From 4d2cf85a5185b7f64beeabf69349a2f7e13b9bd9 Mon Sep 17 00:00:00 2001
From: Celine Moredo <32130856+camoredo@users.noreply.github.com>
Date: Mon, 22 Aug 2022 21:30:33 +0800
Subject: [PATCH] Ignore improperly formatted armor headers (#1557)

Show a debug warning instead of throwing an error on malformed headers.
---
 src/encoding/armor.js |  8 +++++---
 test/general/armor.js | 15 ++++-----------
 2 files changed, 9 insertions(+), 14 deletions(-)

diff --git a/src/encoding/armor.js b/src/encoding/armor.js
index 99c0d282..6f402546 100644
--- a/src/encoding/armor.js
+++ b/src/encoding/armor.js
@@ -182,15 +182,17 @@ function createcrc24(input) {
 }
 
 /**
- * Verify armored headers. RFC4880, section 6.3: "OpenPGP should consider improperly formatted
- * Armor Headers to be corruption of the ASCII Armor."
+ * Verify armored headers. crypto-refresh-06, section 6.2:
+ * "An OpenPGP implementation may consider improperly formatted Armor
+ * Headers to be corruption of the ASCII Armor, but SHOULD make an
+ * effort to recover."
  * @private
  * @param {Array<String>} headers - Armor headers
  */
 function verifyHeaders(headers) {
   for (let i = 0; i < headers.length; i++) {
     if (!/^([^\s:]|[^\s:][^:]*[^\s:]): .+$/.test(headers[i])) {
-      throw new Error('Improperly formatted armor header: ' + headers[i]);
+      util.printDebugError(new Error('Improperly formatted armor header: ' + headers[i]));
     }
     if (!/^(Version|Comment|MessageID|Hash|Charset): .+$/.test(headers[i])) {
       util.printDebugError(new Error('Unknown header: ' + headers[i]));
diff --git a/test/general/armor.js b/test/general/armor.js
index c7958546..1611fcd1 100644
--- a/test/general/armor.js
+++ b/test/general/armor.js
@@ -101,21 +101,14 @@ module.exports = () => describe('ASCII armor', function() {
     expect(msg).to.be.an.instanceof(openpgp.CleartextMessage);
   });
 
-  it('Exception if improperly formatted armor header - plaintext section', async function () {
-    let msg = getArmor(['Hash:SHA256']);
-    msg = openpgp.readCleartextMessage({ cleartextMessage: msg });
-    await expect(msg).to.be.rejectedWith(Error, /Improperly formatted armor header/);
-    msg = getArmor(['Ha sh: SHA256']);
-    msg = openpgp.readCleartextMessage({ cleartextMessage: msg });
+  it('Exception if header is not Hash in cleartext signed message', async function () {
+    const msg = openpgp.readCleartextMessage({ cleartextMessage: getArmor(['Ha sh: SHA256']) });
     await expect(msg).to.be.rejectedWith(Error, /Only "Hash" header allowed in cleartext signed message/);
-    msg = getArmor(['Hash SHA256']);
-    msg = openpgp.readCleartextMessage({ cleartextMessage: msg });
-    await expect(msg).to.be.rejectedWith(Error, /Improperly formatted armor header/);
   });
 
-  it('Exception if improperly formatted armor header - signature section', async function () {
+  it('Ignore improperly formatted armor header', async function () {
     await Promise.all(['Space : trailing', 'Space :switched', ': empty', 'none', 'Space:missing'].map(async function (invalidHeader) {
-      await expect(openpgp.readCleartextMessage({ cleartextMessage: getArmor(['Hash: SHA1'], [invalidHeader]) })).to.be.rejectedWith(Error, /Improperly formatted armor header/);
+      expect(await openpgp.readCleartextMessage({ cleartextMessage: getArmor(['Hash: SHA1'], [invalidHeader]) })).to.be.an.instanceof(openpgp.CleartextMessage);
     }));
   });