1 #ifndef __BPF_HELPERS_H
2 #define __BPF_HELPERS_H
4 /* helper macro to place programs, maps, license in
5 * different sections in elf_bpf file. Section names
6 * are interpreted by elf_bpf loader
8 #define SEC(NAME) __attribute__((section(NAME), used))
10 /* helper functions called from eBPF programs written in C */
11 static void *(*bpf_map_lookup_elem)(void *map, void *key) =
12 (void *) BPF_FUNC_map_lookup_elem;
13 static int (*bpf_map_update_elem)(void *map, void *key, void *value,
14 unsigned long long flags) =
15 (void *) BPF_FUNC_map_update_elem;
16 static int (*bpf_map_delete_elem)(void *map, void *key) =
17 (void *) BPF_FUNC_map_delete_elem;
18 static int (*bpf_probe_read)(void *dst, int size, void *unsafe_ptr) =
19 (void *) BPF_FUNC_probe_read;
20 static unsigned long long (*bpf_ktime_get_ns)(void) =
21 (void *) BPF_FUNC_ktime_get_ns;
22 static int (*bpf_trace_printk)(const char *fmt, int fmt_size, ...) =
23 (void *) BPF_FUNC_trace_printk;
25 /* llvm builtin functions that eBPF C program may use to
26 * emit BPF_LD_ABS and BPF_LD_IND instructions
29 unsigned long long load_byte(void *skb,
30 unsigned long long off) asm("llvm.bpf.load.byte");
31 unsigned long long load_half(void *skb,
32 unsigned long long off) asm("llvm.bpf.load.half");
33 unsigned long long load_word(void *skb,
34 unsigned long long off) asm("llvm.bpf.load.word");
36 /* a helper structure used by eBPF C program
37 * to describe map attributes to elf_bpf loader
41 unsigned int key_size;
42 unsigned int value_size;
43 unsigned int max_entries;
46 static int (*bpf_skb_store_bytes)(void *ctx, int off, void *from, int len, int flags) =
47 (void *) BPF_FUNC_skb_store_bytes;
48 static int (*bpf_l3_csum_replace)(void *ctx, int off, int from, int to, int flags) =
49 (void *) BPF_FUNC_l3_csum_replace;
50 static int (*bpf_l4_csum_replace)(void *ctx, int off, int from, int to, int flags) =
51 (void *) BPF_FUNC_l4_csum_replace;