Livio Spring 8f88c4cf5b
feat: add PKCE option to generic OAuth2 / OIDC identity providers (#9373)
# Which Problems Are Solved

Some OAuth2 and OIDC providers require the use of PKCE for all their
clients. While ZITADEL already recommended the same for its clients, it
did not yet support the option on the IdP configuration.

# How the Problems Are Solved

- A new boolean `use_pkce` is added to the add/update generic OAuth/OIDC
endpoints.
- A new checkbox is added to the generic OAuth and OIDC provider
templates.
- The `rp.WithPKCE` option is added to the provider if the use of PKCE
has been set.
- The `rp.WithCodeChallenge` and `rp.WithCodeVerifier` options are added
to the OIDC/Auth BeginAuth and CodeExchange function.
- Store verifier or any other persistent argument in the intent or auth
request.
- Create corresponding session object before creating the intent, to be
able to store the information.
- (refactored session structs to use a constructor for unified creation
and better overview of actual usage)

Here's a screenshot showing the URI including the PKCE params:


![use_pkce_in_url](https://github.com/zitadel/zitadel/assets/30386061/eaeab123-a5da-4826-b001-2ae9efa35169)

# Additional Changes

None.

# Additional Context

- Closes #6449
- This PR replaces the existing PR (#8228) of @doncicuto. The base he
did was cherry picked. Thank you very much for that!

---------

Co-authored-by: Miguel Cabrerizo <doncicuto@gmail.com>
Co-authored-by: Stefan Benz <46600784+stebenz@users.noreply.github.com>
2025-02-26 12:20:47 +00:00

69 lines
2.0 KiB
Go

package apple
import (
"context"
"encoding/json"
openid "github.com/zitadel/oidc/v3/pkg/oidc"
"github.com/zitadel/zitadel/internal/idp"
"github.com/zitadel/zitadel/internal/idp/providers/oidc"
)
// Session extends the [oidc.Session] with the formValues returned from the callback.
// This enables to parse the user (name and email), which Apple only returns as form params on registration
type Session struct {
*oidc.Session
UserFormValue string
}
func NewSession(provider *Provider, code, userFormValue string) *Session {
return &Session{Session: oidc.NewSession(provider.Provider, code, nil), UserFormValue: userFormValue}
}
type userFormValue struct {
Name userNamesFormValue `json:"name,omitempty" schema:"name"`
}
type userNamesFormValue struct {
FirstName string `json:"firstName,omitempty" schema:"firstName"`
LastName string `json:"lastName,omitempty" schema:"lastName"`
}
// FetchUser implements the [idp.Session] interface.
// It will execute an OIDC code exchange if needed to retrieve the tokens,
// extract the information from the id_token and if available also from the `user` form value.
// The information will be mapped into an [idp.User].
func (s *Session) FetchUser(ctx context.Context) (user idp.User, err error) {
if s.Tokens == nil {
if err = s.Authorize(ctx); err != nil {
return nil, err
}
}
info := s.Tokens.IDTokenClaims.GetUserInfo()
userName := userFormValue{}
if s.UserFormValue != "" {
if err = json.Unmarshal([]byte(s.UserFormValue), &userName); err != nil {
return nil, err
}
}
return NewUser(info, userName.Name), nil
}
func NewUser(info *openid.UserInfo, names userNamesFormValue) *User {
user := oidc.NewUser(info)
user.GivenName = names.FirstName
user.FamilyName = names.LastName
return &User{User: user}
}
// User extends the [oidc.User] by returning the email as preferred_username, since Apple does not return the latter.
type User struct {
*oidc.User
}
func (u *User) GetPreferredUsername() string {
return u.Email
}