Implement discover

.vscode/launch.json

@@ -0,0 +1,27 @@
+{
+    // Use IntelliSense to learn about possible attributes.
+    // Hover to view descriptions of existing attributes.
+    // For more information, visit: https://go.microsoft.com/fwlink/?linkid=830387
+    "version": "0.2.0",
+    "configurations": [
+        {
+            "type": "lldb",
+            "request": "launch",
+            "name": "Debug unit tests in library 'midea'",
+            "cargo": {
+                "args": [
+                    "test",
+                    "--no-run",
+                    "--lib",
+                    "--package=midea"
+                ],
+                "filter": {
+                    "name": "midea",
+                    "kind": "lib"
+                }
+            },
+            "args": [],
+            "cwd": "${workspaceFolder}"
+        }
+    ]
+}

Cargo.toml

@@ -7,4 +7,6 @@ edition = "2021"
 
 [dependencies]
 anyhow = { version = "1.0.75", features = ["backtrace"] }
-if-addrs = "0.10.1"
+if-addrs = "0.10.1"
+aes = "0.8.3"
+rand = "0.8.5"

src/discover.rs

@@ -1,13 +1,66 @@
 use std::{
     collections::HashMap,
     net::{IpAddr, Ipv4Addr, SocketAddr, UdpSocket},
-    num::ParseIntError,
+    str::from_utf8,
     time::Duration,
 };
 
 use anyhow::Result;
 
-pub struct Startup {}
+use crate::{
+    hex,
+    security::{MsgType, Security},
+};
+
+#[derive(Debug, Clone)]
+pub struct DeviceInfo {
+    id: u64,
+    model: String,
+    sn: String,
+    protocol: u8,
+
+    addr: SocketAddr,
+}
+
+pub struct Device {
+    info: DeviceInfo,
+
+    socket: UdpSocket,
+}
+
+impl Device {
+    pub fn connect(info: DeviceInfo) -> Result<Self> {
+        let socket = UdpSocket::bind("0.0.0.0:0")?;
+        socket.set_write_timeout(Some(Duration::from_secs(10)))?;
+        socket.set_read_timeout(Some(Duration::from_secs(10)))?;
+
+        socket.connect(info.addr)?;
+
+        let me = Self { info, socket };
+
+        if me.info.protocol == 3 {
+            me.authenticate()?;
+        }
+
+        me.refresh_status()?;
+
+        Ok(me)
+    }
+
+    fn authenticate(&self) -> Result<()> {
+        let request = Security::encode_8370(MsgType::HANDSHAKE_REQUEST)?;
+
+        Ok(())
+    }
+
+    pub fn refresh_status(&self) -> Result<()> {
+        //
+
+        Ok(())
+    }
+}
+
+struct Startup;
 
 impl Startup {
     const BROADCAST_MSG: &'static [u8] = &[
@@ -18,16 +71,9 @@ impl Startup {
         0x42, 0xa5, 0x0f, 0x1f, 0x56, 0x9e, 0xb8, 0xec, 0x91, 0x8e, 0x92, 0xe5,
     ];
 
-    const DEVICE_INFO_MSG: &'static [u8] = &[
-        0x5a, 0x5a, 0x15, 0x00, 0x00, 0x38, 0x00, 0x04, 0x00, 0x00, 0x00, 0x00, 0x00, 0x27, 0x33,
-        0x05, 0x13, 0x06, 0x14, 0x14, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x03, 0xe8, 0x00, 0x00,
-        0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xca, 0x8d, 0x9b, 0xf9, 0xa0,
-        0x30, 0x1a, 0xe3, 0xb7, 0xe4, 0x2d, 0x53, 0x49, 0x47, 0x62, 0xbe,
-    ];
-
     const NUM_RETRIES: u8 = 5;
 
-    pub fn discover() -> Result<Self> {
+    pub fn discover() -> Result<Vec<DeviceInfo>> {
         let socket = UdpSocket::bind("0.0.0.0:0")?;
         socket.set_broadcast(true)?;
         socket.set_read_timeout(Some(Duration::from_secs(2)))?;
@@ -43,10 +89,10 @@ impl Startup {
                 if let Ok((bytes_read, addr)) = socket.recv_from(&mut buffer) {
                     let mut bytes = buffer[0..bytes_read].to_vec();
 
-                    let protocol = if bytes[..2] == Self::hex("5a5a")? {
+                    let protocol = if bytes[..2] == hex("5a5a")? {
                         2
-                    } else if bytes[..2] == Self::hex("8370")? {
-                        if bytes[8..10] == Self::hex("5a5a")? {
+                    } else if bytes[..2] == hex("8370")? {
+                        if bytes[8..10] == hex("5a5a")? {
                             bytes = bytes[8..(bytes.len() - 16)].to_vec();
                         }
 
@@ -61,16 +107,35 @@ impl Startup {
 
                     let device_id = u64::from_le_bytes(tmp.try_into().unwrap());
 
-                    if !devices.contains_key(&device_id) {
-                        devices.insert(device_id, (addr, bytes.to_vec(), protocol));
+                    if devices.contains_key(&device_id) {
+                        continue;
                     }
+
+                    let len = bytes.len();
+                    let encrypt_data = Security::decrypt(&mut bytes[40..(len - 16)]);
+
+                    let model = from_utf8(&encrypt_data[17..25])?;
+                    let sn = from_utf8(&encrypt_data[8..40])?;
+
+                    devices.insert(
+                        device_id,
+                        (addr, model.to_string(), sn.to_string(), protocol),
+                    );
                 }
             }
         }
 
-        println!("{devices:#?}");
+        Ok(devices
+            .into_iter()
+            .map(|(id, (addr, model, sn, protocol))| DeviceInfo {
+                id,
+                model,
+                sn,
+                protocol,
 
-        Ok(Self {})
+                addr,
+            })
+            .collect())
     }
 }
 
@@ -106,24 +171,28 @@ impl Startup {
 
         addresses
     }
-
-    fn hex(s: &str) -> Result<Vec<u8>, ParseIntError> {
-        (0..s.len())
-            .step_by(2)
-            .map(|i| u8::from_str_radix(&s[i..i + 2], 16))
-            .collect()
-    }
 }
 
 #[cfg(test)]
 mod test {
     use anyhow::Result;
 
-    use super::Startup;
+    use super::{Device, Startup};
 
     #[test]
     fn discover() -> Result<()> {
-        Startup::discover()?;
+        let devices = Startup::discover()?;
+
+        println!("{devices:#?}");
+
+        Ok(())
+    }
+
+    #[test]
+    fn connect() -> Result<()> {
+        for device_info in Startup::discover()? {
+            let device = Device::connect(device_info)?;
+        }
 
         Ok(())
     }

src/lib.rs

@@ -1 +1,11 @@
+use std::num::ParseIntError;
+
 mod discover;
+mod security;
+
+fn hex(s: &str) -> Result<Vec<u8>, ParseIntError> {
+    (0..s.len())
+        .step_by(2)
+        .map(|i| u8::from_str_radix(&s[i..i + 2], 16))
+        .collect()
+}

src/security.rs

@@ -0,0 +1,60 @@
+use aes::{
+    cipher::{generic_array::GenericArray, BlockDecrypt, KeyInit},
+    Aes128,
+};
+use anyhow::Result;
+use rand::{self, RngCore};
+
+use crate::hex;
+
+#[allow(non_camel_case_types)]
+#[repr(u8)]
+#[derive(Debug, PartialEq, Eq, PartialOrd, Ord)]
+pub enum MsgType {
+    HANDSHAKE_REQUEST = 0x0,
+    ANDSHAKE_RESPONSE = 0x1,
+    ENCRYPTED_RESPONSE = 0x3,
+    ENCRYPTED_REQUEST = 0x6,
+}
+
+pub struct Security;
+
+impl Security {
+    pub fn decrypt(data: &mut [u8]) -> &[u8] {
+        const N: u128 = 141661095494369103254425781617665632877;
+        const KEY: [u8; 16] = N.to_be_bytes();
+
+        let array = GenericArray::from(KEY);
+        let cipher = Aes128::new(&array);
+
+        for chunk in data.chunks_mut(16) {
+            let mut block = GenericArray::from_mut_slice(chunk);
+            cipher.decrypt_block(&mut block);
+        }
+
+        data
+    }
+
+    pub fn encode_8370(msg_type: MsgType) -> Result<String> {
+        let mut header = hex("83,70")?;
+        let mut data: Vec<u8> = Vec::new();
+
+        let mut size = data.len();
+        let mut padding = 0;
+
+        if msg_type == MsgType::ENCRYPTED_RESPONSE || msg_type == MsgType::ENCRYPTED_REQUEST {
+            if (size + 2) % 16 != 0 {
+                padding = 16 - ((size + 2) & 0xf);
+                size += padding + 32;
+                data.extend({
+                    let mut d = vec![0; padding];
+                    rand::thread_rng().fill_bytes(&mut d);
+
+                    d
+                });
+            }
+        }
+
+        todo!()
+    }
+}