spf: add basic support for the exists mechanism

2026-09-09 03:52:13 +00:00 · 2024-10-12 08:00:15 -07:00
parent 487a45c9ff
commit 5853970c0f
1 changed files with 12 additions and 1 deletions
@@ -234,7 +234,18 @@ impl Directive {
                    }
                }
            }
-            _ => todo!("evaluate directive {self:?}"),
+            Mechanism::Exists { domain } => {
+                let domain = cx.domain(Some(domain))?;
+                match resolver.lookup_ip(&domain).await {
+                    Ok(ips) => ips.iter().any(|ip| ip.is_ipv4()),
+                    Err(err) => {
+                        return Err(SpfResult {
+                            disposition: SpfDisposition::TempError,
+                            context: format!("error looking up IP for {domain}: {err}"),
+                        })
+                    }
+                }
+            }
        };

        Ok(match matched {