tools/testing/selftests/bpf/progs/test_skmsg_load_helpers.c
Source file repositories/reference/linux-study-clean/tools/testing/selftests/bpf/progs/test_skmsg_load_helpers.c
File Facts
- System
- Linux kernel
- Corpus path
tools/testing/selftests/bpf/progs/test_skmsg_load_helpers.c- Extension
.c- Size
- 1570 bytes
- Lines
- 71
- 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.
- Repository support layer: documentation, build tooling, samples, user-space helper tools, generated initramfs support, licenses, and validation utilities.
- Defines or uses C structs; map object ownership, embedded links, reference counts, and lock ownership.
Dependency Surface
vmlinux.hbpf/bpf_helpers.h
Detected Declarations
function prog_msg_verdict_commonfunction prog_msg_verdictfunction prog_msg_verdict_clonefunction prog_msg_verdict_clone2function prog_skb_verdict
Annotated Snippet
// SPDX-License-Identifier: GPL-2.0
// Copyright (c) 2020 Isovalent, Inc.
#include "vmlinux.h"
#include <bpf/bpf_helpers.h>
struct {
__uint(type, BPF_MAP_TYPE_SOCKMAP);
__uint(max_entries, 2);
__type(key, __u32);
__type(value, __u64);
} sock_map SEC(".maps");
struct {
__uint(type, BPF_MAP_TYPE_SOCKHASH);
__uint(max_entries, 2);
__type(key, __u32);
__type(value, __u64);
} sock_hash SEC(".maps");
struct {
__uint(type, BPF_MAP_TYPE_SK_STORAGE);
__uint(map_flags, BPF_F_NO_PREALLOC);
__type(key, __u32);
__type(value, __u64);
} socket_storage SEC(".maps");
static int prog_msg_verdict_common(struct sk_msg_md *msg)
{
struct task_struct *task = (struct task_struct *)bpf_get_current_task();
int verdict = SK_PASS;
__u32 pid, tpid;
__u64 *sk_stg;
pid = bpf_get_current_pid_tgid() >> 32;
sk_stg = bpf_sk_storage_get(&socket_storage, msg->sk, 0, BPF_SK_STORAGE_GET_F_CREATE);
if (!sk_stg)
return SK_DROP;
*sk_stg = pid;
bpf_probe_read_kernel(&tpid , sizeof(tpid), &task->tgid);
if (pid != tpid)
verdict = SK_DROP;
bpf_sk_storage_delete(&socket_storage, (void *)msg->sk);
return verdict;
}
SEC("sk_msg")
int prog_msg_verdict(struct sk_msg_md *msg)
{
return prog_msg_verdict_common(msg);
}
SEC("sk_msg")
int prog_msg_verdict_clone(struct sk_msg_md *msg)
{
return prog_msg_verdict_common(msg);
}
SEC("sk_msg")
int prog_msg_verdict_clone2(struct sk_msg_md *msg)
{
return prog_msg_verdict_common(msg);
}
SEC("sk_skb/stream_verdict")
int prog_skb_verdict(struct __sk_buff *skb)
{
return SK_PASS;
}
char _license[] SEC("license") = "GPL";
Annotation
- Immediate include surface: `vmlinux.h`, `bpf/bpf_helpers.h`.
- Detected declarations: `function prog_msg_verdict_common`, `function prog_msg_verdict`, `function prog_msg_verdict_clone`, `function prog_msg_verdict_clone2`, `function prog_skb_verdict`.
- Atlas domain: Support Tooling And Documentation / tools.
- Implementation status: source implementation candidate.
Implementation Notes
- This generated page is the file-by-file coverage layer; curated subsystem chapters should link here when they synthesize a multi-file control flow.
- Core OS pages should be promoted from atlas-only to deep-reviewed when they explain data structures, invariants, locking, lifecycle, and C implementation snippets.
- Driver-family pages are intentionally pattern-oriented unless they are part of the selected PCIe/NVMe representative device path.