package registry // import "github.com/docker/docker/registry" import ( // this is required for some certificates _ "crypto/sha512" "encoding/json" "fmt" "net/http" "net/http/cookiejar" "net/url" "strings" "sync" "github.com/docker/docker/api/types/registry" "github.com/docker/docker/errdefs" "github.com/docker/docker/pkg/ioutils" "github.com/docker/docker/pkg/jsonmessage" "github.com/docker/docker/pkg/stringid" "github.com/pkg/errors" "github.com/sirupsen/logrus" ) // A session is used to communicate with a V1 registry type session struct { indexEndpoint *v1Endpoint client *http.Client id string } type authTransport struct { http.RoundTripper *registry.AuthConfig alwaysSetBasicAuth bool token []string mu sync.Mutex // guards modReq modReq map[*http.Request]*http.Request // original -> modified } // newAuthTransport handles the auth layer when communicating with a v1 registry (private or official) // // For private v1 registries, set alwaysSetBasicAuth to true. // // For the official v1 registry, if there isn't already an Authorization header in the request, // but there is an X-Docker-Token header set to true, then Basic Auth will be used to set the Authorization header. // After sending the request with the provided base http.RoundTripper, if an X-Docker-Token header, representing // a token, is present in the response, then it gets cached and sent in the Authorization header of all subsequent // requests. // // If the server sends a token without the client having requested it, it is ignored. // // This RoundTripper also has a CancelRequest method important for correct timeout handling. func newAuthTransport(base http.RoundTripper, authConfig *registry.AuthConfig, alwaysSetBasicAuth bool) *authTransport { if base == nil { base = http.DefaultTransport } return &authTransport{ RoundTripper: base, AuthConfig: authConfig, alwaysSetBasicAuth: alwaysSetBasicAuth, modReq: make(map[*http.Request]*http.Request), } } // cloneRequest returns a clone of the provided *http.Request. // The clone is a shallow copy of the struct and its Header map. func cloneRequest(r *http.Request) *http.Request { // shallow copy of the struct r2 := new(http.Request) *r2 = *r // deep copy of the Header r2.Header = make(http.Header, len(r.Header)) for k, s := range r.Header { r2.Header[k] = append([]string(nil), s...) } return r2 } // RoundTrip changes an HTTP request's headers to add the necessary // authentication-related headers func (tr *authTransport) RoundTrip(orig *http.Request) (*http.Response, error) { // Authorization should not be set on 302 redirect for untrusted locations. // This logic mirrors the behavior in addRequiredHeadersToRedirectedRequests. // As the authorization logic is currently implemented in RoundTrip, // a 302 redirect is detected by looking at the Referrer header as go http package adds said header. // This is safe as Docker doesn't set Referrer in other scenarios. if orig.Header.Get("Referer") != "" && !trustedLocation(orig) { return tr.RoundTripper.RoundTrip(orig) } req := cloneRequest(orig) tr.mu.Lock() tr.modReq[orig] = req tr.mu.Unlock() if tr.alwaysSetBasicAuth { if tr.AuthConfig == nil { return nil, errors.New("unexpected error: empty auth config") } req.SetBasicAuth(tr.Username, tr.Password) return tr.RoundTripper.RoundTrip(req) } // Don't override if req.Header.Get("Authorization") == "" { if req.Header.Get("X-Docker-Token") == "true" && tr.AuthConfig != nil && len(tr.Username) > 0 { req.SetBasicAuth(tr.Username, tr.Password) } else if len(tr.token) > 0 { req.Header.Set("Authorization", "Token "+strings.Join(tr.token, ",")) } } resp, err := tr.RoundTripper.RoundTrip(req) if err != nil { tr.mu.Lock() delete(tr.modReq, orig) tr.mu.Unlock() return nil, err } if len(resp.Header["X-Docker-Token"]) > 0 { tr.token = resp.Header["X-Docker-Token"] } resp.Body = &ioutils.OnEOFReader{ Rc: resp.Body, Fn: func() { tr.mu.Lock() delete(tr.modReq, orig) tr.mu.Unlock() }, } return resp, nil } // CancelRequest cancels an in-flight request by closing its connection. func (tr *authTransport) CancelRequest(req *http.Request) { type canceler interface { CancelRequest(*http.Request) } if cr, ok := tr.RoundTripper.(canceler); ok { tr.mu.Lock() modReq := tr.modReq[req] delete(tr.modReq, req) tr.mu.Unlock() cr.CancelRequest(modReq) } } func authorizeClient(client *http.Client, authConfig *registry.AuthConfig, endpoint *v1Endpoint) error { var alwaysSetBasicAuth bool // If we're working with a standalone private registry over HTTPS, send Basic Auth headers // alongside all our requests. if endpoint.String() != IndexServer && endpoint.URL.Scheme == "https" { info, err := endpoint.ping() if err != nil { return err } if info.Standalone && authConfig != nil { logrus.Debugf("Endpoint %s is eligible for private registry. Enabling decorator.", endpoint.String()) alwaysSetBasicAuth = true } } // Annotate the transport unconditionally so that v2 can // properly fallback on v1 when an image is not found. client.Transport = newAuthTransport(client.Transport, authConfig, alwaysSetBasicAuth) jar, err := cookiejar.New(nil) if err != nil { return errdefs.System(errors.New("cookiejar.New is not supposed to return an error")) } client.Jar = jar return nil } func newSession(client *http.Client, endpoint *v1Endpoint) *session { return &session{ client: client, indexEndpoint: endpoint, id: stringid.GenerateRandomID(), } } // defaultSearchLimit is the default value for maximum number of returned search results. const defaultSearchLimit = 25 // searchRepositories performs a search against the remote repository func (r *session) searchRepositories(term string, limit int) (*registry.SearchResults, error) { if limit == 0 { limit = defaultSearchLimit } if limit < 1 || limit > 100 { return nil, invalidParamf("limit %d is outside the range of [1, 100]", limit) } logrus.Debugf("Index server: %s", r.indexEndpoint) u := r.indexEndpoint.String() + "search?q=" + url.QueryEscape(term) + "&n=" + url.QueryEscape(fmt.Sprintf("%d", limit)) req, err := http.NewRequest(http.MethodGet, u, nil) if err != nil { return nil, invalidParamWrapf(err, "error building request") } // Have the AuthTransport send authentication, when logged in. req.Header.Set("X-Docker-Token", "true") res, err := r.client.Do(req) if err != nil { return nil, errdefs.System(err) } defer res.Body.Close() if res.StatusCode != http.StatusOK { return nil, &jsonmessage.JSONError{ Message: fmt.Sprintf("Unexpected status code %d", res.StatusCode), Code: res.StatusCode, } } result := new(registry.SearchResults) return result, errors.Wrap(json.NewDecoder(res.Body).Decode(result), "error decoding registry search results") }