common regexp

 https://owasp.org/www-community/OWASP_Validation_Regex_Repository

common regexp use-cases

Generating a cookie secret

Generating a cookie secret 

required step for a lot of web-based use-case when a cookie must be stored on the client side, for example with oauth2-proxy to set-up remote authentication.

• docker / python 

docker run -ti --rm python:3-alpine python -c 'import secrets,base64; print(base64.b64encode(base64.b64encode(secrets.token_bytes(16))));'

Followings solutions are from : https://oauth2-proxy.github.io/oauth2-proxy/docs/configuration/overview (v7.2.x)

• Python

python -c 'import os,base64; print(base64.urlsafe_b64encode(os.urandom(32)).decode())'

• Bash

dd if=/dev/urandom bs=32 count=1 2>/dev/null | base64 | tr -d -- '\n' | tr -- '+/' '-_'; echo

• Open SSL

openssl rand -base64 32 | tr -- '+/' '-_'

• PowerShell

# Add System.Web assembly to session, just in case
Add-Type -AssemblyName System.Web
[Convert]::ToBase64String([System.Text.Encoding]::UTF8.GetBytes([System.Web.Security.Membership]::GeneratePassword(32,4))).Replace("+","-").Replace("/","_")

• Terraform

# Valid 32 Byte Base64 URL encoding set that will decode to 24 []byte AES-192 secret
resource "random_password" "cookie_secret" {
  length           = 32
  override_special = "-_"
}

Caddy + xcaddy within a docker container

Start Caddy within a docker container and add a plugin.

https://caddyserver.com/docs/modules/security

./docker-compose.yml

version: '3.4'
networks:
  monitor-net:
    driver: bridge
volumes:
    caddy_data: {}
services:
  caddy:
    # cf. https://github.com/caddyserver/caddy/releases
    # image: caddy:2.5.0
    build:
      context: ./caddy/ # where to look for the Dockerfile
      dockerfile: Dockerfile # actual name of the Dockerfile
      args:
        image_ref: caddy:2.5.0
    container_name: caddy
    ports:
      - "80:80"
      - "443:443"
    volumes:
      - ./caddy:/etc/caddy
      - caddy_data:/data
    env_file:
      ./.env
    restart: unless-stopped
    networks:
      - monitor-net
    labels:
      org.label-schema.group: "monitoring"

image_ref: caddy:2.5.0 # image reference used twice in the Dockerfile, once with ${image_ref}-builder, once directly

./caddy/Dockerfile :

ARG image_ref
FROM ${image_ref}-builder AS caddy-build
RUN xcaddy build --with github.com/greenpau/caddy-security
FROM ${image_ref}
COPY --from=caddy-build /usr/bin/caddy /usr/bin/caddy

Caddyfile must exist (content not relevant here):

./caddy/Caddyfile

command :

docker-compose  up --build caddy