int sqlite3CodecAttach(sqlite3* db, int nDb, const void* zKey, int nKey)
{
/* Attach a key to a database. */
Codec* codec = (Codec*) sqlite3_malloc(sizeof(Codec));
CodecInit(codec);
/* No key specified, could mean either use the main db's encryption or no encryption */
if (zKey == NULL || nKey <= 0)
{
/* No key specified */
if (nDb != 0 && nKey > 0)
{
Codec* mainCodec = (Codec*) mySqlite3PagerGetCodec(sqlite3BtreePager(db->aDb[0].pBt));
/* Attached database, therefore use the key of main database, if main database is encrypted */
if (mainCodec != NULL && CodecIsEncrypted(mainCodec))
{
CodecCopy(codec, mainCodec);
CodecSetBtree(codec, db->aDb[nDb].pBt);
#if (SQLITE_VERSION_NUMBER >= 3006016)
mySqlite3PagerSetCodec(sqlite3BtreePager(db->aDb[nDb].pBt), sqlite3Codec, sqlite3CodecSizeChange, sqlite3CodecFree, codec);
#else
#if (SQLITE_VERSION_NUMBER >= 3003014)
sqlite3PagerSetCodec(sqlite3BtreePager(db->aDb[nDb].pBt), sqlite3Codec, codec);
#else
sqlite3pager_set_codec(sqlite3BtreePager(db->aDb[nDb].pBt), sqlite3Codec, codec);
#endif
db->aDb[nDb].pAux = codec;
db->aDb[nDb].xFreeAux = sqlite3CodecFree;
#endif
}
else
{
CodecSetIsEncrypted(codec, 0);
sqlite3_free(codec);
}
}
}
else
{
/* Key specified, setup encryption key for database */
CodecSetIsEncrypted(codec, 1);
CodecSetHasReadKey(codec, 1);
CodecSetHasWriteKey(codec, 1);
CodecGenerateReadKey(codec, (char*) zKey, nKey);
CodecCopyKey(codec, 1);
CodecSetBtree(codec, db->aDb[nDb].pBt);
#if (SQLITE_VERSION_NUMBER >= 3006016)
mySqlite3PagerSetCodec(sqlite3BtreePager(db->aDb[nDb].pBt), sqlite3Codec, sqlite3CodecSizeChange, sqlite3CodecFree, codec);
#else
#if (SQLITE_VERSION_NUMBER >= 3003014)
sqlite3PagerSetCodec(sqlite3BtreePager(db->aDb[nDb].pBt), sqlite3Codec, codec);
#else
sqlite3pager_set_codec(sqlite3BtreePager(db->aDb[nDb].pBt), sqlite3Codec, codec);
#endif
db->aDb[nDb].pAux = codec;
db->aDb[nDb].xFreeAux = sqlite3CodecFree;
#endif
}
return SQLITE_OK;
}
void sqlite3CodecGetKey(sqlite3* db, int nDb, void** zKey, int* nKey)
{
/*
// The unencrypted password is not stored for security reasons
// therefore always return NULL
// If the main database is encrypted a key length of 1 is returned.
// In that case an attached database will get the same encryption key
// as the main database if no key was explicitly given for the attached database.
*/
Codec* mainCodec = (Codec*) mySqlite3PagerGetCodec(sqlite3BtreePager(db->aDb[0].pBt));
int keylen = (mainCodec != NULL && CodecIsEncrypted(mainCodec)) ? 1 : 0;
*zKey = NULL;
*nKey = keylen;
}
int sqlite3_rekey_v2(sqlite3 *db, const char *zDbName, const void *zKey, int nKey)
{
/* Changes the encryption key for an existing database. */
int dbIndex = dbFindIndex(db, zDbName);
int rc = SQLITE_ERROR;
Btree* pbt = db->aDb[dbIndex].pBt;
Pager* pPager = sqlite3BtreePager(pbt);
Codec* codec = (Codec*) mySqlite3PagerGetCodec(pPager);
if ((zKey == NULL || nKey == 0) && (codec == NULL || !CodecIsEncrypted(codec)))
{
/*
// Database not encrypted and key not specified
// therefore do nothing
*/
return SQLITE_OK;
}
if (codec == NULL || !CodecIsEncrypted(codec))
{
/*
// Database not encrypted, but key specified
// therefore encrypt database
*/
if (codec == NULL)
{
codec = (Codec*) sqlite3_malloc(sizeof(Codec));
CodecInit(codec);
}
CodecSetIsEncrypted(codec, 1);
CodecSetHasReadKey(codec, 0); /* Original database is not encrypted */
CodecSetHasWriteKey(codec, 1);
CodecGenerateWriteKey(codec, (char*) zKey, nKey);
CodecSetBtree(codec, pbt);
#if (SQLITE_VERSION_NUMBER >= 3006016)
mySqlite3PagerSetCodec(pPager, sqlite3Codec, sqlite3CodecSizeChange, sqlite3CodecFree, codec);
#else
#if (SQLITE_VERSION_NUMBER >= 3003014)
sqlite3PagerSetCodec(pPager, sqlite3Codec, codec);
#else
sqlite3pager_set_codec(pPager, sqlite3Codec, codec);
#endif
db->aDb[dbIndex].pAux = codec;
db->aDb[dbIndex].xFreeAux = sqlite3CodecFree;
#endif
}
else if (zKey == NULL || nKey == 0)
{
/*
// Database encrypted, but key not specified
// therefore decrypt database
// Keep read key, drop write key
*/
CodecSetHasWriteKey(codec, 0);
}
else
{
/*
// Database encrypted and key specified
// therefore re-encrypt database with new key
// Keep read key, change write key to new key
*/
CodecGenerateWriteKey(codec, (char*) zKey, nKey);
CodecSetHasWriteKey(codec, 1);
}
sqlite3_mutex_enter(db->mutex);
/* Start transaction */
rc = sqlite3BtreeBeginTrans(pbt, 1);
if (!rc)
{
int pageSize = sqlite3BtreeGetPageSize(pbt);
Pgno nSkip = WX_PAGER_MJ_PGNO(pageSize);
#if (SQLITE_VERSION_NUMBER >= 3003014)
DbPage *pPage;
#else
void *pPage;
#endif
Pgno n;
/* Rewrite all pages using the new encryption key (if specified) */
#if (SQLITE_VERSION_NUMBER >= 3007001)
Pgno nPage;
int nPageCount = -1;
sqlite3PagerPagecount(pPager, &nPageCount);
nPage = nPageCount;
#elif (SQLITE_VERSION_NUMBER >= 3006000)
int nPageCount = -1;
int rc = sqlite3PagerPagecount(pPager, &nPageCount);
Pgno nPage = (Pgno) nPageCount;
#elif (SQLITE_VERSION_NUMBER >= 3003014)
Pgno nPage = sqlite3PagerPagecount(pPager);
#else
Pgno nPage = sqlite3pager_pagecount(pPager);
#endif
for (n = 1; rc == SQLITE_OK && n <= nPage; n++)
{
if (n == nSkip) continue;
#if (SQLITE_VERSION_NUMBER >= 3003014)
rc = sqlite3PagerGet(pPager, n, &pPage);
#else
rc = sqlite3pager_get(pPager, n, &pPage);
#endif
if (!rc)
{
#if (SQLITE_VERSION_NUMBER >= 3003014)
rc = sqlite3PagerWrite(pPage);
sqlite3PagerUnref(pPage);
#else
rc = sqlite3pager_write(pPage);
sqlite3pager_unref(pPage);
#endif
}
}
}
if (rc == SQLITE_OK)
{
/* Commit transaction if all pages could be rewritten */
rc = sqlite3BtreeCommit(pbt);
}
if (rc != SQLITE_OK)
{
/* Rollback in case of error */
#if (SQLITE_VERSION_NUMBER >= 3007011)
sqlite3BtreeRollback(pbt, SQLITE_OK);
#else
sqlite3BtreeRollback(pbt);
#endif
}
sqlite3_mutex_leave(db->mutex);
if (rc == SQLITE_OK)
{
/* Set read key equal to write key if necessary */
if (CodecHasWriteKey(codec))
{
CodecCopyKey(codec, 0);
CodecSetHasReadKey(codec, 1);
}
else
{
CodecSetIsEncrypted(codec, 0);
}
}
else
{
/* Restore write key if necessary */
if (CodecHasReadKey(codec))
{
CodecCopyKey(codec, 1);
}
else
{
CodecSetIsEncrypted(codec, 0);
}
}
if (!CodecIsEncrypted(codec))
{
/* Remove codec for unencrypted database */
#if (SQLITE_VERSION_NUMBER >= 3006016)
mySqlite3PagerSetCodec(pPager, NULL, NULL, NULL, NULL);
#else
#if (SQLITE_VERSION_NUMBER >= 3003014)
sqlite3PagerSetCodec(pPager, NULL, NULL);
#else
sqlite3pager_set_codec(pPager, NULL, NULL);
#endif
db->aDb[dbIndex].pAux = NULL;
db->aDb[dbIndex].xFreeAux = NULL;
sqlite3CodecFree(codec);
#endif
}
return rc;
}