refactor(mstsgu): follow up to PR 913 (#920)

- Update tokio-tungstenite to latest
- Fix the dependencies
- Move the top-level documentation into a README.md that we re-include
in the source code
- Re-order the imports using the nightly formater
- Audit the unwraps and remove them
- Fix the UTF-16 string length computation

ARCHITECTURE.md

@@ -256,6 +256,10 @@ State machines to drive an RDP connection acceptance sequence
 
 Extendable skeleton for implementing custom RDP servers.
 
+#### [`crates/ironrdp-mstsgu`](./crates/ironrdp-mstsgu) (@steffengy)
+
+Terminal Services Gateway Server Protocol implementation.
+
 #### [`crates/ironrdp-glutin-renderer`](./crates/ironrdp-glutin-renderer) (no maintainer)
 
 `glutin` primitives for OpenGL rendering.

Cargo.lock

@@ -1510,7 +1510,7 @@ dependencies = [
  "embed-resource",
  "ironrdp",
  "ironrdp-cliprdr-native",
- "ironrdp-core 0.1.5",
+ "ironrdp-core",
  "sspi",
  "thiserror 2.0.14",
  "tracing",
@@ -2332,7 +2332,7 @@ dependencies = [
  "ironrdp-cliprdr",
  "ironrdp-cliprdr-native",
  "ironrdp-connector",
- "ironrdp-core 0.1.5",
+ "ironrdp-core",
  "ironrdp-displaycontrol",
  "ironrdp-dvc",
  "ironrdp-graphics",
@@ -2359,7 +2359,7 @@ version = "0.6.0"
 dependencies = [
  "ironrdp-async",
  "ironrdp-connector",
- "ironrdp-core 0.1.5",
+ "ironrdp-core",
  "ironrdp-pdu",
  "ironrdp-svc",
  "tracing",
@@ -2370,7 +2370,7 @@ name = "ironrdp-ainput"
 version = "0.3.0"
 dependencies = [
  "bitflags 2.9.1",
- "ironrdp-core 0.1.5",
+ "ironrdp-core",
  "ironrdp-dvc",
  "num-derive",
  "num-traits",
@@ -2382,7 +2382,7 @@ version = "0.6.0"
 dependencies = [
  "bytes",
  "ironrdp-connector",
- "ironrdp-core 0.1.5",
+ "ironrdp-core",
  "ironrdp-pdu",
  "tracing",
 ]
@@ -2403,7 +2403,7 @@ version = "0.6.0"
 dependencies = [
  "bytes",
  "ironrdp-connector",
- "ironrdp-core 0.1.5",
+ "ironrdp-core",
  "ironrdp-pdu",
  "tracing",
 ]
@@ -2426,14 +2426,14 @@ dependencies = [
  "ironrdp",
  "ironrdp-cfg",
  "ironrdp-cliprdr-native",
- "ironrdp-core 0.1.5",
+ "ironrdp-core",
  "ironrdp-dvc-pipe-proxy",
  "ironrdp-mstsgu",
  "ironrdp-propertyset",
  "ironrdp-rdcleanpath",
  "ironrdp-rdpfile",
  "ironrdp-rdpsnd-native",
- "ironrdp-tls 0.1.3",
+ "ironrdp-tls",
  "ironrdp-tokio",
  "proc-exit",
  "raw-window-handle",
@@ -2442,7 +2442,7 @@ dependencies = [
  "softbuffer",
  "tap",
  "tokio",
- "tokio-tungstenite 0.27.0",
+ "tokio-tungstenite",
  "tokio-util",
  "tracing",
  "tracing-subscriber",
@@ -2460,7 +2460,7 @@ name = "ironrdp-cliprdr"
 version = "0.3.0"
 dependencies = [
  "bitflags 2.9.1",
- "ironrdp-core 0.1.5",
+ "ironrdp-core",
  "ironrdp-pdu",
  "ironrdp-svc",
  "tracing",
@@ -2470,7 +2470,7 @@ dependencies = [
 name = "ironrdp-cliprdr-format"
 version = "0.1.3"
 dependencies = [
- "ironrdp-core 0.1.5",
+ "ironrdp-core",
  "png",
 ]
 
@@ -2479,7 +2479,7 @@ name = "ironrdp-cliprdr-native"
 version = "0.3.0"
 dependencies = [
  "ironrdp-cliprdr",
- "ironrdp-core 0.1.5",
+ "ironrdp-core",
  "tracing",
  "windows 0.61.3",
 ]
@@ -2489,8 +2489,8 @@ name = "ironrdp-connector"
 version = "0.6.0"
 dependencies = [
  "arbitrary",
- "ironrdp-core 0.1.5",
- "ironrdp-error 0.1.3",
+ "ironrdp-core",
+ "ironrdp-error",
  "ironrdp-pdu",
  "ironrdp-svc",
  "picky",
@@ -2506,23 +2506,14 @@ dependencies = [
 name = "ironrdp-core"
 version = "0.1.5"
 dependencies = [
- "ironrdp-error 0.1.3",
-]
-
-[[package]]
-name = "ironrdp-core"
-version = "0.1.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b2db60a59716a84d09040d29c9e75e81545842510fccb0934c09b28e78b46680"
-dependencies = [
- "ironrdp-error 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "ironrdp-error",
 ]
 
 [[package]]
 name = "ironrdp-displaycontrol"
 version = "0.3.0"
 dependencies = [
- "ironrdp-core 0.1.5",
+ "ironrdp-core",
  "ironrdp-dvc",
  "ironrdp-pdu",
  "ironrdp-svc",
@@ -2533,7 +2524,7 @@ dependencies = [
 name = "ironrdp-dvc"
 version = "0.3.1"
 dependencies = [
- "ironrdp-core 0.1.5",
+ "ironrdp-core",
  "ironrdp-pdu",
  "ironrdp-svc",
  "slab",
@@ -2545,7 +2536,7 @@ name = "ironrdp-dvc-pipe-proxy"
 version = "0.1.0"
 dependencies = [
  "async-trait",
- "ironrdp-core 0.1.5",
+ "ironrdp-core",
  "ironrdp-dvc",
  "ironrdp-pdu",
  "ironrdp-svc",
@@ -2557,12 +2548,6 @@ dependencies = [
 name = "ironrdp-error"
 version = "0.1.3"
 
-[[package]]
-name = "ironrdp-error"
-version = "0.1.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4a9d7794e854eef2f13fdf79c8502bcc567a75a15fd0522885f37739386a4cef"
-
 [[package]]
 name = "ironrdp-futures"
 version = "0.4.0"
@@ -2579,7 +2564,7 @@ dependencies = [
  "arbitrary",
  "ironrdp-cliprdr",
  "ironrdp-cliprdr-format",
- "ironrdp-core 0.1.5",
+ "ironrdp-core",
  "ironrdp-displaycontrol",
  "ironrdp-graphics",
  "ironrdp-pdu",
@@ -2599,7 +2584,7 @@ dependencies = [
  "bytemuck",
  "byteorder",
  "expect-test",
- "ironrdp-core 0.1.5",
+ "ironrdp-core",
  "ironrdp-pdu",
  "lazy_static",
  "num-derive",
@@ -2626,12 +2611,12 @@ dependencies = [
  "http-body-util",
  "hyper",
  "hyper-util",
- "ironrdp-core 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
- "ironrdp-error 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)",
- "ironrdp-tls 0.1.3 (registry+https://github.com/rust-lang/crates.io-index)",
+ "ironrdp-core",
+ "ironrdp-error",
+ "ironrdp-tls",
  "log",
  "tokio",
- "tokio-tungstenite 0.26.2",
+ "tokio-tungstenite",
  "tokio-util",
  "uuid",
 ]
@@ -2645,8 +2630,8 @@ dependencies = [
  "byteorder",
  "der-parser",
  "expect-test",
- "ironrdp-core 0.1.5",
- "ironrdp-error 0.1.3",
+ "ironrdp-core",
+ "ironrdp-error",
  "lazy_static",
  "md-5",
  "num-bigint",
@@ -2683,8 +2668,8 @@ name = "ironrdp-rdpdr"
 version = "0.3.0"
 dependencies = [
  "bitflags 2.9.1",
- "ironrdp-core 0.1.5",
- "ironrdp-error 0.1.3",
+ "ironrdp-core",
+ "ironrdp-error",
  "ironrdp-pdu",
  "ironrdp-svc",
  "tracing",
@@ -2694,7 +2679,7 @@ dependencies = [
 name = "ironrdp-rdpdr-native"
 version = "0.3.0"
 dependencies = [
- "ironrdp-core 0.1.5",
+ "ironrdp-core",
  "ironrdp-pdu",
  "ironrdp-rdpdr",
  "ironrdp-svc",
@@ -2714,7 +2699,7 @@ name = "ironrdp-rdpsnd"
 version = "0.5.0"
 dependencies = [
  "bitflags 2.9.1",
- "ironrdp-core 0.1.5",
+ "ironrdp-core",
  "ironrdp-pdu",
  "ironrdp-svc",
  "tracing",
@@ -2744,7 +2729,7 @@ dependencies = [
  "ironrdp-ainput",
  "ironrdp-async",
  "ironrdp-cliprdr",
- "ironrdp-core 0.1.5",
+ "ironrdp-core",
  "ironrdp-displaycontrol",
  "ironrdp-dvc",
  "ironrdp-graphics",
@@ -2768,10 +2753,10 @@ name = "ironrdp-session"
 version = "0.5.0"
 dependencies = [
  "ironrdp-connector",
- "ironrdp-core 0.1.5",
+ "ironrdp-core",
  "ironrdp-displaycontrol",
  "ironrdp-dvc",
- "ironrdp-error 0.1.3",
+ "ironrdp-error",
  "ironrdp-graphics",
  "ironrdp-pdu",
  "ironrdp-svc",
@@ -2789,7 +2774,7 @@ name = "ironrdp-svc"
 version = "0.4.1"
 dependencies = [
  "bitflags 2.9.1",
- "ironrdp-core 0.1.5",
+ "ironrdp-core",
  "ironrdp-pdu",
 ]
 
@@ -2804,7 +2789,7 @@ dependencies = [
  "ironrdp-cliprdr",
  "ironrdp-cliprdr-format",
  "ironrdp-connector",
- "ironrdp-core 0.1.5",
+ "ironrdp-core",
  "ironrdp-displaycontrol",
  "ironrdp-dvc",
  "ironrdp-fuzzing",
@@ -2833,7 +2818,7 @@ dependencies = [
  "async-trait",
  "ironrdp",
  "ironrdp-async",
- "ironrdp-tls 0.1.3",
+ "ironrdp-tls",
  "ironrdp-tokio",
  "semver",
  "tokio",
@@ -2851,18 +2836,6 @@ dependencies = [
  "x509-cert",
 ]
 
-[[package]]
-name = "ironrdp-tls"
-version = "0.1.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4fc807c143533f41e19bf323e8c7f78995953ce8427d37220dde53906cbd48a3"
-dependencies = [
- "tokio",
- "tokio-native-tls",
- "tokio-rustls",
- "x509-cert",
-]
-
 [[package]]
 name = "ironrdp-tokio"
 version = "0.6.0"
@@ -2892,7 +2865,7 @@ dependencies = [
  "iron-remote-desktop",
  "ironrdp",
  "ironrdp-cliprdr-format",
- "ironrdp-core 0.1.5",
+ "ironrdp-core",
  "ironrdp-futures",
  "ironrdp-propertyset",
  "ironrdp-rdcleanpath",
@@ -5523,24 +5496,6 @@ dependencies = [
  "tokio",
 ]
 
-[[package]]
-name = "tokio-tungstenite"
-version = "0.26.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7a9daff607c6d2bf6c16fd681ccb7eecc83e4e2cdc1ca067ffaadfca5de7f084"
-dependencies = [
- "futures-util",
- "log",
- "native-tls",
- "rustls",
- "rustls-native-certs",
- "rustls-pki-types",
- "tokio",
- "tokio-native-tls",
- "tokio-rustls",
- "tungstenite 0.26.2",
-]
-
 [[package]]
 name = "tokio-tungstenite"
 version = "0.27.0"
@@ -5556,7 +5511,7 @@ dependencies = [
  "tokio",
  "tokio-native-tls",
  "tokio-rustls",
- "tungstenite 0.27.0",
+ "tungstenite",
 ]
 
 [[package]]
@@ -5776,26 +5731,6 @@ version = "0.25.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d2df906b07856748fa3f6e0ad0cbaa047052d4a7dd609e231c4f72cee8c36f31"
 
-[[package]]
-name = "tungstenite"
-version = "0.26.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4793cb5e56680ecbb1d843515b23b6de9a75eb04b66643e256a396d43be33c13"
-dependencies = [
- "bytes",
- "data-encoding",
- "http",
- "httparse",
- "log",
- "native-tls",
- "rand 0.9.2",
- "rustls",
- "rustls-pki-types",
- "sha1",
- "thiserror 2.0.14",
- "utf-8",
-]
-
 [[package]]
 name = "tungstenite"
 version = "0.27.0"

crates/ironrdp-client/src/config.rs

@@ -325,7 +325,7 @@ impl Config {
                 gw_endpoint: gw_addr,
                 gw_user: String::new(),
                 gw_pass: String::new(),
-                server: String::new(), // TODO non-standard port? also dont use here?
+                server: String::new(), // TODO: non-standard port? also dont use here?
             });
         }
 

crates/ironrdp-mstsgu/Cargo.toml

@@ -3,6 +3,7 @@ name = "ironrdp-mstsgu"
 version = "0.0.1"
 readme = "README.md"
 description = "Terminal Services Gateway Server Protocol"
+publish = false # TODO: publish
 edition.workspace = true
 license.workspace = true
 homepage.workspace = true
@@ -11,9 +12,9 @@ authors.workspace = true
 keywords.workspace = true
 categories.workspace = true
 
-#[lib]
-#doctest = false
-#test = false
+[lib]
+doctest = false
+test = false
 
 [features]
 default = []
@@ -21,20 +22,20 @@ rustls = ["ironrdp-tls/rustls", "tokio-tungstenite/rustls-tls-native-roots"]
 native-tls = ["ironrdp-tls/native-tls", "tokio-tungstenite/native-tls"]
 
 [dependencies]
-bitflags = "2.9"
-ironrdp-core = { version = "0.1", features = ["std"] }
-ironrdp-error = { version = "0.1" }
-tokio = { version = "1.43", features = ["macros", "rt"] }
-tokio-util = { version = "0.7" }
-tokio-tungstenite = { version = "0.26" }
-ironrdp-tls = { "version" = "0.1.3" }
-hyper = { version = "1.6", features = ["client", "http1"] }
-hyper-util = { version = "0.1", features = ["tokio"] }
-http-body-util = { version = "0.1" }
-futures-util = "0.3"
-log = "0.4"
 base64 = "0.22"
-uuid = { version = "1.16.0", features = ["v4"] }
+bitflags = "2.9"
+futures-util = "0.3"
+http-body-util = { version = "0.1" }
+hyper-util = { version = "0.1", features = ["tokio"] }
+hyper = { version = "1.6", features = ["client", "http1"] }
+ironrdp-core = { path = "../ironrdp-core", version = "0.1", features = ["std"] }
+ironrdp-error = { path = "../ironrdp-error", version = "0.1" }
+ironrdp-tls = { path = "../ironrdp-tls", version = "0.1" }
+log = "0.4"
+tokio-tungstenite = { version = "0.27" }
+tokio-util = { version = "0.7" }
+tokio = { version = "1.43", features = ["macros", "rt"] }
+uuid = { version = "1.16", features = ["v4"] }
 
 [lints]
 workspace = true

crates/ironrdp-mstsgu/README.md

@@ -0,0 +1,11 @@
+# IronRDP MS-TSGU
+
+[Terminal Services Gateway Server Protocol][MS-TSGU] implementation for IronRDP.
+
+This crate
+- implements an MVP state needed to connect through Microsoft RD Gateway,
+- only supports the HTTPS protocol with WebSocket (and not the legacy HTTP, HTTP-RPC or UDP protocols),
+- does not implement reconnection/reauthentication, and
+- only supports basic auth.
+
+[MS-TSGU]: https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-tsgu/0007d661-a86d-4e8f-89f7-7f77f8824188

crates/ironrdp-mstsgu/src/lib.rs

@@ -1,8 +1,11 @@
-//! [MS-TSGU] https://learn.microsoft.com/en-us/openspecs/windows_protocols/ms-tsgu/0007d661-a86d-4e8f-89f7-7f77f8824188
-//! * This implements a MVP (in terms of recentness) state needed to connect through microsoft rdp gateway.
-//! * This only supports the HTTPS protocol with Websocket (and not the legacy HTTP, HTTP-RPC or UDP protocols).
-//! * This does not implement reconnection/reauthentication.
-//! * This only supports basic auth.
+#![cfg_attr(doc, doc = include_str!("../README.md"))]
+#![doc(html_logo_url = "https://cdnweb.devolutions.net/images/projects/devolutions/logos/devolutions-icon-shadow.svg")]
+
+#[macro_use]
+mod macros;
+
+mod proto;
+
 use core::fmt;
 use core::fmt::Display;
 use core::pin::Pin;
@@ -22,17 +25,16 @@ use tokio::io::{AsyncRead, AsyncWrite};
 use tokio::net::TcpStream;
 use tokio::sync::oneshot;
 use tokio_tungstenite::tungstenite::handshake::client::generate_key;
-use tokio_tungstenite::tungstenite::http::{self};
+use tokio_tungstenite::tungstenite::http;
 use tokio_tungstenite::tungstenite::protocol::Role;
 use tokio_tungstenite::tungstenite::Message;
 use tokio_tungstenite::WebSocketStream;
+use tokio_util::sync::PollSender;
 
-mod proto;
-use proto::{
+use self::proto::{
     ChannelPkt, ChannelResp, DataPkt, HandshakeReqPkt, HandshakeRespPkt, HttpCapsTy, KeepalivePkt, PktHdr, PktTy,
     TunnelAuthPkt, TunnelAuthRespPkt, TunnelReqPkt, TunnelRespPkt,
 };
-use tokio_util::sync::PollSender;
 
 #[derive(Clone, Debug)]
 pub struct GwConnectTarget {
@@ -50,9 +52,10 @@ type Error = ironrdp_error::Error<GwErrorKind>;
 pub enum GwErrorKind {
     InvalidGwTarget,
     Connect,
-    PacketEOF,
+    PacketEof,
     UnsupportedFeature,
     Custom,
+    Encode,
     Decode,
 }
 
@@ -74,12 +77,13 @@ impl GwErrorExt for ironrdp_error::Error<GwErrorKind> {
 impl Display for GwErrorKind {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
         let x = match self {
-            GwErrorKind::InvalidGwTarget => "Invalid GW Target",
-            GwErrorKind::Connect => "Connection error",
-            GwErrorKind::PacketEOF => "PacketEOF",
-            GwErrorKind::UnsupportedFeature => "Unsupported feature",
-            GwErrorKind::Custom => "Custom",
-            GwErrorKind::Decode => "Decode",
+            GwErrorKind::InvalidGwTarget => "invalid GW Target",
+            GwErrorKind::Connect => "connection error",
+            GwErrorKind::PacketEof => "PacketEOF",
+            GwErrorKind::UnsupportedFeature => "unsupported feature",
+            GwErrorKind::Custom => "custom",
+            GwErrorKind::Encode => "encode",
+            GwErrorKind::Decode => "decode",
         };
         f.write_str(x)
     }
@@ -87,14 +91,6 @@ impl Display for GwErrorKind {
 
 impl core::error::Error for GwErrorKind {}
 
-/// Creates a `ConnectorError` with `Custom` kind and a source error attached to it
-#[macro_export]
-macro_rules! custom_err {
-    ( $context:expr, $source:expr $(,)? ) => {{
-        <$crate::Error as $crate::GwErrorExt>::custom($context, $source)
-    }};
-}
-
 struct GwConn {
     client_name: String,
     target: GwConnectTarget,
@@ -270,13 +266,15 @@ impl GwConn {
         let mut buf = [0u8; 4096];
         let pos = {
             let mut cur = WriteCursor::new(&mut buf);
-            payload.encode(&mut cur).unwrap();
+            payload
+                .encode(&mut cur)
+                .map_err(|e| Error::new("packet encode", GwErrorKind::Encode).with_source(e))?;
             cur.pos()
         };
         self.ws_sink
             .send(Message::Binary(Bytes::copy_from_slice(&buf[..pos])))
             .await
-            .map_err(|e| custom_err!("WS Send error", e))?;
+            .map_err(|e| custom_err!("WebSocket send error", e))?;
         Ok(())
     }
 
@@ -292,7 +290,7 @@ impl GwConn {
 
         let hdr = PktHdr::decode(&mut cur).map_err(|_| Error::new("PktHdr", GwErrorKind::Decode))?;
         if cur.len() != hdr.length as usize - hdr.size() {
-            return Err(Error::new("read_packet", GwErrorKind::PacketEOF));
+            return Err(Error::new("read_packet", GwErrorKind::PacketEof));
         }
 
         Ok((hdr, msg.split_off(cur.pos())))

crates/ironrdp-mstsgu/src/macros.rs

@@ -0,0 +1,7 @@
+/// Creates a [`crate::Error`] with `Custom` kind and a source error attached to it
+#[macro_export]
+macro_rules! custom_err {
+    ( $context:expr, $source:expr $(,)? ) => {{
+        <$crate::Error as $crate::GwErrorExt>::custom($context, $source)
+    }};
+}

crates/ironrdp-mstsgu/src/proto.rs

@@ -1,6 +1,7 @@
 use bitflags::bitflags;
 use ironrdp_core::{
-    ensure_fixed_part_size, ensure_size, unsupported_value_err, Decode, Encode, ReadCursor, WriteCursor,
+    cast_int, cast_length, ensure_fixed_part_size, ensure_size, unsupported_value_err, Decode, Encode, ReadCursor,
+    WriteCursor,
 };
 
 bitflags! {
@@ -70,7 +71,7 @@ pub(crate) struct PktHdr {
 }
 
 impl PktHdr {
-    const FIXED_PART_SIZE: usize = 4 /* ty */ + 2/* _reserved */ + 2 /* length */;
+    const FIXED_PART_SIZE: usize = 4 /* ty */ + 2 /* _reserved */ + 2 /* length */;
 }
 
 impl Encode for PktHdr {
@@ -89,7 +90,7 @@ impl Encode for PktHdr {
     }
 
     fn size(&self) -> usize {
-        8
+        Self::FIXED_PART_SIZE
     }
 }
 
@@ -123,7 +124,7 @@ impl Encode for HandshakeReqPkt {
 
         let hdr = PktHdr {
             ty: PktTy::HandshakeReq,
-            length: u32::try_from(self.size()).unwrap(),
+            length: u32::try_from(self.size()).expect("handshake packet size fits in u32"),
             ..PktHdr::default()
         };
         hdr.encode(dst)?;
@@ -141,7 +142,7 @@ impl Encode for HandshakeReqPkt {
     }
 
     fn size(&self) -> usize {
-        PktHdr::default().size() + 6
+        PktHdr::FIXED_PART_SIZE + 6
     }
 }
 
@@ -191,7 +192,7 @@ impl Encode for TunnelReqPkt {
 
         let hdr = PktHdr {
             ty: PktTy::TunnelCreate,
-            length: u32::try_from(self.size()).unwrap(),
+            length: u32::try_from(self.size()).expect("tunnel request packet size fits in u32"),
             ..PktHdr::default()
         };
         hdr.encode(dst)?;
@@ -303,14 +304,16 @@ impl Encode for ExtendedAuthPkt {
 
         let hdr = PktHdr {
             ty: PktTy::ExtendedAuth,
-            length: u32::try_from(self.size()).unwrap(),
+            length: cast_int!("packet length", self.size())?,
             ..PktHdr::default()
         };
         hdr.encode(dst)?;
 
         dst.write_u32(self.error_code);
-        dst.write_u16(u16::try_from(self.blob.len()).unwrap());
+        let blob_len: u16 = cast_int!("blob length", self.blob.len())?;
+        dst.write_u16(blob_len);
         dst.write_slice(&self.blob);
+
         Ok(())
     }
 
@@ -349,17 +352,23 @@ impl Encode for TunnelAuthPkt {
 
         let hdr = PktHdr {
             ty: PktTy::TunnelAuth,
-            length: u32::try_from(self.size()).unwrap(),
+            length: cast_int!("packet length", self.size())?,
             ..PktHdr::default()
         };
         hdr.encode(dst)?;
 
         dst.write_u16(self.fields_present);
-        dst.write_u16(u16::try_from(2 * (self.client_name.len() + 1)).unwrap());
+
+        let client_name_len = self.client_name.encode_utf16().count() * 2 + 2; // Add 2 to account for a null terminator (0x0000).
+        let client_name_len: u16 = cast_int!("client name length", client_name_len)?;
+        dst.write_u16(client_name_len);
+
         for c in self.client_name.encode_utf16() {
             dst.write_u16(c);
         }
+
         dst.write_u16(0);
+
         Ok(())
     }
 
@@ -409,19 +418,22 @@ impl Encode for ChannelPkt {
 
         let hdr = PktHdr {
             ty: PktTy::ChannelCreate,
-            length: u32::try_from(self.size()).unwrap(),
+            length: cast_int!("packet length", self.size())?,
             ..PktHdr::default()
         };
         hdr.encode(dst)?;
 
-        dst.write_u8(u8::try_from(self.resources.len()).unwrap());
+        let resources_count: u8 = cast_length!("resources count", self.resources.len())?;
+        dst.write_u8(resources_count);
         dst.write_u8(0); // alt_names
         dst.write_u16(self.port);
         dst.write_u16(self.protocol);
 
         // 2.2.10.3 HTTP_CHANNEL_PACKET_VARIABLE
         for res in &self.resources {
-            dst.write_u16(u16::try_from(2 * (res.len() + 1)).unwrap());
+            let res_utf16_len = res.encode_utf16().count() * 2 + 2; // Add 2 to account for a null terminator (0x0000).
+            let res_len: u16 = cast_int!("resource name UTF-16 length", res_utf16_len)?;
+            dst.write_u16(res_len);
             for b in res.encode_utf16() {
                 dst.write_u16(b);
             }
@@ -496,11 +508,12 @@ impl Encode for DataPkt<'_> {
 
         let hdr = PktHdr {
             ty: PktTy::Data,
-            length: u32::try_from(self.size()).unwrap(),
+            length: cast_int!("packet length", self.size())?,
             ..PktHdr::default()
         };
         hdr.encode(dst)?;
-        dst.write_u16(u16::try_from(self.data.len()).unwrap());
+        let data_len: u16 = cast_int!("data payload length", self.data.len())?;
+        dst.write_u16(data_len);
         dst.write_slice(self.data);
         Ok(())
     }
@@ -531,7 +544,7 @@ impl Encode for KeepalivePkt {
     fn encode(&self, dst: &mut WriteCursor<'_>) -> ironrdp_core::EncodeResult<()> {
         let hdr = PktHdr {
             ty: PktTy::Keepalive,
-            length: u32::try_from(self.size()).unwrap(),
+            length: u32::try_from(self.size()).expect("keepalive packet size fits in u32"),
             ..PktHdr::default()
         };
         hdr.encode(dst)