-
Notifications
You must be signed in to change notification settings - Fork 1.6k
/
Copy pathre.c
3462 lines (2912 loc) · 120 KB
/
re.c
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
/*
* ModSecurity for Apache 2.x, http://www.modsecurity.org/
* Copyright (c) 2004-2013 Trustwave Holdings, Inc. (http://www.trustwave.com/)
*
* You may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* If any of the files related to licensing are missing or if you have any
* other questions related to licensing please contact Trustwave Holdings, Inc.
* directly using the email address [email protected].
*/
#include <ctype.h>
#include "re.h"
#if defined(WITH_LUA)
#include "msc_lua.h"
#endif
#ifdef APLOG_USE_MODULE
APLOG_USE_MODULE(security2);
#endif
static const char *const severities[] = {
"EMERGENCY",
"ALERT",
"CRITICAL",
"ERROR",
"WARNING",
"NOTICE",
"INFO",
"DEBUG",
NULL,
};
static int fetch_target_exception(msre_rule *rule, modsec_rec *msr, msre_var *var, const char *exceptions);
static apr_status_t msre_parse_targets(msre_ruleset *ruleset, const char *text,
apr_array_header_t *arr, char **error_msg);
static char *msre_generate_target_string(apr_pool_t *pool, msre_rule *rule);
static msre_var *msre_create_var(msre_ruleset *ruleset, const char *name, const char *param,
modsec_rec *msr, char **error_msg);
static msre_action *msre_create_action(msre_engine *engine, apr_pool_t *mp, const char *name,
const char *param, char **error_msg);
static apr_status_t msre_rule_process(msre_rule *rule, modsec_rec *msr);
/* -- Actions, variables, functions and operator functions ----------------- */
/**
* \brief Remove rule targets to be processed
*
* \param rule Pointer to the rule
* \param msr ModSecurity transaction resource
* \param var Pointer to target structure.
* \param targets Exception list.
*/
static int fetch_target_exception(msre_rule *rule, modsec_rec *msr, msre_var *var, const char *exceptions) {
const char *targets = NULL;
char *savedptr = NULL, *target = NULL;
char *c = NULL, *name = NULL, *value = NULL;
char *variable = NULL, *myvar = NULL;
char *myvalue = NULL, *myname = NULL;
msc_regex_t *regex;
char *errptr;
int erroffset;
int match = 0;
size_t value_len;
if(msr == NULL)
return 0;
if(var == NULL)
return 0;
if(rule == NULL)
return 0;
if(rule->actionset == NULL)
return 0;
if(rule->actionset->id !=NULL) {
myvar = apr_pstrdup(msr->mp, var->name);
c = strchr(myvar,':');
if(c != NULL) {
myname = apr_strtok(myvar,":",&myvalue);
} else {
myname = myvar;
}
match = 0;
targets = apr_pstrdup(msr->mp, exceptions);
if(targets != NULL) {
if (msr->txcfg->debuglog_level >= 9) {
msr_log(msr, 9, "fetch_target_exception: Found exception target list [%s] for rule id %s", targets, rule->actionset->id);
}
target = apr_strtok((char *)targets, ",", &savedptr);
while(target != NULL) {
variable = apr_pstrdup(msr->mp, target);
c = strchr(variable,':');
if(c != NULL) {
name = apr_strtok(variable,":",&value);
} else {
name = variable;
value = NULL;
}
value_len = 0;
if (value != NULL) {
value_len = strlen(value);
}
if((strlen(myname) == strlen(name)) &&
(strncasecmp(myname, name, strlen(myname)) == 0)) {
if(value != NULL && myvalue != NULL) {
if(value_len > 2 && value[0] == '/' && value[value_len - 1] == '/') {
value[value_len - 1] = '\0';
#ifdef WITH_PCRE2
regex = msc_pregcomp(msr->mp, value + 1,
PCRE2_DOTALL | PCRE2_CASELESS | PCRE2_DOLLAR_ENDONLY, (const char **)&errptr, &erroffset);
#else
regex = msc_pregcomp(msr->mp, value + 1,
PCRE_DOTALL | PCRE_CASELESS | PCRE_DOLLAR_ENDONLY, (const char **)&errptr, &erroffset);
#endif
if (regex == NULL) {
if (msr->txcfg->debuglog_level >= 9) {
#ifdef WITH_PCRE2
// in case of PCRE2 the errptr won't fill
msr_log(msr, 9, "fetch_target_exception: Regexp /%s/ failed to compile at pos %d.",
value + 1, erroffset);
ap_log_error(APLOG_MARK, APLOG_ERR, 0, NULL, " ModSecurity: exclusion regexp /%s/ failed to compile at pos %d.",
value + 1, erroffset);
#else
msr_log(msr, 9, "fetch_target_exception: Regexp /%s/ failed to compile at pos %d: %s.",
value + 1, erroffset, errptr);
ap_log_error(APLOG_MARK, APLOG_ERR, 0, NULL, " ModSecurity: exclusion regexp /%s/ failed to compile at pos %d: %s.",
value + 1, erroffset, errptr);
#endif
}
} else {
#ifdef WITH_PCRE2
if (!(msc_regexec(regex, myvalue, strlen(myvalue), &errptr) == PCRE2_ERROR_NOMATCH)) {
#else
if (!(msc_regexec(regex, myvalue, strlen(myvalue), &errptr) == PCRE_ERROR_NOMATCH)) {
#endif
if (msr->txcfg->debuglog_level >= 9) {
msr_log(msr, 9, "fetch_target_exception: Target %s will not be processed.", var->name);
}
match = 1;
}
}
} else if((strlen(myvalue) == value_len) &&
strncasecmp(myvalue,value,strlen(myvalue)) == 0) {
if (msr->txcfg->debuglog_level >= 9) {
msr_log(msr, 9, "fetch_target_exception: Target %s will not be processed.", target);
}
match = 1;
}
} else {
if (msr->txcfg->debuglog_level >= 9) {
msr_log(msr, 9, "fetch_target_exception: Target %s will not be processed.", target);
}
match = 1;
}
}
target = apr_strtok(NULL, ",", &savedptr);
}
} else {
if (msr->txcfg->debuglog_level >= 9) {
msr_log(msr, 9, "fetch_target_exception: No exception target found for rule id %s.", rule->actionset->id);
}
}
}
if(match == 1)
return 1;
return 0;
}
/**
* \brief Update target for all matching rules in set, in any phase
*
* \param msr ModSecurity transaction resource
* \param ruleset Pointer to set of rules to modify
* \param re Pointer to exception object describing which rules to modify
* \param p2 Pointer to configuration option TARGET
* \param p3 Pointer to configuration option REPLACED_TARGET
*/
char *msre_ruleset_rule_update_target_matching_exception(modsec_rec *msr, msre_ruleset *ruleset, rule_exception *re, const char *p2, const char *p3) {
char *err;
if(ruleset == NULL)
return NULL;
if(p2 == NULL) {
return apr_psprintf(ruleset->mp, "Trying to update without a target");
}
if (NULL != (err = msre_ruleset_phase_rule_update_target_matching_exception(msr, ruleset, re, ruleset->phase_request_headers, p2, p3)))
return err;
if (NULL != (err = msre_ruleset_phase_rule_update_target_matching_exception(msr, ruleset, re, ruleset->phase_request_body, p2, p3)))
return err;
if (NULL != (err = msre_ruleset_phase_rule_update_target_matching_exception(msr, ruleset, re, ruleset->phase_response_headers, p2, p3)))
return err;
if (NULL != (err = msre_ruleset_phase_rule_update_target_matching_exception(msr, ruleset, re, ruleset->phase_response_body, p2, p3)))
return err;
if (NULL != (err = msre_ruleset_phase_rule_update_target_matching_exception(msr, ruleset, re, ruleset->phase_logging, p2, p3)))
return err;
/* Everything worked! */
return NULL;
}
/**
* \brief Update target for all matching rules in set for a specific phase
*
* \param msr ModSecurity transaction resource
* \param ruleset Pointer to set of rules to modify
* \param re Pointer to exception object describing which rules to modify
* \param phase_arr Pointer to phase that should be edited
* \param p2 Pointer to configuration option TARGET
* \param p3 Pointer to configuration option REPLACED_TARGET
*
* \todo Figure out error checking
*/
char *msre_ruleset_phase_rule_update_target_matching_exception(modsec_rec *msr, msre_ruleset *ruleset, rule_exception *re,
apr_array_header_t *phase_arr, const char *p2,
const char *p3)
{
msre_rule **rules;
int i, j, mode;
char *err;
j = 0;
mode = 0;
rules = (msre_rule **)phase_arr->elts;
for (i = 0; i < phase_arr->nelts; i++) {
msre_rule *rule = (msre_rule *)rules[i];
if (mode == 0) { /* Looking for next rule. */
if (msre_ruleset_rule_matches_exception(rule, re)) {
err = update_rule_target_ex(NULL, ruleset, rule, p2, p3);
if (err) return err;
if (rule->actionset->is_chained) mode = 2; /* Match all rules in this chain. */
} else {
if (rule->actionset->is_chained) mode = 1; /* Skip all rules in this chain. */
}
} else { /* Handling rule that is part of a chain. */
if (mode == 2) { /* We want to change the rule. */
err = update_rule_target_ex(msr, ruleset, rule, p2, p3);
if (err) return err;
}
if ((rule->actionset == NULL)||(rule->actionset->is_chained == 0)) mode = 0;
}
}
return NULL;
}
char *update_rule_target_ex(modsec_rec *msr, msre_ruleset *ruleset, msre_rule *rule, const char *p2,
const char *p3) {
msre_var **targets = NULL;
const char *current_targets = NULL;
char *my_error_msg = NULL, *target = NULL;
char *p = NULL, *savedptr = NULL;
unsigned int is_negated = 0, is_counting = 0;
int name_len = 0, value_len = 0;
char *name = NULL, *value = NULL;
char *opt = NULL, *param = NULL;
char *target_list = NULL, *replace = NULL;
int i, rc, match = 0, var_appended = 0;
if(rule != NULL) {
target_list = strdup(p2);
if(target_list == NULL)
return apr_psprintf(ruleset->mp, "Error to update target - memory allocation");;
if(p3 != NULL) {
replace = strdup(p3);
if(replace == NULL) {
free(target_list);
target_list = NULL;
return apr_psprintf(ruleset->mp, "Error to update target - memory allocation");;
}
}
if(replace != NULL) {
opt = strchr(replace,'!');
if(opt != NULL) {
*opt = '\0';
opt++;
param = opt;
is_negated = 1;
} else if ((opt = strchr(replace,'&')) != NULL) {
*opt = '\0';
opt++;
param = opt;
is_counting = 1;
} else {
param = replace;
}
opt = strchr(param,':');
if(opt != NULL) {
name = apr_strtok(param,":",&value);
} else {
name = param;
}
if(apr_table_get(ruleset->engine->variables, name) == NULL) {
if(target_list != NULL)
free(target_list);
if(replace != NULL)
free(replace);
if(msr) {
msr_log(msr, 9, "Error to update target - [%s] is not valid target", name);
}
return apr_psprintf(ruleset->mp, "Error to update target - [%s] is not valid target", name);
}
name_len = strlen(name);
if(value != NULL)
value_len = strlen(value);
if(msr) {
msr_log(msr, 9, "Trying to replace by variable name [%s] value [%s]", name, value);
}
#if !defined(MSC_TEST)
else {
ap_log_error(APLOG_MARK, APLOG_INFO, 0, NULL, " ModSecurity: Trying to replace by variable name [%s] value [%s]", name, value);
}
#endif
targets = (msre_var **)rule->targets->elts;
// TODO need a good way to remove the element from array, maybe change array by tables or rings
for (i = 0; i < rule->targets->nelts; i++) {
if((strlen(targets[i]->name) == strlen(name)) &&
(strncasecmp(targets[i]->name,name,strlen(targets[i]->name)) == 0) &&
(targets[i]->is_negated == is_negated) &&
(targets[i]->is_counting == is_counting)) {
if(value != NULL && targets[i]->param != NULL) {
if((strlen(targets[i]->param) == strlen(value)) &&
strncasecmp(targets[i]->param,value,strlen(targets[i]->param)) == 0) {
memset(targets[i]->name,0,strlen(targets[i]->name));
memset(targets[i]->param,0,strlen(targets[i]->param));
targets[i]->is_counting = 0;
targets[i]->is_negated = 1;
match = 1;
}
} else if (value == NULL && targets[i]->param == NULL){
memset(targets[i]->name,0,strlen(targets[i]->name));
targets[i]->is_counting = 0;
targets[i]->is_negated = 1;
match = 1;
} else
continue;
}
}
}
p = apr_strtok(target_list, ",", &savedptr);
while(p != NULL) {
if(replace != NULL) {
if(match == 1) {
rc = msre_parse_targets(ruleset, p, rule->targets, &my_error_msg);
if (rc < 0) {
if(msr) {
msr_log(msr, 9, "Error parsing rule targets to replace variable");
}
#if !defined(MSC_TEST)
else {
ap_log_error(APLOG_MARK, APLOG_ERR, 0, NULL, " ModSecurity: Error parsing rule targets to replace variable");
}
#endif
goto end;
}
if(msr) {
msr_log(msr, 9, "Successfully replaced variable");
}
#if !defined(MSC_TEST)
else {
ap_log_error(APLOG_MARK, APLOG_INFO, 0, NULL, " ModSecurity: Successfully replaced variable");
}
#endif
var_appended = 1;
} else {
if(msr) {
msr_log(msr, 9, "Cannot find variable to replace");
}
#if !defined(MSC_TEST)
else {
ap_log_error(APLOG_MARK, APLOG_ERR, 0, NULL, " ModSecurity: Cannot find varibale to replace");
}
#endif
goto end;
}
} else {
target = strdup(p);
if(target == NULL)
return NULL;
is_negated = is_counting = 0;
param = name = value = NULL;
opt = strchr(target,'!');
if(opt != NULL) {
*opt = '\0';
opt++;
param = opt;
is_negated = 1;
} else if ((opt = strchr(target,'&')) != NULL) {
*opt = '\0';
opt++;
param = opt;
is_counting = 1;
} else {
param = target;
}
opt = strchr(param,':');
if(opt != NULL) {
name = apr_strtok(param,":",&value);
} else {
name = param;
}
if(apr_table_get(ruleset->engine->variables, name) == NULL) {
if(target_list != NULL)
free(target_list);
if(replace != NULL)
free(replace);
if(msr) {
msr_log(msr, 9, "Error to update target - [%s] is not valid target", name);
}
return apr_psprintf(ruleset->mp, "Error to update target - [%s] is not valid target", name);
}
name_len = strlen(name);
if(value != NULL)
value_len = strlen(value);
if(msr) {
msr_log(msr, 9, "Trying to append variable name [%s] value [%s]", name, value);
}
#if !defined(MSC_TEST)
else {
ap_log_error(APLOG_MARK, APLOG_INFO, 0, NULL, " ModSecurity: Trying to append variable name [%s] value [%s]", name, value);
}
#endif
match = 0;
targets = (msre_var **)rule->targets->elts;
for (i = 0; i < rule->targets->nelts; i++) {
if((strlen(targets[i]->name) == strlen(name)) &&
(strncasecmp(targets[i]->name,name,strlen(targets[i]->name)) == 0) &&
(targets[i]->is_negated == is_negated) &&
(targets[i]->is_counting == is_counting)) {
if(value != NULL && targets[i]->param != NULL) {
if((strlen(targets[i]->param) == strlen(value)) &&
strncasecmp(targets[i]->param,value,strlen(targets[i]->param)) == 0) {
match = 1;
}
} else if (value == NULL && targets[i]->param == NULL){
match = 1;
} else
continue;
}
}
if(target != NULL) {
free(target);
target = NULL;
}
if(match == 0 ) {
rc = msre_parse_targets(ruleset, p, rule->targets, &my_error_msg);
if (rc < 0) {
if(msr) {
msr_log(msr, 9, "Error parsing rule targets to append variable");
}
#if !defined(MSC_TEST)
else {
ap_log_error(APLOG_MARK, APLOG_ERR, 0, NULL, " ModSecurity: Error parsing rule targets to append variable");
}
#endif
goto end;
}
var_appended = 1;
} else {
if(msr) {
msr_log(msr, 9, "Skipping variable, already appended");
}
#if !defined(MSC_TEST)
else {
ap_log_error(APLOG_MARK, APLOG_INFO, 0, NULL, " ModSecurity: Skipping variable, already appended");
}
#endif
}
}
p = apr_strtok(NULL,",",&savedptr);
}
if(var_appended == 1) {
current_targets = msre_generate_target_string(ruleset->mp, rule);
rule->unparsed = msre_rule_generate_unparsed(ruleset->mp, rule, current_targets, NULL, NULL);
rule->p1 = apr_pstrdup(ruleset->mp, current_targets);
if(msr) {
msr_log(msr, 9, "Successfully appended variable");
}
#if !defined(MSC_TEST)
else {
ap_log_error(APLOG_MARK, APLOG_INFO, 0, NULL, " ModSecurity: Successfully appended variable");
}
#endif
}
}
end:
if(target_list != NULL) {
free(target_list);
target_list = NULL;
}
if(replace != NULL) {
free(replace);
replace = NULL;
}
if(target != NULL) {
free(target);
target = NULL;
}
return NULL;
}
int msre_ruleset_rule_matches_exception(msre_rule *rule, rule_exception *re) {
int match = 0;
/* Only remove non-placeholder rules */
if (rule->placeholder == RULE_PH_NONE) {
switch(re->type) {
case RULE_EXCEPTION_REMOVE_ID :
if ((rule->actionset != NULL)&&(rule->actionset->id != NULL)) {
int ruleid = atoi(rule->actionset->id);
if (rule_id_in_range(ruleid, re->param)) {
match = 1;
}
}
break;
case RULE_EXCEPTION_REMOVE_MSG :
if ((rule->actionset != NULL)&&(rule->actionset->msg != NULL)) {
char *my_error_msg = NULL;
int rc = msc_regexec(re->param_data,
rule->actionset->msg, strlen(rule->actionset->msg),
&my_error_msg);
if (rc >= 0) {
match = 1;
}
}
break;
case RULE_EXCEPTION_REMOVE_TAG :
if ((rule->actionset != NULL)&&(apr_is_empty_table(rule->actionset->actions) == 0)) {
char *my_error_msg = NULL;
const apr_array_header_t *tarr = NULL;
const apr_table_entry_t *telts = NULL;
int act;
tarr = apr_table_elts(rule->actionset->actions);
telts = (const apr_table_entry_t*)tarr->elts;
for (act = 0; act < tarr->nelts; act++) {
msre_action *action = (msre_action *)telts[act].val;
if((action != NULL) && (action->metadata != NULL) && (strcmp("tag", action->metadata->name) == 0)) {
int rc = msc_regexec(re->param_data,
action->param, strlen(action->param),
&my_error_msg);
if (rc >= 0) {
match = 1;
}
}
}
}
break;
}
}
return match;
}
/**
* Remove actions with the same cardinality group from the actionset.
*/
static void msre_actionset_cardinality_fixup(msre_actionset *actionset, msre_action *action) {
const apr_array_header_t *tarr = NULL;
const apr_table_entry_t *telts = NULL;
int i;
if ((actionset == NULL) || (action == NULL)) return;
tarr = apr_table_elts(actionset->actions);
telts = (const apr_table_entry_t*)tarr->elts;
for (i = 0; i < tarr->nelts; i++) {
msre_action *target = (msre_action *)telts[i].val;
if (target->metadata->cardinality_group == action->metadata->cardinality_group) {
apr_table_unset(actionset->actions, target->metadata->name);
}
}
}
static char *msre_generate_target_string(apr_pool_t *pool, msre_rule *rule) {
char *target_str = NULL;
msre_var **targets = NULL;
int i = 0;
targets = (msre_var **)rule->targets->elts;
for (i = 0; i < rule->targets->nelts; i++) {
if(targets[i]->name != NULL && strlen(targets[i]->name) > 0) {
target_str = apr_pstrcat(pool,
(target_str == NULL) ? "" : apr_psprintf(pool, "%s|", target_str),
(targets[i]->is_negated == 0) ? "" : "!",
(targets[i]->is_counting == 0) ? "" : "&",
(targets[i]->name == NULL) ? "" : targets[i]->name,
(targets[i]->param == NULL) ? "" : apr_psprintf(pool, ":%s", targets[i]->param),
NULL);
}
}
return target_str;
}
/**
* Generate an action string from an actionset.
*/
static char *msre_actionset_generate_action_string(apr_pool_t *pool, const msre_actionset *actionset) {
const apr_array_header_t *tarr = NULL;
const apr_table_entry_t *telts = NULL;
char *actions = NULL;
int chain;
int i;
if (actionset == NULL) return NULL;
chain = ((actionset->rule != NOT_SET_P) && actionset->rule->chain_starter) ? 1 : 0;
tarr = apr_table_elts(actionset->actions);
telts = (const apr_table_entry_t*)tarr->elts;
for (i = 0; i < tarr->nelts; i++) {
msre_action *action = (msre_action *)telts[i].val;
int use_quotes = 0;
if (chain) {
/* Skip some actions that are not used in a chain. */
if ( (action->metadata->type == ACTION_DISRUPTIVE)
|| (action->metadata->type == ACTION_METADATA)
|| (strcmp("log", action->metadata->name) == 0)
|| (strcmp("auditlog", action->metadata->name) == 0)
|| (strcmp("nolog", action->metadata->name) == 0)
|| (strcmp("noauditlog", action->metadata->name) == 0)
|| (strcmp("severity", action->metadata->name) == 0)
|| (strcmp("ver", action->metadata->name) == 0)
|| (strcmp("maturity", action->metadata->name) == 0)
|| (strcmp("accuracy", action->metadata->name) == 0)
|| (strcmp("tag", action->metadata->name) == 0)
|| (strcmp("phase", action->metadata->name) == 0))
{
continue;
}
}
/* Check if we need any quotes */
if (action->param != NULL) {
int j;
for(j = 0; action->param[j] != '\0'; j++) {
if (isspace(action->param[j])) {
use_quotes = 1;
break;
}
}
if (j == 0) use_quotes = 1;
}
actions = apr_pstrcat(pool,
(actions == NULL) ? "" : actions,
(actions == NULL) ? "" : ",",
action->metadata->name,
(action->param == NULL) ? "" : ":",
(use_quotes) ? "'" : "",
(action->param == NULL) ? "" : action->param,
(use_quotes) ? "'" : "",
NULL);
}
return actions;
}
/**
* Add an action to an actionset.
*/
static void msre_actionset_action_add(msre_actionset *actionset, msre_action *action)
{
msre_action *add_action = action;
if ((actionset == NULL)) return;
/**
* The "block" action is just a placeholder for the parent action.
*/
if ((actionset->parent_intercept_action_rec != NULL) && (actionset->parent_intercept_action_rec != NOT_SET_P) && (strcmp("block", action->metadata->name) == 0) && (strcmp("block", action->metadata->name) == 0)) {
/* revert back to parent */
actionset->intercept_action = actionset->parent_intercept_action;
add_action = actionset->parent_intercept_action_rec;
}
if ((add_action == NULL)) return;
if (add_action->metadata->cardinality_group != ACTION_CGROUP_NONE) {
msre_actionset_cardinality_fixup(actionset, add_action);
}
if (add_action->metadata->cardinality == ACTION_CARDINALITY_ONE) {
/* One action per actionlist. */
apr_table_setn(actionset->actions, add_action->metadata->name, (void *)add_action);
} else {
/* Multiple actions per actionlist. */
apr_table_addn(actionset->actions, add_action->metadata->name, (void *)add_action);
}
}
/**
* Creates msre_var instances (rule variables) out of the
* given text string and places them into the supplied table.
*/
static apr_status_t msre_parse_targets(msre_ruleset *ruleset, const char *text,
apr_array_header_t *arr, char **error_msg)
{
const apr_array_header_t *tarr;
const apr_table_entry_t *telts;
apr_table_t *vartable;
unsigned int count = 0;
apr_status_t rc;
msre_var *var;
int i;
if (text == NULL) return -1;
/* Extract name & value pairs first */
vartable = apr_table_make(ruleset->mp, 10);
if (vartable == NULL) return -1;
rc = msre_parse_generic(ruleset->mp, text, vartable, error_msg);
if (rc < 0) return rc;
/* Loop through the table and create variables */
tarr = apr_table_elts(vartable);
telts = (const apr_table_entry_t*)tarr->elts;
for (i = 0; i < tarr->nelts; i++) {
var = msre_create_var(ruleset, telts[i].key, telts[i].val, NULL, error_msg);
if (var == NULL) return -1;
*(msre_var **)apr_array_push(arr) = var;
count++;
}
return count;
}
/**
* Creates msre_action instances by parsing the given string, placing
* them into the supplied array.
*/
static apr_status_t msre_parse_actions(msre_engine *engine, apr_pool_t *mp, msre_actionset *actionset,
const char *text, char **error_msg)
{
const apr_array_header_t *tarr;
const apr_table_entry_t *telts;
apr_table_t *vartable;
unsigned int count = 0;
apr_status_t rc;
msre_action *action;
int i;
if (error_msg == NULL) {
return -1;
}
*error_msg = NULL;
if (text == NULL) {
*error_msg = apr_psprintf(mp, "Internal error: " \
"msre_parse_actions, variable text is NULL");
return -1;
}
/* Extract name & value pairs first */
vartable = apr_table_make(mp, 10);
if (vartable == NULL) {
*error_msg = apr_psprintf(mp, "Internal error: " \
"msre_parse_actions, failed to create vartable");
return -1;
}
rc = msre_parse_generic(mp, text, vartable, error_msg);
if (rc < 0) {
if (*error_msg == NULL)
*error_msg = apr_psprintf(mp, "Internal error: " \
"msre_parse_actions, msre_parse_generic failed. Return " \
"code: %d", rc);
return rc;
}
/* Loop through the table and create actions */
tarr = apr_table_elts(vartable);
telts = (const apr_table_entry_t*)tarr->elts;
for (i = 0; i < tarr->nelts; i++) {
/* Create action. */
action = msre_create_action(engine, mp, telts[i].key, telts[i].val, error_msg);
if (action == NULL) {
if (*error_msg == NULL)
*error_msg = apr_psprintf(mp, "Internal error: " \
"msre_parse_actions, msre_create_action failed.");
return -1;
}
/* Initialise action (option). */
if (action->metadata->init != NULL) {
action->metadata->init(engine, mp, actionset, action);
}
msre_actionset_action_add(actionset, action);
count++;
}
return count;
}
/**
* Locates variable metadata given the variable name.
*/
msre_var_metadata *msre_resolve_var(msre_engine *engine, const char *name)
{
return (msre_var_metadata *)apr_table_get(engine->variables, name);
}
/**
* Locates action metadata given the action name.
*/
static msre_action_metadata *msre_resolve_action(msre_engine *engine, const char *name)
{
return (msre_action_metadata *)apr_table_get(engine->actions, name);
}
/**
* Creates a new variable instance given the variable name
* and an (optional) parameter.
*/
msre_var *msre_create_var_ex(apr_pool_t *pool, msre_engine *engine, const char *name, const char *param,
modsec_rec *msr, char **error_msg)
{
const char *varparam = param;
msre_var *var = apr_pcalloc(pool, sizeof(msre_var));
if (var == NULL) return NULL;
if (error_msg == NULL) return NULL;
*error_msg = NULL;
/* Handle negation and member counting */
if (name[0] == '!') {
var->is_negated = 1;
var->name = (char *)name + 1;
}
else
if (name[0] == '&') {
var->is_counting = 1;
var->name = (char *)name + 1;
}
else {
var->name = (char *)name;
}
/* Treat HTTP_* targets as an alias for REQUEST_HEADERS:* */
if ( (var->name != NULL)
&& (strlen(var->name) > 5)
&& (strncmp("HTTP_", var->name, 5) == 0))
{
const char *oldname = var->name;
var->name = apr_pstrdup(pool, "REQUEST_HEADERS");
varparam = apr_pstrdup(pool, oldname + 5);
}
/* Resolve variable */
var->metadata = msre_resolve_var(engine, var->name);
if (var->metadata == NULL) {
*error_msg = apr_psprintf(pool, "Unknown variable: %s", name);
return NULL;
}
/* The counting operator "&" can only be used against collections. */
if (var->is_counting) {
if (var->metadata->type == VAR_SIMPLE) {
*error_msg = apr_psprintf(pool, "The & modificator does not apply to "
"non-collection variables.");
return NULL;
}
}
/* Check the parameter. */
if (varparam == NULL) {
if (var->metadata->argc_min > 0) {
*error_msg = apr_psprintf(pool, "Missing mandatory parameter for variable %s.",
name);
return NULL;
}
} else { /* Parameter present */
/* Do we allow a parameter? */
if (var->metadata->argc_max == 0) {
*error_msg = apr_psprintf(pool, "Variable %s does not support parameters.",
name);
return NULL;
}
var->param = (char *)varparam;
}
return var;
}
/**
* Create a new variable object from the provided name and value.
*
* NOTE: this allocates out of the global pool and should not be used
* per-request
*/
static msre_var *msre_create_var(msre_ruleset *ruleset, const char *name, const char *param,
modsec_rec *msr, char **error_msg)
{
msre_var *var = msre_create_var_ex(ruleset->mp, ruleset->engine, name, param, msr, error_msg);
if (var == NULL) return NULL;
/* Validate & initialise variable */
if (var->metadata->validate != NULL) {
*error_msg = var->metadata->validate(ruleset, var);
if (*error_msg != NULL) {
return NULL;
}
}
return var;
}