SQLiteCrypt API
SQLiteCrypt is very easy to use. SQLiteCrypt is based on SQLite with all API functions remain unchanged. All encryption/ decryption routines are performed transparently. SQLiteCrypt uses three PRAGMA statements to work with encrypted database:
PRAGMA key = 'the passphrase' // passphrase
PRAGMA rekey = 'new passphrase' // change passphrase
PRAGMA lic = 'the license key' // the software key
The first PRAGMA statement is used to create/ access encrypted database. The second one will re-write database with new passphrase. The third one used to identify legal copy of SQLiteCrypt software.
Remark: Do not use rekey in middle of a transaction. This method decrypt whole database using old passphrase, then encrypt using new passphrase. You can continue to use SQLite API functions, no need of closing and re-opening database. This is time-consuming operation.
Example 1: Create/ open encrypted SQLite database
sqlite3_open_v2("data.db", &db, SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE, NULL);
sqlite3_stmt* stm;
const char *pzTail;
int res;
res = sqlite3_prepare(db, "PRAGMA key = 'ac23';", -1, &stm, &pzTail); //ac23
is database passphrase
res = sqlite3_step(stm);
res = sqlite3_prepare(db, "PRAGMA lic = '77523-009-0000007-72328';", -1, &stm, &pzTail); //software
license key
res = sqlite3_step(stm);
//now you have all access to data.db
Example 2: Decrypt SQLite database (remove encryption, so any other SQLite application can open it)
sqlite3_open_v2("data.db", &db, SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE, NULL);
sqlite3_stmt* stm;
const char *pzTail;
int res;
res = sqlite3_prepare(db, "PRAGMA key = 'ac23';", -1, &stm, &pzTail); //ac23
is current passphrase
res = sqlite3_step(stm);
res = sqlite3_prepare(db, "PRAGMA lic = '77523-009-0000007-72328';", -1, &stm, &pzTail); //software
license key
res = sqlite3_step(stm);
//now you have all access to encrypted data.db
res = sqlite3_prepare(db, "PRAGMA rekey = '';", -1, &stm, &pzTail); // new empty passphrase
res = sqlite3_step(stm);
//now data.db is NOT encrypted
Example 3: Change encryption key on-the-fly
sqlite3_open_v2("data.db", &db, SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE, NULL);
sqlite3_stmt* stm;
const char* pzTail;
int res;
res = sqlite3_prepare(db, "PRAGMA key = 'ac23';", -1, &stm, &pzTail); //ac23
is current passphrase
res = sqlite3_step(stm);
res = sqlite3_prepare(db, "PRAGMA lic = '77523-009-0000007-72328';", -1, &stm, &pzTail); //software
license key
res = sqlite3_step(stm);
//now you have all access to encrypted data.db
res = sqlite3_prepare(db, "PRAGMA rekey = 'abc123';", -1, &stm, &pzTail); //abc123
is new passphrase
res = sqlite3_step(stm);
//now data.db re-written using new passphrase
Example 4: Encrypt SQLite database (add encryption to regular SQLite database)
sqlite3_open_v2("data.db", &db, SQLITE_OPEN_READWRITE | SQLITE_OPEN_CREATE, NULL);
sqlite3_stmt* stm;
const char* pzTail;
int res;
res = sqlite3_prepare(db, "PRAGMA lic = '77523-009-0000007-72328';", -1, &stm, &pzTail); //software
license key
res = sqlite3_step(stm);
//now you have all access to regular data.db
res = sqlite3_prepare(db, "PRAGMA rekey = 'abc123';", -1, &stm, &pzTail);// encrypt database using abc123
passphrase
res = sqlite3_step(stm);
//now data.db is encrypted
Example 5: Using SQLiteCrypt command line tool
Opening encrypted db without passphrase:
D:\>sqlite.exe data.db
SQLite version 3.7.15.2 2013-01-09 11:53:05
Enter ".help" for instructions
Enter SQL statements terminated with a ";"
sqlite> select * from _MapPropertyA;
Error: file is encrypted or is not a database
Querry
on an encrypted database
SQLite version 3.7.15.2 2013-01-09 11:53:05
Enter ".help" for instructions
Enter SQL statements terminated with a ";"
sqlite> PRAGMA key = 'ac23';
sqlite> PRAGMA lic = '77523-009-0000007-72328';
sqlite> select * from _MapPropertyA;
3.0|8.0
3.0|8.0
