[pkg-lynx-maint] Bug#791452: lynx: more cases

[Jack Ryan]

Package: lynx
Version: 2.8.9dev1-2
Followup-For: Bug #791452

I am the submitter.  After more tests, there are perhaps multiple bugs
here.  I attempted to change test sites, because
torstatus.blutmagie.de is a large document.

These commands cause lynx to hang:

  env http_proxy=http://127.0.0.1:8118/   lynx http://check.torproject.org/
  env https_proxy=https://127.0.0.1:8118/ lynx https://check.torproject.org/

I suspect that check.torproject.org redirects to https in the first
case.  But why should the redirection fail?  The proxy (privoxy in my
case) should be able to handle either.  I'm not sure if this is a
privoxy bug or a lynx bug.

The proxy is ignored in these cases:

  env http_proxy=http://127.0.0.1:8118/  lynx https://check.torproject.org/
  env http_proxy=http://127.0.0.1:8118/  lynx https://torstatus.blutmagie.de/
  env http_proxy=https://127.0.0.1:8118/ lynx https://torstatus.blutmagie.de/

This works:

  env http_proxy=http://127.0.0.1:8118/ lynx http://torstatus.blutmagie.de/
  env http_proxy=http://localhost:8118/ lynx http://torstatus.blutmagie.de/

  env https_proxy=http://127.0.0.1:8118 http_proxy=http://127.0.0.1:8118\
    lynx -dump https://check.torproject.org/

Apparently blutmagie.de does not do an https redirect.  Strangely, the
only way to access https://check.torproject.org/ over the proxy is to
set both proxy variables.  I have no idea why setting https_proxy
alone is insufficient.

Another complication that I encountered was IPv4 vs IPv6.  Originally
I had this line in the privoxy config:

  listen-address localhost:8118

The effect was that localhost became ::1 (the IPv6 equivelant to
127.0.0.1).  Then lynx would only work if invoked using ::1, not
127.0.0.1.  Firefox is better in this regard.  That is, when Firefox
is told the proxy host is "localhost", it apparently tries both ::1
and 127.0.0.1.  Lynx could be improved to have the same smarts.

Anyway, the fix for me was to force privoxy onto IPv4 (as it seems
silly to use IPv6 for LAN addressing), by configuring privoxy this
way:

  listen-address 127.0.0.1:8118

-- System Information:
Debian Release: 8.1
  APT prefers stable-updates
  APT policy: (500, 'stable-updates'), (500, 'stable')
Architecture: amd64 (x86_64)
Foreign Architectures: i386

Kernel: Linux 3.16.0-4-amd64 (SMP w/2 CPU cores)
Locale: LANG=en_US.utf8, LC_CTYPE=en_US.utf8 (charmap=UTF-8)
Shell: /bin/sh linked to /bin/dash
Init: systemd (via /run/systemd/system)

Versions of packages lynx depends on:
ii  lynx-cur  2.8.9dev1-2+b1

lynx recommends no packages.

lynx suggests no packages.

-- no debconf information