1 files changed, 144 insertions, 0 deletions
diff --git a/diff-pem2html.go b/diff-pem2html.go
new file mode 100644
index 0000000..8f3b1e9
--- /dev/null
+++ b/diff-pem2html.go
@@ -0,0 +1,144 @@
+package main
+
+import (
+	"crypto/x509"
+	"encoding/pem"
+	"fmt"
+	"html/template"
+	"io/ioutil"
+	"os"
+)
+
+func handleErr(err error, str string, a ...interface{}) {
+	a = append([]interface{}{err}, a...)
+	if err != nil {
+		fmt.Fprintf(os.Stderr, str, a...)
+		os.Exit(1)
+	}
+}
+
+func handleBool(ok bool, str string, a ...interface{}) {
+	if !ok {
+		fmt.Fprintf(os.Stderr, str, a...)
+		os.Exit(1)
+	}
+}
+
+var tmpl = template.Must(template.New("2html").Parse(`<!DOCTYPE html>
+<html lang="en">
+<head>
+  <meta charset="utf-8">
+  <title>CT log accuracy</title>
+  <style>
+    html {
+      height: 100%;
+    }
+    body {
+      font-size: 10px;
+      font-family: monospace;
+      height: 100%;
+      margin: 0;
+      display: flex;
+      align-items: center;
+    }
+    body > * {
+      margin: auto;
+    }
+    .diff-del, .diff-del a { color: red; }
+    .diff-add, .diff-add a { color: green; }
+    .diff-dat, .diff-dat a { color: blue; }
+    .diff-ctx, .diff-ctx a { color: black; }
+    tr:hover a {
+      background-color: #AAAAF3;
+    }
+    td a {
+      text-decoration: none;
+      padding: 0.1em 0.25em;
+      display: block;
+      width: 100%;
+      height: 100%;
+      color: black;
+    }
+  </style>
+  <script src="sorttable.js"></script>
+  <base target="_parent" />
+</head>
+<body>
+<table>
+  <tr class="diff-del"><td colspan=4>--- tls.pem</td></tr>
+  <tr class="diff-add"><td colspan=4>+++ crtsh.pem</td></tr>
+  <tr class="diff-dat"><td colspan=4>@@ -1,{{.nTLS}} +1,{{.nCrtSh}} @@</td></tr>
+{{range $cert := .certs}}
+  <tr class={{$cert.Class}}>
+    <td><a href="{{$cert.Url}}">{{if eq $cert.Pfix " "}}&nbsp;{{else}}{{$cert.Pfix}}{{end}}</a></td>
+    <td><a href="{{$cert.Url}}">{{$cert.X509.Subject.CommonName}}</a></td>
+    <td><a href="{{$cert.Url}}">{{$cert.X509.NotBefore.Local.Format "2006-01-02 15:04:05"}}</a></td>
+    <td><a href="{{$cert.Url}}">{{$cert.X509.NotAfter.Local.Format "2006-01-02 15:04:05"}}</a></td>
+  </tr>
+{{end}}
+</table>
+</body>
+</html>
+`))
+
+type Cert struct {
+	Url    string
+	action string
+	X509   *x509.Certificate
+}
+
+func (cert Cert) Pfix() string {
+	return map[string]string {
+		"add": "+",
+		"del": "-",
+		"ctx": " ",
+	}[cert.action]
+}
+
+func (cert Cert) Class() string {
+	return "diff-" + cert.action
+}
+
+func main() {
+	data, err := ioutil.ReadAll(os.Stdin)
+	handleErr(err, "Error reading stdin: %v\n")
+
+	var certs []Cert
+	a := 0
+	b := 0
+	for len(data) > 0 {
+		var certPem *pem.Block
+		certPem, data = pem.Decode(data)
+
+		var ok bool
+		var cert Cert
+
+		cert.Url, ok = certPem.Headers["X-Crt-Sh-Url"]
+		handleBool(ok, "Did not get X-Crt-Sh-Url\n")
+
+		cert.action, ok = certPem.Headers["X-Diff-Action"]
+		handleBool(ok, "Did not get X-Diff-Action\n")
+		switch cert.action {
+		case "add":
+			b++
+		case "del":
+			a++
+		case "ctx":
+			a++
+			b++
+		default:
+			handleBool(false, "Unknown X-Diff-Action: %q\n", cert.action)
+		}
+
+		cert.X509, err = x509.ParseCertificate(certPem.Bytes)
+		handleErr(err, "Error parsing cert: %v\n")
+
+		certs = append(certs, cert)
+	}
+
+	handleErr(tmpl.Execute(os.Stdout, map[string]interface{}{
+		"certs":certs,
+		"nTLS": a,
+		"nCrtSh": b,
+	}), "Could not execute template: %v\n")
+}