Implement signature

src/signature.ts

@@ -1,13 +1,51 @@
-export type PrivKey = void
-export type PubKey = void
-export type Signature = string
+import {Result} from 'result'
 
-export function gen_keypair() : [PrivKey, PubKey] {
-    throw "todo"
+export type PrivKey = CryptoKey
+export type PubKey = CryptoKey
+
+const algorithm: EcdsaParams = {
+    name: "ECDSA",
+    hash: {name: "SHA-512"},
 }
-export function sign(privkey: PrivKey, message: Uint8Array) : Signature {
-    throw "todo"
+
+/**
+ * Create a new keypair for signing
+ * @param extractable if the keys must be extractable or not
+ * @return [privkey, pubkey] keys
+ */
+export async function gen_keypair(extractable: boolean = false) : Promise<[PrivKey, PubKey]> {
+    let key = await window.crypto.subtle.generateKey(
+        {
+            name: "ECDSA",
+            namedCurve: "P-521"
+        } as EcKeyGenParams,
+        extractable,
+        ['sign', 'verify']
+    )
+
+    return [key.privateKey, key.publicKey]
 }
-export function verify(pubkey: PubKey, message: Uint8Array, signature: Signature) : boolean {
-    throw "todo"
+export async function sign(privkey: PrivKey, message: Uint8Array) : Promise<Result<ArrayBuffer>> {
+    try {
+        return Result.ok(await window.crypto.subtle.sign(
+            algorithm,
+            privkey,
+            message,
+        ))
+    } catch(_) {}
+
+    return Result.error([])
+}
+
+export async function verify(pubkey: PubKey, message: Uint8Array, signature: ArrayBuffer): Promise<boolean> {
+    try {
+        return await window.crypto.subtle.verify(
+            algorithm,
+            pubkey,
+            signature,
+            message
+        );
+    } catch (_) {}
+
+    return false;
 }