forked from google/certificate-transparency-go
-
Notifications
You must be signed in to change notification settings - Fork 0
/
distributor.go
393 lines (350 loc) · 13.2 KB
/
distributor.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
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
// Copyright 2019 Google LLC. All Rights Reserved.
//
// 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.
package submission
import (
"context"
"fmt"
"net/http"
"net/url"
"strconv"
"sync"
"time"
"github.com/golang/glog"
"github.com/ctylim/certificate-transparency-go-p192/client"
"github.com/ctylim/certificate-transparency-go-p192/ctpolicy"
"github.com/ctylim/certificate-transparency-go-p192/jsonclient"
"github.com/ctylim/certificate-transparency-go-p192/loglist2"
"github.com/ctylim/certificate-transparency-go-p192/trillian/ctfe"
"github.com/ctylim/certificate-transparency-go-p192/x509"
"github.com/google/trillian/monitoring"
ct "github.com/ctylim/certificate-transparency-go-p192"
)
var (
// Metrics are per-log, per-endpoint and some per-response-status code.
distOnce sync.Once
reqsCounter monitoring.Counter // logurl, ep => value
rspsCounter monitoring.Counter // logurl, ep, sc => value
errCounter monitoring.Counter // logurl, ep, status => value
logRspLatency monitoring.Histogram // logurl, ep => value
// Per-log
lastGetRootsSuccess monitoring.Gauge // Unix time
)
// distInitMetrics initializes all the exported metrics.
func distInitMetrics(mf monitoring.MetricFactory) {
reqsCounter = mf.NewCounter("http_reqs", "Number of requests", "logurl", "ep")
rspsCounter = mf.NewCounter("http_rsps", "Number of responses", "logurl", "ep", "httpstatus")
errCounter = mf.NewCounter("err_count", "Number of errors", "logurl", "ep", "errtype")
logRspLatency = mf.NewHistogram("http_log_latency", "Latency of responses in seconds", "logurl", "ep")
lastGetRootsSuccess = mf.NewGauge("last_get_roots_success", "Unix timestamp for last successful get-roots request", "logurl")
}
const (
// GetRootsTimeout timeout used for external requests within root-updates.
getRootsTimeout = time.Second * 10
)
// pendingLogsPolicy is policy stub used for spreading submissions across
// Pending and Qualified Logs.
type pendingLogsPolicy struct {
}
func (stubP pendingLogsPolicy) LogsByGroup(cert *x509.Certificate, approved *loglist2.LogList) (ctpolicy.LogPolicyData, error) {
baseGroup, err := ctpolicy.BaseGroupFor(approved, 1)
groups := ctpolicy.LogPolicyData{baseGroup.Name: baseGroup}
return groups, err
}
func (stubP pendingLogsPolicy) Name() string {
return "Pending/Qualified Policy"
}
// Distributor operates policy-based submission across Logs.
type Distributor struct {
ll *loglist2.LogList
usableLl *loglist2.LogList
pendingQualifiedLl *loglist2.LogList
mu sync.RWMutex
// helper structs produced out of ll during init.
logClients map[string]client.AddLogClient
logRoots loglist2.LogRoots
rootPool *ctfe.PEMCertPool
rootDataFull bool
policy ctpolicy.CTPolicy
pendingLogsPolicy ctpolicy.CTPolicy
}
// RefreshRoots requests roots from Logs and updates local copy.
// Returns error map keyed by log-URL for any Log experiencing roots retrieval
// problems
// If at least one root was successfully parsed for a log, log roots set gets
// the update.
func (d *Distributor) RefreshRoots(ctx context.Context) map[string]error {
type RootsResult struct {
LogURL string
Roots *ctfe.PEMCertPool
Err error
}
ch := make(chan RootsResult, len(d.logClients))
rctx, cancel := context.WithTimeout(ctx, getRootsTimeout)
defer cancel()
for logURL, lc := range d.logClients {
go func(logURL string, lc client.AddLogClient) {
res := RootsResult{LogURL: logURL}
roots, err := lc.GetAcceptedRoots(rctx)
if err != nil {
res.Err = fmt.Errorf("roots refresh for %s: couldn't collect roots. %s", logURL, err)
ch <- res
return
}
res.Roots = ctfe.NewPEMCertPool()
for _, r := range roots {
parsed, err := x509.ParseCertificate(r.Data)
if x509.IsFatal(err) {
errS := fmt.Errorf("roots refresh for %s: unable to parse root cert: %s", logURL, err)
if res.Err != nil {
res.Err = fmt.Errorf("%s\n%s", res.Err, errS)
} else {
res.Err = errS
}
continue
}
res.Roots.AddCert(parsed)
}
ch <- res
}(logURL, lc)
}
// Collect get-roots results for every Log-client.
freshRoots := make(loglist2.LogRoots)
errors := make(map[string]error)
for range d.logClients {
r := <-ch
// update roots
if r.Err != nil {
errors[r.LogURL] = r.Err
}
// Roots get update even if some returned roots couldn't get parsed.
if r.Roots != nil {
freshRoots[r.LogURL] = r.Roots
lastGetRootsSuccess.Set(float64(time.Now().Unix()), r.LogURL)
}
}
d.mu.Lock()
defer d.mu.Unlock()
d.logRoots = freshRoots
d.rootDataFull = len(d.logRoots) == len(d.logClients)
// Merge individual root-pools into a unified one
d.rootPool = ctfe.NewPEMCertPool()
for _, pool := range d.logRoots {
for _, c := range pool.RawCertificates() {
d.rootPool.AddCert(c)
}
}
return errors
}
// incRspsCounter extracts HTTP status code and increments corresponding rspsCounter.
func incRspsCounter(logURL string, endpoint string, rspErr error) {
status := http.StatusOK
if rspErr != nil {
status = http.StatusBadRequest // default to this if status code unavailable
if err, ok := rspErr.(client.RspError); ok {
status = err.StatusCode
}
}
rspsCounter.Inc(logURL, endpoint, strconv.Itoa(status))
}
// incErrCounter increments corresponding errCounter if any error occurred during
// submission to a Log.
func incErrCounter(logURL string, endpoint string, rspErr error) {
if rspErr == nil {
return
}
err, ok := rspErr.(client.RspError)
switch {
case !ok:
glog.Errorf("unknown_error (%s, %s) => %v", logURL, endpoint, rspErr)
errCounter.Inc(logURL, endpoint, "unknown_error")
case err.Err != nil && err.StatusCode == http.StatusOK:
glog.Errorf("invalid_sct (%s, %s) => HTTP details: status=%d, body:\n%s", logURL, endpoint, err.StatusCode, err.Body)
errCounter.Inc(logURL, endpoint, "invalid_sct")
case err.Err != nil: // err.StatusCode != http.StatusOK.
glog.Errorf("connection_error (%s, %s) => HTTP details: status=%d, body:\n%s", logURL, endpoint, err.StatusCode, err.Body)
errCounter.Inc(logURL, endpoint, "connection_error")
}
}
// SubmitToLog implements Submitter interface.
func (d *Distributor) SubmitToLog(ctx context.Context, logURL string, chain []ct.ASN1Cert, asPreChain bool) (*ct.SignedCertificateTimestamp, error) {
lc, ok := d.logClients[logURL]
if !ok {
return nil, fmt.Errorf("no client registered for Log with URL %q", logURL)
}
// endpoint used for metrics
endpoint := string(ctfe.AddChainName)
if asPreChain {
endpoint = string(ctfe.AddPreChainName)
}
defer func(start time.Time) {
logRspLatency.Observe(time.Since(start).Seconds(), logURL, endpoint)
}(time.Now())
reqsCounter.Inc(logURL, endpoint)
addChain := lc.AddChain
if asPreChain {
addChain = lc.AddPreChain
}
sct, err := addChain(ctx, chain)
incRspsCounter(logURL, endpoint, err)
incErrCounter(logURL, endpoint, err)
return sct, err
}
// parseRawChain reads cert chain from bytes into x509.Certificate format.
func parseRawChain(rawChain [][]byte) ([]*x509.Certificate, error) {
parsedChain := make([]*x509.Certificate, 0, len(rawChain))
for _, certBytes := range rawChain {
cert, err := x509.ParseCertificate(certBytes)
if x509.IsFatal(err) {
return nil, fmt.Errorf("distributor unable to parse cert-chain %v", err)
}
parsedChain = append(parsedChain, cert)
}
return parsedChain, nil
}
// addSomeChain is helper calling one of AddChain or AddPreChain based
// on asPreChain param.
func (d *Distributor) addSomeChain(ctx context.Context, rawChain [][]byte, loadPendingLogs bool, asPreChain bool) ([]*AssignedSCT, error) {
if len(rawChain) == 0 {
return nil, fmt.Errorf("distributor unable to process empty chain")
}
// Helper function establishing responsibility of locking while determining log list and root chain.
compatibleLogsAndChain := func() (loglist2.LogList, []*x509.Certificate, error) {
d.mu.RLock()
defer d.mu.RUnlock()
vOpts := ctfe.NewCertValidationOpts(d.rootPool, time.Time{}, false, false, nil, nil, false, nil)
rootedChain, err := ctfe.ValidateChain(rawChain, vOpts)
if err == nil {
return d.usableLl.Compatible(rootedChain[0], rootedChain[len(rootedChain)-1], d.logRoots), rootedChain, nil
}
if d.rootDataFull {
// Could not verify the chain while root info for logs is complete.
return loglist2.LogList{}, nil, fmt.Errorf("distributor unable to process cert-chain: %v", err)
}
// Chain might be rooted to the Log which has no root-info yet.
parsedChain, err := parseRawChain(rawChain)
if err != nil {
return loglist2.LogList{}, nil, fmt.Errorf("distributor unable to parse cert-chain: %v", err)
}
return d.usableLl.Compatible(parsedChain[0], nil, d.logRoots), parsedChain, nil
}
compatibleLogs, parsedChain, err := compatibleLogsAndChain()
if err != nil {
return nil, err
}
// Distinguish between precerts and certificates.
isPrecert, err := ctfe.IsPrecertificate(parsedChain[0])
if err != nil {
return nil, fmt.Errorf("distributor unable to check certificate %v: \n%v", parsedChain[0], err)
}
if isPrecert != asPreChain {
var methodType, inputType string
if asPreChain {
methodType = "pre-"
}
if isPrecert {
inputType = "pre-"
}
return nil, fmt.Errorf("add-%schain method expected %scertificate, got %scertificate", methodType, methodType, inputType)
}
// Set up policy structs.
groups, err := d.policy.LogsByGroup(parsedChain[0], &compatibleLogs)
if err != nil {
return nil, fmt.Errorf("distributor does not have enough compatible Logs to comply with the policy: %v", err)
}
chain := make([]ct.ASN1Cert, len(parsedChain))
for i, c := range parsedChain {
chain[i] = ct.ASN1Cert{Data: c.Raw}
}
if loadPendingLogs {
go func() {
pendingGroup, err := d.pendingLogsPolicy.LogsByGroup(parsedChain[0], d.pendingQualifiedLl)
if err != nil {
return
}
GetSCTs(ctx, d, chain, asPreChain, pendingGroup)
}()
}
return GetSCTs(ctx, d, chain, asPreChain, groups)
}
// AddPreChain runs add-pre-chain calls across subset of logs according to
// Distributor's policy. May emit both SCTs array and error when SCTs
// collected do not satisfy the policy.
func (d *Distributor) AddPreChain(ctx context.Context, rawChain [][]byte, loadPendingLogs bool) ([]*AssignedSCT, error) {
return d.addSomeChain(ctx, rawChain, loadPendingLogs, true)
}
// AddChain runs add-chain calls across subset of logs according to
// Distributor's policy. May emit both SCTs array and error when SCTs
// collected do not satisfy the policy.
func (d *Distributor) AddChain(ctx context.Context, rawChain [][]byte, loadPendingLogs bool) ([]*AssignedSCT, error) {
return d.addSomeChain(ctx, rawChain, loadPendingLogs, false)
}
// LogClientBuilder builds client-interface instance for a given Log.
type LogClientBuilder func(*loglist2.Log) (client.AddLogClient, error)
// BuildLogClient is default (non-mock) LogClientBuilder.
func BuildLogClient(log *loglist2.Log) (client.AddLogClient, error) {
u, err := url.Parse(log.URL)
if err != nil {
return nil, err
}
if u.Scheme == "" {
u.Scheme = "https"
}
hc := &http.Client{Timeout: time.Second * 10}
return client.New(u.String(), hc, jsonclient.Options{PublicKeyDER: log.Key})
}
// NewDistributor creates and inits a Distributor instance.
// The Distributor will asynchronously fetch the latest roots from all of the
// logs when active. Call Run() to fetch roots and init regular updates to keep
// the local copy of the roots up-to-date.
func NewDistributor(ll *loglist2.LogList, plc ctpolicy.CTPolicy, lcBuilder LogClientBuilder, mf monitoring.MetricFactory) (*Distributor, error) {
var d Distributor
// Divide Logs by statuses.
d.ll = ll
usableStat := []loglist2.LogStatus{loglist2.UsableLogStatus}
active := ll.SelectByStatus(usableStat)
d.usableLl = &active
pendingQualifiedStat := []loglist2.LogStatus{
loglist2.PendingLogStatus, loglist2.QualifiedLogStatus}
pending := ll.SelectByStatus(pendingQualifiedStat)
d.pendingQualifiedLl = &pending
d.policy = plc
d.pendingLogsPolicy = pendingLogsPolicy{}
d.logClients = make(map[string]client.AddLogClient)
d.logRoots = make(loglist2.LogRoots)
d.rootPool = ctfe.NewPEMCertPool()
// Build clients for each of the Logs. Also build log-to-id map.
if err := d.buildLogClients(lcBuilder, d.usableLl); err != nil {
return nil, err
}
d.buildLogClients(lcBuilder, d.pendingQualifiedLl)
if mf == nil {
mf = monitoring.InertMetricFactory{}
}
distOnce.Do(func() { distInitMetrics(mf) })
return &d, nil
}
// buildLogClients builds clients for every Log provided and adds them into
// Distributor internals.
func (d *Distributor) buildLogClients(lcBuilder LogClientBuilder, ll *loglist2.LogList) error {
for _, op := range ll.Operators {
for _, log := range op.Logs {
lc, err := lcBuilder(log)
if err != nil {
return fmt.Errorf("failed to create log client for %s: %v", log.URL, err)
}
d.logClients[log.URL] = lc
}
}
return nil
}