-
Notifications
You must be signed in to change notification settings - Fork 3.8k
/
verify.c
6441 lines (5445 loc) · 203 KB
/
verify.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
/*
* verify.c:
*
* Author:
* Mono Project (http://www.mono-project.com)
*
* Copyright 2001-2003 Ximian, Inc (http://www.ximian.com)
* Copyright 2004-2009 Novell, Inc (http://www.novell.com)
* Copyright 2011 Rodrigo Kumpera
*/
#include <config.h>
#include <mono/metadata/object-internals.h>
#include <mono/metadata/verify.h>
#include <mono/metadata/verify-internals.h>
#include <mono/metadata/opcodes.h>
#include <mono/metadata/tabledefs.h>
#include <mono/metadata/reflection.h>
#include <mono/metadata/debug-helpers.h>
#include <mono/metadata/mono-endian.h>
#include <mono/metadata/metadata.h>
#include <mono/metadata/metadata-internals.h>
#include <mono/metadata/class-internals.h>
#include <mono/metadata/security-manager.h>
#include <mono/metadata/security-core-clr.h>
#include <mono/metadata/tokentype.h>
#include <mono/metadata/mono-basic-block.h>
#include <mono/metadata/attrdefs.h>
#include <mono/metadata/class-internals.h>
#include <mono/utils/mono-counters.h>
#include <mono/utils/monobitset.h>
#include <string.h>
#include <ctype.h>
static MiniVerifierMode verifier_mode = MONO_VERIFIER_MODE_OFF;
static gboolean verify_all = FALSE;
/*
* Set the desired level of checks for the verfier.
*
*/
void
mono_verifier_set_mode (MiniVerifierMode mode)
{
verifier_mode = mode;
}
void
mono_verifier_enable_verify_all ()
{
verify_all = TRUE;
}
#ifndef DISABLE_VERIFIER
/*
* Pull the list of opcodes
*/
#define OPDEF(a,b,c,d,e,f,g,h,i,j) \
a = i,
enum {
#include "mono/cil/opcode.def"
LAST = 0xff
};
#undef OPDEF
#ifdef MONO_VERIFIER_DEBUG
#define VERIFIER_DEBUG(code) do { code } while (0)
#else
#define VERIFIER_DEBUG(code)
#endif
//////////////////////////////////////////////////////////////////
#define IS_STRICT_MODE(ctx) (((ctx)->level & MONO_VERIFY_NON_STRICT) == 0)
#define IS_FAIL_FAST_MODE(ctx) (((ctx)->level & MONO_VERIFY_FAIL_FAST) == MONO_VERIFY_FAIL_FAST)
#define IS_SKIP_VISIBILITY(ctx) (((ctx)->level & MONO_VERIFY_SKIP_VISIBILITY) == MONO_VERIFY_SKIP_VISIBILITY)
#define IS_REPORT_ALL_ERRORS(ctx) (((ctx)->level & MONO_VERIFY_REPORT_ALL_ERRORS) == MONO_VERIFY_REPORT_ALL_ERRORS)
#define CLEAR_PREFIX(ctx, prefix) do { (ctx)->prefix_set &= ~(prefix); } while (0)
#define ADD_VERIFY_INFO(__ctx, __msg, __status, __exception) \
do { \
MonoVerifyInfoExtended *vinfo = g_new (MonoVerifyInfoExtended, 1); \
vinfo->info.status = __status; \
vinfo->info.message = ( __msg ); \
vinfo->exception_type = (__exception); \
(__ctx)->list = g_slist_prepend ((__ctx)->list, vinfo); \
} while (0)
//TODO support MONO_VERIFY_REPORT_ALL_ERRORS
#define ADD_VERIFY_ERROR(__ctx, __msg) \
do { \
ADD_VERIFY_INFO(__ctx, __msg, MONO_VERIFY_ERROR, MONO_EXCEPTION_INVALID_PROGRAM); \
(__ctx)->valid = 0; \
} while (0)
#define CODE_NOT_VERIFIABLE(__ctx, __msg) \
do { \
if ((__ctx)->verifiable || IS_REPORT_ALL_ERRORS (__ctx)) { \
ADD_VERIFY_INFO(__ctx, __msg, MONO_VERIFY_NOT_VERIFIABLE, MONO_EXCEPTION_UNVERIFIABLE_IL); \
(__ctx)->verifiable = 0; \
if (IS_FAIL_FAST_MODE (__ctx)) \
(__ctx)->valid = 0; \
} \
} while (0)
#define ADD_VERIFY_ERROR2(__ctx, __msg, __exception) \
do { \
ADD_VERIFY_INFO(__ctx, __msg, MONO_VERIFY_ERROR, __exception); \
(__ctx)->valid = 0; \
} while (0)
#define CODE_NOT_VERIFIABLE2(__ctx, __msg, __exception) \
do { \
if ((__ctx)->verifiable || IS_REPORT_ALL_ERRORS (__ctx)) { \
ADD_VERIFY_INFO(__ctx, __msg, MONO_VERIFY_NOT_VERIFIABLE, __exception); \
(__ctx)->verifiable = 0; \
if (IS_FAIL_FAST_MODE (__ctx)) \
(__ctx)->valid = 0; \
} \
} while (0)
#define CHECK_ADD4_OVERFLOW_UN(a, b) ((guint32)(0xFFFFFFFFU) - (guint32)(b) < (guint32)(a))
#define CHECK_ADD8_OVERFLOW_UN(a, b) ((guint64)(0xFFFFFFFFFFFFFFFFUL) - (guint64)(b) < (guint64)(a))
#if SIZEOF_VOID_P == 4
#define CHECK_ADDP_OVERFLOW_UN(a,b) CHECK_ADD4_OVERFLOW_UN(a, b)
#else
#define CHECK_ADDP_OVERFLOW_UN(a,b) CHECK_ADD8_OVERFLOW_UN(a, b)
#endif
#define ADDP_IS_GREATER_OR_OVF(a, b, c) (((a) + (b) > (c)) || CHECK_ADDP_OVERFLOW_UN (a, b))
#define ADD_IS_GREATER_OR_OVF(a, b, c) (((a) + (b) > (c)) || CHECK_ADD4_OVERFLOW_UN (a, b))
/*Flags to be used with ILCodeDesc::flags */
enum {
/*Instruction has not been processed.*/
IL_CODE_FLAG_NOT_PROCESSED = 0,
/*Instruction was decoded by mono_method_verify loop.*/
IL_CODE_FLAG_SEEN = 1,
/*Instruction was target of a branch or is at a protected block boundary.*/
IL_CODE_FLAG_WAS_TARGET = 2,
/*Used by stack_init to avoid double initialize each entry.*/
IL_CODE_FLAG_STACK_INITED = 4,
/*Used by merge_stacks to decide if it should just copy the eval stack.*/
IL_CODE_STACK_MERGED = 8,
/*This instruction is part of the delegate construction sequence, it cannot be target of a branch.*/
IL_CODE_DELEGATE_SEQUENCE = 0x10,
/*This is a delegate created from a ldftn to a non final virtual method*/
IL_CODE_LDFTN_DELEGATE_NONFINAL_VIRTUAL = 0x20,
/*This is a call to a non final virtual method*/
IL_CODE_CALL_NONFINAL_VIRTUAL = 0x40,
};
typedef enum {
RESULT_VALID,
RESULT_UNVERIFIABLE,
RESULT_INVALID
} verify_result_t;
typedef struct {
MonoType *type;
int stype;
MonoMethod *method;
} ILStackDesc;
typedef struct {
ILStackDesc *stack;
guint16 size, max_size;
guint16 flags;
} ILCodeDesc;
typedef struct {
int max_args;
int max_stack;
int verifiable;
int valid;
int level;
int code_size;
ILCodeDesc *code;
ILCodeDesc eval;
MonoType **params;
GSList *list;
/*Allocated fnptr MonoType that should be freed by us.*/
GSList *funptrs;
/*Type dup'ed exception types from catch blocks.*/
GSList *exception_types;
int num_locals;
MonoType **locals;
/*TODO get rid of target here, need_merge in mono_method_verify and hoist the merging code in the branching code*/
int target;
guint32 ip_offset;
MonoMethodSignature *signature;
MonoMethodHeader *header;
MonoGenericContext *generic_context;
MonoImage *image;
MonoMethod *method;
/*This flag helps solving a corner case of delegate verification in that you cannot have a "starg 0"
*on a method that creates a delegate for a non-final virtual method using ldftn*/
gboolean has_this_store;
/*This flag is used to control if the contructor of the parent class has been called.
*If the this pointer is pushed on the eval stack and it's a reference type constructor and
* super_ctor_called is false, the uninitialized flag is set on the pushed value.
*
* Poping an uninitialized this ptr from the eval stack is an unverifiable operation unless
* the safe variant is used. Only a few opcodes can use it : dup, pop, ldfld, stfld and call to a constructor.
*/
gboolean super_ctor_called;
guint32 prefix_set;
gboolean has_flags;
MonoType *constrained_type;
} VerifyContext;
static void
merge_stacks (VerifyContext *ctx, ILCodeDesc *from, ILCodeDesc *to, gboolean start, gboolean external);
static int
get_stack_type (MonoType *type);
static gboolean
mono_delegate_signature_equal (MonoMethodSignature *delegate_sig, MonoMethodSignature *method_sig, gboolean is_static_ldftn);
static gboolean
mono_class_is_valid_generic_instantiation (VerifyContext *ctx, MonoClass *klass);
static gboolean
mono_method_is_valid_generic_instantiation (VerifyContext *ctx, MonoMethod *method);
static MonoGenericParam*
verifier_get_generic_param_from_type (VerifyContext *ctx, MonoType *type);
static gboolean
verifier_class_is_assignable_from (MonoClass *target, MonoClass *candidate);
//////////////////////////////////////////////////////////////////
enum {
TYPE_INV = 0, /* leave at 0. */
TYPE_I4 = 1,
TYPE_I8 = 2,
TYPE_NATIVE_INT = 3,
TYPE_R8 = 4,
/* Used by operator tables to resolve pointer types (managed & unmanaged) and by unmanaged pointer types*/
TYPE_PTR = 5,
/* value types and classes */
TYPE_COMPLEX = 6,
/* Number of types, used to define the size of the tables*/
TYPE_MAX = 6,
/* Used by tables to signal that a result is not verifiable*/
NON_VERIFIABLE_RESULT = 0x80,
/*Mask used to extract just the type, excluding flags */
TYPE_MASK = 0x0F,
/* The stack type is a managed pointer, unmask the value to res */
POINTER_MASK = 0x100,
/*Stack type with the pointer mask*/
RAW_TYPE_MASK = 0x10F,
/* Controlled Mutability Manager Pointer */
CMMP_MASK = 0x200,
/* The stack type is a null literal*/
NULL_LITERAL_MASK = 0x400,
/**Used by ldarg.0 and family to let delegate verification happens.*/
THIS_POINTER_MASK = 0x800,
/**Signals that this is a boxed value type*/
BOXED_MASK = 0x1000,
/*This is an unitialized this ref*/
UNINIT_THIS_MASK = 0x2000,
};
static const char* const
type_names [TYPE_MAX + 1] = {
"Invalid",
"Int32",
"Int64",
"Native Int",
"Float64",
"Native Pointer",
"Complex"
};
enum {
PREFIX_UNALIGNED = 1,
PREFIX_VOLATILE = 2,
PREFIX_TAIL = 4,
PREFIX_CONSTRAINED = 8,
PREFIX_READONLY = 16
};
//////////////////////////////////////////////////////////////////
#ifdef ENABLE_VERIFIER_STATS
#define _MEM_ALLOC(amt) do { allocated_memory += (amt); working_set += (amt); } while (0)
#define _MEM_FREE(amt) do { working_set -= (amt); } while (0)
static int allocated_memory;
static int working_set;
static int max_allocated_memory;
static int max_working_set;
static int total_allocated_memory;
static void
finish_collect_stats (void)
{
max_allocated_memory = MAX (max_allocated_memory, allocated_memory);
max_working_set = MAX (max_working_set, working_set);
total_allocated_memory += allocated_memory;
allocated_memory = working_set = 0;
}
static void
init_verifier_stats (void)
{
static gboolean inited;
if (!inited) {
inited = TRUE;
mono_counters_register ("Maximum memory allocated during verification", MONO_COUNTER_METADATA | MONO_COUNTER_INT, &max_allocated_memory);
mono_counters_register ("Maximum memory used during verification", MONO_COUNTER_METADATA | MONO_COUNTER_INT, &max_working_set);
mono_counters_register ("Total memory allocated for verification", MONO_COUNTER_METADATA | MONO_COUNTER_INT, &total_allocated_memory);
}
}
#else
#define _MEM_ALLOC(amt) do {} while (0)
#define _MEM_FREE(amt) do { } while (0)
#define finish_collect_stats()
#define init_verifier_stats()
#endif
//////////////////////////////////////////////////////////////////
/*Token validation macros and functions */
#define IS_MEMBER_REF(token) (mono_metadata_token_table (token) == MONO_TABLE_MEMBERREF)
#define IS_METHOD_DEF(token) (mono_metadata_token_table (token) == MONO_TABLE_METHOD)
#define IS_METHOD_SPEC(token) (mono_metadata_token_table (token) == MONO_TABLE_METHODSPEC)
#define IS_FIELD_DEF(token) (mono_metadata_token_table (token) == MONO_TABLE_FIELD)
#define IS_TYPE_REF(token) (mono_metadata_token_table (token) == MONO_TABLE_TYPEREF)
#define IS_TYPE_DEF(token) (mono_metadata_token_table (token) == MONO_TABLE_TYPEDEF)
#define IS_TYPE_SPEC(token) (mono_metadata_token_table (token) == MONO_TABLE_TYPESPEC)
#define IS_METHOD_DEF_OR_REF_OR_SPEC(token) (IS_METHOD_DEF (token) || IS_MEMBER_REF (token) || IS_METHOD_SPEC (token))
#define IS_TYPE_DEF_OR_REF_OR_SPEC(token) (IS_TYPE_DEF (token) || IS_TYPE_REF (token) || IS_TYPE_SPEC (token))
#define IS_FIELD_DEF_OR_REF(token) (IS_FIELD_DEF (token) || IS_MEMBER_REF (token))
/*
* Verify if @token refers to a valid row on int's table.
*/
static gboolean
token_bounds_check (MonoImage *image, guint32 token)
{
if (image_is_dynamic (image))
return mono_reflection_is_valid_dynamic_token ((MonoDynamicImage*)image, token);
return image->tables [mono_metadata_token_table (token)].rows >= mono_metadata_token_index (token) && mono_metadata_token_index (token) > 0;
}
static MonoType *
mono_type_create_fnptr_from_mono_method (VerifyContext *ctx, MonoMethod *method)
{
MonoType *res = g_new0 (MonoType, 1);
_MEM_ALLOC (sizeof (MonoType));
//FIXME use mono_method_get_signature_full
res->data.method = mono_method_signature (method);
res->type = MONO_TYPE_FNPTR;
ctx->funptrs = g_slist_prepend (ctx->funptrs, res);
return res;
}
/*
* mono_type_is_enum_type:
*
* Returns TRUE if @type is an enum type.
*/
static gboolean
mono_type_is_enum_type (MonoType *type)
{
if (type->type == MONO_TYPE_VALUETYPE && type->data.klass->enumtype)
return TRUE;
if (type->type == MONO_TYPE_GENERICINST && type->data.generic_class->container_class->enumtype)
return TRUE;
return FALSE;
}
/*
* mono_type_is_value_type:
*
* Returns TRUE if @type is named after @namespace.@name.
*
*/
static gboolean
mono_type_is_value_type (MonoType *type, const char *namespace_, const char *name)
{
return type->type == MONO_TYPE_VALUETYPE &&
!strcmp (namespace_, type->data.klass->name_space) &&
!strcmp (name, type->data.klass->name);
}
/*
* Returns TURE if @type is VAR or MVAR
*/
static gboolean
mono_type_is_generic_argument (MonoType *type)
{
return type->type == MONO_TYPE_VAR || type->type == MONO_TYPE_MVAR;
}
/*
* mono_type_get_underlying_type_any:
*
* This functions is just like mono_type_get_underlying_type but it doesn't care if the type is byref.
*
* Returns the underlying type of @type regardless if it is byref or not.
*/
static MonoType*
mono_type_get_underlying_type_any (MonoType *type)
{
if (type->type == MONO_TYPE_VALUETYPE && type->data.klass->enumtype)
return mono_class_enum_basetype (type->data.klass);
if (type->type == MONO_TYPE_GENERICINST && type->data.generic_class->container_class->enumtype)
return mono_class_enum_basetype (type->data.generic_class->container_class);
return type;
}
static G_GNUC_UNUSED const char*
mono_type_get_stack_name (MonoType *type)
{
return type_names [get_stack_type (type) & TYPE_MASK];
}
#define CTOR_REQUIRED_FLAGS (METHOD_ATTRIBUTE_SPECIAL_NAME | METHOD_ATTRIBUTE_RT_SPECIAL_NAME)
#define CTOR_INVALID_FLAGS (METHOD_ATTRIBUTE_STATIC)
static gboolean
mono_method_is_constructor (MonoMethod *method)
{
return ((method->flags & CTOR_REQUIRED_FLAGS) == CTOR_REQUIRED_FLAGS &&
!(method->flags & CTOR_INVALID_FLAGS) &&
!strcmp (".ctor", method->name));
}
static gboolean
mono_class_has_default_constructor (MonoClass *klass)
{
MonoMethod *method;
int i;
mono_class_setup_methods (klass);
if (klass->exception_type)
return FALSE;
for (i = 0; i < klass->method.count; ++i) {
method = klass->methods [i];
if (mono_method_is_constructor (method) &&
mono_method_signature (method) &&
mono_method_signature (method)->param_count == 0 &&
(method->flags & METHOD_ATTRIBUTE_MEMBER_ACCESS_MASK) == METHOD_ATTRIBUTE_PUBLIC)
return TRUE;
}
return FALSE;
}
/*
* Verify if @type is valid for the given @ctx verification context.
* this function checks for VAR and MVAR types that are invalid under the current verifier,
*/
static gboolean
mono_type_is_valid_type_in_context_full (MonoType *type, MonoGenericContext *context, gboolean check_gtd)
{
int i;
MonoGenericInst *inst;
switch (type->type) {
case MONO_TYPE_VAR:
case MONO_TYPE_MVAR:
if (!context)
return FALSE;
inst = type->type == MONO_TYPE_VAR ? context->class_inst : context->method_inst;
if (!inst || mono_type_get_generic_param_num (type) >= inst->type_argc)
return FALSE;
break;
case MONO_TYPE_SZARRAY:
return mono_type_is_valid_type_in_context_full (&type->data.klass->byval_arg, context, check_gtd);
case MONO_TYPE_ARRAY:
return mono_type_is_valid_type_in_context_full (&type->data.array->eklass->byval_arg, context, check_gtd);
case MONO_TYPE_PTR:
return mono_type_is_valid_type_in_context_full (type->data.type, context, check_gtd);
case MONO_TYPE_GENERICINST:
inst = type->data.generic_class->context.class_inst;
if (!inst->is_open)
break;
for (i = 0; i < inst->type_argc; ++i)
if (!mono_type_is_valid_type_in_context_full (inst->type_argv [i], context, check_gtd))
return FALSE;
break;
case MONO_TYPE_CLASS:
case MONO_TYPE_VALUETYPE: {
MonoClass *klass = type->data.klass;
/*
* It's possible to encode generic'sh types in such a way that they disguise themselves as class or valuetype.
* Fixing the type decoding is really tricky since under some cases this behavior is needed, for example, to
* have a 'class' type pointing to a 'genericinst' class.
*
* For the runtime these non canonical (weird) encodings work fine, the worst they can cause is some
* reflection oddities which are harmless - to security at least.
*/
if (klass->byval_arg.type != type->type)
return mono_type_is_valid_type_in_context_full (&klass->byval_arg, context, check_gtd);
if (check_gtd && klass->generic_container)
return FALSE;
break;
}
default:
break;
}
return TRUE;
}
static gboolean
mono_type_is_valid_type_in_context (MonoType *type, MonoGenericContext *context)
{
return mono_type_is_valid_type_in_context_full (type, context, FALSE);
}
/*This function returns NULL if the type is not instantiatable*/
static MonoType*
verifier_inflate_type (VerifyContext *ctx, MonoType *type, MonoGenericContext *context)
{
MonoError error;
MonoType *result;
result = mono_class_inflate_generic_type_checked (type, context, &error);
if (!mono_error_ok (&error)) {
mono_error_cleanup (&error);
return NULL;
}
return result;
}
/*A side note here. We don't need to check if arguments are broken since this
is only need to be done by the runtime before realizing the type.
*/
static gboolean
is_valid_generic_instantiation (MonoGenericContainer *gc, MonoGenericContext *context, MonoGenericInst *ginst)
{
MonoError error;
int i;
if (ginst->type_argc != gc->type_argc)
return FALSE;
for (i = 0; i < gc->type_argc; ++i) {
MonoGenericParamInfo *param_info = mono_generic_container_get_param_info (gc, i);
MonoClass *paramClass;
MonoClass **constraints;
MonoType *param_type = ginst->type_argv [i];
/*it's not our job to validate type variables*/
if (mono_type_is_generic_argument (param_type))
continue;
paramClass = mono_class_from_mono_type (param_type);
/* A GTD can't be a generic argument.
*
* Due to how types are encoded we must check for the case of a genericinst MonoType and GTD MonoClass.
* This happens in cases such as: class Foo<T> { void X() { new Bar<T> (); } }
*
* Open instantiations can have GTDs as this happens when one type is instantiated with others params
* and the former has an expansion into the later. For example:
* class B<K> {}
* class A<T>: B<K> {}
* The type A <K> has a parent B<K>, that is inflated into the GTD B<>.
* Since A<K> is open, thus not instantiatable, this is valid.
*/
if (paramClass->generic_container && param_type->type != MONO_TYPE_GENERICINST && !ginst->is_open)
return FALSE;
/*it's not safe to call mono_class_init from here*/
if (paramClass->generic_class && !paramClass->inited) {
if (!mono_class_is_valid_generic_instantiation (NULL, paramClass))
return FALSE;
}
if (!param_info->constraints && !(param_info->flags & GENERIC_PARAMETER_ATTRIBUTE_SPECIAL_CONSTRAINTS_MASK))
continue;
if ((param_info->flags & GENERIC_PARAMETER_ATTRIBUTE_VALUE_TYPE_CONSTRAINT) && (!paramClass->valuetype || mono_class_is_nullable (paramClass)))
return FALSE;
if ((param_info->flags & GENERIC_PARAMETER_ATTRIBUTE_REFERENCE_TYPE_CONSTRAINT) && paramClass->valuetype)
return FALSE;
if ((param_info->flags & GENERIC_PARAMETER_ATTRIBUTE_CONSTRUCTOR_CONSTRAINT) && !paramClass->valuetype && !mono_class_has_default_constructor (paramClass))
return FALSE;
if (!param_info->constraints)
continue;
for (constraints = param_info->constraints; *constraints; ++constraints) {
MonoClass *ctr = *constraints;
MonoType *inflated;
inflated = mono_class_inflate_generic_type_checked (&ctr->byval_arg, context, &error);
if (!mono_error_ok (&error)) {
mono_error_cleanup (&error);
return FALSE;
}
ctr = mono_class_from_mono_type (inflated);
mono_metadata_free_type (inflated);
/*FIXME maybe we need the same this as verifier_class_is_assignable_from*/
if (!mono_class_is_assignable_from_slow (ctr, paramClass))
return FALSE;
}
}
return TRUE;
}
/*
* Return true if @candidate is constraint compatible with @target.
*
* This means that @candidate constraints are a super set of @target constaints
*/
static gboolean
mono_generic_param_is_constraint_compatible (VerifyContext *ctx, MonoGenericParam *target, MonoGenericParam *candidate, MonoClass *candidate_param_class, MonoGenericContext *context)
{
MonoGenericParamInfo *tinfo = mono_generic_param_info (target);
MonoGenericParamInfo *cinfo = mono_generic_param_info (candidate);
MonoClass **candidate_class;
gboolean class_constraint_satisfied = FALSE;
gboolean valuetype_constraint_satisfied = FALSE;
int tmask = tinfo->flags & GENERIC_PARAMETER_ATTRIBUTE_SPECIAL_CONSTRAINTS_MASK;
int cmask = cinfo->flags & GENERIC_PARAMETER_ATTRIBUTE_SPECIAL_CONSTRAINTS_MASK;
if (cinfo->constraints) {
for (candidate_class = cinfo->constraints; *candidate_class; ++candidate_class) {
MonoClass *cc;
MonoType *inflated = verifier_inflate_type (ctx, &(*candidate_class)->byval_arg, ctx->generic_context);
if (!inflated)
return FALSE;
cc = mono_class_from_mono_type (inflated);
mono_metadata_free_type (inflated);
if (mono_type_is_reference (&cc->byval_arg) && !MONO_CLASS_IS_INTERFACE (cc))
class_constraint_satisfied = TRUE;
else if (!mono_type_is_reference (&cc->byval_arg) && !MONO_CLASS_IS_INTERFACE (cc))
valuetype_constraint_satisfied = TRUE;
}
}
class_constraint_satisfied |= (cmask & GENERIC_PARAMETER_ATTRIBUTE_REFERENCE_TYPE_CONSTRAINT) != 0;
valuetype_constraint_satisfied |= (cmask & GENERIC_PARAMETER_ATTRIBUTE_VALUE_TYPE_CONSTRAINT) != 0;
if ((tmask & GENERIC_PARAMETER_ATTRIBUTE_REFERENCE_TYPE_CONSTRAINT) && !class_constraint_satisfied)
return FALSE;
if ((tmask & GENERIC_PARAMETER_ATTRIBUTE_VALUE_TYPE_CONSTRAINT) && !valuetype_constraint_satisfied)
return FALSE;
if ((tmask & GENERIC_PARAMETER_ATTRIBUTE_CONSTRUCTOR_CONSTRAINT) && !((cmask & GENERIC_PARAMETER_ATTRIBUTE_CONSTRUCTOR_CONSTRAINT) ||
valuetype_constraint_satisfied)) {
return FALSE;
}
if (tinfo->constraints) {
MonoClass **target_class;
for (target_class = tinfo->constraints; *target_class; ++target_class) {
MonoClass *tc;
MonoType *inflated = verifier_inflate_type (ctx, &(*target_class)->byval_arg, context);
if (!inflated)
return FALSE;
tc = mono_class_from_mono_type (inflated);
mono_metadata_free_type (inflated);
/*
* A constraint from @target might inflate into @candidate itself and in that case we don't need
* check it's constraints since it satisfy the constraint by itself.
*/
if (mono_metadata_type_equal (&tc->byval_arg, &candidate_param_class->byval_arg))
continue;
if (!cinfo->constraints)
return FALSE;
for (candidate_class = cinfo->constraints; *candidate_class; ++candidate_class) {
MonoClass *cc;
inflated = verifier_inflate_type (ctx, &(*candidate_class)->byval_arg, ctx->generic_context);
if (!inflated)
return FALSE;
cc = mono_class_from_mono_type (inflated);
mono_metadata_free_type (inflated);
if (verifier_class_is_assignable_from (tc, cc))
break;
/*
* This happens when we have the following:
*
* Bar<K> where K : IFace
* Foo<T, U> where T : U where U : IFace
* ...
* Bar<T> <- T here satisfy K constraint transitively through to U's constraint
*
*/
if (mono_type_is_generic_argument (&cc->byval_arg)) {
MonoGenericParam *other_candidate = verifier_get_generic_param_from_type (ctx, &cc->byval_arg);
if (mono_generic_param_is_constraint_compatible (ctx, target, other_candidate, cc, context)) {
break;
}
}
}
if (!*candidate_class)
return FALSE;
}
}
return TRUE;
}
static MonoGenericParam*
verifier_get_generic_param_from_type (VerifyContext *ctx, MonoType *type)
{
MonoGenericContainer *gc;
MonoMethod *method = ctx->method;
int num;
num = mono_type_get_generic_param_num (type);
if (type->type == MONO_TYPE_VAR) {
MonoClass *gtd = method->klass;
if (gtd->generic_class)
gtd = gtd->generic_class->container_class;
gc = gtd->generic_container;
} else { //MVAR
MonoMethod *gmd = method;
if (method->is_inflated)
gmd = ((MonoMethodInflated*)method)->declaring;
gc = mono_method_get_generic_container (gmd);
}
if (!gc)
return NULL;
return mono_generic_container_get_param (gc, num);
}
/*
* Verify if @type is valid for the given @ctx verification context.
* this function checks for VAR and MVAR types that are invalid under the current verifier,
* This means that it either
*/
static gboolean
is_valid_type_in_context (VerifyContext *ctx, MonoType *type)
{
return mono_type_is_valid_type_in_context (type, ctx->generic_context);
}
static gboolean
is_valid_generic_instantiation_in_context (VerifyContext *ctx, MonoGenericInst *ginst, gboolean check_gtd)
{
int i;
for (i = 0; i < ginst->type_argc; ++i) {
MonoType *type = ginst->type_argv [i];
if (!mono_type_is_valid_type_in_context_full (type, ctx->generic_context, TRUE))
return FALSE;
}
return TRUE;
}
static gboolean
generic_arguments_respect_constraints (VerifyContext *ctx, MonoGenericContainer *gc, MonoGenericContext *context, MonoGenericInst *ginst)
{
int i;
for (i = 0; i < ginst->type_argc; ++i) {
MonoType *type = ginst->type_argv [i];
MonoGenericParam *target = mono_generic_container_get_param (gc, i);
MonoGenericParam *candidate;
MonoClass *candidate_class;
if (!mono_type_is_generic_argument (type))
continue;
if (!is_valid_type_in_context (ctx, type))
return FALSE;
candidate = verifier_get_generic_param_from_type (ctx, type);
candidate_class = mono_class_from_mono_type (type);
if (!mono_generic_param_is_constraint_compatible (ctx, target, candidate, candidate_class, context))
return FALSE;
}
return TRUE;
}
static gboolean
mono_method_repect_method_constraints (VerifyContext *ctx, MonoMethod *method)
{
MonoMethodInflated *gmethod = (MonoMethodInflated *)method;
MonoGenericInst *ginst = gmethod->context.method_inst;
MonoGenericContainer *gc = mono_method_get_generic_container (gmethod->declaring);
return !gc || generic_arguments_respect_constraints (ctx, gc, &gmethod->context, ginst);
}
static gboolean
mono_class_repect_method_constraints (VerifyContext *ctx, MonoClass *klass)
{
MonoGenericClass *gklass = klass->generic_class;
MonoGenericInst *ginst = gklass->context.class_inst;
MonoGenericContainer *gc = gklass->container_class->generic_container;
return !gc || generic_arguments_respect_constraints (ctx, gc, &gklass->context, ginst);
}
static gboolean
mono_method_is_valid_generic_instantiation (VerifyContext *ctx, MonoMethod *method)
{
MonoMethodInflated *gmethod = (MonoMethodInflated *)method;
MonoGenericInst *ginst = gmethod->context.method_inst;
MonoGenericContainer *gc = mono_method_get_generic_container (gmethod->declaring);
if (!gc) /*non-generic inflated method - it's part of a generic type */
return TRUE;
if (ctx && !is_valid_generic_instantiation_in_context (ctx, ginst, TRUE))
return FALSE;
return is_valid_generic_instantiation (gc, &gmethod->context, ginst);
}
static gboolean
mono_class_is_valid_generic_instantiation (VerifyContext *ctx, MonoClass *klass)
{
MonoGenericClass *gklass = klass->generic_class;
MonoGenericInst *ginst = gklass->context.class_inst;
MonoGenericContainer *gc = gklass->container_class->generic_container;
if (ctx && !is_valid_generic_instantiation_in_context (ctx, ginst, TRUE))
return FALSE;
return is_valid_generic_instantiation (gc, &gklass->context, ginst);
}
static gboolean
mono_type_is_valid_in_context (VerifyContext *ctx, MonoType *type)
{
MonoClass *klass;
if (type == NULL) {
ADD_VERIFY_ERROR2 (ctx, g_strdup_printf ("Invalid null type at 0x%04x", ctx->ip_offset), MONO_EXCEPTION_BAD_IMAGE);
return FALSE;
}
if (!is_valid_type_in_context (ctx, type)) {
char *str = mono_type_full_name (type);
ADD_VERIFY_ERROR2 (ctx, g_strdup_printf ("Invalid generic type (%s%s) (argument out of range or %s is not generic) at 0x%04x",
str [0] == '!' ? "" : type->type == MONO_TYPE_VAR ? "!" : "!!",
str,
type->type == MONO_TYPE_VAR ? "class" : "method",
ctx->ip_offset),
MONO_EXCEPTION_BAD_IMAGE);
g_free (str);
return FALSE;
}
klass = mono_class_from_mono_type (type);
mono_class_init (klass);
if (mono_loader_get_last_error () || klass->exception_type != MONO_EXCEPTION_NONE) {
if (klass->generic_class && !mono_class_is_valid_generic_instantiation (NULL, klass))
ADD_VERIFY_ERROR2 (ctx, g_strdup_printf ("Invalid generic instantiation of type %s.%s at 0x%04x", klass->name_space, klass->name, ctx->ip_offset), MONO_EXCEPTION_TYPE_LOAD);
else
ADD_VERIFY_ERROR2 (ctx, g_strdup_printf ("Could not load type %s.%s at 0x%04x", klass->name_space, klass->name, ctx->ip_offset), MONO_EXCEPTION_TYPE_LOAD);
mono_loader_clear_error ();
return FALSE;
}
if (klass->generic_class && klass->generic_class->container_class->exception_type != MONO_EXCEPTION_NONE) {
ADD_VERIFY_ERROR2 (ctx, g_strdup_printf ("Could not load type %s.%s at 0x%04x", klass->name_space, klass->name, ctx->ip_offset), MONO_EXCEPTION_TYPE_LOAD);
return FALSE;
}
if (!klass->generic_class)
return TRUE;
if (!mono_class_is_valid_generic_instantiation (ctx, klass)) {
ADD_VERIFY_ERROR2 (ctx, g_strdup_printf ("Invalid generic type instantiation of type %s.%s at 0x%04x", klass->name_space, klass->name, ctx->ip_offset), MONO_EXCEPTION_TYPE_LOAD);
return FALSE;
}
if (!mono_class_repect_method_constraints (ctx, klass)) {
ADD_VERIFY_ERROR2 (ctx, g_strdup_printf ("Invalid generic type instantiation of type %s.%s (generic args don't respect target's constraints) at 0x%04x", klass->name_space, klass->name, ctx->ip_offset), MONO_EXCEPTION_TYPE_LOAD);
return FALSE;
}
return TRUE;
}
static verify_result_t
mono_method_is_valid_in_context (VerifyContext *ctx, MonoMethod *method)
{
if (!mono_type_is_valid_in_context (ctx, &method->klass->byval_arg))
return RESULT_INVALID;
if (!method->is_inflated)
return RESULT_VALID;
if (!mono_method_is_valid_generic_instantiation (ctx, method)) {
ADD_VERIFY_ERROR2 (ctx, g_strdup_printf ("Invalid generic method instantiation of method %s.%s::%s at 0x%04x", method->klass->name_space, method->klass->name, method->name, ctx->ip_offset), MONO_EXCEPTION_UNVERIFIABLE_IL);
return RESULT_INVALID;
}
if (!mono_method_repect_method_constraints (ctx, method)) {
CODE_NOT_VERIFIABLE (ctx, g_strdup_printf ("Invalid generic method instantiation of method %s.%s::%s (generic args don't respect target's constraints) at 0x%04x", method->klass->name_space, method->klass->name, method->name, ctx->ip_offset));
return RESULT_UNVERIFIABLE;
}
return RESULT_VALID;
}
static MonoClassField*
verifier_load_field (VerifyContext *ctx, int token, MonoClass **out_klass, const char *opcode) {
MonoError error;
MonoClassField *field;
MonoClass *klass = NULL;
if (ctx->method->wrapper_type != MONO_WRAPPER_NONE) {
field = (MonoClassField *)mono_method_get_wrapper_data (ctx->method, (guint32)token);
klass = field ? field->parent : NULL;
} else {
if (!IS_FIELD_DEF_OR_REF (token) || !token_bounds_check (ctx->image, token)) {
ADD_VERIFY_ERROR2 (ctx, g_strdup_printf ("Invalid field token 0x%08x for %s at 0x%04x", token, opcode, ctx->ip_offset), MONO_EXCEPTION_BAD_IMAGE);
return NULL;
}
field = mono_field_from_token_checked (ctx->image, token, &klass, ctx->generic_context, &error);
mono_error_cleanup (&error); /*FIXME don't swallow the error */
}
if (!field || !field->parent || !klass) {
ADD_VERIFY_ERROR2 (ctx, g_strdup_printf ("Cannot load field from token 0x%08x for %s at 0x%04x", token, opcode, ctx->ip_offset), MONO_EXCEPTION_BAD_IMAGE);
return NULL;
}
if (!mono_type_is_valid_in_context (ctx, &klass->byval_arg))
return NULL;
if (mono_field_get_flags (field) & FIELD_ATTRIBUTE_LITERAL) {
char *type_name = mono_type_get_full_name (field->parent);
ADD_VERIFY_ERROR (ctx, g_strdup_printf ("Cannot reference literal field %s::%s at 0x%04x", type_name, field->name, ctx->ip_offset));
g_free (type_name);
return NULL;
}
*out_klass = klass;
return field;
}
static MonoMethod*
verifier_load_method (VerifyContext *ctx, int token, const char *opcode) {
MonoMethod* method;
if (ctx->method->wrapper_type != MONO_WRAPPER_NONE) {
method = (MonoMethod *)mono_method_get_wrapper_data (ctx->method, (guint32)token);
} else {
MonoError error;
if (!IS_METHOD_DEF_OR_REF_OR_SPEC (token) || !token_bounds_check (ctx->image, token)) {
ADD_VERIFY_ERROR2 (ctx, g_strdup_printf ("Invalid method token 0x%08x for %s at 0x%04x", token, opcode, ctx->ip_offset), MONO_EXCEPTION_BAD_IMAGE);
return NULL;
}
method = mono_get_method_checked (ctx->image, token, NULL, ctx->generic_context, &error);
mono_error_cleanup (&error); /* FIXME don't swallow this error */
}
if (!method) {
ADD_VERIFY_ERROR2 (ctx, g_strdup_printf ("Cannot load method from token 0x%08x for %s at 0x%04x", token, opcode, ctx->ip_offset), MONO_EXCEPTION_BAD_IMAGE);
return NULL;
}
if (mono_method_is_valid_in_context (ctx, method) == RESULT_INVALID)
return NULL;