Return 404 when the dns domain has any path different than /

Bumps [github.com/docker/docker](https://github.com/docker/docker) from 25.0.3+incompatible to 25.0.5+incompatible.
- [Release notes](https://github.com/docker/docker/releases)
- [Commits](https://github.com/docker/docker/compare/v25.0.3...v25.0.5)

---
updated-dependencies:
- dependency-name: github.com/docker/docker
  dependency-type: indirect
...

Signed-off-by: dependabot[bot] <support@github.com>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

.github/workflows/codeql-analysis.yml

@@ -29,16 +29,18 @@ jobs:
       contents: read
       security-events: write
 
-    strategy:
-      fail-fast: false
-
     steps:
     - name: Checkout repository
-      uses: actions/checkout@v3
+      uses: actions/checkout@v4
+
+    - name: install go
+      uses: actions/setup-go@v5
+      with:
+        go-version-file: go.mod
+        cache: true
 
-    # Initializes the CodeQL tools for scanning.
     - name: Initialize CodeQL
-      uses: github/codeql-action/init@v2
+      uses: github/codeql-action/init@v3
       with:
         languages: go
 
@@ -47,4 +49,4 @@ jobs:
        make build
 
     - name: Perform CodeQL Analysis
-      uses: github/codeql-action/analyze@v2
+      uses: github/codeql-action/analyze@v3

.github/workflows/main.yml

@@ -13,16 +13,16 @@ jobs:
     runs-on: ubuntu-latest
     strategy:
       matrix:
-        make: ["lint", "test"]
+        make: ["lint", "unit-test", "integration-test"]
     steps:
-      - uses: actions/checkout@v2.4.0
+      - uses: actions/checkout@v4
 
       - name: install go
-        uses: actions/setup-go@v2
+        uses: actions/setup-go@v5
         with:
-          go-version: "^1.19"
+          go-version-file: go.mod
 
-      - name: Lint
+      - name: ${{ matrix.make }}
         run: make ${{ matrix.make }}
 
   deploy:
@@ -33,9 +33,14 @@ jobs:
       matrix:
         goosarch: [linux-amd64]
     steps:
-      - uses: actions/checkout@v2.4.0
+      - uses: actions/checkout@v4
         with:
           fetch-depth: 0
+      - name: install go
+        uses: actions/setup-go@v5
+        with:
+          go-version-file: go.mod
+          cache: true
 
       - name: Set env
         run: echo "RELEASE_VERSION=${GITHUB_REF#refs/*/}" >> $GITHUB_ENV
@@ -56,7 +61,7 @@ jobs:
           sha256sum whatismyip-$RELEASE_VERSION-${{matrix.goosarch}}.tar.gz > whatismyip-$RELEASE_VERSION-${{matrix.goosarch}}.tar.gz.sha256
 
       - name: Release
-        uses: softprops/action-gh-release@v0.1.14
+        uses: softprops/action-gh-release@v2
         with:
           body_path: changelog.txt
           files: |

.golangci.yaml

@@ -0,0 +1,49 @@
+---
+run:
+  timeout: 10m
+issues:
+  max-same-issues: 0
+linters:
+  disable-all: true
+  enable:
+    - goimports
+    - ineffassign
+    - nakedret
+    - revive
+    - staticcheck
+    - stylecheck
+    - unconvert
+    - unparam
+    - unused
+linters-settings:
+  staticcheck:
+    checks:
+      - all
+  revive:
+    ignore-generated-header: true
+    severity: warning
+    confidence: 0.8
+    rules:
+      - name: blank-imports
+      - name: context-as-argument
+      - name: context-keys-type
+      - name: dot-imports
+      - name: error-return
+      - name: error-strings
+      - name: error-naming
+      - name: exported
+      - name: increment-decrement
+      - name: var-naming
+      - name: var-declaration
+      - name: package-comments
+      - name: range
+      - name: receiver-naming
+      - name: time-naming
+      - name: unexported-return
+      - name: indent-error-flow
+      - name: errorf
+      - name: empty-block
+      - name: superfluous-else
+      - name: unused-parameter
+      - name: unreachable-code
+      - name: redefines-builtin-id

Dockerfile

@@ -1,21 +1,28 @@
-FROM golang:1.19-alpine as builder
+FROM golang:1.22-alpine as builder
 
 ARG ARG_VERSION
 ENV VERSION $ARG_VERSION
 
 WORKDIR /app
-
+COPY go.mod .
+COPY go.sum .
+RUN --mount=type=cache,target=/go/pkg/mod/ go mod download -x
 COPY . .
 
-RUN apk add make git && make build VERSION=$VERSION
+FROM builder AS build-dev-app
+# hadolint ignore=DL3018
+RUN --mount=type=cache,target=/go/pkg/mod/ apk --no-cache add make && make build
 
-# Build final image
+FROM builder AS build-prod-app
-FROM scratch
+# hadolint ignore=DL3018
-
+RUN --mount=type=cache,target=/go/pkg/mod/ apk --no-cache add make upx \
-WORKDIR /app
+    && make build \
-
+    && upx --best --lzma whatismyip
-COPY --from=builder /app/whatismyip /usr/bin/
-
-EXPOSE 8080
 
+FROM scratch AS dev
+COPY --from=build-dev-app /app/whatismyip /usr/bin/
+ENTRYPOINT ["whatismyip"]
+
+FROM scratch AS prod
+COPY --from=build-prod-app /app/whatismyip /usr/bin/
 ENTRYPOINT ["whatismyip"]

LICENSE

@@ -176,7 +176,7 @@
 
    END OF TERMS AND CONDITIONS
 
-   Copyright 2021 Daniel Carrillo
+   Copyright 2024 Daniel Carrillo
 
    Licensed under the Apache License, Version 2.0 (the "License");
    you may not use this file except in compliance with the License.

Makefile

@@ -5,44 +5,40 @@ DOCKER_URL ?= dcarrillo/whatismyip
 .PHONY: test
 test: unit-test integration-test
 
-.PHONY: unit-test
 unit-test:
-	go test -race -short -cover ./...
+	go test -count=1 -race -short -cover ./...
 
-.PHONY: integration-test
 integration-test:
-	go test ./integration-tests -v
+	go test -count=1 -v ./integration-tests
 
-.PHONY: install-tools
 install-tools:
 	@command golangci-lint > /dev/null 2>&1; if [ $$? -ne 0 ]; then \
-		curl -sSfL https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh | sh -s -- -b $(GOPATH)/bin v1.45.2; \
+		curl -sSfL https://raw.githubusercontent.com/golangci/golangci-lint/master/install.sh | sh -s -- -b $(GOPATH)/bin; \
+	fi
+
+	@command $(GOPATH)/revive > /dev/null 2>&1; if [ $$? -ne 0 ]; then \
+		go get -u github.com/mgechev/revive; \
 	fi
 
 	@command $(GOPATH)/shadow > /dev/null 2>&1; if [ $$? -ne 0 ]; then \
-		go install golang.org/x/tools/go/analysis/passes/shadow/cmd/shadow@v0.1.10; \
+		go install golang.org/x/tools/go/analysis/passes/shadow/cmd/shadow@latest; \
 	fi
 
-	@command $(GOPATH)/golines > /dev/null 2>&1; if [ $$? -ne 0 ]; then \
-		go install github.com/segmentio/golines@latest; \
-	fi
-.PHONY: lint
 lint: install-tools
 	gofmt -l . && test -z $$(gofmt -l .)
-	golines -l . && test -z $$(golines -l .)
 	golangci-lint run
 	shadow ./...
 
-.PHONY: build
 build:
 	CGO_ENABLED=0 go build -ldflags="-s -w -X 'github.com/dcarrillo/whatismyip/internal/core.Version=${VERSION}'" -o whatismyip ./cmd
 
-.PHONY: docker-build
+docker-build-dev:
-docker-build:
+	docker build --target=dev --build-arg=ARG_VERSION="${VERSION}" --tag ${DOCKER_URL}:${VERSION} .
-	docker build --build-arg=ARG_VERSION="${VERSION}" --tag ${DOCKER_URL}:${VERSION} .
 
-.PHONY: docker-push
+docker-build-prod:
-docker-push: docker-build
+	docker build --target=prod --build-arg=ARG_VERSION="${VERSION}" --tag ${DOCKER_URL}:${VERSION} .
+
+docker-push: docker-build-prod
 ifneq (,$(findstring devel-,$(VERSION)))
 	@echo "VERSION is set to ${VERSION}, I can't push devel builds"
 	exit 1
@@ -52,8 +48,7 @@ else
 	docker push ${DOCKER_URL}:latest
 endif
 
-.PHONY: docker-run
+docker-run: docker-build-dev
-docker-run: docker-build
 	docker run --tty --interactive --rm \
 	-v ${PWD}/test/GeoIP2-City-Test.mmdb:/tmp/GeoIP2-City-Test.mmdb:ro \
 	-v ${PWD}/test/GeoLite2-ASN-Test.mmdb:/tmp/GeoLite2-ASN-Test.mmdb:ro -p 8080:8080 \

README.md

@@ -9,20 +9,26 @@
 - [What is my IP address](#what-is-my-ip-address)
   - [Features](#features)
   - [Endpoints](#endpoints)
+  - [DNS discovery](#dns-discovery)
   - [Build](#build)
   - [Usage](#usage)
   - [Examples](#examples)
     - [Run a default TCP server](#run-a-default-tcp-server)
-    - [Run a TLS (HTTP/2) server only](#run-a-tls-http2-server-only)
+    - [Run a TLS (HTTP/2) and enable What is my DNS](#run-a-tls-http2-and-enable-what-is-my-dns)
+    - [Run an HTTP/3 server](#run-an-http3-server)
     - [Run a default TCP server with a custom template and trust a pair of custom headers set by an upstream proxy](#run-a-default-tcp-server-with-a-custom-template-and-trust-a-pair-of-custom-headers-set-by-an-upstream-proxy)
   - [Download](#download)
   - [Docker](#docker)
     - [Run a container locally using test databases](#run-a-container-locally-using-test-databases)
     - [From Docker Hub](#from-docker-hub)
 
-Just another "what is my IP address" service, including geolocation and headers information, written in go with high performance in mind, it uses [gin](https://github.com/gin-gonic/gin) which uses [httprouter](https://github.com/julienschmidt/httprouter) a lightweight high performance HTTP multiplexer.
+> [!NOTE]  
+> Since version 2.3.0, the application includes an optional client [DNS discovery](#dns-discovery)
 
-Take a look at [ifconfig.es](https://ifconfig.es) a live site using `whatismyip`
+Just another "what is my IP address" service, including geolocation, TCP open port checking, and headers information. Written in go with high performance in mind,
+it uses [gin](https://github.com/gin-gonic/gin) which uses [httprouter](https://github.com/julienschmidt/httprouter) a lightweight high performance HTTP multiplexer.
+
+Take a look at [ifconfig.es](https://ifconfig.es) a live site using `whatismyip` and the `DNS discovery` enabled.
 
 Get your public IP easily from the command line:
 
@@ -34,14 +40,24 @@ curl -6 ifconfig.es
 ::1
 ```
 
+Get the IP of your DNS provider:
+
+```bash
+curl -L dns.ifconfig.es
+2a04:e4c0:47::67 (Spain / OPENDNS)
+```
+
 ## Features
 
 - TLS and HTTP/2.
+- Experimental HTTP/3 support. HTTP/3 requires a TLS server running (`-tls-bind`), as HTTP/3 starts as a TLS connection that then gets upgraded to UDP. The UDP port is the same as the one used for the TLS server.
+- Beta DNS discovery: A best-effort approach to discovering the DNS server that is resolving the client's requests.
 - Can run behind a proxy by trusting a custom header (usually `X-Real-IP`) to figure out the source IP address. It also supports a custom header to resolve the client port, if the proxy can only add a header for the IP (for example a fixed header from CDNs) the client port is shown as unknown.
 - IPv4 and IPv6.
 - Geolocation info including ASN. This feature is possible thanks to [maxmind](https://dev.maxmind.com/geoip/geolite2-free-geolocation-data?lang=en) GeoLite2 databases. In order to use these databases, a license key is needed. Please visit Maxmind site for further instructions and get a free license.
+- Checking TCP open ports.
 - High performance.
-- Self-contained server what can reload GeoLite2 databases and/or SSL certificates without stop/start. The `hup` signal is honored.
+- Self-contained server that can reload GeoLite2 databases and/or SSL certificates without stop/start. The `hup` signal is honored.
 - HTML templates for the landing page.
 - Text plain and JSON output.
 
@@ -64,10 +80,42 @@ curl -6 ifconfig.es
 - https://ifconfig.es/all
 - https://ifconfig.es/headers
   - https://ifconfig.es/<header_name>
+- https://ifconfig.es/scan/tcp/<port_number>
+- https://dns.ifconfig.es
+
+## DNS discovery
+
+The DNS discovery works by forcing the client to make a request to `<uuid>.dns.ifconfig.es` this DNS request is handled by a microdns server
+included in the `whatismyip` binary. In order to run the discovery server, a configuration file in the following form has to be created:
+
+```yaml
+---
+domain: dns.example.com
+redirect_port: ":8000"
+resource_records:
+  - "1800 IN SOA xns.example.com. hostmaster.example.com. 1 10000 2400 604800 1800"
+  - "3600 IN NS xns.example.com."
+ipv4:
+  - "127.0.0.2"
+ipv6:
+  - "aaa:aaa:aaa:aaaa::1"
+```
+
+The DNS authority for example.com has delegated the subdomain zone `dns.example.com` to the server running the `whatismyip` service.
+
+The client can request the URL `dns.example.com` by following the redirection `curl -L dns.example.com`.
+
+To avoid the redirection, you can provide a valid URL, for example, for the real [ifconfig.es](https://ifconfig.es):
+
+```bash
+curl $(uuidgen).dns.ifconfig.es
+
+curl $(cat /proc/sys/kernel/random/uuid).dns.ifconfig.es
+```
 
 ## Build
 
-Golang >= 1.17 is required. Previous versions may work.
+Golang >= 1.22 is required.
 
 `make build`
 
@@ -77,12 +125,16 @@ Golang >= 1.17 is required. Previous versions may work.
 Usage of whatismyip:
   -bind string
         Listening address (see https://pkg.go.dev/net?#Listen) (default ":8080")
+  -enable-http3
+        Enable HTTP/3 protocol. HTTP/3 requires --tls-bind set, as HTTP/3 starts as a TLS connection that then gets upgraded to UDP. The UDP port is the same as the one used for the TLS server.
   -enable-secure-headers
         Add sane security-related headers to every response
   -geoip2-asn string
         Path to GeoIP2 ASN database
   -geoip2-city string
         Path to GeoIP2 city database
+  -resolver string
+        Path to the resolver configuration. It actually enables the resolver for DNS client discovery.
   -template string
         Path to template file
   -tls-bind string
@@ -107,11 +159,19 @@ Usage of whatismyip:
 ./whatismyip -geoip2-city ./test/GeoIP2-City-Test.mmdb -geoip2-asn ./test/GeoLite2-ASN-Test.mmdb
 ```
 
-### Run a TLS (HTTP/2) server only
+### Run a TLS (HTTP/2) and enable What is my DNS
 
 ```bash
 ./whatismyip -geoip2-city ./test/GeoIP2-City-Test.mmdb -geoip2-asn ./test/GeoLite2-ASN-Test.mmdb \
-             -bind "" -tls-bind :8081 -tls-crt ./test/server.pem -tls-key ./test/server.key
+             -bind "" -tls-bind :8081 -tls-crt ./test/server.pem -tls-key ./test/server.key \
+             -resolver ./test/resolver.yml
+```
+
+### Run an HTTP/3 server
+
+```bash
+./whatismyip -geoip2-city ./test/GeoIP2-City-Test.mmdb -geoip2-asn ./test/GeoLite2-ASN-Test.mmdb \
+             -bind "" -tls-bind :8081 -tls-crt ./test/server.pem -tls-key ./test/server.key -enable-http3
 ```
 
 ### Run a default TCP server with a custom template and trust a pair of custom headers set by an upstream proxy
@@ -123,11 +183,11 @@ Usage of whatismyip:
 
 ## Download
 
-Download latest version from https://github.com/dcarrillo/whatismyip/releases
+Download the latest version from [github](https://github.com/dcarrillo/whatismyip/releases)
 
 ## Docker
 
-An ultra-light (~10MB) image is available at [docker hub](https://hub.docker.com/r/dcarrillo/whatismyip).
+An ultra-light (~4MB) image is available on [docker hub](https://hub.docker.com/r/dcarrillo/whatismyip). Since version `2.1.2`, the binary is compressed using [upx](https://github.com/upx/upx).
 
 ### Run a container locally using test databases
 

cmd/whatismyip.go

@@ -2,142 +2,59 @@ package main
 
 import (
 	"context"
-	"errors"
 	"flag"
 	"fmt"
-	"log"
 	"net/http"
 	"os"
-	"os/signal"
+	"slices"
-	"syscall"
+	"time"
 
 	"github.com/dcarrillo/whatismyip/internal/httputils"
 	"github.com/dcarrillo/whatismyip/internal/setting"
+	"github.com/dcarrillo/whatismyip/resolver"
+	"github.com/dcarrillo/whatismyip/server"
 	"github.com/gin-contrib/secure"
+	"github.com/patrickmn/go-cache"
 
-	"github.com/dcarrillo/whatismyip/models"
 	"github.com/dcarrillo/whatismyip/router"
-
 	"github.com/gin-gonic/gin"
 )
 
-var (
-	tcpServer *http.Server
-	tlsServer *http.Server
-	engine    *gin.Engine
-)
-
 func main() {
 	o, err := setting.Setup(os.Args[1:])
 	if err == flag.ErrHelp || err == setting.ErrVersion {
 		fmt.Print(o)
 		os.Exit(0)
 	} else if err != nil {
-		fmt.Print(err)
+		fmt.Println(err)
 		os.Exit(1)
 	}
 
-	models.Setup(setting.App.GeodbPath.City, setting.App.GeodbPath.ASN)
+	servers := []server.Server{}
-	setupEngine()
+	engine := setupEngine()
+
+	if setting.App.Resolver.Domain != "" {
+		store := cache.New(1*time.Minute, 10*time.Minute)
+		dnsEngine := resolver.Setup(store)
+		nameServer := server.NewDNSServer(context.Background(), dnsEngine.Handler())
+		servers = append(servers, nameServer)
+		engine.Use(router.GetDNSDiscoveryHandler(store, setting.App.Resolver.Domain, setting.App.Resolver.RedirectPort))
+	}
+
 	router.SetupTemplate(engine)
 	router.Setup(engine)
+	servers = slices.Concat(servers, setupHTTPServers(context.Background(), engine.Handler()))
 
-	if setting.App.BindAddress != "" {
+	whatismyip := server.Setup(servers)
-		runTCPServer()
+	whatismyip.Run()
 }
 
-	if setting.App.TLSAddress != "" {
+func setupEngine() *gin.Engine {
-		runTLSServer()
-	}
-
-	runHandler()
-}
-
-func runHandler() {
-	signalChan := make(chan os.Signal, 3)
-	signal.Notify(signalChan, syscall.SIGHUP, syscall.SIGINT, syscall.SIGTERM)
-	ctx := context.Background()
-	var s os.Signal
-
-	for {
-		s = <-signalChan
-
-		if s == syscall.SIGHUP {
-			models.CloseDBs()
-			models.Setup(setting.App.GeodbPath.City, setting.App.GeodbPath.ASN)
-			router.SetupTemplate(engine)
-
-			if setting.App.BindAddress != "" {
-				if err := tcpServer.Shutdown(ctx); err != nil {
-					log.Printf("TCP server forced to shutdown: %s", err)
-				}
-				runTCPServer()
-			}
-			if setting.App.TLSAddress != "" {
-				if err := tlsServer.Shutdown(ctx); err != nil {
-					log.Printf("TLS server forced to shutdown: %s", err)
-				}
-				runTLSServer()
-			}
-		} else {
-			log.Printf("Shutting down...")
-			if setting.App.BindAddress != "" {
-				if err := tcpServer.Shutdown(ctx); err != nil {
-					log.Printf("TCP server forced to shutdown: %s", err)
-				}
-			}
-			if setting.App.TLSAddress != "" {
-				if err := tlsServer.Shutdown(ctx); err != nil {
-					log.Printf("TLS server forced to shutdown: %s", err)
-				}
-			}
-			models.CloseDBs()
-			break
-		}
-	}
-}
-
-func runTCPServer() {
-	tcpServer = &http.Server{
-		Addr:         setting.App.BindAddress,
-		Handler:      engine,
-		ReadTimeout:  setting.App.Server.ReadTimeout,
-		WriteTimeout: setting.App.Server.WriteTimeout,
-	}
-
-	go func() {
-		log.Printf("Starting TCP server listening on %s", setting.App.BindAddress)
-		if err := tcpServer.ListenAndServe(); err != nil && !errors.Is(err, http.ErrServerClosed) {
-			log.Fatal(err)
-		}
-		log.Printf("Stopping TCP server...")
-	}()
-}
-
-func runTLSServer() {
-	tlsServer = &http.Server{
-		Addr:         setting.App.TLSAddress,
-		Handler:      engine,
-		ReadTimeout:  setting.App.Server.ReadTimeout,
-		WriteTimeout: setting.App.Server.WriteTimeout,
-	}
-
-	go func() {
-		log.Printf("Starting TLS server listening on %s", setting.App.TLSAddress)
-		if err := tlsServer.ListenAndServeTLS(setting.App.TLSCrtPath, setting.App.TLSKeyPath); err != nil &&
-			!errors.Is(err, http.ErrServerClosed) {
-			log.Fatal(err)
-		}
-		log.Printf("Stopping TLS server...")
-	}()
-}
-
-func setupEngine() {
 	gin.DisableConsoleColor()
 	if os.Getenv(gin.EnvGinMode) == "" {
 		gin.SetMode(gin.ReleaseMode)
 	}
-	engine = gin.New()
+	engine := gin.New()
 	engine.Use(gin.LoggerWithFormatter(httputils.GetLogFormatter))
 	engine.Use(gin.Recovery())
 	if setting.App.EnableSecureHeaders {
@@ -149,4 +66,26 @@ func setupEngine() {
 	}
 	_ = engine.SetTrustedProxies(nil)
 	engine.TrustedPlatform = setting.App.TrustedHeader
+
+	return engine
+}
+
+func setupHTTPServers(ctx context.Context, handler http.Handler) []server.Server {
+	var servers []server.Server
+
+	if setting.App.BindAddress != "" {
+		tcpServer := server.NewTCPServer(ctx, &handler)
+		servers = append(servers, tcpServer)
+	}
+
+	if setting.App.TLSAddress != "" {
+		tlsServer := server.NewTLSServer(ctx, &handler)
+		servers = append(servers, tlsServer)
+		if setting.App.EnableHTTP3 {
+			quicServer := server.NewQuicServer(ctx, tlsServer)
+			servers = append(servers, quicServer)
+		}
+	}
+
+	return servers
 }

go.mod

@@ -1,62 +1,220 @@
 module github.com/dcarrillo/whatismyip
 
-go 1.19
+go 1.22
 
 require (
-	github.com/gin-contrib/secure v0.0.1
+	github.com/gin-contrib/secure v1.0.0
-	github.com/gin-gonic/gin v1.8.2
+	github.com/gin-gonic/gin v1.10.0
-	github.com/oschwald/maxminddb-golang v1.10.0
+	github.com/google/uuid v1.6.0
-	github.com/stretchr/testify v1.8.1
+	github.com/miekg/dns v1.1.58
-	github.com/testcontainers/testcontainers-go v0.13.0
+	github.com/oschwald/maxminddb-golang v1.12.0
+	github.com/patrickmn/go-cache v2.1.0+incompatible
+	github.com/quic-go/quic-go v0.42.0
+	github.com/stretchr/testify v1.9.0
+	github.com/testcontainers/testcontainers-go/modules/compose v0.29.1
+	gopkg.in/yaml.v3 v3.0.1
 )
 
 require (
+	dario.cat/mergo v1.0.0 // indirect
+	github.com/AdaLogics/go-fuzz-headers v0.0.0-20230811130428-ced1acdcaa24 // indirect
+	github.com/AlecAivazis/survey/v2 v2.3.7 // indirect
 	github.com/Azure/go-ansiterm v0.0.0-20210617225240-d185dfc1b5a1 // indirect
-	github.com/Microsoft/go-winio v0.5.2 // indirect
+	github.com/BurntSushi/toml v1.3.2 // indirect
-	github.com/Microsoft/hcsshim v0.9.5 // indirect
+	github.com/Masterminds/semver/v3 v3.2.1 // indirect
-	github.com/cenkalti/backoff/v4 v4.1.3 // indirect
+	github.com/Microsoft/go-winio v0.6.1 // indirect
-	github.com/containerd/cgroups v1.0.4 // indirect
+	github.com/Microsoft/hcsshim v0.11.4 // indirect
-	github.com/containerd/containerd v1.6.12 // indirect
+	github.com/aws/aws-sdk-go-v2 v1.17.6 // indirect
+	github.com/aws/aws-sdk-go-v2/config v1.18.16 // indirect
+	github.com/aws/aws-sdk-go-v2/credentials v1.13.16 // indirect
+	github.com/aws/aws-sdk-go-v2/feature/ec2/imds v1.12.24 // indirect
+	github.com/aws/aws-sdk-go-v2/internal/configsources v1.1.30 // indirect
+	github.com/aws/aws-sdk-go-v2/internal/endpoints/v2 v2.4.24 // indirect
+	github.com/aws/aws-sdk-go-v2/internal/ini v1.3.31 // indirect
+	github.com/aws/aws-sdk-go-v2/service/internal/presigned-url v1.9.24 // indirect
+	github.com/aws/aws-sdk-go-v2/service/sso v1.12.5 // indirect
+	github.com/aws/aws-sdk-go-v2/service/ssooidc v1.14.5 // indirect
+	github.com/aws/aws-sdk-go-v2/service/sts v1.18.6 // indirect
+	github.com/aws/smithy-go v1.13.5 // indirect
+	github.com/beorn7/perks v1.0.1 // indirect
+	github.com/buger/goterm v1.0.4 // indirect
+	github.com/bytedance/sonic v1.11.6 // indirect
+	github.com/bytedance/sonic/loader v0.1.1 // indirect
+	github.com/cenkalti/backoff/v4 v4.2.1 // indirect
+	github.com/cespare/xxhash/v2 v2.2.0 // indirect
+	github.com/cloudwego/base64x v0.1.4 // indirect
+	github.com/cloudwego/iasm v0.2.0 // indirect
+	github.com/compose-spec/compose-go/v2 v2.0.0-rc.2 // indirect
+	github.com/containerd/console v1.0.3 // indirect
+	github.com/containerd/containerd v1.7.12 // indirect
+	github.com/containerd/continuity v0.4.2 // indirect
+	github.com/containerd/log v0.1.0 // indirect
+	github.com/containerd/typeurl/v2 v2.1.1 // indirect
+	github.com/cpuguy83/dockercfg v0.3.1 // indirect
 	github.com/davecgh/go-spew v1.1.1 // indirect
-	github.com/docker/distribution v2.8.1+incompatible // indirect
+	github.com/distribution/reference v0.5.0 // indirect
-	github.com/docker/docker v20.10.17+incompatible // indirect
+	github.com/docker/buildx v0.12.0-rc2.0.20231219140829-617f538cb315 // indirect
-	github.com/docker/go-connections v0.4.0 // indirect
+	github.com/docker/cli v25.0.1+incompatible // indirect
-	github.com/docker/go-units v0.4.0 // indirect
+	github.com/docker/compose/v2 v2.24.3 // indirect
+	github.com/docker/distribution v2.8.3+incompatible // indirect
+	github.com/docker/docker v25.0.5+incompatible // indirect
+	github.com/docker/docker-credential-helpers v0.8.0 // indirect
+	github.com/docker/go v1.5.1-1.0.20160303222718-d30aec9fd63c // indirect
+	github.com/docker/go-connections v0.5.0 // indirect
+	github.com/docker/go-metrics v0.0.1 // indirect
+	github.com/docker/go-units v0.5.0 // indirect
+	github.com/emicklei/go-restful/v3 v3.10.1 // indirect
+	github.com/felixge/httpsnoop v1.0.4 // indirect
+	github.com/fsnotify/fsevents v0.1.1 // indirect
+	github.com/fvbommel/sortorder v1.0.2 // indirect
+	github.com/gabriel-vasile/mimetype v1.4.3 // indirect
 	github.com/gin-contrib/sse v0.1.0 // indirect
-	github.com/go-playground/locales v0.14.0 // indirect
+	github.com/go-logr/logr v1.2.4 // indirect
-	github.com/go-playground/universal-translator v0.18.0 // indirect
+	github.com/go-logr/stdr v1.2.2 // indirect
-	github.com/go-playground/validator/v10 v10.11.1 // indirect
+	github.com/go-ole/go-ole v1.2.6 // indirect
-	github.com/goccy/go-json v0.10.0 // indirect
+	github.com/go-openapi/jsonpointer v0.19.5 // indirect
+	github.com/go-openapi/jsonreference v0.20.0 // indirect
+	github.com/go-openapi/swag v0.19.14 // indirect
+	github.com/go-playground/locales v0.14.1 // indirect
+	github.com/go-playground/universal-translator v0.18.1 // indirect
+	github.com/go-playground/validator/v10 v10.20.0 // indirect
+	github.com/go-task/slim-sprig v0.0.0-20230315185526-52ccab3ef572 // indirect
+	github.com/goccy/go-json v0.10.2 // indirect
+	github.com/gofrs/flock v0.8.1 // indirect
+	github.com/gogo/googleapis v1.4.1 // indirect
 	github.com/gogo/protobuf v1.3.2 // indirect
-	github.com/golang/groupcache v0.0.0-20210331224755-41bb18bfe9da // indirect
+	github.com/golang/protobuf v1.5.3 // indirect
-	github.com/golang/protobuf v1.5.2 // indirect
+	github.com/google/gnostic v0.5.7-v3refs // indirect
-	github.com/google/uuid v1.3.0 // indirect
+	github.com/google/go-cmp v0.6.0 // indirect
+	github.com/google/gofuzz v1.2.0 // indirect
+	github.com/google/pprof v0.0.0-20210407192527-94a9f03dee38 // indirect
+	github.com/google/shlex v0.0.0-20191202100458-e7afc7fbc510 // indirect
+	github.com/gorilla/mux v1.8.1 // indirect
+	github.com/grpc-ecosystem/go-grpc-middleware v1.3.0 // indirect
+	github.com/grpc-ecosystem/grpc-gateway/v2 v2.16.0 // indirect
+	github.com/hashicorp/errwrap v1.1.0 // indirect
+	github.com/hashicorp/go-cleanhttp v0.5.2 // indirect
+	github.com/hashicorp/go-multierror v1.1.1 // indirect
+	github.com/hashicorp/go-version v1.6.0 // indirect
+	github.com/imdario/mergo v0.3.16 // indirect
+	github.com/in-toto/in-toto-golang v0.5.0 // indirect
+	github.com/inconshreveable/mousetrap v1.1.0 // indirect
+	github.com/jonboulle/clockwork v0.4.0 // indirect
+	github.com/josharian/intern v1.0.0 // indirect
 	github.com/json-iterator/go v1.1.12 // indirect
-	github.com/leodido/go-urn v1.2.1 // indirect
+	github.com/kballard/go-shellquote v0.0.0-20180428030007-95032a82bc51 // indirect
-	github.com/magiconair/properties v1.8.6 // indirect
+	github.com/klauspost/compress v1.17.4 // indirect
-	github.com/mattn/go-isatty v0.0.16 // indirect
+	github.com/klauspost/cpuid/v2 v2.2.7 // indirect
-	github.com/moby/sys/mount v0.3.3 // indirect
+	github.com/leodido/go-urn v1.4.0 // indirect
-	github.com/moby/sys/mountinfo v0.6.2 // indirect
+	github.com/lufia/plan9stats v0.0.0-20211012122336-39d0f177ccd0 // indirect
-	github.com/moby/term v0.0.0-20220808134915-39b0c02b01ae // indirect
+	github.com/magiconair/properties v1.8.7 // indirect
+	github.com/mailru/easyjson v0.7.6 // indirect
+	github.com/mattn/go-colorable v0.1.13 // indirect
+	github.com/mattn/go-isatty v0.0.20 // indirect
+	github.com/mattn/go-runewidth v0.0.15 // indirect
+	github.com/mattn/go-shellwords v1.0.12 // indirect
+	github.com/matttproud/golang_protobuf_extensions v1.0.4 // indirect
+	github.com/mgutz/ansi v0.0.0-20170206155736-9520e82c474b // indirect
+	github.com/miekg/pkcs11 v1.1.1 // indirect
+	github.com/mitchellh/copystructure v1.2.0 // indirect
+	github.com/mitchellh/mapstructure v1.5.0 // indirect
+	github.com/mitchellh/reflectwalk v1.0.2 // indirect
+	github.com/moby/buildkit v0.13.0-beta1.0.20231219135447-957cb50df991 // indirect
+	github.com/moby/locker v1.0.1 // indirect
+	github.com/moby/patternmatcher v0.6.0 // indirect
+	github.com/moby/spdystream v0.2.0 // indirect
+	github.com/moby/sys/mountinfo v0.7.1 // indirect
+	github.com/moby/sys/sequential v0.5.0 // indirect
+	github.com/moby/sys/signal v0.7.0 // indirect
+	github.com/moby/sys/symlink v0.2.0 // indirect
+	github.com/moby/sys/user v0.1.0 // indirect
+	github.com/moby/term v0.5.0 // indirect
 	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
 	github.com/modern-go/reflect2 v1.0.2 // indirect
 	github.com/morikuni/aec v1.0.0 // indirect
+	github.com/munnerz/goautoneg v0.0.0-20191010083416-a7dc8b61c822 // indirect
+	github.com/onsi/ginkgo/v2 v2.9.5 // indirect
 	github.com/opencontainers/go-digest v1.0.0 // indirect
-	github.com/opencontainers/image-spec v1.0.3-0.20211202183452-c5a74bcca799 // indirect
+	github.com/opencontainers/image-spec v1.1.0 // indirect
-	github.com/opencontainers/runc v1.1.3 // indirect
+	github.com/pelletier/go-toml v1.9.5 // indirect
-	github.com/pelletier/go-toml/v2 v2.0.6 // indirect
+	github.com/pelletier/go-toml/v2 v2.2.2 // indirect
 	github.com/pkg/errors v0.9.1 // indirect
 	github.com/pmezard/go-difflib v1.0.0 // indirect
-	github.com/sirupsen/logrus v1.9.0 // indirect
+	github.com/power-devops/perfstat v0.0.0-20210106213030-5aafc221ea8c // indirect
-	github.com/ugorji/go/codec v1.2.7 // indirect
+	github.com/prometheus/client_golang v1.16.0 // indirect
-	go.opencensus.io v0.23.0 // indirect
+	github.com/prometheus/client_model v0.4.0 // indirect
-	golang.org/x/crypto v0.4.0 // indirect
+	github.com/prometheus/common v0.42.0 // indirect
-	golang.org/x/net v0.4.0 // indirect
+	github.com/prometheus/procfs v0.10.1 // indirect
-	golang.org/x/sys v0.3.0 // indirect
+	github.com/quic-go/qpack v0.4.0 // indirect
-	golang.org/x/text v0.5.0 // indirect
+	github.com/rivo/uniseg v0.4.7 // indirect
-	google.golang.org/genproto v0.0.0-20220810155839-1856144b1d9c // indirect
+	github.com/secure-systems-lab/go-securesystemslib v0.4.0 // indirect
-	google.golang.org/grpc v1.48.0 // indirect
+	github.com/serialx/hashring v0.0.0-20190422032157-8b2912629002 // indirect
-	google.golang.org/protobuf v1.28.1 // indirect
+	github.com/shibumi/go-pathspec v1.3.0 // indirect
+	github.com/shirou/gopsutil/v3 v3.23.12 // indirect
+	github.com/shoenig/go-m1cpu v0.1.6 // indirect
+	github.com/sirupsen/logrus v1.9.3 // indirect
+	github.com/spf13/cobra v1.8.0 // indirect
+	github.com/spf13/pflag v1.0.5 // indirect
+	github.com/testcontainers/testcontainers-go v0.29.1 // indirect
+	github.com/theupdateframework/notary v0.7.0 // indirect
+	github.com/tilt-dev/fsnotify v1.4.8-0.20220602155310-fff9c274a375 // indirect
+	github.com/tklauser/go-sysconf v0.3.12 // indirect
+	github.com/tklauser/numcpus v0.6.1 // indirect
+	github.com/tonistiigi/fsutil v0.0.0-20230825212630-f09800878302 // indirect
+	github.com/tonistiigi/units v0.0.0-20180711220420-6950e57a87ea // indirect
+	github.com/tonistiigi/vt100 v0.0.0-20230623042737-f9a4f7ef6531 // indirect
+	github.com/twitchyliquid64/golang-asm v0.15.1 // indirect
+	github.com/ugorji/go/codec v1.2.12 // indirect
+	github.com/xeipuuv/gojsonpointer v0.0.0-20190905194746-02993c407bfb // indirect
+	github.com/xeipuuv/gojsonreference v0.0.0-20180127040603-bd5ef7bd5415 // indirect
+	github.com/xeipuuv/gojsonschema v1.2.0 // indirect
+	github.com/yusufpapurcu/wmi v1.2.3 // indirect
+	go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc v0.45.0 // indirect
+	go.opentelemetry.io/contrib/instrumentation/net/http/httptrace/otelhttptrace v0.45.0 // indirect
+	go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.45.0 // indirect
+	go.opentelemetry.io/otel v1.19.0 // indirect
+	go.opentelemetry.io/otel/exporters/otlp/otlpmetric v0.42.0 // indirect
+	go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetricgrpc v0.42.0 // indirect
+	go.opentelemetry.io/otel/exporters/otlp/otlpmetric/otlpmetrichttp v0.42.0 // indirect
+	go.opentelemetry.io/otel/exporters/otlp/otlptrace v1.19.0 // indirect
+	go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracegrpc v1.19.0 // indirect
+	go.opentelemetry.io/otel/exporters/otlp/otlptrace/otlptracehttp v1.19.0 // indirect
+	go.opentelemetry.io/otel/exporters/prometheus v0.42.0 // indirect
+	go.opentelemetry.io/otel/metric v1.19.0 // indirect
+	go.opentelemetry.io/otel/sdk v1.19.0 // indirect
+	go.opentelemetry.io/otel/sdk/metric v1.19.0 // indirect
+	go.opentelemetry.io/otel/trace v1.19.0 // indirect
+	go.opentelemetry.io/proto/otlp v1.0.0 // indirect
+	go.uber.org/mock v0.4.0 // indirect
+	golang.org/x/arch v0.8.0 // indirect
+	golang.org/x/crypto v0.23.0 // indirect
+	golang.org/x/exp v0.0.0-20230713183714-613f0c0eb8a1 // indirect
+	golang.org/x/mod v0.17.0 // indirect
+	golang.org/x/net v0.25.0 // indirect
+	golang.org/x/oauth2 v0.15.0 // indirect
+	golang.org/x/sync v0.7.0 // indirect
+	golang.org/x/sys v0.20.0 // indirect
+	golang.org/x/term v0.20.0 // indirect
+	golang.org/x/text v0.15.0 // indirect
+	golang.org/x/time v0.5.0 // indirect
+	golang.org/x/tools v0.20.0 // indirect
+	google.golang.org/appengine v1.6.7 // indirect
+	google.golang.org/genproto v0.0.0-20231106174013-bbf56f31fb17 // indirect
+	google.golang.org/genproto/googleapis/api v0.0.0-20231106174013-bbf56f31fb17 // indirect
+	google.golang.org/genproto/googleapis/rpc v0.0.0-20231120223509-83a465c0220f // indirect
+	google.golang.org/grpc v1.59.0 // indirect
+	google.golang.org/protobuf v1.34.1 // indirect
+	gopkg.in/inf.v0 v0.9.1 // indirect
 	gopkg.in/yaml.v2 v2.4.0 // indirect
-	gopkg.in/yaml.v3 v3.0.1 // indirect
+	k8s.io/api v0.26.7 // indirect
+	k8s.io/apimachinery v0.26.7 // indirect
+	k8s.io/apiserver v0.26.7 // indirect
+	k8s.io/client-go v0.26.7 // indirect
+	k8s.io/klog/v2 v2.90.1 // indirect
+	k8s.io/kube-openapi v0.0.0-20221012153701-172d655c2280 // indirect
+	k8s.io/utils v0.0.0-20230220204549-a5ecb0141aa5 // indirect
+	sigs.k8s.io/json v0.0.0-20220713155537-f223a00ba0e2 // indirect
+	sigs.k8s.io/structured-merge-diff/v4 v4.2.3 // indirect
+	sigs.k8s.io/yaml v1.3.0 // indirect
+	tags.cncf.io/container-device-interface v0.6.2 // indirect
 )

integration-tests/integration_test.go

@@ -4,55 +4,75 @@ import (
 	"context"
 	"crypto/tls"
 	"encoding/json"
+	"fmt"
 	"io"
-	"log"
+	"net"
 	"net/http"
-	"path/filepath"
+	"strings"
-	"runtime"
 	"testing"
 
+	validator "github.com/dcarrillo/whatismyip/internal/validator/uuid"
 	"github.com/dcarrillo/whatismyip/router"
+	"github.com/quic-go/quic-go/http3"
 	"github.com/stretchr/testify/assert"
-	"github.com/testcontainers/testcontainers-go"
+	"github.com/stretchr/testify/require"
-	"github.com/testcontainers/testcontainers-go/wait"
+	tc "github.com/testcontainers/testcontainers-go/modules/compose"
 )
 
-func buildContainer() testcontainers.ContainerRequest {
+func customDialContext() func(ctx context.Context, network, addr string) (net.Conn, error) {
-	_, filename, _, _ := runtime.Caller(0)
+	return func(ctx context.Context, network, addr string) (net.Conn, error) {
-	dir := filepath.Dir(filename)
+		dialer := &net.Dialer{
-
+			Resolver: &net.Resolver{
-	req := testcontainers.ContainerRequest{
+				PreferGo: true,
-		FromDockerfile: testcontainers.FromDockerfile{
+				Dial: func(ctx context.Context, _, _ string) (net.Conn, error) {
-			Context:    "../",
+					d := net.Dialer{}
-			Dockerfile: "Dockerfile",
+					return d.DialContext(ctx, "udp", "127.0.0.1:53531")
 				},
-		Cmd: []string{
-			"-geoip2-city", "/tmp/GeoIP2-City-Test.mmdb",
-			"-geoip2-asn", "/tmp/GeoLite2-ASN-Test.mmdb",
-			"-bind", ":8000",
-			"-tls-bind", ":8001",
-			"-tls-crt", "/tmp/server.pem",
-			"-tls-key", "/tmp/server.key",
-			"-trusted-header", "X-Real-IP",
-			"-enable-secure-headers",
 			},
-		ExposedPorts: []string{"8000:8000", "8001:8001"},
-		WaitingFor:   wait.ForLog("Starting TLS server listening on :8001"),
-		Mounts: testcontainers.Mounts(
-			testcontainers.BindMount(
-				filepath.Join(dir, "/../test/GeoIP2-City-Test.mmdb"),
-				"/tmp/GeoIP2-City-Test.mmdb",
-			),
-			testcontainers.BindMount(
-				filepath.Join(dir, "/../test/GeoLite2-ASN-Test.mmdb"),
-				"/tmp/GeoLite2-ASN-Test.mmdb",
-			),
-			testcontainers.BindMount(filepath.Join(dir, "/../test/server.pem"), "/tmp/server.pem"),
-			testcontainers.BindMount(filepath.Join(dir, "/../test/server.key"), "/tmp/server.key"),
-		),
 		}
 
-	return req
+		return dialer.DialContext(ctx, network, addr)
+	}
+}
+
+func testWhatIsMyDNS(t *testing.T) {
+	t.Run("RequestDNSDiscovery", func(t *testing.T) {
+		http.DefaultTransport.(*http.Transport).DialContext = customDialContext()
+		req, err := http.NewRequest("GET", "http://localhost:8000", nil)
+		assert.NoError(t, err)
+		req.Host = "dns.example.com"
+		client := &http.Client{
+			CheckRedirect: func(_ *http.Request, _ []*http.Request) error {
+				return http.ErrUseLastResponse
+			},
+		}
+
+		resp, err := client.Do(req)
+		assert.NoError(t, err)
+		assert.Equal(t, http.StatusFound, resp.StatusCode)
+		u, err := resp.Location()
+		assert.NoError(t, err)
+		assert.True(t, validator.IsValid(strings.Split(u.Hostname(), ".")[0]))
+
+		for _, accept := range []string{"application/json", "*/*", "text/html"} {
+			req, err = http.NewRequest("GET", u.String(), nil)
+			req.Host = u.Hostname()
+			req.Header.Set("Accept", accept)
+			assert.NoError(t, err)
+			resp, err = client.Do(req)
+			assert.NoError(t, err)
+			assert.Equal(t, http.StatusOK, resp.StatusCode)
+			body, err := io.ReadAll(resp.Body)
+			assert.NoError(t, err)
+
+			if accept == "application/json" {
+				assert.NoError(t, json.Unmarshal(body, &router.DNSJSONResponse{}))
+			} else {
+				ip := strings.Split(string(body), " ")[0]
+				assert.True(t, net.ParseIP(ip) != nil)
+			}
+		}
+	})
 }
 
 func TestContainerIntegration(t *testing.T) {
@@ -60,37 +80,126 @@ func TestContainerIntegration(t *testing.T) {
 		t.Skip("Skiping integration tests")
 	}
 
-	ctx := context.Background()
+	compose, err := tc.NewDockerComposeWith(tc.WithStackFiles("../test/docker-compose.yml"), tc.StackIdentifier("whatismyip"))
-	container, err := testcontainers.GenericContainer(ctx, testcontainers.GenericContainerRequest{
+	require.NoError(t, err, "NewDockerComposeAPIWith()")
-		ContainerRequest: buildContainer(),
+
-		Started:          true,
+	t.Cleanup(func() {
+		require.NoError(t, compose.Down(context.Background(), tc.RemoveOrphans(true), tc.RemoveImagesLocal), "compose.Down()")
 	})
-	if err != nil {
+	ctx, cancel := context.WithCancel(context.Background())
-		log.Fatal(err)
+	t.Cleanup(cancel)
-	}
+	require.NoError(t, compose.Up(ctx, tc.Wait(true)), "compose.Up()")
-	defer func() {
-		err := container.Terminate(ctx)
-		if err != nil {
-			log.Fatal(err)
-		}
-	}()
 
 	http.DefaultTransport.(*http.Transport).TLSClientConfig = &tls.Config{InsecureSkipVerify: true}
-	for _, url := range []string{"http://localhost:8000", "https://localhost:8001"} {
+	tests := []struct {
-		client := &http.Client{}
+		name string
-		req, _ := http.NewRequest("GET", url, nil)
+		url  string
-		req.Header.Set("Accept", "application/json")
+		quic bool
-		resp, _ := client.Do(req)
+	}{
-		assert.Equal(t, 200, resp.StatusCode)
+		{
-
+			name: "RequestOverHTTP",
-		body, err := io.ReadAll(resp.Body)
+			url:  "http://localhost:8000",
-		if err != nil {
+			quic: false,
-			log.Fatal(err)
+		},
+		{
+			name: "RequestOverHTTPs",
+			url:  "https://localhost:8001",
+			quic: false,
+		},
+		{
+			name: "RequestOverUDPWithQuic",
+			url:  "https://localhost:8001",
+			quic: true,
+		},
 	}
 
+	testsPortScan := []struct {
+		name string
+		port int
+		want bool
+	}{
+		{
+			name: "RequestOpenPortScan",
+			port: 8000,
+			want: true,
+		},
+		{
+			name: "RequestClosedPortScan",
+			port: 65533,
+			want: false,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			req, err := http.NewRequest("GET", tt.url, nil)
+			assert.NoError(t, err)
+			req.Header.Set("Accept", "application/json")
+
+			var resp *http.Response
+			var body []byte
+			if tt.quic {
+				resp, body, err = doQuicRequest(req)
+			} else {
+				client := &http.Client{}
+				resp, _ = client.Do(req)
+				body, err = io.ReadAll(resp.Body)
+				if strings.Contains(tt.url, "https://") {
+					assert.Equal(t, `h3=":8001"; ma=2592000`, resp.Header.Get("Alt-Svc"))
+				}
+			}
+			assert.NoError(t, err)
+			assert.Equal(t, 200, resp.StatusCode)
+
 			assert.NoError(t, json.Unmarshal(body, &router.JSONResponse{}))
 			assert.Equal(t, "DENY", resp.Header.Get("X-Frame-Options"))
 			assert.Equal(t, "nosniff", resp.Header.Get("X-Content-Type-Options"))
 			assert.Equal(t, "1; mode=block", resp.Header.Get("X-Xss-Protection"))
+		})
 	}
+
+	for _, tt := range testsPortScan {
+		t.Run(tt.name, func(t *testing.T) {
+			req, err := http.NewRequest("GET", fmt.Sprintf("http://localhost:8000/scan/tcp/%d", tt.port), nil)
+			assert.NoError(t, err)
+			req.Header.Set("Accept", "application/json")
+			req.Header.Set("X-Real-IP", "127.0.0.1")
+
+			client := &http.Client{}
+			resp, err := client.Do(req)
+			assert.NoError(t, err)
+			assert.Equal(t, 200, resp.StatusCode)
+
+			body, err := io.ReadAll(resp.Body)
+			assert.NoError(t, err)
+			j := router.JSONScanResponse{}
+			assert.NoError(t, json.Unmarshal(body, &j))
+			assert.Equal(t, tt.want, j.Reachable)
+		})
+	}
+
+	testWhatIsMyDNS(t)
+}
+
+func doQuicRequest(req *http.Request) (*http.Response, []byte, error) {
+	roundTripper := &http3.RoundTripper{
+		TLSClientConfig: &tls.Config{
+			InsecureSkipVerify: true,
+		},
+	}
+	defer roundTripper.Close()
+
+	client := &http.Client{
+		Transport: roundTripper,
+	}
+
+	resp, err := client.Do(req)
+	if err != nil {
+		return nil, nil, err
+	}
+
+	defer resp.Body.Close()
+	body, _ := io.ReadAll(resp.Body)
+
+	return resp, body, nil
 }

internal/httputils/http.go

@@ -63,7 +63,7 @@ func GetLogFormatter(param gin.LogFormatterParams) string {
 	)
 }
 
-func normalizeLog(log interface{}) interface{} {
+func normalizeLog(log any) any {
 	switch v := log.(type) {
 	case string:
 		if v == "" {

internal/setting/app.go

@@ -9,6 +9,7 @@ import (
 	"time"
 
 	"github.com/dcarrillo/whatismyip/internal/core"
+	"gopkg.in/yaml.v3"
 )
 
 type geodbPath struct {
@@ -19,6 +20,15 @@ type serverSettings struct {
 	ReadTimeout  time.Duration
 	WriteTimeout time.Duration
 }
+
+type resolver struct {
+	Domain          string   `yaml:"domain"`
+	ResourceRecords []string `yaml:"resource_records"`
+	RedirectPort    string   `yaml:"redirect_port,omitempty"`
+	Ipv4            []string `yaml:"ipv4,omitempty"`
+	Ipv6            []string `yaml:"ipv6,omitempty"`
+}
+
 type settings struct {
 	GeodbPath           geodbPath
 	TemplatePath        string
@@ -29,16 +39,16 @@ type settings struct {
 	TrustedHeader       string
 	TrustedPortHeader   string
 	EnableSecureHeaders bool
+	EnableHTTP3         bool
 	Server              serverSettings
+	Resolver            resolver
 	version             bool
 }
 
 const defaultAddress = ":8080"
 
-// ErrVersion is the custom error triggered when -version flag is passed
 var ErrVersion = errors.New("setting: version requested")
 
-// App is the var with the parsed settings
 var App = settings{
 	// hard-coded for the time being
 	Server: serverSettings{
@@ -47,15 +57,20 @@ var App = settings{
 	},
 }
 
-// Setup initializes the App object parsing the flags
 func Setup(args []string) (output string, err error) {
 	flags := flag.NewFlagSet("whatismyip", flag.ContinueOnError)
 	var buf bytes.Buffer
+	var resolverConf string
 	flags.SetOutput(&buf)
 
 	flags.StringVar(&App.GeodbPath.City, "geoip2-city", "", "Path to GeoIP2 city database")
 	flags.StringVar(&App.GeodbPath.ASN, "geoip2-asn", "", "Path to GeoIP2 ASN database")
-	flags.StringVar(&App.TemplatePath, "template", "", "Path to template file")
+	flags.StringVar(&App.TemplatePath, "template", "", "Path to the template file")
+	flags.StringVar(
+		&resolverConf,
+		"resolver",
+		"",
+		"Path to the resolver configuration. It actually enables the resolver for DNS client discovery.")
 	flags.StringVar(
 		&App.BindAddress,
 		"bind",
@@ -89,6 +104,12 @@ func Setup(args []string) (output string, err error) {
 		false,
 		"Add sane security-related headers to every response",
 	)
+	flags.BoolVar(
+		&App.EnableHTTP3,
+		"enable-http3",
+		false,
+		"Enable HTTP/3 protocol. HTTP/3 requires --tls-bind set, as HTTP/3 starts as a TLS connection that then gets upgraded to UDP. The UDP port is the same as the one used for the TLS server.",
+	)
 
 	err = flags.Parse(args)
 	if err != nil {
@@ -100,26 +121,46 @@ func Setup(args []string) (output string, err error) {
 	}
 
 	if App.TrustedPortHeader != "" && App.TrustedHeader == "" {
-		return "", fmt.Errorf("truster-header is mandatory when truster-port-header is set\n")
+		return "", fmt.Errorf("truster-header is mandatory when truster-port-header is set")
 	}
 
 	if App.GeodbPath.City == "" || App.GeodbPath.ASN == "" {
-		return "", fmt.Errorf("geoip2-city and geoip2-asn parameters are mandatory\n")
+		return "", fmt.Errorf("geoip2-city and geoip2-asn parameters are mandatory")
 	}
 
 	if (App.TLSAddress != "") && (App.TLSCrtPath == "" || App.TLSKeyPath == "") {
-		return "", fmt.Errorf("In order to use TLS -tls-crt and -tls-key flags are mandatory\n")
+		return "", fmt.Errorf("in order to use TLS, the -tls-crt and -tls-key flags are mandatory")
+	}
+
+	if App.EnableHTTP3 && App.TLSAddress == "" {
+		return "", fmt.Errorf("in order to use HTTP3, the -tls-bind is mandatory")
 	}
 
 	if App.TemplatePath != "" {
 		info, err := os.Stat(App.TemplatePath)
 		if os.IsNotExist(err) {
-			return "", fmt.Errorf("%s no such file or directory\n", App.TemplatePath)
+			return "", fmt.Errorf("%s no such file or directory", App.TemplatePath)
 		}
 		if info.IsDir() {
-			return "", fmt.Errorf("%s must be a file\n", App.TemplatePath)
+			return "", fmt.Errorf("%s must be a file", App.TemplatePath)
+		}
+	}
+
+	if resolverConf != "" {
+		var err error
+		App.Resolver, err = readYAML(resolverConf)
+		if err != nil {
+			return "", fmt.Errorf("error reading resolver configuration %s", err)
 		}
 	}
 
 	return buf.String(), nil
 }
+
+func readYAML(path string) (resolver resolver, err error) {
+	yamlFile, err := os.ReadFile(path)
+	if err != nil {
+		return resolver, err
+	}
+	return resolver, yaml.Unmarshal(yamlFile, &resolver)
+}

internal/setting/app_test.go

@@ -41,6 +41,11 @@ func TestParseMandatoryFlags(t *testing.T) {
 				"-tls-key", "/key-path",
 			},
 		},
+		{
+			[]string{
+				"-geoip2-city", "/city-path", "-geoip2-asn", "/asn-path", "-enable-http3",
+			},
+		},
 		{
 			[]string{
 				"-geoip2-city", "/city-path", "-geoip2-asn", "/asn-path", "-bind", ":8000",

internal/validator/uuid/uuid.go

@@ -0,0 +1,10 @@
+package uuid
+
+import (
+	"github.com/google/uuid"
+)
+
+func IsValid(u string) bool {
+	_, err := uuid.Parse(u)
+	return err == nil
+}

internal/validator/uuid/uuid_test.go

@@ -0,0 +1,37 @@
+package uuid
+
+import (
+	"testing"
+
+	"github.com/stretchr/testify/assert"
+)
+
+func TestIsValid(t *testing.T) {
+	tests := []struct {
+		name string
+		u    string
+		want bool
+	}{
+		{
+			name: "Valid UUID",
+			u:    "3b241101-e2bb-4255-8caf-4136c566a964",
+			want: true,
+		},
+		{
+			name: "Invalid UUID",
+			u:    "invalid-uuid",
+			want: false,
+		},
+		{
+			name: "Empty string",
+			u:    "",
+			want: false,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			assert.True(t, IsValid(tt.u) == tt.want)
+		})
+	}
+}

models/geo.go

@@ -68,18 +68,10 @@ func CloseDBs() {
 
 // LookUp an IP and get city data
 func (record *GeoRecord) LookUp(ip net.IP) error {
-	if err := db.city.Lookup(ip, record); err != nil {
+	return db.city.Lookup(ip, record)
-		return err
-	}
-
-	return nil
 }
 
 // LookUp an IP and get ASN data
 func (record *ASNRecord) LookUp(ip net.IP) error {
-	if err := db.asn.Lookup(ip, record); err != nil {
+	return db.asn.Lookup(ip, record)
-		return err
-	}
-
-	return nil
 }

resolver/setup.go

@@ -0,0 +1,165 @@
+package resolver
+
+import (
+	"log"
+	"net"
+	"strings"
+
+	"github.com/dcarrillo/whatismyip/internal/setting"
+	"github.com/dcarrillo/whatismyip/internal/validator/uuid"
+	"github.com/miekg/dns"
+	"github.com/patrickmn/go-cache"
+)
+
+type Resolver struct {
+	handler *dns.ServeMux
+	store   *cache.Cache
+	domain  string
+	rr      []string
+	ipv4    []net.IP
+	ipv6    []net.IP
+}
+
+func ensureDotSuffix(s string) string {
+	if !strings.HasSuffix(s, ".") {
+		return s + "."
+	}
+	return s
+}
+
+func Setup(store *cache.Cache) *Resolver {
+	var ipv4, ipv6 []net.IP
+	for _, ip := range setting.App.Resolver.Ipv4 {
+		ipv4 = append(ipv4, net.ParseIP(ip))
+	}
+	for _, ip := range setting.App.Resolver.Ipv6 {
+		ipv6 = append(ipv6, net.ParseIP(ip))
+	}
+
+	resolver := &Resolver{
+		handler: dns.NewServeMux(),
+		store:   store,
+		domain:  ensureDotSuffix(setting.App.Resolver.Domain),
+		rr:      setting.App.Resolver.ResourceRecords,
+		ipv4:    ipv4,
+		ipv6:    ipv6,
+	}
+	resolver.handler.HandleFunc(resolver.domain, resolver.resolve)
+	resolver.handler.HandleFunc(".", resolver.blackHole)
+
+	return resolver
+}
+
+func (rsv *Resolver) Handler() *dns.ServeMux {
+	return rsv.handler
+}
+
+func (rsv *Resolver) blackHole(w dns.ResponseWriter, r *dns.Msg) {
+	msg := startReply(r)
+	msg.SetRcode(r, dns.RcodeRefused)
+	w.WriteMsg(msg)
+	logger(w, r.Question[0], msg.Rcode)
+}
+
+func (rsv *Resolver) resolve(w dns.ResponseWriter, r *dns.Msg) {
+	msg := startReply(r)
+	q := r.Question[0]
+	ip, _, _ := net.SplitHostPort(w.RemoteAddr().String())
+
+	for _, res := range rsv.rr {
+		t := strings.Split(res, " ")[2]
+		if q.Qtype == dns.StringToType[t] {
+			brr, err := buildRR(rsv.domain + " " + res)
+			if err != nil {
+				msg.SetRcode(r, dns.RcodeServerFailure)
+				logger(w, q, msg.Rcode, err.Error())
+			} else {
+				msg.Answer = append(msg.Answer, brr)
+				logger(w, q, msg.Rcode)
+			}
+			w.WriteMsg(msg)
+			return
+		}
+	}
+
+	lowerName := strings.ToLower(q.Name) // lowercase because of dns-0x20
+	subDomain := strings.Split(lowerName, ".")[0]
+	switch {
+	case uuid.IsValid(subDomain):
+		msg.SetRcode(r, rsv.getIP(q, msg))
+		rsv.store.Add(subDomain, ip, cache.DefaultExpiration)
+	case lowerName == rsv.domain:
+		msg.SetRcode(r, rsv.getIP(q, msg))
+	default:
+		msg.SetRcode(r, dns.RcodeRefused)
+	}
+
+	w.WriteMsg(msg)
+	logger(w, q, msg.Rcode)
+}
+
+func (rsv *Resolver) getIP(question dns.Question, msg *dns.Msg) int {
+	if question.Qtype == dns.TypeA && len(rsv.ipv4) > 0 {
+		for _, ip := range rsv.ipv4 {
+			msg.Answer = append(msg.Answer, &dns.A{
+				Hdr: setHdr(question),
+				A:   ip,
+			})
+		}
+		return dns.RcodeSuccess
+	}
+
+	if question.Qtype == dns.TypeAAAA && len(rsv.ipv6) > 0 {
+		for _, ip := range rsv.ipv6 {
+			msg.Answer = append(msg.Answer, &dns.AAAA{
+				Hdr:  setHdr(question),
+				AAAA: ip,
+			})
+		}
+		return dns.RcodeSuccess
+	}
+
+	return dns.RcodeRefused
+}
+
+func buildRR(rrs string) (dns.RR, error) {
+	rr, err := dns.NewRR(rrs)
+	if err != nil {
+		return nil, err
+	}
+
+	return rr, nil
+}
+
+func setHdr(q dns.Question) dns.RR_Header {
+	return dns.RR_Header{
+		Name:   q.Name,
+		Rrtype: q.Qtype,
+		Class:  dns.ClassINET,
+		Ttl:    60,
+	}
+}
+
+func startReply(r *dns.Msg) *dns.Msg {
+	msg := new(dns.Msg)
+	msg.SetReply(r)
+	msg.Authoritative = true
+
+	return msg
+}
+
+func logger(w dns.ResponseWriter, q dns.Question, code int, err ...string) {
+	emsg := ""
+	if len(err) > 0 {
+		emsg = " - " + strings.Join(err, " ")
+	}
+	ip, _, _ := net.SplitHostPort(w.RemoteAddr().String())
+	log.Printf(
+		"DNS %s - %s - %s - %s%s",
+		ip,
+		dns.TypeToString[q.Qtype],
+		q.Name,
+		dns.RcodeToString[code],
+		emsg,
+	)
+}

router/dns.go

@@ -0,0 +1,85 @@
+package router
+
+import (
+	"fmt"
+	"net"
+	"net/http"
+	"strings"
+
+	validator "github.com/dcarrillo/whatismyip/internal/validator/uuid"
+	"github.com/dcarrillo/whatismyip/service"
+	"github.com/gin-gonic/gin"
+	"github.com/google/uuid"
+	"github.com/patrickmn/go-cache"
+)
+
+type DNSJSONResponse struct {
+	DNS dnsData `json:"dns"`
+}
+type dnsData struct {
+	IP              string `json:"ip"`
+	Country         string `json:"country"`
+	AsnOrganization string `json:"provider"`
+}
+
+// TODO
+// Implement a proper vhost manager instead of using a middleware
+func GetDNSDiscoveryHandler(store *cache.Cache, domain string, redirectPort string) gin.HandlerFunc {
+	return func(ctx *gin.Context) {
+		if !strings.HasSuffix(ctx.Request.Host, domain) {
+			ctx.Next()
+			return
+		}
+
+		if ctx.Request.Host == domain && ctx.Request.URL.Path == "/" {
+			ctx.Redirect(http.StatusFound, fmt.Sprintf("http://%s.%s%s", uuid.New().String(), domain, redirectPort))
+			ctx.Abort()
+			return
+		}
+
+		handleDNS(ctx, store)
+		ctx.Abort()
+	}
+}
+
+func handleDNS(ctx *gin.Context, store *cache.Cache) {
+	d := strings.Split(ctx.Request.Host, ".")[0]
+	if !validator.IsValid(d) {
+		ctx.String(http.StatusNotFound, http.StatusText(http.StatusNotFound))
+		return
+	}
+
+	v, found := store.Get(d)
+	if !found {
+		ctx.String(http.StatusNotFound, http.StatusText(http.StatusNotFound))
+		return
+	}
+
+	ipStr, ok := v.(string)
+	if !ok {
+		ctx.String(http.StatusNotFound, http.StatusText(http.StatusNotFound))
+		return
+	}
+
+	ip := net.ParseIP(ipStr)
+	if ip == nil {
+		ctx.String(http.StatusNotFound, http.StatusText(http.StatusNotFound))
+		return
+	}
+
+	geo := service.Geo{IP: ip}
+	j := DNSJSONResponse{
+		DNS: dnsData{
+			IP:              ipStr,
+			Country:         geo.LookUpCity().Country.Names["en"],
+			AsnOrganization: geo.LookUpASN().AutonomousSystemOrganization,
+		},
+	}
+
+	switch ctx.NegotiateFormat(gin.MIMEPlain, gin.MIMEHTML, gin.MIMEJSON) {
+	case gin.MIMEJSON:
+		ctx.JSON(http.StatusOK, j)
+	default:
+		ctx.String(http.StatusOK, fmt.Sprintf("%s (%s / %s)\n", j.DNS.IP, j.DNS.Country, j.DNS.AsnOrganization))
+	}
+}

router/dns_test.go

@@ -0,0 +1,153 @@
+package router
+
+import (
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+	"strings"
+	"testing"
+
+	validator "github.com/dcarrillo/whatismyip/internal/validator/uuid"
+	"github.com/gin-gonic/gin"
+	"github.com/google/uuid"
+	"github.com/patrickmn/go-cache"
+	"github.com/stretchr/testify/assert"
+)
+
+func TestGetDNSDiscoveryHandler(t *testing.T) {
+	store := cache.New(cache.NoExpiration, cache.NoExpiration)
+	handler := GetDNSDiscoveryHandler(store, domain, "")
+
+	t.Run("calls next if host does not have domain suffix", func(t *testing.T) {
+		req, _ := http.NewRequest("GET", "/", nil)
+		req.Header.Set(trustedHeader, testIP.ipv4)
+		req.Host = "example.com"
+
+		w := httptest.NewRecorder()
+		c, _ := gin.CreateTestContext(w)
+		c.Request = req
+		handler(c)
+		app.ServeHTTP(w, req)
+
+		assert.Equal(t, http.StatusOK, w.Code)
+		assert.Equal(t, testIP.ipv4+"\n", w.Body.String())
+	})
+
+	t.Run("return 404 if there is a path", func(t *testing.T) {
+		req, _ := http.NewRequest("GET", "/path", nil)
+		req.Host = domain
+
+		w := httptest.NewRecorder()
+		c, _ := gin.CreateTestContext(w)
+		c.Request = req
+		handler(c)
+		app.ServeHTTP(w, req)
+
+		assert.Equal(t, http.StatusNotFound, w.Code)
+	})
+
+	t.Run("redirects if host is domain", func(t *testing.T) {
+		req, _ := http.NewRequest("GET", "/", nil)
+		req.Host = domain
+
+		w := httptest.NewRecorder()
+		c, _ := gin.CreateTestContext(w)
+		c.Request = req
+		handler(c)
+
+		assert.Equal(t, http.StatusFound, w.Code)
+		r, err := url.Parse(w.Header().Get("Location"))
+		assert.NoError(t, err)
+		assert.True(t, validator.IsValid(strings.Split(r.Host, ".")[0]))
+		assert.Equal(t, domain, strings.Join(strings.Split(r.Host, ".")[1:], "."))
+	})
+}
+
+func TestHandleDNS(t *testing.T) {
+	store := cache.New(cache.NoExpiration, cache.NoExpiration)
+	u := uuid.New().String()
+
+	tests := []struct {
+		name      string
+		subDomain string
+		stored    any
+	}{
+		{
+			name:      "not found if the subdomain is not a valid uuid",
+			subDomain: "not-uuid",
+			stored:    "",
+		},
+		{
+			name:      "not found if the ip is not found in the store",
+			subDomain: u,
+			stored:    "",
+		},
+		{
+			name:      "not found if the ip is in store but is not valid",
+			subDomain: u,
+			stored:    "bogus",
+		},
+		{
+			name:      "not found if the store contains no string",
+			subDomain: u,
+			stored:    20,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			req, _ := http.NewRequest("GET", "/", nil)
+			req.Host = tt.subDomain + "." + domain
+
+			if tt.stored != "" {
+				store.Add(tt.subDomain, tt.stored, cache.DefaultExpiration)
+			}
+
+			w := httptest.NewRecorder()
+			c, _ := gin.CreateTestContext(w)
+			c.Request = req
+			handleDNS(c, store)
+			assert.Equal(t, http.StatusNotFound, w.Code)
+		})
+	}
+}
+
+func TestAcceptDNSRequest(t *testing.T) {
+	store := cache.New(cache.NoExpiration, cache.NoExpiration)
+
+	tests := []struct {
+		name   string
+		accept string
+		want   string
+	}{
+		{
+			name:   "returns json dns data",
+			accept: "application/json",
+			want:   jsonDNSIPv4,
+		},
+		{
+			name:   "return plan text dns data",
+			accept: "text/plain",
+			want:   plainDNSIPv4,
+		},
+	}
+
+	for _, tt := range tests {
+		t.Run(tt.name, func(t *testing.T) {
+			req, _ := http.NewRequest("GET", "/", nil)
+			u := uuid.New().String()
+			req.Host = u + "." + domain
+			req.Header.Add("Accept", tt.accept)
+
+			w := httptest.NewRecorder()
+			c, _ := gin.CreateTestContext(w)
+			c.Request = req
+
+			store.Add(u, testIP.ipv4, cache.DefaultExpiration)
+			handleDNS(c, store)
+
+			assert.Equal(t, http.StatusOK, w.Code)
+			assert.Equal(t, tt.want, w.Body.String())
+		})
+	}
+}

router/generic.go

@@ -11,7 +11,6 @@ import (
 	"github.com/gin-gonic/gin"
 )
 
-// JSONResponse maps data as json
 type JSONResponse struct {
 	IP              string      `json:"ip"`
 	IPVersion       byte        `json:"ip_version"`

router/port_scanner.go

@@ -0,0 +1,54 @@
+package router
+
+import (
+	"fmt"
+	"net"
+	"net/http"
+	"strconv"
+
+	"github.com/dcarrillo/whatismyip/service"
+	"github.com/gin-gonic/gin"
+)
+
+type JSONScanResponse struct {
+	IP        string `json:"ip"`
+	Port      int    `json:"port"`
+	Reachable bool   `json:"reachable"`
+	Reason    string `json:"reason"`
+}
+
+func scanTCPPort(ctx *gin.Context) {
+	port, err := strconv.Atoi(ctx.Params.ByName("port"))
+	if err == nil && (port < 1 || port > 65535) {
+		err = fmt.Errorf("%d is not a valid port number", port)
+	}
+	if err != nil {
+		ctx.JSON(http.StatusBadRequest, JSONScanResponse{
+			Reason: err.Error(),
+		})
+		return
+	}
+
+	add := net.TCPAddr{
+		IP:   net.ParseIP(ctx.ClientIP()),
+		Port: port,
+	}
+
+	scan := service.PortScanner{
+		Address: &add,
+	}
+
+	isOpen, err := scan.IsPortOpen()
+	reason := ""
+	if err != nil {
+		reason = err.Error()
+	}
+
+	response := JSONScanResponse{
+		IP:        ctx.ClientIP(),
+		Port:      port,
+		Reachable: isOpen,
+		Reason:    reason,
+	}
+	ctx.JSON(http.StatusOK, response)
+}

router/setup.go

@@ -8,7 +8,6 @@ import (
 	"github.com/gin-gonic/gin"
 )
 
-// SetupTemplate reads and parses a template from file
 func SetupTemplate(r *gin.Engine) {
 	if setting.App.TemplatePath == "" {
 		t, _ := template.New("home").Parse(home)
@@ -19,9 +18,9 @@ func SetupTemplate(r *gin.Engine) {
 	}
 }
 
-// Setup defines the endpoints
 func Setup(r *gin.Engine) {
 	r.GET("/", getRoot)
+	r.GET("/scan/tcp/:port", scanTCPPort)
 	r.GET("/client-port", getClientPortAsString)
 	r.GET("/geo", getGeoAsString)
 	r.GET("/geo/:field", getGeoAsString)

router/setup_test.go

@@ -36,10 +36,15 @@ var (
 	}
 	jsonIPv4     = `{"client_port":"1001","ip":"81.2.69.192","ip_version":4,"country":"United Kingdom","country_code":"GB","city":"London","latitude":51.5142,"longitude":-0.0931,"postal_code":"","time_zone":"Europe/London","asn":0,"asn_organization":"","host":"test", "headers": {}}`
 	jsonIPv6     = `{"asn":3352, "asn_organization":"TELEFONICA DE ESPANA", "city":"", "client_port":"1001", "country":"", "country_code":"", "host":"test", "ip":"2a02:9000::1", "ip_version":6, "latitude":0, "longitude":0, "postal_code":"", "time_zone":"", "headers": {}}`
+	jsonDNSIPv4  = `{"dns":{"ip":"81.2.69.192","country":"United Kingdom","provider":""}}`
+	plainDNSIPv4 = "81.2.69.192 (United Kingdom / )\n"
 )
 
-const trustedHeader = "X-Real-IP"
+const (
-const trustedPortHeader = "X-Real-Port"
+	trustedHeader     = "X-Real-IP"
+	trustedPortHeader = "X-Real-Port"
+	domain            = "dns.example.com"
+)
 
 func TestMain(m *testing.M) {
 	app = gin.Default()

server/dns.go

@@ -0,0 +1,48 @@
+package server
+
+import (
+	"context"
+	"log"
+	"strconv"
+
+	"github.com/miekg/dns"
+)
+
+const port = 53
+
+type DNS struct {
+	server  *dns.Server
+	handler *dns.Handler
+	ctx     context.Context
+}
+
+func NewDNSServer(ctx context.Context, handler dns.Handler) *DNS {
+	return &DNS{
+		handler: &handler,
+		ctx:     ctx,
+	}
+}
+
+func (d *DNS) Start() {
+	d.server = &dns.Server{
+		Addr:    ":" + strconv.Itoa(port),
+		Net:     "udp",
+		Handler: *d.handler,
+		// UDPSize:   65535,
+		// ReusePort: true,
+	}
+
+	log.Printf("Starting DNS server listening on :%d (udp)", port)
+	go func() {
+		if err := d.server.ListenAndServe(); err != nil {
+			log.Fatal(err)
+		}
+	}()
+}
+
+func (d *DNS) Stop() {
+	log.Printf("Stopping DNS server...")
+	if err := d.server.Shutdown(); err != nil {
+		log.Printf("DNS server forced to shutdown: %s", err)
+	}
+}

server/quic.go

@@ -0,0 +1,55 @@
+package server
+
+import (
+	"context"
+	"errors"
+	"log"
+	"net/http"
+
+	"github.com/dcarrillo/whatismyip/internal/setting"
+	"github.com/quic-go/quic-go/http3"
+)
+
+type Quic struct {
+	server    *http3.Server
+	tlsServer *TLS
+	ctx       context.Context
+}
+
+func NewQuicServer(ctx context.Context, tlsServer *TLS) *Quic {
+	return &Quic{
+		tlsServer: tlsServer,
+		ctx:       ctx,
+	}
+}
+
+func (q *Quic) Start() {
+	q.server = &http3.Server{
+		Addr:    setting.App.TLSAddress,
+		Handler: q.tlsServer.server.Handler,
+	}
+
+	parentHandler := q.tlsServer.server.Handler
+	q.tlsServer.server.Handler = http.HandlerFunc(func(rw http.ResponseWriter, req *http.Request) {
+		if err := q.server.SetQuicHeaders(rw.Header()); err != nil {
+			log.Fatal(err)
+		}
+
+		parentHandler.ServeHTTP(rw, req)
+	})
+
+	log.Printf("Starting QUIC server listening on %s (udp)", setting.App.TLSAddress)
+	go func() {
+		if err := q.server.ListenAndServeTLS(setting.App.TLSCrtPath, setting.App.TLSKeyPath); err != nil &&
+			!errors.Is(err, http.ErrServerClosed) {
+			log.Fatal(err)
+		}
+	}()
+}
+
+func (q *Quic) Stop() {
+	log.Printf("Stopping QUIC server...")
+	if err := q.server.Close(); err != nil {
+		log.Printf("QUIC server forced to shutdown")
+	}
+}

server/server.go

@@ -0,0 +1,62 @@
+package server
+
+import (
+	"log"
+	"os"
+	"os/signal"
+	"syscall"
+
+	"github.com/dcarrillo/whatismyip/internal/setting"
+	"github.com/dcarrillo/whatismyip/models"
+)
+
+type Server interface {
+	Start()
+	Stop()
+}
+
+type Manager struct {
+	servers []Server
+}
+
+func Setup(servers []Server) *Manager {
+	return &Manager{
+		servers: servers,
+	}
+}
+
+func (m *Manager) Run() {
+	m.start()
+
+	models.Setup(setting.App.GeodbPath.City, setting.App.GeodbPath.ASN)
+	signalChan := make(chan os.Signal, len(m.servers))
+	signal.Notify(signalChan, syscall.SIGHUP, syscall.SIGINT, syscall.SIGTERM)
+	var s os.Signal
+	for {
+		s = <-signalChan
+
+		if s == syscall.SIGHUP {
+			m.stop()
+			models.CloseDBs()
+			models.Setup(setting.App.GeodbPath.City, setting.App.GeodbPath.ASN)
+			m.start()
+		} else {
+			log.Printf("Shutting down...")
+			m.stop()
+			models.CloseDBs()
+			break
+		}
+	}
+}
+
+func (m *Manager) start() {
+	for _, s := range m.servers {
+		s.Start()
+	}
+}
+
+func (m *Manager) stop() {
+	for _, s := range m.servers {
+		s.Stop()
+	}
+}

server/tcp.go

@@ -0,0 +1,46 @@
+package server
+
+import (
+	"context"
+	"errors"
+	"log"
+	"net/http"
+
+	"github.com/dcarrillo/whatismyip/internal/setting"
+)
+
+type TCP struct {
+	server  *http.Server
+	handler *http.Handler
+	ctx     context.Context
+}
+
+func NewTCPServer(ctx context.Context, handler *http.Handler) *TCP {
+	return &TCP{
+		handler: handler,
+		ctx:     ctx,
+	}
+}
+
+func (t *TCP) Start() {
+	t.server = &http.Server{
+		Addr:         setting.App.BindAddress,
+		Handler:      *t.handler,
+		ReadTimeout:  setting.App.Server.ReadTimeout,
+		WriteTimeout: setting.App.Server.WriteTimeout,
+	}
+
+	log.Printf("Starting TCP server listening on %s", setting.App.BindAddress)
+	go func() {
+		if err := t.server.ListenAndServe(); err != nil && !errors.Is(err, http.ErrServerClosed) {
+			log.Fatal(err)
+		}
+	}()
+}
+
+func (t *TCP) Stop() {
+	log.Printf("Stopping TCP server...")
+	if err := t.server.Shutdown(t.ctx); err != nil {
+		log.Printf("TCP server forced to shutdown: %s", err)
+	}
+}

server/tls.go

@@ -0,0 +1,47 @@
+package server
+
+import (
+	"context"
+	"errors"
+	"log"
+	"net/http"
+
+	"github.com/dcarrillo/whatismyip/internal/setting"
+)
+
+type TLS struct {
+	server  *http.Server
+	handler *http.Handler
+	ctx     context.Context
+}
+
+func NewTLSServer(ctx context.Context, handler *http.Handler) *TLS {
+	return &TLS{
+		handler: handler,
+		ctx:     ctx,
+	}
+}
+
+func (t *TLS) Start() {
+	t.server = &http.Server{
+		Addr:         setting.App.TLSAddress,
+		Handler:      *t.handler,
+		ReadTimeout:  setting.App.Server.ReadTimeout,
+		WriteTimeout: setting.App.Server.WriteTimeout,
+	}
+
+	log.Printf("Starting TLS server listening on %s", setting.App.TLSAddress)
+	go func() {
+		if err := t.server.ListenAndServeTLS(setting.App.TLSCrtPath, setting.App.TLSKeyPath); err != nil &&
+			!errors.Is(err, http.ErrServerClosed) {
+			log.Fatal(err)
+		}
+	}()
+}
+
+func (t *TLS) Stop() {
+	log.Printf("Stopping TLS server...")
+	if err := t.server.Shutdown(t.ctx); err != nil {
+		log.Printf("TLS server forced to shutdown: %s", err)
+	}
+}

service/port_scanner.go

@@ -0,0 +1,24 @@
+package service
+
+import (
+	"net"
+	"time"
+)
+
+const scannerTimeOut = 3 * time.Second
+
+type PortScanner struct {
+	Address net.Addr
+}
+
+func (p *PortScanner) IsPortOpen() (bool, error) {
+	conn, err := net.DialTimeout(p.Address.Network(), p.Address.String(), scannerTimeOut)
+	if err != nil {
+		return false, err
+	}
+	if conn != nil {
+		defer conn.Close()
+	}
+
+	return true, nil
+}

test/docker-compose.yml

@@ -0,0 +1,35 @@
+services:
+  whatismyip:
+    build:
+      context: ../
+      target: dev
+    ports:
+      - "8000:8000"
+      - "8001:8001"
+      - "8001:8001/udp"
+      - "53531:53/udp"
+    command:
+      - "-geoip2-city"
+      - "/GeoIP2-City-Test.mmdb"
+      - "-geoip2-asn"
+      - "/GeoLite2-ASN-Test.mmdb"
+      - "-bind"
+      - ":8000"
+      - "-tls-bind"
+      - ":8001"
+      - "-tls-crt"
+      - "/server.pem"
+      - "-tls-key"
+      - "/server.key"
+      - "-trusted-header"
+      - "X-Real-IP"
+      - "-enable-secure-headers"
+      - "-enable-http3"
+      - "-resolver"
+      - "/resolver.yml"
+    volumes:
+      - ./GeoIP2-City-Test.mmdb:/GeoIP2-City-Test.mmdb
+      - ./GeoLite2-ASN-Test.mmdb:/GeoLite2-ASN-Test.mmdb
+      - ./server.pem:/server.pem
+      - ./server.key:/server.key
+      - ./resolver.yml:/resolver.yml

test/resolver.yml

@@ -0,0 +1,10 @@
+---
+domain: dns.example.com
+redirect_port: ":8000"
+resource_records:
+  - "1800 IN SOA xns.example.com. hostmaster.example.com. 1 10000 2400 604800 1800"
+  - "3600 IN NS xns.example.com."
+ipv4:
+  - "127.0.0.2"
+ipv6:
+  - "aaa:aaa:aaa:aaaa::1"