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The S-expression based interface is not optimal for certain operations on elliptic curves. Thus a few special functions are implemented to support common operations on curves with one of these assigned curve ids:

`GCRY_ECC_CURVE25519`

`GCRY_ECC_CURVE448`

- Function:
*unsigned int***gcry_ecc_get_algo_keylen***(int*`curveid`); -
Returns the length in bytes of a point on the curve with the id

`curveid`. 0 is returned for curves which have no assigned id.

- Function:
*gpg_error_t***gcry_ecc_mul_point***(int*`curveid`, unsigned char *`result`, const unsigned char *`scalar`, const unsigned char *`point`) -
This function computes the scalar multiplication on the Montgomery form of the curve with id

`curveid`. If`point`is`NULL`

, the base point of the curve is used. The caller needs to provide a large enough buffer for`result`and a valid`scalar`and`point`.