blob: ca1caec113f0632058d85b116de52682ff15abd1 [file] [log] [blame]
/*
* SPAPR TPM Proxy/Hypercall
*
* Copyright IBM Corp. 2019
*
* Authors:
* Michael Roth <mdroth@linux.vnet.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.
*/
#include "qemu/osdep.h"
#include "qemu-common.h"
#include "qapi/error.h"
#include "qemu/error-report.h"
#include "sysemu/reset.h"
#include "cpu.h"
#include "hw/ppc/spapr.h"
#include "hw/qdev-properties.h"
#include "trace.h"
#define TPM_SPAPR_BUFSIZE 4096
enum {
TPM_COMM_OP_EXECUTE = 1,
TPM_COMM_OP_CLOSE_SESSION = 2,
};
static void spapr_tpm_proxy_reset(void *opaque)
{
SpaprTpmProxy *tpm_proxy = SPAPR_TPM_PROXY(opaque);
if (tpm_proxy->host_fd != -1) {
close(tpm_proxy->host_fd);
tpm_proxy->host_fd = -1;
}
}
static ssize_t tpm_execute(SpaprTpmProxy *tpm_proxy, target_ulong *args)
{
uint64_t data_in = ppc64_phys_to_real(args[1]);
target_ulong data_in_size = args[2];
uint64_t data_out = ppc64_phys_to_real(args[3]);
target_ulong data_out_size = args[4];
uint8_t buf_in[TPM_SPAPR_BUFSIZE];
uint8_t buf_out[TPM_SPAPR_BUFSIZE];
ssize_t ret;
trace_spapr_tpm_execute(data_in, data_in_size, data_out, data_out_size);
if (data_in_size > TPM_SPAPR_BUFSIZE) {
error_report("invalid TPM input buffer size: " TARGET_FMT_lu,
data_in_size);
return H_P3;
}
if (data_out_size < TPM_SPAPR_BUFSIZE) {
error_report("invalid TPM output buffer size: " TARGET_FMT_lu,
data_out_size);
return H_P5;
}
if (tpm_proxy->host_fd == -1) {
tpm_proxy->host_fd = open(tpm_proxy->host_path, O_RDWR);
if (tpm_proxy->host_fd == -1) {
error_report("failed to open TPM device %s: %d",
tpm_proxy->host_path, errno);
return H_RESOURCE;
}
}
cpu_physical_memory_read(data_in, buf_in, data_in_size);
do {
ret = write(tpm_proxy->host_fd, buf_in, data_in_size);
if (ret > 0) {
data_in_size -= ret;
}
} while ((ret >= 0 && data_in_size > 0) || (ret == -1 && errno == EINTR));
if (ret == -1) {
error_report("failed to write to TPM device %s: %d",
tpm_proxy->host_path, errno);
return H_RESOURCE;
}
do {
ret = read(tpm_proxy->host_fd, buf_out, data_out_size);
} while (ret == 0 || (ret == -1 && errno == EINTR));
if (ret == -1) {
error_report("failed to read from TPM device %s: %d",
tpm_proxy->host_path, errno);
return H_RESOURCE;
}
cpu_physical_memory_write(data_out, buf_out, ret);
args[0] = ret;
return H_SUCCESS;
}
static target_ulong h_tpm_comm(PowerPCCPU *cpu,
SpaprMachineState *spapr,
target_ulong opcode,
target_ulong *args)
{
target_ulong op = args[0];
SpaprTpmProxy *tpm_proxy = spapr->tpm_proxy;
if (!tpm_proxy) {
error_report("TPM proxy not available");
return H_FUNCTION;
}
trace_spapr_h_tpm_comm(tpm_proxy->host_path, op);
switch (op) {
case TPM_COMM_OP_EXECUTE:
return tpm_execute(tpm_proxy, args);
case TPM_COMM_OP_CLOSE_SESSION:
spapr_tpm_proxy_reset(tpm_proxy);
return H_SUCCESS;
default:
return H_PARAMETER;
}
}
static void spapr_tpm_proxy_realize(DeviceState *d, Error **errp)
{
SpaprTpmProxy *tpm_proxy = SPAPR_TPM_PROXY(d);
if (tpm_proxy->host_path == NULL) {
error_setg(errp, "must specify 'host-path' option for device");
return;
}
tpm_proxy->host_fd = -1;
qemu_register_reset(spapr_tpm_proxy_reset, tpm_proxy);
}
static void spapr_tpm_proxy_unrealize(DeviceState *d, Error **errp)
{
SpaprTpmProxy *tpm_proxy = SPAPR_TPM_PROXY(d);
qemu_unregister_reset(spapr_tpm_proxy_reset, tpm_proxy);
}
static Property spapr_tpm_proxy_properties[] = {
DEFINE_PROP_STRING("host-path", SpaprTpmProxy, host_path),
DEFINE_PROP_END_OF_LIST(),
};
static void spapr_tpm_proxy_class_init(ObjectClass *k, void *data)
{
DeviceClass *dk = DEVICE_CLASS(k);
dk->realize = spapr_tpm_proxy_realize;
dk->unrealize = spapr_tpm_proxy_unrealize;
dk->user_creatable = true;
dk->props = spapr_tpm_proxy_properties;
}
static const TypeInfo spapr_tpm_proxy_info = {
.name = TYPE_SPAPR_TPM_PROXY,
.parent = TYPE_DEVICE,
.instance_size = sizeof(SpaprTpmProxy),
.class_init = spapr_tpm_proxy_class_init,
};
static void spapr_tpm_proxy_register_types(void)
{
type_register_static(&spapr_tpm_proxy_info);
spapr_register_hypercall(SVM_H_TPM_COMM, h_tpm_comm);
}
type_init(spapr_tpm_proxy_register_types)