blob: ba0413101ddb60a62969c435c3c9f28319cf2db1 [file] [log] [blame]
// Copyright 2016 The etcd Authors
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package auth
// CAUTION: This randum number based token mechanism is only for testing purpose.
// JWT based mechanism will be added in the near future.
import (
"context"
"crypto/rand"
"fmt"
"math/big"
"strconv"
"strings"
"sync"
"time"
)
const (
letters = "abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ"
defaultSimpleTokenLength = 16
)
// var for testing purposes
var (
simpleTokenTTLDefault = 300 * time.Second
simpleTokenTTLResolution = 1 * time.Second
)
type simpleTokenTTLKeeper struct {
tokens map[string]time.Time
donec chan struct{}
stopc chan struct{}
deleteTokenFunc func(string)
mu *sync.Mutex
simpleTokenTTL time.Duration
}
func (tm *simpleTokenTTLKeeper) stop() {
select {
case tm.stopc <- struct{}{}:
case <-tm.donec:
}
<-tm.donec
}
func (tm *simpleTokenTTLKeeper) addSimpleToken(token string) {
tm.tokens[token] = time.Now().Add(tm.simpleTokenTTL)
}
func (tm *simpleTokenTTLKeeper) resetSimpleToken(token string) {
if _, ok := tm.tokens[token]; ok {
tm.tokens[token] = time.Now().Add(tm.simpleTokenTTL)
}
}
func (tm *simpleTokenTTLKeeper) deleteSimpleToken(token string) {
delete(tm.tokens, token)
}
func (tm *simpleTokenTTLKeeper) run() {
tokenTicker := time.NewTicker(simpleTokenTTLResolution)
defer func() {
tokenTicker.Stop()
close(tm.donec)
}()
for {
select {
case <-tokenTicker.C:
nowtime := time.Now()
tm.mu.Lock()
for t, tokenendtime := range tm.tokens {
if nowtime.After(tokenendtime) {
tm.deleteTokenFunc(t)
delete(tm.tokens, t)
}
}
tm.mu.Unlock()
case <-tm.stopc:
return
}
}
}
type tokenSimple struct {
indexWaiter func(uint64) <-chan struct{}
simpleTokenKeeper *simpleTokenTTLKeeper
simpleTokensMu sync.Mutex
simpleTokens map[string]string // token -> username
simpleTokenTTL time.Duration
}
func (t *tokenSimple) genTokenPrefix() (string, error) {
ret := make([]byte, defaultSimpleTokenLength)
for i := 0; i < defaultSimpleTokenLength; i++ {
bInt, err := rand.Int(rand.Reader, big.NewInt(int64(len(letters))))
if err != nil {
return "", err
}
ret[i] = letters[bInt.Int64()]
}
return string(ret), nil
}
func (t *tokenSimple) assignSimpleTokenToUser(username, token string) {
t.simpleTokensMu.Lock()
defer t.simpleTokensMu.Unlock()
if t.simpleTokenKeeper == nil {
return
}
_, ok := t.simpleTokens[token]
if ok {
plog.Panicf("token %s is alredy used", token)
}
t.simpleTokens[token] = username
t.simpleTokenKeeper.addSimpleToken(token)
}
func (t *tokenSimple) invalidateUser(username string) {
if t.simpleTokenKeeper == nil {
return
}
t.simpleTokensMu.Lock()
for token, name := range t.simpleTokens {
if strings.Compare(name, username) == 0 {
delete(t.simpleTokens, token)
t.simpleTokenKeeper.deleteSimpleToken(token)
}
}
t.simpleTokensMu.Unlock()
}
func (t *tokenSimple) enable() {
if t.simpleTokenTTL <= 0 {
t.simpleTokenTTL = simpleTokenTTLDefault
}
delf := func(tk string) {
if username, ok := t.simpleTokens[tk]; ok {
plog.Infof("deleting token %s for user %s", tk, username)
delete(t.simpleTokens, tk)
}
}
t.simpleTokenKeeper = &simpleTokenTTLKeeper{
tokens: make(map[string]time.Time),
donec: make(chan struct{}),
stopc: make(chan struct{}),
deleteTokenFunc: delf,
mu: &t.simpleTokensMu,
simpleTokenTTL: t.simpleTokenTTL,
}
go t.simpleTokenKeeper.run()
}
func (t *tokenSimple) disable() {
t.simpleTokensMu.Lock()
tk := t.simpleTokenKeeper
t.simpleTokenKeeper = nil
t.simpleTokens = make(map[string]string) // invalidate all tokens
t.simpleTokensMu.Unlock()
if tk != nil {
tk.stop()
}
}
func (t *tokenSimple) info(ctx context.Context, token string, revision uint64) (*AuthInfo, bool) {
if !t.isValidSimpleToken(ctx, token) {
return nil, false
}
t.simpleTokensMu.Lock()
username, ok := t.simpleTokens[token]
if ok && t.simpleTokenKeeper != nil {
t.simpleTokenKeeper.resetSimpleToken(token)
}
t.simpleTokensMu.Unlock()
return &AuthInfo{Username: username, Revision: revision}, ok
}
func (t *tokenSimple) assign(ctx context.Context, username string, rev uint64) (string, error) {
// rev isn't used in simple token, it is only used in JWT
index := ctx.Value(AuthenticateParamIndex{}).(uint64)
simpleTokenPrefix := ctx.Value(AuthenticateParamSimpleTokenPrefix{}).(string)
token := fmt.Sprintf("%s.%d", simpleTokenPrefix, index)
t.assignSimpleTokenToUser(username, token)
return token, nil
}
func (t *tokenSimple) isValidSimpleToken(ctx context.Context, token string) bool {
splitted := strings.Split(token, ".")
if len(splitted) != 2 {
return false
}
index, err := strconv.Atoi(splitted[1])
if err != nil {
return false
}
select {
case <-t.indexWaiter(uint64(index)):
return true
case <-ctx.Done():
}
return false
}
func newTokenProviderSimple(indexWaiter func(uint64) <-chan struct{}, TokenTTL time.Duration) *tokenSimple {
return &tokenSimple{
simpleTokens: make(map[string]string),
indexWaiter: indexWaiter,
simpleTokenTTL: TokenTTL,
}
}