Add --conf-script

The circumstances under which actions occur depending on
configuration is now controlled only by newaddress() in network.c

CHANGELOG

@@ -39,6 +39,16 @@ version 2.87
 	a local NODATA answer. The pre-2.86 behaviour is still available,
 	by configuring --address=/example.com/1.2.3.4 --local=/example.com/
 
+        Fix problem with binding DHCP sockets to an individual interface.
+	Despite the fact that the system call tales the interface _name_ as
+	a parameter, it actually, binds the socket to interface _index_.
+	Deleting the interface and creating a new one with the same name
+	leaves the socket bound to the old index. (Creating new sockets
+	always allocates a fresh index, they are not reused). We now
+	take this behaviour into account and keep up with changing indexes.
+
+	Add --conf-script configuration option.
+
 	
 version 2.86
 	Handle DHCPREBIND requests in the DHCPv6 server code.

man/dnsmasq.8

@@ -777,7 +777,7 @@ will add 1.2.3.0/24 for both IPv4 and IPv6 requestors.
 .TP
 .B --strip-subnet
 Remove any subnet address already present in a downstream query before forwarding it upstream. If --add-subnet is set this also
-ensures that any downstream-provided subnet is replaced by the one added by dnsmasq. Otherwise, dnsmaaq will NOT replace an
+ensures that any downstream-provided subnet is replaced by the one added by dnsmasq. Otherwise, dnsmasq will NOT replace an
 existing subnet in the query.
 .TP
 .B --umbrella[=[deviceid:<deviceid>][,orgid:<orgid>][,assetid:<id>]]
@@ -2141,6 +2141,23 @@ A special case of
 which differs in two respects. Firstly, only \fB--server\fP and \fB--rev-server\fP are allowed
 in the configuration file included. Secondly, the file is re-read and the configuration
 therein is updated when dnsmasq receives SIGHUP.
+.TP
+.B \--conf-script=<file>[ <arg]
+Execute <file>, and treat what it emits to stdout as the contents of a configuration file.
+If the script exits with a non-zero exit code, dnsmasq treats this as a fatal error.
+The script can be passed arguments, space seperated from the filename and each other so, for instance
+.B --conf-dir="/etc/dnsmasq-uncompress-ads /share/ads-domains.gz"
+
+with /etc/dnsmasq-uncompress-ads containing 
+
+set -e
+
+zcat ${1} | sed -e "s:^:address=/:" -e "s:$:/:" 
+
+exit 0
+
+and /share/ads-domains.gz containing a compressed
+list of ad server domains will save disk space with large ad-server blocklists.
 .SH CONFIG FILE
 At startup, dnsmasq reads
 .I /etc/dnsmasq.conf,
@@ -2537,7 +2554,9 @@ file/directory, permissions).
 5 - Other miscellaneous problem.
 .PP
 11 or greater - a non zero return code was received from the
-lease-script process "init" call. The exit code from dnsmasq is the
+lease-script process "init" call or a
+.B \--conf-script
+file. The exit code from dnsmasq is the
 script's exit code with 10 added. 
 
 .SH LIMITS

src/dhcp-common.c

@@ -566,12 +566,16 @@ char *whichdevice(void)
       }
 
   if (found)
-    return found->name;
-
+    {
+      char *ret = safe_malloc(strlen(found->name)+1);
+      strcpy(ret, found->name);
+      return ret;
+    }
+  
   return NULL;
 }
  
-void  bindtodevice(char *device, int fd)
+static int bindtodevice(char *device, int fd)
 {
   size_t len = strlen(device)+1;
   if (len > IFNAMSIZ)
@@ -579,7 +583,33 @@ void  bindtodevice(char *device, int fd)
   /* only allowed by root. */
   if (setsockopt(fd, SOL_SOCKET, SO_BINDTODEVICE, device, len) == -1 &&
       errno != EPERM)
-    die(_("failed to set SO_BINDTODEVICE on DHCP socket: %s"), NULL, EC_BADNET);
+    return 2;
+  
+  return 1;
+}
+
+int bind_dhcp_devices(char *bound_device)
+{
+  int ret = 0;
+
+  if (bound_device)
+    {
+      if (daemon->dhcp)
+	{
+	  if (!daemon->relay4)
+	    ret |= bindtodevice(bound_device, daemon->dhcpfd);
+	  
+	  if (daemon->enable_pxe && daemon->pxefd != -1)
+	    ret |= bindtodevice(bound_device, daemon->pxefd);
+	}
+      
+#if defined(HAVE_DHCP6)
+      if (daemon->doing_dhcp6 && !daemon->relay6)
+	ret |= bindtodevice(bound_device, daemon->dhcp6fd);
+#endif
+    }
+  
+  return ret;
 }
 #endif
 

src/dhcp.c

@@ -458,9 +458,12 @@ void dhcp_packet(time_t now, int pxe_fd)
   else 
     {
 #ifdef HAVE_DUMPFILE
-      dest.sin_addr.s_addr = (ntohs(mess->flags) & 0x8000) ? INADDR_BROADCAST : mess->yiaddr;
+      if (ntohs(mess->flags) & 0x8000)
+        dest.sin_addr.s_addr = INADDR_BROADCAST;
+      else
+        dest.sin_addr = mess->yiaddr;
       dest.sin_port = htons(daemon->dhcp_client_port);
-
+      
       dump_packet(DUMP_DHCP, (void *)iov.iov_base, iov.iov_len, NULL,
 		  (union mysockaddr *)&dest, daemon->dhcp_server_port);
 #endif

src/dnsmasq.c

@@ -387,28 +387,9 @@ int main (int argc, char **argv)
 #if defined(HAVE_LINUX_NETWORK) && defined(HAVE_DHCP)
       /* after enumerate_interfaces()  */
       bound_device = whichdevice();
-      
-      if (daemon->dhcp)
-	{
-	  if (!daemon->relay4 && bound_device)
-	    {
-	      bindtodevice(bound_device, daemon->dhcpfd);
-	      did_bind = 1;
-	    }
-	  if (daemon->enable_pxe && bound_device && daemon->pxefd != -1)
-	    {
-	      bindtodevice(bound_device, daemon->pxefd);
-	      did_bind = 1;
-	    }
-	}
-#endif
 
-#if defined(HAVE_LINUX_NETWORK) && defined(HAVE_DHCP6)
-      if (daemon->doing_dhcp6 && !daemon->relay6 && bound_device)
-	{
-	  bindtodevice(bound_device, daemon->dhcp6fd);
-	  did_bind = 1;
-	}
+      if ((did_bind = bind_dhcp_devices(bound_device)) & 2)
+	die(_("failed to set SO_BINDTODEVICE on DHCP socket: %s"), NULL, EC_BADNET);	
 #endif
     }
   else 
@@ -1100,6 +1081,17 @@ int main (int argc, char **argv)
 #endif
       
 #ifdef HAVE_DHCP
+#  if defined(HAVE_LINUX_NETWORK)
+      if (bind_dhcp_devices(bound_device) & 2)
+	{
+	  static int warned = 0;
+	  if (!warned)
+	    {
+	      my_syslog(LOG_ERR, _("error binding DHCP socket to device %s"), bound_device);
+	      warned = 1;
+	    }
+	}
+# endif
       if (daemon->dhcp || daemon->relay4)
 	{
 	  poll_listen(daemon->dhcpfd, POLLIN);

src/dnsmasq.h

@@ -1715,7 +1715,7 @@ struct dhcp_config *find_config(struct dhcp_config *configs,
 int config_has_mac(struct dhcp_config *config, unsigned char *hwaddr, int len, int type);
 #ifdef HAVE_LINUX_NETWORK
 char *whichdevice(void);
-void bindtodevice(char *device, int fd);
+int bind_dhcp_devices(char *bound_device);
 #endif
 #  ifdef HAVE_DHCP6
 void display_opts6(void);

src/netlink.c

@@ -66,17 +66,10 @@ char *netlink_init(void)
   addr.nl_pad = 0;
   addr.nl_pid = 0; /* autobind */
   addr.nl_groups = RTMGRP_IPV4_ROUTE;
-  if (option_bool(OPT_CLEVERBIND))
-    addr.nl_groups |= RTMGRP_IPV4_IFADDR;  
+  addr.nl_groups |= RTMGRP_IPV4_IFADDR;  
   addr.nl_groups |= RTMGRP_IPV6_ROUTE;
-  if (option_bool(OPT_CLEVERBIND))
-    addr.nl_groups |= RTMGRP_IPV6_IFADDR;
+  addr.nl_groups |= RTMGRP_IPV6_IFADDR;
 
-#ifdef HAVE_DHCP6
-  if (daemon->doing_ra || daemon->doing_dhcp6)
-    addr.nl_groups |= RTMGRP_IPV6_IFADDR;
-#endif
-  
   /* May not be able to have permission to set multicast groups don't die in that case */
   if ((daemon->netlinkfd = socket(AF_NETLINK, SOCK_RAW, NETLINK_ROUTE)) != -1)
     {

src/network.c

@@ -114,13 +114,8 @@ int iface_check(int family, union all_addr *addr, char *name, int *auth)
   struct iname *tmp;
   int ret = 1, match_addr = 0;
 
-  /* Note: have to check all and not bail out early, so that we set the
-     "used" flags.
-
-     May be called with family == AF_LOCALto check interface by name only. */
-  
-  if (auth)
-    *auth = 0;
+  /* Note: have to check all and not bail out early, so that we set the "used" flags.
+     May be called with family == AF_LOCAL to check interface by name only. */
   
   if (daemon->if_names || daemon->if_addrs)
     {
@@ -149,25 +144,29 @@ int iface_check(int family, union all_addr *addr, char *name, int *auth)
       if (tmp->name && wildcard_match(tmp->name, name))
 	ret = 0;
     
-
-  for (tmp = daemon->authinterface; tmp; tmp = tmp->next)
-    if (tmp->name)
-      {
-	if (strcmp(tmp->name, name) == 0 &&
-	    (tmp->addr.sa.sa_family == 0 || tmp->addr.sa.sa_family == family))
-	  break;
-      }
-    else if (addr && tmp->addr.sa.sa_family == AF_INET && family == AF_INET &&
-	     tmp->addr.in.sin_addr.s_addr == addr->addr4.s_addr)
-      break;
-    else if (addr && tmp->addr.sa.sa_family == AF_INET6 && family == AF_INET6 &&
-	     IN6_ARE_ADDR_EQUAL(&tmp->addr.in6.sin6_addr, &addr->addr6))
-      break;
-
-  if (tmp && auth) 
+  if (auth)
     {
-      *auth = 1;
-      ret = 1;
+      *auth = 0;
+
+      for (tmp = daemon->authinterface; tmp; tmp = tmp->next)
+	if (tmp->name)
+	  {
+	    if (strcmp(tmp->name, name) == 0 &&
+		(tmp->addr.sa.sa_family == 0 || tmp->addr.sa.sa_family == family))
+	      break;
+	  }
+	else if (addr && tmp->addr.sa.sa_family == AF_INET && family == AF_INET &&
+		 tmp->addr.in.sin_addr.s_addr == addr->addr4.s_addr)
+	  break;
+	else if (addr && tmp->addr.sa.sa_family == AF_INET6 && family == AF_INET6 &&
+		 IN6_ARE_ADDR_EQUAL(&tmp->addr.in6.sin6_addr, &addr->addr6))
+	  break;
+      
+      if (tmp) 
+	{
+	  *auth = 1;
+	  ret = 1;
+	}
     }
 
   return ret; 

src/option.c

@@ -179,6 +179,8 @@ struct myoption {
 #define LOPT_FILTER_AAAA   370
 #define LOPT_STRIP_SBNET   371
 #define LOPT_STRIP_MAC     372
+#define LOPT_CONF_OPT      373
+#define LOPT_CONF_SCRIPT   374
 
 #ifdef HAVE_GETOPT_LONG
 static const struct option opts[] =  
@@ -225,6 +227,7 @@ static const struct myoption opts[] =
     { "local", 1, 0, LOPT_LOCAL },
     { "address", 1, 0, 'A' },
     { "conf-file", 2, 0, 'C' },
+    { "conf-script", 1, 0, LOPT_CONF_SCRIPT },
     { "no-resolv", 0, 0, 'R' },
     { "expand-hosts", 0, 0, 'E' },
     { "localmx", 0, 0, 'L' },
@@ -467,6 +470,7 @@ static struct {
   { LOPT_SCRIPTUSR, ARG_ONE, "<username>", gettext_noop("Run lease-change scripts as this user."), NULL },
   { LOPT_SCRIPT_ARP, OPT_SCRIPT_ARP, NULL, gettext_noop("Call dhcp-script with changes to local ARP table."), NULL },
   { '7', ARG_DUP, "<path>", gettext_noop("Read configuration from all the files in this directory."), NULL },
+  { LOPT_CONF_SCRIPT, ARG_DUP, "<path>", gettext_noop("Execute file and read configuration from stdin."), NULL },
   { '8', ARG_ONE, "<facility>|<file>", gettext_noop("Log to this syslog facility or file. (defaults to DAEMON)"), NULL },
   { '9', OPT_LEASE_RO, NULL, gettext_noop("Do not use leasefile."), NULL },
   { '0', ARG_ONE, "<integer>", gettext_noop("Maximum number of concurrent DNS queries. (defaults to %s)"), "!" }, 
@@ -1810,6 +1814,17 @@ static int one_opt(int option, char *arg, char *errstr, char *gen_err, int comma
 	break;
       }
 
+    case LOPT_CONF_SCRIPT: /* --conf-script */
+      {
+	char *file = opt_string_alloc(arg);
+	if (file)
+	  {
+	    one_file(file, LOPT_CONF_SCRIPT);
+	    free(file);
+	  }
+	break;
+      }
+
     case '7': /* --conf-dir */	      
       {
 	DIR *dir_stream;
@@ -2537,13 +2552,13 @@ static int one_opt(int option, char *arg, char *errstr, char *gen_err, int comma
 	      arg += 9;
 	      if (strlen(arg) != 16)
 		ret_err(gen_err);
-         
+	      
 	      for (p = arg; *p; p++)
 		if (!isxdigit((int)*p))
 		  ret_err(gen_err);
-          
+	      
 	      set_option_bool(OPT_UMBRELLA_DEVID);
-	   	      
+	      
 	      for (i = 0; i < (int)sizeof(daemon->umbrella_device); i++, arg+=2)
 		{
 		  memcpy(word, &(arg[0]), 2);
@@ -2555,13 +2570,13 @@ static int one_opt(int option, char *arg, char *errstr, char *gen_err, int comma
 	      if (!strtoul_check(arg+6, &daemon->umbrella_org))
 		ret_err(gen_err);
 	    }
-        else if (strstr(arg, "assetid:"))
-	  {
-	    if (!strtoul_check(arg+8, &daemon->umbrella_asset))
-	      ret_err(gen_err);
-	  }
-	else
-	  ret_err(gen_err);
+	  else if (strstr(arg, "assetid:"))
+	    {
+	      if (!strtoul_check(arg+8, &daemon->umbrella_asset))
+		ret_err(gen_err);
+	    }
+	  else
+	    ret_err(gen_err);
 	  
 	  arg = comma;
 	}
@@ -4966,11 +4981,19 @@ static void read_file(char *file, FILE *f, int hard_opt)
   
   while (fgets(buff, MAXDNAME, f))
     {
-      int white, i;
-      volatile int option = (hard_opt == LOPT_REV_SERV) ? 0 : hard_opt;
+      int white, i, script = 0;
+      volatile int option;
       char *errmess, *p, *arg, *start;
       size_t len;
 
+      if (hard_opt == LOPT_CONF_SCRIPT)
+	{
+	  hard_opt = 0;
+	  script = 1;
+	}
+      
+      option = (hard_opt == LOPT_REV_SERV) ? 0 : hard_opt;
+ 
       /* Memory allocation failure longjmps here if mem_recover == 1 */ 
       if (option != 0 || hard_opt == LOPT_REV_SERV)
 	{
@@ -5084,7 +5107,11 @@ static void read_file(char *file, FILE *f, int hard_opt)
 	  
       if (errmess || !one_opt(option, arg, daemon->namebuff, _("error"), 0, hard_opt == LOPT_REV_SERV))
 	{
-	  sprintf(daemon->namebuff + strlen(daemon->namebuff), _(" at line %d of %s"), lineno, file);
+	  if (script)
+	    sprintf(daemon->namebuff + strlen(daemon->namebuff), _(" in output from %s"), file);
+	  else
+	    sprintf(daemon->namebuff + strlen(daemon->namebuff), _(" at line %d of %s"), lineno, file);
+	  
 	  if (hard_opt != 0)
 	    my_syslog(LOG_ERR, "%s", daemon->namebuff);
 	  else
@@ -5093,7 +5120,6 @@ static void read_file(char *file, FILE *f, int hard_opt)
     }
 
   mem_recover = 0;
-  fclose(f);
 }
 
 #if defined(HAVE_DHCP) && defined(HAVE_INOTIFY)
@@ -5113,7 +5139,7 @@ int option_read_dynfile(char *file, int flags)
 static int one_file(char *file, int hard_opt)
 {
   FILE *f;
-  int nofile_ok = 0;
+  int nofile_ok = 0, do_popen = 0;
   static int read_stdin = 0;
   static struct fileread {
     dev_t dev;
@@ -5121,13 +5147,13 @@ static int one_file(char *file, int hard_opt)
     struct fileread *next;
   } *filesread = NULL;
   
-  if (hard_opt == '7')
+  if (hard_opt == LOPT_CONF_OPT)
     {
       /* default conf-file reading */
       hard_opt = 0;
       nofile_ok = 1;
     }
-
+  
   if (hard_opt == 0 && strcmp(file, "-") == 0)
     {
       if (read_stdin == 1)
@@ -5141,6 +5167,12 @@ static int one_file(char *file, int hard_opt)
       /* ignore repeated files. */
       struct stat statbuf;
     
+      if (hard_opt == LOPT_CONF_SCRIPT)
+	{
+	  hard_opt = 0;
+	  do_popen = 1;
+	}
+      
       if (hard_opt == 0 && stat(file, &statbuf) == 0)
 	{
 	  struct fileread *r;
@@ -5155,8 +5187,13 @@ static int one_file(char *file, int hard_opt)
 	  r->dev = statbuf.st_dev;
 	  r->ino = statbuf.st_ino;
 	}
-      
-      if (!(f = fopen(file, "r")))
+
+      if (do_popen)
+	{
+	  if (!(f = popen(file, "r")))
+	    die(_("cannot execute %s: %s"), file, EC_FILE);
+	}
+      else if (!(f = fopen(file, "r")))
 	{   
 	  if (errno == ENOENT && nofile_ok)
 	    return 1; /* No conffile, all done. */
@@ -5174,7 +5211,21 @@ static int one_file(char *file, int hard_opt)
 	} 
     }
   
-  read_file(file, f, hard_opt);
+  read_file(file, f, do_popen ? LOPT_CONF_SCRIPT : hard_opt);
+
+  if (do_popen)
+    {
+      int rc;
+
+      if ((rc = pclose(f)) == -1)
+	die(_("error executing %s: %s"), file, EC_MISC);
+
+      if (rc != 0)
+	die(_("%s returns non-zero error code"), file, rc+10);
+    }
+  else
+    fclose(f);
+	
   return 1;
 }
 
@@ -5315,6 +5366,7 @@ void read_servers_file(void)
   
   mark_servers(SERV_FROM_FILE);
   read_file(daemon->servers_file, f, LOPT_REV_SERV);
+  fclose(f);
   cleanup_servers();
   check_servers(0);
 }
@@ -5540,7 +5592,7 @@ void read_opts(int argc, char **argv, char *compile_opts)
       free(conffile);
     }
   else
-    one_file(CONFFILE, '7');
+    one_file(CONFFILE, LOPT_CONF_OPT);
 
   /* port might not be known when the address is parsed - fill in here */
   if (daemon->servers)