+
+// Reject unknown/unconfigured protocols
+void protoreject(sessionidt s, tunnelidt t, uint8_t *p, uint16_t l, uint16_t proto)
+{
+
+ uint8_t buf[MAXETHER];
+ uint8_t *q;
+ int mru = session[s].mru;
+ if (mru < MINMTU) mru = MINMTU;
+ if (mru > sizeof(buf)) mru = sizeof(buf);
+
+ l += 6;
+ if (l > mru) l = mru;
+
+ q = makeppp(buf, sizeof(buf), 0, 0, s, t, PPPLCP);
+ if (!q) return;
+
+ *q = ProtocolRej;
+ *(q + 1) = ++sess_local[s].lcp_ident;
+ *(uint16_t *)(q + 2) = htons(l);
+ *(uint16_t *)(q + 4) = htons(proto);
+ memcpy(q + 6, p, l - 6);
+
+ if (proto == PPPIPV6CP)
+ LOG(3, s, t, "LCP: send ProtocolRej (IPV6CP: not configured)\n");
+ else
+ LOG(2, s, t, "LCP: sent ProtocolRej (0x%04X: unsupported)\n", proto);
+
+ tunnelsend(buf, l + (q - buf), t);
+}