1 /*

     2 ** 2006 June 7

     3 **

     4 ** The author disclaims copyright to this source code.  In place of

     5 ** a legal notice, here is a blessing:

     6 **

     7 **    May you do good and not evil.

     8 **    May you find forgiveness for yourself and forgive others.

     9 **    May you share freely, never taking more than you give.

    10 **

    11 *************************************************************************

    12 ** This file contains code used to dynamically load extensions into

    13 ** the SQLite library.

    14 **

    15 ** $Id: loadext.c,v 1.56 2008/10/12 00:27:53 shane Exp $

    16 */

    17 

    18 #ifndef SQLITE_CORE

    19   #define SQLITE_CORE 1  /* Disable the API redefinition in sqlite3ext.h */

    20 #endif

    21 #include "sqlite3ext.h"

    22 #include "sqliteInt.h"

    23 #include <string.h>

    24 #include <ctype.h>

    25 

    26 #ifndef SQLITE_OMIT_LOAD_EXTENSION

    27 

    28 /*

    29 ** Some API routines are omitted when various features are

    30 ** excluded from a build of SQLite.  Substitute a NULL pointer

    31 ** for any missing APIs.

    32 */

    33 #ifndef SQLITE_ENABLE_COLUMN_METADATA

    34 # define sqlite3_column_database_name   0

    35 # define sqlite3_column_database_name16 0

    36 # define sqlite3_column_table_name      0

    37 # define sqlite3_column_table_name16    0

    38 # define sqlite3_column_origin_name     0

    39 # define sqlite3_column_origin_name16   0

    40 # define sqlite3_table_column_metadata  0

    41 #endif

    42 

    43 #ifdef SQLITE_OMIT_AUTHORIZATION

    44 # define sqlite3_set_authorizer         0

    45 #endif

    46 

    47 #ifdef SQLITE_OMIT_UTF16

    48 # define sqlite3_bind_text16            0

    49 # define sqlite3_collation_needed16     0

    50 # define sqlite3_column_decltype16      0

    51 # define sqlite3_column_name16          0

    52 # define sqlite3_column_text16          0

    53 # define sqlite3_complete16             0

    54 # define sqlite3_create_collation16     0

    55 # define sqlite3_create_function16      0

    56 # define sqlite3_errmsg16               0

    57 # define sqlite3_open16                 0

    58 # define sqlite3_prepare16              0

    59 # define sqlite3_prepare16_v2           0

    60 # define sqlite3_result_error16         0

    61 # define sqlite3_result_text16          0

    62 # define sqlite3_result_text16be        0

    63 # define sqlite3_result_text16le        0

    64 # define sqlite3_value_text16           0

    65 # define sqlite3_value_text16be         0

    66 # define sqlite3_value_text16le         0

    67 # define sqlite3_column_database_name16 0

    68 # define sqlite3_column_table_name16    0

    69 # define sqlite3_column_origin_name16   0

    70 #endif

    71 

    72 #ifdef SQLITE_OMIT_COMPLETE

    73 # define sqlite3_complete 0

    74 # define sqlite3_complete16 0

    75 #endif

    76 

    77 #ifdef SQLITE_OMIT_PROGRESS_CALLBACK

    78 # define sqlite3_progress_handler 0

    79 #endif

    80 

    81 #ifdef SQLITE_OMIT_VIRTUALTABLE

    82 # define sqlite3_create_module 0

    83 # define sqlite3_create_module_v2 0

    84 # define sqlite3_declare_vtab 0

    85 #endif

    86 

    87 #ifdef SQLITE_OMIT_SHARED_CACHE

    88 # define sqlite3_enable_shared_cache 0

    89 #endif

    90 

    91 #ifdef SQLITE_OMIT_TRACE

    92 # define sqlite3_profile       0

    93 # define sqlite3_trace         0

    94 #endif

    95 

    96 #ifdef SQLITE_OMIT_GET_TABLE

    97 # define sqlite3_free_table    0

    98 # define sqlite3_get_table     0

    99 #endif

   100 

   101 #ifdef SQLITE_OMIT_INCRBLOB

   102 #define sqlite3_bind_zeroblob  0

   103 #define sqlite3_blob_bytes     0

   104 #define sqlite3_blob_close     0

   105 #define sqlite3_blob_open      0

   106 #define sqlite3_blob_read      0

   107 #define sqlite3_blob_write     0

   108 #endif

   109 

   110 /*

   111 ** The following structure contains pointers to all SQLite API routines.

   112 ** A pointer to this structure is passed into extensions when they are

   113 ** loaded so that the extension can make calls back into the SQLite

   114 ** library.

   115 **

   116 ** When adding new APIs, add them to the bottom of this structure

   117 ** in order to preserve backwards compatibility.

   118 **

   119 ** Extensions that use newer APIs should first call the

   120 ** sqlite3_libversion_number() to make sure that the API they

   121 ** intend to use is supported by the library.  Extensions should

   122 ** also check to make sure that the pointer to the function is

   123 ** not NULL before calling it.

   124 */

   125 static const sqlite3_api_routines sqlite3Apis = {

   126   sqlite3_aggregate_context,

   127 #ifndef SQLITE_OMIT_DEPRECATED

   128   sqlite3_aggregate_count,

   129 #else

   130   0,

   131 #endif

   132   sqlite3_bind_blob,

   133   sqlite3_bind_double,

   134   sqlite3_bind_int,

   135   sqlite3_bind_int64,

   136   sqlite3_bind_null,

   137   sqlite3_bind_parameter_count,

   138   sqlite3_bind_parameter_index,

   139   sqlite3_bind_parameter_name,

   140   sqlite3_bind_text,

   141   sqlite3_bind_text16,

   142   sqlite3_bind_value,

   143   sqlite3_busy_handler,

   144   sqlite3_busy_timeout,

   145   sqlite3_changes,

   146   sqlite3_close,

   147   sqlite3_collation_needed,

   148   sqlite3_collation_needed16,

   149   sqlite3_column_blob,

   150   sqlite3_column_bytes,

   151   sqlite3_column_bytes16,

   152   sqlite3_column_count,

   153   sqlite3_column_database_name,

   154   sqlite3_column_database_name16,

   155   sqlite3_column_decltype,

   156   sqlite3_column_decltype16,

   157   sqlite3_column_double,

   158   sqlite3_column_int,

   159   sqlite3_column_int64,

   160   sqlite3_column_name,

   161   sqlite3_column_name16,

   162   sqlite3_column_origin_name,

   163   sqlite3_column_origin_name16,

   164   sqlite3_column_table_name,

   165   sqlite3_column_table_name16,

   166   sqlite3_column_text,

   167   sqlite3_column_text16,

   168   sqlite3_column_type,

   169   sqlite3_column_value,

   170   sqlite3_commit_hook,

   171   sqlite3_complete,

   172   sqlite3_complete16,

   173   sqlite3_create_collation,

   174   sqlite3_create_collation16,

   175   sqlite3_create_function,

   176   sqlite3_create_function16,

   177   sqlite3_create_module,

   178   sqlite3_data_count,

   179   sqlite3_db_handle,

   180   sqlite3_declare_vtab,

   181   sqlite3_enable_shared_cache,

   182   sqlite3_errcode,

   183   sqlite3_errmsg,

   184   sqlite3_errmsg16,

   185   sqlite3_exec,

   186 #ifndef SQLITE_OMIT_DEPRECATED

   187   sqlite3_expired,

   188 #else

   189   0,

   190 #endif

   191   sqlite3_finalize,

   192   sqlite3_free,

   193   sqlite3_free_table,

   194   sqlite3_get_autocommit,

   195   sqlite3_get_auxdata,

   196   sqlite3_get_table,

   197   0,     /* Was sqlite3_global_recover(), but that function is deprecated */

   198   sqlite3_interrupt,

   199   sqlite3_last_insert_rowid,

   200   sqlite3_libversion,

   201   sqlite3_libversion_number,

   202   sqlite3_malloc,

   203   sqlite3_mprintf,

   204   sqlite3_open,

   205   sqlite3_open16,

   206   sqlite3_prepare,

   207   sqlite3_prepare16,

   208   sqlite3_profile,

   209   sqlite3_progress_handler,

   210   sqlite3_realloc,

   211   sqlite3_reset,

   212   sqlite3_result_blob,

   213   sqlite3_result_double,

   214   sqlite3_result_error,

   215   sqlite3_result_error16,

   216   sqlite3_result_int,

   217   sqlite3_result_int64,

   218   sqlite3_result_null,

   219   sqlite3_result_text,

   220   sqlite3_result_text16,

   221   sqlite3_result_text16be,

   222   sqlite3_result_text16le,

   223   sqlite3_result_value,

   224   sqlite3_rollback_hook,

   225   sqlite3_set_authorizer,

   226   sqlite3_set_auxdata,

   227   sqlite3_snprintf,

   228   sqlite3_step,

   229   sqlite3_table_column_metadata,

   230 #ifndef SQLITE_OMIT_DEPRECATED

   231   sqlite3_thread_cleanup,

   232 #else

   233   0,

   234 #endif

   235   sqlite3_total_changes,

   236   sqlite3_trace,

   237 #ifndef SQLITE_OMIT_DEPRECATED

   238   sqlite3_transfer_bindings,

   239 #else

   240   0,

   241 #endif

   242   sqlite3_update_hook,

   243   sqlite3_user_data,

   244   sqlite3_value_blob,

   245   sqlite3_value_bytes,

   246   sqlite3_value_bytes16,

   247   sqlite3_value_double,

   248   sqlite3_value_int,

   249   sqlite3_value_int64,

   250   sqlite3_value_numeric_type,

   251   sqlite3_value_text,

   252   sqlite3_value_text16,

   253   sqlite3_value_text16be,

   254   sqlite3_value_text16le,

   255   sqlite3_value_type,

   256   sqlite3_vmprintf,

   257   /*

   258   ** The original API set ends here.  All extensions can call any

   259   ** of the APIs above provided that the pointer is not NULL.  But

   260   ** before calling APIs that follow, extension should check the

   261   ** sqlite3_libversion_number() to make sure they are dealing with

   262   ** a library that is new enough to support that API.

   263   *************************************************************************

   264   */

   265   sqlite3_overload_function,

   266 

   267   /*

   268   ** Added after 3.3.13

   269   */

   270   sqlite3_prepare_v2,

   271   sqlite3_prepare16_v2,

   272   sqlite3_clear_bindings,

   273 

   274   /*

   275   ** Added for 3.4.1

   276   */

   277   sqlite3_create_module_v2,

   278 

   279   /*

   280   ** Added for 3.5.0

   281   */

   282   sqlite3_bind_zeroblob,

   283   sqlite3_blob_bytes,

   284   sqlite3_blob_close,

   285   sqlite3_blob_open,

   286   sqlite3_blob_read,

   287   sqlite3_blob_write,

   288   sqlite3_create_collation_v2,

   289   sqlite3_file_control,

   290   sqlite3_memory_highwater,

   291   sqlite3_memory_used,

   292 #ifdef SQLITE_MUTEX_OMIT

   293   0, 

   294   0, 

   295   0,

   296   0,

   297   0,

   298 #else

   299   sqlite3_mutex_alloc,

   300   sqlite3_mutex_enter,

   301   sqlite3_mutex_free,

   302   sqlite3_mutex_leave,

   303   sqlite3_mutex_try,

   304 #endif

   305   sqlite3_open_v2,

   306   sqlite3_release_memory,

   307   sqlite3_result_error_nomem,

   308   sqlite3_result_error_toobig,

   309   sqlite3_sleep,

   310   sqlite3_soft_heap_limit,

   311   sqlite3_vfs_find,

   312   sqlite3_vfs_register,

   313   sqlite3_vfs_unregister,

   314 

   315   /*

   316   ** Added for 3.5.8

   317   */

   318   sqlite3_threadsafe,

   319   sqlite3_result_zeroblob,

   320   sqlite3_result_error_code,

   321   sqlite3_test_control,

   322   sqlite3_randomness,

   323   sqlite3_context_db_handle,

   324 

   325   /*

   326   ** Added for 3.6.0

   327   */

   328   sqlite3_extended_result_codes,

   329   sqlite3_limit,

   330   sqlite3_next_stmt,

   331   sqlite3_sql,

   332   sqlite3_status,

   333 };

   334 

   335 /*

   336 ** Attempt to load an SQLite extension library contained in the file

   337 ** zFile.  The entry point is zProc.  zProc may be 0 in which case a

   338 ** default entry point name (sqlite3_extension_init) is used.  Use

   339 ** of the default name is recommended.

   340 **

   341 ** Return SQLITE_OK on success and SQLITE_ERROR if something goes wrong.

   342 **

   343 ** If an error occurs and pzErrMsg is not 0, then fill *pzErrMsg with 

   344 ** error message text.  The calling function should free this memory

   345 ** by calling sqlite3DbFree(db, ).

   346 */

   347 static int sqlite3LoadExtension(

   348   sqlite3 *db,          /* Load the extension into this database connection */

   349   const char *zFile,    /* Name of the shared library containing extension */

   350   const char *zProc,    /* Entry point.  Use "sqlite3_extension_init" if 0 */

   351   char **pzErrMsg       /* Put error message here if not 0 */

   352 ){

   353   sqlite3_vfs *pVfs = db->pVfs;

   354   void *handle;

   355   int (*xInit)(sqlite3*,char**,const sqlite3_api_routines*);

   356   char *zErrmsg = 0;

   357   void **aHandle;

   358 

   359   /* Ticket #1863.  To avoid a creating security problems for older

   360   ** applications that relink against newer versions of SQLite, the

   361   ** ability to run load_extension is turned off by default.  One

   362   ** must call sqlite3_enable_load_extension() to turn on extension

   363   ** loading.  Otherwise you get the following error.

   364   */

   365   if( (db->flags & SQLITE_LoadExtension)==0 ){

   366     if( pzErrMsg ){

   367       *pzErrMsg = sqlite3_mprintf("not authorized");

   368     }

   369     return SQLITE_ERROR;

   370   }

   371 

   372   if( zProc==0 ){

   373     zProc = "sqlite3_extension_init";

   374   }

   375 

   376   handle = sqlite3OsDlOpen(pVfs, zFile);

   377   if( handle==0 ){

   378     if( pzErrMsg ){

   379       char zErr[256];

   380       zErr[sizeof(zErr)-1] = '\0';

   381       sqlite3_snprintf(sizeof(zErr)-1, zErr, 

   382           "unable to open shared library [%s]", zFile);

   383       sqlite3OsDlError(pVfs, sizeof(zErr)-1, zErr);

   384       *pzErrMsg = sqlite3DbStrDup(0, zErr);

   385     }

   386     return SQLITE_ERROR;

   387   }

   388   xInit = (int(*)(sqlite3*,char**,const sqlite3_api_routines*))

   389                    sqlite3OsDlSym(pVfs, handle, zProc);

   390   if( xInit==0 ){

   391     if( pzErrMsg ){

   392       char zErr[256];

   393       zErr[sizeof(zErr)-1] = '\0';

   394       sqlite3_snprintf(sizeof(zErr)-1, zErr,

   395           "no entry point [%s] in shared library [%s]", zProc,zFile);

   396       sqlite3OsDlError(pVfs, sizeof(zErr)-1, zErr);

   397       *pzErrMsg = sqlite3DbStrDup(0, zErr);

   398       sqlite3OsDlClose(pVfs, handle);

   399     }

   400     return SQLITE_ERROR;

   401   }else if( xInit(db, &zErrmsg, &sqlite3Apis) ){

   402     if( pzErrMsg ){

   403       *pzErrMsg = sqlite3_mprintf("error during initialization: %s", zErrmsg);

   404     }

   405     sqlite3_free(zErrmsg);

   406     sqlite3OsDlClose(pVfs, handle);

   407     return SQLITE_ERROR;

   408   }

   409 

   410   /* Append the new shared library handle to the db->aExtension array. */

   411   aHandle = sqlite3DbMallocZero(db, sizeof(handle)*(db->nExtension+1));

   412   if( aHandle==0 ){

   413     return SQLITE_NOMEM;

   414   }

   415   if( db->nExtension>0 ){

   416     memcpy(aHandle, db->aExtension, sizeof(handle)*db->nExtension);

   417   }

   418   sqlite3DbFree(db, db->aExtension);

   419   db->aExtension = aHandle;

   420 

   421   db->aExtension[db->nExtension++] = handle;

   422   return SQLITE_OK;

   423 }

   424 int sqlite3_load_extension(

   425   sqlite3 *db,          /* Load the extension into this database connection */

   426   const char *zFile,    /* Name of the shared library containing extension */

   427   const char *zProc,    /* Entry point.  Use "sqlite3_extension_init" if 0 */

   428   char **pzErrMsg       /* Put error message here if not 0 */

   429 ){

   430   int rc;

   431   sqlite3_mutex_enter(db->mutex);

   432   rc = sqlite3LoadExtension(db, zFile, zProc, pzErrMsg);

   433   sqlite3_mutex_leave(db->mutex);

   434   return rc;

   435 }

   436 

   437 /*

   438 ** Call this routine when the database connection is closing in order

   439 ** to clean up loaded extensions

   440 */

   441 void sqlite3CloseExtensions(sqlite3 *db){

   442   int i;

   443   assert( sqlite3_mutex_held(db->mutex) );

   444   for(i=0; i<db->nExtension; i++){

   445     sqlite3OsDlClose(db->pVfs, db->aExtension[i]);

   446   }

   447   sqlite3DbFree(db, db->aExtension);

   448 }

   449 

   450 /*

   451 ** Enable or disable extension loading.  Extension loading is disabled by

   452 ** default so as not to open security holes in older applications.

   453 */

   454 int sqlite3_enable_load_extension(sqlite3 *db, int onoff){

   455   sqlite3_mutex_enter(db->mutex);

   456   if( onoff ){

   457     db->flags |= SQLITE_LoadExtension;

   458   }else{

   459     db->flags &= ~SQLITE_LoadExtension;

   460   }

   461   sqlite3_mutex_leave(db->mutex);

   462   return SQLITE_OK;

   463 }

   464 

   465 #endif /* SQLITE_OMIT_LOAD_EXTENSION */

   466 

   467 /*

   468 ** The auto-extension code added regardless of whether or not extension

   469 ** loading is supported.  We need a dummy sqlite3Apis pointer for that

   470 ** code if regular extension loading is not available.  This is that

   471 ** dummy pointer.

   472 */

   473 #ifdef SQLITE_OMIT_LOAD_EXTENSION

   474 static const sqlite3_api_routines sqlite3Apis = { 0 };

   475 #endif

   476 

   477 

   478 /*

   479 ** The following object holds the list of automatically loaded

   480 ** extensions.

   481 **

   482 ** This list is shared across threads.  The SQLITE_MUTEX_STATIC_MASTER

   483 ** mutex must be held while accessing this list.

   484 */

   485 typedef struct sqlite3ExtType sqlite3ExtType;

   486 static SQLITE_WSD struct sqlite3ExtType {

   487   int nExt;        /* Number of entries in aExt[] */          

   488   void **aExt;     /* Pointers to the extension init functions */

   489 } sqlite3Autoext = { 0, 0 };

   490 

   491 /* The "wsdAutoext" macro will resolve to the autoextension

   492 ** state vector.  If writable static data is unsupported on the target,

   493 ** we have to locate the state vector at run-time.  In the more common

   494 ** case where writable static data is supported, wsdStat can refer directly

   495 ** to the "sqlite3Autoext" state vector declared above.

   496 */

   497 #ifdef SQLITE_OMIT_WSD

   498 # define wsdAutoextInit \

   499   sqlite3ExtType *x = &GLOBAL(sqlite3ExtType,sqlite3Autoext)

   500 # define wsdAutoext x[0]

   501 #else

   502 # define wsdAutoextInit

   503 # define wsdAutoext sqlite3Autoext

   504 #endif

   505 

   506 

   507 /*

   508 ** Register a statically linked extension that is automatically

   509 ** loaded by every new database connection.

   510 */

   511 int sqlite3_auto_extension(void *xInit){

   512   int rc = SQLITE_OK;

   513 #ifndef SQLITE_OMIT_AUTOINIT

   514   rc = sqlite3_initialize();

   515   if( rc ){

   516     return rc;

   517   }else

   518 #endif

   519   {

   520     int i;

   521 #if SQLITE_THREADSAFE

   522     sqlite3_mutex *mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER);

   523 #endif

   524     wsdAutoextInit;

   525     sqlite3_mutex_enter(mutex);

   526     for(i=0; i<wsdAutoext.nExt; i++){

   527       if( wsdAutoext.aExt[i]==xInit ) break;

   528     }

   529     if( i==wsdAutoext.nExt ){

   530       int nByte = (wsdAutoext.nExt+1)*sizeof(wsdAutoext.aExt[0]);

   531       void **aNew;

   532       aNew = sqlite3_realloc(wsdAutoext.aExt, nByte);

   533       if( aNew==0 ){

   534         rc = SQLITE_NOMEM;

   535       }else{

   536         wsdAutoext.aExt = aNew;

   537         wsdAutoext.aExt[wsdAutoext.nExt] = xInit;

   538         wsdAutoext.nExt++;

   539       }

   540     }

   541     sqlite3_mutex_leave(mutex);

   542     assert( (rc&0xff)==rc );

   543     return rc;

   544   }

   545 }

   546 

   547 /*

   548 ** Reset the automatic extension loading mechanism.

   549 */

   550 void sqlite3_reset_auto_extension(void){

   551 #ifndef SQLITE_OMIT_AUTOINIT

   552   if( sqlite3_initialize()==SQLITE_OK )

   553 #endif

   554   {

   555 #if SQLITE_THREADSAFE

   556     sqlite3_mutex *mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER);

   557 #endif

   558     wsdAutoextInit;

   559     sqlite3_mutex_enter(mutex);

   560     sqlite3_free(wsdAutoext.aExt);

   561     wsdAutoext.aExt = 0;

   562     wsdAutoext.nExt = 0;

   563     sqlite3_mutex_leave(mutex);

   564   }

   565 }

   566 

   567 /*

   568 ** Load all automatic extensions.

   569 */

   570 int sqlite3AutoLoadExtensions(sqlite3 *db){

   571   int i;

   572   int go = 1;

   573   int rc = SQLITE_OK;

   574   int (*xInit)(sqlite3*,char**,const sqlite3_api_routines*);

   575 

   576   wsdAutoextInit;

   577   if( wsdAutoext.nExt==0 ){

   578     /* Common case: early out without every having to acquire a mutex */

   579     return SQLITE_OK;

   580   }

   581   for(i=0; go; i++){

   582     char *zErrmsg = 0;

   583 #if SQLITE_THREADSAFE

   584     sqlite3_mutex *mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER);

   585 #endif

   586     sqlite3_mutex_enter(mutex);

   587     if( i>=wsdAutoext.nExt ){

   588       xInit = 0;

   589       go = 0;

   590     }else{

   591       xInit = (int(*)(sqlite3*,char**,const sqlite3_api_routines*))

   592               wsdAutoext.aExt[i];

   593     }

   594     sqlite3_mutex_leave(mutex);

   595     if( xInit && xInit(db, &zErrmsg, &sqlite3Apis) ){

   596       sqlite3Error(db, SQLITE_ERROR,

   597             "automatic extension loading failed: %s", zErrmsg);

   598       go = 0;

   599       rc = SQLITE_ERROR;

   600       sqlite3_free(zErrmsg);

   601     }

   602   }

   603   return rc;

   604 }