int X509_supported_extension(X509_EXTENSION *ex);
int X509_PURPOSE_set(int *p, int purpose);
int X509_check_issued(X509 *issuer, X509 *subject);
-int X509_check_akid(X509 *issuer, AUTHORITY_KEYID *akid);
+int X509_check_akid(const X509 *issuer, const AUTHORITY_KEYID *akid);
void X509_set_proxy_flag(X509 *x);
void X509_set_proxy_pathlen(X509 *x, long l);
long X509_get_proxy_pathlen(X509 *x);