qemu/include/sysemu/tpm_backend.h
Markus Armbruster 00bbf50a50 tpm: Clean up model registration & lookup
We have a strict separation between enum TpmModel and tpm_models[]:

* TpmModel may have any number of members.  It just happens to have one.

* tpm_register_model() uses the first empty slot in tpm_models[].

  If you register more than tpm_models[] has space,
  tpn_register_model() fails.  Its caller silently ignores the
  failure.

  Register the same TpmModel more than once has no effect other than
  wasting tpm_models[] slots: tpm_model_is_registered() is happy with
  the first one it finds.

Since we only ever register one model, and tpm_models[] has space for
just that one, this contraption even works.

Turn tpm_models[] into a straight map from enum TpmType to bool.  Much
simpler.

Cc: Stefan Berger <stefanb@us.ibm.com>
Signed-off-by: Markus Armbruster <armbru@redhat.com>
Message-Id: <1503564371-26090-5-git-send-email-armbru@redhat.com>
Reviewed-by: Marc-André Lureau <marcandre.lureau@redhat.com>
[Commit message typo fixed]
2017-09-04 13:09:13 +02:00

233 lines
5.5 KiB
C

/*
* QEMU TPM Backend
*
* Copyright IBM, Corp. 2013
*
* Authors:
* Stefan Berger <stefanb@us.ibm.com>
*
* This work is licensed under the terms of the GNU GPL, version 2 or later.
* See the COPYING file in the top-level directory.
*/
#ifndef TPM_BACKEND_H
#define TPM_BACKEND_H
#include "qom/object.h"
#include "qemu-common.h"
#include "qapi-types.h"
#include "qemu/option.h"
#include "sysemu/tpm.h"
#define TYPE_TPM_BACKEND "tpm-backend"
#define TPM_BACKEND(obj) \
OBJECT_CHECK(TPMBackend, (obj), TYPE_TPM_BACKEND)
#define TPM_BACKEND_GET_CLASS(obj) \
OBJECT_GET_CLASS(TPMBackendClass, (obj), TYPE_TPM_BACKEND)
#define TPM_BACKEND_CLASS(klass) \
OBJECT_CLASS_CHECK(TPMBackendClass, (klass), TYPE_TPM_BACKEND)
typedef struct TPMBackendClass TPMBackendClass;
typedef struct TPMBackend TPMBackend;
typedef struct TPMDriverOps TPMDriverOps;
struct TPMBackendClass {
ObjectClass parent_class;
const TPMDriverOps *ops;
void (*opened)(TPMBackend *s, Error **errp);
};
struct TPMBackend {
Object parent;
/*< protected >*/
bool opened;
char *id;
enum TpmModel fe_model;
char *path;
char *cancel_path;
const TPMDriverOps *ops;
QLIST_ENTRY(TPMBackend) list;
};
typedef void (TPMRecvDataCB)(TPMState *, uint8_t locty, bool selftest_done);
typedef struct TPMSizedBuffer {
uint32_t size;
uint8_t *buffer;
} TPMSizedBuffer;
struct TPMDriverOps {
enum TpmType type;
const QemuOptDesc *opts;
/* get a descriptive text of the backend to display to the user */
const char *(*desc)(void);
TPMBackend *(*create)(QemuOpts *opts, const char *id);
void (*destroy)(TPMBackend *t);
/* initialize the backend */
int (*init)(TPMBackend *t, TPMState *s, TPMRecvDataCB *datacb);
/* start up the TPM on the backend */
int (*startup_tpm)(TPMBackend *t);
/* returns true if nothing will ever answer TPM requests */
bool (*had_startup_error)(TPMBackend *t);
size_t (*realloc_buffer)(TPMSizedBuffer *sb);
void (*deliver_request)(TPMBackend *t);
void (*reset)(TPMBackend *t);
void (*cancel_cmd)(TPMBackend *t);
bool (*get_tpm_established_flag)(TPMBackend *t);
int (*reset_tpm_established_flag)(TPMBackend *t, uint8_t locty);
TPMVersion (*get_tpm_version)(TPMBackend *t);
};
/**
* tpm_backend_get_type:
* @s: the backend
*
* Returns the TpmType of the backend.
*/
enum TpmType tpm_backend_get_type(TPMBackend *s);
/**
* tpm_backend_get_desc:
* @s: the backend
*
* Returns a human readable description of the backend.
*/
const char *tpm_backend_get_desc(TPMBackend *s);
/**
* tpm_backend_destroy:
* @s: the backend to destroy
*/
void tpm_backend_destroy(TPMBackend *s);
/**
* tpm_backend_init:
* @s: the backend to initialized
* @state: TPMState
* @datacb: callback for sending data to frontend
*
* Initialize the backend with the given variables.
*
* Returns 0 on success.
*/
int tpm_backend_init(TPMBackend *s, TPMState *state,
TPMRecvDataCB *datacb);
/**
* tpm_backend_startup_tpm:
* @s: the backend whose TPM support is to be started
*
* Returns 0 on success.
*/
int tpm_backend_startup_tpm(TPMBackend *s);
/**
* tpm_backend_had_startup_error:
* @s: the backend to query for a statup error
*
* Check whether the backend had an error during startup. Returns
* false if no error occurred and the backend can be used, true
* otherwise.
*/
bool tpm_backend_had_startup_error(TPMBackend *s);
/**
* tpm_backend_realloc_buffer:
* @s: the backend
* @sb: the TPMSizedBuffer to re-allocated to the size suitable for the
* backend.
*
* This function returns the size of the allocated buffer
*/
size_t tpm_backend_realloc_buffer(TPMBackend *s, TPMSizedBuffer *sb);
/**
* tpm_backend_deliver_request:
* @s: the backend to send the request to
*
* Send a request to the backend. The backend will then send the request
* to the TPM implementation.
*/
void tpm_backend_deliver_request(TPMBackend *s);
/**
* tpm_backend_reset:
* @s: the backend to reset
*
* Reset the backend into a well defined state with all previous errors
* reset.
*/
void tpm_backend_reset(TPMBackend *s);
/**
* tpm_backend_cancel_cmd:
* @s: the backend
*
* Cancel any ongoing command being processed by the TPM implementation
* on behalf of the QEMU guest.
*/
void tpm_backend_cancel_cmd(TPMBackend *s);
/**
* tpm_backend_get_tpm_established_flag:
* @s: the backend
*
* Get the TPM establishment flag. This function may be called very
* frequently by the frontend since for example in the TIS implementation
* this flag is part of a register.
*/
bool tpm_backend_get_tpm_established_flag(TPMBackend *s);
/**
* tpm_backend_reset_tpm_established_flag:
* @s: the backend
* @locty: the locality number
*
* Reset the TPM establishment flag.
*/
int tpm_backend_reset_tpm_established_flag(TPMBackend *s, uint8_t locty);
/**
* tpm_backend_open:
* @s: the backend to open
* @errp: a pointer to return the #Error object if an error occurs.
*
* This function will open the backend if it is not already open. Calling this
* function on an already opened backend will not result in an error.
*/
void tpm_backend_open(TPMBackend *s, Error **errp);
/**
* tpm_backend_get_tpm_version:
* @s: the backend to call into
*
* Get the TPM Version that is emulated at the backend.
*
* Returns TPMVersion.
*/
TPMVersion tpm_backend_get_tpm_version(TPMBackend *s);
TPMBackend *qemu_find_tpm(const char *id);
const TPMDriverOps *tpm_get_backend_driver(const char *type);
void tpm_register_model(enum TpmModel model);
void tpm_register_driver(const TPMDriverOps *tdo);
#endif