storage/kubernetes: allow arbitrary client IDs

Use a hash algorithm to match client IDs to Kubernetes object names.
Because cryptographic hash algorithms produce sums larger than a
Kubernetes name can fit, a non-cryptographic hash is used instead.
Hash collisions are checked and result in errors.
This commit is contained in:
Eric Chiang 2016-10-27 15:55:23 -07:00
parent 99717cb56d
commit d7a75c5b5d
4 changed files with 115 additions and 35 deletions

View File

@ -4,10 +4,13 @@ import (
"bytes"
"crypto/tls"
"crypto/x509"
"encoding/base32"
"encoding/base64"
"encoding/json"
"errors"
"fmt"
"hash"
"hash/fnv"
"io"
"io/ioutil"
"net"
@ -31,6 +34,14 @@ type client struct {
baseURL string
namespace string
// Hash function to map IDs (which could span a large range) to Kubernetes names.
// While this is not currently upgradable, it could be in the future.
//
// The default hash is a non-cryptographic hash, because cryptographic hashes
// always produce sums too long to fit into a Kubernetes name. Because of this,
// gets, updates, and deletes are _always_ checked for collisions.
hash func() hash.Hash
// API version of the oidc resources. For example "oidc.coreos.com". This is
// currently not configurable, but could be in the future.
apiVersion string
@ -40,6 +51,18 @@ type client struct {
cancel context.CancelFunc
}
// idToName maps an arbitrary ID, such as an email or client ID to a Kubernetes object name.
func (c *client) idToName(s string) string {
return idToName(s, c.hash)
}
// Kubernetes names must match the regexp '[a-z0-9]([-a-z0-9]*[a-z0-9])?'.
var encoding = base32.NewEncoding("abcdefghijklmnopqrstuvwxyz234567")
func idToName(s string, h func() hash.Hash) string {
return strings.TrimRight(encoding.EncodeToString(h().Sum([]byte(s))), "=")
}
func (c *client) urlFor(apiVersion, namespace, resource, name string) string {
basePath := "apis/"
if apiVersion == "v1" {
@ -277,6 +300,7 @@ func newClient(cluster k8sapi.Cluster, user k8sapi.AuthInfo, namespace string) (
return &client{
client: &http.Client{Transport: t},
baseURL: cluster.Server,
hash: func() hash.Hash { return fnv.New64() },
namespace: namespace,
apiVersion: "oidc.coreos.com/v1",
}, nil

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@ -1,6 +1,33 @@
package kubernetes
import "testing"
import (
"hash"
"hash/fnv"
"sync"
"testing"
)
// This test does not have an explicit error condition but is used
// with the race detector to detect the safety of idToName.
func TestIDToName(t *testing.T) {
n := 100
var wg sync.WaitGroup
wg.Add(n)
c := make(chan struct{})
h := func() hash.Hash { return fnv.New64() }
for i := 0; i < n; i++ {
go func() {
<-c
name := idToName("foo", h)
_ = name
wg.Done()
}()
}
close(c)
wg.Wait()
}
func TestNamespaceFromServiceAccountJWT(t *testing.T) {
namespace, err := namespaceFromServiceAccountJWT(serviceAccountToken)

View File

@ -5,6 +5,7 @@ import (
"fmt"
"log"
"net/http"
"strings"
"time"
"golang.org/x/net/context"
@ -187,21 +188,47 @@ func (cli *client) GetAuthCode(id string) (storage.AuthCode, error) {
}
func (cli *client) GetClient(id string) (storage.Client, error) {
var c Client
if err := cli.get(resourceClient, id, &c); err != nil {
c, err := cli.getClient(id)
if err != nil {
return storage.Client{}, err
}
return toStorageClient(c), nil
}
func (cli *client) getClient(id string) (Client, error) {
var c Client
name := cli.idToName(id)
if err := cli.get(resourceClient, name, &c); err != nil {
return Client{}, err
}
if c.ID != id {
return Client{}, fmt.Errorf("get client: ID %q mapped to client with ID %q", id, c.ID)
}
return c, nil
}
func (cli *client) GetPassword(email string) (storage.Password, error) {
var p Password
if err := cli.get(resourcePassword, emailToID(email), &p); err != nil {
p, err := cli.getPassword(email)
if err != nil {
return storage.Password{}, err
}
return toStoragePassword(p), nil
}
func (cli *client) getPassword(email string) (Password, error) {
// TODO(ericchiang): Figure out whose job it is to lowercase emails.
email = strings.ToLower(email)
var p Password
name := cli.idToName(email)
if err := cli.get(resourcePassword, name, &p); err != nil {
return Password{}, err
}
if email != p.Email {
return Password{}, fmt.Errorf("get email: email %q mapped to password with email %q", email, p.Email)
}
return p, nil
}
func (cli *client) GetKeys() (storage.Keys, error) {
var keys Keys
if err := cli.get(resourceKeys, keysName, &keys); err != nil {
@ -242,7 +269,12 @@ func (cli *client) DeleteAuthCode(code string) error {
}
func (cli *client) DeleteClient(id string) error {
return cli.delete(resourceClient, id)
// Check for hash collition.
c, err := cli.getClient(id)
if err != nil {
return err
}
return cli.delete(resourceClient, c.ObjectMeta.Name)
}
func (cli *client) DeleteRefresh(id string) error {
@ -250,28 +282,34 @@ func (cli *client) DeleteRefresh(id string) error {
}
func (cli *client) DeletePassword(email string) error {
return cli.delete(resourcePassword, emailToID(email))
// Check for hash collition.
p, err := cli.getPassword(email)
if err != nil {
return err
}
return cli.delete(resourcePassword, p.ObjectMeta.Name)
}
func (cli *client) UpdateClient(id string, updater func(old storage.Client) (storage.Client, error)) error {
var c Client
if err := cli.get(resourceClient, id, &c); err != nil {
return err
}
updated, err := updater(toStorageClient(c))
c, err := cli.getClient(id)
if err != nil {
return err
}
updated, err := updater(toStorageClient(c))
if err != nil {
return err
}
updated.ID = c.ID
newClient := cli.fromStorageClient(updated)
newClient.ObjectMeta = c.ObjectMeta
return cli.put(resourceClient, id, newClient)
return cli.put(resourceClient, c.ObjectMeta.Name, newClient)
}
func (cli *client) UpdatePassword(email string, updater func(old storage.Password) (storage.Password, error)) error {
id := emailToID(email)
var p Password
if err := cli.get(resourcePassword, id, &p); err != nil {
p, err := cli.getPassword(email)
if err != nil {
return err
}
@ -279,10 +317,11 @@ func (cli *client) UpdatePassword(email string, updater func(old storage.Passwor
if err != nil {
return err
}
updated.Email = p.Email
newPassword := cli.fromStoragePassword(updated)
newPassword.ObjectMeta = p.ObjectMeta
return cli.put(resourcePassword, id, newPassword)
return cli.put(resourcePassword, p.ObjectMeta.Name, newPassword)
}
func (cli *client) UpdateKeys(updater func(old storage.Keys) (storage.Keys, error)) error {

View File

@ -1,7 +1,6 @@
package kubernetes
import (
"encoding/base32"
"strings"
"time"
@ -75,13 +74,14 @@ const keysName = "openid-connect-keys"
// Client is a mirrored struct from storage with JSON struct tags and
// Kubernetes type metadata.
//
// TODO(ericchiang): Kubernetes has an extremely restricted set of characters it can use for IDs.
// Consider base32ing client IDs.
type Client struct {
// Name is a hash of the ID.
k8sapi.TypeMeta `json:",inline"`
k8sapi.ObjectMeta `json:"metadata,omitempty"`
// ID is immutable, since it's a primary key and should not be changed.
ID string `json:"id,omitempty"`
Secret string `json:"secret,omitempty"`
RedirectURIs []string `json:"redirectURIs,omitempty"`
TrustedPeers []string `json:"trustedPeers,omitempty"`
@ -106,9 +106,10 @@ func (cli *client) fromStorageClient(c storage.Client) Client {
APIVersion: cli.apiVersion,
},
ObjectMeta: k8sapi.ObjectMeta{
Name: c.ID,
Name: cli.idToName(c.ID),
Namespace: cli.namespace,
},
ID: c.ID,
Secret: c.Secret,
RedirectURIs: c.RedirectURIs,
TrustedPeers: c.TrustedPeers,
@ -120,7 +121,7 @@ func (cli *client) fromStorageClient(c storage.Client) Client {
func toStorageClient(c Client) storage.Client {
return storage.Client{
ID: c.ObjectMeta.Name,
ID: c.ID,
Secret: c.Secret,
RedirectURIs: c.RedirectURIs,
TrustedPeers: c.TrustedPeers,
@ -258,17 +259,6 @@ type Password struct {
UserID string `json:"userID,omitempty"`
}
// Kubernetes only allows lower case letters for names.
//
// NOTE(ericchiang): This is currently copied from the storage package's NewID()
// method. Once we refactor those into the storage, just use that instead.
var encoding = base32.NewEncoding("abcdefghijklmnopqrstuvwxyz234567")
// Map an arbitrary email to a valid Kuberntes name.
func emailToID(email string) string {
return strings.TrimRight(encoding.EncodeToString([]byte(strings.ToLower(email))), "=")
}
func (cli *client) fromStoragePassword(p storage.Password) Password {
email := strings.ToLower(p.Email)
return Password{
@ -277,7 +267,7 @@ func (cli *client) fromStoragePassword(p storage.Password) Password {
APIVersion: cli.apiVersion,
},
ObjectMeta: k8sapi.ObjectMeta{
Name: emailToID(email),
Name: cli.idToName(email),
Namespace: cli.namespace,
},
Email: email,