File : core/lib/DataEncryptor.js

/*
Copyright - 2017 2023 - wwwouaiebe - Contact: https://www.ouaie.be/

This  program is free software;
you can redistribute it and/or modify it under the terms of the
GNU General Public License as published by the Free Software Foundation;
either version 3 of the License, or any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; if not, write to the Free Software
Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
*/
/*
Changes:
    - v4.0.0:
        - created from v3.6.0
Doc reviewed 202208
 */

/* ------------------------------------------------------------------------------------------------------------------------- */
/**
This class is used to encrypt an decrypt data with a password
*/
/* ------------------------------------------------------------------------------------------------------------------------- */

class DataEncryptor {

    /**
    Salt to be used for encoding and decoding operations.
    @type {String}
    */

    #salt;

    /* eslint-disable no-magic-numbers */

    /**
    Call the importKey() method of the SubtleCrypto interface
    @param {Uint8Array} pswd The password to use, encode with TextEncoder.encode ( )
    @return {Promise} a Promise that fulfills with the imported key as a CryptoKey object
    */

    #importKey ( pswd ) {
        return window.crypto.subtle.importKey (
            'raw',
            pswd,
            { name : 'PBKDF2' },
            false,
            [ 'deriveKey' ]
        );
    }

    /**
    Call the deriveKey() method of the SubtleCrypto interface
    @param {CryptoKey} masterKey the CryptoKey returned by the onOk handler of the Promise returned by #importKey
    @param {String} salt The salt to use
    @return {Promise} a Promise which will be fulfilled with a CryptoKey object representing the secret key derived
    from the master key
    */

    #deriveKey ( masterKey, salt ) {
        return window.crypto.subtle.deriveKey (
            {
                name : 'PBKDF2',
                salt : new window.TextEncoder ( ).encode ( salt ),
                iterations : 1000000,
                hash : 'SHA-256'
            },
            masterKey,
            {
                name : 'AES-GCM',
                length : 256
            },
            false,
            [ 'encrypt', 'decrypt' ]
        );
    }

    /**
    Call the decrypt() method of the SubtleCrypto interface
    @param {CryptoKey} decryptKey The key to use for decryption
    @param {Uint8Array} data The data to decode
    @return {Promise} a Promise which will be fulfilled with the decrypted data as a Uint8Array.
    Use TextDecoder.decode ( ) to transform to string
    */

    #decrypt ( decryptKey, data ) {
        return window.crypto.subtle.decrypt (
            {
                name : 'AES-GCM',
                iv : new Uint8Array ( data.slice ( 0, 16 ) )
            },
            decryptKey,
            new Uint8Array ( data.slice ( 16 ) )
        );
    }

    /**
    Call the encrypt() method of the SubtleCrypto interface
    @param {CryptoKey} encryptKey The key to use for encryption
    @param {Uint8Array} ivBytes A Uint8Array with random values used for encoding
    @param {Uint8Array} data the data to encode transformed to a Uint8Array with TextEncoder.encode ( )
    @return {Promise} a Promise which will be fulfilled with the encrypted data as a Uint8Array
    */

    #encrypt ( encryptKey, ivBytes, data ) {
        return window.crypto.subtle.encrypt (
            {
                name : 'AES-GCM',
                iv : ivBytes
            },
            encryptKey,
            data
        );
    }

    /**
    The constructor
    @param {String} salt Salt to be used for encoding and decoding operations. If none, a default value is provided.
    */

    constructor ( salt ) {
        this.#salt = salt || 'Tire la chevillette la bobinette cherra. Le Petit Chaperon rouge tira la chevillette.';
        Object.freeze ( this );
    }

    /* eslint-disable max-params */

    /**
    This method encrypt data with a password
    @param {Uint8Array} data The data to encrypt. See TextEncoder ( ) to transform string to Uint8Array
    @param {function} onOk A function to execute when the encryption succeeds
    @param {function} onError A function to execute when the encryption fails
    @param {Promise} pswdPromise A Promise that fullfil with a password. Typically a dialog...
    */

    encryptData ( data, onOk, onError, pswdPromise ) {
        let ivBytes = window.crypto.getRandomValues ( new Uint8Array ( 16 ) );
        pswdPromise
            .then ( pswd => this.#importKey ( pswd ) )
            .then ( deriveKey => this.#deriveKey ( deriveKey, this.#salt ) )
            .then ( encryptKey => this.#encrypt ( encryptKey, ivBytes, data ) )
            .then (
                cipherText => {
                    onOk (
                        new Blob (
                            [ ivBytes, new Uint8Array ( cipherText ) ],
                            { type : 'application/octet-stream' }
                        )
                    );
                }
            )
            .catch ( onError );
    }

    /**
    This method decrypt data with a password
    @param {Uint8Array} data The data to decrypt. See TextDecoder ( ) to transform Uint8Array to string
    @param {function} onOk A function to execute when the decryption succeeds
    @param {function} onError A function to execute when the decryption fails
    @param {Promise} pswdPromise A Promise that fullfil with a password. Typically a dialog...
    */

    decryptData ( data, onOk, onError, pswdPromise ) {
        pswdPromise
            .then ( pswd => this.#importKey ( pswd ) )
            .then ( deriveKey => this.#deriveKey ( deriveKey, this.#salt ) )
            .then ( decryptKey => this.#decrypt ( decryptKey, data ) )
            .then ( onOk )
            .catch ( onError );
    }
    /* eslint-enable max-params */
    /* eslint-enable no-magic-numbers */
}

export default DataEncryptor;

/* --- End of file --------------------------------------------------------------------------------------------------------- */


1	/*
2	Copyright - 2017 2023 - wwwouaiebe - Contact: https://www.ouaie.be/
3
4	This program is free software;
5	you can redistribute it and/or modify it under the terms of the
6	GNU General Public License as published by the Free Software Foundation;
7	either version 3 of the License, or any later version.
8	This program is distributed in the hope that it will be useful,
9	but WITHOUT ANY WARRANTY; without even the implied warranty of
10	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
11	GNU General Public License for more details.
12	You should have received a copy of the GNU General Public License
13	along with this program; if not, write to the Free Software
14	Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
15	*/
16	/*
17	Changes:
18	- v4.0.0:
19	- created from v3.6.0
20	Doc reviewed 202208
21	*/
22
23	/* ------------------------------------------------------------------------------------------------------------------------- */
24	/**
25	This class is used to encrypt an decrypt data with a password
26	*/
27	/* ------------------------------------------------------------------------------------------------------------------------- */
28
29	class DataEncryptor {
30
31	/**
32	Salt to be used for encoding and decoding operations.
33	@type {String}
34	*/
35
36	#salt;
37
38	/* eslint-disable no-magic-numbers */
39
40	/**
41	Call the importKey() method of the SubtleCrypto interface
42	@param {Uint8Array} pswd The password to use, encode with TextEncoder.encode ( )
43	@return {Promise} a Promise that fulfills with the imported key as a CryptoKey object
44	*/
45
46	#importKey ( pswd ) {
47	return window.crypto.subtle.importKey (
48	'raw',
49	pswd,
50	{ name : 'PBKDF2' },
51	false,
52	[ 'deriveKey' ]
53	);
54	}
55
56	/**
57	Call the deriveKey() method of the SubtleCrypto interface
58	@param {CryptoKey} masterKey the CryptoKey returned by the onOk handler of the Promise returned by #importKey
59	@param {String} salt The salt to use
60	@return {Promise} a Promise which will be fulfilled with a CryptoKey object representing the secret key derived
61	from the master key
62	*/
63
64	#deriveKey ( masterKey, salt ) {
65	return window.crypto.subtle.deriveKey (
66	{
67	name : 'PBKDF2',
68	salt : new window.TextEncoder ( ).encode ( salt ),
69	iterations : 1000000,
70	hash : 'SHA-256'
71	},
72	masterKey,
73	{
74	name : 'AES-GCM',
75	length : 256
76	},
77	false,
78	[ 'encrypt', 'decrypt' ]
79	);
80	}
81
82	/**
83	Call the decrypt() method of the SubtleCrypto interface
84	@param {CryptoKey} decryptKey The key to use for decryption
85	@param {Uint8Array} data The data to decode
86	@return {Promise} a Promise which will be fulfilled with the decrypted data as a Uint8Array.
87	Use TextDecoder.decode ( ) to transform to string
88	*/
89
90	#decrypt ( decryptKey, data ) {
91	return window.crypto.subtle.decrypt (
92	{
93	name : 'AES-GCM',
94	iv : new Uint8Array ( data.slice ( 0, 16 ) )
95	},
96	decryptKey,
97	new Uint8Array ( data.slice ( 16 ) )
98	);
99	}
100
101	/**
102	Call the encrypt() method of the SubtleCrypto interface
103	@param {CryptoKey} encryptKey The key to use for encryption
104	@param {Uint8Array} ivBytes A Uint8Array with random values used for encoding
105	@param {Uint8Array} data the data to encode transformed to a Uint8Array with TextEncoder.encode ( )
106	@return {Promise} a Promise which will be fulfilled with the encrypted data as a Uint8Array
107	*/
108
109	#encrypt ( encryptKey, ivBytes, data ) {
110	return window.crypto.subtle.encrypt (
111	{
112	name : 'AES-GCM',
113	iv : ivBytes
114	},
115	encryptKey,
116	data
117	);
118	}
119
120	/**
121	The constructor
122	@param {String} salt Salt to be used for encoding and decoding operations. If none, a default value is provided.
123	*/
124
125	constructor ( salt ) {
126	this.#salt = salt \|\| 'Tire la chevillette la bobinette cherra. Le Petit Chaperon rouge tira la chevillette.';
127	Object.freeze ( this );
128	}
129
130	/* eslint-disable max-params */
131
132	/**
133	This method encrypt data with a password
134	@param {Uint8Array} data The data to encrypt. See TextEncoder ( ) to transform string to Uint8Array
135	@param {function} onOk A function to execute when the encryption succeeds
136	@param {function} onError A function to execute when the encryption fails
137	@param {Promise} pswdPromise A Promise that fullfil with a password. Typically a dialog...
138	*/
139
140	encryptData ( data, onOk, onError, pswdPromise ) {
141	let ivBytes = window.crypto.getRandomValues ( new Uint8Array ( 16 ) );
142	pswdPromise
143	.then ( pswd => this.#importKey ( pswd ) )
144	.then ( deriveKey => this.#deriveKey ( deriveKey, this.#salt ) )
145	.then ( encryptKey => this.#encrypt ( encryptKey, ivBytes, data ) )
146	.then (
147	cipherText => {
148	onOk (
149	new Blob (
150	[ ivBytes, new Uint8Array ( cipherText ) ],
151	{ type : 'application/octet-stream' }
152	)
153	);
154	}
155	)
156	.catch ( onError );
157	}
158
159	/**
160	This method decrypt data with a password
161	@param {Uint8Array} data The data to decrypt. See TextDecoder ( ) to transform Uint8Array to string
162	@param {function} onOk A function to execute when the decryption succeeds
163	@param {function} onError A function to execute when the decryption fails
164	@param {Promise} pswdPromise A Promise that fullfil with a password. Typically a dialog...
165	*/
166
167	decryptData ( data, onOk, onError, pswdPromise ) {
168	pswdPromise
169	.then ( pswd => this.#importKey ( pswd ) )
170	.then ( deriveKey => this.#deriveKey ( deriveKey, this.#salt ) )
171	.then ( decryptKey => this.#decrypt ( decryptKey, data ) )
172	.then ( onOk )
173	.catch ( onError );
174	}
175	/* eslint-enable max-params */
176	/* eslint-enable no-magic-numbers */
177	}
178
179	export default DataEncryptor;
180
181	/* --- End of file --------------------------------------------------------------------------------------------------------- */
182