hosts file support in the built in dns resolver

[lcore.git] / dnssync.pas

diff --git a/dnssync.pas b/dnssync.pas
index d037a68ea9cc350bee1ca33d95cbd95e770efcce..c2b74569366ed4dd9c60eb5f9df250b62b4fb986 100644 (file)
--- a/dnssync.pas
+++ b/dnssync.pas
@@ -13,7 +13,7 @@ interface
   uses\r
     dnscore,\r
     binipstuff,\r
   uses\r
     dnscore,\r
     binipstuff,\r

-    {$ifdef win32}\r
+    {$ifdef mswindows}\r

       winsock,\r
       windows,\r
     {$else}\r
       winsock,\r
       windows,\r
     {$else}\r


@@ -31,9 +31,9 @@ interface
 \r
 //convert a name to an IP\r
 //will return v4 or v6 depending on what seems favorable, or manual preference setting\r
 \r
 //convert a name to an IP\r
 //will return v4 or v6 depending on what seems favorable, or manual preference setting\r

-//on error the binip will have a family of 0 (other fiels are also currently\r
+//on error the binip will have a family of 0 (other fields are also currently\r

 //zeroed out but may be used for further error information in future)\r
 //zeroed out but may be used for further error information in future)\r

-//timeout is in miliseconds, it is ignored when using windows dns\r
+//timeout is in milliseconds, it is ignored when using windows dns\r

 function forwardlookup(name:ansistring;timeout:integer):tbinip;\r
 \r
 //convert a name to a list of all IP's returned\r
 function forwardlookup(name:ansistring;timeout:integer):tbinip;\r
 \r
 //convert a name to a list of all IP's returned\r


@@ -46,6 +46,8 @@ function forwardlookuplist(name:ansistring;timeout:integer):tbiniplist;
 //details as above\r
 function reverselookup(ip:tbinip;timeout:integer):ansistring;\r
 \r
 //details as above\r
 function reverselookup(ip:tbinip;timeout:integer):ansistring;\r
 \r

+//function that the app can use to know whether the builtin or system resolver is being used\r
+function willusebuiltindns_sync:boolean;\r

 \r
 \r
 const\r
 \r
 \r
 const\r


@@ -60,22 +62,41 @@ const
 \r
 implementation\r
 \r
 \r
 implementation\r
 \r

-{$ifdef win32}\r
+{$ifdef mswindows}\r

   uses dnswin;\r
 {$endif}\r
 \r
 \r
   uses dnswin;\r
 {$endif}\r
 \r
 \r

-{$ifndef win32}\r
+{$ifndef mswindows}\r

 {$define syncdnscore}\r
 {$endif}\r
 \r
 {$i unixstuff.inc}\r
 \r
 {$define syncdnscore}\r
 {$endif}\r
 \r
 {$i unixstuff.inc}\r
 \r

+type tdnsstatearr=array[0..numsock-1] of tdnsstate;\r
+\r
+\r
+function willusebuiltindns_sync:boolean;\r
+begin\r
+  result := false;\r
+  {$ifdef mswindows}\r
+  if usewindns and (overridednsserver = '') and not (hostsfile_disabled or hostsfile_onlylocalhost) then begin\r
+    //\r
+  end else\r
+  {$endif}\r
+  begin\r
+    {$ifdef syncdnscore}\r
+    result := true;\r
+    {$endif}\r
+  end;\r
+end;\r
+\r
+\r

 \r
 {$ifdef syncdnscore}\r
 \r
 \r
 \r
 {$ifdef syncdnscore}\r
 \r
 \r

-{$ifdef win32}\r
+{$ifdef mswindows}\r

   const\r
     winsocket = 'wsock32.dll';\r
   function sendto(s: TSocket; const Buf; len, flags: Integer; var addrto: TinetSockAddrV; tolen: Integer): Integer; stdcall; external    winsocket name 'sendto';\r
   const\r
     winsocket = 'wsock32.dll';\r
   function sendto(s: TSocket; const Buf; len, flags: Integer; var addrto: TinetSockAddrV; tolen: Integer): Integer; stdcall; external    winsocket name 'sendto';\r


@@ -86,21 +107,18 @@ implementation
 \r
 \r
 function getts:integer;\r
 \r
 \r
 function getts:integer;\r

-{$ifdef win32}\r
+{$ifdef mswindows}\r

 begin\r
   result := GetTickCount and tsmask;\r
 {$else}\r
 var\r
   temp:ttimeval;\r
 begin\r
 begin\r
   result := GetTickCount and tsmask;\r
 {$else}\r
 var\r
   temp:ttimeval;\r
 begin\r

-  gettimeofday(temp);\r
+  gettimemonotonic(temp);\r

   result := ((temp.tv_usec div 1000) + (temp.tv_sec * 1000)) and tsmask;\r
 {$endif}\r
 end;\r
 \r
   result := ((temp.tv_usec div 1000) + (temp.tv_sec * 1000)) and tsmask;\r
 {$endif}\r
 end;\r
 \r

-\r
-type tdnsstatearr=array[0..numsock-1] of tdnsstate;\r
-\r

 procedure resolveloop(timeout:integer;var state:tdnsstatearr;numsockused:integer);\r
 var\r
   selectresult   : integer;\r
 procedure resolveloop(timeout:integer;var state:tdnsstatearr;numsockused:integer);\r
 var\r
   selectresult   : integer;\r


@@ -119,7 +137,7 @@ var
   a,b:integer;\r
 \r
   Src    : TInetSockAddrV;\r
   a,b:integer;\r
 \r
   Src    : TInetSockAddrV;\r

-  Srcx   : {$ifdef win32}sockaddr_in{$else}TInetSockAddrV{$endif} absolute Src;\r
+  Srcx   : {$ifdef mswindows}sockaddr_in{$else}TInetSockAddrV{$endif} absolute Src;\r

   SrcLen : Integer;\r
   fromip:tbinip;\r
   fromport:ansistring;\r
   SrcLen : Integer;\r
   fromip:tbinip;\r
   fromport:ansistring;\r


@@ -134,7 +152,8 @@ procedure setupsocket;
 var\r
   inAddrtemp : TInetSockAddrV;\r
   biniptemp:tbinip;\r
 var\r
   inAddrtemp : TInetSockAddrV;\r
   biniptemp:tbinip;\r

-  a:integer;\r
+  a,retrycount,porttemp:integer;\r
+  bindresult:boolean;\r

 begin\r
   biniptemp := getcurrentsystemnameserverbin(id);\r
   //must get the DNS server here so we know to init v4 or v6\r
 begin\r
   biniptemp := getcurrentsystemnameserverbin(id);\r
   //must get the DNS server here so we know to init v4 or v6\r


@@ -143,12 +162,23 @@ begin
 \r
 \r
   for a := 0 to numsockused-1 do begin\r
 \r
 \r
   for a := 0 to numsockused-1 do begin\r

-    makeinaddrv(biniptemp,inttostr( 1024 + randominteger(65536 - 1024) ),inaddrtemp);\r
+    retrycount := 5;\r
+    repeat\r
+      if (retrycount <= 1) then begin\r
+        porttemp := 0; //for the last attempt let the OS decide\r
+      end else begin\r
+        porttemp := 1024 + randominteger(65536 - 1024);\r
+      end;\r

 \r
 \r

-    fd[a] := Socket(biniptemp.family,SOCK_DGRAM,0);\r
+      makeinaddrv(biniptemp,inttostr( porttemp ),inaddrtemp);\r

 \r
 \r

-    If {$ifndef win32}Not{$endif} Bind(fd[a],inAddrtemp,inaddrsize(inaddrtemp)) Then begin\r
-      {$ifdef win32}\r
+      fd[a] := Socket(biniptemp.family,SOCK_DGRAM,0);\r
+      bindresult := {$ifdef mswindows}Not{$endif} Bind(fd[a],inAddrtemp,inaddrsize(inaddrtemp));\r
+      dec(retrycount);\r
+    until (retrycount <= 0) or (bindresult);\r
+\r
+    If (not bindresult) Then begin\r
+      {$ifdef mswindows}\r

         raise Exception.create('unable to bind '+inttostr(WSAGetLastError));\r
       {$else}\r
         raise Exception.create('unable to bind '+inttostr(socketError));\r
         raise Exception.create('unable to bind '+inttostr(WSAGetLastError));\r
       {$else}\r
         raise Exception.create('unable to bind '+inttostr(socketError));\r


@@ -176,7 +206,7 @@ begin
 \r
   ip := getcurrentsystemnameserverbin(id);\r
 \r
 \r
   ip := getcurrentsystemnameserverbin(id);\r
 \r

-  {$ifdef ipv6}{$ifdef win32}\r
+  {$ifdef ipv6}{$ifdef mswindows}\r

   if toaddr[socknum].family = AF_INET6 then if (useaf = 0) then useaf := useaf_preferv6;\r
   {$endif}{$endif}\r
 \r
   if toaddr[socknum].family = AF_INET6 then if (useaf = 0) then useaf := useaf_preferv6;\r
   {$endif}{$endif}\r
 \r


@@ -246,7 +276,7 @@ begin
       selecttimeout.tv_sec := 0;\r
       selecttimeout.tv_usec := retryafter;\r
     end;\r
       selecttimeout.tv_sec := 0;\r
       selecttimeout.tv_usec := retryafter;\r
     end;\r

-    //find the highest of the used fd's\r
+    //find the highest of the used fds\r

     b := 0;\r
     for socknum := numsockused-1 downto 0 do if fd[socknum] > b then b := fd[socknum];\r
     selectresult := select(b+1,@fds,nil,nil,@selecttimeout);\r
     b := 0;\r
     for socknum := numsockused-1 downto 0 do if fd[socknum] > b then b := fd[socknum];\r
     selectresult := select(b+1,@fds,nil,nil,@selecttimeout);\r


@@ -317,8 +347,8 @@ begin
     exit; //it was an IP address, no need for dns\r
   end;\r
 \r
     exit; //it was an IP address, no need for dns\r
   end;\r
 \r

-  {$ifdef win32}\r
-  if usewindns then begin\r
+  {$ifdef mswindows}\r
+  if usewindns and (overridednsserver = '') and not (hostsfile_disabled or hostsfile_onlylocalhost) then begin\r

     if (useaf = useaf_v4) then a := af_inet else if (useaf = useaf_v6) then a := af_inet6 else a := 0;\r
     result := winforwardlookuplist(name,a,dummy);\r
     {$ifdef ipv6}\r
     if (useaf = useaf_v4) then a := af_inet else if (useaf = useaf_v6) then a := af_inet6 else a := 0;\r
     result := winforwardlookuplist(name,a,dummy);\r
     {$ifdef ipv6}\r


@@ -343,6 +373,15 @@ begin
   {$ifdef syncdnscore}\r
     {$ifdef ipv6}initpreferredmode;{$endif}\r
 \r
   {$ifdef syncdnscore}\r
     {$ifdef ipv6}initpreferredmode;{$endif}\r
 \r

+    if ((overridednsserver = '') or hostsfile_alsocustomserver) and (not hostsfile_disabled) then begin\r
+      //try a hosts file lookup\r
+      l := hostsfile_forwardlookuplist(name);\r
+      if (biniplist_getcount(l) > 0) then begin\r
+        result := l;\r
+        exit;\r
+      end;\r
+    end;\r
+\r

     numsockused := 0;\r
 \r
     result := biniplist_new;\r
     numsockused := 0;\r
 \r
     result := biniplist_new;\r


@@ -370,7 +409,9 @@ begin
       biniplist_addlist(result,state[1].resultlist);\r
     {$endif}\r
     end;\r
       biniplist_addlist(result,state[1].resultlist);\r
     {$endif}\r
     end;\r

-    {$endif}\r
+  {$else}\r
+    result := biniplist_new;\r
+  {$endif}\r

   end;\r
 end;\r
 \r
   end;\r
 end;\r
 \r


@@ -388,21 +429,30 @@ var
   numsockused:integer;\r
   state:tdnsstatearr;\r
 begin\r
   numsockused:integer;\r
   state:tdnsstatearr;\r
 begin\r

-  {$ifdef win32}\r
-    if usewindns then begin\r
+  {$ifdef mswindows}\r
+    if usewindns and (overridednsserver = '') and not (hostsfile_disabled or hostsfile_onlylocalhost) then begin\r

       result := winreverselookup(ip,dummy);\r
       exit;\r
     end;\r
   {$endif}\r
   {$ifdef syncdnscore}\r
       result := winreverselookup(ip,dummy);\r
       exit;\r
     end;\r
   {$endif}\r
   {$ifdef syncdnscore}\r

+\r
+  if ((overridednsserver = '') or hostsfile_alsocustomserver) and (not hostsfile_disabled) then begin\r
+    //try a hosts file lookup\r
+    result := hostsfile_reverselookup(ip);\r
+    if (result <> '') then exit;\r
+  end;\r
+\r

   setstate_reverse(ip,state[0]);\r
   numsockused := 1;\r
   resolveloop(timeout,state,numsockused);\r
   result := state[0].resultstr;\r
   setstate_reverse(ip,state[0]);\r
   numsockused := 1;\r
   resolveloop(timeout,state,numsockused);\r
   result := state[0].resultstr;\r

+  {$else}\r
+  result := '';\r

   {$endif}\r
 end;\r
 \r
   {$endif}\r
 end;\r
 \r

-{$ifdef win32}\r
+{$ifdef mswindows}\r

   var\r
     wsadata : twsadata;\r
 \r
   var\r
     wsadata : twsadata;\r
 \r