STM32 header for binary files

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Wiki（讨论 | 贡献）2020年11月2日 (一) 09:16的版本

STM32标头是STMicroelectronics标头，是由 ROM code 和 TF-A加载的二进制文件所需要的。

Description

STM32 header.png

由ROM code 和 TF-A 加载的每个二进制映像（已签名或未签名）都需要在二进制数据的顶部添加特定的STM32标头，标题包括认证信息。

Name Length Byte Offset Description
Magic number 32 bits 0 4 bytes in big endian:
'S', 'T', 'M', 0x32 = 0x53544D32
Image signature 512 bits 4 ECDSA signature for image authentication[Note 1]
Image checksum 32 bits 68 Checksum of the payload[Note 2]
Header version 32 bits 72 Header version v1.0 = 0x00010000
Byte0: reserved
Byte1:major version = 0x01
Byte2: minor version = 0x00
Byte3: reserved
Image length 32 bits 76 Length of image in bytes[Note 3]
Image entry Point 32 bits 80 Entry point of image
Reserved1 32 bits 84 Reserved
Load address 32 bits 88 Load address of image[Note 4]
Reserved2 32 bits 92 Reserved
Version number 32 bits 96 Image Version (monotonic number)[Note 5]
Option flags 32 bits 100 b0=1: no signature verification[Note 6]
ECDSA algorithm 32 bits 104 1: P-256 NIST ; 2: brainpool 256
ECDSA public key 512 bits 108 ECDSA public key to be used to verify the signature.[Note 7]
Padding 83 Bytes 172 Reserved padding bytes[Note 8]. Must all be set to 0
Binary type 1 Byte 255 Used to check the binary type
0x00: U-Boot
0x10-0x1F: TF-A
0x20-0X2F: OPTEE
0x30: Copro
  1. ↑ Signature is calculated from first byte of header version field to last byte of image given by image length field.
  2. ↑ 32-bit sum of all payload bytes accessed as 8-bit unsigned numbers, discarding any overflow bits. Used to check the downloaded image integrity when signature is not used (if b0=1 in Option flags).
  3. ↑ Length is the length of the built image, it does not include the length of the STM32 header.
  4. ↑ This field is not used by ROM code.
  5. ↑ Image version number is an anti rollback monotonic counter. The ROM code checks that it is higher or equal to the monotonic counter stored in OTP.
  6. ↑ Enabling signature verification is mandatory on secure closed chips.
  7. ↑ This field is an extract of PEM public key file that only kept the ECC Point coordinates x and y in a raw binary format (RFC 5480). This field will be hashed with SHA-256 and compared to the Hash of pubKey that is stored in OTP.
  8. ↑ This padding forces STM32 header size to 256 bytes (0x100).


用于 Version number 和 Hash of pubKey 的动态口令在 “OTP 配置”一章中定义 ROM code overview.

取自“http://wiki.100ask.org/index.php?title=STM32_header_for_binary_files&oldid=7229”