• Home
  • Line#
  • Scopes#
  • Navigate#
  • Raw
  • Download
1 #ifndef __BPF_HELPERS_H
2 #define __BPF_HELPERS_H
3 
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
7  */
8 #define SEC(NAME) __attribute__((section(NAME), used))
9 
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;
24 static void (*bpf_tail_call)(void *ctx, void *map, int index) =
25 	(void *) BPF_FUNC_tail_call;
26 static unsigned long long (*bpf_get_smp_processor_id)(void) =
27 	(void *) BPF_FUNC_get_smp_processor_id;
28 static unsigned long long (*bpf_get_current_pid_tgid)(void) =
29 	(void *) BPF_FUNC_get_current_pid_tgid;
30 static unsigned long long (*bpf_get_current_uid_gid)(void) =
31 	(void *) BPF_FUNC_get_current_uid_gid;
32 static int (*bpf_get_current_comm)(void *buf, int buf_size) =
33 	(void *) BPF_FUNC_get_current_comm;
34 static int (*bpf_perf_event_read)(void *map, int index) =
35 	(void *) BPF_FUNC_perf_event_read;
36 static int (*bpf_clone_redirect)(void *ctx, int ifindex, int flags) =
37 	(void *) BPF_FUNC_clone_redirect;
38 static int (*bpf_redirect)(int ifindex, int flags) =
39 	(void *) BPF_FUNC_redirect;
40 static int (*bpf_perf_event_output)(void *ctx, void *map, int index, void *data, int size) =
41 	(void *) BPF_FUNC_perf_event_output;
42 
43 /* llvm builtin functions that eBPF C program may use to
44  * emit BPF_LD_ABS and BPF_LD_IND instructions
45  */
46 struct sk_buff;
47 unsigned long long load_byte(void *skb,
48 			     unsigned long long off) asm("llvm.bpf.load.byte");
49 unsigned long long load_half(void *skb,
50 			     unsigned long long off) asm("llvm.bpf.load.half");
51 unsigned long long load_word(void *skb,
52 			     unsigned long long off) asm("llvm.bpf.load.word");
53 
54 /* a helper structure used by eBPF C program
55  * to describe map attributes to elf_bpf loader
56  */
57 struct bpf_map_def {
58 	unsigned int type;
59 	unsigned int key_size;
60 	unsigned int value_size;
61 	unsigned int max_entries;
62 };
63 
64 static int (*bpf_skb_store_bytes)(void *ctx, int off, void *from, int len, int flags) =
65 	(void *) BPF_FUNC_skb_store_bytes;
66 static int (*bpf_l3_csum_replace)(void *ctx, int off, int from, int to, int flags) =
67 	(void *) BPF_FUNC_l3_csum_replace;
68 static int (*bpf_l4_csum_replace)(void *ctx, int off, int from, int to, int flags) =
69 	(void *) BPF_FUNC_l4_csum_replace;
70 
71 #if defined(__x86_64__)
72 
73 #define PT_REGS_PARM1(x) ((x)->di)
74 #define PT_REGS_PARM2(x) ((x)->si)
75 #define PT_REGS_PARM3(x) ((x)->dx)
76 #define PT_REGS_PARM4(x) ((x)->cx)
77 #define PT_REGS_PARM5(x) ((x)->r8)
78 #define PT_REGS_RET(x) ((x)->sp)
79 #define PT_REGS_FP(x) ((x)->bp)
80 #define PT_REGS_RC(x) ((x)->ax)
81 #define PT_REGS_SP(x) ((x)->sp)
82 
83 #elif defined(__s390x__)
84 
85 #define PT_REGS_PARM1(x) ((x)->gprs[2])
86 #define PT_REGS_PARM2(x) ((x)->gprs[3])
87 #define PT_REGS_PARM3(x) ((x)->gprs[4])
88 #define PT_REGS_PARM4(x) ((x)->gprs[5])
89 #define PT_REGS_PARM5(x) ((x)->gprs[6])
90 #define PT_REGS_RET(x) ((x)->gprs[14])
91 #define PT_REGS_FP(x) ((x)->gprs[11]) /* Works only with CONFIG_FRAME_POINTER */
92 #define PT_REGS_RC(x) ((x)->gprs[2])
93 #define PT_REGS_SP(x) ((x)->gprs[15])
94 
95 #elif defined(__aarch64__)
96 
97 #define PT_REGS_PARM1(x) ((x)->regs[0])
98 #define PT_REGS_PARM2(x) ((x)->regs[1])
99 #define PT_REGS_PARM3(x) ((x)->regs[2])
100 #define PT_REGS_PARM4(x) ((x)->regs[3])
101 #define PT_REGS_PARM5(x) ((x)->regs[4])
102 #define PT_REGS_RET(x) ((x)->regs[30])
103 #define PT_REGS_FP(x) ((x)->regs[29]) /* Works only with CONFIG_FRAME_POINTER */
104 #define PT_REGS_RC(x) ((x)->regs[0])
105 #define PT_REGS_SP(x) ((x)->sp)
106 
107 #endif
108 #endif
109