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use bufstream::BufStream;
use nom::ErrorKind as NomErrorKind;
use smtp::authentication::{Credentials, Mechanism};
use smtp::client::net::{ClientTlsParameters, Connector, NetworkStream, Timeout};
use smtp::commands::*;
use smtp::error::{Error, SmtpResult};
use smtp::response::Response;
use std::fmt::{Debug, Display};
use std::io::{self, BufRead, BufReader, Read, Write};
use std::net::ToSocketAddrs;
use std::string::String;
use std::time::Duration;
pub mod mock;
pub mod net;
#[derive(Default, Clone, Copy, Debug)]
#[cfg_attr(feature = "serde-impls", derive(Serialize, Deserialize))]
pub struct ClientCodec {
escape_count: u8,
}
impl ClientCodec {
pub fn new() -> Self {
ClientCodec::default()
}
}
impl ClientCodec {
fn encode(&mut self, frame: &[u8], buf: &mut Vec<u8>) -> Result<(), Error> {
match frame.len() {
0 => {
match self.escape_count {
0 => buf.write_all(b"\r\n.\r\n")?,
1 => buf.write_all(b"\n.\r\n")?,
2 => buf.write_all(b".\r\n")?,
_ => unreachable!(),
}
self.escape_count = 0;
Ok(())
}
_ => {
let mut start = 0;
for (idx, byte) in frame.iter().enumerate() {
match self.escape_count {
0 => self.escape_count = if *byte == b'\r' { 1 } else { 0 },
1 => self.escape_count = if *byte == b'\n' { 2 } else { 0 },
2 => self.escape_count = if *byte == b'.' { 3 } else { 0 },
_ => unreachable!(),
}
if self.escape_count == 3 {
self.escape_count = 0;
buf.write_all(&frame[start..idx])?;
buf.write_all(b".")?;
start = idx;
}
}
buf.write_all(&frame[start..])?;
Ok(())
}
}
}
}
fn escape_crlf(string: &str) -> String {
string.replace("\r\n", "<CRLF>")
}
#[derive(Debug, Default)]
pub struct InnerClient<S: Write + Read = NetworkStream> {
stream: Option<BufStream<S>>,
}
macro_rules! return_err (
($err: expr, $client: ident) => ({
return Err(From::from($err))
})
);
#[cfg_attr(feature = "cargo-clippy", allow(clippy::new_without_default_derive))]
impl<S: Write + Read> InnerClient<S> {
pub fn new() -> InnerClient<S> {
InnerClient { stream: None }
}
}
impl<S: Connector + Write + Read + Timeout + Debug> InnerClient<S> {
pub fn close(&mut self) {
let _ = self.command(QuitCommand);
self.stream = None;
}
pub fn set_stream(&mut self, stream: S) {
self.stream = Some(BufStream::new(stream));
}
pub fn upgrade_tls_stream(&mut self, tls_parameters: &ClientTlsParameters) -> io::Result<()> {
match self.stream {
Some(ref mut stream) => stream.get_mut().upgrade_tls(tls_parameters),
None => Ok(()),
}
}
pub fn is_encrypted(&self) -> bool {
match self.stream {
Some(ref stream) => stream.get_ref().is_encrypted(),
None => false,
}
}
pub fn set_timeout(&mut self, duration: Option<Duration>) -> io::Result<()> {
match self.stream {
Some(ref mut stream) => {
stream.get_mut().set_read_timeout(duration)?;
stream.get_mut().set_write_timeout(duration)?;
Ok(())
}
None => Ok(()),
}
}
pub fn connect<A: ToSocketAddrs>(
&mut self,
addr: &A,
tls_parameters: Option<&ClientTlsParameters>,
) -> SmtpResult {
if self.stream.is_some() {
return_err!("The connection is already established", self);
}
let mut addresses = addr.to_socket_addrs()?;
let server_addr = match addresses.next() {
Some(addr) => addr,
None => return_err!("Could not resolve hostname", self),
};
debug!("connecting to {}", server_addr);
self.set_stream(Connector::connect(&server_addr, tls_parameters)?);
self.read_response()
}
#[cfg_attr(feature = "cargo-clippy", allow(clippy::wrong_self_convention))]
pub fn is_connected(&mut self) -> bool {
self.stream.is_some() && self.command(NoopCommand).is_ok()
}
pub fn auth(&mut self, mechanism: Mechanism, credentials: &Credentials) -> SmtpResult {
let mut challenges = 10;
let mut response = self.command(AuthCommand::new(mechanism, credentials.clone(), None)?)?;
while challenges > 0 && response.has_code(334) {
challenges -= 1;
response = self.command(AuthCommand::new_from_response(
mechanism,
credentials.clone(),
&response,
)?)?;
}
if challenges == 0 {
Err(Error::ResponseParsing("Unexpected number of challenges"))
} else {
Ok(response)
}
}
pub fn message(&mut self, message: Box<dyn Read>) -> SmtpResult {
let mut out_buf: Vec<u8> = vec![];
let mut codec = ClientCodec::new();
let mut message_reader = BufReader::new(message);
loop {
out_buf.clear();
let consumed = match message_reader.fill_buf() {
Ok(bytes) => {
codec.encode(bytes, &mut out_buf)?;
bytes.len()
}
Err(ref err) => panic!("Failed with: {}", err),
};
message_reader.consume(consumed);
if consumed == 0 {
break;
}
self.write(out_buf.as_slice())?;
}
self.write(b"\r\n.\r\n")?;
self.read_response()
}
pub fn command<C: Display>(&mut self, command: C) -> SmtpResult {
self.write(command.to_string().as_bytes())?;
self.read_response()
}
fn write(&mut self, string: &[u8]) -> Result<(), Error> {
if self.stream.is_none() {
return Err(From::from("Connection closed"));
}
self.stream.as_mut().unwrap().write_all(string)?;
self.stream.as_mut().unwrap().flush()?;
debug!(
"Wrote: {}",
escape_crlf(String::from_utf8_lossy(string).as_ref())
);
Ok(())
}
fn read_response(&mut self) -> SmtpResult {
let mut raw_response = String::new();
let mut response = raw_response.parse::<Response>();
while response.is_err() {
if response.as_ref().err().unwrap() != &NomErrorKind::Complete {
break;
}
let read_count = self.stream.as_mut().unwrap().read_line(&mut raw_response)?;
if read_count == 0 {
break;
}
response = raw_response.parse::<Response>();
}
debug!("Read: {}", escape_crlf(raw_response.as_ref()));
let final_response = response?;
if final_response.is_positive() {
Ok(final_response)
} else {
Err(From::from(final_response))
}
}
}
#[cfg(test)]
mod test {
use super::{escape_crlf, ClientCodec};
#[test]
fn test_codec() {
let mut codec = ClientCodec::new();
let mut buf: Vec<u8> = vec![];
assert!(codec.encode(b"test\r\n", &mut buf).is_ok());
assert!(codec.encode(b".\r\n", &mut buf).is_ok());
assert!(codec.encode(b"\r\ntest", &mut buf).is_ok());
assert!(codec.encode(b"te\r\n.\r\nst", &mut buf).is_ok());
assert!(codec.encode(b"test", &mut buf).is_ok());
assert!(codec.encode(b"test.", &mut buf).is_ok());
assert!(codec.encode(b"test\n", &mut buf).is_ok());
assert!(codec.encode(b".test\n", &mut buf).is_ok());
assert!(codec.encode(b"test", &mut buf).is_ok());
assert_eq!(
String::from_utf8(buf).unwrap(),
"test\r\n..\r\n\r\ntestte\r\n..\r\nsttesttest.test\n.test\ntest"
);
}
#[test]
fn test_escape_crlf() {
assert_eq!(escape_crlf("\r\n"), "<CRLF>");
assert_eq!(escape_crlf("EHLO my_name\r\n"), "EHLO my_name<CRLF>");
assert_eq!(
escape_crlf("EHLO my_name\r\nSIZE 42\r\n"),
"EHLO my_name<CRLF>SIZE 42<CRLF>"
);
}
}