Implementing Stub Solver but not exposing (#598)

* stub core implementing

* validating structures

* address mapper tested

* testing and refactoring

* refactoring

* testing ipv4 validator

* testing

* new test

* refactoring

* clean code

* docs

* clean code

* release notes

* [Gradle Release Plugin] - new version commit:  '3.32.0-snapshot'.

* clearing todos

* clean code

* adjusting version

Author: mageddo

RELEASE-NOTES.md

@@ -1,3 +1,6 @@
+## 3.32.0
+* Implementing Stub Solver but not exposing. #545
+
 ## 3.31.1
 * Adjusting Canary Rate Threshold Circuit Breaker to mark all circuits as open at the start. #533
 

build.gradle

@@ -5,6 +5,7 @@ buildscript {
     mavenLocal()
     mavenCentral()
     gradlePluginPortal()
+    maven { url "https://oss.sonatype.org/service/local/repositories/releases/content" }
   }
 }
 
@@ -56,7 +57,7 @@ dependencies {
 
   implementation('jakarta.enterprise:jakarta.enterprise.cdi-api:2.0.2')
   implementation('jakarta.ws.rs:jakarta.ws.rs-api:2.1.6')
-  implementation('com.mageddo.commons:commons-lang:0.1.16')
+  implementation('com.mageddo.commons:commons-lang:0.1.21')
   implementation('org.apache.commons:commons-exec:1.3')
 
   implementation('ch.qos.logback:logback-classic:1.5.6')

gradle.properties

@@ -1 +1 @@
-version=3.31.1-snapshot
+version=3.32.0-snapshot

src/main/java/com/mageddo/dnsproxyserver/solver/stub/HostnameIpExtractor.java

@@ -0,0 +1,35 @@
+package com.mageddo.dnsproxyserver.solver.stub;
+
+import com.mageddo.dnsproxyserver.solver.stub.addressexpression.AddressExpressions;
+import com.mageddo.dnsproxyserver.solver.stub.addressexpression.ParseException;
+import com.mageddo.net.IP;
+import org.apache.commons.lang3.Validate;
+
+public class HostnameIpExtractor {
+
+  public static IP extract(String hostname, String domain) {
+
+    hostname = removeDomainFrom(hostname, domain);
+    Validate.notBlank(hostname, "Hostname is empty");
+
+    RuntimeException lastException = null;
+    for (int i = 0; i < hostname.length(); i++) {
+      try {
+        return AddressExpressions.toIp(hostname.substring(i));
+      } catch (ParseException e) {
+        lastException = e;
+      }
+    }
+
+    throw lastException;
+  }
+
+  static String removeDomainFrom(String hostname, String domain) {
+    final var idx = hostname.indexOf(domain);
+    if (idx < 0) {
+      return hostname;
+    }
+    return hostname.substring(0, idx - 1);
+  }
+
+}

src/main/java/com/mageddo/dnsproxyserver/solver/stub/SolverStub.java

@@ -0,0 +1,16 @@
+package com.mageddo.dnsproxyserver.solver.stub;
+
+import com.mageddo.dnsproxyserver.solver.Response;
+import com.mageddo.dnsproxyserver.solver.Solver;
+import org.xbill.DNS.Message;
+
+/**
+ * Extract the address from the hostname then answer.
+ * Inspired at nip.io and sslip.io, see #545.
+ */
+public class SolverStub implements Solver {
+  @Override
+  public Response handle(Message query) {
+    return null;
+  }
+}

src/main/java/com/mageddo/dnsproxyserver/solver/stub/addressexpression/AddressExpressions.java

@@ -0,0 +1,29 @@
+package com.mageddo.dnsproxyserver.solver.stub.addressexpression;
+
+import com.mageddo.net.IP;
+
+import java.util.List;
+
+public class AddressExpressions {
+
+  public static IP toIp(String addressExpression) {
+    RuntimeException lastException = null;
+    for (final var parser : buildParsers()) {
+      try {
+        return parser.parse(addressExpression);
+      } catch (ParseException e) {
+        lastException = e;
+      }
+    }
+    throw lastException;
+  }
+
+  static List<Parser> buildParsers() {
+    return List.of(
+      new Ipv6Parser(),
+      new Ipv4Parser(),
+      new HexadecimalParser()
+    );
+  }
+
+}

src/main/java/com/mageddo/dnsproxyserver/solver/stub/addressexpression/HexadecimalParser.java

@@ -0,0 +1,16 @@
+package com.mageddo.dnsproxyserver.solver.stub.addressexpression;
+
+import com.mageddo.net.IP;
+import org.apache.commons.codec.DecoderException;
+import org.apache.commons.codec.binary.Hex;
+
+public class HexadecimalParser implements Parser {
+  @Override
+  public IP parse(String addressExpression) {
+    try {
+      return IP.of(Hex.decodeHex(addressExpression));
+    } catch (DecoderException e) {
+      throw new ParseException("not a hexadecimal address: " + addressExpression, e);
+    }
+  }
+}

src/main/java/com/mageddo/dnsproxyserver/solver/stub/addressexpression/Ipv4Parser.java

@@ -0,0 +1,16 @@
+package com.mageddo.dnsproxyserver.solver.stub.addressexpression;
+
+import com.mageddo.dnsproxyserver.utils.Ips;
+import com.mageddo.net.IP;
+
+public class Ipv4Parser implements Parser {
+  @Override
+  public IP parse(String addressExpression) {
+    final var normalizedStr = addressExpression.replaceAll("-", ".");
+    if (Ips.isIpv4(normalizedStr)) {
+      return IP.of(normalizedStr);
+    }
+    throw new ParseException("invalid ipv4 address expression: " + addressExpression);
+  }
+
+}

src/main/java/com/mageddo/dnsproxyserver/solver/stub/addressexpression/Ipv6Parser.java

@@ -0,0 +1,27 @@
+package com.mageddo.dnsproxyserver.solver.stub.addressexpression;
+
+import com.mageddo.net.IP;
+import org.apache.commons.lang3.StringUtils;
+
+public class Ipv6Parser implements Parser {
+  @Override
+  public IP parse(String addressExpression) {
+    if (isIpv6(addressExpression)) {
+      try {
+        return IP.of(addressExpression.replaceAll("-", ":"));
+      } catch (RuntimeException e){
+        throw throwError(addressExpression);
+      }
+    }
+    throw throwError(addressExpression);
+  }
+
+  RuntimeException throwError(String addressExpression) {
+    throw new ParseException("Not ipv6 address: " + addressExpression);
+  }
+
+  static boolean isIpv6(String addressExpression) {
+    return (addressExpression.contains("--") || StringUtils.countMatches(addressExpression, "-") >= IP.IPV4_BYTES)
+           && !addressExpression.contains(".");
+  }
+}

src/main/java/com/mageddo/dnsproxyserver/solver/stub/addressexpression/ParseException.java

@@ -0,0 +1,12 @@
+package com.mageddo.dnsproxyserver.solver.stub.addressexpression;
+
+public class ParseException extends RuntimeException {
+
+  public ParseException(String message) {
+    super(message);
+  }
+
+  public ParseException(String message, Throwable cause) {
+    super(message, cause);
+  }
+}