Router Advertisementv2.60test14

15 files changed, 758 insertions, 121 deletions

diff --git a/Makefile b/Makefile
index 0e047cf..dab6a9c 100644
--- a/Makefile
+++ b/Makefile
@@ -47,9 +47,11 @@ VERSION=    -DVERSION='\"`../bld/get-version`\"'
 
 OBJS = cache.o rfc1035.o util.o option.o forward.o network.o \
        dnsmasq.o dhcp.o lease.o rfc2131.o netlink.o dbus.o bpf.o \
-       helper.o tftp.o log.o conntrack.o dhcp6.o rfc3315.o dhcp-common.o 
+       helper.o tftp.o log.o conntrack.o dhcp6.o rfc3315.o \
+       dhcp-common.o outpacket.o radv.o
 
-HDRS = dnsmasq.h config.h dhcp_protocol.h dhcp6_protocol.h dns_protocol.h
+HDRS = dnsmasq.h config.h dhcp_protocol.h dhcp6_protocol.h \
+       dns_protocol.h radv_protocol.h
 
 
 all : $(BUILDDIR)
diff --git a/bld/Android.mk b/bld/Android.mk
index 413b325..a4bc610 100644
--- a/bld/Android.mk
+++ b/bld/Android.mk
@@ -7,7 +7,8 @@ LOCAL_SRC_FILES :=  bpf.c cache.c dbus.c dhcp.c dnsmasq.c \
                     forward.c helper.c lease.c log.c \
                     netlink.c network.c option.c rfc1035.c \
 		    rfc2131.c tftp.c util.c conntrack.c \
-		    dhcp6.c rfc3315.c dhcp-common.c 
+		    dhcp6.c rfc3315.c dhcp-common.c outpacket.c \
+		    radv.c
 
 LOCAL_MODULE := dnsmasq
 
diff --git a/man/dnsmasq.8 b/man/dnsmasq.8
index 3c761df..8707360 100644
--- a/man/dnsmasq.8
+++ b/man/dnsmasq.8
@@ -529,14 +529,18 @@ The optional
 sets an alphanumeric label which marks this network so that
 dhcp options may be specified on a per-network basis. 
 When it is prefixed with 'tag:' instead, then its meaning changes from setting
-a tag to matching it. Only one tag may be set, but more than one tag may be matched.
+a tag to matching it. Only one tag may be set, but more than one tag
+may be matched.
+
 The end address may be replaced by the keyword 
 .B static
 which tells dnsmasq to enable DHCP for the network specified, but not
 to dynamically allocate IP addresses: only hosts which have static
 addresses given via 
 .B dhcp-host
-or from /etc/ethers will be served. The end address may be replaced by
+or from /etc/ethers will be served. 
+
+The end address may be replaced by
 the keyword
 .B proxy
 in which case dnsmasq will provide proxy-DHCP on the specified
@@ -546,6 +550,14 @@ and
 .B pxe-service
 for details, applies to IPv4 only.)
 
+The end address may be replaced by
+the keyword
+.B ra-only
+which tells dnsmasq to offer Router Advertisement only on this subnet,
+and not DHCP. This applies to IPv6 only, see
+.B enable-ra
+for details.
+
 The interface:<interface name> section is not normally used. See the
 NOTES section for details of this.
 .TP
@@ -1234,6 +1246,20 @@ added into dnsmasq's DNS view. This flag suppresses that behaviour,
 this is useful, for instance, to allow Windows clients to update
 Active Directory servers. See RFC 4702 for details. 
 .TP
+.B --enable-ra
+Enable dnsmasq's IPv6 Router Advertisement feature. DHCPv6 doesn't
+handle complete network configuration in the same way as DHCPv4. Router
+discovery and (possibly) prefix discovery for autonomous address
+creation are handled by a different protocol. When DHCP is in use,
+only a subset of this is needed, and dnsmasq can handle it, using
+existing DHCP configuration to provide most data. When RA is enabled,
+dnsmasq will advertise a prefix for each dhcp-range, with default
+router and recursive DNS server as the relevant link-local address on 
+the machine running dnsmasq. The "managed address" bits are set,
+except for a dhcp-range which is marked as "ra-only". In which case RA
+is provided by no DHCPv6 service and the managed address bits are
+cleared.
+.TP
 .B --enable-tftp[=<interface>]
 Enable the TFTP server function. This is deliberately limited to that
 needed to net-boot a client. Only reading is allowed; the tsize and
diff --git a/src/bpf.c b/src/bpf.c
index 2cd9ada..9619764 100644
--- a/src/bpf.c
+++ b/src/bpf.c
@@ -199,7 +199,8 @@ int iface_enumerate(int family, void *parm, int (*callback)())
 	    { 
 	      /* Assume ethernet again here */
 	      struct sockaddr_dl *sdl = (struct sockaddr_dl *)&ifr->ifr_addr;
-	      if (sdl->sdl_alen != 0 && !((*callback)(ARPHRD_ETHER, LLADDR(sdl), sdl->sdl_alen, parm)))
+	      if (sdl->sdl_alen != 0 && !((*callback)((int)if_nametoindex(ifr->ifr_name),
+						      ARPHRD_ETHER, LLADDR(sdl), sdl->sdl_alen, parm)))
 		goto err;
 	    }
 #endif 
diff --git a/src/dhcp-common.c b/src/dhcp-common.c
index 8b8bb67..cf2c875 100644
--- a/src/dhcp-common.c
+++ b/src/dhcp-common.c
@@ -53,14 +53,14 @@ ssize_t recv_dhcp_packet(int fd, struct msghdr *msg)
 
       /* Very new Linux kernels return the actual size needed, 
 	 older ones always return truncated size */
-      if ((size_t)sz == daemon->dhcp_packet.iov_len)
+      if ((size_t)sz == msg->msg_iov->iov_len)
 	{
-	  if (!expand_buf(&daemon->dhcp_packet, sz + 100))
+	  if (!expand_buf(msg->msg_iov, sz + 100))
 	    return -1;
 	}
       else
 	{
-	  expand_buf(&daemon->dhcp_packet, sz);
+	  expand_buf(msg->msg_iov, sz);
 	  break;
 	}
     }
diff --git a/src/dhcp6.c b/src/dhcp6.c
index 6c20a0f..3b4da60 100644
--- a/src/dhcp6.c
+++ b/src/dhcp6.c
@@ -35,7 +35,7 @@ static int join_multicast(struct in6_addr *local, int prefix,
 static int complete_context6(struct in6_addr *local,  int prefix,
 			     int scope, int if_index, int dad, void *vparam);
 
-static int make_duid1(unsigned int type, char *mac, size_t maclen, void *parm); 
+static int make_duid1(int index, unsigned int type, char *mac, size_t maclen, void *parm); 
 
 void dhcp6_init(void)
 {
@@ -101,6 +101,13 @@ static int join_multicast(struct in6_addr *local, int prefix,
     if (if_index == listenp->fd_or_iface)
       return 1;
   
+  mreq.ipv6mr_interface = if_index;
+  inet_pton(AF_INET6, ALL_ROUTERS, &mreq.ipv6mr_multiaddr);
+  
+  if (daemon->icmp6fd != -1 &&
+      setsockopt(daemon->icmp6fd, IPPROTO_IPV6, IPV6_JOIN_GROUP, &mreq, sizeof(mreq)) == -1)
+    return 0;
+
   if (!indextoname(fd, if_index, ifrn_name))
     return 0;
 
@@ -120,7 +127,6 @@ static int join_multicast(struct in6_addr *local, int prefix,
   if (!context)
     return 1;
 
-  mreq.ipv6mr_interface = if_index;
   inet_pton(AF_INET6, ALL_RELAY_AGENTS_AND_SERVERS, &mreq.ipv6mr_multiaddr);
   
   if (setsockopt(fd, IPPROTO_IPV6, IPV6_JOIN_GROUP, &mreq, sizeof(mreq)) == -1)
@@ -151,7 +157,7 @@ void dhcp6_packet(time_t now)
     struct cmsghdr align; /* this ensures alignment */
     char control6[CMSG_SPACE(sizeof(struct in6_pktinfo))];
   } control_u;
-  union mysockaddr from;
+  struct sockaddr_in6 from;
   struct all_addr dest;
   ssize_t sz; 
   struct ifreq ifr;
@@ -215,8 +221,8 @@ void dhcp6_packet(time_t now)
   
   lease_prune(NULL, now); /* lose any expired leases */
 
-  msg.msg_iov =  &daemon->dhcp_packet;
-  sz = dhcp6_reply(parm.current, if_index, ifr.ifr_name, &parm.fallback, sz, IN6_IS_ADDR_MULTICAST(&from.in6.sin6_addr), now);
+  sz = dhcp6_reply(parm.current, if_index, ifr.ifr_name, &parm.fallback, 
+		   sz, IN6_IS_ADDR_MULTICAST(&from.sin6_addr), now);
   
   lease_update_file(now);
   lease_update_dns();
@@ -455,13 +461,15 @@ void make_duid(time_t now)
     die("Cannot create DHCPv6 server DUID: %s", NULL, EC_MISC);
 }
 
-static int make_duid1(unsigned int type, char *mac, size_t maclen, void *parm)
+static int make_duid1(int index, unsigned int type, char *mac, size_t maclen, void *parm)
 {
   /* create DUID as specified in RFC3315. We use the MAC of the
      first interface we find that isn't loopback or P-to-P */
   
   unsigned char *p;
 
+  (void)index;
+
   daemon->duid = p = safe_malloc(maclen + 8);
   daemon->duid_len = maclen + 8;
   
diff --git a/src/dnsmasq.c b/src/dnsmasq.c
index b01c3fc..d24300c 100644
--- a/src/dnsmasq.c
+++ b/src/dnsmasq.c
@@ -157,8 +157,14 @@ int main (int argc, char **argv)
       if (daemon->dhcp)
 	dhcp_init();
 #ifdef HAVE_DHCP6
+      daemon->icmp6fd = -1;
       if (daemon->dhcp6)
-	dhcp6_init();
+	{
+	  /* ra_init before dhcp6_init, so dhcp6_init can setup multicast listening */
+	  if (option_bool(OPT_RA))
+	    ra_init(now); 
+	  dhcp6_init();
+	}
 #endif
     }
 #endif
@@ -495,6 +501,9 @@ int main (int argc, char **argv)
 
   if (daemon->max_logs != 0)
     my_syslog(LOG_INFO, _("asynchronous logging enabled, queue limit is %d messages"), daemon->max_logs);
+ 
+  if (option_bool(OPT_RA))
+    my_syslog(MS_DHCP | LOG_INFO, _("IPv6 router advertisement enabled"));
 
 #ifdef HAVE_DHCP
   if (daemon->dhcp || daemon->dhcp6)
@@ -525,6 +534,8 @@ int main (int argc, char **argv)
 	  my_syslog(MS_DHCP | LOG_INFO, 
 		    (dhcp_tmp->flags & CONTEXT_STATIC) ? 
 		    _("DHCP, static leases only on %.0s%s, lease time %s") :
+		    (dhcp_tmp->flags & CONTEXT_RA_ONLY) ? 
+		    _("router advertisement only on %.0s%s, lifetime %s") :
 		    (dhcp_tmp->flags & CONTEXT_PROXY) ?
 		    _("DHCP, proxy on subnet %.0s%s%.0s") :
 		    _("DHCP, IP range %s -- %s, lease time %s"),
@@ -535,7 +546,10 @@ int main (int argc, char **argv)
       if (family == AF_INET)
 	{
 	  family = AF_INET6;
-	  dhcp_tmp = daemon->dhcp6;
+	  if (daemon->ra_contexts)
+	    dhcp_tmp = daemon->ra_contexts;
+	  else
+	    dhcp_tmp = daemon->dhcp6;
 	  goto again;
 	}
 #endif
@@ -652,7 +666,13 @@ int main (int argc, char **argv)
       if (daemon->dhcp6)
 	{
 	  FD_SET(daemon->dhcp6fd, &rset);
-	   bump_maxfd(daemon->dhcp6fd, &maxfd);
+	  bump_maxfd(daemon->dhcp6fd, &maxfd);
+	  
+	  if (daemon->icmp6fd != -1)
+	    {
+	      FD_SET(daemon->icmp6fd, &rset);
+	      bump_maxfd(daemon->icmp6fd, &maxfd); 
+	    }
 	}
 #endif
 
@@ -756,6 +776,9 @@ int main (int argc, char **argv)
 	{
 	  if (FD_ISSET(daemon->dhcp6fd, &rset))
 	    dhcp6_packet(now);
+
+	  if (daemon->icmp6fd != -1 && FD_ISSET(daemon->icmp6fd, &rset))
+	    icmp6_packet();
 	}
 #endif
 
@@ -1372,7 +1395,15 @@ int icmp_ping(struct in_addr addr)
       FD_SET(fd, &rset);
       set_dns_listeners(now, &rset, &maxfd);
       set_log_writer(&wset, &maxfd);
-
+      
+#ifdef HAVE_DHCP6
+      if (daemon->icmp6fd != -1)
+	{
+	  FD_SET(daemon->icmp6fd, &rset);
+	  bump_maxfd(daemon->icmp6fd, &maxfd); 
+	}
+#endif
+      
       if (select(maxfd+1, &rset, &wset, NULL, &tv) < 0)
 	{
 	  FD_ZERO(&rset);
@@ -1384,6 +1415,11 @@ int icmp_ping(struct in_addr addr)
       check_log_writer(&wset);
       check_dns_listeners(&rset, now);
 
+#ifdef HAVE_DHCP6
+      if (daemon->icmp6fd != -1 && FD_ISSET(daemon->icmp6fd, &rset))
+	icmp6_packet();
+#endif
+      
 #ifdef HAVE_TFTP
       check_tftp_listeners(&rset, now);
 #endif
diff --git a/src/dnsmasq.h b/src/dnsmasq.h
index 575d9a7..a30fb17 100644
--- a/src/dnsmasq.h
+++ b/src/dnsmasq.h
@@ -60,6 +60,7 @@ typedef unsigned long long u64;
 #include "dhcp_protocol.h"
 #ifdef HAVE_DHCP6
 #include "dhcp6_protocol.h"
+#include "radv_protocol.h"
 #endif
 
 #define gettext_noop(S) (S)
@@ -215,7 +216,8 @@ struct event_desc {
 #define OPT_CONSEC_ADDR    34
 #define OPT_CONNTRACK      35
 #define OPT_FQDN_UPDATE    36
-#define OPT_LAST           37
+#define OPT_RA             37
+#define OPT_LAST           38
 
 /* extra flags for my_syslog, we use a couple of facilities since they are known 
    not to occupy the same bits as priorities, no matter how syslog.h is set up. */
@@ -605,6 +607,7 @@ struct dhcp_context {
   struct in6_addr start6, end6; /* range of available addresses */
   struct in6_addr local6;
   int prefix;
+  time_t ra_time;
 #endif
   int flags;
   char *interface;
@@ -616,6 +619,8 @@ struct dhcp_context {
 #define CONTEXT_NETMASK   2
 #define CONTEXT_BRDCAST   4
 #define CONTEXT_PROXY     8
+#define CONTEXT_RA_ONLY  16
+#define CONTEXT_RA_DONE  32
 
 struct ping_result {
   struct in_addr addr;
@@ -694,7 +699,7 @@ extern struct daemon {
   int port, query_port, min_port;
   unsigned long local_ttl, neg_ttl, max_ttl;
   struct hostsfile *addn_hosts;
-  struct dhcp_context *dhcp, *dhcp6;
+  struct dhcp_context *dhcp, *dhcp6, *ra_contexts;
   struct dhcp_config *dhcp_conf;
   struct dhcp_opt *dhcp_opts, *dhcp_match, *dhcp_opts6, *dhcp_match6;
   struct dhcp_vendor *dhcp_vendors;
@@ -754,7 +759,7 @@ extern struct daemon {
   int duid_len;
   unsigned char *duid;
   struct iovec outpacket;
-  int dhcp6fd;
+  int dhcp6fd, icmp6fd;
 #endif
   /* DBus stuff */
   /* void * here to avoid depending on dbus headers outside dbus.c */
@@ -1054,3 +1059,24 @@ int match_bytes(struct dhcp_opt *o, unsigned char *p, int len);
 void dhcp_update_configs(struct dhcp_config *configs);
 void check_dhcp_hosts(int fatal);
 #endif
+
+/* outpacket.c */
+#ifdef HAVE_DHCP6
+void end_opt6(int container);
+int save_counter(int newval);
+void *expand(size_t headroom);
+int new_opt6(int opt);
+void *put_opt6(void *data, size_t len);
+void put_opt6_long(unsigned int val);
+void put_opt6_short(unsigned int val);
+void put_opt6_char(unsigned int val);
+void put_opt6_string(char *s);
+#endif
+
+/* radv.c */
+#ifdef HAVE_DHCP6
+void ra_init(time_t now);
+void icmp6_packet(void);
+time_t periodic_ra(time_t now);
+void ra_start_unsolicted(time_t now);
+#endif
diff --git a/src/lease.c b/src/lease.c
index 57fde0f..49ce016 100644
--- a/src/lease.c
+++ b/src/lease.c
@@ -313,7 +313,15 @@ void lease_update_file(time_t now)
     }
   
   /* Set alarm for when the first lease expires + slop. */
-  for (next_event = 0, lease = leases; lease; lease = lease->next)
+  next_event = 0;
+
+#ifdef HAVE_DHCP6
+  /* do timed RAs and determine when the next is */
+  if (option_bool(OPT_RA))
+    next_event = periodic_ra(now);
+#endif
+
+  for (lease = leases; lease; lease = lease->next)
     if (lease->expires != 0 &&
 	(next_event == 0 || difftime(next_event, lease->expires + 10) > 0.0))
       next_event = lease->expires + 10;
diff --git a/src/netlink.c b/src/netlink.c
index a7d8fb2..820b0a8 100644
--- a/src/netlink.c
+++ b/src/netlink.c
@@ -284,7 +284,7 @@ int iface_enumerate(int family, void *parm, int (*callback)())
 	      }
 
 	    if (mac && callback_ok && !((link->ifi_flags & (IFF_LOOPBACK | IFF_POINTOPOINT))) && 
-		!((*callback)((unsigned int)link->ifi_type, mac, maclen, parm)))
+		!((*callback)((int)link->ifi_index, (unsigned int)link->ifi_type, mac, maclen, parm)))
 	      callback_ok = 0;
 	  }
 #endif
@@ -341,6 +341,17 @@ static void nl_routechange(struct nlmsghdr *h)
       /* Force re-reading resolv file right now, for luck. */
       daemon->last_resolv = 0;
       
+#ifdef HAVE_DHCP6
+      /* force RAs to sync new network and pick up new interfaces.  */
+      if (option_bool(OPT_RA))
+	{
+	  ra_start_unsolicted(dnsmasq_time());
+	  /* cause lease_update_file to run after we return, in case we were called from
+	     iface_enumerate and can't re-enter it now */
+	  alarm(1);
+	}
+#endif
+
       if (daemon->srv_save)
 	{
 	  if (daemon->srv_save->sfd)
diff --git a/src/option.c b/src/option.c
index 96277e5..c4a62c4 100644
--- a/src/option.c
+++ b/src/option.c
@@ -114,6 +114,7 @@ struct myoption {
 #define LOPT_CONNTRACK 303
 #define LOPT_FQDN      304
 #define LOPT_LUASCRIPT 305
+#define LOPT_RA        306
 
 #ifdef HAVE_GETOPT_LONG
 static const struct option opts[] =  
@@ -233,6 +234,7 @@ static const struct myoption opts[] =
     { "conntrack", 0, 0, LOPT_CONNTRACK },
     { "dhcp-client-update", 0, 0, LOPT_FQDN },
     { "dhcp-luascript", 1, 0, LOPT_LUASCRIPT },
+    { "enable-ra", 0, 0, LOPT_RA },
     { NULL, 0, 0, 0 }
   };
 
@@ -359,6 +361,7 @@ static struct {
   { LOPT_INCR_ADDR, OPT_CONSEC_ADDR, NULL, gettext_noop("Attempt to allocate sequential IP addresses to DHCP clients."), NULL },
   { LOPT_CONNTRACK, OPT_CONNTRACK, NULL, gettext_noop("Copy connection-track mark from queries to upstream connections."), NULL },
   { LOPT_FQDN, OPT_FQDN_UPDATE, NULL, gettext_noop("Allow DHCP clients to do their own DDNS updates."), NULL },
+  { LOPT_RA, OPT_RA, NULL, gettext_noop("Send router-advertisements for interfaces doing DHCPv6"), NULL },
   { 0, 0, NULL, NULL, NULL }
 }; 
 
@@ -2330,17 +2333,32 @@ static char *one_opt(int option, char *arg, char *gen_prob, int command_line)
 #ifdef HAVE_DHCP6
 	else if (inet_pton(AF_INET6, a[0], &new->start6))
 	  {
-	    new->next = daemon->dhcp6;
 	    new->prefix = 64; /* default */
-	    daemon->dhcp6 = new;
+	    
 	    if (strcmp(a[1], "static") == 0)
 	      {
 		memcpy(&new->end6, &new->start6, IN6ADDRSZ);
 		new->flags |= CONTEXT_STATIC;
 	      }
+	    else if (strcmp(a[1], "ra-only") == 0)
+	      {
+		memcpy(&new->end6, &new->start6, IN6ADDRSZ);
+		new->flags |= CONTEXT_RA_ONLY;
+	      }
 	    else if (!inet_pton(AF_INET6, a[1], &new->end6))
 	      option = '?';
 	    
+	    if (new->flags & CONTEXT_RA_ONLY)
+	      {
+		new->next = daemon->ra_contexts;
+		daemon->ra_contexts = new;
+	      }
+	    else
+	      {
+		new->next = daemon->dhcp6;
+		daemon->dhcp6 = new;
+	      }
+
 	    /* bare integer < 128 is prefix value */
 	    if (option != '?' && k >= 3)
 	      {
diff --git a/src/outpacket.c b/src/outpacket.c
new file mode 100644
index 0000000..2fa1e26
--- /dev/null
+++ b/src/outpacket.c
@@ -0,0 +1,108 @@
+/* dnsmasq is Copyright (c) 2000-2012 Simon Kelley
+
+   This program 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; version 2 dated June, 1991, or
+   (at your option) version 3 dated 29 June, 2007.
+ 
+   This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+
+#include "dnsmasq.h"
+ 
+#ifdef HAVE_DHCP6
+
+static size_t outpacket_counter;
+
+void end_opt6(int container)
+{
+   void *p = daemon->outpacket.iov_base + container + 2;
+   u16 len = outpacket_counter - container - 4 ;
+   
+   PUTSHORT(len, p);
+}
+
+int save_counter(int newval)
+{
+  int ret = outpacket_counter;
+  if (newval != -1)
+    outpacket_counter = newval;
+
+  return ret;
+}
+
+void *expand(size_t headroom)
+{
+  void *ret;
+
+  if (expand_buf(&daemon->outpacket, outpacket_counter + headroom))
+    {
+      ret = daemon->outpacket.iov_base + outpacket_counter;
+      outpacket_counter += headroom;
+      return ret;
+    }
+  
+  return NULL;
+}
+    
+int new_opt6(int opt)
+{
+  int ret = outpacket_counter;
+  void *p;
+
+  if ((p = expand(4)))
+    {
+      PUTSHORT(opt, p);
+      PUTSHORT(0, p);
+    }
+
+  return ret;
+}
+
+void *put_opt6(void *data, size_t len)
+{
+  void *p;
+
+  if ((p = expand(len)))
+    memcpy(p, data, len);   
+
+  return p;
+}
+  
+void put_opt6_long(unsigned int val)
+{
+  void *p;
+  
+  if ((p = expand(4)))  
+    PUTLONG(val, p);
+}
+
+void put_opt6_short(unsigned int val)
+{
+  void *p;
+
+  if ((p = expand(2)))
+    PUTSHORT(val, p);   
+}
+
+void put_opt6_char(unsigned int val)
+{
+  unsigned char *p;
+
+  if ((p = expand(1)))
+    *p = val;   
+}
+
+void put_opt6_string(char *s)
+{
+  put_opt6(s, strlen(s));
+}
+
+#endif
diff --git a/src/radv.c b/src/radv.c
new file mode 100644
index 0000000..f451295
--- /dev/null
+++ b/src/radv.c
@@ -0,0 +1,433 @@
+/* dnsmasq is Copyright (c) 2000-2012 Simon Kelley
+
+   This program 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; version 2 dated June, 1991, or
+   (at your option) version 3 dated 29 June, 2007.
+ 
+   This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+
+/* NB. This code may be called during a DHCPv4 transaction which is in ping-wait
+   It therefore cannot use any DHCP buffer resources except outpacket, which is
+   not used by DHCPv4 code. */
+
+#include "dnsmasq.h"
+#include <netinet/icmp6.h>
+
+#ifdef HAVE_DHCP6
+
+struct ra_param {
+  int ind, managed, found_context, first;
+  char *if_name;
+  struct in6_addr link_local;
+};
+
+struct search_param {
+  time_t now; int iface;
+};
+
+static void send_ra(int iface, char *iface_name, struct in6_addr *dest);
+static int add_prefixes(struct in6_addr *local,  int prefix,
+			int scope, int if_index, int dad, void *vparam);
+static int iface_search(struct in6_addr *local,  int prefix,
+			int scope, int if_index, int dad, void *vparam);
+static int add_lla(int index, unsigned int type, char *mac, size_t maclen, void *parm);
+
+static int unicast_hop_limit, multicast_hop_limit;
+static time_t ra_short_period_start;
+
+void ra_init(time_t now)
+{
+  struct dhcp_context *context;
+  struct icmp6_filter filter;
+  int fd;
+#if defined(IP_TOS) && defined(IPTOS_CLASS_CS6)
+  int class = IPTOS_CLASS_CS6;
+#endif
+  int val = 255; /* radvd uses this value */
+  size_t len1 = sizeof(int);
+  size_t len2 = sizeof(int);
+
+  ICMP6_FILTER_SETBLOCKALL(&filter);
+  ICMP6_FILTER_SETPASS(ND_ROUTER_SOLICIT, &filter);
+  ICMP6_FILTER_SETPASS(ND_ROUTER_ADVERT, &filter);
+  
+  if ((fd = socket(PF_INET6, SOCK_RAW, IPPROTO_ICMPV6)) == -1 ||
+      getsockopt(fd, IPPROTO_IPV6, IPV6_UNICAST_HOPS, &unicast_hop_limit, &len1) ||
+      getsockopt(fd, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &multicast_hop_limit, &len2) ||
+#if defined(IP_TOS) && defined(IPTOS_CLASS_CS6)
+      setsockopt(fd, IPPROTO_IPV6, IPV6_TCLASS, &class, sizeof(class)) == -1 ||
+#endif
+      !fix_fd(fd) ||
+      !set_ipv6pktinfo(fd) ||
+      setsockopt(fd, IPPROTO_IPV6, IPV6_UNICAST_HOPS, &val, sizeof(val)) ||
+      setsockopt(fd, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &val, sizeof(val)) ||
+      setsockopt(fd, IPPROTO_ICMPV6, ICMP6_FILTER, &filter, sizeof(filter)) == -1)
+    die (_("cannot create ICMPv6 socket: %s"), NULL, EC_BADNET);
+  
+   daemon->icmp6fd = fd;
+   
+   /* link the DHCP6 contexts to the ra-only ones so we can traverse them all 
+      from ->ra_contexts, but only the non-ra-onlies from ->dhcp6 */
+   if (!daemon->ra_contexts)
+     daemon->ra_contexts = daemon->dhcp6;
+   else
+     {
+       for (context = daemon->ra_contexts; context->next; context = context->next);
+       context->next = daemon->dhcp6;
+     }
+
+   if (!daemon->dhcp6)
+     die(_("cannot do router advertisement unless DHCPv6 is enabled"), NULL, EC_BADCONF);
+
+   ra_start_unsolicted(now);
+}
+
+void ra_start_unsolicted(time_t now)
+{   
+   struct dhcp_context *context;
+   
+   /* init timers so that we do ra's for all soon. some ra_times will end up zeroed
+     if it's not appropriate to advertise those contexts.
+     This gets re-called on a netlink route-change to re-do the advertisement
+     and pick up new interfaces */
+
+   /* range 0 - 5 */
+   for (context = daemon->ra_contexts; context; context = context->next)
+     context->ra_time = now + (rand16()/13000);
+
+   /* re-do ras after a short time, in case the first gets lost.
+      This is reset once that's done. */
+   ra_short_period_start = now;
+}
+
+void icmp6_packet(void)
+{
+  char interface[IF_NAMESIZE+1];
+  ssize_t sz; 
+  int if_index = 0;
+  struct cmsghdr *cmptr;
+  struct msghdr msg;
+  union {
+    struct cmsghdr align; /* this ensures alignment */
+    char control6[CMSG_SPACE(sizeof(struct in6_pktinfo))];
+  } control_u;
+  struct sockaddr_in6 from;
+  unsigned char *p;
+  char *mac = "";
+  struct iname *tmp;
+  struct dhcp_context *context;
+
+  /* Note: use outpacket for input buffer */
+  msg.msg_control = control_u.control6;
+  msg.msg_controllen = sizeof(control_u);
+  msg.msg_flags = 0;
+  msg.msg_name = &from;
+  msg.msg_namelen = sizeof(from);
+  msg.msg_iov = &daemon->outpacket;
+  msg.msg_iovlen = 1;
+  
+  if ((sz = recv_dhcp_packet(daemon->icmp6fd, &msg)) == -1 || sz < 8)
+    return;
+  
+  for (cmptr = CMSG_FIRSTHDR(&msg); cmptr; cmptr = CMSG_NXTHDR(&msg, cmptr))
+    if (cmptr->cmsg_level == IPPROTO_IPV6 && cmptr->cmsg_type == daemon->v6pktinfo)
+      {
+	union {
+	  unsigned char *c;
+	  struct in6_pktinfo *p;
+	} p;
+	p.c = CMSG_DATA(cmptr);
+        
+	if_index = p.p->ipi6_ifindex;
+      }
+  
+  if (!indextoname(daemon->icmp6fd, if_index, interface))
+    return;
+    
+  if (!iface_check(AF_LOCAL, NULL, interface))
+    return;
+  
+  for (tmp = daemon->dhcp_except; tmp; tmp = tmp->next)
+    if (tmp->name && (strcmp(tmp->name, interface) == 0))
+      return;
+ 
+  /* weird libvirt-inspired access control */
+  for (context = daemon->dhcp6; context; context = context->next)
+    if (!context->interface || strcmp(context->interface, interface) == 0)
+      break;
+  
+  if (!context)
+    return;
+
+  p = (unsigned char *)daemon->outpacket.iov_base;
+  
+  if (p[0] != ICMP6_ROUTER_SOLICIT || p[1] != 0)
+    return;
+  
+  /* look for link-layer address option for logging */
+  if (sz >= 16 && p[8] == ICMP6_OPT_SOURCE_MAC && (p[9] * 8) + 8 <= sz)
+    {
+      print_mac(daemon->namebuff, &p[10], (p[9] * 8) - 2);
+      mac = daemon->namebuff;
+    }
+  
+  my_syslog(MS_DHCP | LOG_INFO, "RTR-SOLICIT(%s) %s", interface, mac);
+  
+  send_ra(if_index, interface, &from.sin6_addr);
+}
+
+static void send_ra(int iface, char *iface_name, struct in6_addr *dest)
+{
+  struct ra_packet *ra;
+  struct ra_param parm;
+  struct ifreq ifr;
+  struct sockaddr_in6 addr;
+  struct dhcp_context *context;
+ 
+  save_counter(0);
+  ra = expand(sizeof(struct ra_packet));
+  
+  ra->type = ICMP6_ROUTER_ADVERT;
+  ra->code = 0;
+  ra->hop_limit = dest ? unicast_hop_limit : multicast_hop_limit;
+  ra->flags = 0;
+  ra->lifetime = htons(1800); /* AdvDefaultLifetime*/
+  ra->reachable_time = 0;
+  ra->retrans_time = 0;
+
+  parm.ind = iface;
+  parm.managed = 0;
+  parm.found_context = 0;
+  parm.if_name = iface_name;
+  parm.first = 1;
+
+  for (context = daemon->ra_contexts; context; context = context->next)
+    context->flags &= ~CONTEXT_RA_DONE;
+  
+  if (!iface_enumerate(AF_INET6, &parm, add_prefixes) ||
+      !parm.found_context)
+    return;
+
+  strncpy(ifr.ifr_name, iface_name, IF_NAMESIZE);
+  
+  if (ioctl(daemon->icmp6fd, SIOCGIFMTU, &ifr) != -1)
+    {
+      put_opt6_char(ICMP6_OPT_MTU);
+      put_opt6_char(1);
+      put_opt6_short(0);
+      put_opt6_long(ifr.ifr_mtu);
+    }
+     
+  iface_enumerate(AF_LOCAL, &iface, add_lla);
+  
+  /* RDNSS, RFC 6106 */
+  put_opt6_char(ICMP6_OPT_RDNSS);
+  put_opt6_char(3);
+  put_opt6_short(0);
+  put_opt6_long(1800); /* lifetime - twice RA retransmit */
+  put_opt6(&parm.link_local, IN6ADDRSZ);
+
+
+  /* set managed bits unless we're providing only RA on this link */
+  if (parm.managed)
+    ra->flags = 0xc0; 
+
+  /* decide where we're sending */
+  memset(&addr, 0, sizeof(addr));
+  addr.sin6_family = AF_INET6;
+  addr.sin6_port = htons(IPPROTO_ICMPV6);
+  if (dest)
+    {
+      memcpy(&addr.sin6_addr, dest, sizeof(struct in6_addr));
+      if (IN6_IS_ADDR_LINKLOCAL(dest) ||
+	  IN6_IS_ADDR_MC_LINKLOCAL(dest))
+	addr.sin6_scope_id = iface;
+    }
+  else
+    inet_pton(AF_INET6, ALL_HOSTS, &addr.sin6_addr);
+
+  send_from(daemon->icmp6fd, 0, daemon->outpacket.iov_base, save_counter(0),
+	    (union mysockaddr *)&addr, (struct all_addr *)&parm.link_local, iface); 
+  
+}
+
+static int add_prefixes(struct in6_addr *local,  int prefix,
+			int scope, int if_index, int dad, void *vparam)
+{
+  struct dhcp_context *context, *tmp;
+  struct ra_param *param = vparam;
+  struct prefix_opt *opt;
+
+  (void)scope; /* warning */
+  (void)dad;
+
+  if (if_index == param->ind)
+    {
+      if (IN6_IS_ADDR_LINKLOCAL(local))
+	param->link_local = *local;
+      else if (!IN6_IS_ADDR_LOOPBACK(local) &&
+	       !IN6_IS_ADDR_LINKLOCAL(local) &&
+	       !IN6_IS_ADDR_MULTICAST(local))
+	{
+	  for (context = daemon->ra_contexts; context; context = context->next)
+	    if (prefix == context->prefix &&
+		is_same_net6(local, &context->start6, prefix) &&
+		is_same_net6(local, &context->end6, prefix))
+	      {
+		if (!(context->flags & CONTEXT_RA_ONLY))
+		  param->managed = 1;
+	
+		if (context->flags & CONTEXT_RA_DONE)
+		  continue;
+		
+		/* subsequent prefixes on the same interface don't need timers */
+		if (!param->first)
+		  context->ra_time = 0;
+		param->first = 0;
+		param->found_context = 1;
+		context->flags |= CONTEXT_RA_DONE;
+
+		/* mark this subnet and duplicates: as done. */
+		for (tmp = context->next; tmp; tmp = tmp->next)
+		  if (tmp->prefix == prefix &&
+		      is_same_net6(local, &tmp->start6, prefix) &&
+		      is_same_net6(local, &tmp->end6, prefix))
+		    {
+		      tmp->flags |= CONTEXT_RA_DONE;
+		      context->ra_time = 0;
+		    }
+
+		if ((opt = expand(sizeof(struct prefix_opt))))
+		  {
+		    u64 addrpart = addr6part(&context->start6);
+		    u64 mask = (prefix == 64) ? (u64)-1LL : (1LLU << (128 - prefix)) - 1LLU;
+		    unsigned int time = context->lease_time;
+
+		    /* lifetimes must be min 2 hrs, by RFC 2462 */
+		    if (time < 7200)
+		      time = 7200;
+
+		    opt->type = ICMP6_OPT_PREFIX;
+		    opt->len = 4;
+		    opt->prefix_len = prefix;
+		    /* autonomous only is we're not doing dhcp */
+		    opt->flags = (context->flags & CONTEXT_RA_ONLY) ? 0xc0 : 0x00;
+		    opt->valid_lifetime = opt->preferred_lifetime = htonl(time);
+		    opt->reserved = 0;
+		    
+		    opt->prefix = context->start6;
+		    setaddr6part(&opt->prefix, addrpart & ~mask);
+		    
+		    inet_ntop(AF_INET6, &opt->prefix, daemon->addrbuff, ADDRSTRLEN);
+		    my_syslog(MS_DHCP | LOG_INFO, "RTR-ADVERT(%s) %s", param->if_name, daemon->addrbuff); 		    
+		  }
+	      }
+	}
+    }          
+  return 1;
+}
+
+static int add_lla(int index, unsigned int type, char *mac, size_t maclen, void *parm)
+{
+  (void)type;
+
+  if (index == *((int *)parm))
+    {
+      /* size is in units of 8 octets and includes type and length (2 bytes)
+	 add 7 to round up */
+      int len = (maclen + 9) >> 3;
+      unsigned char *p = expand(len << 3);
+      memset(p, 0, len << 3);
+      *p++ = ICMP6_OPT_SOURCE_MAC;
+      *p++ = len;
+      memcpy(p, mac, maclen);
+
+      return 0;
+    }
+
+  return 1;
+}
+
+time_t periodic_ra(time_t now)
+{
+  struct search_param param;
+  struct dhcp_context *context;
+  time_t next_event;
+  char interface[IF_NAMESIZE+1];
+  
+  param.now = now;
+
+  while (1)
+    {
+      /* find overdue events, and time of first future event */
+      for (next_event = 0, context = daemon->ra_contexts; context; context = context->next)
+	if (context->ra_time != 0)
+	  {
+	    if (difftime(context->ra_time, now) < 0.0)
+	      break; /* overdue */
+	    
+	    if (next_event == 0 || difftime(next_event, context->ra_time + 2) > 0.0)
+	      next_event = context->ra_time + 2;
+	  }
+      
+      /* none overdue */
+      if (!context)
+	break;
+      
+      /* There's a context overdue, but we can't find an interface
+	 associated with it, because it's for a subnet we dont 
+	 have an interface on. Probably we're doing DHCP on
+	 a remote subnet via a relay. Zero the timer, since we won't
+	 ever be able to send ra's and satistfy it. */
+      if (iface_enumerate(AF_INET6, &param, iface_search))
+	context->ra_time = 0;
+      else if (indextoname(daemon->icmp6fd, param.iface, interface))
+	send_ra(param.iface, interface, NULL); 
+    }
+  
+  return next_event;
+}
+
+static int iface_search(struct in6_addr *local,  int prefix,
+			int scope, int if_index, int dad, void *vparam)
+{
+  struct search_param *param = vparam;
+  struct dhcp_context *context, *tmp;
+
+  (void)scope;
+  (void)dad;
+ 
+  for (context = daemon->ra_contexts; context; context = context->next)
+    if (prefix == context->prefix &&
+	is_same_net6(local, &context->start6, prefix) &&
+	is_same_net6(local, &context->end6, prefix))
+      if (context->ra_time != 0 && difftime(context->ra_time, param->now) < 0.0)
+	{
+	  /* found an interface that's overdue for RA determine new 
+	     timeout value and zap other contexts on the same interface 
+	     so they don't timeout independently .*/
+	  param->iface = if_index;
+	  
+	  if (difftime(param->now, ra_short_period_start) < 60.0)
+	    /* range 5 - 20 */
+	    context->ra_time = param->now + 5 + (rand16()/4400);
+	  else
+	    /* range 450 - 600 */
+	    context->ra_time = param->now + 450 + (rand16()/440);
+	  
+	  return 0; /* found, abort */
+	}
+  
+  return 1; /* keep searching */
+}
+
+#endif
diff --git a/src/radv_protocol.h b/src/radv_protocol.h
new file mode 100644
index 0000000..8f3244f
--- /dev/null
+++ b/src/radv_protocol.h
@@ -0,0 +1,44 @@
+/* dnsmasq is Copyright (c) 2000-2012 Simon Kelley
+
+   This program 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; version 2 dated June, 1991, or
+   (at your option) version 3 dated 29 June, 2007.
+ 
+   This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#define ALL_HOSTS                 "FF02::1"
+#define ALL_ROUTERS               "FF02::2"
+
+struct ra_packet {
+  u8 type, code;
+  u16 checksum;
+  u8 hop_limit, flags;
+  u16 lifetime;
+  u32 reachable_time;
+  u32 retrans_time;
+};
+
+struct prefix_opt {
+  u8 type, len, prefix_len, flags;
+  u32 valid_lifetime, preferred_lifetime, reserved;
+  struct in6_addr prefix;
+};
+
+#define ICMP6_ROUTER_SOLICIT 133
+#define ICMP6_ROUTER_ADVERT  134
+
+#define ICMP6_OPT_SOURCE_MAC   1
+#define ICMP6_OPT_PREFIX       3
+#define ICMP6_OPT_MTU          5
+#define ICMP6_OPT_RDNSS       25
+
+
+
diff --git a/src/rfc3315.c b/src/rfc3315.c
index ed76b24..4eb6d2f 100644
--- a/src/rfc3315.c
+++ b/src/rfc3315.c
@@ -19,17 +19,6 @@
 
 #ifdef HAVE_DHCP6
 
-static size_t outpacket_counter;
-
-static void end_opt6(int container);
-static int save_counter(int newval);
-static void *expand(size_t headroom);
-static int new_opt6(int opt);
-static void *put_opt6(void *data, size_t len);
-static void put_opt6_short(unsigned int val);
-static void put_opt6_long(unsigned int val);
-static void put_opt6_string(char *s);
-
 static int dhcp6_maybe_relay(struct in6_addr *link_address, struct dhcp_netid **relay_tagsp, struct dhcp_context *context, 
 			     int interface, char *iface_name, struct in6_addr *fallback, void *inbuff, size_t sz, int is_unicast, time_t now);
 static int dhcp6_no_relay(int msg_type,  struct in6_addr *link_address, struct dhcp_netid *tags, struct dhcp_context *context, 
@@ -55,10 +44,10 @@ size_t dhcp6_reply(struct dhcp_context *context, int interface, char *iface_name
   for (vendor = daemon->dhcp_vendors; vendor; vendor = vendor->next)
     vendor->netid.next = &vendor->netid;
   
-  outpacket_counter = 0;
+  save_counter(0);
   
   if (dhcp6_maybe_relay(NULL, &relay_tags, context, interface, iface_name, fallback, daemon->dhcp_packet.iov_base, sz, is_unicast, now))
-    return outpacket_counter;
+    return save_counter(0);
 
   return 0;
 }
@@ -1274,12 +1263,14 @@ static int dhcp6_no_relay(int msg_type, struct in6_addr *link_address, struct dh
 	len += strlen(send_domain) + 1;
 
       o = new_opt6(OPTION6_FQDN);
-      p = expand(len + 3);
-      *(p++) = fqdn_flags;
-      p = do_rfc1035_name(p, hostname);
-      if (send_domain)
-	p = do_rfc1035_name(p, send_domain);
-      *p = 0;
+      if ((p = expand(len + 3)))
+	{
+	  *(p++) = fqdn_flags;
+	  p = do_rfc1035_name(p, hostname);
+	  if (send_domain)
+	    p = do_rfc1035_name(p, send_domain);
+	  *p = 0;
+	}
       end_opt6(o);
     }
 
@@ -1422,80 +1413,4 @@ static unsigned int opt6_uint(unsigned char *opt, int offset, int size)
   return ret;
 } 
 
-static void end_opt6(int container)
-{
-   void *p = daemon->outpacket.iov_base + container + 2;
-   u16 len = outpacket_counter - container - 4 ;
-   
-   PUTSHORT(len, p);
-}
-
-static int save_counter(int newval)
-{
-  int ret = outpacket_counter;
-  if (newval != -1)
-    outpacket_counter = newval;
-
-  return ret;
-}
-
-static void *expand(size_t headroom)
-{
-  void *ret;
-
-  if (expand_buf(&daemon->outpacket, outpacket_counter + headroom))
-    {
-      ret = daemon->outpacket.iov_base + outpacket_counter;
-      outpacket_counter += headroom;
-      return ret;
-    }
-  
-  return NULL;
-}
-    
-static int new_opt6(int opt)
-{
-  int ret = outpacket_counter;
-  void *p;
-
-  if ((p = expand(4)))
-    {
-      PUTSHORT(opt, p);
-      PUTSHORT(0, p);
-    }
-
-  return ret;
-}
-
-static void *put_opt6(void *data, size_t len)
-{
-  void *p;
-
-  if ((p = expand(len)))
-    memcpy(p, data, len);   
-
-  return p;
-}
-  
-static void put_opt6_long(unsigned int val)
-{
-  void *p;
-  
-  if ((p = expand(4)))  
-    PUTLONG(val, p);
-}
-
-static void put_opt6_short(unsigned int val)
-{
-  void *p;
-
-  if ((p = expand(2)))
-    PUTSHORT(val, p);   
-}
-
-static void put_opt6_string(char *s)
-{
-  put_opt6(s, strlen(s));
-}
-
 #endif