http: disable whitespace for special headers

src/llhttp/http.ts

@@ -45,6 +45,7 @@ const NODES: ReadonlyArray<string> = [
   'header_field_start',
   'header_field',
   'header_field_colon',
+  'header_field_colon_discard_ws',
   'header_field_general',
   'header_field_general_otherwise',
   'header_value_discard_ws',
@@ -361,13 +362,32 @@ export class HTTP {
       .select(SPECIAL_HEADERS, this.store('header_state', 'header_field_colon'))
       .otherwise(this.resetHeaderState('header_field_general'));
 
+    const onInvalidHeaderFieldChar =
+      p.error(ERROR.INVALID_HEADER_TOKEN, 'Invalid header field char');
+
+    const checkLenientFlagsOnColon =
+      this.testFlags(FLAGS.LENIENT, {
+        1: n('header_field_colon_discard_ws'),
+      }, span.headerField.end().skipTo(onInvalidHeaderFieldChar));
+
     n('header_field_colon')
-      .match(' ', n('header_field_colon'))
+      // https://datatracker.ietf.org/doc/html/rfc7230#section-3.2.4
+      // Whitespace character is not allowed between the header field-name
+      // and colon. If the next token matches whitespace then throw an error.
+      //
+      // Add a check for the lenient flag. If the lenient flag is set, the
+      // whitespace token is allowed to support legacy code not following
+      // http specs.
+      .peek(' ', checkLenientFlagsOnColon)
       .peek(':', span.headerField.end().skipTo(n('header_value_discard_ws')))
       // Fallback to general header, there're additional characters:
       // `Connection-Duration` instead of `Connection` and so on.
       .otherwise(this.resetHeaderState('header_field_general'));
 
+    n('header_field_colon_discard_ws')
+      .match(' ', n('header_field_colon_discard_ws'))
+      .otherwise(n('header_field_colon'));
+
     n('header_field_general')
       .match(this.TOKEN, n('header_field_general'))
       .otherwise(n('header_field_general_otherwise'));

test/request/connection.md

@@ -348,6 +348,52 @@ off=78 message complete
 off=78 error code=22 reason="Pause on CONNECT/Upgrade"
 ```
 
+### Invalid whitespace token with `Connection` header field
+
+<!-- meta={"type": "request"} -->
+```http
+PUT /url HTTP/1.1
+Connection : upgrade
+Content-Length: 4
+Upgrade: ws
+
+abcdefgh
+```
+
+```log
+off=0 message begin
+off=4 len=4 span[url]="/url"
+off=19 len=10 span[header_field]="Connection"
+off=30 error code=10 reason="Invalid header field char"
+```
+
+### Invalid whitespace token with `Connection` header field (lenient)
+
+<!-- meta={"type": "request-lenient"} -->
+```http
+PUT /url HTTP/1.1
+Connection : upgrade
+Content-Length: 4
+Upgrade: ws
+
+abcdefgh
+```
+
+```log
+off=0 message begin
+off=4 len=4 span[url]="/url"
+off=19 len=11 span[header_field]="Connection "
+off=32 len=7 span[header_value]="upgrade"
+off=41 len=14 span[header_field]="Content-Length"
+off=57 len=1 span[header_value]="4"
+off=60 len=7 span[header_field]="Upgrade"
+off=69 len=2 span[header_value]="ws"
+off=75 headers complete method=4 v=1/1 flags=134 content_length=4
+off=75 len=4 span[body]="abcd"
+off=79 message complete
+off=79 error code=22 reason="Pause on CONNECT/Upgrade"
+```
+
 ## `upgrade`
 
 ### Setting a flag and pausing

test/request/content-length.md

@@ -151,6 +151,54 @@ off=57 len=8 span[header_value]="identity"
 off=69 headers complete method=4 v=1/1 flags=320 content_length=1
 ```
 
+## Invalid whitespace token with `Content-Length` header field
+
+<!-- meta={"type": "request"} -->
+```http
+PUT /url HTTP/1.1
+Connection: upgrade
+Content-Length : 4
+Upgrade: ws
+
+abcdefgh
+```
+
+```log
+off=0 message begin
+off=4 len=4 span[url]="/url"
+off=19 len=10 span[header_field]="Connection"
+off=31 len=7 span[header_value]="upgrade"
+off=40 len=14 span[header_field]="Content-Length"
+off=55 error code=10 reason="Invalid header field char"
+```
+
+## Invalid whitespace token with `Content-Length` header field (lenient)
+
+<!-- meta={"type": "request-lenient"} -->
+```http
+PUT /url HTTP/1.1
+Connection: upgrade
+Content-Length : 4
+Upgrade: ws
+
+abcdefgh
+```
+
+```log
+off=0 message begin
+off=4 len=4 span[url]="/url"
+off=19 len=10 span[header_field]="Connection"
+off=31 len=7 span[header_value]="upgrade"
+off=40 len=15 span[header_field]="Content-Length "
+off=57 len=1 span[header_value]="4"
+off=60 len=7 span[header_field]="Upgrade"
+off=69 len=2 span[header_value]="ws"
+off=75 headers complete method=4 v=1/1 flags=134 content_length=4
+off=75 len=4 span[body]="abcd"
+off=79 message complete
+off=79 error code=22 reason="Pause on CONNECT/Upgrade"
+```
+
 ## Funky `Content-Length` with body
 
 <!-- meta={"type": "request"} -->