something wrong with Functions based on SM2

[DaiJiaKang]

i want to use SM2 API.
first, i create IppsGFpState with ippsGFpMethod_p256sm2 & bignum P, and then i know the A, B, X, Y, N of the ECC
second, i create IppsGFpECState and figure out the publicKey & privatekey
third, i want to create IppsECES_StateSM2. At the same time, something wrong, i always get the ippStsNotSupportedModeErr err when calling the IppStatus ippsGFpECESGetSize_SM2(const IppsGFpECState* pEC, int* pSize);
this is my ECC parameter:
Ipp8u P_str[] = "\xFF\xFF\xFF\xFE\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\x00\x00\x00\x00\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF";
Ipp8u A_str[] = "\xFF\xFF\xFF\xFE\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\x00\x00\x00\x00\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFC";
Ipp8u B_str[] = "\x28\xE9\xFA\x9E\x9D\x9F\x5E\x34\x4D\x5A\x9E\x4B\xCF\x65\x09\xA7\xF3\x97\x89\xF5\x15\xAB\x8F\x92\xDD\xBC\xBD\x41\x4D\x94\x0E\x93";
Ipp8u X_str[] = "\x32\xC4\xAE\x2C\x1F\x19\x81\x19\x5F\x99\x04\x46\x6A\x39\xC9\x94\x8F\xE3\x0B\xBF\xF2\x66\x0B\xE1\x71\x5A\x45\x89\x33\x4C\x74\xC7";
Ipp8u Y_str[] = "\xBC\x37\x36\xA2\xF4\xF6\x77\x9C\x59\xBD\xCE\xE3\x6B\x69\x21\x53\xD0\xA9\x87\x7C\xC6\x2A\x47\x40\x02\xDF\x32\xE5\x21\x39\xF0\xA0";
Ipp8u N_str[] = "\xFF\xFF\xFF\xFE\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\xFF\x72\x03\xDF\x6B\x21\xC6\x05\x2B\x53\xBB\xF4\x09\x39\xD5\x41\x23";
help me pls!

[skirillo]

It seems the only situation where ippsGFpECESGetSize_SM2() returns the ippStsNotSupportedModeErr status is incorrect initialization of the Elliptic Curve (or underlying finite field). If you send a short example illustrating this problem, it helps to understand the source of issue and fix it.
By the way, the SM2 curve has fixed P, A, B, X, Y and N parameters, Are you sure your values (above) are corresponds to SM2 EC?

[DaiJiaKang]

@skirillo

example.zip

[skirillo]

In your example I did not find the following:
'ipp_print_BN' undefined; assuming extern returning int
'ipp_getBN_pint' undefined; assuming extern returning int
'get_time_seed' undefined; assuming extern returning int
'ipp_ramdom_init' undefined; assuming extern returning int
'ipp_random_BN_get' undefined; assuming extern returning int
'ipp_mod_BN' undefined; assuming extern returning int
'ipp_delete_BN' undefined; assuming extern returning int
'ipp_random_release' undefined; assuming extern returning int
Could you prepare compete example?

[DaiJiaKang]

example.zip
@skirillo

[skirillo]

You sample is not complete. Undefined ipp_extget_BN function.

[skirillo]

when EC created the underlying field is not copied into EC state but instead saved the pointer to GF state only.
In the ipp_ecc_ende_sm2Gen() GF state created correctly but DESTROYED before return.
The ipp_ecc_ende_sm2init() require correct content of EC state including reference to GF state. But it destroyed ..
It's the reason why ippsGFpECESGetSize_SM2() returns error status.

I recommend to take a look at SM2 encryption/decryption protocol

[DaiJiaKang]

i get it,thank u very much!