linux/tools/bpf/bpftool/skeleton/pid_iter.bpf.c

82 lines
1.7 KiB
C

// SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
/* Copyright (c) 2020 Facebook */
#include <vmlinux.h>
#include <bpf/bpf_helpers.h>
#include <bpf/bpf_core_read.h>
#include <bpf/bpf_tracing.h>
#include "pid_iter.h"
/* keep in sync with the definition in main.h */
enum bpf_obj_type {
BPF_OBJ_UNKNOWN,
BPF_OBJ_PROG,
BPF_OBJ_MAP,
BPF_OBJ_LINK,
BPF_OBJ_BTF,
};
extern const void bpf_link_fops __ksym;
extern const void bpf_map_fops __ksym;
extern const void bpf_prog_fops __ksym;
extern const void btf_fops __ksym;
const volatile enum bpf_obj_type obj_type = BPF_OBJ_UNKNOWN;
static __always_inline __u32 get_obj_id(void *ent, enum bpf_obj_type type)
{
switch (type) {
case BPF_OBJ_PROG:
return BPF_CORE_READ((struct bpf_prog *)ent, aux, id);
case BPF_OBJ_MAP:
return BPF_CORE_READ((struct bpf_map *)ent, id);
case BPF_OBJ_BTF:
return BPF_CORE_READ((struct btf *)ent, id);
case BPF_OBJ_LINK:
return BPF_CORE_READ((struct bpf_link *)ent, id);
default:
return 0;
}
}
SEC("iter/task_file")
int iter(struct bpf_iter__task_file *ctx)
{
struct file *file = ctx->file;
struct task_struct *task = ctx->task;
struct pid_iter_entry e;
const void *fops;
if (!file || !task)
return 0;
switch (obj_type) {
case BPF_OBJ_PROG:
fops = &bpf_prog_fops;
break;
case BPF_OBJ_MAP:
fops = &bpf_map_fops;
break;
case BPF_OBJ_BTF:
fops = &btf_fops;
break;
case BPF_OBJ_LINK:
fops = &bpf_link_fops;
break;
default:
return 0;
}
if (file->f_op != fops)
return 0;
e.pid = task->tgid;
e.id = get_obj_id(file->private_data, obj_type);
bpf_probe_read_kernel(&e.comm, sizeof(e.comm),
task->group_leader->comm);
bpf_seq_write(ctx->meta->seq, &e, sizeof(e));
return 0;
}
char LICENSE[] SEC("license") = "Dual BSD/GPL";