Adding upstream version 16.2.11+ds.upstream/16.2.11+dsupstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 518 insertions, 0 deletions

diff --git a/src/c-ares/ares_gethostbyname.c b/src/c-ares/ares_gethostbyname.c
new file mode 100644
index 000000000..caab6ae49
--- /dev/null
+++ b/src/c-ares/ares_gethostbyname.c
@@ -0,0 +1,518 @@
+
+/* Copyright 1998, 2011, 2013 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.
+ */
+
+#include "ares_setup.h"
+
+#ifdef HAVE_NETINET_IN_H
+#  include <netinet/in.h>
+#endif
+#ifdef HAVE_NETDB_H
+#  include <netdb.h>
+#endif
+#ifdef HAVE_ARPA_INET_H
+#  include <arpa/inet.h>
+#endif
+#ifdef HAVE_ARPA_NAMESER_H
+#  include <arpa/nameser.h>
+#else
+#  include "nameser.h"
+#endif
+#ifdef HAVE_ARPA_NAMESER_COMPAT_H
+#  include <arpa/nameser_compat.h>
+#endif
+
+#ifdef HAVE_STRINGS_H
+#include <strings.h>
+#endif
+
+#include "ares.h"
+#include "ares_inet_net_pton.h"
+#include "bitncmp.h"
+#include "ares_platform.h"
+#include "ares_nowarn.h"
+#include "ares_private.h"
+
+#ifdef WATT32
+#undef WIN32
+#endif
+
+struct host_query {
+  /* Arguments passed to ares_gethostbyname() */
+  ares_channel channel;
+  char *name;
+  ares_host_callback callback;
+  void *arg;
+  int sent_family; /* this family is what was is being used */
+  int want_family; /* this family is what is asked for in the API */
+  const char *remaining_lookups;
+  int timeouts;
+};
+
+static void next_lookup(struct host_query *hquery, int status_code);
+static void host_callback(void *arg, int status, int timeouts,
+                          unsigned char *abuf, int alen);
+static void end_hquery(struct host_query *hquery, int status,
+                       struct hostent *host);
+static int fake_hostent(const char *name, int family,
+                        ares_host_callback callback, void *arg);
+static int file_lookup(const char *name, int family, struct hostent **host);
+static void sort_addresses(struct hostent *host,
+                           const struct apattern *sortlist, int nsort);
+static void sort6_addresses(struct hostent *host,
+                            const struct apattern *sortlist, int nsort);
+static int get_address_index(const struct in_addr *addr,
+                             const struct apattern *sortlist, int nsort);
+static int get6_address_index(const struct ares_in6_addr *addr,
+                              const struct apattern *sortlist, int nsort);
+
+void ares_gethostbyname(ares_channel channel, const char *name, int family,
+                        ares_host_callback callback, void *arg)
+{
+  struct host_query *hquery;
+
+  /* Right now we only know how to look up Internet addresses - and unspec
+     means try both basically. */
+  switch (family) {
+  case AF_INET:
+  case AF_INET6:
+  case AF_UNSPEC:
+    break;
+  default:
+    callback(arg, ARES_ENOTIMP, 0, NULL);
+    return;
+  }
+
+  if (fake_hostent(name, family, callback, arg))
+    return;
+
+  /* Allocate and fill in the host query structure. */
+  hquery = ares_malloc(sizeof(struct host_query));
+  if (!hquery)
+    {
+      callback(arg, ARES_ENOMEM, 0, NULL);
+      return;
+    }
+  hquery->channel = channel;
+  hquery->name = ares_strdup(name);
+  hquery->want_family = family;
+  hquery->sent_family = -1; /* nothing is sent yet */
+  if (!hquery->name) {
+    ares_free(hquery);
+    callback(arg, ARES_ENOMEM, 0, NULL);
+    return;
+  }
+  hquery->callback = callback;
+  hquery->arg = arg;
+  hquery->remaining_lookups = channel->lookups;
+  hquery->timeouts = 0;
+
+  /* Start performing lookups according to channel->lookups. */
+  next_lookup(hquery, ARES_ECONNREFUSED /* initial error code */);
+}
+
+static void next_lookup(struct host_query *hquery, int status_code)
+{
+  const char *p;
+  struct hostent *host;
+  int status = status_code;
+
+  for (p = hquery->remaining_lookups; *p; p++)
+    {
+      switch (*p)
+        {
+        case 'b':
+          /* DNS lookup */
+          hquery->remaining_lookups = p + 1;
+          if ((hquery->want_family == AF_INET6) ||
+              (hquery->want_family == AF_UNSPEC)) {
+            /* if inet6 or unspec, start out with AAAA */
+            hquery->sent_family = AF_INET6;
+            ares_search(hquery->channel, hquery->name, C_IN, T_AAAA,
+                        host_callback, hquery);
+          }
+          else {
+            hquery->sent_family = AF_INET;
+            ares_search(hquery->channel, hquery->name, C_IN, T_A,
+                        host_callback, hquery);
+          }
+          return;
+
+        case 'f':
+          /* Host file lookup */
+          status = file_lookup(hquery->name, hquery->want_family, &host);
+
+          /* this status check below previously checked for !ARES_ENOTFOUND,
+             but we should not assume that this single error code is the one
+             that can occur, as that is in fact no longer the case */
+          if (status == ARES_SUCCESS)
+            {
+              end_hquery(hquery, status, host);
+              return;
+            }
+          status = status_code;   /* Use original status code */
+          break;
+        }
+    }
+  end_hquery(hquery, status, NULL);
+}
+
+static void host_callback(void *arg, int status, int timeouts,
+                          unsigned char *abuf, int alen)
+{
+  struct host_query *hquery = (struct host_query *) arg;
+  ares_channel channel = hquery->channel;
+  struct hostent *host = NULL;
+
+  hquery->timeouts += timeouts;
+  if (status == ARES_SUCCESS)
+    {
+      if (hquery->sent_family == AF_INET)
+        {
+          status = ares_parse_a_reply(abuf, alen, &host, NULL, NULL);
+          if (host && channel->nsort)
+            sort_addresses(host, channel->sortlist, channel->nsort);
+        }
+      else if (hquery->sent_family == AF_INET6)
+        {
+          status = ares_parse_aaaa_reply(abuf, alen, &host, NULL, NULL);
+          if ((status == ARES_ENODATA || status == ARES_EBADRESP ||
+               (status == ARES_SUCCESS && host && host->h_addr_list[0] == NULL)) &&
+                hquery->want_family == AF_UNSPEC) {
+            /* The query returned something but either there were no AAAA
+               records (e.g. just CNAME) or the response was malformed.  Try
+               looking up A instead. */
+            if (host)
+              ares_free_hostent(host);
+            hquery->sent_family = AF_INET;
+            ares_search(hquery->channel, hquery->name, C_IN, T_A,
+                        host_callback, hquery);
+            return;
+          }
+          if (host && channel->nsort)
+            sort6_addresses(host, channel->sortlist, channel->nsort);
+        }
+      end_hquery(hquery, status, host);
+    }
+  else if ((status == ARES_ENODATA || status == ARES_EBADRESP ||
+            status == ARES_ETIMEOUT) && (hquery->sent_family == AF_INET6 &&
+            hquery->want_family == AF_UNSPEC))
+    {
+      /* The AAAA query yielded no useful result.  Now look up an A instead. */
+      hquery->sent_family = AF_INET;
+      ares_search(hquery->channel, hquery->name, C_IN, T_A, host_callback,
+                  hquery);
+    }
+  else if (status == ARES_EDESTRUCTION)
+    end_hquery(hquery, status, NULL);
+  else
+    next_lookup(hquery, status);
+}
+
+static void end_hquery(struct host_query *hquery, int status,
+                       struct hostent *host)
+{
+  hquery->callback(hquery->arg, status, hquery->timeouts, host);
+  if (host)
+    ares_free_hostent(host);
+  ares_free(hquery->name);
+  ares_free(hquery);
+}
+
+/* If the name looks like an IP address, fake up a host entry, end the
+ * query immediately, and return true.  Otherwise return false.
+ */
+static int fake_hostent(const char *name, int family,
+                        ares_host_callback callback, void *arg)
+{
+  struct hostent hostent;
+  char *aliases[1] = { NULL };
+  char *addrs[2];
+  int result = 0;
+  struct in_addr in;
+  struct ares_in6_addr in6;
+
+  if (family == AF_INET || family == AF_INET6)
+    {
+      /* It only looks like an IP address if it's all numbers and dots. */
+      int numdots = 0, valid = 1;
+      const char *p;
+      for (p = name; *p; p++)
+        {
+          if (!ISDIGIT(*p) && *p != '.') {
+            valid = 0;
+            break;
+          } else if (*p == '.') {
+            numdots++;
+          }
+        }
+
+      /* if we don't have 3 dots, it is illegal
+       * (although inet_addr doesn't think so).
+       */
+      if (numdots != 3 || !valid)
+        result = 0;
+      else
+        result = ((in.s_addr = inet_addr(name)) == INADDR_NONE ? 0 : 1);
+
+      if (result)
+        family = AF_INET;
+    }
+  if (family == AF_INET6)
+    result = (ares_inet_pton(AF_INET6, name, &in6) < 1 ? 0 : 1);
+
+  if (!result)
+    return 0;
+
+  if (family == AF_INET)
+    {
+      hostent.h_length = (int)sizeof(struct in_addr);
+      addrs[0] = (char *)&in;
+    }
+  else if (family == AF_INET6)
+    {
+      hostent.h_length = (int)sizeof(struct ares_in6_addr);
+      addrs[0] = (char *)&in6;
+    }
+  /* Duplicate the name, to avoid a constness violation. */
+  hostent.h_name = ares_strdup(name);
+  if (!hostent.h_name)
+    {
+      callback(arg, ARES_ENOMEM, 0, NULL);
+      return 1;
+    }
+
+  /* Fill in the rest of the host structure and terminate the query. */
+  addrs[1] = NULL;
+  hostent.h_aliases = aliases;
+  hostent.h_addrtype = aresx_sitoss(family);
+  hostent.h_addr_list = addrs;
+  callback(arg, ARES_SUCCESS, 0, &hostent);
+
+  ares_free((char *)(hostent.h_name));
+  return 1;
+}
+
+/* This is an API method */
+int ares_gethostbyname_file(ares_channel channel, const char *name,
+                            int family, struct hostent **host)
+{
+  int result;
+
+  /* We only take the channel to ensure that ares_init() been called. */
+  if(channel == NULL)
+    {
+      /* Anything will do, really.  This seems fine, and is consistent with
+         other error cases. */
+      *host = NULL;
+      return ARES_ENOTFOUND;
+    }
+
+  /* Just chain to the internal implementation we use here; it's exactly
+   * what we want.
+   */
+  result = file_lookup(name, family, host);
+  if(result != ARES_SUCCESS)
+    {
+      /* We guarantee a NULL hostent on failure. */
+      *host = NULL;
+    }
+  return result;
+}
+
+static int file_lookup(const char *name, int family, struct hostent **host)
+{
+  FILE *fp;
+  char **alias;
+  int status;
+  int error;
+
+#ifdef WIN32
+  char PATH_HOSTS[MAX_PATH];
+  win_platform platform;
+
+  PATH_HOSTS[0] = '\0';
+
+  platform = ares__getplatform();
+
+  if (platform == WIN_NT) {
+    char tmp[MAX_PATH];
+    HKEY hkeyHosts;
+
+    if (RegOpenKeyEx(HKEY_LOCAL_MACHINE, WIN_NS_NT_KEY, 0, KEY_READ,
+                     &hkeyHosts) == ERROR_SUCCESS)
+    {
+      DWORD dwLength = MAX_PATH;
+      RegQueryValueEx(hkeyHosts, DATABASEPATH, NULL, NULL, (LPBYTE)tmp,
+                      &dwLength);
+      ExpandEnvironmentStrings(tmp, PATH_HOSTS, MAX_PATH);
+      RegCloseKey(hkeyHosts);
+    }
+  }
+  else if (platform == WIN_9X)
+    GetWindowsDirectory(PATH_HOSTS, MAX_PATH);
+  else
+    return ARES_ENOTFOUND;
+
+  strcat(PATH_HOSTS, WIN_PATH_HOSTS);
+
+#elif defined(WATT32)
+  extern const char *_w32_GetHostsFile (void);
+  const char *PATH_HOSTS = _w32_GetHostsFile();
+
+  if (!PATH_HOSTS)
+    return ARES_ENOTFOUND;
+#endif
+
+  fp = fopen(PATH_HOSTS, "r");
+  if (!fp)
+    {
+      error = ERRNO;
+      switch(error)
+        {
+        case ENOENT:
+        case ESRCH:
+          return ARES_ENOTFOUND;
+        default:
+          DEBUGF(fprintf(stderr, "fopen() failed with error: %d %s\n",
+                         error, strerror(error)));
+          DEBUGF(fprintf(stderr, "Error opening file: %s\n",
+                         PATH_HOSTS));
+          *host = NULL;
+          return ARES_EFILE;
+        }
+    }
+  while ((status = ares__get_hostent(fp, family, host)) == ARES_SUCCESS)
+    {
+      if (strcasecmp((*host)->h_name, name) == 0)
+        break;
+      for (alias = (*host)->h_aliases; *alias; alias++)
+        {
+          if (strcasecmp(*alias, name) == 0)
+            break;
+        }
+      if (*alias)
+        break;
+      ares_free_hostent(*host);
+    }
+  fclose(fp);
+  if (status == ARES_EOF)
+    status = ARES_ENOTFOUND;
+  if (status != ARES_SUCCESS)
+    *host = NULL;
+  return status;
+}
+
+static void sort_addresses(struct hostent *host,
+                           const struct apattern *sortlist, int nsort)
+{
+  struct in_addr a1, a2;
+  int i1, i2, ind1, ind2;
+
+  /* This is a simple insertion sort, not optimized at all.  i1 walks
+   * through the address list, with the loop invariant that everything
+   * to the left of i1 is sorted.  In the loop body, the value at i1 is moved
+   * back through the list (via i2) until it is in sorted order.
+   */
+  for (i1 = 0; host->h_addr_list[i1]; i1++)
+    {
+      memcpy(&a1, host->h_addr_list[i1], sizeof(struct in_addr));
+      ind1 = get_address_index(&a1, sortlist, nsort);
+      for (i2 = i1 - 1; i2 >= 0; i2--)
+        {
+          memcpy(&a2, host->h_addr_list[i2], sizeof(struct in_addr));
+          ind2 = get_address_index(&a2, sortlist, nsort);
+          if (ind2 <= ind1)
+            break;
+          memcpy(host->h_addr_list[i2 + 1], &a2, sizeof(struct in_addr));
+        }
+      memcpy(host->h_addr_list[i2 + 1], &a1, sizeof(struct in_addr));
+    }
+}
+
+/* Find the first entry in sortlist which matches addr.  Return nsort
+ * if none of them match.
+ */
+static int get_address_index(const struct in_addr *addr,
+                             const struct apattern *sortlist,
+                             int nsort)
+{
+  int i;
+
+  for (i = 0; i < nsort; i++)
+    {
+      if (sortlist[i].family != AF_INET)
+        continue;
+      if (sortlist[i].type == PATTERN_MASK)
+        {
+          if ((addr->s_addr & sortlist[i].mask.addr4.s_addr)
+              == sortlist[i].addrV4.s_addr)
+            break;
+        }
+      else
+        {
+          if (!ares__bitncmp(&addr->s_addr, &sortlist[i].addrV4.s_addr,
+                             sortlist[i].mask.bits))
+            break;
+        }
+    }
+  return i;
+}
+
+static void sort6_addresses(struct hostent *host,
+                            const struct apattern *sortlist, int nsort)
+{
+  struct ares_in6_addr a1, a2;
+  int i1, i2, ind1, ind2;
+
+  /* This is a simple insertion sort, not optimized at all.  i1 walks
+   * through the address list, with the loop invariant that everything
+   * to the left of i1 is sorted.  In the loop body, the value at i1 is moved
+   * back through the list (via i2) until it is in sorted order.
+   */
+  for (i1 = 0; host->h_addr_list[i1]; i1++)
+    {
+      memcpy(&a1, host->h_addr_list[i1], sizeof(struct ares_in6_addr));
+      ind1 = get6_address_index(&a1, sortlist, nsort);
+      for (i2 = i1 - 1; i2 >= 0; i2--)
+        {
+          memcpy(&a2, host->h_addr_list[i2], sizeof(struct ares_in6_addr));
+          ind2 = get6_address_index(&a2, sortlist, nsort);
+          if (ind2 <= ind1)
+            break;
+          memcpy(host->h_addr_list[i2 + 1], &a2, sizeof(struct ares_in6_addr));
+        }
+      memcpy(host->h_addr_list[i2 + 1], &a1, sizeof(struct ares_in6_addr));
+    }
+}
+
+/* Find the first entry in sortlist which matches addr.  Return nsort
+ * if none of them match.
+ */
+static int get6_address_index(const struct ares_in6_addr *addr,
+                              const struct apattern *sortlist,
+                              int nsort)
+{
+  int i;
+
+  for (i = 0; i < nsort; i++)
+    {
+      if (sortlist[i].family != AF_INET6)
+        continue;
+      if (!ares__bitncmp(addr, &sortlist[i].addrV6, sortlist[i].mask.bits))
+        break;
+    }
+  return i;
+}