AdGuardHome/internal/dnsfilter/safesearch.go
Eugene Burkov 5a50efadb2 Pull request: 2509 type-safety vol.1
Merge in DNS/adguard-home from 2509-type-safety to master

Updates #2509.

Squashed commit of the following:

commit 535968eb7de3a9e0817ddb57bc2320e5c5a55086
Author: Eugene Burkov <e.burkov@adguard.com>
Date:   Wed Jan 20 15:06:16 2021 +0300

    dhcpd: fix comments

commit dc79b80381fe7a8ecec6f9659fd23710c9229f59
Author: Eugene Burkov <e.burkov@adguard.com>
Date:   Wed Jan 20 14:08:10 2021 +0300

    all: improve docs

commit 156ebf6c9bad95f82cd121f019f3b59b77b18ba6
Author: Eugene Burkov <e.burkov@adguard.com>
Date:   Tue Jan 19 17:08:15 2021 +0300

    all: improve JSON encoding and decoding
2021-01-20 15:59:24 +03:00

364 lines
14 KiB
Go

package dnsfilter
import (
"bytes"
"encoding/binary"
"encoding/gob"
"encoding/json"
"fmt"
"net"
"net/http"
"time"
"github.com/AdguardTeam/golibs/cache"
"github.com/AdguardTeam/golibs/log"
)
/*
expire byte[4]
res Result
*/
func (d *DNSFilter) setCacheResult(cache cache.Cache, host string, res Result) int {
var buf bytes.Buffer
expire := uint(time.Now().Unix()) + d.Config.CacheTime*60
exp := make([]byte, 4)
binary.BigEndian.PutUint32(exp, uint32(expire))
_, _ = buf.Write(exp)
enc := gob.NewEncoder(&buf)
err := enc.Encode(res)
if err != nil {
log.Error("gob.Encode(): %s", err)
return 0
}
val := buf.Bytes()
_ = cache.Set([]byte(host), val)
return len(val)
}
func getCachedResult(cache cache.Cache, host string) (Result, bool) {
data := cache.Get([]byte(host))
if data == nil {
return Result{}, false
}
exp := int(binary.BigEndian.Uint32(data[:4]))
if exp <= int(time.Now().Unix()) {
cache.Del([]byte(host))
return Result{}, false
}
var buf bytes.Buffer
buf.Write(data[4:])
dec := gob.NewDecoder(&buf)
r := Result{}
err := dec.Decode(&r)
if err != nil {
log.Debug("gob.Decode(): %s", err)
return Result{}, false
}
return r, true
}
// SafeSearchDomain returns replacement address for search engine
func (d *DNSFilter) SafeSearchDomain(host string) (string, bool) {
val, ok := safeSearchDomains[host]
return val, ok
}
func (d *DNSFilter) checkSafeSearch(host string) (Result, error) {
if log.GetLevel() >= log.DEBUG {
timer := log.StartTimer()
defer timer.LogElapsed("SafeSearch: lookup for %s", host)
}
// Check cache. Return cached result if it was found
cachedValue, isFound := getCachedResult(gctx.safeSearchCache, host)
if isFound {
// atomic.AddUint64(&gctx.stats.Safesearch.CacheHits, 1)
log.Tracef("SafeSearch: found in cache: %s", host)
return cachedValue, nil
}
safeHost, ok := d.SafeSearchDomain(host)
if !ok {
return Result{}, nil
}
res := Result{
IsFiltered: true,
Reason: FilteredSafeSearch,
Rules: []*ResultRule{{}},
}
if ip := net.ParseIP(safeHost); ip != nil {
res.Rules[0].IP = ip
valLen := d.setCacheResult(gctx.safeSearchCache, host, res)
log.Debug("SafeSearch: stored in cache: %s (%d bytes)", host, valLen)
return res, nil
}
// TODO this address should be resolved with upstream that was configured in dnsforward
ips, err := net.LookupIP(safeHost)
if err != nil {
log.Tracef("SafeSearchDomain for %s was found but failed to lookup for %s cause %s", host, safeHost, err)
return Result{}, err
}
for _, ip := range ips {
if ipv4 := ip.To4(); ipv4 != nil {
res.Rules[0].IP = ipv4
l := d.setCacheResult(gctx.safeSearchCache, host, res)
log.Debug("SafeSearch: stored in cache: %s (%d bytes)", host, l)
return res, nil
}
}
return Result{}, fmt.Errorf("no ipv4 addresses in safe search response for %s", safeHost)
}
func (d *DNSFilter) handleSafeSearchEnable(w http.ResponseWriter, r *http.Request) {
d.Config.SafeSearchEnabled = true
d.Config.ConfigModified()
}
func (d *DNSFilter) handleSafeSearchDisable(w http.ResponseWriter, r *http.Request) {
d.Config.SafeSearchEnabled = false
d.Config.ConfigModified()
}
func (d *DNSFilter) handleSafeSearchStatus(w http.ResponseWriter, r *http.Request) {
w.Header().Set("Content-Type", "application/json")
err := json.NewEncoder(w).Encode(&struct {
Enabled bool `json:"enabled"`
}{
Enabled: d.Config.SafeSearchEnabled,
})
if err != nil {
httpError(r, w, http.StatusInternalServerError, "Unable to write response json: %s", err)
return
}
}
var safeSearchDomains = map[string]string{
"yandex.com": "213.180.193.56",
"yandex.ru": "213.180.193.56",
"yandex.ua": "213.180.193.56",
"yandex.by": "213.180.193.56",
"yandex.kz": "213.180.193.56",
"www.yandex.com": "213.180.193.56",
"www.yandex.ru": "213.180.193.56",
"www.yandex.ua": "213.180.193.56",
"www.yandex.by": "213.180.193.56",
"www.yandex.kz": "213.180.193.56",
"www.bing.com": "strict.bing.com",
"duckduckgo.com": "safe.duckduckgo.com",
"www.duckduckgo.com": "safe.duckduckgo.com",
"start.duckduckgo.com": "safe.duckduckgo.com",
"www.google.com": "forcesafesearch.google.com",
"www.google.ad": "forcesafesearch.google.com",
"www.google.ae": "forcesafesearch.google.com",
"www.google.com.af": "forcesafesearch.google.com",
"www.google.com.ag": "forcesafesearch.google.com",
"www.google.com.ai": "forcesafesearch.google.com",
"www.google.al": "forcesafesearch.google.com",
"www.google.am": "forcesafesearch.google.com",
"www.google.co.ao": "forcesafesearch.google.com",
"www.google.com.ar": "forcesafesearch.google.com",
"www.google.as": "forcesafesearch.google.com",
"www.google.at": "forcesafesearch.google.com",
"www.google.com.au": "forcesafesearch.google.com",
"www.google.az": "forcesafesearch.google.com",
"www.google.ba": "forcesafesearch.google.com",
"www.google.com.bd": "forcesafesearch.google.com",
"www.google.be": "forcesafesearch.google.com",
"www.google.bf": "forcesafesearch.google.com",
"www.google.bg": "forcesafesearch.google.com",
"www.google.com.bh": "forcesafesearch.google.com",
"www.google.bi": "forcesafesearch.google.com",
"www.google.bj": "forcesafesearch.google.com",
"www.google.com.bn": "forcesafesearch.google.com",
"www.google.com.bo": "forcesafesearch.google.com",
"www.google.com.br": "forcesafesearch.google.com",
"www.google.bs": "forcesafesearch.google.com",
"www.google.bt": "forcesafesearch.google.com",
"www.google.co.bw": "forcesafesearch.google.com",
"www.google.by": "forcesafesearch.google.com",
"www.google.com.bz": "forcesafesearch.google.com",
"www.google.ca": "forcesafesearch.google.com",
"www.google.cd": "forcesafesearch.google.com",
"www.google.cf": "forcesafesearch.google.com",
"www.google.cg": "forcesafesearch.google.com",
"www.google.ch": "forcesafesearch.google.com",
"www.google.ci": "forcesafesearch.google.com",
"www.google.co.ck": "forcesafesearch.google.com",
"www.google.cl": "forcesafesearch.google.com",
"www.google.cm": "forcesafesearch.google.com",
"www.google.cn": "forcesafesearch.google.com",
"www.google.com.co": "forcesafesearch.google.com",
"www.google.co.cr": "forcesafesearch.google.com",
"www.google.com.cu": "forcesafesearch.google.com",
"www.google.cv": "forcesafesearch.google.com",
"www.google.com.cy": "forcesafesearch.google.com",
"www.google.cz": "forcesafesearch.google.com",
"www.google.de": "forcesafesearch.google.com",
"www.google.dj": "forcesafesearch.google.com",
"www.google.dk": "forcesafesearch.google.com",
"www.google.dm": "forcesafesearch.google.com",
"www.google.com.do": "forcesafesearch.google.com",
"www.google.dz": "forcesafesearch.google.com",
"www.google.com.ec": "forcesafesearch.google.com",
"www.google.ee": "forcesafesearch.google.com",
"www.google.com.eg": "forcesafesearch.google.com",
"www.google.es": "forcesafesearch.google.com",
"www.google.com.et": "forcesafesearch.google.com",
"www.google.fi": "forcesafesearch.google.com",
"www.google.com.fj": "forcesafesearch.google.com",
"www.google.fm": "forcesafesearch.google.com",
"www.google.fr": "forcesafesearch.google.com",
"www.google.ga": "forcesafesearch.google.com",
"www.google.ge": "forcesafesearch.google.com",
"www.google.gg": "forcesafesearch.google.com",
"www.google.com.gh": "forcesafesearch.google.com",
"www.google.com.gi": "forcesafesearch.google.com",
"www.google.gl": "forcesafesearch.google.com",
"www.google.gm": "forcesafesearch.google.com",
"www.google.gp": "forcesafesearch.google.com",
"www.google.gr": "forcesafesearch.google.com",
"www.google.com.gt": "forcesafesearch.google.com",
"www.google.gy": "forcesafesearch.google.com",
"www.google.com.hk": "forcesafesearch.google.com",
"www.google.hn": "forcesafesearch.google.com",
"www.google.hr": "forcesafesearch.google.com",
"www.google.ht": "forcesafesearch.google.com",
"www.google.hu": "forcesafesearch.google.com",
"www.google.co.id": "forcesafesearch.google.com",
"www.google.ie": "forcesafesearch.google.com",
"www.google.co.il": "forcesafesearch.google.com",
"www.google.im": "forcesafesearch.google.com",
"www.google.co.in": "forcesafesearch.google.com",
"www.google.iq": "forcesafesearch.google.com",
"www.google.is": "forcesafesearch.google.com",
"www.google.it": "forcesafesearch.google.com",
"www.google.je": "forcesafesearch.google.com",
"www.google.com.jm": "forcesafesearch.google.com",
"www.google.jo": "forcesafesearch.google.com",
"www.google.co.jp": "forcesafesearch.google.com",
"www.google.co.ke": "forcesafesearch.google.com",
"www.google.com.kh": "forcesafesearch.google.com",
"www.google.ki": "forcesafesearch.google.com",
"www.google.kg": "forcesafesearch.google.com",
"www.google.co.kr": "forcesafesearch.google.com",
"www.google.com.kw": "forcesafesearch.google.com",
"www.google.kz": "forcesafesearch.google.com",
"www.google.la": "forcesafesearch.google.com",
"www.google.com.lb": "forcesafesearch.google.com",
"www.google.li": "forcesafesearch.google.com",
"www.google.lk": "forcesafesearch.google.com",
"www.google.co.ls": "forcesafesearch.google.com",
"www.google.lt": "forcesafesearch.google.com",
"www.google.lu": "forcesafesearch.google.com",
"www.google.lv": "forcesafesearch.google.com",
"www.google.com.ly": "forcesafesearch.google.com",
"www.google.co.ma": "forcesafesearch.google.com",
"www.google.md": "forcesafesearch.google.com",
"www.google.me": "forcesafesearch.google.com",
"www.google.mg": "forcesafesearch.google.com",
"www.google.mk": "forcesafesearch.google.com",
"www.google.ml": "forcesafesearch.google.com",
"www.google.com.mm": "forcesafesearch.google.com",
"www.google.mn": "forcesafesearch.google.com",
"www.google.ms": "forcesafesearch.google.com",
"www.google.com.mt": "forcesafesearch.google.com",
"www.google.mu": "forcesafesearch.google.com",
"www.google.mv": "forcesafesearch.google.com",
"www.google.mw": "forcesafesearch.google.com",
"www.google.com.mx": "forcesafesearch.google.com",
"www.google.com.my": "forcesafesearch.google.com",
"www.google.co.mz": "forcesafesearch.google.com",
"www.google.com.na": "forcesafesearch.google.com",
"www.google.com.nf": "forcesafesearch.google.com",
"www.google.com.ng": "forcesafesearch.google.com",
"www.google.com.ni": "forcesafesearch.google.com",
"www.google.ne": "forcesafesearch.google.com",
"www.google.nl": "forcesafesearch.google.com",
"www.google.no": "forcesafesearch.google.com",
"www.google.com.np": "forcesafesearch.google.com",
"www.google.nr": "forcesafesearch.google.com",
"www.google.nu": "forcesafesearch.google.com",
"www.google.co.nz": "forcesafesearch.google.com",
"www.google.com.om": "forcesafesearch.google.com",
"www.google.com.pa": "forcesafesearch.google.com",
"www.google.com.pe": "forcesafesearch.google.com",
"www.google.com.pg": "forcesafesearch.google.com",
"www.google.com.ph": "forcesafesearch.google.com",
"www.google.com.pk": "forcesafesearch.google.com",
"www.google.pl": "forcesafesearch.google.com",
"www.google.pn": "forcesafesearch.google.com",
"www.google.com.pr": "forcesafesearch.google.com",
"www.google.ps": "forcesafesearch.google.com",
"www.google.pt": "forcesafesearch.google.com",
"www.google.com.py": "forcesafesearch.google.com",
"www.google.com.qa": "forcesafesearch.google.com",
"www.google.ro": "forcesafesearch.google.com",
"www.google.ru": "forcesafesearch.google.com",
"www.google.rw": "forcesafesearch.google.com",
"www.google.com.sa": "forcesafesearch.google.com",
"www.google.com.sb": "forcesafesearch.google.com",
"www.google.sc": "forcesafesearch.google.com",
"www.google.se": "forcesafesearch.google.com",
"www.google.com.sg": "forcesafesearch.google.com",
"www.google.sh": "forcesafesearch.google.com",
"www.google.si": "forcesafesearch.google.com",
"www.google.sk": "forcesafesearch.google.com",
"www.google.com.sl": "forcesafesearch.google.com",
"www.google.sn": "forcesafesearch.google.com",
"www.google.so": "forcesafesearch.google.com",
"www.google.sm": "forcesafesearch.google.com",
"www.google.sr": "forcesafesearch.google.com",
"www.google.st": "forcesafesearch.google.com",
"www.google.com.sv": "forcesafesearch.google.com",
"www.google.td": "forcesafesearch.google.com",
"www.google.tg": "forcesafesearch.google.com",
"www.google.co.th": "forcesafesearch.google.com",
"www.google.com.tj": "forcesafesearch.google.com",
"www.google.tk": "forcesafesearch.google.com",
"www.google.tl": "forcesafesearch.google.com",
"www.google.tm": "forcesafesearch.google.com",
"www.google.tn": "forcesafesearch.google.com",
"www.google.to": "forcesafesearch.google.com",
"www.google.com.tr": "forcesafesearch.google.com",
"www.google.tt": "forcesafesearch.google.com",
"www.google.com.tw": "forcesafesearch.google.com",
"www.google.co.tz": "forcesafesearch.google.com",
"www.google.com.ua": "forcesafesearch.google.com",
"www.google.co.ug": "forcesafesearch.google.com",
"www.google.co.uk": "forcesafesearch.google.com",
"www.google.com.uy": "forcesafesearch.google.com",
"www.google.co.uz": "forcesafesearch.google.com",
"www.google.com.vc": "forcesafesearch.google.com",
"www.google.co.ve": "forcesafesearch.google.com",
"www.google.vg": "forcesafesearch.google.com",
"www.google.co.vi": "forcesafesearch.google.com",
"www.google.com.vn": "forcesafesearch.google.com",
"www.google.vu": "forcesafesearch.google.com",
"www.google.ws": "forcesafesearch.google.com",
"www.google.rs": "forcesafesearch.google.com",
"www.youtube.com": "restrictmoderate.youtube.com",
"m.youtube.com": "restrictmoderate.youtube.com",
"youtubei.googleapis.com": "restrictmoderate.youtube.com",
"youtube.googleapis.com": "restrictmoderate.youtube.com",
"www.youtube-nocookie.com": "restrictmoderate.youtube.com",
"pixabay.com": "safesearch.pixabay.com",
}