bug#13374: 24.?; open-gnutls-stream insecurity

[Oleksii Shevchuk]

Hi list!

open-gnutls-stream wrapper doesn't pass :verify-hostname-error t
:verify-error t to gnutls-negotiate. So MitM is possible when you use
gnus and other packages. 

Even with :verify-hostname-error t :verify-error t gnutls-negotiate
doesn't produce error with selfsigned CA certificate, when :type
'gnutls-x509pki passed.

I use next in my .gnus:

(defun open-gnutls-stream (name buffer host service)
  (gnutls-negotiate :process (open-network-stream name buffer host service)
                    :hostname host
                    :verify-hostname-error t :verify-error t))

Works for me.

// ----

In GNU Emacs 24.3.50.1 (x86_64-pc-linux-gnu, X toolkit)
 of 2013-01-06 on BlackICE
Bzr revision: cyd@gnu.org-20130106025857-h1wkwx5cwvekj4l1
Windowing system distributor `The X.Org Foundation', version 11.0.11300000
System Description:     Gentoo Base System release 2.2

Configured using:
 `configure --prefix=/usr --build=x86_64-pc-linux-gnu
 --host=x86_64-pc-linux-gnu --mandir=/usr/share/man
 --infodir=/usr/share/info --datadir=/usr/share --sysconfdir=/etc
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 --program-transform-name=s/emacs-[0-9].*/emacs-24-vcs/
 --infodir=/usr/share/info/emacs-24-vcs
 --enable-locallisppath=/etc/emacs:/usr/share/emacs/site-lisp
 --with-crt-dir=/usr/lib/gcc/x86_64-pc-linux-gnu/4.7.2/../../../../lib64
 --with-gameuser=games --without-compress-info --without-hesiod
 --without-kerberos --without-kerberos5 --with-gpm --with-dbus
 --with-gnutls --with-xml2 --without-selinux --with-wide-int
 --with-sound --with-x --without-ns --without-gconf --with-gsettings
 --without-toolkit-scroll-bars --with-gif --with-jpeg --with-png
 --with-rsvg --with-tiff --with-xpm --without-imagemagick --with-xft
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 --without-xaw3d GENTOO_PACKAGE=app-editors/emacs-vcs-24.3.9999
 EBZR_BRANCH=trunk EBZR_REVNO=111428'

Important settings:
  value of $LC_ALL: ru_RU.UTF-8
  value of $LANG: russian
  locale-coding-system: utf-8-unix
  default enable-multibyte-characters: t