1 files changed, 132 insertions, 334 deletions

diff --git a/src/lib/ares_gethostbyname.c b/src/lib/ares_gethostbyname.c
index 4e41898..8c71cc6 100644
--- a/src/lib/ares_gethostbyname.c
+++ b/src/lib/ares_gethostbyname.c
@@ -1,4 +1,3 @@
-
 /* Copyright 1998, 2011, 2013 by the Massachusetts Institute of Technology.
  *
  * Permission to use, copy, modify, and distribute this
@@ -25,14 +24,8 @@
 #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
+
+#include "ares_nameser.h"
 
 #ifdef HAVE_STRINGS_H
 #include <strings.h>
@@ -45,30 +38,6 @@
 #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,
@@ -78,252 +47,182 @@ static int get_address_index(const struct in_addr *addr,
 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 {
+  ares_host_callback callback;
+  void *arg;
+  ares_channel channel;
+};
+
+static void ares_gethostbyname_callback(void *arg, int status, int timeouts,
+                                        struct ares_addrinfo *result)
 {
-  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;
-  }
+  struct hostent *hostent = NULL;
+  struct host_query *ghbn_arg = arg;
 
-  /* Per RFC 7686, reject queries for ".onion" domain names with NXDOMAIN. */
-  if (ares__is_onion_domain(name))
+  if (status == ARES_SUCCESS)
     {
-      callback(arg, ARES_ENOTFOUND, 0, NULL);
-      return;
+      status = ares__addrinfo2hostent(result, AF_UNSPEC, &hostent);
+    }
+
+  /* addrinfo2hostent will only return ENODATA if there are no addresses _and_
+   * no cname/aliases.  However, gethostbyname will return ENODATA even if there
+   * is cname/alias data */
+  if (status == ARES_SUCCESS && hostent &&
+      (!hostent->h_addr_list || !hostent->h_addr_list[0]))
+    {
+      status = ARES_ENODATA;
     }
 
-  if (fake_hostent(name, family, callback, arg))
+  if (status == ARES_SUCCESS && ghbn_arg->channel->nsort && hostent)
+    {
+      if (hostent->h_addrtype == AF_INET6)
+        sort6_addresses(hostent, ghbn_arg->channel->sortlist,
+                        ghbn_arg->channel->nsort);
+      if (hostent->h_addrtype == AF_INET)
+        sort_addresses(hostent, ghbn_arg->channel->sortlist,
+                       ghbn_arg->channel->nsort);
+    }
+
+  ghbn_arg->callback(ghbn_arg->arg, status, timeouts, hostent);
+
+  ares_freeaddrinfo(result);
+  ares_free(ghbn_arg);
+  ares_free_hostent(hostent);
+}
+
+void ares_gethostbyname(ares_channel channel, const char *name, int family,
+                        ares_host_callback callback, void *arg)
+{
+  const struct ares_addrinfo_hints hints = { ARES_AI_CANONNAME, family, 0, 0 };
+  struct host_query *ghbn_arg;
+
+  if (!callback)
     return;
 
-  /* Allocate and fill in the host query structure. */
-  hquery = ares_malloc(sizeof(struct host_query));
-  if (!hquery)
+  ghbn_arg = ares_malloc(sizeof(*ghbn_arg));
+  if (!ghbn_arg)
     {
       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 */);
+  ghbn_arg->callback=callback;
+  ghbn_arg->arg=arg;
+  ghbn_arg->channel=channel;
+
+  ares_getaddrinfo(channel, name, NULL, &hints, ares_gethostbyname_callback,
+                   ghbn_arg);
 }
 
-static void next_lookup(struct host_query *hquery, int status_code)
+
+static void sort_addresses(struct hostent *host,
+                           const struct apattern *sortlist, int nsort)
 {
-  const char *p;
-  struct hostent *host;
-  int status = status_code;
+  struct in_addr a1, a2;
+  int i1, i2, ind1, ind2;
 
-  for (p = hquery->remaining_lookups; *p; p++)
+  /* 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++)
     {
-      switch (*p)
+      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--)
         {
-        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;
+          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));
     }
-  end_hquery(hquery, status, NULL);
 }
 
-static void host_callback(void *arg, int status, int timeouts,
-                          unsigned char *abuf, int alen)
+/* 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)
 {
-  struct host_query *hquery = (struct host_query *) arg;
-  ares_channel channel = hquery->channel;
-  struct hostent *host = NULL;
+  int i;
 
-  hquery->timeouts += timeouts;
-  if (status == ARES_SUCCESS)
+  for (i = 0; i < nsort; i++)
     {
-      if (hquery->sent_family == AF_INET)
+      if (sortlist[i].family != AF_INET)
+        continue;
+      if (sortlist[i].type == PATTERN_MASK)
         {
-          status = ares_parse_a_reply(abuf, alen, &host, NULL, NULL);
-          if (host && channel->nsort)
-            sort_addresses(host, channel->sortlist, channel->nsort);
+          if ((addr->s_addr & sortlist[i].mask.addr4.s_addr)
+              == sortlist[i].addrV4.s_addr)
+            break;
         }
-      else if (hquery->sent_family == AF_INET6)
+      else
         {
-          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);
+          if (!ares__bitncmp(&addr->s_addr, &sortlist[i].addrV4.s_addr,
+                             sortlist[i].mask.bits))
+            break;
         }
-      if (status == ARES_SUCCESS && host && host->h_addr_list[0] == NULL)
-      {
-        /* The query returned something but had no A/AAAA record
-           (even after potentially retrying AAAA with A)
-           so we should treat this as an error */
-        status = ARES_ENODATA;
-      }
-      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);
+  return i;
 }
 
-static void end_hquery(struct host_query *hquery, int status,
-                       struct hostent *host)
+static void sort6_addresses(struct hostent *host,
+                            const struct apattern *sortlist, int nsort)
 {
-  hquery->callback(hquery->arg, status, hquery->timeouts, host);
-  if (host)
-    ares_free_hostent(host);
-  ares_free(hquery->name);
-  ares_free(hquery);
-}
+  struct ares_in6_addr a1, a2;
+  int i1, i2, ind1, ind2;
 
-/* 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_UNSPEC)
+  /* 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++)
     {
-      /* 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++)
+      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--)
         {
-          if (!ISDIGIT(*p) && *p != '.') {
-            valid = 0;
+          memcpy(&a2, host->h_addr_list[i2], sizeof(struct ares_in6_addr));
+          ind2 = get6_address_index(&a2, sortlist, nsort);
+          if (ind2 <= ind1)
             break;
-          } else if (*p == '.') {
-            numdots++;
-          }
+          memcpy(host->h_addr_list[i2 + 1], &a2, sizeof(struct ares_in6_addr));
         }
-
-      /* if we don't have 3 dots, it is illegal
-       * (although inet_pton doesn't think so).
-       */
-      if (numdots != 3 || !valid) {
-        result = 0;
-      } else {
-        result = (ares_inet_pton(AF_INET, name, &in) < 1 ? 0 : 1);
-      }
-
-      /*
-       * Set address family in case of failure,
-       * as we will try to convert it later afterwards
-       */
-      family = result ? AF_INET : AF_INET6;
+      memcpy(host->h_addr_list[i2 + 1], &a1, sizeof(struct ares_in6_addr));
     }
-  if (family == AF_INET6)
-    result = (ares_inet_pton(AF_INET6, name, &in6) < 1 ? 0 : 1);
+}
 
-  if (!result)
-    return 0;
+/* 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;
 
-  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)
+  for (i = 0; i < nsort; i++)
     {
-      callback(arg, ARES_ENOMEM, 0, NULL);
-      return 1;
+      if (sortlist[i].family != AF_INET6)
+        continue;
+      if (!ares__bitncmp(addr, &sortlist[i].addrV6, sortlist[i].mask.bits))
+        break;
     }
+  return i;
+}
 
-  /* 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 */
+static int file_lookup(const char *name, int family, struct hostent **host);
+
+/* I really have no idea why this is exposed as a public function, but since
+ * it is, we can't kill this legacy function. */
 int ares_gethostbyname_file(ares_channel channel, const char *name,
                             int family, struct hostent **host)
 {
@@ -437,104 +336,3 @@ static int file_lookup(const char *name, int family, struct hostent **host)
   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;
-}