summaryrefslogtreecommitdiff
path: root/packages/taler-wallet-core/src/crypto/primitives/kdf.ts
diff options
context:
space:
mode:
authorFlorian Dold <florian.dold@gmail.com>2020-08-03 13:00:48 +0530
committerFlorian Dold <florian.dold@gmail.com>2020-08-03 13:01:05 +0530
commitffd2a62c3f7df94365980302fef3bc3376b48182 (patch)
tree270af6f16b4cc7f5da2afdba55c8bc9dbea5eca5 /packages/taler-wallet-core/src/crypto/primitives/kdf.ts
parentaa481e42675fb7c4dcbbeec0ba1c61e1953b9596 (diff)
downloadwallet-core-ffd2a62c3f7df94365980302fef3bc3376b48182.tar.gz
wallet-core-ffd2a62c3f7df94365980302fef3bc3376b48182.tar.bz2
wallet-core-ffd2a62c3f7df94365980302fef3bc3376b48182.zip
modularize repo, use pnpm, improve typechecking
Diffstat (limited to 'packages/taler-wallet-core/src/crypto/primitives/kdf.ts')
-rw-r--r--packages/taler-wallet-core/src/crypto/primitives/kdf.ts92
1 files changed, 92 insertions, 0 deletions
diff --git a/packages/taler-wallet-core/src/crypto/primitives/kdf.ts b/packages/taler-wallet-core/src/crypto/primitives/kdf.ts
new file mode 100644
index 000000000..edc681bc1
--- /dev/null
+++ b/packages/taler-wallet-core/src/crypto/primitives/kdf.ts
@@ -0,0 +1,92 @@
+/*
+ This file is part of GNU Taler
+ (C) 2019 GNUnet e.V.
+
+ GNU Taler 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, or (at your option) any later version.
+
+ GNU Taler 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
+ GNU Taler; see the file COPYING. If not, see <http://www.gnu.org/licenses/>
+ */
+
+import * as nacl from "./nacl-fast";
+import { sha256 } from "./sha256";
+
+export function sha512(data: Uint8Array): Uint8Array {
+ return nacl.hash(data);
+}
+
+export function hmac(
+ digest: (d: Uint8Array) => Uint8Array,
+ blockSize: number,
+ key: Uint8Array,
+ message: Uint8Array,
+): Uint8Array {
+ if (key.byteLength > blockSize) {
+ key = digest(key);
+ }
+ if (key.byteLength < blockSize) {
+ const k = key;
+ key = new Uint8Array(blockSize);
+ key.set(k, 0);
+ }
+ const okp = new Uint8Array(blockSize);
+ const ikp = new Uint8Array(blockSize);
+ for (let i = 0; i < blockSize; i++) {
+ ikp[i] = key[i] ^ 0x36;
+ okp[i] = key[i] ^ 0x5c;
+ }
+ const b1 = new Uint8Array(blockSize + message.byteLength);
+ b1.set(ikp, 0);
+ b1.set(message, blockSize);
+ const h0 = digest(b1);
+ const b2 = new Uint8Array(blockSize + h0.length);
+ b2.set(okp, 0);
+ b2.set(h0, blockSize);
+ return digest(b2);
+}
+
+export function hmacSha512(key: Uint8Array, message: Uint8Array): Uint8Array {
+ return hmac(sha512, 128, key, message);
+}
+
+export function hmacSha256(key: Uint8Array, message: Uint8Array): Uint8Array {
+ return hmac(sha256, 64, key, message);
+}
+
+export function kdf(
+ outputLength: number,
+ ikm: Uint8Array,
+ salt: Uint8Array,
+ info: Uint8Array,
+): Uint8Array {
+ // extract
+ const prk = hmacSha512(salt, ikm);
+
+ // expand
+ const N = Math.ceil(outputLength / 32);
+ const output = new Uint8Array(N * 32);
+ for (let i = 0; i < N; i++) {
+ let buf;
+ if (i == 0) {
+ buf = new Uint8Array(info.byteLength + 1);
+ buf.set(info, 0);
+ } else {
+ buf = new Uint8Array(info.byteLength + 1 + 32);
+ for (let j = 0; j < 32; j++) {
+ buf[j] = output[(i - 1) * 32 + j];
+ }
+ buf.set(info, 32);
+ }
+ buf[buf.length - 1] = i + 1;
+ const chunk = hmacSha256(prk, buf);
+ output.set(chunk, i * 32);
+ }
+
+ return output.slice(0, outputLength);
+}