[[!toc levels=2]] # Rationale Tails should be usable by those stuck with dial-up Internet access. Recent events have shown that in some cases, dial-up might be the last option to reach the Internet when broadband operators have been shut down. This was [[discussed on the forum|forum/GNOME_PPP_for_Dial-Up__63__]]. # Roadmap **Next thing to do**: make up our mind wrt. towards which one of the possible solutions we want to go: [[todo/choose_direction_for_PPP_support]]. Possible solutions: * fix [[!debbug 258064]], but GNOME PPP looks dead upstream, so it might be an option to create a custom package handling resolvconf the way we want. * find alternative ways to use WvDial or PPP. Ideal solution: [[todo/NetworkManager:_PSTN_dial-up]] # Research NetworkManager (and ModemManager) have full support for **mobile** modems. But nothing for old school dial-up modems at the moment: see [b.g.o #348330 - Tracker: Integrated PPP support](https://bugzilla.gnome.org/show_bug.cgi?id=348330) Fallback option: provide GNOME PPP, a GUI front-end to old but trusty WvDial. # Dial-up emulation Here is a method to test dial-up PPP connections without resorting to a real modem and a real Internet provider available on the Plain Old Telephony System. It needs a system running Tails and another one (the *gateway*) running standard Debian. So this requires either two computers in the same LAN or runing Tails using virtualization. 1. Prepare the networking stack on the *gateway*: # iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE # sysctl -w net.ipv4.ip_forward=1 2. In Tails, create `.wvdial.conf`: [Dialer Defaults] Baud = 115200 Init = ATZ Init2 = AT%R1 Phone = 192.168.1.2:6789 Username = test Password = test Carrier Check = off Replace the IP address in `Phone` with the IP address of the other system. 3. In Tails, install the `modemu` package. 4. In Tails, remove the default route to let room for the one provided by PPP: # ip route del default 5. On the *gateway* run: # pppd noauth local lock nodefaultroute persist debug nodetach 10.1.2.3:10.4.5.6 pty "nc -l 6789" 6. And fairly quickly (before `pppd` times out), run on Tails: $ sudo modemu -c 'ln -nsf %s /dev/modem ; wvdial -C .wvdial.conf' Repeat the last two steps if the connection is broken at some point. # PPPoE emulation To ensure that PPPoE (broadband DSL) support is not broken by tweaks to PPP configuration files, here is a test procedure. This needs a standard Debian system (the *gateway*), and either a spare wired network card or using virtualization. This reciepe uses `kvm`, but could be easily adapted to other setups: 1. On the *gateway*, install the `pppoe` package. 2. On the *gateway*, create `/etc/ppp/pppoe-server-options`: debug noauth lcp-echo-interval 10 lcp-echo-failure 2 ms-dns 8.8.8.8 defaultroute noipdefault 3. Start KVM, adding those arguments: `-net nic,model=virtio -net tap,ifname=tails`. 4. On the *gateway*, *up* this interface: # ip link set tails up 5. On the *gateway*, start the PPPoE server: # sudo pppoe-server -I tails -F -S test -m 1412 6. On Tails, you can now right-click the NetworkManager icon, and select *Edit connections...*. In the *DSL* tab, click *Add*. *Service name* should be set to `test`. Other settings should not matter. 7. On Tails, left-click the NetworkManager icon and selection the newly created connection. To debug, use `tcpdump`, and look at `/var/log/syslog`. # Implementation ## GNOME PPP As WvDial (and thus GNOME PPP) is not integrated with NetworkManager in any way, the hooks in `/etc/NetworkManager/dispatcher.d` are not normally run upon connection. They will be after adding the following script as `/etc/ppp/ip-up.d/010call-nm-hooks`: #!/bin/sh run-parts --regex='^[a-z0-9-]+(\.sh)?$' /etc/NetworkManager/dispatcher.d --arg="$1" --arg="up" But this will probably has the undesired effect of calling NetworkManager hooks twice when using PPPoE. This does not look like a real issue, but Tor is still restarted twice which is not nice. Answer to this problem is fairly simple: when using WvDial with a good ol' modem, a `SPEED` environment variable is defined when `01call-nm-hooks` runs. Let's simply use this to determine if we should run NetworkManager hooks manually. Remaining issues: * `gnome-ppp` conflicts with `resolvconf`, see [[!debbug 258064]]. * Clarify what groups must the user be part of to run wvdial / gnome-ppp? We've been told [[on the forum|forum/GNOME_PPP_for_Dial-Up__63__#comment-9b26e5014164c5ff0ebd3cc3223f6301]] the answer was `dialout` (which is already the case) and `dip` (which is not).

Optional description of this change:
FormattingHelp Attachments