Post #1530953

oh this is interesting a while ago ransomhouse leaked data from some chinese microcontroller company, and it seems nobody really noticed this company also makes TPMs a lot of the data looks crypted, but there’s some plaintext in there including listing files (which for C code seems to be preprocessor debug-output, with single character prefix denoting what the preprocessor did, comments and preprocessor directives and preprocessor output are ALL included) for the firmware of a production TPM implementation the anti-glitch stuff in particular seems like the usual fare for such, but if you haven’t seen such before then it looks kind of weird: enum { Cpy_OK = 0x55a55aa5, SetData_OK = 0x7CCF62F2, XOR_OK = 0x6A17D34A, RandomSort_OK = 0x51261DC5, CheckOrder_OK = 0x54830C23, Reverse_OK = 0x43C94C71, IsZero_YES = 0x7a7a7a7a, IsZero_NOT = 0x07070707, IsOne_YES = 0x6a6a6a6a, IsOne_NOT = 0x06060606, Cmp_EQUAL = 0x4a4a4a4a, Cmp_LESS = (int32_t)0x95959595, Cmp_GREATER = 0x6c6c6c6c, Cmp_ERROR = 0x00044400, SetData_ERROR = 0x00055500, CheckOrder_ERROR = 0x00066600, IsZero_ERROR = 0x00077700, Cpy_ERROR = 0x00088800, Reverse_ERROR = 0x00099900, XOR_ERROR = 0x000aaa00, RandomSort_ERROR = 0x000bbb00, }; ​#define TPM_ATTACK() \ { \ tpm_set_shutdown_mode(); \ return TPM_RC_FAILURE; \ } ​#define xor_sum3(a, b, c) ((UINT32)(a) ^ (UINT32)(b) ^ (UINT32)(c)) before preprocessor: // Load the persistent data UINT32 infoAddr = 0; ret = Cpy_U32_sum((UINT32*)&go, (UINT32*)NV_GO_START, sizeof(go) >> 2, xor_sum3(&go, NV_GO_START, sizeof(go) >> 2)); if (ret != Cpy_OK) { TPM_ATTACK(); } after preprocessor: // Load the persistent data UINT32 infoAddr = 0; ret = Cpy_U32_sum((UINT32*)&go, (UINT32*)((((0x6C800 + ((0x5) << 9)) + ((0x2) << 9)) + (0x00000200)) + (0x00000200)), sizeof(go) >> 2, ((UINT32)(&go) ^ (UINT32)(((((0x6C800 + ((0x5) << 9)) + ((0x2) << 9)) + (0x00000200)) + (0x00000200))) ^ (UINT32)(sizeof(go) >> 2))); if (ret != Cpy_OK) { { tpm_set_shutdown_mode(); return (TPM_RC)((TPM_RC)(0x100)+0x001); }; }