TBB: Add an IO abstraction layer to load encrypted firmwares
TBBR spec advocates for optional encryption of firmwares (see optional
requirement: R060_TBBR_FUNCTION). So add an IO abstaction layer to
support firmware decryption that can be stacked above any underlying IO/
packaging layer like FIP etc. It aims to provide a framework to load any
encrypted IO payload.
Also, add plat_get_enc_key_info() to be implemented in a platform
specific manner as handling of encryption key may vary from one platform
to another.
Signed-off-by: Sumit Garg <sumit.garg@linaro.org>
Change-Id: I9892e0ddf00ebecb8981301dbfa41ea23e078b03
diff --git a/include/drivers/io/io_encrypted.h b/include/drivers/io/io_encrypted.h
new file mode 100644
index 0000000..9dcf061
--- /dev/null
+++ b/include/drivers/io/io_encrypted.h
@@ -0,0 +1,15 @@
+/*
+ * Copyright (c) 2020, Linaro Limited. All rights reserved.
+ * Author: Sumit Garg <sumit.garg@linaro.org>
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef IO_ENCRYPTED_H
+#define IO_ENCRYPTED_H
+
+struct io_dev_connector;
+
+int register_io_dev_enc(const struct io_dev_connector **dev_con);
+
+#endif /* IO_ENCRYPTED_H */
diff --git a/include/drivers/io/io_storage.h b/include/drivers/io/io_storage.h
index a301ad5..f2d641c 100644
--- a/include/drivers/io/io_storage.h
+++ b/include/drivers/io/io_storage.h
@@ -25,6 +25,7 @@
IO_TYPE_MTD,
IO_TYPE_MMC,
IO_TYPE_STM32IMAGE,
+ IO_TYPE_ENCRYPTED,
IO_TYPE_MAX
} io_type_t;
diff --git a/include/export/common/tbbr/tbbr_img_def_exp.h b/include/export/common/tbbr/tbbr_img_def_exp.h
index 3602554..89dbc58 100644
--- a/include/export/common/tbbr/tbbr_img_def_exp.h
+++ b/include/export/common/tbbr/tbbr_img_def_exp.h
@@ -85,12 +85,15 @@
/* Binary with STM32 header */
#define STM32_IMAGE_ID U(29)
+/* Encrypted image identifier */
+#define ENC_IMAGE_ID U(30)
+
/* Define size of the array */
#if defined(SPD_spmd)
#define MAX_SP_IDS U(8)
-#define MAX_NUMBER_IDS MAX_SP_IDS + U(30)
+#define MAX_NUMBER_IDS MAX_SP_IDS + U(31)
#else
-#define MAX_NUMBER_IDS U(30)
+#define MAX_NUMBER_IDS U(31)
#endif
#endif /* ARM_TRUSTED_FIRMWARE_EXPORT_COMMON_TBBR_TBBR_IMG_DEF_EXP_H */
diff --git a/include/plat/common/platform.h b/include/plat/common/platform.h
index 06b334d..5b5ebb9 100644
--- a/include/plat/common/platform.h
+++ b/include/plat/common/platform.h
@@ -27,6 +27,7 @@
struct mmap_region;
struct spm_mm_boot_info;
struct sp_res_desc;
+enum fw_enc_status_t;
/*******************************************************************************
* plat_get_rotpk_info() flags
@@ -274,6 +275,9 @@
int plat_set_nv_ctr2(void *cookie, const struct auth_img_desc_s *img_desc,
unsigned int nv_ctr);
int get_mbedtls_heap_helper(void **heap_addr, size_t *heap_size);
+int plat_get_enc_key_info(enum fw_enc_status_t fw_enc_status, uint8_t *key,
+ size_t *key_len, unsigned int *flags,
+ const uint8_t *img_id, size_t img_id_len);
/*******************************************************************************
* Secure Partitions functions
diff --git a/include/tools_share/firmware_encrypted.h b/include/tools_share/firmware_encrypted.h
new file mode 100644
index 0000000..7ca634f
--- /dev/null
+++ b/include/tools_share/firmware_encrypted.h
@@ -0,0 +1,42 @@
+/*
+ * Copyright (c) 2020, Linaro Limited. All rights reserved.
+ * Author: Sumit Garg <sumit.garg@linaro.org>
+ *
+ * SPDX-License-Identifier: BSD-3-Clause
+ */
+
+#ifndef FIRMWARE_ENCRYPTED_H
+#define FIRMWARE_ENCRYPTED_H
+
+#include <stdint.h>
+
+/* This is used as a signature to validate the encryption header */
+#define ENC_HEADER_MAGIC 0xAA640001U
+
+/* Firmware encryption status flag mask */
+#define FW_ENC_STATUS_FLAG_MASK 0x1
+
+/*
+ * SSK: Secret Symmetric Key
+ * BSSK: Binding Secret Symmetric Key
+ */
+enum fw_enc_status_t {
+ FW_ENC_WITH_SSK = 0,
+ FW_ENC_WITH_BSSK = 1,
+};
+
+#define ENC_MAX_IV_SIZE 16U
+#define ENC_MAX_TAG_SIZE 16U
+#define ENC_MAX_KEY_SIZE 32U
+
+struct fw_enc_hdr {
+ uint32_t magic;
+ uint16_t dec_algo;
+ uint16_t flags;
+ uint16_t iv_len;
+ uint16_t tag_len;
+ uint8_t iv[ENC_MAX_IV_SIZE];
+ uint8_t tag[ENC_MAX_TAG_SIZE];
+};
+
+#endif /* FIRMWARE_ENCRYPTED_H */