Refactor switching login type code into app layer and add v4 endpoint (#6000)

* Refactor switching login type code into app layer and add v4 endpoint

* Fix unit test

app/oauth.go

@@ -4,11 +4,20 @@
 package app
 
 import (
+	"crypto/tls"
+	b64 "encoding/base64"
+	"io"
+	"io/ioutil"
+	"net/http"
+	"net/url"
+	"strings"
+
+	l4g "github.com/alecthomas/log4go"
 	"github.com/mattermost/platform/model"
+	"github.com/mattermost/platform/utils"
 )
 
 func RevokeAccessToken(token string) *model.AppError {
-
 	session, _ := GetSession(token)
 	schan := Srv.Store.Session().Remove(token)
 
@@ -32,3 +41,164 @@ func RevokeAccessToken(token string) *model.AppError {
 
 	return nil
 }
+
+func GetAuthorizationCode(service string, props map[string]string, loginHint string) (string, *model.AppError) {
+	sso := utils.Cfg.GetSSOService(service)
+	if sso != nil && !sso.Enable {
+		return "", model.NewLocAppError("GetAuthorizationCode", "api.user.get_authorization_code.unsupported.app_error", nil, "service="+service)
+	}
+
+	clientId := sso.Id
+	endpoint := sso.AuthEndpoint
+	scope := sso.Scope
+
+	props["hash"] = model.HashPassword(clientId)
+	state := b64.StdEncoding.EncodeToString([]byte(model.MapToJson(props)))
+
+	redirectUri := utils.GetSiteURL() + "/signup/" + service + "/complete"
+
+	authUrl := endpoint + "?response_type=code&client_id=" + clientId + "&redirect_uri=" + url.QueryEscape(redirectUri) + "&state=" + url.QueryEscape(state)
+
+	if len(scope) > 0 {
+		authUrl += "&scope=" + utils.UrlEncode(scope)
+	}
+
+	if len(loginHint) > 0 {
+		authUrl += "&login_hint=" + utils.UrlEncode(loginHint)
+	}
+
+	return authUrl, nil
+}
+
+func AuthorizeOAuthUser(service, code, state, redirectUri string) (io.ReadCloser, string, map[string]string, *model.AppError) {
+	sso := utils.Cfg.GetSSOService(service)
+	if sso == nil || !sso.Enable {
+		return nil, "", nil, model.NewLocAppError("AuthorizeOAuthUser", "api.user.authorize_oauth_user.unsupported.app_error", nil, "service="+service)
+	}
+
+	stateStr := ""
+	if b, err := b64.StdEncoding.DecodeString(state); err != nil {
+		return nil, "", nil, model.NewLocAppError("AuthorizeOAuthUser", "api.user.authorize_oauth_user.invalid_state.app_error", nil, err.Error())
+	} else {
+		stateStr = string(b)
+	}
+
+	stateProps := model.MapFromJson(strings.NewReader(stateStr))
+
+	if !model.ComparePassword(stateProps["hash"], sso.Id) {
+		return nil, "", nil, model.NewLocAppError("AuthorizeOAuthUser", "api.user.authorize_oauth_user.invalid_state.app_error", nil, "")
+	}
+
+	teamId := stateProps["team_id"]
+
+	p := url.Values{}
+	p.Set("client_id", sso.Id)
+	p.Set("client_secret", sso.Secret)
+	p.Set("code", code)
+	p.Set("grant_type", model.ACCESS_TOKEN_GRANT_TYPE)
+	p.Set("redirect_uri", redirectUri)
+
+	tr := &http.Transport{
+		TLSClientConfig: &tls.Config{InsecureSkipVerify: *utils.Cfg.ServiceSettings.EnableInsecureOutgoingConnections},
+	}
+	client := &http.Client{Transport: tr}
+	req, _ := http.NewRequest("POST", sso.TokenEndpoint, strings.NewReader(p.Encode()))
+
+	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
+	req.Header.Set("Accept", "application/json")
+
+	var ar *model.AccessResponse
+	var respBody []byte
+	if resp, err := client.Do(req); err != nil {
+		return nil, "", nil, model.NewLocAppError("AuthorizeOAuthUser", "api.user.authorize_oauth_user.token_failed.app_error", nil, err.Error())
+	} else {
+		ar = model.AccessResponseFromJson(resp.Body)
+		defer func() {
+			ioutil.ReadAll(resp.Body)
+			resp.Body.Close()
+		}()
+		if ar == nil {
+			return nil, "", nil, model.NewLocAppError("AuthorizeOAuthUser", "api.user.authorize_oauth_user.bad_response.app_error", nil, "")
+		}
+	}
+
+	if strings.ToLower(ar.TokenType) != model.ACCESS_TOKEN_TYPE {
+		return nil, "", nil, model.NewLocAppError("AuthorizeOAuthUser", "api.user.authorize_oauth_user.bad_token.app_error", nil, "token_type="+ar.TokenType+", response_body="+string(respBody))
+	}
+
+	if len(ar.AccessToken) == 0 {
+		return nil, "", nil, model.NewLocAppError("AuthorizeOAuthUser", "api.user.authorize_oauth_user.missing.app_error", nil, "")
+	}
+
+	p = url.Values{}
+	p.Set("access_token", ar.AccessToken)
+	req, _ = http.NewRequest("GET", sso.UserApiEndpoint, strings.NewReader(""))
+
+	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
+	req.Header.Set("Accept", "application/json")
+	req.Header.Set("Authorization", "Bearer "+ar.AccessToken)
+
+	if resp, err := client.Do(req); err != nil {
+		return nil, "", nil, model.NewLocAppError("AuthorizeOAuthUser", "api.user.authorize_oauth_user.service.app_error",
+			map[string]interface{}{"Service": service}, err.Error())
+	} else {
+		return resp.Body, teamId, stateProps, nil
+	}
+
+}
+
+func SwitchEmailToOAuth(email, password, code, service string) (string, *model.AppError) {
+	var user *model.User
+	var err *model.AppError
+	if user, err = GetUserByEmail(email); err != nil {
+		return "", err
+	}
+
+	if err := CheckPasswordAndAllCriteria(user, password, code); err != nil {
+		return "", err
+	}
+
+	stateProps := map[string]string{}
+	stateProps["action"] = model.OAUTH_ACTION_EMAIL_TO_SSO
+	stateProps["email"] = email
+
+	if service == model.USER_AUTH_SERVICE_SAML {
+		return utils.GetSiteURL() + "/login/sso/saml?action=" + model.OAUTH_ACTION_EMAIL_TO_SSO + "&email=" + email, nil
+	} else {
+		if authUrl, err := GetAuthorizationCode(service, stateProps, ""); err != nil {
+			return "", err
+		} else {
+			return authUrl, nil
+		}
+	}
+}
+
+func SwitchOAuthToEmail(email, password, requesterId string) (string, *model.AppError) {
+	var user *model.User
+	var err *model.AppError
+	if user, err = GetUserByEmail(email); err != nil {
+		return "", err
+	}
+
+	if user.Id != requesterId {
+		return "", model.NewAppError("SwitchOAuthToEmail", "api.user.oauth_to_email.context.app_error", nil, "", http.StatusForbidden)
+	}
+
+	if err := UpdatePassword(user, password); err != nil {
+		return "", err
+	}
+
+	T := utils.GetUserTranslations(user.Locale)
+
+	go func() {
+		if err := SendSignInChangeEmail(user.Email, T("api.templates.signin_change_email.body.method_email"), user.Locale, utils.GetSiteURL()); err != nil {
+			l4g.Error(err.Error())
+		}
+	}()
+
+	if err := RevokeAllSessions(requesterId); err != nil {
+		return "", err
+	}
+
+	return "/login?extra=signin_change", nil
+}