From 8db94be8acbd3c0a40a92e14f0696f6ca1af957d Mon Sep 17 00:00:00 2001
From: toby <tlornewr@gmail.com>
Date: Wed, 15 Mar 2017 12:06:32 -0400
Subject: [PATCH] Add operation "Detach PGP Cleartext"

This operation is like "Remove PGP ASCII Armor" but for detached
signatures. It outputs files as HTML similar to "Sign PGP Detached".
---
 src/js/config/OperationConfig.js |  8 +++++
 src/js/operations/PGP.js         | 56 ++++++++++++++++++++++++++++++++
 2 files changed, 64 insertions(+)

diff --git a/src/js/config/OperationConfig.js b/src/js/config/OperationConfig.js
index 8452dc20..91ab8629 100755
--- a/src/js/config/OperationConfig.js
+++ b/src/js/config/OperationConfig.js
@@ -3335,6 +3335,14 @@ var OperationConfig = {
             },
         ]
     },
+    "Detach PGP Cleartext": {
+        description: "",
+        run: PGP.runDetachClearsig,
+        inputType: "string",
+        outputType: "HTML",
+        args: [
+        ],
+    },
     "Add PGP ASCII Armor": {
         description: "",
         run: PGP.runAddArmor,
diff --git a/src/js/operations/PGP.js b/src/js/operations/PGP.js
index 624ecd02..f141d1ab 100755
--- a/src/js/operations/PGP.js
+++ b/src/js/operations/PGP.js
@@ -511,6 +511,62 @@ var PGP = {
     },
 
 
+    /**
+     * Turns a PGP clearsigned message into a detached signature.
+     *
+     * @param {string} input
+     * @param {Object[]} args
+     * @returns {HTML}
+     */
+    runDetachClearsig: function (input, args) {
+        return new Promise(function(resolve, reject) {
+            try {
+                var message = openpgp.cleartext.readArmored(input);
+            } catch (err) {
+                return reject("Could not read input message: " + err);
+            }
+
+            var cleartext = message.getText();
+            var clearbytes = openpgp.util.str2Uint8Array(cleartext);
+
+            var signature = message.packets.filterByTag(openpgp.enums.packet.signature);
+            var rawSignatureBytes = signature.write();
+
+            var armoredMessage = openpgp.armor.encode(
+                openpgp.enums.armor.message,
+                rawSignatureBytes
+            );
+            armoredMessage = armoredMessage.replace(
+                "-----BEGIN PGP MESSAGE-----\r\n",
+                "-----BEGIN PGP SIGNATURE-----\r\n"
+            );
+            armoredMessage = armoredMessage.replace(
+                "-----END PGP MESSAGE-----\r\n",
+                "-----END PGP SIGNATURE-----\r\n"
+            );
+
+            var files = [{
+                fileName: "msg",
+                size: cleartext.length,
+                contents: cleartext,
+                bytes: clearbytes,
+            }, {
+                fileName: "msg.asc",
+                size: armoredMessage.length,
+                contents: armoredMessage,
+                bytes: openpgp.util.str2Uint8Array(armoredMessage),
+            }, {
+                fileName: "msg.sig",
+                size: rawSignatureBytes.length,
+                contents: openpgp.util.Uint8Array2str(rawSignatureBytes),
+                bytes: rawSignatureBytes,
+            }];
+
+            resolve(Utils.displayFilesAsHTML(files));
+        });
+    },
+
+
     /**
      * Turns raw PGP bytes into an ASCII armored string.
      *