How to get all the exported functions in a DLL? - delphi

Question

How can I get all the exported functions from a DLL, programmatically? I am trying to compare two DLL's for exported functions.

Answer 1

This is the code that I use:
uses
System.Classes, Winapi.Windows;
type
PIMAGE_NT_HEADERS = ^IMAGE_NT_HEADERS;
PIMAGE_EXPORT_DIRECTORY = ^IMAGE_EXPORT_DIRECTORY;
function ImageNtHeader(Base: Pointer): PIMAGE_NT_HEADERS; stdcall; external 'dbghelp.dll';
function ImageRvaToVa(NtHeaders: Pointer; Base: Pointer; Rva: ULONG; LastRvaSection: Pointer): Pointer; stdcall; external 'dbghelp.dll';
procedure EnumerateImageExportedFunctionNames(const ImageName: string; NamesList: TStrings);
var
i: Integer;
FileHandle: THandle;
ImageHandle: THandle;
ImagePointer: Pointer;
Header: PIMAGE_NT_HEADERS;
ExportTable: PIMAGE_EXPORT_DIRECTORY;
NamesPointer: Pointer;
NamesPtr: PCardinal;
NamePtr: PAnsiChar;
begin
//NOTE: our policy in this procedure is to exit upon any failure and return and empty list
NamesList.Clear;
FileHandle := CreateFile(
PChar(ImageName),
GENERIC_READ,
FILE_SHARE_READ,
nil,
OPEN_EXISTING,
FILE_ATTRIBUTE_NORMAL,
0
);
if FileHandle=INVALID_HANDLE_VALUE then begin
exit;
end;
Try
ImageHandle := CreateFileMapping(FileHandle, nil, PAGE_READONLY, 0, 0, nil);
if ImageHandle=0 then begin
exit;
end;
Try
ImagePointer := MapViewOfFile(ImageHandle, FILE_MAP_READ, 0, 0, 0);
if not Assigned(ImagePointer) then begin
exit;
end;
Try
Header := ImageNtHeader(ImagePointer);
if not Assigned(Header) then begin
exit;
end;
if Header.Signature<>$00004550 then begin // "PE\0\0" as a DWORD.
exit;
end;
ExportTable := ImageRvaToVa(Header, ImagePointer, Header.OptionalHeader.DataDirectory[0].VirtualAddress, nil);
if not Assigned(ExportTable) then begin
exit;
end;
NamesPtr := ImageRvaToVa(Header, ImagePointer, Cardinal(ExportTable.AddressOfNames), nil);
if not Assigned(NamesPtr) then begin
exit;
end;
for i := 0 to ExportTable.NumberOfNames-1 do begin
NamePtr := ImageRvaToVa(Header, ImagePointer, NamesPtr^, nil);
if not Assigned(NamePtr) then begin
exit;
end;
NamesList.Add(NamePtr);
inc(NamesPtr);
end;
Finally
UnmapViewOfFile(ImagePointer); // Ignore error as there is not much we could do.
End;
Finally
CloseHandle(ImageHandle);
End;
Finally
CloseHandle(FileHandle);
End;
end;

Answer 2

I came here to find a way to list all functions contained within an ocx (which is basically a dll). All infos here didn't give me what I was looking for. But then I found the free dllexp.exe from nirsoft (https://www.nirsoft.net/utils/dll_export_viewer.html).
Direct download link: https://www.nirsoft.net/packages/progtools.zip which perfectly shows all exported functions of a dll/ocx and is very user-friendly.