Dominick Meglio added ares_parse_aaaa_reply.c and did various adjustments. The

first little steps towards IPv6 support!

ares/CHANGES

@@ -1,5 +1,10 @@
   Changelog for the c-ares project
 
+* March 11, 2005
+
+- Dominick Meglio added ares_parse_aaaa_reply.c and did various
+  adjustments. The first little steps towards IPv6 support!
+
 * November 7
 
 - Fixed the VC project and makefile to use ares_cancel and ares_version

ares/Makefile.inc

@@ -3,7 +3,8 @@ ares__close_sockets.c ares_free_string.c ares_search.c ares__get_hostent.c \
 ares_gethostbyaddr.c ares_send.c ares__read_line.c ares_gethostbyname.c	   \
 ares_strerror.c ares_cancel.c ares_init.c ares_timeout.c ares_destroy.c	   \
 ares_mkquery.c ares_version.c ares_expand_name.c ares_parse_a_reply.c	   \
-windows_port.c ares_expand_string.c ares_parse_ptr_reply.c
+windows_port.c ares_expand_string.c ares_parse_ptr_reply.c                 \
+ares_parse_aaaa_reply.c
 
 HHEADERS = ares.h ares_private.h setup.h ares_dns.h ares_version.h nameser.h
 
@@ -12,4 +13,4 @@ MANPAGES= ares_destroy.3 ares_expand_name.3 ares_expand_string.3 ares_fds.3 \
  ares_gethostbyname.3 ares_init.3 ares_init_options.3 ares_mkquery.3	    \
  ares_parse_a_reply.3 ares_parse_ptr_reply.3 ares_process.3		    \
  ares_query.3 ares_search.3 ares_send.3 ares_strerror.3 ares_timeout.3	    \
- ares_version.3 ares_cancel.3
+ ares_version.3 ares_cancel.3

ares/acinclude.m4

@@ -99,3 +99,52 @@ AC_DEFUN([CURL_CC_DEBUG_OPTS],
 
 ]) dnl end of AC_DEFUN()
 
+
+dnl This macro determines if the specified struct exists in the specified file
+dnl Syntax:
+dnl CARES_CHECK_STRUCT(headers, struct name, if found, [if not found])
+
+AC_DEFUN([CARES_CHECK_STRUCT], [
+  AC_MSG_CHECKING([for struct $2])
+  AC_TRY_COMPILE([$1], 
+    [
+      struct $2 struct_instance;
+    ], ac_struct="yes", ac_found="no")
+  if test "$ac_struct" = "yes" ; then
+    AC_MSG_RESULT(yes)
+    $3
+  else
+    AC_MSG_RESULT(no)
+    $4
+  fi
+])
+
+dnl This macro determines if the specified constant exists in the specified file
+dnl Syntax:
+dnl CARES_CHECK_CONSTANT(headers, constant name, if found, [if not found])
+
+AC_DEFUN([CARES_CHECK_CONSTANT], [
+  AC_MSG_CHECKING([for $2])
+  AC_TRY_RUN( 
+    [
+      $1
+
+      int main()
+      {
+        #ifdef $2
+          return 0;
+        #else
+          return 1;
+        #endif
+      }
+    ], ac_constant="yes", ac_constant="no")
+  if test "$ac_constant" = "yes" ; then
+    AC_MSG_RESULT(yes)
+    $3
+  else
+    AC_MSG_RESULT(no)
+    $4
+  fi
+])
+
+

ares/ares.h

@@ -137,12 +137,13 @@ int ares_expand_string(const unsigned char *encoded, const unsigned char *abuf,
                      int alen, unsigned char **s, long *enclen);
 int ares_parse_a_reply(const unsigned char *abuf, int alen,
                        struct hostent **host);
+int ares_parse_aaaa_reply(const unsigned char *abuf, int alen,
+                       struct hostent **host);
 int ares_parse_ptr_reply(const unsigned char *abuf, int alen, const void *addr,
                          int addrlen, int family, struct hostent **host);
 void ares_free_string(void *str);
 void ares_free_hostent(struct hostent *host);
 const char *ares_strerror(int code);
-void ares_free_errmem(char *mem);
 
 #ifdef  __cplusplus
 }

ares/ares_parse_aaaa_reply.c

@@ -0,0 +1,173 @@
+/* Copyright 2005 Dominick Meglio
+ *
+ * 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 "setup.h"
+#include <sys/types.h>
+
+#if defined(WIN32) && !defined(WATT32)
+#include "nameser.h"
+#else
+#include <sys/socket.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+#include <netdb.h>
+#include <arpa/nameser.h>
+#endif
+
+#include <stdlib.h>
+#include <string.h>
+#include "ares.h"
+#include "ares_dns.h"
+#include "ares_private.h"
+
+int ares_parse_aaaa_reply(const unsigned char *abuf, int alen,
+                       struct hostent **host)
+{
+  unsigned int qdcount, ancount;
+  int status, i, rr_type, rr_class, rr_len, naddrs;
+  int naliases;
+  long len;
+  const unsigned char *aptr;
+  char *hostname, *rr_name, *rr_data, **aliases;
+  struct in6_addr *addrs;
+  struct hostent *hostent;
+
+  /* Set *host to NULL for all failure cases. */
+  *host = NULL;
+
+  /* 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(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;
+
+  /* Allocate addresses and aliases; ancount gives an upper bound for both. */
+  addrs = malloc(ancount * sizeof(struct in6_addr));
+  if (!addrs)
+    {
+      free(hostname);
+      return ARES_ENOMEM;
+    }
+  aliases = malloc((ancount + 1) * sizeof(char *));
+  if (!aliases)
+    {
+      free(hostname);
+      free(addrs);
+      return ARES_ENOMEM;
+    }
+  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(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);
+      aptr += RRFIXEDSZ;
+
+      if (rr_class == C_IN && rr_type == T_AAAA
+          && rr_len == sizeof(struct in6_addr)
+          && strcasecmp(rr_name, hostname) == 0)
+        {
+          memcpy(&addrs[naddrs], aptr, sizeof(struct in6_addr));
+          naddrs++;
+          status = ARES_SUCCESS;
+        }
+
+      if (rr_class == C_IN && rr_type == T_CNAME)
+        {
+          /* Record the RR name as an alias. */
+          aliases[naliases] = rr_name;
+          naliases++;
+
+          /* Decode the RR data and replace the hostname with it. */
+          status = ares_expand_name(aptr, abuf, alen, &rr_data, &len);
+          if (status != ARES_SUCCESS)
+            break;
+          free(hostname);
+          hostname = rr_data;
+        }
+      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.  Allocate memory to build the host entry. */
+      aliases[naliases] = NULL;
+      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_INET6;
+              hostent->h_length = sizeof(struct in6_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;
+    }
+  for (i = 0; i < naliases; i++)
+    free(aliases[i]);
+  free(aliases);
+  free(addrs);
+  free(hostname);
+  return status;
+}

ares/configure.ac

@@ -63,4 +63,32 @@ AC_CHECK_HEADERS(
        sys/socket.h \
        )
 
+dnl check for AF_INET6
+CARES_CHECK_CONSTANT(
+  [
+    #include <sys/types.h>
+    #include <sys/socket.h>
+  ], [PF_INET6], 
+     AC_DEFINE_UNQUOTED(HAVE_PF_INET6,1,[Define to 1 if you have PF_INET6.])
+)
+
+dnl check for PF_INET6
+CARES_CHECK_CONSTANT(
+  [
+    #include <sys/types.h>
+    #include <sys/socket.h>
+  ], [AF_INET6], 
+     AC_DEFINE_UNQUOTED(HAVE_AF_INET6,1,[Define to 1 if you have AF_INET6.])
+)
+
+
+dnl check for the in6_addr structure
+CARES_CHECK_STRUCT(
+  [
+    #include <sys/types.h>
+    #include <netinet/in.h>
+  ], [in6_addr], 
+     AC_DEFINE_UNQUOTED(HAVE_STRUCT_IN6_ADDR,1,[Define to 1 if you have struct in6_addr.])
+)
+
 AC_OUTPUT(Makefile)

ares/setup.h

@@ -1,7 +1,7 @@
 #ifndef ARES_SETUP_H
 #define ARES_SETUP_H
 
-/* Copyright (C) 2004 by Daniel Stenberg et al
+/* Copyright (C) 2004 - 2005 by Daniel Stenberg et al
  *
  * Permission to use, copy, modify, and distribute this software and its
  * documentation for any purpose and without fee is hereby granted, provided
@@ -45,11 +45,11 @@ typedef int ares_socket_t;
 /* Assume a few thing unless they're set by configure
  */
 #if !defined(HAVE_SYS_TIME_H) && !defined(_MSC_VER)
-#define HAVE_SYS_TIME_H  
+#define HAVE_SYS_TIME_H
 #endif
 
 #if !defined(HAVE_UNISTD_H) && !defined(_MSC_VER)
-#define HAVE_UNISTD_H 
+#define HAVE_UNISTD_H
 #endif
 
 #if !defined(HAVE_SYS_UIO_H) && !defined(WIN32) && !defined(MSDOS)
@@ -69,4 +69,24 @@ int ares_strcasecmp(const char *s1, const char *s2);
 #define strcasecmp(a,b) ares_strcasecmp(a,b)
 #endif
 
+/* IPv6 compatibility */
+#if !defined(HAVE_AF_INET6)
+#if defined(HAVE_PF_INET6)
+#define AF_INET6 PF_INET6
+#else
+#define AF_INET6 AF_MAX+1
+#endif
+#endif
+
+#ifndef HAVE_PF_INET6
+#define PF_INET6 AF_INET6
+#endif
+
+#ifndef HAVE_STRUCT_IN6_ADDR
+struct in6_addr
+{
+  unsigned char s6_addr[16];
+};
+#endif
+
 #endif /* ARES_SETUP_H */