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 #ifndef SQLITE_OMIT_LOAD_EXTENSION

    16 

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

    18 #include "sqlite3ext.h"

    19 #include "sqliteInt.h"

    20 #include <string.h>

    21 #include <ctype.h>

    22 

    23 /*

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

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

    26 ** for any missing APIs.

    27 */

    28 #ifndef SQLITE_ENABLE_COLUMN_METADATA

    29 # define sqlite3_column_database_name   0

    30 # define sqlite3_column_database_name16 0

    31 # define sqlite3_column_table_name      0

    32 # define sqlite3_column_table_name16    0

    33 # define sqlite3_column_origin_name     0

    34 # define sqlite3_column_origin_name16   0

    35 # define sqlite3_table_column_metadata  0

    36 #endif

    37 

    38 #ifdef SQLITE_OMIT_AUTHORIZATION

    39 # define sqlite3_set_authorizer         0

    40 #endif

    41 

    42 #ifdef SQLITE_OMIT_UTF16

    43 # define sqlite3_bind_text16            0

    44 # define sqlite3_collation_needed16     0

    45 # define sqlite3_column_decltype16      0

    46 # define sqlite3_column_name16          0

    47 # define sqlite3_column_text16          0

    48 # define sqlite3_complete16             0

    49 # define sqlite3_create_collation16     0

    50 # define sqlite3_create_function16      0

    51 # define sqlite3_errmsg16               0

    52 # define sqlite3_open16                 0

    53 # define sqlite3_prepare16              0

    54 # define sqlite3_prepare16_v2           0

    55 # define sqlite3_result_error16         0

    56 # define sqlite3_result_text16          0

    57 # define sqlite3_result_text16be        0

    58 # define sqlite3_result_text16le        0

    59 # define sqlite3_value_text16           0

    60 # define sqlite3_value_text16be         0

    61 # define sqlite3_value_text16le         0

    62 # define sqlite3_column_database_name16 0

    63 # define sqlite3_column_table_name16    0

    64 # define sqlite3_column_origin_name16   0

    65 #endif

    66 

    67 #ifdef SQLITE_OMIT_COMPLETE

    68 # define sqlite3_complete 0

    69 # define sqlite3_complete16 0

    70 #endif

    71 

    72 #ifdef SQLITE_OMIT_PROGRESS_CALLBACK

    73 # define sqlite3_progress_handler 0

    74 #endif

    75 

    76 #ifdef SQLITE_OMIT_VIRTUALTABLE

    77 # define sqlite3_create_module 0

    78 # define sqlite3_create_module_v2 0

    79 # define sqlite3_declare_vtab 0

    80 #endif

    81 

    82 #ifdef SQLITE_OMIT_SHARED_CACHE

    83 # define sqlite3_enable_shared_cache 0

    84 #endif

    85 

    86 #ifdef SQLITE_OMIT_TRACE

    87 # define sqlite3_profile       0

    88 # define sqlite3_trace         0

    89 #endif

    90 

    91 #ifdef SQLITE_OMIT_GET_TABLE

    92 # define sqlite3_free_table    0

    93 # define sqlite3_get_table     0

    94 #endif

    95 

    96 #ifdef SQLITE_OMIT_INCRBLOB

    97 #define sqlite3_bind_zeroblob  0

    98 #define sqlite3_blob_bytes     0

    99 #define sqlite3_blob_close     0

   100 #define sqlite3_blob_open      0

   101 #define sqlite3_blob_read      0

   102 #define sqlite3_blob_write     0

   103 #endif

   104 

   105 /*

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

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

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

   109 ** library.

   110 **

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

   112 ** in order to preserve backwards compatibility.

   113 **

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

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

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

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

   118 ** not NULL before calling it.

   119 */

   120 const sqlite3_api_routines sqlite3_apis = {

   121   sqlite3_aggregate_context,

   122   sqlite3_aggregate_count,

   123   sqlite3_bind_blob,

   124   sqlite3_bind_double,

   125   sqlite3_bind_int,

   126   sqlite3_bind_int64,

   127   sqlite3_bind_null,

   128   sqlite3_bind_parameter_count,

   129   sqlite3_bind_parameter_index,

   130   sqlite3_bind_parameter_name,

   131   sqlite3_bind_text,

   132   sqlite3_bind_text16,

   133   sqlite3_bind_value,

   134   sqlite3_busy_handler,

   135   sqlite3_busy_timeout,

   136   sqlite3_changes,

   137   sqlite3_close,

   138   sqlite3_collation_needed,

   139   sqlite3_collation_needed16,

   140   sqlite3_column_blob,

   141   sqlite3_column_bytes,

   142   sqlite3_column_bytes16,

   143   sqlite3_column_count,

   144   sqlite3_column_database_name,

   145   sqlite3_column_database_name16,

   146   sqlite3_column_decltype,

   147   sqlite3_column_decltype16,

   148   sqlite3_column_double,

   149   sqlite3_column_int,

   150   sqlite3_column_int64,

   151   sqlite3_column_name,

   152   sqlite3_column_name16,

   153   sqlite3_column_origin_name,

   154   sqlite3_column_origin_name16,

   155   sqlite3_column_table_name,

   156   sqlite3_column_table_name16,

   157   sqlite3_column_text,

   158   sqlite3_column_text16,

   159   sqlite3_column_type,

   160   sqlite3_column_value,

   161   sqlite3_commit_hook,

   162   sqlite3_complete,

   163   sqlite3_complete16,

   164   sqlite3_create_collation,

   165   sqlite3_create_collation16,

   166   sqlite3_create_function,

   167   sqlite3_create_function16,

   168   sqlite3_create_module,

   169   sqlite3_data_count,

   170   sqlite3_db_handle,

   171   sqlite3_declare_vtab,

   172   sqlite3_enable_shared_cache,

   173   sqlite3_errcode,

   174   sqlite3_errmsg,

   175   sqlite3_errmsg16,

   176   sqlite3_exec,

   177   sqlite3_expired,

   178   sqlite3_finalize,

   179   sqlite3_free,

   180   sqlite3_free_table,

   181   sqlite3_get_autocommit,

   182   sqlite3_get_auxdata,

   183   sqlite3_get_table,

   184   0,     /* Was sqlite3_global_recover(), but that function is deprecated */

   185   sqlite3_interrupt,

   186   sqlite3_last_insert_rowid,

   187   sqlite3_libversion,

   188   sqlite3_libversion_number,

   189   sqlite3_malloc,

   190   sqlite3_mprintf,

   191   sqlite3_open,

   192   sqlite3_open16,

   193   sqlite3_prepare,

   194   sqlite3_prepare16,

   195   sqlite3_profile,

   196   sqlite3_progress_handler,

   197   sqlite3_realloc,

   198   sqlite3_reset,

   199   sqlite3_result_blob,

   200   sqlite3_result_double,

   201   sqlite3_result_error,

   202   sqlite3_result_error16,

   203   sqlite3_result_int,

   204   sqlite3_result_int64,

   205   sqlite3_result_null,

   206   sqlite3_result_text,

   207   sqlite3_result_text16,

   208   sqlite3_result_text16be,

   209   sqlite3_result_text16le,

   210   sqlite3_result_value,

   211   sqlite3_rollback_hook,

   212   sqlite3_set_authorizer,

   213   sqlite3_set_auxdata,

   214   sqlite3_snprintf,

   215   sqlite3_step,

   216   sqlite3_table_column_metadata,

   217   sqlite3_thread_cleanup,

   218   sqlite3_total_changes,

   219   sqlite3_trace,

   220   sqlite3_transfer_bindings,

   221   sqlite3_update_hook,

   222   sqlite3_user_data,

   223   sqlite3_value_blob,

   224   sqlite3_value_bytes,

   225   sqlite3_value_bytes16,

   226   sqlite3_value_double,

   227   sqlite3_value_int,

   228   sqlite3_value_int64,

   229   sqlite3_value_numeric_type,

   230   sqlite3_value_text,

   231   sqlite3_value_text16,

   232   sqlite3_value_text16be,

   233   sqlite3_value_text16le,

   234   sqlite3_value_type,

   235   sqlite3_vmprintf,

   236   /*

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

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

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

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

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

   242   *************************************************************************

   243   */

   244   sqlite3_overload_function,

   245 

   246   /*

   247   ** Added after 3.3.13

   248   */

   249   sqlite3_prepare_v2,

   250   sqlite3_prepare16_v2,

   251   sqlite3_clear_bindings,

   252 

   253   /*

   254   ** Added for 3.4.1

   255   */

   256   sqlite3_create_module_v2,

   257 

   258   /*

   259   ** Added for 3.5.0

   260   */

   261   sqlite3_bind_zeroblob,

   262   sqlite3_blob_bytes,

   263   sqlite3_blob_close,

   264   sqlite3_blob_open,

   265   sqlite3_blob_read,

   266   sqlite3_blob_write,

   267   sqlite3_create_collation_v2,

   268   sqlite3_file_control,

   269   sqlite3_memory_highwater,

   270   sqlite3_memory_used,

   271 #ifdef SQLITE_MUTEX_NOOP

   272   0, 

   273   0, 

   274   0,

   275   0,

   276   0,

   277 #else

   278   sqlite3_mutex_alloc,

   279   sqlite3_mutex_enter,

   280   sqlite3_mutex_free,

   281   sqlite3_mutex_leave,

   282   sqlite3_mutex_try,

   283 #endif

   284   sqlite3_open_v2,

   285   sqlite3_release_memory,

   286   sqlite3_result_error_nomem,

   287   sqlite3_result_error_toobig,

   288   sqlite3_sleep,

   289   sqlite3_soft_heap_limit,

   290   sqlite3_vfs_find,

   291   sqlite3_vfs_register,

   292   sqlite3_vfs_unregister,

   293 };

   294 

   295 /*

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

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

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

   299 ** of the default name is recommended.

   300 **

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

   302 **

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

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

   305 ** by calling sqlite3_free().

   306 */

   307 static int sqlite3LoadExtension(

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

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

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

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

   312 ){

   313   sqlite3_vfs *pVfs = db->pVfs;

   314   void *handle;

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

   316   char *zErrmsg = 0;

   317   void **aHandle;

   318 

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

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

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

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

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

   324   */

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

   326     if( pzErrMsg ){

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

   328     }

   329     return SQLITE_ERROR;

   330   }

   331 

   332   if( zProc==0 ){

   333     zProc = "sqlite3_extension_init";

   334   }

   335 

   336   handle = sqlite3OsDlOpen(pVfs, zFile);

   337   if( handle==0 ){

   338     if( pzErrMsg ){

   339       char zErr[256];

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

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

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

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

   344       *pzErrMsg = sqlite3DbStrDup(db, zErr);

   345     }

   346     return SQLITE_ERROR;

   347   }

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

   349                    sqlite3OsDlSym(pVfs, handle, zProc);

   350   if( xInit==0 ){

   351     if( pzErrMsg ){

   352       char zErr[256];

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

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

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

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

   357       *pzErrMsg = sqlite3DbStrDup(db, zErr);

   358       sqlite3OsDlClose(pVfs, handle);

   359     }

   360     return SQLITE_ERROR;

   361   }else if( xInit(db, &zErrmsg, &sqlite3_apis) ){

   362     if( pzErrMsg ){

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

   364     }

   365     sqlite3_free(zErrmsg);

   366     sqlite3OsDlClose(pVfs, handle);

   367     return SQLITE_ERROR;

   368   }

   369 

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

   371   db->nExtension++;

   372   aHandle = (void**)sqlite3DbMallocZero(db, sizeof(handle)*db->nExtension);

   373   if( aHandle==0 ){

   374     return SQLITE_NOMEM;

   375   }

   376   if( db->nExtension>0 ){

   377     memcpy(aHandle, db->aExtension, sizeof(handle)*(db->nExtension-1));

   378   }

   379   sqlite3_free(db->aExtension);

   380   db->aExtension = aHandle;

   381 

   382   db->aExtension[db->nExtension-1] = handle;

   383   return SQLITE_OK;

   384 }

   385 EXPORT_C int sqlite3_load_extension(

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

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

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

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

   390 ){

   391   int rc;

   392   sqlite3_mutex_enter(db->mutex);

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

   394   sqlite3_mutex_leave(db->mutex);

   395   return rc;

   396 }

   397 

   398 /*

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

   400 ** to clean up loaded extensions

   401 */

   402 void sqlite3CloseExtensions(sqlite3 *db){

   403   int i;

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

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

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

   407   }

   408   sqlite3_free(db->aExtension);

   409 }

   410 

   411 /*

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

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

   414 */

   415 EXPORT_C int sqlite3_enable_load_extension(sqlite3 *db, int onoff){

   416   sqlite3_mutex_enter(db->mutex);

   417   if( onoff ){

   418     db->flags |= SQLITE_LoadExtension;

   419   }else{

   420     db->flags &= ~SQLITE_LoadExtension;

   421   }

   422   sqlite3_mutex_leave(db->mutex);

   423   return SQLITE_OK;

   424 }

   425 

   426 /*

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

   428 ** extensions.

   429 **

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

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

   432 */

   433 static struct {

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

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

   436 } autoext = { 0, 0 };

   437 

   438 

   439 /*

   440 ** Register a statically linked extension that is automatically

   441 ** loaded by every new database connection.

   442 */

   443 EXPORT_C int sqlite3_auto_extension(void *xInit){

   444   int i;

   445   int rc = SQLITE_OK;

   446   sqlite3_mutex *mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER);

   447   sqlite3_mutex_enter(mutex);

   448   for(i=0; i<autoext.nExt; i++){

   449     if( autoext.aExt[i]==xInit ) break;

   450   }

   451   if( i==autoext.nExt ){

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

   453     void **aNew;

   454     aNew = (void**)sqlite3_realloc(autoext.aExt, nByte);

   455     if( aNew==0 ){

   456       rc = SQLITE_NOMEM;

   457     }else{

   458       autoext.aExt = aNew;

   459       autoext.aExt[autoext.nExt] = xInit;

   460       autoext.nExt++;

   461     }

   462   }

   463   sqlite3_mutex_leave(mutex);

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

   465   return rc;

   466 }

   467 

   468 /*

   469 ** Reset the automatic extension loading mechanism.

   470 */

   471 EXPORT_C void sqlite3_reset_auto_extension(void){

   472   sqlite3_mutex *mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER);

   473   sqlite3_mutex_enter(mutex);

   474   sqlite3_free(autoext.aExt);

   475   autoext.aExt = 0;

   476   autoext.nExt = 0;

   477   sqlite3_mutex_leave(mutex);

   478 }

   479 

   480 /*

   481 ** Load all automatic extensions.

   482 */

   483 int sqlite3AutoLoadExtensions(sqlite3 *db){

   484   int i;

   485   int go = 1;

   486   int rc = SQLITE_OK;

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

   488 

   489   if( autoext.nExt==0 ){

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

   491     return SQLITE_OK;

   492   }

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

   494     char *zErrmsg = 0;

   495     sqlite3_mutex *mutex = sqlite3_mutex_alloc(SQLITE_MUTEX_STATIC_MASTER);

   496     sqlite3_mutex_enter(mutex);

   497     if( i>=autoext.nExt ){

   498       xInit = 0;

   499       go = 0;

   500     }else{

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

   502               autoext.aExt[i];

   503     }

   504     sqlite3_mutex_leave(mutex);

   505     if( xInit && xInit(db, &zErrmsg, &sqlite3_apis) ){

   506       sqlite3Error(db, SQLITE_ERROR,

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

   508       go = 0;

   509       rc = SQLITE_ERROR;

   510       sqlite3_free(zErrmsg);

   511     }

   512   }

   513   return rc;

   514 }

   515 

   516 #endif /* SQLITE_OMIT_LOAD_EXTENSION */