tpm: Add TPM2 support for read/write values

Implement this API function for TPM2.

Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
This commit is contained in:
Simon Glass 2021-02-06 14:23:40 -07:00 committed by Tom Rini
parent eadcbc7896
commit 6719cbe31a
4 changed files with 127 additions and 2 deletions

View File

@ -55,6 +55,8 @@ enum tpm_version {
* @buf: Buffer used during the exchanges with the chip
* @pcr_count: Number of PCR per bank
* @pcr_select_min: Minimum size in bytes of the pcrSelect array
* @plat_hier_disabled: Platform hierarchy has been disabled (TPM is locked
* down until next reboot)
*/
struct tpm_chip_priv {
enum tpm_version version;
@ -66,6 +68,7 @@ struct tpm_chip_priv {
/* TPM v2 specific data */
uint pcr_count;
uint pcr_select_min;
bool plat_hier_disabled;
};
/**

View File

@ -242,6 +242,7 @@ enum tpm2_command_codes {
TPM2_CC_HIERCHANGEAUTH = 0x0129,
TPM2_CC_NV_DEFINE_SPACE = 0x012a,
TPM2_CC_PCR_SETAUTHPOL = 0x012C,
TPM2_CC_NV_WRITE = 0x0137,
TPM2_CC_DAM_RESET = 0x0139,
TPM2_CC_DAM_PARAMETERS = 0x013A,
TPM2_CC_NV_READ = 0x014E,
@ -356,6 +357,20 @@ enum {
TPM_MAX_BUF_SIZE = 1260,
};
enum {
/* Secure storage for firmware settings */
TPM_HT_PCR = 0,
TPM_HT_NV_INDEX,
TPM_HT_HMAC_SESSION,
TPM_HT_POLICY_SESSION,
HR_SHIFT = 24,
HR_PCR = TPM_HT_PCR << HR_SHIFT,
HR_HMAC_SESSION = TPM_HT_HMAC_SESSION << HR_SHIFT,
HR_POLICY_SESSION = TPM_HT_POLICY_SESSION << HR_SHIFT,
HR_NV_INDEX = TPM_HT_NV_INDEX << HR_SHIFT,
};
/**
* Issue a TPM2_Startup command.
*
@ -420,6 +435,29 @@ u32 tpm2_nv_define_space(struct udevice *dev, u32 space_index,
u32 tpm2_pcr_extend(struct udevice *dev, u32 index, u32 algorithm,
const u8 *digest, u32 digest_len);
/**
* Read data from the secure storage
*
* @dev TPM device
* @index Index of data to read
* @data Place to put data
* @count Number of bytes of data
* @return code of the operation
*/
u32 tpm2_nv_read_value(struct udevice *dev, u32 index, void *data, u32 count);
/**
* Write data to the secure storage
*
* @dev TPM device
* @index Index of data to write
* @data Data to write
* @count Number of bytes of data
* @return code of the operation
*/
u32 tpm2_nv_write_value(struct udevice *dev, u32 index, const void *data,
u32 count);
/**
* Issue a TPM2_PCR_Read command.
*

View File

@ -169,6 +169,90 @@ u32 tpm2_pcr_extend(struct udevice *dev, u32 index, u32 algorithm,
return tpm_sendrecv_command(dev, command_v2, NULL, NULL);
}
u32 tpm2_nv_read_value(struct udevice *dev, u32 index, void *data, u32 count)
{
u8 command_v2[COMMAND_BUFFER_SIZE] = {
/* header 10 bytes */
tpm_u16(TPM2_ST_SESSIONS), /* TAG */
tpm_u32(10 + 8 + 4 + 9 + 4), /* Length */
tpm_u32(TPM2_CC_NV_READ), /* Command code */
/* handles 8 bytes */
tpm_u32(TPM2_RH_PLATFORM), /* Primary platform seed */
tpm_u32(HR_NV_INDEX + index), /* Password authorisation */
/* AUTH_SESSION */
tpm_u32(9), /* Authorization size */
tpm_u32(TPM2_RS_PW), /* Session handle */
tpm_u16(0), /* Size of <nonce> */
/* <nonce> (if any) */
0, /* Attributes: Cont/Excl/Rst */
tpm_u16(0), /* Size of <hmac/password> */
/* <hmac/password> (if any) */
tpm_u16(count), /* Number of bytes */
tpm_u16(0), /* Offset */
};
size_t response_len = COMMAND_BUFFER_SIZE;
u8 response[COMMAND_BUFFER_SIZE];
int ret;
u16 tag;
u32 size, code;
ret = tpm_sendrecv_command(dev, command_v2, response, &response_len);
if (ret)
return log_msg_ret("read", ret);
if (unpack_byte_string(response, response_len, "wdds",
0, &tag, 2, &size, 6, &code,
16, data, count))
return TPM_LIB_ERROR;
return 0;
}
u32 tpm2_nv_write_value(struct udevice *dev, u32 index, const void *data,
u32 count)
{
struct tpm_chip_priv *priv = dev_get_uclass_priv(dev);
uint offset = 10 + 8 + 4 + 9 + 2;
uint len = offset + count + 2;
/* Use empty password auth if platform hierarchy is disabled */
u32 auth = priv->plat_hier_disabled ? HR_NV_INDEX + index :
TPM2_RH_PLATFORM;
u8 command_v2[COMMAND_BUFFER_SIZE] = {
/* header 10 bytes */
tpm_u16(TPM2_ST_SESSIONS), /* TAG */
tpm_u32(len), /* Length */
tpm_u32(TPM2_CC_NV_WRITE), /* Command code */
/* handles 8 bytes */
tpm_u32(auth), /* Primary platform seed */
tpm_u32(HR_NV_INDEX + index), /* Password authorisation */
/* AUTH_SESSION */
tpm_u32(9), /* Authorization size */
tpm_u32(TPM2_RS_PW), /* Session handle */
tpm_u16(0), /* Size of <nonce> */
/* <nonce> (if any) */
0, /* Attributes: Cont/Excl/Rst */
tpm_u16(0), /* Size of <hmac/password> */
/* <hmac/password> (if any) */
tpm_u16(count),
};
size_t response_len = COMMAND_BUFFER_SIZE;
u8 response[COMMAND_BUFFER_SIZE];
int ret;
ret = pack_byte_string(command_v2, sizeof(command_v2), "sw",
offset, data, count,
offset + count, 0);
if (ret)
return TPM_LIB_ERROR;
return tpm_sendrecv_command(dev, command_v2, response, &response_len);
}
u32 tpm2_pcr_read(struct udevice *dev, u32 idx, unsigned int idx_min_sz,
void *data, unsigned int *updates)
{

View File

@ -118,7 +118,7 @@ u32 tpm_nv_read_value(struct udevice *dev, u32 index, void *data, u32 count)
if (is_tpm1(dev))
return tpm1_nv_read_value(dev, index, data, count);
else if (is_tpm2(dev))
return -ENOSYS;
return tpm2_nv_read_value(dev, index, data, count);
else
return -ENOSYS;
}
@ -129,7 +129,7 @@ u32 tpm_nv_write_value(struct udevice *dev, u32 index, const void *data,
if (is_tpm1(dev))
return tpm1_nv_write_value(dev, index, data, count);
else if (is_tpm2(dev))
return -ENOSYS;
return tpm2_nv_write_value(dev, index, data, count);
else
return -ENOSYS;
}