Feature: Integrate crypto/tls/generate_cert.go command

1 files changed, 158 insertions, 0 deletions

diff --git a/cmd/cert.go b/cmd/cert.go
new file mode 100644
index 0000000000..b693b7d94e
--- /dev/null
+++ b/cmd/cert.go
@@ -0,0 +1,158 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Copyright 2014 The Gogs Authors. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+package cmd
+
+import (
+	"crypto/ecdsa"
+	"crypto/elliptic"
+	"crypto/rand"
+	"crypto/rsa"
+	"crypto/x509"
+	"crypto/x509/pkix"
+	"encoding/pem"
+	"log"
+	"math/big"
+	"net"
+	"os"
+	"strings"
+	"time"
+
+	"github.com/codegangsta/cli"
+)
+
+var CmdCert = cli.Command{
+	Name:  "cert",
+	Usage: "Generate self-signed certificate",
+	Description: `Generate a self-signed X.509 certificate for a TLS server. 
+Outputs to 'cert.pem' and 'key.pem' and will overwrite existing files.`,
+	Action: runCert,
+	Flags: []cli.Flag{
+		cli.StringFlag{"host", "", "Comma-separated hostnames and IPs to generate a certificate for", ""},
+		cli.StringFlag{"ecdsa-curve", "", "ECDSA curve to use to generate a key. Valid values are P224, P256, P384, P521", ""},
+		cli.IntFlag{"rsa-bits", 2048, "Size of RSA key to generate. Ignored if --ecdsa-curve is set", ""},
+		cli.StringFlag{"start-date", "", "Creation date formatted as Jan 1 15:04:05 2011", ""},
+		cli.DurationFlag{"duration", 365 * 24 * time.Hour, "Duration that certificate is valid for", ""},
+		cli.BoolFlag{"ca", "whether this cert should be its own Certificate Authority", ""},
+	},
+}
+
+func publicKey(priv interface{}) interface{} {
+	switch k := priv.(type) {
+	case *rsa.PrivateKey:
+		return &k.PublicKey
+	case *ecdsa.PrivateKey:
+		return &k.PublicKey
+	default:
+		return nil
+	}
+}
+
+func pemBlockForKey(priv interface{}) *pem.Block {
+	switch k := priv.(type) {
+	case *rsa.PrivateKey:
+		return &pem.Block{Type: "RSA PRIVATE KEY", Bytes: x509.MarshalPKCS1PrivateKey(k)}
+	case *ecdsa.PrivateKey:
+		b, err := x509.MarshalECPrivateKey(k)
+		if err != nil {
+			log.Fatal("unable to marshal ECDSA private key: %v", err)
+		}
+		return &pem.Block{Type: "EC PRIVATE KEY", Bytes: b}
+	default:
+		return nil
+	}
+}
+
+func runCert(ctx *cli.Context) {
+	if len(ctx.String("host")) == 0 {
+		log.Fatal("Missing required --host parameter")
+	}
+
+	var priv interface{}
+	var err error
+	switch ctx.String("ecdsa-curve") {
+	case "":
+		priv, err = rsa.GenerateKey(rand.Reader, ctx.Int("rsa-bits"))
+	case "P224":
+		priv, err = ecdsa.GenerateKey(elliptic.P224(), rand.Reader)
+	case "P256":
+		priv, err = ecdsa.GenerateKey(elliptic.P256(), rand.Reader)
+	case "P384":
+		priv, err = ecdsa.GenerateKey(elliptic.P384(), rand.Reader)
+	case "P521":
+		priv, err = ecdsa.GenerateKey(elliptic.P521(), rand.Reader)
+	default:
+		log.Fatalf("Unrecognized elliptic curve: %q", ctx.String("ecdsa-curve"))
+	}
+	if err != nil {
+		log.Fatalf("Failed to generate private key: %s", err)
+	}
+
+	var notBefore time.Time
+	if len(ctx.String("start-date")) == 0 {
+		notBefore = time.Now()
+	} else {
+		notBefore, err = time.Parse("Jan 2 15:04:05 2006", ctx.String("start-date"))
+		if err != nil {
+			log.Fatalf("Failed to parse creation date: %s", err)
+		}
+	}
+
+	notAfter := notBefore.Add(ctx.Duration("duration"))
+
+	serialNumberLimit := new(big.Int).Lsh(big.NewInt(1), 128)
+	serialNumber, err := rand.Int(rand.Reader, serialNumberLimit)
+	if err != nil {
+		log.Fatalf("Failed to generate serial number: %s", err)
+	}
+
+	template := x509.Certificate{
+		SerialNumber: serialNumber,
+		Subject: pkix.Name{
+			Organization: []string{"Acme Co"},
+		},
+		NotBefore: notBefore,
+		NotAfter:  notAfter,
+
+		KeyUsage:              x509.KeyUsageKeyEncipherment | x509.KeyUsageDigitalSignature,
+		ExtKeyUsage:           []x509.ExtKeyUsage{x509.ExtKeyUsageServerAuth},
+		BasicConstraintsValid: true,
+	}
+
+	hosts := strings.Split(ctx.String("host"), ",")
+	for _, h := range hosts {
+		if ip := net.ParseIP(h); ip != nil {
+			template.IPAddresses = append(template.IPAddresses, ip)
+		} else {
+			template.DNSNames = append(template.DNSNames, h)
+		}
+	}
+
+	if ctx.Bool("ca") {
+		template.IsCA = true
+		template.KeyUsage |= x509.KeyUsageCertSign
+	}
+
+	derBytes, err := x509.CreateCertificate(rand.Reader, &template, &template, publicKey(priv), priv)
+	if err != nil {
+		log.Fatalf("Failed to create certificate: %s", err)
+	}
+
+	certOut, err := os.Create("cert.pem")
+	if err != nil {
+		log.Fatalf("Failed to open cert.pem for writing: %s", err)
+	}
+	pem.Encode(certOut, &pem.Block{Type: "CERTIFICATE", Bytes: derBytes})
+	certOut.Close()
+	log.Println("Written cert.pem")
+
+	keyOut, err := os.OpenFile("key.pem", os.O_WRONLY|os.O_CREATE|os.O_TRUNC, 0600)
+	if err != nil {
+		log.Fatal("failed to open key.pem for writing: %v", err)
+	}
+	pem.Encode(keyOut, pemBlockForKey(priv))
+	keyOut.Close()
+	log.Println("Written key.pem")
+}