1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * Linux Socket Filter Data Structures
4 */
5#ifndef __TOOLS_LINUX_FILTER_H
6#define __TOOLS_LINUX_FILTER_H
7
8#include <linux/bpf.h>
9
10/* ArgX, context and stack frame pointer register positions. Note,
11 * Arg1, Arg2, Arg3, etc are used as argument mappings of function
12 * calls in BPF_CALL instruction.
13 */
14#define BPF_REG_ARG1	BPF_REG_1
15#define BPF_REG_ARG2	BPF_REG_2
16#define BPF_REG_ARG3	BPF_REG_3
17#define BPF_REG_ARG4	BPF_REG_4
18#define BPF_REG_ARG5	BPF_REG_5
19#define BPF_REG_CTX	BPF_REG_6
20#define BPF_REG_FP	BPF_REG_10
21
22/* Additional register mappings for converted user programs. */
23#define BPF_REG_A	BPF_REG_0
24#define BPF_REG_X	BPF_REG_7
25#define BPF_REG_TMP	BPF_REG_8
26
27/* BPF program can access up to 512 bytes of stack space. */
28#define MAX_BPF_STACK	512
29
30/* Helper macros for filter block array initializers. */
31
32/* ALU ops on registers, bpf_add|sub|...: dst_reg += src_reg */
33
34#define BPF_ALU64_REG(OP, DST, SRC)				\
35	((struct bpf_insn) {					\
36		.code  = BPF_ALU64 | BPF_OP(OP) | BPF_X,	\
37		.dst_reg = DST,					\
38		.src_reg = SRC,					\
39		.off   = 0,					\
40		.imm   = 0 })
41
42#define BPF_ALU32_REG(OP, DST, SRC)				\
43	((struct bpf_insn) {					\
44		.code  = BPF_ALU | BPF_OP(OP) | BPF_X,		\
45		.dst_reg = DST,					\
46		.src_reg = SRC,					\
47		.off   = 0,					\
48		.imm   = 0 })
49
50/* ALU ops on immediates, bpf_add|sub|...: dst_reg += imm32 */
51
52#define BPF_ALU64_IMM(OP, DST, IMM)				\
53	((struct bpf_insn) {					\
54		.code  = BPF_ALU64 | BPF_OP(OP) | BPF_K,	\
55		.dst_reg = DST,					\
56		.src_reg = 0,					\
57		.off   = 0,					\
58		.imm   = IMM })
59
60#define BPF_ALU32_IMM(OP, DST, IMM)				\
61	((struct bpf_insn) {					\
62		.code  = BPF_ALU | BPF_OP(OP) | BPF_K,		\
63		.dst_reg = DST,					\
64		.src_reg = 0,					\
65		.off   = 0,					\
66		.imm   = IMM })
67
68/* Endianess conversion, cpu_to_{l,b}e(), {l,b}e_to_cpu() */
69
70#define BPF_ENDIAN(TYPE, DST, LEN)				\
71	((struct bpf_insn) {					\
72		.code  = BPF_ALU | BPF_END | BPF_SRC(TYPE),	\
73		.dst_reg = DST,					\
74		.src_reg = 0,					\
75		.off   = 0,					\
76		.imm   = LEN })
77
78/* Short form of mov, dst_reg = src_reg */
79
80#define BPF_MOV64_REG(DST, SRC)					\
81	((struct bpf_insn) {					\
82		.code  = BPF_ALU64 | BPF_MOV | BPF_X,		\
83		.dst_reg = DST,					\
84		.src_reg = SRC,					\
85		.off   = 0,					\
86		.imm   = 0 })
87
88#define BPF_MOV32_REG(DST, SRC)					\
89	((struct bpf_insn) {					\
90		.code  = BPF_ALU | BPF_MOV | BPF_X,		\
91		.dst_reg = DST,					\
92		.src_reg = SRC,					\
93		.off   = 0,					\
94		.imm   = 0 })
95
96/* Short form of mov, dst_reg = imm32 */
97
98#define BPF_MOV64_IMM(DST, IMM)					\
99	((struct bpf_insn) {					\
100		.code  = BPF_ALU64 | BPF_MOV | BPF_K,		\
101		.dst_reg = DST,					\
102		.src_reg = 0,					\
103		.off   = 0,					\
104		.imm   = IMM })
105
106#define BPF_MOV32_IMM(DST, IMM)					\
107	((struct bpf_insn) {					\
108		.code  = BPF_ALU | BPF_MOV | BPF_K,		\
109		.dst_reg = DST,					\
110		.src_reg = 0,					\
111		.off   = 0,					\
112		.imm   = IMM })
113
114/* Short form of mov based on type,  BPF_X: dst_reg = src_reg, BPF_K: dst_reg = imm32 */
115
116#define BPF_MOV64_RAW(TYPE, DST, SRC, IMM)			\
117	((struct bpf_insn) {					\
118		.code  = BPF_ALU64 | BPF_MOV | BPF_SRC(TYPE),	\
119		.dst_reg = DST,					\
120		.src_reg = SRC,					\
121		.off   = 0,					\
122		.imm   = IMM })
123
124#define BPF_MOV32_RAW(TYPE, DST, SRC, IMM)			\
125	((struct bpf_insn) {					\
126		.code  = BPF_ALU | BPF_MOV | BPF_SRC(TYPE),	\
127		.dst_reg = DST,					\
128		.src_reg = SRC,					\
129		.off   = 0,					\
130		.imm   = IMM })
131
132/* Direct packet access, R0 = *(uint *) (skb->data + imm32) */
133
134#define BPF_LD_ABS(SIZE, IMM)					\
135	((struct bpf_insn) {					\
136		.code  = BPF_LD | BPF_SIZE(SIZE) | BPF_ABS,	\
137		.dst_reg = 0,					\
138		.src_reg = 0,					\
139		.off   = 0,					\
140		.imm   = IMM })
141
142/* Indirect packet access, R0 = *(uint *) (skb->data + src_reg + imm32) */
143
144#define BPF_LD_IND(SIZE, SRC, IMM)				\
145	((struct bpf_insn) {					\
146		.code  = BPF_LD | BPF_SIZE(SIZE) | BPF_IND,	\
147		.dst_reg = 0,					\
148		.src_reg = SRC,					\
149		.off   = 0,					\
150		.imm   = IMM })
151
152/* Memory load, dst_reg = *(uint *) (src_reg + off16) */
153
154#define BPF_LDX_MEM(SIZE, DST, SRC, OFF)			\
155	((struct bpf_insn) {					\
156		.code  = BPF_LDX | BPF_SIZE(SIZE) | BPF_MEM,	\
157		.dst_reg = DST,					\
158		.src_reg = SRC,					\
159		.off   = OFF,					\
160		.imm   = 0 })
161
162/* Memory store, *(uint *) (dst_reg + off16) = src_reg */
163
164#define BPF_STX_MEM(SIZE, DST, SRC, OFF)			\
165	((struct bpf_insn) {					\
166		.code  = BPF_STX | BPF_SIZE(SIZE) | BPF_MEM,	\
167		.dst_reg = DST,					\
168		.src_reg = SRC,					\
169		.off   = OFF,					\
170		.imm   = 0 })
171
172/*
173 * Atomic operations:
174 *
175 *   BPF_ADD                  *(uint *) (dst_reg + off16) += src_reg
176 *   BPF_AND                  *(uint *) (dst_reg + off16) &= src_reg
177 *   BPF_OR                   *(uint *) (dst_reg + off16) |= src_reg
178 *   BPF_XOR                  *(uint *) (dst_reg + off16) ^= src_reg
179 *   BPF_ADD | BPF_FETCH      src_reg = atomic_fetch_add(dst_reg + off16, src_reg);
180 *   BPF_AND | BPF_FETCH      src_reg = atomic_fetch_and(dst_reg + off16, src_reg);
181 *   BPF_OR | BPF_FETCH       src_reg = atomic_fetch_or(dst_reg + off16, src_reg);
182 *   BPF_XOR | BPF_FETCH      src_reg = atomic_fetch_xor(dst_reg + off16, src_reg);
183 *   BPF_XCHG                 src_reg = atomic_xchg(dst_reg + off16, src_reg)
184 *   BPF_CMPXCHG              r0 = atomic_cmpxchg(dst_reg + off16, r0, src_reg)
185 */
186
187#define BPF_ATOMIC_OP(SIZE, OP, DST, SRC, OFF)			\
188	((struct bpf_insn) {					\
189		.code  = BPF_STX | BPF_SIZE(SIZE) | BPF_ATOMIC,	\
190		.dst_reg = DST,					\
191		.src_reg = SRC,					\
192		.off   = OFF,					\
193		.imm   = OP })
194
195/* Legacy alias */
196#define BPF_STX_XADD(SIZE, DST, SRC, OFF) BPF_ATOMIC_OP(SIZE, BPF_ADD, DST, SRC, OFF)
197
198/* Memory store, *(uint *) (dst_reg + off16) = imm32 */
199
200#define BPF_ST_MEM(SIZE, DST, OFF, IMM)				\
201	((struct bpf_insn) {					\
202		.code  = BPF_ST | BPF_SIZE(SIZE) | BPF_MEM,	\
203		.dst_reg = DST,					\
204		.src_reg = 0,					\
205		.off   = OFF,					\
206		.imm   = IMM })
207
208/* Conditional jumps against registers, if (dst_reg 'op' src_reg) goto pc + off16 */
209
210#define BPF_JMP_REG(OP, DST, SRC, OFF)				\
211	((struct bpf_insn) {					\
212		.code  = BPF_JMP | BPF_OP(OP) | BPF_X,		\
213		.dst_reg = DST,					\
214		.src_reg = SRC,					\
215		.off   = OFF,					\
216		.imm   = 0 })
217
218/* Like BPF_JMP_REG, but with 32-bit wide operands for comparison. */
219
220#define BPF_JMP32_REG(OP, DST, SRC, OFF)			\
221	((struct bpf_insn) {					\
222		.code  = BPF_JMP32 | BPF_OP(OP) | BPF_X,	\
223		.dst_reg = DST,					\
224		.src_reg = SRC,					\
225		.off   = OFF,					\
226		.imm   = 0 })
227
228/* Conditional jumps against immediates, if (dst_reg 'op' imm32) goto pc + off16 */
229
230#define BPF_JMP_IMM(OP, DST, IMM, OFF)				\
231	((struct bpf_insn) {					\
232		.code  = BPF_JMP | BPF_OP(OP) | BPF_K,		\
233		.dst_reg = DST,					\
234		.src_reg = 0,					\
235		.off   = OFF,					\
236		.imm   = IMM })
237
238/* Like BPF_JMP_IMM, but with 32-bit wide operands for comparison. */
239
240#define BPF_JMP32_IMM(OP, DST, IMM, OFF)			\
241	((struct bpf_insn) {					\
242		.code  = BPF_JMP32 | BPF_OP(OP) | BPF_K,	\
243		.dst_reg = DST,					\
244		.src_reg = 0,					\
245		.off   = OFF,					\
246		.imm   = IMM })
247
248/* Unconditional jumps, goto pc + off16 */
249
250#define BPF_JMP_A(OFF)						\
251	((struct bpf_insn) {					\
252		.code  = BPF_JMP | BPF_JA,			\
253		.dst_reg = 0,					\
254		.src_reg = 0,					\
255		.off   = OFF,					\
256		.imm   = 0 })
257
258/* Function call */
259
260#define BPF_EMIT_CALL(FUNC)					\
261	((struct bpf_insn) {					\
262		.code  = BPF_JMP | BPF_CALL,			\
263		.dst_reg = 0,					\
264		.src_reg = 0,					\
265		.off   = 0,					\
266		.imm   = ((FUNC) - BPF_FUNC_unspec) })
267
268/* Raw code statement block */
269
270#define BPF_RAW_INSN(CODE, DST, SRC, OFF, IMM)			\
271	((struct bpf_insn) {					\
272		.code  = CODE,					\
273		.dst_reg = DST,					\
274		.src_reg = SRC,					\
275		.off   = OFF,					\
276		.imm   = IMM })
277
278/* BPF_LD_IMM64 macro encodes single 'load 64-bit immediate' insn */
279
280#define BPF_LD_IMM64(DST, IMM)					\
281	BPF_LD_IMM64_RAW(DST, 0, IMM)
282
283#define BPF_LD_IMM64_RAW(DST, SRC, IMM)				\
284	((struct bpf_insn) {					\
285		.code  = BPF_LD | BPF_DW | BPF_IMM,		\
286		.dst_reg = DST,					\
287		.src_reg = SRC,					\
288		.off   = 0,					\
289		.imm   = (__u32) (IMM) }),			\
290	((struct bpf_insn) {					\
291		.code  = 0, /* zero is reserved opcode */	\
292		.dst_reg = 0,					\
293		.src_reg = 0,					\
294		.off   = 0,					\
295		.imm   = ((__u64) (IMM)) >> 32 })
296
297#define BPF_LD_IMM64_RAW_FULL(DST, SRC, OFF1, OFF2, IMM1, IMM2)	\
298	((struct bpf_insn) {					\
299		.code  = BPF_LD | BPF_DW | BPF_IMM,		\
300		.dst_reg = DST,					\
301		.src_reg = SRC,					\
302		.off   = OFF1,					\
303		.imm   = IMM1 }),				\
304	((struct bpf_insn) {					\
305		.code  = 0, /* zero is reserved opcode */	\
306		.dst_reg = 0,					\
307		.src_reg = 0,					\
308		.off   = OFF2,					\
309		.imm   = IMM2 })
310
311/* pseudo BPF_LD_IMM64 insn used to refer to process-local map_fd */
312
313#define BPF_LD_MAP_FD(DST, MAP_FD)				\
314	BPF_LD_IMM64_RAW_FULL(DST, BPF_PSEUDO_MAP_FD, 0, 0,	\
315			      MAP_FD, 0)
316
317#define BPF_LD_MAP_VALUE(DST, MAP_FD, VALUE_OFF)		\
318	BPF_LD_IMM64_RAW_FULL(DST, BPF_PSEUDO_MAP_VALUE, 0, 0,	\
319			      MAP_FD, VALUE_OFF)
320
321/* Relative call */
322
323#define BPF_CALL_REL(TGT)					\
324	((struct bpf_insn) {					\
325		.code  = BPF_JMP | BPF_CALL,			\
326		.dst_reg = 0,					\
327		.src_reg = BPF_PSEUDO_CALL,			\
328		.off   = 0,					\
329		.imm   = TGT })
330
331/* Program exit */
332
333#define BPF_EXIT_INSN()						\
334	((struct bpf_insn) {					\
335		.code  = BPF_JMP | BPF_EXIT,			\
336		.dst_reg = 0,					\
337		.src_reg = 0,					\
338		.off   = 0,					\
339		.imm   = 0 })
340
341#endif /* __TOOLS_LINUX_FILTER_H */
342