normalize crlf on some file types and no trailing whitespace on pas and dpr files

[lcore.git] / dnscore.pas

diff --git a/dnscore.pas b/dnscore.pas
old mode 100755 (executable)
new mode 100644 (file)
index ef4c2f1..08f99d1
--- a/dnscore.pas
+++ b/dnscore.pas
@@ -6,12 +6,12 @@
 {\r
 \r
   code wanting to use this dns system should act as follows (note: app\r
 {\r
 \r
   code wanting to use this dns system should act as follows (note: app\r

-  developers will probablly want to use dnsasync or dnssync or write a similar\r
-  wrapper unit of thier own).\r
+  developers will probably want to use dnsasync or dnssync or write a similar\r
+  wrapper unit of their own).\r

 \r
   for normal lookups call setstate_forward or setstate_reverse to set up the\r
   state, for more obscure lookups use setstate_request_init and fill in other\r
 \r
   for normal lookups call setstate_forward or setstate_reverse to set up the\r
   state, for more obscure lookups use setstate_request_init and fill in other\r

-  relavent state manually.\r
+  relevant state manually.\r

 \r
   call state_process which will do processing on the information in the state\r
   and return an action\r
 \r
   call state_process which will do processing on the information in the state\r
   and return an action\r


@@ -20,7 +20,7 @@
   action_sendpacket means that dnscore wants the code that calls it to send\r
   the packet in sendpacket/sendpacketlen and then start (or go back to) listening\r
   for\r
   action_sendpacket means that dnscore wants the code that calls it to send\r
   the packet in sendpacket/sendpacketlen and then start (or go back to) listening\r
   for\r

-  action_done means the request has completed (either suceeded or failed)\r
+  action_done means the request has completed (either succeeded or failed)\r

 \r
   callers should resend the last packet they tried to send if they have not\r
   been asked to send a new packet for more than some timeout value they choose.\r
 \r
   callers should resend the last packet they tried to send if they have not\r
   been asked to send a new packet for more than some timeout value they choose.\r


@@ -28,27 +28,27 @@
   when a packet is received the application should put the packet in\r
   recvbuf/recvbuflen , set state.parsepacket and call state_process again\r
 \r
   when a packet is received the application should put the packet in\r
   recvbuf/recvbuflen , set state.parsepacket and call state_process again\r
 \r

-  once the app gets action_done it can determine sucess or failure in the\r
+  once the app gets action_done it can determine success or failure in the\r

   following ways.\r
 \r
   on failure state.resultstr will be an empty string and state.resultbin will\r
   following ways.\r
 \r
   on failure state.resultstr will be an empty string and state.resultbin will\r

-  be zeroed out (easilly detected by the fact that it will have a family of 0)\r
+  be zeroed out (easily detected by the fact that it will have a family of 0)\r

 \r
   on success for a A or AAAA lookup state.resultstr will be an empty string\r
 \r
   on success for a A or AAAA lookup state.resultstr will be an empty string\r

-  and state.resultbin will contain the result (note: AAAA lookups require IPV6\r
+  and state.resultbin will contain the result (note: AAAA lookups require IPv6\r

   enabled).\r
 \r
   enabled).\r
 \r

-  if an A lookup fails and the code is built with ipv6 enabled then the code\r
+  if an A lookup fails and the code is built with IPv6 enabled then the code\r

   will return any AAAA records with the same name. The reverse does not apply\r
   will return any AAAA records with the same name. The reverse does not apply\r

-  so if an application preffers IPV6 but wants IPV4 results as well it must\r
-  check them seperately.\r
+  so if an application prefers IPv6 but wants IPv4 results as well it must\r
+  check them separately.\r

 \r
   on success for any other type of lookup state.resultstr will be an empty\r
 \r
   note the state contains ansistrings, setstate_init with a null name parameter\r
 \r
   on success for any other type of lookup state.resultstr will be an empty\r
 \r
   note the state contains ansistrings, setstate_init with a null name parameter\r

-  can be used to clean theese up if required.\r
+  can be used to clean these up if required.\r

 \r
 \r

-  callers may use setstate_failure to mark the state as failed themseleves\r
+  callers may use setstate_failure to mark the state as failed themselves\r

   before passing it on to other code, for example this may be done in the event\r
   of a timeout.\r
 }\r
   before passing it on to other code, for example this may be done in the event\r
   of a timeout.\r
 }\r


@@ -60,9 +60,9 @@ unit dnscore;
 \r
 interface\r
 \r
 \r
 interface\r
 \r

-uses binipstuff,classes,pgtypes;\r
+uses binipstuff,classes,pgtypes,lcorernd;\r

 \r
 \r

-var usewindns : boolean = {$ifdef win32}true{$else}false{$endif};\r
+var usewindns : boolean = {$ifdef mswindows}true{$else}false{$endif};\r

 {hint to users of this unit that they should use windows dns instead.\r
 May be disabled by applications if desired. (e.g. if setting a custom\r
 dnsserverlist).\r
 {hint to users of this unit that they should use windows dns instead.\r
 May be disabled by applications if desired. (e.g. if setting a custom\r
 dnsserverlist).\r


@@ -82,6 +82,11 @@ can be set by apps as desired
 }\r
 var useaf:integer = useaf_default;\r
 \r
 }\r
 var useaf:integer = useaf_default;\r
 \r

+{\r
+(temporarily) use a different nameserver, regardless of the dnsserverlist\r
+}\r
+var overridednsserver:ansistring;\r
+\r

 const\r
   maxnamelength=127;\r
   maxnamefieldlen=63;\r
 const\r
   maxnamelength=127;\r
   maxnamefieldlen=63;\r


@@ -93,13 +98,18 @@ const
   querytype_a=1;\r
   querytype_cname=5;\r
   querytype_aaaa=28;\r
   querytype_a=1;\r
   querytype_cname=5;\r
   querytype_aaaa=28;\r

+  querytype_a6=38;\r

   querytype_ptr=12;\r
   querytype_ns=2;\r
   querytype_soa=6;\r
   querytype_mx=15;\r
   querytype_ptr=12;\r
   querytype_ns=2;\r
   querytype_soa=6;\r
   querytype_mx=15;\r

-\r
-  maxrecursion=10;\r
-  maxrrofakind=20;\r
+  querytype_txt=16;\r
+  querytype_spf=99;\r
+  maxrecursion=50;\r
+  maxrrofakind=32;\r
+  {the maximum number of RR of a kind of purely an extra sanity check and could be omitted.\r
+  before, i set it to 20, but valid replies can have more. dnscore only does udp requests,\r
+  and ordinary DNS, so up to 512 bytes. the maximum number of A records that fits seems to be 29}\r

 \r
   retryafter=300000; //microseconds must be less than one second;\r
   timeoutlag=1000000000; // penalty value to be treated as lag in the event of a timeout (microseconds)\r
 \r
   retryafter=300000; //microseconds must be less than one second;\r
   timeoutlag=1000000000; // penalty value to be treated as lag in the event of a timeout (microseconds)\r


@@ -118,16 +128,16 @@ type
   tdnsstate=record\r
     id:word;\r
     recursioncount:integer;\r
   tdnsstate=record\r
     id:word;\r
     recursioncount:integer;\r

-    queryname:string;\r
+    queryname:ansistring;\r

     requesttype:word;\r
     parsepacket:boolean;\r
     requesttype:word;\r
     parsepacket:boolean;\r

-    resultstr:string;\r
+    resultstr:ansistring;\r

     resultbin:tbinip;\r
     resultlist:tbiniplist;\r
     resultaction:integer;\r
     numrr1:array[0..3] of integer;\r
     numrr2:integer;\r
     resultbin:tbinip;\r
     resultlist:tbiniplist;\r
     resultaction:integer;\r
     numrr1:array[0..3] of integer;\r
     numrr2:integer;\r

-    rrdata:string;\r
+    rrdata:ansistring;\r

     sendpacketlen:integer;\r
     sendpacket:tdnspacket;\r
     recvpacketlen:integer;\r
     sendpacketlen:integer;\r
     sendpacket:tdnspacket;\r
     recvpacketlen:integer;\r


@@ -152,72 +162,100 @@ type
   end;\r
 \r
 //commenting out functions from interface that do not have documented semantics\r
   end;\r
 \r
 //commenting out functions from interface that do not have documented semantics\r

-//and probablly should not be called from outside this unit, reenable them\r
+//and probably should not be called from outside this unit, reenable them\r

 //if you must but please document them at the same time --plugwash\r
 \r
 //function buildrequest(const name:string;var packet:tdnspacket;requesttype:word):integer;\r
 \r
 //returns the DNS name used to reverse look up an IP, such as 4.3.2.1.in-addr.arpa for 1.2.3.4\r
 //if you must but please document them at the same time --plugwash\r
 \r
 //function buildrequest(const name:string;var packet:tdnspacket;requesttype:word):integer;\r
 \r
 //returns the DNS name used to reverse look up an IP, such as 4.3.2.1.in-addr.arpa for 1.2.3.4\r

-function makereversename(const binip:tbinip):string;\r
+function makereversename(const binip:tbinip):ansistring;\r

 \r
 \r

-procedure setstate_request_init(const name:string;var state:tdnsstate);\r
+procedure setstate_request_init(const name:ansistring;var state:tdnsstate);\r

 \r
 \r

-//set up state for a foward lookup. A family value of AF_INET6 will give only\r
-//ipv6 results. Any other value will give ipv4 results in preference and ipv6\r
-//results if ipv4 results are not available;\r
-procedure setstate_forward(const name:string;var state:tdnsstate;family:integer);\r
+//set up state for a forward lookup. A family value of AF_INET6 will give only\r
+//ipv6 results. Any other value will give only ipv4 results\r
+procedure setstate_forward(const name:ansistring;var state:tdnsstate;family:integer);\r

 \r
 procedure setstate_reverse(const binip:tbinip;var state:tdnsstate);\r
 procedure setstate_failure(var state:tdnsstate);\r
 //procedure setstate_return(const rrp:trrpointer;len:integer;var state:tdnsstate);\r
 \r
 \r
 procedure setstate_reverse(const binip:tbinip;var state:tdnsstate);\r
 procedure setstate_failure(var state:tdnsstate);\r
 //procedure setstate_return(const rrp:trrpointer;len:integer;var state:tdnsstate);\r
 \r

+//for custom raw lookups such as TXT, as desired by the user\r
+procedure setstate_custom(const name:ansistring; requesttype:integer; var state:tdnsstate);\r

 \r
 procedure state_process(var state:tdnsstate);\r
 \r
 //function decodename(const packet:tdnspacket;len,start,recursion:integer;var numread:integer):string;\r
 \r
 \r
 procedure state_process(var state:tdnsstate);\r
 \r
 //function decodename(const packet:tdnspacket;len,start,recursion:integer;var numread:integer):string;\r
 \r

-//presumablly this is exported to allow more secure random functions\r
-//to be substituted?\r
-var randomfunction:function:integer;\r
-\r
-\r

 procedure populatednsserverlist;\r
 procedure cleardnsservercache;\r
 \r
 var\r
 procedure populatednsserverlist;\r
 procedure cleardnsservercache;\r
 \r
 var\r

-  dnsserverlist : tstringlist;\r
+  dnsserverlist : tbiniplist;\r
+  dnsserverlag:tlist;\r

 //  currentdnsserverno : integer;\r
 \r
 //  currentdnsserverno : integer;\r
 \r

-function getcurrentsystemnameserver(var id:integer) :string;\r
+\r
+//getcurrentsystemnameserver returns the nameserver the app should use and sets\r
+//id to the id of that nameserver. id should later be used to report how laggy\r
+//the servers response was and if it was timed out.\r
+function getcurrentsystemnameserver(var id:integer) :ansistring;\r
+function getcurrentsystemnameserverbin(var id:integer) :tbinip;\r
+procedure reportlag(id:integer;lag:integer); //lag should be in microseconds and should be -1 to report a timeout\r

 \r
 //var\r
 //  unixnameservercache:string;\r
 { $endif}\r
 \r
 \r
 \r
 //var\r
 //  unixnameservercache:string;\r
 { $endif}\r
 \r
 \r

-procedure reportlag(id:integer;lag:integer); //lag should be in microseconds and should be -1 to report a timeout\r
+{$ifdef ipv6}\r
+procedure initpreferredmode;\r
+\r

 var\r
 var\r

-  failurereason:string;\r
+  preferredmodeinited:boolean;\r
+\r
+{$endif}\r
+\r
+var\r
+  failurereason:ansistring;\r
+\r
+function getquerytype(s:ansistring):integer;\r

 \r
 implementation\r
 \r
 uses\r
 \r
 implementation\r
 \r
 uses\r

-  {$ifdef win32}\r
-    windows,\r
-  {$endif}\r
-\r
+  lcorelocalips,\r

   sysutils;\r
 \r
   sysutils;\r
 \r

-function buildrequest(const name:string;var packet:tdnspacket;requesttype:word):integer;\r
+\r
+\r
+function getquerytype(s:ansistring):integer;\r
+begin\r
+  s := uppercase(s);\r
+  result := 0;\r
+  if (s = 'A') then result := querytype_a else\r
+  if (s = 'CNAME') then result := querytype_cname else\r
+  if (s = 'AAAA') then result := querytype_aaaa else\r
+  if (s = 'PTR') then result := querytype_ptr else\r
+  if (s = 'NS') then result := querytype_ns else\r
+  if (s = 'MX') then result := querytype_mx else\r
+  if (s = 'A6') then result := querytype_a6 else\r
+  if (s = 'TXT') then result := querytype_txt else\r
+  if (s = 'SOA') then result := querytype_soa else\r
+  if (s = 'SPF') then result := querytype_spf;\r
+end;\r
+\r
+function buildrequest(const name:ansistring;var packet:tdnspacket;requesttype:word):integer;\r

 var\r
   a,b:integer;\r
 var\r
   a,b:integer;\r

-  s:string;\r
+  s:ansistring;\r

   arr:array[0..sizeof(packet)-1] of byte absolute packet;\r
 begin\r
  { writeln('buildrequest: name: ',name);}\r
   result := 0;\r
   fillchar(packet,sizeof(packet),0);\r
   arr:array[0..sizeof(packet)-1] of byte absolute packet;\r
 begin\r
  { writeln('buildrequest: name: ',name);}\r
   result := 0;\r
   fillchar(packet,sizeof(packet),0);\r

-  if assigned(randomfunction) then packet.id := (randomfunction and $ffff) else packet.id := random(65536);\r
+  packet.id := randominteger($10000);\r
+\r

   packet.flags := htons($0100);\r
   packet.rrcount[0] := htons($0001);\r
 \r
   packet.flags := htons($0100);\r
   packet.rrcount[0] := htons($0001);\r
 \r


@@ -252,9 +290,9 @@ begin
   arr[result-4] := requesttype shr 8;\r
 end;\r
 \r
   arr[result-4] := requesttype shr 8;\r
 end;\r
 \r

-function makereversename(const binip:tbinip):string;\r
+function makereversename(const binip:tbinip):ansistring;\r

 var\r
 var\r

-  name:string;\r
+  name:ansistring;\r

   a,b:integer;\r
 begin\r
   name := '';\r
   a,b:integer;\r
 begin\r
   name := '';\r


@@ -286,10 +324,10 @@ doesnt read beyond len.
 empty result + non null failurereason: failure\r
 empty result + null failurereason: internal use\r
 }\r
 empty result + non null failurereason: failure\r
 empty result + null failurereason: internal use\r
 }\r

-function decodename(const packet:tdnspacket;len,start,recursion:integer;var numread:integer):string;\r
+function decodename(const packet:tdnspacket;len,start,recursion:integer;var numread:integer):ansistring;\r

 var\r
   arr:array[0..sizeof(packet)-1] of byte absolute packet;\r
 var\r
   arr:array[0..sizeof(packet)-1] of byte absolute packet;\r

-  s:string;\r
+  s:ansistring;\r

   a,b:integer;\r
 begin\r
   numread := 0;\r
   a,b:integer;\r
 begin\r
   numread := 0;\r


@@ -330,7 +368,7 @@ begin
           failurereason := 'decoding name: got out of range2';\r
           exit;\r
         end;\r
           failurereason := 'decoding name: got out of range2';\r
           exit;\r
         end;\r

-        result := result + char(arr[a]);\r
+        result := result + ansichar(arr[a]);\r

       end;\r
       inc(numread,b+1);\r
 \r
       end;\r
       inc(numread,b+1);\r
 \r


@@ -348,6 +386,14 @@ end;
 \r
 {==============================================================================}\r
 \r
 \r
 {==============================================================================}\r
 \r

+function getrawfromrr(const rrp:trrpointer;len:integer):ansistring;\r
+begin\r
+  setlength(result,htons(trr(rrp.p^).datalen));\r
+  uniquestring(result);\r
+  move(trr(rrp.p^).data,result[1],length(result));\r
+end;\r
+\r
+\r

 function getipfromrr(const rrp:trrpointer;len:integer):tbinip;\r
 begin\r
   fillchar(result,sizeof(result),0);\r
 function getipfromrr(const rrp:trrpointer;len:integer):tbinip;\r
 begin\r
   fillchar(result,sizeof(result),0);\r


@@ -379,6 +425,16 @@ begin
     querytype_a{$ifdef ipv6},querytype_aaaa{$endif}: begin\r
       state.resultbin := getipfromrr(rrp,len);\r
     end;\r
     querytype_a{$ifdef ipv6},querytype_aaaa{$endif}: begin\r
       state.resultbin := getipfromrr(rrp,len);\r
     end;\r

+    querytype_txt:begin\r
+      {TXT returns a raw string}\r
+      state.resultstr := copy(getrawfromrr(rrp,len),2,9999);\r
+      fillchar(state.resultbin,sizeof(state.resultbin),0);\r
+    end;\r
+    querytype_mx:begin\r
+      {MX is a name after a 16 bits word}\r
+      state.resultstr := decodename(state.recvpacket,state.recvpacketlen,taddrint(rrp.p)-taddrint(@state.recvpacket)+12,0,a);\r
+      fillchar(state.resultbin,sizeof(state.resultbin),0);\r
+    end;\r

   else\r
     {other reply types (PTR, MX) return a hostname}\r
     state.resultstr := decodename(state.recvpacket,state.recvpacketlen,taddrint(rrp.p)-taddrint(@state.recvpacket)+10,0,a);\r
   else\r
     {other reply types (PTR, MX) return a hostname}\r
     state.resultstr := decodename(state.recvpacket,state.recvpacketlen,taddrint(rrp.p)-taddrint(@state.recvpacket)+10,0,a);\r


@@ -386,7 +442,7 @@ begin
   end;\r
 end;\r
 \r
   end;\r
 end;\r
 \r

-procedure setstate_request_init(const name:string;var state:tdnsstate);\r
+procedure setstate_request_init(const name:ansistring;var state:tdnsstate);\r

 begin\r
   {destroy things properly}\r
   state.resultstr := '';\r
 begin\r
   {destroy things properly}\r
   state.resultstr := '';\r


@@ -397,7 +453,7 @@ begin
   state.parsepacket := false;\r
 end;\r
 \r
   state.parsepacket := false;\r
 end;\r
 \r

-procedure setstate_forward(const name:string;var state:tdnsstate;family:integer);\r
+procedure setstate_forward(const name:ansistring;var state:tdnsstate;family:integer);\r

 begin\r
   setstate_request_init(name,state);\r
   state.forwardfamily := family;\r
 begin\r
   setstate_request_init(name,state);\r
   state.forwardfamily := family;\r


@@ -413,6 +469,13 @@ begin
   state.requesttype := querytype_ptr;\r
 end;\r
 \r
   state.requesttype := querytype_ptr;\r
 end;\r
 \r

+procedure setstate_custom(const name:ansistring; requesttype:integer; var state:tdnsstate);\r
+begin\r
+  setstate_request_init(name,state);\r
+  state.requesttype := requesttype;\r
+end;\r
+\r
+\r

 procedure setstate_failure(var state:tdnsstate);\r
 begin\r
   state.resultstr := '';\r
 procedure setstate_failure(var state:tdnsstate);\r
 begin\r
   state.resultstr := '';\r


@@ -442,7 +505,10 @@ begin
     state.numrr2 := 0;\r
     for a := 0 to 3 do begin\r
       state.numrr1[a] := htons(state.recvpacket.rrcount[a]);\r
     state.numrr2 := 0;\r
     for a := 0 to 3 do begin\r
       state.numrr1[a] := htons(state.recvpacket.rrcount[a]);\r

-      if state.numrr1[a] > maxrrofakind then goto failure;\r
+      if state.numrr1[a] > maxrrofakind then begin\r
+        failurereason := 'exceeded maximum RR of a kind';\r
+        goto failure;\r
+      end;\r

       inc(state.numrr2,state.numrr1[a]);\r
     end;\r
 \r
       inc(state.numrr2,state.numrr1[a]);\r
     end;\r
 \r


@@ -516,23 +582,7 @@ begin
 \r
     {no cnames found, no items of correct type found}\r
     if state.forwardfamily <> 0 then goto failure;\r
 \r
     {no cnames found, no items of correct type found}\r
     if state.forwardfamily <> 0 then goto failure;\r

-{$ifdef ipv6}\r
-    if (state.requesttype = querytype_a) then begin\r
-      {v6 only: in case of forward, look for AAAA in alternative section}\r
-      for a := state.numrr1[0]+state.numrr1[1]+state.numrr1[2] to (state.numrr2-1) do begin\r
-        rrptemp := @state.rrdata[1+a*sizeof(trrpointer)];\r
-        rrtemp := rrptemp.p;\r
-        b := rrptemp.len;\r
-        if rrtemp.requesttype = querytype_aaaa then begin\r
-          setstate_return(rrptemp^,b,state);\r
-          exit;\r
-        end;\r
-      end;\r
-      {no AAAA's found in alternative, do a recursive lookup for them}\r
-      state.requesttype := querytype_aaaa;\r
-      goto recursed;\r
-    end;\r
-{$endif}\r
+\r

     goto failure;\r
 recursed:\r
     {here it needs recursed lookup}\r
     goto failure;\r
 recursed:\r
     {here it needs recursed lookup}\r


@@ -547,7 +597,7 @@ recursed:
     goto failure;\r
   end;\r
 \r
     goto failure;\r
   end;\r
 \r

-  {do /ets/hosts lookup here}\r
+  {do /etc/hosts lookup here}\r

   state.sendpacketlen := buildrequest(state.queryname,state.sendpacket,state.requesttype);\r
   if state.sendpacketlen = 0 then begin\r
     failurereason := 'building request packet failed';\r
   state.sendpacketlen := buildrequest(state.queryname,state.sendpacket,state.requesttype);\r
   if state.sendpacketlen = 0 then begin\r
     failurereason := 'building request packet failed';\r


@@ -560,132 +610,59 @@ recursed:
 failure:\r
   setstate_failure(state);\r
 end;\r
 failure:\r
   setstate_failure(state);\r
 end;\r

-{$ifdef win32}\r
-  const\r
-    MAX_HOSTNAME_LEN = 132;\r
-    MAX_DOMAIN_NAME_LEN = 132;\r
-    MAX_SCOPE_ID_LEN = 260    ;\r
-    MAX_ADAPTER_NAME_LENGTH = 260;\r
-    MAX_ADAPTER_ADDRESS_LENGTH = 8;\r
-    MAX_ADAPTER_DESCRIPTION_LENGTH = 132;\r
-    ERROR_BUFFER_OVERFLOW = 111;\r
-    MIB_IF_TYPE_ETHERNET = 6;\r
-    MIB_IF_TYPE_TOKENRING = 9;\r
-    MIB_IF_TYPE_FDDI = 15;\r
-    MIB_IF_TYPE_PPP = 23;\r
-    MIB_IF_TYPE_LOOPBACK = 24;\r
-    MIB_IF_TYPE_SLIP = 28;\r
-\r
-\r
-  type\r
-    tip_addr_string=packed record\r
-      Next :pointer;\r
-      IpAddress : array[0..15] of char;\r
-      ipmask    : array[0..15] of char;\r
-      context   : dword;\r
-    end;\r
-    pip_addr_string=^tip_addr_string;\r
-    tFIXED_INFO=packed record\r
-       HostName         : array[0..MAX_HOSTNAME_LEN-1] of char;\r
-       DomainName       : array[0..MAX_DOMAIN_NAME_LEN-1] of char;\r
-       currentdnsserver : pip_addr_string;\r
-       dnsserverlist    : tip_addr_string;\r
-       nodetype         : longint;\r
-       ScopeId          : array[0..MAX_SCOPE_ID_LEN + 4] of char;\r
-       enablerouting    : longbool;\r
-       enableproxy      : longbool;\r
-       enabledns        : longbool;\r
-    end;\r
-    pFIXED_INFO=^tFIXED_INFO;\r

 \r
 \r

-  var\r
-    iphlpapi : thandle;\r
-    getnetworkparams : function(pFixedInfo : PFIXED_INFO;OutBufLen : plongint) : longint;stdcall;\r
-{$endif}\r
+\r

 procedure populatednsserverlist;\r
 var\r
 procedure populatednsserverlist;\r
 var\r

-  {$ifdef win32}\r
-    fixed_info : pfixed_info;\r
-    fixed_info_len : longint;\r
-    currentdnsserver : pip_addr_string;\r
-  {$else}\r
-    t:textfile;\r
-    s:string;\r
-    a:integer;\r
-  {$endif}\r
+  a:integer;\r

 begin\r
 begin\r

-  //result := '';\r
-  if assigned(dnsserverlist) then begin\r
-    dnsserverlist.clear;\r
+  if assigned(dnsserverlag) then begin\r
+    dnsserverlag.clear;\r

   end else begin\r
   end else begin\r

-    dnsserverlist := tstringlist.Create;\r
+    dnsserverlag := tlist.Create;\r

   end;\r
   end;\r

-  {$ifdef win32}\r
-    if iphlpapi=0 then iphlpapi := loadlibrary('iphlpapi.dll');\r
-    if not assigned(getnetworkparams) then @getnetworkparams := getprocaddress(iphlpapi,'GetNetworkParams');\r
-    if not assigned(getnetworkparams) then exit;\r
-    fixed_info_len := 0;\r
-    if GetNetworkParams(nil,@fixed_info_len)<>ERROR_BUFFER_OVERFLOW then exit;\r
-    //fixed_info_len :=sizeof(tfixed_info);\r
-    getmem(fixed_info,fixed_info_len);\r
-    if GetNetworkParams(fixed_info,@fixed_info_len)<>0 then begin\r
-      freemem(fixed_info);\r
-      exit;\r
-    end;\r
-    currentdnsserver := @(fixed_info.dnsserverlist);\r
-    while assigned(currentdnsserver) do begin\r
-      dnsserverlist.Add(currentdnsserver.IpAddress);\r
-      currentdnsserver := currentdnsserver.next;\r
-    end;\r
-    freemem(fixed_info);\r
-  {$else}\r
-    filemode := 0;\r
-    assignfile(t,'/etc/resolv.conf');\r
-    {$i-}reset(t);{$i+}\r
-    if ioresult <> 0 then exit;\r
-\r
-    while not eof(t) do begin\r
-      readln(t,s);\r
-      if not (copy(s,1,10) = 'nameserver') then continue;\r
-      s := copy(s,11,500);\r
-      while s <> '' do begin\r
-        if (s[1] = #32) or (s[1] = #9) then s := copy(s,2,500) else break;\r
-      end;\r
-      a := pos(' ',s);\r
-      if a <> 0 then s := copy(s,1,a-1);\r
-      a := pos(#9,s);\r
-      if a <> 0 then s := copy(s,1,a-1);\r
-      //result := s;\r
-      //if result <> '' then break;\r
-      dnsserverlist.Add(s);\r
-    end;\r
-    close(t);\r
-  {$endif}\r
+\r
+  dnsserverlist := getsystemdnsservers;\r
+  for a := biniplist_getcount(dnsserverlist)-1 downto 0 do dnsserverlag.Add(nil);\r

 end;\r
 \r
 procedure cleardnsservercache;\r
 begin\r
 end;\r
 \r
 procedure cleardnsservercache;\r
 begin\r

-  if assigned(dnsserverlist) then begin\r
-    dnsserverlist.destroy;\r
-    dnsserverlist := nil;\r
+  if assigned(dnsserverlag) then begin\r
+    dnsserverlag.destroy;\r
+    dnsserverlag := nil;\r
+    dnsserverlist := '';\r

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

-function getcurrentsystemnameserver(var id:integer):string;\r
+function getcurrentsystemnameserverbin(var id:integer):tbinip;\r

 var\r
   counter : integer;\r
 var\r
   counter : integer;\r

-\r

 begin\r
 begin\r

-  if not assigned(dnsserverlist) then populatednsserverlist;\r
-  if dnsserverlist.count=0 then raise exception.create('no dns servers availible');\r
-  id := 0;\r
-  if dnsserverlist.count >1 then begin\r
+  {override the name server choice here, instead of overriding it wherever it's called\r
+  setting ID to -1 causes it to be ignored in reportlag}\r
+  if (overridednsserver <> '') then begin\r
+    result := ipstrtobinf(overridednsserver);\r
+    if result.family <> 0 then begin\r
+      id := -1;\r
+      exit;\r
+    end;\r
+  end;\r

 \r
 \r

-    for counter := 1 to dnsserverlist.count-1 do begin\r
-      if taddrint(dnsserverlist.objects[counter]) < taddrint(dnsserverlist.objects[id]) then id := counter;\r
+  if not assigned(dnsserverlag) then populatednsserverlist;\r
+  if dnsserverlag.count=0 then raise exception.create('no dns servers available');\r
+  id := 0;\r
+  if dnsserverlag.count >1 then begin\r
+    for counter := dnsserverlag.count-1 downto 1 do begin\r
+      if taddrint(dnsserverlag[counter]) < taddrint(dnsserverlag[id]) then id := counter;\r

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

-  result := dnsserverlist[id]\r
+  result := biniplist_get(dnsserverlist,id);\r
+end;\r
+\r
+function getcurrentsystemnameserver(var id:integer):ansistring;\r
+begin\r
+  result := ipbintostr(getcurrentsystemnameserverbin(id));\r

 end;\r
 \r
 procedure reportlag(id:integer;lag:integer); //lag should be in microseconds and should be -1 to report a timeout\r
 end;\r
 \r
 procedure reportlag(id:integer;lag:integer); //lag should be in microseconds and should be -1 to report a timeout\r


@@ -693,16 +670,35 @@ var
   counter : integer;\r
   temp : integer;\r
 begin\r
   counter : integer;\r
   temp : integer;\r
 begin\r

-  if (id < 0) or (id >= dnsserverlist.count) then exit;\r
+  if (id < 0) or (id >= dnsserverlag.count) then exit;\r

   if lag = -1 then lag := timeoutlag;\r
   if lag = -1 then lag := timeoutlag;\r

-  for counter := 0 to dnsserverlist.count-1 do begin\r
-    temp := taddrint(dnsserverlist.objects[counter]) *15;\r
+  for counter := 0 to dnsserverlag.count-1 do begin\r
+    temp := taddrint(dnsserverlag[counter]) *15;\r

     if counter=id then temp := temp + lag;\r
     if counter=id then temp := temp + lag;\r

-    dnsserverlist.objects[counter] := tobject(temp div 16);\r
+    dnsserverlag[counter] := tobject(temp div 16);\r

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

+\r
+{$ifdef ipv6}\r
+\r
+procedure initpreferredmode;\r
+begin\r
+  if preferredmodeinited then exit;\r
+  if useaf <> useaf_default then exit;\r
+\r
+  if (have_ipv6_connectivity) then\r
+    useaf := useaf_preferv6\r
+  else\r
+    useaf := useaf_preferv4;\r
+\r
+  preferredmodeinited := true;\r
+end;\r
+\r
+{$endif}\r
+\r
+\r

 {  quick and dirty description of dns packet structure to aid writing and\r
    understanding of parser code, refer to appropriate RFCs for proper specs\r
 - all words are network order\r
 {  quick and dirty description of dns packet structure to aid writing and\r
    understanding of parser code, refer to appropriate RFCs for proper specs\r
 - all words are network order\r