Hello,
I encountered a bug in the HTTP header parsing bug when trying to
download a file via Guix. The response had a Content-Type header, but
with no value, like so:
Content-Type:
>From reading the W3C spec[0], an unknown Content-Type header can be
treated as if it were an application/octet-stream type. I'm unsure if
that means even Content-Type values that have invalid syntax should be
accepted or not, so I didn't try to handle them. I'm not even sure if
we should be translating the empty string to application/octet-stream.
I know that it shouldn't throw an excpetion, but maybe it should just
return the empty list and the user can decide how to interpret it?
Anyway, here's a patch to get the ball rolling.
>From c9994a7b94ab2c43adfea2980da99515e6292e16 Mon Sep 17 00:00:00 2001
From: David Thompson <dthomps...@worcester.edu>
Date: Thu, 23 Jul 2015 22:07:53 -0400
Subject: [PATCH] web: http: Accept blank Content-Type headers.
* module/web/http.scm (parse-media-type): Return
'application/octet-stream' when given the empty string.
* test-suite/tests/web-http.test ("entity headers"): Add test.
---
module/web/http.scm | 10 +++++++---
test-suite/tests/web-http.test | 1 +
2 files changed, 8 insertions(+), 3 deletions(-)
diff --git a/module/web/http.scm b/module/web/http.scm
index f8aa8db..6f0f6fd 100644
--- a/module/web/http.scm
+++ b/module/web/http.scm
@@ -271,9 +271,13 @@ as an ordered alist."
(and idx (= idx (string-rindex str #\/))
(not (string-index str separators-without-slash)))))
(define (parse-media-type str)
- (if (validate-media-type str)
- (string->symbol str)
- (bad-header-component 'media-type str)))
+ (cond
+ ((string-null? str)
+ 'application/octet-stream)
+ ((validate-media-type str)
+ (string->symbol str))
+ (else
+ (bad-header-component 'media-type str))))
(define* (skip-whitespace str #:optional (start 0) (end (string-length str)))
(let lp ((i start))
diff --git a/test-suite/tests/web-http.test b/test-suite/tests/web-http.test
index c59674f..0675dbc 100644
--- a/test-suite/tests/web-http.test
+++ b/test-suite/tests/web-http.test
@@ -267,6 +267,7 @@
(pass-if-parse content-range "bytes */30" '(bytes * 30))
(pass-if-parse content-type "foo/bar" '(foo/bar))
(pass-if-parse content-type "foo/bar; baz=qux" '(foo/bar (baz . "qux")))
+ (pass-if-parse content-type "" '(application/octet-stream))
(pass-if-parse expires "Tue, 15 Nov 1994 08:12:31 GMT"
(string->date "Tue, 15 Nov 1994 08:12:31 +0000"
"~a, ~d ~b ~Y ~H:~M:~S ~z"))
--
2.4.3
--
David Thompson
GPG Key: 0FF1D807
