402 lines
11 KiB
Go
402 lines
11 KiB
Go
package auth
|
|
|
|
import (
|
|
"context"
|
|
"encoding/json"
|
|
"errors"
|
|
"math/rand"
|
|
"net/http"
|
|
"time"
|
|
|
|
"github.com/armon/go-metrics"
|
|
"github.com/hashicorp/go-hclog"
|
|
"github.com/hashicorp/vault/api"
|
|
"github.com/hashicorp/vault/sdk/helper/jsonutil"
|
|
)
|
|
|
|
const (
|
|
defaultMinBackoff = 1 * time.Second
|
|
defaultMaxBackoff = 5 * time.Minute
|
|
)
|
|
|
|
// AuthMethod is the interface that auto-auth methods implement for the agent
|
|
// to use.
|
|
type AuthMethod interface {
|
|
// Authenticate returns a mount path, header, request body, and error.
|
|
// The header may be nil if no special header is needed.
|
|
Authenticate(context.Context, *api.Client) (string, http.Header, map[string]interface{}, error)
|
|
NewCreds() chan struct{}
|
|
CredSuccess()
|
|
Shutdown()
|
|
}
|
|
|
|
// AuthMethodWithClient is an extended interface that can return an API client
|
|
// for use during the authentication call.
|
|
type AuthMethodWithClient interface {
|
|
AuthMethod
|
|
AuthClient(client *api.Client) (*api.Client, error)
|
|
}
|
|
|
|
type AuthConfig struct {
|
|
Logger hclog.Logger
|
|
MountPath string
|
|
WrapTTL time.Duration
|
|
Config map[string]interface{}
|
|
}
|
|
|
|
// AuthHandler is responsible for keeping a token alive and renewed and passing
|
|
// new tokens to the sink server
|
|
type AuthHandler struct {
|
|
OutputCh chan string
|
|
TemplateTokenCh chan string
|
|
token string
|
|
logger hclog.Logger
|
|
client *api.Client
|
|
random *rand.Rand
|
|
wrapTTL time.Duration
|
|
maxBackoff time.Duration
|
|
minBackoff time.Duration
|
|
enableReauthOnNewCredentials bool
|
|
enableTemplateTokenCh bool
|
|
}
|
|
|
|
type AuthHandlerConfig struct {
|
|
Logger hclog.Logger
|
|
Client *api.Client
|
|
WrapTTL time.Duration
|
|
MaxBackoff time.Duration
|
|
MinBackoff time.Duration
|
|
Token string
|
|
EnableReauthOnNewCredentials bool
|
|
EnableTemplateTokenCh bool
|
|
}
|
|
|
|
func NewAuthHandler(conf *AuthHandlerConfig) *AuthHandler {
|
|
ah := &AuthHandler{
|
|
// This is buffered so that if we try to output after the sink server
|
|
// has been shut down, during agent shutdown, we won't block
|
|
OutputCh: make(chan string, 1),
|
|
TemplateTokenCh: make(chan string, 1),
|
|
token: conf.Token,
|
|
logger: conf.Logger,
|
|
client: conf.Client,
|
|
random: rand.New(rand.NewSource(int64(time.Now().Nanosecond()))),
|
|
wrapTTL: conf.WrapTTL,
|
|
minBackoff: conf.MinBackoff,
|
|
maxBackoff: conf.MaxBackoff,
|
|
enableReauthOnNewCredentials: conf.EnableReauthOnNewCredentials,
|
|
enableTemplateTokenCh: conf.EnableTemplateTokenCh,
|
|
}
|
|
|
|
return ah
|
|
}
|
|
|
|
func backoffOrQuit(ctx context.Context, backoff *agentBackoff) {
|
|
select {
|
|
case <-time.After(backoff.current):
|
|
case <-ctx.Done():
|
|
}
|
|
|
|
// Increase exponential backoff for the next time if we don't
|
|
// successfully auth/renew/etc.
|
|
backoff.next()
|
|
}
|
|
|
|
func (ah *AuthHandler) Run(ctx context.Context, am AuthMethod) error {
|
|
if am == nil {
|
|
return errors.New("auth handler: nil auth method")
|
|
}
|
|
|
|
if ah.minBackoff <= 0 {
|
|
ah.minBackoff = defaultMinBackoff
|
|
}
|
|
|
|
backoff := newAgentBackoff(ah.minBackoff, ah.maxBackoff)
|
|
|
|
if backoff.min >= backoff.max {
|
|
return errors.New("auth handler: min_backoff cannot be greater than max_backoff")
|
|
}
|
|
|
|
ah.logger.Info("starting auth handler")
|
|
defer func() {
|
|
am.Shutdown()
|
|
close(ah.OutputCh)
|
|
close(ah.TemplateTokenCh)
|
|
ah.logger.Info("auth handler stopped")
|
|
}()
|
|
|
|
credCh := am.NewCreds()
|
|
if !ah.enableReauthOnNewCredentials {
|
|
realCredCh := credCh
|
|
credCh = nil
|
|
if realCredCh != nil {
|
|
go func() {
|
|
for {
|
|
select {
|
|
case <-ctx.Done():
|
|
return
|
|
case <-realCredCh:
|
|
}
|
|
}
|
|
}()
|
|
}
|
|
}
|
|
if credCh == nil {
|
|
credCh = make(chan struct{})
|
|
}
|
|
|
|
var watcher *api.LifetimeWatcher
|
|
first := true
|
|
|
|
for {
|
|
select {
|
|
case <-ctx.Done():
|
|
return nil
|
|
|
|
default:
|
|
}
|
|
|
|
var clientToUse *api.Client
|
|
var err error
|
|
var path string
|
|
var data map[string]interface{}
|
|
var header http.Header
|
|
|
|
switch am.(type) {
|
|
case AuthMethodWithClient:
|
|
clientToUse, err = am.(AuthMethodWithClient).AuthClient(ah.client)
|
|
if err != nil {
|
|
ah.logger.Error("error creating client for authentication call", "error", err, "backoff", backoff)
|
|
backoffOrQuit(ctx, backoff)
|
|
metrics.IncrCounter([]string{"agent", "auth", "failure"}, 1)
|
|
continue
|
|
}
|
|
default:
|
|
clientToUse = ah.client
|
|
}
|
|
|
|
// Disable retry on the client to ensure our backoffOrQuit function is
|
|
// the only source of retry/backoff.
|
|
clientToUse.SetMaxRetries(0)
|
|
|
|
var secret *api.Secret = new(api.Secret)
|
|
if first && ah.token != "" {
|
|
ah.logger.Debug("using preloaded token")
|
|
|
|
first = false
|
|
ah.logger.Debug("lookup-self with preloaded token")
|
|
clientToUse.SetToken(ah.token)
|
|
|
|
secret, err = clientToUse.Auth().Token().LookupSelfWithContext(ctx)
|
|
if err != nil {
|
|
ah.logger.Error("could not look up token", "err", err, "backoff", backoff)
|
|
backoffOrQuit(ctx, backoff)
|
|
metrics.IncrCounter([]string{"agent", "auth", "failure"}, 1)
|
|
continue
|
|
}
|
|
|
|
duration, _ := secret.Data["ttl"].(json.Number).Int64()
|
|
secret.Auth = &api.SecretAuth{
|
|
ClientToken: secret.Data["id"].(string),
|
|
LeaseDuration: int(duration),
|
|
Renewable: secret.Data["renewable"].(bool),
|
|
}
|
|
} else {
|
|
ah.logger.Info("authenticating")
|
|
|
|
path, header, data, err = am.Authenticate(ctx, ah.client)
|
|
if err != nil {
|
|
ah.logger.Error("error getting path or data from method", "error", err, "backoff", backoff)
|
|
backoffOrQuit(ctx, backoff)
|
|
metrics.IncrCounter([]string{"agent", "auth", "failure"}, 1)
|
|
continue
|
|
}
|
|
}
|
|
|
|
if ah.wrapTTL > 0 {
|
|
wrapClient, err := clientToUse.Clone()
|
|
if err != nil {
|
|
ah.logger.Error("error creating client for wrapped call", "error", err, "backoff", backoff)
|
|
backoffOrQuit(ctx, backoff)
|
|
metrics.IncrCounter([]string{"agent", "auth", "failure"}, 1)
|
|
continue
|
|
}
|
|
wrapClient.SetWrappingLookupFunc(func(string, string) string {
|
|
return ah.wrapTTL.String()
|
|
})
|
|
clientToUse = wrapClient
|
|
}
|
|
for key, values := range header {
|
|
for _, value := range values {
|
|
clientToUse.AddHeader(key, value)
|
|
}
|
|
}
|
|
|
|
// This should only happen if there's no preloaded token (regular auto-auth login)
|
|
// or if a preloaded token has expired and is now switching to auto-auth.
|
|
if secret.Auth == nil {
|
|
secret, err = clientToUse.Logical().WriteWithContext(ctx, path, data)
|
|
// Check errors/sanity
|
|
if err != nil {
|
|
ah.logger.Error("error authenticating", "error", err, "backoff", backoff)
|
|
backoffOrQuit(ctx, backoff)
|
|
metrics.IncrCounter([]string{"agent", "auth", "failure"}, 1)
|
|
continue
|
|
}
|
|
}
|
|
|
|
switch {
|
|
case ah.wrapTTL > 0:
|
|
if secret.WrapInfo == nil {
|
|
ah.logger.Error("authentication returned nil wrap info", "backoff", backoff)
|
|
backoffOrQuit(ctx, backoff)
|
|
metrics.IncrCounter([]string{"agent", "auth", "failure"}, 1)
|
|
continue
|
|
}
|
|
if secret.WrapInfo.Token == "" {
|
|
ah.logger.Error("authentication returned empty wrapped client token", "backoff", backoff)
|
|
backoffOrQuit(ctx, backoff)
|
|
metrics.IncrCounter([]string{"agent", "auth", "failure"}, 1)
|
|
continue
|
|
}
|
|
wrappedResp, err := jsonutil.EncodeJSON(secret.WrapInfo)
|
|
if err != nil {
|
|
ah.logger.Error("failed to encode wrapinfo", "error", err, "backoff", backoff)
|
|
backoffOrQuit(ctx, backoff)
|
|
metrics.IncrCounter([]string{"agent", "auth", "failure"}, 1)
|
|
continue
|
|
}
|
|
ah.logger.Info("authentication successful, sending wrapped token to sinks and pausing")
|
|
ah.OutputCh <- string(wrappedResp)
|
|
if ah.enableTemplateTokenCh {
|
|
ah.TemplateTokenCh <- string(wrappedResp)
|
|
}
|
|
|
|
am.CredSuccess()
|
|
backoff.reset()
|
|
|
|
select {
|
|
case <-ctx.Done():
|
|
ah.logger.Info("shutdown triggered")
|
|
continue
|
|
|
|
case <-credCh:
|
|
ah.logger.Info("auth method found new credentials, re-authenticating")
|
|
continue
|
|
}
|
|
|
|
default:
|
|
if secret == nil || secret.Auth == nil {
|
|
ah.logger.Error("authentication returned nil auth info", "backoff", backoff)
|
|
backoffOrQuit(ctx, backoff)
|
|
metrics.IncrCounter([]string{"agent", "auth", "failure"}, 1)
|
|
continue
|
|
}
|
|
if secret.Auth.ClientToken == "" {
|
|
ah.logger.Error("authentication returned empty client token", "backoff", backoff)
|
|
backoffOrQuit(ctx, backoff)
|
|
metrics.IncrCounter([]string{"agent", "auth", "failure"}, 1)
|
|
continue
|
|
}
|
|
ah.logger.Info("authentication successful, sending token to sinks")
|
|
ah.OutputCh <- secret.Auth.ClientToken
|
|
if ah.enableTemplateTokenCh {
|
|
ah.TemplateTokenCh <- secret.Auth.ClientToken
|
|
}
|
|
|
|
am.CredSuccess()
|
|
backoff.reset()
|
|
}
|
|
|
|
if watcher != nil {
|
|
watcher.Stop()
|
|
}
|
|
|
|
watcher, err = clientToUse.NewLifetimeWatcher(&api.LifetimeWatcherInput{
|
|
Secret: secret,
|
|
})
|
|
if err != nil {
|
|
ah.logger.Error("error creating lifetime watcher, backing off and retrying", "error", err, "backoff", backoff)
|
|
backoffOrQuit(ctx, backoff)
|
|
metrics.IncrCounter([]string{"agent", "auth", "failure"}, 1)
|
|
continue
|
|
}
|
|
|
|
// Start the renewal process
|
|
ah.logger.Info("starting renewal process")
|
|
metrics.IncrCounter([]string{"agent", "auth", "success"}, 1)
|
|
go watcher.Renew()
|
|
|
|
LifetimeWatcherLoop:
|
|
for {
|
|
select {
|
|
case <-ctx.Done():
|
|
ah.logger.Info("shutdown triggered, stopping lifetime watcher")
|
|
watcher.Stop()
|
|
break LifetimeWatcherLoop
|
|
|
|
case err := <-watcher.DoneCh():
|
|
ah.logger.Info("lifetime watcher done channel triggered")
|
|
if err != nil {
|
|
metrics.IncrCounter([]string{"agent", "auth", "failure"}, 1)
|
|
ah.logger.Error("error renewing token", "error", err)
|
|
}
|
|
break LifetimeWatcherLoop
|
|
|
|
case <-watcher.RenewCh():
|
|
metrics.IncrCounter([]string{"agent", "auth", "success"}, 1)
|
|
ah.logger.Info("renewed auth token")
|
|
|
|
case <-credCh:
|
|
ah.logger.Info("auth method found new credentials, re-authenticating")
|
|
break LifetimeWatcherLoop
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// agentBackoff tracks exponential backoff state.
|
|
type agentBackoff struct {
|
|
min time.Duration
|
|
max time.Duration
|
|
current time.Duration
|
|
}
|
|
|
|
func newAgentBackoff(min, max time.Duration) *agentBackoff {
|
|
if max <= 0 {
|
|
max = defaultMaxBackoff
|
|
}
|
|
|
|
if min <= 0 {
|
|
min = defaultMinBackoff
|
|
}
|
|
|
|
return &agentBackoff{
|
|
current: min,
|
|
max: max,
|
|
min: min,
|
|
}
|
|
}
|
|
|
|
// next determines the next backoff duration that is roughly twice
|
|
// the current value, capped to a max value, with a measure of randomness.
|
|
func (b *agentBackoff) next() {
|
|
maxBackoff := 2 * b.current
|
|
|
|
if maxBackoff > b.max {
|
|
maxBackoff = b.max
|
|
}
|
|
|
|
// Trim a random amount (0-25%) off the doubled duration
|
|
trim := rand.Int63n(int64(maxBackoff) / 4)
|
|
b.current = maxBackoff - time.Duration(trim)
|
|
}
|
|
|
|
func (b *agentBackoff) reset() {
|
|
b.current = b.min
|
|
}
|
|
|
|
func (b agentBackoff) String() string {
|
|
return b.current.Truncate(10 * time.Millisecond).String()
|
|
}
|