AdGuardHome/querylog/decode.go

179 lines
3.3 KiB
Go

package querylog
import (
"encoding/base64"
"strconv"
"strings"
"time"
"github.com/AdguardTeam/AdGuardHome/dnsfilter"
"github.com/AdguardTeam/golibs/log"
"github.com/miekg/dns"
)
// decodeLogEntry - decodes query log entry from a line
// nolint (gocyclo)
func decodeLogEntry(ent *logEntry, str string) {
var b bool
var i int
var err error
for {
k, v, t := readJSON(&str)
if t == jsonTErr {
break
}
switch k {
case "IP":
if len(ent.IP) == 0 {
ent.IP = v
}
case "T":
ent.Time, err = time.Parse(time.RFC3339, v)
case "QH":
ent.QHost = v
case "QT":
ent.QType = v
case "QC":
ent.QClass = v
case "CP":
ent.ClientProto = v
case "Answer":
ent.Answer, err = base64.StdEncoding.DecodeString(v)
case "OrigAnswer":
ent.OrigAnswer, err = base64.StdEncoding.DecodeString(v)
case "IsFiltered":
b, err = strconv.ParseBool(v)
ent.Result.IsFiltered = b
case "Rule":
ent.Result.Rule = v
case "FilterID":
i, err = strconv.Atoi(v)
ent.Result.FilterID = int64(i)
case "Reason":
i, err = strconv.Atoi(v)
ent.Result.Reason = dnsfilter.Reason(i)
case "Upstream":
ent.Upstream = v
case "Elapsed":
i, err = strconv.Atoi(v)
ent.Elapsed = time.Duration(i)
// pre-v0.99.3 compatibility:
case "Question":
var qstr []byte
qstr, err = base64.StdEncoding.DecodeString(v)
if err != nil {
break
}
q := new(dns.Msg)
err = q.Unpack(qstr)
if err != nil {
break
}
ent.QHost = q.Question[0].Name
if len(ent.QHost) == 0 {
break
}
ent.QHost = ent.QHost[:len(ent.QHost)-1]
ent.QType = dns.TypeToString[q.Question[0].Qtype]
ent.QClass = dns.ClassToString[q.Question[0].Qclass]
case "Time":
ent.Time, err = time.Parse(time.RFC3339, v)
}
if err != nil {
log.Debug("decodeLogEntry err: %s", err)
break
}
}
}
// Get value from "key":"value"
func readJSONValue(s, name string) string {
i := strings.Index(s, "\""+name+"\":\"")
if i == -1 {
return ""
}
start := i + 1 + len(name) + 3
i = strings.IndexByte(s[start:], '"')
if i == -1 {
return ""
}
end := start + i
return s[start:end]
}
const (
jsonTErr = iota
jsonTObj
jsonTStr
jsonTNum
jsonTBool
)
// Parse JSON key-value pair
// e.g.: "key":VALUE where VALUE is "string", true|false (boolean), or 123.456 (number)
// Note the limitations:
// . doesn't support whitespace
// . doesn't support "null"
// . doesn't validate boolean or number
// . no proper handling of {} braces
// . no handling of [] brackets
// Return (key, value, type)
func readJSON(ps *string) (string, string, int32) {
s := *ps
k := ""
v := ""
t := int32(jsonTErr)
q1 := strings.IndexByte(s, '"')
if q1 == -1 {
return k, v, t
}
q2 := strings.IndexByte(s[q1+1:], '"')
if q2 == -1 {
return k, v, t
}
k = s[q1+1 : q1+1+q2]
s = s[q1+1+q2+1:]
if len(s) < 2 || s[0] != ':' {
return k, v, t
}
if s[1] == '"' {
q2 = strings.IndexByte(s[2:], '"')
if q2 == -1 {
return k, v, t
}
v = s[2 : 2+q2]
t = jsonTStr
s = s[2+q2+1:]
} else if s[1] == '{' {
t = jsonTObj
s = s[1+1:]
} else {
sep := strings.IndexAny(s[1:], ",}")
if sep == -1 {
return k, v, t
}
v = s[1 : 1+sep]
if s[1] == 't' || s[1] == 'f' {
t = jsonTBool
} else if s[1] == '.' || (s[1] >= '0' && s[1] <= '9') {
t = jsonTNum
}
s = s[1+sep+1:]
}
*ps = s
return k, v, t
}