Fix warnings

Bumps [mio](https://github.com/tokio-rs/mio) from 0.8.10 to 0.8.11.
- [Release notes](https://github.com/tokio-rs/mio/releases)
- [Changelog](https://github.com/tokio-rs/mio/blob/master/CHANGELOG.md)
- [Commits](https://github.com/tokio-rs/mio/compare/v0.8.10...v0.8.11)

---
updated-dependencies:
- dependency-name: mio
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.github/workflows/test.yml

@@ -75,8 +75,8 @@ jobs:
             rust: stable
           - name: beta
             rust: beta
-          - name: 1.65.0
-            rust: 1.65.0
+          - name: '1.70'
+            rust: '1.70'
 
     steps:
       - name: Checkout

.gitignore

@@ -4,4 +4,3 @@
 lettre.sublime-*
 lettre.iml
 target/
-/Cargo.lock

CHANGELOG.md

@@ -1,3 +1,49 @@
+<a name="v0.11.4"></a>
+### v0.11.4 (2024-01-28)
+
+#### Bug fixes
+
+* Percent decode credentials in SMTP connect URL ([#932], [#934])
+* Fix mimebody DKIM body-hash computation ([#923])
+
+[#923]: https://github.com/lettre/lettre/pull/923
+[#932]: https://github.com/lettre/lettre/pull/932
+[#934]: https://github.com/lettre/lettre/pull/934
+
+<a name="v0.11.3"></a>
+### v0.11.3 (2024-01-02)
+
+#### Features
+
+* Derive `Clone` for `FileTransport` and `AsyncFileTransport` ([#924])
+* Derive `Debug` for `SmtpTransport` ([#925])
+
+#### Misc
+
+* Upgrade `rustls` to v0.22 ([#921])
+* Drop once_cell dependency in favor of OnceLock from std ([#928])
+
+[#921]: https://github.com/lettre/lettre/pull/921
+[#924]: https://github.com/lettre/lettre/pull/924
+[#925]: https://github.com/lettre/lettre/pull/925
+[#928]: https://github.com/lettre/lettre/pull/928
+
+<a name="v0.11.2"></a>
+### v0.11.2 (2023-11-23)
+
+#### Upgrade notes
+
+* MSRV is now 1.70 ([#916])
+
+#### Misc
+
+* Bump `idna` to v0.5 ([#918])
+* Bump `boring` and `tokio-boring` to v4 ([#915])
+
+[#915]: https://github.com/lettre/lettre/pull/915
+[#916]: https://github.com/lettre/lettre/pull/916
+[#918]: https://github.com/lettre/lettre/pull/918
+
 <a name="v0.11.1"></a>
 ### v0.11.1 (2023-10-24)
 
@@ -198,7 +244,7 @@ Several breaking changes were made between 0.9 and 0.10, but changes should be s
 * Update `hostname` to 0.3
 * Update to `nom` 6
 * Replace `log` with `tracing`
-* Move CI to Github Actions
+* Move CI to GitHub Actions
 * Use criterion for benchmarks
 
 <a name="v0.9.2"></a>

Cargo.toml

@@ -1,7 +1,7 @@
 [package]
 name = "lettre"
 # remember to update html_root_url and README.md (Cargo.toml example and deps.rs badge)
-version = "0.11.1"
+version = "0.11.4"
 description = "Email client"
 readme = "README.md"
 homepage = "https://lettre.rs"
@@ -11,7 +11,7 @@ authors = ["Alexis Mousset <contact@amousset.me>", "Paolo Barbolini <paolo@paolo
 categories = ["email", "network-programming"]
 keywords = ["email", "smtp", "mailer", "message", "sendmail"]
 edition = "2021"
-rust-version = "1.65"
+rust-version = "1.70"
 
 [badges]
 is-it-maintained-issue-resolution = { repository = "lettre/lettre" }
@@ -20,8 +20,7 @@ maintenance = { status = "actively-developed" }
 
 [dependencies]
 chumsky = "0.9"
-idna = "0.4"
-once_cell = { version = "1", optional = true }
+idna = "0.5"
 tracing = { version = "0.1.16", default-features = false, features = ["std"], optional = true } # feature
 
 # builder
@@ -29,7 +28,7 @@ httpdate = { version = "1", optional = true }
 mime = { version = "0.3.4", optional = true }
 fastrand = { version = "2.0", optional = true }
 quoted_printable = { version = "0.5", optional = true }
-base64 = { version = "0.21", optional = true }
+base64 = { version = "0.22", optional = true }
 email-encoding = { version = "0.2", optional = true }
 
 # file transport
@@ -42,14 +41,15 @@ nom = { version = "7", optional = true }
 hostname = { version = "0.3", optional = true } # feature
 socket2 = { version = "0.5.1", optional = true }
 url = { version = "2.4", optional = true }
+percent-encoding = { version = "2.3", optional = true }
 
 ## tls
 native-tls = { version = "0.2.5", optional = true } # feature
-rustls = { version = "0.21", features = ["dangerous_configuration"], optional = true }
-rustls-pemfile = { version = "1", optional = true }
-rustls-native-certs = { version = "0.6.2", optional = true }
-webpki-roots = { version = "0.25", optional = true }
-boring = { version = "3", optional = true }
+rustls = { version = "0.22.1", optional = true }
+rustls-pemfile = { version = "2", optional = true }
+rustls-native-certs = { version = "0.7", optional = true }
+webpki-roots = { version = "0.26", optional = true }
+boring = { version = "4", optional = true }
 
 # async
 futures-io = { version = "0.3.7", optional = true }
@@ -59,13 +59,13 @@ async-trait = { version = "0.1", optional = true }
 ## async-std
 async-std = { version = "1.8", optional = true }
 #async-native-tls = { version = "0.3.3", optional = true }
-futures-rustls = { version = "0.24", optional = true }
+futures-rustls = { version = "0.25", optional = true }
 
 ## tokio
 tokio1_crate = { package = "tokio", version = "1", optional = true }
 tokio1_native_tls_crate = { package = "tokio-native-tls", version = "0.3", optional = true }
-tokio1_rustls = { package = "tokio-rustls", version = "0.24", optional = true }
-tokio1_boring = { package = "tokio-boring", version = "3", optional = true }
+tokio1_rustls = { package = "tokio-rustls", version = "0.25", optional = true }
+tokio1_boring = { package = "tokio-boring", version = "4", optional = true }
 
 ## dkim
 sha2 = { version = "0.10", optional = true, features = ["oid"] }
@@ -85,7 +85,7 @@ walkdir = "2"
 tokio1_crate = { package = "tokio", version = "1", features = ["macros", "rt-multi-thread"] }
 async-std = { version = "1.8", features = ["attributes"] }
 serde_json = "1"
-maud = "0.25"
+maud = "0.26"
 
 [[bench]]
 harness = false
@@ -104,7 +104,7 @@ mime03 = ["dep:mime"]
 file-transport = ["dep:uuid", "tokio1_crate?/fs", "tokio1_crate?/io-util"]
 file-transport-envelope = ["serde", "dep:serde_json", "file-transport"]
 sendmail-transport = ["tokio1_crate?/process", "tokio1_crate?/io-util", "async-std?/unstable"]
-smtp-transport = ["dep:base64", "dep:nom", "dep:socket2", "dep:once_cell", "dep:url", "tokio1_crate?/rt", "tokio1_crate?/time", "tokio1_crate?/net"]
+smtp-transport = ["dep:base64", "dep:nom", "dep:socket2", "dep:url", "dep:percent-encoding", "tokio1_crate?/rt", "tokio1_crate?/time", "tokio1_crate?/net"]
 
 pool = ["dep:futures-util"]
 

README.md

@@ -28,8 +28,8 @@
 </div>
 
 <div align="center">
-  <a href="https://deps.rs/crate/lettre/0.11.1">
-    <img src="https://deps.rs/crate/lettre/0.11.1/status.svg"
+  <a href="https://deps.rs/crate/lettre/0.11.4">
+    <img src="https://deps.rs/crate/lettre/0.11.4/status.svg"
       alt="dependency status" />
   </a>
 </div>
@@ -53,12 +53,12 @@ Lettre does not provide (for now):
 ## Supported Rust Versions
 
 Lettre supports all Rust versions released in the last 6 months. At the time of writing
-the minimum supported Rust version is 1.65, but this could change at any time either from
+the minimum supported Rust version is 1.70, but this could change at any time either from
 one of our dependencies bumping their MSRV or by a new patch release of lettre.
 
 ## Example
 
-This library requires Rust 1.65 or newer.
+This library requires Rust 1.70 or newer.
 To use this library, add the following to your `Cargo.toml`:
 
 ```toml

src/executor.rs

@@ -134,7 +134,7 @@ impl Executor for Tokio1Executor {
         #[allow(clippy::match_single_binding)]
         let tls_parameters = match tls {
             #[cfg(any(feature = "tokio1-native-tls", feature = "tokio1-rustls-tls"))]
-            Tls::Wrapper(ref tls_parameters) => Some(tls_parameters.clone()),
+            Tls::Wrapper(tls_parameters) => Some(tls_parameters.clone()),
             _ => None,
         };
         #[allow(unused_mut)]
@@ -149,13 +149,13 @@ impl Executor for Tokio1Executor {
 
         #[cfg(any(feature = "tokio1-native-tls", feature = "tokio1-rustls-tls"))]
         match tls {
-            Tls::Opportunistic(ref tls_parameters) => {
+            Tls::Opportunistic(tls_parameters) => {
                 if conn.can_starttls() {
-                    conn.starttls(tls_parameters.clone(), hello_name).await?;
+                    conn = conn.starttls(tls_parameters.clone(), hello_name).await?;
                 }
             }
-            Tls::Required(ref tls_parameters) => {
-                conn.starttls(tls_parameters.clone(), hello_name).await?;
+            Tls::Required(tls_parameters) => {
+                conn = conn.starttls(tls_parameters.clone(), hello_name).await?;
             }
             _ => (),
         }
@@ -231,7 +231,7 @@ impl Executor for AsyncStd1Executor {
         #[allow(clippy::match_single_binding)]
         let tls_parameters = match tls {
             #[cfg(any(feature = "async-std1-native-tls", feature = "async-std1-rustls-tls"))]
-            Tls::Wrapper(ref tls_parameters) => Some(tls_parameters.clone()),
+            Tls::Wrapper(tls_parameters) => Some(tls_parameters.clone()),
             _ => None,
         };
         #[allow(unused_mut)]
@@ -245,13 +245,13 @@ impl Executor for AsyncStd1Executor {
 
         #[cfg(any(feature = "async-std1-native-tls", feature = "async-std1-rustls-tls"))]
         match tls {
-            Tls::Opportunistic(ref tls_parameters) => {
+            Tls::Opportunistic(tls_parameters) => {
                 if conn.can_starttls() {
-                    conn.starttls(tls_parameters.clone(), hello_name).await?;
+                    conn = conn.starttls(tls_parameters.clone(), hello_name).await?;
                 }
             }
-            Tls::Required(ref tls_parameters) => {
-                conn.starttls(tls_parameters.clone(), hello_name).await?;
+            Tls::Required(tls_parameters) => {
+                conn = conn.starttls(tls_parameters.clone(), hello_name).await?;
             }
             _ => (),
         }

src/lib.rs

@@ -6,7 +6,7 @@
 //! * Secure defaults
 //! * Async support
 //!
-//! Lettre requires Rust 1.65 or newer.
+//! Lettre requires Rust 1.70 or newer.
 //!
 //! ## Features
 //!
@@ -109,7 +109,7 @@
 //! [mime 0.3]: https://docs.rs/mime/0.3
 //! [DKIM]: https://datatracker.ietf.org/doc/html/rfc6376
 
-#![doc(html_root_url = "https://docs.rs/crate/lettre/0.11.1")]
+#![doc(html_root_url = "https://docs.rs/crate/lettre/0.11.4")]
 #![doc(html_favicon_url = "https://lettre.rs/favicon.ico")]
 #![doc(html_logo_url = "https://avatars0.githubusercontent.com/u/15113230?v=4")]
 #![forbid(unsafe_code)]

src/message/dkim.rs

@@ -2,7 +2,6 @@ use std::{
     borrow::Cow,
     error::Error as StdError,
     fmt::{self, Display},
-    iter::IntoIterator,
     time::SystemTime,
 };
 

src/message/mailbox/types.rs

@@ -88,7 +88,7 @@ impl Mailbox {
 
 impl Display for Mailbox {
     fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
-        if let Some(ref name) = self.name {
+        if let Some(name) = &self.name {
             let name = name.trim();
             if !name.is_empty() {
                 write_word(f, name)?;

src/message/mimebody.rs

@@ -17,6 +17,16 @@ pub(super) enum Part {
     Multi(MultiPart),
 }
 
+impl Part {
+    #[cfg(feature = "dkim")]
+    pub(super) fn format_body(&self, out: &mut Vec<u8>) {
+        match self {
+            Part::Single(part) => part.format_body(out),
+            Part::Multi(part) => part.format_body(out),
+        }
+    }
+}
+
 impl EmailFormat for Part {
     fn format(&self, out: &mut Vec<u8>) {
         match self {
@@ -132,6 +142,12 @@ impl SinglePart {
         self.format(&mut out);
         out
     }
+
+    /// Format only the signlepart body
+    fn format_body(&self, out: &mut Vec<u8>) {
+        out.extend_from_slice(&self.body);
+        out.extend_from_slice(b"\r\n");
+    }
 }
 
 impl EmailFormat for SinglePart {
@@ -139,8 +155,7 @@ impl EmailFormat for SinglePart {
         write!(out, "{}", self.headers)
             .expect("A Write implementation panicked while formatting headers");
         out.extend_from_slice(b"\r\n");
-        out.extend_from_slice(&self.body);
-        out.extend_from_slice(b"\r\n");
+        self.format_body(out);
     }
 }
 
@@ -373,14 +388,9 @@ impl MultiPart {
         self.format(&mut out);
         out
     }
-}
-
-impl EmailFormat for MultiPart {
-    fn format(&self, out: &mut Vec<u8>) {
-        write!(out, "{}", self.headers)
-            .expect("A Write implementation panicked while formatting headers");
-        out.extend_from_slice(b"\r\n");
 
+    /// Format only the multipart body
+    fn format_body(&self, out: &mut Vec<u8>) {
         let boundary = self.boundary();
 
         for part in &self.parts {
@@ -396,6 +406,15 @@ impl EmailFormat for MultiPart {
     }
 }
 
+impl EmailFormat for MultiPart {
+    fn format(&self, out: &mut Vec<u8>) {
+        write!(out, "{}", self.headers)
+            .expect("A Write implementation panicked while formatting headers");
+        out.extend_from_slice(b"\r\n");
+        self.format_body(out);
+    }
+}
+
 #[cfg(test)]
 mod test {
     use pretty_assertions::assert_eq;

src/message/mod.rs

@@ -525,7 +525,7 @@ impl Message {
     pub(crate) fn body_raw(&self) -> Vec<u8> {
         let mut out = Vec::new();
         match &self.body {
-            MessageBody::Mime(p) => p.format(&mut out),
+            MessageBody::Mime(p) => p.format_body(&mut out),
             MessageBody::Raw(r) => out.extend_from_slice(r),
         };
         out.extend_from_slice(b"\r\n");

src/transport/file/error.rs

@@ -54,7 +54,7 @@ impl fmt::Debug for Error {
 
         builder.field("kind", &self.inner.kind);
 
-        if let Some(ref source) = self.inner.source {
+        if let Some(source) = &self.inner.source {
             builder.field("source", source);
         }
 
@@ -70,7 +70,7 @@ impl fmt::Display for Error {
             Kind::Envelope => f.write_str("internal client error")?,
         };
 
-        if let Some(ref e) = self.inner.source {
+        if let Some(e) = &self.inner.source {
             write!(f, ": {e}")?;
         }
 

src/transport/file/mod.rs

@@ -157,7 +157,7 @@ mod error;
 type Id = String;
 
 /// Writes the content and the envelope information to a file
-#[derive(Debug)]
+#[derive(Debug, Clone)]
 #[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 #[cfg_attr(docsrs, doc(cfg(feature = "file-transport")))]
 pub struct FileTransport {
@@ -167,7 +167,7 @@ pub struct FileTransport {
 }
 
 /// Asynchronously writes the content and the envelope information to a file
-#[derive(Debug)]
+#[derive(Debug, Clone)]
 #[cfg_attr(feature = "serde", derive(serde::Serialize, serde::Deserialize))]
 #[cfg_attr(docsrs, doc(cfg(any(feature = "tokio1", feature = "async-std1"))))]
 #[cfg(any(feature = "async-std1", feature = "tokio1"))]

src/transport/mod.rs

@@ -32,7 +32,7 @@
 //! | [`smtp`]     | SMTP     | [`SmtpTransport`]     | [`AsyncSmtpTransport`]     | Uses the SMTP protocol to send emails to a relay server |
 //! | [`sendmail`] | Sendmail | [`SendmailTransport`] | [`AsyncSendmailTransport`] | Uses the `sendmail` command to send emails              |
 //! | [`file`]     | File     | [`FileTransport`]     | [`AsyncFileTransport`]     | Saves the email as an `.eml` file                       |
-//! | [`stub`]     | Debug    | [`StubTransport`]     | [`StubTransport`]          | Drops the email - Useful for debugging                  |
+//! | [`stub`]     | Debug    | [`StubTransport`]     | [`AsyncStubTransport`]     | Drops the email - Useful for debugging                  |
 //!
 //! ## Building an email
 //!
@@ -97,6 +97,7 @@
 //! [`FileTransport`]: crate::FileTransport
 //! [`AsyncFileTransport`]: crate::AsyncFileTransport
 //! [`StubTransport`]: crate::transport::stub::StubTransport
+//! [`AsyncStubTransport`]: crate::transport::stub::AsyncStubTransport
 
 #[cfg(any(feature = "async-std1", feature = "tokio1"))]
 use async_trait::async_trait;

src/transport/sendmail/error.rs

@@ -52,7 +52,7 @@ impl fmt::Debug for Error {
 
         builder.field("kind", &self.inner.kind);
 
-        if let Some(ref source) = self.inner.source {
+        if let Some(source) = &self.inner.source {
             builder.field("source", source);
         }
 
@@ -67,7 +67,7 @@ impl fmt::Display for Error {
             Kind::Client => f.write_str("internal client error")?,
         };
 
-        if let Some(ref e) = self.inner.source {
+        if let Some(e) = &self.inner.source {
             write!(f, ": {e}")?;
         }
 

src/transport/smtp/authentication.rs

@@ -98,11 +98,13 @@ impl Mechanism {
                 let decoded_challenge = challenge
                     .ok_or_else(|| error::client("This mechanism does expect a challenge"))?;
 
-                if ["User Name", "Username:", "Username"].contains(&decoded_challenge) {
+                if ["User Name", "Username:", "Username", "User Name\0"]
+                    .contains(&decoded_challenge)
+                {
                     return Ok(credentials.authentication_identity.clone());
                 }
 
-                if ["Password", "Password:"].contains(&decoded_challenge) {
+                if ["Password", "Password:", "Password\0"].contains(&decoded_challenge) {
                     return Ok(credentials.secret.clone());
                 }
 

src/transport/smtp/client/async_connection.rs

@@ -6,7 +6,7 @@ use futures_util::io::{AsyncBufReadExt, AsyncWriteExt, BufReader};
 use super::async_net::AsyncTokioStream;
 #[cfg(feature = "tracing")]
 use super::escape_crlf;
-use super::{AsyncNetworkStream, ClientCodec, TlsParameters};
+use super::{AsyncNetworkStream, ClientCodec, ConnectionState, TlsParameters};
 use crate::{
     transport::smtp::{
         authentication::{Credentials, Mechanism},
@@ -19,25 +19,11 @@ use crate::{
     Envelope,
 };
 
-macro_rules! try_smtp (
-    ($err: expr, $client: ident) => ({
-        match $err {
-            Ok(val) => val,
-            Err(err) => {
-                $client.abort().await;
-                return Err(From::from(err))
-            },
-        }
-    })
-);
-
 /// Structure that implements the SMTP client
 pub struct AsyncSmtpConnection {
     /// TCP stream between client and server
     /// Value is None before connection
     stream: BufReader<AsyncNetworkStream>,
-    /// Panic state
-    panic: bool,
     /// Information about the server
     server_info: ServerInfo,
 }
@@ -65,7 +51,7 @@ impl AsyncSmtpConnection {
     /// If `tls_parameters` is `Some`, then the connection will use Implicit TLS (sometimes
     /// referred to as `SMTPS`). See also [`AsyncSmtpConnection::starttls`].
     ///
-    /// If `local_addres` is `Some`, then the address provided shall be used to bind the
+    /// If `local_address` is `Some`, then the address provided shall be used to bind the
     /// connection to a specific local address using [`tokio1_crate::net::TcpSocket::bind`].
     ///
     /// Sends EHLO and parses server information
@@ -126,7 +112,6 @@ impl AsyncSmtpConnection {
         let stream = BufReader::new(stream);
         let mut conn = AsyncSmtpConnection {
             stream,
-            panic: false,
             server_info: ServerInfo::default(),
         };
         // TODO log
@@ -170,30 +155,26 @@ impl AsyncSmtpConnection {
             mail_options.push(MailParameter::Body(MailBodyParameter::EightBitMime));
         }
 
-        try_smtp!(
-            self.command(Mail::new(envelope.from().cloned(), mail_options))
-                .await,
-            self
-        );
+        self.command(Mail::new(envelope.from().cloned(), mail_options))
+            .await?;
 
         // Recipient
         for to_address in envelope.to() {
-            try_smtp!(
-                self.command(Rcpt::new(to_address.clone(), vec![])).await,
-                self
-            );
+            self.command(Rcpt::new(to_address.clone(), vec![])).await?;
         }
 
         // Data
-        try_smtp!(self.command(Data).await, self);
+        self.command(Data).await?;
 
         // Message content
-        let result = try_smtp!(self.message(email).await, self);
-        Ok(result)
+        self.message(email).await
     }
 
     pub fn has_broken(&self) -> bool {
-        self.panic
+        match self.stream.get_ref().state() {
+            ConnectionState::Ok => false,
+            ConnectionState::Broken | ConnectionState::Closed => true,
+        }
     }
 
     pub fn can_starttls(&self) -> bool {
@@ -208,18 +189,20 @@ impl AsyncSmtpConnection {
     /// [rfc8314]: https://www.rfc-editor.org/rfc/rfc8314
     #[allow(unused_variables)]
     pub async fn starttls(
-        &mut self,
+        mut self,
         tls_parameters: TlsParameters,
         hello_name: &ClientId,
-    ) -> Result<(), Error> {
+    ) -> Result<Self, Error> {
         if self.server_info.supports_feature(Extension::StartTls) {
-            try_smtp!(self.command(Starttls).await, self);
-            self.stream.get_mut().upgrade_tls(tls_parameters).await?;
+            self.command(Starttls).await?;
+            let stream = self.stream.into_inner();
+            let stream = stream.upgrade_tls(tls_parameters).await?;
+            self.stream = BufReader::new(stream);
             #[cfg(feature = "tracing")]
             tracing::debug!("connection encrypted");
             // Send EHLO again
-            try_smtp!(self.ehlo(hello_name).await, self);
-            Ok(())
+            self.ehlo(hello_name).await?;
+            Ok(self)
         } else {
             Err(error::client("STARTTLS is not supported on this server"))
         }
@@ -227,22 +210,24 @@ impl AsyncSmtpConnection {
 
     /// Send EHLO and update server info
     async fn ehlo(&mut self, hello_name: &ClientId) -> Result<(), Error> {
-        let ehlo_response = try_smtp!(self.command(Ehlo::new(hello_name.clone())).await, self);
-        self.server_info = try_smtp!(ServerInfo::from_response(&ehlo_response), self);
+        let ehlo_response = self.command(Ehlo::new(hello_name.clone())).await?;
+        self.server_info = ServerInfo::from_response(&ehlo_response)?;
         Ok(())
     }
 
     pub async fn quit(&mut self) -> Result<Response, Error> {
-        Ok(try_smtp!(self.command(Quit).await, self))
+        self.command(Quit).await
     }
 
     pub async fn abort(&mut self) {
-        // Only try to quit if we are not already broken
-        if !self.panic {
-            self.panic = true;
-            let _ = self.command(Quit).await;
+        match self.stream.get_ref().state() {
+            ConnectionState::Ok | ConnectionState::Broken => {
+                let _ = self.command(Quit).await;
+                let _ = self.stream.close().await;
+                self.stream.get_mut().set_state(ConnectionState::Closed);
+            }
+            ConnectionState::Closed => {}
         }
-        let _ = self.stream.close().await;
     }
 
     /// Sets the underlying stream
@@ -279,15 +264,13 @@ impl AsyncSmtpConnection {
 
         while challenges > 0 && response.has_code(334) {
             challenges -= 1;
-            response = try_smtp!(
-                self.command(Auth::new_from_response(
+            response = self
+                .command(Auth::new_from_response(
                     mechanism,
                     credentials.clone(),
                     &response,
                 )?)
-                .await,
-                self
-            );
+                .await?;
         }
 
         if challenges == 0 {
@@ -315,6 +298,9 @@ impl AsyncSmtpConnection {
 
     /// Writes a string to the server
     async fn write(&mut self, string: &[u8]) -> Result<(), Error> {
+        self.stream.get_ref().state().verify()?;
+        self.stream.get_mut().set_state(ConnectionState::Broken);
+
         self.stream
             .get_mut()
             .write_all(string)
@@ -326,6 +312,8 @@ impl AsyncSmtpConnection {
             .await
             .map_err(error::network)?;
 
+        self.stream.get_mut().set_state(ConnectionState::Ok);
+
         #[cfg(feature = "tracing")]
         tracing::debug!("Wrote: {}", escape_crlf(&String::from_utf8_lossy(string)));
         Ok(())
@@ -333,6 +321,9 @@ impl AsyncSmtpConnection {
 
     /// Gets the SMTP response
     pub async fn read_response(&mut self) -> Result<Response, Error> {
+        self.stream.get_ref().state().verify()?;
+        self.stream.get_mut().set_state(ConnectionState::Broken);
+
         let mut buffer = String::with_capacity(100);
 
         while self
@@ -346,6 +337,8 @@ impl AsyncSmtpConnection {
             tracing::debug!("<< {}", escape_crlf(&buffer));
             match parse_response(&buffer) {
                 Ok((_remaining, response)) => {
+                    self.stream.get_mut().set_state(ConnectionState::Ok);
+
                     return if response.is_positive() {
                         Ok(response)
                     } else {
@@ -353,7 +346,7 @@ impl AsyncSmtpConnection {
                             response.code(),
                             Some(response.message().collect()),
                         ))
-                    }
+                    };
                 }
                 Err(nom::Err::Failure(e)) => {
                     return Err(error::response(e.to_string()));

src/transport/smtp/client/async_net.rs

@@ -11,11 +11,12 @@ use async_native_tls::TlsStream as AsyncStd1TlsStream;
 #[cfg(feature = "async-std1")]
 use async_std::net::{TcpStream as AsyncStd1TcpStream, ToSocketAddrs as AsyncStd1ToSocketAddrs};
 use futures_io::{
-    AsyncRead as FuturesAsyncRead, AsyncWrite as FuturesAsyncWrite, Error as IoError, ErrorKind,
-    Result as IoResult,
+    AsyncRead as FuturesAsyncRead, AsyncWrite as FuturesAsyncWrite, Result as IoResult,
 };
 #[cfg(feature = "async-std1-rustls-tls")]
 use futures_rustls::client::TlsStream as AsyncStd1RustlsTlsStream;
+#[cfg(any(feature = "tokio1-rustls-tls", feature = "async-std1-rustls-tls"))]
+use rustls::pki_types::ServerName;
 #[cfg(feature = "tokio1-boring-tls")]
 use tokio1_boring::SslStream as Tokio1SslStream;
 #[cfg(feature = "tokio1")]
@@ -38,7 +39,7 @@ use tokio1_rustls::client::TlsStream as Tokio1RustlsTlsStream;
     feature = "async-std1-rustls-tls"
 ))]
 use super::InnerTlsParameters;
-use super::TlsParameters;
+use super::{ConnectionState, TlsParameters};
 #[cfg(feature = "tokio1")]
 use crate::transport::smtp::client::net::resolved_address_filter;
 use crate::transport::smtp::{error, Error};
@@ -47,6 +48,7 @@ use crate::transport::smtp::{error, Error};
 #[derive(Debug)]
 pub struct AsyncNetworkStream {
     inner: InnerAsyncNetworkStream,
+    state: ConnectionState,
 }
 
 #[cfg(feature = "tokio1")]
@@ -89,45 +91,43 @@ enum InnerAsyncNetworkStream {
     /// Encrypted Tokio 1.x TCP stream
     #[cfg(feature = "async-std1-rustls-tls")]
     AsyncStd1RustlsTls(AsyncStd1RustlsTlsStream<AsyncStd1TcpStream>),
-    /// Can't be built
-    None,
 }
 
 impl AsyncNetworkStream {
     fn new(inner: InnerAsyncNetworkStream) -> Self {
-        if let InnerAsyncNetworkStream::None = inner {
-            debug_assert!(false, "InnerAsyncNetworkStream::None must never be built");
+        AsyncNetworkStream {
+            inner,
+            state: ConnectionState::Ok,
         }
+    }
 
-        AsyncNetworkStream { inner }
+    pub(super) fn state(&self) -> ConnectionState {
+        self.state
+    }
+
+    pub(super) fn set_state(&mut self, state: ConnectionState) {
+        self.state = state;
     }
 
     /// Returns peer's address
     pub fn peer_addr(&self) -> IoResult<SocketAddr> {
-        match self.inner {
+        match &self.inner {
             #[cfg(feature = "tokio1")]
-            InnerAsyncNetworkStream::Tokio1Tcp(ref s) => s.peer_addr(),
+            InnerAsyncNetworkStream::Tokio1Tcp(s) => s.peer_addr(),
             #[cfg(feature = "tokio1-native-tls")]
-            InnerAsyncNetworkStream::Tokio1NativeTls(ref s) => {
+            InnerAsyncNetworkStream::Tokio1NativeTls(s) => {
                 s.get_ref().get_ref().get_ref().peer_addr()
             }
             #[cfg(feature = "tokio1-rustls-tls")]
-            InnerAsyncNetworkStream::Tokio1RustlsTls(ref s) => s.get_ref().0.peer_addr(),
+            InnerAsyncNetworkStream::Tokio1RustlsTls(s) => s.get_ref().0.peer_addr(),
             #[cfg(feature = "tokio1-boring-tls")]
-            InnerAsyncNetworkStream::Tokio1BoringTls(ref s) => s.get_ref().peer_addr(),
+            InnerAsyncNetworkStream::Tokio1BoringTls(s) => s.get_ref().peer_addr(),
             #[cfg(feature = "async-std1")]
-            InnerAsyncNetworkStream::AsyncStd1Tcp(ref s) => s.peer_addr(),
+            InnerAsyncNetworkStream::AsyncStd1Tcp(s) => s.peer_addr(),
             #[cfg(feature = "async-std1-native-tls")]
-            InnerAsyncNetworkStream::AsyncStd1NativeTls(ref s) => s.get_ref().peer_addr(),
+            InnerAsyncNetworkStream::AsyncStd1NativeTls(s) => s.get_ref().peer_addr(),
             #[cfg(feature = "async-std1-rustls-tls")]
-            InnerAsyncNetworkStream::AsyncStd1RustlsTls(ref s) => s.get_ref().0.peer_addr(),
-            InnerAsyncNetworkStream::None => {
-                debug_assert!(false, "InnerAsyncNetworkStream::None must never be built");
-                Err(IoError::new(
-                    ErrorKind::Other,
-                    "InnerAsyncNetworkStream::None must never be built",
-                ))
-            }
+            InnerAsyncNetworkStream::AsyncStd1RustlsTls(s) => s.get_ref().0.peer_addr(),
         }
     }
 
@@ -197,7 +197,7 @@ impl AsyncNetworkStream {
         let mut stream =
             AsyncNetworkStream::new(InnerAsyncNetworkStream::Tokio1Tcp(Box::new(tcp_stream)));
         if let Some(tls_parameters) = tls_parameters {
-            stream.upgrade_tls(tls_parameters).await?;
+            stream = stream.upgrade_tls(tls_parameters).await?;
         }
         Ok(stream)
     }
@@ -248,13 +248,13 @@ impl AsyncNetworkStream {
 
         let mut stream = AsyncNetworkStream::new(InnerAsyncNetworkStream::AsyncStd1Tcp(tcp_stream));
         if let Some(tls_parameters) = tls_parameters {
-            stream.upgrade_tls(tls_parameters).await?;
+            stream = stream.upgrade_tls(tls_parameters).await?;
         }
         Ok(stream)
     }
 
-    pub async fn upgrade_tls(&mut self, tls_parameters: TlsParameters) -> Result<(), Error> {
-        match &self.inner {
+    pub async fn upgrade_tls(self, tls_parameters: TlsParameters) -> Result<Self, Error> {
+        match self.inner {
             #[cfg(all(
                 feature = "tokio1",
                 not(any(
@@ -273,18 +273,14 @@ impl AsyncNetworkStream {
                 feature = "tokio1-rustls-tls",
                 feature = "tokio1-boring-tls"
             ))]
-            InnerAsyncNetworkStream::Tokio1Tcp(_) => {
-                // get owned TcpStream
-                let tcp_stream = mem::replace(&mut self.inner, InnerAsyncNetworkStream::None);
-                let tcp_stream = match tcp_stream {
-                    InnerAsyncNetworkStream::Tokio1Tcp(tcp_stream) => tcp_stream,
-                    _ => unreachable!(),
-                };
-
-                self.inner = Self::upgrade_tokio1_tls(tcp_stream, tls_parameters)
+            InnerAsyncNetworkStream::Tokio1Tcp(tcp_stream) => {
+                let inner = Self::upgrade_tokio1_tls(tcp_stream, tls_parameters)
                     .await
                     .map_err(error::connection)?;
-                Ok(())
+                Ok(Self {
+                    inner,
+                    state: ConnectionState::Ok,
+                })
             }
             #[cfg(all(
                 feature = "async-std1",
@@ -296,20 +292,16 @@ impl AsyncNetworkStream {
             }
 
             #[cfg(any(feature = "async-std1-native-tls", feature = "async-std1-rustls-tls"))]
-            InnerAsyncNetworkStream::AsyncStd1Tcp(_) => {
-                // get owned TcpStream
-                let tcp_stream = mem::replace(&mut self.inner, InnerAsyncNetworkStream::None);
-                let tcp_stream = match tcp_stream {
-                    InnerAsyncNetworkStream::AsyncStd1Tcp(tcp_stream) => tcp_stream,
-                    _ => unreachable!(),
-                };
-
-                self.inner = Self::upgrade_asyncstd1_tls(tcp_stream, tls_parameters)
+            InnerAsyncNetworkStream::AsyncStd1Tcp(tcp_stream) => {
+                let inner = Self::upgrade_asyncstd1_tls(tcp_stream, tls_parameters)
                     .await
                     .map_err(error::connection)?;
-                Ok(())
+                Ok(Self {
+                    inner,
+                    state: ConnectionState::Ok,
+                })
             }
-            _ => Ok(()),
+            _ => Ok(self),
         }
     }
 
@@ -350,7 +342,6 @@ impl AsyncNetworkStream {
 
                 #[cfg(feature = "tokio1-rustls-tls")]
                 return {
-                    use rustls::ServerName;
                     use tokio1_rustls::TlsConnector;
 
                     let domain = ServerName::try_from(domain.as_str())
@@ -358,7 +349,7 @@ impl AsyncNetworkStream {
 
                     let connector = TlsConnector::from(config);
                     let stream = connector
-                        .connect(domain, tcp_stream)
+                        .connect(domain.to_owned(), tcp_stream)
                         .await
                         .map_err(error::connection)?;
                     Ok(InnerAsyncNetworkStream::Tokio1RustlsTls(stream))
@@ -424,14 +415,13 @@ impl AsyncNetworkStream {
                 #[cfg(feature = "async-std1-rustls-tls")]
                 return {
                     use futures_rustls::TlsConnector;
-                    use rustls::ServerName;
 
                     let domain = ServerName::try_from(domain.as_str())
                         .map_err(|_| error::connection("domain isn't a valid DNS name"))?;
 
                     let connector = TlsConnector::from(config);
                     let stream = connector
-                        .connect(domain, tcp_stream)
+                        .connect(domain.to_owned(), tcp_stream)
                         .await
                         .map_err(error::connection)?;
                     Ok(InnerAsyncNetworkStream::AsyncStd1RustlsTls(stream))
@@ -445,7 +435,7 @@ impl AsyncNetworkStream {
     }
 
     pub fn is_encrypted(&self) -> bool {
-        match self.inner {
+        match &self.inner {
             #[cfg(feature = "tokio1")]
             InnerAsyncNetworkStream::Tokio1Tcp(_) => false,
             #[cfg(feature = "tokio1-native-tls")]
@@ -460,7 +450,6 @@ impl AsyncNetworkStream {
             InnerAsyncNetworkStream::AsyncStd1NativeTls(_) => true,
             #[cfg(feature = "async-std1-rustls-tls")]
             InnerAsyncNetworkStream::AsyncStd1RustlsTls(_) => true,
-            InnerAsyncNetworkStream::None => false,
         }
     }
 
@@ -486,8 +475,7 @@ impl AsyncNetworkStream {
                 .unwrap()
                 .first()
                 .unwrap()
-                .clone()
-                .0),
+                .to_vec()),
             #[cfg(feature = "tokio1-boring-tls")]
             InnerAsyncNetworkStream::Tokio1BoringTls(stream) => Ok(stream
                 .ssl()
@@ -509,9 +497,7 @@ impl AsyncNetworkStream {
                 .unwrap()
                 .first()
                 .unwrap()
-                .clone()
-                .0),
-            InnerAsyncNetworkStream::None => panic!("InnerNetworkStream::None must never be built"),
+                .to_vec()),
         }
     }
 }
@@ -522,9 +508,9 @@ impl FuturesAsyncRead for AsyncNetworkStream {
         cx: &mut Context<'_>,
         buf: &mut [u8],
     ) -> Poll<IoResult<usize>> {
-        match self.inner {
+        match &mut self.inner {
             #[cfg(feature = "tokio1")]
-            InnerAsyncNetworkStream::Tokio1Tcp(ref mut s) => {
+            InnerAsyncNetworkStream::Tokio1Tcp(s) => {
                 let mut b = Tokio1ReadBuf::new(buf);
                 match Pin::new(s).poll_read(cx, &mut b) {
                     Poll::Ready(Ok(())) => Poll::Ready(Ok(b.filled().len())),
@@ -533,7 +519,7 @@ impl FuturesAsyncRead for AsyncNetworkStream {
                 }
             }
             #[cfg(feature = "tokio1-native-tls")]
-            InnerAsyncNetworkStream::Tokio1NativeTls(ref mut s) => {
+            InnerAsyncNetworkStream::Tokio1NativeTls(s) => {
                 let mut b = Tokio1ReadBuf::new(buf);
                 match Pin::new(s).poll_read(cx, &mut b) {
                     Poll::Ready(Ok(())) => Poll::Ready(Ok(b.filled().len())),
@@ -542,7 +528,7 @@ impl FuturesAsyncRead for AsyncNetworkStream {
                 }
             }
             #[cfg(feature = "tokio1-rustls-tls")]
-            InnerAsyncNetworkStream::Tokio1RustlsTls(ref mut s) => {
+            InnerAsyncNetworkStream::Tokio1RustlsTls(s) => {
                 let mut b = Tokio1ReadBuf::new(buf);
                 match Pin::new(s).poll_read(cx, &mut b) {
                     Poll::Ready(Ok(())) => Poll::Ready(Ok(b.filled().len())),
@@ -551,7 +537,7 @@ impl FuturesAsyncRead for AsyncNetworkStream {
                 }
             }
             #[cfg(feature = "tokio1-boring-tls")]
-            InnerAsyncNetworkStream::Tokio1BoringTls(ref mut s) => {
+            InnerAsyncNetworkStream::Tokio1BoringTls(s) => {
                 let mut b = Tokio1ReadBuf::new(buf);
                 match Pin::new(s).poll_read(cx, &mut b) {
                     Poll::Ready(Ok(())) => Poll::Ready(Ok(b.filled().len())),
@@ -560,19 +546,11 @@ impl FuturesAsyncRead for AsyncNetworkStream {
                 }
             }
             #[cfg(feature = "async-std1")]
-            InnerAsyncNetworkStream::AsyncStd1Tcp(ref mut s) => Pin::new(s).poll_read(cx, buf),
+            InnerAsyncNetworkStream::AsyncStd1Tcp(s) => Pin::new(s).poll_read(cx, buf),
             #[cfg(feature = "async-std1-native-tls")]
-            InnerAsyncNetworkStream::AsyncStd1NativeTls(ref mut s) => {
-                Pin::new(s).poll_read(cx, buf)
-            }
+            InnerAsyncNetworkStream::AsyncStd1NativeTls(s) => Pin::new(s).poll_read(cx, buf),
             #[cfg(feature = "async-std1-rustls-tls")]
-            InnerAsyncNetworkStream::AsyncStd1RustlsTls(ref mut s) => {
-                Pin::new(s).poll_read(cx, buf)
-            }
-            InnerAsyncNetworkStream::None => {
-                debug_assert!(false, "InnerAsyncNetworkStream::None must never be built");
-                Poll::Ready(Ok(0))
-            }
+            InnerAsyncNetworkStream::AsyncStd1RustlsTls(s) => Pin::new(s).poll_read(cx, buf),
         }
     }
 }
@@ -583,75 +561,61 @@ impl FuturesAsyncWrite for AsyncNetworkStream {
         cx: &mut Context<'_>,
         buf: &[u8],
     ) -> Poll<IoResult<usize>> {
-        match self.inner {
+        match &mut self.inner {
             #[cfg(feature = "tokio1")]
-            InnerAsyncNetworkStream::Tokio1Tcp(ref mut s) => Pin::new(s).poll_write(cx, buf),
+            InnerAsyncNetworkStream::Tokio1Tcp(s) => Pin::new(s).poll_write(cx, buf),
             #[cfg(feature = "tokio1-native-tls")]
-            InnerAsyncNetworkStream::Tokio1NativeTls(ref mut s) => Pin::new(s).poll_write(cx, buf),
+            InnerAsyncNetworkStream::Tokio1NativeTls(s) => Pin::new(s).poll_write(cx, buf),
             #[cfg(feature = "tokio1-rustls-tls")]
-            InnerAsyncNetworkStream::Tokio1RustlsTls(ref mut s) => Pin::new(s).poll_write(cx, buf),
+            InnerAsyncNetworkStream::Tokio1RustlsTls(s) => Pin::new(s).poll_write(cx, buf),
             #[cfg(feature = "tokio1-boring-tls")]
-            InnerAsyncNetworkStream::Tokio1BoringTls(ref mut s) => Pin::new(s).poll_write(cx, buf),
+            InnerAsyncNetworkStream::Tokio1BoringTls(s) => Pin::new(s).poll_write(cx, buf),
             #[cfg(feature = "async-std1")]
-            InnerAsyncNetworkStream::AsyncStd1Tcp(ref mut s) => Pin::new(s).poll_write(cx, buf),
+            InnerAsyncNetworkStream::AsyncStd1Tcp(s) => Pin::new(s).poll_write(cx, buf),
             #[cfg(feature = "async-std1-native-tls")]
-            InnerAsyncNetworkStream::AsyncStd1NativeTls(ref mut s) => {
-                Pin::new(s).poll_write(cx, buf)
-            }
+            InnerAsyncNetworkStream::AsyncStd1NativeTls(s) => Pin::new(s).poll_write(cx, buf),
             #[cfg(feature = "async-std1-rustls-tls")]
-            InnerAsyncNetworkStream::AsyncStd1RustlsTls(ref mut s) => {
-                Pin::new(s).poll_write(cx, buf)
-            }
-            InnerAsyncNetworkStream::None => {
-                debug_assert!(false, "InnerAsyncNetworkStream::None must never be built");
-                Poll::Ready(Ok(0))
-            }
+            InnerAsyncNetworkStream::AsyncStd1RustlsTls(s) => Pin::new(s).poll_write(cx, buf),
         }
     }
 
     fn poll_flush(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<IoResult<()>> {
-        match self.inner {
+        match &mut self.inner {
             #[cfg(feature = "tokio1")]
-            InnerAsyncNetworkStream::Tokio1Tcp(ref mut s) => Pin::new(s).poll_flush(cx),
+            InnerAsyncNetworkStream::Tokio1Tcp(s) => Pin::new(s).poll_flush(cx),
             #[cfg(feature = "tokio1-native-tls")]
-            InnerAsyncNetworkStream::Tokio1NativeTls(ref mut s) => Pin::new(s).poll_flush(cx),
+            InnerAsyncNetworkStream::Tokio1NativeTls(s) => Pin::new(s).poll_flush(cx),
             #[cfg(feature = "tokio1-rustls-tls")]
-            InnerAsyncNetworkStream::Tokio1RustlsTls(ref mut s) => Pin::new(s).poll_flush(cx),
+            InnerAsyncNetworkStream::Tokio1RustlsTls(s) => Pin::new(s).poll_flush(cx),
             #[cfg(feature = "tokio1-boring-tls")]
-            InnerAsyncNetworkStream::Tokio1BoringTls(ref mut s) => Pin::new(s).poll_flush(cx),
+            InnerAsyncNetworkStream::Tokio1BoringTls(s) => Pin::new(s).poll_flush(cx),
             #[cfg(feature = "async-std1")]
-            InnerAsyncNetworkStream::AsyncStd1Tcp(ref mut s) => Pin::new(s).poll_flush(cx),
+            InnerAsyncNetworkStream::AsyncStd1Tcp(s) => Pin::new(s).poll_flush(cx),
             #[cfg(feature = "async-std1-native-tls")]
-            InnerAsyncNetworkStream::AsyncStd1NativeTls(ref mut s) => Pin::new(s).poll_flush(cx),
+            InnerAsyncNetworkStream::AsyncStd1NativeTls(s) => Pin::new(s).poll_flush(cx),
             #[cfg(feature = "async-std1-rustls-tls")]
-            InnerAsyncNetworkStream::AsyncStd1RustlsTls(ref mut s) => Pin::new(s).poll_flush(cx),
-            InnerAsyncNetworkStream::None => {
-                debug_assert!(false, "InnerAsyncNetworkStream::None must never be built");
-                Poll::Ready(Ok(()))
-            }
+            InnerAsyncNetworkStream::AsyncStd1RustlsTls(s) => Pin::new(s).poll_flush(cx),
         }
     }
 
     fn poll_close(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<IoResult<()>> {
-        match self.inner {
+        self.state = ConnectionState::Closed;
+
+        match &mut self.inner {
             #[cfg(feature = "tokio1")]
-            InnerAsyncNetworkStream::Tokio1Tcp(ref mut s) => Pin::new(s).poll_shutdown(cx),
+            InnerAsyncNetworkStream::Tokio1Tcp(s) => Pin::new(s).poll_shutdown(cx),
             #[cfg(feature = "tokio1-native-tls")]
-            InnerAsyncNetworkStream::Tokio1NativeTls(ref mut s) => Pin::new(s).poll_shutdown(cx),
+            InnerAsyncNetworkStream::Tokio1NativeTls(s) => Pin::new(s).poll_shutdown(cx),
             #[cfg(feature = "tokio1-rustls-tls")]
-            InnerAsyncNetworkStream::Tokio1RustlsTls(ref mut s) => Pin::new(s).poll_shutdown(cx),
+            InnerAsyncNetworkStream::Tokio1RustlsTls(s) => Pin::new(s).poll_shutdown(cx),
             #[cfg(feature = "tokio1-boring-tls")]
-            InnerAsyncNetworkStream::Tokio1BoringTls(ref mut s) => Pin::new(s).poll_shutdown(cx),
+            InnerAsyncNetworkStream::Tokio1BoringTls(s) => Pin::new(s).poll_shutdown(cx),
             #[cfg(feature = "async-std1")]
-            InnerAsyncNetworkStream::AsyncStd1Tcp(ref mut s) => Pin::new(s).poll_close(cx),
+            InnerAsyncNetworkStream::AsyncStd1Tcp(s) => Pin::new(s).poll_close(cx),
             #[cfg(feature = "async-std1-native-tls")]
-            InnerAsyncNetworkStream::AsyncStd1NativeTls(ref mut s) => Pin::new(s).poll_close(cx),
+            InnerAsyncNetworkStream::AsyncStd1NativeTls(s) => Pin::new(s).poll_close(cx),
             #[cfg(feature = "async-std1-rustls-tls")]
-            InnerAsyncNetworkStream::AsyncStd1RustlsTls(ref mut s) => Pin::new(s).poll_close(cx),
-            InnerAsyncNetworkStream::None => {
-                debug_assert!(false, "InnerAsyncNetworkStream::None must never be built");
-                Poll::Ready(Ok(()))
-            }
+            InnerAsyncNetworkStream::AsyncStd1RustlsTls(s) => Pin::new(s).poll_close(cx),
         }
     }
 }

src/transport/smtp/client/connection.rs

@@ -7,7 +7,7 @@ use std::{
 
 #[cfg(feature = "tracing")]
 use super::escape_crlf;
-use super::{ClientCodec, NetworkStream, TlsParameters};
+use super::{ClientCodec, ConnectionState, NetworkStream, TlsParameters};
 use crate::{
     address::Envelope,
     transport::smtp::{
@@ -20,25 +20,11 @@ use crate::{
     },
 };
 
-macro_rules! try_smtp (
-    ($err: expr, $client: ident) => ({
-        match $err {
-            Ok(val) => val,
-            Err(err) => {
-                $client.abort();
-                return Err(From::from(err))
-            },
-        }
-    })
-);
-
 /// Structure that implements the SMTP client
 pub struct SmtpConnection {
     /// TCP stream between client and server
     /// Value is None before connection
     stream: BufReader<NetworkStream>,
-    /// Panic state
-    panic: bool,
     /// Information about the server
     server_info: ServerInfo,
 }
@@ -65,7 +51,6 @@ impl SmtpConnection {
         let stream = BufReader::new(stream);
         let mut conn = SmtpConnection {
             stream,
-            panic: false,
             server_info: ServerInfo::default(),
         };
         conn.set_timeout(timeout).map_err(error::network)?;
@@ -110,26 +95,25 @@ impl SmtpConnection {
             mail_options.push(MailParameter::Body(MailBodyParameter::EightBitMime));
         }
 
-        try_smtp!(
-            self.command(Mail::new(envelope.from().cloned(), mail_options)),
-            self
-        );
+        self.command(Mail::new(envelope.from().cloned(), mail_options))?;
 
         // Recipient
         for to_address in envelope.to() {
-            try_smtp!(self.command(Rcpt::new(to_address.clone(), vec![])), self);
+            self.command(Rcpt::new(to_address.clone(), vec![]))?;
         }
 
         // Data
-        try_smtp!(self.command(Data), self);
+        self.command(Data)?;
 
         // Message content
-        let result = try_smtp!(self.message(email), self);
-        Ok(result)
+        self.message(email)
     }
 
     pub fn has_broken(&self) -> bool {
-        self.panic
+        match self.stream.get_ref().state() {
+            ConnectionState::Ok => false,
+            ConnectionState::Broken | ConnectionState::Closed => true,
+        }
     }
 
     pub fn can_starttls(&self) -> bool {
@@ -138,20 +122,22 @@ impl SmtpConnection {
 
     #[allow(unused_variables)]
     pub fn starttls(
-        &mut self,
+        mut self,
         tls_parameters: &TlsParameters,
         hello_name: &ClientId,
-    ) -> Result<(), Error> {
+    ) -> Result<Self, Error> {
         if self.server_info.supports_feature(Extension::StartTls) {
             #[cfg(any(feature = "native-tls", feature = "rustls-tls", feature = "boring-tls"))]
             {
-                try_smtp!(self.command(Starttls), self);
-                self.stream.get_mut().upgrade_tls(tls_parameters)?;
+                self.command(Starttls)?;
+                let stream = self.stream.into_inner();
+                let stream = stream.upgrade_tls(tls_parameters)?;
+                self.stream = BufReader::new(stream);
                 #[cfg(feature = "tracing")]
                 tracing::debug!("connection encrypted");
                 // Send EHLO again
-                try_smtp!(self.ehlo(hello_name), self);
-                Ok(())
+                self.ehlo(hello_name)?;
+                Ok(self)
             }
             #[cfg(not(any(
                 feature = "native-tls",
@@ -168,22 +154,24 @@ impl SmtpConnection {
 
     /// Send EHLO and update server info
     fn ehlo(&mut self, hello_name: &ClientId) -> Result<(), Error> {
-        let ehlo_response = try_smtp!(self.command(Ehlo::new(hello_name.clone())), self);
-        self.server_info = try_smtp!(ServerInfo::from_response(&ehlo_response), self);
+        let ehlo_response = self.command(Ehlo::new(hello_name.clone()))?;
+        self.server_info = ServerInfo::from_response(&ehlo_response)?;
         Ok(())
     }
 
     pub fn quit(&mut self) -> Result<Response, Error> {
-        Ok(try_smtp!(self.command(Quit), self))
+        self.command(Quit)
     }
 
     pub fn abort(&mut self) {
-        // Only try to quit if we are not already broken
-        if !self.panic {
-            self.panic = true;
-            let _ = self.command(Quit);
+        match self.stream.get_ref().state() {
+            ConnectionState::Ok | ConnectionState::Broken => {
+                let _ = self.command(Quit);
+                let _ = self.stream.get_mut().shutdown(std::net::Shutdown::Both);
+                self.stream.get_mut().set_state(ConnectionState::Closed);
+            }
+            ConnectionState::Closed => {}
         }
-        let _ = self.stream.get_mut().shutdown(std::net::Shutdown::Both);
     }
 
     /// Sets the underlying stream
@@ -224,14 +212,11 @@ impl SmtpConnection {
 
         while challenges > 0 && response.has_code(334) {
             challenges -= 1;
-            response = try_smtp!(
-                self.command(Auth::new_from_response(
-                    mechanism,
-                    credentials.clone(),
-                    &response,
-                )?),
-                self
-            );
+            response = self.command(Auth::new_from_response(
+                mechanism,
+                credentials.clone(),
+                &response,
+            )?)?;
         }
 
         if challenges == 0 {
@@ -260,12 +245,17 @@ impl SmtpConnection {
 
     /// Writes a string to the server
     fn write(&mut self, string: &[u8]) -> Result<(), Error> {
+        self.stream.get_ref().state().verify()?;
+        self.stream.get_mut().set_state(ConnectionState::Broken);
+
         self.stream
             .get_mut()
             .write_all(string)
             .map_err(error::network)?;
         self.stream.get_mut().flush().map_err(error::network)?;
 
+        self.stream.get_mut().set_state(ConnectionState::Ok);
+
         #[cfg(feature = "tracing")]
         tracing::debug!("Wrote: {}", escape_crlf(&String::from_utf8_lossy(string)));
         Ok(())
@@ -273,6 +263,9 @@ impl SmtpConnection {
 
     /// Gets the SMTP response
     pub fn read_response(&mut self) -> Result<Response, Error> {
+        self.stream.get_ref().state().verify()?;
+        self.stream.get_mut().set_state(ConnectionState::Broken);
+
         let mut buffer = String::with_capacity(100);
 
         while self.stream.read_line(&mut buffer).map_err(error::network)? > 0 {
@@ -280,6 +273,8 @@ impl SmtpConnection {
             tracing::debug!("<< {}", escape_crlf(&buffer));
             match parse_response(&buffer) {
                 Ok((_remaining, response)) => {
+                    self.stream.get_mut().set_state(ConnectionState::Ok);
+
                     return if response.is_positive() {
                         Ok(response)
                     } else {

src/transport/smtp/client/mod.rs

@@ -40,6 +40,7 @@ pub use self::{
     connection::SmtpConnection,
     tls::{Certificate, CertificateStore, Tls, TlsParameters, TlsParametersBuilder},
 };
+use super::{error, Error};
 
 #[cfg(any(feature = "tokio1", feature = "async-std1"))]
 mod async_connection;
@@ -49,6 +50,23 @@ mod connection;
 mod net;
 mod tls;
 
+#[derive(Debug, Copy, Clone)]
+enum ConnectionState {
+    Ok,
+    Broken,
+    Closed,
+}
+
+impl ConnectionState {
+    fn verify(&mut self) -> Result<(), Error> {
+        match self {
+            Self::Ok => Ok(()),
+            Self::Broken => Err(error::connection("connection broken")),
+            Self::Closed => Err(error::connection("connection closed")),
+        }
+    }
+}
+
 /// The codec used for transparency
 #[derive(Debug)]
 struct ClientCodec {

src/transport/smtp/client/net.rs

@@ -2,8 +2,7 @@
 use std::sync::Arc;
 use std::{
     io::{self, Read, Write},
-    mem,
-    net::{IpAddr, Ipv4Addr, Shutdown, SocketAddr, SocketAddrV4, TcpStream, ToSocketAddrs},
+    net::{IpAddr, Shutdown, SocketAddr, TcpStream, ToSocketAddrs},
     time::Duration,
 };
 
@@ -12,17 +11,18 @@ use boring::ssl::SslStream;
 #[cfg(feature = "native-tls")]
 use native_tls::TlsStream;
 #[cfg(feature = "rustls-tls")]
-use rustls::{ClientConnection, ServerName, StreamOwned};
+use rustls::{pki_types::ServerName, ClientConnection, StreamOwned};
 use socket2::{Domain, Protocol, Type};
 
 #[cfg(any(feature = "native-tls", feature = "rustls-tls", feature = "boring-tls"))]
 use super::InnerTlsParameters;
-use super::TlsParameters;
+use super::{ConnectionState, TlsParameters};
 use crate::transport::smtp::{error, Error};
 
 /// A network stream
 pub struct NetworkStream {
     inner: InnerNetworkStream,
+    state: ConnectionState,
 }
 
 /// Represents the different types of underlying network streams
@@ -40,53 +40,49 @@ enum InnerNetworkStream {
     RustlsTls(StreamOwned<ClientConnection, TcpStream>),
     #[cfg(feature = "boring-tls")]
     BoringTls(SslStream<TcpStream>),
-    /// Can't be built
-    None,
 }
 
 impl NetworkStream {
     fn new(inner: InnerNetworkStream) -> Self {
-        if let InnerNetworkStream::None = inner {
-            debug_assert!(false, "InnerNetworkStream::None must never be built");
+        NetworkStream {
+            inner,
+            state: ConnectionState::Ok,
         }
+    }
 
-        NetworkStream { inner }
+    pub(super) fn state(&self) -> ConnectionState {
+        self.state
+    }
+
+    pub(super) fn set_state(&mut self, state: ConnectionState) {
+        self.state = state;
     }
 
     /// Returns peer's address
     pub fn peer_addr(&self) -> io::Result<SocketAddr> {
-        match self.inner {
-            InnerNetworkStream::Tcp(ref s) => s.peer_addr(),
+        match &self.inner {
+            InnerNetworkStream::Tcp(s) => s.peer_addr(),
             #[cfg(feature = "native-tls")]
-            InnerNetworkStream::NativeTls(ref s) => s.get_ref().peer_addr(),
+            InnerNetworkStream::NativeTls(s) => s.get_ref().peer_addr(),
             #[cfg(feature = "rustls-tls")]
-            InnerNetworkStream::RustlsTls(ref s) => s.get_ref().peer_addr(),
+            InnerNetworkStream::RustlsTls(s) => s.get_ref().peer_addr(),
             #[cfg(feature = "boring-tls")]
-            InnerNetworkStream::BoringTls(ref s) => s.get_ref().peer_addr(),
-            InnerNetworkStream::None => {
-                debug_assert!(false, "InnerNetworkStream::None must never be built");
-                Ok(SocketAddr::V4(SocketAddrV4::new(
-                    Ipv4Addr::new(127, 0, 0, 1),
-                    80,
-                )))
-            }
+            InnerNetworkStream::BoringTls(s) => s.get_ref().peer_addr(),
         }
     }
 
     /// Shutdowns the connection
-    pub fn shutdown(&self, how: Shutdown) -> io::Result<()> {
-        match self.inner {
-            InnerNetworkStream::Tcp(ref s) => s.shutdown(how),
+    pub fn shutdown(&mut self, how: Shutdown) -> io::Result<()> {
+        self.state = ConnectionState::Closed;
+
+        match &self.inner {
+            InnerNetworkStream::Tcp(s) => s.shutdown(how),
             #[cfg(feature = "native-tls")]
-            InnerNetworkStream::NativeTls(ref s) => s.get_ref().shutdown(how),
+            InnerNetworkStream::NativeTls(s) => s.get_ref().shutdown(how),
             #[cfg(feature = "rustls-tls")]
-            InnerNetworkStream::RustlsTls(ref s) => s.get_ref().shutdown(how),
+            InnerNetworkStream::RustlsTls(s) => s.get_ref().shutdown(how),
             #[cfg(feature = "boring-tls")]
-            InnerNetworkStream::BoringTls(ref s) => s.get_ref().shutdown(how),
-            InnerNetworkStream::None => {
-                debug_assert!(false, "InnerNetworkStream::None must never be built");
-                Ok(())
-            }
+            InnerNetworkStream::BoringTls(s) => s.get_ref().shutdown(how),
         }
     }
 
@@ -139,13 +135,13 @@ impl NetworkStream {
         let tcp_stream = try_connect(server, timeout, local_addr)?;
         let mut stream = NetworkStream::new(InnerNetworkStream::Tcp(tcp_stream));
         if let Some(tls_parameters) = tls_parameters {
-            stream.upgrade_tls(tls_parameters)?;
+            stream = stream.upgrade_tls(tls_parameters)?;
         }
         Ok(stream)
     }
 
-    pub fn upgrade_tls(&mut self, tls_parameters: &TlsParameters) -> Result<(), Error> {
-        match &self.inner {
+    pub fn upgrade_tls(self, tls_parameters: &TlsParameters) -> Result<Self, Error> {
+        match self.inner {
             #[cfg(not(any(
                 feature = "native-tls",
                 feature = "rustls-tls",
@@ -157,18 +153,14 @@ impl NetworkStream {
             }
 
             #[cfg(any(feature = "native-tls", feature = "rustls-tls", feature = "boring-tls"))]
-            InnerNetworkStream::Tcp(_) => {
-                // get owned TcpStream
-                let tcp_stream = mem::replace(&mut self.inner, InnerNetworkStream::None);
-                let tcp_stream = match tcp_stream {
-                    InnerNetworkStream::Tcp(tcp_stream) => tcp_stream,
-                    _ => unreachable!(),
-                };
-
-                self.inner = Self::upgrade_tls_impl(tcp_stream, tls_parameters)?;
-                Ok(())
+            InnerNetworkStream::Tcp(tcp_stream) => {
+                let inner = Self::upgrade_tls_impl(tcp_stream, tls_parameters)?;
+                Ok(Self {
+                    inner,
+                    state: ConnectionState::Ok,
+                })
             }
-            _ => Ok(()),
+            _ => Ok(self),
         }
     }
 
@@ -189,7 +181,7 @@ impl NetworkStream {
             InnerTlsParameters::RustlsTls(connector) => {
                 let domain = ServerName::try_from(tls_parameters.domain())
                     .map_err(|_| error::connection("domain isn't a valid DNS name"))?;
-                let connection = ClientConnection::new(Arc::clone(connector), domain)
+                let connection = ClientConnection::new(Arc::clone(connector), domain.to_owned())
                     .map_err(error::connection)?;
                 let stream = StreamOwned::new(connection, tcp_stream);
                 InnerNetworkStream::RustlsTls(stream)
@@ -208,7 +200,7 @@ impl NetworkStream {
     }
 
     pub fn is_encrypted(&self) -> bool {
-        match self.inner {
+        match &self.inner {
             InnerNetworkStream::Tcp(_) => false,
             #[cfg(feature = "native-tls")]
             InnerNetworkStream::NativeTls(_) => true,
@@ -216,10 +208,6 @@ impl NetworkStream {
             InnerNetworkStream::RustlsTls(_) => true,
             #[cfg(feature = "boring-tls")]
             InnerNetworkStream::BoringTls(_) => true,
-            InnerNetworkStream::None => {
-                debug_assert!(false, "InnerNetworkStream::None must never be built");
-                false
-            }
         }
     }
 
@@ -241,8 +229,7 @@ impl NetworkStream {
                 .unwrap()
                 .first()
                 .unwrap()
-                .clone()
-                .0),
+                .to_vec()),
             #[cfg(feature = "boring-tls")]
             InnerNetworkStream::BoringTls(stream) => Ok(stream
                 .ssl()
@@ -250,105 +237,72 @@ impl NetworkStream {
                 .unwrap()
                 .to_der()
                 .map_err(error::tls)?),
-            InnerNetworkStream::None => panic!("InnerNetworkStream::None must never be built"),
         }
     }
 
     pub fn set_read_timeout(&mut self, duration: Option<Duration>) -> io::Result<()> {
-        match self.inner {
-            InnerNetworkStream::Tcp(ref mut stream) => stream.set_read_timeout(duration),
+        match &mut self.inner {
+            InnerNetworkStream::Tcp(stream) => stream.set_read_timeout(duration),
             #[cfg(feature = "native-tls")]
-            InnerNetworkStream::NativeTls(ref mut stream) => {
-                stream.get_ref().set_read_timeout(duration)
-            }
+            InnerNetworkStream::NativeTls(stream) => stream.get_ref().set_read_timeout(duration),
             #[cfg(feature = "rustls-tls")]
-            InnerNetworkStream::RustlsTls(ref mut stream) => {
-                stream.get_ref().set_read_timeout(duration)
-            }
+            InnerNetworkStream::RustlsTls(stream) => stream.get_ref().set_read_timeout(duration),
             #[cfg(feature = "boring-tls")]
-            InnerNetworkStream::BoringTls(ref mut stream) => {
-                stream.get_ref().set_read_timeout(duration)
-            }
-            InnerNetworkStream::None => {
-                debug_assert!(false, "InnerNetworkStream::None must never be built");
-                Ok(())
-            }
+            InnerNetworkStream::BoringTls(stream) => stream.get_ref().set_read_timeout(duration),
         }
     }
 
     /// Set write timeout for IO calls
     pub fn set_write_timeout(&mut self, duration: Option<Duration>) -> io::Result<()> {
-        match self.inner {
-            InnerNetworkStream::Tcp(ref mut stream) => stream.set_write_timeout(duration),
+        match &mut self.inner {
+            InnerNetworkStream::Tcp(stream) => stream.set_write_timeout(duration),
 
             #[cfg(feature = "native-tls")]
-            InnerNetworkStream::NativeTls(ref mut stream) => {
-                stream.get_ref().set_write_timeout(duration)
-            }
+            InnerNetworkStream::NativeTls(stream) => stream.get_ref().set_write_timeout(duration),
             #[cfg(feature = "rustls-tls")]
-            InnerNetworkStream::RustlsTls(ref mut stream) => {
-                stream.get_ref().set_write_timeout(duration)
-            }
+            InnerNetworkStream::RustlsTls(stream) => stream.get_ref().set_write_timeout(duration),
             #[cfg(feature = "boring-tls")]
-            InnerNetworkStream::BoringTls(ref mut stream) => {
-                stream.get_ref().set_write_timeout(duration)
-            }
-            InnerNetworkStream::None => {
-                debug_assert!(false, "InnerNetworkStream::None must never be built");
-                Ok(())
-            }
+            InnerNetworkStream::BoringTls(stream) => stream.get_ref().set_write_timeout(duration),
         }
     }
 }
 
 impl Read for NetworkStream {
     fn read(&mut self, buf: &mut [u8]) -> io::Result<usize> {
-        match self.inner {
-            InnerNetworkStream::Tcp(ref mut s) => s.read(buf),
+        match &mut self.inner {
+            InnerNetworkStream::Tcp(s) => s.read(buf),
             #[cfg(feature = "native-tls")]
-            InnerNetworkStream::NativeTls(ref mut s) => s.read(buf),
+            InnerNetworkStream::NativeTls(s) => s.read(buf),
             #[cfg(feature = "rustls-tls")]
-            InnerNetworkStream::RustlsTls(ref mut s) => s.read(buf),
+            InnerNetworkStream::RustlsTls(s) => s.read(buf),
             #[cfg(feature = "boring-tls")]
-            InnerNetworkStream::BoringTls(ref mut s) => s.read(buf),
-            InnerNetworkStream::None => {
-                debug_assert!(false, "InnerNetworkStream::None must never be built");
-                Ok(0)
-            }
+            InnerNetworkStream::BoringTls(s) => s.read(buf),
         }
     }
 }
 
 impl Write for NetworkStream {
     fn write(&mut self, buf: &[u8]) -> io::Result<usize> {
-        match self.inner {
-            InnerNetworkStream::Tcp(ref mut s) => s.write(buf),
+        match &mut self.inner {
+            InnerNetworkStream::Tcp(s) => s.write(buf),
             #[cfg(feature = "native-tls")]
-            InnerNetworkStream::NativeTls(ref mut s) => s.write(buf),
+            InnerNetworkStream::NativeTls(s) => s.write(buf),
             #[cfg(feature = "rustls-tls")]
-            InnerNetworkStream::RustlsTls(ref mut s) => s.write(buf),
+            InnerNetworkStream::RustlsTls(s) => s.write(buf),
             #[cfg(feature = "boring-tls")]
-            InnerNetworkStream::BoringTls(ref mut s) => s.write(buf),
-            InnerNetworkStream::None => {
-                debug_assert!(false, "InnerNetworkStream::None must never be built");
-                Ok(0)
-            }
+            InnerNetworkStream::BoringTls(s) => s.write(buf),
         }
     }
 
     fn flush(&mut self) -> io::Result<()> {
-        match self.inner {
-            InnerNetworkStream::Tcp(ref mut s) => s.flush(),
+        match &mut self.inner {
+            InnerNetworkStream::Tcp(s) => s.flush(),
             #[cfg(feature = "native-tls")]
-            InnerNetworkStream::NativeTls(ref mut s) => s.flush(),
+            InnerNetworkStream::NativeTls(s) => s.flush(),
             #[cfg(feature = "rustls-tls")]
-            InnerNetworkStream::RustlsTls(ref mut s) => s.flush(),
+            InnerNetworkStream::RustlsTls(s) => s.flush(),
             #[cfg(feature = "boring-tls")]
-            InnerNetworkStream::BoringTls(ref mut s) => s.flush(),
-            InnerNetworkStream::None => {
-                debug_assert!(false, "InnerNetworkStream::None must never be built");
-                Ok(())
-            }
+            InnerNetworkStream::BoringTls(s) => s.flush(),
         }
     }
 }

src/transport/smtp/client/tls.rs

@@ -1,6 +1,6 @@
 use std::fmt::{self, Debug};
 #[cfg(feature = "rustls-tls")]
-use std::{sync::Arc, time::SystemTime};
+use std::{io, sync::Arc};
 
 #[cfg(feature = "boring-tls")]
 use boring::{
@@ -11,8 +11,10 @@ use boring::{
 use native_tls::{Protocol, TlsConnector};
 #[cfg(feature = "rustls-tls")]
 use rustls::{
-    client::{ServerCertVerified, ServerCertVerifier, WebPkiVerifier},
-    ClientConfig, Error as TlsError, RootCertStore, ServerName,
+    client::danger::{HandshakeSignatureValid, ServerCertVerified, ServerCertVerifier},
+    crypto::{verify_tls12_signature, verify_tls13_signature},
+    pki_types::{CertificateDer, ServerName, UnixTime},
+    ClientConfig, DigitallySignedStruct, Error as TlsError, RootCertStore, SignatureScheme,
 };
 
 #[cfg(any(feature = "native-tls", feature = "rustls-tls", feature = "boring-tls"))]
@@ -337,8 +339,6 @@ impl TlsParametersBuilder {
     #[cfg(feature = "rustls-tls")]
     #[cfg_attr(docsrs, doc(cfg(feature = "rustls-tls")))]
     pub fn build_rustls(self) -> Result<TlsParameters, Error> {
-        let tls = ClientConfig::builder();
-
         let just_version3 = &[&rustls::version::TLS13];
         let supported_versions = match self.min_tls_version {
             TlsVersion::Tlsv10 => {
@@ -351,50 +351,28 @@ impl TlsParametersBuilder {
             TlsVersion::Tlsv13 => just_version3,
         };
 
-        let tls = tls
-            .with_safe_default_cipher_suites()
-            .with_safe_default_kx_groups()
-            .with_protocol_versions(supported_versions)
-            .map_err(error::tls)?;
+        let tls = ClientConfig::builder_with_protocol_versions(supported_versions);
 
         let tls = if self.accept_invalid_certs {
-            tls.with_custom_certificate_verifier(Arc::new(InvalidCertsVerifier {}))
+            tls.dangerous()
+                .with_custom_certificate_verifier(Arc::new(InvalidCertsVerifier {}))
         } else {
             let mut root_cert_store = RootCertStore::empty();
 
             #[cfg(feature = "rustls-native-certs")]
             fn load_native_roots(store: &mut RootCertStore) -> Result<(), Error> {
                 let native_certs = rustls_native_certs::load_native_certs().map_err(error::tls)?;
-                let mut valid_count = 0;
-                let mut invalid_count = 0;
-                for cert in native_certs {
-                    match store.add(&rustls::Certificate(cert.0)) {
-                        Ok(_) => valid_count += 1,
-                        Err(err) => {
-                            #[cfg(feature = "tracing")]
-                            tracing::debug!("certificate parsing failed: {:?}", err);
-                            invalid_count += 1;
-                        }
-                    }
-                }
+                let (added, ignored) = store.add_parsable_certificates(native_certs);
                 #[cfg(feature = "tracing")]
                 tracing::debug!(
-                    "loaded platform certs with {valid_count} valid and {invalid_count} invalid certs"
+                    "loaded platform certs with {added} valid and {ignored} ignored (invalid) certs"
                 );
                 Ok(())
             }
 
             #[cfg(feature = "rustls-tls")]
             fn load_webpki_roots(store: &mut RootCertStore) {
-                // TODO: handle this in the rustls 0.22 upgrade
-                #[allow(deprecated)]
-                store.add_server_trust_anchors(webpki_roots::TLS_SERVER_ROOTS.iter().map(|ta| {
-                    rustls::OwnedTrustAnchor::from_subject_spki_name_constraints(
-                        ta.subject,
-                        ta.spki,
-                        ta.name_constraints,
-                    )
-                }));
+                store.extend(webpki_roots::TLS_SERVER_ROOTS.iter().cloned());
             }
 
             match self.cert_store {
@@ -412,14 +390,11 @@ impl TlsParametersBuilder {
             }
             for cert in self.root_certs {
                 for rustls_cert in cert.rustls {
-                    root_cert_store.add(&rustls_cert).map_err(error::tls)?;
+                    root_cert_store.add(rustls_cert).map_err(error::tls)?;
                 }
             }
 
-            tls.with_custom_certificate_verifier(Arc::new(WebPkiVerifier::new(
-                root_cert_store,
-                None,
-            )))
+            tls.with_root_certificates(root_cert_store)
         };
         let tls = tls.with_no_client_auth();
 
@@ -493,7 +468,7 @@ pub struct Certificate {
     #[cfg(feature = "native-tls")]
     native_tls: native_tls::Certificate,
     #[cfg(feature = "rustls-tls")]
-    rustls: Vec<rustls::Certificate>,
+    rustls: Vec<CertificateDer<'static>>,
     #[cfg(feature = "boring-tls")]
     boring_tls: boring::x509::X509,
 }
@@ -512,7 +487,7 @@ impl Certificate {
             #[cfg(feature = "native-tls")]
             native_tls: native_tls_cert,
             #[cfg(feature = "rustls-tls")]
-            rustls: vec![rustls::Certificate(der)],
+            rustls: vec![der.into()],
             #[cfg(feature = "boring-tls")]
             boring_tls: boring_tls_cert,
         })
@@ -532,10 +507,8 @@ impl Certificate {
 
             let mut pem = Cursor::new(pem);
             rustls_pemfile::certs(&mut pem)
+                .collect::<io::Result<Vec<_>>>()
                 .map_err(|_| error::tls("invalid certificates"))?
-                .into_iter()
-                .map(rustls::Certificate)
-                .collect::<Vec<_>>()
         };
 
         Ok(Self {
@@ -556,19 +529,53 @@ impl Debug for Certificate {
 }
 
 #[cfg(feature = "rustls-tls")]
+#[derive(Debug)]
 struct InvalidCertsVerifier;
 
 #[cfg(feature = "rustls-tls")]
 impl ServerCertVerifier for InvalidCertsVerifier {
     fn verify_server_cert(
         &self,
-        _end_entity: &rustls::Certificate,
-        _intermediates: &[rustls::Certificate],
-        _server_name: &ServerName,
-        _scts: &mut dyn Iterator<Item = &[u8]>,
+        _end_entity: &CertificateDer<'_>,
+        _intermediates: &[CertificateDer<'_>],
+        _server_name: &ServerName<'_>,
         _ocsp_response: &[u8],
-        _now: SystemTime,
+        _now: UnixTime,
     ) -> Result<ServerCertVerified, TlsError> {
         Ok(ServerCertVerified::assertion())
     }
+
+    fn verify_tls12_signature(
+        &self,
+        message: &[u8],
+        cert: &CertificateDer<'_>,
+        dss: &DigitallySignedStruct,
+    ) -> Result<HandshakeSignatureValid, TlsError> {
+        verify_tls12_signature(
+            message,
+            cert,
+            dss,
+            &rustls::crypto::ring::default_provider().signature_verification_algorithms,
+        )
+    }
+
+    fn verify_tls13_signature(
+        &self,
+        message: &[u8],
+        cert: &CertificateDer<'_>,
+        dss: &DigitallySignedStruct,
+    ) -> Result<HandshakeSignatureValid, TlsError> {
+        verify_tls13_signature(
+            message,
+            cert,
+            dss,
+            &rustls::crypto::ring::default_provider().signature_verification_algorithms,
+        )
+    }
+
+    fn supported_verify_schemes(&self) -> Vec<SignatureScheme> {
+        rustls::crypto::ring::default_provider()
+            .signature_verification_algorithms
+            .supported_schemes()
+    }
 }

src/transport/smtp/connection_url.rs

@@ -112,7 +112,16 @@ pub(crate) fn from_connection_url<B: TransportBuilder>(connection_url: &str) ->
     }
 
     if let Some(password) = connection_url.password() {
-        let credentials = Credentials::new(connection_url.username().into(), password.into());
+        let percent_decode = |s: &str| {
+            percent_encoding::percent_decode_str(s)
+                .decode_utf8()
+                .map(|cow| cow.into_owned())
+                .map_err(error::connection)
+        };
+        let credentials = Credentials::new(
+            percent_decode(connection_url.username())?,
+            percent_decode(password)?,
+        );
         builder = builder.credentials(credentials);
     }
 

src/transport/smtp/error.rs

@@ -119,7 +119,7 @@ impl fmt::Debug for Error {
 
         builder.field("kind", &self.inner.kind);
 
-        if let Some(ref source) = self.inner.source {
+        if let Some(source) = &self.inner.source {
             builder.field("source", source);
         }
 
@@ -129,22 +129,22 @@ impl fmt::Debug for Error {
 
 impl fmt::Display for Error {
     fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        match self.inner.kind {
+        match &self.inner.kind {
             Kind::Response => f.write_str("response error")?,
             Kind::Client => f.write_str("internal client error")?,
             Kind::Network => f.write_str("network error")?,
             Kind::Connection => f.write_str("Connection error")?,
             #[cfg(any(feature = "native-tls", feature = "rustls-tls", feature = "boring-tls"))]
             Kind::Tls => f.write_str("tls error")?,
-            Kind::Transient(ref code) => {
+            Kind::Transient(code) => {
                 write!(f, "transient error ({code})")?;
             }
-            Kind::Permanent(ref code) => {
+            Kind::Permanent(code) => {
                 write!(f, "permanent error ({code})")?;
             }
         };
 
-        if let Some(ref e) = self.inner.source {
+        if let Some(e) = &self.inner.source {
             write!(f, ": {e}")?;
         }
 

src/transport/smtp/extension.rs

@@ -4,7 +4,6 @@ use std::{
     collections::HashSet,
     fmt::{self, Display, Formatter},
     net::{Ipv4Addr, Ipv6Addr},
-    result::Result,
 };
 
 use crate::transport::smtp::{
@@ -53,10 +52,10 @@ impl Default for ClientId {
 
 impl Display for ClientId {
     fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
-        match *self {
-            Self::Domain(ref value) => f.write_str(value),
-            Self::Ipv4(ref value) => write!(f, "[{value}]"),
-            Self::Ipv6(ref value) => write!(f, "[IPv6:{value}]"),
+        match self {
+            Self::Domain(value) => f.write_str(value),
+            Self::Ipv4(value) => write!(f, "[{value}]"),
+            Self::Ipv6(value) => write!(f, "[IPv6:{value}]"),
         }
     }
 }
@@ -93,11 +92,11 @@ pub enum Extension {
 
 impl Display for Extension {
     fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
-        match *self {
+        match self {
             Extension::EightBitMime => f.write_str("8BITMIME"),
             Extension::SmtpUtfEight => f.write_str("SMTPUTF8"),
             Extension::StartTls => f.write_str("STARTTLS"),
-            Extension::Authentication(ref mechanism) => write!(f, "AUTH {mechanism}"),
+            Extension::Authentication(mechanism) => write!(f, "AUTH {mechanism}"),
         }
     }
 }
@@ -227,16 +226,16 @@ pub enum MailParameter {
 
 impl Display for MailParameter {
     fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
-        match *self {
-            MailParameter::Body(ref value) => write!(f, "BODY={value}"),
+        match self {
+            MailParameter::Body(value) => write!(f, "BODY={value}"),
             MailParameter::Size(size) => write!(f, "SIZE={size}"),
             MailParameter::SmtpUtfEight => f.write_str("SMTPUTF8"),
             MailParameter::Other {
-                ref keyword,
-                value: Some(ref value),
+                keyword,
+                value: Some(value),
             } => write!(f, "{}={}", keyword, XText(value)),
             MailParameter::Other {
-                ref keyword,
+                keyword,
                 value: None,
             } => f.write_str(keyword),
         }
@@ -277,13 +276,13 @@ pub enum RcptParameter {
 
 impl Display for RcptParameter {
     fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
-        match *self {
+        match &self {
             RcptParameter::Other {
-                ref keyword,
-                value: Some(ref value),
+                keyword,
+                value: Some(value),
             } => write!(f, "{keyword}={}", XText(value)),
             RcptParameter::Other {
-                ref keyword,
+                keyword,
                 value: None,
             } => f.write_str(keyword),
         }

src/transport/smtp/pool/async_impl.rs

@@ -2,7 +2,7 @@ use std::{
     fmt::{self, Debug},
     mem,
     ops::{Deref, DerefMut},
-    sync::Arc,
+    sync::{Arc, OnceLock},
     time::{Duration, Instant},
 };
 
@@ -10,7 +10,6 @@ use futures_util::{
     lock::Mutex,
     stream::{self, StreamExt},
 };
-use once_cell::sync::OnceCell;
 
 use super::{
     super::{client::AsyncSmtpConnection, Error},
@@ -22,7 +21,7 @@ pub struct Pool<E: Executor> {
     config: PoolConfig,
     connections: Mutex<Vec<ParkedConnection>>,
     client: AsyncSmtpClient<E>,
-    handle: OnceCell<E::Handle>,
+    handle: OnceLock<E::Handle>,
 }
 
 struct ParkedConnection {
@@ -41,7 +40,7 @@ impl<E: Executor> Pool<E> {
             config,
             connections: Mutex::new(Vec::new()),
             client,
-            handle: OnceCell::new(),
+            handle: OnceLock::new(),
         });
 
         {

src/transport/smtp/response.rs

@@ -5,7 +5,6 @@ use std::{
     fmt::{Display, Formatter, Result},
     result,
     str::FromStr,
-    string::ToString,
 };
 
 use nom::{
@@ -132,6 +131,12 @@ impl Code {
     }
 }
 
+impl From<Code> for u16 {
+    fn from(code: Code) -> Self {
+        code.detail as u16 + 10 * code.category as u16 + 100 * code.severity as u16
+    }
+}
+
 /// Contains an SMTP reply, with separated code and message
 ///
 /// The text message is optional, only the code is mandatory
@@ -317,6 +322,17 @@ mod test {
         assert_eq!(code.to_string(), "421");
     }
 
+    #[test]
+    fn test_code_to_u16() {
+        let code = Code {
+            severity: Severity::TransientNegativeCompletion,
+            category: Category::Connections,
+            detail: Detail::One,
+        };
+        let c: u16 = code.into();
+        assert_eq!(c, 421);
+    }
+
     #[test]
     fn test_response_from_str() {
         let raw_response = "250-me\r\n250-8BITMIME\r\n250-SIZE 42\r\n250 AUTH PLAIN CRAM-MD5\r\n";

src/transport/smtp/transport.rs

@@ -1,6 +1,6 @@
 #[cfg(feature = "pool")]
 use std::sync::Arc;
-use std::time::Duration;
+use std::{fmt::Debug, time::Duration};
 
 #[cfg(feature = "pool")]
 use super::pool::sync_impl::Pool;
@@ -38,6 +38,14 @@ impl Transport for SmtpTransport {
     }
 }
 
+impl Debug for SmtpTransport {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        let mut builder = f.debug_struct("SmtpTransport");
+        builder.field("inner", &self.inner);
+        builder.finish()
+    }
+}
+
 impl SmtpTransport {
     /// Simple and secure transport, using TLS connections to communicate with the SMTP server
     ///
@@ -309,9 +317,9 @@ impl SmtpClient {
     /// Handles encryption and authentication
     pub fn connection(&self) -> Result<SmtpConnection, Error> {
         #[allow(clippy::match_single_binding)]
-        let tls_parameters = match self.info.tls {
+        let tls_parameters = match &self.info.tls {
             #[cfg(any(feature = "native-tls", feature = "rustls-tls", feature = "boring-tls"))]
-            Tls::Wrapper(ref tls_parameters) => Some(tls_parameters),
+            Tls::Wrapper(tls_parameters) => Some(tls_parameters),
             _ => None,
         };
 
@@ -325,14 +333,14 @@ impl SmtpClient {
         )?;
 
         #[cfg(any(feature = "native-tls", feature = "rustls-tls", feature = "boring-tls"))]
-        match self.info.tls {
-            Tls::Opportunistic(ref tls_parameters) => {
+        match &self.info.tls {
+            Tls::Opportunistic(tls_parameters) => {
                 if conn.can_starttls() {
-                    conn.starttls(tls_parameters, &self.info.hello_name)?;
+                    conn = conn.starttls(tls_parameters, &self.info.hello_name)?;
                 }
             }
-            Tls::Required(ref tls_parameters) => {
-                conn.starttls(tls_parameters, &self.info.hello_name)?;
+            Tls::Required(tls_parameters) => {
+                conn = conn.starttls(tls_parameters, &self.info.hello_name)?;
             }
             _ => (),
         }
@@ -373,6 +381,22 @@ mod tests {
         assert!(matches!(builder.info.tls, Tls::Wrapper(_)));
         assert_eq!(builder.info.server, "smtp.example.com");
 
+        let builder = SmtpTransport::from_url(
+            "smtps://user%40example.com:pa$$word%3F%22!@smtp.example.com:465",
+        )
+        .unwrap();
+
+        assert_eq!(builder.info.port, 465);
+        assert_eq!(
+            builder.info.credentials,
+            Some(Credentials::new(
+                "user@example.com".to_owned(),
+                "pa$$word?\"!".to_owned()
+            ))
+        );
+        assert!(matches!(builder.info.tls, Tls::Wrapper(_)));
+        assert_eq!(builder.info.server, "smtp.example.com");
+
         let builder =
             SmtpTransport::from_url("smtp://username:password@smtp.example.com:587?tls=required")
                 .unwrap();