[CORDA-2225] Use platform's non-blocking PRNG when invoking SecureRandom() (#4234)

core/src/main/kotlin/net/corda/core/crypto/CordaSecurityProvider.kt

@@ -4,6 +4,7 @@ import net.corda.core.KeepForDJVM
 import net.corda.core.StubOutForDJVM
 import net.corda.core.crypto.CordaObjectIdentifier.COMPOSITE_KEY
 import net.corda.core.crypto.CordaObjectIdentifier.COMPOSITE_SIGNATURE
+import net.corda.core.crypto.internal.PlatformSecureRandomService
 import org.bouncycastle.asn1.ASN1ObjectIdentifier
 import java.security.Provider
 
@@ -18,6 +19,12 @@ class CordaSecurityProvider : Provider(PROVIDER_NAME, 0.1, "$PROVIDER_NAME secur
         put("Signature.${CompositeSignature.SIGNATURE_ALGORITHM}", CompositeSignature::class.java.name)
         put("Alg.Alias.Signature.$COMPOSITE_SIGNATURE", CompositeSignature.SIGNATURE_ALGORITHM)
         put("Alg.Alias.Signature.OID.$COMPOSITE_SIGNATURE", CompositeSignature.SIGNATURE_ALGORITHM)
+        putPlatformSecureRandomService()
+    }
+
+    @StubOutForDJVM
+    private fun putPlatformSecureRandomService() {
+        putService(PlatformSecureRandomService(this))
     }
 }
 

core/src/main/kotlin/net/corda/core/crypto/internal/PlatformSecureRandom.kt

@@ -3,16 +3,40 @@
 package net.corda.core.crypto.internal
 
 import net.corda.core.DeleteForDJVM
+import net.corda.core.crypto.newSecureRandom
 import org.apache.commons.lang.SystemUtils
+import java.security.Provider
 import java.security.SecureRandom
+import java.security.SecureRandomSpi
 
 /**
  * This has been migrated into a separate class so that it
  * is easier to delete from the core-deterministic module.
  */
-internal val platformSecureRandom: () -> SecureRandom = when {
+val platformSecureRandom: () -> SecureRandom = when {
     SystemUtils.IS_OS_LINUX -> {
         { SecureRandom.getInstance("NativePRNGNonBlocking") }
     }
     else -> SecureRandom::getInstanceStrong
 }
+
+@DeleteForDJVM
+class PlatformSecureRandomService(provider: Provider)
+    : Provider.Service(provider, "SecureRandom", algorithm, PlatformSecureRandomSpi::javaClass.name, null, null) {
+
+    companion object {
+        const val algorithm = "CordaPRNG"
+    }
+
+    private val instance: SecureRandomSpi = PlatformSecureRandomSpi()
+    override fun newInstance(constructorParameter: Any?) = instance
+}
+
+@DeleteForDJVM
+private class PlatformSecureRandomSpi : SecureRandomSpi() {
+    private val secureRandom: SecureRandom = newSecureRandom()
+
+    override fun engineSetSeed(seed: ByteArray) = secureRandom.setSeed(seed)
+    override fun engineNextBytes(bytes: ByteArray) = secureRandom.nextBytes(bytes)
+    override fun engineGenerateSeed(numBytes: Int): ByteArray = secureRandom.generateSeed(numBytes)
+}

core/src/main/kotlin/net/corda/core/crypto/internal/ProviderMap.kt

@@ -18,12 +18,18 @@ import org.bouncycastle.pqc.jcajce.provider.BouncyCastlePQCProvider
 import java.security.SecureRandom
 import java.security.Security
 
-internal val cordaSecurityProvider = CordaSecurityProvider().also {
+val cordaSecurityProvider = CordaSecurityProvider().also {
+    // Among the others, we should register [CordaSecurityProvider] as the first provider, to ensure that when invoking [SecureRandom()]
+    // the [platformSecureRandom] is returned (which is registered in CordaSecurityProvider).
+    // Note that internally, [SecureRandom()] will look through all registered providers.
+    // Then it returns the first PRNG algorithm of the first provider that has registered a SecureRandom
+    // implementation (in our case [CordaSecurityProvider]), or null if none of the registered providers supplies
+    // a SecureRandom implementation.
     Security.insertProviderAt(it, 1) // The position is 1-based.
 }
 // OID taken from https://tools.ietf.org/html/draft-ietf-curdle-pkix-00
-internal val `id-Curve25519ph` = ASN1ObjectIdentifier("1.3.101.112")
-internal val cordaBouncyCastleProvider = BouncyCastleProvider().apply {
+val `id-Curve25519ph` = ASN1ObjectIdentifier("1.3.101.112")
+val cordaBouncyCastleProvider = BouncyCastleProvider().apply {
     putAll(EdDSASecurityProvider())
     // Override the normal EdDSA engine with one which can handle X509 keys.
     put("Signature.${EdDSAEngine.SIGNATURE_ALGORITHM}", X509EdDSAEngine::class.java.name)
@@ -38,7 +44,7 @@ internal val cordaBouncyCastleProvider = BouncyCastleProvider().apply {
     // TODO: Find a way to make JKS work with bouncy castle provider or implement our own provide so we don't have to register bouncy castle provider.
     Security.addProvider(it)
 }
-internal val bouncyCastlePQCProvider = BouncyCastlePQCProvider().apply {
+val bouncyCastlePQCProvider = BouncyCastlePQCProvider().apply {
     require(name == "BCPQC") // The constant it comes from is not final.
 }.also {
     Security.addProvider(it)
@@ -47,7 +53,7 @@ internal val bouncyCastlePQCProvider = BouncyCastlePQCProvider().apply {
 // that could cause unexpected and suspicious behaviour.
 // i.e. if someone removes a Provider and then he/she adds a new one with the same name.
 // The val is private to avoid any harmful state changes.
-internal val providerMap = listOf(cordaBouncyCastleProvider, cordaSecurityProvider, bouncyCastlePQCProvider).map { it.name to it }.toMap()
+val providerMap = listOf(cordaBouncyCastleProvider, cordaSecurityProvider, bouncyCastlePQCProvider).map { it.name to it }.toMap()
 
 @DeleteForDJVM
-internal fun platformSecureRandomFactory(): SecureRandom = platformSecureRandom() // To minimise diff of CryptoUtils against open-source.
+fun platformSecureRandomFactory(): SecureRandom = platformSecureRandom() // To minimise diff of CryptoUtils against open-source.

core/src/test/kotlin/net/corda/core/crypto/CryptoUtilsTest.kt

@@ -6,6 +6,7 @@ import net.corda.core.crypto.Crypto.ECDSA_SECP256R1_SHA256
 import net.corda.core.crypto.Crypto.EDDSA_ED25519_SHA512
 import net.corda.core.crypto.Crypto.RSA_SHA256
 import net.corda.core.crypto.Crypto.SPHINCS256_SHA256
+import net.corda.core.crypto.internal.PlatformSecureRandomService
 import net.corda.core.utilities.OpaqueBytes
 import net.i2p.crypto.eddsa.EdDSAKey
 import net.i2p.crypto.eddsa.EdDSAPrivateKey
@@ -16,10 +17,7 @@ import net.i2p.crypto.eddsa.spec.EdDSANamedCurveTable
 import net.i2p.crypto.eddsa.spec.EdDSAPublicKeySpec
 import org.apache.commons.lang.ArrayUtils.EMPTY_BYTE_ARRAY
 import org.bouncycastle.asn1.pkcs.PrivateKeyInfo
-import org.bouncycastle.asn1.x500.X500Name
 import org.bouncycastle.asn1.x509.SubjectPublicKeyInfo
-import org.bouncycastle.cert.jcajce.JcaX509CertificateConverter
-import org.bouncycastle.cert.jcajce.JcaX509v3CertificateBuilder
 import org.bouncycastle.jcajce.provider.asymmetric.ec.BCECPrivateKey
 import org.bouncycastle.jcajce.provider.asymmetric.ec.BCECPublicKey
 import org.bouncycastle.jce.ECNamedCurveTable
@@ -31,9 +29,9 @@ import org.bouncycastle.pqc.jcajce.provider.sphincs.BCSphincs256PublicKey
 import org.junit.Assert.assertNotEquals
 import org.junit.Test
 import java.math.BigInteger
-import java.security.KeyPair
 import java.security.KeyPairGenerator
-import java.security.cert.X509Certificate
+import java.security.SecureRandom
+import java.security.Security
 import java.util.*
 import kotlin.test.*
 
@@ -934,26 +932,25 @@ class CryptoUtilsTest {
         this.outputStream.close()
     }
 
-    private fun createCert(signer: ContentSigner, keyPair: KeyPair): X509Certificate {
-        val dname = X500Name("CN=TestEntity")
-        val startDate = Calendar.getInstance().let { cal ->
-            cal.time = Date()
-            cal.add(Calendar.HOUR, -1)
-            cal.time
-        }
-        val endDate = Calendar.getInstance().let { cal ->
-            cal.time = startDate
-            cal.add(Calendar.YEAR, 1)
-            cal.time
-        }
-        val certificate = JcaX509v3CertificateBuilder(
-                dname,
-                BigInteger.TEN,
-                startDate,
-                endDate,
-                dname,
-                keyPair.public
-        ).build(signer)
-        return JcaX509CertificateConverter().getCertificate(certificate)
+    @Test
+    fun `test default SecureRandom uses platformSecureRandom`() {
+        // Note than in Corda, [CordaSecurityProvider] is registered as the first provider.
+
+        // Remove [CordaSecurityProvider] in case it is already registered.
+        Security.removeProvider(CordaSecurityProvider.PROVIDER_NAME)
+        // Try after removing CordaSecurityProvider.
+        val secureRandomNotRegisteredCordaProvider = SecureRandom()
+        assertNotEquals(PlatformSecureRandomService.algorithm, secureRandomNotRegisteredCordaProvider.algorithm)
+
+        // Now register CordaSecurityProvider as last Provider.
+        Security.addProvider(CordaSecurityProvider())
+        val secureRandomRegisteredLastCordaProvider = SecureRandom()
+        assertNotEquals(PlatformSecureRandomService.algorithm, secureRandomRegisteredLastCordaProvider.algorithm)
+
+        // Remove Corda Provider again and add it as the first Provider entry.
+        Security.removeProvider(CordaSecurityProvider.PROVIDER_NAME)
+        Security.insertProviderAt(CordaSecurityProvider(), 1) // This is base-1.
+        val secureRandomRegisteredFirstCordaProvider = SecureRandom()
+        assertEquals(PlatformSecureRandomService.algorithm, secureRandomRegisteredFirstCordaProvider.algorithm)
     }
 }