From cd2fb13b3e9ced39059f3d6572fd8806d0026d2e Mon Sep 17 00:00:00 2001
From: Aldo Cortesi <aldo@nullcube.com>
Date: Sun, 17 May 2015 11:04:53 +1200
Subject: [PATCH] websockets: replace the "raw" with a simpler mechanism

You can now say "knone" to specifiy that no key should be generated
under any circumstances.
---
 libpathod/language/websockets.py              | 23 +++++++++++--------
 libpathod/templates/docs_lang_websockets.html | 15 ++----------
 test/test_language_websocket.py               | 11 +++++++--
 3 files changed, 25 insertions(+), 24 deletions(-)

diff --git a/libpathod/language/websockets.py b/libpathod/language/websockets.py
index 599cdb886..428f3b4dd 100644
--- a/libpathod/language/websockets.py
+++ b/libpathod/language/websockets.py
@@ -9,7 +9,6 @@ from . import base, generators, actions, message
     wf:fin:rsv1:rsv2:rsv3:mask
     wf:-fin:-rsv1:-rsv2:-rsv3:-mask
 
-    wf:k"mask"
     wf:l234
 """
 
@@ -35,10 +34,6 @@ class Body(base.Value):
     preamble = "b"
 
 
-class Raw(base.CaselessLiteral):
-    TOK = "r"
-
-
 class Fin(base.Boolean):
     name = "fin"
 
@@ -64,6 +59,11 @@ class Key(base.FixedLengthValue):
     length = 4
 
 
+class KeyNone(base.CaselessLiteral):
+    unique_name = "Key"
+    TOK = "knone"
+
+
 class WebsocketFrame(message.Message):
     comps = (
         Body,
@@ -78,9 +78,8 @@ class WebsocketFrame(message.Message):
         actions.PauseAt,
         actions.DisconnectAt,
         actions.InjectAt,
+        KeyNone,
         Key,
-
-        Raw,
     )
     logattrs = ["body"]
     @property
@@ -119,6 +118,10 @@ class WebsocketFrame(message.Message):
     def key(self):
         return self.tok(Key)
 
+    @property
+    def knone(self):
+        return self.tok(KeyNone)
+
     @classmethod
     def expr(klass):
         parts = [i.expr() for i in klass.comps]
@@ -139,7 +142,7 @@ class WebsocketFrame(message.Message):
             tokens.append(
                 Mask(True)
             )
-        if self.mask and self.mask.value and not self.key:
+        if not self.knone and self.mask and self.mask.value and not self.key:
             tokens.append(
                 Key(base.TokValueLiteral(os.urandom(4)))
             )
@@ -159,7 +162,9 @@ class WebsocketFrame(message.Message):
         )
         if self.mask and self.mask.value:
             frameparts["mask"] = True
-        if self.key:
+        if self.knone:
+            frameparts["masking_key"] = None
+        elif self.key:
             key = self.key.values(settings)[0][:]
             frameparts["masking_key"] = key
         for i in ["opcode", "fin", "rsv1", "rsv2", "rsv3", "mask"]:
diff --git a/libpathod/templates/docs_lang_websockets.html b/libpathod/templates/docs_lang_websockets.html
index 9eb1ec25e..a77ac2510 100644
--- a/libpathod/templates/docs_lang_websockets.html
+++ b/libpathod/templates/docs_lang_websockets.html
@@ -48,7 +48,8 @@
             <td> k<a href="#valuespec">VALUE</a> </td>
             <td>
                 Set the masking key. The resulting value must be exactly 4
-                bytes long.
+                bytes long. The special form <b>knone</b> specifies that no key
+                should be set, even if the mask bit is on.
             </td>
         </tr>
 
@@ -67,18 +68,6 @@
             </td>
         </tr>
 
-        <tr>
-            <td> r </td>
-            <td>
-                Create a "raw" frame:
-                <ul>
-                    <li> Don't auto-generate the masking key if the mask flag is
-                    set </li>
-
-                    <li> Don't set the mask flag if masking key is set. </li>
-            </td>
-        </tr>
-
         <tr>
             <td> [-]rsv1 </td>
             <td>
diff --git a/test/test_language_websocket.py b/test/test_language_websocket.py
index 5e2ccb88f..f9e8310a5 100644
--- a/test/test_language_websocket.py
+++ b/test/test_language_websocket.py
@@ -17,7 +17,7 @@ class TestWebsocketFrame:
             "wf:b'foo'",
             "wf:cbinary",
             "wf:c1",
-            "wf:r",
+            "wf:mask:knone",
             "wf:fin",
             "wf:fin:rsv1:rsv2:rsv3:mask",
             "wf:-fin:-rsv1:-rsv2:-rsv3:-mask",
@@ -67,7 +67,7 @@ class TestWebsocketFrame:
         assert self.fr("wf:ctext").header.opcode ==\
             netlib.websockets.OPCODE.TEXT
 
-    def test_auto_raw(self):
+    def test_construction(self):
         # Simple server frame
         frm = self.fr("wf:b'foo'")
         assert not frm.header.mask
@@ -99,3 +99,10 @@ class TestWebsocketFrame:
         # We're reading back a corrupted frame - the first 3 characters of the
         # mask is mis-interpreted as the payload
         assert frm.payload == "abc"
+
+    def test_knone(self):
+        tutils.raises(
+            "expected 4 bytes",
+            self.fr,
+            "wf:b'foo':mask:knone",
+        )