feat: add SHA256-HMAC for use in build-in pseudonym generator (#324)

6 files changed, 147 insertions, 49 deletions

diff --git a/src/integrationTest/kotlin/dev/dnpm/etl/processor/config/AppConfigurationTest.kt b/src/integrationTest/kotlin/dev/dnpm/etl/processor/config/AppConfigurationTest.kt
index f2bfd90..99ef0a2 100644
--- a/src/integrationTest/kotlin/dev/dnpm/etl/processor/config/AppConfigurationTest.kt
+++ b/src/integrationTest/kotlin/dev/dnpm/etl/processor/config/AppConfigurationTest.kt
@@ -32,6 +32,7 @@ import dev.dnpm.etl.processor.output.RestDipMtbFileSender
 import dev.dnpm.etl.processor.output.RestNngmMtbFileSender
 import dev.dnpm.etl.processor.output.RoutedRestNngmMtbFileSender
 import dev.dnpm.etl.processor.pseudonym.AnonymizingGenerator
+import dev.dnpm.etl.processor.pseudonym.AnonymizingHmacGenerator
 import dev.dnpm.etl.processor.pseudonym.GpasPseudonymGenerator
 import dev.dnpm.etl.processor.pseudonym.GpasSoapPseudonymGenerator
 import dev.dnpm.etl.processor.security.TokenRepository
@@ -228,6 +229,17 @@ class AppConfigurationTest {
         }
 
         @Nested
+        @TestPropertySource(properties = ["app.pseudonymize.generator=buildin", "app.pseudonymize.hmac-key=Test"])
+        inner class AppConfigurationPseudonymizeGeneratorBuildinHmacTest(
+            private val context: ApplicationContext,
+        ) {
+            @Test
+            fun shouldUseConfiguredGenerator() {
+                assertThat(context.getBean<AnonymizingHmacGenerator>()).isNotNull
+            }
+        }
+
+        @Nested
         @TestPropertySource(
             properties =
                 ["app.pseudonymize.generator=gpas", "app.pseudonymize.gpas.uri=http://localhost/"],
diff --git a/src/main/kotlin/dev/dnpm/etl/processor/config/AppConfigProperties.kt b/src/main/kotlin/dev/dnpm/etl/processor/config/AppConfigProperties.kt
index fb93618..f0766a4 100644
--- a/src/main/kotlin/dev/dnpm/etl/processor/config/AppConfigProperties.kt
+++ b/src/main/kotlin/dev/dnpm/etl/processor/config/AppConfigProperties.kt
@@ -41,6 +41,7 @@ data class AppConfigProperties(
 data class PseudonymizeConfigProperties(
     var generator: PseudonymGenerator = PseudonymGenerator.BUILDIN,
     val prefix: String = "UNKNOWN",
+    val hmacKey: String? = null,
 ) {
     companion object {
         const val NAME = "app.pseudonymize"
diff --git a/src/main/kotlin/dev/dnpm/etl/processor/config/AppConfiguration.kt b/src/main/kotlin/dev/dnpm/etl/processor/config/AppConfiguration.kt
index d780642..54f4c6f 100644
--- a/src/main/kotlin/dev/dnpm/etl/processor/config/AppConfiguration.kt
+++ b/src/main/kotlin/dev/dnpm/etl/processor/config/AppConfiguration.kt
@@ -155,7 +155,11 @@ class AppConfiguration {
         matchIfMissing = true,
     )
     @Bean
-    fun buildinPseudonymGenerator(): Generator {
+    fun buildinPseudonymGenerator(pseudonymizeConfigProperties: PseudonymizeConfigProperties): Generator {
+        if (null != pseudonymizeConfigProperties.hmacKey) {
+            logger.info("Selected 'BUILDIN Pseudonym Generator' using HMAC")
+            return AnonymizingHmacGenerator(pseudonymizeConfigProperties)
+        }
         logger.info("Selected 'BUILDIN Pseudonym Generator'")
         return AnonymizingGenerator()
     }
diff --git a/src/main/kotlin/dev/dnpm/etl/processor/pseudonym/AnonymizingGenerator.kt b/src/main/kotlin/dev/dnpm/etl/processor/pseudonym/AnonymizingGenerator.kt
index b3c80e2..5e97568 100644
--- a/src/main/kotlin/dev/dnpm/etl/processor/pseudonym/AnonymizingGenerator.kt
+++ b/src/main/kotlin/dev/dnpm/etl/processor/pseudonym/AnonymizingGenerator.kt
@@ -25,8 +25,6 @@ import org.apache.commons.codec.digest.DigestUtils
 import java.security.SecureRandom
 
 class AnonymizingGenerator : Generator {
-    companion object
-
     fun getSecureRandom(): SecureRandom = SecureRandom()
 
     override fun generate(id: String): String = Base32().encodeAsString(DigestUtils.sha256(id)).substring(0..41).lowercase()
diff --git a/src/main/kotlin/dev/dnpm/etl/processor/pseudonym/AnonymizingHmacGenerator.kt b/src/main/kotlin/dev/dnpm/etl/processor/pseudonym/AnonymizingHmacGenerator.kt
new file mode 100644
index 0000000..646f6d3
--- /dev/null
+++ b/src/main/kotlin/dev/dnpm/etl/processor/pseudonym/AnonymizingHmacGenerator.kt
@@ -0,0 +1,52 @@
+/*
+ * This file is part of ETL-Processor
+ *
+ * Copyright (c) 2023       Comprehensive Cancer Center Mainfranken
+ * Copyright (c) 2023-2026  Paul-Christian Volkmer
+ *
+ * This program is free software: you can redistribute it and/or modify
+ * it under the terms of the GNU Affero General Public License as published
+ * by the Free Software Foundation, either version 3 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU Affero General Public License for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public License
+ * along with this program.  If not, see <https://www.gnu.org/licenses/>.
+ */
+
+package dev.dnpm.etl.processor.pseudonym
+
+import dev.dnpm.etl.processor.config.AppConfigProperties
+import dev.dnpm.etl.processor.config.PseudonymizeConfigProperties
+import org.apache.commons.codec.binary.Base32
+import org.apache.commons.codec.digest.DigestUtils
+import org.apache.commons.codec.digest.HmacAlgorithms
+import org.apache.commons.codec.digest.HmacUtils
+import java.security.SecureRandom
+
+/**
+ * Variant of AnonymizingGenerator that uses app.pseudonymize.prefix as HMAC-SHA256 key
+ */
+class AnonymizingHmacGenerator(
+    private val pseudonymizeConfigProperties: PseudonymizeConfigProperties,
+) : Generator {
+    fun getSecureRandom(): SecureRandom = SecureRandom()
+
+    override fun generate(id: String): String =
+        Base32()
+            .encodeAsString(HmacUtils(HmacAlgorithms.HMAC_SHA_256, pseudonymizeConfigProperties.hmacKey).hmac(id))
+            .substring(0..41)
+            .lowercase()
+
+    @OptIn(ExperimentalStdlibApi::class)
+    override fun generateGenomDeTan(id: String): String {
+        val bytes = ByteArray(64 / 2)
+        getSecureRandom().nextBytes(bytes)
+
+        return bytes.joinToString("") { "%02x".format(it) }
+    }
+}
diff --git a/src/test/kotlin/dev/dnpm/etl/processor/pseudonym/PseudonymizeServiceTest.kt b/src/test/kotlin/dev/dnpm/etl/processor/pseudonym/PseudonymizeServiceTest.kt
index 00487d0..3ac4df6 100644
--- a/src/test/kotlin/dev/dnpm/etl/processor/pseudonym/PseudonymizeServiceTest.kt
+++ b/src/test/kotlin/dev/dnpm/etl/processor/pseudonym/PseudonymizeServiceTest.kt
@@ -20,6 +20,7 @@
 
 package dev.dnpm.etl.processor.pseudonym
 
+import dev.dnpm.etl.processor.config.PseudonymGenerator
 import dev.dnpm.etl.processor.config.PseudonymizeConfigProperties
 import dev.pcvolkmer.mv64e.model.MtbEpisodeOfCare
 import dev.pcvolkmer.mv64e.model.Patient
@@ -31,72 +32,102 @@ import java.util.*
 import org.assertj.core.api.Assertions.assertThat
 import org.junit.jupiter.api.Test
 import org.junit.jupiter.api.extension.ExtendWith
+import org.junit.jupiter.params.ParameterizedTest
+import org.junit.jupiter.params.provider.Arguments
+import org.junit.jupiter.params.provider.MethodSource
 import org.mockito.ArgumentMatchers.anyString
 import org.mockito.Mock
 import org.mockito.junit.jupiter.MockitoExtension
 import org.mockito.kotlin.doAnswer
 import org.mockito.kotlin.whenever
+import java.util.stream.Stream
 
 @ExtendWith(MockitoExtension::class)
 class PseudonymizeServiceTest {
 
-  private val mtbFile =
-      PatientRecord.builder()
-          .patient(Patient.builder().id("123").build())
-          .episodesOfCare(
-              listOf(
-                  MtbEpisodeOfCare.builder()
-                      .id("1")
-                      .patient(Reference.builder().id("123").build())
-                      .period(
-                          PeriodDate.builder()
-                              .start(Date.from(Instant.parse("2021-01-01T00:00:00.00Z")))
-                              .build()
-                      )
-                      .build()
-              )
-          )
-          .build()
-
-  @Test
-  fun shouldNotUsePseudonymPrefixForGpas(@Mock generator: GpasPseudonymGenerator) {
-    doAnswer { it.arguments[0] }.whenever(generator).generate(anyString())
+    private val mtbFile =
+        PatientRecord.builder()
+            .patient(Patient.builder().id("123").build())
+            .episodesOfCare(
+                listOf(
+                    MtbEpisodeOfCare.builder()
+                        .id("1")
+                        .patient(Reference.builder().id("123").build())
+                        .period(
+                            PeriodDate.builder()
+                                .start(Date.from(Instant.parse("2021-01-01T00:00:00.00Z")))
+                                .build()
+                        )
+                        .build()
+                )
+            )
+            .build()
+
+    @Test
+    fun shouldNotUsePseudonymPrefixForGpas(@Mock generator: GpasPseudonymGenerator) {
+        doAnswer { it.arguments[0] }.whenever(generator).generate(anyString())
+
+        val pseudonymizeService = PseudonymizeService(generator, PseudonymizeConfigProperties())
+
+        mtbFile.pseudonymizeWith(pseudonymizeService)
+
+        assertThat(mtbFile.patient?.id).isEqualTo("123")
+    }
 
-    val pseudonymizeService = PseudonymizeService(generator, PseudonymizeConfigProperties())
+    @Test
+    fun sanitizeFileName() {
+        val result = GpasPseudonymGenerator.sanitizeValue("l://a\\bs;1*2?3>")
 
-    mtbFile.pseudonymizeWith(pseudonymizeService)
+        assertThat(result).isEqualTo("l___a_bs_1_2_3_")
+    }
 
-    assertThat(mtbFile.patient?.id).isEqualTo("123")
-  }
+    @Test
+    fun shouldUsePseudonymPrefixForBuiltin(@Mock generator: AnonymizingGenerator) {
+        doAnswer { it.arguments[0] }.whenever(generator).generate(anyString())
 
-  @Test
-  fun sanitizeFileName() {
-    val result = GpasPseudonymGenerator.sanitizeValue("l://a\\bs;1*2?3>")
+        val pseudonymizeService = PseudonymizeService(generator, PseudonymizeConfigProperties())
 
-    assertThat(result).isEqualTo("l___a_bs_1_2_3_")
-  }
+        mtbFile.pseudonymizeWith(pseudonymizeService)
 
-  @Test
-  fun shouldUsePseudonymPrefixForBuiltin(@Mock generator: AnonymizingGenerator) {
-    doAnswer { it.arguments[0] }.whenever(generator).generate(anyString())
+        assertThat(mtbFile.patient?.id).isEqualTo("UNKNOWN_123")
+    }
 
-    val pseudonymizeService = PseudonymizeService(generator, PseudonymizeConfigProperties())
+    @Test
+    fun shouldReturnDifferentValues() {
+        val ag = AnonymizingGenerator()
 
-    mtbFile.pseudonymizeWith(pseudonymizeService)
+        val tans = HashSet<String>()
 
-    assertThat(mtbFile.patient?.id).isEqualTo("UNKNOWN_123")
-  }
+        (1..1000).forEach { i ->
+            val tan = ag.generateGenomDeTan("12345")
+            assertThat(tan).hasSize(64)
+            assertThat(tans.add(tan)).`as`("never the same result!").isTrue
+        }
+    }
 
-  @Test
-  fun shouldReturnDifferentValues() {
-    val ag = AnonymizingGenerator()
+    @ParameterizedTest
+    @MethodSource("providePseudonymizeServiceTestProvider")
+    fun shouldGenerateExpectedPseudonym(generator: Generator, expected: String) {
+        val pseudonymizeService = PseudonymizeService(generator, PseudonymizeConfigProperties())
+        mtbFile.pseudonymizeWith(pseudonymizeService)
+        assertThat(mtbFile.patient?.id).isEqualTo(expected)
+    }
 
-    val tans = HashSet<String>()
+    companion object {
+
+        @JvmStatic
+        fun providePseudonymizeServiceTestProvider(): Stream<Arguments> {
+            return Stream.of(
+                Arguments.of(AnonymizingGenerator(), "UNKNOWN_uzs2iwjaiixz2ql6jbt67xcpxcqeuhz774p2a7uzr2"),
+                Arguments.of(
+                    AnonymizingHmacGenerator(
+                        PseudonymizeConfigProperties(
+                            hmacKey = "TEST"
+                        )
+                    ), "UNKNOWN_3u2nc3hzwbe2kylbmcrhoahgkisxl5jfbcwr3wonr3"
+                )
+            )
+        }
 
-    (1..1000).forEach { i ->
-      val tan = ag.generateGenomDeTan("12345")
-      assertThat(tan).hasSize(64)
-      assertThat(tans.add(tan)).`as`("never the same result!").isTrue
     }
-  }
 }