ldap: fixes #14432. Fix for IPA v4.6.4

IPA v4.6.4 introduced a fix that does not allow empty attributes
to be sent in a search request. This fix only adds attributes to
the request if they are mapped in the ldap toml file.

pkg/login/ldap.go

@@ -278,18 +278,27 @@ func (a *ldapAuther) searchForUser(username string) (*LdapUserInfo, error) {
 	var err error
 
 	for _, searchBase := range a.server.SearchBaseDNs {
+		attributes := make([]string, 0)
+
+		appendIfNotEmpty := func(slice []string, attr string) []string {
+			if attr == "" {
+				return slice
+			}
+			return append(slice, attr)
+		}
+
+		attributes = appendIfNotEmpty(attributes, a.server.Attr.Username)
+		attributes = appendIfNotEmpty(attributes, a.server.Attr.Surname)
+		attributes = appendIfNotEmpty(attributes, a.server.Attr.Email)
+		attributes = appendIfNotEmpty(attributes, a.server.Attr.Name)
+		attributes = appendIfNotEmpty(attributes, a.server.Attr.MemberOf)
+
 		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),
+			Attributes:   attributes,
+			Filter:       strings.Replace(a.server.SearchFilter, "%s", ldap.EscapeFilter(username), -1),
 		}
 
 		a.log.Debug("Ldap Search For User Request", "info", spew.Sdump(searchReq))

pkg/login/ldap_test.go

@@ -6,6 +6,7 @@ import (
 	"testing"
 
 	"github.com/grafana/grafana/pkg/bus"
+	"github.com/grafana/grafana/pkg/log"
 	m "github.com/grafana/grafana/pkg/models"
 	. "github.com/smartystreets/goconvey/convey"
 	"gopkg.in/ldap.v3"
@@ -322,11 +323,51 @@ func TestLdapAuther(t *testing.T) {
 			So(sc.addOrgUserCmd.Role, ShouldEqual, "Admin")
 		})
 	})
+
+	Convey("When searching for a user and not all five attributes are mapped", t, func() {
+		mockLdapConnection := &mockLdapConn{}
+		entry := ldap.Entry{
+			DN: "dn", Attributes: []*ldap.EntryAttribute{
+				{Name: "username", Values: []string{"roelgerrits"}},
+				{Name: "surname", Values: []string{"Gerrits"}},
+				{Name: "email", Values: []string{"roel@test.com"}},
+				{Name: "name", Values: []string{"Roel"}},
+				{Name: "memberof", Values: []string{"admins"}},
+			}}
+		result := ldap.SearchResult{Entries: []*ldap.Entry{&entry}}
+		mockLdapConnection.setSearchResult(&result)
+
+		// Set up attribute map without surname and email
+		ldapAuther := &ldapAuther{
+			server: &LdapServerConf{
+				Attr: LdapAttributeMap{
+					Username: "username",
+					Name:     "name",
+					MemberOf: "memberof",
+				},
+				SearchBaseDNs: []string{"BaseDNHere"},
+			},
+			conn: mockLdapConnection,
+			log:  log.New("test-logger"),
+		}
+
+		searchResult, err := ldapAuther.searchForUser("roelgerrits")
+
+		So(err, ShouldBeNil)
+		So(searchResult, ShouldNotBeNil)
+
+		// User should be searched in ldap
+		So(mockLdapConnection.searchCalled, ShouldBeTrue)
+
+		// No empty attributes should be added to the search request
+		So(len(mockLdapConnection.searchAttributes), ShouldEqual, 3)
+	})
 }
 
 type mockLdapConn struct {
-	result       *ldap.SearchResult
-	searchCalled bool
+	result           *ldap.SearchResult
+	searchCalled     bool
+	searchAttributes []string
 }
 
 func (c *mockLdapConn) Bind(username, password string) error {
@@ -339,8 +380,9 @@ func (c *mockLdapConn) setSearchResult(result *ldap.SearchResult) {
 	c.result = result
 }
 
-func (c *mockLdapConn) Search(*ldap.SearchRequest) (*ldap.SearchResult, error) {
+func (c *mockLdapConn) Search(sr *ldap.SearchRequest) (*ldap.SearchResult, error) {
 	c.searchCalled = true
+	c.searchAttributes = sr.Attributes
 	return c.result, nil
 }