add mail_starttls parameter, default off

local mail connections are much preferred for this service, and those
needn't be encrypted.

2 files changed, 9 insertions, 1 deletions

diff --git a/src/lib.rs b/src/lib.rs
index ba654c0..29f3e08 100644
--- a/src/lib.rs
+++ b/src/lib.rs
@@ -71,6 +71,8 @@ struct Config {
     mail_from: Mailbox,
     mail_host: Option<String>,
     mail_port: Option<u16>,
+    #[serde(default)]
+    mail_starttls: bool,
 
     #[serde(default)]
     invite_only: bool,
@@ -250,6 +252,7 @@ pub async fn build(
             config.mail_from.clone(),
             config.mail_host.as_deref().unwrap_or("localhost"),
             config.mail_port.unwrap_or(25),
+            config.mail_starttls,
             config.location.clone(),
         )
         .context("setting up mail notifications")?,
diff --git a/src/mailer.rs b/src/mailer.rs
index 18f89b0..7f7ad9f 100644
--- a/src/mailer.rs
+++ b/src/mailer.rs
@@ -21,6 +21,7 @@ impl Mailer {
         from: Mailbox,
         host: &str,
         port: u16,
+        starttls: bool,
         verify_base: Absolute<'static>,
     ) -> anyhow::Result<Self> {
         Ok(Mailer {
@@ -28,7 +29,11 @@ impl Mailer {
             verify_base,
             transport: AsyncSmtpTransport::<Tokio1Executor>::builder_dangerous(host)
                 .port(port)
-                .tls(Tls::Opportunistic(TlsParameters::new(host.to_string())?))
+                .tls(if starttls {
+                    Tls::Required(TlsParameters::new(host.to_string())?)
+                } else {
+                    Tls::None
+                })
                 .timeout(Some(Duration::from_secs(5)))
                 .build(),
         })