From 80d134ed829af3c922e8973fa86a80fe3f10b9f1 Mon Sep 17 00:00:00 2001
From: Mikhail Burshteyn <michael.burshteyn@gmail.com>
Date: Thu, 25 Aug 2022 11:52:05 -0600
Subject: [PATCH] Expose `Credentials::ConvertX509CertToChipCert` to Obj-C.
 (#22113)

* Expose `Credentials::ConvertX509CertToChipCert` to Obj-C.

* Restyled by clang-format

Co-authored-by: Restyled.io <commits@restyled.io>
---
 src/darwin/Framework/CHIP/MTRCertificates.h  |  3 +++
 src/darwin/Framework/CHIP/MTRCertificates.mm | 18 ++++++++++++++++++
 2 files changed, 21 insertions(+)

diff --git a/src/darwin/Framework/CHIP/MTRCertificates.h b/src/darwin/Framework/CHIP/MTRCertificates.h
index 301ab76f5b5ad3..f46999c661b5bc 100644
--- a/src/darwin/Framework/CHIP/MTRCertificates.h
+++ b/src/darwin/Framework/CHIP/MTRCertificates.h
@@ -125,6 +125,9 @@ 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;
+
 @end
 
 NS_ASSUME_NONNULL_END
diff --git a/src/darwin/Framework/CHIP/MTRCertificates.mm b/src/darwin/Framework/CHIP/MTRCertificates.mm
index 80f3d9e10333bb..4caf69bf040ab8 100644
--- a/src/darwin/Framework/CHIP/MTRCertificates.mm
+++ b/src/darwin/Framework/CHIP/MTRCertificates.mm
@@ -16,6 +16,7 @@
 
 #import "MTRCertificates.h"
 #import "MTRError_Internal.h"
+#import "MTRLogging.h"
 #import "MTRMemory.h"
 #import "MTROperationalCredentialsDelegate.h"
 #import "MTRP256KeypairBridge.h"
@@ -196,4 +197,21 @@ + (nullable NSData *)generateCertificateSigningRequest:(id<MTRKeypair>)keypair
     return nil;
 }
 
++ (nullable NSData *)convertToCHIPCertFromX509Cert:(NSData *)x509Certificate
+{
+
+    chip::ByteSpan x509CertBytes = chip::ByteSpan((uint8_t *) x509Certificate.bytes, x509Certificate.length);
+
+    NSMutableData * chipCertBuffer = [[NSMutableData alloc] initWithLength:chip::Credentials::kMaxCHIPCertLength];
+    chip::MutableByteSpan chipCertBytes((uint8_t *) chipCertBuffer.mutableBytes, chip::Credentials::kMaxCHIPCertLength);
+
+    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()];
+}
+
 @end