Automatically decompress client bodies.

Signed-off-by: Laura <l@veriny.tf>
Fuyukai · Jul 3, 2017 · ab796d2 · ab796d2
1 parent 39bb2ce
commit ab796d2
Show file tree

Hide file tree

Showing 3 changed files with 64 additions and 4 deletions.
diff --git a/docs/changelog.rst b/docs/changelog.rst
@@ -3,7 +3,7 @@ Kyoukai Changelog
 
 Here you can see the list of changes between each Kyoukai release.
 
-Version 2.x.x
+Version 2.2.1
 -------------
 
   - Add the ability to override the context class created.
@@ -14,6 +14,8 @@ Version 2.x.x
 
   - Explicitly handle :class:`werkzeug.exceptions.BadRequestKeyError` in app processing.
 
+  - Decompress client body data when a Content-Encoding is detected in the httptools backend.
+
 Version 2.2.0
 -------------
 

diff --git a/kyoukai/app.py b/kyoukai/app.py
@@ -15,7 +15,7 @@
 from kyoukai.asphalt import HTTPRequestContext
 from kyoukai.blueprint import Blueprint
 
-__version__ = "2.2.0"
+__version__ = "2.2.1"
 
 logger = logging.getLogger("Kyoukai")
 

diff --git a/kyoukai/backends/httptools_.py b/kyoukai/backends/httptools_.py
@@ -4,9 +4,11 @@
 """
 import asyncio
 import base64
+import gzip
 import logging
 import traceback
 import warnings
+import zlib
 from io import BytesIO
 
 import httptools
@@ -20,32 +22,53 @@
 CRITICAL_ERROR_TEXT = """HTTP/1.0 500 INTERNAL SERVER ERROR
 Server: Kyoukai
 X-Powered-By: Kyoukai
+X-HTTP-Backend: httptools
 Content-Type: text/html; charset=utf-8
 Content-Length: 310
 
 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2 Final//EN">
 <title>Critical Server Error</title>
 <h1>Critical Server Error</h1>
 <p>An unrecoverable error has occurred within Kyoukai.
-If you are the developer, please report this at <a href="https://github.com/SunDwarf/Kyoukai">the Kyoukai issue
-tracker.</a>
+If you are the developer, please report this at <a href="https://github.com/SunDwarf/Kyoukai">the 
+Kyoukai issue tracker.</a>
 """.replace("\n", "\r\n")
 
 HTTP_SWITCHING_PROTOCOLS = """HTTP/1.1 101 SWITCHING PROTOCOLS
 Connection: Upgrade
 Upgrade: h2c
 Server: Kyoukai
+X-Powered-By: Kyoukai
+X-HTTP-Backend: httptools
+Content-Length: 0
+
+""".replace("\n", "\r\n")
+
+HTTP_TOO_BIG = """HTTP/1.1 413 PAYLOAD TOO LARGE
+Server: Kyoukai
+X-Powered-By: Kyoukai
+X-HTTP-Backend: httptools
 Content-Length: 0
 
 """.replace("\n", "\r\n")
 
+HTTP_INVALID_COMPRESSION = """HTTP/1.1 400 BAD REQUEST
+Server: Kyoukai
+X-Powered-By: Kyoukai
+X-HTTP-Backend: httptools
+Content-Length: 25
+
+Invalid compressed data
+""".replace("\n", "\r\n")
+
 PROTOCOL_CLASS = "KyoukaiProtocol"
 
 
 class KyoukaiProtocol(asyncio.Protocol):  # pragma: no cover
     """
     The base protocol for Kyoukai using httptools for a HTTP/1.0 or HTTP/1.1 interface.
     """
+    MAX_BODY_SIZE = 12 * 1024 * 1024
 
     def __init__(self, component, parent_context: Context,
                  server_ip: str, server_port: int):
@@ -138,6 +161,10 @@ def on_body(self, body: bytes):
         :param body: The body text.
         """
         self.body.write(body)
+        if self.body.tell() >= self.MAX_BODY_SIZE:
+            # write a "too big" message
+            self.write(HTTP_TOO_BIG)
+            self.close()
 
     def on_url(self, url: bytes):
         """
@@ -338,6 +365,37 @@ async def _wait(self):
         version = self.parser.get_http_version()
         method = self.parser.get_method().decode()
 
+        for header, value in self.headers:
+            # check if a content-encoding has been passed
+            if header == "Content-Encoding" and body is not None:
+                # no special encoding
+                if value == "identity":
+                    pass
+
+                # gzip, decompress as such
+                elif value == "gzip":
+                    self.logger.debug("Decoding body data as gzip.")
+                    try:
+                        decompressed_data = gzip.decompress(body.read())
+                    except zlib.error:
+                        self.write(HTTP_INVALID_COMPRESSION)
+                        self.close()
+                        return
+
+                    body = BytesIO(decompressed_data)
+
+                # deflate, decompress as such
+                elif value == "deflate":
+                    z = zlib.decompressobj(6, zlib.DEFLATED, -zlib.MAX_WBITS, zlib.DEF_MEM_LEVEL, 0)
+                    try:
+                        decompressed_data = z.decompress(body.read())
+                    except zlib.error:
+                        self.write(HTTP_INVALID_COMPRESSION)
+                        self.close()
+                        return
+                else:
+                    self.logger.error("Unknown Content-Encoding sent by client: {}".format(value))
+
         new_environ = to_wsgi_environment(headers=self.headers, method=method, path=self.full_url,
                                           http_version=version, body=body)