nixos-rebuild: support sudo + --target-host

This adds support for deploying to remote hosts without being root:

  sudo nixos-rebuild --target-host non-root@host

Without this change, only root@host is able to deploy.

The idea is that if the local command is run with sudo, so should the
remote one, thus there is no need for adding any CLI options.

1 files changed, 7 insertions, 3 deletions

diff --git a/nixos/modules/installer/tools/nixos-rebuild.sh b/nixos/modules/installer/tools/nixos-rebuild.sh
index ea434ca8741..891f374df53 100644
--- a/nixos/modules/installer/tools/nixos-rebuild.sh
+++ b/nixos/modules/installer/tools/nixos-rebuild.sh
@@ -22,6 +22,7 @@ repair=
 profile=/nix/var/nix/profiles/system
 buildHost=
 targetHost=
+maybeSudo=
 
 while [ "$#" -gt 0 ]; do
     i="$1"; shift 1
@@ -96,6 +97,9 @@ while [ "$#" -gt 0 ]; do
     esac
 done
 
+if [ -n "$SUDO_USER" ]; then
+    maybeSudo="sudo "
+fi
 
 if [ -z "$buildHost" -a -n "$targetHost" ]; then
     buildHost="$targetHost"
@@ -111,9 +115,9 @@ buildHostCmd() {
     if [ -z "$buildHost" ]; then
         "$@"
     elif [ -n "$remoteNix" ]; then
-        ssh $SSHOPTS "$buildHost" env PATH="$remoteNix:$PATH" "$@"
+        ssh $SSHOPTS "$buildHost" env PATH="$remoteNix:$PATH" "$maybeSudo$@"
     else
-        ssh $SSHOPTS "$buildHost" "$@"
+        ssh $SSHOPTS "$buildHost" "$maybeSudo$@"
     fi
 }
 
@@ -121,7 +125,7 @@ targetHostCmd() {
     if [ -z "$targetHost" ]; then
         "$@"
     else
-        ssh $SSHOPTS "$targetHost" "$@"
+        ssh $SSHOPTS "$targetHost" "$maybeSudo$@"
     fi
 }