Class: Console1984::CommandExecutor

Inherits:
Object
  • Object
show all
Includes:
Freezeable
Defined in:
lib/console1984/command_executor.rb

Overview

Supervise execution of console commands:

  • It will validate commands before running them.

  • It will execute the commands in protected mode if needed.

  • It will log the command execution, and flag suspicious attempts and forbidden commands appropriately.

Instance Attribute Summary collapse

Instance Method Summary collapse

Methods included from Freezeable

freeze_all, included

Instance Attribute Details

#last_suspicious_command_error ⇒ Object (readonly)

Returns the value of attribute last_suspicious_command_error.



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# File 'lib/console1984/command_executor.rb', line 13

def last_suspicious_command_error
  @last_suspicious_command_error
end

Instance Method Details

#execute(commands, &block) ⇒ Object

Logs and validates commands, and executes the passed block in a protected environment.

Suspicious commands will be executed but flagged as suspicious. Forbidden commands will be prevented and flagged too.



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# File 'lib/console1984/command_executor.rb', line 19

def execute(commands, &block)
  run_as_system { session_logger.before_executing commands }
  validate_command commands
  execute_in_protected_mode(&block)
rescue Console1984::Errors::ForbiddenCommandAttempted, FrozenError => error
  flag_suspicious(commands, error: error)
rescue Console1984::Errors::SuspiciousCommandAttempted => error
  flag_suspicious(commands, error: error)
  execute_in_protected_mode(&block)
rescue Console1984::Errors::ForbiddenCommandExecuted => error
  # We detected that a forbidden command was executed. We exit IRB right away.
  flag_suspicious(commands, error: error)
  Console1984.supervisor.exit_irb
rescue => error
  raise encrypting_error(error)
ensure
  run_as_system { session_logger.after_executing commands }
end

#execute_in_protected_mode(&block) ⇒ Object

Executes the passed block in protected mode.

See Console1984::Shield::Modes.



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# File 'lib/console1984/command_executor.rb', line 41

def execute_in_protected_mode(&block)
  run_as_user do
    shield.with_protected_mode(&block)
  end
end

#executing_user_command? ⇒ Boolean

Returns whether the system is currently executing a user command.

Returns:

  • (Boolean) 


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# File 'lib/console1984/command_executor.rb', line 64

def executing_user_command?
  @executing_user_command
end

#from_irb?(backtrace) ⇒ Boolean

Returns:

  • (Boolean) 


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# File 'lib/console1984/command_executor.rb', line 75

def from_irb?(backtrace)
  executing_user_command? && backtrace.first.to_s =~ /^[^\/]/
end

#run_as_system(&block) ⇒ Object

Executes the passed block as the system.

While the block is being executed, #executing_user_command? will return false.



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# File 'lib/console1984/command_executor.rb', line 59

def run_as_system(&block)
  run_command false, &block
end

#run_as_user(&block) ⇒ Object

Executes the passed block as a user.

While the block is being executed, #executing_user_command? will return true. This method helps implementing certain protection mechanisms that should only act with user commands.



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# File 'lib/console1984/command_executor.rb', line 52

def run_as_user(&block)
  run_command true, &block
end

#validate_command(command) ⇒ Object

Validates the command.

See Console1984::CommandValidator.



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# File 'lib/console1984/command_executor.rb', line 71

def validate_command(command)
  command_validator.validate(command)
end