LookupServer: Split mDNS flags into separate field

6 files changed, 31 insertions, 13 deletions

diff --git a/Userland/Services/LookupServer/DNSAnswer.cpp b/Userland/Services/LookupServer/DNSAnswer.cpp
index d089d04732..167361ac3e 100644
--- a/Userland/Services/LookupServer/DNSAnswer.cpp
+++ b/Userland/Services/LookupServer/DNSAnswer.cpp
@@ -9,12 +9,13 @@
 
 namespace LookupServer {
 
-DNSAnswer::DNSAnswer(const DNSName& name, u16 type, u16 class_code, u32 ttl, const String& record_data)
+DNSAnswer::DNSAnswer(const DNSName& name, u16 type, u16 class_code, u32 ttl, const String& record_data, bool mdns_cache_flush)
     : m_name(name)
     , m_type(type)
     , m_class_code(class_code)
     , m_ttl(ttl)
     , m_record_data(record_data)
+    , m_mdns_cache_flush(mdns_cache_flush)
 {
     auto now = time(nullptr);
     m_expiration_time = now + m_ttl;
diff --git a/Userland/Services/LookupServer/DNSAnswer.h b/Userland/Services/LookupServer/DNSAnswer.h
index c73a9f6a1f..d5dffe597c 100644
--- a/Userland/Services/LookupServer/DNSAnswer.h
+++ b/Userland/Services/LookupServer/DNSAnswer.h
@@ -12,15 +12,19 @@
 
 namespace LookupServer {
 
+#define MDNS_CACHE_FLUSH 0x8000
+
 class DNSAnswer {
 public:
-    DNSAnswer(const DNSName& name, u16 type, u16 class_code, u32 ttl, const String& record_data);
+    DNSAnswer(const DNSName& name, u16 type, u16 class_code, u32 ttl, const String& record_data, bool mdns_cache_flush);
 
     const DNSName& name() const { return m_name; }
     u16 type() const { return m_type; }
     u16 class_code() const { return m_class_code; }
+    u16 raw_class_code() const { return m_class_code | (m_mdns_cache_flush ? MDNS_CACHE_FLUSH : 0); }
     u32 ttl() const { return m_ttl; }
     const String& record_data() const { return m_record_data; }
+    bool mdns_cache_flush() const { return m_mdns_cache_flush; }
 
     bool has_expired() const;
 
@@ -31,6 +35,7 @@ private:
     u32 m_ttl { 0 };
     time_t m_expiration_time { 0 };
     String m_record_data;
+    bool m_mdns_cache_flush { false };
 };
 
 }
diff --git a/Userland/Services/LookupServer/DNSPacket.cpp b/Userland/Services/LookupServer/DNSPacket.cpp
index e005a6ac9a..8cec959856 100644
--- a/Userland/Services/LookupServer/DNSPacket.cpp
+++ b/Userland/Services/LookupServer/DNSPacket.cpp
@@ -56,12 +56,12 @@ ByteBuffer DNSPacket::to_byte_buffer() const
     for (auto& question : m_questions) {
         stream << question.name();
         stream << htons(question.record_type());
-        stream << htons(question.class_code());
+        stream << htons(question.raw_class_code());
     }
     for (auto& answer : m_answers) {
         stream << answer.name();
         stream << htons(answer.type());
-        stream << htons(answer.class_code());
+        stream << htons(answer.raw_class_code());
         stream << htonl(answer.ttl());
         if (answer.type() == T_PTR) {
             DNSName name { answer.record_data() };
@@ -129,7 +129,9 @@ Optional<DNSPacket> DNSPacket::from_raw_packet(const u8* raw_data, size_t raw_si
             NetworkOrdered<u16> class_code;
         };
         auto& record_and_class = *(const RawDNSAnswerQuestion*)&raw_data[offset];
-        packet.m_questions.empend(name, record_and_class.record_type, record_and_class.class_code);
+        u16 class_code = record_and_class.class_code & ~MDNS_WANTS_UNICAST_RESPONSE;
+        bool mdns_wants_unicast_response = record_and_class.class_code & MDNS_WANTS_UNICAST_RESPONSE;
+        packet.m_questions.empend(name, record_and_class.record_type, class_code, mdns_wants_unicast_response);
         offset += 4;
         auto& question = packet.m_questions.last();
         dbgln_if(LOOKUPSERVER_DEBUG, "Question #{}: name=_{}_, type={}, class={}", i, question.name(), question.record_type(), question.class_code());
@@ -154,7 +156,9 @@ Optional<DNSPacket> DNSPacket::from_raw_packet(const u8* raw_data, size_t raw_si
             dbgln("data=(unimplemented record type {})", record.type());
         }
         dbgln_if(LOOKUPSERVER_DEBUG, "Answer   #{}: name=_{}_, type={}, ttl={}, length={}, data=_{}_", i, name, record.type(), record.ttl(), record.data_length(), data);
-        packet.m_answers.empend(name, record.type(), record.record_class(), record.ttl(), data);
+        u16 class_code = record.record_class() & ~MDNS_CACHE_FLUSH;
+        bool mdns_cache_flush = record.record_class() & MDNS_CACHE_FLUSH;
+        packet.m_answers.empend(name, record.type(), class_code, record.ttl(), data, mdns_cache_flush);
         offset += record.data_length();
     }
 
diff --git a/Userland/Services/LookupServer/DNSQuestion.h b/Userland/Services/LookupServer/DNSQuestion.h
index 870ceec9e0..dfe5826b55 100644
--- a/Userland/Services/LookupServer/DNSQuestion.h
+++ b/Userland/Services/LookupServer/DNSQuestion.h
@@ -11,23 +11,29 @@
 
 namespace LookupServer {
 
+#define MDNS_WANTS_UNICAST_RESPONSE 0x8000
+
 class DNSQuestion {
 public:
-    DNSQuestion(const DNSName& name, u16 record_type, u16 class_code)
+    DNSQuestion(const DNSName& name, u16 record_type, u16 class_code, bool mdns_wants_unicast_response)
         : m_name(name)
         , m_record_type(record_type)
         , m_class_code(class_code)
+        , m_mdns_wants_unicast_response(mdns_wants_unicast_response)
     {
     }
 
     u16 record_type() const { return m_record_type; }
     u16 class_code() const { return m_class_code; }
+    u16 raw_class_code() const { return (u16)m_class_code | (m_mdns_wants_unicast_response ? MDNS_WANTS_UNICAST_RESPONSE : 0); }
     const DNSName& name() const { return m_name; }
+    bool mdns_wants_unicast_response() const { return m_mdns_wants_unicast_response; }
 
 private:
     DNSName m_name;
     u16 m_record_type { 0 };
     u16 m_class_code { 0 };
+    bool m_mdns_wants_unicast_response { false };
 };
 
 }
diff --git a/Userland/Services/LookupServer/LookupServer.cpp b/Userland/Services/LookupServer/LookupServer.cpp
index 4e2da925d8..e20e775a36 100644
--- a/Userland/Services/LookupServer/LookupServer.cpp
+++ b/Userland/Services/LookupServer/LookupServer.cpp
@@ -75,7 +75,7 @@ void LookupServer::load_etc_hosts()
             m_etc_hosts.set(name, {});
             it = m_etc_hosts.find(name);
         }
-        it->value.empend(name, record_type, (u16)C_IN, static_ttl, data);
+        it->value.empend(name, record_type, (u16)C_IN, static_ttl, data, false);
     };
 
     auto file = Core::File::construct("/etc/hosts");
@@ -123,7 +123,8 @@ Vector<DNSAnswer> LookupServer::lookup(const DNSName& name, unsigned short recor
             answer.type(),
             answer.class_code(),
             answer.ttl(),
-            answer.record_data()
+            answer.record_data(),
+            answer.mdns_cache_flush(),
         };
         answers.append(answer_with_original_case);
     };
@@ -197,7 +198,7 @@ Vector<DNSAnswer> LookupServer::lookup(const DNSName& name, const String& namese
     DNSName name_in_question = name;
     if (should_randomize_case == ShouldRandomizeCase::Yes)
         name_in_question.randomize_case();
-    request.add_question({ name_in_question, record_type, C_IN });
+    request.add_question({ name_in_question, record_type, C_IN, false });
 
     auto buffer = request.to_byte_buffer();
 
diff --git a/Userland/Services/LookupServer/MulticastDNS.cpp b/Userland/Services/LookupServer/MulticastDNS.cpp
index 768679af1a..4e903c74ed 100644
--- a/Userland/Services/LookupServer/MulticastDNS.cpp
+++ b/Userland/Services/LookupServer/MulticastDNS.cpp
@@ -88,9 +88,10 @@ void MulticastDNS::announce()
         DNSAnswer answer {
             m_hostname,
             T_A,
-            C_IN | 0x8000,
+            C_IN,
             120,
-            String { (const char*)&raw_addr, sizeof(raw_addr) }
+            String { (const char*)&raw_addr, sizeof(raw_addr) },
+            true,
         };
         response.add_answer(answer);
     }
@@ -141,7 +142,7 @@ Vector<DNSAnswer> MulticastDNS::lookup(const DNSName& name, unsigned short recor
 {
     DNSPacket request;
     request.set_is_query();
-    request.add_question({ name, record_type, C_IN });
+    request.add_question({ name, record_type, C_IN, false });
 
     if (emit_packet(request) < 0) {
         perror("failed to emit request packet");