Original thread:

How to encrypt a previous sqlite database? davidmartos96/sqflite_sqlcipher#20

I have followed all the instructions from this video: https://www.youtube.com/watch?v=SFHGeetZ0po

Setp 1

Clone the source code from sqlite cipher: git clone https://github.com/sqlcipher/sqlcipher.git

Step 2

Download the Active TCL from: https://www.activestate.com/products/tcl/downloads/

Step 3

Download Windows Open SSL from https://slproweb.com/products/Win32OpenSSL.html Win64 OpenSSL v1.1.1g EXE

Setp 4

Edit the Makefile.smc from sqlcipher repository that was cloned: Change TCC = $(TCC) -DSQLITE_TEMP_STORE=1 to TCC = $(TCC) -DSQLITE_TEMP_STORE=2 -DSQLITE_HAS_CODEC -I"C:\Program Files\OpenSSL-Win64\include"

Search for LTLIBS = $(LTLIBS) $(LIBICU) and insert atfer the tag "# <</mark>>" the code:

LTLIBPATHS = $(LTLIBPATHS) /LIBPATH:"C:\Program Files\OpenSSL-Win64\lib\VC\static"
LTLIBS = $(LTLIBS) libcrypto64MT.lib libssl64MT.lib ws2_32.lib shell32.lib advapi32.lib gdi32.lib user32.lib crypt32.lib

Step 5

Open x64 Native Tools Command Prompt from Vs 2019 (Start menu / Visual Studio 2019); Navigate to where you clone the sqlcipher repository. In my case: cd C:\Repositorios\sqlitecipher Then compile the file Makefile typing the command: nmake /f Makefile.msc

Step 6 (if you got an error on Step 5)

When I try to compile on Windows 10 using x64 Native Tools Command Prompt from Vs 2019 (nmake /f Makefile.msc) , I've got an error of missing stdio.h.

So I had to download the Wnidows 10 SDK usign Visual Studio Installer. Close the console and open it again after installation finishes. Then try to compile again.

Step 7: Verify

After finish the compilation, it will be generated an 'sqlite3.exe' file inside the folder. On the same command prompt, run 'sqlite3.exe' and see if the message "SQLCipher Version XXXXX Connected to in memory transient database" appears.

Step 8:

After compilation, I added the path of sqlite3.exe to PATH environment system PATH.

Step 9: Bash Script

Then I made a separeted folder with my orignial sqlite database unencripted, and used this bash script from @davidmartos96 to convert the original database into a encrypted one.

#!/bin/bash
if [ -z "$1" ]
  then
    echo "No argument supplied"
    exit
fi 

echo "Encrypting $1" 
echo "ATTACH DATABASE 'encrypted.db' AS encrypted KEY '123456ABC'; SELECT sqlcipher_export('encrypted'); DETACH DATABASE encrypted;" | sqlite3 $1

echo
echo "Copying to Flutter project"
#rm C:/app_mobile/assets/databases/original_database.db

cp encrypted.db C:/app_mobile/assets/databases/original_database.db
#rm original_database.db

echo "Done."

I saved this code into a file called "bash_build.sh".

Step 10: Convert the database

I put a copy of the original database on the same folder as bash_build.sh. Make sure you have a backup of your database file because this file is deleted after encrypted.

Then, I used Git Bash (inside the same folder where bash_build.sh is located) to run the bash script: ./bash_build.sh myDatabase.db

Conclusion

I'm not expert on bash script or encryption, but I got this working with some help. I've tested the encripted file on Android Emulator and iPhone Simulator , and a Android physical devices using Flutter and sqflite_sqlcipher package, and works fine. If I pass a wrong password or don't pass any password at all, my app is not able to read the database. It only read the data when I pass the correct key.

If you want to open your encrypted sqlite file on Windows, download a version of SQLiteBrowser https://github.com/sqlitebrowser/sqlitebrowser/releases.

Also some usefull link (also posted on original thread): https://discuss.zetetic.net/t/how-to-encrypt-a-plaintext-sqlite-database-to-use-sqlcipher-and-avoid-file-is-encrypted-or-is-not-a-database-errors/868

This repository has all files that was used: bash script and all compiled sqlitecipher, so you can just use it directly as you want. They helped me, so I hope this helps you.