tools/testing/selftests/bpf/progs/mptcp_subflow.c

Source file repositories/reference/linux-study-clean/tools/testing/selftests/bpf/progs/mptcp_subflow.c

File Facts

System
Linux kernel
Corpus path
tools/testing/selftests/bpf/progs/mptcp_subflow.c
Extension
.c
Size
3014 bytes
Lines
129
Domain
Support Tooling And Documentation
Bucket
tools
Inferred role
Support Tooling And Documentation: implementation source
Status
source implementation candidate

Why This File Exists

Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.

Dependency Surface

Detected Declarations

Annotated Snippet

if (ssk->sk_mark != ++i) {
			ctx->retval = -2;
			break;
		}
	}

	return 1;
}

static int _check_getsockopt_subflow_cc(struct mptcp_sock *msk, struct bpf_sockopt *ctx)
{
	struct mptcp_subflow_context *subflow;

	mptcp_for_each_subflow(msk, subflow) {
		struct inet_connection_sock *icsk;
		struct sock *ssk;

		ssk = mptcp_subflow_tcp_sock(bpf_core_cast(subflow,
							   struct mptcp_subflow_context));
		icsk = bpf_core_cast(ssk, struct inet_connection_sock);

		if (ssk->sk_mark == 2 &&
		    __builtin_memcmp(icsk->icsk_ca_ops->name, cc, TCP_CA_NAME_MAX)) {
			ctx->retval = -2;
			break;
		}
	}

	return 1;
}

SEC("cgroup/getsockopt")
int _getsockopt_subflow(struct bpf_sockopt *ctx)
{
	struct bpf_sock *sk = ctx->sk;
	struct mptcp_sock *msk;

	if (bpf_get_current_pid_tgid() >> 32 != pid)
		return 1;

	if (!sk || sk->protocol != IPPROTO_MPTCP ||
	    (!(ctx->level == SOL_SOCKET && ctx->optname == SO_MARK) &&
	     !(ctx->level == SOL_TCP && ctx->optname == TCP_CONGESTION)))
		return 1;

	msk = bpf_core_cast(sk, struct mptcp_sock);
	if (msk->pm.extra_subflows != 1) {
		ctx->retval = -1;
		return 1;
	}

	if (ctx->optname == SO_MARK)
		return _check_getsockopt_subflow_mark(msk, ctx);
	return _check_getsockopt_subflow_cc(msk, ctx);
}

Annotation

Implementation Notes