sqlcipher/README

103 lines
4.0 KiB
Plaintext

== SQLite Cipher ==
SQLite Cipher is an SQLite extension that provides transparent 256 bit AES encryption of database files.
Pages are encrypted before being written to disk and are decrypted when read back.
Encryption is provided by the OpenSSL crypto library.
SQLite Cipher was developed by Stephen Lombardo at Zetetic LLC.
sjlombardo at zetetic.net
http://zetetic.net
[Compiling]
Building SQLite Cipher is almost the same as compiling a regular version of SQLite with three small exceptions:
1. building via 'amalgamation' isn't supported (where all sqlite source is merged into one file)
2. you must define SQLITE_HAS_CODEC
3. You need to link against a OpenSSL's libcrypto with sha256 support compiled in
Example Static linking (replace /opt/local/lib with the path to libcrypto.a)
./configure --disable-amalgamation CFLAGS="-DSQLITE_HAS_CODEC" LDFLAGS="/opt/local/lib/libcrypto.a"
make
Example Dynamic linking
./configure --disable-amalgamation CFLAGS="-DSQLITE_HAS_CODEC -lcrypto"
make
[Encrypting a database]
To specify an encryption passphrase for the database you can use a pragma. The passphrase
you enter is hashed using sha256 and the result is used as the encryption key for the
database.
PRAGMA key = 'passphrase';
Alternately, you can specify an exact byte sequence using a blob literal. If you
use this method it is your responsibility to ensure that the data you provide a
64 character hex string, which will be converted directly to 32 bytes (256 bits) of
key data.
PRAGMA key = "x'2DD29CA851E7B56E4697B0E1F08507293D761A05CE4D1B628663F411A8086D99'";
To encrypt a database programatically you can use the sqlite3_key function. The data provided
in pKey is converted to an encryption key according to the same rules as PRAGMA key.
int sqlite3_key(sqlite3 *db, const void *pKey, int nKey);
PRAGMA key or sqlite3_key should be called as the first operation when a database is open.
Note: It is not currently possible to change the encryption key once a database is created. We're
working on implementing rekey functionality.
[License]
This code is released under the same public domain terms as SQLite itself.
THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.
== End SQLite Cipher ==
This directory contains source code to
SQLite: An Embeddable SQL Database Engine
To compile the project, first create a directory in which to place
the build products. It is recommended, but not required, that the
build directory be separate from the source directory. Cd into the
build directory and then from the build directory run the configure
script found at the root of the source tree. Then run "make".
For example:
tar xzf sqlite.tar.gz ;# Unpack the source tree into "sqlite"
mkdir bld ;# Build will occur in a sibling directory
cd bld ;# Change to the build directory
../sqlite/configure ;# Run the configure script
make ;# Run the makefile.
make install ;# (Optional) Install the build products
The configure script uses autoconf 2.61 and libtool. If the configure
script does not work out for you, there is a generic makefile named
"Makefile.linux-gcc" in the top directory of the source tree that you
can copy and edit to suit your needs. Comments on the generic makefile
show what changes are needed.
The linux binaries on the website are created using the generic makefile,
not the configure script.
The windows binaries on the website are created using MinGW32 configured
as a cross-compiler running under Linux. For details, see the ./publish.sh
script at the top-level of the source tree.
Contacts:
http://www.sqlite.org/