badguardhome/control.go

1531 lines
41 KiB
Go

package main
import (
"bytes"
"encoding/json"
"fmt"
"io/ioutil"
"log"
"net"
"net/http"
"os"
"os/exec"
"path/filepath"
"regexp"
"strconv"
"strings"
"syscall"
"time"
"github.com/AdguardTeam/AdguardDNS/dnsfilter"
"github.com/miekg/dns"
"gopkg.in/asaskevich/govalidator.v4"
)
const updatePeriod = time.Minute * 30
var coreDNSCommand *exec.Cmd
var filterTitle = regexp.MustCompile(`^! Title: +(.*)$`)
// cached version.json to avoid hammering github.io for each page reload
var versionCheckJSON []byte
var versionCheckLastTime time.Time
const versionCheckURL = "https://adguardteam.github.io/AdguardDNS/version.json"
const versionCheckPeriod = time.Hour * 8
// -------------------
// coredns run control
// -------------------
func tellCoreDNSToReload() {
// not running -- cheap check
if coreDNSCommand == nil && coreDNSCommand.Process == nil {
return
}
// not running -- more expensive check
if !isRunning() {
return
}
pid := coreDNSCommand.Process.Pid
process, err := os.FindProcess(pid)
if err != nil {
log.Printf("os.FindProcess(%d) returned err: %v\n", pid, err)
return
}
err = process.Signal(syscall.SIGUSR1)
if err != nil {
log.Printf("process.Signal on pid %d returned: %v\n", pid, err)
return
}
}
func writeAllConfigsAndReloadCoreDNS() error {
err := writeAllConfigs()
if err != nil {
log.Printf("Couldn't write all configs: %s", err)
return err
}
tellCoreDNSToReload()
return nil
}
func isRunning() bool {
if coreDNSCommand != nil && coreDNSCommand.Process != nil {
pid := coreDNSCommand.Process.Pid
process, err := os.FindProcess(pid)
if err != nil {
log.Printf("os.FindProcess(%d) returned err: %v\n", pid, err)
} else {
err := process.Signal(syscall.Signal(0))
if err != nil {
log.Printf("process.Signal on pid %d returned: %v\n", pid, err)
}
if err == nil {
return true
}
}
}
return false
}
func startDNSServer() error {
if isRunning() {
return fmt.Errorf("Unable to start coreDNS: Already running")
}
err := writeCoreDNSConfig()
if err != nil {
errortext := fmt.Errorf("Unable to write coredns config: %s", err)
log.Println(errortext)
return errortext
}
err = writeFilterFile()
if err != nil {
errortext := fmt.Errorf("Couldn't write filter file: %s", err)
log.Println(errortext)
return errortext
}
binarypath := filepath.Join(config.ourBinaryDir, config.CoreDNS.binaryFile)
configpath := filepath.Join(config.ourBinaryDir, config.CoreDNS.coreFile)
coreDNSCommand = exec.Command(binarypath, "-conf", configpath, "-dns.port", fmt.Sprintf("%d", config.CoreDNS.Port))
coreDNSCommand.Stdout = os.Stdout
coreDNSCommand.Stderr = os.Stderr
err = coreDNSCommand.Start()
if err != nil {
errortext := fmt.Errorf("Unable to start coreDNS: %s", err)
log.Println(errortext)
return errortext
}
log.Printf("coredns PID: %v\n", coreDNSCommand.Process.Pid)
go childwaiter()
return nil
}
func handleStart(w http.ResponseWriter, r *http.Request) {
if isRunning() {
http.Error(w, fmt.Sprintf("Unable to start coreDNS: Already running"), 400)
return
}
err := startDNSServer()
if err != nil {
http.Error(w, err.Error(), http.StatusInternalServerError)
return
}
_, err = fmt.Fprintf(w, "OK, PID %d\n", coreDNSCommand.Process.Pid)
if err != nil {
log.Printf("Couldn't write body in %s(): %s", _Func(), err)
return
}
}
func childwaiter() {
err := coreDNSCommand.Wait()
log.Printf("coredns terminated: %s\n", err)
err = coreDNSCommand.Process.Release()
log.Printf("coredns released: %s\n", err)
}
func handleStop(w http.ResponseWriter, r *http.Request) {
if coreDNSCommand == nil || coreDNSCommand.Process == nil {
http.Error(w, fmt.Sprintf("Unable to start coreDNS: Not running"), 400)
return
}
if isRunning() {
http.Error(w, fmt.Sprintf("Unable to start coreDNS: Not running"), 400)
return
}
cmd := coreDNSCommand
// TODO: send SIGTERM first, then SIGKILL
err := cmd.Process.Kill()
if err != nil {
errortext := fmt.Sprintf("Unable to stop coreDNS:\nGot error %T\n%v\n%s", err, err, err)
log.Println(errortext)
http.Error(w, errortext, 500)
return
}
exitstatus := cmd.Wait()
err = cmd.Process.Release()
if err != nil {
errortext := fmt.Sprintf("Unable to release process resources: %s", err)
log.Println(errortext)
http.Error(w, errortext, 500)
return
}
_, err = fmt.Fprintf(w, "OK\n%s\n", exitstatus)
if err != nil {
log.Printf("Couldn't write body in %s(): %s", _Func(), err)
return
}
}
func handleRestart(w http.ResponseWriter, r *http.Request) {
handleStop(w, r)
handleStart(w, r)
}
func handleStatus(w http.ResponseWriter, r *http.Request) {
data := map[string]interface{}{
"running": isRunning(),
"version": VersionString,
"dns_address": config.BindHost,
"dns_port": config.CoreDNS.Port,
"querylog_enabled": config.CoreDNS.QueryLogEnabled,
"upstream_dns": config.CoreDNS.UpstreamDNS,
}
json, err := json.Marshal(data)
if err != nil {
errortext := fmt.Sprintf("Unable to marshal status json: %s", err)
log.Println(errortext)
http.Error(w, errortext, 500)
return
}
w.Header().Set("Content-Type", "application/json")
_, err = w.Write(json)
if err != nil {
errortext := fmt.Sprintf("Unable to write response json: %s", err)
log.Println(errortext)
http.Error(w, errortext, 500)
return
}
}
// -----
// stats
// -----
func handleStats(w http.ResponseWriter, r *http.Request) {
histrical := generateMapFromStats(&statistics.PerHour, 0, 24)
// sum them up
summed := map[string]interface{}{}
for key, values := range histrical {
summedValue := 0.0
floats, ok := values.([]float64)
if !ok {
continue
}
for _, v := range floats {
summedValue += v
}
summed[key] = summedValue
}
summed["stats_period"] = "24 hours"
json, err := json.Marshal(summed)
if err != nil {
errortext := fmt.Sprintf("Unable to marshal status json: %s", err)
log.Println(errortext)
http.Error(w, errortext, 500)
return
}
w.Header().Set("Content-Type", "application/json")
_, err = w.Write(json)
if err != nil {
errortext := fmt.Sprintf("Unable to write response json: %s", err)
log.Println(errortext)
http.Error(w, errortext, 500)
return
}
}
func handleStatsHistory(w http.ResponseWriter, r *http.Request) {
// handle time unit and prepare our time window size
now := time.Now()
timeUnitString := r.URL.Query().Get("time_unit")
var stats *periodicStats
var timeUnit time.Duration
switch timeUnitString {
case "seconds":
timeUnit = time.Second
stats = &statistics.PerSecond
case "minutes":
timeUnit = time.Minute
stats = &statistics.PerMinute
case "hours":
timeUnit = time.Hour
stats = &statistics.PerHour
case "days":
timeUnit = time.Hour * 24
stats = &statistics.PerDay
default:
http.Error(w, "Must specify valid time_unit parameter", 400)
return
}
// parse start and end time
startTime, err := time.Parse(time.RFC3339, r.URL.Query().Get("start_time"))
if err != nil {
errortext := fmt.Sprintf("Must specify valid start_time parameter: %s", err)
log.Println(errortext)
http.Error(w, errortext, 400)
return
}
endTime, err := time.Parse(time.RFC3339, r.URL.Query().Get("end_time"))
if err != nil {
errortext := fmt.Sprintf("Must specify valid end_time parameter: %s", err)
log.Println(errortext)
http.Error(w, errortext, 400)
return
}
// check if start and time times are within supported time range
timeRange := timeUnit * statsHistoryElements
if startTime.Add(timeRange).Before(now) {
http.Error(w, "start_time parameter is outside of supported range", 501)
return
}
if endTime.Add(timeRange).Before(now) {
http.Error(w, "end_time parameter is outside of supported range", 501)
return
}
// calculate start and end of our array
// basically it's how many hours/minutes/etc have passed since now
start := int(now.Sub(endTime) / timeUnit)
end := int(now.Sub(startTime) / timeUnit)
// swap them around if they're inverted
if start > end {
start, end = end, start
}
data := generateMapFromStats(stats, start, end)
json, err := json.Marshal(data)
if err != nil {
errortext := fmt.Sprintf("Unable to marshal status json: %s", err)
log.Println(errortext)
http.Error(w, errortext, 500)
return
}
w.Header().Set("Content-Type", "application/json")
_, err = w.Write(json)
if err != nil {
errortext := fmt.Sprintf("Unable to write response json: %s", err)
log.Println(errortext)
http.Error(w, errortext, 500)
return
}
}
func handleQueryLog(w http.ResponseWriter, r *http.Request) {
isDownload := r.URL.Query().Get("download") != ""
resp, err := client.Get("http://127.0.0.1:8618/querylog")
if err != nil {
errortext := fmt.Sprintf("Couldn't get querylog from coredns: %T %s\n", err, err)
log.Println(errortext)
http.Error(w, errortext, http.StatusBadGateway)
return
}
if resp != nil && resp.Body != nil {
defer resp.Body.Close()
}
// read the body entirely
body, err := ioutil.ReadAll(resp.Body)
if err != nil {
errortext := fmt.Sprintf("Couldn't read response body: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusBadGateway)
return
}
// forward body entirely with status code
w.Header().Set("Content-Type", "application/json")
w.Header().Set("Content-Length", strconv.Itoa(len(body)))
if isDownload {
w.Header().Set("Content-Disposition", "attachment; filename=querylog.json")
}
w.WriteHeader(resp.StatusCode)
_, err = w.Write(body)
if err != nil {
errortext := fmt.Sprintf("Couldn't write body: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
}
}
func handleQueryLogEnable(w http.ResponseWriter, r *http.Request) {
config.CoreDNS.QueryLogEnabled = true
err := writeAllConfigsAndReloadCoreDNS()
if err != nil {
errortext := fmt.Sprintf("Couldn't write config file: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
return
}
_, err = fmt.Fprintf(w, "OK\n")
if err != nil {
errortext := fmt.Sprintf("Couldn't write body: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
}
}
func handleQueryLogDisable(w http.ResponseWriter, r *http.Request) {
config.CoreDNS.QueryLogEnabled = false
err := writeAllConfigsAndReloadCoreDNS()
if err != nil {
errortext := fmt.Sprintf("Couldn't write config file: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
return
}
_, err = fmt.Fprintf(w, "OK\n")
if err != nil {
errortext := fmt.Sprintf("Couldn't write body: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
}
}
func handleStatsReset(w http.ResponseWriter, r *http.Request) {
purgeStats()
_, err := fmt.Fprintf(w, "OK\n")
if err != nil {
httpError(w, http.StatusInternalServerError, "Couldn't write body: %s", err)
return
}
}
func handleStatsTop(w http.ResponseWriter, r *http.Request) {
resp, err := client.Get("http://127.0.0.1:8618/querylog")
if err != nil {
errortext := fmt.Sprintf("Couldn't get querylog from coredns: %T %s\n", err, err)
log.Println(errortext)
http.Error(w, errortext, http.StatusBadGateway)
return
}
if resp != nil && resp.Body != nil {
defer resp.Body.Close()
}
// read body
body, err := ioutil.ReadAll(resp.Body)
if err != nil {
errortext := fmt.Sprintf("Couldn't read response body: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusBadGateway)
return
}
// empty body
if len(body) == 0 {
return
}
values := []interface{}{}
err = json.Unmarshal(body, &values)
if err != nil {
errortext := fmt.Sprintf("Couldn't parse response body: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusBadGateway)
return
}
domains := map[string]int{}
blocked := map[string]int{}
clients := map[string]int{}
now := time.Now()
timeWindow := time.Hour * 24
notBefore := now.Add(timeWindow * -1)
for _, value := range values {
entry, ok := value.(map[string]interface{})
if !ok {
// ignore anything else
continue
}
host := getHost(entry)
reason := getReason(entry)
client := getClient(entry)
time := getTime(entry)
if time.Before(notBefore) {
// skip if the entry is before specified cutoff
continue
}
if len(host) > 0 {
domains[host]++
}
if len(host) > 0 && strings.HasPrefix(reason, "Filtered") {
blocked[host]++
}
if len(client) > 0 {
clients[client]++
}
}
// use manual json marshalling because we want maps to be sorted by value
json := bytes.Buffer{}
json.WriteString("{\n")
gen := func(json *bytes.Buffer, name string, top map[string]int, addComma bool) {
json.WriteString(" \"")
json.WriteString(name)
json.WriteString("\": {\n")
sorted := sortByValue(top)
for i, key := range sorted {
json.WriteString(" \"")
json.WriteString(key)
json.WriteString("\": ")
json.WriteString(strconv.Itoa(top[key]))
if i+1 != len(sorted) {
json.WriteByte(',')
}
json.WriteByte('\n')
}
json.WriteString(" }")
if addComma {
json.WriteByte(',')
}
json.WriteByte('\n')
}
gen(&json, "top_queried_domains", domains, true)
gen(&json, "top_blocked_domains", blocked, true)
gen(&json, "top_clients", clients, true)
json.WriteString(" \"stats_period\": \"24 hours\"\n")
json.WriteString("}\n")
w.Header().Set("Content-Type", "application/json")
_, err = w.Write(json.Bytes())
if err != nil {
errortext := fmt.Sprintf("Couldn't write body: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
}
}
func httpError(w http.ResponseWriter, code int, format string, args ...interface{}) {
text := fmt.Sprintf(format, args...)
http.Error(w, text, code)
}
func handleSetUpstreamDNS(w http.ResponseWriter, r *http.Request) {
body, err := ioutil.ReadAll(r.Body)
if err != nil {
errortext := fmt.Sprintf("Failed to read request body: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusBadRequest)
return
}
// if empty body -- user is asking for default servers
hosts, err := sanitiseDNSServers(string(body))
if err != nil {
httpError(w, http.StatusBadRequest, "Invalid DNS servers were given: %s", err)
return
}
if len(hosts) == 0 {
config.CoreDNS.UpstreamDNS = defaultDNS
} else {
config.CoreDNS.UpstreamDNS = hosts
}
err = writeAllConfigs()
if err != nil {
errortext := fmt.Sprintf("Couldn't write config file: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
return
}
tellCoreDNSToReload()
_, err = fmt.Fprintf(w, "OK %d servers\n", len(hosts))
if err != nil {
errortext := fmt.Sprintf("Couldn't write body: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
}
}
func handleTestUpstreamDNS(w http.ResponseWriter, r *http.Request) {
body, err := ioutil.ReadAll(r.Body)
if err != nil {
errortext := fmt.Sprintf("Failed to read request body: %s", err)
log.Println(errortext)
http.Error(w, errortext, 400)
return
}
hosts := strings.Fields(string(body))
if len(hosts) == 0 {
errortext := fmt.Sprintf("No servers specified")
log.Println(errortext)
http.Error(w, errortext, http.StatusBadRequest)
return
}
result := map[string]string{}
for _, host := range hosts {
err := checkDNS(host)
if err != nil {
log.Println(err)
result[host] = err.Error()
} else {
result[host] = "OK"
}
}
json, err := json.Marshal(result)
if err != nil {
errortext := fmt.Sprintf("Unable to marshal status json: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
return
}
w.Header().Set("Content-Type", "application/json")
_, err = w.Write(json)
if err != nil {
errortext := fmt.Sprintf("Couldn't write body: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
}
}
func checkDNS(input string) error {
input, err := sanitizeDNSServer(input)
if err != nil {
return err
}
req := dns.Msg{}
req.Id = dns.Id()
req.RecursionDesired = true
req.Question = []dns.Question{
{"google-public-dns-a.google.com.", dns.TypeA, dns.ClassINET},
}
prefix, host := splitDNSServerPrefixServer(input)
c := dns.Client{
Timeout: time.Minute,
}
switch prefix {
case "tls://":
c.Net = "tcp-tls"
}
resp, rtt, err := c.Exchange(&req, host)
if err != nil {
return fmt.Errorf("Couldn't communicate with DNS server %s: %s", input, err)
}
trace("exchange with %s took %v", input, rtt)
if len(resp.Answer) != 1 {
return fmt.Errorf("DNS server %s returned wrong answer", input)
}
if t, ok := resp.Answer[0].(*dns.A); ok {
if !net.IPv4(8, 8, 8, 8).Equal(t.A) {
return fmt.Errorf("DNS server %s returned wrong answer: %v", input, t.A)
}
}
return nil
}
func sanitiseDNSServers(input string) ([]string, error) {
fields := strings.Fields(input)
hosts := []string{}
for _, field := range fields {
sanitized, err := sanitizeDNSServer(field)
if err != nil {
return hosts, err
}
hosts = append(hosts, sanitized)
}
return hosts, nil
}
func getDNSServerPrefix(input string) string {
prefix := ""
switch {
case strings.HasPrefix(input, "dns://"):
prefix = "dns://"
case strings.HasPrefix(input, "tls://"):
prefix = "tls://"
}
return prefix
}
func splitDNSServerPrefixServer(input string) (string, string) {
prefix := getDNSServerPrefix(input)
host := strings.TrimPrefix(input, prefix)
return prefix, host
}
func sanitizeDNSServer(input string) (string, error) {
prefix, host := splitDNSServerPrefixServer(input)
host = appendPortIfMissing(prefix, host)
{
h, _, err := net.SplitHostPort(host)
if err != nil {
return "", err
}
ip := net.ParseIP(h)
if ip == nil {
return "", fmt.Errorf("Invalid DNS server field: %s", h)
}
}
return prefix + host, nil
}
func appendPortIfMissing(prefix, input string) string {
port := "53"
switch prefix {
case "tls://":
port = "853"
}
_, _, err := net.SplitHostPort(input)
if err == nil {
return input
}
return net.JoinHostPort(input, port)
}
func handleGetVersionJSON(w http.ResponseWriter, r *http.Request) {
now := time.Now()
if now.Sub(versionCheckLastTime) <= versionCheckPeriod && len(versionCheckJSON) != 0 {
// return cached copy
w.Header().Set("Content-Type", "application/json")
w.Write(versionCheckJSON)
return
}
resp, err := client.Get(versionCheckURL)
if err != nil {
errortext := fmt.Sprintf("Couldn't get querylog from coredns: %T %s\n", err, err)
log.Println(errortext)
http.Error(w, errortext, http.StatusBadGateway)
return
}
if resp != nil && resp.Body != nil {
defer resp.Body.Close()
}
// read the body entirely
body, err := ioutil.ReadAll(resp.Body)
if err != nil {
errortext := fmt.Sprintf("Couldn't read response body: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusBadGateway)
return
}
w.Header().Set("Content-Type", "application/json")
_, err = w.Write(body)
if err != nil {
errortext := fmt.Sprintf("Couldn't write body: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
}
versionCheckLastTime = now
versionCheckJSON = body
}
// ---------
// filtering
// ---------
func handleFilteringEnable(w http.ResponseWriter, r *http.Request) {
config.CoreDNS.FilteringEnabled = true
err := writeAllConfigsAndReloadCoreDNS()
if err != nil {
errortext := fmt.Sprintf("Couldn't write config file: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
return
}
_, err = fmt.Fprintf(w, "OK\n")
if err != nil {
errortext := fmt.Sprintf("Couldn't write body: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
}
}
func handleFilteringDisable(w http.ResponseWriter, r *http.Request) {
config.CoreDNS.FilteringEnabled = false
err := writeAllConfigsAndReloadCoreDNS()
if err != nil {
errortext := fmt.Sprintf("Couldn't write config file: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
return
}
_, err = fmt.Fprintf(w, "OK\n")
if err != nil {
errortext := fmt.Sprintf("Couldn't write body: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
}
}
func handleFilteringStatus(w http.ResponseWriter, r *http.Request) {
data := map[string]interface{}{
"enabled": config.CoreDNS.FilteringEnabled,
}
config.RLock()
data["filters"] = config.Filters
data["user_rules"] = config.UserRules
json, err := json.Marshal(data)
config.RUnlock()
if err != nil {
errortext := fmt.Sprintf("Unable to marshal status json: %s", err)
log.Println(errortext)
http.Error(w, errortext, 500)
return
}
w.Header().Set("Content-Type", "application/json")
_, err = w.Write(json)
if err != nil {
errortext := fmt.Sprintf("Unable to write response json: %s", err)
log.Println(errortext)
http.Error(w, errortext, 500)
return
}
}
func handleFilteringAddURL(w http.ResponseWriter, r *http.Request) {
parameters, err := parseParametersFromBody(r.Body)
if err != nil {
errortext := fmt.Sprintf("failed to parse parameters from body: %s", err)
log.Println(errortext)
http.Error(w, errortext, 400)
return
}
url, ok := parameters["url"]
if !ok {
http.Error(w, "URL parameter was not specified", 400)
return
}
if valid := govalidator.IsRequestURL(url); !valid {
http.Error(w, "URL parameter is not valid request URL", 400)
return
}
// check for duplicates
for i := range config.Filters {
filter := &config.Filters[i]
if filter.URL == url {
errortext := fmt.Sprintf("Filter URL already added -- %s", url)
log.Println(errortext)
http.Error(w, errortext, http.StatusBadRequest)
return
}
}
var filter = filter{
Enabled: true,
URL: url,
}
ok, err = filter.update(time.Now())
if err != nil {
errortext := fmt.Sprintf("Couldn't fetch filter from url %s: %s", url, err)
log.Println(errortext)
http.Error(w, errortext, http.StatusBadRequest)
return
}
if filter.RulesCount == 0 {
errortext := fmt.Sprintf("Filter at url %s has no rules (maybe it points to blank page?)", url)
log.Println(errortext)
http.Error(w, errortext, http.StatusBadRequest)
return
}
if !ok {
errortext := fmt.Sprintf("Filter at url %s is invalid (maybe it points to blank page?)", url)
log.Println(errortext)
http.Error(w, errortext, http.StatusBadRequest)
return
}
// URL is deemed valid, append it to filters, update config, write new filter file and tell coredns to reload it
config.Filters = append(config.Filters, filter)
err = writeAllConfigs()
if err != nil {
errortext := fmt.Sprintf("Couldn't write config file: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
return
}
err = writeFilterFile()
if err != nil {
errortext := fmt.Sprintf("Couldn't write filter file: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
return
}
tellCoreDNSToReload()
_, err = fmt.Fprintf(w, "OK %d rules\n", filter.RulesCount)
if err != nil {
errortext := fmt.Sprintf("Couldn't write body: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
}
}
func handleFilteringRemoveURL(w http.ResponseWriter, r *http.Request) {
parameters, err := parseParametersFromBody(r.Body)
if err != nil {
errortext := fmt.Sprintf("failed to parse parameters from body: %s", err)
log.Println(errortext)
http.Error(w, errortext, 400)
return
}
url, ok := parameters["url"]
if !ok {
http.Error(w, "URL parameter was not specified", 400)
return
}
if valid := govalidator.IsRequestURL(url); !valid {
http.Error(w, "URL parameter is not valid request URL", 400)
return
}
// go through each element and delete if url matches
newFilters := config.Filters[:0]
for _, filter := range config.Filters {
if filter.URL != url {
newFilters = append(newFilters, filter)
}
}
config.Filters = newFilters
err = writeAllConfigs()
if err != nil {
errortext := fmt.Sprintf("Couldn't write config file: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
return
}
err = writeFilterFile()
if err != nil {
errortext := fmt.Sprintf("Couldn't write filter file: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
return
}
tellCoreDNSToReload()
_, err = fmt.Fprintf(w, "OK\n")
if err != nil {
errortext := fmt.Sprintf("Couldn't write body: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
}
}
func handleFilteringEnableURL(w http.ResponseWriter, r *http.Request) {
parameters, err := parseParametersFromBody(r.Body)
if err != nil {
errortext := fmt.Sprintf("failed to parse parameters from body: %s", err)
log.Println(errortext)
http.Error(w, errortext, 400)
return
}
url, ok := parameters["url"]
if !ok {
http.Error(w, "URL parameter was not specified", 400)
return
}
if valid := govalidator.IsRequestURL(url); !valid {
http.Error(w, "URL parameter is not valid request URL", http.StatusBadRequest)
return
}
found := false
for i := range config.Filters {
filter := &config.Filters[i] // otherwise we will be operating on a copy
if filter.URL == url {
filter.Enabled = true
found = true
}
}
if !found {
http.Error(w, "URL parameter was not previously added", http.StatusBadRequest)
return
}
err = writeAllConfigs()
if err != nil {
errortext := fmt.Sprintf("Couldn't write config file: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
return
}
// kick off refresh of rules from new URLs
refreshFiltersIfNeccessary()
err = writeFilterFile()
if err != nil {
errortext := fmt.Sprintf("Couldn't write filter file: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
return
}
tellCoreDNSToReload()
_, err = fmt.Fprintf(w, "OK\n")
if err != nil {
errortext := fmt.Sprintf("Couldn't write body: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
}
}
func handleFilteringDisableURL(w http.ResponseWriter, r *http.Request) {
parameters, err := parseParametersFromBody(r.Body)
if err != nil {
errortext := fmt.Sprintf("failed to parse parameters from body: %s", err)
log.Println(errortext)
http.Error(w, errortext, 400)
return
}
url, ok := parameters["url"]
if !ok {
http.Error(w, "URL parameter was not specified", 400)
return
}
if valid := govalidator.IsRequestURL(url); !valid {
http.Error(w, "URL parameter is not valid request URL", http.StatusBadRequest)
return
}
found := false
for i := range config.Filters {
filter := &config.Filters[i] // otherwise we will be operating on a copy
if filter.URL == url {
filter.Enabled = false
found = true
}
}
if !found {
http.Error(w, "URL parameter was not previously added", http.StatusBadRequest)
return
}
err = writeAllConfigs()
if err != nil {
errortext := fmt.Sprintf("Couldn't write config file: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
return
}
err = writeFilterFile()
if err != nil {
errortext := fmt.Sprintf("Couldn't write filter file: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
return
}
tellCoreDNSToReload()
_, err = fmt.Fprintf(w, "OK\n")
if err != nil {
errortext := fmt.Sprintf("Couldn't write body: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
}
// TODO: regenerate coredns config and tell coredns to reload it if it's running
}
func handleFilteringSetRules(w http.ResponseWriter, r *http.Request) {
body, err := ioutil.ReadAll(r.Body)
if err != nil {
errortext := fmt.Sprintf("Failed to read request body: %s", err)
log.Println(errortext)
http.Error(w, errortext, 400)
return
}
config.UserRules = strings.Split(string(body), "\n")
err = writeAllConfigs()
if err != nil {
errortext := fmt.Sprintf("Couldn't write config file: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
return
}
err = writeFilterFile()
if err != nil {
errortext := fmt.Sprintf("Couldn't write filter file: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
return
}
tellCoreDNSToReload()
_, err = fmt.Fprintf(w, "OK\n")
if err != nil {
errortext := fmt.Sprintf("Couldn't write body: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
}
}
func handleFilteringRefresh(w http.ResponseWriter, r *http.Request) {
force := r.URL.Query().Get("force")
if force != "" {
config.Lock()
for i := range config.Filters {
filter := &config.Filters[i] // otherwise we will be operating on a copy
filter.LastUpdated = time.Unix(0, 0)
}
config.Unlock() // not defer because refreshFiltersIfNeccessary locks it too
}
updated := refreshFiltersIfNeccessary()
fmt.Fprintf(w, "OK %d filters updated\n", updated)
}
func runFilterRefreshers() {
go func() {
for range time.Tick(time.Second) {
refreshFiltersIfNeccessary()
}
}()
}
func refreshFiltersIfNeccessary() int {
now := time.Now()
config.Lock()
// deduplicate
// TODO: move it somewhere else
{
i := 0 // output index, used for deletion later
urls := map[string]bool{}
for _, filter := range config.Filters {
if _, ok := urls[filter.URL]; !ok {
// we didn't see it before, keep it
urls[filter.URL] = true // remember the URL
config.Filters[i] = filter
i++
}
}
// all entries we want to keep are at front, delete the rest
config.Filters = config.Filters[:i]
}
// fetch URLs
updateCount := 0
for i := range config.Filters {
filter := &config.Filters[i] // otherwise we will be operating on a copy
updated, err := filter.update(now)
if err != nil {
log.Printf("Failed to update filter %s: %s\n", filter.URL, err)
continue
}
if updated {
updateCount++
}
}
config.Unlock()
if updateCount > 0 {
err := writeFilterFile()
if err != nil {
errortext := fmt.Sprintf("Couldn't write filter file: %s", err)
log.Println(errortext)
}
tellCoreDNSToReload()
}
return updateCount
}
func (filter *filter) update(now time.Time) (bool, error) {
if !filter.Enabled {
return false, nil
}
elapsed := time.Since(filter.LastUpdated)
if elapsed <= updatePeriod {
return false, nil
}
// use same update period for failed filter downloads to avoid flooding with requests
filter.LastUpdated = now
resp, err := client.Get(filter.URL)
if resp != nil && resp.Body != nil {
defer resp.Body.Close()
}
if err != nil {
log.Printf("Couldn't request filter from URL %s, skipping: %s", filter.URL, err)
return false, err
}
if resp.StatusCode >= 400 {
log.Printf("Got status code %d from URL %s, skipping", resp.StatusCode, filter.URL)
return false, fmt.Errorf("Got status code >= 400: %d", resp.StatusCode)
}
body, err := ioutil.ReadAll(resp.Body)
if err != nil {
log.Printf("Couldn't fetch filter contents from URL %s, skipping: %s", filter.URL, err)
return false, err
}
// extract filter name and count number of rules
lines := strings.Split(string(body), "\n")
rulesCount := 0
seenTitle := false
d := dnsfilter.New()
for _, line := range lines {
line = strings.TrimSpace(line)
if len(line) > 0 && line[0] == '!' {
if m := filterTitle.FindAllStringSubmatch(line, -1); len(m) > 0 && len(m[0]) >= 2 && !seenTitle {
filter.Name = m[0][1]
seenTitle = true
}
} else if len(line) != 0 {
err = d.AddRule(line, 0)
if err == dnsfilter.ErrInvalidSyntax {
continue
}
if err != nil {
log.Printf("Couldn't add rule %s: %s", filter.URL, err)
return false, err
}
rulesCount++
}
}
if bytes.Equal(filter.contents, body) {
return false, nil
}
log.Printf("Filter %s updated: %d bytes, %d rules", filter.URL, len(body), rulesCount)
filter.RulesCount = rulesCount
filter.contents = body
return true, nil
}
// write filter file
func writeFilterFile() error {
filterpath := filepath.Join(config.ourBinaryDir, config.CoreDNS.FilterFile)
log.Printf("Writing filter file: %s", filterpath)
// TODO: check if file contents have modified
data := []byte{}
config.RLock()
filters := config.Filters
for _, filter := range filters {
if !filter.Enabled {
continue
}
data = append(data, filter.contents...)
data = append(data, '\n')
}
for _, rule := range config.UserRules {
data = append(data, []byte(rule)...)
data = append(data, '\n')
}
config.RUnlock()
err := ioutil.WriteFile(filterpath+".tmp", data, 0644)
if err != nil {
log.Printf("Couldn't write filter file: %s", err)
return err
}
err = os.Rename(filterpath+".tmp", filterpath)
if err != nil {
log.Printf("Couldn't rename filter file: %s", err)
return err
}
return nil
}
// ------------
// safebrowsing
// ------------
func handleSafeBrowsingEnable(w http.ResponseWriter, r *http.Request) {
config.CoreDNS.SafeBrowsingEnabled = true
err := writeAllConfigsAndReloadCoreDNS()
if err != nil {
errortext := fmt.Sprintf("Couldn't write config file: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
return
}
_, err = fmt.Fprintf(w, "OK\n")
if err != nil {
errortext := fmt.Sprintf("Couldn't write body: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
}
}
func handleSafeBrowsingDisable(w http.ResponseWriter, r *http.Request) {
config.CoreDNS.SafeBrowsingEnabled = false
err := writeAllConfigsAndReloadCoreDNS()
if err != nil {
errortext := fmt.Sprintf("Couldn't write config file: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
return
}
_, err = fmt.Fprintf(w, "OK\n")
if err != nil {
errortext := fmt.Sprintf("Couldn't write body: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
}
}
func handleSafeBrowsingStatus(w http.ResponseWriter, r *http.Request) {
data := map[string]interface{}{
"enabled": config.CoreDNS.SafeBrowsingEnabled,
}
json, err := json.Marshal(data)
if err != nil {
errortext := fmt.Sprintf("Unable to marshal status json: %s", err)
log.Println(errortext)
http.Error(w, errortext, 500)
}
w.Header().Set("Content-Type", "application/json")
_, err = w.Write(json)
if err != nil {
errortext := fmt.Sprintf("Unable to write response json: %s", err)
log.Println(errortext)
http.Error(w, errortext, 500)
return
}
}
// --------
// parental
// --------
func handleParentalEnable(w http.ResponseWriter, r *http.Request) {
parameters, err := parseParametersFromBody(r.Body)
if err != nil {
errortext := fmt.Sprintf("failed to parse parameters from body: %s", err)
log.Println(errortext)
http.Error(w, errortext, 400)
return
}
sensitivity, ok := parameters["sensitivity"]
if !ok {
http.Error(w, "URL parameter was not specified", 400)
return
}
switch sensitivity {
case "3":
break
case "EARLY_CHILDHOOD":
sensitivity = "3"
case "10":
break
case "YOUNG":
sensitivity = "10"
case "13":
break
case "TEEN":
sensitivity = "13"
case "17":
break
case "MATURE":
sensitivity = "17"
default:
http.Error(w, "Sensitivity must be set to valid value", 400)
return
}
i, err := strconv.Atoi(sensitivity)
if err != nil {
http.Error(w, "Sensitivity must be set to valid value", 400)
return
}
config.CoreDNS.ParentalSensitivity = i
config.CoreDNS.ParentalEnabled = true
err = writeAllConfigsAndReloadCoreDNS()
if err != nil {
errortext := fmt.Sprintf("Couldn't write config file: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
return
}
_, err = fmt.Fprintf(w, "OK\n")
if err != nil {
errortext := fmt.Sprintf("Couldn't write body: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
}
}
func handleParentalDisable(w http.ResponseWriter, r *http.Request) {
config.CoreDNS.ParentalEnabled = false
err := writeAllConfigsAndReloadCoreDNS()
if err != nil {
errortext := fmt.Sprintf("Couldn't write config file: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
return
}
_, err = fmt.Fprintf(w, "OK\n")
if err != nil {
errortext := fmt.Sprintf("Couldn't write body: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
}
}
func handleParentalStatus(w http.ResponseWriter, r *http.Request) {
data := map[string]interface{}{
"enabled": config.CoreDNS.ParentalEnabled,
}
if config.CoreDNS.ParentalEnabled {
data["sensitivity"] = config.CoreDNS.ParentalSensitivity
}
json, err := json.Marshal(data)
if err != nil {
errortext := fmt.Sprintf("Unable to marshal status json: %s", err)
log.Println(errortext)
http.Error(w, errortext, 500)
return
}
w.Header().Set("Content-Type", "application/json")
_, err = w.Write(json)
if err != nil {
errortext := fmt.Sprintf("Unable to write response json: %s", err)
log.Println(errortext)
http.Error(w, errortext, 500)
return
}
}
// ------------
// safebrowsing
// ------------
func handleSafeSearchEnable(w http.ResponseWriter, r *http.Request) {
config.CoreDNS.SafeSearchEnabled = true
err := writeAllConfigsAndReloadCoreDNS()
if err != nil {
errortext := fmt.Sprintf("Couldn't write config file: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
return
}
_, err = fmt.Fprintf(w, "OK\n")
if err != nil {
errortext := fmt.Sprintf("Couldn't write body: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
}
}
func handleSafeSearchDisable(w http.ResponseWriter, r *http.Request) {
config.CoreDNS.SafeSearchEnabled = false
err := writeAllConfigsAndReloadCoreDNS()
if err != nil {
errortext := fmt.Sprintf("Couldn't write config file: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
return
}
_, err = fmt.Fprintf(w, "OK\n")
if err != nil {
errortext := fmt.Sprintf("Couldn't write body: %s", err)
log.Println(errortext)
http.Error(w, errortext, http.StatusInternalServerError)
}
}
func handleSafeSearchStatus(w http.ResponseWriter, r *http.Request) {
data := map[string]interface{}{
"enabled": config.CoreDNS.SafeSearchEnabled,
}
json, err := json.Marshal(data)
if err != nil {
errortext := fmt.Sprintf("Unable to marshal status json: %s", err)
log.Println(errortext)
http.Error(w, errortext, 500)
return
}
w.Header().Set("Content-Type", "application/json")
_, err = w.Write(json)
if err != nil {
errortext := fmt.Sprintf("Unable to write response json: %s", err)
log.Println(errortext)
http.Error(w, errortext, 500)
return
}
}
func registerControlHandlers() {
http.HandleFunc("/control/start", optionalAuth(ensurePOST(handleStart)))
http.HandleFunc("/control/stop", optionalAuth(ensurePOST(handleStop)))
http.HandleFunc("/control/restart", optionalAuth(ensurePOST(handleRestart)))
http.HandleFunc("/control/status", optionalAuth(ensureGET(handleStatus)))
http.HandleFunc("/control/stats", optionalAuth(ensureGET(handleStats)))
http.HandleFunc("/control/stats_history", optionalAuth(ensureGET(handleStatsHistory)))
http.HandleFunc("/control/stats_top", optionalAuth(ensureGET(handleStatsTop)))
http.HandleFunc("/control/stats_reset", optionalAuth(ensurePOST(handleStatsReset)))
http.HandleFunc("/control/querylog", optionalAuth(ensureGET(handleQueryLog)))
http.HandleFunc("/control/querylog_enable", optionalAuth(ensurePOST(handleQueryLogEnable)))
http.HandleFunc("/control/querylog_disable", optionalAuth(ensurePOST(handleQueryLogDisable)))
http.HandleFunc("/control/set_upstream_dns", optionalAuth(ensurePOST(handleSetUpstreamDNS)))
http.HandleFunc("/control/test_upstream_dns", optionalAuth(ensurePOST(handleTestUpstreamDNS)))
http.HandleFunc("/control/version.json", optionalAuth(handleGetVersionJSON))
http.HandleFunc("/control/filtering/enable", optionalAuth(ensurePOST(handleFilteringEnable)))
http.HandleFunc("/control/filtering/disable", optionalAuth(ensurePOST(handleFilteringDisable)))
http.HandleFunc("/control/filtering/status", optionalAuth(ensureGET(handleFilteringStatus)))
http.HandleFunc("/control/filtering/add_url", optionalAuth(ensurePUT(handleFilteringAddURL)))
http.HandleFunc("/control/filtering/remove_url", optionalAuth(ensureDELETE(handleFilteringRemoveURL)))
http.HandleFunc("/control/filtering/enable_url", optionalAuth(ensurePOST(handleFilteringEnableURL)))
http.HandleFunc("/control/filtering/disable_url", optionalAuth(ensurePOST(handleFilteringDisableURL)))
http.HandleFunc("/control/filtering/set_rules", optionalAuth(ensurePUT(handleFilteringSetRules)))
http.HandleFunc("/control/filtering/refresh", optionalAuth(ensurePOST(handleFilteringRefresh)))
http.HandleFunc("/control/safebrowsing/enable", optionalAuth(ensurePOST(handleSafeBrowsingEnable)))
http.HandleFunc("/control/safebrowsing/disable", optionalAuth(ensurePOST(handleSafeBrowsingDisable)))
http.HandleFunc("/control/safebrowsing/status", optionalAuth(ensureGET(handleSafeBrowsingStatus)))
http.HandleFunc("/control/parental/enable", optionalAuth(ensurePOST(handleParentalEnable)))
http.HandleFunc("/control/parental/disable", optionalAuth(ensurePOST(handleParentalDisable)))
http.HandleFunc("/control/parental/status", optionalAuth(ensureGET(handleParentalStatus)))
http.HandleFunc("/control/safesearch/enable", optionalAuth(ensurePOST(handleSafeSearchEnable)))
http.HandleFunc("/control/safesearch/disable", optionalAuth(ensurePOST(handleSafeSearchDisable)))
http.HandleFunc("/control/safesearch/status", optionalAuth(ensureGET(handleSafeSearchStatus)))
}