ares 1.1.1 with collected applied patches

1 files changed, 776 insertions, 0 deletions

diff --git a/ares/ares_init.c b/ares/ares_init.c
new file mode 100644
index 000000000..086bdb6a1
--- /dev/null
+++ b/ares/ares_init.c
@@ -0,0 +1,776 @@
+/* Copyright 1998 by the Massachusetts Institute of Technology.
+ *
+ * Permission to use, copy, modify, and distribute this
+ * software and its documentation for any purpose and without
+ * fee is hereby granted, provided that the above copyright
+ * notice appear in all copies and that both that copyright
+ * notice and this permission notice appear in supporting
+ * documentation, and that the name of M.I.T. not be used in
+ * advertising or publicity pertaining to distribution of the
+ * software without specific, written prior permission.
+ * M.I.T. makes no representations about the suitability of
+ * this software for any purpose.  It is provided "as is"
+ * without express or implied warranty.
+ */
+
+static const char rcsid[] = "$Id$";
+
+#include <sys/types.h>
+
+#ifdef WIN32
+#include "nameser.h"
+#else
+#include <sys/param.h>
+#include <sys/time.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <netdb.h>
+#include <arpa/nameser.h>
+#include <unistd.h>
+#endif
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <ctype.h>
+#include <time.h>
+#include <errno.h>
+#include "ares.h"
+#include "ares_private.h"
+
+static int init_by_options(ares_channel channel, struct ares_options *options,
+			   int optmask);
+static int init_by_environment(ares_channel channel);
+static int init_by_resolv_conf(ares_channel channel);
+static int init_by_defaults(ares_channel channel);
+static int config_domain(ares_channel channel, char *str);
+static int config_lookup(ares_channel channel, const char *str);
+static int config_nameserver(struct server_state **servers, int *nservers,
+			     const char *str);
+static int config_sortlist(struct apattern **sortlist, int *nsort,
+			   const char *str);
+static int set_search(ares_channel channel, const char *str);
+static int set_options(ares_channel channel, const char *str);
+static char *try_config(char *s, char *opt);
+static const char *try_option(const char *p, const char *q, const char *opt);
+static int ip_addr(const char *s, int len, struct in_addr *addr);
+static void natural_mask(struct apattern *pat);
+
+int ares_init(ares_channel *channelptr)
+{
+  return ares_init_options(channelptr, NULL, 0);
+}
+
+int ares_init_options(ares_channel *channelptr, struct ares_options *options,
+		      int optmask)
+{
+  ares_channel channel;
+  int i, status;
+  struct server_state *server;
+  struct timeval tv;
+
+  channel = malloc(sizeof(struct ares_channeldata));
+  if (!channel)
+    return ARES_ENOMEM;
+
+  /* Set everything to distinguished values so we know they haven't
+   * been set yet.
+   */
+  channel->flags = -1;
+  channel->timeout = -1;
+  channel->tries = -1;
+  channel->ndots = -1;
+  channel->udp_port = -1;
+  channel->tcp_port = -1;
+  channel->nservers = -1;
+  channel->ndomains = -1;
+  channel->nsort = -1;
+  channel->lookups = NULL;
+  channel->queries = NULL;
+
+  /* Initialize configuration by each of the four sources, from highest
+   * precedence to lowest.
+   */
+  status = init_by_options(channel, options, optmask);
+  if (status == ARES_SUCCESS)
+    status = init_by_environment(channel);
+  if (status == ARES_SUCCESS)
+    status = init_by_resolv_conf(channel);
+  if (status == ARES_SUCCESS)
+    status = init_by_defaults(channel);
+  if (status != ARES_SUCCESS)
+    {
+      /* Something failed; clean up memory we may have allocated. */
+      if (channel->nservers != -1)
+	free(channel->servers);
+      if (channel->ndomains != -1)
+	{
+	  for (i = 0; i < channel->ndomains; i++)
+	    free(channel->domains[i]);
+	  free(channel->domains);
+	}
+      if (channel->nsort != -1)
+	free(channel->sortlist);
+      free(channel->lookups);
+      free(channel);
+      return status;
+    }
+
+  /* Trim to one server if ARES_FLAG_PRIMARY is set. */
+  if ((channel->flags & ARES_FLAG_PRIMARY) && channel->nservers > 1)
+    channel->nservers = 1;
+
+  /* Initialize server states. */
+  for (i = 0; i < channel->nservers; i++)
+    {
+      server = &channel->servers[i];
+      server->udp_socket = -1;
+      server->tcp_socket = -1;
+      server->tcp_lenbuf_pos = 0;
+      server->tcp_buffer = NULL;
+      server->qhead = NULL;
+      server->qtail = NULL;
+    }
+
+  /* Choose a somewhat random query ID.  The main point is to avoid
+   * collisions with stale queries.  An attacker trying to spoof a DNS
+   * answer also has to guess the query ID, but it's only a 16-bit
+   * field, so there's not much to be done about that.
+   */
+  gettimeofday(&tv, NULL);
+  channel->next_id = (tv.tv_sec ^ tv.tv_usec ^ getpid()) & 0xffff;
+
+  channel->queries = NULL;
+
+  *channelptr = channel;
+  return ARES_SUCCESS;
+}
+
+static int init_by_options(ares_channel channel, struct ares_options *options,
+			   int optmask)
+{
+  int i;
+
+  /* Easy stuff. */
+  if ((optmask & ARES_OPT_FLAGS) && channel->flags == -1)
+    channel->flags = options->flags;
+  if ((optmask & ARES_OPT_TIMEOUT) && channel->timeout == -1)
+    channel->timeout = options->timeout;
+  if ((optmask & ARES_OPT_TRIES) && channel->tries == -1)
+    channel->tries = options->tries;
+  if ((optmask & ARES_OPT_NDOTS) && channel->ndots == -1)
+    channel->ndots = options->ndots;
+  if ((optmask & ARES_OPT_UDP_PORT) && channel->udp_port == -1)
+    channel->udp_port = options->udp_port;
+  if ((optmask & ARES_OPT_TCP_PORT) && channel->tcp_port == -1)
+    channel->tcp_port = options->tcp_port;
+
+  /* Copy the servers, if given. */
+  if ((optmask & ARES_OPT_SERVERS) && channel->nservers == -1)
+    {
+      channel->servers =
+	malloc(options->nservers * sizeof(struct server_state));
+      if (!channel->servers && options->nservers != 0)
+	return ARES_ENOMEM;
+      for (i = 0; i < options->nservers; i++)
+	channel->servers[i].addr = options->servers[i];
+      channel->nservers = options->nservers;
+    }
+
+  /* Copy the domains, if given.  Keep channel->ndomains consistent so
+   * we can clean up in case of error.
+   */
+  if ((optmask & ARES_OPT_DOMAINS) && channel->ndomains == -1)
+    {
+      channel->domains = malloc(options->ndomains * sizeof(char *));
+      if (!channel->domains && options->ndomains != 0)
+	return ARES_ENOMEM;
+      for (i = 0; i < options->ndomains; i++)
+	{
+	  channel->ndomains = i;
+	  channel->domains[i] = strdup(options->domains[i]);
+	  if (!channel->domains[i])
+	    return ARES_ENOMEM;
+	}
+      channel->ndomains = options->ndomains;
+    }
+
+  /* Set lookups, if given. */
+  if ((optmask & ARES_OPT_LOOKUPS) && !channel->lookups)
+    {
+      channel->lookups = strdup(options->lookups);
+      if (!channel->lookups)
+	return ARES_ENOMEM;
+    }
+
+  return ARES_SUCCESS;
+}
+
+static int init_by_environment(ares_channel channel)
+{
+  const char *localdomain, *res_options;
+  int status;
+
+  localdomain = getenv("LOCALDOMAIN");
+  if (localdomain && channel->ndomains == -1)
+    {
+      status = set_search(channel, localdomain);
+      if (status != ARES_SUCCESS)
+	return status;
+    }
+
+  res_options = getenv("RES_OPTIONS");
+  if (res_options)
+    {
+      status = set_options(channel, res_options);
+      if (status != ARES_SUCCESS)
+	return status;
+    }
+
+  return ARES_SUCCESS;
+}
+#ifdef WIN32
+static int get_res_size_nt(HKEY hKey, char *subkey, int *size)
+{
+	return RegQueryValueEx(hKey, subkey, 0, NULL, NULL, size);
+}
+
+/* Warning: returns a dynamically allocated buffer, the user MUST
+ * use free() if the function returns 1
+ */
+static int get_res_nt(HKEY hKey, char *subkey, char **obuf)
+{
+	/* Test for the size we need */
+	int size = 0;
+	int result;
+	result = RegQueryValueEx(hKey, subkey, 0, NULL, NULL, &size);
+	if ((result != ERROR_SUCCESS && result != ERROR_MORE_DATA) || !size)
+		return 0;
+	*obuf = malloc(size+1);
+
+	if (RegQueryValueEx(hKey, subkey, 0, NULL, *obuf, &size) != ERROR_SUCCESS)
+	{
+		free(*obuf);
+		return 0;
+	}
+	if (size == 1)
+	{
+		free(*obuf);
+		return 0;
+	}
+	return 1;
+}
+
+static int get_res_interfaces_nt(HKEY hKey, char *subkey, char **obuf)
+{
+	char enumbuf[39]; /* GUIDs are 38 chars + 1 for NULL */
+	int enum_size = 39;
+	int idx = 0;
+	HKEY hVal;
+	while (RegEnumKeyEx(hKey, idx++, enumbuf, &enum_size, 0, NULL, NULL, NULL) != ERROR_NO_MORE_ITEMS)
+	{
+		enum_size = 39;
+		if (RegOpenKeyEx(hKey, enumbuf, 0, KEY_QUERY_VALUE, &hVal) != ERROR_SUCCESS)
+			continue;
+		if (!get_res_nt(hVal, subkey, obuf))
+			RegCloseKey(hVal);
+		else
+		{
+			RegCloseKey(hVal);
+			return 1;
+		}
+	}
+	return 0;
+}
+#endif
+
+static int init_by_resolv_conf(ares_channel channel)
+{
+  FILE *fp;
+  char *line = NULL, *p;
+  int linesize, status, nservers = 0, nsort = 0;
+  struct server_state *servers = NULL;
+  struct apattern *sortlist = NULL;
+
+#ifdef WIN32
+
+    /*
+  NameServer Registry:
+
+   On Windows 9X, the DNS server can be found in:
+HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\VxD\MSTCP\NameServer
+
+	On Windows NT/2000/XP/2003:
+HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\NameServer
+	or
+HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\DhcpNameServer
+	or
+HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\{AdapterID}\
+NameServer
+	or
+HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\{AdapterID}\
+DhcpNameServer
+   */
+
+  HKEY mykey;
+  HKEY subkey;
+  DWORD data_type;
+  DWORD bytes;
+  DWORD result;
+  DWORD index;
+  char name[MAX_PATH];
+  DWORD keysize = MAX_PATH;
+
+  status = ARES_EFILE;
+
+  if (IsNT) 
+  {
+    if (RegOpenKeyEx(
+            HKEY_LOCAL_MACHINE, WIN_NS_NT_KEY, 0,
+            KEY_READ, &mykey
+        ) == ERROR_SUCCESS)
+    {
+		RegOpenKeyEx(mykey, "Interfaces", 0, KEY_QUERY_VALUE|KEY_ENUMERATE_SUB_KEYS, &subkey);
+		if (get_res_nt(mykey, NAMESERVER, &line))
+		{
+			status = config_nameserver(&servers, &nservers, line);
+			free(line);
+		}
+		else if (get_res_nt(mykey, DHCPNAMESERVER, &line))
+		{
+			status = config_nameserver(&servers, &nservers, line);
+			free(line);
+		}
+		/* Try the interfaces */
+		else if (get_res_interfaces_nt(subkey, NAMESERVER, &line))
+		{
+			status = config_nameserver(&servers, &nservers, line);
+			free(line);
+		}
+		else if (get_res_interfaces_nt(subkey, DHCPNAMESERVER, &line))
+		{
+			status = config_nameserver(&servers, &nservers, line);
+			free(line);
+		}
+		RegCloseKey(subkey);
+	    RegCloseKey(mykey);
+	}
+  } else {
+      if (RegOpenKeyEx(
+            HKEY_LOCAL_MACHINE, WIN_NS_9X, 0,
+            KEY_READ, &mykey
+          ) == ERROR_SUCCESS)
+      {
+        if ((result = RegQueryValueEx(
+                        mykey, NAMESERVER, NULL, &data_type,
+                        NULL, &bytes
+                      ) 
+            ) == ERROR_SUCCESS ||
+            result == ERROR_MORE_DATA)
+        {
+            if (bytes) {
+                line = (char *)malloc(bytes+1);
+                if (RegQueryValueEx(
+                    mykey, NAMESERVER, NULL, &data_type,
+                    (unsigned char *)line, &bytes
+                    ) == ERROR_SUCCESS) {
+                    status = config_nameserver(&servers, &nservers, line);
+                }
+                free(line);
+            }
+        }
+      } 
+      RegCloseKey(mykey);
+  }
+  
+  if (status != ARES_EFILE) {
+      /*
+      if (!channel->lookups) {
+          status = config_lookup(channel, "file bind");
+      }
+      */
+      status = ARES_EOF;
+  }
+
+#elif defined(riscos)
+
+  /* Under RISC OS, name servers are listed in the
+     system variable Inet$Resolvers, space separated. */
+
+  line = getenv("Inet$Resolvers");
+  status = ARES_EFILE;
+  if (line) {
+    char *resolvers = strdup(line), *pos, *space;
+
+    if (!resolvers)
+      return ARES_ENOMEM;
+
+    pos = resolvers;
+    do {
+      space = strchr(pos, ' ');
+      if (space)
+        *space = 0;
+      status = config_nameserver(&servers, &nservers, pos);
+      if (status != ARES_SUCCESS)
+        break;
+      pos = space + 1;
+    } while (space);
+
+    if (status == ARES_SUCCESS)
+      status = ARES_EOF;
+
+    free(resolvers);
+  }
+
+#else
+
+  fp = fopen(PATH_RESOLV_CONF, "r");
+  if (!fp)
+    return (errno == ENOENT) ? ARES_SUCCESS : ARES_EFILE;
+  while ((status = ares__read_line(fp, &line, &linesize)) == ARES_SUCCESS)
+    {
+      if ((p = try_config(line, "domain")) && channel->ndomains == -1)
+	status = config_domain(channel, p);
+      else if ((p = try_config(line, "lookup")) && !channel->lookups)
+	status = config_lookup(channel, p);
+      else if ((p = try_config(line, "search")) && channel->ndomains == -1)
+	status = set_search(channel, p);
+      else if ((p = try_config(line, "nameserver")) && channel->nservers == -1)
+	status = config_nameserver(&servers, &nservers, p);
+      else if ((p = try_config(line, "sortlist")) && channel->nsort == -1)
+	status = config_sortlist(&sortlist, &nsort, p);
+      else if ((p = try_config(line, "options")))
+	status = set_options(channel, p);
+      else
+	status = ARES_SUCCESS;
+      if (status != ARES_SUCCESS)
+	break;
+    }
+  free(line);
+  fclose(fp);
+
+#endif
+
+  /* Handle errors. */
+  if (status != ARES_EOF)
+    {
+      if (servers != NULL) free(servers);
+      if (sortlist != NULL) free(sortlist);
+      return status;
+    }
+
+  /* If we got any name server entries, fill them in. */
+  if (servers)
+    {
+      channel->servers = servers;
+      channel->nservers = nservers;
+    }
+
+  /* If we got any sortlist entries, fill them in. */
+  if (sortlist)
+    {
+      channel->sortlist = sortlist;
+      channel->nsort = nsort;
+    }
+
+  return ARES_SUCCESS;
+}
+
+static int init_by_defaults(ares_channel channel)
+{
+  char hostname[MAXHOSTNAMELEN + 1];
+
+  if (channel->flags == -1)
+    channel->flags = 0;
+  if (channel->timeout == -1)
+    channel->timeout = DEFAULT_TIMEOUT;
+  if (channel->tries == -1)
+    channel->tries = DEFAULT_TRIES;
+  if (channel->ndots == -1)
+    channel->ndots = 1;
+  if (channel->udp_port == -1)
+    channel->udp_port = htons(NAMESERVER_PORT);
+  if (channel->tcp_port == -1)
+    channel->tcp_port = htons(NAMESERVER_PORT);
+
+  if (channel->nservers == -1)
+    {
+      /* If nobody specified servers, try a local named. */
+      channel->servers = malloc(sizeof(struct server_state));
+      if (!channel->servers)
+	return ARES_ENOMEM;
+      channel->servers[0].addr.s_addr = htonl(INADDR_LOOPBACK);
+      channel->nservers = 1;
+    }
+
+  if (channel->ndomains == -1)
+    {
+      /* Derive a default domain search list from the kernel hostname,
+       * or set it to empty if the hostname isn't helpful.
+       */
+      if (gethostname(hostname, sizeof(hostname)) == -1
+	  || !strchr(hostname, '.'))
+	{
+	  channel->domains = malloc(0);
+	  channel->ndomains = 0;
+	}
+      else
+	{
+	  channel->domains = malloc(sizeof(char *));
+	  if (!channel->domains)
+	    return ARES_ENOMEM;
+	  channel->ndomains = 0;
+	  channel->domains[0] = strdup(strchr(hostname, '.') + 1);
+	  if (!channel->domains[0])
+	    return ARES_ENOMEM;
+	  channel->ndomains = 1;
+	}
+    }
+
+  if (channel->nsort == -1)
+    {
+      channel->sortlist = NULL;
+      channel->nsort = 0;
+    }
+
+  if (!channel->lookups)
+    {
+      channel->lookups = strdup("bf");
+      if (!channel->lookups)
+	return ARES_ENOMEM;
+    }
+
+  return ARES_SUCCESS;
+}
+
+static int config_domain(ares_channel channel, char *str)
+{
+  char *q;
+
+  /* Set a single search domain. */
+  q = str;
+  while (*q && !isspace((unsigned char)*q))
+    q++;
+  *q = 0;
+  return set_search(channel, str);
+}
+
+static int config_lookup(ares_channel channel, const char *str)
+{
+  char lookups[3], *l;
+  const char *p;
+
+  /* Set the lookup order.  Only the first letter of each work
+   * is relevant, and it has to be "b" for DNS or "f" for the
+   * host file.  Ignore everything else.
+   */
+  l = lookups;
+  p = str;
+  while (*p)
+    {
+      if ((*p == 'b' || *p == 'f') && l < lookups + 2)
+	*l++ = *p;
+      while (*p && !isspace((unsigned char)*p))
+	p++;
+      while (isspace((unsigned char)*p))
+	p++;
+    }
+  *l = 0;
+  channel->lookups = strdup(lookups);
+  return (channel->lookups) ? ARES_SUCCESS : ARES_ENOMEM;
+}
+
+static int config_nameserver(struct server_state **servers, int *nservers,
+			     const char *str)
+{
+  struct in_addr addr;
+  struct server_state *newserv;
+
+  /* Add a nameserver entry, if this is a valid address. */
+  addr.s_addr = inet_addr(str);
+  if (addr.s_addr == INADDR_NONE)
+    return ARES_SUCCESS;
+  newserv = realloc(*servers, (*nservers + 1) * sizeof(struct server_state));
+  if (!newserv)
+    return ARES_ENOMEM;
+  newserv[*nservers].addr = addr;
+  *servers = newserv;
+  (*nservers)++;
+  return ARES_SUCCESS;
+}
+
+static int config_sortlist(struct apattern **sortlist, int *nsort,
+			   const char *str)
+{
+  struct apattern pat, *newsort;
+  const char *q;
+
+  /* Add sortlist entries. */
+  while (*str && *str != ';')
+    {
+      q = str;
+      while (*q && *q != '/' && *q != ';' && !isspace((unsigned char)*q))
+	q++;
+      if (ip_addr(str, q - str, &pat.addr) == 0)
+	{
+	  /* We have a pattern address; now determine the mask. */
+	  if (*q == '/')
+	    {
+	      str = q + 1;
+	      while (*q && *q != ';' && !isspace((unsigned char)*q))
+		q++;
+	      if (ip_addr(str, q - str, &pat.mask) != 0)
+		natural_mask(&pat);
+	    }
+	  else
+	    natural_mask(&pat);
+
+	  /* Add this pattern to our list. */
+	  newsort = realloc(*sortlist, (*nsort + 1) * sizeof(struct apattern));
+	  if (!newsort)
+	    return ARES_ENOMEM;
+	  newsort[*nsort] = pat;
+	  *sortlist = newsort;
+	  (*nsort)++;
+	}
+      else
+	{
+	  while (*q && *q != ';' && !isspace((unsigned char)*q))
+	    q++;
+	}
+      str = q;
+      while (isspace((unsigned char)*str))
+	str++;
+    }
+
+  return ARES_SUCCESS;
+}
+
+static int set_search(ares_channel channel, const char *str)
+{
+  int n;
+  const char *p, *q;
+
+  /* Count the domains given. */
+  n = 0;
+  p = str;
+  while (*p)
+    {
+      while (*p && !isspace((unsigned char)*p))
+	p++;
+      while (isspace((unsigned char)*p))
+	p++;
+      n++;
+    }
+
+  channel->domains = malloc(n * sizeof(char *));
+  if (!channel->domains && n)
+    return ARES_ENOMEM;
+
+  /* Now copy the domains. */
+  n = 0;
+  p = str;
+  while (*p)
+    {
+      channel->ndomains = n;
+      q = p;
+      while (*q && !isspace((unsigned char)*q))
+	q++;
+      channel->domains[n] = malloc(q - p + 1);
+      if (!channel->domains[n])
+	return ARES_ENOMEM;
+      memcpy(channel->domains[n], p, q - p);
+      channel->domains[n][q - p] = 0;
+      p = q;
+      while (isspace((unsigned char)*p))
+	p++;
+      n++;
+    }
+  channel->ndomains = n;
+
+  return ARES_SUCCESS;
+}
+
+static int set_options(ares_channel channel, const char *str)
+{
+  const char *p, *q, *val;
+
+  p = str;
+  while (*p)
+    {
+      q = p;
+      while (*q && !isspace((unsigned char)*q))
+	q++;
+      val = try_option(p, q, "ndots:");
+      if (val && channel->ndots == -1)
+	channel->ndots = atoi(val);
+      val = try_option(p, q, "retrans:");
+      if (val && channel->timeout == -1)
+	channel->timeout = atoi(val);
+      val = try_option(p, q, "retry:");
+      if (val && channel->tries == -1)
+	channel->tries = atoi(val);
+      p = q;
+      while (isspace((unsigned char)*p))
+	p++;
+    }
+
+  return ARES_SUCCESS;
+}
+
+static char *try_config(char *s, char *opt)
+{
+  int len;
+
+  len = strlen(opt);
+  if (strncmp(s, opt, len) != 0 || !isspace((unsigned char)s[len]))
+    return NULL;
+  s += len;
+  while (isspace((unsigned char)*s))
+    s++;
+  return s;
+}
+
+static const char *try_option(const char *p, const char *q, const char *opt)
+{
+  int len;
+
+  len = strlen(opt);
+  return (q - p > len && strncmp(p, opt, len) == 0) ? p + len : NULL;
+}
+
+static int ip_addr(const char *s, int len, struct in_addr *addr)
+{
+  char ipbuf[16];
+
+  /* Four octets and three periods yields at most 15 characters. */
+  if (len > 15)
+    return -1;
+  memcpy(ipbuf, s, len);
+  ipbuf[len] = 0;
+
+  addr->s_addr = inet_addr(ipbuf);
+  if (addr->s_addr == INADDR_NONE && strcmp(ipbuf, "255.255.255.255") != 0)
+    return -1;
+  return 0;
+}
+
+static void natural_mask(struct apattern *pat)
+{
+  struct in_addr addr;
+
+  /* Store a host-byte-order copy of pat in a struct in_addr.  Icky,
+   * but portable.
+   */
+  addr.s_addr = ntohl(pat->addr.s_addr);
+
+  /* This is out of date in the CIDR world, but some people might
+   * still rely on it.
+   */
+  if (IN_CLASSA(addr.s_addr))
+    pat->mask.s_addr = htonl(IN_CLASSA_NET);
+  else if (IN_CLASSB(addr.s_addr))
+    pat->mask.s_addr = htonl(IN_CLASSB_NET);
+  else
+    pat->mask.s_addr = htonl(IN_CLASSC_NET);
+}