Manage file and folder permissions across your MacFleet devices using command-line tools. This tutorial covers permission models, ownership management, access control implementation, and enterprise-wide permission policy deployment.

Understanding macOS Permission System

macOS uses a Unix-based permission system with three types of permissions and three user categories:

Permission Types

• Read (r) - View file contents or list directory contents
• Write (w) - Modify file contents or create/delete files in directory
• Execute (x) - Run file as program or access directory

User Categories

• Owner (u) - The user who created the file/folder
• Group (g) - Users belonging to the file's group
• Others (o) - All other system users

Permission Representations

Basic Permission Management

View File/Folder Permissions

#!/bin/bash

# View permissions for specific file or folder
TARGET_PATH="$1"

if [[ -z "$TARGET_PATH" ]]; then
    echo "❌ Please specify a file or folder path"
    echo "Usage: $0 /path/to/file/or/folder"
    exit 1
fi

if [[ ! -e "$TARGET_PATH" ]]; then
    echo "❌ Path does not exist: $TARGET_PATH"
    exit 1
fi

echo "📋 Permission details for: $TARGET_PATH"
ls -la "$TARGET_PATH"

echo ""
echo "📊 Detailed permission breakdown:"
ls -la "$TARGET_PATH" | while read -r line; do
    if [[ "$line" != total* ]]; then
        echo "Full output: $line"
        
        # Extract permission string
        perms=$(echo "$line" | awk '{print $1}')
        if [[ ${#perms} -eq 10 ]]; then
            echo "File type: ${perms:0:1}"
            echo "Owner permissions: ${perms:1:3}"
            echo "Group permissions: ${perms:4:3}"
            echo "Others permissions: ${perms:7:3}"
        fi
    fi
done

Set Permissions Using Octal Notation

#!/bin/bash

# Set permissions using octal notation (e.g., 755, 644)
TARGET_PATH="$1"
PERMISSION="$2"

if [[ -z "$TARGET_PATH" || -z "$PERMISSION" ]]; then
    echo "❌ Please specify path and permission"
    echo "Usage: $0 /path/to/file 755"
    echo "Common permissions:"
    echo "  755 - rwxr-xr-x (owner: full, group/others: read+execute)"
    echo "  644 - rw-r--r-- (owner: read+write, group/others: read-only)"
    echo "  600 - rw------- (owner: read+write, group/others: no access)"
    exit 1
fi

if [[ ! -e "$TARGET_PATH" ]]; then
    echo "❌ Path does not exist: $TARGET_PATH"
    exit 1
fi

# Validate permission format
if [[ ! "$PERMISSION" =~ ^[0-7]{3}$ ]]; then
    echo "❌ Invalid permission format. Use 3-digit octal (e.g., 755)"
    exit 1
fi

echo "🔧 Setting permissions $PERMISSION on: $TARGET_PATH"

# Show current permissions
echo "Current permissions:"
ls -la "$TARGET_PATH"

# Apply new permissions
if chmod "$PERMISSION" "$TARGET_PATH"; then
    echo "✅ Permissions updated successfully"
    
    echo "New permissions:"
    ls -la "$TARGET_PATH"
else
    echo "❌ Failed to set permissions"
    exit 1
fi

Set Permissions Using Symbolic Notation

#!/bin/bash

# Set permissions using symbolic notation (e.g., u=rwx,g=rx,o=r)
TARGET_PATH="$1"
PERMISSION="$2"

if [[ -z "$TARGET_PATH" || -z "$PERMISSION" ]]; then
    echo "❌ Please specify path and permission"
    echo "Usage: $0 /path/to/file 'u=rwx,g=rx,o=r'"
    echo "Symbolic notation examples:"
    echo "  u=rwx,g=rx,o=rx  - Owner: full, Group/Others: read+execute"
    echo "  u=rw,g=r,o=r     - Owner: read+write, Group/Others: read-only"
    echo "  u=rw,g=,o=       - Owner: read+write, Group/Others: no access"
    exit 1
fi

if [[ ! -e "$TARGET_PATH" ]]; then
    echo "❌ Path does not exist: $TARGET_PATH"
    exit 1
fi

echo "🔧 Setting permissions '$PERMISSION' on: $TARGET_PATH"

# Show current permissions
echo "Current permissions:"
ls -la "$TARGET_PATH"

# Apply new permissions
if chmod "$PERMISSION" "$TARGET_PATH"; then
    echo "✅ Permissions updated successfully"
    
    echo "New permissions:"
    ls -la "$TARGET_PATH"
else
    echo "❌ Failed to set permissions"
    exit 1
fi

Ownership Management

Change File/Folder Owner

#!/bin/bash

# Change ownership of file or folder
TARGET_PATH="$1"
NEW_OWNER="$2"

if [[ -z "$TARGET_PATH" || -z "$NEW_OWNER" ]]; then
    echo "❌ Please specify path and new owner"
    echo "Usage: $0 /path/to/file username"
    exit 1
fi

if [[ ! -e "$TARGET_PATH" ]]; then
    echo "❌ Path does not exist: $TARGET_PATH"
    exit 1
fi

# Verify user exists
if ! id "$NEW_OWNER" &>/dev/null; then
    echo "❌ User does not exist: $NEW_OWNER"
    echo "Available users:"
    dscl . list /Users | grep -v "^_"
    exit 1
fi

echo "👤 Changing owner of '$TARGET_PATH' to: $NEW_OWNER"

# Show current ownership
echo "Current ownership:"
ls -la "$TARGET_PATH"

# Change ownership
if sudo chown "$NEW_OWNER" "$TARGET_PATH"; then
    echo "✅ Ownership changed successfully"
    
    echo "New ownership:"
    ls -la "$TARGET_PATH"
else
    echo "❌ Failed to change ownership"
    exit 1
fi

Change File/Folder Group

#!/bin/bash

# Change group ownership of file or folder
TARGET_PATH="$1"
NEW_GROUP="$2"

if [[ -z "$TARGET_PATH" || -z "$NEW_GROUP" ]]; then
    echo "❌ Please specify path and new group"
    echo "Usage: $0 /path/to/file groupname"
    echo "Common groups: admin, staff, wheel, everyone"
    exit 1
fi

if [[ ! -e "$TARGET_PATH" ]]; then
    echo "❌ Path does not exist: $TARGET_PATH"
    exit 1
fi

# Verify group exists
if ! dscl . read /Groups/"$NEW_GROUP" &>/dev/null; then
    echo "❌ Group does not exist: $NEW_GROUP"
    echo "Available groups:"
    dscl . list /Groups | grep -v "^_"
    exit 1
fi

echo "👥 Changing group of '$TARGET_PATH' to: $NEW_GROUP"

# Show current ownership
echo "Current ownership:"
ls -la "$TARGET_PATH"

# Change group ownership
if sudo chgrp "$NEW_GROUP" "$TARGET_PATH"; then
    echo "✅ Group ownership changed successfully"
    
    echo "New ownership:"
    ls -la "$TARGET_PATH"
else
    echo "❌ Failed to change group ownership"
    exit 1
fi

Recursive Permission Management

Set Permissions Recursively

#!/bin/bash

# Set permissions recursively on directory and all contents
TARGET_DIR="$1"
DIR_PERMISSION="$2"
FILE_PERMISSION="$3"

if [[ -z "$TARGET_DIR" || -z "$DIR_PERMISSION" || -z "$FILE_PERMISSION" ]]; then
    echo "❌ Please specify directory path and permissions"
    echo "Usage: $0 /path/to/directory 755 644"
    echo "This will set directories to 755 and files to 644"
    exit 1
fi

if [[ ! -d "$TARGET_DIR" ]]; then
    echo "❌ Directory does not exist: $TARGET_DIR"
    exit 1
fi

echo "🔄 Setting recursive permissions on: $TARGET_DIR"
echo "Directories will be set to: $DIR_PERMISSION"
echo "Files will be set to: $FILE_PERMISSION"

# Count items to process
dir_count=$(find "$TARGET_DIR" -type d | wc -l)
file_count=$(find "$TARGET_DIR" -type f | wc -l)

echo "Found $dir_count directories and $file_count files to process"

read -p "Continue? (y/N): " -n 1 -r
echo
if [[ ! $REPLY =~ ^[Yy]$ ]]; then
    echo "Operation cancelled"
    exit 0
fi

# Set permissions on directories
echo "🗂️ Setting directory permissions..."
if find "$TARGET_DIR" -type d -exec chmod "$DIR_PERMISSION" {} \;; then
    echo "✅ Directory permissions set successfully"
else
    echo "❌ Failed to set directory permissions"
    exit 1
fi

# Set permissions on files
echo "📄 Setting file permissions..."
if find "$TARGET_DIR" -type f -exec chmod "$FILE_PERMISSION" {} \;; then
    echo "✅ File permissions set successfully"
else
    echo "❌ Failed to set file permissions"
    exit 1
fi

echo "✅ Recursive permission update completed"

Enterprise Permission Management Script

#!/bin/bash

# MacFleet Permission Management Tool
# Comprehensive file and folder permission management for enterprise environments

# Configuration
LOG_FILE="/var/log/macfleet_permissions.log"
BACKUP_DIR="/var/backups/macfleet/permissions"
POLICY_FILE="/etc/macfleet/permission_policies.conf"
REPORT_DIR="/var/reports/macfleet/permissions"

# Logging function
log_action() {
    echo "$(date '+%Y-%m-%d %H:%M:%S') - $1" | tee -a "$LOG_FILE"
}

# Setup directories
setup_directories() {
    for dir in "$BACKUP_DIR" "$REPORT_DIR" "$(dirname "$POLICY_FILE")"; do
        if [[ ! -d "$dir" ]]; then
            sudo mkdir -p "$dir"
            log_action "Created directory: $dir"
        fi
    done
}

# Create permission backup
create_permission_backup() {
    local target_path="$1"
    local backup_file="$BACKUP_DIR/permissions_$(basename "$target_path")_$(date +%Y%m%d_%H%M%S).txt"
    
    echo "📦 Creating permission backup for: $target_path"
    
    if [[ -d "$target_path" ]]; then
        # Backup directory permissions recursively
        find "$target_path" -exec ls -la {} \; > "$backup_file" 2>/dev/null
    else
        # Backup single file permissions
        ls -la "$target_path" > "$backup_file" 2>/dev/null
    fi
    
    if [[ $? -eq 0 ]]; then
        echo "✅ Backup created: $backup_file"
        log_action "Permission backup created: $backup_file"
    else
        echo "⚠️ Warning: Could not create backup"
        log_action "Warning: Backup creation failed for $target_path"
    fi
}

# Apply enterprise permission policy
apply_enterprise_policy() {
    local policy_name="$1"
    
    echo "🏢 Applying enterprise permission policy: $policy_name"
    log_action "Starting enterprise policy application: $policy_name"
    
    case "$policy_name" in
        "secure_documents")
            apply_secure_documents_policy
            ;;
        "shared_workspace")
            apply_shared_workspace_policy
            ;;
        "application_deployment")
            apply_application_deployment_policy
            ;;
        "system_hardening")
            apply_system_hardening_policy
            ;;
        *)
            echo "❌ Unknown policy: $policy_name"
            return 1
            ;;
    esac
}

# Secure documents policy
apply_secure_documents_policy() {
    echo "🔒 Applying secure documents permission policy..."
    
    local secure_dirs=(
        "/Users/Shared/SecureDocuments"
        "/opt/macfleet/confidential"
        "/var/secure"
    )
    
    for dir in "${secure_dirs[@]}"; do
        if [[ -d "$dir" ]]; then
            echo "Securing directory: $dir"
            
            # Create backup
            create_permission_backup "$dir"
            
            # Apply secure permissions (owner: full, group: read, others: none)
            sudo find "$dir" -type d -exec chmod 750 {} \;
            sudo find "$dir" -type f -exec chmod 640 {} \;
            
            # Set admin group ownership
            sudo chgrp -R admin "$dir"
            
            log_action "Secure permissions applied to: $dir"
        fi
    done
}

# Shared workspace policy
apply_shared_workspace_policy() {
    echo "👥 Applying shared workspace permission policy..."
    
    local shared_dirs=(
        "/Users/Shared/TeamWork"
        "/opt/macfleet/shared"
        "/var/shared"
    )
    
    for dir in "${shared_dirs[@]}"; do
        if [[ -d "$dir" ]]; then
            echo "Configuring shared directory: $dir"
            
            # Create backup
            create_permission_backup "$dir"
            
            # Apply shared permissions (owner: full, group: full, others: read)
            sudo find "$dir" -type d -exec chmod 775 {} \;
            sudo find "$dir" -type f -exec chmod 664 {} \;
            
            # Set staff group ownership
            sudo chgrp -R staff "$dir"
            
            log_action "Shared permissions applied to: $dir"
        fi
    done
}

# Application deployment policy
apply_application_deployment_policy() {
    echo "📱 Applying application deployment permission policy..."
    
    local app_dirs=(
        "/Applications"
        "/opt/macfleet/applications"
        "/usr/local/bin"
    )
    
    for dir in "${app_dirs[@]}"; do
        if [[ -d "$dir" ]]; then
            echo "Securing application directory: $dir"
            
            # Create backup
            create_permission_backup "$dir"
            
            # Apply application permissions (owner: full, group/others: read+execute)
            sudo find "$dir" -type d -exec chmod 755 {} \;
            sudo find "$dir" -type f -name "*.app" -exec chmod 755 {} \;
            sudo find "$dir" -type f ! -name "*.app" -exec chmod 644 {} \;
            
            # Set admin ownership
            sudo chown -R root:admin "$dir"
            
            log_action "Application permissions applied to: $dir"
        fi
    done
}

# System hardening policy
apply_system_hardening_policy() {
    echo "🛡️ Applying system hardening permission policy..."
    
    local system_dirs=(
        "/etc"
        "/var/log"
        "/usr/bin"
        "/usr/sbin"
    )
    
    for dir in "${system_dirs[@]}"; do
        if [[ -d "$dir" ]]; then
            echo "Hardening system directory: $dir"
            
            # Create backup
            create_permission_backup "$dir"
            
            # Apply restrictive permissions
            case "$dir" in
                "/etc")
                    sudo find "$dir" -type f -exec chmod 644 {} \;
                    sudo find "$dir" -type d -exec chmod 755 {} \;
                    ;;
                "/var/log")
                    sudo find "$dir" -type f -exec chmod 640 {} \;
                    sudo find "$dir" -type d -exec chmod 750 {} \;
                    ;;
                "/usr/bin"|"/usr/sbin")
                    sudo find "$dir" -type f -exec chmod 755 {} \;
                    sudo find "$dir" -type d -exec chmod 755 {} \;
                    ;;
            esac
            
            # Ensure root ownership
            sudo chown -R root:wheel "$dir"
            
            log_action "System hardening applied to: $dir"
        fi
    done
}

# Audit permission compliance
audit_permissions() {
    local target_path="$1"
    local audit_file="$REPORT_DIR/permission_audit_$(date +%Y%m%d_%H%M%S).txt"
    
    echo "🔍 Auditing permissions for: $target_path"
    
    {
        echo "MacFleet Permission Audit Report"
        echo "Generated: $(date)"
        echo "Target: $target_path"
        echo "Host: $(hostname)"
        echo "=================================="
        echo ""
        
        if [[ -d "$target_path" ]]; then
            echo "=== Directory Structure and Permissions ==="
            find "$target_path" -exec ls -la {} \; 2>/dev/null
            echo ""
            
            echo "=== Permission Summary ==="
            echo "Total items: $(find "$target_path" | wc -l)"
            echo "Directories: $(find "$target_path" -type d | wc -l)"
            echo "Files: $(find "$target_path" -type f | wc -l)"
            echo ""
            
            echo "=== World-Writable Files (Security Risk) ==="
            find "$target_path" -type f -perm -002 -ls 2>/dev/null || echo "None found"
            echo ""
            
            echo "=== SUID/SGID Files ==="
            find "$target_path" -type f \( -perm -4000 -o -perm -2000 \) -ls 2>/dev/null || echo "None found"
            echo ""
            
            echo "=== Files with No Owner/Group ==="
            find "$target_path" -nouser -o -nogroup 2>/dev/null || echo "None found"
            
        else
            echo "=== Single File Permissions ==="
            ls -la "$target_path"
        fi
        
    } > "$audit_file"
    
    echo "📊 Audit report saved to: $audit_file"
    log_action "Permission audit completed: $audit_file"
}

# Fix common permission issues
fix_common_issues() {
    echo "🔧 Fixing common permission issues..."
    
    # Fix world-writable files
    echo "Fixing world-writable files..."
    local world_writable
    world_writable=$(find /Users -type f -perm -002 2>/dev/null | head -10)
    
    if [[ -n "$world_writable" ]]; then
        echo "Found world-writable files:"
        echo "$world_writable"
        
        echo "$world_writable" | while read -r file; do
            if [[ -f "$file" ]]; then
                echo "Fixing: $file"
                sudo chmod o-w "$file"
                log_action "Removed world-write permission from: $file"
            fi
        done
    else
        echo "✅ No world-writable files found"
    fi
    
    # Fix common application permission issues
    echo "Fixing application permissions..."
    if [[ -d "/Applications" ]]; then
        sudo find /Applications -name "*.app" -type d -exec chmod 755 {} \; 2>/dev/null
        log_action "Fixed application permissions in /Applications"
    fi
    
    # Fix user home directory permissions
    echo "Fixing user home directory permissions..."
    for user_home in /Users/*; do
        if [[ -d "$user_home" && "$(basename "$user_home")" != "Shared" ]]; then
            username=$(basename "$user_home")
            if id "$username" &>/dev/null; then
                sudo chmod 755 "$user_home"
                sudo chown "$username:staff" "$user_home"
                log_action "Fixed home directory permissions for: $username"
            fi
        fi
    done
    
    echo "✅ Common permission issues fixed"
}

# Generate permission report
generate_permission_report() {
    local report_file="$REPORT_DIR/permission_report_$(date +%Y%m%d_%H%M%S).txt"
    
    echo "📊 Generating comprehensive permission report..."
    
    {
        echo "MacFleet Permission Management Report"
        echo "Generated: $(date)"
        echo "Hostname: $(hostname)"
        echo "User: $(whoami)"
        echo "======================================="
        echo ""
        
        echo "=== System Information ==="
        echo "macOS Version: $(sw_vers -productVersion)"
        echo "Build: $(sw_vers -buildVersion)"
        echo "Kernel: $(uname -r)"
        echo ""
        
        echo "=== Critical Directory Permissions ==="
        for dir in "/Applications" "/System" "/usr" "/etc" "/var"; do
            if [[ -d "$dir" ]]; then
                echo "$dir: $(ls -ld "$dir" | awk '{print $1, $3, $4}')"
            fi
        done
        echo ""
        
        echo "=== User Home Directory Permissions ==="
        for user_home in /Users/*; do
            if [[ -d "$user_home" ]]; then
                echo "$(basename "$user_home"): $(ls -ld "$user_home" | awk '{print $1, $3, $4}')"
            fi
        done
        echo ""
        
        echo "=== Security Concerns ==="
        echo "World-writable files: $(find /Users -type f -perm -002 2>/dev/null | wc -l)"
        echo "SUID files: $(find /usr -type f -perm -4000 2>/dev/null | wc -l)"
        echo "SGID files: $(find /usr -type f -perm -2000 2>/dev/null | wc -l)"
        echo ""
        
        echo "=== Recent Permission Changes ==="
        tail -20 "$LOG_FILE" 2>/dev/null || echo "No recent changes logged"
        
    } > "$report_file"
    
    echo "📊 Report saved to: $report_file"
    log_action "Permission report generated: $report_file"
}

# Main execution function
main() {
    local action="${1:-help}"
    local target="${2:-}"
    local permission="${3:-}"
    
    log_action "=== MacFleet Permission Management Started ==="
    
    setup_directories
    
    case "$action" in
        "view")
            if [[ -n "$target" ]]; then
                audit_permissions "$target"
            else
                echo "❌ Please specify target path"
                echo "Usage: $0 view /path/to/target"
            fi
            ;;
        "set")
            if [[ -n "$target" && -n "$permission" ]]; then
                create_permission_backup "$target"
                chmod "$permission" "$target"
                log_action "Set permissions $permission on $target"
            else
                echo "❌ Please specify target and permission"
                echo "Usage: $0 set /path/to/target 755"
            fi
            ;;
        "policy")
            if [[ -n "$target" ]]; then
                apply_enterprise_policy "$target"
            else
                echo "❌ Please specify policy name"
                echo "Available policies: secure_documents, shared_workspace, application_deployment, system_hardening"
            fi
            ;;
        "audit")
            if [[ -n "$target" ]]; then
                audit_permissions "$target"
            else
                audit_permissions "/Users"
            fi
            ;;
        "fix")
            fix_common_issues
            ;;
        "report")
            generate_permission_report
            ;;
        "help"|*)
            echo "MacFleet Permission Management Tool"
            echo "Usage: $0 [action] [target] [permission]"
            echo ""
            echo "Actions:"
            echo "  view [path]       - View permissions for path"
            echo "  set [path] [perm] - Set permissions (e.g., 755)"
            echo "  policy [name]     - Apply enterprise permission policy"
            echo "  audit [path]      - Audit permissions and security"
            echo "  fix               - Fix common permission issues"
            echo "  report            - Generate comprehensive report"
            echo "  help              - Show this help message"
            echo ""
            echo "Policies:"
            echo "  secure_documents     - Apply secure document permissions"
            echo "  shared_workspace     - Configure shared workspace permissions"
            echo "  application_deployment - Set application directory permissions"
            echo "  system_hardening     - Apply system security hardening"
            ;;
    esac
    
    log_action "=== MacFleet Permission Management Completed ==="
}

# Execute main function
main "$@"

Common Permission Scenarios

Secure File Storage

# Create secure directory with restricted access
sudo mkdir -p /opt/macfleet/secure
sudo chmod 700 /opt/macfleet/secure
sudo chown root:admin /opt/macfleet/secure

Shared Team Directory

# Create shared directory for team collaboration
sudo mkdir -p /Users/Shared/TeamProject
sudo chmod 775 /Users/Shared/TeamProject
sudo chgrp staff /Users/Shared/TeamProject

Application Deployment

# Set standard application permissions
sudo chmod 755 /Applications/MyApp.app
sudo chown root:admin /Applications/MyApp.app

Permission Reference Guide

Common Permission Patterns

Quick Commands Reference

# View permissions
ls -la filename
stat -f "%A %N" filename

# Set permissions
chmod 755 filename              # Octal notation
chmod u=rwx,g=rx,o=rx filename  # Symbolic notation

# Change ownership
chown user:group filename       # Change both user and group
chown user filename            # Change user only
chgrp group filename           # Change group only

# Recursive operations
chmod -R 755 directory/        # Apply to all contents
chown -R user:group directory/ # Change ownership recursively

Security Considerations

• Principle of Least Privilege - Grant minimum necessary permissions
• Regular Audits - Monitor permission changes and compliance
• Backup Before Changes - Always create backups before modifications
• World-Writable Files - Avoid or carefully control world-writable permissions
• SUID/SGID Files - Monitor and limit special permission files
• System Directory Protection - Maintain strict permissions on system directories

Troubleshooting

Permission Denied Errors

# Check current permissions
ls -la /path/to/file

# Check if you have sudo access
sudo -l

# Fix common permission issues
sudo chmod +r /path/to/file    # Add read permission
sudo chmod +x /path/to/file    # Add execute permission

Ownership Issues

# Check current ownership
ls -la /path/to/file

# Fix ownership
sudo chown $(whoami) /path/to/file    # Make current user owner
sudo chgrp staff /path/to/file        # Set to staff group

Important Notes

• Administrative privileges may be required for system files
• Backup permissions before making changes for easy restoration
• Test changes on individual devices before fleet deployment
• Document permission policies for compliance and auditing
• Monitor security with regular permission audits