From b50046d4978cad15d7ca4ff04b5134f81754bfee Mon Sep 17 00:00:00 2001
From: "tiago.ferreira" <tiago.ferreira@fatecourinhos.edu.br>
Date: Tue, 15 Sep 2026 20:04:20 +0000
Subject: [PATCH] Adicionar conf-rede

---
 conf-rede | 821 ++++++++++++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 821 insertions(+)
 create mode 100644 conf-rede

diff --git a/conf-rede b/conf-rede
new file mode 100644
index 0000000..942eba6
--- /dev/null
+++ b/conf-rede
@@ -0,0 +1,821 @@
+#!/bin/bash
+
+set -e
+
+# ============================================================
+# CONFIGURAÇÃO DE REDE / GATEWAY - DEBIAN 13
+#
+# - Detecta interfaces de rede
+# - Recria /etc/network/interfaces
+# - DHCP / Estático / Não configurar por interface
+# - Pergunta se a máquina será gateway
+# - Permite selecionar a interface de saída (WAN)
+# - Ativa IPv4 forwarding permanentemente
+# - Configura nftables
+# - Configura masquerade (NAT) permanentemente
+#
+# Compatível com:
+#
+# curl -fsSL URL | bash
+#
+# ============================================================
+
+
+# ============================================================
+# FUNÇÕES
+# ============================================================
+
+read_tty() {
+    local prompt="$1"
+    local varname="$2"
+
+    read -rp "$prompt" "$varname" < /dev/tty
+}
+
+
+valid_ipv4() {
+    local ip="$1"
+    local IFS=.
+    local -a octets
+
+    read -ra octets <<< "$ip"
+
+    [ "${#octets[@]}" -eq 4 ] || return 1
+
+    for octet in "${octets[@]}"; do
+
+        [[ "$octet" =~ ^[0-9]+$ ]] || return 1
+
+        [ "$octet" -ge 0 ] 2>/dev/null || return 1
+        [ "$octet" -le 255 ] 2>/dev/null || return 1
+
+    done
+
+    return 0
+}
+
+
+yes_answer() {
+
+    case "$1" in
+        s|S|sim|SIM|Sim|y|Y|yes|YES|Yes)
+            return 0
+            ;;
+        *)
+            return 1
+            ;;
+    esac
+}
+
+
+# ============================================================
+# ROOT
+# ============================================================
+
+if [ "$EUID" -ne 0 ]; then
+
+    echo
+    echo "ERRO: execute este script como root."
+    echo
+
+    exit 1
+
+fi
+
+
+# ============================================================
+# CABEÇALHO
+# ============================================================
+
+clear 2>/dev/null || true
+
+echo
+echo "============================================================"
+echo " CONFIGURAÇÃO DE REDE - DEBIAN 13"
+echo "============================================================"
+echo
+
+
+# ============================================================
+# VERIFICA NFTABLES
+# ============================================================
+
+if ! command -v nft >/dev/null 2>&1; then
+
+    echo "ERRO: nftables não está instalado."
+    echo
+    echo "Instale antes com:"
+    echo
+    echo "  apt update"
+    echo "  apt install nftables"
+    echo
+
+    exit 1
+
+fi
+
+
+# ============================================================
+# DETECTA INTERFACES
+# ============================================================
+
+mapfile -t INTERFACES < <(
+    find /sys/class/net \
+        -mindepth 1 \
+        -maxdepth 1 \
+        -printf '%f\n' |
+        grep -v '^lo$' |
+        grep -Ev '^(docker|br-|veth|virbr|tun|tap)' |
+        sort
+)
+
+
+if [ "${#INTERFACES[@]}" -eq 0 ]; then
+
+    echo "ERRO: nenhuma interface de rede encontrada."
+
+    exit 1
+
+fi
+
+
+echo "Interfaces encontradas:"
+echo
+
+
+for IFACE in "${INTERFACES[@]}"; do
+
+    MAC="desconhecido"
+    STATE="desconhecido"
+
+    if [ -f "/sys/class/net/$IFACE/address" ]; then
+        MAC=$(cat "/sys/class/net/$IFACE/address")
+    fi
+
+    if [ -f "/sys/class/net/$IFACE/operstate" ]; then
+        STATE=$(cat "/sys/class/net/$IFACE/operstate")
+    fi
+
+    echo "Interface : $IFACE"
+    echo "MAC       : $MAC"
+    echo "Estado    : $STATE"
+    echo
+
+done
+
+
+# ============================================================
+# CONFIRMAÇÃO
+# ============================================================
+
+echo "ATENÇÃO:"
+echo
+echo "O arquivo /etc/network/interfaces será recriado."
+echo
+
+read_tty "Deseja continuar? [S/n]: " CONFIRM
+
+
+case "$CONFIRM" in
+
+    n|N|nao|não|NAO|NÃO)
+
+        echo
+        echo "Operação cancelada."
+        exit 0
+        ;;
+
+esac
+
+
+# ============================================================
+# BACKUP
+# ============================================================
+
+BACKUP_DIR="/root/network-backup-$(date +%Y%m%d-%H%M%S)"
+
+mkdir -p "$BACKUP_DIR"
+
+
+if [ -f /etc/network/interfaces ]; then
+
+    cp -a /etc/network/interfaces \
+        "$BACKUP_DIR/interfaces"
+
+fi
+
+
+if [ -f /etc/nftables.conf ]; then
+
+    cp -a /etc/nftables.conf \
+        "$BACKUP_DIR/nftables.conf"
+
+fi
+
+
+echo
+echo "Backup:"
+echo "$BACKUP_DIR"
+echo
+
+
+# ============================================================
+# CRIA /etc/network/interfaces
+# ============================================================
+
+cat > /etc/network/interfaces <<'EOF'
+# ============================================================
+# Configuração de rede
+# Gerada automaticamente
+# ============================================================
+
+auto lo
+iface lo inet loopback
+
+EOF
+
+
+# ============================================================
+# INTERFACES CONFIGURADAS
+# ============================================================
+
+CONFIGURED_INTERFACES=()
+
+
+# ============================================================
+# CONFIGURA CADA INTERFACE
+# ============================================================
+
+for IFACE in "${INTERFACES[@]}"; do
+
+    MAC="desconhecido"
+
+    if [ -f "/sys/class/net/$IFACE/address" ]; then
+        MAC=$(cat "/sys/class/net/$IFACE/address")
+    fi
+
+
+    echo
+    echo "============================================================"
+    echo " INTERFACE: $IFACE"
+    echo " MAC:       $MAC"
+    echo "============================================================"
+    echo
+    echo "1) DHCP"
+    echo "2) IP estático"
+    echo "3) Não configurar"
+    echo
+
+
+    while true; do
+
+        read_tty "Escolha [1/2/3]: " OPTION
+
+
+        case "$OPTION" in
+
+            # ====================================================
+            # DHCP
+            # ====================================================
+
+            1)
+
+                cat >> /etc/network/interfaces <<EOF
+
+# ------------------------------------------------------------
+# Interface $IFACE - DHCP
+# ------------------------------------------------------------
+
+auto $IFACE
+allow-hotplug $IFACE
+iface $IFACE inet dhcp
+
+EOF
+
+                CONFIGURED_INTERFACES+=("$IFACE")
+
+                echo
+                echo "$IFACE configurada como DHCP."
+
+                break
+                ;;
+
+
+            # ====================================================
+            # ESTÁTICO
+            # ====================================================
+
+            2)
+
+                echo
+                echo "Configuração estática de $IFACE"
+                echo
+
+
+                # ------------------------------------------------
+                # IP
+                # ------------------------------------------------
+
+                while true; do
+
+                    read_tty "Endereço IPv4: " IPADDR
+
+                    if valid_ipv4 "$IPADDR"; then
+                        break
+                    fi
+
+                    echo "Endereço IPv4 inválido."
+
+                done
+
+
+                # ------------------------------------------------
+                # PREFIXO
+                # ------------------------------------------------
+
+                while true; do
+
+                    read_tty "Prefixo [ex.: 24]: " PREFIX
+
+                    if [[ "$PREFIX" =~ ^[0-9]+$ ]] &&
+                       [ "$PREFIX" -ge 0 ] &&
+                       [ "$PREFIX" -le 32 ]; then
+
+                        break
+
+                    fi
+
+                    echo "Prefixo inválido."
+
+                done
+
+
+                # ------------------------------------------------
+                # GATEWAY
+                # ------------------------------------------------
+
+                while true; do
+
+                    read_tty "Gateway [ENTER para nenhum]: " GATEWAY
+
+                    if [ -z "$GATEWAY" ]; then
+                        break
+                    fi
+
+                    if valid_ipv4 "$GATEWAY"; then
+                        break
+                    fi
+
+                    echo "Gateway inválido."
+
+                done
+
+
+                # ------------------------------------------------
+                # DNS
+                # ------------------------------------------------
+
+                while true; do
+
+                    read_tty "DNS [ex.: 172.16.0.2 8.8.8.8] [ENTER para nenhum]: " DNS
+
+                    if [ -z "$DNS" ]; then
+                        break
+                    fi
+
+                    DNS_VALID=1
+
+                    for DNS_IP in $DNS; do
+
+                        if ! valid_ipv4 "$DNS_IP"; then
+                            DNS_VALID=0
+                            break
+                        fi
+
+                    done
+
+
+                    if [ "$DNS_VALID" -eq 1 ]; then
+                        break
+                    fi
+
+                    echo "DNS inválido."
+
+                done
+
+
+                # ------------------------------------------------
+                # DNS SEARCH
+                # ------------------------------------------------
+
+                read_tty "Domínio de pesquisa DNS [ENTER para nenhum]: " DNS_SEARCH
+
+
+                # ------------------------------------------------
+                # GRAVA
+                # ------------------------------------------------
+
+                cat >> /etc/network/interfaces <<EOF
+
+# ------------------------------------------------------------
+# Interface $IFACE - ESTÁTICA
+# ------------------------------------------------------------
+
+auto $IFACE
+allow-hotplug $IFACE
+iface $IFACE inet static
+    address $IPADDR/$PREFIX
+EOF
+
+
+                if [ -n "$GATEWAY" ]; then
+
+                    echo "    gateway $GATEWAY" \
+                        >> /etc/network/interfaces
+
+                fi
+
+
+                if [ -n "$DNS" ]; then
+
+                    echo "    dns-nameservers $DNS" \
+                        >> /etc/network/interfaces
+
+                fi
+
+
+                if [ -n "$DNS_SEARCH" ]; then
+
+                    echo "    dns-search $DNS_SEARCH" \
+                        >> /etc/network/interfaces
+
+                fi
+
+
+                CONFIGURED_INTERFACES+=("$IFACE")
+
+
+                echo
+                echo "$IFACE configurada com IP estático."
+
+                break
+                ;;
+
+
+            # ====================================================
+            # NÃO CONFIGURAR
+            # ====================================================
+
+            3)
+
+                echo
+                echo "$IFACE não será configurada."
+
+                break
+                ;;
+
+
+            *)
+
+                echo
+                echo "Opção inválida."
+                ;;
+
+        esac
+
+    done
+
+done
+
+
+chmod 644 /etc/network/interfaces
+
+
+# ============================================================
+# GATEWAY
+# ============================================================
+
+echo
+echo "============================================================"
+echo " CONFIGURAÇÃO DE GATEWAY"
+echo "============================================================"
+echo
+
+read_tty "Esta máquina será gateway para outras redes? [s/N]: " IS_GATEWAY
+
+
+if yes_answer "$IS_GATEWAY"; then
+
+
+    # ========================================================
+    # VERIFICA INTERFACES CONFIGURADAS
+    # ========================================================
+
+    if [ "${#CONFIGURED_INTERFACES[@]}" -lt 2 ]; then
+
+        echo
+        echo "ATENÇÃO:"
+        echo
+        echo "Um gateway normalmente precisa de pelo menos"
+        echo "duas interfaces configuradas."
+        echo
+
+    fi
+
+
+    # ========================================================
+    # SELEÇÃO DA WAN
+    # ========================================================
+
+    echo
+    echo "Selecione a interface que possui saída para a Internet:"
+    echo
+
+
+    INDEX=1
+
+    for IFACE in "${CONFIGURED_INTERFACES[@]}"; do
+
+        echo "$INDEX) $IFACE"
+
+        INDEX=$((INDEX + 1))
+
+    done
+
+
+    echo
+
+
+    while true; do
+
+        read_tty "Interface de saída: " WAN_OPTION
+
+
+        if [[ "$WAN_OPTION" =~ ^[0-9]+$ ]] &&
+           [ "$WAN_OPTION" -ge 1 ] &&
+           [ "$WAN_OPTION" -le "${#CONFIGURED_INTERFACES[@]}" ]; then
+
+            WAN_INTERFACE="${CONFIGURED_INTERFACES[$((WAN_OPTION - 1))]}"
+
+            break
+
+        fi
+
+
+        echo "Opção inválida."
+
+    done
+
+
+    echo
+    echo "Interface WAN selecionada: $WAN_INTERFACE"
+    echo
+
+
+    # ========================================================
+    # FORWARD IPV4 PERMANENTE
+    # ========================================================
+
+    echo "Ativando IPv4 forwarding..."
+
+
+    cat > /etc/sysctl.d/99-ip-forward.conf <<'EOF'
+# ============================================================
+# IPv4 Forwarding
+# ============================================================
+
+net.ipv4.ip_forward = 1
+EOF
+
+
+    sysctl -w net.ipv4.ip_forward=1 >/dev/null
+
+
+    # ========================================================
+    # NFTABLES
+    # ========================================================
+
+    echo "Configurando nftables..."
+
+
+    cat > /etc/nftables.conf <<EOF
+#!/usr/sbin/nft -f
+
+# ============================================================
+# Firewall / Gateway
+# Debian 13
+#
+# Arquivo gerado automaticamente
+# ============================================================
+
+flush ruleset
+
+
+# ============================================================
+# FILTRO
+# ============================================================
+
+table inet filter {
+
+    chain input {
+
+        type filter hook input priority filter;
+        policy accept;
+
+    }
+
+
+    chain forward {
+
+        type filter hook forward priority filter;
+        policy drop;
+
+        # Permite conexões já estabelecidas
+        ct state established,related accept
+
+        # Permite tráfego entrando pelas interfaces internas
+        # e saindo pela WAN
+EOF
+
+
+    # ========================================================
+    # ADICIONA INTERFACES LAN
+    # ========================================================
+
+    for IFACE in "${CONFIGURED_INTERFACES[@]}"; do
+
+        if [ "$IFACE" != "$WAN_INTERFACE" ]; then
+
+            echo "        iifname \"$IFACE\" oifname \"$WAN_INTERFACE\" accept" \
+                >> /etc/nftables.conf
+
+        fi
+
+    done
+
+
+    cat >> /etc/nftables.conf <<EOF
+
+    }
+
+}
+
+
+# ============================================================
+# NAT IPv4
+# ============================================================
+
+table ip nat {
+
+    chain postrouting {
+
+        type nat hook postrouting priority srcnat;
+        policy accept;
+
+        oifname "$WAN_INTERFACE" masquerade
+
+    }
+
+}
+EOF
+
+
+    # ========================================================
+    # TESTA NFTABLES
+    # ========================================================
+
+    echo
+    echo "Validando regras do nftables..."
+
+    if ! nft -c -f /etc/nftables.conf; then
+
+        echo
+        echo "ERRO:"
+        echo "A configuração do nftables possui algum problema."
+        echo
+        echo "O backup está em:"
+        echo "$BACKUP_DIR"
+        echo
+
+        exit 1
+
+    fi
+
+
+    # ========================================================
+    # ATIVA NFTABLES
+    # ========================================================
+
+    echo
+    echo "Ativando nftables..."
+
+
+    systemctl enable nftables >/dev/null 2>&1 || true
+
+
+    nft -f /etc/nftables.conf
+
+
+    systemctl restart nftables
+
+
+    # ========================================================
+    # RESULTADO GATEWAY
+    # ========================================================
+
+    echo
+    echo "============================================================"
+    echo " GATEWAY CONFIGURADO"
+    echo "============================================================"
+    echo
+    echo "WAN:"
+    echo "  $WAN_INTERFACE"
+    echo
+    echo "IPv4 Forwarding:"
+    echo "  ATIVADO"
+    echo
+    echo "NAT / Masquerade:"
+    echo "  ATIVADO"
+    echo
+
+
+else
+
+
+    # ========================================================
+    # NÃO É GATEWAY
+    # ========================================================
+
+    echo
+    echo "A máquina não será configurada como gateway."
+    echo
+
+fi
+
+
+# ============================================================
+# RESULTADO FINAL
+# ============================================================
+
+echo
+echo "============================================================"
+echo " CONFIGURAÇÃO FINAL"
+echo "============================================================"
+echo
+
+echo "/etc/network/interfaces:"
+echo
+echo "------------------------------------------------------------"
+
+cat /etc/network/interfaces
+
+echo "------------------------------------------------------------"
+
+
+if yes_answer "$IS_GATEWAY"; then
+
+    echo
+    echo "IPv4 Forward:"
+    echo
+
+    sysctl net.ipv4.ip_forward
+
+    echo
+    echo "Regras nftables:"
+    echo
+    echo "------------------------------------------------------------"
+
+    nft list ruleset
+
+    echo "------------------------------------------------------------"
+
+fi
+
+
+# ============================================================
+# SINCRONIZA
+# ============================================================
+
+sync
+
+
+# ============================================================
+# FINALIZAÇÃO
+# ============================================================
+
+echo
+echo "============================================================"
+echo " CONFIGURAÇÃO CONCLUÍDA"
+echo "============================================================"
+echo
+echo "Backup da configuração anterior:"
+echo
+echo "  $BACKUP_DIR"
+echo
+echo "Recomenda-se reiniciar a máquina para aplicar"
+echo "completamente a nova configuração de interfaces."
+echo
+echo "Execute:"
+echo
+echo "  reboot"
+echo
\ No newline at end of file