[U-Boot] [PATCH 07/17] lib: tpm: Add command to flush resources

[Mario Six]

This patch adds a function to the TPM library, which allows U-Boot to
flush resources, e.g. keys, from the TPM.

Signed-off-by: Mario Six <mario.six at gdsys.cc>
---
 board/gdsys/p1022/controlcenterd-id.c |  9 -------
 include/tpm.h                         | 45 +++++++++++++++++++++++++++++++++++
 lib/tpm.c                             | 28 ++++++++++++++++++++++
 3 files changed, 73 insertions(+), 9 deletions(-)

diff --git a/board/gdsys/p1022/controlcenterd-id.c b/board/gdsys/p1022/controlcenterd-id.c
index 2c6c698..1648f13 100644
--- a/board/gdsys/p1022/controlcenterd-id.c
+++ b/board/gdsys/p1022/controlcenterd-id.c
@@ -43,15 +43,6 @@
 #define CCDM_AUTO_FIRST_STAGE
 #endif
 
-/* enums from TCG specs */
-enum {
-	/* capability areas */
-	TPM_CAP_NV_INDEX	= 0x00000011,
-	TPM_CAP_HANDLE		= 0x00000014,
-	/* resource types */
-	TPM_RT_KEY	= 0x00000001,
-};
-
 /* CCDM specific contants */
 enum {
 	/* NV indices */
diff --git a/include/tpm.h b/include/tpm.h
index 9a6585d..800f29c 100644
--- a/include/tpm.h
+++ b/include/tpm.h
@@ -47,6 +47,42 @@ enum tpm_nv_index {
 	TPM_NV_INDEX_DIR	= 0x10000001,
 };
 
+enum tpm_resource_type {
+	TPM_RT_KEY	= 0x00000001,
+	TPM_RT_AUTH	= 0x00000002,
+	TPM_RT_HASH	= 0x00000003,
+	TPM_RT_TRANS	= 0x00000004,
+	TPM_RT_CONTEXT	= 0x00000005,
+	TPM_RT_COUNTER	= 0x00000006,
+	TPM_RT_DELEGATE	= 0x00000007,
+	TPM_RT_DAA_TPM	= 0x00000008,
+	TPM_RT_DAA_V0	= 0x00000009,
+	TPM_RT_DAA_V1	= 0x0000000A,
+};
+
+enum tpm_capability_areas {
+	TPM_CAP_ORD		= 0x00000001,
+	TPM_CAP_ALG		= 0x00000002,
+	TPM_CAP_PID		= 0x00000003,
+	TPM_CAP_FLAG		= 0x00000004,
+	TPM_CAP_PROPERTY	= 0x00000005,
+	TPM_CAP_VERSION		= 0x00000006,
+	TPM_CAP_KEY_HANDLE	= 0x00000007,
+	TPM_CAP_CHECK_LOADED	= 0x00000008,
+	TPM_CAP_SYM_MODE	= 0x00000009,
+	TPM_CAP_KEY_STATUS	= 0x0000000C,
+	TPM_CAP_NV_LIST		= 0x0000000D,
+	TPM_CAP_MFR		= 0x00000010,
+	TPM_CAP_NV_INDEX	= 0x00000011,
+	TPM_CAP_TRANS_ALG	= 0x00000012,
+	TPM_CAP_HANDLE		= 0x00000014,
+	TPM_CAP_TRANS_ES	= 0x00000015,
+	TPM_CAP_AUTH_ENCRYPT	= 0x00000017,
+	TPM_CAP_SELECT_SIZE	= 0x00000018,
+	TPM_CAP_DA_LOGIC	= 0x00000019,
+	TPM_CAP_VERSION_VAL	= 0x0000001A,
+};
+
 #define TPM_NV_PER_GLOBALLOCK		(1U << 15)
 #define TPM_NV_PER_PPWRITE		(1U << 0)
 #define TPM_NV_PER_READ_STCLEAR		(1U << 31)
@@ -594,4 +630,13 @@ uint32_t tpm_get_permanent_flags(struct tpm_permanent_flags *pflags);
  */
 uint32_t tpm_get_permissions(uint32_t index, uint32_t *perm);
 
+/**
+ * Flush a resource with a given handle and type from the TPM
+ *
+ * @param key_handle           handle of the resource
+ * @param resource_type                type of the resource
+ * @return return code of the operation
+ */
+uint32_t tpm_flush_specific(uint32_t key_handle, uint32_t resource_type);
+
 #endif /* __TPM_H */
diff --git a/lib/tpm.c b/lib/tpm.c
index 88f2406..98c20a0 100644
--- a/lib/tpm.c
+++ b/lib/tpm.c
@@ -645,6 +645,34 @@ uint32_t tpm_get_permissions(uint32_t index, uint32_t *perm)
 	return 0;
 }
 
+uint32_t tpm_flush_specific(uint32_t key_handle, uint32_t resource_type)
+{
+	const uint8_t command[18] = {
+		0x00, 0xc1,             /* TPM_TAG */
+		0x00, 0x00, 0x00, 0x12, /* parameter size */
+		0x00, 0x00, 0x00, 0xba, /* TPM_COMMAND_CODE */
+		0x00, 0x00, 0x00, 0x00, /* key handle */
+		0x00, 0x00, 0x00, 0x00, /* resource type */
+	};
+	const size_t key_handle_offset = 10;
+	const size_t resource_type_offset = 14;
+
+	uint8_t buf[COMMAND_BUFFER_SIZE], response[COMMAND_BUFFER_SIZE];
+	size_t response_length = sizeof(response);
+	uint32_t err;
+
+	if (pack_byte_string(buf, sizeof(buf), "sdd",
+			     0, command, sizeof(command),
+			     key_handle_offset, key_handle,
+			     resource_type_offset, resource_type))
+		return TPM_LIB_ERROR;
+
+	err = tpm_sendrecv_command(buf, response, &response_length);
+	if (err)
+		return err;
+	return 0;
+}
+
 #ifdef CONFIG_TPM_AUTH_SESSIONS
 
 /**
-- 
2.9.0