1 files changed, 82 insertions, 0 deletions
diff --git a/Shell/ssh-agent.plugin.zsh b/Shell/ssh-agent.plugin.zsh
new file mode 100644
index 0000000..313fe77
--- /dev/null
+++ b/Shell/ssh-agent.plugin.zsh
@@ -0,0 +1,82 @@
+typeset _agent_forwarding _ssh_env_cache
+
+function _start_agent() {
+	local lifetime
+	zstyle -s :omz:plugins:ssh-agent lifetime lifetime
+
+	# start ssh-agent and setup environment
+	echo Starting ssh-agent...
+	ssh-agent -s ${lifetime:+-t} ${lifetime} | sed 's/^echo/#echo/' >! $_ssh_env_cache
+	chmod 600 $_ssh_env_cache
+	. $_ssh_env_cache > /dev/null
+}
+
+function _add_identities() {
+	local id line sig lines
+	local -a identities loaded_sigs loaded_ids not_loaded
+	zstyle -a :omz:plugins:ssh-agent identities identities
+
+	# check for .ssh folder presence
+	if [[ ! -d $HOME/.ssh ]]; then
+		return
+	fi
+
+	# add default keys if no identities were set up via zstyle
+	# this is to mimic the call to ssh-add with no identities
+	if [[ ${#identities} -eq 0 ]]; then
+		# key list found on `ssh-add` man page's DESCRIPTION section
+		for id in id_rsa id_dsa id_ecdsa id_ed25519 identity id_rsa_work; do
+			# check if file exists
+			[[ -f "$HOME/.ssh/$id" ]] && identities+=$id
+		done
+	fi
+
+	# get list of loaded identities' signatures and filenames
+	if lines=$(ssh-add -l); then
+		for line in ${(f)lines}; do
+			loaded_sigs+=${${(z)line}[2]}
+			loaded_ids+=${${(z)line}[3]}
+		done
+	fi
+
+	# add identities if not already loaded
+	for id in $identities; do
+		# check for filename match, otherwise try for signature match
+		if [[ ${loaded_ids[(I)$HOME/.ssh/$id]} -le 0 ]]; then
+			sig="$(ssh-keygen -lf "$HOME/.ssh/$id" | awk '{print $2}')"
+			[[ ${loaded_sigs[(I)$sig]} -le 0 ]] && not_loaded+="$HOME/.ssh/$id"
+		fi
+	done
+
+	[[ -n "$not_loaded" ]] && ssh-add ${^not_loaded}
+}
+
+# Get the filename to store/lookup the environment from
+_ssh_env_cache="$HOME/.ssh/environment-$SHORT_HOST"
+
+# test if agent-forwarding is enabled
+zstyle -b :omz:plugins:ssh-agent agent-forwarding _agent_forwarding
+
+if [[ $_agent_forwarding == "yes" && -n "$SSH_AUTH_SOCK" ]]; then
+	# Add a nifty symlink for screen/tmux if agent forwarding
+	[[ -L $SSH_AUTH_SOCK ]] || ln -sf "$SSH_AUTH_SOCK" /tmp/ssh-agent-$USER-screen
+elif [[ -f "$_ssh_env_cache" ]]; then
+	# Source SSH settings, if applicable
+	. $_ssh_env_cache > /dev/null
+	if [[ $USER == "root" ]]; then
+		FILTER="ax"
+	else
+		FILTER="x"
+	fi
+	ps $FILTER | grep ssh-agent | grep -q $SSH_AGENT_PID || {
+		_start_agent
+	}
+else
+	_start_agent
+fi
+
+_add_identities
+
+# tidy up after ourselves
+unset _agent_forwarding _ssh_env_cache
+unfunction _start_agent _add_identities