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 1.53 2008/08/02 03:50:39 drh 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   sqlite3_aggregate_count,

   128   sqlite3_bind_blob,

   129   sqlite3_bind_double,

   130   sqlite3_bind_int,

   131   sqlite3_bind_int64,

   132   sqlite3_bind_null,

   133   sqlite3_bind_parameter_count,

   134   sqlite3_bind_parameter_index,

   135   sqlite3_bind_parameter_name,

   136   sqlite3_bind_text,

   137   sqlite3_bind_text16,

   138   sqlite3_bind_value,

   139   sqlite3_busy_handler,

   140   sqlite3_busy_timeout,

   141   sqlite3_changes,

   142   sqlite3_close,

   143   sqlite3_collation_needed,

   144   sqlite3_collation_needed16,

   145   sqlite3_column_blob,

   146   sqlite3_column_bytes,

   147   sqlite3_column_bytes16,

   148   sqlite3_column_count,

   149   sqlite3_column_database_name,

   150   sqlite3_column_database_name16,

   151   sqlite3_column_decltype,

   152   sqlite3_column_decltype16,

   153   sqlite3_column_double,

   154   sqlite3_column_int,

   155   sqlite3_column_int64,

   156   sqlite3_column_name,

   157   sqlite3_column_name16,

   158   sqlite3_column_origin_name,

   159   sqlite3_column_origin_name16,

   160   sqlite3_column_table_name,

   161   sqlite3_column_table_name16,

   162   sqlite3_column_text,

   163   sqlite3_column_text16,

   164   sqlite3_column_type,

   165   sqlite3_column_value,

   166   sqlite3_commit_hook,

   167   sqlite3_complete,

   168   sqlite3_complete16,

   169   sqlite3_create_collation,

   170   sqlite3_create_collation16,

   171   sqlite3_create_function,

   172   sqlite3_create_function16,

   173   sqlite3_create_module,

   174   sqlite3_data_count,

   175   sqlite3_db_handle,

   176   sqlite3_declare_vtab,

   177   sqlite3_enable_shared_cache,

   178   sqlite3_errcode,

   179   sqlite3_errmsg,

   180   sqlite3_errmsg16,

   181   sqlite3_exec,

   182   sqlite3_expired,

   183   sqlite3_finalize,

   184   sqlite3_free,

   185   sqlite3_free_table,

   186   sqlite3_get_autocommit,

   187   sqlite3_get_auxdata,

   188   sqlite3_get_table,

   189   0,     /* Was sqlite3_global_recover(), but that function is deprecated */

   190   sqlite3_interrupt,

   191   sqlite3_last_insert_rowid,

   192   sqlite3_libversion,

   193   sqlite3_libversion_number,

   194   sqlite3_malloc,

   195   sqlite3_mprintf,

   196   sqlite3_open,

   197   sqlite3_open16,

   198   sqlite3_prepare,

   199   sqlite3_prepare16,

   200   sqlite3_profile,

   201   sqlite3_progress_handler,

   202   sqlite3_realloc,

   203   sqlite3_reset,

   204   sqlite3_result_blob,

   205   sqlite3_result_double,

   206   sqlite3_result_error,

   207   sqlite3_result_error16,

   208   sqlite3_result_int,

   209   sqlite3_result_int64,

   210   sqlite3_result_null,

   211   sqlite3_result_text,

   212   sqlite3_result_text16,

   213   sqlite3_result_text16be,

   214   sqlite3_result_text16le,

   215   sqlite3_result_value,

   216   sqlite3_rollback_hook,

   217   sqlite3_set_authorizer,

   218   sqlite3_set_auxdata,

   219   sqlite3_snprintf,

   220   sqlite3_step,

   221   sqlite3_table_column_metadata,

   222   sqlite3_thread_cleanup,

   223   sqlite3_total_changes,

   224   sqlite3_trace,

   225   sqlite3_transfer_bindings,

   226   sqlite3_update_hook,

   227   sqlite3_user_data,

   228   sqlite3_value_blob,

   229   sqlite3_value_bytes,

   230   sqlite3_value_bytes16,

   231   sqlite3_value_double,

   232   sqlite3_value_int,

   233   sqlite3_value_int64,

   234   sqlite3_value_numeric_type,

   235   sqlite3_value_text,

   236   sqlite3_value_text16,

   237   sqlite3_value_text16be,

   238   sqlite3_value_text16le,

   239   sqlite3_value_type,

   240   sqlite3_vmprintf,

   241   /*

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

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

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

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

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

   247   *************************************************************************

   248   */

   249   sqlite3_overload_function,

   250 

   251   /*

   252   ** Added after 3.3.13

   253   */

   254   sqlite3_prepare_v2,

   255   sqlite3_prepare16_v2,

   256   sqlite3_clear_bindings,

   257 

   258   /*

   259   ** Added for 3.4.1

   260   */

   261   sqlite3_create_module_v2,

   262 

   263   /*

   264   ** Added for 3.5.0

   265   */

   266   sqlite3_bind_zeroblob,

   267   sqlite3_blob_bytes,

   268   sqlite3_blob_close,

   269   sqlite3_blob_open,

   270   sqlite3_blob_read,

   271   sqlite3_blob_write,

   272   sqlite3_create_collation_v2,

   273   sqlite3_file_control,

   274   sqlite3_memory_highwater,

   275   sqlite3_memory_used,

   276 #ifdef SQLITE_MUTEX_NOOP

   277   0, 

   278   0, 

   279   0,

   280   0,

   281   0,

   282 #else

   283   sqlite3_mutex_alloc,

   284   sqlite3_mutex_enter,

   285   sqlite3_mutex_free,

   286   sqlite3_mutex_leave,

   287   sqlite3_mutex_try,

   288 #endif

   289   sqlite3_open_v2,

   290   sqlite3_release_memory,

   291   sqlite3_result_error_nomem,

   292   sqlite3_result_error_toobig,

   293   sqlite3_sleep,

   294   sqlite3_soft_heap_limit,

   295   sqlite3_vfs_find,

   296   sqlite3_vfs_register,

   297   sqlite3_vfs_unregister,

   298 

   299   /*

   300   ** Added for 3.5.8

   301   */

   302   sqlite3_threadsafe,

   303   sqlite3_result_zeroblob,

   304   sqlite3_result_error_code,

   305   sqlite3_test_control,

   306   sqlite3_randomness,

   307   sqlite3_context_db_handle,

   308 

   309   /*

   310   ** Added for 3.6.0

   311   */

   312   sqlite3_extended_result_codes,

   313   sqlite3_limit,

   314   sqlite3_next_stmt,

   315   sqlite3_sql,

   316   sqlite3_status,

   317 };

   318 

   319 /*

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

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

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

   323 ** of the default name is recommended.

   324 **

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

   326 **

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

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

   329 ** by calling sqlite3DbFree(db, ).

   330 */

   331 static int sqlite3LoadExtension(

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

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

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

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

   336 ){

   337   sqlite3_vfs *pVfs = db->pVfs;

   338   void *handle;

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

   340   char *zErrmsg = 0;

   341   void **aHandle;

   342 

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

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

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

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

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

   348   */

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

   350     if( pzErrMsg ){

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

   352     }

   353     return SQLITE_ERROR;

   354   }

   355 

   356   if( zProc==0 ){

   357     zProc = "sqlite3_extension_init";

   358   }

   359 

   360   handle = sqlite3OsDlOpen(pVfs, zFile);

   361   if( handle==0 ){

   362     if( pzErrMsg ){

   363       char zErr[256];

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

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

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

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

   368       *pzErrMsg = sqlite3DbStrDup(0, zErr);

   369     }

   370     return SQLITE_ERROR;

   371   }

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

   373                    sqlite3OsDlSym(pVfs, handle, zProc);

   374   if( xInit==0 ){

   375     if( pzErrMsg ){

   376       char zErr[256];

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

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

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

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

   381       *pzErrMsg = sqlite3DbStrDup(0, zErr);

   382       sqlite3OsDlClose(pVfs, handle);

   383     }

   384     return SQLITE_ERROR;

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

   386     if( pzErrMsg ){

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

   388     }

   389     sqlite3_free(zErrmsg);

   390     sqlite3OsDlClose(pVfs, handle);

   391     return SQLITE_ERROR;

   392   }

   393 

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

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

   396   if( aHandle==0 ){

   397     return SQLITE_NOMEM;

   398   }

   399   if( db->nExtension>0 ){

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

   401   }

   402   sqlite3DbFree(db, db->aExtension);

   403   db->aExtension = aHandle;

   404 

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

   406   return SQLITE_OK;

   407 }

   408 int sqlite3_load_extension(

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

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

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

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

   413 ){

   414   int rc;

   415   sqlite3_mutex_enter(db->mutex);

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

   417   sqlite3_mutex_leave(db->mutex);

   418   return rc;

   419 }

   420 

   421 /*

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

   423 ** to clean up loaded extensions

   424 */

   425 void sqlite3CloseExtensions(sqlite3 *db){

   426   int i;

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

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

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

   430   }

   431   sqlite3DbFree(db, db->aExtension);

   432 }

   433 

   434 /*

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

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

   437 */

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

   439   sqlite3_mutex_enter(db->mutex);

   440   if( onoff ){

   441     db->flags |= SQLITE_LoadExtension;

   442   }else{

   443     db->flags &= ~SQLITE_LoadExtension;

   444   }

   445   sqlite3_mutex_leave(db->mutex);

   446   return SQLITE_OK;

   447 }

   448 

   449 #endif /* SQLITE_OMIT_LOAD_EXTENSION */

   450 

   451 /*

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

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

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

   455 ** dummy pointer.

   456 */

   457 #ifdef SQLITE_OMIT_LOAD_EXTENSION

   458 static const sqlite3_api_routines sqlite3Apis = { 0 };

   459 #endif

   460 

   461 

   462 /*

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

   464 ** extensions.

   465 **

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

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

   468 */

   469 static struct {

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

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

   472 } autoext = { 0, 0 };

   473 

   474 

   475 /*

   476 ** Register a statically linked extension that is automatically

   477 ** loaded by every new database connection.

   478 */

   479 int sqlite3_auto_extension(void *xInit){

   480   int rc = SQLITE_OK;

   481 #ifndef SQLITE_OMIT_AUTOINIT

   482   rc = sqlite3_initialize();

   483   if( rc ){

   484     return rc;

   485   }else

   486 #endif

   487   {

   488     int i;

   489 #ifndef SQLITE_MUTEX_NOOP

   490     sqlite3_mutex *mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER);

   491 #endif

   492     sqlite3_mutex_enter(mutex);

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

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

   495     }

   496     if( i==autoext.nExt ){

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

   498       void **aNew;

   499       aNew = sqlite3_realloc(autoext.aExt, nByte);

   500       if( aNew==0 ){

   501         rc = SQLITE_NOMEM;

   502       }else{

   503         autoext.aExt = aNew;

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

   505         autoext.nExt++;

   506       }

   507     }

   508     sqlite3_mutex_leave(mutex);

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

   510     return rc;

   511   }

   512 }

   513 

   514 /*

   515 ** Reset the automatic extension loading mechanism.

   516 */

   517 void sqlite3_reset_auto_extension(void){

   518 #ifndef SQLITE_OMIT_AUTOINIT

   519   if( sqlite3_initialize()==SQLITE_OK )

   520 #endif

   521   {

   522 #ifndef SQLITE_MUTEX_NOOP

   523     sqlite3_mutex *mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER);

   524 #endif

   525     sqlite3_mutex_enter(mutex);

   526     sqlite3_free(autoext.aExt);

   527     autoext.aExt = 0;

   528     autoext.nExt = 0;

   529     sqlite3_mutex_leave(mutex);

   530   }

   531 }

   532 

   533 /*

   534 ** Load all automatic extensions.

   535 */

   536 int sqlite3AutoLoadExtensions(sqlite3 *db){

   537   int i;

   538   int go = 1;

   539   int rc = SQLITE_OK;

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

   541 

   542   if( autoext.nExt==0 ){

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

   544     return SQLITE_OK;

   545   }

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

   547     char *zErrmsg = 0;

   548 #ifndef SQLITE_MUTEX_NOOP

   549     sqlite3_mutex *mutex = sqlite3MutexAlloc(SQLITE_MUTEX_STATIC_MASTER);

   550 #endif

   551     sqlite3_mutex_enter(mutex);

   552     if( i>=autoext.nExt ){

   553       xInit = 0;

   554       go = 0;

   555     }else{

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

   557               autoext.aExt[i];

   558     }

   559     sqlite3_mutex_leave(mutex);

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

   561       sqlite3Error(db, SQLITE_ERROR,

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

   563       go = 0;

   564       rc = SQLITE_ERROR;

   565       sqlite3_free(zErrmsg);

   566     }

   567   }

   568   return rc;

   569 }