grafana/pkg/api/login_oauth.go
2022-02-07 14:36:15 +01:00

359 lines
11 KiB
Go

package api
import (
"context"
"crypto/rand"
"crypto/sha256"
"encoding/base64"
"encoding/hex"
"errors"
"fmt"
"net/http"
"net/url"
"github.com/grafana/grafana/pkg/api/response"
"github.com/grafana/grafana/pkg/infra/log"
"github.com/grafana/grafana/pkg/infra/metrics"
"github.com/grafana/grafana/pkg/login"
"github.com/grafana/grafana/pkg/login/social"
"github.com/grafana/grafana/pkg/middleware/cookies"
"github.com/grafana/grafana/pkg/models"
"github.com/grafana/grafana/pkg/setting"
"github.com/grafana/grafana/pkg/web"
"golang.org/x/oauth2"
)
var (
oauthLogger = log.New("oauth")
)
const (
OauthStateCookieName = "oauth_state"
OauthPKCECookieName = "oauth_code_verifier"
)
func GenStateString() (string, error) {
rnd := make([]byte, 32)
if _, err := rand.Read(rnd); err != nil {
oauthLogger.Error("failed to generate state string", "err", err)
return "", err
}
return base64.URLEncoding.EncodeToString(rnd), nil
}
// genPKCECode returns a random URL-friendly string and it's base64 URL encoded SHA256 digest.
func genPKCECode() (string, string, error) {
// IETF RFC 7636 specifies that the code verifier should be 43-128
// characters from a set of unreserved URI characters which is
// almost the same as the set of characters in base64url.
// https://datatracker.ietf.org/doc/html/rfc7636#section-4.1
//
// It doesn't hurt to generate a few more bytes here, we generate
// 96 bytes which we then encode using base64url to make sure
// they're within the set of unreserved characters.
//
// 96 is chosen because 96*8/6 = 128, which means that we'll have
// 128 characters after it has been base64 encoded.
raw := make([]byte, 96)
_, err := rand.Read(raw)
if err != nil {
return "", "", err
}
ascii := make([]byte, 128)
base64.RawURLEncoding.Encode(ascii, raw)
shasum := sha256.Sum256(ascii)
pkce := base64.RawURLEncoding.EncodeToString(shasum[:])
return string(ascii), pkce, nil
}
func (hs *HTTPServer) OAuthLogin(ctx *models.ReqContext) response.Response {
loginInfo := models.LoginInfo{
AuthModule: "oauth",
}
name := web.Params(ctx.Req)[":name"]
loginInfo.AuthModule = name
provider := hs.SocialService.GetOAuthInfoProvider(name)
if provider == nil {
hs.handleOAuthLoginError(ctx, loginInfo, LoginError{
HttpStatus: http.StatusNotFound,
PublicMessage: "OAuth not enabled",
})
return nil
}
connect, err := hs.SocialService.GetConnector(name)
if err != nil {
hs.handleOAuthLoginError(ctx, loginInfo, LoginError{
HttpStatus: http.StatusNotFound,
PublicMessage: fmt.Sprintf("No OAuth with name %s configured", name),
})
return nil
}
errorParam := ctx.Query("error")
if errorParam != "" {
errorDesc := ctx.Query("error_description")
oauthLogger.Error("failed to login ", "error", errorParam, "errorDesc", errorDesc)
hs.handleOAuthLoginErrorWithRedirect(ctx, loginInfo, login.ErrProviderDeniedRequest, "error", errorParam, "errorDesc", errorDesc)
return nil
}
code := ctx.Query("code")
if code == "" {
opts := []oauth2.AuthCodeOption{oauth2.AccessTypeOnline}
if provider.UsePKCE {
ascii, pkce, err := genPKCECode()
if err != nil {
ctx.Logger.Error("Generating PKCE failed", "error", err)
hs.handleOAuthLoginError(ctx, loginInfo, LoginError{
HttpStatus: http.StatusInternalServerError,
PublicMessage: "An internal error occurred",
})
}
cookies.WriteCookie(ctx.Resp, OauthPKCECookieName, ascii, hs.Cfg.OAuthCookieMaxAge, hs.CookieOptionsFromCfg)
opts = append(opts,
oauth2.SetAuthURLParam("code_challenge", pkce),
oauth2.SetAuthURLParam("code_challenge_method", "S256"),
)
}
state, err := GenStateString()
if err != nil {
ctx.Logger.Error("Generating state string failed", "err", err)
hs.handleOAuthLoginError(ctx, loginInfo, LoginError{
HttpStatus: http.StatusInternalServerError,
PublicMessage: "An internal error occurred",
})
return nil
}
hashedState := hashStatecode(state, provider.ClientSecret)
cookies.WriteCookie(ctx.Resp, OauthStateCookieName, hashedState, hs.Cfg.OAuthCookieMaxAge, hs.CookieOptionsFromCfg)
if provider.HostedDomain != "" {
opts = append(opts, oauth2.SetAuthURLParam("hd", provider.HostedDomain))
}
ctx.Redirect(connect.AuthCodeURL(state, opts...))
return nil
}
cookieState := ctx.GetCookie(OauthStateCookieName)
// delete cookie
cookies.DeleteCookie(ctx.Resp, OauthStateCookieName, hs.CookieOptionsFromCfg)
if cookieState == "" {
hs.handleOAuthLoginError(ctx, loginInfo, LoginError{
HttpStatus: http.StatusInternalServerError,
PublicMessage: "login.OAuthLogin(missing saved state)",
})
return nil
}
queryState := hashStatecode(ctx.Query("state"), provider.ClientSecret)
oauthLogger.Info("state check", "queryState", queryState, "cookieState", cookieState)
if cookieState != queryState {
hs.handleOAuthLoginError(ctx, loginInfo, LoginError{
HttpStatus: http.StatusInternalServerError,
PublicMessage: "login.OAuthLogin(state mismatch)",
})
return nil
}
oauthClient, err := hs.SocialService.GetOAuthHttpClient(name)
if err != nil {
ctx.Logger.Error("Failed to create OAuth http client", "error", err)
hs.handleOAuthLoginError(ctx, loginInfo, LoginError{
HttpStatus: http.StatusInternalServerError,
PublicMessage: "login.OAuthLogin(" + err.Error() + ")",
})
return nil
}
oauthCtx := context.WithValue(context.Background(), oauth2.HTTPClient, oauthClient)
opts := []oauth2.AuthCodeOption{}
codeVerifier := ctx.GetCookie(OauthPKCECookieName)
cookies.DeleteCookie(ctx.Resp, OauthPKCECookieName, hs.CookieOptionsFromCfg)
if codeVerifier != "" {
opts = append(opts,
oauth2.SetAuthURLParam("code_verifier", codeVerifier),
)
}
// get token from provider
token, err := connect.Exchange(oauthCtx, code, opts...)
if err != nil {
hs.handleOAuthLoginError(ctx, loginInfo, LoginError{
HttpStatus: http.StatusInternalServerError,
PublicMessage: "login.OAuthLogin(NewTransportWithCode)",
Err: err,
})
return nil
}
// token.TokenType was defaulting to "bearer", which is out of spec, so we explicitly set to "Bearer"
token.TokenType = "Bearer"
oauthLogger.Debug("OAuthLogin Got token", "token", token)
// set up oauth2 client
client := connect.Client(oauthCtx, token)
// get user info
userInfo, err := connect.UserInfo(client, token)
if err != nil {
var sErr *social.Error
if errors.As(err, &sErr) {
hs.handleOAuthLoginErrorWithRedirect(ctx, loginInfo, sErr)
} else {
hs.handleOAuthLoginError(ctx, loginInfo, LoginError{
HttpStatus: http.StatusInternalServerError,
PublicMessage: fmt.Sprintf("login.OAuthLogin(get info from %s)", name),
Err: err,
})
}
return nil
}
oauthLogger.Debug("OAuthLogin got user info", "userInfo", userInfo)
// validate that we got at least an email address
if userInfo.Email == "" {
hs.handleOAuthLoginErrorWithRedirect(ctx, loginInfo, login.ErrNoEmail)
return nil
}
// validate that the email is allowed to login to grafana
if !connect.IsEmailAllowed(userInfo.Email) {
hs.handleOAuthLoginErrorWithRedirect(ctx, loginInfo, login.ErrEmailNotAllowed)
return nil
}
loginInfo.ExternalUser = *buildExternalUserInfo(token, userInfo, name)
loginInfo.User, err = hs.SyncUser(ctx, &loginInfo.ExternalUser, connect)
if err != nil {
hs.handleOAuthLoginErrorWithRedirect(ctx, loginInfo, err)
return nil
}
// login
if err := hs.loginUserWithUser(loginInfo.User, ctx); err != nil {
hs.handleOAuthLoginErrorWithRedirect(ctx, loginInfo, err)
return nil
}
loginInfo.HTTPStatus = http.StatusOK
hs.HooksService.RunLoginHook(&loginInfo, ctx)
metrics.MApiLoginOAuth.Inc()
if redirectTo, err := url.QueryUnescape(ctx.GetCookie("redirect_to")); err == nil && len(redirectTo) > 0 {
if err := hs.ValidateRedirectTo(redirectTo); err == nil {
cookies.DeleteCookie(ctx.Resp, "redirect_to", hs.CookieOptionsFromCfg)
ctx.Redirect(redirectTo)
return nil
}
ctx.Logger.Debug("Ignored invalid redirect_to cookie value", "redirect_to", redirectTo)
}
ctx.Redirect(setting.AppSubUrl + "/")
return nil
}
// buildExternalUserInfo returns a ExternalUserInfo struct from OAuth user profile
func buildExternalUserInfo(token *oauth2.Token, userInfo *social.BasicUserInfo, name string) *models.ExternalUserInfo {
oauthLogger.Debug("Building external user info from OAuth user info")
extUser := &models.ExternalUserInfo{
AuthModule: fmt.Sprintf("oauth_%s", name),
OAuthToken: token,
AuthId: userInfo.Id,
Name: userInfo.Name,
Login: userInfo.Login,
Email: userInfo.Email,
OrgRoles: map[int64]models.RoleType{},
Groups: userInfo.Groups,
}
if userInfo.Role != "" {
rt := models.RoleType(userInfo.Role)
if rt.IsValid() {
// The user will be assigned a role in either the auto-assigned organization or in the default one
var orgID int64
if setting.AutoAssignOrg && setting.AutoAssignOrgId > 0 {
orgID = int64(setting.AutoAssignOrgId)
plog.Debug("The user has a role assignment and organization membership is auto-assigned",
"role", userInfo.Role, "orgId", orgID)
} else {
orgID = int64(1)
plog.Debug("The user has a role assignment and organization membership is not auto-assigned",
"role", userInfo.Role, "orgId", orgID)
}
extUser.OrgRoles[orgID] = rt
}
}
return extUser
}
// SyncUser syncs a Grafana user profile with the corresponding OAuth profile.
func (hs *HTTPServer) SyncUser(
ctx *models.ReqContext,
extUser *models.ExternalUserInfo,
connect social.SocialConnector,
) (*models.User, error) {
oauthLogger.Debug("Syncing Grafana user with corresponding OAuth profile")
// add/update user in Grafana
cmd := &models.UpsertUserCommand{
ReqContext: ctx,
ExternalUser: extUser,
SignupAllowed: connect.IsSignupAllowed(),
}
if err := hs.Login.UpsertUser(ctx.Req.Context(), cmd); err != nil {
return nil, err
}
// Do not expose disabled status,
// just show incorrect user credentials error (see #17947)
if cmd.Result.IsDisabled {
oauthLogger.Warn("User is disabled", "user", cmd.Result.Login)
return nil, login.ErrInvalidCredentials
}
return cmd.Result, nil
}
func hashStatecode(code, seed string) string {
hashBytes := sha256.Sum256([]byte(code + setting.SecretKey + seed))
return hex.EncodeToString(hashBytes[:])
}
type LoginError struct {
HttpStatus int
PublicMessage string
Err error
}
func (hs *HTTPServer) handleOAuthLoginError(ctx *models.ReqContext, info models.LoginInfo, err LoginError) {
ctx.Handle(hs.Cfg, err.HttpStatus, err.PublicMessage, err.Err)
info.Error = err.Err
if info.Error == nil {
info.Error = errors.New(err.PublicMessage)
}
info.HTTPStatus = err.HttpStatus
hs.HooksService.RunLoginHook(&info, ctx)
}
func (hs *HTTPServer) handleOAuthLoginErrorWithRedirect(ctx *models.ReqContext, info models.LoginInfo, err error, v ...interface{}) {
hs.redirectWithError(ctx, err, v...)
info.Error = err
hs.HooksService.RunLoginHook(&info, ctx)
}