apiserver.go

/*
Copyright 2015 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 auth

import (
	"encoding/json"
	"fmt"
	"net/http"
	"net/url"
	"strconv"
	"time"

	"github.com/gravitational/teleport"
	"github.com/gravitational/teleport/lib/events"
	"github.com/gravitational/teleport/lib/httplib"
	"github.com/gravitational/teleport/lib/services"
	"github.com/gravitational/teleport/lib/session"
	"github.com/gravitational/teleport/lib/utils"

	log "github.com/Sirupsen/logrus"
	"github.com/gravitational/trace"
	"github.com/julienschmidt/httprouter"

	"github.com/tstranex/u2f"
)

type APIConfig struct {
	AuthServer     *AuthServer
	SessionService session.Service
	AuditLog       events.IAuditLog
	Authorizer     Authorizer
}

// APIServer implements http API server for AuthServer interface
type APIServer struct {
	APIConfig
	httprouter.Router
}

// NewAPIServer returns a new instance of APIServer HTTP handler
func NewAPIServer(config *APIConfig) http.Handler {
	srv := APIServer{
		APIConfig: *config,
	}
	srv.Router = *httprouter.New()

	// Operations on certificate authorities
	srv.GET("/:version/domain", srv.withAuth(srv.getDomainName))
	srv.POST("/:version/authorities/:type", srv.withAuth(srv.upsertCertAuthority))
	srv.DELETE("/:version/authorities/:type/:domain", srv.withAuth(srv.deleteCertAuthority))
	srv.GET("/:version/authorities/:type/:domain", srv.withAuth(srv.getCertAuthority))
	srv.GET("/:version/authorities/:type", srv.withAuth(srv.getCertAuthorities))

	// Generating certificates for user and host authorities
	srv.POST("/:version/ca/host/certs", srv.withAuth(srv.generateHostCert))
	srv.POST("/:version/ca/user/certs", srv.withAuth(srv.generateUserCert))

	// Operations on users
	srv.GET("/:version/users", srv.withAuth(srv.getUsers))
	srv.GET("/:version/users/:user", srv.withAuth(srv.getUser))
	srv.DELETE("/:version/users/:user", srv.withAuth(srv.deleteUser))

	// Generating keypairs
	srv.POST("/:version/keypair", srv.withAuth(srv.generateKeyPair))

	// Passwords and sessions
	srv.POST("/:version/users", srv.withAuth(srv.upsertUser))
	srv.POST("/:version/users/:user/web/password", srv.withAuth(srv.upsertPassword))
	srv.POST("/:version/users/:user/web/password/check", srv.withAuth(srv.checkPassword))
	srv.POST("/:version/users/:user/web/signin", srv.withAuth(srv.signIn))
	srv.GET("/:version/users/:user/web/signin/preauth", srv.withAuth(srv.preAuthenticatedSignIn))
	srv.POST("/:version/users/:user/web/sessions", srv.withAuth(srv.createWebSession))
	srv.GET("/:version/users/:user/web/sessions/:sid", srv.withAuth(srv.getWebSession))
	srv.DELETE("/:version/users/:user/web/sessions/:sid", srv.withAuth(srv.deleteWebSession))
	srv.GET("/:version/signuptokens/:token", srv.withAuth(srv.getSignupTokenData))
	srv.POST("/:version/signuptokens/users", srv.withAuth(srv.createUserWithToken))
	srv.POST("/:version/signuptokens", srv.withAuth(srv.createSignupToken))

	// Servers and presence heartbeat
	srv.POST("/:version/namespaces/:namespace/nodes", srv.withAuth(srv.upsertNode))
	srv.GET("/:version/namespaces/:namespace/nodes", srv.withAuth(srv.getNodes))
	srv.POST("/:version/authservers", srv.withAuth(srv.upsertAuthServer))
	srv.GET("/:version/authservers", srv.withAuth(srv.getAuthServers))
	srv.POST("/:version/proxies", srv.withAuth(srv.upsertProxy))
	srv.GET("/:version/proxies", srv.withAuth(srv.getProxies))

	// Reverse tunnels
	srv.POST("/:version/reversetunnels", srv.withAuth(srv.upsertReverseTunnel))
	srv.GET("/:version/reversetunnels", srv.withAuth(srv.getReverseTunnels))
	srv.DELETE("/:version/reversetunnels/:domain", srv.withAuth(srv.deleteReverseTunnel))

	// trusted clusters
	srv.POST("/:version/trustedclusters", srv.withAuth(srv.upsertTrustedCluster))
	srv.POST("/:version/trustedclusters/validate", srv.withAuth(srv.validateTrustedCluster))
	srv.GET("/:version/trustedclusters", srv.withAuth(srv.getTrustedClusters))
	srv.GET("/:version/trustedclusters/:name", srv.withAuth(srv.getTrustedCluster))
	srv.DELETE("/:version/trustedclusters/:name", srv.withAuth(srv.deleteTrustedCluster))

	// Tokens
	srv.POST("/:version/tokens", srv.withAuth(srv.generateToken))
	srv.POST("/:version/tokens/register", srv.withAuth(srv.registerUsingToken))
	srv.POST("/:version/tokens/register/auth", srv.withAuth(srv.registerNewAuthServer))

	// Sesssions
	srv.POST("/:version/namespaces/:namespace/sessions", srv.withAuth(srv.createSession))
	srv.PUT("/:version/namespaces/:namespace/sessions/:id", srv.withAuth(srv.updateSession))
	srv.GET("/:version/namespaces/:namespace/sessions", srv.withAuth(srv.getSessions))
	srv.GET("/:version/namespaces/:namespace/sessions/:id", srv.withAuth(srv.getSession))
	srv.POST("/:version/namespaces/:namespace/sessions/:id/stream", srv.withAuth(srv.postSessionChunk))
	srv.GET("/:version/namespaces/:namespace/sessions/:id/stream", srv.withAuth(srv.getSessionChunk))
	srv.GET("/:version/namespaces/:namespace/sessions/:id/events", srv.withAuth(srv.getSessionEvents))

	// Namespaces
	srv.POST("/:version/namespaces", srv.withAuth(srv.upsertNamespace))
	srv.GET("/:version/namespaces", srv.withAuth(srv.getNamespaces))
	srv.GET("/:version/namespaces/:namespace", srv.withAuth(srv.getNamespace))
	srv.DELETE("/:version/namespaces/:namespace", srv.withAuth(srv.deleteNamespace))

	// Roles
	srv.POST("/:version/roles", srv.withAuth(srv.upsertRole))
	srv.GET("/:version/roles", srv.withAuth(srv.getRoles))
	srv.GET("/:version/roles/:role", srv.withAuth(srv.getRole))
	srv.DELETE("/:version/roles/:role", srv.withAuth(srv.deleteRole))

	// cluster authentication preferences
	srv.GET("/:version/authentication/preference", srv.withAuth(srv.getClusterAuthPreference))
	srv.POST("/:version/authentication/preference", srv.withAuth(srv.setClusterAuthPreference))
	srv.GET("/:version/authentication/preference/u2f", srv.withAuth(srv.getUniversalSecondFactor))
	srv.POST("/:version/authentication/preference/u2f", srv.withAuth(srv.setUniversalSecondFactor))

	// OIDC
	srv.POST("/:version/oidc/connectors", srv.withAuth(srv.upsertOIDCConnector))
	srv.GET("/:version/oidc/connectors", srv.withAuth(srv.getOIDCConnectors))
	srv.GET("/:version/oidc/connectors/:id", srv.withAuth(srv.getOIDCConnector))
	srv.DELETE("/:version/oidc/connectors/:id", srv.withAuth(srv.deleteOIDCConnector))
	srv.POST("/:version/oidc/requests/create", srv.withAuth(srv.createOIDCAuthRequest))
	srv.POST("/:version/oidc/requests/validate", srv.withAuth(srv.validateOIDCAuthCallback))

	// U2F
	srv.GET("/:version/u2f/signuptokens/:token", srv.withAuth(srv.getSignupU2FRegisterRequest))
	srv.POST("/:version/u2f/users", srv.withAuth(srv.createUserWithU2FToken))
	srv.POST("/:version/u2f/users/:user/sign", srv.withAuth(srv.u2fSignRequest))
	srv.GET("/:version/u2f/appid", srv.withAuth(srv.getU2FAppID))

	// Provisioning tokens
	srv.GET("/:version/tokens", srv.withAuth(srv.getTokens))
	srv.GET("/:version/tokens/:token", srv.withAuth(srv.getToken))
	srv.DELETE("/:version/tokens/:token", srv.withAuth(srv.deleteToken))

	// Audit logs AKA events
	srv.POST("/:version/events", srv.withAuth(srv.emitAuditEvent))
	srv.GET("/:version/events", srv.withAuth(srv.searchEvents))

	return httplib.RewritePaths(&srv.Router,
		httplib.Rewrite("/v1/nodes", "/v1/namespaces/default/nodes"),
		httplib.Rewrite("/v1/sessions", "/v1/namespaces/default/sessions"),
		httplib.Rewrite("/v1/sessions/([^/]+)/(.*)", "/v1/namespaces/default/sessions/$1/$2"),
	)
}

// HandlerWithAuthFunc is http handler with passed auth context
type HandlerWithAuthFunc func(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error)

func (s *APIServer) withAuth(handler HandlerWithAuthFunc) httprouter.Handle {
	const accessDeniedMsg = "auth API: access denied "
	return httplib.MakeHandler(func(w http.ResponseWriter, r *http.Request, p httprouter.Params) (interface{}, error) {
		// SSH-to-HTTP gateway (tun server) expects the auth
		// context to be set by SSH server
		authContext, err := s.Authorizer.Authorize(r.Context())
		if err != nil {
			log.Warn(accessDeniedMsg + err.Error())
			return nil, trace.AccessDenied(accessDeniedMsg + "[00]")
		}
		auth := &AuthWithRoles{
			authServer: s.AuthServer,
			user:       authContext.Username,
			checker:    authContext.Checker,
			sessions:   s.SessionService,
			alog:       s.AuditLog,
		}
		version := p.ByName("version")
		if version == "" {
			return nil, trace.BadParameter("missing version")
		}
		return handler(auth, w, r, p, version)
	})
}

type upsertServerRawReq struct {
	Server json.RawMessage `json:"server"`
	TTL    time.Duration   `json:"ttl"`
}

// upsertServer is a common utility function
func (s *APIServer) upsertServer(auth ClientI, role teleport.Role, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	var req upsertServerRawReq
	if err := httplib.ReadJSON(r, &req); err != nil {
		return nil, trace.Wrap(err)
	}
	var kind string
	switch role {
	case teleport.RoleNode:
		kind = services.KindNode
	case teleport.RoleAuth:
		kind = services.KindAuthServer
	case teleport.RoleProxy:
		kind = services.KindProxy
	}
	server, err := services.GetServerMarshaler().UnmarshalServer(req.Server, kind)
	if err != nil {
		return nil, trace.Wrap(err)
	}
	// if server sent "local" IP address to us, replace the ip/host part with the remote address we see
	// on the socket, but keep the original port:
	server.SetAddr(utils.ReplaceLocalhost(server.GetAddr(), r.RemoteAddr))

	switch role {
	case teleport.RoleNode:
		server.SetNamespace(p.ByName("namespace"))
		if err := auth.UpsertNode(server, req.TTL); err != nil {
			return nil, trace.Wrap(err)
		}
	case teleport.RoleAuth:
		if err := auth.UpsertAuthServer(server, req.TTL); err != nil {
			return nil, trace.Wrap(err)
		}
	case teleport.RoleProxy:
		if err := auth.UpsertProxy(server, req.TTL); err != nil {
			return nil, trace.Wrap(err)
		}
	}
	return message("ok"), nil
}

// upsertNode is called by remote SSH nodes when they ping back into the auth service
func (s *APIServer) upsertNode(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	return s.upsertServer(auth, teleport.RoleNode, w, r, p, version)
}

// getNodes returns registered SSH nodes
func (s *APIServer) getNodes(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	servers, err := auth.GetNodes(p.ByName("namespace"))
	if err != nil {
		return nil, trace.Wrap(err)
	}
	return marshalServers(servers, version)
}

// upsertProxy is called by remote SSH nodes when they ping back into the auth service
func (s *APIServer) upsertProxy(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	return s.upsertServer(auth, teleport.RoleProxy, w, r, p, version)
}

// getProxies returns registered proxies
func (s *APIServer) getProxies(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	servers, err := auth.GetProxies()
	if err != nil {
		return nil, trace.Wrap(err)
	}
	return marshalServers(servers, version)
}

// upsertAuthServer is called by remote Auth servers when they ping back into the auth service
func (s *APIServer) upsertAuthServer(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	return s.upsertServer(auth, teleport.RoleAuth, w, r, p, version)
}

// getAuthServers returns registered auth servers
func (s *APIServer) getAuthServers(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	servers, err := auth.GetAuthServers()
	if err != nil {
		return nil, trace.Wrap(err)
	}
	return marshalServers(servers, version)
}

func marshalServers(servers []services.Server, version string) (interface{}, error) {
	items := make([]json.RawMessage, len(servers))
	for i, server := range servers {
		data, err := services.GetServerMarshaler().MarshalServer(server, services.WithVersion(version))
		if err != nil {
			return nil, trace.Wrap(err)
		}
		items[i] = data
	}
	return items, nil
}

type upsertReverseTunnelRawReq struct {
	ReverseTunnel json.RawMessage `json:"reverse_tunnel"`
	TTL           time.Duration   `json:"ttl"`
}

// upsertReverseTunnel is called by admin to create a reverse tunnel to remote proxy
func (s *APIServer) upsertReverseTunnel(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	var req upsertReverseTunnelRawReq
	if err := httplib.ReadJSON(r, &req); err != nil {
		return nil, trace.Wrap(err)
	}
	tun, err := services.GetReverseTunnelMarshaler().UnmarshalReverseTunnel(req.ReverseTunnel)
	if err != nil {
		return nil, trace.Wrap(err)
	}
	if err := auth.UpsertReverseTunnel(tun, req.TTL); err != nil {
		return nil, trace.Wrap(err)
	}
	return message("ok"), nil
}

// getReverseTunnels returns a list of reverse tunnels
func (s *APIServer) getReverseTunnels(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	reverseTunnels, err := auth.GetReverseTunnels()
	if err != nil {
		return nil, trace.Wrap(err)
	}
	items := make([]json.RawMessage, len(reverseTunnels))
	for i, tunnel := range reverseTunnels {
		data, err := services.GetReverseTunnelMarshaler().MarshalReverseTunnel(tunnel, services.WithVersion(version))
		if err != nil {
			return nil, trace.Wrap(err)
		}
		items[i] = data
	}
	return items, nil
}

// deleteReverseTunnel deletes reverse tunnel
func (s *APIServer) deleteReverseTunnel(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	domainName := p.ByName("domain")
	err := auth.DeleteReverseTunnel(domainName)
	if err != nil {
		return nil, trace.Wrap(err)
	}
	return message(fmt.Sprintf("reverse tunnel %v deleted", domainName)), nil
}

type upsertTrustedClusterReq struct {
	TrustedCluster json.RawMessage `json:"trusted_cluster"`
}

func (s *APIServer) upsertTrustedCluster(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	var req *upsertTrustedClusterReq
	if err := httplib.ReadJSON(r, &req); err != nil {
		return nil, trace.Wrap(err)
	}
	trustedCluster, err := services.GetTrustedClusterMarshaler().Unmarshal(req.TrustedCluster)
	if err != nil {
		return nil, trace.Wrap(err)
	}

	err = auth.UpsertTrustedCluster(trustedCluster)
	if err != nil {
		return nil, trace.Wrap(err)
	}

	return message("ok"), nil
}

func (s *APIServer) validateTrustedCluster(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	var validateRequestRaw ValidateTrustedClusterRequestRaw
	if err := httplib.ReadJSON(r, &validateRequestRaw); err != nil {
		return nil, trace.Wrap(err)
	}

	validateRequest, err := validateRequestRaw.ToNative()
	if err != nil {
		return nil, trace.Wrap(err)
	}

	validateResponse, err := auth.ValidateTrustedCluster(validateRequest)
	if err != nil {
		return nil, trace.Wrap(err)
	}

	validateResponseRaw, err := validateResponse.ToRaw()
	if err != nil {
		return nil, trace.Wrap(err)
	}

	return validateResponseRaw, nil
}

func (s *APIServer) getTrustedCluster(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	return auth.GetTrustedCluster(p.ByName("name"))
}

func (s *APIServer) getTrustedClusters(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	return auth.GetTrustedClusters()
}

func (s *APIServer) deleteTrustedCluster(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	err := auth.DeleteTrustedCluster(p.ByName("name"))
	if err != nil {
		return nil, trace.Wrap(err)
	}

	return message("ok"), nil
}

// getTokens returns a list of active provisioning tokens. expired (inactive) tokens are not returned
func (s *APIServer) getTokens(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	tokens, err := auth.GetTokens()
	if err != nil {
		return nil, trace.Wrap(err)
	}
	return tokens, nil
}

// getTokens returns provisioning token by name
func (s *APIServer) getToken(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	token, err := auth.GetToken(p.ByName("token"))
	if err != nil {
		return nil, trace.Wrap(err)
	}
	return token, nil
}

// deleteToken deletes (revokes) a token by its value
func (s *APIServer) deleteToken(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	token := p.ByName("token")
	if err := auth.DeleteToken(token); err != nil {
		return nil, trace.Wrap(err)
	}
	return message(fmt.Sprintf("Token %v deleted", token)), nil
}

func (s *APIServer) deleteWebSession(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	user, sid := p.ByName("user"), p.ByName("sid")
	err := auth.DeleteWebSession(user, sid)
	if err != nil {
		return nil, trace.Wrap(err)
	}
	return message(fmt.Sprintf("session '%v' for user '%v' deleted", sid, user)), nil
}

// sessionV1 is a V1 style web session, used in legacy v1 API
type sessionV1 struct {
	// ID is a session ID
	ID string `json:"id"`
	// Username is a user this session belongs to
	Username string `json:"username"`
	// ExpiresAt is an optional expiry time, if set
	// that means this web session and all derived web sessions
	// can not continue after this time, used in OIDC use case
	// when expiry is set by external identity provider, so user
	// has to relogin (or later on we'd need to refresh the token)
	ExpiresAt time.Time `json:"expires_at"`
	// WS is a private keypair used for signing requests
	WS services.WebSessionV1 `json:"web"`
}

func (s *APIServer) getWebSession(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	user, sid := p.ByName("user"), p.ByName("sid")
	sess, err := auth.GetWebSessionInfo(user, sid)
	if err != nil {
		return nil, trace.Wrap(err)
	}
	if version == services.V1 {
		return &sessionV1{
			ID:        sess.GetName(),
			Username:  sess.GetUser(),
			ExpiresAt: sess.GetExpiryTime(),
			WS:        *(sess.V1()),
		}, nil
	}
	return rawMessage(services.GetWebSessionMarshaler().MarshalWebSession(sess, services.WithVersion(version)))
}

type signInReq struct {
	Password string `json:"password"`
}

func (s *APIServer) signIn(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	var req *signInReq
	if err := httplib.ReadJSON(r, &req); err != nil {
		return nil, trace.Wrap(err)
	}

	user := p.ByName("user")
	sess, err := auth.SignIn(user, []byte(req.Password))
	if err != nil {
		return nil, trace.Wrap(err)
	}
	return rawMessage(services.GetWebSessionMarshaler().MarshalWebSession(sess, services.WithVersion(version)))
}

func (s *APIServer) preAuthenticatedSignIn(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	user := p.ByName("user")
	sess, err := auth.PreAuthenticatedSignIn(user)
	if err != nil {
		return nil, trace.Wrap(err)
	}
	return rawMessage(services.GetWebSessionMarshaler().MarshalWebSession(sess, services.WithVersion(version)))
}

func (s *APIServer) u2fSignRequest(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	var req *signInReq
	if err := httplib.ReadJSON(r, &req); err != nil {
		return nil, trace.Wrap(err)
	}
	user := p.ByName("user")
	pass := []byte(req.Password)
	u2fSignReq, err := auth.GetU2FSignRequest(user, pass)
	if err != nil {
		return nil, trace.Wrap(err)
	}
	return u2fSignReq, nil
}

type createWebSessionReq struct {
	PrevSessionID string `json:"prev_session_id"`
}

func (s *APIServer) createWebSession(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	var req *createWebSessionReq
	if err := httplib.ReadJSON(r, &req); err != nil {
		return nil, trace.Wrap(err)
	}
	user := p.ByName("user")
	if req.PrevSessionID != "" {
		sess, err := auth.ExtendWebSession(user, req.PrevSessionID)
		if err != nil {
			return nil, trace.Wrap(err)
		}
		return sess, nil
	}
	sess, err := auth.CreateWebSession(user)
	if err != nil {
		return nil, trace.Wrap(err)
	}
	return rawMessage(services.GetWebSessionMarshaler().MarshalWebSession(sess, services.WithVersion(version)))
}

type upsertPasswordReq struct {
	Password string `json:"password"`
}

func (s *APIServer) upsertPassword(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	var req *upsertPasswordReq
	if err := httplib.ReadJSON(r, &req); err != nil {
		return nil, trace.Wrap(err)
	}

	user := p.ByName("user")
	err := auth.UpsertPassword(user, []byte(req.Password))
	if err != nil {
		return nil, trace.Wrap(err)
	}

	return message(fmt.Sprintf("password for for user %q upserted", user)), nil
}

type upsertUserRawReq struct {
	User json.RawMessage `json:"user"`
}

func (s *APIServer) upsertUser(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	var req *upsertUserRawReq
	if err := httplib.ReadJSON(r, &req); err != nil {
		return nil, trace.Wrap(err)
	}
	user, err := services.GetUserMarshaler().UnmarshalUser(req.User)
	if err != nil {
		return nil, trace.Wrap(err)
	}
	err = auth.UpsertUser(user)
	if err != nil {
		return nil, trace.Wrap(err)
	}
	return message(fmt.Sprintf("'%v' user upserted", user.GetName())), nil
}

type checkPasswordReq struct {
	Password string `json:"password"`
	OTPToken string `json:"otp_token"`
}

func (s *APIServer) checkPassword(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	var req checkPasswordReq
	if err := httplib.ReadJSON(r, &req); err != nil {
		return nil, trace.Wrap(err)
	}

	user := p.ByName("user")
	if err := auth.CheckPassword(user, []byte(req.Password), req.OTPToken); err != nil {
		return nil, trace.Wrap(err)
	}

	return message(fmt.Sprintf("%q user password matches", user)), nil
}

func (s *APIServer) getUser(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	user, err := auth.GetUser(p.ByName("user"))
	if err != nil {
		return nil, trace.Wrap(err)
	}
	return rawMessage(services.GetUserMarshaler().MarshalUser(user, services.WithVersion(version)))
}

func rawMessage(data []byte, err error) (interface{}, error) {
	if err != nil {
		return nil, trace.Wrap(err)
	}
	m := json.RawMessage(data)
	return &m, nil
}

func (s *APIServer) getUsers(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	users, err := auth.GetUsers()
	if err != nil {
		return nil, trace.Wrap(err)
	}
	out := make([]json.RawMessage, len(users))
	for i, user := range users {
		data, err := services.GetUserMarshaler().MarshalUser(user, services.WithVersion(version))
		if err != nil {
			return nil, trace.Wrap(err)
		}
		out[i] = data
	}
	return out, nil
}

func (s *APIServer) deleteUser(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	user := p.ByName("user")
	if err := auth.DeleteUser(user); err != nil {
		return nil, trace.Wrap(err)
	}
	return message(fmt.Sprintf("user '%v' deleted", user)), nil
}

type generateKeyPairReq struct {
	Password string `json:"password"`
}

type generateKeyPairResponse struct {
	PrivKey []byte `json:"privkey"`
	PubKey  string `json:"pubkey"`
}

func (s *APIServer) generateKeyPair(auth ClientI, w http.ResponseWriter, r *http.Request, _ httprouter.Params, version string) (interface{}, error) {
	var req *generateKeyPairReq
	if err := httplib.ReadJSON(r, &req); err != nil {
		return nil, trace.Wrap(err)
	}

	priv, pub, err := auth.GenerateKeyPair(req.Password)
	if err != nil {
		return nil, trace.Wrap(err)
	}
	return &generateKeyPairResponse{PrivKey: priv, PubKey: string(pub)}, nil
}

type generateHostCertReq struct {
	Key         []byte         `json:"key"`
	HostID      string         `json:"hostname"`
	NodeName    string         `json:"node_name"`
	ClusterName string         `json:"auth_domain"`
	Roles       teleport.Roles `json:"roles"`
	TTL         time.Duration  `json:"ttl"`
}

func (s *APIServer) generateHostCert(auth ClientI, w http.ResponseWriter, r *http.Request, _ httprouter.Params, version string) (interface{}, error) {
	var req *generateHostCertReq
	if err := httplib.ReadJSON(r, &req); err != nil {
		return nil, trace.Wrap(err)
	}

	cert, err := auth.GenerateHostCert(req.Key, req.HostID, req.NodeName, req.ClusterName, req.Roles, req.TTL)
	if err != nil {
		return nil, trace.Wrap(err)
	}

	return string(cert), nil
}

type generateUserCertReq struct {
	Key  []byte        `json:"key"`
	User string        `json:"user"`
	TTL  time.Duration `json:"ttl"`
}

func (s *APIServer) generateUserCert(auth ClientI, w http.ResponseWriter, r *http.Request, _ httprouter.Params, version string) (interface{}, error) {
	var req *generateUserCertReq
	if err := httplib.ReadJSON(r, &req); err != nil {
		return nil, trace.Wrap(err)
	}
	cert, err := auth.GenerateUserCert(req.Key, req.User, req.TTL)
	if err != nil {
		return nil, trace.Wrap(err)
	}
	return string(cert), nil
}

type generateTokenReq struct {
	Roles teleport.Roles `json:"roles"`
	TTL   time.Duration  `json:"ttl"`
}

func (s *APIServer) generateToken(auth ClientI, w http.ResponseWriter, r *http.Request, _ httprouter.Params, version string) (interface{}, error) {
	var req *generateTokenReq
	if err := httplib.ReadJSON(r, &req); err != nil {
		return nil, trace.Wrap(err)
	}
	token, err := auth.GenerateToken(req.Roles, req.TTL)
	if err != nil {
		return nil, trace.Wrap(err)
	}
	return string(token), nil
}

type registerUsingTokenReq struct {
	HostID   string        `json:"hostID"`
	NodeName string        `json:"node_name"`
	Role     teleport.Role `json:"role"`
	Token    string        `json:"token"`
}

func (s *APIServer) registerUsingToken(auth ClientI, w http.ResponseWriter, r *http.Request, _ httprouter.Params, version string) (interface{}, error) {
	var req *registerUsingTokenReq
	if err := httplib.ReadJSON(r, &req); err != nil {
		return nil, trace.Wrap(err)
	}

	keys, err := auth.RegisterUsingToken(req.Token, req.HostID, req.NodeName, req.Role)
	if err != nil {
		return nil, trace.Wrap(err)
	}

	return keys, nil
}

type registerNewAuthServerReq struct {
	Token string `json:"token"`
}

func (s *APIServer) registerNewAuthServer(auth ClientI, w http.ResponseWriter, r *http.Request, _ httprouter.Params, version string) (interface{}, error) {
	var req *registerNewAuthServerReq
	if err := httplib.ReadJSON(r, &req); err != nil {
		return nil, trace.Wrap(err)
	}
	err := auth.RegisterNewAuthServer(req.Token)
	if err != nil {
		return nil, trace.Wrap(err)
	}
	return message("ok"), nil
}

type upsertCertAuthorityRawReq struct {
	CA  json.RawMessage `json:"ca"`
	TTL time.Duration   `json:"ttl"`
}

func (s *APIServer) upsertCertAuthority(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	var req *upsertCertAuthorityRawReq
	if err := httplib.ReadJSON(r, &req); err != nil {
		return nil, trace.Wrap(err)
	}
	ca, err := services.GetCertAuthorityMarshaler().UnmarshalCertAuthority(req.CA)
	if err != nil {
		return nil, trace.Wrap(err)
	}
	if err := auth.UpsertCertAuthority(ca, req.TTL); err != nil {
		return nil, trace.Wrap(err)
	}
	return message("ok"), nil
}

func (s *APIServer) getCertAuthorities(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	loadKeys, _, err := httplib.ParseBool(r.URL.Query(), "load_keys")
	if err != nil {
		return nil, trace.Wrap(err)
	}
	certs, err := auth.GetCertAuthorities(services.CertAuthType(p.ByName("type")), loadKeys)

	if err != nil {
		return nil, trace.Wrap(err)
	}
	items := make([]json.RawMessage, len(certs))
	for i, cert := range certs {
		data, err := services.GetCertAuthorityMarshaler().MarshalCertAuthority(cert, services.WithVersion(version))
		if err != nil {
			return nil, trace.Wrap(err)
		}
		items[i] = data
	}
	return items, nil
}

func (s *APIServer) getCertAuthority(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	loadKeys, _, err := httplib.ParseBool(r.URL.Query(), "load_keys")
	if err != nil {
		return nil, trace.Wrap(err)
	}
	id := services.CertAuthID{
		Type:       services.CertAuthType(p.ByName("type")),
		DomainName: p.ByName("domain"),
	}
	ca, err := auth.GetCertAuthority(id, loadKeys)
	if err != nil {
		return nil, trace.Wrap(err)
	}
	return rawMessage(services.GetCertAuthorityMarshaler().MarshalCertAuthority(ca, services.WithVersion(version)))
}

func (s *APIServer) getDomainName(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	domain, err := auth.GetDomainName()
	if err != nil {
		return nil, trace.Wrap(err)
	}
	return domain, nil
}

// getU2FAppID returns the U2F AppID in the auth configuration
func (s *APIServer) getU2FAppID(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	universalSecondFactor, err := auth.GetUniversalSecondFactor()
	if err != nil {
		return nil, trace.Wrap(err)
	}

	w.Header().Set("Content-Type", "application/fido.trusted-apps+json")
	return universalSecondFactor.GetAppID(), nil
}

func (s *APIServer) deleteCertAuthority(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	id := services.CertAuthID{
		DomainName: p.ByName("domain"),
		Type:       services.CertAuthType(p.ByName("type")),
	}
	if err := auth.DeleteCertAuthority(id); err != nil {
		return nil, trace.Wrap(err)
	}
	return message(fmt.Sprintf("cert '%v' deleted", id)), nil
}

type createSessionReq struct {
	Session session.Session `json:"session"`
}

func (s *APIServer) createSession(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	var req *createSessionReq
	if err := httplib.ReadJSON(r, &req); err != nil {
		return nil, trace.Wrap(err)
	}
	req.Session.Namespace = p.ByName("namespace")
	if err := auth.CreateSession(req.Session); err != nil {
		return nil, trace.Wrap(err)
	}
	return message("ok"), nil
}

type updateSessionReq struct {
	Update session.UpdateRequest `json:"update"`
}

func (s *APIServer) updateSession(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	var req *updateSessionReq
	if err := httplib.ReadJSON(r, &req); err != nil {
		return nil, trace.Wrap(err)
	}
	req.Update.Namespace = p.ByName("namespace")
	if err := auth.UpdateSession(req.Update); err != nil {
		return nil, trace.Wrap(err)
	}
	return message("ok"), nil
}

func (s *APIServer) getSessions(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	sessions, err := auth.GetSessions(p.ByName("namespace"))
	if err != nil {
		return nil, trace.Wrap(err)
	}
	return sessions, nil
}

func (s *APIServer) getSession(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	sid, err := session.ParseID(p.ByName("id"))
	if err != nil {
		return nil, trace.Wrap(err)
	}
	se, err := auth.GetSession(p.ByName("namespace"), *sid)
	if err != nil {
		return nil, trace.Wrap(err)
	}
	return se, nil
}

type getSignupTokenDataResponse struct {
	User  string `json:"user"`
	QRImg []byte `json:"qrimg"`
}

// getSignupTokenData returns the signup data for a token.
func (s *APIServer) getSignupTokenData(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	token := p.ByName("token")

	user, otpQRCode, err := auth.GetSignupTokenData(token)
	if err != nil {
		return nil, trace.Wrap(err)
	}

	return &getSignupTokenDataResponse{
		User:  user,
		QRImg: otpQRCode,
	}, nil
}

func (s *APIServer) getSignupU2FRegisterRequest(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	token := p.ByName("token")
	u2fRegReq, err := auth.GetSignupU2FRegisterRequest(token)
	if err != nil {
		return nil, trace.Wrap(err)
	}
	return u2fRegReq, nil
}

type createSignupTokenReq struct {
	User services.UserV1 `json:"user"`
}

func (s *APIServer) createSignupToken(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	var req *createSignupTokenReq

	if err := httplib.ReadJSON(r, &req); err != nil {
		return nil, trace.Wrap(err)
	}

	if err := req.User.Check(); err != nil {
		return nil, trace.Wrap(err)
	}

	token, err := auth.CreateSignupToken(req.User)
	if err != nil {
		return nil, trace.Wrap(err)
	}

	return token, nil
}

type createUserWithTokenReq struct {
	Token    string `json:"token"`
	Password string `json:"password"`
	OTPToken string `json:"otp_token"`
}

func (s *APIServer) createUserWithToken(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	var req *createUserWithTokenReq
	if err := httplib.ReadJSON(r, &req); err != nil {
		return nil, trace.Wrap(err)
	}

	cap, err := auth.GetClusterAuthPreference()
	if err != nil {
		return nil, trace.Wrap(err)
	}

	var webSession services.WebSession

	switch cap.GetSecondFactor() {
	case teleport.OFF:
		webSession, err = auth.CreateUserWithoutOTP(req.Token, req.Password)
	case teleport.OTP, teleport.TOTP, teleport.HOTP:
		webSession, err = auth.CreateUserWithOTP(req.Token, req.Password, req.OTPToken)
	}
	if err != nil {
		log.Error(trace.DebugReport(err))
		return nil, trace.Wrap(err)
	}

	return rawMessage(services.GetWebSessionMarshaler().MarshalWebSession(webSession, services.WithVersion(version)))
}

type createUserWithU2FTokenReq struct {
	Token               string               `json:"token"`
	Password            string               `json:"password"`
	U2FRegisterResponse u2f.RegisterResponse `json:"u2f_register_response"`
}

func (s *APIServer) createUserWithU2FToken(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	var req *createUserWithU2FTokenReq
	if err := httplib.ReadJSON(r, &req); err != nil {
		return nil, trace.Wrap(err)
	}

	sess, err := auth.CreateUserWithU2FToken(req.Token, req.Password, req.U2FRegisterResponse)
	if err != nil {
		log.Error(err)
		return nil, trace.Wrap(err)
	}
	return rawMessage(services.GetWebSessionMarshaler().MarshalWebSession(sess, services.WithVersion(version)))
}

type upsertOIDCConnectorRawReq struct {
	Connector json.RawMessage `json:"connector"`
	TTL       time.Duration   `json:"ttl"`
}

func (s *APIServer) upsertOIDCConnector(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	var req *upsertOIDCConnectorRawReq
	if err := httplib.ReadJSON(r, &req); err != nil {
		return nil, trace.Wrap(err)
	}
	connector, err := services.GetOIDCConnectorMarshaler().UnmarshalOIDCConnector(req.Connector)
	if err != nil {
		return nil, trace.Wrap(err)
	}
	err = auth.UpsertOIDCConnector(connector, req.TTL)
	if err != nil {
		return nil, trace.Wrap(err)
	}
	return message("ok"), nil
}

func (s *APIServer) getOIDCConnector(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	withSecrets, _, err := httplib.ParseBool(r.URL.Query(), "with_secrets")
	if err != nil {
		return nil, trace.Wrap(err)
	}
	connector, err := auth.GetOIDCConnector(p.ByName("id"), withSecrets)
	if err != nil {
		return nil, trace.Wrap(err)
	}
	return rawMessage(services.GetOIDCConnectorMarshaler().MarshalOIDCConnector(connector, services.WithVersion(version)))
}

func (s *APIServer) deleteOIDCConnector(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	err := auth.DeleteOIDCConnector(p.ByName("id"))
	if err != nil {
		return nil, trace.Wrap(err)
	}
	return message("ok"), nil
}

func (s *APIServer) getOIDCConnectors(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	withSecrets, _, err := httplib.ParseBool(r.URL.Query(), "with_secrets")
	if err != nil {
		return nil, trace.Wrap(err)
	}
	connectors, err := auth.GetOIDCConnectors(withSecrets)
	if err != nil {
		return nil, trace.Wrap(err)
	}
	items := make([]json.RawMessage, len(connectors))
	for i, connector := range connectors {
		data, err := services.GetOIDCConnectorMarshaler().MarshalOIDCConnector(connector, services.WithVersion(version))
		if err != nil {
			return nil, trace.Wrap(err)
		}
		items[i] = data
	}
	return items, nil
}

type createOIDCAuthRequestReq struct {
	Req services.OIDCAuthRequest `json:"req"`
}

func (s *APIServer) createOIDCAuthRequest(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	var req *createOIDCAuthRequestReq
	if err := httplib.ReadJSON(r, &req); err != nil {
		return nil, trace.Wrap(err)
	}
	response, err := auth.CreateOIDCAuthRequest(req.Req)
	if err != nil {
		return nil, trace.Wrap(err)
	}
	return response, nil
}

type validateOIDCAuthCallbackReq struct {
	Query url.Values `json:"query"`
}

// oidcAuthRawResponse is returned when auth server validated callback parameters
// returned from OIDC provider
type oidcAuthRawResponse struct {
	// Username is authenticated teleport username
	Username string `json:"username"`
	// Identity contains validated OIDC identity
	Identity services.OIDCIdentity `json:"identity"`
	// Web session will be generated by auth server if requested in OIDCAuthRequest
	Session json.RawMessage `json:"session,omitempty"`
	// Cert will be generated by certificate authority
	Cert []byte `json:"cert,omitempty"`
	// Req is original oidc auth request
	Req services.OIDCAuthRequest `json:"req"`
	// HostSigners is a list of signing host public keys
	// trusted by proxy, used in console login
	HostSigners []json.RawMessage `json:"host_signers"`
}

func (s *APIServer) validateOIDCAuthCallback(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	var req *validateOIDCAuthCallbackReq
	if err := httplib.ReadJSON(r, &req); err != nil {
		return nil, trace.Wrap(err)
	}
	response, err := auth.ValidateOIDCAuthCallback(req.Query)
	if err != nil {
		return nil, trace.Wrap(err)
	}
	raw := oidcAuthRawResponse{
		Username: response.Username,
		Identity: response.Identity,
		Cert:     response.Cert,
		Req:      response.Req,
	}
	if response.Session != nil {
		rawSession, err := services.GetWebSessionMarshaler().MarshalWebSession(response.Session, services.WithVersion(version))
		if err != nil {
			return nil, trace.Wrap(err)
		}
		raw.Session = rawSession
	}
	raw.HostSigners = make([]json.RawMessage, len(response.HostSigners))
	for i, ca := range response.HostSigners {
		data, err := services.GetCertAuthorityMarshaler().MarshalCertAuthority(ca, services.WithVersion(version))
		if err != nil {
			return nil, trace.Wrap(err)
		}
		raw.HostSigners[i] = data
	}
	return &raw, nil
}

// HTTP GET /:version/events?query
//
// Query fields:
//	'from'  : time filter in RFC3339 format
//	'to'    : time filter in RFC3339 format
//  ...     : other fields are passed directly to the audit backend
func (s *APIServer) searchEvents(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	var err error
	to := time.Now().In(time.UTC)
	from := to.AddDate(0, -1, 0) // one month ago
	query := r.URL.Query()
	// parse 'to' and 'from' params:
	fromStr := query.Get("from")
	if fromStr != "" {
		from, err = time.Parse(time.RFC3339, fromStr)
		if err != nil {
			return nil, trace.BadParameter("from")
		}
	}
	toStr := query.Get("to")
	if toStr != "" {
		to, err = time.Parse(time.RFC3339, toStr)
		if err != nil {
			return nil, trace.BadParameter("to")
		}
	}
	// remove 'to' & 'from' fields, passing the rest of the query unmodified
	// to whatever pluggable search is implemented by the backend
	query.Del("to")
	query.Del("from")
	eventsList, err := auth.SearchEvents(from, to, query.Encode())
	if err != nil {
		return nil, trace.Wrap(err)
	}
	return eventsList, nil
}

type auditEventReq struct {
	Type   string             `json:"type"`
	Fields events.EventFields `json:"fields"`
}

// HTTP	POST /:version/events
func (s *APIServer) emitAuditEvent(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	var req auditEventReq
	if err := httplib.ReadJSON(r, &req); err != nil {
		return nil, trace.Wrap(err)
	}
	if err := auth.EmitAuditEvent(req.Type, req.Fields); err != nil {
		return nil, trace.Wrap(err)
	}
	return message("ok"), nil
}

// HTTP POST /:version/sessions/:id/stream
func (s *APIServer) postSessionChunk(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	sid, err := session.ParseID(p.ByName("id"))
	if err != nil {
		return nil, trace.Wrap(err)
	}
	namespace := p.ByName("namespace")
	if err = auth.PostSessionChunk(namespace, *sid, r.Body); err != nil {
		return nil, trace.Wrap(err)
	}
	return message("ok"), nil
}

// HTTP GET /:version/sessions/:id/stream?offset=x&bytes=y
// Query parameters:
//   "offset"   : bytes from the beginning
//   "bytes"    : number of bytes to read (it won't return more than 512Kb)
func (s *APIServer) getSessionChunk(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	sid, err := session.ParseID(p.ByName("id"))
	if err != nil {
		return nil, trace.BadParameter("missing parameter id")
	}
	namespace := p.ByName("namespace")

	// "offset bytes" query param
	offsetBytes, err := strconv.Atoi(r.URL.Query().Get("offset"))
	if err != nil || offsetBytes < 0 {
		offsetBytes = 0
	}
	// "max bytes" query param
	max, err := strconv.Atoi(r.URL.Query().Get("bytes"))
	if err != nil || offsetBytes < 0 {
		offsetBytes = 0
	}
	log.Debugf("apiserver.GetSessionChunk(%v, %v, offset=%d)", namespace, *sid, offsetBytes)
	w.Header().Set("Content-Type", "text/plain")

	buffer, err := auth.GetSessionChunk(namespace, *sid, offsetBytes, max)
	if err != nil {
		return nil, trace.Wrap(err)
	}
	if _, err = w.Write(buffer); err != nil {
		return nil, trace.Wrap(err)
	}
	w.Header().Set("Content-Type", "application/octet-stream")
	return nil, nil
}

// HTTP GET /:version/sessions/:id/events?maxage=n
// Query:
//    'after' : cursor value to return events newer than N. Defaults to 0, (return all)
func (s *APIServer) getSessionEvents(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	sid, err := session.ParseID(p.ByName("id"))
	if err != nil {
		return nil, trace.Wrap(err)
	}
	namespace := p.ByName("namespace")
	afterN, err := strconv.Atoi(r.URL.Query().Get("after"))
	if err != nil {
		afterN = 0
	}
	return auth.GetSessionEvents(namespace, *sid, afterN)
}

type upsertNamespaceReq struct {
	Namespace services.Namespace `json:"namespace"`
}

func (s *APIServer) upsertNamespace(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	var req *upsertNamespaceReq
	if err := httplib.ReadJSON(r, &req); err != nil {
		return nil, trace.Wrap(err)
	}
	if err := auth.UpsertNamespace(req.Namespace); err != nil {
		return nil, trace.Wrap(err)
	}
	return message("ok"), nil
}

func (s *APIServer) getNamespaces(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	namespaces, err := auth.GetNamespaces()
	if err != nil {
		return nil, trace.Wrap(err)
	}
	return namespaces, nil
}

func (s *APIServer) getNamespace(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	name := p.ByName("namespace")
	namespace, err := auth.GetNamespace(name)
	if err != nil {
		return nil, trace.Wrap(err)
	}
	return namespace, nil
}

func (s *APIServer) deleteNamespace(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	name := p.ByName("namespace")
	err := auth.DeleteNamespace(name)
	if err != nil {
		return nil, trace.Wrap(err)
	}
	return message("ok"), nil
}

type upsertRoleRawReq struct {
	Role json.RawMessage `json:"role"`
}

func (s *APIServer) upsertRole(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	var req *upsertRoleRawReq
	if err := httplib.ReadJSON(r, &req); err != nil {
		return nil, trace.Wrap(err)
	}
	role, err := services.GetRoleMarshaler().UnmarshalRole(req.Role)
	if err != nil {
		return nil, trace.Wrap(err)
	}
	err = auth.UpsertRole(role)
	if err != nil {
		return nil, trace.Wrap(err)
	}
	return message(fmt.Sprintf("'%v' role upserted", role.GetName())), nil
}

func (s *APIServer) getRole(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	role, err := auth.GetRole(p.ByName("role"))
	if err != nil {
		return nil, trace.Wrap(err)
	}
	return rawMessage(services.GetRoleMarshaler().MarshalRole(role, services.WithVersion(version)))
}

func (s *APIServer) getRoles(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	roles, err := auth.GetRoles()
	if err != nil {
		return nil, trace.Wrap(err)
	}
	out := make([]json.RawMessage, len(roles))
	for i, role := range roles {
		raw, err := services.GetRoleMarshaler().MarshalRole(role, services.WithVersion(version))
		if err != nil {
			return nil, trace.Wrap(err)
		}
		out[i] = raw
	}
	return out, nil
}

func (s *APIServer) deleteRole(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	role := p.ByName("role")
	if err := auth.DeleteRole(role); err != nil {
		return nil, trace.Wrap(err)
	}
	return message(fmt.Sprintf("role '%v' deleted", role)), nil
}

func (s *APIServer) getClusterAuthPreference(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	cap, err := auth.GetClusterAuthPreference()
	if err != nil {
		return nil, trace.Wrap(err)
	}

	return rawMessage(services.GetAuthPreferenceMarshaler().Marshal(cap, services.WithVersion(version)))
}

type setClusterAuthPreferenceReq struct {
	ClusterAuthPreference json.RawMessage `json:"cluster_auth_prerference"`
}

func (s *APIServer) setClusterAuthPreference(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	var req *setClusterAuthPreferenceReq

	err := httplib.ReadJSON(r, &req)
	if err != nil {
		return nil, trace.Wrap(err)
	}

	cap, err := services.GetAuthPreferenceMarshaler().Unmarshal(req.ClusterAuthPreference)
	if err != nil {
		return nil, trace.Wrap(err)
	}

	err = auth.SetClusterAuthPreference(cap)
	if err != nil {
		return nil, trace.Wrap(err)
	}

	return message(fmt.Sprintf("cluster authenticaton preference set: %+v", cap)), nil
}

func (s *APIServer) getUniversalSecondFactor(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	universalSecondFactor, err := auth.GetUniversalSecondFactor()
	if err != nil {
		return nil, trace.Wrap(err)
	}

	return rawMessage(services.GetUniversalSecondFactorMarshaler().Marshal(universalSecondFactor, services.WithVersion(version)))
}

type setUniversalSecondFactorReq struct {
	UniversalSecondFactor json.RawMessage `json:"universal_second_factor"`
}

func (s *APIServer) setUniversalSecondFactor(auth ClientI, w http.ResponseWriter, r *http.Request, p httprouter.Params, version string) (interface{}, error) {
	var req *setUniversalSecondFactorReq

	err := httplib.ReadJSON(r, &req)
	if err != nil {
		return nil, trace.Wrap(err)
	}

	universalSecondFactor, err := services.GetUniversalSecondFactorMarshaler().Unmarshal(req.UniversalSecondFactor)
	if err != nil {
		return nil, trace.Wrap(err)
	}

	err = auth.SetUniversalSecondFactor(universalSecondFactor)
	if err != nil {
		return nil, trace.Wrap(err)
	}

	return message(fmt.Sprintf("universal second factor set: %+v", universalSecondFactor)), nil
}

func message(msg string) map[string]interface{} {
	return map[string]interface{}{"message": msg}
}