traefik/pkg/middlewares/ipwhitelist/ip_whitelist.go
2019-07-10 09:26:04 +02:00

85 lines
2.2 KiB
Go

package ipwhitelist
import (
"context"
"errors"
"fmt"
"net/http"
"github.com/containous/traefik/pkg/config/dynamic"
"github.com/containous/traefik/pkg/ip"
"github.com/containous/traefik/pkg/middlewares"
"github.com/containous/traefik/pkg/tracing"
"github.com/opentracing/opentracing-go/ext"
"github.com/sirupsen/logrus"
)
const (
typeName = "IPWhiteLister"
)
// ipWhiteLister is a middleware that provides Checks of the Requesting IP against a set of Whitelists
type ipWhiteLister struct {
next http.Handler
whiteLister *ip.Checker
strategy ip.Strategy
name string
}
// New builds a new IPWhiteLister given a list of CIDR-Strings to whitelist
func New(ctx context.Context, next http.Handler, config dynamic.IPWhiteList, name string) (http.Handler, error) {
logger := middlewares.GetLogger(ctx, name, typeName)
logger.Debug("Creating middleware")
if len(config.SourceRange) == 0 {
return nil, errors.New("sourceRange is empty, IPWhiteLister not created")
}
checker, err := ip.NewChecker(config.SourceRange)
if err != nil {
return nil, fmt.Errorf("cannot parse CIDR whitelist %s: %v", config.SourceRange, err)
}
strategy, err := config.IPStrategy.Get()
if err != nil {
return nil, err
}
logger.Debugf("Setting up IPWhiteLister with sourceRange: %s", config.SourceRange)
return &ipWhiteLister{
strategy: strategy,
whiteLister: checker,
next: next,
name: name,
}, nil
}
func (wl *ipWhiteLister) GetTracingInformation() (string, ext.SpanKindEnum) {
return wl.name, tracing.SpanKindNoneEnum
}
func (wl *ipWhiteLister) ServeHTTP(rw http.ResponseWriter, req *http.Request) {
logger := middlewares.GetLogger(req.Context(), wl.name, typeName)
err := wl.whiteLister.IsAuthorized(wl.strategy.GetIP(req))
if err != nil {
logMessage := fmt.Sprintf("rejecting request %+v: %v", req, err)
logger.Debug(logMessage)
tracing.SetErrorWithEvent(req, logMessage)
reject(logger, rw)
return
}
logger.Debugf("Accept %s: %+v", wl.strategy.GetIP(req), req)
wl.next.ServeHTTP(rw, req)
}
func reject(logger logrus.FieldLogger, rw http.ResponseWriter) {
statusCode := http.StatusForbidden
rw.WriteHeader(statusCode)
_, err := rw.Write([]byte(http.StatusText(statusCode)))
if err != nil {
logger.Error(err)
}
}