Files
nomad/drivers/shared/validators/validators.go
2024-10-28 18:59:51 +01:00

138 lines
3.3 KiB
Go

// Copyright (c) HashiCorp, Inc.
// SPDX-License-Identifier: MPL-2.0
package validators
import (
"fmt"
"os/user"
"github.com/hashicorp/go-hclog"
"github.com/hashicorp/nomad/client/lib/idset"
"github.com/hashicorp/nomad/client/lib/numalib/hw"
)
type validator struct {
// DeniedHostUids configures which host uids are disallowed
deniedUIDs *idset.Set[hw.UserID]
// DeniedHostGids configures which host gids are disallowed
deniedGIDs *idset.Set[hw.GroupID]
// logger will log to the Nomad agent
logger hclog.Logger
}
// IDRange defines a range of uids or gids (to eventually restrict)
type IDRange struct {
Lower uint64 `codec:"from"`
Upper uint64 `codec:"to"`
}
func NewValidator(logger hclog.Logger, deniedHostUIDs, deniedHostGIDs string) (*validator, error) {
// TODO: Validate set, idset assumes its valid
dHostUID := idset.Parse[hw.UserID](deniedHostUIDs)
dHostGID := idset.Parse[hw.GroupID](deniedHostGIDs)
v := &validator{
deniedUIDs: dHostUID,
deniedGIDs: dHostGID,
logger: logger,
}
return v, nil
}
// HasValidIds is used when running a task to ensure the
// given user is in the ID range defined in the task config
func (v *validator) HasValidIDs(user *user.User) error {
uid, err := getUserID(user)
if err != nil {
return fmt.Errorf("validator: %w", err)
}
// check uids
if v.deniedUIDs.Contains(uid) {
return fmt.Errorf("running as uid %d is disallowed", uid)
}
gids, err := getGroupID(user)
if err != nil {
return fmt.Errorf("validator: %w", err)
}
// check gids
for _, gid := range gids {
if v.deniedGIDs.Contains(gid) {
return fmt.Errorf("running as gid %d is disallowed", gid)
}
}
return nil
}
/* // ParseIdRange is used to ensure that the configuration for ID ranges is valid.
func ParseIdRange(rangeType string, deniedRanges string) ([]IDRange, error) {
var idRanges []IDRange
parts := strings.Split(deniedRanges, ",")
// exit early if empty string
if len(parts) == 1 && parts[0] == "" {
return idRanges, nil
}
for _, rangeStr := range parts {
idRange, err := parseRangeString(rangeStr)
if err != nil {
return nil, fmt.Errorf("invalid %s: %w", rangeType, err)
}
idRanges = append(idRanges, *idRange)
}
return idRanges, nil
}
func parseRangeString(boundsString string) (*IDRange, error) {
uidDenyRangeParts := strings.Split(boundsString, "-")
var idRange IDRange
switch len(uidDenyRangeParts) {
case 0:
return nil, fmt.Errorf("range value cannot be empty")
case 1:
disallowedIdStr := uidDenyRangeParts[0]
disallowedIdInt, err := strconv.ParseUint(disallowedIdStr, 10, 32)
if err != nil {
return nil, fmt.Errorf("range bound not valid, invalid bound: %q ", disallowedIdInt)
}
idRange.Lower = disallowedIdInt
idRange.Upper = disallowedIdInt
case 2:
lowerBoundStr := uidDenyRangeParts[0]
upperBoundStr := uidDenyRangeParts[1]
lowerBoundInt, err := strconv.ParseUint(lowerBoundStr, 10, 32)
if err != nil {
return nil, fmt.Errorf("invalid bound: %q", lowerBoundStr)
}
upperBoundInt, err := strconv.ParseUint(upperBoundStr, 10, 32)
if err != nil {
return nil, fmt.Errorf("invalid bound: %q", upperBoundStr)
}
if lowerBoundInt > upperBoundInt {
return nil, fmt.Errorf("invalid range %q, lower bound cannot be greater than upper bound", boundsString)
}
idRange.Lower = lowerBoundInt
idRange.Upper = upperBoundInt
}
return &idRange, nil
}
*/