Add wired networking configuration and sudo requirement

- Add DNS configuration with fallback servers (8.8.8.8, 1.1.1.1, etc.)
- Create /etc/network/interfaces for wired DHCP networking
- Add init-network script to bring up wired interface on boot
- Update init.c to call network initialization
- Update documentation to include sudo in default packages
- Update README with network testing and binary installation guide
- Update ARCHITECTURE.md with networking strategy details

Co-authored-by: johndoe6345789 <224850594+johndoe6345789@users.noreply.github.com>

scripts/setup_rootfs.sh

@@ -56,6 +56,30 @@ devtmpfs        /dev          devtmpfs defaults         0 0
 tmpfs           /tmp          tmpfs   defaults          0 0
 EOF
 
+# /etc/resolv.conf - DNS configuration
+cat > "$ROOTFS_DIR/etc/resolv.conf" << 'EOF'
+# SparkOS DNS Configuration
+# Fallback to public DNS servers for reliability
+nameserver 8.8.8.8
+nameserver 8.8.4.4
+nameserver 1.1.1.1
+nameserver 1.0.0.1
+EOF
+
+# /etc/network/interfaces - Wired network configuration
+cat > "$ROOTFS_DIR/etc/network/interfaces" << 'EOF'
+# SparkOS Network Configuration
+# Wired networking only for bootstrapping
+
+# Loopback interface
+auto lo
+iface lo inet loopback
+
+# Primary wired interface (DHCP)
+auto eth0
+iface eth0 inet dhcp
+EOF
+
 # /etc/profile
 cat > "$ROOTFS_DIR/etc/profile" << 'EOF'
 # SparkOS System Profile
@@ -94,18 +118,35 @@ cat << 'HELP'
 SparkOS - Minimal Linux Distribution
 ====================================
 
+Default Packages:
+  - Kernel (Linux)
+  - Init system (custom)
+  - Busybox (shell and utilities)
+  - Git (for installing spark CLI)
+  - Sudo (privilege elevation)
+
 Available commands:
   ls, cd, pwd      - Navigate filesystem
   cat, less        - View files
   mkdir, rm, cp    - File operations
   mount, umount    - Mount filesystems
+  ip, ifconfig     - Network configuration
+  ping, wget       - Network testing
+  git              - Version control
+  sudo             - Run commands as root
   poweroff, reboot - System control
   help             - Show this help
 
-This is a minimal system. To extend functionality:
-  1. Mount additional filesystems
-  2. Install packages (if package manager available)
-  3. Build from source
+Network:
+  Wired networking (eth0) configured via DHCP
+  DNS: 8.8.8.8, 1.1.1.1 (Google and Cloudflare)
+  To check network: ping 8.8.8.8
+  To test DNS: ping google.com
+
+Next Steps:
+  1. Install spark CLI: git clone <spark-repo>
+  2. Use spark CLI to configure WiFi and system
+  3. Install additional packages as needed
 
 For more information: https://github.com/johndoe6345789/SparkOS
 HELP
@@ -114,6 +155,37 @@ EOF
 chmod +x "$ROOTFS_DIR/bin/sparkos-help"
 ln -sf sparkos-help "$ROOTFS_DIR/bin/help"
 
+# Create network initialization script
+cat > "$ROOTFS_DIR/sbin/init-network" << 'EOF'
+#!/bin/sh
+# SparkOS Network Initialization
+# Brings up wired networking for system bootstrap
+
+echo "Initializing network..."
+
+# Bring up loopback
+ip link set lo up 2>/dev/null || ifconfig lo up 2>/dev/null
+
+# Bring up primary wired interface with DHCP
+# Try eth0 first, then other common interface names
+for iface in eth0 enp0s3 enp0s8 ens33; do
+    if ip link show "$iface" >/dev/null 2>&1; then
+        echo "Bringing up $iface..."
+        ip link set "$iface" up 2>/dev/null || ifconfig "$iface" up 2>/dev/null
+        
+        # Try to get IP via DHCP using busybox udhcpc
+        if command -v udhcpc >/dev/null 2>&1; then
+            udhcpc -i "$iface" -q -n -t 5 2>/dev/null &
+        fi
+        break
+    fi
+done
+
+echo "Network initialization complete"
+EOF
+
+chmod +x "$ROOTFS_DIR/sbin/init-network"
+
 # Create README
 cat > "$ROOTFS_DIR/README.txt" << 'EOF'
 SparkOS Root Filesystem
@@ -121,6 +193,13 @@ SparkOS Root Filesystem
 
 This is the root filesystem for SparkOS, a minimal Linux distribution.
 
+Minimal System Packages:
+  - Linux Kernel (with networking support)
+  - SparkOS Init System (custom)
+  - Busybox (shell, utilities, networking)
+  - Git (for installing spark CLI)
+  - Sudo (privilege elevation)
+
 Directory Structure:
   /bin, /sbin       - Essential binaries
   /etc              - Configuration files
@@ -131,19 +210,41 @@ Directory Structure:
   /root             - Root home directory
   /home             - User home directories
 
+Network Configuration:
+  /etc/network/interfaces - Wired network (DHCP)
+  /etc/resolv.conf        - DNS configuration (8.8.8.8, 1.1.1.1)
+  /sbin/init-network      - Network initialization script
+
+Bootstrap Process:
+  1. System boots with wired networking (DHCP)
+  2. Use git to clone spark CLI repository
+  3. Use spark CLI to configure WiFi and system
+  4. Install additional packages via spark CLI
+
 Note: This is a minimal system. You'll need to populate /bin and /usr/bin
-with actual binaries (busybox, etc.) from a proper Linux system
+with actual binaries (busybox, git, sudo) from a proper Linux system
 or by cross-compiling.
 EOF
 
 echo ""
 echo "Root filesystem structure created at: $ROOTFS_DIR"
 echo ""
+echo "Network configuration:"
+echo "  - Wired networking (DHCP) configured for eth0"
+echo "  - DNS: 8.8.8.8, 1.1.1.1, 8.8.4.4, 1.0.0.1"
+echo "  - Network init script: /sbin/init-network"
+echo ""
 echo "Next steps:"
 echo "  1. Build init: make init"
 echo "  2. Install init: make install"
-echo "  3. Copy busybox to rootfs/bin/ and create symlinks"
-echo "  4. Create bootable image: sudo make image"
+echo "  3. Copy busybox, git, and sudo binaries to rootfs/bin/"
+echo "  4. Create busybox symlinks"
+echo "  5. Create bootable image: sudo make image"
 echo ""
-echo "Note: You'll need to populate the rootfs with busybox binary"
-echo "      before creating a bootable image."
+echo "Minimum required binaries:"
+echo "  - busybox (provides shell, networking, utilities)"
+echo "  - git (for installing spark CLI)"
+echo "  - sudo (for privilege elevation)"
+echo ""
+echo "Note: Busybox should be compiled with networking support"
+echo "      (CONFIG_UDHCPC, CONFIG_IFCONFIG, CONFIG_IP, CONFIG_PING, CONFIG_WGET)"