fix: disallow newer policies, users & groups with space characters (#14845)

space characters at the beginning or at the end can lead to
confusion under various UI elements in differentiating the
actual name of "policy, user or group" - to avoid this behavior
this PR onwards we shall reject such inputs for newer entries.

existing saved entries will behave as is and are going to be
operable until they are removed/renamed to something more
meaningful.

cmd/admin-handlers-users.go

@@ -241,6 +241,15 @@ func (a adminAPIHandlers) UpdateGroupMembers(w http.ResponseWriter, r *http.Requ
 	if updReq.IsRemove {
 		err = globalIAMSys.RemoveUsersFromGroup(ctx, updReq.Group, updReq.Members)
 	} else {
+		// Check if group already exists
+		if _, gerr := globalIAMSys.GetGroupDescription(updReq.Group); gerr != nil {
+			// If group does not exist, then check if the group has beginning and end space characters
+			// we will reject such group names.
+			if errors.Is(gerr, errNoSuchGroup) && hasSpaceBE(updReq.Group) {
+				writeErrorResponseJSON(ctx, w, errorCodes.ToAPIErr(ErrAdminResourceInvalidArgument), r.URL)
+				return
+			}
+		}
 		err = globalIAMSys.AddUsersToGroup(ctx, updReq.Group, updReq.Members)
 	}
 	if err != nil {
@@ -442,6 +451,12 @@ func (a adminAPIHandlers) AddUser(w http.ResponseWriter, r *http.Request) {
 		return
 	}
 
+	// Check if accessKey has beginning and end space characters, this only applies to new users.
+	if !exists && hasSpaceBE(accessKey) {
+		writeErrorResponseJSON(ctx, w, errorCodes.ToAPIErr(ErrAdminResourceInvalidArgument), r.URL)
+		return
+	}
+
 	checkDenyOnly := false
 	if accessKey == cred.AccessKey {
 		// Check that there is no explicit deny - otherwise it's allowed
@@ -533,6 +548,12 @@ func (a adminAPIHandlers) AddServiceAccount(w http.ResponseWriter, r *http.Reque
 		return
 	}
 
+	// service account access key cannot have space characters beginning and end of the string.
+	if hasSpaceBE(createReq.AccessKey) {
+		writeErrorResponseJSON(ctx, w, errorCodes.ToAPIErr(ErrAdminResourceInvalidArgument), r.URL)
+		return
+	}
+
 	var (
 		targetUser   string
 		targetGroups []string
@@ -1384,6 +1405,12 @@ func (a adminAPIHandlers) AddCannedPolicy(w http.ResponseWriter, r *http.Request
 	vars := mux.Vars(r)
 	policyName := vars["name"]
 
+	// Policy has space characters in begin and end reject such inputs.
+	if hasSpaceBE(policyName) {
+		writeErrorResponseJSON(ctx, w, errorCodes.ToAPIErr(ErrAdminResourceInvalidArgument), r.URL)
+		return
+	}
+
 	// Error out if Content-Length is missing.
 	if r.ContentLength <= 0 {
 		writeErrorResponseJSON(ctx, w, errorCodes.ToAPIErr(ErrMissingContentLength), r.URL)

cmd/api-errors.go

@@ -383,6 +383,7 @@ const (
 	ErrAdminProfilerNotEnabled
 	ErrInvalidDecompressedSize
 	ErrAddUserInvalidArgument
+	ErrAdminResourceInvalidArgument
 	ErrAdminAccountNotEligible
 	ErrAccountNotEligible
 	ErrAdminServiceAccountNotFound
@@ -1825,6 +1826,11 @@ var errorCodes = errorCodeMap{
 		Description:    "User is not allowed to be same as admin access key",
 		HTTPStatusCode: http.StatusForbidden,
 	},
+	ErrAdminResourceInvalidArgument: {
+		Code:           "XMinioInvalidResource",
+		Description:    "Policy, user or group names are not allowed to begin or end with space characters",
+		HTTPStatusCode: http.StatusBadRequest,
+	},
 	ErrAdminAccountNotEligible: {
 		Code:           "XMinioInvalidIAMCredentials",
 		Description:    "The administrator key is not eligible for this operation",

cmd/iam-store.go

@@ -158,8 +158,7 @@ type MappedPolicy struct {
 func (mp MappedPolicy) toSlice() []string {
 	var policies []string
 	for _, policy := range strings.Split(mp.Policies, ",") {
-		policy = strings.TrimSpace(policy)
+		if strings.TrimSpace(policy) == "" {
-		if policy == "" {
 			continue
 		}
 		policies = append(policies, policy)

cmd/utils.go

@@ -88,6 +88,14 @@ func IsErr(err error, errs ...error) bool {
 	return false
 }
 
+// returns 'true' if either string has space in the
+// - beginning of a string
+// OR
+// - end of a string
+func hasSpaceBE(s string) bool {
+	return strings.TrimSpace(s) != s
+}
+
 func request2BucketObjectName(r *http.Request) (bucketName, objectName string) {
 	path, err := getResource(r.URL.Path, r.Host, globalDomainNames)
 	if err != nil {