Class: Sandbox Private

Inherits:
Object show all
Extended by:
Utils::Output::Mixin
Includes:
OS::Linux::Sandbox, OS::Mac::Sandbox, Utils::Output::Mixin
Defined in:
sandbox.rb,
extend/os/linux/sandbox/backend.rb,
extend/os/linux/sandbox/landlock.rb

Overview

This class is part of a private API. This class may only be used in the Homebrew/brew repository. Third parties should avoid using this class if possible, as it may be removed or changed without warning.

Helper class for running a sub-process inside of a sandboxed environment.

Defined Under Namespace

Classes: Landlock, LinuxBackend

Constant Summary collapse

PRIVILEGED_GROUPS =

This constant is part of a private API. This constant may only be used in the Homebrew/brew repository. Third parties should avoid using this constant if possible, as it may be removed or changed without warning.

Privileged groups that are expected to be able to use a working sandbox.

%w[admin staff root wheel].freeze

Instance Attribute Summary collapse

Class Method Summary collapse

Instance Method Summary collapse

Methods included from Utils::Output::Mixin

issue_reporting_message, odebug, odeprecated, odie, odisabled, ofail, oh1, oh1_title, ohai, ohai_title, onoe, opoo, opoo_outside_github_actions, opoo_without_github_actions_annotation, pretty_deprecated, pretty_disabled, pretty_duration, pretty_install_status, pretty_installed, pretty_uninstalled, pretty_unmarked, pretty_upgradable, pretty_warning

Constructor Details

#initialize ⇒ void

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning. 



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# File 'sandbox.rb', line 283

def initialize
  @profile = T.let(SandboxProfile.new, SandboxProfile)
  @failed = T.let(false, T::Boolean)
  @logfile = T.let(nil, T.nilable(T.any(String, Pathname)))
  @start = T.let(nil, T.nilable(Time))
end

Instance Attribute Details

#profile ⇒ SandboxProfile (readonly)

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

Returns:

  • (SandboxProfile) 


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# File 'sandbox.rb', line 681

def profile
  @profile
end

Class Method Details

.available? ⇒ Boolean

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

Returns:

  • (Boolean) 


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# File 'sandbox.rb', line 79

def self.available?
  false
end

.avoid_nested_sandboxing? ⇒ Boolean

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

Skip Homebrew's own sandbox when it is opted into via $HOMEBREW_AVOID_NESTED_SANDBOXING and already running inside another sandbox. The skip is only supported for an unprivileged user in a custom prefix; error out explaining why rather than silently sandboxing (and hanging) when either is not the case.

Returns:

  • (Boolean) 


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# File 'sandbox.rb', line 98

def self.avoid_nested_sandboxing?
  return false unless Homebrew::EnvConfig.avoid_nested_sandboxing?
  return false unless nested_sandbox?

  if Homebrew.default_prefix?
    odie "Refusing to skip the sandbox: `$HOMEBREW_AVOID_NESTED_SANDBOXING` is set " \
         "inside another sandbox but Homebrew is using its default prefix " \
         "(#{HOMEBREW_PREFIX}); this is only supported in a custom prefix."
  end

  privileged_group = PRIVILEGED_GROUPS.find do |name|
    group = Etc.getgrnam(name)
    group && Process.groups.include?(group.gid)
  rescue ArgumentError
    false
  end
  if privileged_group
    odie "Refusing to skip the sandbox: `$HOMEBREW_AVOID_NESTED_SANDBOXING` is set " \
         "inside another sandbox but you are in the privileged `#{privileged_group}` " \
         "group; this is only supported for an unprivileged user."
  end

  true
end

.ensure_sandbox_available! ⇒ void

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

This method returns an undefined value.



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# File 'sandbox.rb', line 187

def self.ensure_sandbox_available!
  return if available?

  raise failure_reason || "The sandbox is not available."
end

.executable ⇒ Pathname?

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

Returns:



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# File 'sandbox.rb', line 241

def self.executable
  executable_candidate_paths.each do |path|
    begin
      candidate = Pathname.new(File.expand_path(executable_name, path))
    rescue ArgumentError
      next
    end

    next if !candidate.file? || !candidate.executable?
    next unless executable_usable?(candidate)

    return candidate
  end

  nil
end

.executable! ⇒ Pathname

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

Returns:



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# File 'sandbox.rb', line 259

def self.executable!
  executable || raise("#{executable_name} is required to use the sandbox.")
end

.executable_candidate_paths ⇒ ::PATH

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

Returns:



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# File 'sandbox.rb', line 233

def self.executable_candidate_paths
  executable_path = Pathname.new(executable_name)
  return PATH.new(executable_path.dirname) if executable_path.absolute?

  PATH.new(ORIGINAL_PATHS, ENV.fetch("PATH"), HOMEBREW_ORIGINAL_BREW_FILE.dirname)
end

.executable_name ⇒ String

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

Returns:

Raises:

  • (NotImplementedError) 


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# File 'sandbox.rb', line 228

def self.executable_name
  raise NotImplementedError, "Sandbox is not implemented for this OS."
end

.executable_usable?(_candidate) ⇒ Boolean

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

Parameters:

Returns:

  • (Boolean) 


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# File 'sandbox.rb', line 264

def self.executable_usable?(_candidate)
  true
end

.failure_reason ⇒ String?

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

Returns:



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# File 'sandbox.rb', line 199

def self.failure_reason
  return if state == :available

  "The sandbox is not available."
end

.full_write_isolation? ⇒ Boolean

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

Returns:

  • (Boolean) 


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# File 'sandbox.rb', line 84

def self.full_write_isolation? = true

.nested_sandbox? ⇒ Boolean

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

Whether Homebrew is itself running inside another sandbox, which would make its own nested sandbox hang (macOS) or fail to start (Linux). Overridden per-OS.

Returns:

  • (Boolean) 


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# File 'sandbox.rb', line 90

def self.nested_sandbox? = false

.reset_state! ⇒ void

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

This method returns an undefined value.



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# File 'sandbox.rb', line 206

def self.reset_state!; end

.run_command(*command, writable_path:, deny_network: false) ⇒ void

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

This method returns an undefined value.

Parameters:



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# File 'sandbox.rb', line 209

def self.run_command(*command, writable_path:, deny_network: false)
  ensure_sandbox_available!

  writable_path = Pathname(writable_path).expand_path
  if !writable_path.directory? || !writable_path.writable?
    raise UsageError,
          "`#{writable_path}` is not a writable directory."
  end

  writable_path = writable_path.realpath
  sandbox = new
  sandbox.allow_write_temp_and_cache
  sandbox.allow_write_path writable_path
  sandbox.deny_read_home
  sandbox.deny_all_network if deny_network
  sandbox.run "/bin/sh", "-c", "cd \"$1\" && shift && exec \"$@\"", "brew-sandbox-exec", writable_path, *command
end

.run_or_fork(*args, step:, warn_without_sandbox: true, &_block) ⇒ void

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

This method returns an undefined value.

Parameters:



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# File 'sandbox.rb', line 146

def self.run_or_fork(*args, step:, warn_without_sandbox: true, &_block)
  if use_for?(step, warn_without_sandbox:)
    sandbox = new
    yield sandbox
    sandbox.run(*args)
  else
    Utils.safe_fork { exec(*args) }
  end
end

.state ⇒ Symbol

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

Returns:



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# File 'sandbox.rb', line 194

def self.state
  available? ? :available : :unavailable
end

.terminal_ioctl_request ⇒ Integer

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

Returns:

Raises:

  • (NotImplementedError) 


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# File 'sandbox.rb', line 269

def self.terminal_ioctl_request
  raise NotImplementedError, "Sandbox is not implemented for this OS."
end

.tty_state ⇒ String?

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

The terminal state to restore after a PTY passthrough. It cannot change in the background while brew runs (each passthrough restores it), so capture it once per process. nil when it cannot be captured.

Returns:



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# File 'sandbox.rb', line 277

def self.tty_state
  @tty_state ||= T.let(Utils.popen_read("stty", "-g").chomp, T.nilable(String))
  @tty_state.presence
end

.use_for?(step, warn_without_sandbox: true) ⇒ Boolean

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

Parameters:

  • step (String)
  • warn_without_sandbox (Boolean) (defaults to: true)

Returns:

  • (Boolean) 


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# File 'sandbox.rb', line 124

def self.use_for?(step, warn_without_sandbox: true)
  unless available?
    opoo "Sandbox unavailable: #{step} without sandboxing!" if warn_without_sandbox
    return false
  end

  if avoid_nested_sandboxing?
    opoo "#{step.capitalize} without Homebrew's sandbox; relying on the outer sandbox." if warn_without_sandbox
    return false
  end

  true
end

.with_preserved_brew_file(&block) ⇒ void

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

This method returns an undefined value.

Landlock cannot protect bin/brew while allowing writes to bin, so a sandboxed install hook could replace brew to persist into later commands.

Parameters:

  • block (T.proc.void) 


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# File 'sandbox.rb', line 159

def self.with_preserved_brew_file(&block)
  return yield if full_write_isolation?

  brew_file = HOMEBREW_PREFIX/"bin/brew"
  File.open(brew_file.dirname) do |brew_directory|
    brew_directory_mode = brew_directory.stat.mode & 07777
    symlink = brew_file.symlink?
    contents = symlink ? brew_file.readlink.to_s : brew_file.binread
    brew_file_mode = brew_file.lstat.mode & 07777

    begin
      yield
    ensure
      brew_directory.chmod brew_directory_mode
      if symlink && (!brew_file.symlink? || brew_file.readlink.to_s != contents)
        FileUtils.rm_rf brew_file
        brew_file.make_symlink contents
      elsif !symlink && (brew_file.symlink? || !brew_file.file? || brew_file.binread != contents ||
                         (brew_file.lstat.mode & 07777) != brew_file_mode)
        FileUtils.rm_rf brew_file
        brew_file.atomic_write contents
        brew_file.chmod brew_file_mode
      end
    end
  end
end

Instance Method Details

#add_install_hook_rules(network_access_allowed:) ⇒ void

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

This method returns an undefined value.

Parameters:

  • network_access_allowed (Boolean) 


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# File 'sandbox.rb', line 497

def add_install_hook_rules(network_access_allowed:)
  allow_write_temp_and_cache
  deny_write_homebrew_repository
  deny_read_home
  deny_all_network unless network_access_allowed
end

#add_rule(allow:, operation:, filter: nil, modifier: nil) ⇒ void

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

This method returns an undefined value.

Parameters:

  • allow (Boolean)
  • operation (String)
  • filter (SandboxPathFilter, nil) (defaults to: nil)
  • modifier (String, nil) (defaults to: nil) 


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# File 'sandbox.rb', line 299

def add_rule(allow:, operation:, filter: nil, modifier: nil)
  rule = SandboxRule.new(allow:, operation:, filter:, modifier:)
  @profile.add_rule(rule)
end

#allow_cvs ⇒ void

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

This method returns an undefined value.



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# File 'sandbox.rb', line 505

def allow_cvs
  allow_write_path "#{Dir.home(ENV.fetch("USER"))}/.cvspass"
end

#allow_fossil ⇒ void

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

This method returns an undefined value.



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# File 'sandbox.rb', line 510

def allow_fossil
  allow_write_path "#{Dir.home(ENV.fetch("USER"))}/.fossil"
  allow_write_path "#{Dir.home(ENV.fetch("USER"))}/.fossil-journal"
end

#allow_network(path:, type: :literal) ⇒ void

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

This method returns an undefined value.

Parameters:



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# File 'sandbox.rb', line 542

def allow_network(path:, type: :literal)
  add_rule allow: true, operation: "network*", filter: path_filter(path, type)
end

#allow_process_exec(path, no_sandbox: false) ⇒ void

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

This method returns an undefined value.

Parameters:



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# File 'sandbox.rb', line 310

def allow_process_exec(path, no_sandbox: false)
  modifier = "no-sandbox" if no_sandbox
  add_rule allow: true, operation: "process-exec", filter: path_filter(path, :literal), modifier:
end

#allow_read(path:, type: :literal) ⇒ void

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

This method returns an undefined value.

Parameters:



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# File 'sandbox.rb', line 305

def allow_read(path:, type: :literal)
  add_rule allow: true, operation: "file-read*", filter: path_filter(path, type)
end

#allow_read_if_exists(path:, type: :literal) ⇒ void

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

This method returns an undefined value.

Parameters:



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# File 'sandbox.rb', line 453

def allow_read_if_exists(path:, type: :literal)
  return unless path
  return unless File.exist?(path)

  allow_read path:, type:
end

#allow_write(path:, type: :literal) ⇒ void

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

This method returns an undefined value.

Parameters:



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# File 'sandbox.rb', line 461

def allow_write(path:, type: :literal)
  add_rule allow: true, operation: "file-write*", filter: path_filter(path, type)
  add_rule allow: true, operation: "file-write-setugid", filter: path_filter(path, type)
  add_rule allow: true, operation: "file-write-mode", filter: path_filter(path, type)
end

#allow_write_cellar(formula) ⇒ void

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

This method returns an undefined value.

Parameters:



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# File 'sandbox.rb', line 516

def allow_write_cellar(formula)
  allow_write_path formula.rack
  allow_write_path formula.etc
  allow_write_path formula.var
end

#allow_write_log(formula) ⇒ void

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

This method returns an undefined value.

Parameters:



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# File 'sandbox.rb', line 526

def allow_write_log(formula)
  allow_write_path formula.logs
end

#allow_write_path(path) ⇒ void

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

This method returns an undefined value.

Parameters:



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# File 'sandbox.rb', line 473

def allow_write_path(path)
  allow_write path:, type: :subpath
end

#allow_write_path_if_exists(path) ⇒ void

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

This method returns an undefined value.

Parameters:



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# File 'sandbox.rb', line 478

def allow_write_path_if_exists(path)
  return unless path
  return unless File.exist?(path)

  allow_write_path path
end

#allow_write_temp_and_cache ⇒ void

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

This method returns an undefined value.



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# File 'sandbox.rb', line 491

def allow_write_temp_and_cache
  allow_write_path HOMEBREW_TEMP
  allow_write_path HOMEBREW_CACHE
end

#allow_write_xcode ⇒ void

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

This method returns an undefined value.



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# File 'sandbox.rb', line 523

def allow_write_xcode; end

#copy_pty_output(controller) ⇒ void

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

This method returns an undefined value.

Parameters:

  • controller (IO) 


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# File 'sandbox.rb', line 684

def copy_pty_output(controller)
  controller.each_char { |c| print(c) }
rescue Errno::EIO
  # Linux marks a PTY as an I/O error when its peer closes, so treat this as EOF:
  # https://github.com/torvalds/linux/blob/master/drivers/tty/pty.c
end

#deny_all_network ⇒ void

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

This method returns an undefined value.



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# File 'sandbox.rb', line 547

def deny_all_network
  add_rule allow: false, operation: "network*"
end

#deny_read(path:, type: :literal) ⇒ void

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

This method returns an undefined value.

Parameters:



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# File 'sandbox.rb', line 316

def deny_read(path:, type: :literal)
  add_rule allow: false, operation: "file-read*", filter: path_filter(path, type)
end

#deny_read_home ⇒ void

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

This method returns an undefined value.



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# File 'sandbox.rb', line 326

def deny_read_home
  require "trust"

  home = Pathname(Dir.home(ENV.fetch("USER"))).realpath
  readable_paths = [
    HOMEBREW_PREFIX,
    HOMEBREW_REPOSITORY,
    HOMEBREW_CACHE,
    HOMEBREW_LOGS,
    HOMEBREW_TEMP,
    ENV.fetch("GITHUB_WORKSPACE", nil),
    ENV.fetch("RUNNER_WORKSPACE", nil),
    ENV.fetch("RUNNER_TEMP", nil),
    Homebrew::Trust.trust_file,
    *home_write_paths.select { |path| File.exist?(path) },
  ].compact.flat_map do |path|
    path = Pathname(path)
    [path.expand_path, (path.realpath if path.exist?)].compact
  end
  if readable_paths.any? { |path| path.ascend.include?(home) }
    # When Homebrew or CI needs some `$HOME` paths to stay readable, deny only
    # well-known credential and personal-data paths instead of enumerating all
    # of `$HOME`.
    [
      ".ssh",
      ".aws",
      ".azure",
      ".boto",
      ".docker",
      ".config/fish",
      ".config/gh",
      ".config/gcloud",
      ".config/huggingface",
      ".config/pip",
      ".config/pypoetry",
      ".config/rclone",
      ".config/containers/auth.json",
      ".config/composer/auth.json",
      ".config/sops/age/keys.txt",
      ".gnupg",
      ".git-credentials",
      ".gitconfig",
      ".gsutil",
      ".kube",
      ".netrc",
      ".npmrc",
      ".yarnrc",
      ".yarnrc.yml",
      ".pnpmrc",
      ".bunfig.toml",
      ".pypirc",
      ".pip",
      ".poetry",
      ".local/share/pypoetry",
      ".gem/credentials",
      ".bundle/config",
      ".cargo/credentials",
      ".cargo/credentials.toml",
      ".composer/auth.json",
      ".condarc",
      ".m2/settings.xml",
      ".gradle/gradle.properties",
      ".sbt/1.0/credentials.sbt",
      ".terraform.d/credentials.tfrc.json",
      ".pulumi/credentials.json",
      ".oci/config",
      ".huggingface/token",
      ".cache/huggingface/token",
      ".claude",
      ".claude.json",
      ".kiro",
      ".bash_login",
      ".bash_logout",
      ".bash_profile",
      ".bashrc",
      ".bash_history",
      ".profile",
      ".zlogin",
      ".zlogout",
      ".zprofile",
      ".zshenv",
      ".zshrc",
      ".zsh_history",
      ".python_history",
      ".mysql_history",
      ".psql_history",
      ".env",
      ".env.local",
      "Documents",
      "Movies",
      "Music",
      "Pictures",
      "Library/Keychains",
      "Library/Mobile Documents",
      "Library/CloudStorage",
      "Dropbox",
      "Google Drive",
      "OneDrive",
    ].each do |path|
      path = home/path
      next unless path.exist?

      path = path.realpath
      next unless path.ascend.include?(home)

      if (readable_path = readable_paths.find { |required_path| required_path.ascend.include?(path) })
        opoo <<~EOS
          The sandbox cannot prevent formulae from reading:
            #{path}
          because this required path is inside it:
            #{readable_path}
          Formulae may access personal data in this directory.
        EOS
        next
      end

      deny_read_path path
    rescue Errno::ENOENT
      nil
    end
    return
  end

  deny_read_path home
end

#deny_read_path(path) ⇒ void

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

This method returns an undefined value.

Parameters:



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# File 'sandbox.rb', line 321

def deny_read_path(path)
  deny_read path:, type: :subpath
end

#deny_write(path:, type: :literal) ⇒ void

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

This method returns an undefined value.

Parameters:



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# File 'sandbox.rb', line 468

def deny_write(path:, type: :literal)
  add_rule allow: false, operation: "file-write*", filter: path_filter(path, type)
end

#deny_write_homebrew_repository ⇒ void

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

This method returns an undefined value.



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# File 'sandbox.rb', line 531

def deny_write_homebrew_repository
  deny_write path: HOMEBREW_ORIGINAL_BREW_FILE
  if HOMEBREW_PREFIX.to_s == HOMEBREW_REPOSITORY.to_s
    deny_write_path HOMEBREW_LIBRARY
    deny_write_path HOMEBREW_REPOSITORY/".git"
  else
    deny_write_path HOMEBREW_REPOSITORY
  end
end

#deny_write_path(path) ⇒ void

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

This method returns an undefined value.

Parameters:



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# File 'sandbox.rb', line 486

def deny_write_path(path)
  deny_write path:, type: :subpath
end

#path_filter(path, type) ⇒ SandboxPathFilter

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

Parameters:

Returns:

  • (SandboxPathFilter) 


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# File 'sandbox.rb', line 665

def path_filter(path, type)
  # Any character is allowed: the OS-specific renderer quotes paths safely
  # (the seatbelt renderer escapes the `"` and `\` string delimiters; the
  # Linux sandbox passes each path as a separate argument), so even paths
  # with spaces, parentheses, quotes, backslashes or newlines are expressible.
  filter_path = case type
  when :regex   then path.to_s
  when :subpath, :literal
    expand_realpath(Pathname.new(path)).to_s
  else raise ArgumentError, "Invalid path filter type: #{type}"
  end

  SandboxPathFilter.new(path: filter_path, type:)
end

#record_log(file) ⇒ void

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

This method returns an undefined value.

Parameters:



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# File 'sandbox.rb', line 291

def record_log(file)
  @logfile = file
end

#run(*args) ⇒ void

This method is part of a private API. This method may only be used in the Homebrew/brew repository. Third parties should avoid using this method if possible, as it may be removed or changed without warning.

This method returns an undefined value.

Parameters:



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# File 'sandbox.rb', line 552

def run(*args)
  Dir.mktmpdir("homebrew-sandbox", HOMEBREW_TEMP) do |tmpdir|
    allow_network path: File.join(tmpdir, "socket"), type: :literal if allow_network_for_error_pipe?
    @start = T.let(Time.now, T.nilable(Time))

    begin
      command = sandbox_command(args, tmpdir)
      # Start sandbox in a pseudoterminal to prevent access of the parent terminal.
      PTY.open do |controller, worker|
        # Set the PTY's window size to match the parent terminal.
        # Some formula tests are sensitive to the terminal size and fail if this is not set.
        winch = proc do |_sig|
          controller.winsize = if $stdout.tty?
            # We can only use IO#winsize if the IO object is a TTY.
            $stdout.winsize
          else
            # Otherwise, default to tput, if available.
            # This relies on ncurses rather than the system's ioctl.
            [Utils.popen_read("tput", "lines").to_i, Utils.popen_read("tput", "cols").to_i]
          end
        end

        write_to_pty = proc do
          # Don't hang if stdin is not able to be used - throw EIO instead.
          old_ttin = trap(:TTIN, "IGNORE")

          # Update the window size whenever the parent terminal's window size changes.
          old_winch = trap(:WINCH, &winch)
          winch.call(nil)

          stdin_thread = Thread.new do
            IO.copy_stream($stdin, controller)
          rescue Errno::EIO
            # stdin is unavailable - move on.
          end

          stdout_thread = Thread.new do
            copy_pty_output(controller)
          end

          Utils.safe_fork(directory: tmpdir, yield_parent: true) do |error_pipe|
            if error_pipe
              # Child side
              Process.setsid
              controller.close
              worker.ioctl(self.class.terminal_ioctl_request, 0) # Make this the controlling terminal.

              ensure_child_tty_available

              # Move into a non-denied directory before `exec` so subsequent
              # `getcwd(3)` calls (which walk every parent) never cross a
              # `deny_read_home` path inherited from the caller's CWD.
              Dir.chdir(tmpdir)

              worker.close_on_exec = true
              apply_sandbox
              exec(*command, in: worker, out: worker, err: worker) # And map everything to the PTY.
            else
              # Parent side
              worker.close
            end
          end
        rescue ChildProcessError => e
          raise ErrorDuringExecution.new(command, status: e.status)
        ensure
          stdin_thread&.kill
          stdout_thread&.kill
          trap(:TTIN, old_ttin)
          trap(:WINCH, old_winch)
        end

        if $stdin.tty?
          # If stdin is a TTY, set it to a raw, passthrough mode while we
          # copy the input/output of the process spawned in the PTY, then
          # restore its original state afterwards. Keep `opost` set, unlike
          # `IO#raw`: clearing it stops LF -> CRLF translation for the whole
          # terminal, so anything written outside the PTY meanwhile (e.g.
          # our own `$stdout` when piped) renders staircased — and set the
          # mode in one `stty` call so there is no window where `opost` is
          # clear.
          begin
            # Ignore SIGTTOU as setting raw mode will hang if the process is in the background.
            old_ttou = trap(:TTOU, "IGNORE")
            if (tty_state = Sandbox.tty_state)
              begin
                # `-echo` matches `IO#raw`; `stty raw` alone leaves echo on.
                Utils.popen_read("stty", "raw", "-echo", "opost")
                write_to_pty.call
              ensure
                Utils.popen_read("stty", tty_state)
              end
            else
              # Cannot get the terminal state, so don't change it either.
              write_to_pty.call
            end
          ensure
            trap(:TTOU, old_ttou)
          end
        else
          write_to_pty.call
        end
      end
    rescue
      @failed = true
      raise
    ensure
      record_sandbox_log
    end
  end
end