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_VLANT K_VLANP 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
); }
159 bpf_set_curr_instr
(BPF_LD | BPF_B | BPF_ABS
, 0, 0,
160 SKF_AD_OFF
+ SKF_AD_VLAN_TAG
); }
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
); }
173 : OP_LDH
'[' 'x' '+' number
']' {
174 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_IND
, 0, 0, $5); }
175 | OP_LDH
'[' '%' 'x' '+' number
']' {
176 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_IND
, 0, 0, $6); }
177 | OP_LDH
'[' number
']' {
178 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0, $3); }
180 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
181 SKF_AD_OFF
+ SKF_AD_PROTOCOL
); }
183 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
184 SKF_AD_OFF
+ SKF_AD_PKTTYPE
); }
186 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
187 SKF_AD_OFF
+ SKF_AD_IFINDEX
); }
189 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
190 SKF_AD_OFF
+ SKF_AD_NLATTR
); }
191 | OP_LDH K_NLATTR_NEST
{
192 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
193 SKF_AD_OFF
+ SKF_AD_NLATTR_NEST
); }
195 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
196 SKF_AD_OFF
+ SKF_AD_MARK
); }
198 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
199 SKF_AD_OFF
+ SKF_AD_QUEUE
); }
201 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
202 SKF_AD_OFF
+ SKF_AD_HATYPE
); }
204 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
205 SKF_AD_OFF
+ SKF_AD_RXHASH
); }
207 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
208 SKF_AD_OFF
+ SKF_AD_CPU
); }
210 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
211 SKF_AD_OFF
+ SKF_AD_VLAN_TAG
); }
213 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
214 SKF_AD_OFF
+ SKF_AD_VLAN_TAG_PRESENT
); }
216 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
217 SKF_AD_OFF
+ SKF_AD_PAY_OFFSET
); }
219 bpf_set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
220 SKF_AD_OFF
+ SKF_AD_RANDOM
); }
224 : OP_LDI
'#' number
{
225 bpf_set_curr_instr
(BPF_LD | BPF_IMM
, 0, 0, $3); }
227 bpf_set_curr_instr
(BPF_LD | BPF_IMM
, 0, 0, $2); }
232 bpf_set_curr_instr
(BPF_LD | BPF_IMM
, 0, 0, $3); }
234 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_LEN
, 0, 0, 0); }
236 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
237 SKF_AD_OFF
+ SKF_AD_PROTOCOL
); }
239 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
240 SKF_AD_OFF
+ SKF_AD_PKTTYPE
); }
242 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
243 SKF_AD_OFF
+ SKF_AD_IFINDEX
); }
245 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
246 SKF_AD_OFF
+ SKF_AD_NLATTR
); }
247 | OP_LD K_NLATTR_NEST
{
248 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
249 SKF_AD_OFF
+ SKF_AD_NLATTR_NEST
); }
251 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
252 SKF_AD_OFF
+ SKF_AD_MARK
); }
254 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
255 SKF_AD_OFF
+ SKF_AD_QUEUE
); }
257 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
258 SKF_AD_OFF
+ SKF_AD_HATYPE
); }
260 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
261 SKF_AD_OFF
+ SKF_AD_RXHASH
); }
263 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
264 SKF_AD_OFF
+ SKF_AD_CPU
); }
266 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
267 SKF_AD_OFF
+ SKF_AD_VLAN_TAG
); }
269 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
270 SKF_AD_OFF
+ SKF_AD_VLAN_TAG_PRESENT
); }
272 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
273 SKF_AD_OFF
+ SKF_AD_PAY_OFFSET
); }
275 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
276 SKF_AD_OFF
+ SKF_AD_RANDOM
); }
277 | OP_LD
'M' '[' number
']' {
278 bpf_set_curr_instr
(BPF_LD | BPF_MEM
, 0, 0, $4); }
279 | OP_LD
'[' 'x' '+' number
']' {
280 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_IND
, 0, 0, $5); }
281 | OP_LD
'[' '%' 'x' '+' number
']' {
282 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_IND
, 0, 0, $6); }
283 | OP_LD
'[' number
']' {
284 bpf_set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0, $3); }
288 : OP_LDXI
'#' number
{
289 bpf_set_curr_instr
(BPF_LDX | BPF_IMM
, 0, 0, $3); }
291 bpf_set_curr_instr
(BPF_LDX | BPF_IMM
, 0, 0, $2); }
295 : OP_LDX
'#' number
{
296 bpf_set_curr_instr
(BPF_LDX | BPF_IMM
, 0, 0, $3); }
298 bpf_set_curr_instr
(BPF_LDX | BPF_W | BPF_LEN
, 0, 0, 0); }
299 | OP_LDX
'M' '[' number
']' {
300 bpf_set_curr_instr
(BPF_LDX | BPF_MEM
, 0, 0, $4); }
301 | OP_LDXB number
'*' '(' '[' number
']' '&' number
')' {
302 if
($2 != 4 ||
$9 != 0xf) {
303 fprintf
(stderr
, "ldxb offset not supported!\n");
306 bpf_set_curr_instr
(BPF_LDX | BPF_MSH | BPF_B
, 0, 0, $6); } }
307 | OP_LDX number
'*' '(' '[' number
']' '&' number
')' {
308 if
($2 != 4 ||
$9 != 0xf) {
309 fprintf
(stderr
, "ldxb offset not supported!\n");
312 bpf_set_curr_instr
(BPF_LDX | BPF_MSH | BPF_B
, 0, 0, $6); } }
316 : OP_ST
'M' '[' number
']' {
317 bpf_set_curr_instr
(BPF_ST
, 0, 0, $4); }
321 : OP_STX
'M' '[' number
']' {
322 bpf_set_curr_instr
(BPF_STX
, 0, 0, $4); }
327 bpf_set_jmp_label
($2, JKL
);
328 bpf_set_curr_instr
(BPF_JMP | BPF_JA
, 0, 0, 0); }
332 : OP_JEQ
'#' number
',' label
',' label
{
333 bpf_set_jmp_label
($5, JTL
);
334 bpf_set_jmp_label
($7, JFL
);
335 bpf_set_curr_instr
(BPF_JMP | BPF_JEQ | BPF_K
, 0, 0, $3); }
336 | OP_JEQ
'x' ',' label
',' label
{
337 bpf_set_jmp_label
($4, JTL
);
338 bpf_set_jmp_label
($6, JFL
);
339 bpf_set_curr_instr
(BPF_JMP | BPF_JEQ | BPF_X
, 0, 0, 0); }
340 | OP_JEQ
'%' 'x' ',' label
',' label
{
341 bpf_set_jmp_label
($5, JTL
);
342 bpf_set_jmp_label
($7, JFL
);
343 bpf_set_curr_instr
(BPF_JMP | BPF_JEQ | BPF_X
, 0, 0, 0); }
344 | OP_JEQ
'#' number
',' label
{
345 bpf_set_jmp_label
($5, JTL
);
346 bpf_set_curr_instr
(BPF_JMP | BPF_JEQ | BPF_K
, 0, 0, $3); }
347 | OP_JEQ
'x' ',' label
{
348 bpf_set_jmp_label
($4, JTL
);
349 bpf_set_curr_instr
(BPF_JMP | BPF_JEQ | BPF_X
, 0, 0, 0); }
350 | OP_JEQ
'%' 'x' ',' label
{
351 bpf_set_jmp_label
($5, JTL
);
352 bpf_set_curr_instr
(BPF_JMP | BPF_JEQ | BPF_X
, 0, 0, 0); }
356 : OP_JNEQ
'#' number
',' label
{
357 bpf_set_jmp_label
($5, JFL
);
358 bpf_set_curr_instr
(BPF_JMP | BPF_JEQ | BPF_K
, 0, 0, $3); }
359 | OP_JNEQ
'x' ',' label
{
360 bpf_set_jmp_label
($4, JFL
);
361 bpf_set_curr_instr
(BPF_JMP | BPF_JEQ | BPF_X
, 0, 0, 0); }
362 | OP_JNEQ
'%' 'x' ',' label
{
363 bpf_set_jmp_label
($5, JFL
);
364 bpf_set_curr_instr
(BPF_JMP | BPF_JEQ | BPF_X
, 0, 0, 0); }
368 : OP_JLT
'#' number
',' label
{
369 bpf_set_jmp_label
($5, JFL
);
370 bpf_set_curr_instr
(BPF_JMP | BPF_JGE | BPF_K
, 0, 0, $3); }
371 | OP_JLT
'x' ',' label
{
372 bpf_set_jmp_label
($4, JFL
);
373 bpf_set_curr_instr
(BPF_JMP | BPF_JGE | BPF_X
, 0, 0, 0); }
374 | OP_JLT
'%' 'x' ',' label
{
375 bpf_set_jmp_label
($5, JFL
);
376 bpf_set_curr_instr
(BPF_JMP | BPF_JGE | BPF_X
, 0, 0, 0); }
380 : OP_JLE
'#' number
',' label
{
381 bpf_set_jmp_label
($5, JFL
);
382 bpf_set_curr_instr
(BPF_JMP | BPF_JGT | BPF_K
, 0, 0, $3); }
383 | OP_JLE
'x' ',' label
{
384 bpf_set_jmp_label
($4, JFL
);
385 bpf_set_curr_instr
(BPF_JMP | BPF_JGT | BPF_X
, 0, 0, 0); }
386 | OP_JLE
'%' 'x' ',' label
{
387 bpf_set_jmp_label
($5, JFL
);
388 bpf_set_curr_instr
(BPF_JMP | BPF_JGT | BPF_X
, 0, 0, 0); }
392 : OP_JGT
'#' number
',' label
',' label
{
393 bpf_set_jmp_label
($5, JTL
);
394 bpf_set_jmp_label
($7, JFL
);
395 bpf_set_curr_instr
(BPF_JMP | BPF_JGT | BPF_K
, 0, 0, $3); }
396 | OP_JGT
'x' ',' label
',' label
{
397 bpf_set_jmp_label
($4, JTL
);
398 bpf_set_jmp_label
($6, JFL
);
399 bpf_set_curr_instr
(BPF_JMP | BPF_JGT | BPF_X
, 0, 0, 0); }
400 | OP_JGT
'%' 'x' ',' label
',' label
{
401 bpf_set_jmp_label
($5, JTL
);
402 bpf_set_jmp_label
($7, JFL
);
403 bpf_set_curr_instr
(BPF_JMP | BPF_JGT | BPF_X
, 0, 0, 0); }
404 | OP_JGT
'#' number
',' label
{
405 bpf_set_jmp_label
($5, JTL
);
406 bpf_set_curr_instr
(BPF_JMP | BPF_JGT | BPF_K
, 0, 0, $3); }
407 | OP_JGT
'x' ',' label
{
408 bpf_set_jmp_label
($4, JTL
);
409 bpf_set_curr_instr
(BPF_JMP | BPF_JGT | BPF_X
, 0, 0, 0); }
410 | OP_JGT
'%' 'x' ',' label
{
411 bpf_set_jmp_label
($5, JTL
);
412 bpf_set_curr_instr
(BPF_JMP | BPF_JGT | BPF_X
, 0, 0, 0); }
416 : OP_JGE
'#' number
',' label
',' label
{
417 bpf_set_jmp_label
($5, JTL
);
418 bpf_set_jmp_label
($7, JFL
);
419 bpf_set_curr_instr
(BPF_JMP | BPF_JGE | BPF_K
, 0, 0, $3); }
420 | OP_JGE
'x' ',' label
',' label
{
421 bpf_set_jmp_label
($4, JTL
);
422 bpf_set_jmp_label
($6, JFL
);
423 bpf_set_curr_instr
(BPF_JMP | BPF_JGE | BPF_X
, 0, 0, 0); }
424 | OP_JGE
'%' 'x' ',' label
',' label
{
425 bpf_set_jmp_label
($5, JTL
);
426 bpf_set_jmp_label
($7, JFL
);
427 bpf_set_curr_instr
(BPF_JMP | BPF_JGE | BPF_X
, 0, 0, 0); }
428 | OP_JGE
'#' number
',' label
{
429 bpf_set_jmp_label
($5, JTL
);
430 bpf_set_curr_instr
(BPF_JMP | BPF_JGE | BPF_K
, 0, 0, $3); }
431 | OP_JGE
'x' ',' label
{
432 bpf_set_jmp_label
($4, JTL
);
433 bpf_set_curr_instr
(BPF_JMP | BPF_JGE | BPF_X
, 0, 0, 0); }
434 | OP_JGE
'%' 'x' ',' label
{
435 bpf_set_jmp_label
($5, JTL
);
436 bpf_set_curr_instr
(BPF_JMP | BPF_JGE | BPF_X
, 0, 0, 0); }
440 : OP_JSET
'#' number
',' label
',' label
{
441 bpf_set_jmp_label
($5, JTL
);
442 bpf_set_jmp_label
($7, JFL
);
443 bpf_set_curr_instr
(BPF_JMP | BPF_JSET | BPF_K
, 0, 0, $3); }
444 | OP_JSET
'x' ',' label
',' label
{
445 bpf_set_jmp_label
($4, JTL
);
446 bpf_set_jmp_label
($6, JFL
);
447 bpf_set_curr_instr
(BPF_JMP | BPF_JSET | BPF_X
, 0, 0, 0); }
448 | OP_JSET
'%' 'x' ',' label
',' label
{
449 bpf_set_jmp_label
($5, JTL
);
450 bpf_set_jmp_label
($7, JFL
);
451 bpf_set_curr_instr
(BPF_JMP | BPF_JSET | BPF_X
, 0, 0, 0); }
452 | OP_JSET
'#' number
',' label
{
453 bpf_set_jmp_label
($5, JTL
);
454 bpf_set_curr_instr
(BPF_JMP | BPF_JSET | BPF_K
, 0, 0, $3); }
455 | OP_JSET
'x' ',' label
{
456 bpf_set_jmp_label
($4, JTL
);
457 bpf_set_curr_instr
(BPF_JMP | BPF_JSET | BPF_X
, 0, 0, 0); }
458 | OP_JSET
'%' 'x' ',' label
{
459 bpf_set_jmp_label
($5, JTL
);
460 bpf_set_curr_instr
(BPF_JMP | BPF_JSET | BPF_X
, 0, 0, 0); }
464 : OP_ADD
'#' number
{
465 bpf_set_curr_instr
(BPF_ALU | BPF_ADD | BPF_K
, 0, 0, $3); }
467 bpf_set_curr_instr
(BPF_ALU | BPF_ADD | BPF_X
, 0, 0, 0); }
469 bpf_set_curr_instr
(BPF_ALU | BPF_ADD | BPF_X
, 0, 0, 0); }
473 : OP_SUB
'#' number
{
474 bpf_set_curr_instr
(BPF_ALU | BPF_SUB | BPF_K
, 0, 0, $3); }
476 bpf_set_curr_instr
(BPF_ALU | BPF_SUB | BPF_X
, 0, 0, 0); }
478 bpf_set_curr_instr
(BPF_ALU | BPF_SUB | BPF_X
, 0, 0, 0); }
482 : OP_MUL
'#' number
{
483 bpf_set_curr_instr
(BPF_ALU | BPF_MUL | BPF_K
, 0, 0, $3); }
485 bpf_set_curr_instr
(BPF_ALU | BPF_MUL | BPF_X
, 0, 0, 0); }
487 bpf_set_curr_instr
(BPF_ALU | BPF_MUL | BPF_X
, 0, 0, 0); }
491 : OP_DIV
'#' number
{
492 bpf_set_curr_instr
(BPF_ALU | BPF_DIV | BPF_K
, 0, 0, $3); }
494 bpf_set_curr_instr
(BPF_ALU | BPF_DIV | BPF_X
, 0, 0, 0); }
496 bpf_set_curr_instr
(BPF_ALU | BPF_DIV | BPF_X
, 0, 0, 0); }
500 : OP_MOD
'#' number
{
501 bpf_set_curr_instr
(BPF_ALU | BPF_MOD | BPF_K
, 0, 0, $3); }
503 bpf_set_curr_instr
(BPF_ALU | BPF_MOD | BPF_X
, 0, 0, 0); }
505 bpf_set_curr_instr
(BPF_ALU | BPF_MOD | BPF_X
, 0, 0, 0); }
510 bpf_set_curr_instr
(BPF_ALU | BPF_NEG
, 0, 0, 0); }
514 : OP_AND
'#' number
{
515 bpf_set_curr_instr
(BPF_ALU | BPF_AND | BPF_K
, 0, 0, $3); }
517 bpf_set_curr_instr
(BPF_ALU | BPF_AND | BPF_X
, 0, 0, 0); }
519 bpf_set_curr_instr
(BPF_ALU | BPF_AND | BPF_X
, 0, 0, 0); }
524 bpf_set_curr_instr
(BPF_ALU | BPF_OR | BPF_K
, 0, 0, $3); }
526 bpf_set_curr_instr
(BPF_ALU | BPF_OR | BPF_X
, 0, 0, 0); }
528 bpf_set_curr_instr
(BPF_ALU | BPF_OR | BPF_X
, 0, 0, 0); }
532 : OP_XOR
'#' number
{
533 bpf_set_curr_instr
(BPF_ALU | BPF_XOR | BPF_K
, 0, 0, $3); }
535 bpf_set_curr_instr
(BPF_ALU | BPF_XOR | BPF_X
, 0, 0, 0); }
537 bpf_set_curr_instr
(BPF_ALU | BPF_XOR | BPF_X
, 0, 0, 0); }
541 : OP_LSH
'#' number
{
542 bpf_set_curr_instr
(BPF_ALU | BPF_LSH | BPF_K
, 0, 0, $3); }
544 bpf_set_curr_instr
(BPF_ALU | BPF_LSH | BPF_X
, 0, 0, 0); }
546 bpf_set_curr_instr
(BPF_ALU | BPF_LSH | BPF_X
, 0, 0, 0); }
550 : OP_RSH
'#' number
{
551 bpf_set_curr_instr
(BPF_ALU | BPF_RSH | BPF_K
, 0, 0, $3); }
553 bpf_set_curr_instr
(BPF_ALU | BPF_RSH | BPF_X
, 0, 0, 0); }
555 bpf_set_curr_instr
(BPF_ALU | BPF_RSH | BPF_X
, 0, 0, 0); }
560 bpf_set_curr_instr
(BPF_RET | BPF_A
, 0, 0, 0); }
562 bpf_set_curr_instr
(BPF_RET | BPF_A
, 0, 0, 0); }
564 bpf_set_curr_instr
(BPF_RET | BPF_X
, 0, 0, 0); }
566 bpf_set_curr_instr
(BPF_RET | BPF_X
, 0, 0, 0); }
567 | OP_RET
'#' number
{
568 bpf_set_curr_instr
(BPF_RET | BPF_K
, 0, 0, $3); }
573 bpf_set_curr_instr
(BPF_MISC | BPF_TAX
, 0, 0, 0); }
578 bpf_set_curr_instr
(BPF_MISC | BPF_TXA
, 0, 0, 0); }
583 static int curr_instr
= 0;
584 static struct sock_filter out
[BPF_MAXINSNS
];
585 static char **labels
, **labels_jt
, **labels_jf
, **labels_k
;
587 static void bpf_assert_max
(void)
589 if
(curr_instr
>= BPF_MAXINSNS
) {
590 fprintf
(stderr
, "only max %u insns allowed!\n", BPF_MAXINSNS
);
595 static void bpf_set_curr_instr
(uint16_t code
, uint8_t jt
, uint8_t jf
,
599 out
[curr_instr
].code
= code
;
600 out
[curr_instr
].jt
= jt
;
601 out
[curr_instr
].jf
= jf
;
602 out
[curr_instr
].k
= k
;
606 static void bpf_set_curr_label
(char *label
)
609 labels
[curr_instr
] = label
;
612 static void bpf_set_jmp_label
(char *label
, enum jmp_type type
)
617 labels_jt
[curr_instr
] = label
;
620 labels_jf
[curr_instr
] = label
;
623 labels_k
[curr_instr
] = label
;
628 static int bpf_find_insns_offset
(const char *label
)
630 int i
, max
= curr_instr
, ret
= -ENOENT
;
632 for
(i
= 0; i
< max
; i
++) {
633 if
(labels
[i
] && !strcmp
(label
, labels
[i
])) {
639 if
(ret
== -ENOENT
) {
640 fprintf
(stderr
, "no such label \'%s\'!\n", label
);
647 static void bpf_stage_1_insert_insns
(void)
652 static void bpf_reduce_k_jumps
(void)
656 for
(i
= 0; i
< curr_instr
; i
++) {
658 int off
= bpf_find_insns_offset
(labels_k
[i
]);
659 out
[i
].k
= (uint32_t) (off
- i
- 1);
664 static void bpf_reduce_jt_jumps
(void)
668 for
(i
= 0; i
< curr_instr
; i
++) {
670 int off
= bpf_find_insns_offset
(labels_jt
[i
]);
671 out
[i
].jt
= (uint8_t) (off
- i
-1);
676 static void bpf_reduce_jf_jumps
(void)
680 for
(i
= 0; i
< curr_instr
; i
++) {
682 int off
= bpf_find_insns_offset
(labels_jf
[i
]);
683 out
[i
].jf
= (uint8_t) (off
- i
- 1);
688 static void bpf_stage_2_reduce_labels
(void)
690 bpf_reduce_k_jumps
();
691 bpf_reduce_jt_jumps
();
692 bpf_reduce_jf_jumps
();
695 static void bpf_pretty_print_c
(void)
699 for
(i
= 0; i
< curr_instr
; i
++)
700 printf
("{ %#04x, %2u, %2u, %#010x },\n", out
[i
].code
,
701 out
[i
].jt
, out
[i
].jf
, out
[i
].k
);
704 static void bpf_pretty_print
(void)
708 printf
("%u,", curr_instr
);
709 for
(i
= 0; i
< curr_instr
; i
++)
710 printf
("%u %u %u %u,", out
[i
].code
,
711 out
[i
].jt
, out
[i
].jf
, out
[i
].k
);
715 static void bpf_init
(void)
717 memset
(out
, 0, sizeof
(out
));
719 labels
= calloc
(BPF_MAXINSNS
, sizeof
(*labels
));
721 labels_jt
= calloc
(BPF_MAXINSNS
, sizeof
(*labels_jt
));
723 labels_jf
= calloc
(BPF_MAXINSNS
, sizeof
(*labels_jf
));
725 labels_k
= calloc
(BPF_MAXINSNS
, sizeof
(*labels_k
));
729 static void bpf_destroy_labels
(void)
733 for
(i
= 0; i
< curr_instr
; i
++) {
741 static void bpf_destroy
(void)
743 bpf_destroy_labels
();
750 void bpf_asm_compile
(FILE *fp
, bool cstyle
)
755 bpf_stage_1_insert_insns
();
756 bpf_stage_2_reduce_labels
();
760 bpf_pretty_print_c
();
768 void yyerror(const char *str
)