[U-Boot] [PATCH v2 1/1] avb: add support for named persistent values
Igor Opaniuk
igor.opaniuk at linaro.org
Fri Dec 14 17:45:03 UTC 2018
AVB version 1.1 introduces support for named persistent values
that must be tamper evident and allows AVB to store arbitrary key-value
pairs [1].
Introduce implementation of two additional AVB operations
read_persistent_value()/write_persistent_value() for retrieving/storing
named persistent values.
Correspondent pull request in the OP-TEE OS project repo [2].
[1]: https://android.googlesource.com/platform/external/avb/+/android-9.0.0_r22
[2]: https://github.com/OP-TEE/optee_os/pull/2699
Signed-off-by: Igor Opaniuk <igor.opaniuk at linaro.org>
---
Changes in v2:
- fix output format for avb read_pvalue/write_pvalue commands
- fix issue with named value buffer size
cmd/avb.c | 78 +++++++++++++++++++++++++++++
common/avb_verify.c | 122 +++++++++++++++++++++++++++++++++++++++++++++
include/tee.h | 2 +
include/tee/optee_ta_avb.h | 16 ++++++
4 files changed, 218 insertions(+)
diff --git a/cmd/avb.c b/cmd/avb.c
index ff00be4..8387cc7 100644
--- a/cmd/avb.c
+++ b/cmd/avb.c
@@ -340,6 +340,76 @@ int do_avb_is_unlocked(cmd_tbl_t *cmdtp, int flag,
return CMD_RET_FAILURE;
}
+int do_avb_read_pvalue(cmd_tbl_t *cmdtp, int flag, int argc,
+ char * const argv[])
+{
+ const char *name;
+ size_t bytes;
+ size_t bytes_read;
+ void *buffer;
+
+ if (!avb_ops) {
+ printf("AVB 2.0 is not initialized, run 'avb init' first\n");
+ return CMD_RET_FAILURE;
+ }
+
+ if (argc != 3)
+ return CMD_RET_USAGE;
+
+ name = argv[1];
+ bytes = simple_strtoul(argv[2], NULL, 10);
+ buffer = malloc(bytes);
+ if (!buffer)
+ return CMD_RET_FAILURE;
+
+ printf("Reading persistent value, name = %s, bytes = %ld\n",
+ name, bytes);
+ if (avb_ops->read_persistent_value(avb_ops, name, bytes, buffer,
+ &bytes_read) == AVB_IO_RESULT_OK) {
+ printf("Read %ld bytes, value = %s\n", bytes_read,
+ (char *)buffer);
+ free(buffer);
+ return CMD_RET_SUCCESS;
+ }
+
+ printf("Failed to write in partition\n");
+
+ free(buffer);
+
+ return CMD_RET_FAILURE;
+}
+
+int do_avb_write_pvalue(cmd_tbl_t *cmdtp, int flag, int argc,
+ char * const argv[])
+{
+ const char *name;
+ const char *value;
+
+ if (!avb_ops) {
+ printf("AVB 2.0 is not initialized, run 'avb init' first\n");
+ return CMD_RET_FAILURE;
+ }
+
+ if (argc != 3)
+ return CMD_RET_USAGE;
+
+ name = argv[1];
+ value = argv[2];
+
+ printf("Writing persistent value, name = %s, value = %s\n",
+ name, value);
+ if (avb_ops->write_persistent_value(avb_ops, name, strlen(value) + 1,
+ (const uint8_t *)value) ==
+ AVB_IO_RESULT_OK) {
+ printf("Wrote %ld bytes\n", strlen(value) + 1);
+ return CMD_RET_SUCCESS;
+ }
+
+ printf("Failed to write persistent value\n");
+
+ return CMD_RET_FAILURE;
+}
+
static cmd_tbl_t cmd_avb[] = {
U_BOOT_CMD_MKENT(init, 2, 0, do_avb_init, "", ""),
U_BOOT_CMD_MKENT(read_rb, 2, 0, do_avb_read_rb, "", ""),
@@ -350,6 +420,10 @@ static cmd_tbl_t cmd_avb[] = {
U_BOOT_CMD_MKENT(read_part_hex, 4, 0, do_avb_read_part_hex, "", ""),
U_BOOT_CMD_MKENT(write_part, 5, 0, do_avb_write_part, "", ""),
U_BOOT_CMD_MKENT(verify, 1, 0, do_avb_verify_part, "", ""),
+#ifdef CONFIG_OPTEE_TA_AVB
+ U_BOOT_CMD_MKENT(read_pvalue, 3, 0, do_avb_read_pvalue, "", ""),
+ U_BOOT_CMD_MKENT(write_pvalue, 3, 0, do_avb_write_pvalue, "", ""),
+#endif
};
static int do_avb(cmd_tbl_t *cmdtp, int flag, int argc, char * const argv[])
@@ -384,6 +458,10 @@ U_BOOT_CMD(
" partition <partname> and print to stdout\n"
"avb write_part <partname> <offset> <num> <addr> - write <num> bytes to\n"
" <partname> by <offset> using data from <addr>\n"
+#ifdef CONFIG_OPTEE_TA_AVB
+ "avb read_pvalue <name> <bytes> - read a persistent value <name>\n"
+ "avb write_pvalue <name> <value> - write a persistent value <name>\n"
+#endif
"avb verify - run verification process using hash data\n"
" from vbmeta structure\n"
);
diff --git a/common/avb_verify.c b/common/avb_verify.c
index a8c5a3e..292ad8f 100644
--- a/common/avb_verify.c
+++ b/common/avb_verify.c
@@ -647,6 +647,10 @@ static AvbIOResult invoke_func(struct AvbOpsData *ops_data, u32 func,
return AVB_IO_RESULT_OK;
case TEE_ERROR_OUT_OF_MEMORY:
return AVB_IO_RESULT_ERROR_OOM;
+ case TEE_ERROR_STORAGE_NO_SPACE:
+ return AVB_IO_RESULT_ERROR_INSUFFICIENT_SPACE;
+ case TEE_ERROR_ITEM_NOT_FOUND:
+ return AVB_IO_RESULT_ERROR_NO_SUCH_VALUE;
case TEE_ERROR_TARGET_DEAD:
/*
* The TA has paniced, close the session to reload the TA
@@ -847,6 +851,120 @@ static AvbIOResult get_size_of_partition(AvbOps *ops,
return AVB_IO_RESULT_OK;
}
+static AvbIOResult read_persistent_value(AvbOps *ops,
+ const char *name,
+ size_t buffer_size,
+ u8 *out_buffer,
+ size_t *out_num_bytes_read)
+{
+ AvbIOResult rc;
+ struct tee_shm *shm_name;
+ struct tee_shm *shm_buf;
+ struct tee_param param[2];
+ struct udevice *tee;
+
+ if (get_open_session(ops->user_data))
+ return AVB_IO_RESULT_ERROR_IO;
+
+ tee = ((struct AvbOpsData *)ops->user_data)->tee;
+
+ rc = tee_shm_alloc(tee, strlen(name) + 1,
+ TEE_SHM_ALLOC, &shm_name);
+ if (rc)
+ return AVB_IO_RESULT_ERROR_OOM;
+
+ rc = tee_shm_alloc(tee, buffer_size,
+ TEE_SHM_ALLOC, &shm_buf);
+ if (rc) {
+ rc = AVB_IO_RESULT_ERROR_OOM;
+ goto free_name;
+ }
+
+ memcpy(shm_name->addr, name, strlen(name) + 1);
+
+ memset(param, 0, sizeof(param));
+ param[0].attr = TEE_PARAM_ATTR_TYPE_MEMREF_INPUT;
+ param[0].u.memref.shm = shm_name;
+ param[0].u.memref.size = strlen(name) + 1;
+ param[1].attr = TEE_PARAM_ATTR_TYPE_MEMREF_INOUT;
+ param[1].u.memref.shm = shm_buf;
+ param[1].u.memref.size = buffer_size;
+
+ rc = invoke_func(ops->user_data, TA_AVB_CMD_READ_PERSIST_VALUE,
+ 2, param);
+ if (rc)
+ goto out;
+
+ *out_num_bytes_read = param[1].u.memref.size;
+
+ memcpy(out_buffer, shm_buf->addr, *out_num_bytes_read);
+
+ return AVB_IO_RESULT_OK;
+
+out:
+ tee_shm_free(shm_buf);
+free_name:
+ tee_shm_free(shm_name);
+
+ return rc;
+}
+
+static AvbIOResult write_persistent_value(AvbOps *ops,
+ const char *name,
+ size_t value_size,
+ const u8 *value)
+{
+ AvbIOResult rc;
+ struct tee_shm *shm_name;
+ struct tee_shm *shm_buf;
+ struct tee_param param[2];
+ struct udevice *tee;
+
+ if (get_open_session(ops->user_data))
+ return AVB_IO_RESULT_ERROR_IO;
+
+ tee = ((struct AvbOpsData *)ops->user_data)->tee;
+
+ if (!value_size)
+ return AVB_IO_RESULT_ERROR_NO_SUCH_VALUE;
+
+ rc = tee_shm_alloc(tee, strlen(name) + 1,
+ TEE_SHM_ALLOC, &shm_name);
+ if (rc)
+ return AVB_IO_RESULT_ERROR_OOM;
+
+ rc = tee_shm_alloc(tee, value_size,
+ TEE_SHM_ALLOC, &shm_buf);
+ if (rc) {
+ rc = AVB_IO_RESULT_ERROR_OOM;
+ goto free_name;
+ }
+
+ memcpy(shm_name->addr, name, strlen(name) + 1);
+ memcpy(shm_buf->addr, value, value_size);
+
+ memset(param, 0, sizeof(param));
+ param[0].attr = TEE_PARAM_ATTR_TYPE_MEMREF_INPUT;
+ param[0].u.memref.shm = shm_name;
+ param[0].u.memref.size = strlen(name) + 1;
+ param[1].attr = TEE_PARAM_ATTR_TYPE_MEMREF_INPUT;
+ param[1].u.memref.shm = shm_buf;
+ param[1].u.memref.size = value_size;
+
+ rc = invoke_func(ops->user_data, TA_AVB_CMD_WRITE_PERSIST_VALUE,
+ 2, param);
+ if (rc)
+ goto out;
+
+ return AVB_IO_RESULT_OK;
+
+out:
+ tee_shm_free(shm_buf);
+free_name:
+ tee_shm_free(shm_name);
+
+ return rc;
+}
/**
* ============================================================================
* AVB2.0 AvbOps alloc/initialisation/free
@@ -870,6 +988,10 @@ AvbOps *avb_ops_alloc(int boot_device)
ops_data->ops.read_is_device_unlocked = read_is_device_unlocked;
ops_data->ops.get_unique_guid_for_partition =
get_unique_guid_for_partition;
+#ifdef CONFIG_OPTEE_TA_AVB
+ ops_data->ops.write_persistent_value = write_persistent_value;
+ ops_data->ops.read_persistent_value = read_persistent_value;
+#endif
ops_data->ops.get_size_of_partition = get_size_of_partition;
ops_data->mmc_dev = boot_device;
diff --git a/include/tee.h b/include/tee.h
index 98b1c9c..69de924 100644
--- a/include/tee.h
+++ b/include/tee.h
@@ -42,7 +42,9 @@
#define TEE_ERROR_COMMUNICATION 0xffff000e
#define TEE_ERROR_SECURITY 0xffff000f
#define TEE_ERROR_OUT_OF_MEMORY 0xffff000c
+#define TEE_ERROR_OVERFLOW 0xffff300f
#define TEE_ERROR_TARGET_DEAD 0xffff3024
+#define TEE_ERROR_STORAGE_NO_SPACE 0xffff3041
#define TEE_ORIGIN_COMMS 0x00000002
#define TEE_ORIGIN_TEE 0x00000003
diff --git a/include/tee/optee_ta_avb.h b/include/tee/optee_ta_avb.h
index 074386a..ef84488 100644
--- a/include/tee/optee_ta_avb.h
+++ b/include/tee/optee_ta_avb.h
@@ -45,4 +45,20 @@
*/
#define TA_AVB_CMD_WRITE_LOCK_STATE 3
+/*
+ * Reads a persistent value corresponding to the given name.
+ *
+ * in params[0].u.memref: persistent value name
+ * ioout params[1].u.memref: read persistent value buffer
+ */
+#define TA_AVB_CMD_READ_PERSIST_VALUE 4
+
+/*
+ * Writes a persistent value corresponding to the given name.
+ *
+ * in params[0].u.memref: persistent value name
+ * in params[1].u.memref: persistent value buffer to write
+ */
+#define TA_AVB_CMD_WRITE_PERSIST_VALUE 5
+
#endif /* __TA_AVB_H */
--
2.7.4
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