tpm: Add an implementation of define_space
Add support for this so that the TPM can be set up for use with
Chromium OS verified boot.
Signed-off-by: Simon Glass <sjg@chromium.org>
Acked-by: Ilias Apalodimas <ilias.apalodimas@linaro.org>
diff --git a/include/tpm-v2.h b/include/tpm-v2.h
index 56eaa65..aa8b651 100644
--- a/include/tpm-v2.h
+++ b/include/tpm-v2.h
@@ -240,6 +240,7 @@
TPM2_CC_CLEAR = 0x0126,
TPM2_CC_CLEARCONTROL = 0x0127,
TPM2_CC_HIERCHANGEAUTH = 0x0129,
+ TPM2_CC_NV_DEFINE_SPACE = 0x012a,
TPM2_CC_PCR_SETAUTHPOL = 0x012C,
TPM2_CC_DAM_RESET = 0x0139,
TPM2_CC_DAM_PARAMETERS = 0x013A,
@@ -389,6 +390,23 @@
const ssize_t pw_sz);
/**
+ * Issue a TPM_NV_DefineSpace command
+ *
+ * This allows a space to be defined with given attributes and policy
+ *
+ * @dev TPM device
+ * @space_index index of the area
+ * @space_size size of area in bytes
+ * @nv_attributes TPM_NV_ATTRIBUTES of the area
+ * @nv_policy policy to use
+ * @nv_policy_size size of the policy
+ * @return return code of the operation
+ */
+u32 tpm2_nv_define_space(struct udevice *dev, u32 space_index,
+ size_t space_size, u32 nv_attributes,
+ const u8 *nv_policy, size_t nv_policy_size);
+
+/**
* Issue a TPM2_PCR_Extend command.
*
* @dev TPM device
diff --git a/lib/tpm-v2.c b/lib/tpm-v2.c
index c4e869e..e9bf401 100644
--- a/lib/tpm-v2.c
+++ b/lib/tpm-v2.c
@@ -81,6 +81,53 @@
return tpm_sendrecv_command(dev, command_v2, NULL, NULL);
}
+u32 tpm2_nv_define_space(struct udevice *dev, u32 space_index,
+ size_t space_size, u32 nv_attributes,
+ const u8 *nv_policy, size_t nv_policy_size)
+{
+ /*
+ * Calculate the offset of the nv_policy piece by adding each of the
+ * chunks below.
+ */
+ uint offset = 10 + 8 + 13 + 14;
+ u8 command_v2[COMMAND_BUFFER_SIZE] = {
+ /* header 10 bytes */
+ tpm_u16(TPM2_ST_SESSIONS), /* TAG */
+ tpm_u32(offset + nv_policy_size),/* Length */
+ tpm_u32(TPM2_CC_NV_DEFINE_SPACE),/* Command code */
+
+ /* handles 8 bytes */
+ tpm_u32(TPM2_RH_PLATFORM), /* Primary platform seed */
+
+ /* session header 13 bytes */
+ tpm_u32(9), /* Header size */
+ tpm_u32(TPM2_RS_PW), /* Password authorisation */
+ tpm_u16(0), /* nonce_size */
+ 0, /* session_attrs */
+ tpm_u16(0), /* auth_size */
+
+ /* message 14 bytes + policy */
+ tpm_u16(12 + nv_policy_size), /* size */
+ tpm_u32(space_index),
+ tpm_u16(TPM2_ALG_SHA256),
+ tpm_u32(nv_attributes),
+ tpm_u16(nv_policy_size),
+ /* nv_policy */
+ };
+ int ret;
+
+ /*
+ * Fill the command structure starting from the first buffer:
+ * - the password (if any)
+ */
+ ret = pack_byte_string(command_v2, sizeof(command_v2), "s",
+ offset, nv_policy, nv_policy_size);
+ if (ret)
+ return TPM_LIB_ERROR;
+
+ return tpm_sendrecv_command(dev, command_v2, NULL, NULL);
+}
+
u32 tpm2_pcr_extend(struct udevice *dev, u32 index, u32 algorithm,
const u8 *digest, u32 digest_len)
{