Enable download of GeoLite2 databases

cmd/nginx/flags.go

@@ -181,6 +181,9 @@ Takes the form "<host>:port". If not provided, no admission controller is starte
 
 	flags.MarkDeprecated("enable-dynamic-certificates", `Only dynamic mode is supported`)
 
+	flags.StringVar(&nginx.MaxmindLicenseKey, "maxmind-license-key", "", `Maxmind license key to download GeoLite2 Databases.
+https://blog.maxmind.com/2019/12/18/significant-changes-to-accessing-and-using-geolite2-databases`)
+
 	flag.Set("logtostderr", "true")
 
 	flags.AddGoFlagSet(flag.CommandLine)
@@ -297,5 +300,13 @@ Takes the form "<host>:port". If not provided, no admission controller is starte
 		config.RootCAFile = *rootCAFile
 	}
 
+	if nginx.MaxmindLicenseKey != "" {
+		klog.Info("downloading maxmind GeoIP2 databases...")
+		err := nginx.DownloadGeoLite2DB()
+		if err != nil {
+			klog.Errorf("unexpected error downloading GeoIP2 database: %v", err)
+		}
+	}
+
 	return false, config, nil
 }

docs/user-guide/nginx-configuration/configmap.md

@@ -557,6 +557,13 @@ _**default:**_ true
 ## use-geoip2
 
 Enables the [geoip2 module](https://github.com/leev/ngx_http_geoip2_module) for NGINX.
+Since `0.27.0` and due to a [change in the MaxMind databases](https://blog.maxmind.com/2019/12/18/significant-changes-to-accessing-and-using-geolite2-databases) a license is required to have access to the databases.
+For this reason, it is required to define a new flag `--maxmind-license-key` in the ingress controller deployment to download the databases needed during the initialization of the ingress controller.
+Alternatively, it is possible to use a volume to mount the files `/etc/nginx/geoip/GeoLite2-City.mmdb` and `/etc/nginx/geoip/GeoLite2-ASN.mmdb`, avoiding the overhead of the download.
+
+!!! Important
+    If the feature is enabled but the files are missing, GeoIP2 will not be enabled.
+
 _**default:**_ false
 
 ## enable-brotli

internal/ingress/controller/store/store.go

@@ -54,6 +54,7 @@ import (
 	"k8s.io/ingress-nginx/internal/ingress/errors"
 	"k8s.io/ingress-nginx/internal/ingress/resolver"
 	"k8s.io/ingress-nginx/internal/k8s"
+	"k8s.io/ingress-nginx/internal/nginx"
 )
 
 // IngressFilterFunc decides if an Ingress should be omitted or not
@@ -896,6 +897,11 @@ func (s *k8sStore) setConfig(cmap *corev1.ConfigMap) {
 	}
 
 	s.backendConfig = ngx_template.ReadConfig(cmap.Data)
+	if s.backendConfig.UseGeoIP2 && !nginx.GeoLite2DBExists() {
+		klog.Warning("The GeoIP2 feature is enabled but the databases are missing. Disabling.")
+		s.backendConfig.UseGeoIP2 = false
+	}
+
 	s.writeSSLSessionTicketKey(cmap, "/etc/nginx/tickets.key")
 }
 

internal/nginx/maxmind.go

@@ -0,0 +1,143 @@
+/*
+Copyright 2020 The Kubernetes Authors.
+
+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 nginx
+
+import (
+	"archive/tar"
+	"compress/gzip"
+	"fmt"
+	"io"
+	"net/http"
+	"os"
+	"path"
+	"strings"
+)
+
+// MaxmindLicenseKey maxmind license key to download databases
+var MaxmindLicenseKey = ""
+
+const (
+	geoIPPath = "/etc/nginx/geoip"
+
+	geoLiteCityDB = "GeoLite2-City"
+	geoLiteASNDB  = "GeoLite2-ASN"
+
+	dbExtension = ".mmdb"
+
+	maxmindURL = "https://download.maxmind.com/app/geoip_download?license_key=%v&edition_id=%v&suffix=tar.gz"
+)
+
+// GeoLite2DBExists checks if the required databases for
+// the GeoIP2 NGINX module are present in the filesystem
+func GeoLite2DBExists() bool {
+	if !fileExists(path.Join(geoIPPath, geoLiteASNDB+dbExtension)) {
+		return false
+	}
+
+	if !fileExists(path.Join(geoIPPath, geoLiteCityDB+dbExtension)) {
+		return false
+	}
+
+	return true
+}
+
+// DownloadGeoLite2DB downloads the required databases by the
+// GeoIP2 NGINX module using a license key from MaxMind.
+func DownloadGeoLite2DB() error {
+	err := downloadDatabase(geoLiteCityDB)
+	if err != nil {
+		return err
+	}
+
+	err = downloadDatabase(geoLiteASNDB)
+	if err != nil {
+		return err
+	}
+
+	return nil
+}
+
+func downloadDatabase(dbName string) error {
+	url := fmt.Sprintf(maxmindURL, MaxmindLicenseKey, dbName)
+	req, err := http.NewRequest(http.MethodGet, url, nil)
+	if err != nil {
+		return err
+	}
+
+	resp, err := http.DefaultClient.Do(req)
+	if err != nil {
+		return err
+	}
+
+	defer resp.Body.Close()
+
+	if resp.StatusCode != http.StatusOK {
+		return fmt.Errorf("HTTP status %v", resp.Status)
+	}
+
+	archive, err := gzip.NewReader(resp.Body)
+	if err != nil {
+		return err
+	}
+	defer archive.Close()
+
+	mmdbFile := dbName + dbExtension
+
+	tarReader := tar.NewReader(archive)
+	for true {
+		header, err := tarReader.Next()
+		if err == io.EOF {
+			break
+		}
+
+		if err != nil {
+			return err
+		}
+
+		switch header.Typeflag {
+		case tar.TypeReg:
+			if !strings.HasSuffix(header.Name, mmdbFile) {
+				continue
+			}
+
+			outFile, err := os.Create(path.Join(geoIPPath, mmdbFile))
+			if err != nil {
+				return err
+			}
+
+			defer outFile.Close()
+
+			if _, err := io.Copy(outFile, tarReader); err != nil {
+				return err
+			}
+
+			return nil
+		}
+	}
+
+	return fmt.Errorf("the URL %v does not contains the database %v",
+		fmt.Sprintf(maxmindURL, "XXXXXXX", dbName), mmdbFile)
+}
+
+func fileExists(filePath string) bool {
+	info, err := os.Stat(filePath)
+	if os.IsNotExist(err) {
+		return false
+	}
+
+	return !info.IsDir()
+}