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node_modules/matrix-js-sdk/lib/crypto-api/key-passphrase.js

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+/*
+ * Copyright 2024 The Matrix.org Foundation C.I.C.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+const DEFAULT_BIT_SIZE = 256;
+
+/**
+ * Derive a recovery key from a passphrase and salt using PBKDF2.
+ * @see https://spec.matrix.org/v1.11/client-server-api/#deriving-keys-from-passphrases
+ *
+ * @param passphrase - The passphrase to derive the key from
+ * @param salt - The salt to use in the derivation
+ * @param iterations - The number of iterations to use in the derivation
+ * @param numBits - The number of bits to derive
+ */
+export async function deriveRecoveryKeyFromPassphrase(passphrase, salt, iterations, numBits = DEFAULT_BIT_SIZE) {
+  if (!globalThis.crypto.subtle || !TextEncoder) {
+    throw new Error("Password-based backup is not available on this platform");
+  }
+  const key = await globalThis.crypto.subtle.importKey("raw", new TextEncoder().encode(passphrase), {
+    name: "PBKDF2"
+  }, false, ["deriveBits"]);
+  const keybits = await globalThis.crypto.subtle.deriveBits({
+    name: "PBKDF2",
+    salt: new TextEncoder().encode(salt),
+    iterations: iterations,
+    hash: "SHA-512"
+  }, key, numBits);
+  return new Uint8Array(keybits);
+}
+//# sourceMappingURL=key-passphrase.js.map