1 files changed, 38 insertions, 0 deletions
diff --git a/web/js/browser/lib/recoveryKey.js b/web/js/browser/lib/recoveryKey.js
new file mode 100644
index 0000000..cc8604d
--- /dev/null
+++ b/web/js/browser/lib/recoveryKey.js
@@ -0,0 +1,38 @@
+var __awaiter = (this && this.__awaiter) || function (thisArg, _arguments, P, generator) {
+    function adopt(value) { return value instanceof P ? value : new P(function (resolve) { resolve(value); }); }
+    return new (P || (P = Promise))(function (resolve, reject) {
+        function fulfilled(value) { try { step(generator.next(value)); } catch (e) { reject(e); } }
+        function rejected(value) { try { step(generator["throw"](value)); } catch (e) { reject(e); } }
+        function step(result) { result.done ? resolve(result.value) : adopt(result.value).then(fulfilled, rejected); }
+        step((generator = generator.apply(thisArg, _arguments || [])).next());
+    });
+};
+import { jweEncrypt, hkdf } from './crypto';
+import { hexToUint8, uint8ToHex } from './utils';
+function randomKey() {
+    return __awaiter(this, void 0, void 0, function* () {
+        // The key is displayed in base32 'Crockford' so the length should be
+        // divisible by (5 bits per character) and (8 bits per byte).
+        // 20 bytes == 160 bits == 32 base32 characters
+        const recoveryKey = yield crypto.getRandomValues(new Uint8Array(20));
+        // Flip bits to set first char to base32 'A' as a version identifier.
+        // Why 'A'? https://github.com/mozilla/fxa-content-server/pull/6323#discussion_r201211711
+        recoveryKey[0] = 0x50 | (0x07 & recoveryKey[0]);
+        return recoveryKey;
+    });
+}
+export function generateRecoveryKey(uid, keys, forTestingOnly) {
+    return __awaiter(this, void 0, void 0, function* () {
+        const recoveryKey = (forTestingOnly === null || forTestingOnly === void 0 ? void 0 : forTestingOnly.testRecoveryKey) || (yield randomKey());
+        const encoder = new TextEncoder();
+        const salt = hexToUint8(uid);
+        const encryptionKey = yield hkdf(recoveryKey, salt, encoder.encode('fxa recovery encrypt key'), 32);
+        const recoveryKeyId = uint8ToHex(yield hkdf(recoveryKey, salt, encoder.encode('fxa recovery fingerprint'), 16));
+        const recoveryData = yield jweEncrypt(encryptionKey, recoveryKeyId, encoder.encode(JSON.stringify(keys)), forTestingOnly ? { testIV: forTestingOnly.testIV } : undefined);
+        return {
+            recoveryKey,
+            recoveryKeyId,
+            recoveryData,
+        };
+    });
+}