memflow-qemu

The qemu connector implements a memflow plugin interface for Qemu on top of the Process Filesystem on Linux.

Compilation

Installing the library

The recommended way to install memflow connectors is using memflowup.

Development builds

To compile the connector as dynamic library to be used with the memflow plugin system use the following command:

cargo build --release --all-features

The plugin can then be found in the target/release/ directory and has to be copied to one of memflows default search paths.

Linking the crate statically in a rust project

To use the connector in a rust project just include it in your Cargo.toml

memflow-qemu = "^0.2.0-beta"

Arguments

The target argument specifies the name of the qemu virtual machine (specified with -name when starting qemu).

The following additional arguments can be used when loading the connector:

• map_base - overrides the default VM memory base (optional)
• map_size - overrides the default VM memory size (optional)

Permissions

The qemu connector requires access to the qemu process via the linux procfs. This means any process which loads this connector requires to have at least ptrace permissions set.

To set ptrace permissions on a binary simply use:

sudo setcap 'CAP_SYS_PTRACE=ep' [filename]

Alternatively you can just run the binary via sudo.

Memory Mappings

The connector supports dynamic acquisition of the qemu memory mappings by utilizing the qemu qmp protocol.

To enable qmp on a virtual machine simply add this to the qemu command line:

-qmp unix:/tmp/qmp-my-vm.sock,server,nowait

Alternatively a tcp server can be exposed:

-qmp tcp:localhost:12345,server,nowait

Or via libvirt:

<domain xmlns:qemu="http://libvirt.org/schemas/domain/qemu/1.0" type="kvm">

...

  </devices>
  <qemu:commandline>
    <qemu:arg value="-qmp"/>
    <qemu:arg value="unix:/tmp/qmp-my-vm.sock,server,nowait"/>
  </qemu:commandline>
</domain>

Please refer to the qemu qmp manual for more information about how to configure this feature.

In case qmp is not active or could not be fetched, the connector falls back to hard-coded mapping tables for specific qemu machine types.

Running Examples

Analog to the examples found in the main memflow repository examples can be run via:

RUST_SETPTRACE=1 cargo run --example read_phys --release
RUST_SETPTRACE=1 cargo run --example ps_win32 --release
RUST_SETPTRACE=1 cargo run --example ps_inventory --release

For more information about RUST_SETPTRACE and how to run examples see the running-examples section in the main memflow repository.

License

Licensed under MIT License, see LICENSE.

Contribution

Unless you explicitly state otherwise, any contribution intentionally submitted for inclusion in the work by you, shall be licensed as above, without any additional terms or conditions.