Overhaul log processing and auditing
1. Instead of storing a single STH per log, we now store one verified STH and any number of unverified STHs. When we process a log, we verify each unverified STH using a consistency proof with the verified STH, and only delete it if it successfully verifies. We set the verified STH to the largest STH which we've successfully verified. This has two important benefits. First, we never ever delete an STH unless we can successfully verify it (previously, we would forget about an STH under certain error conditions). Second, it lays the groundwork for STH pollination. Upon reception of an STH, we can simply drop it in the log's unverified_sths directory (assuming the signature is valid), and Cert Spotter will audit it. There is no more "evidence" directory; if a consistency proof fails, the STHs will already be present elsewhere in the state directory. 2. We now persist a MerkleTreeBuilder between each run of Cert Spotter, instead of rebuilding it every time from the consistency proof. This is not intrinsically better, but it makes the code simpler considering we can now fetch numerous consistency proofs per run. 3. To accommodate the above changes, the state directory has a brand new layout. The state directory is now versioned, and Cert Spotter will automatically migrate old state directories to the new layout. This migration logic will be removed in a future Cert Spotter release. As a bonus, the code is generally cleaner now :-)
This commit is contained in:
Andrew Ayer
parent
54d9762ff2
commit
0af0262498
360
cmd/common.go
360
cmd/common.go
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@ -1,4 +1,4 @@
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// Copyright (C) 2016 Opsmate, Inc.
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// Copyright (C) 2016-2017 Opsmate, Inc.
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//
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// This Source Code Form is subject to the terms of the Mozilla
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// Public License, v. 2.0. If a copy of the MPL was not distributed
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@ -11,18 +11,13 @@ package cmd
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import (
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"bytes"
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"encoding/json"
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"flag"
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"fmt"
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"log"
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"io/ioutil"
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"os"
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"os/user"
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"path/filepath"
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"strconv"
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"strings"
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"sync"
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"time"
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"software.sslmate.com/src/certspotter"
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"software.sslmate.com/src/certspotter/ct"
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@ -36,7 +31,7 @@ var underwater = flag.Bool("underwater", false, "Monitor certificates from distr
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var noSave = flag.Bool("no_save", false, "Do not save a copy of matching certificates")
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var verbose = flag.Bool("verbose", false, "Be verbose")
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var allTime = flag.Bool("all_time", false, "Scan certs from all time, not just since last scan")
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var stateDir string
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var state *State
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var printMutex sync.Mutex
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@ -64,7 +59,7 @@ func LogEntry(info *certspotter.EntryInfo) {
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if !*noSave {
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var alreadyPresent bool
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var err error
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alreadyPresent, info.Filename, err = certspotter.WriteCertRepository(filepath.Join(stateDir, "certs"), info.IsPrecert, info.FullChain)
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alreadyPresent, info.Filename, err = state.SaveCert(info.IsPrecert, info.FullChain)
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if err != nil {
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log.Print(err)
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}
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@ -85,191 +80,240 @@ func LogEntry(info *certspotter.EntryInfo) {
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}
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}
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func defangLogUri(logUri string) string {
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return strings.Replace(strings.Replace(logUri, "://", "_", 1), "/", "_", -1)
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}
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func saveEvidence(logUri string, firstSTH *ct.SignedTreeHead, secondSTH *ct.SignedTreeHead, proof ct.ConsistencyProof) (string, string, string, error) {
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now := strconv.FormatInt(time.Now().Unix(), 10)
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firstFilename := filepath.Join(stateDir, "evidence", defangLogUri(logUri)+".inconsistent."+now+".first")
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if err := certspotter.WriteSTHFile(firstFilename, firstSTH); err != nil {
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return "", "", "", err
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}
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secondFilename := filepath.Join(stateDir, "evidence", defangLogUri(logUri)+".inconsistent."+now+".second")
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if err := certspotter.WriteSTHFile(secondFilename, secondSTH); err != nil {
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return "", "", "", err
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}
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proofFilename := filepath.Join(stateDir, "evidence", defangLogUri(logUri)+".inconsistent."+now+".proof")
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if err := certspotter.WriteProofFile(proofFilename, proof); err != nil {
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return "", "", "", err
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}
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return firstFilename, secondFilename, proofFilename, nil
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}
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func fileExists (path string) bool {
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_, err := os.Lstat(path)
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return err == nil
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}
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func Main(argStateDir string, processCallback certspotter.ProcessCallback) int {
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stateDir = argStateDir
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var logs []certspotter.LogInfo
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func loadLogList () ([]certspotter.LogInfo, error) {
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if *logsFilename != "" {
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logsJson, err := ioutil.ReadFile(*logsFilename)
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if err != nil {
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fmt.Fprintf(os.Stderr, "%s: Error reading logs file: %s: %s\n", os.Args[0], *logsFilename, err)
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return 1
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}
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var logFileObj certspotter.LogInfoFile
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if err := json.Unmarshal(logsJson, &logFileObj); err != nil {
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fmt.Fprintf(os.Stderr, "%s: Error decoding logs file: %s: %s\n", os.Args[0], *logsFilename, err)
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return 1
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if err := readJSONFile(*logsFilename, &logFileObj); err != nil {
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return nil, fmt.Errorf("Error reading logs file: %s: %s", *logsFilename, err)
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}
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logs = logFileObj.Logs
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return logFileObj.Logs, nil
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} else if *underwater {
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logs = certspotter.UnderwaterLogs
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return certspotter.UnderwaterLogs, nil
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} else {
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logs = certspotter.DefaultLogs
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return certspotter.DefaultLogs, nil
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}
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}
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firstRun := !fileExists(filepath.Join(stateDir, "once"))
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type logHandle struct {
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scanner *certspotter.Scanner
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state *LogState
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position *certspotter.MerkleTreeBuilder
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verifiedSTH *ct.SignedTreeHead
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}
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if err := os.Mkdir(stateDir, 0777); err != nil && !os.IsExist(err) {
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fmt.Fprintf(os.Stderr, "%s: Error creating state directory: %s: %s\n", os.Args[0], stateDir, err)
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return 1
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}
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for _, subdir := range []string{"certs", "sths", "evidence"} {
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path := filepath.Join(stateDir, subdir)
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if err := os.Mkdir(path, 0777); err != nil && !os.IsExist(err) {
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fmt.Fprintf(os.Stderr, "%s: Error creating state directory: %s: %s\n", os.Args[0], path, err)
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return 1
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}
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}
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func makeLogHandle(logInfo *certspotter.LogInfo) (*logHandle, error) {
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ctlog := new(logHandle)
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/*
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* Exit code bits:
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* 1 = initialization/configuration/system error
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* 2 = usage error
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* 4 = error communicating with log
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* 8 = log misbehavior
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*/
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exitCode := 0
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for _, logInfo := range logs {
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logUri := logInfo.FullURI()
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log.SetPrefix(os.Args[0] + ": " + logUri + ": ")
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logKey, err := logInfo.ParsedPublicKey()
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if err != nil {
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log.Printf("Bad public key: %s\n", err)
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exitCode |= 1
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continue
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return nil, fmt.Errorf("Bad public key: %s", err)
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}
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stateFilename := filepath.Join(stateDir, "sths", defangLogUri(logUri))
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prevSTH, err := certspotter.ReadSTHFile(stateFilename)
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if err != nil {
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log.Printf("Error reading state file: %s: %s\n", stateFilename, err)
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exitCode |= 1
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continue
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}
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opts := certspotter.ScannerOptions{
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ctlog.scanner = certspotter.NewScanner(logInfo.FullURI(), logKey, &certspotter.ScannerOptions{
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BatchSize: *batchSize,
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NumWorkers: *numWorkers,
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Quiet: !*verbose,
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}
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scanner := certspotter.NewScanner(logUri, logKey, &opts)
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})
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latestSTH, err := scanner.GetSTH()
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ctlog.state, err = state.OpenLogState(logInfo)
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if err != nil {
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log.Printf("Error retrieving STH from log: %s\n", err)
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exitCode |= 4
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continue
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return nil, fmt.Errorf("Error opening state directory: %s", err)
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}
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if *verbose {
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if *allTime {
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log.Printf("Scanning all %d entries in the log because -all_time option specified", latestSTH.TreeSize)
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} else if prevSTH != nil {
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log.Printf("Existing log; scanning %d new entries since previous scan (previous size %d, previous root hash = %x)", latestSTH.TreeSize-prevSTH.TreeSize, prevSTH.TreeSize, prevSTH.SHA256RootHash)
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} else if firstRun {
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log.Printf("First run of Cert Spotter; not scanning %d existing entries because -all_time option not specified", latestSTH.TreeSize)
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} else {
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log.Printf("New log; scanning all %d entries in the log", latestSTH.TreeSize)
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}
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}
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var startIndex uint64
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if *allTime {
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startIndex = 0
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} else if prevSTH != nil {
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startIndex = prevSTH.TreeSize
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} else if firstRun {
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startIndex = latestSTH.TreeSize
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} else {
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startIndex = 0
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}
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if latestSTH.TreeSize > startIndex {
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var treeBuilder *certspotter.MerkleTreeBuilder
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if prevSTH != nil {
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var valid bool
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var err error
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var proof ct.ConsistencyProof
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valid, treeBuilder, proof, err = scanner.CheckConsistency(prevSTH, latestSTH)
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ctlog.position, err = ctlog.state.GetLogPosition()
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if err != nil {
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log.Printf("Error fetching consistency proof: %s\n", err)
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exitCode |= 4
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continue
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return nil, fmt.Errorf("Error loading log position: %s", err)
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}
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if !valid {
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firstFilename, secondFilename, proofFilename, err := saveEvidence(logUri, prevSTH, latestSTH, proof)
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ctlog.verifiedSTH, err = ctlog.state.GetVerifiedSTH()
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if err != nil {
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log.Printf("Consistency proof failed - the log has misbehaved! Saving evidence of misbehavior failed: %s\n", err)
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} else {
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log.Printf("Consistency proof failed - the log has misbehaved! Evidence of misbehavior has been saved to '%s' and '%s' (with proof in '%s').\n", firstFilename, secondFilename, proofFilename)
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}
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exitCode |= 8
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continue
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}
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} else {
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treeBuilder = &certspotter.MerkleTreeBuilder{}
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return nil, fmt.Errorf("Error loading verified STH: %s", err)
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}
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if err := scanner.Scan(int64(startIndex), int64(latestSTH.TreeSize), processCallback, treeBuilder); err != nil {
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log.Printf("Error scanning log: %s\n", err)
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exitCode |= 4
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continue
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if ctlog.position == nil && ctlog.verifiedSTH == nil { // This branch can be removed eventually
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legacySTH, err := state.GetLegacySTH(logInfo);
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if err != nil {
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return nil, fmt.Errorf("Error loading legacy STH: %s", err)
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}
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if legacySTH != nil {
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ctlog.position, err = ctlog.scanner.MakeMerkleTreeBuilder(legacySTH)
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if err != nil {
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return nil, fmt.Errorf("Error reconstructing Merkle Tree for legacy STH: %s", err)
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}
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if err := ctlog.state.StoreLogPosition(ctlog.position); err != nil {
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return nil, fmt.Errorf("Error storing log position: %s", err)
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}
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if err := ctlog.state.StoreVerifiedSTH(legacySTH); err != nil {
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return nil, fmt.Errorf("Error storing verified STH: %s", err)
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}
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state.RemoveLegacySTH(logInfo)
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}
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}
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return ctlog, nil
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}
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func (ctlog *logHandle) refresh () error {
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latestSTH, err := ctlog.scanner.GetSTH()
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if err != nil {
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return fmt.Errorf("Error retrieving STH from log: %s", err)
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}
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if ctlog.verifiedSTH == nil {
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ctlog.verifiedSTH = latestSTH
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if err := ctlog.state.StoreVerifiedSTH(ctlog.verifiedSTH); err != nil {
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return fmt.Errorf("Error storing verified STH: %s", err)
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}
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} else {
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if err := ctlog.state.StoreUnverifiedSTH(latestSTH); err != nil {
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return fmt.Errorf("Error storing unverified STH: %s", err)
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}
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}
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return nil
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}
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func (ctlog *logHandle) audit () error {
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sths, err := ctlog.state.GetUnverifiedSTHs()
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if err != nil {
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return fmt.Errorf("Error loading unverified STHs: %s", err)
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}
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for _, sth := range sths {
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if sth.TreeSize > ctlog.verifiedSTH.TreeSize {
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isValid, _, _, err := ctlog.scanner.CheckConsistency(ctlog.verifiedSTH, sth)
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if err != nil {
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return fmt.Errorf("Error fetching consistency proof between %d and %d (if this error persists, it should be construed as misbehavior by the log): %s", ctlog.verifiedSTH.TreeSize, sth.TreeSize, err)
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}
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if !isValid {
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return fmt.Errorf("Log has misbehaved: STH in '%s' is not consistent with STH in '%s'", ctlog.state.VerifiedSTHFilename(), ctlog.state.UnverifiedSTHFilename(sth))
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}
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ctlog.verifiedSTH = sth
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if err := ctlog.state.StoreVerifiedSTH(ctlog.verifiedSTH); err != nil {
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return fmt.Errorf("Error storing verified STH: %s", err)
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}
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} else if sth.TreeSize < ctlog.verifiedSTH.TreeSize {
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isValid, _, _, err := ctlog.scanner.CheckConsistency(sth, ctlog.verifiedSTH)
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if err != nil {
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return fmt.Errorf("Error fetching consistency proof between %d and %d (if this error persists, it should be construed as misbehavior by the log): %s", ctlog.verifiedSTH.TreeSize, sth.TreeSize, err)
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}
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if !isValid {
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return fmt.Errorf("Log has misbehaved: STH in '%s' is not consistent with STH in '%s'", ctlog.state.VerifiedSTHFilename(), ctlog.state.UnverifiedSTHFilename(sth))
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}
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} else {
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if !bytes.Equal(sth.SHA256RootHash[:], ctlog.verifiedSTH.SHA256RootHash[:]) {
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return fmt.Errorf("Log has misbehaved: STH in '%s' is not consistent with STH in '%s'", ctlog.state.VerifiedSTHFilename(), ctlog.state.UnverifiedSTHFilename(sth))
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}
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}
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if err := ctlog.state.RemoveUnverifiedSTH(sth); err != nil {
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return fmt.Errorf("Error removing redundant STH: %s", err)
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}
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}
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return nil
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}
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func (ctlog *logHandle) scan (processCallback certspotter.ProcessCallback) error {
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startIndex := int64(ctlog.position.GetNumLeaves())
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endIndex := int64(ctlog.verifiedSTH.TreeSize)
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if endIndex > startIndex {
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treeBuilder := ctlog.position
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ctlog.position = nil
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if err := ctlog.scanner.Scan(startIndex, endIndex, processCallback, treeBuilder); err != nil {
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return fmt.Errorf("Error scanning log (if this error persists, it should be construed as misbehavior by the log): %s", err)
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}
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rootHash := treeBuilder.CalculateRoot()
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if !bytes.Equal(rootHash, latestSTH.SHA256RootHash[:]) {
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log.Printf("Validation of log entries failed - calculated tree root (%x) does not match signed tree root (%s). If this error persists for an extended period, it should be construed as misbehavior by the log.\n", rootHash, latestSTH.SHA256RootHash)
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exitCode |= 8
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continue
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if !bytes.Equal(rootHash, ctlog.verifiedSTH.SHA256RootHash[:]) {
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return fmt.Errorf("Log has misbehaved: log entries at tree size %d do not correspond to signed tree root", ctlog.verifiedSTH.TreeSize)
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}
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ctlog.position = treeBuilder
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}
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if err := ctlog.state.StoreLogPosition(ctlog.position); err != nil {
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return fmt.Errorf("Error storing log position: %s", err)
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}
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return nil
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}
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func processLog(logInfo* certspotter.LogInfo, processCallback certspotter.ProcessCallback) int {
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log.SetPrefix(os.Args[0] + ": " + logInfo.Url + ": ")
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ctlog, err := makeLogHandle(logInfo)
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if err != nil {
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log.Printf("%s\n", err)
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return 1
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}
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if err := ctlog.refresh(); err != nil {
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log.Printf("%s\n", err)
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return 1
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}
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if err := ctlog.audit(); err != nil {
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log.Printf("%s\n", err)
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return 1
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}
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if *allTime {
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ctlog.position = certspotter.EmptyMerkleTreeBuilder()
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if *verbose {
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log.Printf("Scanning all %d entries in the log because -all_time option specified", ctlog.verifiedSTH.TreeSize)
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}
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} else if ctlog.position != nil {
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if *verbose {
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log.Printf("Existing log; scanning %d new entries since previous scan", ctlog.verifiedSTH.TreeSize-ctlog.position.GetNumLeaves())
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}
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} else if state.IsFirstRun() {
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ctlog.position, err = ctlog.scanner.MakeMerkleTreeBuilder(ctlog.verifiedSTH)
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if err != nil {
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log.Printf("Error reconstructing Merkle Tree: %s", err)
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return 1
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}
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if *verbose {
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log.Printf("First run of Cert Spotter; not scanning %d existing entries because -all_time option not specified", ctlog.verifiedSTH.TreeSize)
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}
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} else {
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ctlog.position = certspotter.EmptyMerkleTreeBuilder()
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if *verbose {
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log.Printf("New log; scanning all %d entries in the log", ctlog.verifiedSTH.TreeSize)
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}
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}
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if err := ctlog.scan(processCallback); err != nil {
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log.Printf("%s\n", err)
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return 1
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}
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if *verbose {
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log.Printf("final log size = %d, final root hash = %x", latestSTH.TreeSize, latestSTH.SHA256RootHash)
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log.Printf("Final log size = %d, final root hash = %x", ctlog.verifiedSTH.TreeSize, ctlog.verifiedSTH.SHA256RootHash)
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}
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if err := certspotter.WriteSTHFile(stateFilename, latestSTH); err != nil {
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log.Printf("Error writing state file: %s: %s\n", stateFilename, err)
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exitCode |= 1
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continue
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}
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return 0
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}
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func Main(statePath string, processCallback certspotter.ProcessCallback) int {
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var err error
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state, err = OpenState(statePath)
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if err != nil {
|
||||
fmt.Fprintf(os.Stderr, "%s: %s\n", os.Args[0], err)
|
||||
return 1
|
||||
}
|
||||
|
||||
if firstRun {
|
||||
if err := ioutil.WriteFile(filepath.Join(stateDir, "once"), []byte{}, 0666); err != nil {
|
||||
log.Printf("Error writing once file: %s\n", err)
|
||||
exitCode |= 1
|
||||
logs, err := loadLogList()
|
||||
if err != nil {
|
||||
fmt.Fprintf(os.Stderr, "%s: %s\n", os.Args[0], err)
|
||||
return 1
|
||||
}
|
||||
|
||||
exitCode := 0
|
||||
for i := range logs {
|
||||
exitCode |= processLog(&logs[i], processCallback)
|
||||
}
|
||||
|
||||
if err := state.Finish(); err != nil {
|
||||
fmt.Fprintf(os.Stderr, "%s: Error finalizing state: %s\n", os.Args[0], err)
|
||||
exitCode |= 1
|
||||
}
|
||||
|
||||
return exitCode
|
||||
|
|
|
|||
|
|
@ -0,0 +1,87 @@
|
|||
// Copyright (C) 2017 Opsmate, Inc.
|
||||
//
|
||||
// This Source Code Form is subject to the terms of the Mozilla
|
||||
// Public License, v. 2.0. If a copy of the MPL was not distributed
|
||||
// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
|
||||
//
|
||||
// This software is distributed WITHOUT A WARRANTY OF ANY KIND.
|
||||
// See the Mozilla Public License for details.
|
||||
|
||||
package cmd
|
||||
|
||||
import (
|
||||
"crypto/sha256"
|
||||
"encoding/hex"
|
||||
"encoding/json"
|
||||
"io/ioutil"
|
||||
"os"
|
||||
|
||||
"software.sslmate.com/src/certspotter/ct"
|
||||
)
|
||||
|
||||
func fileExists(path string) bool {
|
||||
_, err := os.Lstat(path)
|
||||
return err == nil
|
||||
}
|
||||
|
||||
func writeFile(filename string, data []byte, perm os.FileMode) error {
|
||||
tempname := filename + ".new"
|
||||
if err := ioutil.WriteFile(tempname, data, perm); err != nil {
|
||||
return err
|
||||
}
|
||||
if err := os.Rename(tempname, filename); err != nil {
|
||||
os.Remove(tempname)
|
||||
return err
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
func writeJSONFile(filename string, obj interface{}, perm os.FileMode) error {
|
||||
tempname := filename + ".new"
|
||||
f, err := os.OpenFile(tempname, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, perm)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
if err := json.NewEncoder(f).Encode(obj); err != nil {
|
||||
f.Close()
|
||||
os.Remove(tempname)
|
||||
return err
|
||||
}
|
||||
if err := f.Close(); err != nil {
|
||||
os.Remove(tempname)
|
||||
return err
|
||||
}
|
||||
if err := os.Rename(tempname, filename); err != nil {
|
||||
os.Remove(tempname)
|
||||
return err
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
func readJSONFile(filename string, obj interface{}) error {
|
||||
bytes, err := ioutil.ReadFile(filename)
|
||||
if err != nil {
|
||||
return err
|
||||
}
|
||||
if err = json.Unmarshal(bytes, obj); err != nil {
|
||||
return err
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
func readSTHFile(filename string) (*ct.SignedTreeHead, error) {
|
||||
sth := new(ct.SignedTreeHead)
|
||||
if err := readJSONFile(filename, sth); err != nil {
|
||||
return nil, err
|
||||
}
|
||||
return sth, nil
|
||||
}
|
||||
|
||||
func sha256sum(data []byte) []byte {
|
||||
sum := sha256.Sum256(data)
|
||||
return sum[:]
|
||||
}
|
||||
|
||||
func sha256hex(data []byte) string {
|
||||
return hex.EncodeToString(sha256sum(data))
|
||||
}
|
||||
|
|
@ -0,0 +1,146 @@
|
|||
// Copyright (C) 2017 Opsmate, Inc.
|
||||
//
|
||||
// This Source Code Form is subject to the terms of the Mozilla
|
||||
// Public License, v. 2.0. If a copy of the MPL was not distributed
|
||||
// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
|
||||
//
|
||||
// This software is distributed WITHOUT A WARRANTY OF ANY KIND.
|
||||
// See the Mozilla Public License for details.
|
||||
|
||||
package cmd
|
||||
|
||||
import (
|
||||
"crypto/sha256"
|
||||
"encoding/base64"
|
||||
"encoding/binary"
|
||||
"fmt"
|
||||
"os"
|
||||
"path/filepath"
|
||||
"strings"
|
||||
|
||||
"software.sslmate.com/src/certspotter"
|
||||
"software.sslmate.com/src/certspotter/ct"
|
||||
)
|
||||
|
||||
type LogState struct {
|
||||
path string
|
||||
}
|
||||
|
||||
// generate a filename that uniquely identifies the STH (within the context of a particular log)
|
||||
func sthFilename (sth *ct.SignedTreeHead) string {
|
||||
hasher := sha256.New()
|
||||
switch sth.Version {
|
||||
case ct.V1:
|
||||
binary.Write(hasher, binary.LittleEndian, sth.Version)
|
||||
binary.Write(hasher, binary.LittleEndian, sth.TreeSize)
|
||||
binary.Write(hasher, binary.LittleEndian, sth.Timestamp)
|
||||
binary.Write(hasher, binary.LittleEndian, sth.SHA256RootHash)
|
||||
default:
|
||||
panic(fmt.Sprintf("Unsupported STH version %d", sth.Version))
|
||||
}
|
||||
// For 6962-bis, we will need to handle a variable-length root hash, and include the signature in the filename hash (since signatures must be deterministic)
|
||||
return base64.RawURLEncoding.EncodeToString(hasher.Sum(nil))
|
||||
}
|
||||
|
||||
func makeLogStateDir (logStatePath string) error {
|
||||
if err := os.Mkdir(logStatePath, 0777); err != nil && !os.IsExist(err) {
|
||||
return fmt.Errorf("%s: %s", logStatePath, err)
|
||||
}
|
||||
for _, subdir := range []string{"unverified_sths"} {
|
||||
path := filepath.Join(logStatePath, subdir)
|
||||
if err := os.Mkdir(path, 0777); err != nil && !os.IsExist(err) {
|
||||
return fmt.Errorf("%s: %s", path, err)
|
||||
}
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
func OpenLogState (logStatePath string) (*LogState, error) {
|
||||
if err := makeLogStateDir(logStatePath); err != nil {
|
||||
return nil, fmt.Errorf("Error creating log state directory: %s", err)
|
||||
}
|
||||
return &LogState{path: logStatePath}, nil
|
||||
}
|
||||
|
||||
func (logState *LogState) VerifiedSTHFilename () string {
|
||||
return filepath.Join(logState.path, "verified_sth")
|
||||
}
|
||||
|
||||
func (logState *LogState) GetVerifiedSTH () (*ct.SignedTreeHead, error) {
|
||||
sth, err := readSTHFile(logState.VerifiedSTHFilename())
|
||||
if err != nil {
|
||||
if os.IsNotExist(err) {
|
||||
return nil, nil
|
||||
} else {
|
||||
return nil, err
|
||||
}
|
||||
}
|
||||
return sth, nil
|
||||
}
|
||||
|
||||
func (logState *LogState) StoreVerifiedSTH (sth *ct.SignedTreeHead) error {
|
||||
return writeJSONFile(logState.VerifiedSTHFilename(), sth, 0666)
|
||||
}
|
||||
|
||||
func (logState *LogState) GetUnverifiedSTHs () ([]*ct.SignedTreeHead, error) {
|
||||
dir, err := os.Open(filepath.Join(logState.path, "unverified_sths"))
|
||||
if err != nil {
|
||||
if os.IsNotExist(err) {
|
||||
return []*ct.SignedTreeHead{}, nil
|
||||
} else {
|
||||
return nil, err
|
||||
}
|
||||
}
|
||||
filenames, err := dir.Readdirnames(0)
|
||||
if err != nil {
|
||||
return nil, err
|
||||
}
|
||||
|
||||
sths := make([]*ct.SignedTreeHead, 0, len(filenames))
|
||||
for _, filename := range filenames {
|
||||
if !strings.HasPrefix(filename, ".") {
|
||||
sth, _ := readSTHFile(filepath.Join(dir.Name(), filename))
|
||||
if sth != nil {
|
||||
sths = append(sths, sth)
|
||||
}
|
||||
}
|
||||
}
|
||||
return sths, nil
|
||||
}
|
||||
|
||||
func (logState *LogState) UnverifiedSTHFilename (sth *ct.SignedTreeHead) string {
|
||||
return filepath.Join(logState.path, "unverified_sths", sthFilename(sth))
|
||||
}
|
||||
|
||||
func (logState *LogState) StoreUnverifiedSTH (sth *ct.SignedTreeHead) error {
|
||||
filename := logState.UnverifiedSTHFilename(sth)
|
||||
if fileExists(filename) {
|
||||
return nil
|
||||
}
|
||||
return writeJSONFile(filename, sth, 0666)
|
||||
}
|
||||
|
||||
func (logState *LogState) RemoveUnverifiedSTH (sth *ct.SignedTreeHead) error {
|
||||
filename := logState.UnverifiedSTHFilename(sth)
|
||||
err := os.Remove(filepath.Join(filename))
|
||||
if err != nil && !os.IsNotExist(err) {
|
||||
return err
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
func (logState *LogState) GetLogPosition () (*certspotter.MerkleTreeBuilder, error) {
|
||||
builder := new(certspotter.MerkleTreeBuilder)
|
||||
if err := readJSONFile(filepath.Join(logState.path, "position"), builder); err != nil {
|
||||
if os.IsNotExist(err) {
|
||||
return nil, nil
|
||||
} else {
|
||||
return nil, err
|
||||
}
|
||||
}
|
||||
return builder, nil
|
||||
}
|
||||
|
||||
func (logState *LogState) StoreLogPosition (builder *certspotter.MerkleTreeBuilder) error {
|
||||
return writeJSONFile(filepath.Join(logState.path, "position"), builder, 0666)
|
||||
}
|
||||
|
|
@ -0,0 +1,181 @@
|
|||
// Copyright (C) 2017 Opsmate, Inc.
|
||||
//
|
||||
// This Source Code Form is subject to the terms of the Mozilla
|
||||
// Public License, v. 2.0. If a copy of the MPL was not distributed
|
||||
// with this file, You can obtain one at http://mozilla.org/MPL/2.0/.
|
||||
//
|
||||
// This software is distributed WITHOUT A WARRANTY OF ANY KIND.
|
||||
// See the Mozilla Public License for details.
|
||||
|
||||
package cmd
|
||||
|
||||
import (
|
||||
"bytes"
|
||||
"encoding/base64"
|
||||
"encoding/pem"
|
||||
"fmt"
|
||||
"io/ioutil"
|
||||
"os"
|
||||
"path/filepath"
|
||||
"strconv"
|
||||
"strings"
|
||||
|
||||
"software.sslmate.com/src/certspotter"
|
||||
"software.sslmate.com/src/certspotter/ct"
|
||||
)
|
||||
|
||||
type State struct {
|
||||
path string
|
||||
}
|
||||
|
||||
func legacySTHFilename(logInfo *certspotter.LogInfo) string {
|
||||
return strings.Replace(strings.Replace(logInfo.FullURI(), "://", "_", 1), "/", "_", -1)
|
||||
}
|
||||
|
||||
func readVersionFile (statePath string) (int, error) {
|
||||
versionFilePath := filepath.Join(statePath, "version")
|
||||
versionBytes, err := ioutil.ReadFile(versionFilePath)
|
||||
if err == nil {
|
||||
version, err := strconv.Atoi(string(bytes.TrimSpace(versionBytes)))
|
||||
if err != nil {
|
||||
return -1, fmt.Errorf("%s: contains invalid integer: %s", versionFilePath, err)
|
||||
}
|
||||
if version < 0 {
|
||||
return -1, fmt.Errorf("%s: contains negative integer", versionFilePath)
|
||||
}
|
||||
return version, nil
|
||||
} else if os.IsNotExist(err) {
|
||||
if fileExists(filepath.Join(statePath, "sths")) {
|
||||
// Original version of certspotter had no version file.
|
||||
// Infer version 0 if "sths" directory is present.
|
||||
return 0, nil
|
||||
}
|
||||
return -1, nil
|
||||
} else {
|
||||
return -1, fmt.Errorf("%s: %s", versionFilePath, err)
|
||||
}
|
||||
}
|
||||
|
||||
func writeVersionFile (statePath string) error {
|
||||
version := 1
|
||||
versionString := fmt.Sprintf("%d\n", version)
|
||||
versionFilePath := filepath.Join(statePath, "version")
|
||||
if err := ioutil.WriteFile(versionFilePath, []byte(versionString), 0666); err != nil {
|
||||
return fmt.Errorf("%s: %s\n", versionFilePath, err)
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
func makeStateDir (statePath string) error {
|
||||
if err := os.Mkdir(statePath, 0777); err != nil && !os.IsExist(err) {
|
||||
return fmt.Errorf("%s: %s", statePath, err)
|
||||
}
|
||||
for _, subdir := range []string{"certs", "logs"} {
|
||||
path := filepath.Join(statePath, subdir)
|
||||
if err := os.Mkdir(path, 0777); err != nil && !os.IsExist(err) {
|
||||
return fmt.Errorf("%s: %s", path, err)
|
||||
}
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
func OpenState (statePath string) (*State, error) {
|
||||
version, err := readVersionFile(statePath)
|
||||
if err != nil {
|
||||
return nil, fmt.Errorf("Error reading version file: %s", err)
|
||||
}
|
||||
|
||||
if version < 1 {
|
||||
if err := makeStateDir(statePath); err != nil {
|
||||
return nil, fmt.Errorf("Error creating state directory: %s", err)
|
||||
}
|
||||
if version == 0 {
|
||||
if err := os.Rename(filepath.Join(statePath, "sths"), filepath.Join(statePath, "legacy_sths")); err != nil {
|
||||
return nil, fmt.Errorf("Error migrating STHs directory: %s", err)
|
||||
}
|
||||
for _, subdir := range []string{"evidence", "legacy_sths"} {
|
||||
os.Remove(filepath.Join(statePath, subdir))
|
||||
}
|
||||
if err := ioutil.WriteFile(filepath.Join(statePath, "once"), []byte{}, 0666); err != nil {
|
||||
return nil, fmt.Errorf("Error creating once file: %s", err)
|
||||
}
|
||||
}
|
||||
if err := writeVersionFile(statePath); err != nil {
|
||||
return nil, fmt.Errorf("Error writing version file: %s", err)
|
||||
}
|
||||
} else if version > 1 {
|
||||
return nil, fmt.Errorf("%s was created by a newer version of Cert Spotter; please remove this directory or upgrade Cert Spotter", statePath)
|
||||
}
|
||||
|
||||
return &State{path: statePath}, nil
|
||||
}
|
||||
|
||||
func (state *State) IsFirstRun() bool {
|
||||
return !fileExists(filepath.Join(state.path, "once"))
|
||||
}
|
||||
|
||||
func (state *State) Finish() error {
|
||||
if err := ioutil.WriteFile(filepath.Join(state.path, "once"), []byte{}, 0666); err != nil {
|
||||
return fmt.Errorf("Error writing once file: %s", err)
|
||||
}
|
||||
return nil
|
||||
}
|
||||
|
||||
func (state *State) SaveCert(isPrecert bool, certs [][]byte) (bool, string, error) {
|
||||
if len(certs) == 0 {
|
||||
return false, "", fmt.Errorf("Cannot write an empty certificate chain")
|
||||
}
|
||||
|
||||
fingerprint := sha256hex(certs[0])
|
||||
prefixPath := filepath.Join(state.path, "certs", fingerprint[0:2])
|
||||
var filenameSuffix string
|
||||
if isPrecert {
|
||||
filenameSuffix = ".precert.pem"
|
||||
} else {
|
||||
filenameSuffix = ".cert.pem"
|
||||
}
|
||||
if err := os.Mkdir(prefixPath, 0777); err != nil && !os.IsExist(err) {
|
||||
return false, "", fmt.Errorf("Failed to create prefix directory %s: %s", prefixPath, err)
|
||||
}
|
||||
path := filepath.Join(prefixPath, fingerprint+filenameSuffix)
|
||||
file, err := os.OpenFile(path, os.O_WRONLY|os.O_CREATE|os.O_EXCL, 0666)
|
||||
if err != nil {
|
||||
if os.IsExist(err) {
|
||||
return true, path, nil
|
||||
} else {
|
||||
return false, path, fmt.Errorf("Failed to open %s for writing: %s", path, err)
|
||||
}
|
||||
}
|
||||
for _, cert := range certs {
|
||||
if err := pem.Encode(file, &pem.Block{Type: "CERTIFICATE", Bytes: cert}); err != nil {
|
||||
file.Close()
|
||||
return false, path, fmt.Errorf("Error writing to %s: %s", path, err)
|
||||
}
|
||||
}
|
||||
if err := file.Close(); err != nil {
|
||||
return false, path, fmt.Errorf("Error writing to %s: %s", path, err)
|
||||
}
|
||||
|
||||
return false, path, nil
|
||||
}
|
||||
|
||||
func (state *State) OpenLogState(logInfo *certspotter.LogInfo) (*LogState, error) {
|
||||
return OpenLogState(filepath.Join(state.path, "logs", base64.RawURLEncoding.EncodeToString(logInfo.ID())))
|
||||
}
|
||||
|
||||
func (state *State) GetLegacySTH(logInfo *certspotter.LogInfo) (*ct.SignedTreeHead, error) {
|
||||
sth, err := readSTHFile(filepath.Join(state.path, "legacy_sths", legacySTHFilename(logInfo)))
|
||||
if err != nil {
|
||||
if os.IsNotExist(err) {
|
||||
return nil, nil
|
||||
} else {
|
||||
return nil, err
|
||||
}
|
||||
}
|
||||
return sth, nil
|
||||
}
|
||||
func (state *State) RemoveLegacySTH(logInfo *certspotter.LogInfo) error {
|
||||
err := os.Remove(filepath.Join(state.path, "legacy_sths", legacySTHFilename(logInfo)))
|
||||
os.Remove(filepath.Join(state.path, "legacy_sths"))
|
||||
return err
|
||||
}
|
||||
Loading…
Reference in New Issue