@@ -14,153 +14,13 @@ See the License for the specific language governing permissions and
1414limitations under the License.
1515*/
1616
17- import { decodeBase64 , encodeBase64 } from "../base64.ts" ;
18-
19- // salt for HKDF, with 8 bytes of zeros
20- const zeroSalt = new Uint8Array ( 8 ) ;
21-
22- export interface IEncryptedPayload {
23- [ key : string ] : any ; // extensible
24- /** the initialization vector in base64 */
25- iv : string ;
26- /** the ciphertext in base64 */
27- ciphertext : string ;
28- /** the HMAC in base64 */
29- mac : string ;
30- }
31-
32- /**
33- * Encrypt a string using AES-CTR.
34- *
35- * @param data - the plaintext to encrypt
36- * @param key - the encryption key to use as an input to the HKDF function which is used to derive the AES key for
37- * encryption. Obviously, the same key must be provided when decrypting.
38- * @param name - the name of the secret. Used as an input to the HKDF operation which is used to derive the AES key,
39- * so again the same value must be provided when decrypting.
40- * @param ivStr - the base64-encoded initialization vector to use. If not supplied, a random one will be generated.
41- *
42- * @returns The encrypted result, including the ciphertext itself, the initialization vector (as supplied in `ivStr`,
43- * or generated), and an HMAC on the ciphertext — all base64-encoded.
44- */
45- export async function encryptAES (
46- data : string ,
47- key : Uint8Array ,
48- name : string ,
49- ivStr ?: string ,
50- ) : Promise < IEncryptedPayload > {
51- let iv : Uint8Array ;
52- if ( ivStr ) {
53- iv = decodeBase64 ( ivStr ) ;
54- } else {
55- iv = new Uint8Array ( 16 ) ;
56- globalThis . crypto . getRandomValues ( iv ) ;
57-
58- // clear bit 63 of the IV to stop us hitting the 64-bit counter boundary
59- // (which would mean we wouldn't be able to decrypt on Android). The loss
60- // of a single bit of iv is a price we have to pay.
61- iv [ 8 ] &= 0x7f ;
62- }
63-
64- const [ aesKey , hmacKey ] = await deriveKeys ( key , name ) ;
65- const encodedData = new TextEncoder ( ) . encode ( data ) ;
66-
67- const ciphertext = await globalThis . crypto . subtle . encrypt (
68- {
69- name : "AES-CTR" ,
70- counter : iv ,
71- length : 64 ,
72- } ,
73- aesKey ,
74- encodedData ,
75- ) ;
76-
77- const hmac = await globalThis . crypto . subtle . sign ( { name : "HMAC" } , hmacKey , ciphertext ) ;
78-
79- return {
80- iv : encodeBase64 ( iv ) ,
81- ciphertext : encodeBase64 ( ciphertext ) ,
82- mac : encodeBase64 ( hmac ) ,
83- } ;
84- }
85-
86- /**
87- * Decrypt an AES-encrypted string.
88- *
89- * @param data - the encrypted data, returned by {@link encryptAES}.
90- * @param key - the encryption key to use as an input to the HKDF function which is used to derive the AES key. Must
91- * be the same as provided to {@link encryptAES}.
92- * @param name - the name of the secret. Also used as an input to the HKDF operation which is used to derive the AES
93- * key, so again must be the same as provided to {@link encryptAES}.
94- */
95- export async function decryptAES ( data : IEncryptedPayload , key : Uint8Array , name : string ) : Promise < string > {
96- const [ aesKey , hmacKey ] = await deriveKeys ( key , name ) ;
97-
98- const ciphertext = decodeBase64 ( data . ciphertext ) ;
99-
100- if ( ! ( await globalThis . crypto . subtle . verify ( { name : "HMAC" } , hmacKey , decodeBase64 ( data . mac ) , ciphertext ) ) ) {
101- throw new Error ( `Error decrypting secret ${ name } ) ;
102- }
103-
104- const plaintext = await globalThis . crypto . subtle . decrypt (
105- {
106- name : "AES-CTR" ,
107- counter : decodeBase64 ( data . iv ) ,
108- length : 64 ,
109- } ,
110- aesKey ,
111- ciphertext ,
112- ) ;
113-
114- return new TextDecoder ( ) . decode ( new Uint8Array ( plaintext ) ) ;
115- }
116-
117- async function deriveKeys ( key : Uint8Array , name : string ) : Promise < [ CryptoKey , CryptoKey ] > {
118- const hkdfkey = await globalThis . crypto . subtle . importKey ( "raw" , key , { name : "HKDF" } , false , [ "deriveBits" ] ) ;
119- const keybits = await globalThis . crypto . subtle . deriveBits (
120- {
121- name : "HKDF" ,
122- salt : zeroSalt ,
123- // eslint-disable-next-line @typescript-eslint/ban-ts-comment
124- // @ts -ignore: https://github.com/microsoft/TypeScript-DOM-lib-generator/pull/879
125- info : new TextEncoder ( ) . encode ( name ) ,
126- hash : "SHA-256" ,
127- } ,
128- hkdfkey ,
129- 512 ,
130- ) ;
131-
132- const aesKey = keybits . slice ( 0 , 32 ) ;
133- const hmacKey = keybits . slice ( 32 ) ;
134-
135- const aesProm = globalThis . crypto . subtle . importKey ( "raw" , aesKey , { name : "AES-CTR" } , false , [
136- "encrypt" ,
137- "decrypt" ,
138- ] ) ;
139-
140- const hmacProm = globalThis . crypto . subtle . importKey (
141- "raw" ,
142- hmacKey ,
143- {
144- name : "HMAC" ,
145- hash : { name : "SHA-256" } ,
146- } ,
147- false ,
148- [ "sign" , "verify" ] ,
149- ) ;
150-
151- return Promise . all ( [ aesProm , hmacProm ] ) ;
152- }
153-
154- // string of zeroes, for calculating the key check
155- const ZERO_STR = "\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0\0" ;
156-
157- /** Calculate the MAC for checking the key.
158- *
159- * @param key - the key to use
160- * @param iv - The initialization vector as a base64-encoded string.
161- * If omitted, a random initialization vector will be created.
162- * @returns An object that contains, `mac` and `iv` properties.
163- */
164- export function calculateKeyCheck ( key : Uint8Array , iv ?: string ) : Promise < IEncryptedPayload > {
165- return encryptAES ( ZERO_STR , key , "" , iv ) ;
166- }
17+ import encryptAESSecretStorageItem from "../utils/encryptAESSecretStorageItem.ts" ;
18+ import decryptAESSecretStorageItem from "../utils/decryptAESSecretStorageItem.ts" ;
19+ import { AESEncryptedSecretStoragePayload } from "../@types/AESEncryptedSecretStoragePayload.ts" ;
20+
21+ // Export for backwards compatibility
22+ export type { AESEncryptedSecretStoragePayload as IEncryptedPayload } ;
23+ // Export with new names instead of using `as` to not break react-sdk tests
24+ export const encryptAES = encryptAESSecretStorageItem ;
25+ export const decryptAES = decryptAESSecretStorageItem ;
26+ export { calculateKeyCheck } from "../calculateKeyCheck.ts" ;
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