v0.1.0

.github/FUNDING.yml

@@ -0,0 +1,13 @@
+# These are supported funding model platforms
+
+github: stalwartlabs
+patreon: # Replace with a single Patreon username
+open_collective: # Replace with a single Open Collective username
+ko_fi: # Replace with a single Ko-fi username
+tidelift: # Replace with a single Tidelift platform-name/package-name e.g., npm/babel
+community_bridge: # Replace with a single Community Bridge project-name e.g., cloud-foundry
+liberapay: # Replace with a single Liberapay username
+issuehunt: # Replace with a single IssueHunt username
+otechie: # Replace with a single Otechie username
+lfx_crowdfunding: # Replace with a single LFX Crowdfunding project-name e.g., cloud-foundry
+custom: # Replace with up to 4 custom sponsorship URLs e.g., ['link1', 'link2']

.github/workflows/rust.yml

@@ -0,0 +1,22 @@
+name: "CI"
+
+on:
+  push:
+    branches: [ main ]
+  pull_request:
+    branches: [ main ]
+
+env:
+  CARGO_TERM_COLOR: always
+
+jobs:
+  build:
+
+    runs-on: ubuntu-latest
+
+    steps:
+    - uses: actions/checkout@v2
+    - name: Build
+      run: cargo build --verbose
+    - name: Run tests
+      run: cargo test --verbose

Cargo.toml

@@ -1,5 +1,13 @@
 [package]
 name = "smtp-proto"
+description = "SMTP protocol parser"
+authors = [ "Stalwart Labs <hello@stalw.art>"]
+repository = "https://github.com/stalwartlabs/smtp-proto"
+homepage = "https://github.com/stalwartlabs/smtp-proto"
+license = "AGPL-3.0-only"
+keywords = ["smtp", "lmtp", "protocol", "parser"]
+categories = ["email", "parser-implementations"]
+readme = "README.md"
 version = "0.1.0"
 edition = "2021"
 

README.md

@@ -1,2 +1,37 @@
 # smtp-proto
-SMTP Protocol
+
+[![crates.io](https://img.shields.io/crates/v/smtp-proto)](https://crates.io/crates/smtp-proto)
+[![build](https://github.com/stalwartlabs/sieve/actions/workflows/rust.yml/badge.svg)](https://github.com/stalwartlabs/sieve/actions/workflows/rust.yml)
+[![docs.rs](https://img.shields.io/docsrs/smtp-proto)](https://docs.rs/smtp-proto)
+[![License: AGPL v3](https://img.shields.io/badge/License-AGPL_v3-blue.svg)](https://www.gnu.org/licenses/agpl-3.0)
+
+_smtp-proto_ is a fast SMTP/LMTP parser for Rust that supports all [registered SMTP service extensions](https://www.iana.org/assignments/mail-parameters/mail-parameters.xhtml).
+The library is part of Stalwart SMTP and LMTP servers. It is not yet documented so if you need help using the library please start a discussion.
+
+
+## Testing & Fuzzing
+
+To run the testsuite:
+
+```bash
+ $ cargo test
+```
+
+To fuzz the library with `cargo-fuzz`:
+
+```bash
+ $ cargo +nightly fuzz run smtp_proto
+```
+
+## License
+
+Licensed under the terms of the [GNU Affero General Public License](https://www.gnu.org/licenses/agpl-3.0.en.html) as published by
+the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
+See [LICENSE](LICENSE) for more details.
+
+You can be released from the requirements of the AGPLv3 license by purchasing
+a commercial license. Please contact licensing@stalw.art for more details.
+  
+## Copyright
+
+Copyright (C) 2020-2023, Stalwart Labs Ltd.

src/lib.rs

@@ -1,3 +1,64 @@
+/*
+ * Copyright (c) 2020-2023, Stalwart Labs Ltd.
+ *
+ * This file is part of the Stalwart SMTP protocol parser.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ * in the LICENSE file at the top-level directory of this distribution.
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * You can be released from the requirements of the AGPLv3 license by
+ * purchasing a commercial license. Please contact licensing@stalw.art
+ * for more details.
+*/
+
+//! # smtp-proto
+//!
+//! [![crates.io](https://img.shields.io/crates/v/smtp-proto)](https://crates.io/crates/smtp-proto)
+//! [![build](https://github.com/stalwartlabs/sieve/actions/workflows/rust.yml/badge.svg)](https://github.com/stalwartlabs/sieve/actions/workflows/rust.yml)
+//! [![docs.rs](https://img.shields.io/docsrs/smtp-proto)](https://docs.rs/smtp-proto)
+//! [![License: AGPL v3](https://img.shields.io/badge/License-AGPL_v3-blue.svg)](https://www.gnu.org/licenses/agpl-3.0)
+//!
+//! _smtp-proto_ is a fast SMTP/LMTP parser for Rust that supports all [registered SMTP service extensions](https://www.iana.org/assignments/mail-parameters/mail-parameters.xhtml).
+//! The library is part of Stalwart SMTP and LMTP servers. It is not yet documented so if you need help using the library please start a discussion.
+//!
+//!
+//! ## Testing & Fuzzing
+//!
+//! To run the testsuite:
+//!
+//! ```bash
+//!  $ cargo test
+//! ```
+//!
+//! To fuzz the library with `cargo-fuzz`:
+//!
+//! ```bash
+//!  $ cargo +nightly fuzz run smtp_proto
+//! ```
+//!
+//! ## License
+//!
+//! Licensed under the terms of the [GNU Affero General Public License](https://www.gnu.org/licenses/agpl-3.0.en.html) as published by
+//! the Free Software Foundation, either version 3 of the License, or (at your option) any later version.
+//! See [LICENSE](LICENSE) for more details.
+//!
+//! You can be released from the requirements of the AGPLv3 license by purchasing
+//! a commercial license. Please contact licensing@stalw.art for more details.
+//!   
+//! ## Copyright
+//!
+//! Copyright (C) 2020-2023, Stalwart Labs Ltd.
+
 use std::fmt::Display;
 
 pub mod request;

src/request/mod.rs

@@ -1,3 +1,26 @@
+/*
+ * Copyright (c) 2020-2023, Stalwart Labs Ltd.
+ *
+ * This file is part of the Stalwart SMTP protocol parser.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ * in the LICENSE file at the top-level directory of this distribution.
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * You can be released from the requirements of the AGPLv3 license by
+ * purchasing a commercial license. Please contact licensing@stalw.art
+ * for more details.
+*/
+
 pub mod parser;
 pub mod receiver;
 

src/request/parser.rs

@@ -1,3 +1,26 @@
+/*
+ * Copyright (c) 2020-2023, Stalwart Labs Ltd.
+ *
+ * This file is part of the Stalwart SMTP protocol parser.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ * in the LICENSE file at the top-level directory of this distribution.
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * You can be released from the requirements of the AGPLv3 license by
+ * purchasing a commercial license. Please contact licensing@stalw.art
+ * for more details.
+*/
+
 use std::slice::Iter;
 
 use crate::*;
@@ -7,6 +30,9 @@ use super::*;
 #[derive(Default)]
 pub struct RequestParser {}
 
+const MAX_ADDRESS_LEN: usize = 256;
+const MAX_DOMAIN_LEN: usize = 255;
+
 impl Request<String> {
     pub fn parse(bytes: &mut Iter<'_, u8>) -> Result<Request<String>, Error> {
         let mut parser = Rfc5321Parser::new(bytes);
@@ -70,7 +96,7 @@ impl Request<String> {
                 if parser.stop_char != LF {
                     let host = parser.text()?;
                     parser.seek_lf()?;
-                    if !host.is_empty() {
+                    if (1..=MAX_DOMAIN_LEN).contains(&host.len()) {
                         return Ok(Request::Ehlo { host });
                     }
                 }
@@ -136,7 +162,7 @@ impl Request<String> {
                 if parser.stop_char != LF {
                     let value = parser.string()?;
                     parser.seek_lf()?;
-                    if !value.is_empty() {
+                    if (1..=MAX_ADDRESS_LEN).contains(&value.len()) {
                         return Ok(Request::Expn { value });
                     }
                 }
@@ -163,7 +189,7 @@ impl Request<String> {
                 if parser.stop_char != LF {
                     let host = parser.text()?;
                     parser.seek_lf()?;
-                    if !host.is_empty() {
+                    if (1..=MAX_DOMAIN_LEN).contains(&host.len()) {
                         return Ok(Request::Lhlo { host });
                     }
                 }
@@ -179,7 +205,7 @@ impl Request<String> {
                 if parser.stop_char != LF {
                     let value = parser.string()?;
                     parser.seek_lf()?;
-                    if !value.is_empty() {
+                    if (1..=MAX_ADDRESS_LEN).contains(&value.len()) {
                         return Ok(Request::Vrfy { value });
                     }
                 }
@@ -272,7 +298,7 @@ impl Request<String> {
                 if parser.stop_char != LF {
                     let host = parser.text()?;
                     parser.seek_lf()?;
-                    if !host.is_empty() {
+                    if (1..=MAX_DOMAIN_LEN).contains(&host.len()) {
                         return Ok(Request::Helo { host });
                     }
                 }
@@ -423,11 +449,13 @@ impl<'x, 'y> Rfc5321Parser<'x, 'y> {
                     self.stop_char = ch;
                     let value = value.into_string();
                     let len = value.chars().count();
-                    return Ok(if len == 0 || len < 255 && at_count == 1 && lp_len > 0 {
+                    return Ok(
+                        if len == 0 || len <= MAX_ADDRESS_LEN && at_count == 1 && lp_len > 0 {
                             value.into()
                         } else {
                             None
-                    });
+                        },
+                    );
                 }
                 b'\r' => (),
                 b':' if !in_quote && matches!(value.first(), Some(b'@')) => {
@@ -442,22 +470,26 @@ impl<'x, 'y> Rfc5321Parser<'x, 'y> {
                         self.stop_char = b' ';
                         let value = value.into_string();
                         let len = value.chars().count();
-                        return Ok(if len == 0 || len < 255 && at_count == 1 && lp_len > 0 {
+                        return Ok(
+                            if len == 0 || len <= MAX_ADDRESS_LEN && at_count == 1 && lp_len > 0 {
                                 value.into()
                             } else {
                                 None
-                        });
+                            },
+                        );
                     }
                 }
                 b'\n' => {
                     self.stop_char = b'\n';
                     let value = value.into_string();
                     let len = value.chars().count();
-                    return Ok(if len == 0 || len < 255 && at_count == 1 && lp_len > 0 {
+                    return Ok(
+                        if len == 0 || len <= MAX_ADDRESS_LEN && at_count == 1 && lp_len > 0 {
                             value.into()
                         } else {
                             None
-                    });
+                        },
+                    );
                 }
                 b'\"' if !in_quote || last_ch != b'\\' => {
                     in_quote = !in_quote;
@@ -937,7 +969,9 @@ impl<'x, 'y> Rfc5321Parser<'x, 'y> {
                 }
                 AUTH_ if self.stop_char == b'=' => {
                     let mailbox = self.xtext()?;
-                    if !mailbox.is_empty() && self.stop_char.is_ascii_whitespace() {
+                    if (1..=MAX_ADDRESS_LEN).contains(&mailbox.len())
+                        && self.stop_char.is_ascii_whitespace()
+                    {
                         params.auth = mailbox.into();
                     } else {
                         self.seek_lf()?;
@@ -1039,7 +1073,9 @@ impl<'x, 'y> Rfc5321Parser<'x, 'y> {
                         return Err(Error::InvalidParameter { param: "ORCPT" });
                     }
                     let addr = self.xtext()?;
-                    if self.stop_char.is_ascii_whitespace() && (1..=500).contains(&addr.len()) {
+                    if self.stop_char.is_ascii_whitespace()
+                        && (1..=MAX_ADDRESS_LEN).contains(&addr.len())
+                    {
                         params.orcpt = addr.into();
                     } else {
                         self.seek_lf()?;
@@ -2081,12 +2117,11 @@ mod tests {
             let (request, parsed_request): (&str, Result<Request<String>, Error>) = item;
 
             for extra in ["\n", "\r\n", " \n", " \r\n"] {
-                let request = format!("{}{}", request, extra);
+                let request = format!("{request}{extra}");
                 assert_eq!(
                     parsed_request,
                     Request::parse(&mut request.as_bytes().iter()),
-                    "failed for {:?}",
+                    "failed for {request:?}"
-                    request
                 );
             }
         }

src/request/receiver.rs

@@ -1,3 +1,26 @@
+/*
+ * Copyright (c) 2020-2023, Stalwart Labs Ltd.
+ *
+ * This file is part of the Stalwart SMTP protocol parser.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ * in the LICENSE file at the top-level directory of this distribution.
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * You can be released from the requirements of the AGPLv3 license by
+ * purchasing a commercial license. Please contact licensing@stalw.art
+ * for more details.
+*/
+
 use std::slice::Iter;
 
 use crate::{Error, Request};
@@ -247,7 +270,7 @@ mod tests {
                     continue 'outer;
                 }
             }
-            panic!("Failed for {:?}", data);
+            panic!("Failed for {data:?}");
         }
     }
 
@@ -295,7 +318,7 @@ mod tests {
                         Err(Error::NeedsMoreData { .. }) => {
                             break;
                         }
-                        err => panic!("Unexpected error {:?}", err),
+                        err => panic!("Unexpected error {err:?}"),
                     }
                 }
             }

src/response/generate.rs

@@ -1,3 +1,26 @@
+/*
+ * Copyright (c) 2020-2023, Stalwart Labs Ltd.
+ *
+ * This file is part of the Stalwart SMTP protocol parser.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ * in the LICENSE file at the top-level directory of this distribution.
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * You can be released from the requirements of the AGPLv3 license by
+ * purchasing a commercial license. Please contact licensing@stalw.art
+ * for more details.
+*/
+
 use std::{
     fmt::Display,
     io::{self, Write},
@@ -39,7 +62,7 @@ impl<T: Display> EhloResponse<T> {
                     while mechanisms != 0 {
                         let item = 1 << (63 - mechanisms.leading_zeros());
                         mechanisms ^= item;
-                        write!(writer, " {}", (item as u64).to_mechanism())?;
+                        write!(writer, " {}", item.to_mechanism())?;
                     }
                     writer.write_all(b"\r\n")
                 }
@@ -79,7 +102,7 @@ impl<T: Display> EhloResponse<T> {
                 EXT_MTRK => write!(writer, "MTRK\r\n"),
                 EXT_NO_SOLICITING => {
                     if let Some(keywords) = &self.no_soliciting {
-                        write!(writer, "NO-SOLICITING {}\r\n", keywords)
+                        write!(writer, "NO-SOLICITING {keywords}\r\n")
                     } else {
                         write!(writer, "NO-SOLICITING\r\n")
                     }

src/response/mod.rs

@@ -1,3 +1,26 @@
+/*
+ * Copyright (c) 2020-2023, Stalwart Labs Ltd.
+ *
+ * This file is part of the Stalwart SMTP protocol parser.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ * in the LICENSE file at the top-level directory of this distribution.
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * You can be released from the requirements of the AGPLv3 license by
+ * purchasing a commercial license. Please contact licensing@stalw.art
+ * for more details.
+*/
+
 use std::fmt::Display;
 
 use crate::{EhloResponse, Response};

src/response/parser.rs

@@ -1,3 +1,26 @@
+/*
+ * Copyright (c) 2020-2023, Stalwart Labs Ltd.
+ *
+ * This file is part of the Stalwart SMTP protocol parser.
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as
+ * published by the Free Software Foundation, either version 3 of
+ * the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU Affero General Public License for more details.
+ * in the LICENSE file at the top-level directory of this distribution.
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ * You can be released from the requirements of the AGPLv3 license by
+ * purchasing a commercial license. Please contact licensing@stalw.art
+ * for more details.
+*/
+
 use std::slice::Iter;
 
 use crate::{request::parser::Rfc5321Parser, *};
@@ -480,8 +503,7 @@ mod tests {
                 assert_eq!(
                     parsed_response,
                     EhloResponse::parse(&mut response.as_bytes().iter()),
-                    "failed for {:?}",
+                    "failed for {response:?}",
-                    response
                 );
             }
         }
@@ -624,8 +646,7 @@ mod tests {
                 ResponseReceiver::default()
                     .parse(&mut response.as_bytes().iter())
                     .unwrap(),
-                "failed for {:?}",
+                "failed for {response:?}",
-                response
             );
             all_responses.extend_from_slice(response.as_bytes());
             all_parsed_responses.push(parsed_response);
@@ -643,15 +664,14 @@ mod tests {
                             assert_eq!(
                                 parsed_response.next(),
                                 Some(response),
-                                "chunk size {}",
+                                "chunk size {chunk_size}",
-                                chunk_size
                             );
                             receiver.reset();
                         }
                         Err(Error::NeedsMoreData { .. }) => {
                             break;
                         }
-                        err => panic!("Unexpected error {:?} for chunk size {}", err, chunk_size),
+                        err => panic!("Unexpected error {err:?} for chunk size {chunk_size}"),
                     }
                 }
             }