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// SPDX-License-Identifier: GPL-2.0
#include <linux/bpf.h>
#include <bpf/bpf_helpers.h>
#include "bpf_misc.h"
SEC(".maps") struct {
__uint(type, BPF_MAP_TYPE_SOCKMAP);
__uint(max_entries, 1);
__type(key, __u32);
__type(value, __u64);
} nop_map, sock_map;
SEC(".maps") struct {
__uint(type, BPF_MAP_TYPE_SOCKHASH);
__uint(max_entries, 1);
__type(key, __u32);
__type(value, __u64);
} nop_hash, sock_hash;
SEC(".maps") struct {
__uint(type, BPF_MAP_TYPE_ARRAY);
__uint(max_entries, 2);
__type(key, int);
__type(value, unsigned int);
} verdict_map;
/* Set by user space */
int redirect_type;
int redirect_flags;
#define redirect_map(__data) \
_Generic((__data), \
struct __sk_buff * : bpf_sk_redirect_map, \
struct sk_msg_md * : bpf_msg_redirect_map \
)((__data), &sock_map, (__u32){0}, redirect_flags)
#define redirect_hash(__data) \
_Generic((__data), \
struct __sk_buff * : bpf_sk_redirect_hash, \
struct sk_msg_md * : bpf_msg_redirect_hash \
)((__data), &sock_hash, &(__u32){0}, redirect_flags)
#define DEFINE_PROG(__type, __param) \
SEC("sk_" XSTR(__type)) \
int prog_ ## __type ## _verdict(__param data) \
{ \
unsigned int *count; \
int verdict; \
\
if (redirect_type == BPF_MAP_TYPE_SOCKMAP) \
verdict = redirect_map(data); \
else if (redirect_type == BPF_MAP_TYPE_SOCKHASH) \
verdict = redirect_hash(data); \
else \
verdict = redirect_type - __MAX_BPF_MAP_TYPE; \
\
count = bpf_map_lookup_elem(&verdict_map, &verdict); \
if (count) \
(*count)++; \
\
return verdict; \
}
DEFINE_PROG(skb, struct __sk_buff *);
DEFINE_PROG(msg, struct sk_msg_md *);
char _license[] SEC("license") = "GPL";
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