Address review comments on Darwin certificate conversion function. (#…

…22431) Fixes #22206
project-chip · Sep 6, 2022 · df11d01 · df11d01
1 parent 001e7bf
commit df11d01
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Showing 2 changed files with 14 additions and 7 deletions.
diff --git a/src/darwin/Framework/CHIP/MTRCertificates.h b/src/darwin/Framework/CHIP/MTRCertificates.h
@@ -125,8 +125,15 @@ NS_ASSUME_NONNULL_BEGIN
 + (nullable NSData *)generateCertificateSigningRequest:(id<MTRKeypair>)keypair
                                                  error:(NSError * __autoreleasing _Nullable * _Nullable)error;
 
-/** Converts the given X.509v3 certificate to the CHIP certificate format. */
-+ (nullable NSData *)convertToCHIPCertFromX509Cert:(NSData *)x509Certificate;
+/**
+ * Convert the given X.509v3 DER encoded certificate to the Matter certificate
+ * format.
+ *
+ * Returns nil if the conversion fails (e.g. if the input data cannot be parsed
+ * as a DER encoded X.509 certificate, or if the certificate cannot be
+ * represented in the Matter certificate format).
+ */
++ (nullable NSData *)convertX509Certificate:(NSData *)x509Certificate;
 
 @end
 

diff --git a/src/darwin/Framework/CHIP/MTRCertificates.mm b/src/darwin/Framework/CHIP/MTRCertificates.mm
@@ -197,21 +197,21 @@ + (nullable NSData *)generateCertificateSigningRequest:(id<MTRKeypair>)keypair
     return nil;
 }
 
-+ (nullable NSData *)convertToCHIPCertFromX509Cert:(NSData *)x509Certificate
++ (nullable NSData *)convertX509Certificate:(NSData *)x509Certificate
 {
 
-    chip::ByteSpan x509CertBytes = chip::ByteSpan((uint8_t *) x509Certificate.bytes, x509Certificate.length);
+    chip::ByteSpan x509CertBytes = AsByteSpan(x509Certificate);
 
-    NSMutableData * chipCertBuffer = [[NSMutableData alloc] initWithLength:chip::Credentials::kMaxCHIPCertLength];
-    chip::MutableByteSpan chipCertBytes((uint8_t *) chipCertBuffer.mutableBytes, chip::Credentials::kMaxCHIPCertLength);
+    uint8_t chipCertBuffer[chip::Credentials::kMaxCHIPCertLength];
+    chip::MutableByteSpan chipCertBytes(chipCertBuffer);
 
     CHIP_ERROR errorCode = chip::Credentials::ConvertX509CertToChipCert(x509CertBytes, chipCertBytes);
     MTR_LOG_ERROR("ConvertX509CertToChipCert: %{public}s", chip::ErrorStr(errorCode));
 
     if (errorCode != CHIP_NO_ERROR)
         return nil;
 
-    return [NSData dataWithBytes:chipCertBytes.data() length:chipCertBytes.size()];
+    return AsData(chipCertBytes);
 }
 
 @end