Command-line support?

[Baltazar500]

Hi.

Can you add support for a command-line without GUI and output to the console?

[stunndard]

No problem implementing it, but there's a couple of thoughts. Usually, a command line is useful when integrating with a build process, i.e. when you build a Go executable. But the patch is a 2-step process: besides patching the EXE file, it's also necessary to drop DLL files into the system directory on the target Win7 system, otherwise the patched EXE will not work anywhere. So the patcher is useless at build time and reasonable only on a target Win 7 system.

And, on the target system it's aimed at end-users who would conveniently patch a stock-built Go EXE on their system using a GUI and make it work.

So what is your use case and why do you need a command line?

[Baltazar500]

I use a lot of go console and other console utilities. I work mostly on the command line and for me there is no need for a GUI :) Additionally, the console version can be used through the right-click context menu through the registry, etc.

[sot-tech]

@Baltazar500 If relevant, you can use something like this as sample code (Golang), but you still need to place DLL by yourself:

// Package main contains patcher for windows executable to use Go-compiled .exe file in version 7 (2008 R2)
// It just replaces bcryptprimitives.dll call with acryptprimitives.dll.
// acryptprimitives.dll *MUST* present in C:\windows\system32 directory before app start.
// Original patcher: https://github.com/stunndard/golangwin7patch
package main

import (
	"bytes"
	_ "embed"
	"errors"
	"flag"
	"fmt"
	"log"
	"os"
	"path/filepath"

	"golang.org/x/text/encoding/unicode"
)

var (
	oldDLL = []byte("bcryptprimitives.dll")
	newDLL = []byte("acryptprimitives.dll")
)

//go:embed "acryptprimitives.dll"
var dllData []byte

func main() {
	flag.Parse()
	args := flag.Args()
	if len(args) == 0 {
		log.Fatalln("input file not provided")
	}
	data, err := os.ReadFile(args[0])
	if err != nil {
		log.Fatalln(err)
	}
	if len(data) < 0x90 ||
		data[0] != 0x4D || data[1] != 0x5A || // exe magic
		data[0x80] != 0x50 || data[0x81] != 0x45 || // PE format
		data[0x84] != 0x64 || data[0x85] != 0x86 { // x86-64
		fmt.Printf("0x80 - 0x%X, but 0x50 required\n", data[0x80])
		fmt.Printf("0x81 - 0x%X, but 0x45 required\n", data[0x81])
		fmt.Printf("0x84 - 0x%X, but 0x64 required\n", data[0x84])
		fmt.Printf("0x85 - 0x%X, but 0x86 required\n", data[0x85])
		log.Fatalln("file not seems to be windows x64 executable")
	}
	newData := bytes.ReplaceAll(data, oldDLL, newDLL)
	u16 := unicode.UTF16(unicode.LittleEndian, unicode.IgnoreBOM).NewEncoder()
	oldDLLu16, _ := u16.Bytes(oldDLL)
	newDLLu16, _ := u16.Bytes(newDLL)
	newData = bytes.ReplaceAll(newData, oldDLLu16[:len(oldDLLu16)-1], newDLLu16[:len(newDLLu16)-1])

	if bytes.Equal(data, newData) {
		log.Print("file already patched")
	} else {
		if err = os.Rename(args[0], args[0]+".bak"); err != nil {
			log.Fatalln(err)
		}
		if err = os.WriteFile(args[0], newData, 0o600); err != nil {
			log.Fatalln(err)
		}
		log.Println("file patched")
	}

	dllPath := filepath.Join(filepath.Dir(args[0]), string(newDLL))
	_, err = os.Stat(dllPath)
	if err == nil {
		log.Println("DLL already exists")
	} else if errors.Is(err, os.ErrNotExist) {
		err = os.WriteFile(dllPath, dllData, 0o600)
		if err != nil {
			log.Fatalln(err)
		}
		log.Println(`DLL placed to the same directory as provided file. don't forget to place it into C:\windows\system32 directory`)
	} else if err != nil {
		log.Fatalln(err)
	}
}

It also needs DLL in the same directory with .go file at compile time.

[Baltazar500]

@sot-tech , sorry, I'm not writing on go. Can you compile this code ? Is this command-line version of the patch ?

[sot-tech]

@sot-tech , sorry, I'm not writing on go. Can you compile this code ? Is this command-line version of the patch ?

Yes, this is CLI, first argument is file to be patched.

Compiled code (linux x64 and windows 12r2+ x64): winpatcher.tar.gz

[Baltazar500]

@sot-tech , Thank you, I checked

Under Windows 7 did not start ...

C:\Users\Admin>c:\Software\test\winpatch_windows_x86-64.exe --help
Exception 0xc0000005 0x8 0x0 0x0
PC=0x0

runtime.asmstdcall(0x0)
        runtime/sys_windows_amd64.s:76 +0x89 fp=0x27f9b0 sp=0x27f990 pc=0x12890e9
rax     0x0
rbx     0x13ea0d8
rcx     0x14305a8
rdx     0x20
rdi     0x7fffffdd000
rsi     0x27fbb0
rbp     0x27faf0
rsp     0x27f988
r8      0x13e9de0
r9      0x143042b
r10     0x0
r11     0x246
r12     0x27fbf0
r13     0xffffffffffffffff
r14     0x13e9140
r15     0x2031
rip     0x0
rflags  0x10246
cs      0x33
fs      0x53
gs      0x2b

Ironically, cmd - patcher had to be fix using GUI patcher :)

checking file: winpatch_windows_x86-64.exe...
patching at: 0x00128D5D
patching at: 0x0012BF9B
patching at: 0x001CB980
patching at: 0x001CBC00
saved ok.
backup saved ok.
file successfully patched.

checking additional files...
C:\Windows\System32\acryptprimitives.dll is correct version, no change required.
C:\Windows\Sysnative\acryptprimitives.dll is correct version, no change required.
additional files are ok.

After that, patcher began to work, but refused to make corrections to the X86 binary

C:\Users\Admin>c:\Software\test\winpatch_windows_x86-64.exe C:\Software\test\psiphon-tunnel-core-i686.exe
0x80 - 0x50, but 0x50 required
0x81 - 0x45, but 0x45 required
0x84 - 0x4C, but 0x64 required
0x85 - 0x1, but 0x86 required
2025/07/23 12:11:35 file not seems to be windows x64 executable

GUI patcher made corrections to the X86 binary without problems

checking file: psiphon-tunnel-core-i686.exe...
patching at: 0x00E300BD
patching at: 0x00E431DE
patching at: 0x0178AB80
saved ok.
backup saved ok.
file successfully patched.

checking additional files...
C:\Windows\System32\acryptprimitives.dll is correct version, no change required.
C:\Windows\Sysnative\acryptprimitives.dll is correct version, no change required.
additional files are ok.

[sot-tech]

@Baltazar500 sorry for long answer, notification seems not working (again).
Previously executable only for x64 and not self-patched.
For both x32 and x64 try this: https://github.com/sot-tech/gw7p/ .

[Baltazar500]

@sot-tech, thanks for the feedback, I checked the new cmd fixer - everything is ok with patching x86 and x64 exe files. There are a few comments that I will write in issue