Xray-core/common/matcher/geoip/conf.go
2021-03-24 23:01:20 +08:00

91 lines
1.9 KiB
Go

package geoip
import (
"runtime"
"github.com/golang/protobuf/proto"
"github.com/xtls/xray-core/common/platform/filesystem"
)
var (
FileCache = make(map[string][]byte)
IPCache = make(map[string]*GeoIP)
)
func LoadGeoIP(code string) ([]*CIDR, error) {
return LoadIPFile("geoip.dat", code)
}
func LoadIPFile(file, code string) ([]*CIDR, error) {
index := file + ":" + code
if IPCache[index] == nil {
bs, err := loadFile(file)
if err != nil {
return nil, newError("failed to load file: ", file).Base(err)
}
bs = find(bs, []byte(code))
if bs == nil {
return nil, newError("code not found in ", file, ": ", code)
}
var geoipdat GeoIP
if err := proto.Unmarshal(bs, &geoipdat); err != nil {
return nil, newError("error unmarshal IP in ", file, ": ", code).Base(err)
}
defer runtime.GC() // or debug.FreeOSMemory()
return geoipdat.Cidr, nil // do not cache geoip
IPCache[index] = &geoipdat
}
return IPCache[index].Cidr, nil
}
func loadFile(file string) ([]byte, error) {
if FileCache[file] == nil {
bs, err := filesystem.ReadAsset(file)
if err != nil {
return nil, newError("failed to open file: ", file).Base(err)
}
if len(bs) == 0 {
return nil, newError("empty file: ", file)
}
// Do not cache file, may save RAM when there
// are many files, but consume CPU each time.
return bs, nil
FileCache[file] = bs
}
return FileCache[file], nil
}
func find(data, code []byte) []byte {
codeL := len(code)
if codeL == 0 {
return nil
}
for {
dataL := len(data)
if dataL < 2 {
return nil
}
x, y := proto.DecodeVarint(data[1:])
if x == 0 && y == 0 {
return nil
}
headL, bodyL := 1+y, int(x)
dataL -= headL
if dataL < bodyL {
return nil
}
data = data[headL:]
if int(data[1]) == codeL {
for i := 0; i < codeL && data[2+i] == code[i]; i++ {
if i+1 == codeL {
return data[:bodyL]
}
}
}
if dataL == bodyL {
return nil
}
data = data[bodyL:]
}
}