From b11d4ede6cbe25c2d9ab09ac8235fa18146ac092 Mon Sep 17 00:00:00 2001
From: core <core@coredoes.dev>
Date: Tue, 3 Oct 2023 13:54:57 -0400
Subject: [PATCH] load blackhole files

---
 blackhole.go                 | 15 +++++++
 cmd/pancheri-compile/main.go | 81 ++++++++++++++++++++++++++++++++++++
 cmd/pancheri/main.go         | 46 ++++++++++++++++++++
 config.go                    |  4 ++
 handler.go                   |  1 +
 5 files changed, 147 insertions(+)
 create mode 100644 blackhole.go
 create mode 100644 cmd/pancheri-compile/main.go

diff --git a/blackhole.go b/blackhole.go
new file mode 100644
index 0000000..afa9935
--- /dev/null
+++ b/blackhole.go
@@ -0,0 +1,15 @@
+package pancheri
+
+import "slices"
+
+type BlackholeFile struct {
+	DenyDomains []string `yaml:"deny_domains"`
+}
+
+type Blackholer struct {
+	DenyDomains []string
+}
+
+func (b *Blackholer) ShouldBlock(domain string) bool {
+	return slices.Contains(b.DenyDomains, domain)
+}
diff --git a/cmd/pancheri-compile/main.go b/cmd/pancheri-compile/main.go
new file mode 100644
index 0000000..c0932b4
--- /dev/null
+++ b/cmd/pancheri-compile/main.go
@@ -0,0 +1,81 @@
+package main
+
+import (
+	"flag"
+	"fmt"
+	"git.e3t.cc/e3team/pancheri"
+	"gopkg.in/yaml.v2"
+	"io"
+	"os"
+	"strings"
+	"time"
+)
+
+func main() {
+	hostsPath := flag.String("hostsfile", "", "Hosts file to convert to a dnsbl")
+	voidIp := flag.String("voidip", "0.0.0.0", "IP that this hosts file uses as a void IP")
+	printUsage := flag.Bool("help", false, "Print command line usage")
+
+	flag.Parse()
+
+	if *printUsage {
+		flag.Usage()
+		os.Exit(0)
+	}
+
+	f, err := os.Open(*hostsPath)
+	if err != nil {
+		fmt.Printf("error opening hosts file: %s", err)
+		os.Exit(1)
+	}
+
+	buf := new(strings.Builder)
+	_, err = io.Copy(buf, f)
+	if err != nil {
+		fmt.Printf("error reading hosts file: %s", err)
+		os.Exit(1)
+	}
+
+	err = f.Close()
+	if err != nil {
+		fmt.Printf("error closing hosts file: %s", err)
+		os.Exit(1)
+	}
+
+	split := strings.Split(buf.String(), "\n")
+
+	blackhole := pancheri.BlackholeFile{
+		DenyDomains: *new([]string),
+	}
+
+	for _, line := range split {
+		if strings.HasPrefix(line, "#") {
+			continue
+		}
+		if line == "" {
+			continue
+		}
+		if !strings.HasPrefix(line, *voidIp) {
+			continue
+		}
+
+		lineSplit := strings.Split(line, " ")
+
+		if strings.Join(lineSplit[1:], " ") == *voidIp {
+			continue
+		}
+
+		blackhole.DenyDomains = append(blackhole.DenyDomains, strings.Join(lineSplit[1:], " "))
+	}
+
+	marshaled, err := yaml.Marshal(blackhole)
+
+	if err != nil {
+		fmt.Printf("error saving blacklist file: %s", err)
+		os.Exit(1)
+	}
+
+	fmt.Printf("# Compiled by pancheri-compile at %s\n", time.Now().Format(time.RFC3339))
+	fmt.Printf("# %d hosts loaded from %s\n", len(blackhole.DenyDomains), *hostsPath)
+	fmt.Printf("%s", marshaled)
+}
diff --git a/cmd/pancheri/main.go b/cmd/pancheri/main.go
index 0e03f48..66b214f 100644
--- a/cmd/pancheri/main.go
+++ b/cmd/pancheri/main.go
@@ -6,6 +6,7 @@ import (
 	"git.e3t.cc/e3team/pancheri"
 	"github.com/miekg/dns"
 	"github.com/sirupsen/logrus"
+	"gopkg.in/yaml.v2"
 	"os"
 )
 
@@ -65,6 +66,51 @@ func main() {
 		r = pancheri.NewResolver(c.Resolver.Upstream)
 	}
 
+	var b *pancheri.Blackholer
+
+	if c.Blackhole.Enable {
+		logrus.WithFields(logrus.Fields{
+			"denyfiles": len(c.Blackhole.BlockLists),
+		}).Info("enabling blackholer")
+
+		b = &pancheri.Blackholer{
+			DenyDomains: *new([]string),
+		}
+
+		for _, file := range c.Blackhole.BlockLists {
+			logrus.WithFields(logrus.Fields{
+				"file": file,
+			}).Info("loading blocklist")
+
+			f, err := os.Open(file)
+			if err != nil {
+				logrus.Errorf("error loading blocklist file: %s", err)
+			}
+
+			var cfg pancheri.BlackholeFile
+			decoder := yaml.NewDecoder(f)
+
+			err = decoder.Decode(&cfg)
+			if err != nil {
+				logrus.Errorf("error decoding blocklist file: %s", err)
+			}
+
+			err = f.Close()
+			if err != nil {
+				logrus.Errorf("error closing blocklist file: %s", err)
+			}
+
+			b.DenyDomains = append(b.DenyDomains, cfg.DenyDomains...)
+			logrus.WithFields(logrus.Fields{
+				"file": file,
+			}).Infof("loaded %d hosts", len(cfg.DenyDomains))
+		}
+
+		logrus.WithFields(logrus.Fields{
+			"hosts": len(b.DenyDomains),
+		}).Info("blackhole enabled")
+	}
+
 	handler := pancheri.Handler{
 		C: c,
 		R: r,
diff --git a/config.go b/config.go
index b268a73..e6ed735 100644
--- a/config.go
+++ b/config.go
@@ -22,6 +22,10 @@ type Config struct {
 	Zone struct {
 		LoadFiles []string `yaml:"load_files"`
 	} `yaml:"zone"`
+	Blackhole struct {
+		Enable     bool     `yaml:"enable"`
+		BlockLists []string `yaml:"block_lists"`
+	}
 }
 
 func LoadConfig(path string) (*Config, error) {
diff --git a/handler.go b/handler.go
index c2a688b..021ccba 100644
--- a/handler.go
+++ b/handler.go
@@ -10,6 +10,7 @@ type Handler struct {
 	C *Config
 	R *Resolver
 	A *Authority
+	B *Blackholer
 }
 
 func (h *Handler) ServeDNS(w dns.ResponseWriter, r *dns.Msg) {