Implement ReadProcessMemory compression

Cargo.lock

@@ -1,5 +1,11 @@
 # This file is automatically @generated by Cargo.
 # It is not intended for manual editing.
+[[package]]
+name = "adler"
+version = "0.2.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ee2a4ec343196209d6594e19543ae87a39f96d5534d7174822a3ad825dd6ed7e"
+
 [[package]]
 name = "arrayref"
 version = "0.3.6"
@@ -47,6 +53,7 @@ version = "0.1.0"
 dependencies = [
  "bytes",
  "log",
+ "miniz_oxide",
  "simplelog",
  "tokio",
  "winapi",
@@ -156,6 +163,16 @@ version = "2.3.4"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0ee1c47aaa256ecabcaea351eae4a9b01ef39ed810004e298d2511ed284b1525"
 
+[[package]]
+name = "miniz_oxide"
+version = "0.4.3"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0f2d26ec3309788e423cfbf68ad1800f061638098d76a83681af979dc4eda19d"
+dependencies = [
+ "adler",
+ "autocfg",
+]
+
 [[package]]
 name = "mio"
 version = "0.7.5"

Cargo.toml

@@ -9,6 +9,7 @@ edition = "2018"
 [dependencies]
 bytes = "0.6"
 log = "0.4.11"
+miniz_oxide = "0.4.3"
 simplelog = "0.7.6"
 tokio = { version = "0.3.3", features = ["net", "rt-multi-thread", "io-util"] }
 winapi = { version = "0.3.9", features = ["memoryapi", "processthreadsapi", "tlhelp32", "winnt"], optional = true }

src/server/ce_common.rs

@@ -105,3 +105,24 @@ pub fn get_process_architecture() -> Architecture {
         std::compile_error!("Current architecture is not supported by Cheat Engine")
     }
 }
+
+#[derive(Debug)]
+pub enum ReadMemoryData {
+    Uncompressed {
+        data: Vec<u8>,
+    },
+    Compressed {
+        uncompressed_size: u32,
+        compressed_data: Vec<u8>,
+    },
+}
+
+pub fn compress_data(data: Vec<u8>, level: u8) -> Vec<u8> {
+    // const BLOCK_SIZE: usize = 64 * 1024;
+    // let max_blocks = 1 + (data.len() / BLOCK_SIZE);
+    // let blocks = vec![[0u8; BLOCK_SIZE]; max_blocks];
+
+    // deflate to first block
+    let compressed = miniz_oxide::deflate::compress_to_vec_zlib(&data[..], level);
+    compressed
+}

src/server/commands_request.rs

@@ -167,7 +167,7 @@ pub struct ReadProcessMemoryRequest {
     pub handle: u32,
     pub address: u64,
     pub size: u32,
-    pub compress: bool,
+    pub compression_level: u8,
 }
 
 impl CERequest for ReadProcessMemoryRequest {
@@ -180,7 +180,7 @@ impl CERequest for ReadProcessMemoryRequest {
             handle: buf.get_u32_le(),
             address: buf.get_u64_le(),
             size: buf.get_u32_le(),
-            compress: buf.get_u8() != 0,
+            compression_level: buf.get_u8(),
         }
     }
 }

src/server/commands_response.rs

@@ -91,13 +91,25 @@ impl CEResponse for GetSymbolListFromFileResponse {
 
 #[derive(Debug)]
 pub struct ReadProcessMemoryResponse {
-    pub data: Vec<u8>,
+    pub data: ReadMemoryData,
 }
 
 impl CEResponse for ReadProcessMemoryResponse {
     fn serialize(self, writer: &mut dyn BufMut) {
-        writer.put_i32_le(self.data.len() as i32);
-        writer.put_slice(&self.data[..]);
+        match self.data {
+            ReadMemoryData::Uncompressed { data } => {
+                writer.put_i32_le(data.len() as i32);
+                writer.put_slice(&data[..]);
+            }
+            ReadMemoryData::Compressed {
+                uncompressed_size,
+                compressed_data,
+            } => {
+                writer.put_u32_le(uncompressed_size);
+                writer.put_u32_le(compressed_data.len() as u32);
+                writer.put_slice(&compressed_data[..]);
+            }
+        }
     }
 }
 

src/server/handlers/windows.rs

@@ -157,10 +157,18 @@ impl Handler<ReadProcessMemoryRequest> for WindowsHandler {
                 &mut bytes_read,
             )
         };
-        if req.compress {
-            todo!()
+        if req.compression_level != 0 {
+            buffer = compress_data(buffer, req.compression_level);
+            ReadProcessMemoryResponse {
+                data: ReadMemoryData::Compressed {
+                    uncompressed_size: bytes_read as u32,
+                    compressed_data: buffer,
+                },
+            }
         } else {
-            ReadProcessMemoryResponse { data: buffer }
+            ReadProcessMemoryResponse {
+                data: ReadMemoryData::Uncompressed { data: buffer },
+            }
         }
     }
 }