add git-annex network dispatchers

README.md

@@ -92,11 +92,12 @@ the `network.trusted_uuid` list. NetworkManager UUIDs may be discovered using
 `nmcli con`.
 
 The list of trusted networks is made available at
-`/usr/local/etc/trusted_networks`. Currently this list is only used to start
-and stop mail syncing (see the section below on Syncing and Scheduling Mail)
-and Tarsnap backups (see the section below on Scheduling Tarsnap), however
-maintaining the list may be useful for starting or stopping other services,
-loading different iptables rules, etc.
+`/usr/local/etc/trusted_networks`. Currently this list is used to start and
+stop mail syncing (see the section below on Syncing and Scheduling Mail),
+Tarsnap backups (see the section below on Scheduling Tarsnap), and the
+git-annex assistant (see the section below on git-annex). Maintaining this list
+may be useful for starting or stopping additional services, loading different
+iptables rules, etc.
 
 ## Mail
 
@@ -181,10 +182,33 @@ variable from `trusted` to `all`.
 If the `tarsnapper.tarsnap.run_on` variable is set to anything other than
 `trusted` or `all`, the timer will never be activated.
 
+## git-annex
+
+[git-annex][19] is installed for file syncing. A systemd service unit for the
+git-annex assistant is enabled and started by default. To prevent this, remove
+the `git-annex` variable from the config.
+
+NetworkManager dispatchers are installed to stop the service when connecting to
+untrusted networks. This helps to avoid having network tasks that may leak
+personally identifiable information running in the background when connected to
+untrusted networks.
+
+Note that this behaviour is slightly different than that of the NetworkManager
+dispatchers included for syncing mail and performing Tarsnap backups. Those
+timers are disabled by default, only started *after* a connection to a trusted
+network has been established, and immediately stopped after disconnecting from
+any network.  Conversely, the git-annex assistant is started by default,
+stopped *before* connecting to an untrusted network, and immediately started
+after disconnecting from any network.
+
+If the `git-annex.stopped_on` variable is set to anything other than
+`untrusted`, the NetworkManager dispatchers will not be installed, resulting in
+the git-annex assistant service not being stopped on untrusted networks.
+
 ## Known Issues
 
-* [tpfanco][19], normally installed as part of the `thinkpad` role is currently
-  [unavailable in the AUR][20]. No ThinkPad fan control software is currently
+* [tpfanco][20], normally installed as part of the `thinkpad` role is currently
+  [unavailable in the AUR][21]. No ThinkPad fan control software is currently
   installed.
 
 
@@ -206,5 +230,6 @@ If the `tarsnapper.tarsnap.run_on` variable is set to anything other than
 [16]: https://www.tarsnap.com/
 [17]: https://www.tarsnap.com/gettingstarted.html
 [18]: https://github.com/miracle2k/tarsnapper
-[19]: https://code.google.com/p/tpfanco/
-[20]: https://aur.archlinux.org/packages/?O=0&K=tpfanco
+[19]: https://git-annex.branchable.com/
+[20]: https://code.google.com/p/tpfanco/
+[21]: https://aur.archlinux.org/packages/?O=0&K=tpfanco

group_vars/all

@@ -78,3 +78,6 @@ tarsnapper:
   timer:
     frequency: 1h
     run_on: trusted
+
+git-annex:
+    stopped_on: untrusted

roles/git-annex/tasks/main.yml

@@ -4,8 +4,17 @@
   tags:
     - aur
 
-- name: Push git-annex service file
+- name: Push git-annex assistant service file
   copy: src=git-annex.service dest=/etc/systemd/system/git-annex@.service
 
-- name: Enable and start git-annex service timer
+- name: Enable and start git-annex assistant service
   service: name="git-annex@{{ user.name }}.service" enabled=yes state=started
+  when: git-annex is defined
+
+- name: Push dispatcher to disable git-annex assistant on untrusted networks
+  template: src=gitannex_disabler.sh.j2 dest=/etc/NetworkManager/dispatcher.d/pre-up.d/10gitannex_disabler mode=0755
+  when: git-annex.stopped_on == "untrusted"
+
+- name: Push dispatcher to activate git-annex assistant on network disconnect
+  template: src=gitannex_enabler.sh.j2 dest=/etc/NetworkManager/dispatcher.d/10gitannex mode=0755
+  when: git-annex.stopped_on == "untrusted"

roles/git-annex/templates/gitannex_disabler.sh.j2

@@ -0,0 +1,8 @@
+#!/bin/sh
+# {{ ansible_managed }}
+
+if ! grep -q $CONNECTION_UUID /usr/local/etc/trusted_networks; then
+    systemctl stop git-annex@{{ user.name }}.service
+fi
+
+exit 0

roles/git-annex/templates/gitannex_enabler.sh.j2

@@ -0,0 +1,12 @@
+#!/bin/sh
+# {{ ansible_managed }}
+
+action="$2"
+
+case $action in
+    down)
+        systemctl start git-annex@{{ user.name }}.service
+        ;;
+esac
+
+exit 0