IPv4/IPv6 integrated socket code.

16 files changed, 1284 insertions, 1190 deletions

diff --git a/client/birdc.c b/client/birdc.c
index 6d4c86a9..ccf758be 100644
--- a/client/birdc.c
+++ b/client/birdc.c
@@ -19,7 +19,6 @@
 #include "lib/resource.h"
 #include "lib/string.h"
 #include "client/client.h"
-#include "sysdep/unix/unix.h"
 
 static int input_hidden_end;
 static int prompt_active;
diff --git a/lib/printf.c b/lib/printf.c
index 41e1cc0d..ebecc140 100644
--- a/lib/printf.c
+++ b/lib/printf.c
@@ -221,6 +221,16 @@ int bvsnprintf(char *buf, int size, const char *fmt, va_list args)
 			continue;
 
 		case 'm':
+			if (flags & SPECIAL) {
+				if (!errno)
+					continue;
+				if (size < 2)
+					return -1;
+				*str++ = ':';
+				*str++ = ' ';
+				start += 2;
+				size -= 2;
+			}
 			s = strerror(errno);
 			goto str;
 		case 'M':
diff --git a/lib/socket.h b/lib/socket.h
index 894d5561..f1fffa94 100644
--- a/lib/socket.h
+++ b/lib/socket.h
@@ -10,6 +10,7 @@
 #define _BIRD_SOCKET_H_
 
 #include <errno.h>
+// #include <sys/socket.h>
 
 #include "lib/resource.h"
 
@@ -43,17 +44,21 @@ typedef struct birdsock {
   unsigned lifindex;			/* local interface that received the datagram */
   /* laddr and lifindex are valid only if SKF_LADDR_RX flag is set to request it */
 
+  int af;				/* Address family (AF_INET, AF_INET6 or 0 for non-IP) of fd */
   int fd;				/* System-dependent data */
   int index;				/* Index in poll buffer */
+  int rcv_ttl;				/* TTL of last received datagram */
   node n;
   void *rbuf_alloc, *tbuf_alloc;
-  char *password;				/* Password for MD5 authentication */
+  char *password;			/* Password for MD5 authentication */
+  char *err;				/* Error message */
 } sock;
 
 sock *sock_new(pool *);			/* Allocate new socket */
 #define sk_new(X) sock_new(X)		/* Wrapper to avoid name collision with OpenSSL */
 
 int sk_open(sock *);			/* Open socket */
+int sk_rx_ready(sock *s);
 int sk_send(sock *, unsigned len);	/* Send data, <0=err, >0=ok, 0=sleep */
 int sk_send_to(sock *, unsigned len, ip_addr to, unsigned port); /* sk_send to given destination */
 void sk_reallocate(sock *);		/* Free and allocate tbuf & rbuf */
@@ -61,39 +66,41 @@ void sk_set_rbsize(sock *s, uint val);	/* Resize RX buffer */
 void sk_set_tbsize(sock *s, uint val);	/* Resize TX buffer, keeping content */
 void sk_set_tbuf(sock *s, void *tbuf);	/* Switch TX buffer, NULL-> return to internal */
 void sk_dump_all(void);
-int sk_set_ttl(sock *s, int ttl);	/* Set transmit TTL for given socket */
-int sk_set_min_ttl(sock *s, int ttl);	/* Set minimal accepted TTL for given socket */
 
-/* Add or remove security associations for given passive socket */
-int sk_set_md5_auth(sock *s, ip_addr a, struct iface *ifa, char *passwd);
-int sk_rx_ready(sock *s);
+static inline int sk_send_buffer_empty(sock *sk)
+{ return sk->tbuf == sk->tpos; }
 
-/* Prepare UDP or IP socket to multicasting. s->iface and s->ttl must be set */
-int sk_setup_multicast(sock *s);	
-int sk_join_group(sock *s, ip_addr maddr);
-int sk_leave_group(sock *s, ip_addr maddr);
 
 #ifdef IPV6
-int sk_set_ipv6_checksum(sock *s, int offset);
-int sk_set_icmp_filter(sock *s, int p1, int p2);
+#define sk_is_ipv4(X) 0
+#define sk_is_ipv6(X) 1
+#else
+#define sk_is_ipv4(X) 1
+#define sk_is_ipv6(X) 0
 #endif
 
-int sk_set_broadcast(sock *s, int enable);
 
-static inline int
-sk_send_buffer_empty(sock *sk)
-{
-	return sk->tbuf == sk->tpos;
-}
+int sk_setup_multicast(sock *s);	/* Prepare UDP or IP socket for multicasting */
+int sk_join_group(sock *s, ip_addr maddr);	/* Join multicast group on sk iface */
+int sk_leave_group(sock *s, ip_addr maddr);	/* Leave multicast group on sk iface */
+int sk_setup_broadcast(sock *s);
+int sk_set_ttl(sock *s, int ttl);	/* Set transmit TTL for given socket */
+int sk_set_min_ttl(sock *s, int ttl);	/* Set minimal accepted TTL for given socket */
+int sk_set_md5_auth(sock *s, ip_addr a, struct iface *ifa, char *passwd);
+int sk_set_ipv6_checksum(sock *s, int offset);
+int sk_set_icmp6_filter(sock *s, int p1, int p2);
+void sk_log_error(sock *s, const char *p);
+
+extern int sk_priority_control;		/* Suggested priority for control traffic, should be sysdep define */
 
-extern int sk_priority_control;	/* Suggested priority for control traffic, should be sysdep define */
 
 /* Socket flags */
 
-#define SKF_V6ONLY	1	/* Use IPV6_V6ONLY socket option */
-#define SKF_LADDR_RX	2	/* Report local address for RX packets */
-#define SKF_TTL_RX	4	/* Report TTL / Hop Limit for RX packets */
-#define SKF_BIND	8	/* Bind datagram socket to given source address */
+#define SKF_V4ONLY	0x01	/* Use IPv4 for IP sockets */
+#define SKF_V6ONLY	0x02	/* Use IPV6_V6ONLY socket option */
+#define SKF_LADDR_RX	0x04	/* Report local address for RX packets */
+#define SKF_TTL_RX	0x08	/* Report TTL / Hop Limit for RX packets */
+#define SKF_BIND	0x10	/* Bind datagram socket to given source address */
 
 #define SKF_THREAD	0x100	/* Socked used in thread, Do not add to main loop */
 #define SKF_TRUNCATED	0x200	/* Received packet was truncated, set by IO layer */
diff --git a/proto/bfd/packets.c b/proto/bfd/packets.c
index 964172d8..49b69bed 100644
--- a/proto/bfd/packets.c
+++ b/proto/bfd/packets.c
@@ -101,8 +101,8 @@ bfd_rx_hook(sock *sk, int len)
   uint err_val = 0;
   char fb[8];
 
-  if ((sk->sport == BFD_CONTROL_PORT) && (sk->ttl < 255))
-    DROP("wrong TTL", sk->ttl);
+  if ((sk->sport == BFD_CONTROL_PORT) && (sk->rcv_ttl < 255))
+    DROP("wrong TTL", sk->rcv_ttl);
 
   if (len < BFD_BASE_LEN)
     DROP("too short", len);
@@ -209,6 +209,7 @@ bfd_open_rx_sk(struct bfd_proto *p, int multihop)
   return sk;
 
  err:
+  sk_log_error(sk, p->p.name);
   rfree(sk);
   return NULL;
 }
@@ -243,6 +244,7 @@ bfd_open_tx_sk(struct bfd_proto *p, ip_addr local, struct iface *ifa)
   return sk;
 
  err:
+  sk_log_error(sk, p->p.name);
   rfree(sk);
   return NULL;
 }
diff --git a/proto/bgp/bgp.c b/proto/bgp/bgp.c
index ca619f31..b6239971 100644
--- a/proto/bgp/bgp.c
+++ b/proto/bgp/bgp.c
@@ -106,14 +106,11 @@ bgp_open(struct bgp_proto *p)
   struct config *cfg = p->cf->c.global;
   int errcode;
 
-  bgp_counter++;
-
   if (!bgp_listen_sk)
     bgp_listen_sk = bgp_setup_listen_sk(cfg->listen_bgp_addr, cfg->listen_bgp_port, cfg->listen_bgp_flags);
 
   if (!bgp_listen_sk)
     {
-      bgp_counter--;
       errcode = BEM_NO_SOCKET;
       goto err;
     }
@@ -121,16 +118,16 @@ bgp_open(struct bgp_proto *p)
   if (!bgp_linpool)
     bgp_linpool = lp_new(&root_pool, 4080);
 
+  bgp_counter++;
+
   if (p->cf->password)
-    {
-      int rv = sk_set_md5_auth(bgp_listen_sk, p->cf->remote_ip, p->cf->iface, p->cf->password);
-      if (rv < 0)
-	{
-	  bgp_close(p, 0);
-	  errcode = BEM_INVALID_MD5;
-	  goto err;
-	}
-    }
+    if (sk_set_md5_auth(bgp_listen_sk, p->cf->remote_ip, p->cf->iface, p->cf->password) < 0)
+      {
+	sk_log_error(bgp_listen_sk, p->p.name);
+	bgp_close(p, 0);
+	errcode = BEM_INVALID_MD5;
+	goto err;
+      }
 
   return 0;
 
@@ -194,7 +191,8 @@ bgp_close(struct bgp_proto *p, int apply_md5)
   bgp_counter--;
 
   if (p->cf->password && apply_md5)
-    sk_set_md5_auth(bgp_listen_sk, p->cf->remote_ip, p->cf->iface, NULL);
+    if (sk_set_md5_auth(bgp_listen_sk, p->cf->remote_ip, p->cf->iface, NULL) < 0)
+      sk_log_error(bgp_listen_sk, p->p.name);
 
   if (!bgp_counter)
     {
@@ -697,25 +695,21 @@ bgp_connect(struct bgp_proto *p)	/* Enter Connect state and start establishing c
   bgp_conn_set_state(conn, BS_CONNECT);
 
   if (sk_open(s) < 0)
-    {
-      bgp_sock_err(s, 0);
-      return;
-    }
+    goto err;
 
   /* Set minimal receive TTL if needed */
   if (p->cf->ttl_security)
-  {
-    DBG("Setting minimum received TTL to %d", 256 - hops);
     if (sk_set_min_ttl(s, 256 - hops) < 0)
-    {
-      log(L_ERR "TTL security configuration failed, closing session");
-      bgp_sock_err(s, 0);
-      return;
-    }
-  }
+      goto err;
 
   DBG("BGP: Waiting for connect success\n");
   bgp_start_timer(conn->connect_retry_timer, p->cf->connect_retry_time);
+  return;
+
+ err:
+  sk_log_error(s, p->p.name);
+  bgp_sock_err(s, 0);
+  return;
 }
 
 /**
@@ -760,32 +754,33 @@ bgp_incoming_connection(sock *sk, int dummy UNUSED)
 		      sk->dport, acc ? "accepted" : "rejected");
 
 	    if (!acc)
-	      goto err;
+	      goto reject;
 
 	    int hops = p->cf->multihop ? : 1;
+
+	    if (sk_set_ttl(sk, p->cf->ttl_security ? 255 : hops) < 0)
+	      goto err;
+
 	    if (p->cf->ttl_security)
-	    {
-	      /* TTL security support */
-	      if ((sk_set_ttl(sk, 255) < 0) ||
-		  (sk_set_min_ttl(sk, 256 - hops) < 0))
-	      {
-		log(L_ERR "TTL security configuration failed, closing session");
+	      if (sk_set_min_ttl(sk, 256 - hops) < 0)
 		goto err;
-	      }
-	    }
-	    else
-	      sk_set_ttl(sk, hops);
 
 	    bgp_setup_conn(p, &p->incoming_conn);
 	    bgp_setup_sk(&p->incoming_conn, sk);
 	    bgp_send_open(&p->incoming_conn);
 	    return 0;
+
+	  err:
+	    sk_log_error(sk, p->p.name);
+	    log(L_ERR "%s: Incoming connection aborted", p->p.name);
+	    rfree(sk);
+	    return 0;
 	  }
       }
 
   log(L_WARN "BGP: Unexpected connect from unknown address %I%J (port %d)",
       sk->daddr, ipa_has_link_scope(sk->daddr) ? sk->iface : NULL, sk->dport);
- err:
+ reject:
   rfree(sk);
   return 0;
 }
@@ -816,13 +811,15 @@ bgp_setup_listen_sk(ip_addr addr, unsigned port, u32 flags)
   s->err_hook = bgp_listen_sock_err;
 
   if (sk_open(s) < 0)
-    {
-      log(L_ERR "BGP: Unable to open listening socket");
-      rfree(s);
-      return NULL;
-    }
+    goto err;
 
   return s;
+
+ err:
+  sk_log_error(s, "BGP");
+  log(L_ERR "BGP: Cannot open listening socket");
+  rfree(s);
+  return NULL;
 }
 
 static void
diff --git a/proto/ospf/iface.c b/proto/ospf/iface.c
index f4d9be55..50cf15e2 100644
--- a/proto/ospf/iface.c
+++ b/proto/ospf/iface.c
@@ -90,6 +90,8 @@ find_nbma_node_in(list *nnl, ip_addr ip)
 static int
 ospf_sk_open(struct ospf_iface *ifa)
 {
+  struct proto_ospf *po = ifa->oa->po;
+
   sock *sk = sk_new(ifa->pool);
   sk->type = SK_IP;
   sk->dport = OSPF_PROTO;
@@ -121,7 +123,7 @@ ospf_sk_open(struct ospf_iface *ifa)
     {
       ifa->all_routers = ifa->addr->brd;
 
-      if (sk_set_broadcast(sk, 1) < 0)
+      if (sk_setup_broadcast(sk) < 0)
         goto err;
     }
     else
@@ -141,6 +143,7 @@ ospf_sk_open(struct ospf_iface *ifa)
   return 1;
 
  err:
+  sk_log_error(sk, po->proto.name);
   rfree(sk);
   return 0;
 }
@@ -151,7 +154,9 @@ ospf_sk_join_dr(struct ospf_iface *ifa)
   if (ifa->sk_dr)
     return;
 
-  sk_join_group(ifa->sk, AllDRouters);
+  if (sk_join_group(ifa->sk, AllDRouters) < 0)
+    sk_log_error(ifa->sk, ifa->oa->po->proto.name);
+
   ifa->sk_dr = 1;
 }
 
@@ -161,15 +166,15 @@ ospf_sk_leave_dr(struct ospf_iface *ifa)
   if (!ifa->sk_dr)
     return;
 
-  sk_leave_group(ifa->sk, AllDRouters);
+  if (sk_leave_group(ifa->sk, AllDRouters) < 0)
+    sk_log_error(ifa->sk, ifa->oa->po->proto.name);
+
   ifa->sk_dr = 0;
 }
 
 void
 ospf_open_vlink_sk(struct proto_ospf *po)
 {
-  struct proto *p = &po->proto;
-
   sock *sk = sk_new(po->proto.pool);
   sk->type = SK_IP;
   sk->dport = OSPF_PROTO;
@@ -197,8 +202,9 @@ ospf_open_vlink_sk(struct proto_ospf *po)
   return;
 
  err:
+  sk_log_error(sk, po->proto.name);
+  log(L_ERR "%s: Cannot open virtual link socket", po->proto.name);
   rfree(sk);
-  log(L_ERR "%s: Cannot open virtual link socket", p->name);
 }
 
 static void
@@ -463,7 +469,7 @@ ospf_iface_add(struct object_lock *lock)
   /* Open socket if interface is not stub */
   if (! ifa->stub && ! ospf_sk_open(ifa))
   {
-    log(L_ERR "%s: Socket open failed on interface %s, declaring as stub", p->name, ifa->ifname);
+    log(L_ERR "%s: Cannot open socket for %s, declaring as stub", p->name, ifa->ifname);
     ifa->ioprob = OSPF_I_SK;
     ifa->stub = 1;
   }
diff --git a/proto/ospf/packet.c b/proto/ospf/packet.c
index cd4b8a97..1240b05c 100644
--- a/proto/ospf/packet.c
+++ b/proto/ospf/packet.c
@@ -308,9 +308,9 @@ ospf_rx_hook(sock *sk, int size)
     return 1;
   }
 
-  if (ifa->check_ttl && (sk->ttl < 255))
+  if (ifa->check_ttl && (sk->rcv_ttl < 255))
   {
-    log(L_ERR "%s%I - TTL %d (< 255)", mesg, sk->faddr, sk->ttl);
+    log(L_ERR "%s%I - TTL %d (< 255)", mesg, sk->faddr, sk->rcv_ttl);
     return 1;
   }
 
diff --git a/proto/radv/packets.c b/proto/radv/packets.c
index 997fda3d..1d7e04f4 100644
--- a/proto/radv/packets.c
+++ b/proto/radv/packets.c
@@ -416,11 +416,11 @@ radv_sk_open(struct radv_iface *ifa)
   sk->data = ifa;
   sk->flags = SKF_LADDR_RX;
 
-  if (sk_open(sk) != 0)
+  if (sk_open(sk) < 0)
     goto err;
 
   /* We want listen just to ICMPv6 messages of type RS and RA */
-  if (sk_set_icmp_filter(sk, ICMPV6_RS, ICMPV6_RA) < 0)
+  if (sk_set_icmp6_filter(sk, ICMPV6_RS, ICMPV6_RA) < 0)
     goto err;
 
   if (sk_setup_multicast(sk) < 0)
@@ -433,6 +433,7 @@ radv_sk_open(struct radv_iface *ifa)
   return 1;
 
  err:
+  sk_log_error(sk, ifa->ra->p.name);
   rfree(sk);
   return 0;
 }
diff --git a/proto/rip/rip.c b/proto/rip/rip.c
index 9730df77..bc9ffc5f 100644
--- a/proto/rip/rip.c
+++ b/proto/rip/rip.c
@@ -483,10 +483,10 @@ rip_rx(sock *s, int size)
   iface = i->iface;
 #endif
 
-  if (i->check_ttl && (s->ttl < 255))
+  if (i->check_ttl && (s->rcv_ttl < 255))
   {
     log( L_REMOTE "%s: Discarding packet with TTL %d (< 255) from %I on %s",
-	 p->name, s->ttl, s->faddr, i->iface->name);
+	 p->name, s->rcv_ttl, s->faddr, i->iface->name);
     return 1;
   }
 
@@ -733,7 +733,7 @@ new_iface(struct proto *p, struct iface *new, unsigned long flags, struct iface_
       log( L_WARN "%s: interface %s is too strange for me", p->name, rif->iface->name );
   } else {
 
-    if (sk_open(rif->sock)<0)
+    if (sk_open(rif->sock) < 0)
       goto err;
 
     if (rif->multicast)
@@ -745,7 +745,7 @@ new_iface(struct proto *p, struct iface *new, unsigned long flags, struct iface_
       }
     else
       {
-	if (sk_set_broadcast(rif->sock, 1) < 0)
+	if (sk_setup_broadcast(rif->sock) < 0)
 	  goto err;
       }
   }
@@ -755,7 +755,8 @@ new_iface(struct proto *p, struct iface *new, unsigned long flags, struct iface_
   return rif;
 
  err:
-  log( L_ERR "%s: could not create socket for %s", p->name, rif->iface ? rif->iface->name : "(dummy)" );
+  sk_log_error(rif->sock, p->name);
+  log(L_ERR "%s: Cannot open socket for %s", p->name, rif->iface ? rif->iface->name : "(dummy)" );
   if (rif->iface) {
     rfree(rif->sock);
     mb_free(rif);
diff --git a/sysdep/bsd/krt-sock.c b/sysdep/bsd/krt-sock.c
index aaeb7d90..26710375 100644
--- a/sysdep/bsd/krt-sock.c
+++ b/sysdep/bsd/krt-sock.c
@@ -251,9 +251,9 @@ krt_send_route(struct krt_proto *p, int cmd, rte *e)
     _I0(gw) = 0xfe800000 | (i->index & 0x0000ffff);
 #endif
 
-  fill_in_sockaddr(&dst, net->n.prefix, NULL, 0);
-  fill_in_sockaddr(&mask, ipa_mkmask(net->n.pxlen), NULL, 0);
-  fill_in_sockaddr(&gate, gw, NULL, 0);
+  sockaddr_fill(&dst,  BIRD_AF, net->n.prefix, NULL, 0);
+  sockaddr_fill(&mask, BIRD_AF, ipa_mkmask(net->n.pxlen), NULL, 0);
+  sockaddr_fill(&gate, BIRD_AF, gw, NULL, 0);
 
   switch (a->dest)
   {
@@ -280,7 +280,7 @@ krt_send_route(struct krt_proto *p, int cmd, rte *e)
           return -1;
         }
 
-        fill_in_sockaddr(&gate, i->addr->ip, NULL, 0);
+	sockaddr_fill(&dst, BIRD_AF, i->addr->ip, NULL, 0);
         msg.rtm.rtm_addrs |= RTA_GATEWAY;
       }
       break;
@@ -366,20 +366,16 @@ krt_read_route(struct ks_msg *msg, struct krt_proto *p, int scan)
   GETADDR(&gate, RTA_GATEWAY);
   GETADDR(&mask, RTA_NETMASK);
 
-  if (sa_family_check(&dst))
-    get_sockaddr(&dst, &idst, NULL, NULL, 0);
-  else
+  if (dst.sa.sa_family != BIRD_AF)
     SKIP("invalid DST");
 
-  /* We will check later whether we have valid gateway addr */
-  if (sa_family_check(&gate))
-    get_sockaddr(&gate, &igate, NULL, NULL, 0);
-  else
-    igate = IPA_NONE;
+  idst  = ipa_from_sa(&dst);
+  imask = ipa_from_sa(&mask);
+  igate = (gate.sa.sa_family == BIRD_AF) ? ipa_from_sa(&gate) : IPA_NONE;
 
   /* We do not test family for RTA_NETMASK, because BSD sends us
      some strange values, but interpreting them as IPv4/IPv6 works */
-  get_sockaddr(&mask, &imask, NULL, NULL, 0);
+
 
   int c = ipa_classify_net(idst);
   if ((c < 0) || !(c & IADDR_HOST) || ((c & IADDR_SCOPE_MASK) <= SCOPE_LINK))
@@ -648,12 +644,13 @@ krt_read_addr(struct ks_msg *msg, int scan)
   GETADDR (&brd, RTA_BRD);
 
   /* Some other family address */
-  if (!sa_family_check(&addr))
+  if (addr.sa.sa_family != BIRD_AF)
     return;
 
-  get_sockaddr(&addr, &iaddr, NULL, NULL, 0);
-  get_sockaddr(&mask, &imask, NULL, NULL, 0);
-  get_sockaddr(&brd, &ibrd, NULL, NULL, 0);
+  iaddr = ipa_from_sa(&addr);
+  imask = ipa_from_sa(&mask);
+  ibrd  = ipa_from_sa(&brd);
+
 
   if ((masklen = ipa_mklen(imask)) < 0)
   {
@@ -806,7 +803,7 @@ krt_sysctl_scan(struct proto *p, int cmd, int table_id)
   mib[0] = CTL_NET;
   mib[1] = PF_ROUTE;
   mib[2] = 0;
-  mib[3] = BIRD_PF;
+  mib[3] = BIRD_AF;
   mib[4] = cmd;
   mib[5] = 0;
   mcnt = 6;
diff --git a/sysdep/bsd/sysio.h b/sysdep/bsd/sysio.h
index e45deb6f..fa3969bd 100644
--- a/sysdep/bsd/sysio.h
+++ b/sysdep/bsd/sysio.h
@@ -1,11 +1,16 @@
 /*
- *	BIRD Internet Routing Daemon -- NetBSD Multicasting and Network Includes
+ *	BIRD Internet Routing Daemon -- BSD Multicasting and Network Includes
  *
  *	(c) 2004       Ondrej Filip <feela@network.cz>
  *
  *	Can be freely distributed and used under the terms of the GNU GPL.
  */
 
+#include <net/if_dl.h>
+#include <netinet/in_systm.h> // Workaround for some BSDs
+#include <netinet/ip.h>
+
+
 #ifdef __NetBSD__
 
 #ifndef IP_RECVTTL
@@ -22,173 +27,117 @@
 #define TCP_MD5SIG	TCP_SIGNATURE_ENABLE
 #endif
 
-#ifdef IPV6
 
-static inline void
-set_inaddr(struct in6_addr * ia, ip_addr a)
-{
-  ipa_hton(a);
-  memcpy(ia, &a, sizeof(a));
-}
+#define SA_LEN(x) (x).sa.sa_len
 
-static inline void
-get_inaddr(ip_addr *a, struct in6_addr *ia)
-{
-  memcpy(a, ia, sizeof(*a));
-  ipa_ntoh(*a);
-}
-
-
-#else
-
-#include <net/if.h>
-#include <net/if_dl.h>
-#include <netinet/in_systm.h> // Workaround for some BSDs
-#include <netinet/ip.h>
-
-static inline void
-set_inaddr(struct in_addr * ia, ip_addr a)
-{
-  ipa_hton(a);
-  memcpy(&ia->s_addr, &a, sizeof(a));
-}
-
-static inline void
-get_inaddr(ip_addr *a, struct in_addr *ia)
-{
-  memcpy(a, &ia->s_addr, sizeof(*a));
-  ipa_ntoh(*a);
-}
 
+/*
+ *	BSD IPv4 multicast syscalls
+ */
 
-/* BSD Multicast handling for IPv4 */
+#define INIT_MREQ4(maddr,ifa) \
+  { .imr_multiaddr = ipa_to_in4(maddr), .imr_interface = ipa_to_in4(ifa->addr->ip) }
 
-static inline char *
-sysio_setup_multicast(sock *s)
+static inline int
+sk_setup_multicast4(sock *s)
 {
-	struct in_addr m;
-	u8 zero = 0;
-	u8 ttl = s->ttl;
+  struct in_addr ifa = ipa_to_in4(s->iface->addr->ip);
+  u8 ttl = s->ttl;
+  u8 n = 0;
 
-	if (setsockopt(s->fd, IPPROTO_IP, IP_MULTICAST_LOOP, &zero, sizeof(zero)) < 0)
-		return "IP_MULTICAST_LOOP";
+  /* This defines where should we send _outgoing_ multicasts */
+  if (setsockopt(s->fd, IPPROTO_IP, IP_MULTICAST_IF, &ifa, sizeof(ifa)) < 0)
+    ERR("IP_MULTICAST_IF");
 
-	if (setsockopt(s->fd, IPPROTO_IP, IP_MULTICAST_TTL, &ttl, sizeof(ttl)) < 0)
-		return "IP_MULTICAST_TTL";
+  if (setsockopt(s->fd, IPPROTO_IP, IP_MULTICAST_TTL, &ttl, sizeof(ttl)) < 0)
+    ERR("IP_MULTICAST_TTL");
 
-	/* This defines where should we send _outgoing_ multicasts */
-        set_inaddr(&m, s->iface->addr->ip);
-	if (setsockopt(s->fd, IPPROTO_IP, IP_MULTICAST_IF, &m, sizeof(m)) < 0)
-		return "IP_MULTICAST_IF";
+  if (setsockopt(s->fd, IPPROTO_IP, IP_MULTICAST_LOOP, &n, sizeof(n)) < 0)
+    ERR("IP_MULTICAST_LOOP");
 
-	return NULL;
+  return 0;
 }
 
-
-static inline char *
-sysio_join_group(sock *s, ip_addr maddr)
+static inline int
+sk_join_group4(sock *s, ip_addr maddr)
 {
-	struct ip_mreq mreq;
+  struct ip_mreq mr = INIT_MREQ4(maddr, s->iface);
 
-	bzero(&mreq, sizeof(mreq));
-	set_inaddr(&mreq.imr_interface, s->iface->addr->ip);
-	set_inaddr(&mreq.imr_multiaddr, maddr);
+  if (setsockopt(s->fd, IPPROTO_IP, IP_ADD_MEMBERSHIP, &mr, sizeof(mr)) < 0)
+    ERR("IP_ADD_MEMBERSHIP");
 
-	/* And this one sets interface for _receiving_ multicasts from */
-	if (setsockopt(s->fd, IPPROTO_IP, IP_ADD_MEMBERSHIP, &mreq, sizeof(mreq)) < 0)
-		return "IP_ADD_MEMBERSHIP";
-
-	return NULL;
+  return 0;
 }
 
-static inline char *
-sysio_leave_group(sock *s, ip_addr maddr)
+static inline int
+sk_leave_group4(sock *s, ip_addr maddr)
 {
-	struct ip_mreq mreq;
+  struct ip_mreq mr = INIT_MREQ4(maddr, s->iface);
 
-	bzero(&mreq, sizeof(mreq));
-	set_inaddr(&mreq.imr_interface, s->iface->addr->ip);
-	set_inaddr(&mreq.imr_multiaddr, maddr);
+  if (setsockopt(s->fd, IPPROTO_IP, IP_DROP_MEMBERSHIP, &mr, sizeof(mr)) < 0)
+    ERR("IP_ADD_MEMBERSHIP");
 
-	/* And this one sets interface for _receiving_ multicasts from */
-	if (setsockopt(s->fd, IPPROTO_IP, IP_DROP_MEMBERSHIP, &mreq, sizeof(mreq)) < 0)
-		return "IP_DROP_MEMBERSHIP";
-
-	return NULL;
+  return 0;
 }
 
 
-/* BSD RX/TX packet info handling for IPv4 */
-/* it uses IP_RECVDSTADDR / IP_RECVIF socket options instead of IP_PKTINFO */
+/*
+ *	BSD IPv4 packet control messages
+ */
 
-#define CMSG_RX_SPACE (CMSG_SPACE(sizeof(struct in_addr)) + \
-		       CMSG_SPACE(sizeof(struct sockaddr_dl)) + \
-		       CMSG_SPACE(sizeof(char)))
-#define CMSG_TX_SPACE CMSG_SPACE(sizeof(struct in_addr))
+/* It uses IP_RECVDSTADDR / IP_RECVIF socket options instead of IP_PKTINFO */
 
-static char *
-sysio_register_cmsgs(sock *s)
-{
-  int ok = 1;
-  if (s->flags & SKF_LADDR_RX)
-  {
-    if (setsockopt(s->fd, IPPROTO_IP, IP_RECVDSTADDR, &ok, sizeof(ok)) < 0)
-      return "IP_RECVDSTADDR";
+#define CMSG4_SPACE_PKTINFO (CMSG_SPACE(sizeof(struct in_addr)) + \
+			     CMSG_SPACE(sizeof(struct sockaddr_dl)))
+#define CMSG4_SPACE_TTL CMSG_SPACE(sizeof(char))
 
-    if (setsockopt(s->fd, IPPROTO_IP, IP_RECVIF, &ok, sizeof(ok)) < 0)
-      return "IP_RECVIF";
-  }
+static inline int
+sk_request_cmsg4_pktinfo(sock *s)
+{
+  int y = 1;
 
-  if ((s->flags & SKF_TTL_RX) &&
-      (setsockopt(s->fd, IPPROTO_IP, IP_RECVTTL, &ok, sizeof(ok)) < 0))
-    return "IP_RECVTTL";
+  if (setsockopt(s->fd, IPPROTO_IP, IP_RECVDSTADDR, &y, sizeof(y)) < 0)
+    ERR("IP_RECVDSTADDR");
 
+  if (setsockopt(s->fd, IPPROTO_IP, IP_RECVIF, &y, sizeof(y)) < 0)
+    ERR("IP_RECVIF");
 
-  return NULL;
+  return 0;
 }
 
-static inline void
-sysio_process_rx_cmsgs(sock *s, struct msghdr *msg)
+static inline int
+sk_request_cmsg4_ttl(sock *s)
 {
-  struct cmsghdr *cm;
-  struct in_addr *ra = NULL;
-  struct sockaddr_dl *ri = NULL;
-  unsigned char *ttl = NULL;
-
-  for (cm = CMSG_FIRSTHDR(msg); cm != NULL; cm = CMSG_NXTHDR(msg, cm))
-  {
-    if (cm->cmsg_level == IPPROTO_IP && cm->cmsg_type == IP_RECVDSTADDR)
-      ra = (struct in_addr *) CMSG_DATA(cm);
-
-    if (cm->cmsg_level == IPPROTO_IP && cm->cmsg_type == IP_RECVIF)
-      ri = (struct sockaddr_dl *) CMSG_DATA(cm);
-
-    if (cm->cmsg_level == IPPROTO_IP && cm->cmsg_type == IP_RECVTTL)
-      ttl = (unsigned char *) CMSG_DATA(cm);
-  }
+  int y = 1;
 
-  if (s->flags & SKF_LADDR_RX)
-  {
-    s->laddr = IPA_NONE;
-    s->lifindex = 0;
+  if (setsockopt(s->fd, IPPROTO_IP, IP_RECVTTL, &y, sizeof(y)) < 0)
+    ERR("IP_RECVTTL");
 
-    if (ra)
-      get_inaddr(&s->laddr, ra);
-    if (ri)
-      s->lifindex = ri->sdl_index;
-  }
+  return 0;
+}
 
-  if (s->flags & SKF_TTL_RX)
-    s->ttl = ttl ? *ttl : -1;
+static inline void
+sk_process_cmsg4_pktinfo(sock *s, struct cmsghdr *cm)
+{
+  if (cm->cmsg_type == IP_RECVDSTADDR)
+    s->laddr = ipa_from_in4(* (struct in_addr *) CMSG_DATA(cm));
 
-  // log(L_WARN "RX %I %d", s->laddr, s->lifindex);
+  if (cm->cmsg_type == IP_RECVIF)
+    s->lifindex = ((struct sockaddr_dl *) CMSG_DATA(cm))->sdl_index;
 }
 
-/* Unfortunately, IP_SENDSRCADDR does not work for raw IP sockets on BSD kernels */
+static inline void
+sk_process_cmsg4_ttl(sock *s, struct cmsghdr *cm)
+{
+  if (cm->cmsg_type == IP_RECVTTL)
+    s->rcv_ttl = * (unsigned char *) CMSG_DATA(cm);
+}
 
 static inline void
-sysio_prepare_tx_cmsgs(sock *s, struct msghdr *msg, void *cbuf, size_t cbuflen)
+sk_prepare_cmsgs4(sock *s, struct msghdr *msg, void *cbuf, size_t cbuflen)
 {
+  /* Unfortunately, IP_SENDSRCADDR does not work for raw IP sockets on BSD kernels */
+
 #ifdef IP_SENDSRCADDR
   struct cmsghdr *cm;
   struct in_addr *sa;
@@ -202,15 +151,14 @@ sysio_prepare_tx_cmsgs(sock *s, struct msghdr *msg, void *cbuf, size_t cbuflen)
   cm->cmsg_len = CMSG_LEN(sizeof(*sa));
 
   sa = (struct in_addr *) CMSG_DATA(cm);
-  set_inaddr(sa, s->saddr);
+  *sa = ipa_to_in4(s->saddr);
 
   msg->msg_controllen = cm->cmsg_len;
 #endif
 }
 
-
 static void
-fill_ip_header(sock *s, void *hdr, int dlen)
+sk_prepare_ip_header(sock *s, void *hdr, int dlen)
 {
   struct ip *ip = hdr;
 
@@ -222,8 +170,8 @@ fill_ip_header(sock *s, void *hdr, int dlen)
   ip->ip_len = 20 + dlen;
   ip->ip_ttl = (s->ttl < 0) ? 64 : s->ttl;
   ip->ip_p = s->dport;
-  set_inaddr(&ip->ip_src, s->saddr);
-  set_inaddr(&ip->ip_dst, s->daddr);
+  ip->ip_src = ipa_to_in4(s->saddr);
+  ip->ip_dst = ipa_to_in4(s->daddr);
 
 #ifdef __OpenBSD__
   /* OpenBSD expects ip_len in network order, other BSDs expect host order */
@@ -231,10 +179,11 @@ fill_ip_header(sock *s, void *hdr, int dlen)
 #endif
 }
 
-#endif
 
+/*
+ *	Miscellaneous BSD socket syscalls
+ */
 
-#include <netinet/tcp.h>
 #ifndef TCP_KEYLEN_MAX
 #define TCP_KEYLEN_MAX 80
 #endif
@@ -248,72 +197,69 @@ fill_ip_header(sock *s, void *hdr, int dlen)
  * management.
  */
 
-static int
-sk_set_md5_auth_int(sock *s, sockaddr *sa, char *passwd)
+int
+sk_set_md5_auth(sock *s, ip_addr a, struct iface *ifa, char *passwd)
 {
   int enable = 0;
-  if (passwd)
-    {
-      int len = strlen(passwd);
-
-      enable = len ? TCP_SIG_SPI : 0;
-
-      if (len > TCP_KEYLEN_MAX)
-	{
-	  log(L_ERR "MD5 password too long");
-	  return -1;
-	}
-    }
-
-  int rv = setsockopt(s->fd, IPPROTO_TCP, TCP_MD5SIG, &enable, sizeof(enable));
-
-  if (rv < 0) 
-    {
-      if (errno == ENOPROTOOPT)
-	log(L_ERR "Kernel does not support TCP MD5 signatures");
-      else
-	log(L_ERR "sk_set_md5_auth_int: setsockopt: %m");
-    }
-
-  return rv;
-}
 
+  if (passwd && *passwd)
+  {
+    int len = strlen(passwd);
+    enable = TCP_SIG_SPI;
+
+    if (len > TCP_KEYLEN_MAX)
+      ERR_MSG("MD5 password too long");
+  }
+
+  if (setsockopt(s->fd, IPPROTO_TCP, TCP_MD5SIG, &enable, sizeof(enable)) < 0)
+  {
+    if (errno == ENOPROTOOPT)
+      ERR_MSG("Kernel does not support TCP MD5 signatures");
+    else
+      ERR("TCP_MD5SIG");
+  }
 
-#ifndef IPV6
+  return 0;
+}
 
-static int
+static inline int
 sk_set_min_ttl4(sock *s, int ttl)
 {
   if (setsockopt(s->fd, IPPROTO_IP, IP_MINTTL, &ttl, sizeof(ttl)) < 0)
   {
     if (errno == ENOPROTOOPT)
-      log(L_ERR "Kernel does not support IPv4 TTL security");
+      ERR_MSG("Kernel does not support IPv4 TTL security");
     else
-      log(L_ERR "sk_set_min_ttl4: setsockopt: %m");
-
-    return -1;
+      ERR("IP_MINTTL");
   }
 
   return 0;
 }
 
-#else /* IPv6 */
-
-static int
+static inline int
 sk_set_min_ttl6(sock *s, int ttl)
 {
-  log(L_ERR "IPv6 TTL security not supported");
-  return -1;
+  ERR_MSG("Kernel does not support IPv6 TTL security");
 }
 
-#endif
+static inline int
+sk_disable_mtu_disc4(sock *s)
+{
+  /* TODO: Set IP_DONTFRAG to 0 ? */
+  return 0;
+}
 
+static inline int
+sk_disable_mtu_disc6(sock *s)
+{
+  /* TODO: Set IPV6_DONTFRAG to 0 ? */
+  return 0;
+}
 
 int sk_priority_control = -1;
 
-static int
+static inline int
 sk_set_priority(sock *s, int prio UNUSED)
 {
-  log(L_WARN "Socket priority not supported");
-  return -1;
+  ERR_MSG("Socket priority not supported");
 }
diff --git a/sysdep/linux/netlink.c b/sysdep/linux/netlink.c
index 7063e2ca..a0f85186 100644
--- a/sysdep/linux/netlink.c
+++ b/sysdep/linux/netlink.c
@@ -104,9 +104,9 @@ nl_request_dump(int cmd)
   req.nh.nlmsg_type = cmd;
   req.nh.nlmsg_len = sizeof(req);
   req.nh.nlmsg_flags = NLM_F_REQUEST | NLM_F_DUMP;
-  /* Is it important which PF_* is used for link-level interface scan?
-     It seems that some information is available only when PF_INET is used. */
-  req.g.rtgen_family = (cmd == RTM_GETLINK) ? PF_INET : BIRD_PF;
+  /* Is it important which AF_* is used for link-level interface scan?
+     It seems that some information is available only when AF_INET is used. */
+  req.g.rtgen_family = (cmd == RTM_GETLINK) ? AF_INET : BIRD_AF;
   nl_send(&nl_scan, &req.nh);
 }
 
@@ -1069,7 +1069,7 @@ nl_open_async(void)
   sk->type = SK_MAGIC;
   sk->rx_hook = nl_async_hook;
   sk->fd = fd;
-  if (sk_open(sk))
+  if (sk_open(sk) < 0)
     bug("Netlink: sk_open failed");
 }
 
diff --git a/sysdep/linux/sysio.h b/sysdep/linux/sysio.h
index dc807392..5fd75c90 100644
--- a/sysdep/linux/sysio.h
+++ b/sysdep/linux/sysio.h
@@ -6,232 +6,151 @@
  *	Can be freely distributed and used under the terms of the GNU GPL.
  */
 
-#include <net/if.h>
-
-#ifdef IPV6
-
-#ifndef IPV6_UNICAST_HOPS
-/* Needed on glibc 2.0 systems */
-#include <linux/in6.h>
-#define CONFIG_IPV6_GLIBC_20
-#endif
-
-static inline void
-set_inaddr(struct in6_addr *ia, ip_addr a)
-{
-  ipa_hton(a);
-  memcpy(ia, &a, sizeof(a));
-}
-
-static inline void
-get_inaddr(ip_addr *a, struct in6_addr *ia)
-{
-  memcpy(a, ia, sizeof(*a));
-  ipa_ntoh(*a);
-}
-
-#else
-
-static inline void
-set_inaddr(struct in_addr *ia, ip_addr a)
-{
-  ipa_hton(a);
-  memcpy(&ia->s_addr, &a, sizeof(a));
-}
-
-static inline void
-get_inaddr(ip_addr *a, struct in_addr *ia)
-{
-  memcpy(a, &ia->s_addr, sizeof(*a));
-  ipa_ntoh(*a);
-}
-
 
 #ifndef HAVE_STRUCT_IP_MREQN
 /* Several versions of glibc don't define this structure, so we have to do it ourselves */
 struct ip_mreqn
 {
-	struct in_addr	imr_multiaddr;		/* IP multicast address of group */
-	struct in_addr	imr_address;		/* local IP address of interface */
-	int		imr_ifindex;		/* Interface index */
+  struct in_addr imr_multiaddr;			/* IP multicast address of group */
+  struct in_addr imr_address;			/* local IP address of interface */
+  int		 imr_ifindex;			/* Interface index */
 };
 #endif
 
+#ifndef IP_MINTTL
+#define IP_MINTTL 21
+#endif
 
-static inline void fill_mreqn(struct ip_mreqn *m, ip_addr maddr, struct iface *ifa)
-{
-  bzero(m, sizeof(*m));
-  m->imr_ifindex = ifa->index;
-  set_inaddr(&m->imr_multiaddr, maddr);
-}
+#ifndef IPV6_TCLASS
+#define IPV6_TCLASS 67
+#endif
 
-static inline char *
-sysio_setup_multicast(sock *s)
-{
-  struct ip_mreqn m;
-  int zero = 0;
+#ifndef IPV6_MINHOPCOUNT
+#define IPV6_MINHOPCOUNT 73
+#endif
 
-  if (setsockopt(s->fd, SOL_IP, IP_MULTICAST_LOOP, &zero, sizeof(zero)) < 0)
-    return "IP_MULTICAST_LOOP";
 
-  if (setsockopt(s->fd, SOL_IP, IP_MULTICAST_TTL, &s->ttl, sizeof(s->ttl)) < 0)
-    return "IP_MULTICAST_TTL";
+#ifndef TCP_MD5SIG
 
-  /* This defines where should we send _outgoing_ multicasts */
-  fill_mreqn(&m, IPA_NONE, s->iface);
-  if (setsockopt(s->fd, SOL_IP, IP_MULTICAST_IF, &m, sizeof(m)) < 0)
-    return "IP_MULTICAST_IF";
+#define TCP_MD5SIG  14
+#define TCP_MD5SIG_MAXKEYLEN 80
 
-  return NULL;
-}
+struct tcp_md5sig {
+  struct  sockaddr_storage tcpm_addr;             /* address associated */
+  u16   __tcpm_pad1;                              /* zero */
+  u16   tcpm_keylen;                              /* key length */
+  u32   __tcpm_pad2;                              /* zero */
+  u8    tcpm_key[TCP_MD5SIG_MAXKEYLEN];           /* key (binary) */
+};
 
-static inline char *
-sysio_join_group(sock *s, ip_addr maddr)
-{
-  struct ip_mreqn m;
+#endif
 
-  /* And this one sets interface for _receiving_ multicasts from */
-  fill_mreqn(&m, maddr, s->iface);
-  if (setsockopt(s->fd, SOL_IP, IP_ADD_MEMBERSHIP, &m, sizeof(m)) < 0)
-    return "IP_ADD_MEMBERSHIP";
 
-  return NULL;
-}
+/* Linux does not care if sa_len is larger than needed */
+#define SA_LEN(x) sizeof(sockaddr)
 
-static inline char *
-sysio_leave_group(sock *s, ip_addr maddr)
-{
-  struct ip_mreqn m;
 
-  /* And this one sets interface for _receiving_ multicasts from */
-  fill_mreqn(&m, maddr, s->iface);
-  if (setsockopt(s->fd, SOL_IP, IP_DROP_MEMBERSHIP, &m, sizeof(m)) < 0)
-    return "IP_DROP_MEMBERSHIP";
+/*
+ *	Linux IPv4 multicast syscalls
+ */
 
-  return NULL;
-}
+#define INIT_MREQ4(maddr,ifa) \
+  { .imr_multiaddr = ipa_to_in4(maddr), .imr_ifindex = ifa->index }
 
-#endif
+static inline int
+sk_setup_multicast4(sock *s)
+{
+  struct ip_mreqn mr = { .imr_ifindex = s->iface->index };
+  int ttl = s->ttl;
+  int n = 0;
 
+  /* This defines where should we send _outgoing_ multicasts */
+  if (setsockopt(s->fd, SOL_IP, IP_MULTICAST_IF, &mr, sizeof(mr)) < 0)
+    ERR("IP_MULTICAST_IF");
 
-/* For the case that we have older libc headers */
-/* Copied from Linux kernel file include/linux/tcp.h */
+  if (setsockopt(s->fd, SOL_IP, IP_MULTICAST_TTL, &ttl, sizeof(ttl)) < 0)
+    ERR("IP_MULTICAST_TTL");
 
-#ifndef TCP_MD5SIG
+  if (setsockopt(s->fd, SOL_IP, IP_MULTICAST_LOOP, &n, sizeof(n)) < 0)
+    ERR("IP_MULTICAST_LOOP");
 
-#define TCP_MD5SIG  14
-#define TCP_MD5SIG_MAXKEYLEN 80
+  return 0;
+}
 
-#include <linux/types.h>
+static inline int
+sk_join_group4(sock *s, ip_addr maddr)
+{
+  struct ip_mreqn mr = INIT_MREQ4(maddr, s->iface);
 
-struct tcp_md5sig {
-  struct  sockaddr_storage tcpm_addr;             /* address associated */
-  __u16   __tcpm_pad1;                            /* zero */
-  __u16   tcpm_keylen;                            /* key length */
-  __u32   __tcpm_pad2;                            /* zero */
-  __u8    tcpm_key[TCP_MD5SIG_MAXKEYLEN];         /* key (binary) */
-};
+  if (setsockopt(s->fd, SOL_IP, IP_ADD_MEMBERSHIP, &mr, sizeof(mr)) < 0)
+    ERR("IP_ADD_MEMBERSHIP");
 
-#endif
+  return 0;
+}
 
-static int
-sk_set_md5_auth_int(sock *s, sockaddr *sa, char *passwd)
+static inline int
+sk_leave_group4(sock *s, ip_addr maddr)
 {
-  struct tcp_md5sig md5;
+  struct ip_mreqn mr = INIT_MREQ4(maddr, s->iface);
 
-  memset(&md5, 0, sizeof(md5));
-  memcpy(&md5.tcpm_addr, (struct sockaddr *) sa, sizeof(*sa));
+  if (setsockopt(s->fd, SOL_IP, IP_DROP_MEMBERSHIP, &mr, sizeof(mr)) < 0)
+    ERR("IP_DROP_MEMBERSHIP");
 
-  if (passwd)
-    {
-      int len = strlen(passwd);
-
-      if (len > TCP_MD5SIG_MAXKEYLEN)
-	{
-	  log(L_ERR "MD5 password too long");
-	  return -1;
-	}
-
-      md5.tcpm_keylen = len;
-      memcpy(&md5.tcpm_key, passwd, len);
-    }
-
-  int rv = setsockopt(s->fd, SOL_TCP, TCP_MD5SIG, &md5, sizeof(md5));
-
-  if (rv < 0) 
-    {
-      if (errno == ENOPROTOOPT)
-	log(L_ERR "Kernel does not support TCP MD5 signatures");
-      else
-	log(L_ERR "sk_set_md5_auth_int: setsockopt: %m");
-    }
-
-  return rv;
+  return 0;
 }
 
 
-#ifndef IPV6
+/*
+ *	Linux IPv4 packet control messages
+ */
 
-/* RX/TX packet info handling for IPv4 */
 /* Mostly similar to standardized IPv6 code */
 
-#define CMSG_RX_SPACE (CMSG_SPACE(sizeof(struct in_pktinfo)) + CMSG_SPACE(sizeof(int)))
-#define CMSG_TX_SPACE CMSG_SPACE(sizeof(struct in_pktinfo))
+#define CMSG4_SPACE_PKTINFO CMSG_SPACE(sizeof(struct in_pktinfo))
+#define CMSG4_SPACE_TTL CMSG_SPACE(sizeof(int))
 
-static char *
-sysio_register_cmsgs(sock *s)
+static inline int
+sk_request_cmsg4_pktinfo(sock *s)
 {
-  int ok = 1;
+  int y = 1;
 
-  if ((s->flags & SKF_LADDR_RX) &&
-      (setsockopt(s->fd, SOL_IP, IP_PKTINFO, &ok, sizeof(ok)) < 0))
-    return "IP_PKTINFO";
+  if (setsockopt(s->fd, SOL_IP, IP_PKTINFO, &y, sizeof(y)) < 0)
+    ERR("IP_PKTINFO");
 
-  if ((s->flags & SKF_TTL_RX) &&
-      (setsockopt(s->fd, SOL_IP, IP_RECVTTL, &ok, sizeof(ok)) < 0))
-    return "IP_RECVTTL";
-
-  return NULL;
+  return 0;
 }
 
-static void
-sysio_process_rx_cmsgs(sock *s, struct msghdr *msg)
+static inline int
+sk_request_cmsg4_ttl(sock *s)
 {
-  struct cmsghdr *cm;
-  struct in_pktinfo *pi = NULL;
-  int *ttl = NULL;
+  int y = 1;
 
-  for (cm = CMSG_FIRSTHDR(msg); cm != NULL; cm = CMSG_NXTHDR(msg, cm))
-  {
-    if (cm->cmsg_level == SOL_IP && cm->cmsg_type == IP_PKTINFO)
-      pi = (struct in_pktinfo *) CMSG_DATA(cm);
+  if (setsockopt(s->fd, SOL_IP, IP_RECVTTL, &y, sizeof(y)) < 0)
+    ERR("IP_RECVTTL");
 
-    if (cm->cmsg_level == SOL_IP && cm->cmsg_type == IP_TTL)
-      ttl = (int *) CMSG_DATA(cm);
-  }
+  return 0;
+}
 
-  if (s->flags & SKF_LADDR_RX)
+static inline void
+sk_process_cmsg4_pktinfo(sock *s, struct cmsghdr *cm)
+{
+  if (cm->cmsg_type == IP_PKTINFO)
   {
-    if (pi)
-    {
-      get_inaddr(&s->laddr, &pi->ipi_addr);
-      s->lifindex = pi->ipi_ifindex;
-    }
-    else
-    {
-      s->laddr = IPA_NONE;
-      s->lifindex = 0;
-    }
+    struct in_pktinfo *pi = (struct in_pktinfo *) CMSG_DATA(cm);
+    s->laddr = ipa_from_in4(pi->ipi_addr);
+    s->lifindex = pi->ipi_ifindex;
   }
+}
 
-  if (s->flags & SKF_TTL_RX)
-    s->ttl = ttl ? *ttl : -1;
-
-  return;
+static inline void
+sk_process_cmsg4_ttl(sock *s, struct cmsghdr *cm)
+{
+  if (cm->cmsg_type == IP_TTL)
+    s->rcv_ttl = * (int *) CMSG_DATA(cm);
 }
 
-static void
-sysio_prepare_tx_cmsgs(sock *s, struct msghdr *msg, void *cbuf, size_t cbuflen)
+static inline void
+sk_prepare_cmsgs4(sock *s, struct msghdr *msg, void *cbuf, size_t cbuflen)
 {
   struct cmsghdr *cm;
   struct in_pktinfo *pi;
@@ -246,78 +165,105 @@ sysio_prepare_tx_cmsgs(sock *s, struct msghdr *msg, void *cbuf, size_t cbuflen)
 
   pi = (struct in_pktinfo *) CMSG_DATA(cm);
   pi->ipi_ifindex = s->iface ? s->iface->index : 0;
-  set_inaddr(&pi->ipi_spec_dst, s->saddr);
-  set_inaddr(&pi->ipi_addr, IPA_NONE);
+  pi->ipi_spec_dst = ipa_to_in4(s->saddr);
+  pi->ipi_addr = ipa_to_in4(IPA_NONE);
 
   msg->msg_controllen = cm->cmsg_len;
 }
 
 
-#endif
+/*
+ *	Miscellaneous Linux socket syscalls
+ */
 
+int
+sk_set_md5_auth(sock *s, ip_addr a, struct iface *ifa, char *passwd)
+{
+  struct tcp_md5sig md5;
 
-#ifndef IP_MINTTL
-#define IP_MINTTL 21
-#endif
+  memset(&md5, 0, sizeof(md5));
+  sockaddr_fill((sockaddr *) &md5.tcpm_addr, s->af, a, ifa, 0);
 
-#ifndef IPV6_MINHOPCOUNT
-#define IPV6_MINHOPCOUNT 73
-#endif
+  if (passwd)
+  {
+    int len = strlen(passwd);
+
+    if (len > TCP_MD5SIG_MAXKEYLEN)
+      ERR_MSG("MD5 password too long");
 
+    md5.tcpm_keylen = len;
+    memcpy(&md5.tcpm_key, passwd, len);
+  }
+
+  if (setsockopt(s->fd, SOL_TCP, TCP_MD5SIG, &md5, sizeof(md5)) < 0)
+  {
+    if (errno == ENOPROTOOPT)
+      ERR_MSG("Kernel does not support TCP MD5 signatures");
+    else
+      ERR("TCP_MD5SIG");
+  }
 
-#ifndef IPV6
+  return 0;
+}
 
-static int
+static inline int
 sk_set_min_ttl4(sock *s, int ttl)
 {
   if (setsockopt(s->fd, SOL_IP, IP_MINTTL, &ttl, sizeof(ttl)) < 0)
   {
     if (errno == ENOPROTOOPT)
-      log(L_ERR "Kernel does not support IPv4 TTL security");
+      ERR_MSG("Kernel does not support IPv4 TTL security");
     else
-      log(L_ERR "sk_set_min_ttl4: setsockopt: %m");
-
-    return -1;
+      ERR("IP_MINTTL");
   }
 
   return 0;
 }
 
-#else
-
-static int
+static inline int
 sk_set_min_ttl6(sock *s, int ttl)
 {
   if (setsockopt(s->fd, SOL_IPV6, IPV6_MINHOPCOUNT, &ttl, sizeof(ttl)) < 0)
   {
     if (errno == ENOPROTOOPT)
-      log(L_ERR "Kernel does not support IPv6 TTL security");
+      ERR_MSG("Kernel does not support IPv6 TTL security");
     else
-      log(L_ERR "sk_set_min_ttl6: setsockopt: %m");
-
-    return -1;
+      ERR("IPV6_MINHOPCOUNT");
   }
 
   return 0;
 }
 
-#endif
+static inline int
+sk_disable_mtu_disc4(sock *s)
+{
+  int dont = IP_PMTUDISC_DONT;
 
+  if (setsockopt(s->fd, SOL_IP, IP_MTU_DISCOVER, &dont, sizeof(dont)) < 0)
+    ERR("IP_MTU_DISCOVER");
 
-#ifndef IPV6_TCLASS
-#define IPV6_TCLASS 67
-#endif
+  return 0;
+}
+
+static inline int
+sk_disable_mtu_disc6(sock *s)
+{
+  int dont = IPV6_PMTUDISC_DONT;
+
+  if (setsockopt(s->fd, SOL_IPV6, IPV6_MTU_DISCOVER, &dont, sizeof(dont)) < 0)
+    ERR("IPV6_MTU_DISCOVER");
+
+  return 0;
+}
 
 int sk_priority_control = 7;
 
-static int
+static inline int
 sk_set_priority(sock *s, int prio)
 {
   if (setsockopt(s->fd, SOL_SOCKET, SO_PRIORITY, &prio, sizeof(prio)) < 0)
-  {
-    log(L_WARN "sk_set_priority: setsockopt: %m");
-    return -1;
-  }
+    ERR("SO_PRIORITY");
 
   return 0;
 }
+
diff --git a/sysdep/unix/io.c b/sysdep/unix/io.c
index 428f24cc..5a0c07e5 100644
--- a/sysdep/unix/io.c
+++ b/sysdep/unix/io.c
@@ -22,6 +22,7 @@
 #include <unistd.h>
 #include <fcntl.h>
 #include <errno.h>
+#include <net/if.h>
 #include <netinet/in.h>
 #include <netinet/tcp.h>
 #include <netinet/udp.h>
@@ -470,6 +471,7 @@ tm_format_datetime(char *x, struct timeformat *fmt_spec, bird_clock_t t)
     strcpy(x, "<too-long>");
 }
 
+
 /**
  * DOC: Sockets
  *
@@ -496,234 +498,147 @@ tm_format_datetime(char *x, struct timeformat *fmt_spec, bird_clock_t t)
 #endif
 
 
-static list sock_list;
-static struct birdsock *current_sock;
-static struct birdsock *stored_sock;
-static int sock_recalc_fdsets_p;
+/*
+ *	Sockaddr helper functions
+ */
 
-static inline sock *
-sk_next(sock *s)
+static inline int sockaddr_length(int af)
+{ return (af == AF_INET) ? sizeof(struct sockaddr_in) : sizeof(struct sockaddr_in6); }
+
+static inline void
+sockaddr_fill4(struct sockaddr_in *sa, ip_addr a, struct iface *ifa, uint port)
 {
-  if (!s->n.next->next)
-    return NULL;
-  else
-    return SKIP_BACK(sock, n, s->n.next);
+  memset(sa, 0, sizeof(struct sockaddr_in));
+#ifdef HAVE_SIN_LEN
+  sa->sin_len = sizeof(struct sockaddr_in);
+#endif
+  sa->sin_family = AF_INET;
+  sa->sin_port = htons(port);
+  sa->sin_addr = ipa_to_in4(a);
 }
 
-static void
-sk_alloc_bufs(sock *s)
+static inline void
+sockaddr_fill6(struct sockaddr_in6 *sa, ip_addr a, struct iface *ifa, uint port)
 {
-  if (!s->rbuf && s->rbsize)
-    s->rbuf = s->rbuf_alloc = xmalloc(s->rbsize);
-  s->rpos = s->rbuf;
-  if (!s->tbuf && s->tbsize)
-    s->tbuf = s->tbuf_alloc = xmalloc(s->tbsize);
-  s->tpos = s->ttx = s->tbuf;
+  memset(sa, 0, sizeof(struct sockaddr_in6));
+#ifdef SIN6_LEN
+  sa->sin6_len = sizeof(struct sockaddr_in6);
+#endif
+  sa->sin6_family = AF_INET6;
+  sa->sin6_port = htons(port);
+  sa->sin6_flowinfo = 0;
+  sa->sin6_addr = ipa_to_in6(a);
+
+  if (ifa && ipa_is_link_local(a))
+    sa->sin6_scope_id = ifa->index;
 }
 
-static void
-sk_free_bufs(sock *s)
+void
+sockaddr_fill(sockaddr *sa, int af, ip_addr a, struct iface *ifa, uint port)
 {
-  if (s->rbuf_alloc)
-    {
-      xfree(s->rbuf_alloc);
-      s->rbuf = s->rbuf_alloc = NULL;
-    }
-  if (s->tbuf_alloc)
-    {
-      xfree(s->tbuf_alloc);
-      s->tbuf = s->tbuf_alloc = NULL;
-    }
+  if (af == AF_INET)
+    sockaddr_fill4((struct sockaddr_in *) sa, a, ifa, port);
+  else if (af == AF_INET6)
+    sockaddr_fill6((struct sockaddr_in6 *) sa, a, ifa, port);
+  else
+    bug("Unknown AF");
 }
 
-static void
-sk_free(resource *r)
+static inline void
+sockaddr_read4(struct sockaddr_in *sa, ip_addr *a, struct iface **ifa, uint *port)
 {
-  sock *s = (sock *) r;
-
-  sk_free_bufs(s);
-  if (s->fd >= 0)
-    {
-      close(s->fd);
-
-      /* FIXME: we should call sk_stop() for SKF_THREAD sockets */
-      if (s->flags & SKF_THREAD)
-	return;
-
-      if (s == current_sock)
-	current_sock = sk_next(s);
-      if (s == stored_sock)
-	stored_sock = sk_next(s);
-      rem_node(&s->n);
-      sock_recalc_fdsets_p = 1;
-    }
+  *port = ntohs(sa->sin_port);
+  *a = ipa_from_in4(sa->sin_addr);
 }
 
-void
-sk_set_rbsize(sock *s, uint val)
+static inline void
+sockaddr_read6(struct sockaddr_in6 *sa, ip_addr *a, struct iface **ifa, uint *port)
 {
-  ASSERT(s->rbuf_alloc == s->rbuf);
-
-  if (s->rbsize == val)
-    return;
+  *port = ntohs(sa->sin6_port);
+  *a = ipa_from_in6(sa->sin6_addr);
 
-  s->rbsize = val;
-  xfree(s->rbuf_alloc);
-  s->rbuf_alloc = xmalloc(val);
-  s->rpos = s->rbuf = s->rbuf_alloc;
+  if (ifa && ipa_is_link_local(*a))
+    *ifa = if_find_by_index(sa->sin6_scope_id);
 }
 
-void
-sk_set_tbsize(sock *s, uint val)
+int
+sockaddr_read(sockaddr *sa, int af, ip_addr *a, struct iface **ifa, uint *port)
 {
-  ASSERT(s->tbuf_alloc == s->tbuf);
+  if (sa->sa.sa_family != af)
+    goto fail;
 
-  if (s->tbsize == val)
-    return;
-
-  byte *old_tbuf = s->tbuf;
+  if (af == AF_INET)
+    sockaddr_read4((struct sockaddr_in *) sa, a, ifa, port);
+  else if (af == AF_INET6)
+    sockaddr_read6((struct sockaddr_in6 *) sa, a, ifa, port);
+  else
+    goto fail;
 
-  s->tbsize = val;
-  s->tbuf = s->tbuf_alloc = xrealloc(s->tbuf_alloc, val);
-  s->tpos = s->tbuf + (s->tpos - old_tbuf);
-  s->ttx  = s->tbuf + (s->ttx  - old_tbuf);
-}
+  return 0;
 
-void
-sk_set_tbuf(sock *s, void *tbuf)
-{
-  s->tbuf = tbuf ?: s->tbuf_alloc;
-  s->ttx = s->tpos = s->tbuf;
+ fail:
+  *a = IPA_NONE;
+  *port = 0;
+  return -1;
 }
 
-void
-sk_reallocate(sock *s)
-{
-  sk_free_bufs(s);
-  sk_alloc_bufs(s);
-}
 
-static void
-sk_dump(resource *r)
-{
-  sock *s = (sock *) r;
-  static char *sk_type_names[] = { "TCP<", "TCP>", "TCP", "UDP", "UDP/MC", "IP", "IP/MC", "MAGIC", "UNIX<", "UNIX", "DEL!" };
+/*
+ *	IPv6 multicast syscalls
+ */
 
-  debug("(%s, ud=%p, sa=%08x, sp=%d, da=%08x, dp=%d, tos=%d, ttl=%d, if=%s)\n",
-	sk_type_names[s->type],
-	s->data,
-	s->saddr,
-	s->sport,
-	s->daddr,
-	s->dport,
-	s->tos,
-	s->ttl,
-	s->iface ? s->iface->name : "none");
-}
+/* Fortunately standardized in RFC 3493 */
 
-static struct resclass sk_class = {
-  "Socket",
-  sizeof(sock),
-  sk_free,
-  sk_dump,
-  NULL,
-  NULL
-};
+#define INIT_MREQ6(maddr,ifa) \
+  { .ipv6mr_multiaddr = ipa_to_in6(maddr), .ipv6mr_interface = ifa->index }
 
-/**
- * sk_new - create a socket
- * @p: pool
- *
- * This function creates a new socket resource. If you want to use it,
- * you need to fill in all the required fields of the structure and
- * call sk_open() to do the actual opening of the socket.
- *
- * The real function name is sock_new(), sk_new() is a macro wrapper
- * to avoid collision with OpenSSL.
- */
-sock *
-sock_new(pool *p)
+static inline int
+sk_setup_multicast6(sock *s)
 {
-  sock *s = ralloc(p, &sk_class);
-  s->pool = p;
-  // s->saddr = s->daddr = IPA_NONE;
-  s->tos = s->priority = s->ttl = -1;
-  s->fd = -1;
-  return s;
-}
+  int index = s->iface->index;
+  int ttl = s->ttl;
+  int n = 0;
 
-static void
-sk_insert(sock *s)
-{
-  add_tail(&sock_list, &s->n);
-  sock_recalc_fdsets_p = 1;
-}
+  if (setsockopt(s->fd, SOL_IPV6, IPV6_MULTICAST_IF, &index, sizeof(index)) < 0)
+    ERR("IPV6_MULTICAST_IF");
 
-#ifdef IPV6
+  if (setsockopt(s->fd, SOL_IPV6, IPV6_MULTICAST_HOPS, &ttl, sizeof(ttl)) < 0)
+    ERR("IPV6_MULTICAST_HOPS");
 
-void
-fill_in_sockaddr(struct sockaddr_in6 *sa, ip_addr a, struct iface *ifa, unsigned port)
-{
-  memset(sa, 0, sizeof (struct sockaddr_in6));
-  sa->sin6_family = AF_INET6;
-  sa->sin6_port = htons(port);
-  sa->sin6_flowinfo = 0;
-#ifdef HAVE_SIN_LEN
-  sa->sin6_len = sizeof(struct sockaddr_in6);
-#endif
-  set_inaddr(&sa->sin6_addr, a);
+  if (setsockopt(s->fd, SOL_IPV6, IPV6_MULTICAST_LOOP, &n, sizeof(n)) < 0)
+    ERR("IPV6_MULTICAST_LOOP");
 
-  if (ifa && ipa_has_link_scope(a))
-    sa->sin6_scope_id = ifa->index;
+  return 0;
 }
 
-void
-get_sockaddr(struct sockaddr_in6 *sa, ip_addr *a, struct iface **ifa, unsigned *port, int check)
+static inline int
+sk_join_group6(sock *s, ip_addr maddr)
 {
-  if (check && sa->sin6_family != AF_INET6)
-    bug("get_sockaddr called for wrong address family (%d)", sa->sin6_family);
-  if (port)
-    *port = ntohs(sa->sin6_port);
-  memcpy(a, &sa->sin6_addr, sizeof(*a));
-  ipa_ntoh(*a);
+  struct ipv6_mreq mr = INIT_MREQ6(maddr, s->iface);
 
-  if (ifa && ipa_has_link_scope(*a))
-    *ifa = if_find_by_index(sa->sin6_scope_id);
-}
+  if (setsockopt(s->fd, SOL_IPV6, IPV6_JOIN_GROUP, &mr, sizeof(mr)) < 0)
+    ERR("IPV6_JOIN_GROUP");
 
-#else
-
-void
-fill_in_sockaddr(struct sockaddr_in *sa, ip_addr a, struct iface *ifa, unsigned port)
-{
-  memset (sa, 0, sizeof (struct sockaddr_in));
-  sa->sin_family = AF_INET;
-  sa->sin_port = htons(port);
-#ifdef HAVE_SIN_LEN
-  sa->sin_len = sizeof(struct sockaddr_in);
-#endif
-  set_inaddr(&sa->sin_addr, a);
+  return 0;
 }
 
-void
-get_sockaddr(struct sockaddr_in *sa, ip_addr *a, struct iface **ifa, unsigned *port, int check)
+static inline int
+sk_leave_group6(sock *s, ip_addr maddr)
 {
-  if (check && sa->sin_family != AF_INET)
-    bug("get_sockaddr called for wrong address family (%d)", sa->sin_family);
-  if (port)
-    *port = ntohs(sa->sin_port);
-  memcpy(a, &sa->sin_addr.s_addr, sizeof(*a));
-  ipa_ntoh(*a);
-}
+  struct ipv6_mreq mr = INIT_MREQ6(maddr, s->iface);
 
-#endif
+  if (setsockopt(s->fd, SOL_IPV6, IPV6_LEAVE_GROUP, &mr, sizeof(mr)) < 0)
+    ERR("IPV6_LEAVE_GROUP");
+
+  return 0;
+}
 
 
-#ifdef IPV6
+/*
+ *	IPv6 packet control messages
+ */
 
-/* PKTINFO handling is also standardized in IPv6 */
-#define CMSG_RX_SPACE (CMSG_SPACE(sizeof(struct in6_pktinfo)) + CMSG_SPACE(sizeof(int)))
-#define CMSG_TX_SPACE CMSG_SPACE(sizeof(struct in6_pktinfo))
+/* Also standardized, in RFC 3542 */
 
 /*
  * RFC 2292 uses IPV6_PKTINFO for both the socket option and the cmsg
@@ -741,60 +656,52 @@ get_sockaddr(struct sockaddr_in *sa, ip_addr *a, struct iface **ifa, unsigned *p
 #define IPV6_RECVHOPLIMIT IPV6_HOPLIMIT
 #endif
 
-static char *
-sysio_register_cmsgs(sock *s)
-{
-  int ok = 1;
 
-  if ((s->flags & SKF_LADDR_RX) &&
-      (setsockopt(s->fd, SOL_IPV6, IPV6_RECVPKTINFO, &ok, sizeof(ok)) < 0))
-    return "IPV6_RECVPKTINFO";
+#define CMSG6_SPACE_PKTINFO CMSG_SPACE(sizeof(struct in6_pktinfo))
+#define CMSG6_SPACE_TTL CMSG_SPACE(sizeof(int))
+
+static inline int
+sk_request_cmsg6_pktinfo(sock *s)
+{
+  int y = 1;
 
-  if ((s->flags & SKF_TTL_RX) &&
-      (setsockopt(s->fd, SOL_IPV6, IPV6_RECVHOPLIMIT, &ok, sizeof(ok)) < 0))
-    return "IPV6_RECVHOPLIMIT";
+  if (setsockopt(s->fd, SOL_IPV6, IPV6_RECVPKTINFO, &y, sizeof(y)) < 0)
+    ERR("IPV6_RECVPKTINFO");
 
-  return NULL;
+  return 0;
 }
 
-static void
-sysio_process_rx_cmsgs(sock *s, struct msghdr *msg)
+static inline int
+sk_request_cmsg6_ttl(sock *s)
 {
-  struct cmsghdr *cm;
-  struct in6_pktinfo *pi = NULL;
-  int *hlim = NULL;
+  int y = 1;
 
-  for (cm = CMSG_FIRSTHDR(msg); cm != NULL; cm = CMSG_NXTHDR(msg, cm))
-  {
-    if (cm->cmsg_level == SOL_IPV6 && cm->cmsg_type == IPV6_PKTINFO)
-      pi = (struct in6_pktinfo *) CMSG_DATA(cm);
+  if (setsockopt(s->fd, SOL_IPV6, IPV6_RECVHOPLIMIT, &y, sizeof(y)) < 0)
+    ERR("IPV6_RECVHOPLIMIT");
 
-    if (cm->cmsg_level == SOL_IPV6 && cm->cmsg_type == IPV6_HOPLIMIT)
-      hlim = (int *) CMSG_DATA(cm);
-  }
+  return 0;
+}
 
-  if (s->flags & SKF_LADDR_RX)
+static inline void
+sk_process_cmsg6_pktinfo(sock *s, struct cmsghdr *cm)
+{
+  if (cm->cmsg_type == IPV6_PKTINFO)
   {
-    if (pi)
-    {
-      get_inaddr(&s->laddr, &pi->ipi6_addr);
-      s->lifindex = pi->ipi6_ifindex;
-    }
-    else
-    {
-      s->laddr = IPA_NONE;
-      s->lifindex = 0;
-    }
+    struct in6_pktinfo *pi = (struct in6_pktinfo *) CMSG_DATA(cm);
+    s->laddr = ipa_from_in6(pi->ipi6_addr);
+    s->lifindex = pi->ipi6_ifindex;
   }
+}
 
-  if (s->flags & SKF_TTL_RX)
-    s->ttl = hlim ? *hlim : -1;
-
-  return;
+static inline void
+sk_process_cmsg6_ttl(sock *s, struct cmsghdr *cm)
+{
+  if (cm->cmsg_type == IPV6_HOPLIMIT)
+    s->rcv_ttl = * (int *) CMSG_DATA(cm);
 }
 
-static void
-sysio_prepare_tx_cmsgs(sock *s, struct msghdr *msg, void *cbuf, size_t cbuflen)
+static inline void
+sk_prepare_cmsgs6(sock *s, struct msghdr *msg, void *cbuf, size_t cbuflen)
 {
   struct cmsghdr *cm;
   struct in6_pktinfo *pi;
@@ -809,104 +716,147 @@ sysio_prepare_tx_cmsgs(sock *s, struct msghdr *msg, void *cbuf, size_t cbuflen)
 
   pi = (struct in6_pktinfo *) CMSG_DATA(cm);
   pi->ipi6_ifindex = s->iface ? s->iface->index : 0;
-  set_inaddr(&pi->ipi6_addr, s->saddr);
+  pi->ipi6_addr = ipa_to_in6(s->saddr);
 
   msg->msg_controllen = cm->cmsg_len;
 }
 
-#endif
 
-static char *
-sk_set_ttl_int(sock *s)
+/*
+ *	Miscellaneous socket syscalls
+ */
+
+static inline int
+sk_set_ttl4(sock *s, int ttl)
 {
-#ifdef IPV6
-  if (setsockopt(s->fd, SOL_IPV6, IPV6_UNICAST_HOPS, &s->ttl, sizeof(s->ttl)) < 0)
-    return "IPV6_UNICAST_HOPS";
-#else
-  if (setsockopt(s->fd, SOL_IP, IP_TTL, &s->ttl, sizeof(s->ttl)) < 0)
-    return "IP_TTL";
-#endif
-  return NULL;
+  if (setsockopt(s->fd, SOL_IP, IP_TTL, &ttl, sizeof(ttl)) < 0)
+    ERR("IP_TTL");
+
+  return 0;
 }
 
-#define ERR(x) do { err = x; goto bad; } while(0)
-#define WARN(x) log(L_WARN "sk_setup: %s: %m", x)
+static inline int
+sk_set_ttl6(sock *s, int ttl)
+{
+  if (setsockopt(s->fd, SOL_IPV6, IPV6_UNICAST_HOPS, &ttl, sizeof(ttl)) < 0)
+    ERR("IPV6_UNICAST_HOPS");
 
-static char *
-sk_setup(sock *s)
+  return 0;
+}
+
+static inline int
+sk_set_tos4(sock *s, int tos)
 {
-  int one = 1;
-  int fd = s->fd;
-  char *err = NULL;
+  if (setsockopt(s->fd, SOL_IP, IP_TOS, &tos, sizeof(tos)) < 0)
+    ERR("IP_TOS");
 
-  if (fcntl(fd, F_SETFL, O_NONBLOCK) < 0)
-    ERR("fcntl(O_NONBLOCK)");
-  if (s->type == SK_UNIX)
-    return NULL;
+  return 0;
+}
 
-  if (ipa_nonzero(s->saddr) && !(s->flags & SKF_BIND))
-    s->flags |= SKF_PKTINFO;
+static inline int
+sk_set_tos6(sock *s, int tos)
+{
+  if (setsockopt(s->fd, SOL_IPV6, IPV6_TCLASS, &tos, sizeof(tos)) < 0)
+    ERR("IPV6_TCLASS");
 
-#ifdef CONFIG_USE_HDRINCL
-  if ((s->type == SK_IP) && (s->flags & SKF_PKTINFO))
-  {
-    s->flags &= ~SKF_PKTINFO;
-    s->flags |= SKF_HDRINCL;
-    if (setsockopt(fd, SOL_IP, IP_HDRINCL, &one, sizeof(one)) < 0)
-      ERR("IP_HDRINCL");
-  }
-#endif
+  return 0;
+}
 
-  if (s->iface)
-  {
-#ifdef SO_BINDTODEVICE
-    struct ifreq ifr;
-    strcpy(ifr.ifr_name, s->iface->name);
-    if (setsockopt(s->fd, SOL_SOCKET, SO_BINDTODEVICE, &ifr, sizeof(ifr)) < 0)
-      ERR("SO_BINDTODEVICE");
-#endif
 
-#ifdef CONFIG_UNIX_DONTROUTE
-    if (setsockopt(s->fd, SOL_SOCKET, SO_DONTROUTE, &one, sizeof(one)) < 0)
-      ERR("SO_DONTROUTE");
-#endif
-  }
+/*
+ *	Public socket functions
+ */
 
-  if ((s->ttl >= 0) && (err = sk_set_ttl_int(s)))
-    goto bad;
+/**
+ * sk_setup_multicast - enable multicast for given socket
+ * @s: socket
+ *
+ * Prepare transmission of multicast packets for given datagram socket.
+ * The socket must have defined @iface.
+ *
+ * Result: 0 for success, -1 for an error.
+ */
 
-  if (err = sysio_register_cmsgs(s))
-    goto bad;
+int
+sk_setup_multicast(sock *s)
+{
+  ASSERT(s->iface);
 
+  if (sk_is_ipv4(s))
+    return sk_setup_multicast4(s);
+  else
+    return sk_setup_multicast6(s);
+}
 
-#ifdef IPV6
-  if ((s->tos >= 0) && setsockopt(fd, SOL_IPV6, IPV6_TCLASS, &s->tos, sizeof(s->tos)) < 0)
-    WARN("IPV6_TCLASS");
-#else
-  if ((s->tos >= 0) && setsockopt(fd, SOL_IP, IP_TOS, &s->tos, sizeof(s->tos)) < 0)
-    WARN("IP_TOS");
-#endif
+/**
+ * sk_join_group - join multicast group for given socket
+ * @s: socket
+ * @maddr: multicast address
+ *
+ * Join multicast group for given datagram socket and associated interface.
+ * The socket must have defined @iface.
+ *
+ * Result: 0 for success, -1 for an error.
+ */
 
-  if (s->priority >= 0)
-    sk_set_priority(s, s->priority);
+int
+sk_join_group(sock *s, ip_addr maddr)
+{
+  if (sk_is_ipv4(s))
+    return sk_join_group4(s, maddr);
+  else
+    return sk_join_group6(s, maddr);
+}
 
-#ifdef IPV6
-  if ((s->flags & SKF_V6ONLY) && setsockopt(fd, SOL_IPV6, IPV6_V6ONLY, &one, sizeof(one)) < 0)
-    WARN("IPV6_V6ONLY");
-#endif
+/**
+ * sk_leave_group - leave multicast group for given socket
+ * @s: socket
+ * @maddr: multicast address
+ *
+ * Leave multicast group for given datagram socket and associated interface.
+ * The socket must have defined @iface.
+ *
+ * Result: 0 for success, -1 for an error.
+ */
+
+int
+sk_leave_group(sock *s, ip_addr maddr)
+{
+  if (sk_is_ipv4(s))
+    return sk_leave_group4(s, maddr);
+  else
+    return sk_leave_group6(s, maddr);
+}
+
+/**
+ * sk_setup_broadcast - enable broadcast for given socket
+ * @s: socket
+ *
+ * Allow reception and transmission of broadcast packets for given datagram
+ * socket. The socket must have defined @iface. For transmission, packets should
+ * be send to @brd address of @iface.
+ *
+ * Result: 0 for success, -1 for an error.
+ */
+
+int
+sk_setup_broadcast(sock *s)
+{
+  int y = 1;
+
+  if (setsockopt(s->fd, SOL_SOCKET, SO_BROADCAST, &y, sizeof(y)) < 0)
+    ERR("SO_BROADCAST");
 
-bad:
-  return err;
+  return 0;
 }
 
 /**
- * sk_set_ttl - set transmit TTL for given socket.
+ * sk_set_ttl - set transmit TTL for given socket
  * @s: socket
  * @ttl: TTL value
  *
- * Set TTL for already opened connections when TTL was not set before.
- * Useful for accepted connections when different ones should have 
- * different TTL.
+ * Set TTL for already opened connections when TTL was not set before. Useful
+ * for accepted connections when different ones should have different TTL.
  *
  * Result: 0 for success, -1 for an error.
  */
@@ -914,21 +864,21 @@ bad:
 int
 sk_set_ttl(sock *s, int ttl)
 {
-  char *err;
-
   s->ttl = ttl;
-  if (err = sk_set_ttl_int(s))
-    log(L_ERR "sk_set_ttl: %s: %m", err);
 
-  return (err ? -1 : 0);
+  if (sk_is_ipv4(s))
+    return sk_set_ttl4(s, ttl);
+  else
+    return sk_set_ttl6(s, ttl);
 }
 
 /**
- * sk_set_min_ttl - set minimal accepted TTL for given socket.
+ * sk_set_min_ttl - set minimal accepted TTL for given socket
  * @s: socket
  * @ttl: TTL value
  *
- * Can be used in TTL security implementation
+ * Set minimal accepted TTL for given socket. Can be used for TTL security.
+ * implementations.
  *
  * Result: 0 for success, -1 for an error.
  */
@@ -936,28 +886,24 @@ sk_set_ttl(sock *s, int ttl)
 int
 sk_set_min_ttl(sock *s, int ttl)
 {
-  int err;
-#ifdef IPV6
-  err = sk_set_min_ttl6(s, ttl);
-#else
-  err = sk_set_min_ttl4(s, ttl);
-#endif
-
-  return err;
+  if (sk_is_ipv4(s))
+    return sk_set_min_ttl4(s, ttl);
+  else
+    return sk_set_min_ttl6(s, ttl);
 }
 
+#if 0
 /**
- * sk_set_md5_auth - add / remove MD5 security association for given socket.
+ * sk_set_md5_auth - add / remove MD5 security association for given socket
  * @s: socket
  * @a: IP address of the other side
  * @ifa: Interface for link-local IP address
  * @passwd: password used for MD5 authentication
  *
- * In TCP MD5 handling code in kernel, there is a set of pairs
- * (address, password) used to choose password according to
- * address of the other side. This function is useful for
- * listening socket, for active sockets it is enough to set
- * s->password field.
+ * In TCP MD5 handling code in kernel, there is a set of pairs (address,
+ * password) used to choose password according to address of the other side.
+ * This function is useful for listening socket, for active sockets it is enough
+ * to set s->password field.
  *
  * When called with passwd != NULL, the new pair is added,
  * When called with passwd == NULL, the existing pair is removed.
@@ -967,41 +913,33 @@ sk_set_min_ttl(sock *s, int ttl)
 
 int
 sk_set_md5_auth(sock *s, ip_addr a, struct iface *ifa, char *passwd)
-{
-  sockaddr sa;
-  fill_in_sockaddr(&sa, a, ifa, 0);
-  return sk_set_md5_auth_int(s, &sa, passwd);
-}
-
-int
-sk_set_broadcast(sock *s, int enable)
-{
-  if (setsockopt(s->fd, SOL_SOCKET, SO_BROADCAST, &enable, sizeof(enable)) < 0)
-    {
-      log(L_ERR "sk_set_broadcast: SO_BROADCAST: %m");
-      return -1;
-    }
-
-  return 0;
-}
-
+{ DUMMY; }
+#endif
 
-#ifdef IPV6
+/**
+ * sk_set_ipv6_checksum - specify IPv6 checksum offset for given socket
+ * @s: socket
+ * @offset: offset
+ *
+ * Specify IPv6 checksum field offset for given raw IPv6 socket. After that, the
+ * kernel will automatically fill it for outgoing packets and check it for
+ * incoming packets. Should not be used on ICMPv6 sockets, where the position is
+ * known to the kernel.
+ *
+ * Result: 0 for success, -1 for an error.
+ */
 
 int
 sk_set_ipv6_checksum(sock *s, int offset)
 {
   if (setsockopt(s->fd, SOL_IPV6, IPV6_CHECKSUM, &offset, sizeof(offset)) < 0)
-    {
-      log(L_ERR "sk_set_ipv6_checksum: IPV6_CHECKSUM: %m");
-      return -1;
-    }
+    ERR("IPV6_CHECKSUM");
 
   return 0;
 }
 
 int
-sk_set_icmp_filter(sock *s, int p1, int p2)
+sk_set_icmp6_filter(sock *s, int p1, int p2)
 {
   /* a bit of lame interface, but it is here only for Radv */
   struct icmp6_filter f;
@@ -1011,132 +949,291 @@ sk_set_icmp_filter(sock *s, int p1, int p2)
   ICMP6_FILTER_SETPASS(p2, &f);
 
   if (setsockopt(s->fd, SOL_ICMPV6, ICMP6_FILTER, &f, sizeof(f)) < 0)
-    {
-      log(L_ERR "sk_setup_icmp_filter: ICMP6_FILTER: %m");
-      return -1;
-    }
+    ERR("ICMP6_FILTER");
 
   return 0;
 }
 
-int
-sk_setup_multicast(sock *s)
+void
+sk_log_error(sock *s, const char *p)
 {
-  char *err;
-  int zero = 0;
-  int index;
+  log(L_ERR "%s: Socket error: %s%#m", p, s->err);
+}
 
-  ASSERT(s->iface);
 
-  index = s->iface->index;
-  if (setsockopt(s->fd, SOL_IPV6, IPV6_MULTICAST_HOPS, &s->ttl, sizeof(s->ttl)) < 0)
-    ERR("IPV6_MULTICAST_HOPS");
-  if (setsockopt(s->fd, SOL_IPV6, IPV6_MULTICAST_LOOP, &zero, sizeof(zero)) < 0)
-    ERR("IPV6_MULTICAST_LOOP");
-  if (setsockopt(s->fd, SOL_IPV6, IPV6_MULTICAST_IF, &index, sizeof(index)) < 0)
-    ERR("IPV6_MULTICAST_IF");
+/*
+ *	Actual struct birdsock code
+ */
 
-  return 0;
+static list sock_list;
+static struct birdsock *current_sock;
+static struct birdsock *stored_sock;
+static int sock_recalc_fdsets_p;
 
-bad:
-  log(L_ERR "sk_setup_multicast: %s: %m", err);
-  return -1;
+static inline sock *
+sk_next(sock *s)
+{
+  if (!s->n.next->next)
+    return NULL;
+  else
+    return SKIP_BACK(sock, n, s->n.next);
 }
 
-#ifdef CONFIG_IPV6_GLIBC_20
-#define ipv6mr_interface ipv6mr_ifindex
-#endif
-
-int
-sk_join_group(sock *s, ip_addr maddr)
+static void
+sk_alloc_bufs(sock *s)
 {
-  struct ipv6_mreq mreq;
+  if (!s->rbuf && s->rbsize)
+    s->rbuf = s->rbuf_alloc = xmalloc(s->rbsize);
+  s->rpos = s->rbuf;
+  if (!s->tbuf && s->tbsize)
+    s->tbuf = s->tbuf_alloc = xmalloc(s->tbsize);
+  s->tpos = s->ttx = s->tbuf;
+}
 
-  set_inaddr(&mreq.ipv6mr_multiaddr, maddr);
-  mreq.ipv6mr_interface = s->iface->index;
+static void
+sk_free_bufs(sock *s)
+{
+  if (s->rbuf_alloc)
+  {
+    xfree(s->rbuf_alloc);
+    s->rbuf = s->rbuf_alloc = NULL;
+  }
+  if (s->tbuf_alloc)
+  {
+    xfree(s->tbuf_alloc);
+    s->tbuf = s->tbuf_alloc = NULL;
+  }
+}
 
-  if (setsockopt(s->fd, SOL_IPV6, IPV6_JOIN_GROUP, &mreq, sizeof(mreq)) < 0)
-    {
-      log(L_ERR "sk_join_group: IPV6_JOIN_GROUP: %m");
-      return -1;
-    }
+static void
+sk_free(resource *r)
+{
+  sock *s = (sock *) r;
 
-  return 0;
+  sk_free_bufs(s);
+  if (s->fd >= 0)
+  {
+    close(s->fd);
+
+    /* FIXME: we should call sk_stop() for SKF_THREAD sockets */
+    if (s->flags & SKF_THREAD)
+      return;
+
+    if (s == current_sock)
+      current_sock = sk_next(s);
+    if (s == stored_sock)
+      stored_sock = sk_next(s);
+    rem_node(&s->n);
+    sock_recalc_fdsets_p = 1;
+  }
 }
 
-int
-sk_leave_group(sock *s, ip_addr maddr)
+void
+sk_set_rbsize(sock *s, uint val)
 {
-  struct ipv6_mreq mreq;
-	
-  set_inaddr(&mreq.ipv6mr_multiaddr, maddr);
-  mreq.ipv6mr_interface = s->iface->index;
+  ASSERT(s->rbuf_alloc == s->rbuf);
 
-  if (setsockopt(s->fd, SOL_IPV6, IPV6_LEAVE_GROUP, &mreq, sizeof(mreq)) < 0)
-    {
-      log(L_ERR "sk_leave_group: IPV6_LEAVE_GROUP: %m");
-      return -1;
-    }
+  if (s->rbsize == val)
+    return;
 
-  return 0;
+  s->rbsize = val;
+  xfree(s->rbuf_alloc);
+  s->rbuf_alloc = xmalloc(val);
+  s->rpos = s->rbuf = s->rbuf_alloc;
 }
 
-#else /* IPV4 */
-
-int
-sk_setup_multicast(sock *s)
+void
+sk_set_tbsize(sock *s, uint val)
 {
-  char *err;
+  ASSERT(s->tbuf_alloc == s->tbuf);
 
-  ASSERT(s->iface);
+  if (s->tbsize == val)
+    return;
 
-  if (err = sysio_setup_multicast(s))
-    {
-      log(L_ERR "sk_setup_multicast: %s: %m", err);
-      return -1;
-    }
+  byte *old_tbuf = s->tbuf;
 
-  return 0;
+  s->tbsize = val;
+  s->tbuf = s->tbuf_alloc = xrealloc(s->tbuf_alloc, val);
+  s->tpos = s->tbuf + (s->tpos - old_tbuf);
+  s->ttx  = s->tbuf + (s->ttx  - old_tbuf);
 }
 
-int
-sk_join_group(sock *s, ip_addr maddr)
+void
+sk_set_tbuf(sock *s, void *tbuf)
 {
- char *err;
+  s->tbuf = tbuf ?: s->tbuf_alloc;
+  s->ttx = s->tpos = s->tbuf;
+}
 
- if (err = sysio_join_group(s, maddr))
-    {
-      log(L_ERR "sk_join_group: %s: %m", err);
-      return -1;
-    }
+void
+sk_reallocate(sock *s)
+{
+  sk_free_bufs(s);
+  sk_alloc_bufs(s);
+}
 
-  return 0;
+static void
+sk_dump(resource *r)
+{
+  sock *s = (sock *) r;
+  static char *sk_type_names[] = { "TCP<", "TCP>", "TCP", "UDP", NULL, "IP", NULL, "MAGIC", "UNIX<", "UNIX", "DEL!" };
+
+  debug("(%s, ud=%p, sa=%08x, sp=%d, da=%08x, dp=%d, tos=%d, ttl=%d, if=%s)\n",
+	sk_type_names[s->type],
+	s->data,
+	s->saddr,
+	s->sport,
+	s->daddr,
+	s->dport,
+	s->tos,
+	s->ttl,
+	s->iface ? s->iface->name : "none");
 }
 
-int
-sk_leave_group(sock *s, ip_addr maddr)
+static struct resclass sk_class = {
+  "Socket",
+  sizeof(sock),
+  sk_free,
+  sk_dump,
+  NULL,
+  NULL
+};
+
+/**
+ * sk_new - create a socket
+ * @p: pool
+ *
+ * This function creates a new socket resource. If you want to use it,
+ * you need to fill in all the required fields of the structure and
+ * call sk_open() to do the actual opening of the socket.
+ *
+ * The real function name is sock_new(), sk_new() is a macro wrapper
+ * to avoid collision with OpenSSL.
+ */
+sock *
+sock_new(pool *p)
+{
+  sock *s = ralloc(p, &sk_class);
+  s->pool = p;
+  // s->saddr = s->daddr = IPA_NONE;
+  s->tos = s->priority = s->ttl = -1;
+  s->fd = -1;
+  return s;
+}
+
+static int
+sk_setup(sock *s)
 {
- char *err;
+  int y = 1;
+  int fd = s->fd;
 
- if (err = sysio_leave_group(s, maddr))
-    {
-      log(L_ERR "sk_leave_group: %s: %m", err);
+  if (fcntl(fd, F_SETFL, O_NONBLOCK) < 0)
+    ERR("O_NONBLOCK");
+
+  if (!s->af)
+    return 0;
+
+  if (ipa_nonzero(s->saddr) && !(s->flags & SKF_BIND))
+    s->flags |= SKF_PKTINFO;
+
+#ifdef CONFIG_USE_HDRINCL
+  if (sk_is_ipv4(s) && (s->type == SK_IP) && (s->flags & SKF_PKTINFO))
+  {
+    s->flags &= ~SKF_PKTINFO;
+    s->flags |= SKF_HDRINCL;
+    if (setsockopt(fd, SOL_IP, IP_HDRINCL, &y, sizeof(y)) < 0)
+      ERR("IP_HDRINCL");
+  }
+#endif
+
+  if (s->iface)
+  {
+#ifdef SO_BINDTODEVICE
+    struct ifreq ifr;
+    strcpy(ifr.ifr_name, s->iface->name);
+    if (setsockopt(s->fd, SOL_SOCKET, SO_BINDTODEVICE, &ifr, sizeof(ifr)) < 0)
+      ERR("SO_BINDTODEVICE");
+#endif
+
+#ifdef CONFIG_UNIX_DONTROUTE
+    if (setsockopt(s->fd, SOL_SOCKET, SO_DONTROUTE, &y, sizeof(y)) < 0)
+      ERR("SO_DONTROUTE");
+#endif
+  }
+
+  if (s->priority >= 0)
+    if (sk_set_priority(s, s->priority) < 0)
       return -1;
-    }
+
+  if (sk_is_ipv4(s))
+  {
+    if (s->flags & SKF_LADDR_RX)
+      if (sk_request_cmsg4_pktinfo(s) < 0)
+	return -1;
+
+    if (s->flags & SKF_TTL_RX)
+      if (sk_request_cmsg4_ttl(s) < 0)
+	return -1;
+
+    if ((s->type == SK_UDP) || (s->type == SK_IP))
+      if (sk_disable_mtu_disc4(s) < 0)
+	return -1;
+
+    if (s->ttl >= 0)
+      if (sk_set_ttl4(s, s->ttl) < 0)
+	return -1;
+
+    if (s->tos >= 0)
+      if (sk_set_tos4(s, s->tos) < 0)
+	return -1;
+  }
+
+  if (sk_is_ipv6(s))
+  {
+    if (s->flags & SKF_V6ONLY)
+      if (setsockopt(fd, SOL_IPV6, IPV6_V6ONLY, &y, sizeof(y)) < 0)
+	ERR("IPV6_V6ONLY");
+
+    if (s->flags & SKF_LADDR_RX)
+      if (sk_request_cmsg6_pktinfo(s) < 0)
+	return -1;
+
+    if (s->flags & SKF_TTL_RX)
+      if (sk_request_cmsg6_ttl(s) < 0)
+	return -1;
+
+    if ((s->type == SK_UDP) || (s->type == SK_IP))
+      if (sk_disable_mtu_disc6(s) < 0)
+	return -1;
+
+    if (s->ttl >= 0)
+      if (sk_set_ttl6(s, s->ttl) < 0)
+	return -1;
+
+    if (s->tos >= 0)
+      if (sk_set_tos6(s, s->tos) < 0)
+	return -1;
+  }
 
   return 0;
 }
 
-#endif 
-
+static void
+sk_insert(sock *s)
+{
+  add_tail(&sock_list, &s->n);
+  sock_recalc_fdsets_p = 1;
+}
 
 static void
 sk_tcp_connected(sock *s)
 {
-  sockaddr lsa;
-  int lsa_len = sizeof(lsa);
-  if (getsockname(s->fd, (struct sockaddr *) &lsa, &lsa_len) == 0)
-    get_sockaddr(&lsa, &s->saddr, &s->iface, &s->sport, 1);
+  sockaddr sa;
+  int sa_len = sizeof(sa);
+
+  if ((getsockname(s->fd, &sa.sa, &sa_len) < 0) ||
+      (sockaddr_read(&sa, s->af, &s->saddr, &s->iface, &s->sport) < 0))
+    log(L_WARN "SOCK: Cannot get local IP address for TCP>");
 
   s->type = SK_TCP;
   sk_alloc_bufs(s);
@@ -1144,44 +1241,55 @@ sk_tcp_connected(sock *s)
 }
 
 static int
-sk_passive_connected(sock *s, struct sockaddr *sa, int al, int type)
+sk_passive_connected(sock *s, int type)
 {
-  int fd = accept(s->fd, sa, &al);
-  if (fd >= 0)
-    {
-      sock *t = sk_new(s->pool);
-      char *err;
-      t->type = type;
-      t->fd = fd;
-      t->ttl = s->ttl;
-      t->tos = s->tos;
-      t->rbsize = s->rbsize;
-      t->tbsize = s->tbsize;
-      if (type == SK_TCP)
-	{
-	  sockaddr lsa;
-	  int lsa_len = sizeof(lsa);
-	  if (getsockname(fd, (struct sockaddr *) &lsa, &lsa_len) == 0)
-	    get_sockaddr(&lsa, &t->saddr, &t->iface, &t->sport, 1);
+  sockaddr loc_sa, rem_sa;
+  int loc_sa_len = sizeof(loc_sa);
+  int rem_sa_len = sizeof(rem_sa);
 
-	  get_sockaddr((sockaddr *) sa, &t->daddr, &t->iface, &t->dport, 1);
-	}
-      sk_insert(t);
-      if (err = sk_setup(t))
-	{
-	  log(L_ERR "Incoming connection: %s: %m", err);
-	  rfree(t);
-	  return 1;
-	}
-      sk_alloc_bufs(t);
-      s->rx_hook(t, 0);
-      return 1;
-    }
-  else if (errno != EINTR && errno != EAGAIN)
-    {
+  int fd = accept(s->fd, ((type == SK_TCP) ? &rem_sa.sa : NULL), &rem_sa_len);
+  if (fd < 0)
+  {
+    if ((errno != EINTR) && (errno != EAGAIN))
       s->err_hook(s, errno);
-    }
-  return 0;
+    return 0;
+  }
+
+  sock *t = sk_new(s->pool);
+  t->type = type;
+  t->fd = fd;
+  t->af = s->af;
+  t->ttl = s->ttl;
+  t->tos = s->tos;
+  t->rbsize = s->rbsize;
+  t->tbsize = s->tbsize;
+
+  if (type == SK_TCP)
+  {
+    if ((getsockname(fd, &loc_sa.sa, &loc_sa_len) < 0) ||
+	(sockaddr_read(&loc_sa, s->af, &t->saddr, &t->iface, &t->sport) < 0))
+      log(L_WARN "SOCK: Cannot get local IP address for TCP<");
+
+    if (sockaddr_read(&rem_sa, s->af, &t->daddr, &t->iface, &t->dport) < 0)
+      log(L_WARN "SOCK: Cannot get remote IP address for TCP<");
+  }
+
+  if (sk_setup(t) < 0)
+  {
+    /* FIXME: Call err_hook instead ? */
+    log(L_ERR "SOCK: Incoming connection: %s%#m", t->err);
+
+    /* FIXME: handle it better in rfree() */
+    close(t->fd);	
+    t->fd = -1;
+    rfree(t);
+    return 1;
+  }
+
+  sk_insert(t);
+  sk_alloc_bufs(t);
+  s->rx_hook(t, 0);
+  return 1;
 }
 
 /**
@@ -1197,161 +1305,185 @@ sk_passive_connected(sock *s, struct sockaddr *sa, int al, int type)
 int
 sk_open(sock *s)
 {
-  int fd;
-  int one = 1;
+  int af = BIRD_AF;
+  int fd = -1;
   int do_bind = 0;
   int bind_port = 0;
   ip_addr bind_addr = IPA_NONE;
   sockaddr sa;
-  char *err;
 
   switch (s->type)
-    {
-    case SK_TCP_ACTIVE:
-      s->ttx = "";			/* Force s->ttx != s->tpos */
-      /* Fall thru */
-    case SK_TCP_PASSIVE:
-      fd = socket(BIRD_PF, SOCK_STREAM, IPPROTO_TCP);
-      bind_port = s->sport;
-      bind_addr = s->saddr;
-      do_bind = bind_port || ipa_nonzero(bind_addr);
-      break;
-
-    case SK_UDP:
-      fd = socket(BIRD_PF, SOCK_DGRAM, IPPROTO_UDP);
-      bind_port = s->sport;
-      bind_addr = (s->flags & SKF_BIND) ? s->saddr : IPA_NONE;
-      do_bind = 1;
-      break;
-
-    case SK_IP:
-      fd = socket(BIRD_PF, SOCK_RAW, s->dport);
-      bind_port = 0;
-      bind_addr = (s->flags & SKF_BIND) ? s->saddr : IPA_NONE;
-      do_bind = ipa_nonzero(bind_addr);
-      break;
-
-    case SK_MAGIC:
-      fd = s->fd;
-      break;
-
-    default:
-      bug("sk_open() called for invalid sock type %d", s->type);
-    }
+  {
+  case SK_TCP_ACTIVE:
+    s->ttx = "";			/* Force s->ttx != s->tpos */
+    /* Fall thru */
+  case SK_TCP_PASSIVE:
+    fd = socket(af, SOCK_STREAM, IPPROTO_TCP);
+    bind_port = s->sport;
+    bind_addr = s->saddr;
+    do_bind = bind_port || ipa_nonzero(bind_addr);
+    break;
+  
+  case SK_UDP:
+    fd = socket(af, SOCK_DGRAM, IPPROTO_UDP);
+    bind_port = s->sport;
+    bind_addr = (s->flags & SKF_BIND) ? s->saddr : IPA_NONE;
+    do_bind = 1;
+    break;
+
+  case SK_IP:
+    fd = socket(af, SOCK_RAW, s->dport);
+    bind_port = 0;
+    bind_addr = (s->flags & SKF_BIND) ? s->saddr : IPA_NONE;
+    do_bind = ipa_nonzero(bind_addr);
+    break;
+
+  case SK_MAGIC:
+    af = 0;
+    fd = s->fd;
+    break;
+
+  default:
+    bug("sk_open() called for invalid sock type %d", s->type);
+  }
+
   if (fd < 0)
-    die("sk_open: socket: %m");
+    ERR("socket");
+
+  s->af = af;
   s->fd = fd;
 
-  if (err = sk_setup(s))
-    goto bad;
+  if (sk_setup(s) < 0)
+    goto err;
 
   if (do_bind)
+  {
+    if (bind_port)
     {
-      if (bind_port)
-	{
-	  if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &one, sizeof(one)) < 0)
-	    ERR("SO_REUSEADDR");
+      int y = 1;
+
+      if (setsockopt(fd, SOL_SOCKET, SO_REUSEADDR, &y, sizeof(y)) < 0)
+	ERR2("SO_REUSEADDR");
 
 #ifdef CONFIG_NO_IFACE_BIND
-	  /* Workaround missing ability to bind to an iface */
-	  if ((s->type == SK_UDP) && s->iface && ipa_zero(bind_addr))
-	  {
-	    if (setsockopt(fd, SOL_SOCKET, SO_REUSEPORT, &one, sizeof(one)) < 0)
-	      ERR("SO_REUSEPORT");
-	  }
+      /* Workaround missing ability to bind to an iface */
+      if ((s->type == SK_UDP) && s->iface && ipa_zero(bind_addr))
+      {
+	if (setsockopt(fd, SOL_SOCKET, SO_REUSEPORT, &y, sizeof(y)) < 0)
+	  ERR2("SO_REUSEPORT");
+      }
 #endif
-	}
-
-      fill_in_sockaddr(&sa, bind_addr, s->iface, bind_port);
-      if (bind(fd, (struct sockaddr *) &sa, sizeof(sa)) < 0)
-	ERR("bind");
     }
 
-  fill_in_sockaddr(&sa, s->daddr, s->iface, s->dport);
+    sockaddr_fill(&sa, af, bind_addr, s->iface, bind_port);
+    if (bind(fd, &sa.sa, SA_LEN(sa)) < 0)
+      ERR2("bind");
+  }
 
   if (s->password)
-    {
-      int rv = sk_set_md5_auth_int(s, &sa, s->password);
-      if (rv < 0)
-	goto bad_no_log;
-    }
+    if (sk_set_md5_auth(s, s->daddr, s->iface, s->password) < 0)
+      goto err;
 
   switch (s->type)
-    {
-    case SK_TCP_ACTIVE:
-      if (connect(fd, (struct sockaddr *) &sa, sizeof(sa)) >= 0)
-	sk_tcp_connected(s);
-      else if (errno != EINTR && errno != EAGAIN && errno != EINPROGRESS &&
-	       errno != ECONNREFUSED && errno != EHOSTUNREACH && errno != ENETUNREACH)
-	ERR("connect");
-      break;
-    case SK_TCP_PASSIVE:
-      if (listen(fd, 8))
-	ERR("listen");
-      break;
-    case SK_MAGIC:
-      break;
-    default:
-      sk_alloc_bufs(s);
-#ifdef IPV6
-#ifdef IPV6_MTU_DISCOVER
-      {
-	int dont = IPV6_PMTUDISC_DONT;
-	if (setsockopt(fd, SOL_IPV6, IPV6_MTU_DISCOVER, &dont, sizeof(dont)) < 0)
-	  ERR("IPV6_MTU_DISCOVER");
-      }
-#endif
-#else
-#ifdef IP_PMTUDISC
-      {
-	int dont = IP_PMTUDISC_DONT;
-	if (setsockopt(fd, SOL_IP, IP_PMTUDISC, &dont, sizeof(dont)) < 0)
-	  ERR("IP_PMTUDISC");
-      }
-#endif
-#endif
-    }
+  {
+  case SK_TCP_ACTIVE:
+    sockaddr_fill(&sa, af, s->daddr, s->iface, s->dport);
+    if (connect(fd, &sa.sa, SA_LEN(sa)) >= 0)
+      sk_tcp_connected(s);
+    else if (errno != EINTR && errno != EAGAIN && errno != EINPROGRESS &&
+	     errno != ECONNREFUSED && errno != EHOSTUNREACH && errno != ENETUNREACH)
+      ERR2("connect");
+    break;
+
+  case SK_TCP_PASSIVE:
+    if (listen(fd, 8) < 0)
+      ERR2("listen");
+    break;
+
+  case SK_MAGIC:
+    break;
+
+  default:
+    sk_alloc_bufs(s);
+  }
 
   if (!(s->flags & SKF_THREAD))
     sk_insert(s);
   return 0;
 
-bad:
-  log(L_ERR "sk_open: %s: %m", err);
-bad_no_log:
+err:
   close(fd);
   s->fd = -1;
   return -1;
 }
 
-void
+int
 sk_open_unix(sock *s, char *name)
 {
-  int fd;
   struct sockaddr_un sa;
-  char *err;
+  int fd;
+
+  /* We are sloppy during error (leak fd and not set s->err), but we die anyway */
 
   fd = socket(AF_UNIX, SOCK_STREAM, 0);
   if (fd < 0)
-    ERR("socket");
-  s->fd = fd;
-  if (err = sk_setup(s))
-    goto bad;
-  unlink(name);
+    return -1;
+
+  if (fcntl(fd, F_SETFL, O_NONBLOCK) < 0)
+    return -1;
 
   /* Path length checked in test_old_bird() */
   sa.sun_family = AF_UNIX;
   strcpy(sa.sun_path, name);
+
   if (bind(fd, (struct sockaddr *) &sa, SUN_LEN(&sa)) < 0)
-    ERR("bind");
-  if (listen(fd, 8))
-    ERR("listen");
+    return -1;
+
+  if (listen(fd, 8) < 0)
+    return -1;
+
+  s->fd = fd;
   sk_insert(s);
-  return;
+  return 0;
+}
+
+
+#define CMSG_RX_SPACE MAX(CMSG4_SPACE_PKTINFO+CMSG4_SPACE_TTL, \
+			  CMSG6_SPACE_PKTINFO+CMSG6_SPACE_TTL)
+#define CMSG_TX_SPACE MAX(CMSG4_SPACE_PKTINFO,CMSG6_SPACE_PKTINFO)
+
+static void
+sk_prepare_cmsgs(sock *s, struct msghdr *msg, void *cbuf, size_t cbuflen)
+{
+  if (sk_is_ipv4(s))
+    sk_prepare_cmsgs4(s, msg, cbuf, cbuflen);
+  else
+    sk_prepare_cmsgs6(s, msg, cbuf, cbuflen);
+}
+
+static void
+sk_process_cmsgs(sock *s, struct msghdr *msg)
+{
+  struct cmsghdr *cm;
+
+  s->laddr = IPA_NONE;
+  s->lifindex = 0;
+  s->rcv_ttl = -1;
 
- bad:
-  log(L_ERR "sk_open_unix: %s: %m", err);
-  die("Unable to create control socket %s", name);
+  for (cm = CMSG_FIRSTHDR(msg); cm != NULL; cm = CMSG_NXTHDR(msg, cm))
+  {
+    if ((cm->cmsg_level == SOL_IP) && sk_is_ipv4(s))
+    {
+      sk_process_cmsg4_pktinfo(s, cm);
+      sk_process_cmsg4_ttl(s, cm);
+    }
+
+    if ((cm->cmsg_level == SOL_IPV6) && sk_is_ipv6(s))
+    {
+      sk_process_cmsg6_pktinfo(s, cm);
+      sk_process_cmsg6_ttl(s, cm);
+    }
+  }
 }
 
 
@@ -1362,11 +1494,11 @@ sk_sendmsg(sock *s)
   byte cmsg_buf[CMSG_TX_SPACE];
   sockaddr dst;
 
-  fill_in_sockaddr(&dst, s->daddr, s->iface, s->dport);
+  sockaddr_fill(&dst, s->af, s->daddr, s->iface, s->dport);
 
   struct msghdr msg = {
-    .msg_name = &dst,
-    .msg_namelen = sizeof(dst),
+    .msg_name = &dst.sa,
+    .msg_namelen = SA_LEN(dst),
     .msg_iov = &iov,
     .msg_iovlen = 1
   };
@@ -1377,14 +1509,14 @@ sk_sendmsg(sock *s)
 
   if (s->flags & SKF_HDRINCL)
   {
-    fill_ip_header(s, hdr, iov.iov_len);
+    sk_prepare_ip_header(s, hdr, iov.iov_len);
     msg.msg_iov = iov2;
     msg.msg_iovlen = 2;
   }
 #endif
 
   if (s->flags & SKF_PKTINFO)
-    sysio_prepare_tx_cmsgs(s, &msg, cmsg_buf, sizeof(cmsg_buf));
+    sk_prepare_cmsgs(s, &msg, cmsg_buf, sizeof(cmsg_buf));
 
   return sendmsg(s->fd, &msg, 0);
 }
@@ -1397,8 +1529,8 @@ sk_recvmsg(sock *s)
   sockaddr src;
 
   struct msghdr msg = {
-    .msg_name = &src,
-    .msg_namelen = sizeof(src),
+    .msg_name = &src.sa,
+    .msg_namelen = sizeof(src), // XXXX ??
     .msg_iov = &iov,
     .msg_iovlen = 1,
     .msg_control = cmsg_buf,
@@ -1415,8 +1547,8 @@ sk_recvmsg(sock *s)
   //    rv = ipv4_skip_header(pbuf, rv);
   //endif
 
-  get_sockaddr(&src, &s->faddr, NULL, &s->fport, 1);
-  sysio_process_rx_cmsgs(s, &msg);
+  sockaddr_read(&src, s->af, &s->faddr, NULL, &s->fport);
+  sk_process_cmsgs(s, &msg);
 
   if (msg.msg_flags & MSG_TRUNC)
     s->flags |= SKF_TRUNCATED;
@@ -1435,55 +1567,57 @@ sk_maybe_write(sock *s)
   int e;
 
   switch (s->type)
+  {
+  case SK_TCP:
+  case SK_MAGIC:
+  case SK_UNIX:
+    while (s->ttx != s->tpos)
     {
-    case SK_TCP:
-    case SK_MAGIC:
-    case SK_UNIX:
-      while (s->ttx != s->tpos)
+      e = write(s->fd, s->ttx, s->tpos - s->ttx);
+
+      if (e < 0)
+      {
+	if (errno != EINTR && errno != EAGAIN)
 	{
-	  e = write(s->fd, s->ttx, s->tpos - s->ttx);
-	  if (e < 0)
-	    {
-	      if (errno != EINTR && errno != EAGAIN)
-		{
-		  reset_tx_buffer(s);
-		  /* EPIPE is just a connection close notification during TX */
-		  s->err_hook(s, (errno != EPIPE) ? errno : 0);
-		  return -1;
-		}
-	      return 0;
-	    }
-	  s->ttx += e;
+	  reset_tx_buffer(s);
+	  /* EPIPE is just a connection close notification during TX */
+	  s->err_hook(s, (errno != EPIPE) ? errno : 0);
+	  return -1;
 	}
-      reset_tx_buffer(s);
-      return 1;
-    case SK_UDP:
-    case SK_IP:
-      {
-	if (s->tbuf == s->tpos)
-	  return 1;
-
-	e = sk_sendmsg(s);
-
-	if (e < 0)
-	  {
-	    if (errno != EINTR && errno != EAGAIN)
-	      {
-		reset_tx_buffer(s);
-		s->err_hook(s, errno);
-		return -1;
-	      }
-
-	    if (!s->tx_hook)
-	      reset_tx_buffer(s);
-	    return 0;
-	  }
-	reset_tx_buffer(s);
+	return 0;
+      }
+      s->ttx += e;
+    }
+    reset_tx_buffer(s);
+    return 1;
+
+  case SK_UDP:
+  case SK_IP:
+    {
+      if (s->tbuf == s->tpos)
 	return 1;
+
+      e = sk_sendmsg(s);
+
+      if (e < 0)
+      {
+	if (errno != EINTR && errno != EAGAIN)
+	{
+	  reset_tx_buffer(s);
+	  s->err_hook(s, errno);
+	  return -1;
+	}
+
+	if (!s->tx_hook)
+	  reset_tx_buffer(s);
+	return 0;
       }
-    default:
-      bug("sk_maybe_write: unknown socket type %d", s->type);
+      reset_tx_buffer(s);
+      return 1;
     }
+  default:
+    bug("sk_maybe_write: unknown socket type %d", s->type);
+  }
 }
 
 int
@@ -1573,88 +1707,86 @@ int
 sk_read(sock *s)
 {
   switch (s->type)
+  {
+  case SK_TCP_PASSIVE:
+    return sk_passive_connected(s, SK_TCP);
+
+  case SK_UNIX_PASSIVE:
+    return sk_passive_connected(s, SK_UNIX);
+
+  case SK_TCP:
+  case SK_UNIX:
     {
-    case SK_TCP_PASSIVE:
-      {
-	sockaddr sa;
-	return sk_passive_connected(s, (struct sockaddr *) &sa, sizeof(sa), SK_TCP);
-      }
-    case SK_UNIX_PASSIVE:
+      int c = read(s->fd, s->rpos, s->rbuf + s->rbsize - s->rpos);
+
+      if (c < 0)
       {
-	struct sockaddr_un sa;
-	return sk_passive_connected(s, (struct sockaddr *) &sa, sizeof(sa), SK_UNIX);
+	if (errno != EINTR && errno != EAGAIN)
+	  s->err_hook(s, errno);
       }
-    case SK_TCP:
-    case SK_UNIX:
+      else if (!c)
+	s->err_hook(s, 0);
+      else
       {
-	int c = read(s->fd, s->rpos, s->rbuf + s->rbsize - s->rpos);
-
-	if (c < 0)
-	  {
-	    if (errno != EINTR && errno != EAGAIN)
-	      s->err_hook(s, errno);
-	  }
-	else if (!c)
-	  s->err_hook(s, 0);
-	else
-	  {
-	    s->rpos += c;
-	    if (s->rx_hook(s, s->rpos - s->rbuf))
-	      {
-		/* We need to be careful since the socket could have been deleted by the hook */
-		if (current_sock == s)
-		  s->rpos = s->rbuf;
-	      }
-	    return 1;
-	  }
-	return 0;
+	s->rpos += c;
+	if (s->rx_hook(s, s->rpos - s->rbuf))
+	{
+	  /* We need to be careful since the socket could have been deleted by the hook */
+	  if (current_sock == s)
+	    s->rpos = s->rbuf;
+	}
+	return 1;
       }
-    case SK_MAGIC:
-      return s->rx_hook(s, 0);
-    default:
-      {
-	int e;
+      return 0;
+    }
 
-	e = sk_recvmsg(s);
+  case SK_MAGIC:
+    return s->rx_hook(s, 0);
 
-	if (e < 0)
-	  {
-	    if (errno != EINTR && errno != EAGAIN)
-	      s->err_hook(s, errno);
-	    return 0;
-	  }
+  default:
+    {
+      int e = sk_recvmsg(s);
 
-	s->rpos = s->rbuf + e;
-	s->rx_hook(s, e);
-	return 1;
+      if (e < 0)
+      {
+	if (errno != EINTR && errno != EAGAIN)
+	  s->err_hook(s, errno);
+	return 0;
       }
+
+      s->rpos = s->rbuf + e;
+      s->rx_hook(s, e);
+      return 1;
     }
+  }
 }
 
 int
 sk_write(sock *s)
 {
   switch (s->type)
+  {
+  case SK_TCP_ACTIVE:
     {
-    case SK_TCP_ACTIVE:
-      {
-	sockaddr sa;
-	fill_in_sockaddr(&sa, s->daddr, s->iface, s->dport);
-	if (connect(s->fd, (struct sockaddr *) &sa, sizeof(sa)) >= 0 || errno == EISCONN)
-	  sk_tcp_connected(s);
-	else if (errno != EINTR && errno != EAGAIN && errno != EINPROGRESS)
-	  s->err_hook(s, errno);
-	return 0;
-      }
-    default:
-      if (s->ttx != s->tpos && sk_maybe_write(s) > 0)
-	{
-	  if (s->tx_hook)
-	    s->tx_hook(s);
-	  return 1;
-	}
+      sockaddr sa;
+      sockaddr_fill(&sa, s->af, s->daddr, s->iface, s->dport);
+
+      if (connect(s->fd, &sa.sa, SA_LEN(sa)) >= 0 || errno == EISCONN)
+	sk_tcp_connected(s);
+      else if (errno != EINTR && errno != EAGAIN && errno != EINPROGRESS)
+	s->err_hook(s, errno);
       return 0;
     }
+
+  default:
+    if (s->ttx != s->tpos && sk_maybe_write(s) > 0)
+    {
+      if (s->tx_hook)
+	s->tx_hook(s);
+      return 1;
+    }
+    return 0;
+  }
 }
 
 void
@@ -1665,16 +1797,14 @@ sk_dump_all(void)
 
   debug("Open sockets:\n");
   WALK_LIST(n, sock_list)
-    {
-      s = SKIP_BACK(sock, n, n);
-      debug("%p ", s);
-      sk_dump(&s->r);
-    }
+  {
+    s = SKIP_BACK(sock, n, n);
+    debug("%p ", s);
+    sk_dump(&s->r);
+  }
   debug("\n");
 }
 
-#undef ERR
-#undef WARN
 
 /*
  *	Main I/O Loop
diff --git a/sysdep/unix/main.c b/sysdep/unix/main.c
index 31094c52..61b306dc 100644
--- a/sysdep/unix/main.c
+++ b/sysdep/unix/main.c
@@ -463,7 +463,12 @@ cli_init_unix(uid_t use_uid, gid_t use_gid)
   s->type = SK_UNIX_PASSIVE;
   s->rx_hook = cli_connect;
   s->rbsize = 1024;
-  sk_open_unix(s, path_control_socket);
+
+  /* Return value intentionally ignored */
+  unlink(path_control_socket);
+
+  if (sk_open_unix(s, path_control_socket) < 0)
+    die("Cannot create control socket %s: %m", path_control_socket);
 
   if (use_uid || use_gid)
     if (chown(path_control_socket, use_uid, use_gid) < 0)
diff --git a/sysdep/unix/unix.h b/sysdep/unix/unix.h
index 346adcf2..518713bc 100644
--- a/sysdep/unix/unix.h
+++ b/sysdep/unix/unix.h
@@ -12,6 +12,8 @@
 #include <sys/socket.h>
 
 struct pool;
+struct iface;
+struct birdsock;
 
 /* main.c */
 
@@ -27,36 +29,81 @@ void cmd_shutdown(void);
 
 #define UNIX_DEFAULT_CONFIGURE_TIMEOUT 300
 
+
 /* io.c */
 
-volatile int async_config_flag;
-volatile int async_dump_flag;
-volatile int async_shutdown_flag;
+#define ERR(c) do { s->err = c; return -1; } while (0)
+#define ERR2(c) do { s->err = c; goto err; } while (0)
+#define ERR_MSG(c) do { errno = 0; s->err = c; return -1; } while (0)
+
+
+#define SOCKADDR_SIZE 32
+
+typedef struct sockaddr_bird {
+  struct sockaddr sa;
+  char padding[SOCKADDR_SIZE - sizeof(struct sockaddr)];
+} sockaddr;
+
 
 #ifdef IPV6
-#define BIRD_PF PF_INET6
 #define BIRD_AF AF_INET6
-typedef struct sockaddr_in6 sockaddr;
-static inline int sa_family_check(sockaddr *sa) { return sa->sin6_family == AF_INET6; }
+#define _MI6(x1,x2,x3,x4) _MI(x1, x2, x3, x4)
+#define ipa_is_link_local(x) ipa_has_link_scope(x)
+#define ipa_from_sa(x) ipa_from_sa6(x)
+#define ipa_from_u32(x) _MI6(0,0,0xffff,x)
+#define ipa_to_u32(x) _I3(x)
 #else
-#define BIRD_PF PF_INET
 #define BIRD_AF AF_INET
-typedef struct sockaddr_in sockaddr;
-static inline int sa_family_check(sockaddr *sa) { return sa->sin_family == AF_INET; }
+#define _I0(X) 0
+#define _I1(X) 0
+#define _I2(X) 0
+#define _I3(X) 0
+#define _MI6(x1,x2,x3,x4) IPA_NONE
+#define ipa_is_link_local(x) 0
+#define ipa_from_sa(x) ipa_from_sa4(x)
 #endif
 
+
+/* This is sloppy hack, it should be detected by configure script */
+/* Linux systems have it defined so this is definition for BSD systems */
+#ifndef s6_addr32
+#define s6_addr32 __u6_addr.__u6_addr32
+#endif
+
+
+static inline ip_addr ipa_from_in4(struct in_addr a)
+{ return ipa_from_u32(ntohl(a.s_addr)); }
+
+static inline ip_addr ipa_from_in6(struct in6_addr a)
+{ return _MI6(ntohl(a.s6_addr32[0]), ntohl(a.s6_addr32[1]), ntohl(a.s6_addr32[2]), ntohl(a.s6_addr32[3])); }
+
+static inline ip_addr ipa_from_sa4(sockaddr *sa)
+{ return ipa_from_in4(((struct sockaddr_in *) sa)->sin_addr); }
+
+static inline ip_addr ipa_from_sa6(sockaddr *sa)
+{ return ipa_from_in6(((struct sockaddr_in6 *) sa)->sin6_addr); }
+
+static inline struct in_addr ipa_to_in4(ip_addr a)
+{ return (struct in_addr) { htonl(ipa_to_u32(a)) }; }
+
+static inline struct in6_addr ipa_to_in6(ip_addr a)
+{ return (struct in6_addr) { .s6_addr32 = { htonl(_I0(a)), htonl(_I1(a)), htonl(_I2(a)), htonl(_I3(a)) } }; }
+
+void sockaddr_fill(sockaddr *sa, int af, ip_addr a, struct iface *ifa, uint port);
+int sockaddr_read(sockaddr *sa, int af, ip_addr *a, struct iface **ifa, uint *port);
+
+
 #ifndef SUN_LEN
 #define SUN_LEN(ptr) ((size_t) (((struct sockaddr_un *) 0)->sun_path) + strlen ((ptr)->sun_path))
 #endif
 
-struct birdsock;
-struct iface;
+volatile int async_config_flag;
+volatile int async_dump_flag;
+volatile int async_shutdown_flag;
 
 void io_init(void);
 void io_loop(void);
-void fill_in_sockaddr(sockaddr *sa, ip_addr a, struct iface *ifa, unsigned port);
-void get_sockaddr(sockaddr *sa, ip_addr *a, struct iface **ifa, unsigned *port, int check);
-void sk_open_unix(struct birdsock *s, char *name);
+int sk_open_unix(struct birdsock *s, char *name);
 void *tracked_fopen(struct pool *, char *name, char *mode);
 void test_old_bird(char *path);