WireGuard VPN self-hosted na VPS

# Instalar WireGuard:
sudo apt update && sudo apt install -y wireguard

# Gerar par de chaves do servidor:
wg genkey | sudo tee /etc/wireguard/server_private.key | \
  wg pubkey | sudo tee /etc/wireguard/server_public.key
sudo chmod 600 /etc/wireguard/server_private.key

SERVER_PRIVATE=$(sudo cat /etc/wireguard/server_private.key)
SERVER_PUBLIC=$(sudo cat /etc/wireguard/server_public.key)

# Criar configuração do servidor:
sudo tee /etc/wireguard/wg0.conf << EOF
[Interface]
Address    = 10.8.0.1/24
ListenPort = 51820
PrivateKey = $SERVER_PRIVATE

# Habilitar roteamento de tráfego (para VPN de saída total)
PostUp   = iptables -A FORWARD -i wg0 -j ACCEPT; \
           iptables -t nat -A POSTROUTING -o eth0 -j MASQUERADE
PostDown = iptables -D FORWARD -i wg0 -j ACCEPT; \
           iptables -t nat -D POSTROUTING -o eth0 -j MASQUERADE
EOF

# Habilitar IP forwarding:
sudo sysctl -w net.ipv4.ip_forward=1
echo "net.ipv4.ip_forward=1" | sudo tee -a /etc/sysctl.conf

# Liberar porta UDP no UFW:
sudo ufw allow 51820/udp

# Iniciar WireGuard:
sudo systemctl enable wg-quick@wg0
sudo systemctl start wg-quick@wg0
sudo wg show

# Na máquina cliente — gerar par de chaves:
wg genkey | tee client_private.key | wg pubkey > client_public.key

CLIENT_PRIVATE=$(cat client_private.key)
CLIENT_PUBLIC=$(cat client_public.key)
SERVER_PUBLIC="CHAVE_PUBLICA_DO_SERVIDOR"

# Criar configuração do cliente:
cat > wg-client.conf << EOF
[Interface]
Address    = 10.8.0.2/32       # IP do cliente na VPN
PrivateKey = $CLIENT_PRIVATE
DNS        = 1.1.1.1           # DNS para usar na VPN

[Peer]
PublicKey  = $SERVER_PUBLIC
Endpoint   = IP_VPS:51820
AllowedIPs = 10.8.0.0/24       # apenas tráfego da rede VPN
# AllowedIPs = 0.0.0.0/0       # rotear TODO o tráfego pela VPS
PersistentKeepalive = 25
EOF

# Adicionar o cliente no servidor:
sudo wg set wg0 peer $CLIENT_PUBLIC \
  allowed-ips 10.8.0.2/32

# Salvar a config para persistir após reboot:
sudo wg-quick save wg0

# No cliente — conectar:
# Linux: sudo wg-quick up ./wg-client.conf
# macOS/Windows: importar wg-client.conf no app WireGuard
# iOS/Android: gerar QR code: qrencode -t ansiutf8 < wg-client.conf

#!/bin/bash
# /opt/scripts/wg-add-client.sh — adicionar novo cliente

CLIENT_NAME="${1:-cliente}"
NEXT_IP="${2:-10.8.0.10}"  # passar IP ou incrementar automaticamente
SERVER_PUBLIC=$(cat /etc/wireguard/server_public.key)
VPS_IP=$(curl -s ifconfig.me)

# Gerar chaves do cliente:
CLIENT_PRIVATE=$(wg genkey)
CLIENT_PUBLIC=$(echo "$CLIENT_PRIVATE" | wg pubkey)

# Criar arquivo de configuração:
cat > "/opt/wireguard/clients/${CLIENT_NAME}.conf" << EOF
[Interface]
Address    = ${NEXT_IP}/32
PrivateKey = $CLIENT_PRIVATE
DNS        = 1.1.1.1

[Peer]
PublicKey  = $SERVER_PUBLIC
Endpoint   = ${VPS_IP}:51820
AllowedIPs = 10.8.0.0/24
PersistentKeepalive = 25
EOF

# Adicionar ao servidor:
sudo wg set wg0 peer "$CLIENT_PUBLIC" allowed-ips "${NEXT_IP}/32"
sudo wg-quick save wg0

echo "Cliente '$CLIENT_NAME' adicionado com IP ${NEXT_IP}"
echo "Config salva em: /opt/wireguard/clients/${CLIENT_NAME}.conf"

# Gerar QR code para mobile:
qrencode -t ansiutf8 < "/opt/wireguard/clients/${CLIENT_NAME}.conf"

# Cenário: VPS-A (São Paulo) ↔ VPS-B (Frankfurt)
# Objetivo: serviços na VPS-A acessam banco na VPS-B via rede privada

# Na VPS-A (servidor/cliente):
# wg0.conf — adicionar peer VPS-B:
[Peer]
PublicKey  = CHAVE_PUBLICA_VPS_B
Endpoint   = IP_VPS_B:51820
AllowedIPs = 10.8.0.2/32, 192.168.2.0/24  # IP da VPN + rede privada da VPS-B

# Na VPS-B (servidor/cliente):
# wg0.conf — adicionar peer VPS-A:
[Peer]
PublicKey  = CHAVE_PUBLICA_VPS_A
Endpoint   = IP_VPS_A:51820
AllowedIPs = 10.8.0.1/32, 192.168.1.0/24  # IP da VPN + rede privada da VPS-A

# Verificar conectividade após setup:
# Na VPS-A:
ping 10.8.0.2              # ping para o endpoint WireGuard da VPS-B
psql -h 10.8.0.2 -U postgres meu_banco  # acessar banco na VPS-B

# Monitorar status da conexão:
sudo wg show wg0
sudo wg show wg0 latest-handshakes

# wg-easy: painel web para WireGuard via Docker
# docker-compose.yml:
services:
  wg-easy:
    image: ghcr.io/wg-easy/wg-easy:latest
    cap_add:
      - NET_ADMIN
      - SYS_MODULE
    sysctls:
      - net.ipv4.conf.all.src_valid_mark=1
      - net.ipv4.ip_forward=1
    ports:
      - "51820:51820/udp"        # WireGuard
      - "127.0.0.1:51821:51821"  # UI web
    environment:
      WG_HOST: IP_OU_DOMINIO_DA_VPS
      PASSWORD_HASH: "${WG_PASSWORD_HASH}"    # bcrypt hash
      WG_DEFAULT_ADDRESS: "10.8.0.x"
      WG_DEFAULT_DNS: "1.1.1.1"
    volumes:
      - wg_data:/etc/wireguard
    restart: always

volumes:
  wg_data:

# Gerar hash da senha:
# docker run ghcr.io/wg-easy/wg-easy wgpw SUASENHA
# Acessar UI em: https://vpn.seudominio.com.br (com Nginx na frente)