Synapse-Ubuntu-ZFS/etc/matrix-synapse/conf.d/password_config.yaml

password_config:
   # Uncomment to disable password login
   #
   #enabled: false

   # Uncomment to disable authentication against the local password
   # database. This is ignored if `enabled` is false, and is only useful
   # if you have other password_providers.
   #
   #localdb_enabled: false

   # Uncomment and change to a secret random string for extra security.
   # DO NOT CHANGE THIS AFTER INITIAL SETUP!
   #
   pepper: "REDACTED"

   # Define and enforce a password policy. Each parameter is optional.
   # This is an implementation of MSC2000.
   #
   policy:
      # Whether to enforce the password policy.
      # Defaults to 'false'.
      #
      enabled: true

      # Minimum accepted length for a password.
      # Defaults to 0.
      #
      minimum_length: 16

      # Whether a password must contain at least one digit.
      # Defaults to 'false'.
      #
      require_digit: true

      # Whether a password must contain at least one symbol.
      # A symbol is any character that's not a number or a letter.
      # Defaults to 'false'.
      #
      require_symbol: true

      # Whether a password must contain at least one lowercase letter.
      # Defaults to 'false'.
      #
      require_lowercase: true

      # Whether a password must contain at least one uppercase letter.
      # Defaults to 'false'.
      #
      require_uppercase: true