refactor(header): Allow compilation on 32 bit architectures

- Don't assume that usize is equivalant to a u64
- Require 32-bit or 64-bit architecture at compile time

BREAKING CHANGE: this changes the data_len field in MsgHeader from usize
to u32

src/connections.rs

@@ -322,7 +322,7 @@ async fn handle_endpoint_verification_req(
         Ok(Ok(WireMsg::EndpointEchoResp(_)))
     );
 
-    let message = WireMsg::EndpointVerficationResp(verified);
+    let message = WireMsg::EndpointVerificationResp(verified);
     message.write_to_stream(send_stream).await?;
     trace!("Responded to Endpoint verification request");
 

src/endpoint.rs

@@ -146,7 +146,7 @@ impl Endpoint {
                 send.send(WireMsg::EndpointVerificationReq(addr)).await?;
                 let response = WireMsg::read_from_stream(&mut recv.quinn_recv_stream).await?;
                 match response {
-                    WireMsg::EndpointVerficationResp(valid) => {
+                    WireMsg::EndpointVerificationResp(valid) => {
                         if valid {
                             info!("Endpoint verification successful! {} is reachable.", addr);
                         } else {
@@ -195,7 +195,7 @@ impl Endpoint {
         self.public_addr.unwrap_or(self.local_addr)
     }
 
-    /// Get our connection adddress to give to others for them to connect to us.
+    /// Get our connection address to give to others for them to connect to us.
     ///
     /// Attempts to use UPnP to automatically find the public endpoint and forward a port.
     /// Will use hard coded contacts to ask for our endpoint. If no contact is given then we'll

src/error.rs

@@ -22,7 +22,7 @@ pub enum Error {
     /// of the peers provided as a list of contacts.
     #[error("Network bootstrap failed")]
     BootstrapFailure,
-    /// No peers/contects found in the bootstrap nodes list.
+    /// No peers/contacts found in the bootstrap nodes list.
     #[error("No nodes/peers found defined for bootstrapping")]
     EmptyBootstrapNodesList,
     /// The path provided is not valid for the operation.
@@ -55,7 +55,7 @@ pub enum Error {
     NoEchoServerEndpointDefined,
     /// Timeout occurred when awaiting for a response from
     /// any of the peers contacted for the echo service.
-    #[error("No response reeived from echo services")]
+    #[error("No response received from echo services")]
     NoEchoServiceResponse,
     /// Failure occurred when sending an echo request.
     #[error("{0}")]
@@ -70,7 +70,7 @@ pub enum Error {
     #[error("Base64 decode")]
     Base64Decode(#[from] base64::DecodeError),
     /// An error occurred which could be resolved by changing some config value.
-    #[error("Configuration {}", 0)]
+    #[error("Configuration {0}")]
     Configuration(String),
     /// The message type flag decoded in an incoming stream is invalid/unsupported.
     #[error("Invalid message type flag found in message's header: {0}")]
@@ -79,7 +79,7 @@ pub enum Error {
     #[error("Stream write error")]
     StreamWrite(#[from] quinn::WriteError),
     /// The expected amount of message bytes couldn't be read from the stream.
-    #[error("Failed to read expected nummber of message bytes: {}", 0)]
+    #[error("Failed to read expected number of message bytes: {0}")]
     StreamRead(#[from] quinn::ReadExactError),
     /// Failure when trying to map a new port using IGD for automatic port forwarding.
     #[error("Could not use IGD for automatic port forwarding")]
@@ -95,7 +95,7 @@ pub enum Error {
     IgdNotSupported,
     /// An error was encountered when trying to either generate
     /// or serialise a self-signed certificate.
-    #[error("Self-signed certificate generation error: {}", 0)]
+    #[error("Self-signed certificate generation error: {0}")]
     CertificateGen(#[from] rcgen::RcgenError),
     /// Response message received contains an empty payload.
     #[error("Empty response message received from peer")]
@@ -112,4 +112,7 @@ pub enum Error {
     /// Missing connection
     #[error("No connection to the dest peer")]
     MissingConnection,
+    /// A supposedly impossible internal error occurred
+    #[error("Unexpected internal error: {0}")]
+    UnexpectedError(String),
 }

src/wire_msg.rs

@@ -14,6 +14,7 @@ use crate::{
 use bytes::Bytes;
 use log::trace;
 use serde::{Deserialize, Serialize};
+use std::convert::TryFrom;
 use std::{fmt, net::SocketAddr};
 
 const MSG_HEADER_LEN: usize = 9;
@@ -25,7 +26,7 @@ pub enum WireMsg {
     EndpointEchoReq,
     EndpointEchoResp(SocketAddr),
     EndpointVerificationReq(SocketAddr),
-    EndpointVerficationResp(bool),
+    EndpointVerificationResp(bool),
     UserMsg(Bytes),
 }
 
@@ -41,7 +42,22 @@ impl WireMsg {
 
         let msg_header = MsgHeader::from_bytes(header_bytes);
         log::debug!("reading data of length: {}", msg_header.data_len());
-        let mut data: Vec<u8> = vec![0; msg_header.data_len()];
+        // https://github.com/rust-lang/rust/issues/70460 for work on a cleaner alternative:
+        #[cfg(not(any(target_pointer_width = "32", target_pointer_width = "64")))]
+        {
+            compile_error!("You need an architecture capable of addressing 32-bit pointers");
+        }
+        let data_length = match usize::try_from(msg_header.data_len()) {
+            Ok(s) => s,
+            Err(_) => {
+                return Err(Error::UnexpectedError(format!(
+                    // this should never happen due to preceding compilation error
+                    "unable to convert u32 '{}' to usize",
+                    msg_header.data_len()
+                )));
+            }
+        };
+        let mut data: Vec<u8> = vec![0; data_length];
         let msg_flag = msg_header.usr_msg_flag();
 
         recv.read_exact(&mut data).await?;
@@ -91,7 +107,7 @@ impl fmt::Display for WireMsg {
             WireMsg::EndpointVerificationReq(ref sa) => {
                 write!(f, "WireMsg::EndpointVerificationReq({})", sa)
             }
-            WireMsg::EndpointVerficationResp(valid) => write!(
+            WireMsg::EndpointVerificationResp(valid) => write!(
                 f,
                 "WireMsg::EndpointEchoResp({})",
                 if valid { "Valid" } else { "Invalid" }
@@ -107,27 +123,26 @@ impl fmt::Display for WireMsg {
 #[derive(Debug)]
 struct MsgHeader {
     version: u16,
-    data_len: usize,
+    data_len: u32,
     usr_msg_flag: u8,
     #[allow(unused)]
     reserved: [u8; 2],
 }
 
 impl MsgHeader {
     pub fn new(msg: &Bytes, usr_msg_flag: u8) -> Result<Self> {
-        let data_len = msg.len();
-        if data_len > u32::MAX as usize {
-            return Err(Error::MaxLengthExceeded(data_len));
+        match u32::try_from(msg.len()) {
+            Err(_) => Err(Error::MaxLengthExceeded(msg.len())),
+            Ok(data_len) => Ok(Self {
+                version: MSG_PROTOCOL_VERSION,
+                data_len,
+                usr_msg_flag,
+                reserved: [0, 0],
+            }),
         }
-        Ok(Self {
-            version: MSG_PROTOCOL_VERSION,
-            data_len,
-            usr_msg_flag,
-            reserved: [0, 0],
-        })
     }
 
-    pub fn data_len(&self) -> usize {
+    pub fn data_len(&self) -> u32 {
         self.data_len
     }
 
@@ -141,10 +156,10 @@ impl MsgHeader {
         [
             version[0],
             version[1],
-            data_len[4],
-            data_len[5],
-            data_len[6],
-            data_len[7],
+            data_len[0],
+            data_len[1],
+            data_len[2],
+            data_len[3],
             self.usr_msg_flag,
             0,
             0,
@@ -153,7 +168,7 @@ impl MsgHeader {
 
     pub fn from_bytes(bytes: [u8; MSG_HEADER_LEN]) -> Self {
         let version = u16::from_be_bytes([bytes[0], bytes[1]]);
-        let data_len = usize::from_be_bytes([0, 0, 0, 0, bytes[2], bytes[3], bytes[4], bytes[5]]);
+        let data_len = u32::from_be_bytes([bytes[2], bytes[3], bytes[4], bytes[5]]);
         let usr_msg_flag = bytes[6];
         Self {
             version,