From 5a8fe1ee818e0f8a74fa088f6a3d705a01b6afbe Mon Sep 17 00:00:00 2001 From: Svyatoslav Ryhel Date: Tue, 14 Feb 2023 19:35:38 +0200 Subject: [PATCH] ARM: tegra20: implement BCT patching This function allows updating bootloader from u-boot on production devices without need in host PC. Be aware! It works only with re-crypt BCT. Tested-by: Robert Eckelmann # ASUS TF101 T20 Signed-off-by: Ramin Khonsari Signed-off-by: Svyatoslav Ryhel Signed-off-by: Tom --- arch/arm/mach-tegra/Kconfig | 2 +- arch/arm/mach-tegra/tegra20/Makefile | 5 +-- arch/arm/mach-tegra/tegra20/bct.c | 79 ++++++++++++++++++++++++++++++++++++ arch/arm/mach-tegra/tegra20/bct.h | 42 +++++++++++++++++++ doc/usage/cmd/ebtupdate.rst | 69 +++++++++++++++++++++++++++++++ 5 files changed, 193 insertions(+), 4 deletions(-) create mode 100644 arch/arm/mach-tegra/tegra20/bct.c create mode 100644 arch/arm/mach-tegra/tegra20/bct.h create mode 100644 doc/usage/cmd/ebtupdate.rst diff --git a/arch/arm/mach-tegra/Kconfig b/arch/arm/mach-tegra/Kconfig index 8490d42..464bd07 100644 --- a/arch/arm/mach-tegra/Kconfig +++ b/arch/arm/mach-tegra/Kconfig @@ -231,7 +231,7 @@ config CMD_ENTERRCM config CMD_EBTUPDATE bool "Enable 'ebtupdate' command" - depends on TEGRA30 + depends on TEGRA20 || TEGRA30 select TEGRA_CRYPTO help Updating u-boot from within u-boot in rather complex or even diff --git a/arch/arm/mach-tegra/tegra20/Makefile b/arch/arm/mach-tegra/tegra20/Makefile index 67454ff..991cabe 100644 --- a/arch/arm/mach-tegra/tegra20/Makefile +++ b/arch/arm/mach-tegra/tegra20/Makefile @@ -2,9 +2,8 @@ # # (C) Copyright 2010,2011 Nvidia Corporation. -ifdef CONFIG_SPL_BUILD -obj-y += cpu.o -endif +obj-$(CONFIG_SPL_BUILD) += cpu.o +obj-$(CONFIG_$(SPL_)CMD_EBTUPDATE) += bct.o # The AVP is ARMv4T architecture so we must use special compiler # flags for any startup files it might use. diff --git a/arch/arm/mach-tegra/tegra20/bct.c b/arch/arm/mach-tegra/tegra20/bct.c new file mode 100644 index 0000000..5eb4899 --- /dev/null +++ b/arch/arm/mach-tegra/tegra20/bct.c @@ -0,0 +1,79 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (c) 2022, Ramin + * Copyright (c) 2022, Svyatoslav Ryhel + */ + +#include +#include +#include +#include +#include "bct.h" +#include "uboot_aes.h" + +/* + * @param bct boot config table start in RAM + * @param ect bootloader start in RAM + * @param ebt_size bootloader file size in bytes + * Return: 0, or 1 if failed + */ +static int bct_patch(u8 *bct, u8 *ebt, u32 ebt_size) +{ + struct nvboot_config_table *bct_tbl = NULL; + u8 ebt_hash[AES128_KEY_LENGTH] = { 0 }; + u8 sbk[AES128_KEY_LENGTH] = { 0 }; + u8 *bct_hash = bct; + int ret; + + bct += BCT_HASH; + + memcpy(sbk, (u8 *)(bct + BCT_LENGTH), + NVBOOT_CMAC_AES_HASH_LENGTH * 4); + + ret = decrypt_data_block(bct, BCT_LENGTH, sbk); + if (ret) + return 1; + + ebt_size = roundup(ebt_size, EBT_ALIGNMENT); + + ret = encrypt_data_block(ebt, ebt_size, sbk); + if (ret) + return 1; + + ret = sign_enc_data_block(ebt, ebt_size, ebt_hash, sbk); + if (ret) + return 1; + + bct_tbl = (struct nvboot_config_table *)bct; + + memcpy((u8 *)&bct_tbl->bootloader[0].crypto_hash, + ebt_hash, NVBOOT_CMAC_AES_HASH_LENGTH * 4); + bct_tbl->bootloader[0].entry_point = CONFIG_SPL_TEXT_BASE; + bct_tbl->bootloader[0].load_addr = CONFIG_SPL_TEXT_BASE; + bct_tbl->bootloader[0].length = ebt_size; + + ret = encrypt_data_block(bct, BCT_LENGTH, sbk); + if (ret) + return 1; + + ret = sign_enc_data_block(bct, BCT_LENGTH, bct_hash, sbk); + if (ret) + return 1; + + return 0; +} + +static int do_ebtupdate(struct cmd_tbl *cmdtp, int flag, int argc, + char *const argv[]) +{ + u32 bct_addr = hextoul(argv[1], NULL); + u32 ebt_addr = hextoul(argv[2], NULL); + u32 ebt_size = hextoul(argv[3], NULL); + + return bct_patch((u8 *)bct_addr, (u8 *)ebt_addr, ebt_size); +} + +U_BOOT_CMD(ebtupdate, 4, 0, do_ebtupdate, + "update bootloader on re-crypted Tegra20 devices", + "" +); diff --git a/arch/arm/mach-tegra/tegra20/bct.h b/arch/arm/mach-tegra/tegra20/bct.h new file mode 100644 index 0000000..4b78aef --- /dev/null +++ b/arch/arm/mach-tegra/tegra20/bct.h @@ -0,0 +1,42 @@ +/* SPDX-License-Identifier: GPL-2.0+ */ + +#ifndef _BCT_H_ +#define _BCT_H_ + +/* + * Defines the BCT parametres for T20 + */ +#define BCT_LENGTH 0xFE0 +#define BCT_HASH 0x10 +#define EBT_ALIGNMENT 0x10 + +/* + * Defines the CMAC-AES-128 hash length in 32 bit words. (128 bits = 4 words) + */ +#define NVBOOT_CMAC_AES_HASH_LENGTH 4 + +/* + * Defines the maximum number of bootloader descriptions in the BCT. + */ +#define NVBOOT_MAX_BOOTLOADERS 4 + +struct nv_bootloader_info { + u32 version; + u32 start_blk; + u32 start_page; + u32 length; + u32 load_addr; + u32 entry_point; + u32 attribute; + u32 crypto_hash[NVBOOT_CMAC_AES_HASH_LENGTH]; +}; + +struct nvboot_config_table { + u32 unused0[4]; + u32 boot_data_version; + u32 unused1[668]; + struct nv_bootloader_info bootloader[NVBOOT_MAX_BOOTLOADERS]; + u32 unused2[508]; +}; + +#endif /* _BCT_H_ */ diff --git a/doc/usage/cmd/ebtupdate.rst b/doc/usage/cmd/ebtupdate.rst new file mode 100644 index 0000000..040cef3 --- /dev/null +++ b/doc/usage/cmd/ebtupdate.rst @@ -0,0 +1,69 @@ +.. SPDX-License-Identifier: GPL-2.0+: + +ebtupdate command +============= + +Synopsis +-------- + +:: + + ebtupdate [ [] []] + +Description +----------- + +The "ebtupdate" command is used to self-update bootloader on Tegra 2 and Tegra 3 +production devices which were processed using re-cryption. + +The "ebtupdate" performs encryption of new bootloader and decryption, patching +and re-encryption of BCT "in situ". After BCT and bootloader can be written in +their respective places. + +bct + address of BCT block pre-loaded into RAM. + +ebt + address of the bootloader pre-loaded into RAM. + +size + size of the pre-loaded bootloader. + +Example +------- + +This is the boot log of a LG Optimus Vu: + +:: + + => mmc dev 0 1 + switch to partitions #1, OK + mmc0(part 1) is current device + => mmc read $kernel_addr_r 0 $boot_block_size + MMC read: dev # 0, block # 0, count 4096 ... 4096 blocks read: OK + => load mmc 0:1 $ramdisk_addr_r $bootloader_file + 684783 bytes read in 44 ms (14.8 MiB/s) + => size mmc 0:1 $bootloader_file + => ebtupdate $kernel_addr_r $ramdisk_addr_r $filesize + => mmc dev 0 1 + switch to partitions #1, OK + mmc0(part 1) is current device + => mmc write $kernel_addr_r 0 $boot_block_size + MMC write: dev # 0, block # 0, count 4096 ... 4096 blocks written: OK + => mmc dev 0 2 + switch to partitions #2, OK + mmc0(part 2) is current device + => mmc write $ramdisk_addr_r 0 $boot_block_size + MMC write: dev # 0, block # 0, count 4096 ... 4096 blocks written: OK + +Configuration +------------- + +The ebtupdate command is only available if CONFIG_CMD_EBTUPDATE=y and +only on Tegra 2 and Tegra 3 configurations. + +Return value +------------ + +The return value $? is set to 0 (true) if everything went successfully. If an +error occurs, the return value $? is set to 1 (false). -- 2.7.4