Allow multiple private key references in Unix PFXes

src/libraries/System.Security.Cryptography.X509Certificates/src/Internal/Cryptography/Pal.Android/AndroidCertificatePal.cs

@@ -52,6 +52,7 @@ public static ICertificatePal FromBlob(ReadOnlySpan<byte> rawData, SafePasswordH
         {
             Debug.Assert(password != null);
 
+            bool ephemeralSpecified = keyStorageFlags.HasFlag(X509KeyStorageFlags.EphemeralKeySet);
             X509ContentType contentType = X509Certificate2.GetCertContentType(rawData);
 
             switch (contentType)
@@ -62,7 +63,7 @@ public static ICertificatePal FromBlob(ReadOnlySpan<byte> rawData, SafePasswordH
                     // We don't support determining this on Android right now, so we throw.
                     throw new CryptographicException(SR.Cryptography_X509_PKCS7_NoSigner);
                 case X509ContentType.Pkcs12:
-                    return ReadPkcs12(rawData, password);
+                    return ReadPkcs12(rawData, password, ephemeralSpecified);
                 case X509ContentType.Cert:
                 default:
                 {
@@ -104,11 +105,11 @@ internal static bool TryReadX509(ReadOnlySpan<byte> rawData, [NotNullWhen(true)]
             return true;
         }
 
-        private static ICertificatePal ReadPkcs12(ReadOnlySpan<byte> rawData, SafePasswordHandle password)
+        private static ICertificatePal ReadPkcs12(ReadOnlySpan<byte> rawData, SafePasswordHandle password, bool ephemeralSpecified)
         {
             using (var reader = new AndroidPkcs12Reader(rawData))
             {
-                reader.Decrypt(password);
+                reader.Decrypt(password, ephemeralSpecified);
 
                 UnixPkcs12Reader.CertAndKey certAndKey = reader.GetSingleCert();
                 AndroidCertificatePal pal = (AndroidCertificatePal)certAndKey.Cert!;

src/libraries/System.Security.Cryptography.X509Certificates/src/Internal/Cryptography/Pal.Android/StorePal.cs

@@ -23,9 +23,11 @@ public static ILoaderPal FromBlob(ReadOnlySpan<byte> rawData, SafePasswordHandle
             Debug.Assert(password != null);
 
             X509ContentType contentType = X509Certificate2.GetCertContentType(rawData);
+            bool ephemeralSpecified = keyStorageFlags.HasFlag(X509KeyStorageFlags.EphemeralKeySet);
+
             if (contentType == X509ContentType.Pkcs12)
             {
-                ICertificatePal[] certPals = ReadPkcs12Collection(rawData, password);
+                ICertificatePal[] certPals = ReadPkcs12Collection(rawData, password, ephemeralSpecified);
                 return new AndroidCertLoader(certPals);
             }
             else
@@ -108,11 +110,14 @@ public static IStorePal FromSystemStore(string storeName, StoreLocation storeLoc
             throw new CryptographicException(message, new PlatformNotSupportedException(message));
         }
 
-        private static ICertificatePal[] ReadPkcs12Collection(ReadOnlySpan<byte> rawData, SafePasswordHandle password)
+        private static ICertificatePal[] ReadPkcs12Collection(
+            ReadOnlySpan<byte> rawData,
+            SafePasswordHandle password,
+            bool ephemeralSpecified)
         {
             using (var reader = new AndroidPkcs12Reader(rawData))
             {
-                reader.Decrypt(password);
+                reader.Decrypt(password, ephemeralSpecified);
 
                 ICertificatePal[] certs = new ICertificatePal[reader.GetCertCount()];
                 int idx = 0;

src/libraries/System.Security.Cryptography.X509Certificates/src/Internal/Cryptography/Pal.OSX/AppleCertificatePal.Pkcs12.cs

@@ -19,7 +19,7 @@ internal sealed partial class AppleCertificatePal : ICertificatePal
         {
             using (ApplePkcs12Reader reader = new ApplePkcs12Reader(rawData))
             {
-                reader.Decrypt(password);
+                reader.Decrypt(password, ephemeralSpecified: false);
 
                 UnixPkcs12Reader.CertAndKey certAndKey = reader.GetSingleCert();
                 AppleCertificatePal pal = (AppleCertificatePal)certAndKey.Cert!;

src/libraries/System.Security.Cryptography.X509Certificates/src/Internal/Cryptography/Pal.OSX/StorePal.cs

@@ -47,7 +47,7 @@ public static ILoaderPal FromBlob(ReadOnlySpan<byte> rawData, SafePasswordHandle
                     ? Interop.AppleCrypto.SecKeychainCopyDefault()
                     : Interop.AppleCrypto.CreateTemporaryKeychain();
 
-                return ImportPkcs12(rawData, password, exportable, keychain);
+                return ImportPkcs12(rawData, password, exportable, ephemeralSpecified: false, keychain);
             }
 
             SafeCFArrayHandle certs = Interop.AppleCrypto.X509ImportCollection(
@@ -64,13 +64,14 @@ public static ILoaderPal FromBlob(ReadOnlySpan<byte> rawData, SafePasswordHandle
             ReadOnlySpan<byte> rawData,
             SafePasswordHandle password,
             bool exportable,
+            bool ephemeralSpecified,
             SafeKeychainHandle keychain)
         {
             ApplePkcs12Reader reader = new ApplePkcs12Reader(rawData);
 
             try
             {
-                reader.Decrypt(password);
+                reader.Decrypt(password, ephemeralSpecified);
                 return new ApplePkcs12CertLoader(reader, keychain, password, exportable);
             }
             catch

src/libraries/System.Security.Cryptography.X509Certificates/src/Internal/Cryptography/Pal.Unix/OpenSslX509CertificateReader.cs

@@ -49,12 +49,13 @@ public static ICertificatePal FromBlob(ReadOnlySpan<byte> rawData, SafePasswordH
 
             ICertificatePal? cert;
             Exception? openSslException;
+            bool ephemeralSpecified = keyStorageFlags.HasFlag(X509KeyStorageFlags.EphemeralKeySet);
 
             if (TryReadX509Der(rawData, out cert) ||
                 TryReadX509Pem(rawData, out cert) ||
                 PkcsFormatReader.TryReadPkcs7Der(rawData, out cert) ||
                 PkcsFormatReader.TryReadPkcs7Pem(rawData, out cert) ||
-                PkcsFormatReader.TryReadPkcs12(rawData, password, out cert, out openSslException))
+                PkcsFormatReader.TryReadPkcs12(rawData, password, ephemeralSpecified, out cert, out openSslException))
             {
                 if (cert == null)
                 {
@@ -73,6 +74,7 @@ public static ICertificatePal FromBlob(ReadOnlySpan<byte> rawData, SafePasswordH
         public static ICertificatePal FromFile(string fileName, SafePasswordHandle password, X509KeyStorageFlags keyStorageFlags)
         {
             ICertificatePal? pal;
+            bool ephemeralSpecified = keyStorageFlags.HasFlag(X509KeyStorageFlags.EphemeralKeySet);
 
             // If we can't open the file, fail right away.
             using (SafeBioHandle fileBio = Interop.Crypto.BioNewFile(fileName, "rb"))
@@ -87,6 +89,7 @@ public static ICertificatePal FromFile(string fileName, SafePasswordHandle passw
                 PkcsFormatReader.TryReadPkcs12(
                     File.ReadAllBytes(fileName),
                     password,
+                    ephemeralSpecified,
                     out pal,
                     out Exception? exception);
 

src/libraries/System.Security.Cryptography.X509Certificates/src/Internal/Cryptography/Pal.Unix/PkcsFormatReader.cs

@@ -253,24 +253,49 @@ internal static bool TryReadPkcs7Pem(SafeBioHandle bio, [NotNullWhen(true)] out
             return true;
         }
 
-        internal static bool TryReadPkcs12(ReadOnlySpan<byte> rawData, SafePasswordHandle password, [NotNullWhen(true)] out ICertificatePal? certPal, out Exception? openSslException)
+        internal static bool TryReadPkcs12(
+            ReadOnlySpan<byte> rawData,
+            SafePasswordHandle password,
+            bool ephemeralSpecified,
+            [NotNullWhen(true)] out ICertificatePal? certPal,
+            out Exception? openSslException)
         {
             List<ICertificatePal>? ignored;
 
-            return TryReadPkcs12(rawData, password, true, out certPal!, out ignored, out openSslException);
+            return TryReadPkcs12(
+                rawData,
+                password,
+                single: true,
+                ephemeralSpecified,
+                out certPal!,
+                out ignored,
+                out openSslException);
         }
 
-        internal static bool TryReadPkcs12(ReadOnlySpan<byte> rawData, SafePasswordHandle password, [NotNullWhen(true)] out List<ICertificatePal>? certPals, out Exception? openSslException)
+        internal static bool TryReadPkcs12(
+            ReadOnlySpan<byte> rawData,
+            SafePasswordHandle password,
+            bool ephemeralSpecified,
+            [NotNullWhen(true)] out List<ICertificatePal>? certPals,
+            out Exception? openSslException)
         {
             ICertificatePal? ignored;
 
-            return TryReadPkcs12(rawData, password, false, out ignored, out certPals!, out openSslException);
+            return TryReadPkcs12(
+                rawData,
+                password,
+                single: false,
+                ephemeralSpecified,
+                out ignored,
+                out certPals!,
+                out openSslException);
         }
 
         private static bool TryReadPkcs12(
             ReadOnlySpan<byte> rawData,
             SafePasswordHandle password,
             bool single,
+            bool ephemeralSpecified,
             out ICertificatePal? readPal,
             out List<ICertificatePal>? readCerts,
             out Exception? openSslException)
@@ -287,18 +312,19 @@ internal static bool TryReadPkcs12(ReadOnlySpan<byte> rawData, SafePasswordHandl
 
             using (pfx)
             {
-                return TryReadPkcs12(pfx, password, single, out readPal, out readCerts);
+                return TryReadPkcs12(pfx, password, single, ephemeralSpecified, out readPal, out readCerts);
             }
         }
 
         private static bool TryReadPkcs12(
             OpenSslPkcs12Reader pfx,
             SafePasswordHandle password,
             bool single,
+            bool ephemeralSpecified,
             out ICertificatePal? readPal,
             out List<ICertificatePal>? readCerts)
         {
-            pfx.Decrypt(password);
+            pfx.Decrypt(password, ephemeralSpecified);
 
             if (single)
             {

src/libraries/System.Security.Cryptography.X509Certificates/src/Internal/Cryptography/Pal.Unix/StorePal.cs

@@ -23,6 +23,7 @@ public static ILoaderPal FromBlob(ReadOnlySpan<byte> rawData, SafePasswordHandle
             Debug.Assert(password != null);
 
             ICertificatePal? singleCert;
+            bool ephemeralSpecified = keyStorageFlags.HasFlag(X509KeyStorageFlags.EphemeralKeySet);
 
             if (OpenSslX509CertificateReader.TryReadX509Der(rawData, out singleCert) ||
                 OpenSslX509CertificateReader.TryReadX509Pem(rawData, out singleCert))
@@ -39,7 +40,7 @@ public static ILoaderPal FromBlob(ReadOnlySpan<byte> rawData, SafePasswordHandle
 
             if (PkcsFormatReader.TryReadPkcs7Der(rawData, out certPals) ||
                 PkcsFormatReader.TryReadPkcs7Pem(rawData, out certPals) ||
-                PkcsFormatReader.TryReadPkcs12(rawData, password, out certPals, out openSslException))
+                PkcsFormatReader.TryReadPkcs12(rawData, password, ephemeralSpecified, out certPals, out openSslException))
             {
                 Debug.Assert(certPals != null);
 
@@ -52,15 +53,21 @@ public static ILoaderPal FromBlob(ReadOnlySpan<byte> rawData, SafePasswordHandle
 
         public static ILoaderPal FromFile(string fileName, SafePasswordHandle password, X509KeyStorageFlags keyStorageFlags)
         {
+            bool ephemeralSpecified = keyStorageFlags.HasFlag(X509KeyStorageFlags.EphemeralKeySet);
+
             using (SafeBioHandle bio = Interop.Crypto.BioNewFile(fileName, "rb"))
             {
                 Interop.Crypto.CheckValidOpenSslHandle(bio);
 
-                return FromBio(fileName, bio, password);
+                return FromBio(fileName, bio, password, ephemeralSpecified);
             }
         }
 
-        private static ILoaderPal FromBio(string fileName, SafeBioHandle bio, SafePasswordHandle password)
+        private static ILoaderPal FromBio(
+            string fileName,
+            SafeBioHandle bio,
+            SafePasswordHandle password,
+            bool ephemeralSpecified)
         {
             int bioPosition = Interop.Crypto.BioTell(bio);
             Debug.Assert(bioPosition >= 0);
@@ -104,7 +111,7 @@ private static ILoaderPal FromBio(string fileName, SafeBioHandle bio, SafePasswo
             // Capture the exception so in case of failure, the call to BioSeek does not override it.
             Exception? openSslException;
             byte[] data = File.ReadAllBytes(fileName);
-            if (PkcsFormatReader.TryReadPkcs12(data, password, out certPals, out openSslException))
+            if (PkcsFormatReader.TryReadPkcs12(data, password, ephemeralSpecified, out certPals, out openSslException))
             {
                 return ListToLoaderPal(certPals);
             }

src/libraries/System.Security.Cryptography.X509Certificates/src/Internal/Cryptography/Pal.Unix/UnixPkcs12Reader.cs

@@ -26,6 +26,7 @@ internal abstract class UnixPkcs12Reader : IDisposable
         private CertAndKey[]? _certs;
         private int _certCount;
         private PointerMemoryManager<byte>? _tmpManager;
+        private bool _allowDoubleBind;
 
         protected abstract ICertificatePalCore ReadX509Der(ReadOnlyMemory<byte> data);
         protected abstract AsymmetricAlgorithm LoadKey(ReadOnlyMemory<byte> safeBagBagValue);
@@ -180,11 +181,13 @@ private static void ReturnRentedContentInfos(ContentInfoAsn[] rentedContents)
             ArrayPool<ContentInfoAsn>.Shared.Return(rentedContents, clearArray: true);
         }
 
-        public void Decrypt(SafePasswordHandle password)
+        public void Decrypt(SafePasswordHandle password, bool ephemeralSpecified)
         {
             ReadOnlyMemory<byte> authSafeContents =
                 Helpers.DecodeOctetStringAsMemory(_pfxAsn.AuthSafe.Content);
 
+            _allowDoubleBind = !ephemeralSpecified;
+
             bool hasRef = false;
             password.DangerousAddRef(ref hasRef);
 
@@ -314,6 +317,7 @@ private void Decrypt(ReadOnlySpan<char> password, ReadOnlyMemory<byte> authSafeC
                 ExtractPrivateKeys(password, keyBags, keyBagIdx, keys, publicKeyInfos);
 
                 BuildCertsWithKeys(
+                    password,
                     certBags,
                     certBagAttrs,
                     certs,
@@ -497,6 +501,7 @@ private static ContentInfoAsn[] DecodeSafeContents(ReadOnlyMemory<byte> authSafe
         }
 
         private void BuildCertsWithKeys(
+            ReadOnlySpan<char> password,
             CertBagAsn[] certBags,
             AttributeAsn[]?[] certBagAttrs,
             CertAndKey[] certs,
@@ -550,13 +555,26 @@ private static ContentInfoAsn[] DecodeSafeContents(ReadOnlyMemory<byte> authSafe
 
                 if (matchingKeyIdx != -1)
                 {
+                    // Windows compat:
+                    // If the PFX is loaded with EphemeralKeySet, don't allow double-bind.
+                    // Otherwise, reload the key so a second instance is bound (avoiding one
+                    // cert Dispose removing the key of another).
                     if (keys[matchingKeyIdx] == null)
                     {
-                        throw new CryptographicException(SR.Cryptography_Pfx_BadKeyReference);
+                        if (_allowDoubleBind)
+                        {
+                            certs[certBagIdx].Key = LoadKey(keyBags[matchingKeyIdx], password);
+                        }
+                        else
+                        {
+                            throw new CryptographicException(SR.Cryptography_Pfx_BadKeyReference);
+                        }
+                    }
+                    else
+                    {
+                        certs[certBagIdx].Key = keys[matchingKeyIdx];
+                        keys[matchingKeyIdx] = null;
                     }
-
-                    certs[certBagIdx].Key = keys[matchingKeyIdx];
-                    keys[matchingKeyIdx] = null;
                 }
             }
         }

src/libraries/System.Security.Cryptography.X509Certificates/src/Internal/Cryptography/Pal.iOS/AppleCertificatePal.ImportExport.cs

@@ -103,6 +103,8 @@ internal static X509ContentType GetDerCertContentType(ReadOnlySpan<byte> rawData
         {
             Debug.Assert(password != null);
 
+            bool ephemeralSpecified = keyStorageFlags.HasFlag(X509KeyStorageFlags.EphemeralKeySet);
+
             if (contentType == X509ContentType.Pkcs7)
             {
                 throw new CryptographicException(
@@ -116,7 +118,7 @@ internal static X509ContentType GetDerCertContentType(ReadOnlySpan<byte> rawData
                 // We ignore keyStorageFlags which is tracked in https://github.com/dotnet/runtime/issues/52434.
                 // The keys are always imported as ephemeral and never persisted. Exportability is ignored for
                 // the moment and it needs to be investigated how to map it to iOS keychain primitives.
-                return ImportPkcs12(rawData, password);
+                return ImportPkcs12(rawData, password, ephemeralSpecified);
             }
 
             SafeSecIdentityHandle identityHandle;

src/libraries/System.Security.Cryptography.X509Certificates/src/Internal/Cryptography/Pal.iOS/AppleCertificatePal.Pkcs12.cs

@@ -22,11 +22,12 @@ internal sealed partial class AppleCertificatePal : ICertificatePal
 
         private static AppleCertificatePal ImportPkcs12(
             ReadOnlySpan<byte> rawData,
-            SafePasswordHandle password)
+            SafePasswordHandle password,
+            bool ephemeralSpecified)
         {
             using (ApplePkcs12Reader reader = new ApplePkcs12Reader(rawData))
             {
-                reader.Decrypt(password);
+                reader.Decrypt(password, ephemeralSpecified);
                 return ImportPkcs12(reader.GetSingleCert());
             }
         }

src/libraries/System.Security.Cryptography.X509Certificates/src/Internal/Cryptography/Pal.iOS/StorePal.cs

@@ -37,6 +37,7 @@ public static ILoaderPal FromBlob(ReadOnlySpan<byte> rawData, SafePasswordHandle
                 return new CertCollectionLoader(certificateList);
             }
 
+            bool ephemeralSpecified = keyStorageFlags.HasFlag(X509KeyStorageFlags.EphemeralKeySet);
             X509ContentType contentType = AppleCertificatePal.GetDerCertContentType(rawData);
 
             if (contentType == X509ContentType.Pkcs7)
@@ -52,7 +53,7 @@ public static ILoaderPal FromBlob(ReadOnlySpan<byte> rawData, SafePasswordHandle
 
                 try
                 {
-                    reader.Decrypt(password);
+                    reader.Decrypt(password, ephemeralSpecified);
                     return new ApplePkcs12CertLoader(reader, password);
                 }
                 catch