support jwk keys to encrypt

src/matrix/e2ee/attachment.js

@@ -62,7 +62,7 @@ export async function encryptAttachment(platform, blob) {
     const iv = await crypto.aes.generateIV();
     const key = await crypto.aes.generateKey("jwk", 256);
     const buffer = await blob.readAsBuffer();
-    const ciphertext = await crypto.aes.encryptCTR({key, iv, data: buffer});
+    const ciphertext = await crypto.aes.encryptCTR({jwkKey: key, iv, data: buffer});
     const digest = await crypto.digest("SHA-256", ciphertext);
     return {
         blob: platform.createBlob(ciphertext, blob.mimeType),

src/platform/web/dom/Crypto.js

@@ -199,17 +199,19 @@ class AESCrypto {
         }
     }
 
-    async encryptCTR({key, iv, data}) {
+    async encryptCTR({key, jwkKey, iv, data}) {
         const opts = {
             name: "AES-CTR",
             counter: iv,
             length: 64,
         };
         let aesKey;
+        const selectedKey = key || jwkKey;
+        const format = jwkKey ? "jwk" : "raw";
         try {
             aesKey = await subtleCryptoResult(this._subtleCrypto.importKey(
-                "raw",
-                key,
+                format,
+                selectedKey,
                 opts,
                 false,
                 ['encrypt'],