Hello, I am very sorry about last email by mistakes. I have some questions about multiplication on ecp curves. I add an ecp curve parameter in ecp_curve.c form SM2 algorithm standard, and the parameter is as follow:

Then I followed the loading method of secp256r1 to load, but I don’t know how to perform fast calculations, so I commented NIST_MODP( p256 ).

#if defined(MBEDTLS_ECP_DP_SECP256R1_ENABLED) caseMBEDTLS_ECP_DP_SECP256R1: NIST_MODP( p256 ); return( LOAD_GROUP( secp256r1 ) ); #endif

#if defined(MBEDTLS_ECP_DP_SM256_ENABLED) caseMBEDTLS_ECP_DP_SM256: //NIST_MODP( p256 ); return( LOAD_GROUP_A( sm256 ) ); #endif

Then I call the functional interface mbedtls_ecp_mul to perform the multiplication operation, but the heap memory keeps increasing .

voidtest() { intret; mbedtls_mpiUd; mbedtls_ecp_groupgrp; mbedtls_ecp_pointT_Q;

mbedtls_mpi_init(&Ud); mbedtls_ecp_group_init( &grp ); mbedtls_ecp_point_init( &T_Q );

ret=mbedtls_mpi_read_binary(&Ud, arrUd, sizeof(arr_U_d)); // ret = mbedtls_ecp_group_load(&grp,MBEDTLS_ECP_DP_SECP256R1); ret=mbedtls_ecp_group_load(&grp,MBEDTLS_ECP_DP_SM256); ret=mbedtls_ecp_mul(&grp, &T_Q, &Ud, &(grp.G), NULL, NULL) ; printf("%x\n", -ret);

mbedtls_mpi_free(&Ud); mbedtls_ecp_group_free( &grp ); mbedtls_ecp_point_free( &T_Q ); } intmain()

{ for(inti=0; i<10; i++) test(); return0; }

The heap memory is mesaured by massif( valgring tools),

Can someone tell me what this is because of and how to fix this problem ?

Best Regards.

Shudong Zhang