serverinfoview

Sources/Shared/XMPP/LumaSaslChallengeModule.swift

@@ -0,0 +1,26 @@
+import Foundation
+import Martin
+
+/// Observes the raw SASL `<challenge/>` stanzas before `SaslModule` consumes
+/// them, so Luma can detect the XEP-0474 downgrade-protection hash (`h=`
+/// attribute in the SCRAM server-first message) regardless of which SCRAM
+/// mechanism implementation actually runs the exchange. Registered before
+/// `SaslModule` in the module list.
+final class LumaSaslChallengeModule: XmppModuleBase, XmppModule {
+    static let ID = "lumaSaslChallenge"
+    static let saslXMLNS = "urn:ietf:params:xml:ns:xmpp-sasl"
+
+    let criteria = Criteria.name("challenge", xmlns: LumaSaslChallengeModule.saslXMLNS)
+    let features: [String] = []
+
+    private let onChallenge: (String) -> Void
+
+    init(onChallenge: @escaping (String) -> Void) {
+        self.onChallenge = onChallenge
+        super.init()
+    }
+
+    func process(stanza: Stanza) throws {
+        onChallenge(stanza.element.value ?? "")
+    }
+}