+ int proto, i;
+ struct protent *protp;
+
+ if (len < PPP_HDRLEN)
+ return 0;
+ proto = PPP_PROTOCOL(p);
+#ifdef PPP_FILTER
+ if (active_filter.bf_len != 0
+ && bpf_filter(active_filter.bf_insns, frame, len, len) == 0)
+ return 0;
+#endif
+ for (i = 0; (protp = protocols[i]) != NULL; ++i) {
+ if (protp->protocol < 0xC000 && (protp->protocol & ~0x8000) == proto) {
+ if (!protp->enabled_flag)
+ return 0;
+ if (protp->active_pkt == NULL)
+ return 1;
+ return (*protp->active_pkt)(p, len);
+ }
+ }
+ return 0; /* not a supported protocol !!?? */