1 files changed, 211 insertions, 11 deletions

diff --git a/src/crypto.c b/src/crypto.c
index 50213b5..2551e6b 100644
--- a/src/crypto.c
+++ b/src/crypto.c
@@ -1,10 +1,8 @@
 /* 
 ** SQLCipher
-** crypto.c developed by Stephen Lombardo (Zetetic LLC) 
-** sjlombardo at zetetic dot net
-** http://zetetic.net
+** http://sqlcipher.net
 ** 
-** Copyright (c) 2009, ZETETIC LLC
+** Copyright (c) 2008 - 2013, ZETETIC LLC
 ** All rights reserved.
 ** 
 ** Redistribution and use in source and binary forms, with or without
@@ -30,7 +28,7 @@
 ** SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 **  
 */
-/* BEGIN CRYPTO */
+/* BEGIN SQLCIPHER */
 #ifdef SQLITE_HAS_CODEC
 
 #include <assert.h>
@@ -38,12 +36,12 @@
 #include "btreeInt.h"
 #include "crypto.h"
 
-const char* codec_get_cipher_version() {
+static const char* codec_get_cipher_version() {
   return CIPHER_VERSION;
 }
 
 /* Generate code to return a string value */
-void codec_vdbe_return_static_string(Parse *pParse, const char *zLabel, const char *value){
+static void codec_vdbe_return_static_string(Parse *pParse, const char *zLabel, const char *value){
   Vdbe *v = sqlite3GetVdbe(pParse);
   sqlite3VdbeSetNumCols(v, 1);
   sqlite3VdbeSetColName(v, 0, COLNAME_NAME, zLabel, SQLITE_STATIC);
@@ -69,7 +67,7 @@ static int codec_set_btree_to_codec_pagesize(sqlite3 *db, Db *pDb, codec_ctx *ct
   return rc;
 }
 
-int codec_set_pass_key(sqlite3* db, int nDb, const void *zKey, int nKey, int for_ctx) {
+static int codec_set_pass_key(sqlite3* db, int nDb, const void *zKey, int nKey, int for_ctx) {
   struct Db *pDb = &db->aDb[nDb];
   CODEC_TRACE(("codec_set_pass_key: entered db=%p nDb=%d zKey=%s nKey=%d for_ctx=%d\n", db, nDb, (char *)zKey, nKey, for_ctx));
   if(pDb->pBt) {
@@ -91,6 +89,11 @@ int codec_pragma(sqlite3* db, int iDb, Parse *pParse, const char *zLeft, const c
 
   CODEC_TRACE(("codec_pragma: entered db=%p iDb=%d pParse=%p zLeft=%s zRight=%s ctx=%p\n", db, iDb, pParse, zLeft, zRight, ctx));
 
+  if( sqlite3StrICmp(zLeft, "cipher_provider")==0 && !zRight ){
+    if(ctx) { codec_vdbe_return_static_string(pParse, "cipher_provider",
+                                              sqlcipher_codec_get_cipher_provider(ctx));
+    }
+  } else
   if( sqlite3StrICmp(zLeft, "cipher_version")==0 && !zRight ){
     codec_vdbe_return_static_string(pParse, "cipher_version", codec_get_cipher_version());
   }else
@@ -291,13 +294,13 @@ int sqlite3CodecAttach(sqlite3* db, int nDb, const void *zKey, int nKey) {
 
     sqlcipher_activate(); /* perform internal initialization for sqlcipher */
 
+    sqlite3_mutex_enter(db->mutex);
+
     /* point the internal codec argument against the contet to be prepared */
     rc = sqlcipher_codec_ctx_init(&ctx, pDb, pDb->pBt->pBt->pPager, fd, zKey, nKey); 
 
     if(rc != SQLITE_OK) return rc; /* initialization failed, do not attach potentially corrupted context */
 
-    sqlite3_mutex_enter(db->mutex);
-
     sqlite3pager_sqlite3PagerSetCodec(sqlite3BtreePager(pDb->pBt), sqlite3Codec, NULL, sqlite3FreeCodecArg, (void *) ctx);
 
     codec_set_btree_to_codec_pagesize(db, pDb, ctx);
@@ -423,6 +426,203 @@ void sqlite3CodecGetKey(sqlite3* db, int nDb, void **zKey, int *nKey) {
   }
 }
 
+#ifndef OMIT_EXPORT
+
+/*
+ * Implementation of an "export" function that allows a caller
+ * to duplicate the main database to an attached database. This is intended
+ * as a conveneince for users who need to:
+ * 
+ *   1. migrate from an non-encrypted database to an encrypted database
+ *   2. move from an encrypted database to a non-encrypted database
+ *   3. convert beween the various flavors of encrypted databases.  
+ *
+ * This implementation is based heavily on the procedure and code used
+ * in vacuum.c, but is exposed as a function that allows export to any
+ * named attached database.
+ */
+
+/*
+** Finalize a prepared statement.  If there was an error, store the
+** text of the error message in *pzErrMsg.  Return the result code.
+** 
+** Based on vacuumFinalize from vacuum.c
+*/
+static int sqlcipher_finalize(sqlite3 *db, sqlite3_stmt *pStmt, char **pzErrMsg){
+  int rc;
+  rc = sqlite3VdbeFinalize((Vdbe*)pStmt);
+  if( rc ){
+    sqlite3SetString(pzErrMsg, db, sqlite3_errmsg(db));
+  }
+  return rc;
+}
+
+/*
+** Execute zSql on database db. Return an error code.
+** 
+** Based on execSql from vacuum.c
+*/
+static int sqlcipher_execSql(sqlite3 *db, char **pzErrMsg, const char *zSql){
+  sqlite3_stmt *pStmt;
+  VVA_ONLY( int rc; )
+  if( !zSql ){
+    return SQLITE_NOMEM;
+  }
+  if( SQLITE_OK!=sqlite3_prepare(db, zSql, -1, &pStmt, 0) ){
+    sqlite3SetString(pzErrMsg, db, sqlite3_errmsg(db));
+    return sqlite3_errcode(db);
+  }
+  VVA_ONLY( rc = ) sqlite3_step(pStmt);
+  assert( rc!=SQLITE_ROW );
+  return sqlcipher_finalize(db, pStmt, pzErrMsg);
+}
+
+/*
+** Execute zSql on database db. The statement returns exactly
+** one column. Execute this as SQL on the same database.
+** 
+** Based on execExecSql from vacuum.c
+*/
+static int sqlcipher_execExecSql(sqlite3 *db, char **pzErrMsg, const char *zSql){
+  sqlite3_stmt *pStmt;
+  int rc;
+
+  rc = sqlite3_prepare(db, zSql, -1, &pStmt, 0);
+  if( rc!=SQLITE_OK ) return rc;
+
+  while( SQLITE_ROW==sqlite3_step(pStmt) ){
+    rc = sqlcipher_execSql(db, pzErrMsg, (char*)sqlite3_column_text(pStmt, 0));
+    if( rc!=SQLITE_OK ){
+      sqlcipher_finalize(db, pStmt, pzErrMsg);
+      return rc;
+    }
+  }
+
+  return sqlcipher_finalize(db, pStmt, pzErrMsg);
+}
+
+/*
+ * copy database and schema from the main database to an attached database
+ * 
+ * Based on sqlite3RunVacuum from vacuum.c
+*/
+void sqlcipher_exportFunc(sqlite3_context *context, int argc, sqlite3_value **argv) {
+  sqlite3 *db = sqlite3_context_db_handle(context);
+  const char* attachedDb = (const char*) sqlite3_value_text(argv[0]);
+  int saved_flags;        /* Saved value of the db->flags */
+  int saved_nChange;      /* Saved value of db->nChange */
+  int saved_nTotalChange; /* Saved value of db->nTotalChange */
+  void (*saved_xTrace)(void*,const char*);  /* Saved db->xTrace */
+  int rc = SQLITE_OK;     /* Return code from service routines */
+  char *zSql = NULL;         /* SQL statements */
+  char *pzErrMsg = NULL;
+  
+  saved_flags = db->flags;
+  saved_nChange = db->nChange;
+  saved_nTotalChange = db->nTotalChange;
+  saved_xTrace = db->xTrace;
+  db->flags |= SQLITE_WriteSchema | SQLITE_IgnoreChecks | SQLITE_PreferBuiltin;
+  db->flags &= ~(SQLITE_ForeignKeys | SQLITE_ReverseOrder);
+  db->xTrace = 0;
+
+  /* Query the schema of the main database. Create a mirror schema
+  ** in the temporary database.
+  */
+  zSql = sqlite3_mprintf(
+    "SELECT 'CREATE TABLE %s.' || substr(sql,14) "
+    "  FROM sqlite_master WHERE type='table' AND name!='sqlite_sequence'"
+    "   AND rootpage>0"
+  , attachedDb);
+  rc = (zSql == NULL) ? SQLITE_NOMEM : sqlcipher_execExecSql(db, &pzErrMsg, zSql); 
+  if( rc!=SQLITE_OK ) goto end_of_export;
+  sqlite3_free(zSql);
+
+  zSql = sqlite3_mprintf(
+    "SELECT 'CREATE INDEX %s.' || substr(sql,14)"
+    "  FROM sqlite_master WHERE sql LIKE 'CREATE INDEX %%' "
+  , attachedDb);
+  rc = (zSql == NULL) ? SQLITE_NOMEM : sqlcipher_execExecSql(db, &pzErrMsg, zSql); 
+  if( rc!=SQLITE_OK ) goto end_of_export;
+  sqlite3_free(zSql);
+
+  zSql = sqlite3_mprintf(
+    "SELECT 'CREATE UNIQUE INDEX %s.' || substr(sql,21) "
+    "  FROM sqlite_master WHERE sql LIKE 'CREATE UNIQUE INDEX %%'"
+  , attachedDb);
+  rc = (zSql == NULL) ? SQLITE_NOMEM : sqlcipher_execExecSql(db, &pzErrMsg, zSql); 
+  if( rc!=SQLITE_OK ) goto end_of_export;
+  sqlite3_free(zSql);
+
+  /* Loop through the tables in the main database. For each, do
+  ** an "INSERT INTO rekey_db.xxx SELECT * FROM main.xxx;" to copy
+  ** the contents to the temporary database.
+  */
+  zSql = sqlite3_mprintf(
+    "SELECT 'INSERT INTO %s.' || quote(name) "
+    "|| ' SELECT * FROM main.' || quote(name) || ';'"
+    "FROM main.sqlite_master "
+    "WHERE type = 'table' AND name!='sqlite_sequence' "
+    "  AND rootpage>0"
+  , attachedDb);
+  rc = (zSql == NULL) ? SQLITE_NOMEM : sqlcipher_execExecSql(db, &pzErrMsg, zSql); 
+  if( rc!=SQLITE_OK ) goto end_of_export;
+  sqlite3_free(zSql);
+
+  /* Copy over the sequence table
+  */
+  zSql = sqlite3_mprintf(
+    "SELECT 'DELETE FROM %s.' || quote(name) || ';' "
+    "FROM %s.sqlite_master WHERE name='sqlite_sequence' "
+  , attachedDb, attachedDb);
+  rc = (zSql == NULL) ? SQLITE_NOMEM : sqlcipher_execExecSql(db, &pzErrMsg, zSql); 
+  if( rc!=SQLITE_OK ) goto end_of_export;
+  sqlite3_free(zSql);
+
+  zSql = sqlite3_mprintf(
+    "SELECT 'INSERT INTO %s.' || quote(name) "
+    "|| ' SELECT * FROM main.' || quote(name) || ';' "
+    "FROM %s.sqlite_master WHERE name=='sqlite_sequence';"
+  , attachedDb, attachedDb);
+  rc = (zSql == NULL) ? SQLITE_NOMEM : sqlcipher_execExecSql(db, &pzErrMsg, zSql); 
+  if( rc!=SQLITE_OK ) goto end_of_export;
+  sqlite3_free(zSql);
+
+  /* Copy the triggers, views, and virtual tables from the main database
+  ** over to the temporary database.  None of these objects has any
+  ** associated storage, so all we have to do is copy their entries
+  ** from the SQLITE_MASTER table.
+  */
+  zSql = sqlite3_mprintf(
+    "INSERT INTO %s.sqlite_master "
+    "  SELECT type, name, tbl_name, rootpage, sql"
+    "    FROM main.sqlite_master"
+    "   WHERE type='view' OR type='trigger'"
+    "      OR (type='table' AND rootpage=0)"
+  , attachedDb);
+  rc = (zSql == NULL) ? SQLITE_NOMEM : sqlcipher_execSql(db, &pzErrMsg, zSql); 
+  if( rc!=SQLITE_OK ) goto end_of_export;
+  sqlite3_free(zSql);
+
+  zSql = NULL;
+end_of_export:
+  db->flags = saved_flags;
+  db->nChange = saved_nChange;
+  db->nTotalChange = saved_nTotalChange;
+  db->xTrace = saved_xTrace;
+
+  sqlite3_free(zSql);
+
+  if(rc) {
+    if(pzErrMsg != NULL) {
+      sqlite3_result_error(context, pzErrMsg, -1);
+      sqlite3DbFree(db, pzErrMsg);
+    } else {
+      sqlite3_result_error(context, sqlite3ErrStr(rc), -1);
+    }
+  }
+}
+
+#endif
 
-/* END CRYPTO */
+/* END SQLCIPHER */
 #endif