1 files changed, 142 insertions, 0 deletions
diff --git a/pem2html.go b/pem2html.go
new file mode 100644
index 0000000..be0405d
--- /dev/null
+++ b/pem2html.go
@@ -0,0 +1,142 @@
+package main
+
+import (
+	"crypto/x509"
+	"encoding/pem"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"time"
+	"html/template"
+	"sort"
+)
+
+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...)
+	}
+}
+
+var tmpl = template.Must(template.New("pem2html").Parse(`<!DOCTYPE html>
+<html lang="en">
+<head>
+  <meta charset="utf-8">
+  <title>CT log</title>
+  <style>
+    html {
+      height: 100%;
+    }
+    body {
+      font-size: 10px;
+      font-family: monospace;
+      height: 100%;
+      display: flex;
+      align-items: center;
+    }
+    body > * {
+      margin: auto;
+    }
+    table {
+      border-collapse: collapse;
+    }
+    td, th {
+      padding: 0.1em 0.25em;
+      border: solid 1px black;
+      white-space: nowrap;
+    }
+    td {
+      background-color: #F3F3F3;
+    }
+    td a {
+      display: block;
+      width: 100%;
+      height: 100%;
+      color: black;
+    }
+  </style>
+</head>
+<body>
+<table>
+  <tr>
+    <th>Logged</th>
+    <th>NotBefore</th>
+    <th>NotAfter</th>
+    <th>Subject.CN</th>
+    <th>Issuer.O</th>
+  </tr>
+{{range $cert := .}}
+  <tr>
+    <td><a href="{{$cert.Url}}">{{$cert.Updated.Local.Format "2006-01-02 15:04:05"}}</a></td>
+    <td><a href="{{$cert.Url}}">{{$cert.X509.NotBefore.Local.Format "2006-01-02"}}</a></td>
+    <td><a href="{{$cert.Url}}">{{$cert.X509.NotAfter.Local.Format "2006-01-02"}}</a></td>
+    <td><a href="{{$cert.Url}}">{{$cert.X509.Subject.CommonName}}</a></td>
+    <td><a href="{{$cert.Url}}">{{$cert.X509.Issuer.Organization}}</a></td>
+  </tr>
+{{end}}
+</table>
+</body>
+</html>`))
+
+type Cert struct {
+	Url     string
+	Updated time.Time
+	X509    *x509.Certificate
+}
+
+type Certs []Cert
+
+ // Len is the number of elements in the collection.
+func (l Certs) Len() int {
+	return len(l)
+}
+
+// Less reports whether the element with
+// index i should sort before the element with index j.
+func (l Certs) Less(i, j int) bool {
+	return l[i].Updated.UTC().After(l[j].Updated.UTC())
+}
+
+// Swap swaps the elements with indexes i and j.
+func (l Certs) Swap(i, j int) {
+	tmp := l[i]
+	l[i] = l[j]
+	l[j] = tmp
+}
+
+func main() {
+	data, err := ioutil.ReadAll(os.Stdin)
+	handleErr(err, "Error reading stdin: %v\n")
+
+	var certs Certs
+	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")
+
+		str, ok := certPem.Headers["X-Crt-Sh-Updated"]
+		handleBool(ok, "Did not get X-Crt-Sh-Updated\n")
+		cert.Updated, err = time.Parse("2006-01-02T15:04:05Z", str)
+		handleErr(err, "Could not parse updated time")
+
+		cert.X509, err = x509.ParseCertificate(certPem.Bytes)
+		handleErr(err, "Error parsing cert: %v\n")
+
+		certs = append(certs, cert)
+	}
+
+	sort.Sort(certs)
+	tmpl.Execute(os.Stdout, certs)
+}