Darwin: mark copyPublicKey as CF_RETURNS_RETAINED (project-chip#37022)

for correct memory management when called from Swift.  added a test that shows how the annotation affects typical callees.

Co-authored-by: Andrei Litvin <andy314@gmail.com>

Author: kiel-apple

src/darwin/Framework/CHIP/MTRKeypair.h

@@ -38,7 +38,7 @@ MTR_AVAILABLE(ios(16.1), macos(13.0), watchos(9.1), tvos(16.1))
 /**
  * @brief Returns a copy of the public key for the keypair.
  */
-- (SecKeyRef)copyPublicKey MTR_AVAILABLE(ios(18.4), macos(15.4), watchos(11.4), tvos(18.4));
+- (SecKeyRef)copyPublicKey CF_RETURNS_RETAINED MTR_AVAILABLE(ios(18.4), macos(15.4), watchos(11.4), tvos(18.4));
 
 /**
  * @brief Returns public key for the keypair without adding a reference. DEPRECATED - please use copyPublicKey, otherwise this will leak.

src/darwin/Framework/CHIPTests/MTRSwiftCertificateTests.swift

@@ -0,0 +1,54 @@
+/**
+ *    Copyright (c) 2024 Project CHIP Authors
+ *
+ *    Licensed under the Apache License, Version 2.0 (the "License");
+ *    you may not use this file except in compliance with the License.
+ *    You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ *    Unless required by applicable law or agreed to in writing, software
+ *    distributed under the License is distributed on an "AS IS" BASIS,
+ *    WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ *    See the License for the specific language governing permissions and
+ *    limitations under the License.
+ */
+
+import Foundation
+
+class MTRSwiftCertificateTests : XCTestCase {
+    func testGenerateIntermediateCert() {
+        let rootKeys = MTRTestKeys()
+        do {
+            let rootCert = try MTRCertificates.createRootCertificate(rootKeys, issuerID: nil, fabricID: nil)
+            XCTAssertNotNil(rootCert)
+
+            let intermediateKeys = MTRTestKeys()
+            XCTAssertNotNil(intermediateKeys)
+
+            // NB: `copyPublicKey` returns Unmanaged<SecKey> if `copyPublicKey` lacks CF_RETURNS_RETAINED annotation.
+            let intermediatePublicKey = intermediateKeys.copyPublicKey()
+            XCTAssertNotNil(intermediatePublicKey)
+
+            let intermediateCert = try MTRCertificates.createIntermediateCertificate(rootKeys, rootCertificate: rootCert, intermediatePublicKey: intermediatePublicKey, issuerID: nil as NSNumber?, fabricID: nil)
+            XCTAssertNotNil(intermediateCert)
+
+            guard let tlvCert = MTRCertificates.convertX509Certificate(intermediateCert) else {
+                XCTFail()
+                return
+            }
+            XCTAssertNotNil(tlvCert)
+
+            guard let derCert = MTRCertificates.convertMatterCertificate(tlvCert) else {
+                XCTFail()
+                return
+            }
+            XCTAssertNotNil(derCert)
+
+            XCTAssertEqual(intermediateCert, derCert)
+
+        } catch {
+            XCTFail()
+        }
+    }
+}

src/darwin/Framework/Matter.xcodeproj/project.pbxproj

@@ -348,6 +348,7 @@
 		9B5CCB5D2C6EC890009DD99B /* MTRDevice_XPC.h in Headers */ = {isa = PBXBuildFile; fileRef = 9B5CCB5A2C6EC890009DD99B /* MTRDevice_XPC.h */; };
 		9B5CCB602C6EE29E009DD99B /* MTRDeviceControllerXPCParameters.mm in Sources */ = {isa = PBXBuildFile; fileRef = 9B5CCB5F2C6EE29E009DD99B /* MTRDeviceControllerXPCParameters.mm */; };
 		9B5CCB612C6EE29E009DD99B /* MTRDeviceControllerXPCParameters.h in Headers */ = {isa = PBXBuildFile; fileRef = 9B5CCB5E2C6EE29E009DD99B /* MTRDeviceControllerXPCParameters.h */; };
+		9BC9E5872D3099FF00784A21 /* MTRSwiftCertificateTests.swift in Sources */ = {isa = PBXBuildFile; fileRef = 9BC9E5862D3099FF00784A21 /* MTRSwiftCertificateTests.swift */; };
 		9BDA2A062C5D9AF800A32BDD /* MTRDevice_Concrete.mm in Sources */ = {isa = PBXBuildFile; fileRef = 9BDA2A052C5D9AF800A32BDD /* MTRDevice_Concrete.mm */; };
 		9BDA2A082C5D9AFB00A32BDD /* MTRDevice_Concrete.h in Headers */ = {isa = PBXBuildFile; fileRef = 9BDA2A072C5D9AFB00A32BDD /* MTRDevice_Concrete.h */; };
 		9BFE5D502C6D3075007D4319 /* MTRDeviceController_XPC.h in Headers */ = {isa = PBXBuildFile; fileRef = 9BFE5D4E2C6D3075007D4319 /* MTRDeviceController_XPC.h */; };
@@ -835,6 +836,7 @@
 		9B5CCB5B2C6EC890009DD99B /* MTRDevice_XPC.mm */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.objcpp; path = MTRDevice_XPC.mm; sourceTree = "<group>"; };
 		9B5CCB5E2C6EE29E009DD99B /* MTRDeviceControllerXPCParameters.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = MTRDeviceControllerXPCParameters.h; sourceTree = "<group>"; };
 		9B5CCB5F2C6EE29E009DD99B /* MTRDeviceControllerXPCParameters.mm */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.objcpp; path = MTRDeviceControllerXPCParameters.mm; sourceTree = "<group>"; };
+		9BC9E5862D3099FF00784A21 /* MTRSwiftCertificateTests.swift */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.swift; path = MTRSwiftCertificateTests.swift; sourceTree = "<group>"; };
 		9BDA2A052C5D9AF800A32BDD /* MTRDevice_Concrete.mm */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.cpp.objcpp; path = MTRDevice_Concrete.mm; sourceTree = "<group>"; };
 		9BDA2A072C5D9AFB00A32BDD /* MTRDevice_Concrete.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = MTRDevice_Concrete.h; sourceTree = "<group>"; };
 		9BFE5D4E2C6D3075007D4319 /* MTRDeviceController_XPC.h */ = {isa = PBXFileReference; lastKnownFileType = sourcecode.c.h; path = MTRDeviceController_XPC.h; sourceTree = "<group>"; };
@@ -1634,6 +1636,7 @@
 				3D4733AE2BDF1B80003DC19B /* MTRSetupPayloadTests.m */,
 				519498312A25581C00B3BABE /* MTRSetupPayloadInitializationTests.m */,
 				51E0FC0F2ACBBF230001E197 /* MTRSwiftDeviceTests.swift */,
+				9BC9E5862D3099FF00784A21 /* MTRSwiftCertificateTests.swift */,
 				5143851D2A65885500EDC8E6 /* MTRSwiftPairingTests.swift */,
 				997DED1926955D0200975E97 /* MTRThreadOperationalDatasetTests.mm */,
 				5A7947DD27BEC3F500434CF2 /* MTRXPCListenerSampleTests.m */,
@@ -2344,6 +2347,7 @@
 			isa = PBXSourcesBuildPhase;
 			buildActionMask = 2147483647;
 			files = (
+				9BC9E5872D3099FF00784A21 /* MTRSwiftCertificateTests.swift in Sources */,
 				51742B4E29CB6B88009974FE /* MTRPairingTests.m in Sources */,
 				5131BF662BE2E1B000D5D6BC /* MTRTestCase.mm in Sources */,
 				51669AF02913204400F4AA36 /* MTRBackwardsCompatTests.m in Sources */,