Allows to seed extra random bytes (#509)

Fixes korlibs-archive/krypto#12
korlibs-archive · Mar 20, 2022 · 228e0c8 · 228e0c8
1 parent b32d449
commit 228e0c8
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Showing 7 changed files with 44 additions and 8 deletions.
diff --git a/krypto/src/androidMain/kotlin/com/soywiz/krypto/SecureRandomJvm.kt b/krypto/src/androidMain/kotlin/com/soywiz/krypto/SecureRandomJvm.kt
@@ -13,3 +13,6 @@ actual fun fillRandomBytes(array: ByteArray) {
     jrandom.nextBytes(array)
 }
 
+actual fun seedExtraRandomBytes(array: ByteArray) {
+    jrandom.setSeed(array)
+}
diff --git a/krypto/src/commonMain/kotlin/com/soywiz/krypto/SecureRandom.kt b/krypto/src/commonMain/kotlin/com/soywiz/krypto/SecureRandom.kt
@@ -4,9 +4,13 @@ import com.soywiz.krypto.internal.arraycopy
 import kotlin.random.Random
 
 expect fun fillRandomBytes(array: ByteArray)
+expect fun seedExtraRandomBytes(array: ByteArray)
 var randomUnittesting = false
 
 object SecureRandom : Random() {
+    fun addSeed(array: ByteArray) {
+        seedExtraRandomBytes(array)
+    }
 
     private fun getInt(): Int {
         val temp = ByteArray(4)

diff --git a/krypto/src/commonTest/kotlin/com/soywiz/krypto/SecureRandomTest.kt b/krypto/src/commonTest/kotlin/com/soywiz/krypto/SecureRandomTest.kt
@@ -7,6 +7,7 @@ class SecureRandomTest {
     @Test
     fun test() {
         randomUnittesting = true // Required for android not mocking some stuff required for PRNGFixes
+        SecureRandom.addSeed(byteArrayOf(1, 2, 3)) // This shouldn't reduce entropy
         println(SecureRandom.nextBytes(15).toList())
         println(SecureRandom.nextBytes(15).toList())
         assertNotEquals(SecureRandom.nextBytes(16).toList(), SecureRandom.nextBytes(16).toList())

diff --git a/krypto/src/jsMain/kotlin/com/soywiz/krypto/SecureRandomJs.kt b/krypto/src/jsMain/kotlin/com/soywiz/krypto/SecureRandomJs.kt
@@ -16,8 +16,14 @@ private fun require_node(name: String): dynamic = eval("(${REQ}uire('$name'))")
 
 actual fun fillRandomBytes(array: ByteArray) {
     if (isNodeJs) {
+        // https://nodejs.org/api/crypto.html#cryptorandomfillsyncbuffer-offset-size
         require_node("crypto").randomFillSync(Uint8Array(array.unsafeCast<Int8Array>().buffer))
     } else {
+        // https://developer.mozilla.org/en-US/docs/Web/API/Crypto/getRandomValues
         _global.crypto.getRandomValues(array)
     }
 }
+
+actual fun seedExtraRandomBytes(array: ByteArray) {
+    // No implementation for this?
+}
diff --git a/krypto/src/jvmMain/kotlin/com/soywiz/krypto/SecureRandomJvm.kt b/krypto/src/jvmMain/kotlin/com/soywiz/krypto/SecureRandomJvm.kt
@@ -7,3 +7,7 @@ private val jrandom = SecureRandom()
 actual fun fillRandomBytes(array: ByteArray) {
     jrandom.nextBytes(array)
 }
+
+actual fun seedExtraRandomBytes(array: ByteArray) {
+    jrandom.setSeed(array)
+}
diff --git a/krypto/src/mingwMain/kotlin/com/soywiz/krypto/SecureRandomNativeWin32.kt b/krypto/src/mingwMain/kotlin/com/soywiz/krypto/SecureRandomNativeWin32.kt
@@ -12,11 +12,14 @@ private val BCryptGenRandomDynamic by lazy {
 }
 
 actual fun fillRandomBytes(array: ByteArray) {
-    memScoped {
-        val temp1 = allocArray<ByteVar>(array.size)
-        val ptr = temp1.getPointer(this)
+    if (array.size == 0) return
+
+    array.usePinned { pin ->
+        val ptr = pin.addressOf(0)
         val status = BCryptGenRandomDynamic(null, ptr.reinterpret(), array.size.convert(), 2.convert())
-        //println("status = $status")
-        for (n in 0 until array.size) array[n] = ptr[n]
     }
 }
+
+actual fun seedExtraRandomBytes(array: ByteArray) {
+    // No implementation for this?
+}
diff --git a/krypto/src/posixInteropMain/kotlin/com/soywiz/krypto/SecureRandomNativePosix.kt b/krypto/src/posixInteropMain/kotlin/com/soywiz/krypto/SecureRandomNativePosix.kt
@@ -4,9 +4,10 @@ import kotlinx.cinterop.*
 import platform.posix.*
 
 actual fun fillRandomBytes(array: ByteArray) {
-    memScoped {
-        val temp1 = allocArray<ByteVar>(1024)
-        val ptr = temp1.getPointer(this)
+    if (array.isEmpty()) return
+
+    array.usePinned { pin ->
+        val ptr = pin.addressOf(0)
         val file = fopen("/dev/urandom", "rb")
         if (file != null) {
             fread(ptr, 1.convert(), array.size.convert(), file)
@@ -15,3 +16,17 @@ actual fun fillRandomBytes(array: ByteArray) {
         }
     }
 }
+
+actual fun seedExtraRandomBytes(array: ByteArray) {
+    if (array.isEmpty()) return
+
+    array.usePinned { pin ->
+        val ptr = pin.addressOf(0)
+        val file = fopen("/dev/urandom", "wb")
+        if (file != null) {
+            fwrite(ptr, 1.convert(), array.size.convert(), file)
+            for (n in 0 until array.size) array[n] = ptr[n]
+            fclose(file)
+        }
+    }
+}