server-scripts/scripts/usr/local/bin/script-files-permissions-set

#!/usr/bin/env bash
# Intelligently change permissions on selected directories
# Copyright 2021-2025 Bryan C. Roessler
# Licensed under the Apache License, Version 2.0
p="${BASH_SOURCE[0]%/*}"; [[ -r $p/script-functions ]] && . "$p"/script-functions || exit 1

is_root

if [[ $# -eq 0 ]]; then
    echo "No arguments provided, using autodetection"
    paths=("$PWD")
    user=$(stat -c "%U" "$PWD")
    group=$(stat -c "%G" "$PWD")
elif [[ $# -eq 1 ]]; then
    user="$1"
    group="$1"
    paths=("$PWD")
elif [[ $# -eq 2 ]]; then
    user="$1"
    group="$2"
    paths=("$PWD")
elif [[ $# -gt 2 ]]; then
    user="$1"
    group="$2"
    paths=("${@:3}")
fi

for path in "${paths[@]}"; do 
    if [[ "$path" == "/" ]]; then
        echo "You are trying to operate on the root partition!"
        echo "This seems highly unusual!"
        ask_ok "Continue?" || exit $?
    fi
    og_user=$(stat -c "%U" "$path")
    og_group=$(stat -c "%G" "$path")
    printf "%-20s %-10s %-10s\n" "PATH" "USER" "GROUP"
    echo -e "$path\t$og_user\t$og_group"
    if [[ "$group" != "smbgrp" || "$og_group" != "smbgrp" ]]; then
        echo "$path is not world accessible by the smbgrp group"
        ask_ok "Change $path group $og_group to smbgrp?" && group="smbgrp"
    fi
done

ask_ok "Apply user: $user and group: $group to ${paths[*]} and all subdirs?" && \
    chown -R "$user":"$group" "${paths[@]}"

# Set mode based on group:
# - 6775: Enables read/write/execute for owner and group, with setgid bit for group inheritance.
# - 755: Enables read/write/execute for owner, and read/execute for group and others.
[[ "$group" == "smbgrp" ]] && mode=6775 || mode=755
    
ask_ok "Apply chmod $mode to ${paths[*]} and all subdirs?" && \
    chmod -R "$mode" "${paths[@]}"

# Let's do it in less steps (see above) for now unless it becomes a problem
# TODO: Implement setuid/setgid functionality to ensure files and directories inherit user/group permissions.
# echo "Apply setuid/setgid bits to ${paths[*]} and all subdirs?"
# ask_ok "Files/dirs will inherit their " && \
#     chmod -R g+s,u+s "${paths[@]}"