@@ -373,6 +373,14 @@ struct tcp_sock {
*/
struct request_sock *fastopen_rsk;
u32 *saved_syn;
+
+/* Sock_ops bpf program related variables */
+#ifdef CONFIG_BPF
+ u32 bpf_sock_ops_flags; /* values defined in uapi/linux/tcp.h */
+#define BPF_SOCK_OPS_TEST_FLAG(TP, ARG) (TP->bpf_sock_ops_flags & ARG)
+#else
+#define BPF_SOCK_OPS_TEST_FLAG(TP, ARG) 0
+#endif
};
enum tsq_enum {
@@ -959,6 +959,7 @@ struct bpf_sock_ops {
*/
__u32 snd_cwnd;
__u32 srtt_us; /* Averaged RTT << 3 in usecs */
+ __u32 bpf_sock_ops_flags; /* flags defined in uapi/linux/tcp.h */
};
/* List of known BPF sock_ops operators.
@@ -3843,6 +3843,7 @@ static bool sock_ops_is_valid_access(int off, int size,
switch (off) {
case offsetof(struct bpf_sock_ops, op) ...
offsetof(struct bpf_sock_ops, replylong[3]):
+ case offsetof(struct bpf_sock_ops, bpf_sock_ops_flags):
break;
default:
return false;
@@ -4525,6 +4526,12 @@ static u32 sock_ops_convert_ctx_access(enum bpf_access_type type,
case offsetof(struct bpf_sock_ops, srtt_us):
SOCK_OPS_GET_FIELD(srtt_us, srtt_us, struct tcp_sock);
break;
+
+ case offsetof(struct bpf_sock_ops, bpf_sock_ops_flags):
+ SOCK_OPS_GET_OR_SET_FIELD(bpf_sock_ops_flags,
+ bpf_sock_ops_flags,
+ struct tcp_sock, type);
+ break;
}
return insn - insn_buf;
}
Adds field bpf_sock_ops_flags to tcp_sock and bpf_sock_ops. Its primary use is to determine if there should be calls to sock_ops bpf program at various points in the TCP code. The field is initialized to zero, disabling the calls. A sock_ops BPF program can set, per connection and as necessary, when the connection is established. It also adds support for reading and writting the field within a sock_ops BPF program. Examples of where to call the bpf program: 1) When RTO fires 2) When a packet is retransmitted 3) When the connection terminates 4) When a packet is sent 5) When a packet is received Signed-off-by: Lawrence Brakmo <brakmo@fb.com> --- include/linux/tcp.h | 8 ++++++++ include/uapi/linux/bpf.h | 1 + net/core/filter.c | 7 +++++++ 3 files changed, 16 insertions(+)