github.com/StackPointCloud/packer@v0.10.2-0.20180716202532-b28098e0f79b/builder/azure/common/lin/step_create_cert.go (about)

     1  package lin
     2  
     3  import (
     4  	"context"
     5  	"crypto/rand"
     6  	"crypto/rsa"
     7  	"crypto/sha1"
     8  	"crypto/x509"
     9  	"crypto/x509/pkix"
    10  	"encoding/pem"
    11  	"fmt"
    12  	"log"
    13  	"math/big"
    14  	"time"
    15  
    16  	"github.com/hashicorp/packer/builder/azure/common/constants"
    17  
    18  	"github.com/hashicorp/packer/helper/multistep"
    19  	"github.com/hashicorp/packer/packer"
    20  )
    21  
    22  type StepCreateCert struct {
    23  	TmpServiceName string
    24  }
    25  
    26  func (s *StepCreateCert) Run(_ context.Context, state multistep.StateBag) multistep.StepAction {
    27  	ui := state.Get("ui").(packer.Ui)
    28  
    29  	ui.Say("Creating temporary certificate...")
    30  
    31  	err := s.createCert(state)
    32  	if err != nil {
    33  		err = fmt.Errorf("Error creating temporary certificate: %s", err)
    34  		state.Put("error", err)
    35  		ui.Error(err.Error())
    36  		return multistep.ActionHalt
    37  	}
    38  
    39  	return multistep.ActionContinue
    40  }
    41  
    42  func (s *StepCreateCert) Cleanup(state multistep.StateBag) {}
    43  
    44  func (s *StepCreateCert) createCert(state multistep.StateBag) error {
    45  
    46  	log.Println("createCert: Generating RSA key pair...")
    47  
    48  	priv, err := rsa.GenerateKey(rand.Reader, 2048)
    49  	if err != nil {
    50  		err = fmt.Errorf("Failed to Generate Private Key: %s", err)
    51  		return err
    52  	}
    53  
    54  	// ASN.1 DER encoded form
    55  	privkey := string(pem.EncodeToMemory(&pem.Block{
    56  		Type:  "RSA PRIVATE KEY",
    57  		Bytes: x509.MarshalPKCS1PrivateKey(priv),
    58  	}))
    59  
    60  	// Set the private key in the state bag for later
    61  	state.Put(constants.PrivateKey, privkey)
    62  	log.Printf("createCert: Private key:\n%s", privkey)
    63  
    64  	log.Println("createCert: Creating certificate...")
    65  
    66  	host := fmt.Sprintf("%s.cloudapp.net", s.TmpServiceName)
    67  	notBefore := time.Now()
    68  	notAfter := notBefore.Add(365 * 24 * time.Hour)
    69  
    70  	serialNumber, err := rand.Int(rand.Reader, new(big.Int).Lsh(big.NewInt(1), 128))
    71  	if err != nil {
    72  		err = fmt.Errorf("Failed to Generate Serial Number: %v", err)
    73  		return err
    74  	}
    75  
    76  	template := x509.Certificate{
    77  		SerialNumber: serialNumber,
    78  		Issuer: pkix.Name{
    79  			CommonName: host,
    80  		},
    81  		Subject: pkix.Name{
    82  			CommonName: host,
    83  		},
    84  		NotBefore: notBefore,
    85  		NotAfter:  notAfter,
    86  
    87  		KeyUsage:              x509.KeyUsageKeyEncipherment | x509.KeyUsageDigitalSignature,
    88  		ExtKeyUsage:           []x509.ExtKeyUsage{x509.ExtKeyUsageServerAuth},
    89  		BasicConstraintsValid: true,
    90  	}
    91  
    92  	derBytes, err := x509.CreateCertificate(rand.Reader, &template, &template, &priv.PublicKey, priv)
    93  	if err != nil {
    94  		err = fmt.Errorf("Failed to Create Certificate: %s", err)
    95  		return err
    96  	}
    97  
    98  	cert := string(pem.EncodeToMemory(&pem.Block{
    99  		Type:  "RSA PRIVATE KEY",
   100  		Bytes: derBytes,
   101  	}))
   102  	state.Put(constants.Certificate, cert)
   103  	log.Printf("createCert: Certificate:\n%s", cert)
   104  
   105  	h := sha1.New()
   106  	h.Write(derBytes)
   107  	thumbprint := fmt.Sprintf("%X", h.Sum(nil))
   108  	state.Put(constants.Thumbprint, thumbprint)
   109  	log.Printf("createCert: Thumbprint:\n%s", thumbprint)
   110  
   111  	return nil
   112  }