Files
grafana/pkg/login/ldap.go
2018-04-17 14:06:25 -04:00

372 lines
9.1 KiB
Go

package login
import (
"crypto/tls"
"crypto/x509"
"errors"
"fmt"
"io/ioutil"
"strings"
"github.com/davecgh/go-spew/spew"
"github.com/go-ldap/ldap"
"github.com/grafana/grafana/pkg/bus"
"github.com/grafana/grafana/pkg/log"
m "github.com/grafana/grafana/pkg/models"
"github.com/grafana/grafana/pkg/setting"
)
type ILdapConn interface {
Bind(username, password string) error
Search(*ldap.SearchRequest) (*ldap.SearchResult, error)
StartTLS(*tls.Config) error
Close()
}
type ILdapAuther interface {
Login(query *m.LoginUserQuery) error
SyncSignedInUser(ctx *m.ReqContext, signedInUser *m.SignedInUser) error
GetGrafanaUserFor(ctx *m.ReqContext, ldapUser *LdapUserInfo) (*m.User, error)
}
type ldapAuther struct {
server *LdapServerConf
conn ILdapConn
requireSecondBind bool
log log.Logger
}
var NewLdapAuthenticator = func(server *LdapServerConf) ILdapAuther {
return &ldapAuther{server: server, log: log.New("ldap")}
}
var ldapDial = func(network, addr string) (ILdapConn, error) {
return ldap.Dial(network, addr)
}
func (a *ldapAuther) Dial() error {
var err error
var certPool *x509.CertPool
if a.server.RootCACert != "" {
certPool = x509.NewCertPool()
for _, caCertFile := range strings.Split(a.server.RootCACert, " ") {
if pem, err := ioutil.ReadFile(caCertFile); err != nil {
return err
} else {
if !certPool.AppendCertsFromPEM(pem) {
return errors.New("Failed to append CA certificate " + caCertFile)
}
}
}
}
for _, host := range strings.Split(a.server.Host, " ") {
address := fmt.Sprintf("%s:%d", host, a.server.Port)
if a.server.UseSSL {
tlsCfg := &tls.Config{
InsecureSkipVerify: a.server.SkipVerifySSL,
ServerName: host,
RootCAs: certPool,
}
if a.server.StartTLS {
a.conn, err = ldap.Dial("tcp", address)
if err == nil {
if err = a.conn.StartTLS(tlsCfg); err == nil {
return nil
}
}
} else {
a.conn, err = ldap.DialTLS("tcp", address, tlsCfg)
}
} else {
a.conn, err = ldapDial("tcp", address)
}
if err == nil {
return nil
}
}
return err
}
func (a *ldapAuther) Login(query *m.LoginUserQuery) error {
// connect to ldap server
if err := a.Dial(); err != nil {
return err
}
defer a.conn.Close()
// perform initial authentication
if err := a.initialBind(query.Username, query.Password); err != nil {
return err
}
// find user entry & attributes
ldapUser, err := a.searchForUser(query.Username)
if err != nil {
return err
}
a.log.Debug("Ldap User found", "info", spew.Sdump(ldapUser))
// check if a second user bind is needed
if a.requireSecondBind {
err = a.secondBind(ldapUser, query.Password)
if err != nil {
return err
}
}
grafanaUser, err := a.GetGrafanaUserFor(query.ReqContext, ldapUser)
if err != nil {
return err
}
query.User = grafanaUser
return nil
}
func (a *ldapAuther) SyncSignedInUser(ctx *m.ReqContext, signedInUser *m.SignedInUser) error {
err := a.Dial()
if err != nil {
return err
}
defer a.conn.Close()
err = a.serverBind()
if err != nil {
return err
}
ldapUser, err := a.searchForUser(signedInUser.Login)
if err != nil {
a.log.Error("Failed searching for user in ldap", "error", err)
return err
}
grafanaUser, err := a.GetGrafanaUserFor(ctx, ldapUser)
if err != nil {
return err
}
signedInUser.Login = grafanaUser.Login
signedInUser.Email = grafanaUser.Email
signedInUser.Name = grafanaUser.Name
return nil
}
func (a *ldapAuther) GetGrafanaUserFor(ctx *m.ReqContext, ldapUser *LdapUserInfo) (*m.User, error) {
extUser := &m.ExternalUserInfo{
AuthModule: "ldap",
AuthId: ldapUser.DN,
Name: fmt.Sprintf("%s %s", ldapUser.FirstName, ldapUser.LastName),
Login: ldapUser.Username,
Email: ldapUser.Email,
OrgRoles: map[int64]m.RoleType{},
}
for _, group := range a.server.LdapGroups {
// only use the first match for each org
if extUser.OrgRoles[group.OrgId] != "" {
continue
}
if ldapUser.isMemberOf(group.GroupDN) {
extUser.OrgRoles[group.OrgId] = group.OrgRole
}
}
// validate that the user has access
// if there are no ldap group mappings access is true
// otherwise a single group must match
if len(a.server.LdapGroups) > 0 && len(extUser.OrgRoles) < 1 {
a.log.Info(
"Ldap Auth: user does not belong in any of the specified ldap groups",
"username", ldapUser.Username,
"groups", ldapUser.MemberOf)
return nil, ErrInvalidCredentials
}
// add/update user in grafana
userQuery := &m.UpsertUserCommand{
ReqContext: ctx,
ExternalUser: extUser,
SignupAllowed: setting.LdapAllowSignup,
}
err := bus.Dispatch(userQuery)
if err != nil {
return nil, err
}
return userQuery.Result, nil
}
func (a *ldapAuther) serverBind() error {
// bind_dn and bind_password to bind
if err := a.conn.Bind(a.server.BindDN, a.server.BindPassword); err != nil {
a.log.Info("LDAP initial bind failed, %v", err)
if ldapErr, ok := err.(*ldap.Error); ok {
if ldapErr.ResultCode == 49 {
return ErrInvalidCredentials
}
}
return err
}
return nil
}
func (a *ldapAuther) secondBind(ldapUser *LdapUserInfo, userPassword string) error {
if err := a.conn.Bind(ldapUser.DN, userPassword); err != nil {
a.log.Info("Second bind failed", "error", err)
if ldapErr, ok := err.(*ldap.Error); ok {
if ldapErr.ResultCode == 49 {
return ErrInvalidCredentials
}
}
return err
}
return nil
}
func (a *ldapAuther) initialBind(username, userPassword string) error {
if a.server.BindPassword != "" || a.server.BindDN == "" {
userPassword = a.server.BindPassword
a.requireSecondBind = true
}
bindPath := a.server.BindDN
if strings.Contains(bindPath, "%s") {
bindPath = fmt.Sprintf(a.server.BindDN, username)
}
if err := a.conn.Bind(bindPath, userPassword); err != nil {
a.log.Info("Initial bind failed", "error", err)
if ldapErr, ok := err.(*ldap.Error); ok {
if ldapErr.ResultCode == 49 {
return ErrInvalidCredentials
}
}
return err
}
return nil
}
func (a *ldapAuther) searchForUser(username string) (*LdapUserInfo, error) {
var searchResult *ldap.SearchResult
var err error
for _, searchBase := range a.server.SearchBaseDNs {
searchReq := ldap.SearchRequest{
BaseDN: searchBase,
Scope: ldap.ScopeWholeSubtree,
DerefAliases: ldap.NeverDerefAliases,
Attributes: []string{
a.server.Attr.Username,
a.server.Attr.Surname,
a.server.Attr.Email,
a.server.Attr.Name,
a.server.Attr.MemberOf,
},
Filter: strings.Replace(a.server.SearchFilter, "%s", ldap.EscapeFilter(username), -1),
}
searchResult, err = a.conn.Search(&searchReq)
if err != nil {
return nil, err
}
if len(searchResult.Entries) > 0 {
break
}
}
if len(searchResult.Entries) == 0 {
return nil, ErrInvalidCredentials
}
if len(searchResult.Entries) > 1 {
return nil, errors.New("Ldap search matched more than one entry, please review your filter setting")
}
var memberOf []string
if a.server.GroupSearchFilter == "" {
memberOf = getLdapAttrArray(a.server.Attr.MemberOf, searchResult)
} else {
// If we are using a POSIX LDAP schema it won't support memberOf, so we manually search the groups
var groupSearchResult *ldap.SearchResult
for _, groupSearchBase := range a.server.GroupSearchBaseDNs {
var filter_replace string
filter_replace = getLdapAttr(a.server.GroupSearchFilterUserAttribute, searchResult)
if a.server.GroupSearchFilterUserAttribute == "" {
filter_replace = getLdapAttr(a.server.Attr.Username, searchResult)
}
filter := strings.Replace(a.server.GroupSearchFilter, "%s", ldap.EscapeFilter(filter_replace), -1)
a.log.Info("Searching for user's groups", "filter", filter)
groupSearchReq := ldap.SearchRequest{
BaseDN: groupSearchBase,
Scope: ldap.ScopeWholeSubtree,
DerefAliases: ldap.NeverDerefAliases,
Attributes: []string{
// Here MemberOf would be the thing that identifies the group, which is normally 'cn'
a.server.Attr.MemberOf,
},
Filter: filter,
}
groupSearchResult, err = a.conn.Search(&groupSearchReq)
if err != nil {
return nil, err
}
if len(groupSearchResult.Entries) > 0 {
for i := range groupSearchResult.Entries {
memberOf = append(memberOf, getLdapAttrN(a.server.Attr.MemberOf, groupSearchResult, i))
}
break
}
}
}
return &LdapUserInfo{
DN: searchResult.Entries[0].DN,
LastName: getLdapAttr(a.server.Attr.Surname, searchResult),
FirstName: getLdapAttr(a.server.Attr.Name, searchResult),
Username: getLdapAttr(a.server.Attr.Username, searchResult),
Email: getLdapAttr(a.server.Attr.Email, searchResult),
MemberOf: memberOf,
}, nil
}
func getLdapAttrN(name string, result *ldap.SearchResult, n int) string {
for _, attr := range result.Entries[n].Attributes {
if attr.Name == name {
if len(attr.Values) > 0 {
return attr.Values[0]
}
}
}
return ""
}
func getLdapAttr(name string, result *ldap.SearchResult) string {
return getLdapAttrN(name, result, 0)
}
func getLdapAttrArray(name string, result *ldap.SearchResult) []string {
for _, attr := range result.Entries[0].Attributes {
if attr.Name == name {
return attr.Values
}
}
return []string{}
}