pppossh: new package for network proto "pppossh"

Signed-off-by: Yousong Zhou <yszhou4tech@gmail.com>

net/pppossh/files/pppossh.sh

@@ -0,0 +1,72 @@
+#!/bin/sh
+
+SSH=/usr/bin/ssh
+[ -x "$SSH" ] || {
+	echo "Cannot find executable $SSH." >&2
+	exit 1
+}
+
+. /lib/functions.sh
+. ../netifd-proto.sh
+init_proto "$@"
+
+INCLUDE_ONLY=1
+
+. ./ppp.sh
+
+proto_pppossh_init_config() {
+	ppp_generic_init_config
+	config_add_string server sshuser ipaddr peeraddr ssh_options
+	config_add_array 'identity:list(string)'
+	config_add_int port use_hostdep
+	available=1
+	no_device=1
+}
+
+proto_pppossh_setup() {
+	local config="$1"
+	local iface="$2"
+	local user="$(id -nu)"
+	local home=$(sh -c "echo ~$user")
+	local server port sshuser ipaddr peeraddr ssh_options identity use_hostdep
+	local ip fn errmsg opts pty
+
+	json_get_vars port sshuser ipaddr peeraddr ssh_options use_hostdep
+	json_get_var server server && {
+		[ -z "$use_hostdep" ] && use_hostdep=1
+		for ip in $(resolveip -t 5 "$server"); do
+			if [ "$use_hostdep" -gt 0 ]; then
+				( proto_add_host_dependency "$config" "$ip" )
+			else
+				break
+			fi
+		done
+	}
+	[ -n "$ip" ] || errmsg="${errmsg}Could not resolve $server\n"
+	[ -n "$sshuser" ] || errmsg="${errmsg}Missing sshuser option\n"
+
+	json_get_values identity identity
+	[ -z "$identity" ] && identity="'$home/.ssh/id_rsa' '$home/.ssh/id_dsa'"
+	for fn in $identity; do
+		[ -f "$fn" ] && opts="$opts -i $fn"
+	done
+	[ -n "$opts" ] || errmsg="${errmsg}Cannot find valid identity file\n"
+
+	[ -n "$errmsg" ] && {
+		echo -ne "$errmsg" >&2
+		proto_setup_failed "$config"
+		exit 1
+	}
+	opts="$opts ${port:+-p $port}"
+	opts="$opts ${ssh_options}"
+	opts="$opts $sshuser@$server"
+	pty="env 'HOME=$home' "$SSH" $opts pppd nodetach notty noauth"
+
+	ppp_generic_setup "$config" noauth pty "$pty" "$ipaddr:$peeraddr"
+}
+
+proto_pppossh_teardown() {
+	ppp_generic_teardown "$@"
+}
+
+add_protocol pppossh