Add *MAX-LINE-LENGTH* and *MAX-HEADER-LINE-LENGTH*

conditions.lisp

@@ -82,3 +82,13 @@ Read character ~S, but expected ~:[a member of ~S~;~S~]."
   (:documentation "A condition of this type is signaled if an
 unexpected character \(octet) is read while reading from a chunked
 stream with input chunking enabled."))
+
+(define-condition input-exceeded-limit (chunga-error)
+  ((maximum :initarg :maximum
+	    :documentation "The limit which was exceeded."))
+  (:report (lambda (condition stream)
+	     (with-slots (maximum)
+		 condition
+	       (format stream "Input exceeded ~d characters." maximum))))
+  (:documentation "A condition of this type is signaled if an
+maximum-character limit is exceeded."))

read.lisp

@@ -100,8 +100,11 @@ Additionally logs this string to LOG-STREAM if it is not NIL."
   (let ((result
          (with-output-to-string (line)
            (loop for char-seen-p = nil then t
+                 for count from 0
                  for char = (read-char* stream nil)
                  for is-cr-p = (and char (char= char #\Return))
+                 when (and *max-line-length* (> count *max-line-length*))
+                   do (error 'input-exceeded-limit :maximum *max-line-length*)
                  until (or (null char)
                            is-cr-p
                            (and *accept-bogus-eols*
@@ -155,7 +158,8 @@ separated by commas.  Header lines which are spread across
 multiple lines are recognized and treated correctly.  Additonally
 logs the header lines to LOG-STREAM if it is not NIL."
   (let (headers
-        (*current-error-message* "While reading HTTP headers:"))
+        (*current-error-message* "While reading HTTP headers:")
+        (*max-line-length* (or *max-header-line-length* *max-line-length*)))
     (labels ((read-header-line ()
                "Reads one header line, considering continuations."
                (with-output-to-string (header-line)

specials.lisp

@@ -78,6 +78,13 @@ variable has a true value, though.")
   "A `buffer' for one character.  Used by PEEK-CHAR* and
 UNREAD-CHAR*.")
 
+(defvar *max-line-length* nil
+  "Maximum length of a line.  If NIL, lines may be any length.")
+
+(defvar *max-header-line-length* nil
+  "Maximum length of HTTP header lines.  If NIL, defaults to
+*MAX-LINE-LENGTH*.")
+
 (pushnew :chunga *features*)
 
 ;; stuff for Nikodemus Siivola's HYPERDOC