forked from AdRoll/hologram
-
Notifications
You must be signed in to change notification settings - Fork 0
/
main.go
249 lines (209 loc) · 7.57 KB
/
main.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
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
// Copyright 2014 AdRoll, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
// Hologram auth server.
package main
import (
"crypto/tls"
"encoding/json"
"flag"
"fmt"
"io/ioutil"
"os"
"os/signal"
"syscall"
"time"
"github.com/AdRoll/hologram/log"
"github.com/AdRoll/hologram/server"
"github.com/AdRoll/hologram/transport/remote"
"github.com/aws/aws-sdk-go/aws"
"github.com/aws/aws-sdk-go/aws/session"
"github.com/aws/aws-sdk-go/service/sts"
"github.com/nmcclain/ldap"
"github.com/peterbourgon/g2s"
)
func ConnectLDAP(conf LDAP) (*ldap.Conn, error) {
var ldapServer *ldap.Conn
var err error
// Connect to the LDAP server using TLS or not depending on the config
if conf.InsecureLDAP {
log.Debug("Connecting to LDAP at server %s (NOT using TLS).", conf.Host)
ldapServer, err = ldap.Dial("tcp", conf.Host)
} else {
tlsConfig := &tls.Config{
InsecureSkipVerify: true,
}
log.Debug("Connecting to LDAP at server %s.", conf.Host)
ldapServer, err = ldap.DialTLS("tcp", conf.Host, tlsConfig)
}
if err != nil {
return nil, fmt.Errorf("Could not dial LDAP! %v", err)
}
if err = ldapServer.Bind(conf.Bind.DN, conf.Bind.Password); err != nil {
return nil, fmt.Errorf("Could not bind to LDAP! %v", err)
}
return ldapServer, nil
}
func main() {
// Parse command-line flags for this system.
var (
listenAddress = flag.String("addr", "", "Address to listen to incoming requests on.")
ldapAddress = flag.String("ldapAddr", "", "Address to connect to LDAP.")
ldapBindDN = flag.String("ldapBindDN", "", "LDAP DN to bind to for login.")
ldapInsecure = flag.Bool("insecureLDAP", false, "INSECURE: Don't use TLS for LDAP connection.")
ldapBindPassword = flag.String("ldapBindPassword", "", "LDAP password for bind.")
statsdHost = flag.String("statsHost", "", "Address to send statsd metrics to.")
iamAccount = flag.String("iamaccount", "", "AWS Account ID for generating IAM Role ARNs")
enableLDAPRoles = flag.Bool("ldaproles", false, "Enable role support using LDAP directory.")
roleAttribute = flag.String("roleattribute", "", "Group attribute to get role from.")
defaultRoleAttr = flag.String("defaultroleattr", "", "User attribute to check to determine a user's default role.")
defaultRole = flag.String("role", "", "AWS role to assume by default.")
configFile = flag.String("conf", "/etc/hologram/server.json", "Config file to load.")
cacheTimeout = flag.Int("cachetime", 3600, "Time in seconds after which to refresh LDAP user cache.")
debugMode = flag.Bool("debug", false, "Enable debug mode.")
config Config
)
flag.Parse()
// Enable debug log output if the user requested it.
if *debugMode {
log.DebugMode(true)
log.Debug("Enabling debug log output. Use sparingly.")
}
// Parse in options from the given config file.
log.Debug("Loading configuration from %s", *configFile)
configContents, configErr := ioutil.ReadFile(*configFile)
if configErr != nil {
log.Errorf("Could not read from config file. The error was: %s", configErr.Error())
os.Exit(1)
}
configParseErr := json.Unmarshal(configContents, &config)
if configParseErr != nil {
log.Errorf("Error in parsing config file: %s", configParseErr.Error())
os.Exit(1)
}
// Merge in command flag options.
if *ldapAddress != "" {
config.LDAP.Host = *ldapAddress
}
if *ldapInsecure {
config.LDAP.InsecureLDAP = true
}
if *ldapBindDN != "" {
config.LDAP.Bind.DN = *ldapBindDN
}
if *ldapBindPassword != "" {
config.LDAP.Bind.Password = *ldapBindPassword
}
if *statsdHost != "" {
config.Stats = *statsdHost
}
if *iamAccount != "" {
config.AWS.Account = *iamAccount
}
if *listenAddress != "" {
config.Listen = *listenAddress
}
if *defaultRole != "" {
config.AWS.DefaultRole = *defaultRole
}
if *enableLDAPRoles {
config.LDAP.EnableLDAPRoles = true
}
if *defaultRoleAttr != "" {
config.LDAP.DefaultRoleAttr = *defaultRoleAttr
}
if *roleAttribute != "" {
config.LDAP.RoleAttribute = *roleAttribute
}
if *cacheTimeout != 3600 {
config.CacheTimeout = *cacheTimeout
}
var stats g2s.Statter
var statsErr error
if config.LDAP.UserAttr == "" {
config.LDAP.UserAttr = "cn"
}
if config.Stats == "" {
log.Debug("No statsd server specified; no metrics will be emitted by this program.")
stats = g2s.Noop()
} else {
stats, statsErr = g2s.Dial("udp", config.Stats)
if statsErr != nil {
log.Errorf("Error connecting to statsd: %s. No metrics will be emitted by this program.", statsErr.Error())
stats = g2s.Noop()
} else {
log.Debug("This program will emit metrics to %s", config.Stats)
}
}
// Setup the server state machine that responds to requests.
stsConnection := sts.New(session.New(&aws.Config{}))
credentialsService := server.NewDirectSessionTokenService(config.AWS.Account, stsConnection, &config.AccountAliases)
open := func() (server.LDAPImplementation, error) { return ConnectLDAP(config.LDAP) }
ldapServer, err := server.NewPersistentLDAP(open)
if err != nil {
log.Errorf("Fatal error, exiting: %s", err.Error())
os.Exit(1)
}
ldapCache, err := server.NewLDAPUserCache(ldapServer, stats, config.LDAP.UserAttr, config.LDAP.BaseDN,
config.LDAP.EnableLDAPRoles, config.LDAP.RoleAttribute, config.AWS.DefaultRole, config.LDAP.DefaultRoleAttr)
if err != nil {
log.Errorf("Top-level error in LDAPUserCache layer: %s", err.Error())
os.Exit(1)
}
serverHandler := server.New(ldapCache, credentialsService, config.AWS.DefaultRole, stats, ldapServer,
config.LDAP.UserAttr, config.LDAP.BaseDN, config.LDAP.EnableLDAPRoles, config.LDAP.DefaultRoleAttr)
server, err := remote.NewServer(config.Listen, serverHandler.HandleConnection)
// Wait for a signal from the OS to shutdown.
terminate := make(chan os.Signal, 1)
signal.Notify(terminate, syscall.SIGINT, syscall.SIGTERM)
done := make(chan bool)
// SIGUSR1 and SIGUSR2 should make Hologram enable and disable debug logging, respectively.
debugEnable := make(chan os.Signal, 1)
debugDisable := make(chan os.Signal, 1)
signal.Notify(debugEnable, syscall.SIGUSR1)
signal.Notify(debugDisable, syscall.SIGUSR2)
// SIGHUP should make Hologram server reload its cache of user information from LDAP.
reloadCacheSigHup := make(chan os.Signal, 1)
signal.Notify(reloadCacheSigHup, syscall.SIGHUP)
// Reload the cache based on time set in configuration
cacheTimeoutTicker := time.NewTicker(time.Duration(config.CacheTimeout) * time.Second)
log.Info("Hologram server is online, waiting for termination.")
// Handle termination
go func() {
s := <-terminate
log.Info("Signal received by termination handler: %+v", s)
done <- true
}()
// Handle dynamic settings changes
go func() {
for {
select {
case <-debugEnable:
log.Info("Enabling debug mode.")
log.DebugMode(true)
case <-debugDisable:
log.Info("Disabling debug mode.")
log.DebugMode(false)
case <-reloadCacheSigHup:
log.Info("Force-reloading user cache.")
ldapCache.Update()
case <-cacheTimeoutTicker.C:
log.Info("Cache timeout. Reloading user cache.")
ldapCache.Update()
}
}
}()
<-done
log.Info("Caught signal; shutting down now.")
server.Close()
}