Added ssh-agent plugin.

This commit is contained in:
Alexis Lahouze 2013-10-01 01:48:44 +02:00
parent 71d2c36a04
commit 90d66808e0
2 changed files with 299 additions and 1 deletions

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@ -2,7 +2,19 @@ Alexis Lahouze's zsh utils.
# Plugins # Plugins
TODO ## ssh-agent
Handles ssh-agent, with a unique global link per user to avoid socket
loss in remote screen after reconnection.
### zstyle parameters
1. `:xals:plugins:ssh-agent verbose`: set to "yes" to be verbose.
2. `:xals:plugins:ssh-agent global_sock`: overrides user global socket
link path (default: `/tmp/ssh-agent-$USER`).
3. `:xals:plugins:ssh-agent enable_root`: set "yes" to enable ssh
agent for root user.
4. `:xals:plugins:ssh-agent lifetime`: set ssh-agent lifetime.
5. `:xals:plugins:ssh-agent identities`: set identities to add in
agent.
# Themes # Themes

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@ -0,0 +1,286 @@
#!/bin/zsh
# _ssh_agent_plugin_debug function
function _ssh_agent_plugin_debug() {
local _ssh_agent_plugin_verbose
zstyle -b :xals:plugins:ssh-agent verbose _ssh_agent_plugin_verbose
if [[ "${_ssh_agent_plugin_verbose}" == "yes" ]]; then
echo $*
fi
}
# Function to clean global link
function _ssh_agent_plugin_clean_global_sock() {
# Clean link to obsolete auth socket.
if [ -L "${_ssh_agent_plugin_sock}" ]; then
_ssh_agent_plugin_debug "Found global link to socket, checking it."
if [ -S "${_ssh_agent_plugin_sock}" -a -w "${_ssh_agent_plugin_sock}" ]; then
_ssh_agent_plugin_debug "Global link relating to a valid socket, keeping it."
else
_ssh_agent_plugin_debug "Found a broken global link, removing it."
# Remove obsolete global link
unlink "${_ssh_agent_plugin_sock}"
fi
elif [ -e "${_ssh_agent_plugin_sock}" ]; then
# Note: here ${_ssh_agent_plugin_sock} may exist, but may be not a symlink, we remove it.
_ssh_agent_plugin_debug "Found garbage, cleaning up."
rm -f "${_ssh_agent_plugin_sock}"
fi
}
function _ssh_agent_plugin_clean_auth_sock() {
# Cleanup ${SSH_AUTH_SOCK} if not a valid socket.
if [ -S "${SSH_AUTH_SOCK}" -a -w "${SSH_AUTH_SOCK}" ]; then
_ssh_agent_plugin_debug "Auth socket is valid."
else
if [ -e "${SSH_AUTH_SOCK}" ]; then
_ssh_agent_plugin_debug "Found garbage, cleaning up."
rm -f "${SSH_AUTH_SOCK}"
fi
if [ -n "${SSH_AUTH_SOCK}" ]; then
_ssh_agent_plugin_debug "Found an invalid \${SSH_AUTH_SOCK}, unsetting it."
unset SSH_AUTH_SOCK
fi
fi
}
function _ssh_agent_plugin_launch_agent() {
if [ -S "${SSH_AUTH_SOCK}" ]; then
_ssh_agent_plugin_debug "Found valid \${SSH_AUTH_SOCK}."
else
# We don't have an SSH auth socket, we try to create one.
if [ -x "$(which keychain)" ]; then
_ssh_agent_plugin_debug "Launching keychain."
# Launch keychain
_ssh_agent_plugin_run_keychain
elif [ -x "$(which ssh-agent)" ]; then
_ssh_agent_plugin_debug "Lauching classic SSH agent."
_ssh_agent_plugin_run_classic_agent
else
_ssh_agent_plugin_debug "No valid SSH agent manager found."
fi
fi
}
function _ssh_agent_plugin_export_global_sock() {
# Export SSH authentication socket if socket is valid.
if [ -S "${_ssh_agent_plugin_sock}" -a -w "${_ssh_agent_plugin_sock}" ]; then
if [ "${_ssh_agent_plugin_sock}" != "${SSH_AUTH_SOCK}" ]; then
_ssh_agent_plugin_debug "Exporting ${_ssh_agent_plugin_sock} as new \${SSH_AUTH_SOCK}."
export SSH_AUTH_SOCK="${_ssh_agent_plugin_sock}"
else
_ssh_agent_plugin_debug "\${_ssh_agent_plugin_sock} is already the same as \${SSH_AUTH_SOCK}."
fi
else
_ssh_agent_plugin_debug "${_ssh_agent_plugin_sock} is not a valid socket."
fi
}
function _ssh_agent_plugin_link_global_sock() {
# Link to existing socket, if we are not already linked to it
if [ -S "${SSH_AUTH_SOCK}" -a -w "${SSH_AUTH_SOCK}" ]; then
_ssh_agent_plugin_debug "Found valid \${SSH_AUTH_SOCK}."
if [ "${SSH_AUTH_SOCK}" != "${_ssh_agent_plugin_sock}" ]; then
# Update link with new socket if needed
if [ -S "${SSH_AUTH_SOCK}" -a -w "${SSH_AUTH_SOCK}" ]; then
_ssh_agent_plugin_debug "Linking to new valid \${SSH_AUTH_SOCK}."
ln -sf "${SSH_AUTH_SOCK}" "${_ssh_agent_plugin_sock}"
else
_ssh_agent_plugin_debug "Don't have a valid \${SSH_AUTH_SOCK} to link to."
fi
else
_ssh_agent_plugin_debug "Already using linked socket."
fi
else
_ssh_agent_plugin_debug "Didn't find valid \${SSH_AUTH_SOCK} to link to."
fi
}
# launch SSH agent
function _ssh_agent_plugin_init() {
local -x _ssh_agent_plugin_sock
zstyle -s :xals:plugins:ssh-agent global_sock _ssh_agent_plugin_sock
local _ssh_agent_plugin_enable_root
zstyle -b :xals:plugins:ssh-agent enable_root _ssh_agent_plugin_enable_root
local -x _ssh_agent_plugin_directory="$HOME/.ssh"
if [ ! -d "${_ssh_agent_plugin_directory}" ]; then
_ssh_agent_plugin_debug "Creating ${_ssh_agent_plugin_directory} directory."
mkdir "${_ssh_agent_plugin_directory}"
chmod 700 "${_ssh_agent_plugin_directory}"
fi
# Reuse user authentication socket if I am root and using sudo.
if [ -z "${_ssh_agent_plugin_sock}" ]; then
if [ "${USER}" != "root" ]; then
_ssh_agent_plugin_sock="/tmp/ssh-agent-$USER"
elif [ "${_ssh_agent_plugin_enable_root}" == "yes" ]; then
if [ -n "${SUDO_USER}" ]; then
_ssh_agent_plugin_sock="/tmp/ssh-agent-$SUDO_USER"
else
_ssh_agent_plugin_sock="/tmp/ssh-agent-$USER"
fi
fi
fi
_ssh_agent_plugin_debug "Static socket will be: \"${_ssh_agent_plugin_sock}\"."
# We want to do socket linking only if it is necessary
if [ -n "${_ssh_agent_plugin_sock}" ]; then
_ssh_agent_plugin_debug "Global socket is defined"
# Clean global link.
_ssh_agent_plugin_clean_global_sock
# Clean auth sock.
_ssh_agent_plugin_clean_auth_sock
# First time export.
_ssh_agent_plugin_export_global_sock
# Launch agent if not valid SSH_AUTH_SOCK found.
_ssh_agent_plugin_launch_agent
# Link to SSH_AUTH_SOCK.
_ssh_agent_plugin_link_global_sock
# Second time export.
_ssh_agent_plugin_export_global_sock
# Add identities.
_ssh_agent_plugin_add_identities
fi
}
# Use keychain to launch SSH agent.
function _ssh_agent_plugin_run_keychain() {
if [ -x "$(which keychain)" ]; then
keychain --quiet --nogui --inherit any --agents ssh
[ -r $HOME/.keychain/$(hostname)-sh ] && source $HOME/.keychain/$(hostname)-sh
fi
}
# Launch classic SSH agent.
function _ssh_agent_plugin_run_classic_agent() {
# We launch the agent only if there is not auth socket.
if [ -S "${SSH_AUTH_SOCK}" -a -w "${SSH_AUTH_SOCK}" ]; then
# We should not be here, but just in case...
else
if [ -e "${SSH_AUTH_SOCK}" ]; then
# Should not happen... Just in case...
rm -f "${SSH_AUTH_SOCK}"
fi
if [ -x "$(which ssh-agent)" ]; then
local _ssh_agent_plugin_pidfile="${_ssh_agent_plugin_directory}/agent-pid"
# Cleanup old PID file
if [ -r "${_ssh_agent_plugin_pidfile}" ]; then
local _ssh_agent_plugin_pid=$(< "${_ssh_agent_plugin_pidfile}")
_ssh_agent_plugin_debug "Found a PID file with value ${_ssh_agent_plugin_pid}."
if [ ! -e "${_ssh_agent_plugin_pid}" ] ; then
_ssh_agent_plugin_debug "Removing remaining PID file."
rm -f "${_ssh_agent_plugin_pidfile}"
fi
fi
if [ -r "${_ssh_agent_plugin_pidfile}" ]; then
_ssh_agent_plugin_debug "Killing existing agent."
export SSH_AGENT_PID=$(< "${_ssh_agent_plugin_pidfile}")
eval $(ssh-agent -s -k) > /dev/null
rm -f "${_ssh_agent_plugin_pidfile}"
fi
_ssh_agent_plugin_debug "Launching SSH agent."
local _ssh_agent_plugin_lifetime
zstyle -s :xals:plugins:ssh-agent lifetime _ssh_agent_plugin_lifetime
eval $(ssh-agent -s ${_ssh_agent_plugin_lifetime:+-t} ${_ssh_agent_plugin_lifetime}) > /dev/null
echo $SSH_AGENT_PID > "${_ssh_agent_plugin_pidfile}"
fi
fi
}
# Add SSH key if not already added.
function _ssh_agent_plugin_add_identities() {
if [ -x "$(which ssh-add)" ]; then
# "ssh-add -l" return codes:
# 0: one or more keys were found.
# 1: no key was found.
# 2: agent could not be contacted.
local _ssh_agent_plugin_identities
zstyle -a :xals:plugins:ssh-agent identities _ssh_agent_plugin_identities
if [ "${#_ssh_agent_plugin_identities}" -eq 0 ]; then
_ssh_agent_plugin_identities=("id_rsa")
fi
ssh-add -l > /dev/null
if [ 2 -eq $? ] ; then
# Agent is not launched
_ssh_agent_plugin_debug "Agent is not launched. Probably no key available."
else
# Agent has identities added, check if the ones we want are present, add them if not.
local _ssh_agent_plugin_identity
for _ssh_agent_plugin_identity in ${_ssh_agent_plugin_identities}; do
local _ssh_agent_plugin_identity_absolute_path
_ssh_agent_plugin_identity_absolute_path=$(readlink -f "${_ssh_agent_plugin_directory}/${_ssh_agent_plugin_identity}")
if [ -r "${_ssh_agent_plugin_identity_absolute_path}" ]; then
ssh-add -l | awk '{print $3}' | xargs -n 1 readlink -f | grep -q "${_ssh_agent_plugin_identity_absolute_path}"
if [ $? -ne 0 ]; then
_ssh_agent_plugin_debug "Adding ${_ssh_agent_plugin_identity} identity."
ssh-add "${_ssh_agent_plugin_identity_absolute_path}"
else
_ssh_agent_plugin_debug "${_ssh_agent_plugin_identity} identity already added."
fi
else
_ssh_agent_plugin_debug "${_ssh_agent_plugin_identity} identity does not exist."
fi
done
fi
fi
}
_ssh_agent_plugin_init
unfunction _ssh_agent_plugin_init
unfunction _ssh_agent_plugin_clean_global_sock
unfunction _ssh_agent_plugin_clean_auth_sock
unfunction _ssh_agent_plugin_export_global_sock
unfunction _ssh_agent_plugin_launch_agent
unfunction _ssh_agent_plugin_link_global_sock
unfunction _ssh_agent_plugin_run_keychain
unfunction _ssh_agent_plugin_run_classic_agent
unfunction _ssh_agent_plugin_add_identities
unfunction _ssh_agent_plugin_debug