blob: ae41c26a5a94c602782e13bd1c2d10fc15c8558d [file] [log] [blame]
// Copyright 2018 The Fuchsia Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
package botanist
import (
"context"
"crypto/rand"
"crypto/rsa"
"crypto/x509"
"encoding/pem"
"fmt"
"net"
"time"
"fuchsia.googlesource.com/tools/retry"
"golang.org/x/crypto/ssh"
)
const (
// Default SSH server port.
SSHPort = 22
// Default RSA key size.
RSAKeySize = 2048
)
// GenerateKeyPair generates a pair of private/public keys.
func GenerateKeyPair(bitSize int) ([]byte, []byte, error) {
key, err := rsa.GenerateKey(rand.Reader, bitSize)
if err != nil {
return nil, nil, err
}
pubkey, err := ssh.NewPublicKey(&key.PublicKey)
if err != nil {
return nil, nil, err
}
pembuf := pubkey.Marshal()
var privateKey = &pem.Block{
Type: "RSA PRIVATE KEY",
Bytes: x509.MarshalPKCS1PrivateKey(key),
}
buf := pem.EncodeToMemory(privateKey)
return pembuf, buf, nil
}
func ConnectSSH(ctx context.Context, address net.Addr, config *ssh.ClientConfig) (*ssh.Client, error) {
var client *ssh.Client
// TODO: figure out optimal backoff time and number of retries
err := retry.Retry(ctx, retry.WithMaxRetries(retry.NewConstantBackoff(time.Second), 10), func() error {
var err error
client, err = ssh.Dial(address.Network(), address.String(), config)
return err
}, nil)
if err != nil {
return nil, fmt.Errorf("cannot connect to address '%s': %v", address, err)
}
return client, nil
}