github.com/sneal/packer@v0.5.2/builder/googlecompute/step_create_ssh_key.go (about)

     1  package googlecompute
     2  
     3  import (
     4  	"code.google.com/p/go.crypto/ssh"
     5  	"crypto/rand"
     6  	"crypto/rsa"
     7  	"crypto/x509"
     8  	"encoding/pem"
     9  	"fmt"
    10  	"github.com/mitchellh/multistep"
    11  	"github.com/mitchellh/packer/packer"
    12  	"os"
    13  )
    14  
    15  // StepCreateSSHKey represents a Packer build step that generates SSH key pairs.
    16  type StepCreateSSHKey struct {
    17  	Debug        bool
    18  	DebugKeyPath string
    19  }
    20  
    21  // Run executes the Packer build step that generates SSH key pairs.
    22  func (s *StepCreateSSHKey) Run(state multistep.StateBag) multistep.StepAction {
    23  	ui := state.Get("ui").(packer.Ui)
    24  
    25  	ui.Say("Creating temporary SSH key for instance...")
    26  	priv, err := rsa.GenerateKey(rand.Reader, 2048)
    27  	if err != nil {
    28  		err := fmt.Errorf("Error creating temporary ssh key: %s", err)
    29  		state.Put("error", err)
    30  		ui.Error(err.Error())
    31  		return multistep.ActionHalt
    32  	}
    33  
    34  	priv_blk := pem.Block{
    35  		Type:    "RSA PRIVATE KEY",
    36  		Headers: nil,
    37  		Bytes:   x509.MarshalPKCS1PrivateKey(priv),
    38  	}
    39  
    40  	pub, err := ssh.NewPublicKey(&priv.PublicKey)
    41  	if err != nil {
    42  		err := fmt.Errorf("Error creating temporary ssh key: %s", err)
    43  		state.Put("error", err)
    44  		ui.Error(err.Error())
    45  		return multistep.ActionHalt
    46  	}
    47  	state.Put("ssh_private_key", string(pem.EncodeToMemory(&priv_blk)))
    48  	state.Put("ssh_public_key", string(ssh.MarshalAuthorizedKey(pub)))
    49  
    50  	if s.Debug {
    51  		ui.Message(fmt.Sprintf("Saving key for debug purposes: %s", s.DebugKeyPath))
    52  		f, err := os.Create(s.DebugKeyPath)
    53  		if err != nil {
    54  			state.Put("error", fmt.Errorf("Error saving debug key: %s", err))
    55  			return multistep.ActionHalt
    56  		}
    57  
    58  		// Write out the key
    59  		err = pem.Encode(f, &priv_blk)
    60  		f.Close()
    61  		if err != nil {
    62  			state.Put("error", fmt.Errorf("Error saving debug key: %s", err))
    63  			return multistep.ActionHalt
    64  		}
    65  	}
    66  	return multistep.ActionContinue
    67  }
    68  
    69  // Nothing to clean up. SSH keys are associated with a single GCE instance.
    70  func (s *StepCreateSSHKey) Cleanup(state multistep.StateBag) {}