teleport/lib/services/session.go
Andrew Lytvynov cd2f4fceb7
Remove JSON schema validation (#6685)
* Remove JSON schema validation

Removing JSON schema validation from all resource unmarshalers.

--- what JSON schema gets us

Looking at the JSON schema spec and our usage, here are the supposed benefits:
- type validation - make sure incoming data uses the right types for the right fields
- required fields - make sure that mandatory fields are set
- defaulting - set defaults for fields
- documentation - schema definition for our API objects

Note that it does _not_ do:
- fail on unknown fields in data
- fail on a required field with an empty value

--- what replaces it

Based on the above, it may seem like JSON schema provides value.
But it's not the case, let's break it down one by one:
- type validation - unmarshaling JSON into a typed Go struct does this
- required fields - only checks that the field was provided, doesn't actually check that a value is set (e.g. `"name": ""` will pass the `required` check)
  - so it's pretty useless for any real validation
  - and we already have a separate place for proper validation - `CheckAndSetDefaults` methods
- defaulting - done in `CheckAndSetDefaults` methods
  - `Version` is the only annoying field, had to add it in a bunch of objects
- documentation - protobuf definitions are the source of truth for our API schema

--- the benefits

- performance - schema validation does a few rounds of `json.Marshal/Unmarshal` in addition to actual validation; now we simply skip all that
- maintenance - no need to keep protobuf and JSON schema definitions in sync anymore
- creating new API objects - one error-prone step removed
- (future) fewer dependencies - we can _almost_ remove the Go libraries for schema validation (one transient dependency keeping them around)

* Remove services.SkipValidation

No more JSON schema validation so this option is a noop.
2021-06-01 15:27:20 -07:00

146 lines
4 KiB
Go

/*
Copyright 2021 Gravitational, Inc.
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 services
import (
"encoding/json"
"github.com/gravitational/teleport/api/types"
"github.com/gravitational/teleport/lib/utils"
"github.com/gravitational/trace"
)
// UnmarshalWebSession unmarshals the WebSession resource from JSON.
func UnmarshalWebSession(bytes []byte, opts ...MarshalOption) (types.WebSession, error) {
cfg, err := CollectOptions(opts)
if err != nil {
return nil, trace.Wrap(err)
}
var h ResourceHeader
err = json.Unmarshal(bytes, &h)
if err != nil {
return nil, trace.Wrap(err)
}
switch h.Version {
case V2:
var ws types.WebSessionV2
if err := utils.FastUnmarshal(bytes, &ws); err != nil {
return nil, trace.Wrap(err)
}
utils.UTC(&ws.Spec.BearerTokenExpires)
utils.UTC(&ws.Spec.Expires)
if err := ws.CheckAndSetDefaults(); err != nil {
return nil, trace.Wrap(err)
}
if cfg.ID != 0 {
ws.SetResourceID(cfg.ID)
}
if !cfg.Expires.IsZero() {
ws.SetExpiry(cfg.Expires)
}
return &ws, nil
}
return nil, trace.BadParameter("web session resource version %v is not supported", h.Version)
}
// MarshalWebSession marshals the WebSession resource to JSON.
func MarshalWebSession(webSession types.WebSession, opts ...MarshalOption) ([]byte, error) {
cfg, err := CollectOptions(opts)
if err != nil {
return nil, trace.Wrap(err)
}
switch webSession := webSession.(type) {
case *WebSessionV2:
if version := webSession.GetVersion(); version != V2 {
return nil, trace.BadParameter("mismatched web session version %v and type %T", version, webSession)
}
if !cfg.PreserveResourceID {
// avoid modifying the original object
// to prevent unexpected data races
copy := *webSession
copy.SetResourceID(0)
webSession = &copy
}
return utils.FastMarshal(webSession)
default:
return nil, trace.BadParameter("unrecognized web session version %T", webSession)
}
}
// MarshalWebToken serializes the web token as JSON-encoded payload
func MarshalWebToken(webToken types.WebToken, opts ...MarshalOption) ([]byte, error) {
cfg, err := CollectOptions(opts)
if err != nil {
return nil, trace.Wrap(err)
}
switch webToken := webToken.(type) {
case *types.WebTokenV3:
if version := webToken.GetVersion(); version != V3 {
return nil, trace.BadParameter("mismatched web token version %v and type %T", version, webToken)
}
if !cfg.PreserveResourceID {
// avoid modifying the original object
// to prevent unexpected data races
copy := *webToken
copy.SetResourceID(0)
webToken = &copy
}
return utils.FastMarshal(webToken)
default:
return nil, trace.BadParameter("unrecognized web token version %T", webToken)
}
}
// UnmarshalWebToken interprets bytes as JSON-encoded web token value
func UnmarshalWebToken(bytes []byte, opts ...MarshalOption) (types.WebToken, error) {
config, err := CollectOptions(opts)
if err != nil {
return nil, trace.Wrap(err)
}
var hdr ResourceHeader
err = json.Unmarshal(bytes, &hdr)
if err != nil {
return nil, trace.Wrap(err)
}
switch hdr.Version {
case V3:
var token types.WebTokenV3
if err := utils.FastUnmarshal(bytes, &token); err != nil {
return nil, trace.BadParameter("invalid web token: %v", err.Error())
}
if err := token.CheckAndSetDefaults(); err != nil {
return nil, trace.Wrap(err)
}
if config.ID != 0 {
token.SetResourceID(config.ID)
}
if !config.Expires.IsZero() {
token.Metadata.SetExpiry(config.Expires)
}
utils.UTC(token.Metadata.Expires)
return &token, nil
}
return nil, trace.BadParameter("web token resource version %v is not supported", hdr.Version)
}