SADB_X_EALG_NULL_AES_GMAC
bool aes_gmac = (alg == SADB_X_EALG_NULL_AES_GMAC);
case SADB_X_EALG_NULL_AES_GMAC:
.sadb_alg_id = SADB_X_EALG_NULL_AES_GMAC,