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// SPDX-License-Identifier: GPL-2.0
/* Copyright (c) 2021 Facebook */
#include <linux/bpf.h>
#include <bpf/bpf_helpers.h>
#include "bpf_misc.h"
char _license[] SEC("license") = "GPL";
struct bpf_map;
struct {
__uint(type, BPF_MAP_TYPE_ARRAY);
__type(key, __u32);
__type(value, __u32);
__uint(max_entries, 1000);
} map_random_data SEC(".maps");
struct map_bloom_type {
__uint(type, BPF_MAP_TYPE_BLOOM_FILTER);
__type(value, __u32);
__uint(max_entries, 10000);
__uint(map_extra, 5);
} map_bloom SEC(".maps");
struct {
__uint(type, BPF_MAP_TYPE_ARRAY_OF_MAPS);
__type(key, int);
__type(value, int);
__uint(max_entries, 1);
__array(values, struct map_bloom_type);
} outer_map SEC(".maps");
struct callback_ctx {
struct bpf_map *map;
};
int error = 0;
static __u64
check_elem(struct bpf_map *map, __u32 *key, __u32 *val,
struct callback_ctx *data)
{
int err;
err = bpf_map_peek_elem(data->map, val);
if (err) {
error |= 1;
return 1; /* stop the iteration */
}
return 0;
}
SEC("fentry/" SYS_PREFIX "sys_getpgid")
int inner_map(void *ctx)
{
struct bpf_map *inner_map;
struct callback_ctx data;
int key = 0;
inner_map = bpf_map_lookup_elem(&outer_map, &key);
if (!inner_map) {
error |= 2;
return 0;
}
data.map = inner_map;
bpf_for_each_map_elem(&map_random_data, check_elem, &data, 0);
return 0;
}
SEC("fentry/" SYS_PREFIX "sys_getpgid")
int check_bloom(void *ctx)
{
struct callback_ctx data;
data.map = (struct bpf_map *)&map_bloom;
bpf_for_each_map_elem(&map_random_data, check_elem, &data, 0);
return 0;
}
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