i2d_ASN1_OCTET_STRING
LCRYPTO_ALIAS(i2d_ASN1_OCTET_STRING);
int i2d_ASN1_OCTET_STRING(ASN1_OCTET_STRING *a, unsigned char **out);
len = i2d_ASN1_OCTET_STRING(&oct, out);
if ((der_len = i2d_ASN1_OCTET_STRING(aos, &der)) < 0)
LCRYPTO_USED(i2d_ASN1_OCTET_STRING);
i = i2d_ASN1_OCTET_STRING(&sig, NULL);
i2d_ASN1_OCTET_STRING(&sig, &p);