feat: add crypto

lib/build-gutka.js

@@ -1,8 +1,10 @@
 require( './string-colors' )
 const GURMUKHI_SOURCES = require( '../data/sourcesList' )
 const build = require( './build-database' )
+const { encrypt } = require( './utils' )
 const { filename } = require( '..' )
 const fs = require( 'fs' )
+const prompts = require( 'prompts' )
 
 const OUTPUT_PATH = './build'
 const outputFile = `${OUTPUT_PATH}/gutka-db.sqlite`
@@ -88,6 +90,24 @@ const afterBuild = async knex => {
     table.dropColumn( 'visible' )
   } )
 
+  // Ecrypt data
+  const response = await prompts( {
+    type: 'password',
+    name: 'key',
+    message: 'Enter encryption key:',
+  } )
+  await knex.select().from( 'line_content' ).then( lines => {
+    console.log( 'Encrypting data...' )
+    lines.forEach( async line => {
+      await knex( 'line_content' )
+        .where( 'line_id', line.line_id )
+        .update( {
+          gurmukhi: encrypt( line.gurmukhi, response.key ),
+          larivaar: encrypt( line.larivaar, response.key ),
+        } )
+    } )
+  } )
+
   // Compact sqlite db
   await knex.raw( 'VACUUM' )
 

lib/utils.js

@@ -4,6 +4,7 @@
 
 const { anyid } = require( 'anyid' )
 const { basename } = require( 'path' )
+const crypto = require( 'crypto' )
 const { findBestMatch } = require( 'string-similarity' )
 const memoize = require( 'memoizee' )
 const { promisify } = require( 'util' )
@@ -82,6 +83,15 @@ const larivaar = input => input
   .replace( /\s+\u200B/ug, ' ' )
   .replace( /\u200B\s+/ug, ' ' )
 
+const encrypt = ( string, password ) => {
+  const passwordHash = crypto.createHash( 'sha256' ).update( password ).digest()
+  const iv = crypto.randomBytes( 16 )
+  const cipher = crypto.createCipheriv( 'aes-256-gcm', passwordHash, iv )
+  const encrypted = Buffer.concat( [ cipher.update( string, 'utf8' ), cipher.final() ] )
+  const tag = cipher.getAuthTag()
+  return Buffer.concat( [ iv, tag, encrypted ] ).toString( 'base64' )
+}
+
 module.exports = {
   writeJSON,
   stripExtension,
@@ -90,4 +100,5 @@ module.exports = {
   findIndex,
   fsCopy,
   larivaar,
+  encrypt,
 }