blob: 2bc7dc87ed30013f703412c8daa5a6d29bdcf452 [file] [log] [blame]
// SPDX-License-Identifier: GPL-2.0+
/*
* Copyright (c) 2013 Google, Inc
*/
#include <display_options.h>
#include <dm.h>
#include <tpm-v1.h>
#include <asm/state.h>
#include <asm/unaligned.h>
#include <u-boot/crc.h>
#include "sandbox_common.h"
#define NV_DATA_PUBLIC_PERMISSIONS_OFFSET 60
/*
* Information about our TPM emulation. This is preserved in the sandbox
* state file if enabled.
*/
static struct tpm_state {
bool valid;
struct nvdata_state nvdata[NV_SEQ_COUNT];
} s_state, *g_state;
/**
* sandbox_tpm_read_state() - read the sandbox EC state from the state file
*
* If data is available, then blob and node will provide access to it. If
* not this function sets up an empty TPM.
*
* @blob: Pointer to device tree blob, or NULL if no data to read
* @node: Node offset to read from
*/
static int sandbox_tpm_read_state(const void *blob, int node)
{
struct tpm_state *state = &s_state;
const char *prop;
int len;
int i;
if (!blob)
return 0;
for (i = 0; i < NV_SEQ_COUNT; i++) {
struct nvdata_state *nvd = &state->nvdata[i];
char prop_name[20];
sprintf(prop_name, "nvdata%d", i);
prop = fdt_getprop(blob, node, prop_name, &len);
if (len >= NV_DATA_SIZE)
return log_msg_ret("nvd", -E2BIG);
if (prop) {
memcpy(nvd->data, prop, len);
nvd->length = len;
nvd->present = true;
}
}
s_state.valid = true;
return 0;
}
/**
* sandbox_tpm_write_state() - Write out our state to the state file
*
* The caller will ensure that there is a node ready for the state. The node
* may already contain the old state, in which case it is overridden.
*
* @blob: Device tree blob holding state
* @node: Node to write our state into
*/
static int sandbox_tpm_write_state(void *blob, int node)
{
const struct tpm_state *state = g_state;
int i;
if (!state)
return 0;
/*
* We are guaranteed enough space to write basic properties.
* We could use fdt_add_subnode() to put each set of data in its
* own node - perhaps useful if we add access informaiton to each.
*/
for (i = 0; i < NV_SEQ_COUNT; i++) {
const struct nvdata_state *nvd = &state->nvdata[i];
char prop_name[20];
if (nvd->present) {
snprintf(prop_name, sizeof(prop_name), "nvdata%d", i);
fdt_setprop(blob, node, prop_name, nvd->data,
nvd->length);
}
}
return 0;
}
SANDBOX_STATE_IO(sandbox_tpm, "google,sandbox-tpm", sandbox_tpm_read_state,
sandbox_tpm_write_state);
static void handle_cap_flag_space(u8 **datap, uint index)
{
struct tpm_nv_data_public pub;
/* TPM_NV_PER_PPWRITE */
memset(&pub, '\0', sizeof(pub));
pub.nv_index = __cpu_to_be32(index);
pub.pcr_info_read.pcr_selection.size_of_select = __cpu_to_be16(
sizeof(pub.pcr_info_read.pcr_selection.pcr_select));
pub.permission.attributes = __cpu_to_be32(1);
pub.pcr_info_write = pub.pcr_info_read;
memcpy(*datap, &pub, sizeof(pub));
*datap += sizeof(pub);
}
static int sandbox_tpm_xfer(struct udevice *dev, const uint8_t *sendbuf,
size_t send_size, uint8_t *recvbuf,
size_t *recv_len)
{
struct tpm_state *tpm = dev_get_priv(dev);
uint32_t code, index, length, type;
uint8_t *data;
int seq;
code = get_unaligned_be32(sendbuf + sizeof(uint16_t) +
sizeof(uint32_t));
#ifdef DEBUG
printf("tpm: %zd bytes, recv_len %zd, cmd = %x\n", send_size,
*recv_len, code);
print_buffer(0, sendbuf, 1, send_size, 0);
#endif
switch (code) {
case TPM_CMD_GET_CAPABILITY:
type = get_unaligned_be32(sendbuf + 14);
switch (type) {
case TPM_CAP_FLAG:
index = get_unaligned_be32(sendbuf + 18);
printf("Get flags index %#02x\n", index);
*recv_len = 22;
memset(recvbuf, '\0', *recv_len);
data = recvbuf + TPM_HDR_LEN + sizeof(uint32_t);
switch (index) {
case FIRMWARE_NV_INDEX:
break;
case KERNEL_NV_INDEX:
handle_cap_flag_space(&data, index);
*recv_len = data - recvbuf;
break;
case TPM_CAP_FLAG_PERMANENT: {
struct tpm_permanent_flags *pflags;
pflags = (struct tpm_permanent_flags *)data;
memset(pflags, '\0', sizeof(*pflags));
put_unaligned_be32(TPM_TAG_PERMANENT_FLAGS,
&pflags->tag);
*recv_len = TPM_HEADER_SIZE + 4 +
sizeof(*pflags);
break;
}
default:
printf(" ** Unknown flags index %x\n", index);
return -ENOSYS;
}
put_unaligned_be32(*recv_len, recvbuf + TPM_HDR_LEN);
break;
case TPM_CAP_NV_INDEX:
index = get_unaligned_be32(sendbuf + 18);
printf("Get cap nv index %#02x\n", index);
put_unaligned_be32(22, recvbuf + TPM_HDR_LEN);
break;
default:
printf(" ** Unknown 0x65 command type %#02x\n",
type);
return -ENOSYS;
}
break;
case TPM_CMD_NV_WRITE_VALUE:
index = get_unaligned_be32(sendbuf + 10);
length = get_unaligned_be32(sendbuf + 18);
seq = sb_tpm_index_to_seq(index);
if (seq < 0)
return -EINVAL;
printf("tpm: nvwrite index=%#02x, len=%#02x\n", index, length);
sb_tpm_write_data(tpm->nvdata, seq, sendbuf, 22, length);
break;
case TPM_CMD_NV_READ_VALUE: /* nvread */
index = get_unaligned_be32(sendbuf + 10);
length = get_unaligned_be32(sendbuf + 18);
seq = sb_tpm_index_to_seq(index);
if (seq < 0)
return -EINVAL;
printf("tpm: nvread index=%#02x, len=%#02x, seq=%#02x\n", index,
length, seq);
*recv_len = TPM_HDR_LEN + sizeof(uint32_t) + length;
memset(recvbuf, '\0', *recv_len);
put_unaligned_be32(length, recvbuf + TPM_HDR_LEN);
sb_tpm_read_data(tpm->nvdata, seq, recvbuf, TPM_HDR_LEN + 4,
length);
break;
case TPM_CMD_EXTEND:
*recv_len = 30;
memset(recvbuf, '\0', *recv_len);
break;
case TPM_CMD_NV_DEFINE_SPACE:
index = get_unaligned_be32(sendbuf + 12);
length = get_unaligned_be32(sendbuf + 77);
seq = sb_tpm_index_to_seq(index);
if (seq < 0)
return -EINVAL;
printf("tpm: define_space index=%#02x, len=%#02x, seq=%#02x\n",
index, length, seq);
sb_tpm_define_data(tpm->nvdata, seq, length);
*recv_len = 12;
memset(recvbuf, '\0', *recv_len);
break;
case 0x15: /* pcr read */
case 0x5d: /* force clear */
case 0x6f: /* physical enable */
case 0x72: /* physical set deactivated */
case 0x99: /* startup */
case 0x50: /* self test full */
case 0x4000000a: /* assert physical presence */
*recv_len = 12;
memset(recvbuf, '\0', *recv_len);
break;
default:
printf("Unknown tpm command %02x\n", code);
return -ENOSYS;
}
#ifdef DEBUG
printf("tpm: rx recv_len %zd\n", *recv_len);
print_buffer(0, recvbuf, 1, *recv_len, 0);
#endif
return 0;
}
static int sandbox_tpm_get_desc(struct udevice *dev, char *buf, int size)
{
if (size < 15)
return -ENOSPC;
return snprintf(buf, size, "sandbox TPM");
}
static int sandbox_tpm_probe(struct udevice *dev)
{
struct tpm_state *tpm = dev_get_priv(dev);
if (s_state.valid)
memcpy(tpm, &s_state, sizeof(*tpm));
g_state = tpm;
return 0;
}
static int sandbox_tpm_open(struct udevice *dev)
{
return 0;
}
static int sandbox_tpm_close(struct udevice *dev)
{
return 0;
}
static const struct tpm_ops sandbox_tpm_ops = {
.open = sandbox_tpm_open,
.close = sandbox_tpm_close,
.get_desc = sandbox_tpm_get_desc,
.xfer = sandbox_tpm_xfer,
};
static const struct udevice_id sandbox_tpm_ids[] = {
{ .compatible = "google,sandbox-tpm" },
{ }
};
U_BOOT_DRIVER(google_sandbox_tpm) = {
.name = "google_sandbox_tpm",
.id = UCLASS_TPM,
.of_match = sandbox_tpm_ids,
.ops = &sandbox_tpm_ops,
.probe = sandbox_tpm_probe,
.priv_auto = sizeof(struct tpm_state),
};