AdGuardHome/internal/querylog/qlog.go

217 lines
4.7 KiB
Go

// Package querylog provides query log functions and interfaces.
package querylog
import (
"errors"
"fmt"
"net"
"os"
"strings"
"sync"
"time"
"github.com/AdguardTeam/AdGuardHome/internal/dnsfilter"
"github.com/AdguardTeam/golibs/log"
"github.com/miekg/dns"
)
const (
queryLogFileName = "querylog.json" // .gz added during compression
)
// queryLog is a structure that writes and reads the DNS query log
type queryLog struct {
findClient func(ids []string) (c *Client, err error)
conf *Config
lock sync.Mutex
logFile string // path to the log file
// bufferLock protects buffer.
bufferLock sync.RWMutex
// buffer contains recent log entries.
buffer []*logEntry
fileFlushLock sync.Mutex // synchronize a file-flushing goroutine and main thread
flushPending bool // don't start another goroutine while the previous one is still running
fileWriteLock sync.Mutex
}
// ClientProto values are names of the client protocols.
type ClientProto string
// Client protocol names.
const (
ClientProtoDOH ClientProto = "doh"
ClientProtoDOQ ClientProto = "doq"
ClientProtoDOT ClientProto = "dot"
ClientProtoDNSCrypt ClientProto = "dnscrypt"
ClientProtoPlain ClientProto = ""
)
// NewClientProto validates that the client protocol name is valid and returns
// the name as a ClientProto.
func NewClientProto(s string) (cp ClientProto, err error) {
switch cp = ClientProto(s); cp {
case
ClientProtoDOH,
ClientProtoDOQ,
ClientProtoDOT,
ClientProtoDNSCrypt,
ClientProtoPlain:
return cp, nil
default:
return "", fmt.Errorf("invalid client proto: %q", s)
}
}
// logEntry - represents a single log entry
type logEntry struct {
// client is the found client information, if any.
client *Client
IP net.IP `json:"IP"` // Client IP
Time time.Time `json:"T"`
QHost string `json:"QH"`
QType string `json:"QT"`
QClass string `json:"QC"`
ClientID string `json:"CID,omitempty"`
ClientProto ClientProto `json:"CP"`
Answer []byte `json:",omitempty"` // sometimes empty answers happen like binerdunt.top or rev2.globalrootservers.net
OrigAnswer []byte `json:",omitempty"`
Result dnsfilter.Result
Elapsed time.Duration
Upstream string `json:",omitempty"` // if empty, means it was cached
}
func (l *queryLog) Start() {
if l.conf.HTTPRegister != nil {
l.initWeb()
}
go l.periodicRotate()
}
func (l *queryLog) Close() {
_ = l.flushLogBuffer(true)
}
func checkInterval(days uint32) bool {
return days == 1 || days == 7 || days == 30 || days == 90
}
func (l *queryLog) WriteDiskConfig(c *Config) {
*c = *l.conf
}
// Clear memory buffer and remove log files
func (l *queryLog) clear() {
l.fileFlushLock.Lock()
defer l.fileFlushLock.Unlock()
l.bufferLock.Lock()
l.buffer = nil
l.flushPending = false
l.bufferLock.Unlock()
oldLogFile := l.logFile + ".1"
err := os.Remove(oldLogFile)
if err != nil && !errors.Is(err, os.ErrNotExist) {
log.Error("removing old log file %q: %s", oldLogFile, err)
}
err = os.Remove(l.logFile)
if err != nil && !errors.Is(err, os.ErrNotExist) {
log.Error("removing log file %q: %s", l.logFile, err)
}
log.Debug("Query log: cleared")
}
func (l *queryLog) Add(params AddParams) {
var err error
if !l.conf.Enabled {
return
}
err = params.validate()
if err != nil {
log.Error("querylog: adding record: %s, skipping", err)
return
}
if params.Result == nil {
params.Result = &dnsfilter.Result{}
}
now := time.Now()
entry := logEntry{
IP: l.getClientIP(params.ClientIP),
Time: now,
Result: *params.Result,
Elapsed: params.Elapsed,
Upstream: params.Upstream,
ClientID: params.ClientID,
ClientProto: params.ClientProto,
}
q := params.Question.Question[0]
entry.QHost = strings.ToLower(q.Name[:len(q.Name)-1]) // remove the last dot
entry.QType = dns.Type(q.Qtype).String()
entry.QClass = dns.Class(q.Qclass).String()
if params.Answer != nil {
var a []byte
a, err = params.Answer.Pack()
if err != nil {
log.Error("querylog: Answer.Pack(): %s", err)
return
}
entry.Answer = a
}
if params.OrigAnswer != nil {
var a []byte
a, err = params.OrigAnswer.Pack()
if err != nil {
log.Error("querylog: OrigAnswer.Pack(): %s", err)
return
}
entry.OrigAnswer = a
}
l.bufferLock.Lock()
l.buffer = append(l.buffer, &entry)
needFlush := false
if !l.conf.FileEnabled {
if len(l.buffer) > int(l.conf.MemSize) {
// writing to file is disabled - just remove the oldest entry from array
l.buffer = l.buffer[1:]
}
} else if !l.flushPending {
needFlush = len(l.buffer) >= int(l.conf.MemSize)
if needFlush {
l.flushPending = true
}
}
l.bufferLock.Unlock()
// if buffer needs to be flushed to disk, do it now
if needFlush {
go func() {
_ = l.flushLogBuffer(false)
}()
}
}