#Checksum reverse engineer

1 messages · Page 1 of 1 (latest)

harsh rapids
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I had a problem and came here hoping someone could help me. Below are the values taken from 4 different EEPROM offset 0100 addresses (little Endian). The payload (data) from address 0100-0105. The checksum (4 Bytes) from address 0108-010B. The formula for the checksum is not clear to me. Those who can help me with this
5F 67 06 00 C5 26 00 00 93 AF D5 C5 00 00 00 00
AB 67 06 00 C5 26 00 00 D5 24 E6 92 00 00 00 00
DD DE 09 00 C5 26 00 00 86 4E BB D2 00 00 00 00
A1 2D 06 00 C5 26 00 00 E2 6E 94 7F 00 00 00 00

frigid topaz
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Given that it's from a firmware and 4 byte long, I'd probably expect it to be CRC32

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Try to search through the binary for some known CRC32 polynomials. The constants option in the find view can do that

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But of course, they could have used a custom polynomial as well or it might not be CRC32. In that case you don't have much choice but to properly reverse engineer the firmware