code review 1684051: crypto/tls, http: Make HTTPS servers easier.

src/pkg/crypto/tls/examples/generate_cert.go

+// Generate a self-signed X.509 certificate for a TLS server.

[adg, 2010/07/01 22:08:23]

Should mention that cert.pem and key.pem will be [over-]written.

[agl1, 2010/07/01 22:11:42]

Done.

+
+package main
+
+import (
+        "crypto/rsa"
+        "crypto/x509"
+        "encoding/pem"
+        "fmt"
+        "log"
+        "os"
+        "time"
+)
+
+func main() {
+        if len(os.Args) != 2 {
+                fmt.Printf("Usage: %s <hostname of server>\n", os.Args[0])
+                return
+        }
+
+        hostName := os.Args[1]
+
+        urandom, err := os.Open("/dev/urandom", os.O_RDONLY, 0)
+        if err != nil {
+                log.Crashf("failed to open /dev/urandom: %s\n", err)
+                return
+        }
+
+        log.Stdoutf("Generating RSA key\n")
+        priv, err := rsa.GenerateKey(urandom, 1024)
+        if err != nil {
+                log.Crashf("failed to generate private key: %s\n", err)
+                return
+        }
+
+        now := time.Seconds()
+
+        template := x509.Certificate{
+                SerialNumber: []byte{0},
+                Subject: x509.Name{
+                        CommonName:   hostName,
+                        Organization: "Acme Co",
+                },
+                NotBefore: time.SecondsToUTC(now - 300),
+                NotAfter:  time.SecondsToUTC(now + 86400*365), // valid for 1 year.
+
+                SubjectKeyId: []byte{1, 2, 3, 4},
+                KeyUsage:     x509.KeyUsageKeyEncipherment | x509.KeyUsageDigitalSignature,
+        }
+
+        derBytes, err := x509.CreateCertificate(urandom, &template, &template, &priv.PublicKey, priv)
+        if err != nil {
+                log.Crashf("Failed to create certificate: %s", err)
+                return
+        }
+
+        certOut, err := os.Open("cert.pem", os.O_WRONLY|os.O_CREAT, 0644)
+        if err != nil {
+                log.Crashf("failed to open cert.pem for writing: %s\n", err)
+                return
+        }
+        pem.Encode(certOut, &pem.Block{Type: "CERTIFICATE", Bytes: derBytes})
+        certOut.Close()
+        log.Stdoutf("written cert.pem\n")
+
+        keyOut, err := os.Open("key.pem", os.O_WRONLY|os.O_CREAT, 0600)
+        if err != nil {
+                log.Crashf("failed to open key.pem for writing: %s\n", err)
+                return
+        }
+        pem.Encode(keyOut, &pem.Block{Type: "RSA PRIVATE KEY", Bytes: x509.MarshalPKCS1PrivateKey(priv)})
+        keyOut.Close()
+        log.Stdoutf("written key.pem\n")
+}