//! Simple SMTP-to-Telegram gateway. Can parse email and send them as telegram
//! messages to specified chats, generally you specify which email address is
//! available in configuration, everything else is sent to default address.
mod mail;
mod telegram;
mod utils;
#[cfg(test)]
mod tests;
use crate::mail::MailServer;
use smol::fs::metadata;
use just_getopt::{
OptFlags,
OptSpecs,
OptValue,
};
use stacked_errors::{
Result,
StackableErr,
bail,
};
use std::{
io::Cursor,
os::unix::fs::PermissionsExt,
path::Path,
};
fn main () -> Result<()> {
smol::block_on(async {
let specs = OptSpecs::new()
.option("help", "h", OptValue::None)
.option("help", "help", OptValue::None)
.option("config", "c", OptValue::Required)
.option("config", "config", OptValue::Required)
.flag(OptFlags::OptionsEverywhere);
let mut args = std::env::args();
args.next();
let parsed = specs.getopt(args);
for u in &parsed.unknown {
println!("Unknown option: {u}");
}
if !(parsed.unknown.is_empty()) || parsed.options_first("help").is_some() {
println!("SMTP2TG v{}, (C) 2024 - 2025\n\n\
\t-h|--help\tDisplay this help\n\
\t-c|--config …\tSet configuration file location.",
env!("CARGO_PKG_VERSION"));
return Ok(());
};
let config_file = Path::new(if let Some(path) = parsed.options_value_last("config") {
&path[..]
} else {
"smtp2tg.toml"
});
if !config_file.exists() {
bail!("can't read configuration from {config_file:?}");
};
{
let meta = metadata(config_file).await.stack()?;
if (!0o100600 & meta.permissions().mode()) > 0 {
bail!("other users can read or write config file {config_file:?}\n\
File permissions: {:o}", meta.permissions().mode());
}
}
let settings: config::Config = config::Config::builder()
.set_default("fields", vec!["date", "from", "subject"]).stack()?
.set_default("hostname", "smtp.2.tg").stack()?
.set_default("listen_on", "0.0.0.0:1025").stack()?
.set_default("unknown", "relay").stack()?
.set_default("domains", vec!["localhost", hostname::get().stack()?.to_str().expect("Failed to get current hostname")]).stack()?
.add_source(config::File::from(config_file))
.build()
.with_context(|| format!("[{config_file:?}] there was an error reading config\n\
\tplease consult \"smtp2tg.toml.example\" for details"))?;
let listen_on = settings.get_string("listen_on").stack()?;
let server_name = settings.get_string("hostname").stack()?;
let core = MailServer::new(settings)?;
let mut server = mailin_embedded::Server::new(core);
server.with_name(server_name)
.with_ssl(mailin_embedded::SslConfig::None).unwrap()
.with_addr(listen_on).unwrap();
server.serve().unwrap();
Ok(())
})
}