2 * netsniff-ng - the packet sniffing beast
3 * By Daniel Borkmann <daniel@netsniff-ng.org>
4 * Copyright 2011 Daniel Borkmann <dborkma@tik.ee.ethz.ch>,
5 * Swiss federal institute of technology (ETH Zurich)
6 * Subject to the GPL, version 2.
9 /* yacc-func-prefix: yy */
20 #include <linux/filter.h>
25 #include "bpf_parser.tab.h"
30 static int curr_instr
= 0;
32 static struct sock_filter out
[BPF_MAXINSNS
];
34 static char *labels
[BPF_MAXINSNS
];
35 static char *labels_jt
[BPF_MAXINSNS
];
36 static char *labels_jf
[BPF_MAXINSNS
];
37 static char *labels_k
[BPF_MAXINSNS
];
39 #define YYERROR_VERBOSE 0
41 #define YYENABLE_NLS 1
42 #define YYLTYPE_IS_TRIVIAL 1
46 extern
int yylex(void);
47 extern
void yyerror(const char *);
51 static inline
void check_max_instr
(void)
53 if
(curr_instr
>= BPF_MAXINSNS
)
54 panic
("Exceeded maximal number of instructions!\n");
57 static inline
void set_curr_instr
(uint16_t code
, uint8_t jt
, uint8_t jf
, uint32_t k
)
61 out
[curr_instr
].code
= code
;
62 out
[curr_instr
].jt
= jt
;
63 out
[curr_instr
].jf
= jf
;
64 out
[curr_instr
].k
= k
;
69 static inline
void set_curr_label
(char *label
)
73 labels
[curr_instr
] = label
;
80 static inline
void set_jmp_label
(char *label
, int which
)
86 labels_jt
[curr_instr
] = label
;
89 labels_jf
[curr_instr
] = label
;
92 labels_k
[curr_instr
] = label
;
99 static int find_intr_offset_or_panic
(char *label_to_search
)
101 int i
, max
= curr_instr
, ret
= -ENOENT
;
103 bug_on
(!label_to_search
);
105 for
(i
= 0; i
< max
; ++i
) {
106 if
(labels
[i
] != NULL
) {
107 /* Both are \0-terminated! */
108 if
(!strcmp
(label_to_search
, labels
[i
])) {
116 panic
("No such label!\n");
128 %token OP_LDB OP_LDH OP_LD OP_LDX OP_ST OP_STX OP_JMP OP_JEQ OP_JGT OP_JGE
129 %token OP_JSET OP_ADD OP_SUB OP_MUL OP_DIV OP_AND OP_OR OP_XOR OP_LSH OP_RSH
130 %token OP_RET OP_TAX OP_TXA OP_LDXB OP_MOD OP_NEG OP_JNEQ OP_JLT OP_JLE OP_LDI
133 %token K_PKT_LEN K_PROTO K_TYPE K_NLATTR K_NLATTR_NEST K_MARK K_QUEUE K_HATYPE
134 %token K_RXHASH K_CPU K_IFIDX K_VLANT K_VLANP K_POFF
136 %token
':' ',' '[' ']' '(' ')' 'x' 'a' '+' 'M' '*' '&' '#' '%'
140 %type
<number
> number
193 : label
':' { set_curr_label
($1); }
197 : OP_LDB
'[' 'x' '+' number
']' {
198 set_curr_instr
(BPF_LD | BPF_B | BPF_IND
, 0, 0, $5); }
199 | OP_LDB
'[' '%' 'x' '+' number
']' {
200 set_curr_instr
(BPF_LD | BPF_B | BPF_IND
, 0, 0, $6); }
201 | OP_LDB
'[' number
']' {
202 set_curr_instr
(BPF_LD | BPF_B | BPF_ABS
, 0, 0, $3); }
204 set_curr_instr
(BPF_LD | BPF_B | BPF_ABS
, 0, 0,
205 SKF_AD_OFF
+ SKF_AD_PROTOCOL
); }
207 set_curr_instr
(BPF_LD | BPF_B | BPF_ABS
, 0, 0,
208 SKF_AD_OFF
+ SKF_AD_PKTTYPE
); }
210 set_curr_instr
(BPF_LD | BPF_B | BPF_ABS
, 0, 0,
211 SKF_AD_OFF
+ SKF_AD_IFINDEX
); }
213 set_curr_instr
(BPF_LD | BPF_B | BPF_ABS
, 0, 0,
214 SKF_AD_OFF
+ SKF_AD_NLATTR
); }
215 | OP_LDB K_NLATTR_NEST
{
216 set_curr_instr
(BPF_LD | BPF_B | BPF_ABS
, 0, 0,
217 SKF_AD_OFF
+ SKF_AD_NLATTR_NEST
); }
219 set_curr_instr
(BPF_LD | BPF_B | BPF_ABS
, 0, 0,
220 SKF_AD_OFF
+ SKF_AD_MARK
); }
222 set_curr_instr
(BPF_LD | BPF_B | BPF_ABS
, 0, 0,
223 SKF_AD_OFF
+ SKF_AD_QUEUE
); }
225 set_curr_instr
(BPF_LD | BPF_B | BPF_ABS
, 0, 0,
226 SKF_AD_OFF
+ SKF_AD_HATYPE
); }
228 set_curr_instr
(BPF_LD | BPF_B | BPF_ABS
, 0, 0,
229 SKF_AD_OFF
+ SKF_AD_RXHASH
); }
231 set_curr_instr
(BPF_LD | BPF_B | BPF_ABS
, 0, 0,
232 SKF_AD_OFF
+ SKF_AD_CPU
); }
234 set_curr_instr
(BPF_LD | BPF_B | BPF_ABS
, 0, 0,
235 SKF_AD_OFF
+ SKF_AD_VLAN_TAG
); }
237 set_curr_instr
(BPF_LD | BPF_B | BPF_ABS
, 0, 0,
238 SKF_AD_OFF
+ SKF_AD_VLAN_TAG_PRESENT
); }
240 set_curr_instr
(BPF_LD | BPF_B | BPF_ABS
, 0, 0,
241 SKF_AD_OFF
+ SKF_AD_PAY_OFFSET
); }
245 : OP_LDH
'[' 'x' '+' number
']' {
246 set_curr_instr
(BPF_LD | BPF_H | BPF_IND
, 0, 0, $5); }
247 | OP_LDH
'[' '%' 'x' '+' number
']' {
248 set_curr_instr
(BPF_LD | BPF_H | BPF_IND
, 0, 0, $6); }
249 | OP_LDH
'[' number
']' {
250 set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0, $3); }
252 set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
253 SKF_AD_OFF
+ SKF_AD_PROTOCOL
); }
255 set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
256 SKF_AD_OFF
+ SKF_AD_PKTTYPE
); }
258 set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
259 SKF_AD_OFF
+ SKF_AD_IFINDEX
); }
261 set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
262 SKF_AD_OFF
+ SKF_AD_NLATTR
); }
263 | OP_LDH K_NLATTR_NEST
{
264 set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
265 SKF_AD_OFF
+ SKF_AD_NLATTR_NEST
); }
267 set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
268 SKF_AD_OFF
+ SKF_AD_MARK
); }
270 set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
271 SKF_AD_OFF
+ SKF_AD_QUEUE
); }
273 set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
274 SKF_AD_OFF
+ SKF_AD_HATYPE
); }
276 set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
277 SKF_AD_OFF
+ SKF_AD_RXHASH
); }
279 set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
280 SKF_AD_OFF
+ SKF_AD_CPU
); }
282 set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
283 SKF_AD_OFF
+ SKF_AD_VLAN_TAG
); }
285 set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
286 SKF_AD_OFF
+ SKF_AD_VLAN_TAG_PRESENT
); }
288 set_curr_instr
(BPF_LD | BPF_H | BPF_ABS
, 0, 0,
289 SKF_AD_OFF
+ SKF_AD_PAY_OFFSET
); }
293 : OP_LDI
'#' number
{
294 set_curr_instr
(BPF_LD | BPF_IMM
, 0, 0, $3); }
296 set_curr_instr
(BPF_LD | BPF_IMM
, 0, 0, $2); }
301 set_curr_instr
(BPF_LD | BPF_IMM
, 0, 0, $3); }
303 set_curr_instr
(BPF_LD | BPF_W | BPF_LEN
, 0, 0, 0); }
305 set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
306 SKF_AD_OFF
+ SKF_AD_PROTOCOL
); }
308 set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
309 SKF_AD_OFF
+ SKF_AD_PKTTYPE
); }
311 set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
312 SKF_AD_OFF
+ SKF_AD_IFINDEX
); }
314 set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
315 SKF_AD_OFF
+ SKF_AD_NLATTR
); }
316 | OP_LD K_NLATTR_NEST
{
317 set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
318 SKF_AD_OFF
+ SKF_AD_NLATTR_NEST
); }
320 set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
321 SKF_AD_OFF
+ SKF_AD_MARK
); }
323 set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
324 SKF_AD_OFF
+ SKF_AD_QUEUE
); }
326 set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
327 SKF_AD_OFF
+ SKF_AD_HATYPE
); }
329 set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
330 SKF_AD_OFF
+ SKF_AD_RXHASH
); }
332 set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
333 SKF_AD_OFF
+ SKF_AD_CPU
); }
335 set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
336 SKF_AD_OFF
+ SKF_AD_VLAN_TAG
); }
338 set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
339 SKF_AD_OFF
+ SKF_AD_VLAN_TAG_PRESENT
); }
341 set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0,
342 SKF_AD_OFF
+ SKF_AD_PAY_OFFSET
); }
343 | OP_LD
'M' '[' number
']' {
344 set_curr_instr
(BPF_LD | BPF_MEM
, 0, 0, $4); }
345 | OP_LD
'[' 'x' '+' number
']' {
346 set_curr_instr
(BPF_LD | BPF_W | BPF_IND
, 0, 0, $5); }
347 | OP_LD
'[' '%' 'x' '+' number
']' {
348 set_curr_instr
(BPF_LD | BPF_W | BPF_IND
, 0, 0, $6); }
349 | OP_LD
'[' number
']' {
350 set_curr_instr
(BPF_LD | BPF_W | BPF_ABS
, 0, 0, $3); }
354 : OP_LDXI
'#' number
{
355 set_curr_instr
(BPF_LDX | BPF_IMM
, 0, 0, $3); }
357 set_curr_instr
(BPF_LDX | BPF_IMM
, 0, 0, $2); }
361 : OP_LDX
'#' number
{
362 set_curr_instr
(BPF_LDX | BPF_IMM
, 0, 0, $3); }
364 set_curr_instr
(BPF_LDX | BPF_W | BPF_LEN
, 0, 0, 0); }
365 | OP_LDX
'M' '[' number
']' {
366 set_curr_instr
(BPF_LDX | BPF_MEM
, 0, 0, $4); }
367 | OP_LDXB number
'*' '(' '[' number
']' '&' number
')' {
368 if
($2 != 4 ||
$9 != 0xf) {
369 panic
("ldxb offset not supported!\n");
371 set_curr_instr
(BPF_LDX | BPF_MSH | BPF_B
, 0, 0, $6); } }
372 | OP_LDX number
'*' '(' '[' number
']' '&' number
')' {
373 if
($2 != 4 ||
$9 != 0xf) {
374 panic
("ldxb offset not supported!\n");
376 set_curr_instr
(BPF_LDX | BPF_MSH | BPF_B
, 0, 0, $6); } }
380 : OP_ST
'M' '[' number
']' {
381 set_curr_instr
(BPF_ST
, 0, 0, $4); }
385 : OP_STX
'M' '[' number
']' {
386 set_curr_instr
(BPF_STX
, 0, 0, $4); }
391 set_jmp_label
($2, JKL
);
392 set_curr_instr
(BPF_JMP | BPF_JA
, 0, 0, 0); }
396 : OP_JEQ
'#' number
',' label
',' label
{
397 set_jmp_label
($5, JTL
);
398 set_jmp_label
($7, JFL
);
399 set_curr_instr
(BPF_JMP | BPF_JEQ | BPF_K
, 0, 0, $3); }
400 | OP_JEQ
'x' ',' label
',' label
{
401 set_jmp_label
($4, JTL
);
402 set_jmp_label
($6, JFL
);
403 set_curr_instr
(BPF_JMP | BPF_JEQ | BPF_X
, 0, 0, 0); }
404 | OP_JEQ
'%' 'x' ',' label
',' label
{
405 set_jmp_label
($5, JTL
);
406 set_jmp_label
($7, JFL
);
407 set_curr_instr
(BPF_JMP | BPF_JEQ | BPF_X
, 0, 0, 0); }
408 | OP_JEQ
'#' number
',' label
{
409 set_jmp_label
($5, JTL
);
410 set_curr_instr
(BPF_JMP | BPF_JEQ | BPF_K
, 0, 0, $3); }
411 | OP_JEQ
'x' ',' label
{
412 set_jmp_label
($4, JTL
);
413 set_curr_instr
(BPF_JMP | BPF_JEQ | BPF_X
, 0, 0, 0); }
414 | OP_JEQ
'%' 'x' ',' label
{
415 set_jmp_label
($5, JTL
);
416 set_curr_instr
(BPF_JMP | BPF_JEQ | BPF_X
, 0, 0, 0); }
420 : OP_JNEQ
'#' number
',' label
{
421 set_jmp_label
($5, JFL
);
422 set_curr_instr
(BPF_JMP | BPF_JEQ | BPF_K
, 0, 0, $3); }
423 | OP_JNEQ
'x' ',' label
{
424 set_jmp_label
($4, JFL
);
425 set_curr_instr
(BPF_JMP | BPF_JEQ | BPF_X
, 0, 0, 0); }
426 | OP_JNEQ
'%' 'x' ',' label
{
427 set_jmp_label
($5, JFL
);
428 set_curr_instr
(BPF_JMP | BPF_JEQ | BPF_X
, 0, 0, 0); }
432 : OP_JLT
'#' number
',' label
{
433 set_jmp_label
($5, JFL
);
434 set_curr_instr
(BPF_JMP | BPF_JGE | BPF_K
, 0, 0, $3); }
435 | OP_JLT
'x' ',' label
{
436 set_jmp_label
($4, JFL
);
437 set_curr_instr
(BPF_JMP | BPF_JGE | BPF_X
, 0, 0, 0); }
438 | OP_JLT
'%' 'x' ',' label
{
439 set_jmp_label
($5, JFL
);
440 set_curr_instr
(BPF_JMP | BPF_JGE | BPF_X
, 0, 0, 0); }
444 : OP_JLE
'#' number
',' label
{
445 set_jmp_label
($5, JFL
);
446 set_curr_instr
(BPF_JMP | BPF_JGT | BPF_K
, 0, 0, $3); }
447 | OP_JLE
'x' ',' label
{
448 set_jmp_label
($4, JFL
);
449 set_curr_instr
(BPF_JMP | BPF_JGT | BPF_X
, 0, 0, 0); }
450 | OP_JLE
'%' 'x' ',' label
{
451 set_jmp_label
($5, JFL
);
452 set_curr_instr
(BPF_JMP | BPF_JGT | BPF_X
, 0, 0, 0); }
456 : OP_JGT
'#' number
',' label
',' label
{
457 set_jmp_label
($5, JTL
);
458 set_jmp_label
($7, JFL
);
459 set_curr_instr
(BPF_JMP | BPF_JGT | BPF_K
, 0, 0, $3); }
460 | OP_JGT
'x' ',' label
',' label
{
461 set_jmp_label
($4, JTL
);
462 set_jmp_label
($6, JFL
);
463 set_curr_instr
(BPF_JMP | BPF_JGT | BPF_X
, 0, 0, 0); }
464 | OP_JGT
'%' 'x' ',' label
',' label
{
465 set_jmp_label
($5, JTL
);
466 set_jmp_label
($7, JFL
);
467 set_curr_instr
(BPF_JMP | BPF_JGT | BPF_X
, 0, 0, 0); }
468 | OP_JGT
'#' number
',' label
{
469 set_jmp_label
($5, JTL
);
470 set_curr_instr
(BPF_JMP | BPF_JGT | BPF_K
, 0, 0, $3); }
471 | OP_JGT
'x' ',' label
{
472 set_jmp_label
($4, JTL
);
473 set_curr_instr
(BPF_JMP | BPF_JGT | BPF_X
, 0, 0, 0); }
474 | OP_JGT
'%' 'x' ',' label
{
475 set_jmp_label
($5, JTL
);
476 set_curr_instr
(BPF_JMP | BPF_JGT | BPF_X
, 0, 0, 0); }
480 : OP_JGE
'#' number
',' label
',' label
{
481 set_jmp_label
($5, JTL
);
482 set_jmp_label
($7, JFL
);
483 set_curr_instr
(BPF_JMP | BPF_JGE | BPF_K
, 0, 0, $3); }
484 | OP_JGE
'x' ',' label
',' label
{
485 set_jmp_label
($4, JTL
);
486 set_jmp_label
($6, JFL
);
487 set_curr_instr
(BPF_JMP | BPF_JGE | BPF_X
, 0, 0, 0); }
488 | OP_JGE
'%' 'x' ',' label
',' label
{
489 set_jmp_label
($5, JTL
);
490 set_jmp_label
($7, JFL
);
491 set_curr_instr
(BPF_JMP | BPF_JGE | BPF_X
, 0, 0, 0); }
492 | OP_JGE
'#' number
',' label
{
493 set_jmp_label
($5, JTL
);
494 set_curr_instr
(BPF_JMP | BPF_JGE | BPF_K
, 0, 0, $3); }
495 | OP_JGE
'x' ',' label
{
496 set_jmp_label
($4, JTL
);
497 set_curr_instr
(BPF_JMP | BPF_JGE | BPF_X
, 0, 0, 0); }
498 | OP_JGE
'%' 'x' ',' label
{
499 set_jmp_label
($5, JTL
);
500 set_curr_instr
(BPF_JMP | BPF_JGE | BPF_X
, 0, 0, 0); }
504 : OP_JSET
'#' number
',' label
',' label
{
505 set_jmp_label
($5, JTL
);
506 set_jmp_label
($7, JFL
);
507 set_curr_instr
(BPF_JMP | BPF_JSET | BPF_K
, 0, 0, $3); }
508 | OP_JSET
'x' ',' label
',' label
{
509 set_jmp_label
($4, JTL
);
510 set_jmp_label
($6, JFL
);
511 set_curr_instr
(BPF_JMP | BPF_JSET | BPF_X
, 0, 0, 0); }
512 | OP_JSET
'%' 'x' ',' label
',' label
{
513 set_jmp_label
($5, JTL
);
514 set_jmp_label
($7, JFL
);
515 set_curr_instr
(BPF_JMP | BPF_JSET | BPF_X
, 0, 0, 0); }
516 | OP_JSET
'#' number
',' label
{
517 set_jmp_label
($5, JTL
);
518 set_curr_instr
(BPF_JMP | BPF_JSET | BPF_K
, 0, 0, $3); }
519 | OP_JSET
'x' ',' label
{
520 set_jmp_label
($4, JTL
);
521 set_curr_instr
(BPF_JMP | BPF_JSET | BPF_X
, 0, 0, 0); }
522 | OP_JSET
'%' 'x' ',' label
{
523 set_jmp_label
($5, JTL
);
524 set_curr_instr
(BPF_JMP | BPF_JSET | BPF_X
, 0, 0, 0); }
528 : OP_ADD
'#' number
{
529 set_curr_instr
(BPF_ALU | BPF_ADD | BPF_K
, 0, 0, $3); }
531 set_curr_instr
(BPF_ALU | BPF_ADD | BPF_X
, 0, 0, 0); }
533 set_curr_instr
(BPF_ALU | BPF_ADD | BPF_X
, 0, 0, 0); }
537 : OP_SUB
'#' number
{
538 set_curr_instr
(BPF_ALU | BPF_SUB | BPF_K
, 0, 0, $3); }
540 set_curr_instr
(BPF_ALU | BPF_SUB | BPF_X
, 0, 0, 0); }
542 set_curr_instr
(BPF_ALU | BPF_SUB | BPF_X
, 0, 0, 0); }
546 : OP_MUL
'#' number
{
547 set_curr_instr
(BPF_ALU | BPF_MUL | BPF_K
, 0, 0, $3); }
549 set_curr_instr
(BPF_ALU | BPF_MUL | BPF_X
, 0, 0, 0); }
551 set_curr_instr
(BPF_ALU | BPF_MUL | BPF_X
, 0, 0, 0); }
555 : OP_DIV
'#' number
{
556 set_curr_instr
(BPF_ALU | BPF_DIV | BPF_K
, 0, 0, $3); }
558 set_curr_instr
(BPF_ALU | BPF_DIV | BPF_X
, 0, 0, 0); }
560 set_curr_instr
(BPF_ALU | BPF_DIV | BPF_X
, 0, 0, 0); }
564 : OP_MOD
'#' number
{
565 set_curr_instr
(BPF_ALU | BPF_MOD | BPF_K
, 0, 0, $3); }
567 set_curr_instr
(BPF_ALU | BPF_MOD | BPF_X
, 0, 0, 0); }
569 set_curr_instr
(BPF_ALU | BPF_MOD | BPF_X
, 0, 0, 0); }
574 set_curr_instr
(BPF_ALU | BPF_NEG
, 0, 0, 0); }
578 : OP_AND
'#' number
{
579 set_curr_instr
(BPF_ALU | BPF_AND | BPF_K
, 0, 0, $3); }
581 set_curr_instr
(BPF_ALU | BPF_AND | BPF_X
, 0, 0, 0); }
583 set_curr_instr
(BPF_ALU | BPF_AND | BPF_X
, 0, 0, 0); }
588 set_curr_instr
(BPF_ALU | BPF_OR | BPF_K
, 0, 0, $3); }
590 set_curr_instr
(BPF_ALU | BPF_OR | BPF_X
, 0, 0, 0); }
592 set_curr_instr
(BPF_ALU | BPF_OR | BPF_X
, 0, 0, 0); }
596 : OP_XOR
'#' number
{
597 set_curr_instr
(BPF_ALU | BPF_XOR | BPF_K
, 0, 0, $3); }
599 set_curr_instr
(BPF_ALU | BPF_XOR | BPF_X
, 0, 0, 0); }
601 set_curr_instr
(BPF_ALU | BPF_XOR | BPF_X
, 0, 0, 0); }
605 : OP_LSH
'#' number
{
606 set_curr_instr
(BPF_ALU | BPF_LSH | BPF_K
, 0, 0, $3); }
608 set_curr_instr
(BPF_ALU | BPF_LSH | BPF_X
, 0, 0, 0); }
610 set_curr_instr
(BPF_ALU | BPF_LSH | BPF_X
, 0, 0, 0); }
614 : OP_RSH
'#' number
{
615 set_curr_instr
(BPF_ALU | BPF_RSH | BPF_K
, 0, 0, $3); }
617 set_curr_instr
(BPF_ALU | BPF_RSH | BPF_X
, 0, 0, 0); }
619 set_curr_instr
(BPF_ALU | BPF_RSH | BPF_X
, 0, 0, 0); }
624 set_curr_instr
(BPF_RET | BPF_A
, 0, 0, 0); }
626 set_curr_instr
(BPF_RET | BPF_A
, 0, 0, 0); }
628 set_curr_instr
(BPF_RET | BPF_X
, 0, 0, 0); }
630 set_curr_instr
(BPF_RET | BPF_X
, 0, 0, 0); }
631 | OP_RET
'#' number
{
632 set_curr_instr
(BPF_RET | BPF_K
, 0, 0, $3); }
637 set_curr_instr
(BPF_MISC | BPF_TAX
, 0, 0, 0); }
642 set_curr_instr
(BPF_MISC | BPF_TXA
, 0, 0, 0); }
647 static void stage_1_inline
(void)
652 static void stage_2_label_reduce
(void)
654 int i
, max
= curr_instr
, off
;
656 /* 1. reduce k jumps */
657 for
(i
= 0; i
< max
; ++i
) {
658 if
(labels_k
[i
] != NULL
) {
659 off
= find_intr_offset_or_panic
(labels_k
[i
]);
660 out
[i
].k
= (uint32_t) (off
- i
- 1);
664 /* 1. reduce jt jumps */
665 for
(i
= 0; i
< max
; ++i
) {
666 if
(labels_jt
[i
] != NULL
) {
667 off
= find_intr_offset_or_panic
(labels_jt
[i
]);
668 out
[i
].jt
= (uint8_t) (off
- i
-1);
672 /* 1. reduce jf jumps */
673 for
(i
= 0; i
< max
; ++i
) {
674 if
(labels_jf
[i
] != NULL
) {
675 off
= find_intr_offset_or_panic
(labels_jf
[i
]);
676 out
[i
].jf
= (uint8_t) (off
- i
- 1);
681 static void pretty_printer_c
(const struct sock_fprog
*prog
)
685 for
(i
= 0; i
< prog
->len
; ++i
) {
686 printf
("{ 0x%x, %u, %u, 0x%08x },\n",
687 prog
->filter
[i
].code
, prog
->filter
[i
].jt
,
688 prog
->filter
[i
].jf
, prog
->filter
[i
].k
);
692 static void pretty_printer_xt_bpf
(const struct sock_fprog
*prog
)
696 printf
("%d,", prog
->len
);
697 for
(i
= 0; i
< prog
->len
; ++i
) {
698 printf
("%u %u %u %u,",
699 prog
->filter
[i
].code
, prog
->filter
[i
].jt
,
700 prog
->filter
[i
].jf
, prog
->filter
[i
].k
);
706 static void pretty_printer_tcpdump
(const struct sock_fprog
*prog
)
710 for
(i
= 0; i
< prog
->len
; ++i
) {
711 printf
("%u %u %u %u\n",
712 prog
->filter
[i
].code
, prog
->filter
[i
].jt
,
713 prog
->filter
[i
].jf
, prog
->filter
[i
].k
);
717 static void pretty_printer
(const struct sock_fprog
*prog
, int format
)
721 pretty_printer_c
(prog
);
724 pretty_printer_xt_bpf
(prog
);
727 pretty_printer_tcpdump
(prog
);
734 int compile_filter
(char *file
, bool verbose
, int bypass
, int format
,
735 bool invoke_cpp
, char *const cpp_argv
[])
738 struct sock_fprog res
;
742 memset
(tmp_file
, 0, sizeof
(tmp_file
));
745 ret
= cpp_exec
(file
, tmp_file
, sizeof
(tmp_file
), cpp_argv
);
747 fprintf
(stderr
, "Failed to invoke C preprocessor!\n");
754 if
(!strncmp
("-", file
, strlen
("-")))
757 yyin
= fopen
(file
, "r");
759 panic
("Cannot open file!\n");
761 memset
(out
, 0, sizeof
(out
));
762 memset
(labels
, 0, sizeof
(labels
));
763 memset
(labels_jf
, 0, sizeof
(labels_jf
));
764 memset
(labels_jt
, 0, sizeof
(labels_jt
));
765 memset
(labels_k
, 0, sizeof
(labels_k
));
768 stage_2_label_reduce
();
771 res.len
= curr_instr
;
774 printf
("Generated program:\n");
780 printf
("Validating: ");
784 if
(__bpf_validate
(&res
) == 0) {
786 printf
("Semantic error! BPF validation failed!\n");
788 printf
("Semantic error! BPF validation failed! "
789 "Try -V for debugging output!\n");
793 } else if
(verbose
) {
794 printf
("is runnable!\n");
801 pretty_printer
(&res
, format
);
803 for
(i
= 0; i
< res.len
; ++i
) {
810 if
(yyin
&& yyin
!= stdin
)
820 void yyerror(const char *err
)
822 panic
("Syntax error at line %d: %s! %s!\n",
823 yylineno
, yytext
, err
);