X-Git-Url: http://www.lcore.org/git/lcore.git/blobdiff_plain/055fa6bf18e0733d1bf2f97075d6bb33c76e72b5..1272fe8df1c3cc91ea478e2d2d44a0ec4c80f57b:/dnscore.pas
diff --git a/dnscore.pas b/dnscore.pas
index 4cb52e2..3a9596f 100644
--- a/dnscore.pas
+++ b/dnscore.pas
@@ -28,7 +28,7 @@
when a packet is received the application should put the packet in
recvbuf/recvbuflen , set state.parsepacket and call state_process again
- once the app gets action_done it can determine sucess or failure in the
+ once the app gets action_done it can determine success or failure in the
following ways.
on failure state.resultstr will be an empty string and state.resultbin will
@@ -85,7 +85,7 @@ var useaf:integer = useaf_default;
{
(temporarily) use a different nameserver, regardless of the dnsserverlist
}
-var overridednsserver:string;
+var overridednsserver:ansistring;
const
maxnamelength=127;
@@ -106,7 +106,10 @@ const
querytype_txt=16;
querytype_spf=99;
maxrecursion=50;
- maxrrofakind=20;
+ maxrrofakind=32;
+ {the maximum number of RR of a kind of purely an extra sanity check and could be omitted.
+ before, i set it to 20, but valid replies can have more. dnscore only does udp requests,
+ and ordinary DNS, so up to 512 bytes. the maximum number of A records that fits seems to be 29}
retryafter=300000; //microseconds must be less than one second;
timeoutlag=1000000000; // penalty value to be treated as lag in the event of a timeout (microseconds)
@@ -125,16 +128,16 @@ type
tdnsstate=record
id:word;
recursioncount:integer;
- queryname:string;
+ queryname:ansistring;
requesttype:word;
parsepacket:boolean;
- resultstr:string;
+ resultstr:ansistring;
resultbin:tbinip;
resultlist:tbiniplist;
resultaction:integer;
numrr1:array[0..3] of integer;
numrr2:integer;
- rrdata:string;
+ rrdata:ansistring;
sendpacketlen:integer;
sendpacket:tdnspacket;
recvpacketlen:integer;
@@ -165,20 +168,20 @@ type
//function buildrequest(const name:string;var packet:tdnspacket;requesttype:word):integer;
//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
-function makereversename(const binip:tbinip):string;
+function makereversename(const binip:tbinip):ansistring;
-procedure setstate_request_init(const name:string;var state:tdnsstate);
+procedure setstate_request_init(const name:ansistring;var state:tdnsstate);
//set up state for a foward lookup. A family value of AF_INET6 will give only
//ipv6 results. Any other value will give only ipv4 results
-procedure setstate_forward(const name:string;var state:tdnsstate;family:integer);
+procedure setstate_forward(const name:ansistring;var state:tdnsstate;family:integer);
procedure setstate_reverse(const binip:tbinip;var state:tdnsstate);
procedure setstate_failure(var state:tdnsstate);
//procedure setstate_return(const rrp:trrpointer;len:integer;var state:tdnsstate);
//for custom raw lookups such as TXT, as desired by the user
-procedure setstate_custom(const name:string; requesttype:integer; var state:tdnsstate);
+procedure setstate_custom(const name:ansistring; requesttype:integer; var state:tdnsstate);
procedure state_process(var state:tdnsstate);
@@ -188,14 +191,16 @@ procedure populatednsserverlist;
procedure cleardnsservercache;
var
- dnsserverlist : tstringlist;
+ dnsserverlist : tbiniplist;
+ dnsserverlag:tlist;
// currentdnsserverno : integer;
//getcurrentsystemnameserver returns the nameserver the app should use and sets
//id to the id of that nameserver. id should later be used to report how laggy
//the servers response was and if it was timed out.
-function getcurrentsystemnameserver(var id:integer) :string;
+function getcurrentsystemnameserver(var id:integer) :ansistring;
+function getcurrentsystemnameserverbin(var id:integer) :tbinip;
procedure reportlag(id:integer;lag:integer); //lag should be in microseconds and should be -1 to report a timeout
//var
@@ -204,7 +209,6 @@ procedure reportlag(id:integer;lag:integer); //lag should be in microseconds and
{$ifdef ipv6}
-function getv6localips:tbiniplist;
procedure initpreferredmode;
var
@@ -213,22 +217,19 @@ var
{$endif}
var
- failurereason:string;
+ failurereason:ansistring;
-function getquerytype(s:string):integer;
+function getquerytype(s:ansistring):integer;
implementation
uses
- {$ifdef win32}
- windows,
- {$endif}
-
+ lcorelocalips,
sysutils;
-function getquerytype(s:string):integer;
+function getquerytype(s:ansistring):integer;
begin
s := uppercase(s);
result := 0;
@@ -244,10 +245,10 @@ begin
if (s = 'SPF') then result := querytype_spf;
end;
-function buildrequest(const name:string;var packet:tdnspacket;requesttype:word):integer;
+function buildrequest(const name:ansistring;var packet:tdnspacket;requesttype:word):integer;
var
a,b:integer;
- s:string;
+ s:ansistring;
arr:array[0..sizeof(packet)-1] of byte absolute packet;
begin
{ writeln('buildrequest: name: ',name);}
@@ -289,9 +290,9 @@ begin
arr[result-4] := requesttype shr 8;
end;
-function makereversename(const binip:tbinip):string;
+function makereversename(const binip:tbinip):ansistring;
var
- name:string;
+ name:ansistring;
a,b:integer;
begin
name := '';
@@ -323,10 +324,10 @@ doesnt read beyond len.
empty result + non null failurereason: failure
empty result + null failurereason: internal use
}
-function decodename(const packet:tdnspacket;len,start,recursion:integer;var numread:integer):string;
+function decodename(const packet:tdnspacket;len,start,recursion:integer;var numread:integer):ansistring;
var
arr:array[0..sizeof(packet)-1] of byte absolute packet;
- s:string;
+ s:ansistring;
a,b:integer;
begin
numread := 0;
@@ -367,7 +368,7 @@ begin
failurereason := 'decoding name: got out of range2';
exit;
end;
- result := result + char(arr[a]);
+ result := result + ansichar(arr[a]);
end;
inc(numread,b+1);
@@ -385,7 +386,7 @@ end;
{==============================================================================}
-function getrawfromrr(const rrp:trrpointer;len:integer):string;
+function getrawfromrr(const rrp:trrpointer;len:integer):ansistring;
begin
setlength(result,htons(trr(rrp.p^).datalen));
uniquestring(result);
@@ -441,7 +442,7 @@ begin
end;
end;
-procedure setstate_request_init(const name:string;var state:tdnsstate);
+procedure setstate_request_init(const name:ansistring;var state:tdnsstate);
begin
{destroy things properly}
state.resultstr := '';
@@ -452,7 +453,7 @@ begin
state.parsepacket := false;
end;
-procedure setstate_forward(const name:string;var state:tdnsstate;family:integer);
+procedure setstate_forward(const name:ansistring;var state:tdnsstate;family:integer);
begin
setstate_request_init(name,state);
state.forwardfamily := family;
@@ -468,7 +469,7 @@ begin
state.requesttype := querytype_ptr;
end;
-procedure setstate_custom(const name:string; requesttype:integer; var state:tdnsstate);
+procedure setstate_custom(const name:ansistring; requesttype:integer; var state:tdnsstate);
begin
setstate_request_init(name,state);
state.requesttype := requesttype;
@@ -504,7 +505,10 @@ begin
state.numrr2 := 0;
for a := 0 to 3 do begin
state.numrr1[a] := htons(state.recvpacket.rrcount[a]);
- if state.numrr1[a] > maxrrofakind then goto failure;
+ if state.numrr1[a] > maxrrofakind then begin
+ failurereason := 'exceeded maximum RR of a kind';
+ goto failure;
+ end;
inc(state.numrr2,state.numrr1[a]);
end;
@@ -606,132 +610,59 @@ recursed:
failure:
setstate_failure(state);
end;
-{$ifdef win32}
- const
- MAX_HOSTNAME_LEN = 132;
- MAX_DOMAIN_NAME_LEN = 132;
- MAX_SCOPE_ID_LEN = 260 ;
- MAX_ADAPTER_NAME_LENGTH = 260;
- MAX_ADAPTER_ADDRESS_LENGTH = 8;
- MAX_ADAPTER_DESCRIPTION_LENGTH = 132;
- ERROR_BUFFER_OVERFLOW = 111;
- MIB_IF_TYPE_ETHERNET = 6;
- MIB_IF_TYPE_TOKENRING = 9;
- MIB_IF_TYPE_FDDI = 15;
- MIB_IF_TYPE_PPP = 23;
- MIB_IF_TYPE_LOOPBACK = 24;
- MIB_IF_TYPE_SLIP = 28;
-
-
- type
- tip_addr_string=packed record
- Next :pointer;
- IpAddress : array[0..15] of char;
- ipmask : array[0..15] of char;
- context : dword;
- end;
- pip_addr_string=^tip_addr_string;
- tFIXED_INFO=packed record
- HostName : array[0..MAX_HOSTNAME_LEN-1] of char;
- DomainName : array[0..MAX_DOMAIN_NAME_LEN-1] of char;
- currentdnsserver : pip_addr_string;
- dnsserverlist : tip_addr_string;
- nodetype : longint;
- ScopeId : array[0..MAX_SCOPE_ID_LEN + 4] of char;
- enablerouting : longbool;
- enableproxy : longbool;
- enabledns : longbool;
- end;
- pFIXED_INFO=^tFIXED_INFO;
- var
- iphlpapi : thandle;
- getnetworkparams : function(pFixedInfo : PFIXED_INFO;OutBufLen : plongint) : longint;stdcall;
-{$endif}
+
procedure populatednsserverlist;
var
- {$ifdef win32}
- fixed_info : pfixed_info;
- fixed_info_len : longint;
- currentdnsserver : pip_addr_string;
- {$else}
- t:textfile;
- s:string;
- a:integer;
- {$endif}
+ a:integer;
begin
- //result := '';
- if assigned(dnsserverlist) then begin
- dnsserverlist.clear;
+ if assigned(dnsserverlag) then begin
+ dnsserverlag.clear;
end else begin
- dnsserverlist := tstringlist.Create;
+ dnsserverlag := tlist.Create;
end;
- {$ifdef win32}
- if iphlpapi=0 then iphlpapi := loadlibrary('iphlpapi.dll');
- if not assigned(getnetworkparams) then @getnetworkparams := getprocaddress(iphlpapi,'GetNetworkParams');
- if not assigned(getnetworkparams) then exit;
- fixed_info_len := 0;
- if GetNetworkParams(nil,@fixed_info_len)<>ERROR_BUFFER_OVERFLOW then exit;
- //fixed_info_len :=sizeof(tfixed_info);
- getmem(fixed_info,fixed_info_len);
- if GetNetworkParams(fixed_info,@fixed_info_len)<>0 then begin
- freemem(fixed_info);
- exit;
- end;
- currentdnsserver := @(fixed_info.dnsserverlist);
- while assigned(currentdnsserver) do begin
- dnsserverlist.Add(currentdnsserver.IpAddress);
- currentdnsserver := currentdnsserver.next;
- end;
- freemem(fixed_info);
- {$else}
- filemode := 0;
- assignfile(t,'/etc/resolv.conf');
- {$i-}reset(t);{$i+}
- if ioresult <> 0 then exit;
-
- while not eof(t) do begin
- readln(t,s);
- if not (copy(s,1,10) = 'nameserver') then continue;
- s := copy(s,11,500);
- while s <> '' do begin
- if (s[1] = #32) or (s[1] = #9) then s := copy(s,2,500) else break;
- end;
- a := pos(' ',s);
- if a <> 0 then s := copy(s,1,a-1);
- a := pos(#9,s);
- if a <> 0 then s := copy(s,1,a-1);
- //result := s;
- //if result <> '' then break;
- dnsserverlist.Add(s);
- end;
- close(t);
- {$endif}
+
+ dnsserverlist := getsystemdnsservers;
+ for a := biniplist_getcount(dnsserverlist)-1 downto 0 do dnsserverlag.Add(nil);
end;
procedure cleardnsservercache;
begin
- if assigned(dnsserverlist) then begin
- dnsserverlist.destroy;
- dnsserverlist := nil;
+ if assigned(dnsserverlag) then begin
+ dnsserverlag.destroy;
+ dnsserverlag := nil;
+ dnsserverlist := '';
end;
end;
-function getcurrentsystemnameserver(var id:integer):string;
+function getcurrentsystemnameserverbin(var id:integer):tbinip;
var
counter : integer;
-
begin
- if not assigned(dnsserverlist) then populatednsserverlist;
- if dnsserverlist.count=0 then raise exception.create('no dns servers availible');
- id := 0;
- if dnsserverlist.count >1 then begin
+ {override the name server choice here, instead of overriding it whereever it's called
+ setting ID to -1 causes it to be ignored in reportlag}
+ if (overridednsserver <> '') then begin
+ result := ipstrtobinf(overridednsserver);
+ if result.family <> 0 then begin
+ id := -1;
+ exit;
+ end;
+ end;
- for counter := 1 to dnsserverlist.count-1 do begin
- if taddrint(dnsserverlist.objects[counter]) < taddrint(dnsserverlist.objects[id]) then id := counter;
+ if not assigned(dnsserverlag) then populatednsserverlist;
+ if dnsserverlag.count=0 then raise exception.create('no dns servers availible');
+ id := 0;
+ if dnsserverlag.count >1 then begin
+ for counter := dnsserverlag.count-1 downto 1 do begin
+ if taddrint(dnsserverlag[counter]) < taddrint(dnsserverlag[id]) then id := counter;
end;
end;
- result := dnsserverlist[id]
+ result := biniplist_get(dnsserverlist,id);
+end;
+
+function getcurrentsystemnameserver(var id:integer):ansistring;
+begin
+ result := ipbintostr(getcurrentsystemnameserverbin(id));
end;
procedure reportlag(id:integer;lag:integer); //lag should be in microseconds and should be -1 to report a timeout
@@ -739,54 +670,19 @@ var
counter : integer;
temp : integer;
begin
- if (id < 0) or (id >= dnsserverlist.count) then exit;
+ if (id < 0) or (id >= dnsserverlag.count) then exit;
if lag = -1 then lag := timeoutlag;
- for counter := 0 to dnsserverlist.count-1 do begin
- temp := taddrint(dnsserverlist.objects[counter]) *15;
+ for counter := 0 to dnsserverlag.count-1 do begin
+ temp := taddrint(dnsserverlag[counter]) *15;
if counter=id then temp := temp + lag;
- dnsserverlist.objects[counter] := tobject(temp div 16);
+ dnsserverlag[counter] := tobject(temp div 16);
end;
end;
-
{$ifdef ipv6}
-{$ifdef linux}
-function getv6localips:tbiniplist;
-var
- t:textfile;
- s,s2:string;
- ip:tbinip;
- a:integer;
-begin
- result := biniplist_new;
-
- assignfile(t,'/proc/net/if_inet6');
- {$i-}reset(t);{$i+}
- if ioresult <> 0 then exit; {none found, return empty list}
-
- while not eof(t) do begin
- readln(t,s);
- s2 := '';
- for a := 0 to 7 do begin
- if (s2 <> '') then s2 := s2 + ':';
- s2 := s2 + copy(s,(a shl 2)+1,4);
- end;
- ipstrtobin(s2,ip);
- if ip.family <> 0 then biniplist_add(result,ip);
- end;
- closefile(t);
-end;
-
-{$else}
-function getv6localips:tbiniplist;
-begin
- result := biniplist_new;
-end;
-{$endif}
-
procedure initpreferredmode;
var
l:tbiniplist;