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      1 /*
      2  * Copyright (C) 2008 The Android Open Source Project
      3  *
      4  * Licensed under the Apache License, Version 2.0 (the "License");
      5  * you may not use this file except in compliance with the License.
      6  * You may obtain a copy of the License at
      7  *
      8  *      http://www.apache.org/licenses/LICENSE-2.0
      9  *
     10  * Unless required by applicable law or agreed to in writing, software
     11  * distributed under the License is distributed on an "AS IS" BASIS,
     12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
     13  * See the License for the specific language governing permissions and
     14  * limitations under the License.
     15  */
     16 /*
     17  * Access .dex (Dalvik Executable Format) files.  The code here assumes that
     18  * the DEX file has been rewritten (byte-swapped, word-aligned) and that
     19  * the contents can be directly accessed as a collection of C arrays.  Please
     20  * see docs/dalvik/dex-format.html for a detailed description.
     21  *
     22  * The structure and field names were chosen to match those in the DEX spec.
     23  *
     24  * It's generally assumed that the DEX file will be stored in shared memory,
     25  * obviating the need to copy code and constant pool entries into newly
     26  * allocated storage.  Maintaining local pointers to items in the shared area
     27  * is valid and encouraged.
     28  *
     29  * All memory-mapped structures are 32-bit aligned unless otherwise noted.
     30  */
     31 #ifndef _LIBDEX_DEXFILE
     32 #define _LIBDEX_DEXFILE
     33 
     34 #include "vm/Common.h"      // basic type defs, e.g. u1/u2/u4/u8, and LOG
     35 #include "libdex/SysUtil.h"
     36 
     37 /*
     38  * gcc-style inline management -- ensures we have a copy of all functions
     39  * in the library, so code that links against us will work whether or not
     40  * it was built with optimizations enabled.
     41  */
     42 #ifndef _DEX_GEN_INLINES             /* only defined by DexInlines.c */
     43 # define DEX_INLINE extern __inline__
     44 #else
     45 # define DEX_INLINE
     46 #endif
     47 
     48 /* DEX file magic number */
     49 #define DEX_MAGIC       "dex\n"
     50 /* version, encoded in 4 bytes of ASCII */
     51 #define DEX_MAGIC_VERS  "035\0"
     52 
     53 /* same, but for optimized DEX header */
     54 #define DEX_OPT_MAGIC   "dey\n"
     55 #define DEX_OPT_MAGIC_VERS  "036\0"
     56 
     57 #define DEX_DEP_MAGIC   "deps"
     58 
     59 /*
     60  * 160-bit SHA-1 digest.
     61  */
     62 enum { kSHA1DigestLen = 20,
     63        kSHA1DigestOutputLen = kSHA1DigestLen*2 +1 };
     64 
     65 /* general constants */
     66 enum {
     67     kDexEndianConstant = 0x12345678,    /* the endianness indicator */
     68     kDexNoIndex = 0xffffffff,           /* not a valid index value */
     69 };
     70 
     71 /*
     72  * access flags and masks; the "standard" ones are all <= 0x4000
     73  *
     74  * Note: There are related declarations in vm/oo/Object.h in the ClassFlags
     75  * enum.
     76  */
     77 enum {
     78     ACC_PUBLIC       = 0x00000001,       // class, field, method, ic
     79     ACC_PRIVATE      = 0x00000002,       // field, method, ic
     80     ACC_PROTECTED    = 0x00000004,       // field, method, ic
     81     ACC_STATIC       = 0x00000008,       // field, method, ic
     82     ACC_FINAL        = 0x00000010,       // class, field, method, ic
     83     ACC_SYNCHRONIZED = 0x00000020,       // method (only allowed on natives)
     84     ACC_SUPER        = 0x00000020,       // class (not used in Dalvik)
     85     ACC_VOLATILE     = 0x00000040,       // field
     86     ACC_BRIDGE       = 0x00000040,       // method (1.5)
     87     ACC_TRANSIENT    = 0x00000080,       // field
     88     ACC_VARARGS      = 0x00000080,       // method (1.5)
     89     ACC_NATIVE       = 0x00000100,       // method
     90     ACC_INTERFACE    = 0x00000200,       // class, ic
     91     ACC_ABSTRACT     = 0x00000400,       // class, method, ic
     92     ACC_STRICT       = 0x00000800,       // method
     93     ACC_SYNTHETIC    = 0x00001000,       // field, method, ic
     94     ACC_ANNOTATION   = 0x00002000,       // class, ic (1.5)
     95     ACC_ENUM         = 0x00004000,       // class, field, ic (1.5)
     96     ACC_CONSTRUCTOR  = 0x00010000,       // method (Dalvik only)
     97     ACC_DECLARED_SYNCHRONIZED =
     98                        0x00020000,       // method (Dalvik only)
     99     ACC_CLASS_MASK =
    100         (ACC_PUBLIC | ACC_FINAL | ACC_INTERFACE | ACC_ABSTRACT
    101                 | ACC_SYNTHETIC | ACC_ANNOTATION | ACC_ENUM),
    102     ACC_INNER_CLASS_MASK =
    103         (ACC_CLASS_MASK | ACC_PRIVATE | ACC_PROTECTED | ACC_STATIC),
    104     ACC_FIELD_MASK =
    105         (ACC_PUBLIC | ACC_PRIVATE | ACC_PROTECTED | ACC_STATIC | ACC_FINAL
    106                 | ACC_VOLATILE | ACC_TRANSIENT | ACC_SYNTHETIC | ACC_ENUM),
    107     ACC_METHOD_MASK =
    108         (ACC_PUBLIC | ACC_PRIVATE | ACC_PROTECTED | ACC_STATIC | ACC_FINAL
    109                 | ACC_SYNCHRONIZED | ACC_BRIDGE | ACC_VARARGS | ACC_NATIVE
    110                 | ACC_ABSTRACT | ACC_STRICT | ACC_SYNTHETIC | ACC_CONSTRUCTOR
    111                 | ACC_DECLARED_SYNCHRONIZED),
    112 };
    113 
    114 /* annotation constants */
    115 enum {
    116     kDexVisibilityBuild         = 0x00,     /* annotation visibility */
    117     kDexVisibilityRuntime       = 0x01,
    118     kDexVisibilitySystem        = 0x02,
    119 
    120     kDexAnnotationByte          = 0x00,
    121     kDexAnnotationShort         = 0x02,
    122     kDexAnnotationChar          = 0x03,
    123     kDexAnnotationInt           = 0x04,
    124     kDexAnnotationLong          = 0x06,
    125     kDexAnnotationFloat         = 0x10,
    126     kDexAnnotationDouble        = 0x11,
    127     kDexAnnotationString        = 0x17,
    128     kDexAnnotationType          = 0x18,
    129     kDexAnnotationField         = 0x19,
    130     kDexAnnotationMethod        = 0x1a,
    131     kDexAnnotationEnum          = 0x1b,
    132     kDexAnnotationArray         = 0x1c,
    133     kDexAnnotationAnnotation    = 0x1d,
    134     kDexAnnotationNull          = 0x1e,
    135     kDexAnnotationBoolean       = 0x1f,
    136 
    137     kDexAnnotationValueTypeMask = 0x1f,     /* low 5 bits */
    138     kDexAnnotationValueArgShift = 5,
    139 };
    140 
    141 /* map item type codes */
    142 enum {
    143     kDexTypeHeaderItem               = 0x0000,
    144     kDexTypeStringIdItem             = 0x0001,
    145     kDexTypeTypeIdItem               = 0x0002,
    146     kDexTypeProtoIdItem              = 0x0003,
    147     kDexTypeFieldIdItem              = 0x0004,
    148     kDexTypeMethodIdItem             = 0x0005,
    149     kDexTypeClassDefItem             = 0x0006,
    150     kDexTypeMapList                  = 0x1000,
    151     kDexTypeTypeList                 = 0x1001,
    152     kDexTypeAnnotationSetRefList     = 0x1002,
    153     kDexTypeAnnotationSetItem        = 0x1003,
    154     kDexTypeClassDataItem            = 0x2000,
    155     kDexTypeCodeItem                 = 0x2001,
    156     kDexTypeStringDataItem           = 0x2002,
    157     kDexTypeDebugInfoItem            = 0x2003,
    158     kDexTypeAnnotationItem           = 0x2004,
    159     kDexTypeEncodedArrayItem         = 0x2005,
    160     kDexTypeAnnotationsDirectoryItem = 0x2006,
    161 };
    162 
    163 /* auxillary data section chunk codes */
    164 enum {
    165     kDexChunkClassLookup            = 0x434c4b50,   /* CLKP */
    166     kDexChunkRegisterMaps           = 0x524d4150,   /* RMAP */
    167 
    168     kDexChunkReducingIndexMap       = 0x5249584d,   /* RIXM */
    169     kDexChunkExpandingIndexMap      = 0x4549584d,   /* EIXM */
    170 
    171     kDexChunkEnd                    = 0x41454e44,   /* AEND */
    172 };
    173 
    174 /* debug info opcodes and constants */
    175 enum {
    176     DBG_END_SEQUENCE         = 0x00,
    177     DBG_ADVANCE_PC           = 0x01,
    178     DBG_ADVANCE_LINE         = 0x02,
    179     DBG_START_LOCAL          = 0x03,
    180     DBG_START_LOCAL_EXTENDED = 0x04,
    181     DBG_END_LOCAL            = 0x05,
    182     DBG_RESTART_LOCAL        = 0x06,
    183     DBG_SET_PROLOGUE_END     = 0x07,
    184     DBG_SET_EPILOGUE_BEGIN   = 0x08,
    185     DBG_SET_FILE             = 0x09,
    186     DBG_FIRST_SPECIAL        = 0x0a,
    187     DBG_LINE_BASE            = -4,
    188     DBG_LINE_RANGE           = 15,
    189 };
    190 
    191 /*
    192  * Direct-mapped "header_item" struct.
    193  */
    194 typedef struct DexHeader {
    195     u1  magic[8];           /* includes version number */
    196     u4  checksum;           /* adler32 checksum */
    197     u1  signature[kSHA1DigestLen]; /* SHA-1 hash */
    198     u4  fileSize;           /* length of entire file */
    199     u4  headerSize;         /* offset to start of next section */
    200     u4  endianTag;
    201     u4  linkSize;
    202     u4  linkOff;
    203     u4  mapOff;
    204     u4  stringIdsSize;
    205     u4  stringIdsOff;
    206     u4  typeIdsSize;
    207     u4  typeIdsOff;
    208     u4  protoIdsSize;
    209     u4  protoIdsOff;
    210     u4  fieldIdsSize;
    211     u4  fieldIdsOff;
    212     u4  methodIdsSize;
    213     u4  methodIdsOff;
    214     u4  classDefsSize;
    215     u4  classDefsOff;
    216     u4  dataSize;
    217     u4  dataOff;
    218 } DexHeader;
    219 
    220 /*
    221  * Direct-mapped "map_item".
    222  */
    223 typedef struct DexMapItem {
    224     u2  type;              /* type code (see kDexType* above) */
    225     u2  unused;
    226     u4  size;              /* count of items of the indicated type */
    227     u4  offset;            /* file offset to the start of data */
    228 } DexMapItem;
    229 
    230 /*
    231  * Direct-mapped "map_list".
    232  */
    233 typedef struct DexMapList {
    234     u4  size;               /* #of entries in list */
    235     DexMapItem list[1];     /* entries */
    236 } DexMapList;
    237 
    238 /*
    239  * Direct-mapped "string_id_item".
    240  */
    241 typedef struct DexStringId {
    242     u4  stringDataOff;      /* file offset to string_data_item */
    243 } DexStringId;
    244 
    245 /*
    246  * Direct-mapped "type_id_item".
    247  */
    248 typedef struct DexTypeId {
    249     u4  descriptorIdx;      /* index into stringIds list for type descriptor */
    250 } DexTypeId;
    251 
    252 /*
    253  * Direct-mapped "field_id_item".
    254  */
    255 typedef struct DexFieldId {
    256     u2  classIdx;           /* index into typeIds list for defining class */
    257     u2  typeIdx;            /* index into typeIds for field type */
    258     u4  nameIdx;            /* index into stringIds for field name */
    259 } DexFieldId;
    260 
    261 /*
    262  * Direct-mapped "method_id_item".
    263  */
    264 typedef struct DexMethodId {
    265     u2  classIdx;           /* index into typeIds list for defining class */
    266     u2  protoIdx;           /* index into protoIds for method prototype */
    267     u4  nameIdx;            /* index into stringIds for method name */
    268 } DexMethodId;
    269 
    270 /*
    271  * Direct-mapped "proto_id_item".
    272  */
    273 typedef struct DexProtoId {
    274     u4  shortyIdx;          /* index into stringIds for shorty descriptor */
    275     u4  returnTypeIdx;      /* index into typeIds list for return type */
    276     u4  parametersOff;      /* file offset to type_list for parameter types */
    277 } DexProtoId;
    278 
    279 /*
    280  * Direct-mapped "class_def_item".
    281  */
    282 typedef struct DexClassDef {
    283     u4  classIdx;           /* index into typeIds for this class */
    284     u4  accessFlags;
    285     u4  superclassIdx;      /* index into typeIds for superclass */
    286     u4  interfacesOff;      /* file offset to DexTypeList */
    287     u4  sourceFileIdx;      /* index into stringIds for source file name */
    288     u4  annotationsOff;     /* file offset to annotations_directory_item */
    289     u4  classDataOff;       /* file offset to class_data_item */
    290     u4  staticValuesOff;    /* file offset to DexEncodedArray */
    291 } DexClassDef;
    292 
    293 /*
    294  * Direct-mapped "type_item".
    295  */
    296 typedef struct DexTypeItem {
    297     u2  typeIdx;            /* index into typeIds */
    298 } DexTypeItem;
    299 
    300 /*
    301  * Direct-mapped "type_list".
    302  */
    303 typedef struct DexTypeList {
    304     u4  size;               /* #of entries in list */
    305     DexTypeItem list[1];    /* entries */
    306 } DexTypeList;
    307 
    308 /*
    309  * Direct-mapped "code_item".
    310  *
    311  * The "catches" table is used when throwing an exception,
    312  * "debugInfo" is used when displaying an exception stack trace or
    313  * debugging. An offset of zero indicates that there are no entries.
    314  */
    315 typedef struct DexCode {
    316     u2  registersSize;
    317     u2  insSize;
    318     u2  outsSize;
    319     u2  triesSize;
    320     u4  debugInfoOff;       /* file offset to debug info stream */
    321     u4  insnsSize;          /* size of the insns array, in u2 units */
    322     u2  insns[1];
    323     /* followed by optional u2 padding */
    324     /* followed by try_item[triesSize] */
    325     /* followed by uleb128 handlersSize */
    326     /* followed by catch_handler_item[handlersSize] */
    327 } DexCode;
    328 
    329 /*
    330  * Direct-mapped "try_item".
    331  */
    332 typedef struct DexTry {
    333     u4  startAddr;          /* start address, in 16-bit code units */
    334     u2  insnCount;          /* instruction count, in 16-bit code units */
    335     u2  handlerOff;         /* offset in encoded handler data to handlers */
    336 } DexTry;
    337 
    338 /*
    339  * Link table.  Currently undefined.
    340  */
    341 typedef struct DexLink {
    342     u1  bleargh;
    343 } DexLink;
    344 
    345 
    346 /*
    347  * Direct-mapped "annotations_directory_item".
    348  */
    349 typedef struct DexAnnotationsDirectoryItem {
    350     u4  classAnnotationsOff;  /* offset to DexAnnotationSetItem */
    351     u4  fieldsSize;           /* count of DexFieldAnnotationsItem */
    352     u4  methodsSize;          /* count of DexMethodAnnotationsItem */
    353     u4  parametersSize;       /* count of DexParameterAnnotationsItem */
    354     /* followed by DexFieldAnnotationsItem[fieldsSize] */
    355     /* followed by DexMethodAnnotationsItem[methodsSize] */
    356     /* followed by DexParameterAnnotationsItem[parametersSize] */
    357 } DexAnnotationsDirectoryItem;
    358 
    359 /*
    360  * Direct-mapped "field_annotations_item".
    361  */
    362 typedef struct DexFieldAnnotationsItem {
    363     u4  fieldIdx;
    364     u4  annotationsOff;             /* offset to DexAnnotationSetItem */
    365 } DexFieldAnnotationsItem;
    366 
    367 /*
    368  * Direct-mapped "method_annotations_item".
    369  */
    370 typedef struct DexMethodAnnotationsItem {
    371     u4  methodIdx;
    372     u4  annotationsOff;             /* offset to DexAnnotationSetItem */
    373 } DexMethodAnnotationsItem;
    374 
    375 /*
    376  * Direct-mapped "parameter_annotations_item".
    377  */
    378 typedef struct DexParameterAnnotationsItem {
    379     u4  methodIdx;
    380     u4  annotationsOff;             /* offset to DexAnotationSetRefList */
    381 } DexParameterAnnotationsItem;
    382 
    383 /*
    384  * Direct-mapped "annotation_set_ref_item".
    385  */
    386 typedef struct DexAnnotationSetRefItem {
    387     u4  annotationsOff;             /* offset to DexAnnotationSetItem */
    388 } DexAnnotationSetRefItem;
    389 
    390 /*
    391  * Direct-mapped "annotation_set_ref_list".
    392  */
    393 typedef struct DexAnnotationSetRefList {
    394     u4  size;
    395     DexAnnotationSetRefItem list[1];
    396 } DexAnnotationSetRefList;
    397 
    398 /*
    399  * Direct-mapped "anotation_set_item".
    400  */
    401 typedef struct DexAnnotationSetItem {
    402     u4  size;
    403     u4  entries[1];                 /* offset to DexAnnotationItem */
    404 } DexAnnotationSetItem;
    405 
    406 /*
    407  * Direct-mapped "annotation_item".
    408  *
    409  * NOTE: this structure is byte-aligned.
    410  */
    411 typedef struct DexAnnotationItem {
    412     u1  visibility;
    413     u1  annotation[1];              /* data in encoded_annotation format */
    414 } DexAnnotationItem;
    415 
    416 /*
    417  * Direct-mapped "encoded_array".
    418  *
    419  * NOTE: this structure is byte-aligned.
    420  */
    421 typedef struct DexEncodedArray {
    422     u1  array[1];                   /* data in encoded_array format */
    423 } DexEncodedArray;
    424 
    425 /*
    426  * Lookup table for classes.  It provides a mapping from class name to
    427  * class definition.  Used by dexFindClass().
    428  *
    429  * We calculate this at DEX optimization time and embed it in the file so we
    430  * don't need the same hash table in every VM.  This is slightly slower than
    431  * a hash table with direct pointers to the items, but because it's shared
    432  * there's less of a penalty for using a fairly sparse table.
    433  */
    434 typedef struct DexClassLookup {
    435     int     size;                       // total size, including "size"
    436     int     numEntries;                 // size of table[]; always power of 2
    437     struct {
    438         u4      classDescriptorHash;    // class descriptor hash code
    439         int     classDescriptorOffset;  // in bytes, from start of DEX
    440         int     classDefOffset;         // in bytes, from start of DEX
    441     } table[1];
    442 } DexClassLookup;
    443 
    444 /*
    445  * Map constant pool indices from one form to another.  Some or all of these
    446  * may be NULL.
    447  *
    448  * The map values are 16-bit unsigned values.  If the values we map to
    449  * require a larger range, we omit the mapping for that category (which
    450  * requires that the lookup code recognize that the data will not be
    451  * there for all DEX files in all categories.)
    452  */
    453 typedef struct DexIndexMap {
    454     const u2* classMap;         /* map, either expanding or reducing */
    455     u4  classFullCount;         /* same as typeIdsSize */
    456     u4  classReducedCount;      /* post-reduction count */
    457     const u2* methodMap;
    458     u4  methodFullCount;
    459     u4  methodReducedCount;
    460     const u2* fieldMap;
    461     u4  fieldFullCount;
    462     u4  fieldReducedCount;
    463     const u2* stringMap;
    464     u4  stringFullCount;
    465     u4  stringReducedCount;
    466 } DexIndexMap;
    467 
    468 /*
    469  * Header added by DEX optimization pass.  Values are always written in
    470  * local byte and structure padding.  The first field (magic + version)
    471  * is guaranteed to be present and directly readable for all expected
    472  * compiler configurations; the rest is version-dependent.
    473  *
    474  * Try to keep this simple and fixed-size.
    475  */
    476 typedef struct DexOptHeader {
    477     u1  magic[8];           /* includes version number */
    478 
    479     u4  dexOffset;          /* file offset of DEX header */
    480     u4  dexLength;
    481     u4  depsOffset;         /* offset of optimized DEX dependency table */
    482     u4  depsLength;
    483     u4  auxOffset;          /* file offset of pre-calc auxillary data */
    484     u4  auxLength;
    485 
    486     u4  flags;              /* some info flags */
    487     u4  checksum;           /* adler32 checksum covering deps/aux */
    488 
    489     /* pad for 64-bit alignment if necessary */
    490 } DexOptHeader;
    491 
    492 #define DEX_FLAG_VERIFIED           (1)     /* tried to verify all classes */
    493 #define DEX_OPT_FLAG_BIG            (1<<1)  /* swapped to big-endian */
    494 #define DEX_OPT_FLAG_FIELDS         (1<<2)  /* field access optimized */
    495 #define DEX_OPT_FLAG_INVOCATIONS    (1<<3)  /* method calls optimized */
    496 
    497 #define DEX_INTERFACE_CACHE_SIZE    128     /* must be power of 2 */
    498 
    499 /*
    500  * Structure representing a DEX file.
    501  *
    502  * Code should regard DexFile as opaque, using the API calls provided here
    503  * to access specific structures.
    504  */
    505 typedef struct DexFile {
    506     /* directly-mapped "opt" header */
    507     const DexOptHeader* pOptHeader;
    508 
    509     /* pointers to directly-mapped structs and arrays in base DEX */
    510     const DexHeader*    pHeader;
    511     const DexStringId*  pStringIds;
    512     const DexTypeId*    pTypeIds;
    513     const DexFieldId*   pFieldIds;
    514     const DexMethodId*  pMethodIds;
    515     const DexProtoId*   pProtoIds;
    516     const DexClassDef*  pClassDefs;
    517     const DexLink*      pLinkData;
    518 
    519     /*
    520      * These are mapped out of the "auxillary" section, and may not be
    521      * included in the file.
    522      */
    523     const DexClassLookup* pClassLookup;
    524     DexIndexMap         indexMap;
    525     const void*         pRegisterMapPool;       // RegisterMapClassPool
    526 
    527     /* points to start of DEX file data */
    528     const u1*           baseAddr;
    529 
    530     /* track memory overhead for auxillary structures */
    531     int                 overhead;
    532 
    533     /* additional app-specific data structures associated with the DEX */
    534     //void*               auxData;
    535 } DexFile;
    536 
    537 /*
    538  * Utility function -- rounds up to the nearest power of 2.
    539  */
    540 u4 dexRoundUpPower2(u4 val);
    541 
    542 /*
    543  * Parse an optimized or unoptimized .dex file sitting in memory.
    544  *
    545  * On success, return a newly-allocated DexFile.
    546  */
    547 DexFile* dexFileParse(const u1* data, size_t length, int flags);
    548 
    549 /* bit values for "flags" argument to dexFileParse */
    550 enum {
    551     kDexParseDefault            = 0,
    552     kDexParseVerifyChecksum     = 1,
    553     kDexParseContinueOnError    = (1 << 1),
    554 };
    555 
    556 /*
    557  * Correct the byte ordering in a memory-mapped DEX file.  This is only
    558  * required for code that opens "raw" DEX files, such as the DEX optimizer.
    559  *
    560  * Return 0 on success.
    561  */
    562 int dexFixByteOrdering(u1* addr, int len);
    563 
    564 /*
    565  * Compute DEX checksum.
    566  */
    567 u4 dexComputeChecksum(const DexHeader* pHeader);
    568 
    569 /*
    570  * Free a DexFile structure, along with any associated structures.
    571  */
    572 void dexFileFree(DexFile* pDexFile);
    573 
    574 /*
    575  * Create class lookup table.
    576  */
    577 DexClassLookup* dexCreateClassLookup(DexFile* pDexFile);
    578 
    579 /*
    580  * Find a class definition by descriptor.
    581  */
    582 const DexClassDef* dexFindClass(const DexFile* pFile, const char* descriptor);
    583 
    584 /*
    585  * Set up the basic raw data pointers of a DexFile. This function isn't
    586  * meant for general use.
    587  */
    588 void dexFileSetupBasicPointers(DexFile* pDexFile, const u1* data);
    589 
    590 /* return the DexMapList of the file, if any */
    591 DEX_INLINE const DexMapList* dexGetMap(const DexFile* pDexFile) {
    592     u4 mapOff = pDexFile->pHeader->mapOff;
    593 
    594     if (mapOff == 0) {
    595         return NULL;
    596     } else {
    597         return (const DexMapList*) (pDexFile->baseAddr + mapOff);
    598     }
    599 }
    600 
    601 /* return the const char* string data referred to by the given string_id */
    602 DEX_INLINE const char* dexGetStringData(const DexFile* pDexFile,
    603         const DexStringId* pStringId) {
    604     const u1* ptr = pDexFile->baseAddr + pStringId->stringDataOff;
    605 
    606     // Skip the uleb128 length.
    607     while (*(ptr++) > 0x7f) /* empty */ ;
    608 
    609     return (const char*) ptr;
    610 }
    611 /* return the StringId with the specified index */
    612 DEX_INLINE const DexStringId* dexGetStringId(const DexFile* pDexFile, u4 idx) {
    613     assert(idx < pDexFile->pHeader->stringIdsSize);
    614     return &pDexFile->pStringIds[idx];
    615 }
    616 /* return the UTF-8 encoded string with the specified string_id index */
    617 DEX_INLINE const char* dexStringById(const DexFile* pDexFile, u4 idx) {
    618     const DexStringId* pStringId = dexGetStringId(pDexFile, idx);
    619     return dexGetStringData(pDexFile, pStringId);
    620 }
    621 
    622 /* Return the UTF-8 encoded string with the specified string_id index,
    623  * also filling in the UTF-16 size (number of 16-bit code points).*/
    624 const char* dexStringAndSizeById(const DexFile* pDexFile, u4 idx,
    625         u4* utf16Size);
    626 
    627 /* return the TypeId with the specified index */
    628 DEX_INLINE const DexTypeId* dexGetTypeId(const DexFile* pDexFile, u4 idx) {
    629     assert(idx < pDexFile->pHeader->typeIdsSize);
    630     return &pDexFile->pTypeIds[idx];
    631 }
    632 
    633 /*
    634  * Get the descriptor string associated with a given type index.
    635  * The caller should not free() the returned string.
    636  */
    637 DEX_INLINE const char* dexStringByTypeIdx(const DexFile* pDexFile, u4 idx) {
    638     const DexTypeId* typeId = dexGetTypeId(pDexFile, idx);
    639     return dexStringById(pDexFile, typeId->descriptorIdx);
    640 }
    641 
    642 /* return the MethodId with the specified index */
    643 DEX_INLINE const DexMethodId* dexGetMethodId(const DexFile* pDexFile, u4 idx) {
    644     assert(idx < pDexFile->pHeader->methodIdsSize);
    645     return &pDexFile->pMethodIds[idx];
    646 }
    647 
    648 /* return the FieldId with the specified index */
    649 DEX_INLINE const DexFieldId* dexGetFieldId(const DexFile* pDexFile, u4 idx) {
    650     assert(idx < pDexFile->pHeader->fieldIdsSize);
    651     return &pDexFile->pFieldIds[idx];
    652 }
    653 
    654 /* return the ProtoId with the specified index */
    655 DEX_INLINE const DexProtoId* dexGetProtoId(const DexFile* pDexFile, u4 idx) {
    656     assert(idx < pDexFile->pHeader->protoIdsSize);
    657     return &pDexFile->pProtoIds[idx];
    658 }
    659 
    660 /*
    661  * Get the parameter list from a ProtoId. The returns NULL if the ProtoId
    662  * does not have a parameter list.
    663  */
    664 DEX_INLINE const DexTypeList* dexGetProtoParameters(
    665     const DexFile *pDexFile, const DexProtoId* pProtoId) {
    666     if (pProtoId->parametersOff == 0) {
    667         return NULL;
    668     }
    669     return (const DexTypeList*)
    670         (pDexFile->baseAddr + pProtoId->parametersOff);
    671 }
    672 
    673 /* return the ClassDef with the specified index */
    674 DEX_INLINE const DexClassDef* dexGetClassDef(const DexFile* pDexFile, u4 idx) {
    675     assert(idx < pDexFile->pHeader->classDefsSize);
    676     return &pDexFile->pClassDefs[idx];
    677 }
    678 
    679 /* given a ClassDef pointer, recover its index */
    680 DEX_INLINE u4 dexGetIndexForClassDef(const DexFile* pDexFile,
    681     const DexClassDef* pClassDef)
    682 {
    683     assert(pClassDef >= pDexFile->pClassDefs &&
    684            pClassDef < pDexFile->pClassDefs + pDexFile->pHeader->classDefsSize);
    685     return pClassDef - pDexFile->pClassDefs;
    686 }
    687 
    688 /* get the interface list for a DexClass */
    689 DEX_INLINE const DexTypeList* dexGetInterfacesList(const DexFile* pDexFile,
    690     const DexClassDef* pClassDef)
    691 {
    692     if (pClassDef->interfacesOff == 0)
    693         return NULL;
    694     return (const DexTypeList*)
    695         (pDexFile->baseAddr + pClassDef->interfacesOff);
    696 }
    697 /* return the Nth entry in a DexTypeList. */
    698 DEX_INLINE const DexTypeItem* dexGetTypeItem(const DexTypeList* pList,
    699     u4 idx)
    700 {
    701     assert(idx < pList->size);
    702     return &pList->list[idx];
    703 }
    704 /* return the type_idx for the Nth entry in a TypeList */
    705 DEX_INLINE u4 dexTypeListGetIdx(const DexTypeList* pList, u4 idx) {
    706     const DexTypeItem* pItem = dexGetTypeItem(pList, idx);
    707     return pItem->typeIdx;
    708 }
    709 
    710 /* get the static values list for a DexClass */
    711 DEX_INLINE const DexEncodedArray* dexGetStaticValuesList(
    712     const DexFile* pDexFile, const DexClassDef* pClassDef)
    713 {
    714     if (pClassDef->staticValuesOff == 0)
    715         return NULL;
    716     return (const DexEncodedArray*)
    717         (pDexFile->baseAddr + pClassDef->staticValuesOff);
    718 }
    719 
    720 /* get the annotations directory item for a DexClass */
    721 DEX_INLINE const DexAnnotationsDirectoryItem* dexGetAnnotationsDirectoryItem(
    722     const DexFile* pDexFile, const DexClassDef* pClassDef)
    723 {
    724     if (pClassDef->annotationsOff == 0)
    725         return NULL;
    726     return (const DexAnnotationsDirectoryItem*)
    727         (pDexFile->baseAddr + pClassDef->annotationsOff);
    728 }
    729 
    730 /* get the source file string */
    731 DEX_INLINE const char* dexGetSourceFile(
    732     const DexFile* pDexFile, const DexClassDef* pClassDef)
    733 {
    734     if (pClassDef->sourceFileIdx == 0xffffffff)
    735         return NULL;
    736     return dexStringById(pDexFile, pClassDef->sourceFileIdx);
    737 }
    738 
    739 /* get the size, in bytes, of a DexCode */
    740 size_t dexGetDexCodeSize(const DexCode* pCode);
    741 
    742 /* Get the list of "tries" for the given DexCode. */
    743 DEX_INLINE const DexTry* dexGetTries(const DexCode* pCode) {
    744     const u2* insnsEnd = &pCode->insns[pCode->insnsSize];
    745 
    746     // Round to four bytes.
    747     if ((((u4) insnsEnd) & 3) != 0) {
    748         insnsEnd++;
    749     }
    750 
    751     return (const DexTry*) insnsEnd;
    752 }
    753 
    754 /* Get the base of the encoded data for the given DexCode. */
    755 DEX_INLINE const u1* dexGetCatchHandlerData(const DexCode* pCode) {
    756     const DexTry* pTries = dexGetTries(pCode);
    757     return (const u1*) &pTries[pCode->triesSize];
    758 }
    759 
    760 /* get a pointer to the start of the debugging data */
    761 DEX_INLINE const u1* dexGetDebugInfoStream(const DexFile* pDexFile,
    762     const DexCode* pCode)
    763 {
    764     if (pCode->debugInfoOff == 0) {
    765         return NULL;
    766     } else {
    767         return pDexFile->baseAddr + pCode->debugInfoOff;
    768     }
    769 }
    770 
    771 /*
    772  * Callback for "new position table entry".
    773  * Returning non-0 causes the decoder to stop early.
    774  */
    775 typedef int (*DexDebugNewPositionCb)(void *cnxt, u4 address, u4 lineNum);
    776 
    777 /*
    778  * Callback for "new locals table entry". "signature" is an empty string
    779  * if no signature is available for an entry.
    780  */
    781 typedef void (*DexDebugNewLocalCb)(void *cnxt, u2 reg, u4 startAddress,
    782         u4 endAddress, const char *name, const char *descriptor,
    783         const char *signature);
    784 
    785 /*
    786  * Decode debug info for method.
    787  *
    788  * posCb is called in ascending address order.
    789  * localCb is called in order of ascending end address.
    790  */
    791 void dexDecodeDebugInfo(
    792             const DexFile* pDexFile,
    793             const DexCode* pDexCode,
    794             const char* classDescriptor,
    795             u4 protoIdx,
    796             u4 accessFlags,
    797             DexDebugNewPositionCb posCb, DexDebugNewLocalCb localCb,
    798             void* cnxt);
    799 
    800 /* DexClassDef convenience - get class descriptor */
    801 DEX_INLINE const char* dexGetClassDescriptor(const DexFile* pDexFile,
    802     const DexClassDef* pClassDef)
    803 {
    804     return dexStringByTypeIdx(pDexFile, pClassDef->classIdx);
    805 }
    806 
    807 /* DexClassDef convenience - get superclass descriptor */
    808 DEX_INLINE const char* dexGetSuperClassDescriptor(const DexFile* pDexFile,
    809     const DexClassDef* pClassDef)
    810 {
    811     if (pClassDef->superclassIdx == 0)
    812         return NULL;
    813     return dexStringByTypeIdx(pDexFile, pClassDef->superclassIdx);
    814 }
    815 
    816 /* DexClassDef convenience - get class_data_item pointer */
    817 DEX_INLINE const u1* dexGetClassData(const DexFile* pDexFile,
    818     const DexClassDef* pClassDef)
    819 {
    820     if (pClassDef->classDataOff == 0)
    821         return NULL;
    822     return (const u1*) (pDexFile->baseAddr + pClassDef->classDataOff);
    823 }
    824 
    825 /* Get an annotation set at a particular offset. */
    826 DEX_INLINE const DexAnnotationSetItem* dexGetAnnotationSetItem(
    827     const DexFile* pDexFile, u4 offset)
    828 {
    829     return (const DexAnnotationSetItem*) (pDexFile->baseAddr + offset);
    830 }
    831 /* get the class' annotation set */
    832 DEX_INLINE const DexAnnotationSetItem* dexGetClassAnnotationSet(
    833     const DexFile* pDexFile, const DexAnnotationsDirectoryItem* pAnnoDir)
    834 {
    835     if (pAnnoDir->classAnnotationsOff == 0)
    836         return NULL;
    837     return dexGetAnnotationSetItem(pDexFile, pAnnoDir->classAnnotationsOff);
    838 }
    839 
    840 /* get the class' field annotation list */
    841 DEX_INLINE const DexFieldAnnotationsItem* dexGetFieldAnnotations(
    842     const DexFile* pDexFile, const DexAnnotationsDirectoryItem* pAnnoDir)
    843 {
    844     if (pAnnoDir->fieldsSize == 0)
    845         return NULL;
    846 
    847     // Skip past the header to the start of the field annotations.
    848     return (const DexFieldAnnotationsItem*) &pAnnoDir[1];
    849 }
    850 
    851 /* get field annotation list size */
    852 DEX_INLINE int dexGetFieldAnnotationsSize(const DexFile* pDexFile,
    853     const DexAnnotationsDirectoryItem* pAnnoDir)
    854 {
    855     return pAnnoDir->fieldsSize;
    856 }
    857 
    858 /* return a pointer to the field's annotation set */
    859 DEX_INLINE const DexAnnotationSetItem* dexGetFieldAnnotationSetItem(
    860     const DexFile* pDexFile, const DexFieldAnnotationsItem* pItem)
    861 {
    862     return dexGetAnnotationSetItem(pDexFile, pItem->annotationsOff);
    863 }
    864 
    865 /* get the class' method annotation list */
    866 DEX_INLINE const DexMethodAnnotationsItem* dexGetMethodAnnotations(
    867     const DexFile* pDexFile, const DexAnnotationsDirectoryItem* pAnnoDir)
    868 {
    869     if (pAnnoDir->methodsSize == 0)
    870         return NULL;
    871 
    872     /*
    873      * Skip past the header and field annotations to the start of the
    874      * method annotations.
    875      */
    876     const u1* addr = (const u1*) &pAnnoDir[1];
    877     addr += pAnnoDir->fieldsSize * sizeof (DexFieldAnnotationsItem);
    878     return (const DexMethodAnnotationsItem*) addr;
    879 }
    880 
    881 /* get method annotation list size */
    882 DEX_INLINE int dexGetMethodAnnotationsSize(const DexFile* pDexFile,
    883     const DexAnnotationsDirectoryItem* pAnnoDir)
    884 {
    885     return pAnnoDir->methodsSize;
    886 }
    887 
    888 /* return a pointer to the method's annotation set */
    889 DEX_INLINE const DexAnnotationSetItem* dexGetMethodAnnotationSetItem(
    890     const DexFile* pDexFile, const DexMethodAnnotationsItem* pItem)
    891 {
    892     return dexGetAnnotationSetItem(pDexFile, pItem->annotationsOff);
    893 }
    894 
    895 /* get the class' parameter annotation list */
    896 DEX_INLINE const DexParameterAnnotationsItem* dexGetParameterAnnotations(
    897     const DexFile* pDexFile, const DexAnnotationsDirectoryItem* pAnnoDir)
    898 {
    899     if (pAnnoDir->parametersSize == 0)
    900         return NULL;
    901 
    902     /*
    903      * Skip past the header, field annotations, and method annotations
    904      * to the start of the parameter annotations.
    905      */
    906     const u1* addr = (const u1*) &pAnnoDir[1];
    907     addr += pAnnoDir->fieldsSize * sizeof (DexFieldAnnotationsItem);
    908     addr += pAnnoDir->methodsSize * sizeof (DexMethodAnnotationsItem);
    909     return (const DexParameterAnnotationsItem*) addr;
    910 }
    911 
    912 /* get method annotation list size */
    913 DEX_INLINE int dexGetParameterAnnotationsSize(const DexFile* pDexFile,
    914     const DexAnnotationsDirectoryItem* pAnnoDir)
    915 {
    916     return pAnnoDir->parametersSize;
    917 }
    918 
    919 /* return the parameter annotation ref list */
    920 DEX_INLINE const DexAnnotationSetRefList* dexGetParameterAnnotationSetRefList(
    921     const DexFile* pDexFile, const DexParameterAnnotationsItem* pItem)
    922 {
    923     return (const DexAnnotationSetRefList*)
    924         (pDexFile->baseAddr + pItem->annotationsOff);
    925 }
    926 
    927 /* get method annotation list size */
    928 DEX_INLINE int dexGetParameterAnnotationSetRefSize(const DexFile* pDexFile,
    929     const DexParameterAnnotationsItem* pItem)
    930 {
    931     if (pItem->annotationsOff == 0)
    932         return 0;
    933     return dexGetParameterAnnotationSetRefList(pDexFile, pItem)->size;
    934 }
    935 
    936 /* return the Nth entry from an annotation set ref list */
    937 DEX_INLINE const DexAnnotationSetRefItem* dexGetParameterAnnotationSetRef(
    938     const DexAnnotationSetRefList* pList, u4 idx)
    939 {
    940     assert(idx < pList->size);
    941     return &pList->list[idx];
    942 }
    943 
    944 /* given a DexAnnotationSetRefItem, return the DexAnnotationSetItem */
    945 DEX_INLINE const DexAnnotationSetItem* dexGetSetRefItemItem(
    946     const DexFile* pDexFile, const DexAnnotationSetRefItem* pItem)
    947 {
    948     return dexGetAnnotationSetItem(pDexFile, pItem->annotationsOff);
    949 }
    950 
    951 /* return the Nth annotation offset from a DexAnnotationSetItem */
    952 DEX_INLINE u4 dexGetAnnotationOff(
    953     const DexAnnotationSetItem* pAnnoSet, u4 idx)
    954 {
    955     assert(idx < pAnnoSet->size);
    956     return pAnnoSet->entries[idx];
    957 }
    958 
    959 /* return the Nth annotation item from a DexAnnotationSetItem */
    960 DEX_INLINE const DexAnnotationItem* dexGetAnnotationItem(
    961     const DexFile* pDexFile, const DexAnnotationSetItem* pAnnoSet, u4 idx)
    962 {
    963     return (const DexAnnotationItem*)
    964         (pDexFile->baseAddr + dexGetAnnotationOff(pAnnoSet, idx));
    965 }
    966 
    967 
    968 /*
    969  * ===========================================================================
    970  *      Utility Functions
    971  * ===========================================================================
    972  */
    973 
    974 /*
    975  * Retrieve the next UTF-16 character from a UTF-8 string.
    976  *
    977  * Advances "*pUtf8Ptr" to the start of the next character.
    978  *
    979  * WARNING: If a string is corrupted by dropping a '\0' in the middle
    980  * of a 3-byte sequence, you can end up overrunning the buffer with
    981  * reads (and possibly with the writes if the length was computed and
    982  * cached before the damage). For performance reasons, this function
    983  * assumes that the string being parsed is known to be valid (e.g., by
    984  * already being verified). Most strings we process here are coming
    985  * out of dex files or other internal translations, so the only real
    986  * risk comes from the JNI NewStringUTF call.
    987  */
    988 DEX_INLINE u2 dexGetUtf16FromUtf8(const char** pUtf8Ptr)
    989 {
    990     unsigned int one, two, three;
    991 
    992     one = *(*pUtf8Ptr)++;
    993     if ((one & 0x80) != 0) {
    994         /* two- or three-byte encoding */
    995         two = *(*pUtf8Ptr)++;
    996         if ((one & 0x20) != 0) {
    997             /* three-byte encoding */
    998             three = *(*pUtf8Ptr)++;
    999             return ((one & 0x0f) << 12) |
   1000                    ((two & 0x3f) << 6) |
   1001                    (three & 0x3f);
   1002         } else {
   1003             /* two-byte encoding */
   1004             return ((one & 0x1f) << 6) |
   1005                    (two & 0x3f);
   1006         }
   1007     } else {
   1008         /* one-byte encoding */
   1009         return one;
   1010     }
   1011 }
   1012 
   1013 /* Compare two '\0'-terminated modified UTF-8 strings, using Unicode
   1014  * code point values for comparison. This treats different encodings
   1015  * for the same code point as equivalent, except that only a real '\0'
   1016  * byte is considered the string terminator. The return value is as
   1017  * for strcmp(). */
   1018 int dexUtf8Cmp(const char* s1, const char* s2);
   1019 
   1020 
   1021 /* for dexIsValidMemberNameUtf8(), a bit vector indicating valid low ascii */
   1022 extern u4 DEX_MEMBER_VALID_LOW_ASCII[4];
   1023 
   1024 /* Helper for dexIsValidMemberUtf8(); do not call directly. */
   1025 bool dexIsValidMemberNameUtf8_0(const char** pUtf8Ptr);
   1026 
   1027 /* Return whether the pointed-at modified-UTF-8 encoded character is
   1028  * valid as part of a member name, updating the pointer to point past
   1029  * the consumed character. This will consume two encoded UTF-16 code
   1030  * points if the character is encoded as a surrogate pair. Also, if
   1031  * this function returns false, then the given pointer may only have
   1032  * been partially advanced. */
   1033 DEX_INLINE bool dexIsValidMemberNameUtf8(const char** pUtf8Ptr) {
   1034     u1 c = (u1) **pUtf8Ptr;
   1035     if (c <= 0x7f) {
   1036         // It's low-ascii, so check the table.
   1037         u4 wordIdx = c >> 5;
   1038         u4 bitIdx = c & 0x1f;
   1039         (*pUtf8Ptr)++;
   1040         return (DEX_MEMBER_VALID_LOW_ASCII[wordIdx] & (1 << bitIdx)) != 0;
   1041     }
   1042 
   1043     /*
   1044      * It's a multibyte encoded character. Call a non-inline function
   1045      * for the heavy lifting.
   1046      */
   1047     return dexIsValidMemberNameUtf8_0(pUtf8Ptr);
   1048 }
   1049 
   1050 /* Return whether the given string is a valid field or method name. */
   1051 bool dexIsValidMemberName(const char* s);
   1052 
   1053 /* Return whether the given string is a valid type descriptor. */
   1054 bool dexIsValidTypeDescriptor(const char* s);
   1055 
   1056 /* Return whether the given string is a valid reference descriptor. This
   1057  * is true if dexIsValidTypeDescriptor() returns true and the descriptor
   1058  * is for a class or array and not a primitive type. */
   1059 bool dexIsReferenceDescriptor(const char* s);
   1060 
   1061 /* Return whether the given string is a valid class descriptor. This
   1062  * is true if dexIsValidTypeDescriptor() returns true and the descriptor
   1063  * is for a class and not an array or primitive type. */
   1064 bool dexIsClassDescriptor(const char* s);
   1065 
   1066 /* Return whether the given string is a valid field type descriptor. This
   1067  * is true if dexIsValidTypeDescriptor() returns true and the descriptor
   1068  * is for anything but "void". */
   1069 bool dexIsFieldDescriptor(const char* s);
   1070 
   1071 #endif /*_LIBDEX_DEXFILE*/
   1072