Files
kubelogin/cli/cli.go
2018-08-24 14:02:42 +09:00

116 lines
3.8 KiB
Go

package cli
import (
"context"
"crypto/tls"
"crypto/x509"
"encoding/base64"
"fmt"
"io/ioutil"
"log"
"net/http"
"github.com/int128/kubelogin/auth"
"github.com/int128/kubelogin/kubeconfig"
flags "github.com/jessevdk/go-flags"
homedir "github.com/mitchellh/go-homedir"
"golang.org/x/oauth2"
)
// Parse parses command line arguments and returns a CLI instance.
func Parse(args []string) (*CLI, error) {
var cli CLI
parser := flags.NewParser(&cli, flags.HelpFlag)
args, err := parser.Parse()
if err != nil {
return nil, err
}
if len(args) > 0 {
return nil, fmt.Errorf("Too many argument")
}
return &cli, nil
}
// CLI represents an interface of this command.
type CLI struct {
KubeConfig string `long:"kubeconfig" default:"~/.kube/config" env:"KUBECONFIG" description:"Path to the kubeconfig file"`
SkipTLSVerify bool `long:"insecure-skip-tls-verify" env:"KUBELOGIN_INSECURE_SKIP_TLS_VERIFY" description:"If set, the server's certificate will not be checked for validity. This will make your HTTPS connections insecure"`
// CertificateAuthority string `long:"certificate-authority" env:"KUBELOGIN_CERTIFICATE_AUTHORITY" description:"Path to a cert file for the certificate authority"`
}
// ExpandKubeConfig returns an expanded KubeConfig path.
func (c *CLI) ExpandKubeConfig() (string, error) {
d, err := homedir.Expand(c.KubeConfig)
if err != nil {
return "", fmt.Errorf("Could not expand %s", c.KubeConfig)
}
return d, nil
}
// Run performs this command.
func (c *CLI) Run(ctx context.Context) error {
path, err := c.ExpandKubeConfig()
if err != nil {
return err
}
log.Printf("Reading %s", path)
cfg, err := kubeconfig.Load(path)
if err != nil {
return fmt.Errorf("Could not load kubeconfig: %s", err)
}
log.Printf("Using current context: %s", cfg.CurrentContext)
authInfo := kubeconfig.FindCurrentAuthInfo(cfg)
if authInfo == nil {
return fmt.Errorf("Could not find current context: %s", cfg.CurrentContext)
}
authProvider, err := kubeconfig.ToOIDCAuthProviderConfig(authInfo)
if err != nil {
return fmt.Errorf("Could not find auth-provider: %s", err)
}
tlsConfig, err := c.tlsConfig(authProvider)
if err != nil {
return fmt.Errorf("Could not configure TLS: %s", err)
}
client := &http.Client{Transport: &http.Transport{TLSClientConfig: tlsConfig}}
ctx = context.WithValue(ctx, oauth2.HTTPClient, client)
token, err := auth.GetTokenSet(ctx, authProvider.IDPIssuerURL(), authProvider.ClientID(), authProvider.ClientSecret())
if err != nil {
return fmt.Errorf("Authentication error: %s", err)
}
authProvider.SetIDToken(token.IDToken)
authProvider.SetRefreshToken(token.RefreshToken)
kubeconfig.Write(cfg, path)
log.Printf("Updated %s", path)
return nil
}
func (c *CLI) tlsConfig(authProvider *kubeconfig.OIDCAuthProviderConfig) (*tls.Config, error) {
p := x509.NewCertPool()
if authProvider.IDPCertificateAuthority() != "" {
b, err := ioutil.ReadFile(authProvider.IDPCertificateAuthority())
if err != nil {
return nil, fmt.Errorf("Could not read idp-certificate-authority: %s", err)
}
if p.AppendCertsFromPEM(b) != true {
return nil, fmt.Errorf("Could not load CA certificate from idp-certificate-authority: %s", err)
}
log.Printf("Using CA certificate: %s", authProvider.IDPCertificateAuthority())
}
if authProvider.IDPCertificateAuthorityData() != "" {
b, err := base64.StdEncoding.DecodeString(authProvider.IDPCertificateAuthorityData())
if err != nil {
return nil, fmt.Errorf("Could not decode idp-certificate-authority-data: %s", err)
}
if p.AppendCertsFromPEM(b) != true {
return nil, fmt.Errorf("Could not load CA certificate from idp-certificate-authority-data: %s", err)
}
log.Printf("Using CA certificate of idp-certificate-authority-data")
}
cfg := &tls.Config{InsecureSkipVerify: c.SkipTLSVerify}
if len(p.Subjects()) > 0 {
cfg.RootCAs = p
}
return cfg, nil
}