filip/Stalwart
1
0
Fork 0
Code Issues Pull Requests Actions 1 Packages Projects Releases Wiki Activity

Refuse loopback SMTP delivery (closes #1377)

Browse Source
This commit is contained in:
mdecimus
2025-04-16 13:16:18 +02:00
parent 3bd255eb09
commit ce27cecded
1 changed files with 16 additions and 2 deletions
Download Patch File Download Diff File Expand all files Collapse all files

18
crates/smtp/src/outbound/lookup.rs
View File

@@ -114,6 +114,7 @@ impl DnsLookup for Server {
} }
} }
#[allow(unused_mut)]
async fn resolve_host( async fn resolve_host(
&self, &self,
remote_host: &NextHop<'_>, remote_host: &NextHop<'_>,
@@ -121,7 +122,7 @@ impl DnsLookup for Server {
max_multihomed: usize, max_multihomed: usize,
session_id: u64, session_id: u64,
) -> Result<IpLookupResult, Status<(), Error>> { ) -> Result<IpLookupResult, Status<(), Error>> {
let remote_ips = self let mut remote_ips = self
.ip_lookup( .ip_lookup(
remote_host.fqdn_hostname().as_ref(), remote_host.fqdn_hostname().as_ref(),
self.eval_if(&self.core.smtp.queue.ip_strategy, envelope, session_id) self.eval_if(&self.core.smtp.queue.ip_strategy, envelope, session_id)
@@ -139,7 +140,7 @@ impl DnsLookup for Server {
.. ..
} }
) { ) {
Status::PermanentFailure(Error::DnsError("No MX record found.".into())) Status::PermanentFailure(Error::DnsError("no MX record found.".into()))
} else { } else {
Status::PermanentFailure(Error::ConnectionError(ErrorDetails { Status::PermanentFailure(Error::ConnectionError(ErrorDetails {
entity: remote_host.hostname().into(), entity: remote_host.hostname().into(),
@@ -155,6 +156,19 @@ impl DnsLookup for Server {
})?; })?;
if !remote_ips.is_empty() { if !remote_ips.is_empty() {
#[cfg(not(feature = "test_mode"))]
if remote_ips.iter().any(|ip| ip.is_loopback()) {
remote_ips.retain(|ip| !ip.is_loopback());
if remote_ips.is_empty() {
return Err(Status::PermanentFailure(Error::ConnectionError(
ErrorDetails {
entity: remote_host.hostname().into(),
details: "host resolves loopback address".into(),
},
)));
}
}
let mut result = IpLookupResult { let mut result = IpLookupResult {
source_ipv4: None, source_ipv4: None,
source_ipv6: None, source_ipv6: None,