[xiami] feat: implement xiami decipher

um_cli/Cargo.toml

@@ -11,5 +11,6 @@ umc_kgm = { path = "../um_crypto/kgm" }
 umc_kuwo = { path = "../um_crypto/kuwo" }
 umc_ncm = { path = "../um_crypto/ncm" }
 umc_qmc = { path = "../um_crypto/qmc" }
+umc_xiami = { path = "../um_crypto/xiami" }
 umc_xmly = { path = "../um_crypto/xmly" }
 umc_utils = { path = "../um_crypto/utils" }

um_cli/src/cmd/mod.rs

@@ -5,6 +5,7 @@ pub mod kgm;
 pub mod ncm;
 pub mod qmc1;
 pub mod qmc2;
+pub mod xiami;
 pub mod xmly;
 
 #[derive(Subcommand)]
@@ -21,4 +22,6 @@ pub enum Commands {
     JOOX(joox::ArgsJoox),
     #[command(name = "xmly")]
     XMLY(xmly::ArgsXimalaya),
+    #[command(name = "xiami")]
+    Xiami(xiami::ArgsXiami),
 }

um_cli/src/cmd/xiami.rs

@@ -0,0 +1,44 @@
+use crate::Cli;
+use anyhow::Result;
+use clap::Args;
+use std::fs::File;
+use std::io;
+use std::io::{BufReader, BufWriter, Read, Write};
+use std::path::PathBuf;
+
+/// Decrypt a XM file (Xiami)
+#[derive(Args)]
+pub struct ArgsXiami {
+    /// Path to output file, e.g. /export/Music/song.flac
+    #[clap(short, long)]
+    output: PathBuf,
+
+    /// Path to input file, e.g. /export/Music/song.xm
+    #[arg(name = "input")]
+    input: PathBuf,
+}
+
+impl ArgsXiami {
+    pub fn run(&self, cli: &Cli) -> Result<i32> {
+        let mut reader = BufReader::with_capacity(cli.buffer_size, File::open(&self.input)?);
+        let mut writer = BufWriter::with_capacity(cli.buffer_size, File::create(&self.output)?);
+
+        let mut header = [0u8; 0x10];
+        reader.read_exact(&mut header)?;
+        let xm = umc_xiami::XiamiFile::from_header(&header)?;
+        let mut copy_reader = (&mut reader).take(xm.copy_len as u64);
+        io::copy(&mut copy_reader, &mut writer)?;
+
+        let mut buffer = vec![0u8; cli.buffer_size];
+        loop {
+            let n = reader.read(&mut buffer[..])?;
+            if n == 0 {
+                break;
+            }
+            xm.decrypt(&mut buffer[..n]);
+            writer.write_all(&buffer[..n])?;
+        }
+
+        Ok(0)
+    }
+}

um_cli/src/main.rs

@@ -33,6 +33,7 @@ fn run_command(cli: &Cli) -> Result<i32> {
         Some(Commands::KGM(cmd)) => cmd.run(&cli),
         Some(Commands::JOOX(cmd)) => cmd.run(&cli),
         Some(Commands::XMLY(cmd)) => cmd.run(&cli),
+        Some(Commands::Xiami(cmd)) => cmd.run(&cli),
         None => {
             // https://github.com/clap-rs/clap/issues/3857#issuecomment-1161796261
             todo!("implement a sensible default command, similar to um/cli");