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From: "Anthony J. Bentley" <>
Subject: Content-Security-Policy for man.cgi
Date: Sun, 10 Nov 2019 01:59:21 -0700	[thread overview]
Message-ID: <37020-1573376361.432557@hhtH.9ww_.rVWG> (raw)


Modern browsers respect the Content-Security-Policy header, which
restricts where dynamic resources like CSS and JavaScript can be
specified in an HTML document.

Since hosts manuals from many sources, and there's
always danger of a bug in mandoc that allows dangerous HTML content
through, a policy of "default-src 'none'; style-src 'self'" would be
appropriate: this allows external stylesheets loaded from a URL on
the same domain, but prohibits external links and inline CSS; scripts
are not allowed at all. (mandoc(1) no longer generates inline styles
at all, right?)

Index: cgi.c
RCS file: /cvs/src/usr.bin/mandoc/cgi.c,v
retrieving revision 1.106
diff -u -p -r1.106 cgi.c
--- cgi.c	1 Oct 2019 17:54:04 -0000	1.106
+++ cgi.c	10 Nov 2019 08:48:46 -0000
@@ -336,6 +336,7 @@ resp_begin_http(int code, const char *ms
 	printf("Content-Type: text/html; charset=utf-8\r\n"
 	     "Cache-Control: no-cache\r\n"
+	     "Content-Security-Policy: default-src 'none'; style-src 'self';\r\n"
 	     "Pragma: no-cache\r\n"
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             reply	other threads:[~2019-11-10  8:59 UTC|newest]

Thread overview: 6+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2019-11-10  8:59 Anthony J. Bentley [this message]
2019-11-10 10:22 ` Ingo Schwarze
2019-11-10 13:02   ` Anthony J. Bentley
2019-11-10 17:47     ` Ingo Schwarze
2019-11-10 20:09       ` Anthony J. Bentley
2019-11-10 20:57         ` Ingo Schwarze

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