Cleanup/alg specific foo

crypto/src/commonMain/kotlin/at/asitplus/awesn1/crypto/EcdsaSigValue.kt

@@ -0,0 +1,19 @@
+// SPDX-FileCopyrightText: Copyright (c) A-SIT Plus GmbH
+// SPDX-License-Identifier: Apache-2.0
+
+package at.asitplus.awesn1.crypto
+
+import at.asitplus.awesn1.Asn1Integer
+import at.asitplus.awesn1.serialization.DER
+import at.asitplus.awesn1.serialization.decodeFromDer
+import kotlinx.serialization.Serializable
+import kotlinx.serialization.encodeToByteArray
+
+@Serializable
+data class EcdsaSigValue(val r: Asn1Integer, val s: Asn1Integer) {
+    fun toX509SignatureValue() = X509SignatureValue(DER.encodeToByteArray(this))
+    companion object {
+        fun X509SignatureValue.toEcdsaSigValue() = DER.decodeFromDer<EcdsaSigValue>(rawBytes)
+    }
+}
+

crypto/src/commonMain/kotlin/at/asitplus/awesn1/crypto/RsaSsaPssParams.kt

@@ -3,11 +3,15 @@
 
 package at.asitplus.awesn1.crypto
 
+import at.asitplus.awesn1.Asn1Exception
 import at.asitplus.awesn1.Asn1Integer
 import at.asitplus.awesn1.ObjectIdentifier
 import at.asitplus.awesn1.encoding.Asn1
+import at.asitplus.awesn1.runRethrowing
 import at.asitplus.awesn1.serialization.Asn1Tag
+import at.asitplus.awesn1.serialization.DER
 import at.asitplus.awesn1.serialization.ExplicitlyTagged
+import at.asitplus.awesn1.serialization.decodeFromTlv
 import at.asitplus.awesn1.serialization.getValue
 import at.asitplus.awesn1.toInt
 import kotlinx.serialization.Serializable
@@ -117,6 +121,23 @@ data class RsaSsaPssParams internal constructor(
 
         val SHA1_IDENTIFIER = X509AlgorithmIdentifier(SHA1_OID, listOf(Asn1.Null()))
         val MGF1_SHA1_IDENTIFIER = X509AlgorithmIdentifier(MGF1_OID, listOf(SHA1_IDENTIFIER.element))
+
+        /**
+         * Asserts that this identifier uses the `id-RSASSA-PSS` OID,
+         * then parses [parameters] as RSASSA-PSS parameters.
+         *
+         * This helper models [RFC 4055, section 3.1](https://www.rfc-editor.org/rfc/rfc4055.html#section-3.1).
+         *
+         * @throws Asn1Exception if this algorithm is RSA_SSA_PSS has no parameters, or the parameter element is
+         * not a valid `RSASSA-PSS-params` SEQUENCE.
+         */
+        val X509AlgorithmIdentifier.rsaSsaPssParams: RsaSsaPssParams get() = runRethrowing {
+            require(oid == RSA_SSA_PSS_OID)
+            DER.decodeFromTlv<RsaSsaPssParams>(
+                parameters?.asSequence() ?: throw Asn1Exception("RSASSA-PSS AlgorithmIdentifier has no parameters")
+            )
+        }
+
     }
 
     override fun equals(other: Any?): Boolean {

crypto/src/commonMain/kotlin/at/asitplus/awesn1/crypto/X509AlgorithmIdentifier.kt

@@ -87,35 +87,6 @@ value class X509AlgorithmIdentifier(override val element: Asn1Sequence) : Identi
             else -> throw Asn1Exception("AlgorithmIdentifier has ${element.children.size} children")
         }
 
-    /**
-     * Parses [parameters] as RSASSA-PSS parameters if this identifier uses the `id-RSASSA-PSS` OID.
-     *
-     * This helper models [RFC 4055, section 3.1](https://www.rfc-editor.org/rfc/rfc4055.html#section-3.1) without
-     * making [X509AlgorithmIdentifier] itself enforce algorithm-specific parameter schemas during generic DER parsing.
-     *
-     * @return `null` if this algorithm is nor RSA_SSA_PSS
-     *
-     * @throws Asn1Exception if this algorithm is RSA_SSA_PSS has no parameters, or the parameter element is
-     * not a valid `RSASSA-PSS-params` SEQUENCE.
-     *
-     * From Swift/Objective-C use the throwing `rsaSsaPssParams()` accessor (exported as a static
-     * `rsaSsaPssParams(_:)`, since value classes are not bridged as Objective-C types).
-     */
-    @OptIn(ExperimentalObjCRefinement::class)
-    @Suppress("WRONG_ANNOTATION_TARGET_WITH_USE_SITE_TARGET")
-    @get:Throws(Asn1Exception::class)
-    @HiddenFromObjC
-    @get:HiddenFromObjC
-    val rsaSsaPssParams: RsaSsaPssParams?
-        get() = runWrappingAs(a = ::Asn1Exception) {
-            if (oid != RsaSsaPssParams.RSA_SSA_PSS_OID) {
-                return null
-            }
-            DER.decodeFromTlv<RsaSsaPssParams>(
-                parameters?.asSequence() ?: throw Asn1Exception("RSASSA-PSS AlgorithmIdentifier has no parameters")
-            )
-        }
-
     override fun toString(): String {
         return catchingUnwrapped {
             "AlgorithmIdentifier(" +

crypto/src/commonMain/kotlin/at/asitplus/awesn1/crypto/X509SignatureValue.kt

@@ -49,21 +49,4 @@ value class X509SignatureValue(val rawBitString: Asn1BitString): WrappedEncodabl
     constructor(rawBytes: ByteArray) : this(Asn1BitString(rawBytes))
 
     val rawBytes: ByteArray get() = rawBitString.bitCarryingBytes
-
-    // runRethrowing: a malformed ECDSA-Sig-Value (fewer than two children, or non-positive integers) would
-    // otherwise leak NoSuchElementException/ClassCastException instead of a catchable Asn1Exception.
-    @Throws(Asn1Exception::class)
-    fun decodeRS(): Pair<Asn1Integer.Positive, Asn1Integer.Positive> = runRethrowing {
-        Asn1Element.parse(rawBytes).asSequence().decodeAs {
-            next().asPrimitive().decodeToAsn1Integer() as Asn1Integer.Positive to
-                next().asPrimitive().decodeToAsn1Integer() as Asn1Integer.Positive
-        }
-    }
-
-    companion object {
-        fun fromRS(r: Asn1Integer.Positive, s: Asn1Integer.Positive) =
-            X509SignatureValue(Asn1.Sequence { +r; +s }.derEncoded)
-    }
 }
-
-fun X509SignatureValue.decodeRsOrNull() = catchingUnwrapped { decodeRS() }.getOrNull()

crypto/src/commonTest/kotlin/at/asitplus/awesn1/crypto/CryptoDerRoundTripTest.kt

@@ -84,7 +84,7 @@ private fun randomBitStringSignatureValue(random: Random) =
     X509SignatureValue(randomBytes(random))
 
 private fun randomEcdsaSignatureValue(random: Random) =
-    X509SignatureValue.fromRS(positiveAsn1Integer(random), positiveAsn1Integer(random))
+    EcdsaSigValue(positiveAsn1Integer(random), positiveAsn1Integer(random)).toX509SignatureValue()
 
 private fun randomEcPrivateKey(random: Random) = Sec1EcPrivateKeyInfo(
     privateKey = randomBytes(random, 32),

crypto/src/commonTest/kotlin/at/asitplus/awesn1/crypto/EcdsaSigValueTest.kt

@@ -0,0 +1,21 @@
+package at.asitplus.awesn1.crypto
+
+import at.asitplus.awesn1.Asn1Integer
+import at.asitplus.awesn1.crypto.EcdsaSigValue.Companion.toEcdsaSigValue
+import at.asitplus.awesn1.serialization.DER
+import at.asitplus.awesn1.serialization.decodeFromDer
+import at.asitplus.testballoon.matrix.matrixSuite
+import io.kotest.matchers.shouldBe
+import kotlin.io.encoding.Base64
+
+val EcdsaSigValueTest by matrixSuite {
+    "Test" {
+        val sigValue = Base64.UrlSafe.decode("A0kAMEYCIQCnXiAKLwJP0uXBKtTmJccBu" +
+            "yddhFFVTz-J0DNHBi21lgIhAI1SUoIYXXqdZMrKox4_HBTEmuxvG9sloAoDH5rfsyd4")
+            .let { DER.decodeFromDer<X509SignatureValue>(it) }
+        sigValue.toEcdsaSigValue().let {
+            it.r.toString() shouldBe "75702550467927847687504835259358957068594330833158195591194084637648375100822"
+            it.s.toString() shouldBe "63921562560111841846899158949481573510824775155107323853077162713843342976888"
+        }
+    }
+}