146,8 @@ struct net { 
#endif

	struct net_generic __rcu	*gen;



	struct bpf_prog __rcu	*flow_dissector_prog;



	/* Note : following structs are cache line aligned */

#ifdef CONFIG_XFRM

	struct netns_xfrm	xfrm;

include/net/sch_generic.h

+9 −3
Original line number Diff line number Diff line
@@ -19,6 +19,7 @@ struct Qdisc_ops; 
struct qdisc_walker;

struct tcf_walker;

struct module;

struct bpf_flow_keys;



typedef int tc_setup_cb_t(enum tc_setup_type type,

			  void *type_data, void *cb_priv);
@@ -307,9 +308,14 @@ struct tcf_proto { 
};



struct qdisc_skb_cb {

	union {

		struct {

			unsigned int		pkt_len;

			u16			slave_dev_queue_mapping;

			u16			tc_classid;

		};

		struct bpf_flow_keys *flow_keys;

	};

#define QDISC_CB_PRIV_LEN 20

	unsigned char		data[QDISC_CB_PRIV_LEN];

};

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