packer-cn/builder/amazon/common/ssh.go

141 lines
3.8 KiB
Go

package common
import (
"errors"
"fmt"
"net"
"os"
"time"
"github.com/aws/aws-sdk-go/service/ec2"
packerssh "github.com/hashicorp/packer/communicator/ssh"
"github.com/mitchellh/multistep"
"golang.org/x/crypto/ssh"
"golang.org/x/crypto/ssh/agent"
)
type ec2Describer interface {
DescribeInstances(*ec2.DescribeInstancesInput) (*ec2.DescribeInstancesOutput, error)
}
var (
// modified in tests
sshHostSleepDuration = time.Second
)
// SSHHost returns a function that can be given to the SSH communicator
// for determining the SSH address based on the instance DNS name.
func SSHHost(e ec2Describer, sshInterface string) func(multistep.StateBag) (string, error) {
return func(state multistep.StateBag) (string, error) {
const tries = 2
// <= with current structure to check result of describing `tries` times
for j := 0; j <= tries; j++ {
var host string
i := state.Get("instance").(*ec2.Instance)
if sshInterface != "" {
switch sshInterface {
case "public_ip":
if i.PublicIpAddress != nil {
host = *i.PublicIpAddress
}
case "private_ip":
if i.PrivateIpAddress != nil {
host = *i.PrivateIpAddress
}
case "public_dns":
if i.PublicDnsName != nil {
host = *i.PublicDnsName
}
case "private_dns":
if i.PrivateDnsName != nil {
host = *i.PrivateDnsName
}
default:
panic(fmt.Sprintf("Unknown interface type: %s", sshInterface))
}
} else if i.VpcId != nil && *i.VpcId != "" {
if i.PublicIpAddress != nil && *i.PublicIpAddress != "" {
host = *i.PublicIpAddress
} else if i.PrivateIpAddress != nil && *i.PrivateIpAddress != "" {
host = *i.PrivateIpAddress
}
} else if i.PublicDnsName != nil && *i.PublicDnsName != "" {
host = *i.PublicDnsName
}
if host != "" {
return host, nil
}
r, err := e.DescribeInstances(&ec2.DescribeInstancesInput{
InstanceIds: []*string{i.InstanceId},
})
if err != nil {
return "", err
}
if len(r.Reservations) == 0 || len(r.Reservations[0].Instances) == 0 {
return "", fmt.Errorf("instance not found: %s", *i.InstanceId)
}
state.Put("instance", r.Reservations[0].Instances[0])
time.Sleep(sshHostSleepDuration)
}
return "", errors.New("couldn't determine address for instance")
}
}
// SSHConfig returns a function that can be used for the SSH communicator
// config for connecting to the instance created over SSH using the private key
// or password.
func SSHConfig(useAgent bool, username, password string) func(multistep.StateBag) (*ssh.ClientConfig, error) {
return func(state multistep.StateBag) (*ssh.ClientConfig, error) {
if useAgent {
authSock := os.Getenv("SSH_AUTH_SOCK")
if authSock == "" {
return nil, fmt.Errorf("SSH_AUTH_SOCK is not set")
}
sshAgent, err := net.Dial("unix", authSock)
if err != nil {
return nil, fmt.Errorf("Cannot connect to SSH Agent socket %q: %s", authSock, err)
}
return &ssh.ClientConfig{
User: username,
Auth: []ssh.AuthMethod{
ssh.PublicKeysCallback(agent.NewClient(sshAgent).Signers),
},
HostKeyCallback: ssh.InsecureIgnoreHostKey(),
}, nil
}
privateKey, hasKey := state.GetOk("privateKey")
if hasKey {
signer, err := ssh.ParsePrivateKey([]byte(privateKey.(string)))
if err != nil {
return nil, fmt.Errorf("Error setting up SSH config: %s", err)
}
return &ssh.ClientConfig{
User: username,
Auth: []ssh.AuthMethod{
ssh.PublicKeys(signer),
},
HostKeyCallback: ssh.InsecureIgnoreHostKey(),
}, nil
} else {
return &ssh.ClientConfig{
User: username,
HostKeyCallback: ssh.InsecureIgnoreHostKey(),
Auth: []ssh.AuthMethod{
ssh.Password(password),
ssh.KeyboardInteractive(
packerssh.PasswordKeyboardInteractive(password)),
}}, nil
}
}
}