- From: Yoav Weiss <yoav@yoav.ws>
- Date: Wed, 9 Jan 2013 10:07:29 +0100
- To: Adam Barth <w3c@adambarth.com>
- Cc: "public-webappsec@w3.org" <public-webappsec@w3.org>
- Message-ID: <CACj=BEjwRrGwyKyKt+MpyD5+BXBSVfnL_XwCt880x3VN1YjopA@mail.gmail.com>
OK, so the sentence "This document also uses the ABNF extension "#rule" as defined in HTTP 1.1." (and the extension itself) is what I missed. Thanks! On Tue, Jan 8, 2013 at 11:36 PM, Adam Barth <w3c@adambarth.com> wrote: > The header is first split on , and then each of the comma-separated > values are interpreted as if they were sent in separate > Content-Security-Policy headers: > > > https://dvcs.w3.org/hg/content-security-policy/raw-file/tip/csp-specification.dev.html#content-security-policy-header-field > > "Content-Security-Policy:" 1#policy > > The 1#policy means 1 or more comma separated policies. > > Adam > > > On Tue, Jan 8, 2013 at 7:55 AM, Yoav Weiss <yoav@yoav.ws> wrote: > > Since section 3.1.1 permits sending multiple CSP headers, according to > RFC > > 2616 (http://www.w3.org/Protocols/rfc2616/rfc2616-sec4.html#sec4.2), the > > following should be semantically equivalent: > > Content-Security-Policy: script-src http://bla.com > > Content-Security-Policy: default-src http://bla.org > > Content-Security-Policy: script-src http://bla.com/blabla > > and > > Content-Security-Policy: script-src http://bla.com, default-src > > http://bla.org, script-src http://bla.com/blabla > > > > Such HTTP header merging can be done by an HTTP proxy. > > > > That raises a couple of questions: > > 1. How does the specification deal with delimiting commas (and the lack > of > > delimiting semi-colons)? > > 2. Do several CSP headers create a single CSP policy, or multiple ones? > > > > From sections 3.1.1 and 3.2.1, I understand that each HTTP header > creates a > > separate CSP policy, and a delimiting semi-colon must be present. > > > > If I understand correctly, while the 3 separate CSP headers create 3 CSP > > policies which will be applied with an "and" relationship, the merged CSP > > header, assuming it will become valid(e.g. by allowing delimiting > commas), > > will ignore the second script-src directive. > > > > That means that HTTP header merging will lead to different policies being > > applied. > > > > Am I missing something? > > > > Yoav >
Received on Wednesday, 9 January 2013 09:07:58 UTC