+ mp->b_band = 0;
+#ifdef PRIOQ
+ /* Extract s_port & d_port from IP-packet, the code is a bit
+ dirty here, but so am I, too... */
+ if (mp->b_datap->db_type == M_PROTO && us->sap == PPP_IP
+ && mp->b_cont != 0) {
+ u_char *bb, *tlh;
+ int iphlen, len;
+ u_short *ptr;
+ u_char band_unset, cur_band, syn;
+ u_short s_port, d_port;
+
+ bb = mp->b_cont->b_rptr; /* bb points to IP-header*/
+ len = mp->b_cont->b_wptr - mp->b_cont->b_rptr;
+ syn = 0;
+ s_port = IPPORT_DEFAULT;
+ d_port = IPPORT_DEFAULT;
+ if (len >= 20) { /* 20 = minimum length of IP header */
+ iphlen = (bb[0] & 0x0f) * 4;
+ tlh = bb + iphlen;
+ len -= iphlen;
+ switch (bb[9]) {
+ case IPPROTO_TCP:
+ if (len >= 20) { /* min length of TCP header */
+ s_port = (tlh[0] << 8) + tlh[1];
+ d_port = (tlh[2] << 8) + tlh[3];
+ syn = tlh[13] & 0x02;
+ }
+ break;
+ case IPPROTO_UDP:
+ if (len >= 8) { /* min length of UDP header */
+ s_port = (tlh[0] << 8) + tlh[1];
+ d_port = (tlh[2] << 8) + tlh[3];
+ }
+ break;
+ }
+ }
+
+ /*
+ * Now calculate b_band for this packet from the
+ * port-priority table.
+ */
+ ptr = prioq_table;
+ cur_band = max_band;
+ band_unset = 1;
+ while (*ptr) {
+ while (*ptr && band_unset)
+ if (s_port == *ptr || d_port == *ptr++) {
+ mp->b_band = cur_band;
+ band_unset = 0;
+ break;
+ }
+ ptr++;
+ cur_band--;
+ }
+ if (band_unset)
+ mp->b_band = def_band;
+ /* It may be usable to urge SYN packets a bit */
+ if (syn)
+ mp->b_band++;
+ }
+#endif /* PRIOQ */