Explicit prudence for badly behaved clients

.gitignore

@@ -4,4 +4,5 @@
 target/
 .cargo/
 /*.log
-tmp/
\ No newline at end of file
+tmp/
+*.pending-snap
\ No newline at end of file

.gitlab-ci.yml

@@ -13,6 +13,7 @@ debug-build:
   stage: build
   only:
     - branches
+  interruptible: true
   cache:
     key: &cache-key
       files:
@@ -42,6 +43,7 @@ release-build:
     - /^release\/*/
     - /^hotfix\/*/
     - master
+  interruptible: true
   cache:
     key: *cache-key
     paths: *cache-paths
@@ -61,6 +63,7 @@ stable-test:
   stage: build
   only:
     - branches
+  interruptible: true
   cache:
     key: *cache-key
     paths: *cache-paths
@@ -90,6 +93,7 @@ audit-test:
 nightly-test:
   stage: build
   allow_failure: true
+  interruptible: true
   variables:
     RUST_BACKTRACE: 1
   only:
@@ -115,6 +119,7 @@ nightly-test:
   stage: build
   only:
     - branches
+  interruptible: true
   cache:
     key: *cache-key
     paths: *cache-paths
@@ -122,10 +127,10 @@ nightly-test:
   before_script:
     - rustc --version --verbose
     - cargo --version --verbose
+    - cargo build --example ${EXAMPLE:?} --color always
   variables:
     INPUT: samotop/examples/mailsession.txt
   script:
-    - cargo build --example ${EXAMPLE:?} --color always
     - RUST_LOG=trace cargo run --example ${EXAMPLE:?} &
     - sleep 5
     - nc localhost 2525 <"$INPUT" >client.log
@@ -153,6 +158,18 @@ example-dir:
     EXAMPLE: to-dirmail
     OUTPUT: samotop/examples/mailbody.txt
 
+example-prudence:
+  extends: .example-template
+  variables:
+    EXAMPLE: prudent
+  script:
+    - RUST_LOG=trace cargo run --example ${EXAMPLE:?} &
+    - sleep 5
+    - echo ehlo booo | nc -C localhost 2525 | tee bad-client.log
+    - nc -w 10 -C 127.0.0.1 2525 | tee good-client.log
+    - diff bad-client.log samotop/examples/prudence-bad.txt
+    - diff good-client.log samotop/examples/prudence-good.txt
+
 example-cmd:
   extends: .example-template
   variables:
@@ -160,7 +177,6 @@ example-cmd:
     INPUT: samotop/examples/mailsessionlmtp.txt
     OUTPUT: samotop/examples/mailbody.txt
   script:
-    - cargo build --example ${EXAMPLE:?}
     - cargo run --example ${EXAMPLE:?} <"$INPUT" >client.log
     - cat "$INPUT"
     - cat client.log
@@ -198,6 +214,7 @@ server-version:
     - echo "SAMOTOP_VERSION=$SAMOTOP_VERSION" > vars.env
     - echo "SAMOTOP_IMAGE=$CI_REGISTRY_IMAGE/samotop:$SAMOTOP_VERSION" >> vars.env
     - cat vars.env
+  interruptible: true
   cache:
     key: *cache-key
     paths: *cache-paths
@@ -209,6 +226,7 @@ server-version:
 server-docker-image:
   extends: .kaniko-build-template
   stage: release
+  interruptible: true
   variables:
     COMPONENT: samotop
     CONTEXT: .

Cargo.lock

@@ -279,27 +279,6 @@ dependencies = [
  "wyz",
 ]
 
-[[package]]
-name = "block-buffer"
-version = "0.7.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c0940dc441f31689269e10ac70eb1002a3a1d3ad1390e030043662eb7fe4688b"
-dependencies = [
- "block-padding",
- "byte-tools",
- "byteorder",
- "generic-array",
-]
-
-[[package]]
-name = "block-padding"
-version = "0.1.5"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fa79dedbb091f449f1f39e53edf88d5dbe95f895dae6135a8d7b881fb5af73f5"
-dependencies = [
- "byte-tools",
-]
-
 [[package]]
 name = "blocking"
 version = "1.0.2"
@@ -332,18 +311,6 @@ version = "3.7.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "9c59e7af012c713f529e7a3ee57ce9b31ddd858d4b512923602f74608b009631"
 
-[[package]]
-name = "byte-tools"
-version = "0.3.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e3b5ca7a04898ad4bcd41c90c5285445ff5b791899bb1b0abdd2a2aa791211d7"
-
-[[package]]
-name = "byteorder"
-version = "1.4.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "14c189c53d098945499cdfa7ecc63567cf3886b3332b312a5b4585d8d3a6a610"
-
 [[package]]
 name = "bytes"
 version = "1.0.1"
@@ -358,18 +325,18 @@ checksum = "631ae5198c9be5e753e5cc215e1bd73c2b466a3565173db433f52bb9d3e66dba"
 
 [[package]]
 name = "cast"
-version = "0.2.6"
+version = "0.2.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "57cdfa5d50aad6cb4d44dcab6101a7f79925bd59d82ca42f38a9856a28865374"
+checksum = "4c24dab4283a142afa2fdca129b80ad2c6284e073930f964c3a1293c225ee39a"
 dependencies = [
  "rustc_version",
 ]
 
 [[package]]
 name = "cc"
-version = "1.0.68"
+version = "1.0.69"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "4a72c244c1ff497a746a7e1fb3d14bd08420ecda70c8f25c7112f2781652d787"
+checksum = "e70cc2f62c6ce1868963827bd677764c62d07c3d9a3e1fb1177ee1a9ab199eb2"
 
 [[package]]
 name = "cfg-if"
@@ -548,15 +515,6 @@ version = "2.3.2"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3ee2393c4a91429dffb4bedf19f4d6abf27d8a732c8ce4980305d782e5426d57"
 
-[[package]]
-name = "digest"
-version = "0.8.1"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f3d0c8c8752312f9713efd397ff63acb9f85585afbf179282e720e7704954dd5"
-dependencies = [
- "generic-array",
-]
-
 [[package]]
 name = "dtoa"
 version = "0.4.8"
@@ -670,12 +628,6 @@ version = "2.5.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "f7531096570974c3a9dcf9e4b8e1cede1ec26cf5046219fb3b9d897503b9be59"
 
-[[package]]
-name = "fake-simd"
-version = "0.1.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "e88a8acf291dafb59c2d96e8f59828f3838bb1a70398823ade51a84de6a6deed"
-
 [[package]]
 name = "fast_chemail"
 version = "0.9.6"
@@ -687,9 +639,9 @@ dependencies = [
 
 [[package]]
 name = "fastrand"
-version = "1.4.1"
+version = "1.5.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "77b705829d1e87f762c2df6da140b26af5839e1033aa84aa5f56bb688e4e1bdb"
+checksum = "b394ed3d285a429378d3b384b9eb1285267e7df4b166df24b7a6939a04dc392e"
 dependencies = [
  "instant",
 ]
@@ -781,15 +733,6 @@ dependencies = [
  "slab",
 ]
 
-[[package]]
-name = "generic-array"
-version = "0.12.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ffdf9f34f1447443d37393cc6c2b8313aebddcd96906caf34e54c68d8e57d7bd"
-dependencies = [
- "typenum",
-]
-
 [[package]]
 name = "getrandom"
 version = "0.2.3"
@@ -886,8 +829,6 @@ checksum = "c4a1b21a2971cea49ca4613c0e9fe8225ecaf5de64090fddc6002284726e9244"
 dependencies = [
  "console",
  "lazy_static",
- "pest",
- "pest_derive",
  "serde",
  "serde_json",
  "serde_yaml",
@@ -897,9 +838,9 @@ dependencies = [
 
 [[package]]
 name = "instant"
-version = "0.1.9"
+version = "0.1.10"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "61124eeebbd69b8190558df225adf7e4caafce0d743919e5d6b19652314ec5ec"
+checksum = "bee0328b1209d157ef001c94dd85b4f8f64139adb0eac2659f4b08382b2f474d"
 dependencies = [
  "cfg-if",
 ]
@@ -985,9 +926,9 @@ dependencies = [
 
 [[package]]
 name = "libc"
-version = "0.2.97"
+version = "0.2.98"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "12b8adadd720df158f4d70dfe7ccc6adb0472d7c55ca83445f6a5ab3e36f8fb6"
+checksum = "320cfe77175da3a483efed4bc0adc1968ca050b098ce4f2f1c13a56626128790"
 
 [[package]]
 name = "linked-hash-map"
@@ -1037,12 +978,6 @@ dependencies = [
  "linked-hash-map",
 ]
 
-[[package]]
-name = "maplit"
-version = "1.0.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "3e2e65a1a2e43cfcb47a895c4c8b10d1f4a61097f9f254f183aee60cad9c651d"
-
 [[package]]
 name = "match_cfg"
 version = "0.1.0"
@@ -1132,12 +1067,6 @@ version = "11.1.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0ab1bc2a289d34bd04a330323ac98a1b4bc82c9d9fcb1e66b63caa84da26b575"
 
-[[package]]
-name = "opaque-debug"
-version = "0.2.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2839e79665f131bdb5782e51f2c6c9599c133c6098982a54c794358bf432529c"
-
 [[package]]
 name = "openssl"
 version = "0.10.35"
@@ -1245,49 +1174,6 @@ version = "2.1.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d4fd5641d01c8f18a23da7b6fe29298ff4b55afcccdf78973b24cf3175fee32e"
 
-[[package]]
-name = "pest"
-version = "2.1.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "10f4872ae94d7b90ae48754df22fd42ad52ce740b8f370b03da4835417403e53"
-dependencies = [
- "ucd-trie",
-]
-
-[[package]]
-name = "pest_derive"
-version = "2.1.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "833d1ae558dc601e9a60366421196a8d94bc0ac980476d0b67e1d0988d72b2d0"
-dependencies = [
- "pest",
- "pest_generator",
-]
-
-[[package]]
-name = "pest_generator"
-version = "2.1.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "99b8db626e31e5b81787b9783425769681b347011cc59471e33ea46d2ea0cf55"
-dependencies = [
- "pest",
- "pest_meta",
- "proc-macro2",
- "quote",
- "syn",
-]
-
-[[package]]
-name = "pest_meta"
-version = "2.1.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "54be6e404f5317079812fc8f9f5279de376d8856929e21c184ecf6bbd692a11d"
-dependencies = [
- "maplit",
- "pest",
- "sha-1",
-]
-
 [[package]]
 name = "pin-project"
 version = "1.0.7"
@@ -1571,9 +1457,9 @@ dependencies = [
 
 [[package]]
 name = "rustc_version"
-version = "0.3.3"
+version = "0.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f0dfe2087c51c460008730de8b57e6a320782fbfb312e1f4d520e6c6fae155ee"
+checksum = "bfa0f585226d2e68097d4f95d113b15b83a82e819ab25717ec0590d9584ef366"
 dependencies = [
  "semver",
 ]
@@ -1643,6 +1529,7 @@ version = "0.13.0-samotop-dev"
 dependencies = [
  "async-std",
  "futures-util",
+ "insta",
  "log",
 ]
 
@@ -1801,21 +1688,9 @@ dependencies = [
 
 [[package]]
 name = "semver"
-version = "0.11.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f301af10236f6df4160f7c3f04eec6dbc70ace82d23326abad5edee88801c6b6"
-dependencies = [
- "semver-parser",
-]
-
-[[package]]
-name = "semver-parser"
-version = "0.10.2"
+version = "1.0.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "00b0bef5b7f9e0df16536d3961cfb6e84331c065b4066afb39768d0e319411f7"
-dependencies = [
- "pest",
-]
+checksum = "5f3aac57ee7f3272d8395c6e4f502f434f0e289fcd62876f70daa008c20dcabe"
 
 [[package]]
 name = "serde"
@@ -1870,18 +1745,6 @@ dependencies = [
  "yaml-rust",
 ]
 
-[[package]]
-name = "sha-1"
-version = "0.8.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f7d94d0bede923b3cea61f3f1ff57ff8cdfd77b400fb8f9998949e0cf04163df"
-dependencies = [
- "block-buffer",
- "digest",
- "fake-simd",
- "opaque-debug",
-]
-
 [[package]]
 name = "signal-hook"
 version = "0.3.9"
@@ -1960,9 +1823,9 @@ checksum = "8ea5119cdb4c55b55d432abb513a0429384878c15dde60cc77b1c99de1a95a6a"
 
 [[package]]
 name = "structopt"
-version = "0.3.21"
+version = "0.3.22"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5277acd7ee46e63e5168a80734c9f6ee81b1367a7d8772a2d765df2a3705d28c"
+checksum = "69b041cdcb67226aca307e6e7be44c8806423d83e018bd662360a93dabce4d71"
 dependencies = [
  "clap",
  "lazy_static",
@@ -1971,9 +1834,9 @@ dependencies = [
 
 [[package]]
 name = "structopt-derive"
-version = "0.4.14"
+version = "0.4.15"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "5ba9cdfda491b814720b6b06e0cac513d922fc407582032e8706e9f137976f90"
+checksum = "7813934aecf5f51a54775e00068c237de98489463968231a51746bbbc03f9c10"
 dependencies = [
  "heck",
  "proc-macro-error",
@@ -2043,18 +1906,18 @@ dependencies = [
 
 [[package]]
 name = "thiserror"
-version = "1.0.25"
+version = "1.0.26"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fa6f76457f59514c7eeb4e59d891395fab0b2fd1d40723ae737d64153392e9c6"
+checksum = "93119e4feac1cbe6c798c34d3a53ea0026b0b1de6a120deef895137c0529bfe2"
 dependencies = [
  "thiserror-impl",
 ]
 
 [[package]]
 name = "thiserror-impl"
-version = "1.0.25"
+version = "1.0.26"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8a36768c0fbf1bb15eca10defa29526bda730a2376c2ab4393ccfa16fb1a318d"
+checksum = "060d69a0afe7796bf42e9e2ff91f5ee691fb15c53d38b4b62a9a53eb23164745"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -2129,18 +1992,6 @@ dependencies = [
  "trust-dns-proto",
 ]
 
-[[package]]
-name = "typenum"
-version = "1.13.0"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "879f6906492a7cd215bfa4cf595b600146ccfac0c79bcbd1f3000162af5e8b06"
-
-[[package]]
-name = "ucd-trie"
-version = "0.1.3"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "56dee185309b50d1f11bfedef0fe6d036842e3fb77413abef29f8f8d1c5d4c1c"
-
 [[package]]
 name = "unicode-bidi"
 version = "0.3.5"

samotop-core/Cargo.toml

@@ -13,13 +13,16 @@ edition = "2018"
 categories = ["email", "asynchronous", "network-programming"]
 
 [badges]
-gitlab = { repository="BrightOpen/Samotop", branch="develop" }
-maintenance = { status="actively-developed" }
+gitlab = { repository = "BrightOpen/Samotop", branch = "develop" }
+maintenance = { status = "actively-developed" }
 
 [features]
 server = ["futures-util"]
 
 [dependencies]
-futures-util = { version="0.3", default-features=false, optional=true }
-async-std = { version="1.9", default-features=false }
+futures-util = { version = "0.3", default-features = false, optional = true }
+async-std = { version = "1.9", default-features = false }
 log = "0.4"
+
+[dev-dependencies]
+insta = { version = "1.7" }

samotop-core/src/io/dummy.rs

@@ -3,10 +3,7 @@ use crate::io::tls::MayBeTls;
 use crate::io::ConnectionInfo;
 use crate::io::IoService;
 
-/// Logs an incomming connection on info level and that's it.
-#[doc = "Dummy TCP service for testing samotop server"]
-#[derive(Clone, Debug)]
-pub struct DummyService;
+pub use crate::common::Dummy as DummyService;
 
 impl IoService for DummyService {
     fn handle(

samotop-core/src/io/mod.rs

 mod connection;
-pub mod dummy;
+mod dummy;
 mod service;
-pub mod smtp;
 pub mod tls;
 
 pub use self::connection::*;
+pub use self::dummy::*;
 pub use self::service::*;

samotop-core/src/io/smtp.rs

-use crate::{
-    common::*,
-    io::{
-        tls::{Io, MayBeTls, TlsCapable},
-        ConnectionInfo, IoService,
-    },
-    mail::{Esmtp, MailService, SessionInfo},
-    smtp::*,
-};
-
-/// `SmtpService` provides a stateful SMTP service on a TCP, Unix or other asyn IO conection.
-///
-/// It uses the given `MailService` which takes care of mail events:
-/// * session setup - upon a new connection
-/// * opening new mail transaction - MAIL FROM:<x@y.z>
-/// * adding recipients - RCPT FROM:<a@b.c>
-/// * streaming data - DATA...
-///
-/// It uses the given `Parser` to extract SMTP commands from the input strings.
-/// This is essential because the commands drive the session. All commands
-/// are `apply()`d to the `SmtpState`.
-///
-/// Internally it uses the `SmtpDriver` responsible for parsing commands and applying `Action`s
-/// and serializing `DriverControl` items.
-///
-/// It is effectively a composition and setup of components required to serve SMTP.
-///
-#[derive(Clone)]
-pub struct SmtpService<S> {
-    mail_service: Arc<S>,
-}
-
-impl<S> SmtpService<S>
-where
-    S: MailService + Send + Sync + 'static,
-{
-    pub fn new(mail_service: S) -> Self {
-        Self {
-            mail_service: Arc::new(mail_service),
-        }
-    }
-}
-
-impl<S> IoService for SmtpService<S>
-where
-    S: MailService + Send + Sync + 'static,
-{
-    fn handle(
-        &self,
-        io: Result<Box<dyn MayBeTls>>,
-        connection: ConnectionInfo,
-    ) -> S1Fut<'static, Result<()>> {
-        let mail_service = self.mail_service.clone();
-
-        Box::pin(async move {
-            info!("New peer connection {}", connection);
-
-            let mut io = io?;
-            let mut sess = SessionInfo::new(connection, "".to_owned());
-
-            // Add tls if needed and available
-            if !io.can_encrypt() && !io.is_encrypted() {
-                if let Some(upgrade) = mail_service.get_tls_upgrade() {
-                    let plain: Box<dyn Io> = Box::new(io);
-                    io = Box::new(TlsCapable::enabled(plain, upgrade, String::default()));
-                }
-            }
-
-            // enable STARTTLS extension if it can be used
-            if io.can_encrypt() && !io.is_encrypted() {
-                sess.extensions.enable(&extension::STARTTLS);
-            }
-
-            let mut driver = SmtpDriver::new(io);
-
-            let interpretter = mail_service.get_interpretter();
-            let mut state = SmtpState::new(mail_service);
-
-            // send connection info
-            Esmtp.apply(sess, &mut state).await;
-
-            while driver.is_open() {
-                // fetch and apply commands
-                driver.drive(&interpretter, &mut state).await?
-            }
-
-            Ok(())
-        })
-    }
-}

samotop-core/src/io/tls/mod.rs

@@ -2,6 +2,57 @@ mod notls;
 mod stream;
 mod traits;
 
+use core::panic;
+
 pub use notls::*;
 pub use stream::*;
 pub use traits::*;
+
+use crate::common::*;
+
+impl Read for Dummy {
+    fn poll_read(
+        self: Pin<&mut Self>,
+        _cx: &mut Context<'_>,
+        _buf: &mut [u8],
+    ) -> Poll<io::Result<usize>> {
+        panic!("Cannot read on dummy IO")
+    }
+}
+
+impl Write for Dummy {
+    fn poll_write(
+        self: Pin<&mut Self>,
+        _cx: &mut Context<'_>,
+        _buf: &[u8],
+    ) -> Poll<io::Result<usize>> {
+        panic!("Cannot write on dummy IO")
+    }
+
+    fn poll_flush(self: Pin<&mut Self>, _cx: &mut Context<'_>) -> Poll<io::Result<()>> {
+        panic!("Cannot flush on dummy IO")
+    }
+
+    fn poll_close(self: Pin<&mut Self>, _cx: &mut Context<'_>) -> Poll<io::Result<()>> {
+        // tolerate close
+        Poll::Ready(Ok(()))
+    }
+}
+
+impl MayBeTls for Dummy {
+    fn enable_encryption(&mut self, _upgrade: Box<dyn self::TlsUpgrade>, _name: String) {
+        panic!("Cannot enable encryption on dummy IO")
+    }
+
+    fn encrypt(self: std::pin::Pin<&mut Self>) {
+        panic!("Cannot encryptn on dummy IO")
+    }
+
+    fn can_encrypt(&self) -> bool {
+        false
+    }
+
+    fn is_encrypted(&self) -> bool {
+        false
+    }
+}

samotop-core/src/io/tls/notls.rs

 use super::{TlsProvider, TlsUpgrade};
+use crate::common::*;
 use crate::io::tls::Io;
-use crate::{
-    common::*,
-    mail::{Configuration, MailSetup},
-};
 
 #[derive(Default, Debug, Clone, Copy)]
 pub struct NoTls;
@@ -53,9 +50,3 @@ impl Write for Impossible {
         unreachable!()
     }
 }
-
-impl MailSetup for NoTls {
-    fn setup(self, config: &mut Configuration) {
-        config.tls = Box::new(self);
-    }
-}

samotop-core/src/io/tls/stream.rs

 use super::{Io, MayBeTls, TlsUpgrade};
 use crate::common::*;
+use core::panic;
 use std::fmt;
 
 pub struct TlsCapable {
@@ -56,6 +57,15 @@ impl MayBeTls for TlsCapable {
             State::Failed => false,
         }
     }
+
+    fn enable_encryption(&mut self, upgrade: Box<dyn super::TlsUpgrade>, name: String) {
+        self.state = match std::mem::replace(&mut self.state, State::Failed) {
+            State::Enabled(io, _, _) => State::Enabled(io, upgrade, name),
+            State::Done(io, _) => State::Enabled(io, upgrade, name),
+            State::Handshake(_) => panic!("currently upgrading"),
+            State::Failed => panic!("IO failed"),
+        }
+    }
 }
 impl TlsCapable {
     pub fn plaintext(io: Box<dyn Io>) -> Self {

samotop-core/src/io/tls/traits.rs

@@ -4,6 +4,7 @@ use std::ops::DerefMut;
 /// A stream implementing this trait may be able to upgrade to TLS
 /// But maybe not...
 pub trait MayBeTls: Unpin + Read + Write + Sync + Send {
+    fn enable_encryption(&mut self, upgrade: Box<dyn super::TlsUpgrade>, name: String);
     /// Initiates the TLS negotiations.
     /// The stream must then block all reads/writes until the
     /// underlying TLS handshake is done.
@@ -31,6 +32,10 @@ where
     fn is_encrypted(&self) -> bool {
         TLSIO::is_encrypted(T::deref(self))
     }
+
+    fn enable_encryption(&mut self, upgrade: Box<dyn super::TlsUpgrade>, name: String) {
+        TLSIO::enable_encryption(T::deref_mut(self), upgrade, name)
+    }
 }
 
 pub trait Io: Read + Write + Sync + Send + Unpin {}

samotop-core/src/lib.rs

@@ -28,6 +28,19 @@ pub mod common {
     pub use std::sync::Arc;
     pub use std::task::{Context, Poll};
 
+    #[derive(Debug, Copy, Clone)]
+    pub struct Dummy;
+
+    /// In the absence of random number generator produces a time based identifier
+    /// It is not reliable nor secure, RNG/PRNG should be preffered.
+    pub fn time_based_id() -> String {
+        fn nonnumber(input: char) -> bool {
+            !input.is_ascii_digit()
+        }
+        // for the lack of better unique string without extra dependencies
+        format!("{:?}", std::time::Instant::now()).replace(nonnumber, "")
+    }
+
     /// Enable async close
     /// TODO: remove after https://github.com/async-rs/async-std/issues/977
     pub trait WriteClose {
@@ -63,6 +76,8 @@ pub mod common {
         type Output = io::Result<()>;
 
         fn poll(mut self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<Self::Output> {
+            // CHECKME: sometimes, last response is not written (I guess, based on NetCat experience)
+            //ready!(Pin::new(&mut *self.writer).poll_flush(cx))?;
             Pin::new(&mut *self.writer).poll_close(cx)
         }
     }

samotop-core/src/mail/builder.rs

 use crate::{
     common::*,
-    io::tls::{NoTls, TlsProvider, TlsUpgrade},
-    mail::{
-        AddRecipientRequest, AddRecipientResult, DispatchResult, EsmtpService, MailDispatch,
-        MailGuard, MailService, MailSetup, SessionInfo, StartMailRequest, StartMailResult,
-        Transaction,
-    },
-    smtp::{Dummy, Interpret},
+    mail::{EsmtpService, MailDispatch, MailGuard, MailSetup, Service},
+    smtp::Interpret,
 };
 
-use super::ParserProvider;
-
+/// Builds MailService from components
 #[derive(Default)]
 pub struct Builder {
     config: Configuration,
 }
 
+/// Service builder configuration
 #[derive(Debug)]
 pub struct Configuration {
-    pub id: String,
-    pub tls: Box<dyn TlsProvider + Sync + Send + 'static>,
-    pub interpretter: Box<Arc<dyn Interpret + Send + Sync>>,
+    /// ID used for identifying this instance in logs
+    pub logging_id: String,
+    pub interpret: Vec<Box<dyn Interpret + Send + Sync>>,
     pub dispatch: Vec<Box<dyn MailDispatch + Sync + Send + 'static>>,
     pub guard: Vec<Box<dyn MailGuard + Sync + Send + 'static>>,
     pub esmtp: Vec<Box<dyn EsmtpService + Sync + Send + 'static>>,
 }
 
 impl Builder {
+    /// Use a given MailSetup to build a MailService.
+    ///
+    /// See MailSetup for examples.
     pub fn using(mut self, setup: impl MailSetup) -> Self {
-        trace!("Builder {} using setup {:?}", self.config.id, setup);
+        trace!(
+            "Service builder {} using setup {:?}",
+            self.config.logging_id,
+            setup
+        );
         setup.setup(&mut self.config);
         self
     }
-    pub fn into_service(self) -> impl MailService {
-        self.config
+    /// Finalize and produce the MailService.
+    pub fn build(self) -> Service {
+        Service::new(self.config)
     }
 }
 
 impl Default for Configuration {
     fn default() -> Self {
         Self {
-            id: Default::default(),
-            tls: Box::new(NoTls),
-            interpretter: Box::new(Arc::new(Dummy)),
+            logging_id: time_based_id(),
+            interpret: Default::default(),
             dispatch: Default::default(),
             guard: Default::default(),
             esmtp: Default::default(),
         }
     }
 }
-
-impl MailDispatch for Configuration {
-    fn send_mail<'a, 's, 'f>(
-        &'a self,
-        session: &'s SessionInfo,
-        mut transaction: Transaction,
-    ) -> S1Fut<'f, DispatchResult>
-    where
-        'a: 'f,
-        's: 'f,
-    {
-        debug!(
-            "Dispatch {} with {} dispatchers sending mail {:?} on session {:?}",
-            self.id,
-            self.dispatch.len(),
-            transaction,
-            session
-        );
-        let fut = async move {
-            for disp in self.dispatch.iter() {
-                trace!("Dispatch {} send_mail calling {:?}", self.id, disp);
-                transaction = disp.send_mail(session, transaction).await?;
-            }
-            Ok(transaction)
-        };
-        Box::pin(fut)
-    }
-}
-
-impl MailGuard for Configuration {
-    fn add_recipient<'a, 'f>(
-        &'a self,
-        mut request: AddRecipientRequest,
-    ) -> S2Fut<'f, AddRecipientResult>
-    where
-        'a: 'f,
-    {
-        debug!(
-            "Guard {} with {} guards adding recipient {:?}",
-            self.id,
-            self.guard.len(),
-            request
-        );
-        let fut = async move {
-            for guard in self.guard.iter() {
-                trace!("Guard {} add_recipient calling {:?}", self.id, guard);
-                match guard.add_recipient(request).await {
-                    AddRecipientResult::Inconclusive(r) => request = r,
-                    otherwise => return otherwise,
-                }
-            }
-            AddRecipientResult::Inconclusive(request)
-        };
-        Box::pin(fut)
-    }
-
-    fn start_mail<'a, 's, 'f>(
-        &'a self,
-        session: &'s SessionInfo,
-        mut request: StartMailRequest,
-    ) -> S2Fut<'f, StartMailResult>
-    where
-        'a: 'f,
-        's: 'f,
-    {
-        debug!(
-            "Guard {} with {} guards starting mail {:?}",
-            self.id,
-            self.guard.len(),
-            request
-        );
-        let fut = async move {
-            for guard in self.guard.iter() {
-                trace!("Guard {} start_mail calling {:?}", self.id, guard);
-                match guard.start_mail(session, request).await {
-                    StartMailResult::Accepted(r) => request = r,
-                    otherwise => return otherwise,
-                }
-            }
-            StartMailResult::Accepted(request)
-        };
-        Box::pin(fut)
-    }
-}
-
-impl EsmtpService for Configuration {
-    fn prepare_session(&self, session: &mut SessionInfo) {
-        debug!(
-            "Esmtp {} with {} esmtps preparing session {:?}",
-            self.id,
-            self.esmtp.len(),
-            session
-        );
-        for esmtp in self.esmtp.iter() {
-            trace!("Esmtp {} prepare_session calling {:?}", self.id, esmtp);
-            esmtp.prepare_session(session);
-        }
-    }
-}
-
-impl TlsProvider for Configuration {
-    fn get_tls_upgrade(&self) -> Option<Box<dyn TlsUpgrade>> {
-        self.tls.get_tls_upgrade()
-    }
-}
-
-impl ParserProvider for Configuration {
-    fn get_interpretter(&self) -> Box<dyn Interpret + Sync + Send> {
-        Box::new(self.interpretter.clone())
-    }
-}

samotop-core/src/mail/debug.rs

@@ -3,7 +3,9 @@
 use std::fmt;
 
 use crate::common::*;
+use crate::io::tls::MayBeTls;
 use crate::mail::*;
+use crate::smtp::SmtpState;
 //use uuid::Uuid;
 
 #[derive(Clone, Debug)]
@@ -30,8 +32,18 @@ impl MailSetup for DebugMailService {
     }
 }
 impl EsmtpService for DebugMailService {
-    fn prepare_session(&self, session: &mut SessionInfo) {
-        info!("{}: I am {}", self.id, session.service_name);
+    fn prepare_session<'a, 'i, 's, 'f>(
+        &'a self,
+        _io: &'i mut Box<dyn MayBeTls>,
+        state: &'s mut SmtpState,
+    ) -> S1Fut<'f, ()>
+    where
+        'a: 'f,
+        'i: 'f,
+        's: 'f,
+    {
+        info!("{}: I am {}", self.id, state.session.service_name);
+        Box::pin(ready(()))
     }
 }
 

samotop-core/src/mail/driver.rs

+use crate::{
+    common::*,
+    io::tls::MayBeTls,
+    smtp::{Drive, Interpret},
+};
+
+pub trait DriverProvider: fmt::Debug {
+    fn get_driver<'io>(&self, io: &'io mut (dyn DriverIo)) -> Box<dyn Drive + Sync + Send + 'io>;
+    fn get_interpretter(&self) -> Box<dyn Interpret + Sync + Send>;
+}
+impl<T> DriverProvider for Arc<T>
+where
+    T: DriverProvider,
+{
+    fn get_driver<'io>(&self, io: &'io mut (dyn DriverIo)) -> Box<dyn Drive + Sync + Send + 'io> {
+        T::get_driver(self, io)
+    }
+    fn get_interpretter(&self) -> Box<dyn Interpret + Sync + Send> {
+        T::get_interpretter(self)
+    }
+}
+
+pub trait DriverIo: MayBeTls + Read + Write + Send + Sync + Unpin {}
+
+impl<T> DriverIo for T where T: MayBeTls + Read + Write + Send + Sync + Unpin {}

samotop-core/src/mail/esmtp.rs

 use crate::common::*;
-
-use crate::mail::SessionInfo;
+use crate::io::tls::MayBeTls;
+use crate::smtp::SmtpState;
 
 /**
 The service which implements this trait delivers ESMTP extensions.
 
 ```
-# use samotop_core::smtp::*;
-# use samotop_core::mail::*;
+use samotop_core::common::S1Fut;
+use samotop_core::smtp::*;
+use samotop_core::mail::*;
+use samotop_core::io::tls::MayBeTls;
+
 /// This mail service canhabdle 8-bit MIME
 #[derive(Clone, Debug)]
-pub struct EnableEightBit<T>(T);
+pub struct EnableEightBit;
 
-impl<T> EsmtpService for EnableEightBit<T>
-where
-    T: EsmtpService,
+impl EsmtpService for EnableEightBit
 {
-    fn prepare_session(&self, session: &mut SessionInfo) {
-        self.0.prepare_session(session);
-        session
-            .extensions
-            .enable(&extension::EIGHTBITMIME);
+    fn prepare_session<'a, 'i, 's, 'f>(
+        &'a self,
+        _io: &'i mut Box<dyn MayBeTls>,
+        state: &'s mut SmtpState,
+    ) -> S1Fut<'f, ()>
+    where
+        'a: 'f,
+        'i: 'f,
+        's: 'f
+    {
+        Box::pin(async move {
+            state.session
+                .extensions
+                .enable(&extension::EIGHTBITMIME);
+        })
     }
 }
 ```
 */
 pub trait EsmtpService: fmt::Debug {
-    fn prepare_session(&self, session: &mut SessionInfo);
+    fn prepare_session<'a, 'i, 's, 'f>(
+        &'a self,
+        io: &'i mut Box<dyn MayBeTls>,
+        state: &'s mut SmtpState,
+    ) -> S1Fut<'f, ()>
+    where
+        'a: 'f,
+        'i: 'f,
+        's: 'f;
 }
 
 impl<T> EsmtpService for Arc<T>
 where
     T: EsmtpService,
 {
-    fn prepare_session(&self, session: &mut SessionInfo) {
-        T::prepare_session(self, session)
+    fn prepare_session<'a, 'i, 's, 'f>(
+        &'a self,
+        io: &'i mut Box<dyn MayBeTls>,
+        state: &'s mut SmtpState,
+    ) -> S1Fut<'f, ()>
+    where
+        'a: 'f,
+        'i: 'f,
+        's: 'f,
+    {
+        T::prepare_session(self, io, state)
     }
 }

samotop-core/src/mail/guard.rs

@@ -98,11 +98,6 @@ pub struct AddRecipientRequest {
 #[allow(clippy::large_enum_variant)]
 pub enum AddRecipientResult {
     Inconclusive(AddRecipientRequest),
-    /// The whole mail transaction failed, subsequent RCPT and DATA will fail
-    /// 421  <domain> Service not available, closing transmission channel
-    ///  (This may be a reply to any command if the service knows it must
-    ///    shut down)
-    TerminateSession(String),
     /// Failed with description that should include the ID, see `AddRecipientFailure`
     Failed(Transaction, AddRecipientFailure, String),
     /// 251  User not local; will forward to <forward-path>
@@ -113,6 +108,11 @@ pub enum AddRecipientResult {
 
 #[derive(Debug, Clone)]
 pub enum AddRecipientFailure {
+    /// The whole mail transaction failed, subsequent RCPT and DATA will fail
+    /// 421  <domain> Service not available, closing transmission channel
+    ///  (This may be a reply to any command if the service knows it must
+    ///    shut down)
+    TerminateSession,
     /// 550 Requested action not taken: mailbox unavailable (e.g., mailbox
     /// not found, no access, or command rejected for policy reasons)
     RejectedPermanently,

samotop-core/src/mail/mailservice.rs

-use crate::{io::tls::TlsProvider, mail::*};
+use crate::{io::IoService, mail::*, smtp::Interpret};
 
 pub trait MailService:
-    TlsProvider + ParserProvider + EsmtpService + MailGuard + MailDispatch
+    IoService + Interpret + DriverProvider + EsmtpService + MailGuard + MailDispatch
 {
 }
 impl<T> MailService for T where
-    T: TlsProvider + ParserProvider + EsmtpService + MailGuard + MailDispatch
+    T: IoService + Interpret + DriverProvider + EsmtpService + MailGuard + MailDispatch
 {
 }

samotop-core/src/mail/mod.rs

 mod builder;
 mod debug;
 mod dispatch;
+mod driver;
 mod esmtp;
 mod guard;
 mod mailservice;
 mod name;
 mod null;
-mod parser;
 mod recipient;
 mod rfc2033;
 mod rfc3207;
 mod rfc5321;
 mod rfc821;
+mod service;
 mod session;
 mod setup;
 mod tls;
@@ -20,18 +21,19 @@ mod transaction;
 pub use self::builder::*;
 pub use self::debug::*;
 pub use self::dispatch::*;
+pub use self::driver::*;
 pub use self::esmtp::*;
 pub use self::guard::*;
 pub use self::mailservice::*;
 pub use self::name::*;
 pub use self::null::*;
-pub use self::parser::*;
 pub use self::recipient::*;
 pub use self::rfc2033::*;
 pub use self::rfc3207::*;
 pub use self::rfc5321::*;
 pub use self::rfc5321::*;
 pub use self::rfc821::*;
+pub use self::service::*;
 pub use self::session::*;
 pub use self::setup::*;
 pub use self::tls::*;

samotop-core/src/mail/name.rs

-use super::{EsmtpService, MailSetup, SessionInfo};
+use super::{EsmtpService, MailSetup};
+use crate::common::{ready, S1Fut};
+use crate::io::tls::MayBeTls;
+use crate::smtp::SmtpState;
 
+/// MailSetup that uses the given service name for a session.
 #[derive(Debug)]
 pub struct Name {
     name: String,
@@ -12,11 +16,23 @@ impl Name {
     }
 }
 impl EsmtpService for Name {
-    fn prepare_session(&self, session: &mut SessionInfo) {
-        session.service_name = self.name.clone();
+    /// Use a given name as a service name in the session
+    fn prepare_session<'a, 'i, 's, 'f>(
+        &'a self,
+        _io: &'i mut Box<dyn MayBeTls>,
+        state: &'s mut SmtpState,
+    ) -> S1Fut<'f, ()>
+    where
+        'a: 'f,
+        'i: 'f,
+        's: 'f,
+    {
+        state.session.service_name = self.name.clone();
+        Box::pin(ready(()))
     }
 }
 impl MailSetup for Name {
+    /// Add self as an ESMTP service so it can configure service name for each session
     fn setup(self, config: &mut super::Configuration) {
         config.esmtp.insert(0, Box::new(self))
     }