solution: save remote client details into access log

src/main/kotlin/io/emeraldpay/dshackle/monitoring/accesslog/AccessHandler.kt

@@ -16,7 +16,6 @@
 package io.emeraldpay.dshackle.monitoring.accesslog
 
 import io.emeraldpay.api.proto.BlockchainOuterClass
-import io.emeraldpay.dshackle.Global
 import io.grpc.*
 import org.slf4j.LoggerFactory
 import org.springframework.beans.factory.annotation.Autowired
@@ -39,6 +38,7 @@ class AccessHandler(
         when (val method = call.methodDescriptor.bareMethodName) {
             "NativeCall" -> {
                 val builder = Events.NativeCallBuilder()
+                        .start(headers, call.attributes)
                 return OnNativeCall<ReqT, RespT>(
                         next.startCall(OnNativeCallResponse(call, builder), headers),
                         builder) { logs ->

src/main/kotlin/io/emeraldpay/dshackle/monitoring/accesslog/AccessLogWriter.kt

@@ -56,7 +56,7 @@ class AccessLogWriter(
     @PostConstruct
     fun start() {
         if (!config.enabled) {
-            log.info("Access Log is diabled")
+            log.info("Access Log is disabled")
             return
         }
         log.info("Writing Access Log to ${filename.absolutePath}")

src/main/kotlin/io/emeraldpay/dshackle/monitoring/accesslog/Events.kt

@@ -18,10 +18,15 @@ package io.emeraldpay.dshackle.monitoring.accesslog
 import com.fasterxml.jackson.annotation.JsonInclude
 import io.emeraldpay.api.proto.BlockchainOuterClass
 import io.emeraldpay.grpc.Chain
+import io.grpc.Attributes
+import io.grpc.Grpc
+import io.grpc.Metadata
+import org.apache.commons.lang3.StringUtils
 import org.slf4j.LoggerFactory
+import java.net.InetAddress
+import java.net.InetSocketAddress
 import java.time.Instant
 import java.util.*
-import kotlin.collections.ArrayList
 
 class Events {
 
@@ -65,11 +70,13 @@ class Events {
 
     data class StreamRequestDetails(
             val id: UUID,
-            val start: Instant
+            val start: Instant,
+            val remote: Remote
     )
 
     data class Remote(
             val ips: List<String>,
+            val ip: String,
             val userAgent: String
     )
 
@@ -88,15 +95,82 @@ class Events {
 
     class NativeCallBuilder() {
 
-        private val requestDetails = StreamRequestDetails(
+        companion object {
+            private val remoteIpKeys = listOf(
+                    Metadata.Key.of("x-real-ip", Metadata.ASCII_STRING_MARSHALLER),
+                    Metadata.Key.of("x-forwarded-for", Metadata.ASCII_STRING_MARSHALLER)
+            )
+            private val invalidCharacters = Regex("[\n\t]+")
+        }
+
+        private var requestDetails = StreamRequestDetails(
                 UUID.randomUUID(),
-                Instant.now()
+                Instant.now(),
+                Remote(emptyList(), "", "")
         )
 
         var chain: Int = Chain.UNSPECIFIED.id
         val items = ArrayList<NativeCallItemDetails>()
         val replies = HashMap<Int, NativeCallReplyDetails>()
 
+        private fun toInetAddress(ip: String): InetAddress? {
+            val isIp = Character.digit(ip[0], 16) != -1
+            if (!isIp) {
+                return null
+            }
+            return try {
+                InetAddress.getByName(ip)
+            } catch (t: Throwable) {
+                null
+            }
+        }
+
+        private fun findBestIp(ips: List<InetAddress>): InetAddress? {
+            // check if a real remote address is provided, otherwise use any local address
+            return ips.sortedWith(kotlin.Comparator { a, b ->
+                val aLocal = a.isLoopbackAddress || a.isSiteLocalAddress
+                val bLocal = b.isLoopbackAddress || b.isSiteLocalAddress
+                when {
+                    aLocal && bLocal -> 0
+                    aLocal -> 1
+                    else -> -1
+                }
+            }).firstOrNull()
+        }
+
+        private fun clean(s: String): String {
+            return StringUtils.truncate(s, 128)
+                    .replace(invalidCharacters, " ")
+                    .trim()
+        }
+
+        fun start(metadata: Metadata, attributes: Attributes): NativeCallBuilder {
+            val userAgent = metadata.get(Metadata.Key.of("user-agent", Metadata.ASCII_STRING_MARSHALLER))
+                    ?.let(this@NativeCallBuilder::clean)
+                    ?: ""
+            val ips = ArrayList<InetAddress>()
+            remoteIpKeys.forEach { key ->
+                metadata.get(key)?.let {
+                    it.trim().ifEmpty { null }
+                            ?.let(this@NativeCallBuilder::toInetAddress)
+                            ?.let(ips::add)
+                }
+            }
+            attributes.get(Grpc.TRANSPORT_ATTR_REMOTE_ADDR)?.let { addr ->
+                if (addr is InetSocketAddress) {
+                    ips.add(addr.address)
+                }
+            }
+            val ip = findBestIp(ips)?.hostAddress ?: ""
+            this.requestDetails = this.requestDetails
+                    .copy(remote = Remote(
+                            ips = ips.map { it.hostAddress },
+                            ip = ip,
+                            userAgent = userAgent
+                    ))
+            return this
+        }
+
         fun withChain(chain: Int): NativeCallBuilder {
             this.chain = chain
             return this

src/test/groovy/io/emeraldpay/dshackle/monitoring/accesslog/EventsNativeCallBuilderSpec.groovy

@@ -0,0 +1,207 @@
+/**
+ * Copyright (c) 2021 EmeraldPay, Inc
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *        http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+package io.emeraldpay.dshackle.monitoring.accesslog
+
+import io.emeraldpay.api.proto.BlockchainOuterClass
+import io.emeraldpay.grpc.Chain
+import io.grpc.Attributes
+import io.grpc.Grpc
+import io.grpc.Metadata
+import spock.lang.Specification
+
+class EventsNativeCallBuilderSpec extends Specification {
+
+    def "Parse headers from direct local access"() {
+        setup:
+        def metadata = new Metadata()
+        metadata.put(Metadata.Key.of("user-agent", Metadata.ASCII_STRING_MARSHALLER), "grpc-go/1.30.0")
+        def attributes = Attributes.newBuilder()
+                .set(Grpc.TRANSPORT_ATTR_REMOTE_ADDR, new InetSocketAddress(Inet4Address.getByName("127.0.0.1"), 2448))
+                .build()
+        when:
+        def act = new Events.NativeCallBuilder()
+                .start(metadata, attributes)
+                .withChain(Chain.ETHEREUM.id)
+                .onItem(BlockchainOuterClass.NativeCallItem.getDefaultInstance())
+                .build()
+        then:
+        act.size() == 1
+        with(act[0]) {
+            it.request != null
+            it.request.remote != null
+            with(it.request.remote) {
+                ips == ["127.0.0.1"]
+                userAgent == "grpc-go/1.30.0"
+                ip == "127.0.0.1"
+            }
+        }
+    }
+
+    def "Extracts real remote ip"() {
+        setup:
+        def metadata = new Metadata()
+        metadata.put(Metadata.Key.of("user-agent", Metadata.ASCII_STRING_MARSHALLER), "grpc-go/1.30.0")
+        metadata.put(Metadata.Key.of("x-real-ip", Metadata.ASCII_STRING_MARSHALLER), "30.56.100.15")
+        def attributes = Attributes.newBuilder()
+                .set(Grpc.TRANSPORT_ATTR_REMOTE_ADDR, new InetSocketAddress(Inet4Address.getByName("127.0.0.1"), 2448))
+                .build()
+        when:
+        def act = new Events.NativeCallBuilder()
+                .start(metadata, attributes)
+                .withChain(Chain.ETHEREUM.id)
+                .onItem(BlockchainOuterClass.NativeCallItem.getDefaultInstance())
+                .build()
+        then:
+        act.size() == 1
+        with(act[0].request.remote) {
+            ips == ["30.56.100.15", "127.0.0.1"]
+            ip == "30.56.100.15"
+        }
+    }
+
+    def "Ignores remote ip header if already connected from remote"() {
+        setup:
+        def metadata = new Metadata()
+        metadata.put(Metadata.Key.of("user-agent", Metadata.ASCII_STRING_MARSHALLER), "grpc-go/1.30.0")
+        metadata.put(Metadata.Key.of("x-real-ip", Metadata.ASCII_STRING_MARSHALLER), "192.168.1.1")
+        def attributes = Attributes.newBuilder()
+                .set(Grpc.TRANSPORT_ATTR_REMOTE_ADDR, new InetSocketAddress(Inet4Address.getByName("30.56.100.15"), 2448))
+                .build()
+        when:
+        def act = new Events.NativeCallBuilder()
+                .start(metadata, attributes)
+                .withChain(Chain.ETHEREUM.id)
+                .onItem(BlockchainOuterClass.NativeCallItem.getDefaultInstance())
+                .build()
+        then:
+        act.size() == 1
+        with(act[0].request.remote) {
+            ips == ["192.168.1.1", "30.56.100.15"]
+            userAgent == "grpc-go/1.30.0"
+            ip == "30.56.100.15"
+        }
+    }
+
+    def "Ignores invalid ip header"() {
+        setup:
+        def metadata = new Metadata()
+        metadata.put(Metadata.Key.of("user-agent", Metadata.ASCII_STRING_MARSHALLER), "grpc-go/1.30.0")
+        metadata.put(Metadata.Key.of("x-real-ip", Metadata.ASCII_STRING_MARSHALLER), "271.194.19.1")
+        def attributes = Attributes.newBuilder()
+                .set(Grpc.TRANSPORT_ATTR_REMOTE_ADDR, new InetSocketAddress(Inet4Address.getByName("30.56.100.15"), 2448))
+                .build()
+        when:
+        def act = new Events.NativeCallBuilder()
+                .start(metadata, attributes)
+                .withChain(Chain.ETHEREUM.id)
+                .onItem(BlockchainOuterClass.NativeCallItem.getDefaultInstance())
+                .build()
+        then:
+        act.size() == 1
+        with(act[0].request.remote) {
+            ips == ["30.56.100.15"]
+            userAgent == "grpc-go/1.30.0"
+            ip == "30.56.100.15"
+        }
+    }
+
+    def "Ignores host addr in ip header"() {
+        setup:
+        def metadata = new Metadata()
+        metadata.put(Metadata.Key.of("user-agent", Metadata.ASCII_STRING_MARSHALLER), "grpc-go/1.30.0")
+        metadata.put(Metadata.Key.of("x-real-ip", Metadata.ASCII_STRING_MARSHALLER), "google.com")
+        def attributes = Attributes.newBuilder()
+                .set(Grpc.TRANSPORT_ATTR_REMOTE_ADDR, new InetSocketAddress(Inet4Address.getByName("30.56.100.15"), 2448))
+                .build()
+        when:
+        def act = new Events.NativeCallBuilder()
+                .start(metadata, attributes)
+                .withChain(Chain.ETHEREUM.id)
+                .onItem(BlockchainOuterClass.NativeCallItem.getDefaultInstance())
+                .build()
+        then:
+        act.size() == 1
+        with(act[0].request.remote) {
+            ips == ["30.56.100.15"]
+            userAgent == "grpc-go/1.30.0"
+            ip == "30.56.100.15"
+        }
+    }
+
+    def "Extracts ipv6 addresses"() {
+        setup:
+        def metadata = new Metadata()
+        metadata.put(Metadata.Key.of("user-agent", Metadata.ASCII_STRING_MARSHALLER), "grpc-go/1.30.0")
+        metadata.put(Metadata.Key.of("x-real-ip", Metadata.ASCII_STRING_MARSHALLER), "2001:0db8:0000:0000:0000:ff00:0042:8329")
+        def attributes = Attributes.newBuilder()
+                .set(Grpc.TRANSPORT_ATTR_REMOTE_ADDR, new InetSocketAddress(Inet6Address.getByName("::1"), 2448))
+                .build()
+        when:
+        def act = new Events.NativeCallBuilder()
+                .start(metadata, attributes)
+                .withChain(Chain.ETHEREUM.id)
+                .onItem(BlockchainOuterClass.NativeCallItem.getDefaultInstance())
+                .build()
+        then:
+        act.size() == 1
+        with(act[0].request.remote) {
+            ips == ["2001:db8:0:0:0:ff00:42:8329", "0:0:0:0:0:0:0:1"]
+            ip == "2001:db8:0:0:0:ff00:42:8329"
+        }
+    }
+
+    def "Cleans up user agent"() {
+        setup:
+        def metadata = new Metadata()
+        metadata.put(Metadata.Key.of("user-agent", Metadata.ASCII_STRING_MARSHALLER), "grpc-go/1.30.0\nxss\n\r")
+        def attributes = Attributes.newBuilder()
+                .set(Grpc.TRANSPORT_ATTR_REMOTE_ADDR, new InetSocketAddress(Inet4Address.getByName("30.56.100.15"), 2448))
+                .build()
+        when:
+        def act = new Events.NativeCallBuilder()
+                .start(metadata, attributes)
+                .withChain(Chain.ETHEREUM.id)
+                .onItem(BlockchainOuterClass.NativeCallItem.getDefaultInstance())
+                .build()
+        then:
+        act.size() == 1
+        with(act[0].request.remote) {
+            userAgent == "grpc-go/1.30.0 xss"
+        }
+    }
+
+    def "Truncates up user agent to 128 characters max"() {
+        setup:
+        def metadata = new Metadata()
+        metadata.put(Metadata.Key.of("user-agent", Metadata.ASCII_STRING_MARSHALLER),
+                "0123456_1_0123456_2_0123456_3_0123456_4_0123456_5_0123456_6_0123456_7_0123456_8_0123456_9_0123456_0_0123456_1_0123456_2_0123456_3_0123456_4_0123456_5")
+        def attributes = Attributes.newBuilder()
+                .set(Grpc.TRANSPORT_ATTR_REMOTE_ADDR, new InetSocketAddress(Inet4Address.getByName("30.56.100.15"), 2448))
+                .build()
+        when:
+        def act = new Events.NativeCallBuilder()
+                .start(metadata, attributes)
+                .withChain(Chain.ETHEREUM.id)
+                .onItem(BlockchainOuterClass.NativeCallItem.getDefaultInstance())
+                .build()
+        then:
+        act.size() == 1
+        with(act[0].request.remote) {
+            userAgent.length() == 128
+            userAgent == "0123456_1_0123456_2_0123456_3_0123456_4_0123456_5_0123456_6_0123456_7_0123456_8_0123456_9_0123456_0_0123456_1_0123456_2_0123456_"
+        }
+    }
+}