wallet-core: implement basic wallet KYC for balance thresholds

1 files changed, 63 insertions, 0 deletions

diff --git a/packages/taler-util/src/taler-signatures.ts b/packages/taler-util/src/taler-signatures.ts
new file mode 100644
index 000000000..81b7c242e
--- /dev/null
+++ b/packages/taler-util/src/taler-signatures.ts
@@ -0,0 +1,63 @@
+/*
+ This file is part of GNU Taler
+ (C) 2024 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 { canonicalJson } from "./index.js";
+import {
+  bufferForUint64,
+  buildSigPS,
+  decodeCrock,
+  eddsaSign,
+  hash,
+  stringToBytes,
+  TalerSignaturePurpose,
+  timestampRoundedToBuffer,
+} from "./taler-crypto.js";
+import { AmlDecisionRequestWithoutSignature } from "./types-taler-exchange.js";
+
+/**
+ * Implementation of Taler protocol signatures.
+ *
+ * In this file, we have implementations of signatures that are not used in the wallet,
+ * but in other places (tests, SPAs, ...).
+ */
+
+/**
+ * Signature for the POST /aml/$OFFICER_PUB/decisions endpoint.
+ */
+export function signAmlDecision(
+  priv: Uint8Array,
+  decision: AmlDecisionRequestWithoutSignature,
+): Uint8Array {
+  const builder = buildSigPS(TalerSignaturePurpose.AML_DECISION);
+
+  const flags: number = decision.keep_investigating ? 1 : 0;
+
+  builder.put(timestampRoundedToBuffer(decision.decision_time));
+  builder.put(decodeCrock(decision.h_payto));
+  builder.put(hash(stringToBytes(decision.justification)));
+  builder.put(hash(stringToBytes(canonicalJson(decision.properties) + "\0")));
+  builder.put(hash(stringToBytes(canonicalJson(decision.new_rules) + "\0")));
+  if (decision.new_measure != null) {
+    builder.put(hash(stringToBytes(decision.new_measure)));
+  } else {
+    builder.put(new Uint8Array(64));
+  }
+  builder.put(bufferForUint64(flags));
+
+  const sigBlob = builder.build();
+
+  return eddsaSign(sigBlob, priv);
+}