feat: use ripedb for asn lookup

ripe/builder.go

@@ -0,0 +1,126 @@
+package ripe
+
+import (
+	"bufio"
+	"compress/gzip"
+	"errors"
+	"fmt"
+	"net"
+	"net/http"
+	"os"
+	"strings"
+
+	"github.com/maxmind/mmdbwriter"
+	"github.com/maxmind/mmdbwriter/mmdbtype"
+)
+
+type MMDBEntry struct {
+	Range string `json:"range",maxminddb:"range"`
+	ASN   string `json:"asn",maxminddb:"asn"`
+}
+
+const (
+	ripe4_download_url = "https://ftp.ripe.net/ripe/dbase/split/ripe.db.route.gz"
+	ripe6_download_url = "https://ftp.ripe.net/ripe/dbase/split/ripe.db.route6.gz"
+)
+
+func BuildNewMMDB(filepath string) error {
+	writer, err := mmdbwriter.New(
+		mmdbwriter.Options{
+			DatabaseType: "VOC-ASN-DB",
+			RecordSize:   32,
+		},
+	)
+	if err != nil {
+		return fmt.Errorf("error creating mmdb writer: %w", err)
+	}
+
+	if err := fillMMDB(writer, ripe4_download_url); err != nil {
+		return fmt.Errorf("error building IPv4 mmdb: %w", err)
+	}
+
+	if err := fillMMDB(writer, ripe6_download_url); err != nil {
+		return fmt.Errorf("error building IPv6 mmdb: %w", err)
+	}
+
+	fh, err := os.Create(filepath)
+	if err != nil {
+		return fmt.Errorf("error creating mmdb output file: %w", err)
+	}
+
+	if _, err = writer.WriteTo(fh); err != nil {
+		return fmt.Errorf("error writing mmdb to file: %w", err)
+	}
+
+	return nil
+}
+
+func fillMMDB(mmdb *mmdbwriter.Tree, url string) error {
+	// Fetch data from URL
+	resp, err := http.Get(url)
+	if err != nil {
+		return fmt.Errorf("error fetching data from %s: %w", url, err)
+	}
+	defer resp.Body.Close()
+
+	var s *bufio.Scanner
+
+	// Check if response is gzip compressed
+	reader, err := gzip.NewReader(resp.Body)
+	if err != nil {
+		s = bufio.NewScanner(resp.Body)
+	} else {
+		s = bufio.NewScanner(reader)
+		defer reader.Close()
+	}
+
+	var (
+		entries []MMDBEntry
+		entry   MMDBEntry
+	)
+
+	for tok := s.Scan(); tok; tok = s.Scan() {
+		//remove all spaces
+		line := strings.ReplaceAll(s.Text(), " ", "")
+
+		tokens := strings.Split(line, ":")
+
+		if len(tokens) != 2 {
+			continue
+		}
+
+		key := strings.TrimSpace(tokens[0])
+		if key == "route" {
+			entry = MMDBEntry{
+				Range: strings.TrimSpace(tokens[1]),
+			}
+		} else if key == "origin" {
+			entry.ASN = strings.TrimSpace(tokens[1])
+			entries = append(entries, entry)
+		}
+
+	}
+
+	if err := s.Err(); err != nil {
+		fmt.Printf("error scanning ripe file: %s", err)
+	}
+
+	var entrieErrors error
+	for _, e := range entries {
+		record := mmdbtype.Map{
+			"range": mmdbtype.String(e.Range),
+			"asn":   mmdbtype.String(e.ASN),
+		}
+
+		_, network, err := net.ParseCIDR(e.Range)
+		if err != nil {
+			errors.Join(entrieErrors, fmt.Errorf("error parsing CIDR: %w", err))
+			continue
+		}
+
+		err = mmdb.Insert(network, record)
+		errors.Join(entrieErrors, fmt.Errorf("error inserting record: %w", err))
+	}
+
+	return entrieErrors
+}