cri-o/vendor/github.com/containers/image/docker/docker_client.go
Antonio Murdaca e269cb8b7e
new vendoring
Signed-off-by: Antonio Murdaca <runcom@redhat.com>
2016-09-22 18:17:45 +02:00

373 lines
11 KiB
Go

package docker
import (
"crypto/tls"
"encoding/base64"
"encoding/json"
"fmt"
"io"
"io/ioutil"
"net/http"
"os"
"path/filepath"
"strings"
"time"
"github.com/Sirupsen/logrus"
"github.com/containers/image/types"
"github.com/docker/docker/pkg/homedir"
)
const (
dockerHostname = "docker.io"
dockerRegistry = "registry-1.docker.io"
dockerAuthRegistry = "https://index.docker.io/v1/"
dockerCfg = ".docker"
dockerCfgFileName = "config.json"
dockerCfgObsolete = ".dockercfg"
baseURL = "%s://%s/v2/"
tagsURL = "%s/tags/list"
manifestURL = "%s/manifests/%s"
blobsURL = "%s/blobs/%s"
blobUploadURL = "%s/blobs/uploads/"
)
// dockerClient is configuration for dealing with a single Docker registry.
type dockerClient struct {
ctx *types.SystemContext
registry string
username string
password string
wwwAuthenticate string // Cache of a value set by ping() if scheme is not empty
scheme string // Cache of a value returned by a successful ping() if not empty
client *http.Client
signatureBase signatureStorageBase
}
// newDockerClient returns a new dockerClient instance for refHostname (a host a specified in the Docker image reference, not canonicalized to dockerRegistry)
// “write” specifies whether the client will be used for "write" access (in particular passed to lookaside.go:toplevelFromSection)
func newDockerClient(ctx *types.SystemContext, ref dockerReference, write bool) (*dockerClient, error) {
registry := ref.ref.Hostname()
if registry == dockerHostname {
registry = dockerRegistry
}
username, password, err := getAuth(ref.ref.Hostname())
if err != nil {
return nil, err
}
var tr *http.Transport
if ctx != nil && (ctx.DockerCertPath != "" || ctx.DockerInsecureSkipTLSVerify) {
tlsc := &tls.Config{}
if ctx.DockerCertPath != "" {
cert, err := tls.LoadX509KeyPair(filepath.Join(ctx.DockerCertPath, "cert.pem"), filepath.Join(ctx.DockerCertPath, "key.pem"))
if err != nil {
return nil, fmt.Errorf("Error loading x509 key pair: %s", err)
}
tlsc.Certificates = append(tlsc.Certificates, cert)
}
tlsc.InsecureSkipVerify = ctx.DockerInsecureSkipTLSVerify
tr = &http.Transport{
TLSClientConfig: tlsc,
}
}
client := &http.Client{
Timeout: 1 * time.Minute,
}
if tr != nil {
client.Transport = tr
}
sigBase, err := configuredSignatureStorageBase(ctx, ref, write)
if err != nil {
return nil, err
}
return &dockerClient{
ctx: ctx,
registry: registry,
username: username,
password: password,
client: client,
signatureBase: sigBase,
}, nil
}
// makeRequest creates and executes a http.Request with the specified parameters, adding authentication and TLS options for the Docker client.
// url is NOT an absolute URL, but a path relative to the /v2/ top-level API path. The host name and schema is taken from the client or autodetected.
func (c *dockerClient) makeRequest(method, url string, headers map[string][]string, stream io.Reader) (*http.Response, error) {
if c.scheme == "" {
pr, err := c.ping()
if err != nil {
return nil, err
}
c.wwwAuthenticate = pr.WWWAuthenticate
c.scheme = pr.scheme
}
url = fmt.Sprintf(baseURL, c.scheme, c.registry) + url
return c.makeRequestToResolvedURL(method, url, headers, stream, -1)
}
// makeRequestToResolvedURL creates and executes a http.Request with the specified parameters, adding authentication and TLS options for the Docker client.
// streamLen, if not -1, specifies the length of the data expected on stream.
// makeRequest should generally be preferred.
func (c *dockerClient) makeRequestToResolvedURL(method, url string, headers map[string][]string, stream io.Reader, streamLen int64) (*http.Response, error) {
req, err := http.NewRequest(method, url, stream)
if err != nil {
return nil, err
}
if streamLen != -1 { // Do not blindly overwrite if streamLen == -1, http.NewRequest above can figure out the length of bytes.Reader and similar objects without us having to compute it.
req.ContentLength = streamLen
}
req.Header.Set("Docker-Distribution-API-Version", "registry/2.0")
for n, h := range headers {
for _, hh := range h {
req.Header.Add(n, hh)
}
}
if c.wwwAuthenticate != "" {
if err := c.setupRequestAuth(req); err != nil {
return nil, err
}
}
logrus.Debugf("%s %s", method, url)
res, err := c.client.Do(req)
if err != nil {
return nil, err
}
return res, nil
}
func (c *dockerClient) setupRequestAuth(req *http.Request) error {
tokens := strings.SplitN(strings.TrimSpace(c.wwwAuthenticate), " ", 2)
if len(tokens) != 2 {
return fmt.Errorf("expected 2 tokens in WWW-Authenticate: %d, %s", len(tokens), c.wwwAuthenticate)
}
switch tokens[0] {
case "Basic":
req.SetBasicAuth(c.username, c.password)
return nil
case "Bearer":
// FIXME? This gets a new token for every API request;
// we may be easily able to reuse a previous token, e.g.
// for OpenShift the token only identifies the user and does not vary
// across operations. Should we just try the request first, and
// only get a new token on failure?
// OTOH what to do with the single-use body stream in that case?
// Try performing the request, expecting it to fail.
testReq := *req
// Do not use the body stream, or we couldn't reuse it for the "real" call later.
testReq.Body = nil
testReq.ContentLength = 0
res, err := c.client.Do(&testReq)
if err != nil {
return err
}
chs := parseAuthHeader(res.Header)
if res.StatusCode != http.StatusUnauthorized || chs == nil || len(chs) == 0 {
// no need for bearer? wtf?
return nil
}
// Arbitrarily use the first challenge, there is no reason to expect more than one.
challenge := chs[0]
if challenge.Scheme != "bearer" { // Another artifact of trying to handle WWW-Authenticate before it actually happens.
return fmt.Errorf("Unimplemented: WWW-Authenticate Bearer replaced by %#v", challenge.Scheme)
}
realm, ok := challenge.Parameters["realm"]
if !ok {
return fmt.Errorf("missing realm in bearer auth challenge")
}
service, _ := challenge.Parameters["service"] // Will be "" if not present
scope, _ := challenge.Parameters["scope"] // Will be "" if not present
token, err := c.getBearerToken(realm, service, scope)
if err != nil {
return err
}
req.Header.Set("Authorization", fmt.Sprintf("Bearer %s", token))
return nil
}
return fmt.Errorf("no handler for %s authentication", tokens[0])
// support docker bearer with authconfig's Auth string? see docker2aci
}
func (c *dockerClient) getBearerToken(realm, service, scope string) (string, error) {
authReq, err := http.NewRequest("GET", realm, nil)
if err != nil {
return "", err
}
getParams := authReq.URL.Query()
if service != "" {
getParams.Add("service", service)
}
if scope != "" {
getParams.Add("scope", scope)
}
authReq.URL.RawQuery = getParams.Encode()
if c.username != "" && c.password != "" {
authReq.SetBasicAuth(c.username, c.password)
}
// insecure for now to contact the external token service
tr := &http.Transport{TLSClientConfig: &tls.Config{InsecureSkipVerify: true}}
client := &http.Client{Transport: tr}
res, err := client.Do(authReq)
if err != nil {
return "", err
}
defer res.Body.Close()
switch res.StatusCode {
case http.StatusUnauthorized:
return "", fmt.Errorf("unable to retrieve auth token: 401 unauthorized")
case http.StatusOK:
break
default:
return "", fmt.Errorf("unexpected http code: %d, URL: %s", res.StatusCode, authReq.URL)
}
tokenBlob, err := ioutil.ReadAll(res.Body)
if err != nil {
return "", err
}
tokenStruct := struct {
Token string `json:"token"`
}{}
if err := json.Unmarshal(tokenBlob, &tokenStruct); err != nil {
return "", err
}
// TODO(runcom): reuse tokens?
//hostAuthTokens, ok = rb.hostsV2AuthTokens[req.URL.Host]
//if !ok {
//hostAuthTokens = make(map[string]string)
//rb.hostsV2AuthTokens[req.URL.Host] = hostAuthTokens
//}
//hostAuthTokens[repo] = tokenStruct.Token
return tokenStruct.Token, nil
}
func getAuth(hostname string) (string, string, error) {
// TODO(runcom): get this from *cli.Context somehow
//if username != "" && password != "" {
//return username, password, nil
//}
if hostname == dockerHostname {
hostname = dockerAuthRegistry
}
dockerCfgPath := filepath.Join(getDefaultConfigDir(".docker"), dockerCfgFileName)
if _, err := os.Stat(dockerCfgPath); err == nil {
j, err := ioutil.ReadFile(dockerCfgPath)
if err != nil {
return "", "", err
}
var dockerAuth dockerConfigFile
if err := json.Unmarshal(j, &dockerAuth); err != nil {
return "", "", err
}
// try the normal case
if c, ok := dockerAuth.AuthConfigs[hostname]; ok {
return decodeDockerAuth(c.Auth)
}
} else if os.IsNotExist(err) {
oldDockerCfgPath := filepath.Join(getDefaultConfigDir(dockerCfgObsolete))
if _, err := os.Stat(oldDockerCfgPath); err != nil {
return "", "", nil //missing file is not an error
}
j, err := ioutil.ReadFile(oldDockerCfgPath)
if err != nil {
return "", "", err
}
var dockerAuthOld map[string]dockerAuthConfigObsolete
if err := json.Unmarshal(j, &dockerAuthOld); err != nil {
return "", "", err
}
if c, ok := dockerAuthOld[hostname]; ok {
return decodeDockerAuth(c.Auth)
}
} else {
// if file is there but we can't stat it for any reason other
// than it doesn't exist then stop
return "", "", fmt.Errorf("%s - %v", dockerCfgPath, err)
}
return "", "", nil
}
type apiErr struct {
Code string
Message string
Detail interface{}
}
type pingResponse struct {
WWWAuthenticate string
APIVersion string
scheme string
errors []apiErr
}
func (c *dockerClient) ping() (*pingResponse, error) {
ping := func(scheme string) (*pingResponse, error) {
url := fmt.Sprintf(baseURL, scheme, c.registry)
resp, err := c.client.Get(url)
logrus.Debugf("Ping %s err %#v", url, err)
if err != nil {
return nil, err
}
defer resp.Body.Close()
logrus.Debugf("Ping %s status %d", scheme+"://"+c.registry+"/v2/", resp.StatusCode)
if resp.StatusCode != http.StatusOK && resp.StatusCode != http.StatusUnauthorized {
return nil, fmt.Errorf("error pinging repository, response code %d", resp.StatusCode)
}
pr := &pingResponse{}
pr.WWWAuthenticate = resp.Header.Get("WWW-Authenticate")
pr.APIVersion = resp.Header.Get("Docker-Distribution-Api-Version")
pr.scheme = scheme
if resp.StatusCode == http.StatusUnauthorized {
type APIErrors struct {
Errors []apiErr
}
errs := &APIErrors{}
if err := json.NewDecoder(resp.Body).Decode(errs); err != nil {
return nil, err
}
pr.errors = errs.Errors
}
return pr, nil
}
pr, err := ping("https")
if err != nil && c.ctx.DockerInsecureSkipTLSVerify {
pr, err = ping("http")
}
return pr, err
}
func getDefaultConfigDir(confPath string) string {
return filepath.Join(homedir.Get(), confPath)
}
type dockerAuthConfigObsolete struct {
Auth string `json:"auth"`
}
type dockerAuthConfig struct {
Auth string `json:"auth,omitempty"`
}
type dockerConfigFile struct {
AuthConfigs map[string]dockerAuthConfig `json:"auths"`
}
func decodeDockerAuth(s string) (string, string, error) {
decoded, err := base64.StdEncoding.DecodeString(s)
if err != nil {
return "", "", err
}
parts := strings.SplitN(string(decoded), ":", 2)
if len(parts) != 2 {
// if it's invalid just skip, as docker does
return "", "", nil
}
user := parts[0]
password := strings.Trim(parts[1], "\x00")
return user, password, nil
}