Zope 2

Zope sends malformed Vary header

Bug #143893 reported by Alexander Limi on 2007-03-25

Affects		Status	Importance	Assigned to	Milestone
	Zope 2	Fix Released	Medium	Martijn Pieters

Bug Description

From http://dev.plone.org/plone/ticket/5786:

"""
We have a proxy that checks the web site before allowing access, and if there is a mistake, we can't connect to your web site.

Your web site answers as a vary accept-encoding which is normal, but the next value is not correct. The line return for this Vary is "\n" instead of being "\r\n".

"""

Wichert adds:

"""
From ZPublisher.HTTPResponse.HTTPResponse.setHeader:

        key = name.lower()
        if accumulate_header(key):
            self.accumulated_headers = (
                "%s%s: %s\n" % (self.accumulated_headers, name, value))
            return

Notice how that uses \n
"""

This seems to be an issue in Zope. I'm not sure what the specs say, but it seems like both \r\n is required here.

Full case history:

http://dev.plone.org/plone/ticket/5786

Tags:

Revision history for this message

Alexander Limi (limi) wrote on 2007-03-25:

And on IRC, Wichert added:

"HTTP RFCs say headers are \r\n seperated"

Revision history for this message

Christian Theune (ctheune) wrote on 2007-03-26:

That's my interpretation of RFC2616 as well:

"HTTP/1.1 defines the sequence CR LF as the end-of-line marker for
all protocol elements except the entity-body (see appendix 19.3 for
tolerant applications). The end-of-line marker within an
entity-body is defined by its associated media type, as described
in section 3.7.

CRLF = CR LF
"

Revision history for this message

Martijn Pieters (mjpieters) wrote on 2007-03-26:

Status: Pending => Accepted

Supporters added: mj

Yes, internally ZPublisher.HTTPResponse deliniates headers with only newline, but ZServer.HTTPResponse then uses '\r\n' to write out the headers. The end-result for the browser is '\r\n' delimeted headers.

There is a bug here though, but only when using addHeader; self.accumulated_headers is output directly, without cleaning up the header capitalisation (a SHOULD), and with \n separation instead of \r\n (a MUST). I'll fix the latter.

Now, if the Vary header was added using addHeader it will get \n deliminations indeed.

Revision history for this message

Martijn Pieters (mjpieters) wrote on 2007-03-27:

Status: Accepted => Resolved

Fix checked in for Zope 2.9:

http://svn.zope.org/Zope/branches/2.9/?rev=73721&view=rev

Zope 2.10:

http://svn.zope.org/Zope/branches/2.10/?rev=73722&view=rev

and Zope trunk:

http://svn.zope.org/Zope/trunk/?rev=73723&view=rev