This repository has been archived by the owner on Jul 1, 2021. It is now read-only.
/
virtual_key_store.go
177 lines (146 loc) · 4.06 KB
/
virtual_key_store.go
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
// Copyright © 2017 VMware, Inc. All Rights Reserved.
// SPDX-License-Identifier: BSD-2-Clause
package vks
import (
"encoding/json"
"github.com/vmware/virtual-security-module/config"
"github.com/vmware/virtual-security-module/crypt"
"log"
)
// An implementation of a virtual key store over a collection of key stores using Polynomial Secret Sharing.
type VirtualKeyStore struct {
keyStores []KeyStoreAdapter
keyStoreCount int
keyStoreThreshold int
secretSharer *crypt.SecretSharer
initialized bool
}
func NewVirtualKeyStore() *VirtualKeyStore {
return &VirtualKeyStore{}
}
func (vks *VirtualKeyStore) Init(cfg *config.Config) error {
vKeyStore, err := GetVirtualKeyStoreFromConfig(cfg)
if err != nil {
return err
}
vks.keyStores = vKeyStore.keyStores
vks.keyStoreCount = vKeyStore.keyStoreCount
vks.keyStoreThreshold = vKeyStore.keyStoreThreshold
vks.secretSharer = vKeyStore.secretSharer
vks.initialized = vKeyStore.initialized
return nil
}
func (vks *VirtualKeyStore) CompleteInit(*config.Config) error {
return nil
}
func (vks *VirtualKeyStore) Initialized() bool {
return vks.initialized
}
func (vks *VirtualKeyStore) Create(alias string, key []byte) error {
shares := vks.secretSharer.BreakSecret(key)
successCount := 0
var lastError error = nil
// concurrently create shares in underlying key stores
errors := make(chan error, len(shares))
for i, share := range shares {
go createShareInKeyStore(vks.keyStores[i], alias, share, errors)
}
// collect results
for i := 0; i < len(shares); i++ {
err := <-errors
if err != nil {
log.Printf("WARNING: failed to create alias %s in a key store: %v", alias, err)
lastError = err
} else {
successCount++
}
}
close(errors)
if successCount >= vks.keyStoreThreshold {
return nil
}
return lastError
}
func (vks *VirtualKeyStore) Read(alias string) ([]byte, error) {
shares := []*crypt.SecretShare{}
successCount := 0
var lastError error = nil
// concurrently read shares from underlying key stores
sharesCh := make(chan *crypt.SecretShare, vks.keyStoreCount)
errors := make(chan error, vks.keyStoreCount)
for _, ks := range vks.keyStores {
go readShareFromKeyStore(ks, alias, sharesCh, errors)
}
// collect results
for i := 0; i < vks.keyStoreCount; i++ {
err := <-errors
share := <-sharesCh
if err != nil {
log.Printf("WARNING: failed to read alias %s: %v", alias, err)
lastError = err
} else {
shares = append(shares, share)
successCount++
}
}
close(errors)
close(sharesCh)
if successCount < vks.keyStoreThreshold {
return []byte{}, lastError
}
return vks.secretSharer.ReconstructSecret(shares)
}
func (vks *VirtualKeyStore) Delete(alias string) error {
successCount := 0
var lastError error = nil
// concurrently delete shares from underlying key stores
errors := make(chan error, vks.keyStoreCount)
for _, ks := range vks.keyStores {
go deleteShareFromKeyStore(ks, alias, errors)
}
// collect results
for i := 0; i < vks.keyStoreCount; i++ {
err := <-errors
if err != nil {
log.Printf("WARNING: failed to delete alias %s: %v", alias, err)
lastError = err
} else {
successCount++
}
}
close(errors)
// we return an error iff there are enough shares left to reconstruct the key
undeletedSharesCount := vks.keyStoreCount - successCount
if undeletedSharesCount >= vks.keyStoreThreshold {
return lastError
}
return nil
}
func createShareInKeyStore(ks KeyStoreAdapter, alias string, share *crypt.SecretShare, errors chan error) {
b, err := json.Marshal(*share)
if err != nil {
errors <- err
return
}
err = ks.Create(alias, b)
errors <- err
}
func readShareFromKeyStore(ks KeyStoreAdapter, alias string, shares chan *crypt.SecretShare, errors chan error) {
b, err := ks.Read(alias)
if err != nil {
errors <- err
shares <- nil
return
}
var share crypt.SecretShare
if err := json.Unmarshal(b, &share); err != nil {
errors <- err
shares <- nil
return
}
shares <- &share
errors <- nil
}
func deleteShareFromKeyStore(ks KeyStoreAdapter, alias string, errors chan error) {
errors <- ks.Delete(alias)
}