This change introduces a new TPM backend driver that can communicate with
swtpm(software TPM emulator) using unix domain socket interface. QEMU talks to
the TPM emulator using QEMU's socket-based chardev backend device.
Swtpm uses two Unix sockets for communications, one for plain TPM commands and
responses, and one for out-of-band control messages. QEMU passes the data
socket to be used over the control channel.
The swtpm and associated tools can be found here:
https://github.com/stefanberger/swtpm
The swtpm's control channel protocol specification can be found here:
https://github.com/stefanberger/swtpm/wiki/Control-Channel-Specification
Usage:
# setup TPM state directory
mkdir /tmp/mytpm
chown -R tss:root /tmp/mytpm
/usr/bin/swtpm_setup --tpm-state /tmp/mytpm --createek
# Ask qemu to use TPM emulator with given tpm state directory
qemu-system-x86_64 \
[...] \
-chardev socket,id=chrtpm,path=/tmp/swtpm-sock \
-tpmdev emulator,id=tpm0,chardev=chrtpm \
-device tpm-tis,tpmdev=tpm0 \
[...]
Signed-off-by: Amarnath Valluri <amarnath.valluri@intel.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
Tested-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
In the TPM passthrough backend driver, modify the probing code so
that we can check whether a TPM 1.2 or TPM 2 is being used
and adapt the behavior of the TPM TIS accordingly.
Move the code that tested for a TPM 1.2 into tpm_utils.c
and extend it with test for probing for TPM 2. Have the
function return the version of TPM found.
Signed-off-by: Stefan Berger <stefanb@linux.vnet.ibm.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
The TPM subsystem does not have a full front-end/back-end separation.
The sole available backend, tpm_passthrough, depends on the data
structures of the sole available frontend, tpm_tis.
However, we can at least try to split the user interface (tpm.c) from the
implementation (hw/tpm). The patches makes tpm.c not include tpm_int.h,
which is shared between tpm_tis.c and tpm_passthrough.c; instead it
moves more stuff to tpm_backend.h.
Signed-off-by: Paolo Bonzini <pbonzini@redhat.com>
