open-vault/vault/policy_store.go

153 lines
3.5 KiB
Go

package vault
import (
"fmt"
"github.com/hashicorp/golang-lru"
"github.com/hashicorp/vault/logical"
)
const (
// policySubPath is the sub-path used for the policy store
// view. This is nested under the system view.
policySubPath = "policy/"
// policyCacheSize is the number of policies that are kept cached
policyCacheSize = 1024
)
// PolicyStore is used to provide durable storage of policy, and to
// manage ACLs associated with them.
type PolicyStore struct {
view *BarrierView
lru *lru.Cache
}
// NewPolicyStore creates a new PolicyStore that is backed
// using a given view. It used used to durable store and manage named policy.
func NewPolicyStore(view *BarrierView) *PolicyStore {
cache, _ := lru.New(policyCacheSize)
p := &PolicyStore{
view: view,
lru: cache,
}
return p
}
// setupPolicyStore is used to initialize the policy store
// when the vault is being unsealed.
func (c *Core) setupPolicyStore() error {
// Create a sub-view
view := c.systemView.SubView(policySubPath)
// Create the policy store
c.policy = NewPolicyStore(view)
return nil
}
// teardownPolicyStore is used to reverse setupPolicyStore
// when the vault is being sealed.
func (c *Core) teardownPolicyStore() error {
c.policy = nil
return nil
}
// SetPolicy is used to create or update the given policy
func (ps *PolicyStore) SetPolicy(p *Policy) error {
if p.Name == "root" {
return fmt.Errorf("cannot update root policy")
}
if p.Name == "" {
return fmt.Errorf("policy name missing")
}
entry := &logical.StorageEntry{
Key: p.Name,
Value: []byte(p.Raw),
}
if err := ps.view.Put(entry); err != nil {
return fmt.Errorf("failed to persist policy: %v", err)
}
// Update the LRU cache
ps.lru.Add(p.Name, p)
return nil
}
// GetPolicy is used to fetch the named policy
func (ps *PolicyStore) GetPolicy(name string) (*Policy, error) {
// Check for cached policy
if raw, ok := ps.lru.Get(name); ok {
return raw.(*Policy), nil
}
// Special case the root policy
if name == "root" {
p := &Policy{Name: "root"}
ps.lru.Add(p.Name, p)
return p, nil
}
// Load the policy in
out, err := ps.view.Get(name)
if err != nil {
return nil, fmt.Errorf("failed to read policy: %v", err)
}
if out == nil {
return nil, nil
}
// Parse into a policy object
p, err := Parse(string(out.Value))
if err != nil {
return nil, fmt.Errorf("failed to parse policy: %v", err)
}
p.Name = name
// Update the LRU cache
ps.lru.Add(p.Name, p)
return p, nil
}
// ListPolicies is used to list the available policies
func (ps *PolicyStore) ListPolicies() ([]string, error) {
// Scan the view, since the policy names are the same as the
// key names.
return CollectKeys(ps.view)
}
// DeletePolicy is used to delete the named policy
func (ps *PolicyStore) DeletePolicy(name string) error {
if name == "root" {
return fmt.Errorf("cannot delete root policy")
}
if err := ps.view.Delete(name); err != nil {
return fmt.Errorf("failed to delete policy: %v", err)
}
// Clear the cache
ps.lru.Remove(name)
return nil
}
// ACL is used to return an ACL which is built using the
// named policies.
func (ps *PolicyStore) ACL(names ...string) (*ACL, error) {
// Fetch the policies
var policy []*Policy
for _, name := range names {
p, err := ps.GetPolicy(name)
if err != nil {
return nil, fmt.Errorf("failed to get policy '%s': %v", name, err)
}
policy = append(policy, p)
}
// Construct the ACL
acl, err := NewACL(policy)
if err != nil {
return nil, fmt.Errorf("failed to construct ACL: %v", err)
}
return acl, nil
}