Adjust "groupfilter" to be able to search by member name

Previously the input for the LDAP Groupfilter to lookup all groups a
specific user is member of was the userpb.UserId part of the User
object. I.e. it assumed we could run a single LDAP query to get all
groups a user is member of by specifying the userid. However most
LDAP Servers store the GroupMembership by either username (e.g. in
memberUID Attribute) or by the user's DN (e.g. in member/uniqueMember).

The GetUserGroups method was already updated recently to do a two-staged
lookup (first lookup the user's name by Id then search the Groups by
username). This change just removes the userpb.UserId template processing
from the GroupFilter and replaces it with a single string (the
username) to get rid of the annoying `{{.}}` template values in the
config.

In the future we should add a config switch to also allow lookups by
member DN.

changelog/unreleased/ldap-usergroupfilter-template.md

@@ -0,0 +1,15 @@
+Change: Replace template in GroupFilter for UserProvider with a simple string
+
+Previously the "groupfilter" configuration for the UserProvider expected a
+go-template value (based of of an `userpb.UserId` as it's input). And it
+assumed we could run a single LDAP query to get all groups a user is member of
+by specifying the userid. However most LDAP Servers store the GroupMembership
+by either username (e.g. in memberUID Attribute) or by the user's DN (e.g. in
+member/uniqueMember).
+
+This change removes the userpb.UserId template processing from the groupfilter
+and replaces it with a single string (the username) to cleanup the config a
+bit. Existing configs need to be update to replace the go template references
+in `groupfilter` (e.g. `{{.}}` or `{{.OpaqueId}}`) with `{{query}}`.
+
+https://github.com/cs3org/reva/pull/2436

pkg/user/manager/ldap/ldap.go

@@ -43,9 +43,8 @@ func init() {
 }
 
 type manager struct {
-	c           *config
-	userfilter  *template.Template
-	groupfilter *template.Template
+	c          *config
+	userfilter *template.Template
 }
 
 type config struct {
@@ -124,7 +123,6 @@ func (m *manager) Configure(ml map[string]interface{}) error {
 	if c.FindFilter == "" {
 		c.FindFilter = c.UserFilter
 	}
-	c.GroupFilter = strings.ReplaceAll(c.GroupFilter, "%s", "{{.OpaqueId}}")
 
 	if c.Nobody == 0 {
 		c.Nobody = 99
@@ -136,11 +134,6 @@ func (m *manager) Configure(ml map[string]interface{}) error {
 		err := errors.Wrap(err, fmt.Sprintf("error parsing userfilter tpl:%s", c.UserFilter))
 		panic(err)
 	}
-	m.groupfilter, err = template.New("gf").Funcs(sprig.TxtFuncMap()).Parse(c.GroupFilter)
-	if err != nil {
-		err := errors.Wrap(err, fmt.Sprintf("error parsing groupfilter tpl:%s", c.GroupFilter))
-		panic(err)
-	}
 	return nil
 }
 
@@ -433,11 +426,6 @@ func (m *manager) getFindFilter(query string) string {
 	return strings.ReplaceAll(m.c.FindFilter, "{{query}}", ldap.EscapeFilter(query))
 }
 
-func (m *manager) getGroupFilter(uid interface{}) string {
-	b := bytes.Buffer{}
-	if err := m.groupfilter.Execute(&b, uid); err != nil {
-		err := errors.Wrap(err, fmt.Sprintf("error executing group template: userid:%+v", uid))
-		panic(err)
-	}
-	return b.String()
+func (m *manager) getGroupFilter(memberName string) string {
+	return strings.ReplaceAll(m.c.GroupFilter, "{{query}}", ldap.EscapeFilter(memberName))
 }

tests/oc-integration-tests/drone/ldap-users.toml

@@ -37,7 +37,7 @@ base_dn="dc=owncloud,dc=com"
 userfilter="(&(objectclass=posixAccount)(|(entryuuid={{.OpaqueId}})(cn={{.OpaqueId}})))"
 findfilter="(&(objectclass=posixAccount)(|(cn={{query}}*)(displayname={{query}}*)(mail={{query}}*)))"
 attributefilter="(&(objectclass=posixAccount)({{attr}}={{value}}))"
-groupfilter="(&(objectclass=posixGroup)(cn=*)(memberuid={{.}}))"
+groupfilter="(&(objectclass=posixGroup)(cn=*)(memberuid={{query}}))"
 bind_username="cn=admin,dc=owncloud,dc=com"
 bind_password="admin"
 idp="http://localhost:20080"

tests/oc-integration-tests/local-mesh/ldap-users.toml

@@ -38,7 +38,7 @@ base_dn="dc=owncloud,dc=com"
 userfilter="(&(objectclass=posixAccount)(|(uid={{.OpaqueId}})(cn={{.OpaqueId}})))"
 findfilter="(&(objectclass=posixAccount)(|(cn={{query}}*)(displayname={{query}}*)(mail={{query}}*)))"
 attributefilter="(&(objectclass=posixAccount)({{attr}}={{value}}))"
-groupfilter="(&(objectclass=posixGroup)(cn=*)(memberuid={{.OpaqueId}}))"
+groupfilter="(&(objectclass=posixGroup)(cn=*)(memberuid={{query}}))"
 bind_username="cn=admin,dc=owncloud,dc=com"
 bind_password="admin"
 idp="http://localhost:40080"

tests/oc-integration-tests/local/ldap-users.toml

@@ -41,7 +41,7 @@ base_dn="dc=owncloud,dc=com"
 userfilter="(&(objectclass=posixAccount)(|(entryuuid={{.OpaqueId}})(cn={{.OpaqueId}})))"
 findfilter="(&(objectclass=posixAccount)(|(cn={{query}}*)(displayname={{query}}*)(mail={{query}}*)))"
 attributefilter="(&(objectclass=posixAccount)({{attr}}={{value}}))"
-groupfilter="(&(objectclass=posixGroup)(cn=*)(memberuid={{.}}))"
+groupfilter="(&(objectclass=posixGroup)(cn=*)(memberuid={{query}}))"
 bind_username="cn=admin,dc=owncloud,dc=com"
 bind_password="admin"
 idp="http://localhost:20080"