include/ssh: Simplify SSH module API

The ssh_tunnel_close() and ssh_proxy_close() functions do essentially
the same thing, so they should be merged into one. Further, both of
the functions require the user to remember multiple values from the
ssh_*_open() call in order to close the connection. This seems
unnecessarily complicated.
This commit adds the ssh_close() function as a replacement for
ssh_tunnel_close() and ssh_proxy_close(). Further, the ssh_*_open()
functions now return a handle that can be passed to ssh_close() to
close the respective connection.

diff --git a/include/ssh.sh b/include/ssh.sh
index fe1d32c42101a2b3db84addd114fc285577ae3c6..a452a7ba9a6cbcd809881fee152e29fef1e3324e 100644 (file)
--- a/include/ssh.sh
+++ b/include/ssh.sh
@@ -56,100 +56,131 @@ _ssh_proxy_ctrl_socket_name() {
        return 0
 }
 
-ssh_tunnel_open() {
-       local tunnel_host
-       local tunnel_user
-       local remote_addr
-       local remote_port
-       local local_addr
-       local local_port
-
-       tunnel_host="$1"
-       tunnel_user="$2"
-       remote_addr="$3"
-        remote_port="$4"
-       local_addr="$5"
-       local_port="$6"
+_ssh_make_handle() {
+       local ctrlsock="$1"
+       local hostspec="$2"
 
-       local ctrl_sock
-       local addrspec
-       local sshtarget
+       local handle
 
-       if ! ctrl_sock=$(_ssh_tunnel_ctrl_socket_name "$remote_addr" \
-                                                     "$remote_port" \
-                                                     "$local_port"); then
+       if ! handle=$(base64 <<< "$ctrlsock" 2>/dev/null); then
                return 1
        fi
 
-       addrspec="$local_addr:$local_port:$remote_addr:$remote_port"
-       sshtarget="$tunnel_user@$tunnel_host"
+       handle+=":"
 
-       if ! ssh -M -S "$ctrl_sock" -fnNT -o "ExitOnForwardFailure=yes" \
-            -L "$addrspec" "$sshtarget" > /dev/null; then
+       if ! handle+=$(base64 <<< "$hostspec" 2>/dev/null); then
+               return 1
+       fi
+
+       echo "$handle"
+       return 0
+}
+
+_ssh_handle_get_ctrlsock() {
+       local handle="$1"
+
+       local ctrlsock
+
+       if ! ctrlsock=$(base64 -d <<< "${handle%%:*}" 2>/dev/null); then
+               return 1
+       fi
+
+       echo "$ctrlsock"
+       return 0
+}
+
+_ssh_handle_get_hostspec() {
+       local handle="$1"
+
+       local hostspec
+
+       if ! hostspec=$(base64 -d <<< "${handle##*:}" 2>/dev/null); then
                return 1
        fi
 
-       echo "$ctrl_sock"
+       echo "$hostspec"
        return 0
 }
 
-ssh_tunnel_close() {
-       local tunnel_host
-       local tunnel_user
+ssh_tunnel_open() {
+       local tunnel_host="$1"
+       local tunnel_user="$2"
+       local remote_addr="$3"
+       local remote_port="$4"
+       local local_addr="$5"
+       local local_port="$6"
+
        local ctrl_sock
+       local addrspec
+       local sshtarget
+       local handle
+
+       addrspec="$local_addr:$local_port:$remote_addr:$remote_port"
+       sshtarget="$tunnel_user@$tunnel_host"
 
-       tunnel_host="$1"
-       tunnel_user="$2"
-       ctrl_sock="$3"
+       if ! ctrl_sock=$(_ssh_tunnel_ctrl_socket_name "$remote_addr" \
+                                                     "$remote_port" \
+                                                     "$local_port"); then
+               return 1
+       fi
 
-       if ! ssh -S "$ctrl_sock" -O exit "$tunnel_user@$tunnel_host" &> /dev/null; then
+       if ! handle=$(_ssh_make_handle "$ctrl_sock" "$sshtarget"); then
                return 1
        fi
 
+       if ! ssh -M -S "$ctrl_sock" -fnNT -o "ExitOnForwardFailure=yes" \
+            -L "$addrspec" "$sshtarget" > /dev/null; then
+               return 1
+       fi
+
+       echo "$handle"
        return 0
 }
 
 ssh_proxy_open() {
-       local proxy_host
-       local proxy_user
-       local local_addr
-       local local_port
+       local proxy_host="$1"
+       local proxy_user="$2"
+       local local_addr="$3"
+       local local_port="$4"
 
        local ctrl_sock
        local addrspec
        local sshtarget
+       local handle
 
-       proxy_host="$1"
-       proxy_user="$2"
-       local_addr="$3"
-       local_port="$4"
+       addrspec="$local_addr:$local_port"
+       sshtarget="$proxy_user@$proxy_host"
 
        if ! ctrl_sock=$(_ssh_proxy_ctrl_socket_name "$local_addr" "$local_port"); then
                return 1
        fi
 
-       addrspec="$local_addr:$local_port"
-       sshtarget="$proxy_user@$proxy_host"
+       if ! handle=$(_ssh_make_handle "$ctrl_sock" "$sshtarget"); then
+               return 1
+       fi
 
        if ! ssh -M -S "$ctrl_sock" -fnNT -o "ExitOnForwardFailure=yes" \
             -D "$addrspec" "$sshtarget" > /dev/null; then
                return 1
        fi
 
-       echo "$ctrl_sock"
+       echo "$handle"
        return 0
 }
 
-ssh_proxy_close() {
-       local proxy_host
-       local proxy_user
-       local ctrl_sock
+ssh_close() {
+       local handle="$1"
 
-       proxy_host="$1"
-       proxy_user="$2"
-       ctrl_sock="$3"
+       local ctrlsock
+       local hostspec
+
+       if ! ctrlsock=$(_ssh_handle_get_ctrlsock "$handle") ||
+          ! hostspec=$(_ssh_handle_get_hostspec "$handle"); then
+               log_error "Invalid handle"
+               return 1
+       fi
 
-       if ! ssh -S "$ctrl_sock" -O exit "$proxy_user@$proxy_host" &> /dev/null; then
+       if ! ssh -S "$ctrlsock" -O exit "$hostspec" &> /dev/null; then
                return 1
        fi