1 files changed, 257 insertions, 0 deletions
diff --git a/3rdParty/CAres/src/ares_parse_a_reply.c b/3rdParty/CAres/src/ares_parse_a_reply.c
new file mode 100644
index 0000000..801c193
--- /dev/null
+++ b/3rdParty/CAres/src/ares_parse_a_reply.c
@@ -0,0 +1,257 @@
+/* $Id: ares_parse_a_reply.c,v 1.20 2009-11-23 01:24:17 yangtse Exp $ */
+
+/* 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.
+ */
+
+#include "ares_setup.h"
+
+#ifdef HAVE_SYS_SOCKET_H
+#  include <sys/socket.h>
+#endif
+#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 <stdlib.h>
+#include <string.h>
+#ifdef HAVE_LIMITS_H
+#  include <limits.h>
+#endif
+
+#include "ares.h"
+#include "ares_dns.h"
+#include "ares_private.h"
+
+int ares_parse_a_reply(const unsigned char *abuf, int alen,
+                       struct hostent **host,
+                       struct ares_addrttl *addrttls, int *naddrttls)
+{
+  unsigned int qdcount, ancount;
+  int status, i, rr_type, rr_class, rr_len, rr_ttl, naddrs;
+  int cname_ttl = INT_MAX;  /* the TTL imposed by the CNAME chain */
+  int naliases;
+  long len;
+  const unsigned char *aptr;
+  char *hostname, *rr_name, *rr_data, **aliases;
+  struct in_addr *addrs;
+  struct hostent *hostent;
+  const int max_addr_ttls = (addrttls && naddrttls) ? *naddrttls : 0;
+
+  /* Set *host to NULL for all failure cases. */
+  if (host)
+    *host = NULL;
+  /* Same with *naddrttls. */
+  if (naddrttls)
+    *naddrttls = 0;
+
+  /* Give up if abuf doesn't have room for a header. */
+  if (alen < HFIXEDSZ)
+    return ARES_EBADRESP;
+
+  /* Fetch the question and answer count from the header. */
+  qdcount = DNS_HEADER_QDCOUNT(abuf);
+  ancount = DNS_HEADER_ANCOUNT(abuf);
+  if (qdcount != 1)
+    return ARES_EBADRESP;
+
+  /* Expand the name from the question, and skip past the question. */
+  aptr = abuf + HFIXEDSZ;
+  status = ares__expand_name_for_response(aptr, abuf, alen, &hostname, &len);
+  if (status != ARES_SUCCESS)
+    return status;
+  if (aptr + len + QFIXEDSZ > abuf + alen)
+    {
+      free(hostname);
+      return ARES_EBADRESP;
+    }
+  aptr += len + QFIXEDSZ;
+
+  if (host)
+    {
+      /* Allocate addresses and aliases; ancount gives an upper bound for
+         both. */
+      addrs = malloc(ancount * sizeof(struct in_addr));
+      if (!addrs)
+        {
+          free(hostname);
+          return ARES_ENOMEM;
+        }
+      aliases = malloc((ancount + 1) * sizeof(char *));
+      if (!aliases)
+        {
+          free(hostname);
+          free(addrs);
+          return ARES_ENOMEM;
+        }
+    }
+  else
+    {
+      addrs = NULL;
+      aliases = NULL;
+    }
+
+  naddrs = 0;
+  naliases = 0;
+
+  /* Examine each answer resource record (RR) in turn. */
+  for (i = 0; i < (int)ancount; i++)
+    {
+      /* Decode the RR up to the data field. */
+      status = ares__expand_name_for_response(aptr, abuf, alen, &rr_name, &len);
+      if (status != ARES_SUCCESS)
+        break;
+      aptr += len;
+      if (aptr + RRFIXEDSZ > abuf + alen)
+        {
+          status = ARES_EBADRESP;
+          break;
+        }
+      rr_type = DNS_RR_TYPE(aptr);
+      rr_class = DNS_RR_CLASS(aptr);
+      rr_len = DNS_RR_LEN(aptr);
+      rr_ttl = DNS_RR_TTL(aptr);
+      aptr += RRFIXEDSZ;
+
+      if (rr_class == C_IN && rr_type == T_A
+          && rr_len == sizeof(struct in_addr)
+          && strcasecmp(rr_name, hostname) == 0)
+        {
+          if (addrs)
+            {
+              if (aptr + sizeof(struct in_addr) > abuf + alen)
+              {
+                status = ARES_EBADRESP;
+                break;
+              }
+              memcpy(&addrs[naddrs], aptr, sizeof(struct in_addr));
+            }
+          if (naddrs < max_addr_ttls)
+            {
+              struct ares_addrttl * const at = &addrttls[naddrs];
+              if (aptr + sizeof(struct in_addr) > abuf + alen)
+              {
+                status = ARES_EBADRESP;
+                break;
+              }
+              memcpy(&at->ipaddr, aptr,  sizeof(struct in_addr));
+              at->ttl = rr_ttl;
+            }
+          naddrs++;
+          status = ARES_SUCCESS;
+        }
+
+      if (rr_class == C_IN && rr_type == T_CNAME)
+        {
+          /* Record the RR name as an alias. */
+          if (aliases)
+            aliases[naliases] = rr_name;
+          else
+            free(rr_name);
+          naliases++;
+
+          /* Decode the RR data and replace the hostname with it. */
+          status = ares__expand_name_for_response(aptr, abuf, alen, &rr_data,
+                                                  &len);
+          if (status != ARES_SUCCESS)
+            break;
+          free(hostname);
+          hostname = rr_data;
+
+          /* Take the min of the TTLs we see in the CNAME chain. */
+          if (cname_ttl > rr_ttl)
+            cname_ttl = rr_ttl;
+        }
+      else
+        free(rr_name);
+
+      aptr += rr_len;
+      if (aptr > abuf + alen)
+        {
+          status = ARES_EBADRESP;
+          break;
+        }
+    }
+
+  if (status == ARES_SUCCESS && naddrs == 0)
+    status = ARES_ENODATA;
+  if (status == ARES_SUCCESS)
+    {
+      /* We got our answer. */
+      if (naddrttls)
+        {
+          const int n = naddrs < max_addr_ttls ? naddrs : max_addr_ttls;
+          for (i = 0; i < n; i++)
+            {
+              /* Ensure that each A TTL is no larger than the CNAME TTL. */
+              if (addrttls[i].ttl > cname_ttl)
+                addrttls[i].ttl = cname_ttl;
+            }
+          *naddrttls = n;
+        }
+      if (aliases)
+        aliases[naliases] = NULL;
+      if (host)
+        {
+          /* Allocate memory to build the host entry. */
+          hostent = malloc(sizeof(struct hostent));
+          if (hostent)
+            {
+              hostent->h_addr_list = malloc((naddrs + 1) * sizeof(char *));
+              if (hostent->h_addr_list)
+                {
+                  /* Fill in the hostent and return successfully. */
+                  hostent->h_name = hostname;
+                  hostent->h_aliases = aliases;
+                  hostent->h_addrtype = AF_INET;
+                  hostent->h_length = sizeof(struct in_addr);
+                  for (i = 0; i < naddrs; i++)
+                    hostent->h_addr_list[i] = (char *) &addrs[i];
+                  hostent->h_addr_list[naddrs] = NULL;
+                  *host = hostent;
+                  return ARES_SUCCESS;
+                }
+              free(hostent);
+            }
+          status = ARES_ENOMEM;
+        }
+     }
+  if (aliases)
+    {
+      for (i = 0; i < naliases; i++)
+        free(aliases[i]);
+      free(aliases);
+    }
+  free(addrs);
+  free(hostname);
+  return status;
+}