feat(tls): add SNI to SslDigest for HTTP filter access

pingora-core/src/protocols/tls/boringssl_openssl/stream.rs

@@ -209,7 +209,11 @@ impl SslDigest {
             None => (Vec::new(), None, None),
         };
 
-        SslDigest::new(cipher, ssl.version_str(), org, sn, cert_digest)
+        let sni = ssl
+            .servername(ssl::NameType::HOST_NAME)
+            .map(ToOwned::to_owned);
+
+        SslDigest::new(cipher, ssl.version_str(), org, sn, cert_digest, sni)
     }
 }
 

pingora-core/src/protocols/tls/digest.rs

@@ -31,6 +31,8 @@ pub struct SslDigest {
     pub serial_number: Option<String>,
     /// The digest of the peer's certificate
     pub cert_digest: Vec<u8>,
+    /// The SNI used during the TLS handshake
+    pub sni: Option<String>,
     /// The user-defined TLS data
     pub extension: SslDigestExtension,
 }
@@ -43,6 +45,7 @@ impl SslDigest {
         organization: Option<String>,
         serial_number: Option<String>,
         cert_digest: Vec<u8>,
+        sni: Option<String>,
     ) -> Self
     where
         S: Into<Cow<'static, str>>,
@@ -53,6 +56,7 @@ impl SslDigest {
             organization,
             serial_number,
             cert_digest,
+            sni,
             extension: SslDigestExtension::default(),
         }
     }

pingora-core/src/protocols/tls/rustls/stream.rs

@@ -390,7 +390,10 @@ impl SslDigest {
             .map(|(organization, serial)| (organization, Some(serial)))
             .unwrap_or_default();
 
-        SslDigest::new(cipher, version, organization, serial_number, cert_digest)
+        // SNI extraction not yet implemented for rustls
+        let sni = None;
+
+        SslDigest::new(cipher, version, organization, serial_number, cert_digest, sni)
     }
 }
 

pingora-core/src/protocols/tls/s2n/stream.rs

@@ -307,12 +307,16 @@ impl SslDigest {
             }
         }
 
+        // SNI extraction not yet implemented for s2n
+        let sni = None;
+
         SslDigest::new(
             cipher,
             version,
             organization,
             serial_number,
             cert_digest.unwrap_or_default(),
+            sni,
         )
     }
 }