import of dnsmasq-2.28.tar.gz

CHANGELOG

@@ -1694,3 +1694,94 @@ version 2.27
 	    Generalised the DHCP code to cope with any hardware
 	    address type, at least on Linux. *BSD is still limited to
 	    ethernet only.
+
+version 2.28
+            Eliminated all raw network access when running on
+            Linux. All DHCP network activity now goes through the IP
+            stack. Packet sockets are no longer required. Apart from
+            being a neat hack, this should also allow DHCP over IPsec
+            to work better. On *BSD and OS X, the old method of raw net
+            access through BPF is retained.
+
+	    Simplified build options. Networking is now slimmed down
+	    to a choice of "linux" or "other". Netlink is always used
+	    under Linux. Since netlink has been available since 2.2
+	    and non-optional in an IPv4-configured  kernel since 2.4,
+	    and the dnsmasq netlink code is now well tested, this 
+	    should work out fine. 
+
+	    Removed decayed build support for libc5 and Solaris.
+	    
+	    Removed pselect code: use a pipe for race-free signal
+	    handling instead, as this works everywhere.
+
+	    No longer enable the ISC leasefile reading code in the
+	    distributed sources. I doubt there are many people left
+	    using this 1.x compatibility code. Those that are will
+	    have to explicitly enable it in src/config.h.
+
+	    Don't send the "DHCP maximum message size" option, even if 
+	    requested. RFC2131 says this is a "MUST NOT".
+
+	    Support larger-than-minimum DHCP message. Dnsmasq is now
+	    happy to get larger than 576-byte DHCP messages, and will
+	    return large messages, if permitted by the "maximum
+	    message size" option of the message to which it is
+	    replying. There's now an arbitrary sanity limit of 16384
+	    bytes.
+
+	    Added --no-ping option. This fixes an RFC2131 "SHOULD".
+
+	    Building on the 2.27 MAC-address changes, allow clients to 
+	    provide no MAC address at all, relying on the client-id as
+	    a unique identifier. This should make things like DHCP for
+	    USB come easier.
+
+	    Fixed regression in netlink code under 2.2.x kernels which 
+	    occurred in 2.27. Erik Jan Tromp is the vintage kernel fan 
+	    who found this. P.S. It looks like this "netlink bind:
+	    permission denied" problem occured in kernels at least as
+	    late a 2.4.18. Good information from Alain Richoux.
+
+	    Added a warning when it's impossible to give a host its
+	    configured address because the address is leased
+	    elsewhere.  A sensible suggestion from Mircea Bardac.
+
+	    Added minimal support for RFC 3046 DHCP relay agent-id
+	    options. The DHCP server now echoes these back to the
+	    relay, as required by the RFC. Also, RFC 3527 link selection 
+	    sub-options are honoured.
+
+	    Set the process "dumpable" flag when running in debug
+	    mode: this makes getting core dumps from root processes
+	    much easier.
+	    
+	    Fixed one-byte buffer overflow which seems to only cause
+	    problems when dnsmasq is linked with uclibc. Thanks to
+	    Eric House and Eric Spakman for help in chasing this down.
+
+	    Tolerate configuration screwups which lead to the DHCP
+	    server attemping to allocate its own address to a
+	    client; eg setting the whole subnet range as a DHCP
+	    range. Addresses in use by the server are now excluded
+	    from use by clients.
+
+	    Did some thinking about HAVE_BROKEN_RTC mode, and made it
+	    much simpler and better. The key is to just keep lease
+	    lengths in the lease file. Since these normally never
+	    change, even as the lease is renewed, the lease file never
+	    needs to change except when machines arrive on the network
+	    or leave. This eliminates the code for timed writes, and
+	    reduces the amount of wear on a flash filesystem to the
+	    absolute minimum. Also re-did the basic time function in
+	    this mode to use the portable times(), rather than parsing
+	    /proc/uptime.
+
+	    Believe the source port number when replying to unicast 
+	    DHCP requests and DHCP requests via a relay, instead of always 
+            using the standard ports.  This will allow relays on 
+            non-standard ports and DHCPINFORM from unprivileged ports
+            to work. The source port sent by unconfigured clients is still 
+            ignored, since this may be unreliable. This means that a DHCP 
+            client must use the standard port to do full configuration.
+ 

FAQ

@@ -369,6 +369,12 @@ A: Yes, dynmaically allocated IP addresses are checked by sending an
    other DHCP requests during this time. To avoid dropping requests,
    the address probe may be skipped when dnsmasq is under heavy load.
 
+Q: I'm using dnsmasq on a machine with the Firestarter firewall, and
+   DHCP doesn't work. What's the problem?
+
+A: This a variant on the iptables problem. Explicit details on how to
+   proceed can be found at 
+   http://lists.thekelleys.org.uk/pipermail/dnsmasq-discuss/2005q3/000431.html
  
   
 

bld/Makefile

-# Uncomment this on Solaris.
-#LIBS = -lsocket -lnsl
-
 CFLAGS ?= -O2
 PKG_CONFIG ?= pkg-config
 
 
 OBJS = cache.o rfc1035.o util.o option.o forward.o isc.o network.o \
-       dnsmasq.o dhcp.o lease.o rfc2131.o netlink.o dbus.o
+       dnsmasq.o dhcp.o lease.o rfc2131.o netlink.o dbus.o bpf.o
 
 .c.o:
 	$(CC) $(CFLAGS) $(I18N) `../bld/pkg-wrapper $(PKG_CONFIG) --cflags dbus-1` $(RPM_OPT_FLAGS) -Wall -W -c $<

dnsmasq-rh.spec

@@ -5,7 +5,7 @@
 ###############################################################################
 
 Name: dnsmasq
-Version: 2.27
+Version: 2.28
 Release: 1
 License: GPL
 Group: System Environment/Daemons

dnsmasq-suse.spec

@@ -5,7 +5,7 @@
 ###############################################################################
 
 Name: dnsmasq
-Version: 2.27
+Version: 2.28
 Release: 1
 Copyright: GPL
 Group: Productivity/Networking/DNS/Servers

man/dnsmasq.8

@@ -525,6 +525,13 @@ with care, since each address allocated to a BOOTP client is leased
 forever, and therefore becomes permanently unavailable for re-use by
 other hosts.
 .TP
+.B \-5, --no-ping
+By default, the DHCP server will attempt to ensure that an address in
+not in use before allocating it to a host. It does this by sending an
+ICMP echo request (aka "ping") to the address in question. If it gets
+a reply, then the address must already be in use, and another is
+tried. This flag disables this check. Use with caution.
+.TP
 .B \-l, --dhcp-leasefile=<path>
 Use the specified file to store DHCP lease information. If this option
 is given but no dhcp-range option is given then dnsmasq version 1

rpm/dnsmasq-SuSE.patch

@@ -20,13 +20,4 @@
  #define IP6INTERFACES "/proc/net/if_inet6"
  #define UPTIME "/proc/uptime"
  #define DHCP_SERVER_PORT 67
-@@ -195,8 +195,8 @@
- 
- /* platform independent options. */
- #undef HAVE_BROKEN_RTC
--#define HAVE_ISC_READER
-+#undef HAVE_ISC_READER
- #undef HAVE_DBUS
- 
- #if defined(HAVE_BROKEN_RTC) && defined(HAVE_ISC_READER)
- #  error HAVE_ISC_READER is not compatible with HAVE_BROKEN_RTC
+

src/bpf.c

+/* dnsmasq is Copyright (c) 2000-2006 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.
+
+   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.
+*/
+
+#include "dnsmasq.h"
+
+#ifndef HAVE_LINUX_NETWORK
+
+#include <net/bpf.h>
+
+static struct iovec ifconf = {
+  .iov_base = NULL,
+  .iov_len = 0
+};
+
+static struct iovec ifreq = {
+  .iov_base = NULL,
+  .iov_len = 0
+};
+
+struct header {
+  struct ether_header ether; 
+  struct ip ip;
+  struct udphdr {
+    u16 uh_sport;               /* source port */
+    u16 uh_dport;               /* destination port */
+    u16 uh_ulen;                /* udp length */
+    u16 uh_sum;                 /* udp checksum */
+  } udp;
+};
+
+void init_bpf(struct daemon *daemon)
+{
+  int i = 0;
+
+  while (1) 
+    {
+      /* useful size which happens to be sufficient */
+      if (expand_buf(&ifreq, sizeof(struct ifreq)))
+	{
+	  sprintf(ifreq.iov_base, "/dev/bpf%d", i++);
+	  if ((daemon->dhcp_raw_fd = open(ifreq.iov_base, O_RDWR, 0)) != -1)
+	    return;
+	}
+      if (errno != EBUSY)
+	die(_("cannot create DHCP BPF socket: %s"), NULL);
+    }	     
+}
+
+void send_via_bpf(struct daemon *daemon, struct dhcp_packet *mess, size_t len,
+		  struct in_addr iface_addr, struct ifreq *ifr)
+{
+   /* Hairy stuff, packet either has to go to the
+      net broadcast or the destination can't reply to ARP yet,
+      but we do know the physical address. 
+      Build the packet by steam, and send directly, bypassing
+      the kernel IP stack */
+  
+  struct header header;
+  u32 i, sum;
+  struct iovec iov[2];
+
+  /* Only know how to do ethernet on *BSD */
+  if (mess->htype != ARPHRD_ETHER || mess->hlen != ETHER_ADDR_LEN)
+    {
+      syslog(LOG_WARNING, _("DHCP request for unsupported hardware type (%d) received on %s"), 
+	     mess->htype, ifr->ifr_name);
+      return;
+    }
+   
+  ifr->ifr_addr.sa_family = AF_LINK;
+  if (ioctl(daemon->dhcpfd, SIOCGIFADDR, ifr) < 0)
+    return;
+  
+  memcpy(header.ether.ether_shost, LLADDR((struct sockaddr_dl *)&ifr->ifr_addr), ETHER_ADDR_LEN);
+  header.ether.ether_type = htons(ETHERTYPE_IP);
+  
+  if (ntohs(mess->flags) & 0x8000)
+    {
+      memset(header.ether.ether_dhost, 255,  ETHER_ADDR_LEN);
+      header.ip.ip_dst.s_addr = INADDR_BROADCAST;
+    }
+  else
+    {
+      memcpy(header.ether.ether_dhost, mess->chaddr, ETHER_ADDR_LEN); 
+      header.ip.ip_dst.s_addr = mess->yiaddr.s_addr;
+    }
+  
+  header.ip.ip_p = IPPROTO_UDP;
+  header.ip.ip_src.s_addr = iface_addr.s_addr;
+  header.ip.ip_len = htons(sizeof(struct ip) + 
+			   sizeof(struct udphdr) +
+			   len) ;
+  header.ip.ip_hl = sizeof(struct ip) / 4;
+  header.ip.ip_v = IPVERSION;
+  header.ip.ip_tos = 0;
+  header.ip.ip_id = htons(0);
+  header.ip.ip_off = htons(0x4000); /* don't fragment */
+  header.ip.ip_ttl = IPDEFTTL;
+  header.ip.ip_sum = 0;
+  for (sum = 0, i = 0; i < sizeof(struct ip) / 2; i++)
+    sum += ((u16 *)&header.ip)[i];
+  while (sum>>16)
+    sum = (sum & 0xffff) + (sum >> 16);  
+  header.ip.ip_sum = (sum == 0xffff) ? sum : ~sum;
+  
+  header.udp.uh_sport = htons(DHCP_SERVER_PORT);
+  header.udp.uh_dport = htons(DHCP_CLIENT_PORT);
+  if (len & 1)
+    ((char *)mess)[len] = 0; /* for checksum, in case length is odd. */
+  header.udp.uh_sum = 0;
+  header.udp.uh_ulen = sum = htons(sizeof(struct udphdr) + len);
+  sum += htons(IPPROTO_UDP);
+  for (i = 0; i < 4; i++)
+    sum += ((u16 *)&header.ip.ip_src)[i];
+  for (i = 0; i < sizeof(struct udphdr)/2; i++)
+    sum += ((u16 *)&header.udp)[i];
+  for (i = 0; i < (len + 1) / 2; i++)
+    sum += ((u16 *)mess)[i];
+  while (sum>>16)
+    sum = (sum & 0xffff) + (sum >> 16);
+  header.udp.uh_sum = (sum == 0xffff) ? sum : ~sum;
+  
+  ioctl(daemon->dhcp_raw_fd, BIOCSETIF, ifr);
+  
+  iov[0].iov_base = &header;
+  iov[0].iov_len = sizeof(struct header);
+  iov[1].iov_base = mess;
+  iov[1].iov_len = len;
+  while (writev(daemon->dhcp_raw_fd, iov, 2) == -1 && retry_send());
+}
+
+int iface_enumerate(struct daemon *daemon, void *parm, int (*ipv4_callback)(), int (*ipv6_callback)())
+{
+  char *ptr;
+  struct ifreq *ifr, ifaux;
+  struct ifconf ifc;
+  int fd, errsav, ret = 0;
+  int lastlen = 0;
+  size_t len;
+  
+  if ((fd = socket(PF_INET, SOCK_DGRAM, 0)) == -1)
+    return 0;
+        
+  for (len = 0; ; len += 10*sizeof(struct ifreq))
+    {
+       if (!expand_buf(&ifconf, len))
+	 goto err;
+
+       ifc.ifc_len = len;
+       ifc.ifc_buf = ifconf.iov_base;
+
+       if (ioctl(fd, SIOCGIFCONF, &ifc) == -1)
+	 {
+	   if (errno != EINVAL || lastlen != 0)
+	     goto err;
+	 }
+       else
+	 {
+	   if (ifc.ifc_len == lastlen)
+	     break; /* got a big enough buffer now */
+	   lastlen = ifc.ifc_len;
+	 }
+     }
+  
+  for (ptr = ifc.ifc_buf; ptr < ifc.ifc_buf + ifc.ifc_len; ptr += len )
+    {
+      /* subsequent entries may not be aligned, so copy into
+	 an aligned buffer to avoid nasty complaints about 
+	 unaligned accesses. */
+#ifdef HAVE_SOCKADDR_SA_LEN
+      len = ((struct ifreq *)ptr)->ifr_addr.sa_len + IF_NAMESIZE;
+#else
+      len = sizeof(struct ifreq);
+#endif
+      if (!expand_buf(&ifreq, len))
+	goto err;
+
+      ifr = ifreq.iov_base;
+      memcpy(ifr, ptr, len);
+      
+      strncpy(ifaux.ifr_name, ifr->ifr_name, IF_NAMESIZE);
+           
+      if (ifr->ifr_addr.sa_family == AF_INET && ipv4_callback)
+	{
+	  struct in_addr addr, netmask, broadcast;
+	  if (ioctl(fd, SIOCGIFINDEX, &ifaux) == -1)
+	    continue;
+	  broadcast.s_addr = 0;
+	  addr = ((struct sockaddr_in *) &ifr->ifr_addr)->sin_addr;
+	  if (ioctl(fd, SIOCGIFNETMASK, ifr) == -1)
+	    continue;
+	  netmask = ((struct sockaddr_in *) &ifr->ifr_addr)->sin_addr;
+	  if (ioctl(fd, SIOCGIFBRDADDR, ifr) != -1)
+	    broadcast = ((struct sockaddr_in *) &ifr->ifr_addr)->sin_addr; 
+	  if (!((*ipv4_callback)(daemon, addr, (int)ifaux.ifr_index, netmask, broadcast, parm)))
+	    goto err;
+	}
+#ifdef HAVE_IPV6
+      else if (ifr->ifr_addr.sa_family == AF_INET6 && ipv6_callback)
+	{
+	  struct in6_addr *addr = &((struct sockaddr_in6 *)&ifr->ifr_addr)->sin6_addr;
+	  /* voodoo to clear interface field in address */
+	  if (!(daemon->options & OPT_NOWILD) && IN6_IS_ADDR_LINKLOCAL(addr))
+	    {
+	      addr->s6_addr[2] = 0;
+	      addr->s6_addr[3] = 0;
+	    }
+	  if (ioctl(fd, SIOCGIFINDEX, &ifaux) == -1)
+	    continue;
+	  if (!((*ipv6_callback)(daemon, addr,
+				 (int)((struct sockaddr_in6 *)&ifr->ifr_addr)->sin6_scope_id,
+				 (int)ifaux.ifr_index,
+				 parm)))
+	    goto err;
+	}
+#endif
+    }
+  
+  ret = 1;
+
+ err:
+  errsav = errno;
+  close(fd);  
+  errno = errsav;
+
+  return ret;
+}
+
+#endif

src/cache.c

@@ -18,6 +18,7 @@ static int cache_inserted, cache_live_freed, insert_error;
 static union bigname *big_free;
 static int bignames_left, log_queries, cache_size, hash_size;
 static int uid;
+static char *addrbuff;
 
 static void cache_free(struct crec *crecp);
 static void cache_unlink(struct crec *crecp);
@@ -29,7 +30,11 @@ void cache_init(int size, int logq)
   struct crec *crecp;
   int i;
 
-  log_queries = logq;
+  if ((log_queries = logq))
+    addrbuff = safe_malloc(ADDRSTRLEN);
+  else
+    addrbuff = NULL;
+      
   cache_head = cache_tail = NULL;
   dhcp_inuse = dhcp_spare = NULL;
   new_chain = NULL;
@@ -762,17 +767,17 @@ void cache_add_dhcp_entry(struct daemon *daemon, char *host_name,
 
 
 
-void dump_cache(struct daemon *daemon)
+void dump_cache(struct daemon *daemon, time_t now)
 {
-  syslog(LOG_INFO, _("cache size %d, %d/%d cache insertions re-used unexpired cache entries."), 
-	 daemon->cachesize, cache_live_freed, cache_inserted); 
+  syslog(LOG_INFO, _("time %lu, cache size %d, %d/%d cache insertions re-used unexpired cache entries."), 
+	 (unsigned long)now, daemon->cachesize, cache_live_freed, cache_inserted); 
   
-  if (daemon->options & (OPT_DEBUG | OPT_LOG))
+  if ((daemon->options & (OPT_DEBUG | OPT_LOG)) &&
+      (addrbuff || (addrbuff = malloc(ADDRSTRLEN))))
     {
       struct crec *cache ;
-      char addrbuff[ADDRSTRLEN];
       int i;
-      syslog(LOG_DEBUG, "Host                                     Address                        Flags     Expires\n");
+      syslog(LOG_DEBUG, "Host                                     Address                        Flags     Expires");
     
       for (i=0; i<hash_size; i++)
 	for (cache = hash_table[i]; cache; cache = cache->hash_next)
@@ -797,7 +802,7 @@ void dump_cache(struct daemon *daemon)
 #endif
 	    syslog(LOG_DEBUG, 
 #ifdef HAVE_BROKEN_RTC
-		   "%-40.40s %-30.30s %s%s%s%s%s%s%s%s%s%s  %ld\n",
+		   "%-40.40s %-30.30s %s%s%s%s%s%s%s%s%s%s  %lu",
 #else
 		   "%-40.40s %-30.30s %s%s%s%s%s%s%s%s%s%s  %s",
 #endif
@@ -813,7 +818,7 @@ void dump_cache(struct daemon *daemon)
 		   cache->flags & F_NXDOMAIN ? "X" : " ",
 		   cache->flags & F_HOSTS ? "H" : " ",
 #ifdef HAVE_BROKEN_RTC
-		   cache->flags & F_IMMORTAL ? 0: (unsigned long)cache->ttd
+		   cache->flags & F_IMMORTAL ? 0: (unsigned long)(cache->ttd - now)
 #else
 	           cache->flags & F_IMMORTAL ? "\n" : ctime(&(cache->ttd)) 
 #endif
@@ -844,8 +849,7 @@ void log_query(unsigned short flags, char *name, struct all_addr *addr,
   char *source;
   char *verb = "is";
   char types[20];
-  char addrbuff[ADDRSTRLEN];
-
+  
   if (!log_queries)
     return;
   

src/dbus.c

@@ -113,13 +113,14 @@ static void dbus_read_servers(struct daemon *daemon, DBusMessage *message)
 #else
 	  if (i == sizeof(struct in6_addr)-1)
 	    {
-	      memcpy(&addr.in6.sin6_addr, p, sizeof(struct in6_addr));
+	      memcpy(&addr.in6.sin6_addr, p, sizeof(addr.in6));
 #ifdef HAVE_SOCKADDR_SA_LEN
-              source_addr.in6.sin6_len = addr.in6.sin6_len = sizeof(struct sockaddr_in6);
+              source_addr.in6.sin6_len = addr.in6.sin6_len = sizeof(addr.in6);
 #endif
               source_addr.in6.sin6_family = addr.in6.sin6_family = AF_INET6;
               addr.in6.sin6_port = htons(NAMESERVER_PORT);
-              source_addr.in6.sin6_flowinfo = addr.in6.sin6_flowinfo = htonl(0);
+              source_addr.in6.sin6_flowinfo = addr.in6.sin6_flowinfo = 0;
+	      source_addr.in6.sin6_scope_id = addr.in6.sin6_scope_id = 0;
               source_addr.in6.sin6_addr = in6addr_any;
               source_addr.in6.sin6_port = htons(daemon->query_port);
 	      skip = 0;
@@ -211,14 +212,14 @@ static void dbus_read_servers(struct daemon *daemon, DBusMessage *message)
 	  free(serv);
 	}
       else 
-	    up = &serv->next;
+	up = &serv->next;
     }
 
 }
 
-DBusHandlerResult message_handler (DBusConnection *connection, 
-				   DBusMessage *message, 
-				   void *user_data)
+DBusHandlerResult message_handler(DBusConnection *connection, 
+				  DBusMessage *message, 
+				  void *user_data)
 {
   char *method = (char *)dbus_message_get_member(message);
   struct daemon *daemon = (struct daemon *)user_data;
@@ -239,7 +240,7 @@ DBusHandlerResult message_handler (DBusConnection *connection,
       check_servers(daemon);
     }
   else if (strcmp(method, "ClearCache") == 0)
-    clear_cache_and_reload(daemon, dnsmasq_time(daemon->uptime_fd));
+    clear_cache_and_reload(daemon);
   else
     return (DBUS_HANDLER_RESULT_NOT_YET_HANDLED);
   

src/isc.c

@@ -17,6 +17,8 @@
 
 #ifdef HAVE_ISC_READER
 
+#define MAXTOK 50
+
 struct isc_lease {
   char *name, *fqdn;
   time_t expires;