From 3817cca3c619e7479137af1af998a99cd577923e Mon Sep 17 00:00:00 2001
From: Daniel Huigens <d.huigens@protonmail.com>
Date: Wed, 26 Feb 2020 16:22:57 +0100
Subject: [PATCH] Throw on unarmored messages with garbage data appended

---
 src/openpgp.js          | 15 +++++++++++++--
 src/packet/packet.js    | 10 +++-------
 test/general/openpgp.js |  9 +++++++++
 3 files changed, 25 insertions(+), 9 deletions(-)

diff --git a/src/openpgp.js b/src/openpgp.js
index 63961c99..a0a9a993 100644
--- a/src/openpgp.js
+++ b/src/openpgp.js
@@ -369,7 +369,7 @@ export function decrypt({ message, privateKeys, passwords, sessionKeys, publicKe
     result.signatures = signature ? await decrypted.verifyDetached(signature, publicKeys, date, streaming) : await decrypted.verify(publicKeys, date, streaming);
     result.data = format === 'binary' ? decrypted.getLiteralData() : decrypted.getText();
     result.filename = decrypted.getFilename();
-    if (streaming) linkStreams(result, message);
+    linkStreams(result, message);
     result.data = await convertStream(result.data, streaming, format);
     if (!streaming) await prepareSignatures(result.signatures);
     return result;
@@ -635,13 +635,24 @@ async function convertStream(data, streaming, encoding = 'utf8') {
 
 /**
  * Link result.data to the message stream for cancellation.
+ * Also, forward errors in the message to result.data.
  * @param  {Object} result                  the data to convert
  * @param  {Message} message                message object
  * @returns {Object}
  */
 function linkStreams(result, message) {
   result.data = stream.transformPair(message.packets.stream, async (readable, writable) => {
-    await stream.pipe(result.data, writable);
+    await stream.pipe(result.data, writable, {
+      preventClose: true
+    });
+    const writer = stream.getWriter(writable);
+    try {
+      // Forward errors in the message stream to result.data.
+      await stream.readToEnd(readable, _ => _);
+      await writer.close();
+    } catch (e) {
+      await writer.abort(e);
+    }
   });
 }
 
diff --git a/src/packet/packet.js b/src/packet/packet.js
index af399620..49b61b2f 100644
--- a/src/packet/packet.js
+++ b/src/packet/packet.js
@@ -249,13 +249,9 @@ export default {
       // entire remainder of the stream, in order to forward errors in the
       // remainder of the stream to the packet data. (Note that this means we
       // read/peek at all signature packets before closing the literal data
-      // packet, for example.) This forwards armor checksum errors to the
-      // encrypted data stream, for example, so that they don't get lost /
-      // forgotten on encryptedMessage.packets.stream, which we never look at.
-      //
-      // Note that subsequent packet parsing errors could still end up there if
-      // `config.tolerant` is set to false, or on malformed messages with
-      // multiple data packets, but usually it shouldn't happen.
+      // packet, for example.) This forwards MDC errors to the literal data
+      // stream, for example, so that they don't get lost / forgotten on
+      // decryptedMessage.packets.stream, which we never look at.
       //
       // An example of what we do when stream-parsing a message containing
       // [ one-pass signature packet, literal data packet, signature packet ]:
diff --git a/test/general/openpgp.js b/test/general/openpgp.js
index 3701a25c..3a316282 100644
--- a/test/general/openpgp.js
+++ b/test/general/openpgp.js
@@ -1700,6 +1700,15 @@ describe('OpenPGP.js public api tests', function() {
             }));
           }
         });
+
+        it('should fail to decrypt unarmored message with garbage data appended', async function() {
+          const { key } = await openpgp.generateKey({ userIds: {} });
+          const message = await openpgp.encrypt({ message: openpgp.message.fromText('test'), publicKeys: key, privateKeys: key, armor: false });
+          const encrypted = openpgp.util.concat([message, new Uint8Array([11])]);
+          await expect(
+            openpgp.decrypt({ message: await openpgp.message.read(encrypted), privateKeys: key, publicKeys: key })
+          ).to.be.rejectedWith('Error during parsing. This message / key probably does not conform to a valid OpenPGP format.');
+        });
       });
 
       describe('ELG / DSA encrypt, decrypt, sign, verify', function() {