From 7e15ea607d60b4860d221161e128944b1017f1ee Mon Sep 17 00:00:00 2001
From: Maksim Syomochkin <maksim77ster@gmail.com>
Date: Thu, 10 Oct 2024 13:12:01 +0300
Subject: [PATCH] inital release

---
 .github/workflows/go.yaml |  33 +++++++++++++
 README.md                 |  14 ++++++
 go.mod                    |   3 ++
 go.sum                    |   0
 main.go                   | 101 ++++++++++++++++++++++++++++++++++++++
 5 files changed, 151 insertions(+)
 create mode 100644 .github/workflows/go.yaml
 create mode 100644 README.md
 create mode 100644 go.mod
 create mode 100644 go.sum
 create mode 100644 main.go

diff --git a/.github/workflows/go.yaml b/.github/workflows/go.yaml
new file mode 100644
index 0000000..a8d7981
--- /dev/null
+++ b/.github/workflows/go.yaml
@@ -0,0 +1,33 @@
+name: Go
+
+on:
+  create:
+    tags:
+      - v*
+
+jobs:
+
+  build:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v4
+
+    - name: Set up Go
+      uses: actions/setup-go@v4
+      with:
+        go-version: '1.23'
+
+    - name: Build
+      run: |
+        go build .
+        go get github.com/mitchellh/gox
+        /home/runner/go/bin/gox -osarch="linux/amd64 linux/arm darwin/amd64 windows/amd64" --output "build/{{ .Dir }}_{{.OS}}_{{.Arch}}"
+      
+    - name: Release
+      uses: softprops/action-gh-release@v2
+      with:
+        files: |
+            build/photok-recovery_darwin_amd64
+            build/photok-recovery_windows_amd64.exe
+            build/photok-recovery_linux_amd64
+            build/photok-recovery_linux_arm
\ No newline at end of file
diff --git a/README.md b/README.md
new file mode 100644
index 0000000..b41464c
--- /dev/null
+++ b/README.md
@@ -0,0 +1,14 @@
+# Photok Backup Recovery
+## Description
+
+This utility allows you to restore data from backups created by the Photok application without needing an Android phone. Easily access and recover your files directly from your computer.
+
+## Usage
+
+1. Go to the Releases page.
+2. Download the executable file for your platform.
+3. Run the utility using the command:
+```bash
+photok-recovery --password <your_password> --file <path_to_backup>
+```
+Replace <your_password> with your actual password and <path_to_backup> with the path to your backup file.
\ No newline at end of file
diff --git a/go.mod b/go.mod
new file mode 100644
index 0000000..1fcca31
--- /dev/null
+++ b/go.mod
@@ -0,0 +1,3 @@
+module github.com/maksim77/photok-recovery
+
+go 1.23.0
diff --git a/go.sum b/go.sum
new file mode 100644
index 0000000..e69de29
diff --git a/main.go b/main.go
new file mode 100644
index 0000000..9859282
--- /dev/null
+++ b/main.go
@@ -0,0 +1,101 @@
+package main
+
+import (
+	"archive/zip"
+	"crypto/aes"
+	"crypto/cipher"
+	"crypto/sha256"
+	"flag"
+	"io"
+	"log"
+	"os"
+	"strings"
+	"sync"
+)
+
+func main() {
+	password := flag.String("password", "", "photok password")
+	backupFile := flag.String("file", "", "path to backup file")
+	numWorkers := flag.Int("worker", 10, "number of workers")
+	flag.Parse()
+
+	var wg sync.WaitGroup
+
+	jobs := make(chan *zip.File)
+
+	for i := 0; i < *numWorkers; i++ {
+		wg.Add(1)
+
+		go worker(*password, jobs, &wg)
+	}
+
+	r, err := zip.OpenReader(*backupFile)
+	if err != nil {
+		log.Fatal(err)
+	}
+	defer r.Close()
+
+	for _, f := range r.File {
+		if !strings.HasSuffix(f.Name, ".tn") && strings.HasSuffix(f.Name, ".photok") {
+			jobs <- f
+		}
+	}
+
+	close(jobs)
+
+	wg.Wait()
+}
+
+func worker(password string, jobs <-chan *zip.File, wg *sync.WaitGroup) {
+	defer wg.Done()
+
+	key := photokKey(password)
+	iv := photokIV(password)
+
+	block, err := aes.NewCipher(key)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	aesgcm, err := cipher.NewGCMWithNonceSize(block, 16)
+	if err != nil {
+		log.Fatal(err)
+	}
+
+	for file := range jobs {
+		reader, err := file.Open()
+		if err != nil {
+			log.Fatal(err)
+		}
+
+		ciphertext, err := io.ReadAll(reader)
+		if err != nil {
+			log.Fatal(err)
+		}
+
+		plaintext, err := aesgcm.Open(nil, iv, ciphertext, nil)
+		if err != nil {
+			log.Fatal(err)
+		}
+
+		if err := os.WriteFile(file.Name+".plaintext", plaintext, 0o644); err != nil {
+			log.Fatal(err)
+		}
+	}
+}
+
+func photokKey(password string) []byte {
+	h := sha256.New()
+	h.Write([]byte(password))
+
+	return h.Sum(nil)
+}
+
+func photokIV(password string) []byte {
+	iv := make([]byte, 16)
+	for i := 0; i < 16 && i < len(password); i++ {
+		iv[i] = password[i]
+	}
+
+	return iv
+}