4 * This program is free software; you can distribute it and/or modify
5 * it under the terms of the GNU General Public License as published
6 * by the Free Software Foundation; either version 2 of the License,
7 * or (at your option) any later version.
9 * Syntax kept close to:
11 * Steven McCanne and Van Jacobson. 1993. The BSD packet filter: a new
12 * architecture for user-level packet capture. In Proceedings of the
13 * USENIX Winter 1993 Conference Proceedings on USENIX Winter 1993
14 * Conference Proceedings (USENIX'93). USENIX Association, Berkeley,
17 * Copyright 2013 Daniel Borkmann <borkmann@redhat.com>
18 * Licensed under the GNU General Public License, version 2.0 (GPLv2)
31 #include <linux/filter.h>
33 #include "bpf_exp.yacc.h"
35 enum jmp_type
{ JTL
, JFL
, JKL
};
38 extern
int yylex(void);
39 extern
void yyerror(const char *str
);
41 extern
void bpf_asm_compile
(FILE *fp
, bool cstyle
);
42 static void bpf_set_curr_instr
(uint16_t op
, uint8_t jt
, uint8_t jf
, uint32_t k
);
43 static void bpf_set_curr_label
(char *label
);
44 static void bpf_set_jmp_label
(char *label
, enum jmp_type type
);
53 %token OP_LDB OP_LDH OP_LD OP_LDX OP_ST OP_STX OP_JMP OP_JEQ OP_JGT OP_JGE
54 %token OP_JSET OP_ADD OP_SUB OP_MUL OP_DIV OP_AND OP_OR OP_XOR OP_LSH OP_RSH
55 %token OP_RET OP_TAX OP_TXA OP_LDXB OP_MOD OP_NEG OP_JNEQ OP_JLT OP_JLE OP_LDI
58 %token K_PKT_LEN K_PROTO K_TYPE K_NLATTR K_NLATTR_NEST K_MARK K_QUEUE K_HATYPE
59 %token K_RXHASH K_CPU K_IFIDX K_VLAN_TCI K_VLAN_AVAIL K_VLAN_TPID K_POFF K_RAND
61 %token
':' ',' '[' ']' '(' ')' 'x' 'a' '+' 'M' '*' '&' '#' '%'
118 : label
':' { bpf_set_curr_label
($1); }
122 : OP_LDB
'[' 'x' '+' number
']' {
123 bpf_set_curr_instr
(BPF_LD | BPF_B | BPF_IND
, 0, 0, $5); }
124 | OP_LDB
'[' '%' 'x' '+' number
']' {
125 bpf_set_curr_instr
(BPF_LD | BPF_B | BPF_IND
, 0, 0, $6); }
126 | OP_LDB
'[' number
']' {
127 bpf_set_curr_instr
(BPF_LD | BPF_B | BPF_ABS
, 0, 0, $3); }
129 bpf_set_curr_instr
(BPF_LD | BPF_B | BPF_ABS
, 0, 0,
130 SKF_AD_OFF
+ SKF_AD_PROTOCOL
); }
132 bpf_set_curr_instr
(BPF_LD | BPF_B | BPF_ABS
, 0, 0,
133 SKF_AD_OFF
+ SKF_AD_PKTTYPE
); }
135 bpf_set_curr_instr
(BPF_LD | BPF_B | BPF_ABS
, 0, 0,
136 SKF_AD_OFF
+ SKF_AD_IFINDEX
); }
138 bpf_set_curr_instr
(BPF_LD | BPF_B | BPF_ABS
, 0, 0,
139 SKF_AD_OFF
+ SKF_AD_NLATTR
); }
140 | OP_LDB K_NLATTR_NEST
{
141 bpf_set_curr_instr
(BPF_LD | BPF_B | BPF_ABS
, 0, 0,
142 SKF_AD_OFF
+ SKF_AD_NLATTR_NEST
); }
144 bpf_set_curr_instr
(BPF_LD | BPF_B | BPF_ABS
, 0, 0,
145 SKF_AD_OFF
+ SKF_AD_MARK
); }
147 bpf_set_curr_instr
(BPF_LD | BPF_B | BPF_ABS
, 0, 0,
148 SKF_AD_OFF
+ SKF_AD_QUEUE
); }
150 bpf_set_curr_instr
(BPF_LD | BPF_B | BPF_ABS
, 0, 0,
151 SKF_AD_OFF
+ SKF_AD_HATYPE
); }
153 bpf_set_curr_instr
(BPF_LD | BPF_B | BPF_ABS
, 0, 0,
154 SKF_AD_OFF
+ SKF_AD_RXHASH
); }
156 bpf_set_curr_instr
(BPF_LD | BPF_B | BPF_ABS
, 0, 0,
157 SKF_AD_OFF
+ SKF_AD_CPU
); }
158 | OP_LDB K_VLAN_TCI
{
159 bpf_set_curr_instr
(BPF_LD | BPF_B | BPF_ABS
, 0, 0,
160 SKF_AD_OFF
+ SKF_AD_VLAN_TAG
); }
161 | OP_LDB K_VLAN_AVAIL
{
162 bpf_set_curr_instr
(BPF_LD | BPF_B | BPF_ABS
, 0, 0,
163 SKF_AD_OFF
+ SKF_AD_VLAN_TAG_PRESENT
); }
165 bpf_set_curr_instr
(BPF_LD | BPF_B | BPF_ABS
, 0, 0,
166 SKF_AD_OFF
+ SKF_AD_PAY_OFFSET
); }
168 bpf_set_curr_instr
(BPF_LD | BPF_B | BPF_ABS
, 0, 0,
169 SKF_AD_OFF
+ SKF_AD_RANDOM
); }
170 | OP_LDB K_VLAN_TPID
{
171 bpf_set_curr_instr
(BPF_LD | BPF_B | BPF_ABS
, 0, 0,
172 SKF_AD_OFF
+ SKF_AD_VLAN_TPID
); }
176 : OP_LDH
'[' 'x' '+' number
']' {
177 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_IND
, 0, 0, $5); }
178 | OP_LDH
'[' '%' 'x' '+' number
']' {
179 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_IND
, 0, 0, $6); }
180 | OP_LDH
'[' number
']' {
181 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0, $3); }
183 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
184 SKF_AD_OFF
+ SKF_AD_PROTOCOL
); }
186 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
187 SKF_AD_OFF
+ SKF_AD_PKTTYPE
); }
189 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
190 SKF_AD_OFF
+ SKF_AD_IFINDEX
); }
192 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
193 SKF_AD_OFF
+ SKF_AD_NLATTR
); }
194 | OP_LDH K_NLATTR_NEST
{
195 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
196 SKF_AD_OFF
+ SKF_AD_NLATTR_NEST
); }
198 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
199 SKF_AD_OFF
+ SKF_AD_MARK
); }
201 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
202 SKF_AD_OFF
+ SKF_AD_QUEUE
); }
204 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
205 SKF_AD_OFF
+ SKF_AD_HATYPE
); }
207 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
208 SKF_AD_OFF
+ SKF_AD_RXHASH
); }
210 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
211 SKF_AD_OFF
+ SKF_AD_CPU
); }
212 | OP_LDH K_VLAN_TCI
{
213 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
214 SKF_AD_OFF
+ SKF_AD_VLAN_TAG
); }
215 | OP_LDH K_VLAN_AVAIL
{
216 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
217 SKF_AD_OFF
+ SKF_AD_VLAN_TAG_PRESENT
); }
219 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
220 SKF_AD_OFF
+ SKF_AD_PAY_OFFSET
); }
222 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
223 SKF_AD_OFF
+ SKF_AD_RANDOM
); }
224 | OP_LDH K_VLAN_TPID
{
225 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
226 SKF_AD_OFF
+ SKF_AD_VLAN_TPID
); }
230 : OP_LDI
'#' number
{
231 bpf_set_curr_instr
(BPF_LD | BPF_IMM
, 0, 0, $3); }
233 bpf_set_curr_instr
(BPF_LD | BPF_IMM
, 0, 0, $2); }
238 bpf_set_curr_instr
(BPF_LD | BPF_IMM
, 0, 0, $3); }
240 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_LEN
, 0, 0, 0); }
242 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
243 SKF_AD_OFF
+ SKF_AD_PROTOCOL
); }
245 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
246 SKF_AD_OFF
+ SKF_AD_PKTTYPE
); }
248 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
249 SKF_AD_OFF
+ SKF_AD_IFINDEX
); }
251 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
252 SKF_AD_OFF
+ SKF_AD_NLATTR
); }
253 | OP_LD K_NLATTR_NEST
{
254 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
255 SKF_AD_OFF
+ SKF_AD_NLATTR_NEST
); }
257 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
258 SKF_AD_OFF
+ SKF_AD_MARK
); }
260 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
261 SKF_AD_OFF
+ SKF_AD_QUEUE
); }
263 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
264 SKF_AD_OFF
+ SKF_AD_HATYPE
); }
266 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
267 SKF_AD_OFF
+ SKF_AD_RXHASH
); }
269 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
270 SKF_AD_OFF
+ SKF_AD_CPU
); }
272 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
273 SKF_AD_OFF
+ SKF_AD_VLAN_TAG
); }
274 | OP_LD K_VLAN_AVAIL
{
275 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
276 SKF_AD_OFF
+ SKF_AD_VLAN_TAG_PRESENT
); }
278 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
279 SKF_AD_OFF
+ SKF_AD_PAY_OFFSET
); }
281 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
282 SKF_AD_OFF
+ SKF_AD_RANDOM
); }
283 | OP_LD K_VLAN_TPID
{
284 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
285 SKF_AD_OFF
+ SKF_AD_VLAN_TPID
); }
286 | OP_LD
'M' '[' number
']' {
287 bpf_set_curr_instr
(BPF_LD | BPF_MEM
, 0, 0, $4); }
288 | OP_LD
'[' 'x' '+' number
']' {
289 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_IND
, 0, 0, $5); }
290 | OP_LD
'[' '%' 'x' '+' number
']' {
291 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_IND
, 0, 0, $6); }
292 | OP_LD
'[' number
']' {
293 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0, $3); }
297 : OP_LDXI
'#' number
{
298 bpf_set_curr_instr
(BPF_LDX | BPF_IMM
, 0, 0, $3); }
300 bpf_set_curr_instr
(BPF_LDX | BPF_IMM
, 0, 0, $2); }
304 : OP_LDX
'#' number
{
305 bpf_set_curr_instr
(BPF_LDX | BPF_IMM
, 0, 0, $3); }
307 bpf_set_curr_instr
(BPF_LDX | BPF_W | BPF_LEN
, 0, 0, 0); }
308 | OP_LDX
'M' '[' number
']' {
309 bpf_set_curr_instr
(BPF_LDX | BPF_MEM
, 0, 0, $4); }
310 | OP_LDXB number
'*' '(' '[' number
']' '&' number
')' {
311 if
($2 != 4 ||
$9 != 0xf) {
312 fprintf
(stderr
, "ldxb offset not supported!\n");
315 bpf_set_curr_instr
(BPF_LDX | BPF_MSH | BPF_B
, 0, 0, $6); } }
316 | OP_LDX number
'*' '(' '[' number
']' '&' number
')' {
317 if
($2 != 4 ||
$9 != 0xf) {
318 fprintf
(stderr
, "ldxb offset not supported!\n");
321 bpf_set_curr_instr
(BPF_LDX | BPF_MSH | BPF_B
, 0, 0, $6); } }
325 : OP_ST
'M' '[' number
']' {
326 bpf_set_curr_instr
(BPF_ST
, 0, 0, $4); }
330 : OP_STX
'M' '[' number
']' {
331 bpf_set_curr_instr
(BPF_STX
, 0, 0, $4); }
336 bpf_set_jmp_label
($2, JKL
);
337 bpf_set_curr_instr
(BPF_JMP | BPF_JA
, 0, 0, 0); }
341 : OP_JEQ
'#' number
',' label
',' label
{
342 bpf_set_jmp_label
($5, JTL
);
343 bpf_set_jmp_label
($7, JFL
);
344 bpf_set_curr_instr
(BPF_JMP | BPF_JEQ | BPF_K
, 0, 0, $3); }
345 | OP_JEQ
'x' ',' label
',' label
{
346 bpf_set_jmp_label
($4, JTL
);
347 bpf_set_jmp_label
($6, JFL
);
348 bpf_set_curr_instr
(BPF_JMP | BPF_JEQ | BPF_X
, 0, 0, 0); }
349 | OP_JEQ
'%' 'x' ',' label
',' label
{
350 bpf_set_jmp_label
($5, JTL
);
351 bpf_set_jmp_label
($7, JFL
);
352 bpf_set_curr_instr
(BPF_JMP | BPF_JEQ | BPF_X
, 0, 0, 0); }
353 | OP_JEQ
'#' number
',' label
{
354 bpf_set_jmp_label
($5, JTL
);
355 bpf_set_curr_instr
(BPF_JMP | BPF_JEQ | BPF_K
, 0, 0, $3); }
356 | OP_JEQ
'x' ',' label
{
357 bpf_set_jmp_label
($4, JTL
);
358 bpf_set_curr_instr
(BPF_JMP | BPF_JEQ | BPF_X
, 0, 0, 0); }
359 | OP_JEQ
'%' 'x' ',' label
{
360 bpf_set_jmp_label
($5, JTL
);
361 bpf_set_curr_instr
(BPF_JMP | BPF_JEQ | BPF_X
, 0, 0, 0); }
365 : OP_JNEQ
'#' number
',' label
{
366 bpf_set_jmp_label
($5, JFL
);
367 bpf_set_curr_instr
(BPF_JMP | BPF_JEQ | BPF_K
, 0, 0, $3); }
368 | OP_JNEQ
'x' ',' label
{
369 bpf_set_jmp_label
($4, JFL
);
370 bpf_set_curr_instr
(BPF_JMP | BPF_JEQ | BPF_X
, 0, 0, 0); }
371 | OP_JNEQ
'%' 'x' ',' label
{
372 bpf_set_jmp_label
($5, JFL
);
373 bpf_set_curr_instr
(BPF_JMP | BPF_JEQ | BPF_X
, 0, 0, 0); }
377 : OP_JLT
'#' number
',' label
{
378 bpf_set_jmp_label
($5, JFL
);
379 bpf_set_curr_instr
(BPF_JMP | BPF_JGE | BPF_K
, 0, 0, $3); }
380 | OP_JLT
'x' ',' label
{
381 bpf_set_jmp_label
($4, JFL
);
382 bpf_set_curr_instr
(BPF_JMP | BPF_JGE | BPF_X
, 0, 0, 0); }
383 | OP_JLT
'%' 'x' ',' label
{
384 bpf_set_jmp_label
($5, JFL
);
385 bpf_set_curr_instr
(BPF_JMP | BPF_JGE | BPF_X
, 0, 0, 0); }
389 : OP_JLE
'#' number
',' label
{
390 bpf_set_jmp_label
($5, JFL
);
391 bpf_set_curr_instr
(BPF_JMP | BPF_JGT | BPF_K
, 0, 0, $3); }
392 | OP_JLE
'x' ',' label
{
393 bpf_set_jmp_label
($4, JFL
);
394 bpf_set_curr_instr
(BPF_JMP | BPF_JGT | BPF_X
, 0, 0, 0); }
395 | OP_JLE
'%' 'x' ',' label
{
396 bpf_set_jmp_label
($5, JFL
);
397 bpf_set_curr_instr
(BPF_JMP | BPF_JGT | BPF_X
, 0, 0, 0); }
401 : OP_JGT
'#' number
',' label
',' label
{
402 bpf_set_jmp_label
($5, JTL
);
403 bpf_set_jmp_label
($7, JFL
);
404 bpf_set_curr_instr
(BPF_JMP | BPF_JGT | BPF_K
, 0, 0, $3); }
405 | OP_JGT
'x' ',' label
',' label
{
406 bpf_set_jmp_label
($4, JTL
);
407 bpf_set_jmp_label
($6, JFL
);
408 bpf_set_curr_instr
(BPF_JMP | BPF_JGT | BPF_X
, 0, 0, 0); }
409 | OP_JGT
'%' 'x' ',' label
',' label
{
410 bpf_set_jmp_label
($5, JTL
);
411 bpf_set_jmp_label
($7, JFL
);
412 bpf_set_curr_instr
(BPF_JMP | BPF_JGT | BPF_X
, 0, 0, 0); }
413 | OP_JGT
'#' number
',' label
{
414 bpf_set_jmp_label
($5, JTL
);
415 bpf_set_curr_instr
(BPF_JMP | BPF_JGT | BPF_K
, 0, 0, $3); }
416 | OP_JGT
'x' ',' label
{
417 bpf_set_jmp_label
($4, JTL
);
418 bpf_set_curr_instr
(BPF_JMP | BPF_JGT | BPF_X
, 0, 0, 0); }
419 | OP_JGT
'%' 'x' ',' label
{
420 bpf_set_jmp_label
($5, JTL
);
421 bpf_set_curr_instr
(BPF_JMP | BPF_JGT | BPF_X
, 0, 0, 0); }
425 : OP_JGE
'#' number
',' label
',' label
{
426 bpf_set_jmp_label
($5, JTL
);
427 bpf_set_jmp_label
($7, JFL
);
428 bpf_set_curr_instr
(BPF_JMP | BPF_JGE | BPF_K
, 0, 0, $3); }
429 | OP_JGE
'x' ',' label
',' label
{
430 bpf_set_jmp_label
($4, JTL
);
431 bpf_set_jmp_label
($6, JFL
);
432 bpf_set_curr_instr
(BPF_JMP | BPF_JGE | BPF_X
, 0, 0, 0); }
433 | OP_JGE
'%' 'x' ',' label
',' label
{
434 bpf_set_jmp_label
($5, JTL
);
435 bpf_set_jmp_label
($7, JFL
);
436 bpf_set_curr_instr
(BPF_JMP | BPF_JGE | BPF_X
, 0, 0, 0); }
437 | OP_JGE
'#' number
',' label
{
438 bpf_set_jmp_label
($5, JTL
);
439 bpf_set_curr_instr
(BPF_JMP | BPF_JGE | BPF_K
, 0, 0, $3); }
440 | OP_JGE
'x' ',' label
{
441 bpf_set_jmp_label
($4, JTL
);
442 bpf_set_curr_instr
(BPF_JMP | BPF_JGE | BPF_X
, 0, 0, 0); }
443 | OP_JGE
'%' 'x' ',' label
{
444 bpf_set_jmp_label
($5, JTL
);
445 bpf_set_curr_instr
(BPF_JMP | BPF_JGE | BPF_X
, 0, 0, 0); }
449 : OP_JSET
'#' number
',' label
',' label
{
450 bpf_set_jmp_label
($5, JTL
);
451 bpf_set_jmp_label
($7, JFL
);
452 bpf_set_curr_instr
(BPF_JMP | BPF_JSET | BPF_K
, 0, 0, $3); }
453 | OP_JSET
'x' ',' label
',' label
{
454 bpf_set_jmp_label
($4, JTL
);
455 bpf_set_jmp_label
($6, JFL
);
456 bpf_set_curr_instr
(BPF_JMP | BPF_JSET | BPF_X
, 0, 0, 0); }
457 | OP_JSET
'%' 'x' ',' label
',' label
{
458 bpf_set_jmp_label
($5, JTL
);
459 bpf_set_jmp_label
($7, JFL
);
460 bpf_set_curr_instr
(BPF_JMP | BPF_JSET | BPF_X
, 0, 0, 0); }
461 | OP_JSET
'#' number
',' label
{
462 bpf_set_jmp_label
($5, JTL
);
463 bpf_set_curr_instr
(BPF_JMP | BPF_JSET | BPF_K
, 0, 0, $3); }
464 | OP_JSET
'x' ',' label
{
465 bpf_set_jmp_label
($4, JTL
);
466 bpf_set_curr_instr
(BPF_JMP | BPF_JSET | BPF_X
, 0, 0, 0); }
467 | OP_JSET
'%' 'x' ',' label
{
468 bpf_set_jmp_label
($5, JTL
);
469 bpf_set_curr_instr
(BPF_JMP | BPF_JSET | BPF_X
, 0, 0, 0); }
473 : OP_ADD
'#' number
{
474 bpf_set_curr_instr
(BPF_ALU | BPF_ADD | BPF_K
, 0, 0, $3); }
476 bpf_set_curr_instr
(BPF_ALU | BPF_ADD | BPF_X
, 0, 0, 0); }
478 bpf_set_curr_instr
(BPF_ALU | BPF_ADD | BPF_X
, 0, 0, 0); }
482 : OP_SUB
'#' number
{
483 bpf_set_curr_instr
(BPF_ALU | BPF_SUB | BPF_K
, 0, 0, $3); }
485 bpf_set_curr_instr
(BPF_ALU | BPF_SUB | BPF_X
, 0, 0, 0); }
487 bpf_set_curr_instr
(BPF_ALU | BPF_SUB | BPF_X
, 0, 0, 0); }
491 : OP_MUL
'#' number
{
492 bpf_set_curr_instr
(BPF_ALU | BPF_MUL | BPF_K
, 0, 0, $3); }
494 bpf_set_curr_instr
(BPF_ALU | BPF_MUL | BPF_X
, 0, 0, 0); }
496 bpf_set_curr_instr
(BPF_ALU | BPF_MUL | BPF_X
, 0, 0, 0); }
500 : OP_DIV
'#' number
{
501 bpf_set_curr_instr
(BPF_ALU | BPF_DIV | BPF_K
, 0, 0, $3); }
503 bpf_set_curr_instr
(BPF_ALU | BPF_DIV | BPF_X
, 0, 0, 0); }
505 bpf_set_curr_instr
(BPF_ALU | BPF_DIV | BPF_X
, 0, 0, 0); }
509 : OP_MOD
'#' number
{
510 bpf_set_curr_instr
(BPF_ALU | BPF_MOD | BPF_K
, 0, 0, $3); }
512 bpf_set_curr_instr
(BPF_ALU | BPF_MOD | BPF_X
, 0, 0, 0); }
514 bpf_set_curr_instr
(BPF_ALU | BPF_MOD | BPF_X
, 0, 0, 0); }
519 bpf_set_curr_instr
(BPF_ALU | BPF_NEG
, 0, 0, 0); }
523 : OP_AND
'#' number
{
524 bpf_set_curr_instr
(BPF_ALU | BPF_AND | BPF_K
, 0, 0, $3); }
526 bpf_set_curr_instr
(BPF_ALU | BPF_AND | BPF_X
, 0, 0, 0); }
528 bpf_set_curr_instr
(BPF_ALU | BPF_AND | BPF_X
, 0, 0, 0); }
533 bpf_set_curr_instr
(BPF_ALU | BPF_OR | BPF_K
, 0, 0, $3); }
535 bpf_set_curr_instr
(BPF_ALU | BPF_OR | BPF_X
, 0, 0, 0); }
537 bpf_set_curr_instr
(BPF_ALU | BPF_OR | BPF_X
, 0, 0, 0); }
541 : OP_XOR
'#' number
{
542 bpf_set_curr_instr
(BPF_ALU | BPF_XOR | BPF_K
, 0, 0, $3); }
544 bpf_set_curr_instr
(BPF_ALU | BPF_XOR | BPF_X
, 0, 0, 0); }
546 bpf_set_curr_instr
(BPF_ALU | BPF_XOR | BPF_X
, 0, 0, 0); }
550 : OP_LSH
'#' number
{
551 bpf_set_curr_instr
(BPF_ALU | BPF_LSH | BPF_K
, 0, 0, $3); }
553 bpf_set_curr_instr
(BPF_ALU | BPF_LSH | BPF_X
, 0, 0, 0); }
555 bpf_set_curr_instr
(BPF_ALU | BPF_LSH | BPF_X
, 0, 0, 0); }
559 : OP_RSH
'#' number
{
560 bpf_set_curr_instr
(BPF_ALU | BPF_RSH | BPF_K
, 0, 0, $3); }
562 bpf_set_curr_instr
(BPF_ALU | BPF_RSH | BPF_X
, 0, 0, 0); }
564 bpf_set_curr_instr
(BPF_ALU | BPF_RSH | BPF_X
, 0, 0, 0); }
569 bpf_set_curr_instr
(BPF_RET | BPF_A
, 0, 0, 0); }
571 bpf_set_curr_instr
(BPF_RET | BPF_A
, 0, 0, 0); }
573 bpf_set_curr_instr
(BPF_RET | BPF_X
, 0, 0, 0); }
575 bpf_set_curr_instr
(BPF_RET | BPF_X
, 0, 0, 0); }
576 | OP_RET
'#' number
{
577 bpf_set_curr_instr
(BPF_RET | BPF_K
, 0, 0, $3); }
582 bpf_set_curr_instr
(BPF_MISC | BPF_TAX
, 0, 0, 0); }
587 bpf_set_curr_instr
(BPF_MISC | BPF_TXA
, 0, 0, 0); }
592 static int curr_instr
= 0;
593 static struct sock_filter out
[BPF_MAXINSNS
];
594 static char **labels
, **labels_jt
, **labels_jf
, **labels_k
;
596 static void bpf_assert_max
(void)
598 if
(curr_instr
>= BPF_MAXINSNS
) {
599 fprintf
(stderr
, "only max %u insns allowed!\n", BPF_MAXINSNS
);
604 static void bpf_set_curr_instr
(uint16_t code
, uint8_t jt
, uint8_t jf
,
608 out
[curr_instr
].code
= code
;
609 out
[curr_instr
].jt
= jt
;
610 out
[curr_instr
].jf
= jf
;
611 out
[curr_instr
].k
= k
;
615 static void bpf_set_curr_label
(char *label
)
618 labels
[curr_instr
] = label
;
621 static void bpf_set_jmp_label
(char *label
, enum jmp_type type
)
626 labels_jt
[curr_instr
] = label
;
629 labels_jf
[curr_instr
] = label
;
632 labels_k
[curr_instr
] = label
;
637 static int bpf_find_insns_offset
(const char *label
)
639 int i
, max
= curr_instr
, ret
= -ENOENT
;
641 for
(i
= 0; i
< max
; i
++) {
642 if
(labels
[i
] && !strcmp
(label
, labels
[i
])) {
648 if
(ret
== -ENOENT
) {
649 fprintf
(stderr
, "no such label \'%s\'!\n", label
);
656 static void bpf_stage_1_insert_insns
(void)
661 static void bpf_reduce_k_jumps
(void)
665 for
(i
= 0; i
< curr_instr
; i
++) {
667 int off
= bpf_find_insns_offset
(labels_k
[i
]);
668 out
[i
].k
= (uint32_t) (off
- i
- 1);
673 static void bpf_reduce_jt_jumps
(void)
677 for
(i
= 0; i
< curr_instr
; i
++) {
679 int off
= bpf_find_insns_offset
(labels_jt
[i
]);
680 out
[i
].jt
= (uint8_t) (off
- i
-1);
685 static void bpf_reduce_jf_jumps
(void)
689 for
(i
= 0; i
< curr_instr
; i
++) {
691 int off
= bpf_find_insns_offset
(labels_jf
[i
]);
692 out
[i
].jf
= (uint8_t) (off
- i
- 1);
697 static void bpf_stage_2_reduce_labels
(void)
699 bpf_reduce_k_jumps
();
700 bpf_reduce_jt_jumps
();
701 bpf_reduce_jf_jumps
();
704 static void bpf_pretty_print_c
(void)
708 for
(i
= 0; i
< curr_instr
; i
++)
709 printf
("{ %#04x, %2u, %2u, %#010x },\n", out
[i
].code
,
710 out
[i
].jt
, out
[i
].jf
, out
[i
].k
);
713 static void bpf_pretty_print
(void)
717 printf
("%u,", curr_instr
);
718 for
(i
= 0; i
< curr_instr
; i
++)
719 printf
("%u %u %u %u,", out
[i
].code
,
720 out
[i
].jt
, out
[i
].jf
, out
[i
].k
);
724 static void bpf_init
(void)
726 memset
(out
, 0, sizeof
(out
));
728 labels
= calloc
(BPF_MAXINSNS
, sizeof
(*labels
));
730 labels_jt
= calloc
(BPF_MAXINSNS
, sizeof
(*labels_jt
));
732 labels_jf
= calloc
(BPF_MAXINSNS
, sizeof
(*labels_jf
));
734 labels_k
= calloc
(BPF_MAXINSNS
, sizeof
(*labels_k
));
738 static void bpf_destroy_labels
(void)
742 for
(i
= 0; i
< curr_instr
; i
++) {
750 static void bpf_destroy
(void)
752 bpf_destroy_labels
();
759 void bpf_asm_compile
(FILE *fp
, bool cstyle
)
764 bpf_stage_1_insert_insns
();
765 bpf_stage_2_reduce_labels
();
769 bpf_pretty_print_c
();
777 void yyerror(const char *str
)