Add key reader function impl to default keystore on Linux

kmp-advcrypto/src/commonMain/kotlin/io/karma/advcrypto/algorithm/delegates/KeyStoreFactory.kt

@@ -32,7 +32,7 @@ import okio.Path
  */
 class KeyStoreFactory<C: Any>(val name: String) {
     private lateinit var initialize: () -> C
-    private var readKeyFromFile: ((C, Path) -> Key)? = null
+    private var readKeyFromFile: ((C, Path, String, UByte) -> Key)? = null
 
     /**
      * This method creates a new keystore with the delegate functions specified and initializes the
@@ -45,18 +45,9 @@ class KeyStoreFactory<C: Any>(val name: String) {
      */
     fun createKeyStore(): KeyStore = object: KeyStore {
         private val context = initialize()
-
-        /**
-         * This method opens the file with `okio` and reads the content as a bytearray. This content
-         * is used to extract information from the key and return this key to the user.
-         *
-         * @param path The path of the file
-         * @return     The key derived from the file
-         *
-         * @author Cedric Hammes
-         * @since  14/06/2024
-         */
-        override fun readKeyFromFile(path: Path): Key = readKeyFromFile!!.invoke(context, path)
+
+        override fun readKeyFromFile(path: Path, algorithm: String, purposes: UByte): Key =
+            readKeyFromFile!!.invoke(context, path, algorithm, purposes)
     }
 
     /**
@@ -75,7 +66,7 @@ class KeyStoreFactory<C: Any>(val name: String) {
      * @author Cedric Hammes
      * @since  14/06/2024
      */
-    fun readKeyFromFile(closure: (C, Path) -> Key) = this.apply {
+    fun readKeyFromFile(closure: (C, Path, String, UByte) -> Key) = this.apply {
         if (readKeyFromFile != null)
             throw IllegalStateException("Unable to set readKeyFromFile delegate twice")
         readKeyFromFile = closure

kmp-advcrypto/src/commonMain/kotlin/io/karma/advcrypto/wrapper/KeyStore.kt

@@ -35,13 +35,15 @@ interface KeyStore {
      * This method opens the file with `okio` and reads the content as a bytearray. This content is
      * used to extract information from the key and return this key to the user.
      *
-     * @param path The path of the file
-     * @return     The key derived from the file
+     * @param path      The path of the file
+     * @param algorithm The name of the key's algorithm
+     * @param purposes  The purposes of the key
+     * @return          The key derived from the file
      *
      * @author Cedric Hammes
      * @since  14/06/2024
      */
-    fun readKeyFromFile(path: Path): Key
+    fun readKeyFromFile(path: Path, algorithm: String, purposes: UByte): Key
 
     companion object {
         /**

kmp-advcrypto/src/linuxX64Main/kotlin/io/karma/advcrypto/linux/keys/OpenSSLKey.kt

@@ -41,7 +41,7 @@ class OpenSSLKey(private val secureHeap: SecureHeap,
 ): Key {
     @InsecureCryptoApi
     override val encoded: ByteArray = ByteArray(rawDataSize.toInt()) { rawDataPtr[it].toByte() }
-    override val format: KeyFormat = KeyFormat.DER // TODO: Derive from encoded content
+    override val format: KeyFormat = KeyFormat.DER // TODO: Derive from key
 
     override fun close() {
         secureHeap.free(rawDataSize, rawDataPtr)

kmp-advcrypto/src/linuxX64Main/kotlin/io/karma/advcrypto/linux/providers/DefaultKeyStoreProvider.kt

@@ -18,6 +18,7 @@ package io.karma.advcrypto.linux.providers
 
 import io.karma.advcrypto.AbstractProvider
 import io.karma.advcrypto.Providers
+import io.karma.advcrypto.linux.utils.KeyReaderHelper
 import okio.FileSystem
 
 class DefaultKeyStoreProvider: AbstractProvider(
@@ -30,12 +31,14 @@ class DefaultKeyStoreProvider: AbstractProvider(
             initialize {
                 "Placeholder"
             }
-            readKeyFromFile { context, path ->
+            readKeyFromFile { _, path, algorithm, purposes ->
                 FileSystem.SYSTEM.read(path) {
                     val data = readByteArray()
                     close()
+                    return@readKeyFromFile KeyReaderHelper.tryParse(data, purposes, algorithm)?:
+                    throw RuntimeException("Unable to parse key, no valid format!")
+
                 }
-                TODO("Read and derive key")
             }
         }
     }

kmp-advcrypto/src/linuxX64Main/kotlin/io/karma/advcrypto/linux/utils/KeyReaderHelper.kt

@@ -191,8 +191,11 @@ object KeyReaderHelper {
      * @author Cedric Hammes
      * @since  14/06/2024
      */
-    fun tryParse(array: ByteArray, purposes: UByte): Key? = array.usePinned {
-        tryParse(it.addressOf(0), array.size.toULong(), purposes)
+    fun tryParse(array: ByteArray, purposes: UByte, algorithm: String? = null): Key? = array.usePinned {
+        val parsedKey = tryParse(it.addressOf(0), array.size.toULong(), purposes)?: return null
+        if (parsedKey.algorithm != algorithm)
+            throw IllegalArgumentException("The algorithm '$algorithm' was specified, but key is '${parsedKey.algorithm}'")
+        return parsedKey
     }
 
 }