forked from hashicorp/vault
-
Notifications
You must be signed in to change notification settings - Fork 1
/
backend.go
197 lines (173 loc) · 4.84 KB
/
backend.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
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
package ldap
import (
"fmt"
"github.com/go-ldap/ldap"
"github.com/hashicorp/vault/helper/mfa"
"github.com/hashicorp/vault/logical"
"github.com/hashicorp/vault/logical/framework"
)
func Factory(conf *logical.BackendConfig) (logical.Backend, error) {
return Backend().Setup(conf)
}
func Backend() *framework.Backend {
var b backend
b.Backend = &framework.Backend{
Help: backendHelp,
PathsSpecial: &logical.Paths{
Root: append([]string{
"config",
"groups/*",
"users/*",
},
mfa.MFARootPaths()...,
),
Unauthenticated: []string{
"login/*",
},
},
Paths: append([]*framework.Path{
pathConfig(&b),
pathGroups(&b),
pathUsers(&b),
},
mfa.MFAPaths(b.Backend, pathLogin(&b))...,
),
AuthRenew: b.pathLoginRenew,
}
return b.Backend
}
type backend struct {
*framework.Backend
}
func EscapeLDAPValue(input string) string {
// RFC4514 forbids un-escaped:
// - leading space or hash
// - trailing space
// - special characters '"', '+', ',', ';', '<', '>', '\\'
// - null
for i := 0; i < len(input); i++ {
escaped := false
if input[i] == '\\' {
i++
escaped = true
}
switch input[i] {
case '"', '+', ',', ';', '<', '>', '\\':
if !escaped {
input = input[0:i] + "\\" + input[i:]
i++
}
continue
}
if escaped {
input = input[0:i] + "\\" + input[i:]
i++
}
}
if input[0] == ' ' || input[0] == '#' {
input = "\\" + input
}
if input[len(input)-1] == ' ' {
input = input[0:len(input)-1] + "\\ "
}
return input
}
func (b *backend) Login(req *logical.Request, username string, password string) ([]string, *logical.Response, error) {
cfg, err := b.Config(req)
if err != nil {
return nil, nil, err
}
if cfg == nil {
return nil, logical.ErrorResponse("ldap backend not configured"), nil
}
c, err := cfg.DialLDAP()
if err != nil {
return nil, logical.ErrorResponse(err.Error()), nil
}
binddn := ""
if cfg.DiscoverDN || (cfg.BindDN != "" && cfg.BindPassword != "") {
if err = c.Bind(cfg.BindDN, cfg.BindPassword); err != nil {
return nil, logical.ErrorResponse(fmt.Sprintf("LDAP bind (service) failed: %v", err)), nil
}
sresult, err := c.Search(&ldap.SearchRequest{
BaseDN: cfg.UserDN,
Scope: 2, // subtree
Filter: fmt.Sprintf("(%s=%s)", cfg.UserAttr, EscapeLDAPValue(username)),
})
if err != nil {
return nil, logical.ErrorResponse(fmt.Sprintf("LDAP search for binddn failed: %v", err)), nil
}
if len(sresult.Entries) != 1 {
return nil, logical.ErrorResponse("LDAP search for binddn 0 or not uniq"), nil
}
binddn = sresult.Entries[0].DN
} else {
if cfg.UPNDomain != "" {
binddn = fmt.Sprintf("%s@%s", EscapeLDAPValue(username), cfg.UPNDomain)
} else {
binddn = fmt.Sprintf("%s=%s,%s", cfg.UserAttr, EscapeLDAPValue(username), cfg.UserDN)
}
}
if err = c.Bind(binddn, password); err != nil {
return nil, logical.ErrorResponse(fmt.Sprintf("LDAP bind failed: %v", err)), nil
}
userdn := ""
if cfg.UPNDomain != "" {
// Find the distinguished name for the user if userPrincipalName used for login
sresult, err := c.Search(&ldap.SearchRequest{
BaseDN: cfg.UserDN,
Scope: 2, // subtree
Filter: fmt.Sprintf("(userPrincipalName=%s)", binddn),
})
if err != nil {
return nil, logical.ErrorResponse(fmt.Sprintf("LDAP search failed: %v", err)), nil
}
for _, e := range sresult.Entries {
userdn = e.DN
}
} else {
userdn = binddn
}
// Enumerate all groups the user is member of. The search filter should
// work with both openldap and MS AD standard schemas.
sresult, err := c.Search(&ldap.SearchRequest{
BaseDN: cfg.GroupDN,
Scope: 2, // subtree
Filter: fmt.Sprintf("(|(memberUid=%s)(member=%s)(uniqueMember=%s))", username, userdn, userdn),
})
if err != nil {
return nil, logical.ErrorResponse(fmt.Sprintf("LDAP search failed: %v", err)), nil
}
var allgroups []string
var policies []string
user, err := b.User(req.Storage, username)
if err == nil && user != nil {
allgroups = append(allgroups, user.Groups...)
}
for _, e := range sresult.Entries {
dn, err := ldap.ParseDN(e.DN)
if err != nil || len(dn.RDNs) == 0 || len(dn.RDNs[0].Attributes) == 0 {
continue
}
gname := dn.RDNs[0].Attributes[0].Value
allgroups = append(allgroups, gname)
}
for _, gname := range allgroups {
group, err := b.Group(req.Storage, gname)
if err == nil && group != nil {
policies = append(policies, group.Policies...)
}
}
if len(policies) == 0 {
return nil, logical.ErrorResponse("user is not member of any authorized group"), nil
}
return policies, nil, nil
}
const backendHelp = `
The "ldap" credential provider allows authentication querying
a LDAP server, checking username and password, and associating groups
to set of policies.
Configuration of the server is done through the "config" and "groups"
endpoints by a user with root access. Authentication is then done
by suppying the two fields for "login".
`