// status codes passed up on status indications.
IP_ADDR_DELETED = (IP_STATUS_BASE + 19);
IP_SPEC_MTU_CHANGE = (IP_STATUS_BASE + 20);
IP_MTU_CHANGE = (IP_STATUS_BASE + 21);
IP_GENERAL_FAILURE = (IP_STATUS_BASE + 50);
MAX_IP_STATUS = IP_GENERAL_FAILURE;
IP_PENDING = (IP_STATUS_BASE + 255);
// IP header flags
IP_FLAG_DF = $02; // Don't fragment this packet.
// IP Option Types
IP_OPT_EOL = $00; // End of list option
IP_OPT_NOP = $01; // No operation
IP_OPT_SECURITY = $82; // Security option.
IP_OPT_LSRR = $83; // Loose source route.
IP_OPT_SSRR = $89; // Strict source route.
IP_OPT_RR = $07; // Record route.
IP_OPT_TS = $44; // Timestamp.
IP_OPT_SID = $88; // Stream ID (obsolete)
MAX_OPT_SIZE = $40;
type
// IP types
TIPAddr = LongInt; // An IP address.
TIPMask = LongInt; // An IP subnet mask.
TIPStatus = LongInt; // Status code returned from IP APIs.
PIPOptionInformation = ^TIPOptionInformation;
TIPOptionInformation = packed record
TTL: Byte; // Time To Live (used for traceroute)
TOS: Byte; // Type Of Service (usually 0)
Flags: Byte; // IP header flags (usually 0)
OptionsSize: Byte; // Size of options data (usually 0, max 40)
OptionsData: PChar; // Options data buffer
end;
PIcmpEchoReply = ^TIcmpEchoReply;
TIcmpEchoReply = packed record
Address: TIPAddr; // Replying address
Status: DWord; // IP status value
RTT: DWord; // Round Trip Time in milliseconds
DataSize: Word; // Reply data size
Reserved: Word; // Reserved
Data: Pointer; // Pointer to reply data buffer
Options: TIPOptionInformation; // Reply options
end;
// IcmpCreateFile:
// Opens a handle on which ICMP Echo Requests can be issued.
// Arguments:
// None.
// Return Value:
// An open file handle or INVALID_HANDLE_VALUE. Extended error information
// is available by calling GetLastError().
TIcmpCreateFile = function: THandle; stdcall;
// IcmpCloseHandle:
// Closes a handle opened by ICMPOpenFile.
// Arguments:
// IcmpHandle - The handle to close.
// Return Value:
// TRUE if the handle was closed successfully, otherwise FALSE. Extended
// error information is available by calling GetLastError().
TIcmpCloseHandle = function(IcmpHandle: THandle): Boolean; stdcall;
// IcmpSendEcho:
// Sends an ICMP Echo request and returns one or more replies. The
// call returns when the timeout has expired or the reply buffer
// is filled.
// Arguments:
// IcmpHandle - An open handle returned by ICMPCreateFile.
// DestinationAddress - The destination of the echo request.
// RequestData - A buffer containing the data to send in the
// request.
// RequestSize - The number of bytes in the request data buffer.
// RequestOptions - Pointer to the IP header options for the request.
// May be NULL.
// ReplyBuffer - A buffer to hold any replies to the request.
// On return, the buffer will contain an array of
// ICMP_ECHO_REPLY structures followed by options
// and data. The buffer should be large enough to
// hold at least one ICMP_ECHO_REPLY structure
// and 8 bytes of data - this is the size of
// an ICMP error message.
// ReplySize - The size in bytes of the reply buffer.
// Timeout - The time in milliseconds to wait for replies.
// Return Value:
// Returns the number of replies received and stored in ReplyBuffer. If
// the return value is zero, extended error information is available
// via GetLastError().
TIcmpSendEcho = function(IcmpHandle: THandle;
DestinationAddress: TIPAddr;
RequestData: Pointer;
RequestSize: Word;
RequestOptions: PIPOptionInformation;
ReplyBuffer: Pointer;
ReplySize: DWord;
Timeout: DWord
): DWord; stdcall;
// Event handler type declaration for TICMP.OnDisplay event.
TICMPDisplay = procedure(Sender: TObject; Msg : String) of object;
TICMPReply = procedure(Sender: TObject; Error : Integer) of object;
// The object wich encapsulate the ICMP.DLL
TICMP = class(TObject)
private
hICMPdll : HModule; // Handle for ICMP.DLL
IcmpCreateFile : TIcmpCreateFile;
IcmpCloseHandle : TIcmpCloseHandle;
IcmpSendEcho : TIcmpSendEcho;
hICMP : THandle; // Handle for the ICMP Calls
FReply : TIcmpEchoReply; // ICMP Echo reply buffer
FAddress : String; // Address given
FHostName : String; // Dotted IP of host (output)
FHostIP : String; // Name of host (Output)
FIPAddress : TIPAddr; // Address of host to contact
FSize : Integer; // Packet size (default to 56)
FTimeOut : Integer; // Timeout (default to 4000mS)
FTTL : Integer; // Time To Live (for send)
FFlags : Integer; // Options flags
FOnDisplay : TICMPDisplay; // Event handler to display
FOnEchoRequest : TNotifyEvent;
FOnEchoReply : TICMPReply;
FLastError : DWORD; // After sending ICMP packet
FAddrResolved : Boolean;
procedure ResolveAddr;
public
constructor Create; virtual;
destructor Destroy; override;
function Ping : Integer;
procedure SetAddress(Value : String);
function GetErrorString : String;
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *}
function MinInteger(X, Y: Integer): Integer;
begin
if X >= Y then
Result := Y
else
Result := X;
end;
{* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * *}
procedure TICMP.ResolveAddr;
var
Phe : PHostEnt; // HostEntry buffer for name lookup
begin
// Convert host address to IP address
FIPAddress := inet_addr(PChar(FAddress));
if FIPAddress <> LongInt(INADDR_NONE) then
// Was a numeric dotted address let it in this format
FHostName := FAddress
else begin
// Not a numeric dotted address, try to resolve by name
Phe := GetHostByName(PChar(FAddress));
if Phe = nil then begin
FLastError := GetLastError;
if Assigned(FOnDisplay) then
FOnDisplay(Self, 'Unable to resolve ' + FAddress);
Exit;
end;
if FIPAddress = LongInt(INADDR_NONE) then begin
FLastError := IP_BAD_DESTINATION;
if Assigned(FOnDisplay) then
FOnDisplay(Self, 'Invalid host address');
Exit;
end;
// Allocate space for data buffer space
BufferSize := SizeOf(TICMPEchoReply) + FSize;
GetMem(pReqData, FSize);
GetMem(pData, FSize);
GetMem(pIPE, BufferSize);
try
// Fill data buffer with some data bytes
FillChar(pReqData^, FSize, $20);
Msg := 'Pinging from Delphi code written by F. Piette';
Move(Msg[1], pReqData^, MinInteger(FSize, Length(Msg)));
procedure Register;
begin
RegisterComponents('COOL', [TPing]);
end;
function XSocketWindowProc(
ahWnd : HWND;
auMsg : Integer;
awParam : WPARAM;
alParam : LPARAM): Integer; stdcall;
var
Obj : TPing;
MsgRec : TMessage;
begin
Obj := TPing(GetWindowLong(ahWnd, 0));
if not Assigned(Obj) then
Result := DefWindowProc(ahWnd, auMsg, awParam, alParam)
else begin
MsgRec.Msg := auMsg;
MsgRec.wParam := awParam;
MsgRec.lParam := alParam;
Obj.WndProc(MsgRec);
Result := MsgRec.Result;
end;
end;
var
XSocketWindowClass: TWndClass = (
style : 0;
lpfnWndProc : @XSocketWindowProc;
cbClsExtra : 0;
cbWndExtra : SizeOf(Pointer);
hInstance : 0;
hIcon : 0;
hCursor : 0;
hbrBackground : 0;
lpszMenuName : nil;
lpszClassName : 'ICSPingWindowClass');
function XSocketAllocateHWnd(Obj : TObject): HWND;
var
TempClass : TWndClass;
ClassRegistered : Boolean;
begin
{ Check if the window class is already registered }
XSocketWindowClass.hInstance := HInstance;
ClassRegistered := GetClassInfo(HInstance,
XSocketWindowClass.lpszClassName,
TempClass);
if not ClassRegistered then begin
Result := Windows.RegisterClass(XSocketWindowClass);
if Result = 0 then
Exit;
end;
if (Result <> 0) and Assigned(Obj) then
SetWindowLong(Result, 0, Integer(Obj));
end;
procedure XSocketDeallocateHWnd(Wnd: HWND);
begin
DestroyWindow(Wnd);
end;
procedure TPing.WndProc(var MsgRec: TMessage);
begin
with MsgRec do begin
if Msg = WM_ASYNCGETHOSTBYNAME then
WMAsyncGetHostByName(MsgRec)
else
Result := DefWindowProc(Handle, Msg, wParam, lParam);
end;
end;
procedure TPing.WMAsyncGetHostByName(var msg: TMessage);
var
Phe : Phostent;
IPAddr : TInAddr;
Error : Word;
begin
if msg.wParam <> LongInt(FDnsLookupHandle) then
Exit;
FDnsLookupHandle := 0;
Error := Msg.LParamHi;
if Error = 0 then begin
Phe := PHostent(@FDnsLookupBuffer);
IPAddr := PInAddr(Phe^.h_addr_list^)^;
FDnsResult := StrPas(inet_ntoa(IPAddr));
end;
if Assigned(FOnDnsLookupDone) then
FOnDnsLookupDone(Self, Error);
end;
constructor TPing.Create(Owner : TComponent);
begin
Inherited Create(Owner);
FIcmp := TICMP.Create;
FIcmp.OnDisplay := IcmpDisplay;
FIcmp.OnEchoRequest := IcmpEchoRequest;
FIcmp.OnEchoReply := IcmpEchoReply;
{ Delphi 32 bits has threads and VCL is not thread safe. }
{ We need to do our own way to be thread safe. }
FWindowHandle := XSocketAllocateHWnd(Self);
end;
destructor TPing.Destroy;
begin
CancelDnsLookup; { Cancel any pending dns lookup }
XSocketDeallocateHWnd(FWindowHandle);
if Assigned(FIcmp) then begin
FIcmp.Destroy;
FIcmp := nil;
end;
inherited Destroy;
end;
procedure TPing.IcmpDisplay(Sender: TObject; Msg: String);
begin
if Assigned(FOnDisplay) then
FOnDisplay(Self, Sender, Msg);
end;
procedure TPing.IcmpEchoReply(Sender: TObject; Error : Integer);
begin
if Assigned(FOnEchoReply) then
FOnEchoReply(Self, Sender, Error);
end;
procedure TPing.IcmpEchoRequest(Sender: TObject);
begin
if Assigned(FOnEchoRequest) then
FOnEchoRequest(Self, Sender);
end;
function TPing.Ping : Integer;
begin
if Assigned(FIcmp) then
Result := FIcmp.Ping
else
Result := 0;
end;
procedure TPing.CancelDnsLookup;
begin
if FDnsLookupHandle = 0 then
Exit;
if WSACancelAsyncRequest(FDnsLookupHandle) <> 0 then
raise Exception.CreateFmt('WSACancelAsyncRequest failed, error #%d',
[WSAGetLastError]);
FDnsLookupHandle := 0;
if Assigned(FOnDnsLookupDone) then
FOnDnsLookupDone(Self, WSAEINTR);
end;
procedure TPing.DnsLookup(HostName : String);
var
IPAddr : TInAddr;
begin
if FDnsLookupHandle <> 0 then
WSACancelAsyncRequest(FDnsLookupHandle);
FDnsResult := '';
IPAddr.S_addr := Inet_addr(@HostName[1]);
if IPAddr.S_addr <> u_long(INADDR_NONE) then begin
FDnsResult := StrPas(inet_ntoa(IPAddr));
if Assigned(FOnDnsLookupDone) then
FOnDnsLookupDone(Self, 0);
Exit;
end;
FDnsLookupHandle := WSAAsyncGetHostByName(FWindowHandle,
WM_ASYNCGETHOSTBYNAME,
@HostName[1],
@FDnsLookupBuffer,
SizeOf(FDnsLookupBuffer));
if FDnsLookupHandle = 0 then
raise Exception.CreateFmt(
'%s: can''t start DNS lookup, error #%d',
[HostName, WSAGetLastError]);
end;
procedure TPing.SetAddress(Value : String);
begin
if Assigned(FIcmp) then
FIcmp.Address := Value;
end;
function TPing.GetAddress : String;
begin
if Assigned(FIcmp) then
Result := FIcmp.Address
else
Result := '';
end;
procedure TPing.SetSize(Value : Integer);
begin
if Assigned(FIcmp) then
FIcmp.Size := Value;
end;
function TPing.GetSize : Integer;
begin
if Assigned(FIcmp) then
Result := FIcmp.Size
else
Result := 0;
end;
procedure TPing.SetTimeout(Value : Integer);
begin
if Assigned(FIcmp) then
FIcmp.Timeout := Value;
end;
function TPing.GetTimeout : Integer;
begin
if Assigned(FIcmp) then
Result := FIcmp.Timeout
else
Result := 0;
end;
procedure TPing.SetTTL(Value : Integer);
begin
if Assigned(FIcmp) then
FIcmp.TTL := Value;
end;
function TPing.GetTTL : Integer;
begin
if Assigned(FIcmp) then
Result := FIcmp.TTL
else
Result := 0;
end;
procedure TPing.SetFlags(Value : Integer);
begin
if Assigned(FIcmp) then
FIcmp.Flags := Value;
end;
function TPing.GetFlags : Integer;
begin
if Assigned(FIcmp) then
Result := FIcmp.flags
else
Result := 0;
end;
function TPing.GetReply : TIcmpEchoReply;
begin
if Assigned(FIcmp) then
Result := FIcmp.Reply
else
FillChar(Result, SizeOf(Result), 0);
end;
function TPing.GetErrorCode : Integer;
begin
if Assigned(FIcmp) then
Result := FIcmp.ErrorCode
else
Result := -1;
end;
function TPing.GetErrorString : String;
begin
if Assigned(FIcmp) then
Result := FIcmp.ErrorString
else
Result := '';
end;