OK, here it is - irdp support. But don't expect me to fix any bugs in it.
diff --git a/zebra/irdp_main.c b/zebra/irdp_main.c
new file mode 100644
index 0000000..dac6aea
--- /dev/null
+++ b/zebra/irdp_main.c
@@ -0,0 +1,347 @@
+/*
+ *
+ * Copyright (C) 2000 Robert Olsson.
+ * Swedish University of Agricultural Sciences
+ *
+ * This file is part of GNU Zebra.
+ *
+ * GNU Zebra is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the
+ * Free Software Foundation; either version 2, or (at your option) any
+ * later version.
+ *
+ * GNU Zebra is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with GNU Zebra; see the file COPYING. If not, write to the Free
+ * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA
+ * 02111-1307, USA.
+ */
+
+/*
+ * This work includes work with the following copywrite:
+ *
+ * Copyright (C) 1997, 2000 Kunihiro Ishiguro
+ *
+ */
+
+/*
+ * Thanks to Jens Låås at Swedish University of Agricultural Sciences
+ * for reviewing and tests.
+ */
+
+
+#include <zebra.h>
+
+#ifdef HAVE_IRDP
+
+#include "if.h"
+#include "vty.h"
+#include "sockunion.h"
+#include "prefix.h"
+#include "command.h"
+#include "memory.h"
+#include "stream.h"
+#include "ioctl.h"
+#include "connected.h"
+#include "log.h"
+#include "zclient.h"
+#include "thread.h"
+#include "zebra/interface.h"
+#include "zebra/rtadv.h"
+#include "zebra/rib.h"
+#include "zebra/zserv.h"
+#include "zebra/redistribute.h"
+#include "zebra/irdp.h"
+#include <netinet/ip_icmp.h>
+
+#include "if.h"
+#include "sockunion.h"
+#include "log.h"
+
+/* GLOBAL VARS */
+
+/* Master of threads. */
+extern struct zebra_t zebrad;
+struct thread *t_irdp_raw;
+
+/* Timer interval of irdp. */
+int irdp_timer_interval = IRDP_DEFAULT_INTERVAL;
+
+int irdp_read_raw(struct thread *r);
+int in_cksum (void *ptr, int nbytes);
+extern int irdp_sock;
+void send_packet(struct interface *ifp,
+ struct stream *s,
+ u_int32_t dst,
+ struct prefix *p,
+ u_int32_t ttl);
+
+void irdp_if_init ();
+
+char *
+inet_2a(u_int32_t a, char *b)
+{
+ sprintf(b, "%u.%u.%u.%u",
+ (a ) & 0xFF,
+ (a>> 8) & 0xFF,
+ (a>>16) & 0xFF,
+ (a>>24) & 0xFF);
+ return b;
+}
+
+int
+irdp_sock_init (void)
+{
+ int ret, i;
+
+ irdp_sock = socket (AF_INET, SOCK_RAW, IPPROTO_ICMP);
+ if (irdp_sock < 0) {
+ zlog_warn ("IRDP: can't create irdp socket %s", strerror(errno));
+ return irdp_sock;
+ };
+
+ i = 1;
+ ret = setsockopt (irdp_sock, IPPROTO_IP, IP_TTL,
+ (void *) &i, sizeof (i));
+ if (ret < 0) {
+ zlog_warn ("IRDP: can't do irdp sockopt %s", strerror(errno));
+ return ret;
+ };
+
+ i = 1;
+ ret = setsockopt (irdp_sock, IPPROTO_IP, IP_PKTINFO,
+ (void *) &i, sizeof (i));
+ if (ret < 0) {
+ zlog_warn ("IRDP: can't do irdp sockopt %s", strerror(errno));
+ return ret;
+ };
+
+ t_irdp_raw = thread_add_read (zebrad.master, irdp_read_raw, NULL, irdp_sock);
+
+ return irdp_sock;
+}
+
+
+int get_pref(struct irdp_interface *irdp, struct prefix *p)
+{
+ listnode node;
+ struct Adv *adv;
+
+ /* Use default preference or use the override pref */
+
+ if( irdp->AdvPrefList == NULL ) return irdp->Preference;
+
+ for (node = listhead (irdp->AdvPrefList); node; nextnode (node)) {
+ adv = getdata (node);
+ if( p->u.prefix4.s_addr == adv->ip.s_addr )
+ return adv->pref;
+ }
+ return irdp->Preference;
+}
+
+/* Make ICMP Router Advertisement Message. */
+int make_advertisement_packet (struct interface *ifp,
+ struct prefix *p,
+ struct stream *s)
+{
+ struct zebra_if *zi=ifp->info;
+ struct irdp_interface *irdp=&zi->irdp;
+ int size;
+ int pref;
+ u_int16_t checksum;
+
+ pref = get_pref(irdp, p);
+
+ stream_putc (s, ICMP_ROUTERADVERT); /* Type. */
+ stream_putc (s, 0); /* Code. */
+ stream_putw (s, 0); /* Checksum. */
+ stream_putc (s, 1); /* Num address. */
+ stream_putc (s, 2); /* Address Entry Size. */
+
+ if(irdp->flags & IF_SHUTDOWN)
+ stream_putw (s, 0);
+ else
+ stream_putw (s, irdp->Lifetime);
+
+ stream_putl (s, htonl(p->u.prefix4.s_addr)); /* Router address. */
+ stream_putl (s, pref);
+
+ /* in_cksum return network byte order value */
+ size = 16;
+ checksum = in_cksum (s->data, size);
+ stream_putw_at (s, 2, htons(checksum));
+
+ return size;
+}
+
+void irdp_send(struct interface *ifp,
+ struct prefix *p,
+ struct stream *s)
+{
+ struct zebra_if *zi=ifp->info;
+ struct irdp_interface *irdp=&zi->irdp;
+ u_int32_t dst;
+ u_int32_t ttl=1;
+
+ if (! (ifp->flags & IFF_UP)) return;
+
+ if (irdp->flags & IF_BROADCAST)
+ dst =INADDR_BROADCAST ;
+ else
+ dst = htonl(INADDR_ALLHOSTS_GROUP);
+
+ if(irdp->flags & IF_DEBUG_MESSAGES)
+ zlog_warn("IRDP: TX Advert on %s %s/%d Holdtime=%d Preference=%d",
+ ifp->name,
+ inet_ntoa(p->u.prefix4),
+ p->prefixlen,
+ irdp->flags & IF_SHUTDOWN? 0 : irdp->Lifetime,
+ get_pref(irdp, p));
+
+ send_packet (ifp, s, dst, p, ttl);
+}
+
+void irdp_advertisement (struct interface *ifp,
+ struct prefix *p)
+{
+ struct stream *s;
+ s = stream_new (128);
+ make_advertisement_packet (ifp, p, s);
+ irdp_send(ifp, p, s);
+}
+
+int irdp_send_thread(struct thread *t_advert)
+{
+ u_int32_t timer, tmp;
+ struct interface *ifp = THREAD_ARG (t_advert);
+ struct zebra_if *zi=ifp->info;
+ struct irdp_interface *irdp=&zi->irdp;
+ struct prefix *p;
+ listnode node;
+ struct connected *ifc;
+
+ irdp->flags &= ~IF_SOLICIT;
+
+ if(ifp->connected)
+ for (node = listhead (ifp->connected); node; nextnode (node)) {
+ ifc = getdata (node);
+
+ p = ifc->address;
+
+ irdp_advertisement(ifp, p);
+ irdp->irdp_sent++;
+
+ }
+
+ tmp = irdp->MaxAdvertInterval-irdp->MinAdvertInterval;
+ timer = (random () % tmp ) + 1;
+ timer = irdp->MinAdvertInterval + timer;
+
+ if(irdp->irdp_sent < MAX_INITIAL_ADVERTISEMENTS &&
+ timer > MAX_INITIAL_ADVERT_INTERVAL )
+ timer= MAX_INITIAL_ADVERT_INTERVAL;
+
+ if(irdp->flags & IF_DEBUG_MISC)
+ zlog_warn("IRDP: New timer for %s set to %u\n", ifp->name, timer);
+
+ irdp->t_advertise = thread_add_timer(zebrad.master, irdp_send_thread, ifp, timer);
+ return 0;
+}
+
+void irdp_advert_off(struct interface *ifp)
+{
+ struct zebra_if *zi=ifp->info;
+ struct irdp_interface *irdp=&zi->irdp;
+ listnode node;
+ int i;
+ struct connected *ifc;
+ struct prefix *p;
+
+ if(irdp->t_advertise) thread_cancel(irdp->t_advertise);
+ irdp->t_advertise = NULL;
+
+ if(ifp->connected)
+ for (node = listhead (ifp->connected); node; nextnode (node)) {
+ ifc = getdata (node);
+
+ p = ifc->address;
+
+ /* Output some packets with Lifetime 0
+ we should add a wait...
+ */
+
+ for(i=0; i< IRDP_LAST_ADVERT_MESSAGES; i++) {
+
+ irdp->irdp_sent++;
+ irdp_advertisement(ifp, p);
+ }
+ }
+}
+
+
+void process_solicit (struct interface *ifp)
+{
+ struct zebra_if *zi=ifp->info;
+ struct irdp_interface *irdp=&zi->irdp;
+ u_int32_t timer;
+
+ /* When SOLICIT is active we reject further incoming solicits
+ this keeps down the answering rate so we don't have think
+ about DoS attacks here. */
+
+ if( irdp->flags & IF_SOLICIT) return;
+
+ irdp->flags |= IF_SOLICIT;
+ if(irdp->t_advertise) thread_cancel(irdp->t_advertise);
+ irdp->t_advertise = NULL;
+
+ timer = (random () % MAX_RESPONSE_DELAY) + 1;
+
+ irdp->t_advertise = thread_add_timer(zebrad.master,
+ irdp_send_thread,
+ ifp,
+ timer);
+}
+
+void irdp_finish()
+{
+
+ listnode node;
+ struct interface *ifp;
+ struct zebra_if *zi;
+ struct irdp_interface *irdp;
+
+ zlog_warn("IRDP: Received shutdown notification.");
+
+ for (node = listhead (iflist); node; node = nextnode (node))
+ {
+ ifp = getdata(node);
+ zi= ifp->info;
+ if(! zi) continue;
+ irdp = &zi->irdp;
+ if(!irdp) continue;
+
+ if(irdp->flags & IF_ACTIVE ) {
+ irdp->flags |= IF_SHUTDOWN;
+ irdp_advert_off(ifp);
+ }
+ }
+}
+
+void irdp_init()
+{
+ irdp_sock_init();
+ irdp_if_init ();
+}
+
+
+
+#endif /* HAVE_IRDP */
+
+
+
+