angr.state_plugins.preconstrainer

class angr.state_plugins.preconstrainer.SimStatePreconstrainer

Bases: SimStatePlugin

This state plugin manages the concept of preconstraining - adding constraints which you would like to remove later.

Parameters:

constrained_addrs – SimActions for memory operations whose addresses should be constrained during crash analysis

__init__(constrained_addrs=None)
preconstrain(value, variable)

Add a preconstraint that variable == value to the state.

Parameters:

  • value – The concrete value. Can be a bitvector or a bytestring or an integer.

  • variable – The BVS to preconstrain.

preconstrain_file(content, simfile, set_length=False)

Preconstrain the contents of a file.

Parameters:

  • content – The content to preconstrain the file to. Can be a bytestring or a list thereof.

  • simfile – The actual simfile to preconstrain

preconstrain_flag_page(magic_content)

Preconstrain the data in the flag page.

Parameters:

magic_content – The content of the magic page as a bytestring.

remove_preconstraints(to_composite_solver=True, simplify=True)

Remove the preconstraints from the state.

If you are using the zen plugin, this will also use that to filter the constraints.

Parameters:

  • to_composite_solver – Whether to convert the replacement solver to a composite solver. You probably want this if you’re switching from tracing to symbolic analysis.

  • simplify – Whether to simplify the resulting set of constraints.

reconstrain()

Split the solver. If any of the subsolvers time out after a short timeout (10 seconds), re-add the preconstraints associated with each of its variables. Hopefully these constraints still allow us to do meaningful things to the state.