Add Support for CS_INVALIDATED Events

Source/common/santa.proto

@@ -381,6 +381,11 @@ message Unlink {
   optional FileInfo target = 2;
 }
 
+// Information about a processes codesigning invalidation event
+message CodesigningInvalidated {
+  optional ProcessInfoLight instigator = 1;
+}
+
 // Information about a link event
 message Link {
   // The process performing the link
@@ -529,6 +534,7 @@ message SantaMessage {
     Bundle bundle = 19;
     Allowlist allowlist = 20;
     FileAccess file_access = 21;
+    CodesigningInvalidated codesigning_invalidated = 22;
   };
 }
 

Source/santad/EventProviders/EndpointSecurity/EnrichedTypes.h

@@ -320,9 +320,19 @@ class EnrichedUnlink : public EnrichedEventType {
   EnrichedFile target_;
 };
 
+class EnrichedCSInvalidated : public EnrichedEventType {
+ public:
+  EnrichedCSInvalidated(Message &&es_msg, EnrichedProcess &&instigator)
+      : EnrichedEventType(std::move(es_msg), std::move(instigator)) {}
+  EnrichedCSInvalidated(EnrichedCSInvalidated &&other)
+      : EnrichedEventType(std::move(other)) {}
+  EnrichedCSInvalidated(const EnrichedCSInvalidated &other) = delete;
+};
+
 using EnrichedType =
     std::variant<EnrichedClose, EnrichedExchange, EnrichedExec, EnrichedExit,
-                 EnrichedFork, EnrichedLink, EnrichedRename, EnrichedUnlink>;
+                 EnrichedFork, EnrichedLink, EnrichedRename, EnrichedUnlink,
+                 EnrichedCSInvalidated>;
 
 class EnrichedMessage {
  public:

Source/santad/EventProviders/EndpointSecurity/Enricher.mm

@@ -74,6 +74,9 @@
     case ES_EVENT_TYPE_NOTIFY_UNLINK:
       return std::make_unique<EnrichedMessage>(EnrichedUnlink(
         std::move(es_msg), Enrich(*es_msg->process), Enrich(*es_msg->event.unlink.target)));
+    case ES_EVENT_TYPE_NOTIFY_CS_INVALIDATED:
+      return std::make_unique<EnrichedMessage>(
+        EnrichedCSInvalidated(std::move(es_msg), Enrich(*es_msg->process)));
     default:
       // This is a programming error
       LOGE(@"Attempting to enrich an unhandled event type: %d", es_msg->event_type);

Source/santad/Logs/EndpointSecurity/Serializers/BasicString.h

@@ -55,6 +55,8 @@ class BasicString : public Serializer {
     const santa::santad::event_providers::endpoint_security::EnrichedRename &) override;
   std::vector<uint8_t> SerializeMessage(
     const santa::santad::event_providers::endpoint_security::EnrichedUnlink &) override;
+  std::vector<uint8_t> SerializeMessage(
+    const santa::santad::event_providers::endpoint_security::EnrichedCSInvalidated &) override;
 
   std::vector<uint8_t> SerializeFileAccess(
     const std::string &policy_version, const std::string &policy_name,

Source/santad/Logs/EndpointSecurity/Serializers/BasicString.mm

@@ -45,6 +45,7 @@
 using santa::santad::event_providers::endpoint_security::EnrichedProcess;
 using santa::santad::event_providers::endpoint_security::EnrichedRename;
 using santa::santad::event_providers::endpoint_security::EnrichedUnlink;
+using santa::santad::event_providers::endpoint_security::EnrichedCSInvalidated;
 using santa::santad::event_providers::endpoint_security::Message;
 using santa::santad::logs::endpoint_security::serializers::Utilities::MountFromName;
 using santa::santad::logs::endpoint_security::serializers::Utilities::NonNull;
@@ -412,6 +413,19 @@ static inline void AppendUserGroup(std::string &str, const audit_token_t &tok,
   return FinalizeString(str);
 }
 
+std::vector<uint8_t> BasicString::SerializeMessage(const EnrichedCSInvalidated &msg) {
+  const es_message_t &esm = msg.es_msg();
+  std::string str = CreateDefaultString();
+
+  str.append("action=CODESIGNING_INVALIDATED");
+  AppendProcess(str, esm.process);
+  AppendUserGroup(str, esm.process->audit_token, msg.instigator().real_user(),
+                  msg.instigator().real_group());
+  str.append("|codesigning_flags=");
+  str.append([NSString stringWithFormat:@"0x%08x", esm.process->codesigning_flags].UTF8String);
+  return FinalizeString(str);
+}
+
 std::vector<uint8_t> BasicString::SerializeFileAccess(const std::string &policy_version,
                                                       const std::string &policy_name,
                                                       const Message &msg,

Source/santad/Logs/EndpointSecurity/Serializers/BasicStringTest.mm

@@ -251,6 +251,20 @@ - (void)testSerializeMessageUnlink {
   XCTAssertCppStringEqual(got, want);
 }
 
+- (void)testSerializeMessageCSInvalidated {
+  es_file_t procFile = MakeESFile("foo");
+  es_process_t proc = MakeESProcess(&procFile, MakeAuditToken(12, 34), MakeAuditToken(56, 78));
+  es_message_t esMsg = MakeESMessage(ES_EVENT_TYPE_NOTIFY_CS_INVALIDATED, &proc);
+
+  std::string got = BasicStringSerializeMessage(&esMsg);
+  std::string want =
+    "action=CODESIGNING_INVALIDATED"
+    "|pid=12|ppid=56|process=foo|processpath=foo"
+    "|uid=-2|user=nobody|gid=-1|group=nogroup|codesigning_flags=0x00000000|machineid=my_id\n";
+
+  XCTAssertCppStringEqual(got, want);
+}
+
 - (void)testGetAccessTypeString {
   std::map<es_event_type_t, std::string> accessTypeToString = {
     {ES_EVENT_TYPE_AUTH_OPEN, "OPEN"},         {ES_EVENT_TYPE_AUTH_LINK, "LINK"},

Source/santad/Logs/EndpointSecurity/Serializers/Empty.h

@@ -47,6 +47,8 @@ class Empty : public Serializer {
     const santa::santad::event_providers::endpoint_security::EnrichedRename &) override;
   std::vector<uint8_t> SerializeMessage(
     const santa::santad::event_providers::endpoint_security::EnrichedUnlink &) override;
+  std::vector<uint8_t> SerializeMessage(
+    const santa::santad::event_providers::endpoint_security::EnrichedCSInvalidated &) override;
 
   std::vector<uint8_t> SerializeFileAccess(
     const std::string &policy_version, const std::string &policy_name,

Source/santad/Logs/EndpointSecurity/Serializers/Empty.mm

@@ -15,6 +15,7 @@
 #include "Source/santad/Logs/EndpointSecurity/Serializers/Empty.h"
 
 using santa::santad::event_providers::endpoint_security::EnrichedClose;
+using santa::santad::event_providers::endpoint_security::EnrichedCSInvalidated;
 using santa::santad::event_providers::endpoint_security::EnrichedExchange;
 using santa::santad::event_providers::endpoint_security::EnrichedExec;
 using santa::santad::event_providers::endpoint_security::EnrichedExit;
@@ -65,6 +66,10 @@
   return {};
 }
 
+std::vector<uint8_t> Empty::SerializeMessage(const EnrichedCSInvalidated &msg) {
+  return {};
+}
+
 std::vector<uint8_t> Empty::SerializeFileAccess(const std::string &policy_version,
                                                 const std::string &policy_name, const Message &msg,
                                                 const EnrichedProcess &enriched_process,

Source/santad/Logs/EndpointSecurity/Serializers/EmptyTest.mm

@@ -43,6 +43,7 @@ - (void)testAllSerializersReturnEmptyVector {
   XCTAssertEqual(e->SerializeMessage(*(es::EnrichedLink *)&fake).size(), 0);
   XCTAssertEqual(e->SerializeMessage(*(es::EnrichedRename *)&fake).size(), 0);
   XCTAssertEqual(e->SerializeMessage(*(es::EnrichedUnlink *)&fake).size(), 0);
+  XCTAssertEqual(e->SerializeMessage(*(es::EnrichedCSInvalidated *)&fake).size(), 0);
 
   XCTAssertEqual(e->SerializeAllowlist(*(es::Message *)&fake, "").size(), 0);
   XCTAssertEqual(e->SerializeBundleHashingEvent(nil).size(), 0);

Source/santad/Logs/EndpointSecurity/Serializers/Protobuf.h

@@ -56,6 +56,8 @@ class Protobuf : public Serializer {
     const santa::santad::event_providers::endpoint_security::EnrichedRename &) override;
   std::vector<uint8_t> SerializeMessage(
     const santa::santad::event_providers::endpoint_security::EnrichedUnlink &) override;
+  std::vector<uint8_t> SerializeMessage(
+    const santa::santad::event_providers::endpoint_security::EnrichedCSInvalidated &) override;
 
   std::vector<uint8_t> SerializeFileAccess(
     const std::string &policy_version, const std::string &policy_name,

Source/santad/Logs/EndpointSecurity/Serializers/Protobuf.mm

@@ -46,6 +46,7 @@
 using santa::common::NSStringToUTF8StringView;
 using santa::santad::event_providers::endpoint_security::EndpointSecurityAPI;
 using santa::santad::event_providers::endpoint_security::EnrichedClose;
+using santa::santad::event_providers::endpoint_security::EnrichedCSInvalidated;
 using santa::santad::event_providers::endpoint_security::EnrichedEventType;
 using santa::santad::event_providers::endpoint_security::EnrichedExchange;
 using santa::santad::event_providers::endpoint_security::EnrichedExec;
@@ -600,6 +601,17 @@ static inline void EncodeCertificateInfo(::pbv1::CertificateInfo *pb_cert_info,
   return FinalizeProto(santa_msg);
 }
 
+std::vector<uint8_t> Protobuf::SerializeMessage(const EnrichedCSInvalidated &msg) {
+  Arena arena;
+  ::pbv1::SantaMessage *santa_msg = CreateDefaultProto(&arena, msg);
+
+  ::pbv1::CodesigningInvalidated *pb_cs_invalidated = santa_msg->mutable_codesigning_invalidated();
+  EncodeProcessInfoLight(pb_cs_invalidated->mutable_instigator(), msg.es_msg().version,
+                         msg.es_msg().process, msg.instigator());
+
+  return FinalizeProto(santa_msg);
+}
+
 std::vector<uint8_t> Protobuf::SerializeFileAccess(const std::string &policy_version,
                                                    const std::string &policy_name,
                                                    const Message &msg,

Source/santad/Logs/EndpointSecurity/Serializers/ProtobufTest.mm

@@ -110,6 +110,7 @@ JsonPrintOptions DefaultJsonPrintOptions() {
     case ES_EVENT_TYPE_NOTIFY_LINK: return @"link.json";
     case ES_EVENT_TYPE_NOTIFY_RENAME: return @"rename.json";
     case ES_EVENT_TYPE_NOTIFY_UNLINK: return @"unlink.json";
+    case ES_EVENT_TYPE_NOTIFY_CS_INVALIDATED: return @"cs_invalidated.json";
     default: XCTFail(@"Unhandled event type: %d", eventType); return nil;
   }
 }
@@ -145,6 +146,7 @@ bool CompareTime(const Timestamp &timestamp, struct timespec ts) {
     case ::pbv1::SantaMessage::kBundle: return santaMsg.bundle();
     case ::pbv1::SantaMessage::kAllowlist: return santaMsg.allowlist();
     case ::pbv1::SantaMessage::kFileAccess: return santaMsg.file_access();
+    case ::pbv1::SantaMessage::kCodesigningInvalidated: return santaMsg.codesigning_invalidated();
     case ::pbv1::SantaMessage::EVENT_NOT_SET:
       XCTFail(@"Protobuf message SantaMessage did not set an 'event' field");
       OS_FALLTHROUGH;
@@ -668,6 +670,14 @@ - (void)testSerializeMessageUnlink {
                           json:NO];
 }
 
+- (void)testSerializeMessageCodesigningInvalidated {
+  [self serializeAndCheckEvent:ES_EVENT_TYPE_NOTIFY_CS_INVALIDATED
+                  messageSetup:^(std::shared_ptr<MockEndpointSecurityAPI> mockESApi,
+                                 es_message_t *esMsg) {
+                  }
+                          json:NO];
+}
+
 - (void)testGetAccessType {
   std::map<es_event_type_t, ::pbv1::FileAccess::AccessType> eventTypeToAccessType = {
     {ES_EVENT_TYPE_AUTH_CLONE, ::pbv1::FileAccess::ACCESS_TYPE_CLONE},

Source/santad/Logs/EndpointSecurity/Serializers/Serializer.h

@@ -61,6 +61,8 @@ class Serializer {
     const santa::santad::event_providers::endpoint_security::EnrichedRename &) = 0;
   virtual std::vector<uint8_t> SerializeMessage(
     const santa::santad::event_providers::endpoint_security::EnrichedUnlink &) = 0;
+  virtual std::vector<uint8_t> SerializeMessage(
+    const santa::santad::event_providers::endpoint_security::EnrichedCSInvalidated &) = 0;
 
   virtual std::vector<uint8_t> SerializeFileAccess(
     const std::string &policy_version, const std::string &policy_name,
@@ -95,6 +97,8 @@ class Serializer {
     const santa::santad::event_providers::endpoint_security::EnrichedRename &);
   std::vector<uint8_t> SerializeMessageTemplate(
     const santa::santad::event_providers::endpoint_security::EnrichedUnlink &);
+  std::vector<uint8_t> SerializeMessageTemplate(
+    const santa::santad::event_providers::endpoint_security::EnrichedCSInvalidated &);
 
   bool enabled_machine_id_ = false;
   std::string machine_id_;

Source/santad/Logs/EndpointSecurity/Serializers/Serializer.mm

@@ -74,5 +74,8 @@
 std::vector<uint8_t> Serializer::SerializeMessageTemplate(const es::EnrichedUnlink &msg) {
   return SerializeMessage(msg);
 }
+std::vector<uint8_t> Serializer::SerializeMessageTemplate(const es::EnrichedCSInvalidated &msg) {
+  return SerializeMessage(msg);
+}
 
 };  // namespace santa::santad::logs::endpoint_security::serializers

Source/santad/testdata/protobuf/v1/cs_invalidated.json

@@ -0,0 +1,35 @@
+{
+ "instigator": {
+  "id": {
+   "pid": 12,
+   "pidversion": 34
+  },
+  "parent_id": {
+   "pid": 56,
+   "pidversion": 78
+  },
+  "original_parent_pid": 56,
+  "group_id": 111,
+  "session_id": 222,
+  "effective_user": {
+   "uid": -2,
+   "name": "nobody"
+  },
+  "effective_group": {
+   "gid": -1,
+   "name": "nogroup"
+  },
+  "real_user": {
+   "uid": -2,
+   "name": "nobody"
+  },
+  "real_group": {
+   "gid": -1,
+   "name": "nogroup"
+  },
+  "executable": {
+   "path": "foo",
+   "truncated": false
+  }
+ }
+}

Source/santad/testdata/protobuf/v2/cs_invalidated.json

@@ -0,0 +1,35 @@
+{
+ "instigator": {
+  "id": {
+   "pid": 12,
+   "pidversion": 34
+  },
+  "parent_id": {
+   "pid": 56,
+   "pidversion": 78
+  },
+  "original_parent_pid": 56,
+  "group_id": 111,
+  "session_id": 222,
+  "effective_user": {
+   "uid": -2,
+   "name": "nobody"
+  },
+  "effective_group": {
+   "gid": -1,
+   "name": "nogroup"
+  },
+  "real_user": {
+   "uid": -2,
+   "name": "nobody"
+  },
+  "real_group": {
+   "gid": -1,
+   "name": "nogroup"
+  },
+  "executable": {
+   "path": "foo",
+   "truncated": false
+  }
+ }
+}

Source/santad/testdata/protobuf/v4/cs_invalidated.json

@@ -0,0 +1,35 @@
+{
+ "instigator": {
+  "id": {
+   "pid": 12,
+   "pidversion": 34
+  },
+  "parent_id": {
+   "pid": 56,
+   "pidversion": 78
+  },
+  "original_parent_pid": 56,
+  "group_id": 111,
+  "session_id": 222,
+  "effective_user": {
+   "uid": -2,
+   "name": "nobody"
+  },
+  "effective_group": {
+   "gid": -1,
+   "name": "nogroup"
+  },
+  "real_user": {
+   "uid": -2,
+   "name": "nobody"
+  },
+  "real_group": {
+   "gid": -1,
+   "name": "nogroup"
+  },
+  "executable": {
+   "path": "foo",
+   "truncated": false
+  }
+ }
+}

Source/santad/testdata/protobuf/v5/cs_invalidated.json

@@ -0,0 +1,35 @@
+{
+ "instigator": {
+  "id": {
+   "pid": 12,
+   "pidversion": 34
+  },
+  "parent_id": {
+   "pid": 56,
+   "pidversion": 78
+  },
+  "original_parent_pid": 56,
+  "group_id": 111,
+  "session_id": 222,
+  "effective_user": {
+   "uid": -2,
+   "name": "nobody"
+  },
+  "effective_group": {
+   "gid": -1,
+   "name": "nogroup"
+  },
+  "real_user": {
+   "uid": -2,
+   "name": "nobody"
+  },
+  "real_group": {
+   "gid": -1,
+   "name": "nogroup"
+  },
+  "executable": {
+   "path": "foo",
+   "truncated": false
+  }
+ }
+}