Bug#555674: apt: Failure to update (with network down) marks all packages untrusted

[Josh Triplett <josh@joshtriplett.org>]

Package: apt
Version: 0.7.24
Severity: normal

If apt fails to download package lists, such as with the network down,
it will mark all packages as untrusted.

Steps to reproduce:

1) Bring down the network interface.
2) apt-get update, or aptitude update.  Either will fail, specifically
   by failing to resolve the domain names.
3) Open up aptitude, and observe the 'U' next to every package.
   Attempting to install one will bring up the untrusted packages
   warning.

- Josh Triplett

-- Package-specific info:

-- apt-config dump --

APT "";
APT::Architecture "amd64";
APT::Build-Essential "";
APT::Build-Essential:: "build-essential";
APT::Install-Recommends "1";
APT::Install-Suggests "0";
APT::Acquire "";
APT::Acquire::Translation "environment";
APT::NeverAutoRemove "";
APT::NeverAutoRemove:: "^linux-image.*";
APT::NeverAutoRemove:: "^linux-restricted-modules.*";
Dir "/";
Dir::State "var/lib/apt/";
Dir::State::lists "lists/";
Dir::State::cdroms "cdroms.list";
Dir::State::userstatus "status.user";
Dir::State::status "/var/lib/dpkg/status";
Dir::Cache "var/cache/apt/";
Dir::Cache::archives "archives/";
Dir::Cache::srcpkgcache "srcpkgcache.bin";
Dir::Cache::pkgcache "pkgcache.bin";
Dir::Etc "etc/apt/";
Dir::Etc::sourcelist "sources.list";
Dir::Etc::sourceparts "sources.list.d";
Dir::Etc::vendorlist "vendors.list";
Dir::Etc::vendorparts "vendors.list.d";
Dir::Etc::main "apt.conf";
Dir::Etc::parts "apt.conf.d";
Dir::Etc::preferences "preferences";
Dir::Etc::preferencesparts "preferences.d";
Dir::Bin "";
Dir::Bin::methods "/usr/lib/apt/methods";
Dir::Bin::dpkg "/usr/bin/dpkg";
Dir::Log "var/log/apt";
Dir::Log::Terminal "term.log";
DPkg "";
DPkg::Pre-Install-Pkgs "";
DPkg::Pre-Install-Pkgs:: "/usr/bin/apt-listchanges --apt || test $? -ne 10";
DPkg::Pre-Install-Pkgs:: "/usr/sbin/dpkg-preconfigure --apt || true";
DPkg::Tools "";
DPkg::Tools::Options "";
DPkg::Tools::Options::/usr/bin/apt-listchanges "";
DPkg::Tools::Options::/usr/bin/apt-listchanges::Version "2";
DPkg::Post-Invoke "";
DPkg::Post-Invoke:: "if [ -x /usr/bin/debsums ]; then /usr/bin/debsums --generate=nocheck -sp /var/cache/apt/archives; fi";

-- (no /etc/apt/preferences present) --


-- /etc/apt/sources.list --

deb http://ftp.us.debian.org/debian/ unstable main
deb-src http://ftp.us.debian.org/debian/ unstable main

deb http://ftp.us.debian.org/debian/ experimental main
deb-src http://ftp.us.debian.org/debian/ experimental main

deb http://www.emdebian.org/debian/ unstable main

-- System Information:
Debian Release: squeeze/sid
  APT prefers unstable
  APT policy: (500, 'unstable'), (1, 'experimental')
Architecture: amd64 (x86_64)

Kernel: Linux 2.6.31-1-amd64 (SMP w/2 CPU cores)
Locale: LANG=en_US.UTF-8, LC_CTYPE=en_US.UTF-8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash

Versions of packages apt depends on:
ii  debian-archive-keyring        2009.01.31 GnuPG archive keys of the Debian a
ii  libc6                         2.10.1-6   GNU C Library: Shared libraries
ii  libgcc1                       1:4.4.2-2  GCC support library
ii  libstdc++6                    4.4.2-2    The GNU Standard C++ Library v3

apt recommends no packages.

Versions of packages apt suggests:
pn  apt-doc                       <none>     (no description available)
ii  aptitude                      0.6.0.1-1  terminal-based package manager (te
ii  bzip2                         1.0.5-3    high-quality block-sorting file co
ii  dpkg-dev                      1.15.4.1   Debian package development tools
ii  lzma                          4.43-14    Compression method of 7z format in
ii  python-apt                    0.7.13.3   Python interface to libapt-pkg

-- no debconf information