kn: checksum bindings (#121)

Author: lauzadis

aws-crt-kotlin/native/src/aws/sdk/kotlin/crt/WithCrt.kt

@@ -0,0 +1,14 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+package aws.sdk.kotlin.crt
+
+/**
+ * A mixin class used to ensure CRT is initialized before the class is invoked
+ */
+public open class WithCrt {
+    init {
+        CRT.initRuntime { }
+    }
+}

aws-crt-kotlin/native/src/aws/sdk/kotlin/crt/util/DigestNative.kt

@@ -2,10 +2,9 @@
  * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
  * SPDX-License-Identifier: Apache-2.0
  */
-
 package aws.sdk.kotlin.crt.util
 
-import Sha256
+import aws.sdk.kotlin.crt.util.hashing.Sha256
 
 /**
  * Utility object for various hash functions

aws-crt-kotlin/native/src/aws/sdk/kotlin/crt/util/hashing/CrcNative.kt

@@ -2,6 +2,9 @@
  * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
  * SPDX-License-Identifier: Apache-2.0
  */
+package aws.sdk.kotlin.crt.util.hashing
+
+import aws.sdk.kotlin.crt.WithCrt
 import kotlinx.cinterop.*
 import libcrt.aws_checksums_crc32
 import libcrt.aws_checksums_crc32c
@@ -21,6 +24,10 @@ internal class Crc(val checksumFn: AwsChecksumsCrcFunction) : HashFunction {
     private var crc = 0U
 
     override fun update(input: ByteArray, offset: Int, length: Int) {
+        if (input.isEmpty() || length == 0) {
+            return
+        }
+
         val offsetInput = input.usePinned {
             it.addressOf(offset)
         }
@@ -42,7 +49,9 @@ internal class Crc(val checksumFn: AwsChecksumsCrcFunction) : HashFunction {
 /**
  * A CRC32 [HashFunction] implemented using bindings to CRT.
  */
-public class Crc32 : HashFunction {
+public class Crc32 :
+    WithCrt(),
+    HashFunction {
     private val crc32 = Crc(::aws_checksums_crc32)
     override fun update(input: ByteArray, offset: Int, length: Int) {
         crc32.update(input, offset, length)
@@ -56,7 +65,9 @@ public class Crc32 : HashFunction {
 /**
  * A CRC32C [HashFunction] implemented using bindings to CRT.
  */
-public class Crc32c : HashFunction {
+public class Crc32c :
+    WithCrt(),
+    HashFunction {
     private val crc32c = Crc(::aws_checksums_crc32c)
     override fun update(input: ByteArray, offset: Int, length: Int) {
         crc32c.update(input, offset, length)

aws-crt-kotlin/native/src/aws/sdk/kotlin/crt/util/hashing/HashFunctionNative.kt

@@ -2,6 +2,8 @@
  * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
  * SPDX-License-Identifier: Apache-2.0
  */
+package aws.sdk.kotlin.crt.util.hashing
+
 /**
  * A function which calculates the hash of given data
  */

aws-crt-kotlin/native/src/aws/sdk/kotlin/crt/util/hashing/Md5Native.kt

@@ -0,0 +1,65 @@
+/*
+ * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
+ * SPDX-License-Identifier: Apache-2.0
+ */
+package aws.sdk.kotlin.crt.util.hashing
+
+import aws.sdk.kotlin.crt.Allocator
+import aws.sdk.kotlin.crt.WithCrt
+import aws.sdk.kotlin.crt.awsAssertOpSuccess
+import kotlinx.cinterop.addressOf
+import kotlinx.cinterop.cValue
+import kotlinx.cinterop.convert
+import kotlinx.cinterop.pointed
+import kotlinx.cinterop.reinterpret
+import kotlinx.cinterop.usePinned
+import libcrt.aws_byte_buf
+import libcrt.aws_byte_cursor_from_array
+import libcrt.aws_hash_destroy
+import libcrt.aws_hash_finalize
+import libcrt.aws_hash_update
+import libcrt.aws_md5_new
+
+/**
+ * MD5 hash function implemented using bindings to CRT
+ */
+public class Md5 :
+    WithCrt(),
+    HashFunction {
+    private var md5 = checkNotNull(aws_md5_new(Allocator.Default)) { "aws_md5_new" }
+
+    override fun update(input: ByteArray, offset: Int, length: Int) {
+        if (input.isEmpty() || length == 0) {
+            return
+        }
+
+        val inputCursor = input.usePinned {
+            aws_byte_cursor_from_array(it.addressOf(offset), length.convert())
+        }
+
+        awsAssertOpSuccess(aws_hash_update(md5, inputCursor)) {
+            "aws_hash_update"
+        }
+    }
+
+    override fun digest(): ByteArray {
+        val output = ByteArray(md5.pointed.digest_size.toInt())
+
+        val byteBuf = output.usePinned {
+            cValue<aws_byte_buf> {
+                capacity = output.size.convert()
+                len = 0U
+                buffer = it.addressOf(0).reinterpret()
+            }
+        }
+
+        awsAssertOpSuccess(aws_hash_finalize(md5, byteBuf, 0U)) { "aws_hash_finalize" }
+
+        return output.also { reset() }
+    }
+
+    override fun reset() {
+        aws_hash_destroy(md5)
+        md5 = checkNotNull(aws_md5_new(Allocator.Default)) { "aws_md5_new" }
+    }
+}

aws-crt-kotlin/native/src/aws/sdk/kotlin/crt/util/hashing/ShaNative.kt

@@ -2,7 +2,10 @@
  * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
  * SPDX-License-Identifier: Apache-2.0
  */
+package aws.sdk.kotlin.crt.util.hashing
+
 import aws.sdk.kotlin.crt.Allocator
+import aws.sdk.kotlin.crt.WithCrt
 import aws.sdk.kotlin.crt.awsAssertOpSuccess
 import kotlinx.cinterop.*
 import libcrt.*
@@ -17,7 +20,9 @@ internal typealias InitializeHashFn = (
 /**
  * SHA-1 hash function implemented using bindings to CRT
  */
-public class Sha1 : HashFunction {
+public class Sha1 :
+    WithCrt(),
+    HashFunction {
     private val sha1 = Sha(::aws_sha1_new)
     override fun update(input: ByteArray, offset: Int, length: Int) {
         sha1.update(input, offset, length)
@@ -31,7 +36,9 @@ public class Sha1 : HashFunction {
 /**
  * SHA-256 hash function implemented using bindings to CRT
  */
-public class Sha256 : HashFunction {
+public class Sha256 :
+    WithCrt(),
+    HashFunction {
     private val sha256 = Sha(::aws_sha256_new)
     override fun update(input: ByteArray, offset: Int, length: Int) {
         sha256.update(input, offset, length)
@@ -51,6 +58,10 @@ internal class Sha(val initializeFn: InitializeHashFn) : HashFunction {
 
     // aws_hash_update
     override fun update(input: ByteArray, offset: Int, length: Int) {
+        if (input.isEmpty() || length == 0) {
+            return
+        }
+
         val inputCursor = input.usePinned {
             aws_byte_cursor_from_array(it.addressOf(offset), length.convert())
         }

aws-crt-kotlin/native/test/aws/sdk/kotlin/crt/util/hashing/HashFunctionNativeTest.kt

@@ -2,6 +2,8 @@
  * Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
  * SPDX-License-Identifier: Apache-2.0
  */
+package aws.sdk.kotlin.crt.util.hashing
+
 import aws.sdk.kotlin.crt.util.encodeToHex
 import kotlin.test.Test
 import kotlin.test.assertEquals
@@ -48,4 +50,21 @@ class HashFunctionTest {
             assertEquals(expected, hash.digest().encodeToHex())
         }
     }
+
+    @Test
+    fun testEmptyUpdate() {
+        // algorithm -> hash("")
+        val tests = listOf(
+            (Sha1() to "da39a3ee5e6b4b0d3255bfef95601890afd80709"),
+            (Sha256() to "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855"),
+            (Crc32() to "00000000"),
+            (Crc32c() to "00000000"),
+        )
+
+        tests.forEach { (hash, expected) ->
+            val data = "".encodeToByteArray()
+            hash.update(data, 0, 0)
+            assertEquals(expected, hash.digest().encodeToHex())
+        }
+    }
 }

gradle/libs.versions.toml

@@ -1,7 +1,7 @@
 [versions]
 kotlin-version = "2.0.21"
 
-aws-kotlin-repo-tools-version = "0.4.14-kn"
+aws-kotlin-repo-tools-version = "0.4.16-kn"
 
 # libs
 crt-java-version = "0.31.3"