First stab at tesseract config generator. Generate HTML files in each of the log dirs

This commit is contained in:
Pim van Pelt
2025-08-24 10:46:47 +02:00
parent a12eccfc1d
commit ebfa490a49
3 changed files with 268 additions and 0 deletions

259
tesseract/genconf/main.go Normal file
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package main
import (
"crypto/sha256"
"crypto/x509"
"encoding/base64"
"encoding/pem"
"flag"
"fmt"
"log"
"os"
"text/template"
"time"
"gopkg.in/yaml.v3"
)
type Config struct {
Listen []string `yaml:"listen"`
Checkpoints string `yaml:"checkpoints"`
Logs []Log `yaml:"logs"`
}
type Log struct {
ShortName string `yaml:"shortname"`
Inception string `yaml:"inception"`
Period int `yaml:"period"`
PoolSize int `yaml:"poolsize"`
SubmissionPrefix string `yaml:"submissionprefix"`
MonitoringPrefix string `yaml:"monitoringprefix"`
CCadbRoots string `yaml:"ccadbroots"`
ExtraRoots string `yaml:"extraroots"`
Secret string `yaml:"secret"`
Cache string `yaml:"cache"`
LocalDirectory string `yaml:"localdirectory"`
NotAfterStart time.Time `yaml:"notafterstart"`
NotAfterLimit time.Time `yaml:"notafterlimit"`
// Computed fields
LogID string
PublicKeyPEM string
PublicKeyDERB64 string
}
const htmlTemplate = `<!DOCTYPE html>
<html lang="en">
<head>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1.0">
<title>TesseraCT</title>
<link rel="preconnect" href="https://fonts.googleapis.com">
<link rel="preconnect" href="https://fonts.gstatic.com" crossorigin>
<link href="https://fonts.googleapis.com/css2?family=Bitter&family=Raleway&family=Source+Code+Pro&display=swap" rel="stylesheet">
<style>
.container {
width: auto;
max-width: 700px;
padding: 0 15px;
margin: 80px auto;
}
body {
font-family: "Raleway", sans-serif;
line-height: 1.4;
}
h1, h2, h3 {
font-family: "Bitter", serif;
}
code {
font-family: "Source Code Pro", monospace;
-webkit-font-smoothing: antialiased;
}
.response {
white-space: wrap;
word-break: break-all;
}
</style>
</head>
<body>
<div class="container">
<p align="center">
<img alt="A TesseraCT logo, a stylized four-dimensional hypercube with on the left side penstrokes of orange with a padlock, and on the right penstrokes of dark blue with a magnifying glass." width="250" height="278" src="https://ipng.ch/assets/ctlog/tesseract-logo.png"> </p>
<p>
This is a <a href="https://github.com/transparency-dev/tesseract">TesseraCT</a> Certificate Transparency log instance.
<hr>
<p>
The following logs are active.
{{range .Logs}}
<h2>{{.ShortName}}.log.ct.ipng.ch</h2>
<p>
Log ID: <code>{{.LogID}}</code><br>
Monitoring prefix: <code>{{.MonitoringPrefix}}/</code><br>
Submission prefix: <code>{{.SubmissionPrefix}}/</code><br>
Interval: {{.NotAfterStart.Format "2006-01-02T15:04:05Z"}} {{.NotAfterLimit.Format "2006-01-02T15:04:05Z"}}<br>
Links: <a href="{{.MonitoringPrefix}}/checkpoint">checkpoint</a>
<a href="data:application/octet-stream;base64,{{.PublicKeyDERB64}}"
download="{{.ShortName}}.der">key</a>
<a href="{{.SubmissionPrefix}}/ct/v1/get-roots">get-roots</a>
<a href="{{.SubmissionPrefix}}/log.v3.json">json</a><br>
Ratelimit: {{.PoolSize}} req/s
<pre><code>{{.PublicKeyPEM}}</code></pre>
{{end}}
</body>
</html>
`
func main() {
configFile := flag.String("c", "./tesseract-staging.yaml", "Path to the YAML configuration file")
flag.Parse()
args := flag.Args()
if len(args) == 0 {
showConfig(*configFile)
return
}
switch args[0] {
case "gen-html":
generateHTML(*configFile)
default:
fmt.Fprintf(os.Stderr, "Unknown command: %s\n", args[0])
os.Exit(1)
}
}
func loadConfig(yamlFile string) Config {
data, err := os.ReadFile(yamlFile)
if err != nil {
log.Fatalf("Failed to read YAML file: %v", err)
}
var config Config
err = yaml.Unmarshal(data, &config)
if err != nil {
log.Fatalf("Failed to parse YAML: %v", err)
}
return config
}
func showConfig(yamlFile string) {
config := loadConfig(yamlFile)
fmt.Printf("Config loaded successfully:\n")
fmt.Printf("Listen addresses: %v\n", config.Listen)
fmt.Printf("Checkpoints: %s\n", config.Checkpoints)
fmt.Printf("Number of logs: %d\n", len(config.Logs))
for i, logEntry := range config.Logs {
fmt.Printf("Log %d: %s (Period: %d, Pool size: %d)\n",
i+1, logEntry.ShortName, logEntry.Period, logEntry.PoolSize)
}
}
func generateHTML(yamlFile string) {
config := loadConfig(yamlFile)
// Check that all local directories exist
for _, logEntry := range config.Logs {
if _, err := os.Stat(logEntry.LocalDirectory); os.IsNotExist(err) {
log.Fatalf("User is required to create %s", logEntry.LocalDirectory)
}
}
// Compute key information for each log
for i := range config.Logs {
err := computeKeyInfo(&config.Logs[i])
if err != nil {
log.Fatalf("Failed to compute key info for %s: %v", config.Logs[i].ShortName, err)
}
}
tmpl, err := template.New("html").Parse(htmlTemplate)
if err != nil {
log.Fatalf("Failed to parse template: %v", err)
}
// Write HTML file to each log's local directory
for _, logEntry := range config.Logs {
indexPath := fmt.Sprintf("%s/index.html", logEntry.LocalDirectory)
file, err := os.Create(indexPath)
if err != nil {
log.Fatalf("Failed to create %s: %v", indexPath, err)
}
err = tmpl.Execute(file, config)
if err != nil {
file.Close()
log.Fatalf("Failed to write HTML to %s: %v", indexPath, err)
}
file.Close()
fmt.Printf("Generated %s\n", indexPath)
}
}
func computeKeyInfo(logEntry *Log) error {
// Read the private key file
keyData, err := os.ReadFile(logEntry.Secret)
if err != nil {
return fmt.Errorf("failed to read key file: %v", err)
}
// Parse PEM block
block, _ := pem.Decode(keyData)
if block == nil {
return fmt.Errorf("failed to decode PEM block")
}
// Parse EC private key
privKey, err := x509.ParseECPrivateKey(block.Bytes)
if err != nil {
return fmt.Errorf("failed to parse EC private key: %v", err)
}
// Extract public key
pubKey := &privKey.PublicKey
// Convert public key to DER format
pubKeyDER, err := x509.MarshalPKIXPublicKey(pubKey)
if err != nil {
return fmt.Errorf("failed to marshal public key: %v", err)
}
// Create PEM format
pubKeyPEM := pem.EncodeToMemory(&pem.Block{
Type: "PUBLIC KEY",
Bytes: pubKeyDER,
})
// Compute Log ID (SHA-256 of the DER-encoded public key)
logIDBytes := sha256.Sum256(pubKeyDER)
logID := base64.StdEncoding.EncodeToString(logIDBytes[:])
// Base64 encode DER for download link
pubKeyDERB64 := base64.StdEncoding.EncodeToString(pubKeyDER)
// Set computed fields
logEntry.LogID = logID
logEntry.PublicKeyPEM = string(pubKeyPEM)
logEntry.PublicKeyDERB64 = pubKeyDERB64
return nil
}