Files
cheese/tesseract/genconf/roots.go
2025-08-24 11:44:28 +02:00

99 lines
2.2 KiB
Go

package main
import (
"encoding/base64"
"encoding/json"
"encoding/pem"
"fmt"
"log"
"net/http"
"os"
"strings"
)
type CTLogRootsResponse struct {
Certificates []string `json:"certificates"`
}
func generateRoots(args []string) {
sourceURL := "https://rennet2027h2.log.ct.ipng.ch/"
outputFile := "roots.pem"
// Parse command line arguments
for i := 0; i < len(args); i++ {
switch args[i] {
case "--source":
if i+1 >= len(args) {
log.Fatal("--source flag requires a URL argument")
}
sourceURL = args[i+1]
i++ // Skip the next argument since we used it
case "--output":
if i+1 >= len(args) {
log.Fatal("--output flag requires a filename argument")
}
outputFile = args[i+1]
i++ // Skip the next argument since we used it
default:
log.Fatalf("Unknown argument: %s", args[i])
}
}
// Ensure source URL ends with /
if !strings.HasSuffix(sourceURL, "/") {
sourceURL += "/"
}
// Construct the get-roots URL
getRootsURL := sourceURL + "ct/v1/get-roots"
// Fetch roots from CT log
fmt.Printf("Fetching roots from: %s\n", getRootsURL)
resp, err := http.Get(getRootsURL)
if err != nil {
log.Fatalf("Failed to fetch roots: %v", err)
}
defer resp.Body.Close()
if resp.StatusCode != http.StatusOK {
log.Fatalf("HTTP request failed with status: %d", resp.StatusCode)
}
// Parse JSON response
var rootsResp CTLogRootsResponse
err = json.NewDecoder(resp.Body).Decode(&rootsResp)
if err != nil {
log.Fatalf("Failed to parse JSON response: %v", err)
}
// Create output file
outFile, err := os.Create(outputFile)
if err != nil {
log.Fatalf("Failed to create output file %s: %v", outputFile, err)
}
defer outFile.Close()
// Write each certificate as PEM
for _, certBase64 := range rootsResp.Certificates {
// Decode base64 certificate
certBytes, err := base64.StdEncoding.DecodeString(certBase64)
if err != nil {
log.Fatalf("Failed to decode certificate: %v", err)
}
// Create PEM block
pemBlock := &pem.Block{
Type: "CERTIFICATE",
Bytes: certBytes,
}
// Write PEM to file
err = pem.Encode(outFile, pemBlock)
if err != nil {
log.Fatalf("Failed to write PEM certificate: %v", err)
}
}
fmt.Printf("Successfully wrote %d certificates to %s\n", len(rootsResp.Certificates), outputFile)
}