CBS_get_u24
int CBS_get_u24(CBS *cbs, uint32_t *out);
int CBS_get_u24(CBS *cbs, uint32_t *out);
if (!CBS_get_u24(header, &msg_len))
if (!CBS_get_u24(header, &frag_off))
if (!CBS_get_u24(header, &frag_len))
!CBS_get_u24(&cbs, &l)) {
if (!CBS_get_u24(&cbs, &hs_msg_length))
if (!CBS_get_u24(&cbs, &msg_len))
CHECK(CBS_get_u24(&prefixed, &u32));
CHECK(CBS_get_u24(&data, &u32));