Merge pull request #1160 from euank/simpler-pass

config/credentials: don't run 'pass' to detect it
This commit is contained in:
Vincent Demeester 2018-07-02 09:40:47 +02:00 committed by GitHub
commit 9e36ff4491
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2 changed files with 2 additions and 210 deletions

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@ -1,12 +1,11 @@
package credentials package credentials
import ( import (
"github.com/docker/docker-credential-helpers/pass" "os/exec"
) )
func defaultCredentialsStore() string { func defaultCredentialsStore() string {
passStore := pass.Pass{} if _, err := exec.LookPath("pass"); err == nil {
if passStore.CheckInitialized() {
return "pass" return "pass"
} }

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@ -1,207 +0,0 @@
// A `pass` based credential helper. Passwords are stored as arguments to pass
// of the form: "$PASS_FOLDER/base64-url(serverURL)/username". We base64-url
// encode the serverURL, because under the hood pass uses files and folders, so
// /s will get translated into additional folders.
package pass
import (
"bytes"
"encoding/base64"
"errors"
"fmt"
"io/ioutil"
"os"
"os/exec"
"path"
"strings"
"sync"
"github.com/docker/docker-credential-helpers/credentials"
)
const PASS_FOLDER = "docker-credential-helpers"
// Pass handles secrets using Linux secret-service as a store.
type Pass struct{}
// Ideally these would be stored as members of Pass, but since all of Pass's
// methods have value receivers, not pointer receivers, and changing that is
// backwards incompatible, we assume that all Pass instances share the same configuration
// initializationMutex is held while initializing so that only one 'pass'
// round-tripping is done to check pass is functioning.
var initializationMutex sync.Mutex
var passInitialized bool
// CheckInitialized checks whether the password helper can be used. It
// internally caches and so may be safely called multiple times with no impact
// on performance, though the first call may take longer.
func (p Pass) CheckInitialized() bool {
return p.checkInitialized() == nil
}
func (p Pass) checkInitialized() error {
initializationMutex.Lock()
defer initializationMutex.Unlock()
if passInitialized {
return nil
}
// In principle, we could just run `pass init`. However, pass has a bug
// where if gpg fails, it doesn't always exit 1. Additionally, pass
// uses gpg2, but gpg is the default, which may be confusing. So let's
// just explictily check that pass actually can store and retreive a
// password.
password := "pass is initialized"
name := path.Join(getPassDir(), "docker-pass-initialized-check")
_, err := p.runPassHelper(password, "insert", "-f", "-m", name)
if err != nil {
return fmt.Errorf("error initializing pass: %v", err)
}
stored, err := p.runPassHelper("", "show", name)
if err != nil {
return fmt.Errorf("error fetching password during initialization: %v", err)
}
if stored != password {
return fmt.Errorf("error round-tripping password during initialization: %q != %q", password, stored)
}
passInitialized = true
return nil
}
func (p Pass) runPass(stdinContent string, args ...string) (string, error) {
if err := p.checkInitialized(); err != nil {
return "", err
}
return p.runPassHelper(stdinContent, args...)
}
func (p Pass) runPassHelper(stdinContent string, args ...string) (string, error) {
var stdout, stderr bytes.Buffer
cmd := exec.Command("pass", args...)
cmd.Stdin = strings.NewReader(stdinContent)
cmd.Stdout = &stdout
cmd.Stderr = &stderr
err := cmd.Run()
if err != nil {
return "", fmt.Errorf("%s: %s", err, stderr.String())
}
// trim newlines; pass v1.7.1+ includes a newline at the end of `show` output
return strings.TrimRight(stdout.String(), "\n\r"), nil
}
// Add adds new credentials to the keychain.
func (h Pass) Add(creds *credentials.Credentials) error {
if creds == nil {
return errors.New("missing credentials")
}
encoded := base64.URLEncoding.EncodeToString([]byte(creds.ServerURL))
_, err := h.runPass(creds.Secret, "insert", "-f", "-m", path.Join(PASS_FOLDER, encoded, creds.Username))
return err
}
// Delete removes credentials from the store.
func (h Pass) Delete(serverURL string) error {
if serverURL == "" {
return errors.New("missing server url")
}
encoded := base64.URLEncoding.EncodeToString([]byte(serverURL))
_, err := h.runPass("", "rm", "-rf", path.Join(PASS_FOLDER, encoded))
return err
}
func getPassDir() string {
passDir := "$HOME/.password-store"
if envDir := os.Getenv("PASSWORD_STORE_DIR"); envDir != "" {
passDir = envDir
}
return os.ExpandEnv(passDir)
}
// listPassDir lists all the contents of a directory in the password store.
// Pass uses fancy unicode to emit stuff to stdout, so rather than try
// and parse this, let's just look at the directory structure instead.
func listPassDir(args ...string) ([]os.FileInfo, error) {
passDir := getPassDir()
p := path.Join(append([]string{passDir, PASS_FOLDER}, args...)...)
contents, err := ioutil.ReadDir(p)
if err != nil {
if os.IsNotExist(err) {
return []os.FileInfo{}, nil
}
return nil, err
}
return contents, nil
}
// Get returns the username and secret to use for a given registry server URL.
func (h Pass) Get(serverURL string) (string, string, error) {
if serverURL == "" {
return "", "", errors.New("missing server url")
}
encoded := base64.URLEncoding.EncodeToString([]byte(serverURL))
if _, err := os.Stat(path.Join(getPassDir(), PASS_FOLDER, encoded)); err != nil {
if os.IsNotExist(err) {
return "", "", nil
}
return "", "", err
}
usernames, err := listPassDir(encoded)
if err != nil {
return "", "", err
}
if len(usernames) < 1 {
return "", "", fmt.Errorf("no usernames for %s", serverURL)
}
actual := strings.TrimSuffix(usernames[0].Name(), ".gpg")
secret, err := h.runPass("", "show", path.Join(PASS_FOLDER, encoded, actual))
return actual, secret, err
}
// List returns the stored URLs and corresponding usernames for a given credentials label
func (h Pass) List() (map[string]string, error) {
servers, err := listPassDir()
if err != nil {
return nil, err
}
resp := map[string]string{}
for _, server := range servers {
if !server.IsDir() {
continue
}
serverURL, err := base64.URLEncoding.DecodeString(server.Name())
if err != nil {
return nil, err
}
usernames, err := listPassDir(server.Name())
if err != nil {
return nil, err
}
if len(usernames) < 1 {
return nil, fmt.Errorf("no usernames for %s", serverURL)
}
resp[string(serverURL)] = strings.TrimSuffix(usernames[0].Name(), ".gpg")
}
return resp, nil
}