feat: add decrypt-rs

decrypt-rs/src/main.rs

@@ -0,0 +1,78 @@
+#!/usr/bin/env runrs
+
+//! ```cargo
+//! [dependencies]
+//! aes-gcm = { version = "0.10.1", features = ["zeroize", "stream"] }
+//! hex = "0.4.3"
+//! rust_util = "0.6.41"
+//! ```
+
+use std::fs;
+use aes_gcm::aead::Aead;
+use aes_gcm::{Aes256Gcm, Key, KeyInit};
+
+use rust_util::{failure_and_exit, information, opt_result, success, warning, XResult};
+
+// see https://git.hatter.ink/hatter/crypto/src/branch/master/src/main/java/me/hatter/tools/crypto/stream/DecryptTool.java
+fn main() -> XResult<()> {
+    let args: Vec<String> = std::env::args().skip(1).collect();
+    if args.len() != 3 {
+        failure_and_exit!("crypt.rs <key-hex> <file-in> <file-out>");
+    }
+    let key_bytes = opt_result!(hex::decode(&args[0]), "Decode key failed: {}");
+    if key_bytes.len() != 32 {
+        failure_and_exit!("Key length must be 32 bytes, but is: {}", key_bytes.len());
+    }
+
+    let file_in = &args[1];
+    let file_out = &args[2];
+    let file_in_meta = fs::metadata(file_in);
+
+    match file_in_meta {
+        Err(_) => failure_and_exit!("File in not exists: {}", file_in),
+        Ok(file_in_meta) => {
+            let file_in_len = file_in_meta.len();
+            if file_in_len < 100 * 1024 * 1024 {
+                success!("File in: {}, size: {}", file_in, file_in_len);
+            } else {
+                warning!("File in: {}, size: {}", file_in, file_in_len);
+            }
+        }
+    }
+    if is_file_exists(file_out) {
+        failure_and_exit!("File out exists: {}", file_out);
+    }
+
+    information!("Reading file in: {}", file_in);
+    let file_in_bytes = opt_result!(fs::read(&file_in), "Open file: {}, failed: {}", file_in);
+    let magic = &file_in_bytes[0..4];
+    let digest = &file_in_bytes[4..4 + 32];
+    information!("Magic: {}", hex::encode(magic));
+    information!("Key digest: {}", hex::encode(digest));
+
+    if hex::encode(magic) != "e2c50001" {
+        failure_and_exit!("Magic number error: {}", hex::encode(magic));
+    }
+
+    let mut nonce_bytes = [0_u8; 12];
+    for i in 0..12 {
+        nonce_bytes[i] = file_in_bytes[4 + 32 + i];
+    }
+    let file_in_bytes_content = &file_in_bytes[48..];
+
+    let key = Key::<Aes256Gcm>::from_slice(&key_bytes);
+    let nonce = nonce_bytes.into();
+
+    let aes256_gcm = Aes256Gcm::new(&key);
+    let decrypted = opt_result!(aes256_gcm.decrypt(&nonce, file_in_bytes_content), "Decrypt failed: {}");
+
+    information!("Writing file out: {}", file_out);
+    opt_result!(fs::write(&file_out, decrypted), "Write file out: {}, failed: {}", file_out);
+
+    success!("Write file out succeed!");
+    Ok(())
+}
+
+fn is_file_exists(file: &str) -> bool {
+    fs::metadata(file).is_ok()
+}