Files
zitadel/internal/command/command.go
T
Marco A.andLivio Spring b6f7808691 fix: use protected http client for outgoing connections
# Which Problems Are Solved

Backchannel logout, notification webhooks and SAML metadata URL fetches are vulnerable to SSRF attacks: the attacker can set any URL as backchannel logout URL, potentially pointing to resources on the server running Zitadel.
Additionally existing denylist usage was vulnerable against DNS rebinding, redirect and HTTPs downgrades and missed some common default entries.

# How the Problems Are Solved

 - Added an HTTPClient configuration to allow initiating a single HTTP client using one denylist, timeout, redirect and downgrade settings. The client is passed into every component requiring an outgoing http connection (apart from ServicePing and Sonyflake machine id resolver).
 - Added a `NewHTTPTransport` function returning an http.Roundtripper to check the denylist using `Control`, which is called before `Dial` to prevent DNS rebinding attacks / TOCTOC gaps.
 - The HTTP Client also uses an `io.LimitReader` wrapper with a configurable `MaxBodySize` to prevent OOM issues or even DOS attacks by components reading the whole body without limit.
  - Implement a dynamic denylist: it is now possible to define as many denylists as needed. You just need to define a denylist target and assign it to your denylist.
  - Propagate the usage of global denylists to all places making use of existing deny lists.
  - Block creation of OIDC apps if selected backchannel logout URL is in the denylist
  - Block workers using backchannel logout URLs that are in the denylist.
  - Implement the same concept for webhooks (email and sms)
  - Implement the same concept for SAML metadata URL fetches

# Additional Context

- Closes https://github.com/zitadel/zitadel/security/advisories/GHSA-29jh-8cfq-rr8x

---------

Co-authored-by: Livio Spring <9405495+livio-a@users.noreply.github.com>

(cherry picked from commit 8e82ec1cb9)
2026-06-15 16:08:00 +02:00

395 lines
14 KiB
Go

package command
import (
"context"
"crypto/rand"
"crypto/x509"
"crypto/x509/pkix"
"encoding/pem"
"fmt"
"math/big"
"net"
"net/http"
"slices"
"strconv"
"strings"
"sync"
"time"
"github.com/go-jose/go-jose/v4"
"github.com/zitadel/logging"
"github.com/zitadel/zitadel/internal/api/authz"
api_http "github.com/zitadel/zitadel/internal/api/http"
"github.com/zitadel/zitadel/internal/cache/connector"
"github.com/zitadel/zitadel/internal/command/preparation"
sd "github.com/zitadel/zitadel/internal/config/systemdefaults"
"github.com/zitadel/zitadel/internal/crypto"
"github.com/zitadel/zitadel/internal/denylist"
"github.com/zitadel/zitadel/internal/domain"
"github.com/zitadel/zitadel/internal/eventstore"
"github.com/zitadel/zitadel/internal/id"
internal_net "github.com/zitadel/zitadel/internal/net"
"github.com/zitadel/zitadel/internal/notification/senders"
"github.com/zitadel/zitadel/internal/static"
"github.com/zitadel/zitadel/internal/telemetry/tracing"
webauthn_helper "github.com/zitadel/zitadel/internal/webauthn"
"github.com/zitadel/zitadel/internal/zerrors"
)
type Commands struct {
httpClient *http.Client
jobs sync.WaitGroup
checkPermission domain.PermissionCheck
newEncryptedCode encrypedCodeFunc
newEncryptedCodeWithDefault encryptedCodeWithDefaultFunc
newHashedSecret hashedSecretFunc
eventstore *eventstore.Eventstore
static static.Storage
idGenerator id.Generator
zitadelRoles []authz.RoleMapping
externalDomain string
externalSecure bool
externalPort uint16
idpConfigEncryption crypto.EncryptionAlgorithm
smtpEncryption crypto.EncryptionAlgorithm
smsEncryption crypto.EncryptionAlgorithm
userEncryption crypto.EncryptionAlgorithm
targetEncryption crypto.EncryptionAlgorithm
userPasswordHasher *crypto.Hasher
secretHasher *crypto.Hasher
machineKeySize int
applicationKeySize int
domainVerificationAlg crypto.EncryptionAlgorithm
domainVerificationGenerator crypto.Generator
domainVerificationValidator func(domain, token, verifier string, checkType api_http.CheckType) error
sessionTokenCreator func(sessionID string) (id string, token string, err error)
sessionTokenVerifier func(ctx context.Context, sessionToken, sessionID, tokenID string) (err error)
defaultAccessTokenLifetime time.Duration
defaultRefreshTokenLifetime time.Duration
defaultRefreshTokenIdleLifetime time.Duration
phoneCodeVerifier func(ctx context.Context, id string) (senders.CodeGenerator, error)
tarpit func(failedAttempts uint64)
multifactors domain.MultifactorConfigs
webauthnConfig *webauthn_helper.Config
keySize int
keyAlgorithm crypto.EncryptionAlgorithm
authAlgorithm crypto.AuthAlgorithm
certificateAlgorithm crypto.EncryptionAlgorithm
certKeySize int
privateKeyLifetime time.Duration
publicKeyLifetime time.Duration
certificateLifetime time.Duration
defaultSecretGenerators *SecretGenerators
maxIdPIntentLifetime time.Duration
samlCertificateAndKeyGenerator func(id string) ([]byte, []byte, error)
webKeyGenerator func(keyID string, alg crypto.EncryptionAlgorithm, genConfig crypto.WebKeyConfig) (encryptedPrivate *crypto.CryptoValue, public *jose.JSONWebKey, err error)
GrpcMethodExisting func(method string) bool
GrpcServiceExisting func(method string) bool
ActionFunctionExisting func(function string) bool
EventExisting func(event string) bool
EventGroupExisting func(group string) bool
GenerateDomain func(instanceName, domain string) (string, error)
caches *Caches
// Store instance IDs where all milestones are reached (except InstanceDeleted).
// These instance's milestones never need to be invalidated,
// so the query and cache overhead can be completely eliminated.
milestonesCompleted sync.Map
loginPaths LoginPaths
ipLookupFunction internal_net.IPLookupFunc
denyList []denylist.AddressChecker
}
//go:generate mockgen -package command -destination ./mock_login_paths.go . LoginPaths
type LoginPaths interface {
DefaultEmailCodeURLTemplate(ctx context.Context) string
DefaultPasswordSetURLTemplate(ctx context.Context) string
DefaultPasskeySetURLTemplate(ctx context.Context) string
DefaultDomainClaimedURLTemplate(ctx context.Context) string
}
func StartCommands(
ctx context.Context,
es *eventstore.Eventstore,
cacheConnectors connector.Connectors,
defaults sd.SystemDefaults,
zitadelRoles []authz.RoleMapping,
staticStore static.Storage,
webAuthN *webauthn_helper.Config,
externalDomain string,
externalSecure bool,
externalPort uint16,
idpConfigEncryption, otpEncryption, smtpEncryption, smsEncryption, userEncryption, domainVerificationEncryption, samlEncryption, targetEncryption crypto.EncryptionAlgorithm,
oidcEncryption crypto.AuthEncryptionAlgorithm,
httpClient *http.Client,
permissionCheck domain.PermissionCheck,
sessionTokenVerifier func(ctx context.Context, sessionToken string, sessionID string, tokenID string) (err error),
defaultAccessTokenLifetime, defaultRefreshTokenLifetime, defaultRefreshTokenIdleLifetime time.Duration,
defaultSecretGenerators *SecretGenerators,
loginPaths LoginPaths,
denyList []denylist.AddressChecker,
) (repo *Commands, err error) {
if externalDomain == "" {
return nil, zerrors.ThrowInvalidArgument(nil, "COMMAND-Df21s", "no external domain specified")
}
idGenerator := id.SonyFlakeGenerator()
// reuse the oidcEncryption to be able to handle both tokens in the interceptor later on
sessionAlg := oidcEncryption
secretHasher, err := defaults.SecretHasher.NewHasher()
if err != nil {
return nil, fmt.Errorf("secret hasher: %w", err)
}
userPasswordHasher, err := defaults.PasswordHasher.NewHasher()
if err != nil {
return nil, fmt.Errorf("password hasher: %w", err)
}
caches, err := startCaches(ctx, cacheConnectors)
if err != nil {
return nil, fmt.Errorf("caches: %w", err)
}
ipLookupFunction := net.LookupIP
repo = &Commands{
eventstore: es,
static: staticStore,
idGenerator: idGenerator,
zitadelRoles: zitadelRoles,
externalDomain: externalDomain,
externalSecure: externalSecure,
externalPort: externalPort,
keySize: defaults.KeyConfig.Size,
certKeySize: defaults.KeyConfig.CertificateSize,
privateKeyLifetime: defaults.KeyConfig.PrivateKeyLifetime,
publicKeyLifetime: defaults.KeyConfig.PublicKeyLifetime,
certificateLifetime: defaults.KeyConfig.CertificateLifetime,
maxIdPIntentLifetime: defaults.MaxIdPIntentLifetime,
idpConfigEncryption: idpConfigEncryption,
smtpEncryption: smtpEncryption,
smsEncryption: smsEncryption,
userEncryption: userEncryption,
targetEncryption: targetEncryption,
userPasswordHasher: userPasswordHasher,
secretHasher: secretHasher,
machineKeySize: int(defaults.SecretGenerators.MachineKeySize),
applicationKeySize: int(defaults.SecretGenerators.ApplicationKeySize),
domainVerificationAlg: domainVerificationEncryption,
domainVerificationGenerator: crypto.NewEncryptionGenerator(defaults.DomainVerification.VerificationGenerator, domainVerificationEncryption),
domainVerificationValidator: api_http.ValidateDomain,
keyAlgorithm: oidcEncryption,
authAlgorithm: oidcEncryption,
certificateAlgorithm: samlEncryption,
webauthnConfig: webAuthN,
httpClient: httpClient,
checkPermission: permissionCheck,
newEncryptedCode: newEncryptedCode,
newEncryptedCodeWithDefault: newEncryptedCodeWithDefaultConfig,
sessionTokenCreator: sessionTokenCreator(idGenerator, sessionAlg),
sessionTokenVerifier: sessionTokenVerifier,
defaultAccessTokenLifetime: defaultAccessTokenLifetime,
defaultRefreshTokenLifetime: defaultRefreshTokenLifetime,
defaultRefreshTokenIdleLifetime: defaultRefreshTokenIdleLifetime,
defaultSecretGenerators: defaultSecretGenerators,
samlCertificateAndKeyGenerator: samlCertificateAndKeyGenerator(defaults.KeyConfig.CertificateSize, defaults.KeyConfig.CertificateLifetime),
webKeyGenerator: crypto.GenerateEncryptedWebKey,
EventExisting: func(value string) bool {
return slices.Contains(es.EventTypes(), value)
},
EventGroupExisting: func(group string) bool {
return slices.ContainsFunc(es.EventTypes(), func(value string) bool {
return strings.HasPrefix(value, group)
},
)
},
GrpcServiceExisting: func(service string) bool { return false },
GrpcMethodExisting: func(method string) bool { return false },
ActionFunctionExisting: domain.ActionFunctionExists(),
multifactors: domain.MultifactorConfigs{
OTP: domain.OTPConfig{
CryptoMFA: otpEncryption,
Issuer: defaults.Multifactors.OTP.Issuer,
},
RecoveryCodes: domain.RecoveryCodesConfig{
MaxCount: defaults.Multifactors.RecoveryCodes.MaxCount,
Format: domain.RecoveryCodeFormat(defaults.Multifactors.RecoveryCodes.Format),
Length: defaults.Multifactors.RecoveryCodes.Length,
WithHyphen: defaults.Multifactors.RecoveryCodes.WithHyphen,
},
},
GenerateDomain: domain.NewGeneratedInstanceDomain,
caches: caches,
loginPaths: loginPaths,
ipLookupFunction: ipLookupFunction,
denyList: denyList,
}
if defaultSecretGenerators != nil && defaultSecretGenerators.ClientSecret != nil {
repo.newHashedSecret = newHashedSecretWithDefault(secretHasher, defaultSecretGenerators.ClientSecret)
}
repo.phoneCodeVerifier = repo.phoneCodeVerifierFromConfig
repo.tarpit = defaults.Tarpit.Tarpit()
return repo, nil
}
type AppendReducer interface {
AppendEvents(...eventstore.Event)
// TODO: Why is it allowed to return an error here?
Reduce() error
}
func (c *Commands) pushAppendAndReduce(ctx context.Context, object AppendReducer, cmds ...eventstore.Command) error {
if len(cmds) == 0 {
return nil
}
events, err := c.eventstore.Push(ctx, cmds...)
if err != nil {
return err
}
return AppendAndReduce(object, events...)
}
type AppendReducerDetails interface {
AppendEvents(...eventstore.Event)
// TODO: Why is it allowed to return an error here?
Reduce() error
GetWriteModel() *eventstore.WriteModel
}
func (c *Commands) pushAppendAndReduceDetails(ctx context.Context, object AppendReducerDetails, cmds ...eventstore.Command) (*domain.ObjectDetails, error) {
if err := c.pushAppendAndReduce(ctx, object, cmds...); err != nil {
return nil, err
}
return writeModelToObjectDetails(object.GetWriteModel()), nil
}
func AppendAndReduce(object AppendReducer, events ...eventstore.Event) error {
object.AppendEvents(events...)
return object.Reduce()
}
func queryAndReduce(ctx context.Context, filter preparation.FilterToQueryReducer, wm eventstore.QueryReducer) error {
events, err := filter(ctx, wm.Query())
if err != nil {
return err
}
if len(events) == 0 {
return nil
}
wm.AppendEvents(events...)
return wm.Reduce()
}
type existsWriteModel interface {
Exists() bool
eventstore.QueryReducer
}
func exists(ctx context.Context, filter preparation.FilterToQueryReducer, wm existsWriteModel) (bool, error) {
err := queryAndReduce(ctx, filter, wm)
if err != nil {
return false, err
}
return wm.Exists(), nil
}
func samlCertificateAndKeyGenerator(keySize int, lifetime time.Duration) func(id string) ([]byte, []byte, error) {
return func(id string) ([]byte, []byte, error) {
priv, pub, err := crypto.GenerateKeyPair(keySize)
if err != nil {
return nil, nil, err
}
serial, err := strconv.Atoi(id)
if err != nil {
return nil, nil, err
}
now := time.Now()
template := x509.Certificate{
SerialNumber: big.NewInt(int64(serial)),
Subject: pkix.Name{
Organization: []string{"ZITADEL"},
CommonName: fmt.Sprintf("ZITADEL SP %s", id),
SerialNumber: id,
},
Issuer: pkix.Name{
Organization: []string{"ZITADEL"},
CommonName: "ZITADEL",
},
NotBefore: now,
NotAfter: now.Add(lifetime),
KeyUsage: x509.KeyUsageKeyEncipherment | x509.KeyUsageDigitalSignature,
ExtKeyUsage: []x509.ExtKeyUsage{x509.ExtKeyUsageServerAuth},
BasicConstraintsValid: true,
}
derBytes, err := x509.CreateCertificate(rand.Reader, &template, &template, pub, priv)
if err != nil {
return nil, nil, zerrors.ThrowInternalf(err, "COMMAND-x92u101j", "failed to create certificate")
}
keyBlock := &pem.Block{Type: "RSA PRIVATE KEY", Bytes: x509.MarshalPKCS1PrivateKey(priv)}
certBlock := &pem.Block{Type: "CERTIFICATE", Bytes: derBytes}
return pem.EncodeToMemory(keyBlock), pem.EncodeToMemory(certBlock), nil
}
}
// Close blocks until all async jobs are finished,
// the context expires or after eventstore.PushTimeout.
func (c *Commands) Close(ctx context.Context) error {
if c.eventstore.PushTimeout != 0 {
var cancel context.CancelFunc
ctx, cancel = context.WithTimeout(ctx, c.eventstore.PushTimeout)
defer cancel()
}
done := make(chan struct{})
go func() {
c.jobs.Wait()
close(done)
}()
select {
case <-done:
return nil
case <-ctx.Done():
return ctx.Err()
}
}
// asyncPush attempts to push events to the eventstore in a separate Go routine.
// This can be used to speed up request times when the outcome of the push is
// not important for business logic but have a pure logging function.
// For example this can be used for Secret Check Success and Failed events.
// On push error, a log line describing the error will be emitted.
func (c *Commands) asyncPush(ctx context.Context, cmds ...eventstore.Command) {
// Create a new context, as the request scoped context might get
// canceled before we where able to push.
// The eventstore has its own PushTimeout setting,
// so we don't need to have a context with timeout here.
ctx = context.WithoutCancel(ctx)
c.jobs.Add(1)
go func() {
defer c.jobs.Done()
localCtx, span := tracing.NewSpan(ctx)
_, err := c.eventstore.Push(localCtx, cmds...)
if err != nil {
for _, cmd := range cmds {
logging.WithError(err).Warnf("could not push event %q", cmd.Type())
}
}
span.EndWithError(err)
}()
}